CYP1A2 genetic polymorphisms and adenocarcinoma lung cancer risk in the Tunisian population

AimsIn this study, the effects of four single nucleotide polymorphisms (SNPs), ? 3860G > A, ? 2467delT, ? 739T > G and ? 163C > A, of CYP1A2 gene on lung cancer were evaluated in Tunisian population.Main methodsFour polymorphisms of CYP1A2 gene were analysed in 109 healthy smokers and in 101 lung cancer cases, including 63 with squamous cell carcinoma (SCC) and 41 with adenocarcinoma (AD). The genotyping for the SNPs ? 3860 G > A, ? 2467delT, ? 739T > G and ? 163C > A was performed by polymerase chain reaction (PCR)-restriction fragment length polymorphism analysis.Key findingsThe results showed that smokers with CYP1A2 gene polymorphisms were associated with an increased risk for the development of lung AD. There was however no significant increased risk of developing lung SCC in smokers having CYP1A2 gene polymorphisms. An increased risk of developing AD was observed in smokers who are carriers of at least one copy of ? 3680A or ? 739G giving a significant odds ratio (OR) of 6.02 (CI = 2.91–12.9) and 3.01 (CI = 1.54–5.98), respectively.SignificanceThese genotyping data are consistent with the hypothesis that tobacco-specific-N-nitrosamines (TSN) such as 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) are major contributors to the development of lung AD and that CYP1A2 gene product plays an important role in the metabolic activation of NNK. This study suggests that SNPs of CYP1A2 could be considered as promising biomarkers in the aetiology of lung AD in smokers.     

Genomic damages in peripheral blood lymphocytes and association with polymorphisms of three glutathione S-transferases in workers exposed to formaldehyde

DNA and chromosome damages in peripheral blood lymphocytes were evaluated in 151 workers occupationally exposed to formaldehyde (FA) and 112 non-FA exposed controls. The effects of polymorphisms in three glutathione-S-transferase (GSTs) genes on the DNA and chromosome damages were assessed as well. Alkaline comet assay and cytokinesis-block micronucleus (CBMN) assay were used to determine DNA and chromosome damages, respectively. The genotypes of GSTP1 (Ile105Val), GSTT1, and GSTM1 were assayed. The mean 8-h time-weighted average (TWA) concentrations of FA in two plywood factories were 0.83 ppm (range: 0.08–6.30 ppm). FA-exposed workers had higher olive tail moment (TM) and CBMN frequency compared with controls (Olive TM, 3.54, 95%CI = 3.19–3.93 vs. 0.93, 95%CI = 0.78–1.10, P < 0.01; CBMN frequency, 5.51 ± 3.37 vs. 2.67 ± 1.32, P < 0.01). Olive TM and the CBMN frequency also had a dose-dependent relation with the personal FA exposure. Significant association between FA exposure history and olive TM and CBMN frequency were also identified. The level of olive TM was slightly higher in FA-exposed workers with GSTM1 null genotype than those with non-null genotype (3.86, 95%CI = 3.31–4.50 vs. 3.27, 95%CI = 2.83–3.78, P = 0.07) with adjustment of covariates. We also found that FA-exposed workers carrying GSTP1 Val allele had a slightly higher CBMN frequency compared with workers carrying only the wild-type allele (6.32 ± 3.78 vs. 5.01 ± 2.98, P = 0.05). Our results suggest that the FA exposure in this occupational population increased DNA and chromosome damages and polymorphisms in GSTs genes may modulate the genotoxic effects of FA exposure.     

Roles of composts in soil based on the assessment of humification degree of fulvic acids

This study was conducted to assess the humification degree in fulvic acids (FA) from different composts, and to reveal their roles after soil amending based on their excitation-emission matrices (EEM) of the fluorescence spectra and projection pursuit regression (PPR) analysis. Two peaks were detected in EEM spectra of FA from all composts, and three components were identified by the parallel factor analysis (PARAFAC) model. The assessment of the humification degree of FA using the ratios between the values of the percent fluorescence response in the visible and ultraviolet regions (P_I,n/P_II,n) generally agreed with that using the distributions of FA components (C1, C2 and C3). The PPR considering the parameters (P_I,n/P_II,n, C1, C2 and C3) further ranked the composts with similar of FA, and the FA humification degree decreased in the order: GW, TSW, LW and SW > CM, MSW, and PM > MC and KW. The results showed that the compositions of FA were similar to each other in composts from different materials, but there were distinct differences in the humification degree of FA owing to the different distributions of each component in composts. Therefore, based on the redistribution of components, a method for regulating the humification degree of FA during composting was presented. Furthermore, the suitable soil application of composts with different humification degrees was also demonstrated.     

Modulation of intracellular chloride channels by ATP and Mg2+

We report the effects of ATP and Mg²⁺ on the activity of intracellular chloride channels. Mitochondrial and lysosomal membrane vesicles isolated from rat hearts were incorporated into bilayer lipid membranes, and single chloride channel currents were measured. The observed chloride channels (n = 112) possessed a wide variation in single channel parameters and sensitivities to ATP. ATP (0.5–2 mmol/l) modulated and/or inhibited the chloride channel activities (n = 38/112) in a concentration-dependent manner. The inhibition effect was irreversible (n = 5/93) or reversible (n = 15/93). The non-hydrolysable ATP analogue AMP-PNP had a similar inhibition effect as ATP, indicating that phosphorylation did not play a role in the ATP inhibition effect. ATP modulated the gating properties of the channels (n = 6/93), decreased the channels' open dwell times and increased the gating transition rates. ATP (0.5–2 mmol/l) without the presence of Mg²⁺ decreased the chloride channel current (n = 12/14), whereas Mg²⁺ significantly reversed the effect (n = 4/4). We suggest that ATP-intracellular chloride channel interactions and Mg²⁺ modulation of these interactions may regulate different physiological and pathological processes.     

Predictive value of cystatin C and beta-2 microglobulin in preeclampsia

The purpose of this study was to determine whether the levels of cystatin C and beta-2 microglobulin (B2M) are altered during the second trimester in the plasma of women who subsequently develop preeclampsia.Study designWe performed a case control study to compare the levels of cystatin C and B2M in women in whom preeclampsia ultimately developed (n = 30) and in pregnant women who remained normotensive throughout gestation (n = 60). The maternal plasma levels of cystatin C and B2M were measured by enzyme-linked immunosorbent assay. Blood samples were collected between 15 and 20 weeks’ gestation for fetal aneuploidy screening and frozen at ?20 °C until assay after groups had been selected.ResultsThe median concentrations of cystatin C and B2M were significantly higher in those who subsequently developed preeclampsia when compared to those of normal pregnancy (median 668.6 ng/ml and 418.3 μg/ml vs 413.7 ng/ml and 321.2 μg/ml, respectively).ConclusionsIn this study, the maternal plasma levels of cystatin C and B2M were significantly elevated in pregnant women who subsequently developed preeclampsia as compared with normotensive women. Alterations of these proteins antedate clinical symptoms and, thus, they may be useful for early identification of patients at the risk of developing preeclampsia.     

Enhanced T cell responsiveness to Mycobacterium bovis BCG r32-kDa Ag correlates with successful anti-tuberculosis treatment in humans

Th1 and Th2 cytokines play key role in protection from and pathogenesis of mycobacterial infection and their dynamic changes may predict clinical outcome of the patient. Patients with tuberculosis (TB) have a poorer cellular immune response to recombinant 32-kDa antigen (Ag) of Mycobacterium bovis (r32-kDa M. bovis) than do healthy volunteers. The basis for this observation was studied by evaluating the Th1 (gamma interferon [IFN-γ]) produced in response to the r32-kDa Ag M. bovis by peripheral blood mononuclear cells (PBMC) from patients with pulmonary TB (n = 20), extra-pulmonary TB (n = 13) and from healthy volunteers (n = 9). Recombinant 32-kDa M. bovis stimulated PBMC from TB patients produced significantly lower levels of IFN-γ at 0 month, and increased at 2–4, and 6 months of treatment and were highly significant (p < 0.000) compared to the responses in controls. The ratios of IFN-γ to IL-10 were low in patients newly diagnosed and improved both during and after treatment. The present study concludes that the levels of in vitro response to M. bovis BCG r32-kDa Ag leading to the specific release of IFN-γ increased after anti-tuberculosis treatment and seems to reflect the clinical status of the patient, thus reiterating the utility of this antigen in T cell based assays as a surrogate marker of cell mediated responses.     

Milk fatty acid composition of dairy cows grazing at two pasture allowances and supplemented with different levels and sources of concentrate

Milk fatty acid (FA) composition of dairy cows from two grazing studies was examined. In the first study, effects of concentrate supplementation and pasture allowance were evaluated using 20 multiparous Holstein cows in five 4 × 4 Latin squares. The four treatments resulted from the combination of two pasture allowances (i.e., low, 25 versus high, 40 kg dry matter/cow/day) and two concentrate supplementation levels (i.e., 0 versus 1 kg concentrate/4 kg milk). No interactions occurred between concentrate supplementation and pasture allowance for milk FA composition. Concentrate supplementation increased short-chain FA content, and reduced the content of long-chain FA, trans11 C18:1, and cis9, trans11 conjugated linoleic acid (CLA) (1.36 versus 1.18 g/100 g). Concentrate supplementation increased saturated FA (58.6 versus 54.0 g/100 g) and reduced unsaturated FA content (39.9 versus 43.8 g/100 g). Grazing at high pasture allowance increased short-, medium-, and long-chain FA content, without affecting cis9, trans11 CLA content. Saturated FA content was higher (57.1 versus 55.6 g/100 g), and unsaturated FA content was lower (41.3 versus 42.5 g/100 g), when cows grazed at high pasture allowance. Concentrate supplementation reduced unsaturated FA and cis9, trans11 CLA in milk of dairy cows grazing at two pasture allowances. In the second study, two experiments evaluated effects of different energy supplements in grazing dairy cows. In Experiment 1, 25 multiparous Holstein cows were assigned to a cracked corn (CC) or a steam flaked corn (SFC) supplement containing 667 g/kg of corn grain plus a pelleted protein/mineral supplement. In Experiment 2, 22 multiparous Holstein cows were assigned to a ground corn grain (GC) or a non-forage fiber (NFF) supplement. The GC supplement contained 850 g/kg of corn grain, and the NFF supplement contained 440 g/kg of non-forage fiber sources (i.e., beet pulp, soyhulls, wheat middlings) that partially replaced corn grain. Milk FA composition was not affected by corn processing or carbohydrate source. The content of short-, medium-, long-chain FA, and cis9, trans11 CLA (2.5 g/100 g in Experiment 1; 2.1 g/100 g in Experiment 2) was similar between supplements in both experiments. The type of supplement did not affect the content of saturated (62.6 g/100 g in Experiment 1; 65.4 g/100 g in Experiment 2) and unsaturated FA (37.5 g/100 g in Experiment 1; 34.6 g/100 g in Experiment 2). Supplementation with supplements differing in the rate and extent of ruminal carbohydrate digestion did not affect the milk FA composition of grazing dairy cows.     

Association between periodontitis and common variants in the promoter of the interleukin-6 gene

We recently reported an association between interleukin-6 (IL6) polymorphisms (SNPs) and haplotypes and aggressive periodontitis (AgP). The aim of this study was to investigate this association in a larger cohort of subjects, affected by either aggressive or chronic periodontitis. Five IL6 SNPs were analyzed in 765 subjects (167 generalized aggressive periodontitis, 57 localized aggressive, 310 chronic periodontitis and 231 periodontally healthy). Among Caucasians (n = 454) there were moderate associations for ?1363T allele (p = 0.011) and for ?174GG and ?1363GG genotypes with diagnosis of periodontitis (respectively, p = 0.044, OR = 1.6, 95% CI = 1.0–2.4, and p = 0.017, OR = 1.8, 95% CI = 1.1–2.8, adjusted for age, gender and smoking). Haplotypes containing the ?174G>C, ?1363G>T and ?1480C>G polymorphisms were associated with diagnosis of periodontitis (p = 0.02). Subgroup analysis by disease phenotype showed associations for the localized AgP (LAgP) group and ?1480C>G and ?6106A>T SNPs (p = 0.007 and 0.010, respectively). Among Caucasians the genotypes IL6 ?1480 CC and ?6106 TT increased the adjusted OR for LAgP (OR = 3.09 and 2.27, respectively). This study supports the hypothesis that IL6 polymorphisms and haplotypes are moderately associated with periodontitis, possibly acting through influencing tissue levels of IL6. This association is stronger for LAgP than for other periodontal disease phenotypes.     

Opposite changes in cannabinoid CB1 and CB2 receptor expression in human gliomas

Gliomas are the most important group of malignant primary brain tumors and one of the most aggressive forms of cancer. During the last years, several studies have demonstrated that cannabinoids induce apoptosis of glioma cells and inhibit angiogenesis of gliomas in vivo. As the effects of cannabinoids rely on CB₁ and CB₂ receptors activation, the aim of the present study was to investigate both receptors protein expression in cellular membrane homogenates of human glial tumors using specific antibodies raised against these proteins. Additionally, we studied the functionality of the cannabinoid receptors in glioblastomas by using WIN 55,212-2 stimulated [³⁵S]GTPγS binding.Western blot analysis showed that CB₁ receptor immunoreactivity was significantly lower in glioblastoma multiforme (?43%, n = 10; p < 0.05) than in normal post-mortem brain tissue (n = 16). No significant differences were found for astrocytoma (n = 6) and meningioma (n = 8) samples. Conversely, CB₂ receptor immunoreactivity was significantly greater in membranes of glioblastoma multiforme (765%, n = 9; p < 0.05) and astrocytoma (471%, n = 4; p < 0.05) than in control brain tissue (n = 10). Finally, the maximal stimulation of [³⁵S]GTPγS binding by WIN 55,212-2 was significantly lower in glioblastomas (134 ± 4%) than in control membranes (183 ± 2%; p < 0.05). The basal [³⁵S]GTPγS binding and the EC₅₀ values were not significantly different between both groups.The present results demonstrate opposite changes in CB₁ and CB₂ receptor protein expression in human gliomas. These changes may be of interest for further research about the therapeutic effects of cannabinoids in glial tumors.     

Breast cancer risk and common single nucleotide polymorphisms in homologous recombination DNA repair pathway genes XRCC2, XRCC3, NBS1 and RAD51

The possible role for DNA repair deficiencies in cancer development, namely in breast cancer has been the subject of increasing interest since it has been reported that breast cancer patients might be deficient in the repair of DNA damage. Exposure to ionizing radiation has been pointed out as a risk factor for breast cancer, and the type of DNA lesions induced by this carcinogen can be repaired by homologous recombination DNA repair (HRR) pathway. To evaluate the potential modifying role of some single nucleotide polymorphisms (SNP) in HRR involved genes on the individual susceptibility to breast cancer we carried out a hospital based case–control study in a Caucasian Portuguese population (289 histological confirmed breast cancer patients and 548 control individuals). We genotyped 4 SNPs in 4 different HRR pathway genes, XRCC2 (Ex3 + 442G > A, R188H, rs3218536), XRCC3 (Ex8-5C > T, T241M, rs861539), NBS1 (Ex5-32C > G, E185Q, rs1805794) and RAD51 5′UTR (Ex1-59G > T, rs1801321), tagging 41 SNPs in these genes. The frequency of the different polymorphisms in the Portuguese control population is similar to the ones reported for other Caucasian populations, and the deviation of the Hardy–Weinberg equilibrium was only observed for the XRCC2 (Ex3 + 442G > A, R188H, rs3218536) polymorphism in the control population. The results obtained, after logistic regression analysis, did not reveal a major role of these polymorphisms on breast cancer susceptibility. However, when the population was stratified according to breast feeding (women that breast fed and women that never breast fed) it is observed, in women that never breast fed, that the heterozygous individuals for the XRCC2 (Ex3 + 442G > A, R188H, rs3218536) polymorphism have a decreased risk for breast cancer [adjusted OR = 0.45; 95% CI = 0.22–0.92] (P = 0.03). Additionally, after stratification according to menopausal status, our results suggest that post-menopausal women carrying at least one variant allele for the XRCC3 (Ex8-5C > T, T241M, rs861539) polymorphism have a lower risk for breast cancer [adjusted OR = 0.67; 95% CI, 0.47–0.94] (P = 0.03). Most of the studies suggest that breastfeeding may be responsible for 2/3 of the estimate reduction of breast cancer. The longer the duration of breastfeeding the lower the potential risk associated with breast cancer. Therefore, in our study the potential protective role of the variant allele of XRCC2 (Ex3 + 442G > A, R188H, rs3218536), in never breast fed women, might be related with a more efficient DNA repair activity.     

Revealing the three dimensional architecture of focal adhesion components to explain Ca2 +-mediated turnover of focal adhesions

BackgroundFocal adhesions (FAs) are large, dynamic protein complexes located close to the plasma membrane, which serve as the mechanical linkages and a biochemical signaling hub of cells. The coordinated and dynamic regulation of focal adhesion is required for cell migration. Degradation, or turnover, of FAs is a major event at the trailing edge of a migratory cell, and is mediated by Ca^2 +/calpain-dependent proteolysis and disassembly. Here, we investigated how Ca^2 + influx induces cascades of FA turnover in living cells.MethodsImages obtained with a total internal reflection fluorescence microscope (TIRFM) showed that Ca^2 + ions induce different processes in the FA molecules focal adhesion kinase (FAK), paxillin, vinculin, and talin. Three mutated calpain-resistant FA molecules, FAK-V744G, paxillin-S95G, and talin-L432G, were used to clarify the role of each FA molecule in FA turnover.ResultsVinculin was resistant to degradation and was not significantly affected by the presence of mutated calpain-resistant FA molecules. In contrast, talin was more sensitive to calpain-mediated turnover than the other molecules. Three-dimensional (3D) fluorescence imaging and immunoblotting demonstrated that outer FA molecules were more sensitive to calpain-mediated proteolysis than internal FA molecules. Furthermore, cell contraction is not involved in degradation of FA.ConclusionsThese results suggest that Ca^2 +-mediated degradation of FAs was mediated by both proteolysis and disassembly. The 3D architecture of FAs is related to the different dynamics of FA molecule degradation during Ca^2 +-mediated FA turnover.General significanceThis study will help us to clearly understand the underlying mechanism of focal adhesion turnover by Ca^2 +.     

Fatty acid and nutritive quality of chia (Salvia hispanica L.) seeds and plant during growth

The fatty acid (FA) profile, chemical composition, gross energy and organic matter digestibility of chia (Salvia hispanica L.) have been determined in the seed and in the plant collected at five progressive morphological stages from early vegetative to budding stage. The FA analyses disclosed quantitative differences between the plant stages that were characterised by a high percentage of polyunsaturated fatty acids (PUFA), which made up from 752 to 623 g/kg of the total FA of the plant during the growth cycle. The α-linolenic acid (ALA, C_18:3n–3) decreased from 649 g/kg, at the early vegetative stage, to 499 g/kg of the total FA, at the budding stage, while all the other FAs increased with increasing growth stage. The chia seed FAs were also highly unsaturated, with their main components being ALA (641 g/kg of the total FA) and linoleic acid (LA, C_18:2n–6; 188 g/kg of the total FA).The evolution of the quality of chia is closely related to the ageing of the plant. The chia plant provides a forage with a good nutritive value when harvested at a stage before the shooting period. After this, the nutritional quality of the plant considerably decreases with an increase in the fibrous fractions and a dramatical decrease of the crude protein content.     

Synthesis,spectral and magnetical characterization of monomeric [Cu(2-NO2bz)2(3-pyme)2(H2O)2] and polymeric [Cu{3,5-(NO2)2bz}2(3-pyme)2]n

Two new complexes of composition [Cu(2-NO₂bz)₂(3-pyme)₂(H₂O)₂] (1) and/or [Cu{3,5-(NO₂)₂bz}₂(3-pyme)₂] (2) (3-pyme = 3-pyridylmethanol, ronicol or 3-pyridylcarbinol, 2-NO₂bz = 2-nitrobenzoate and 3,5-(NO₂)₂bz = 3,5-dinitrobenzoate) have been prepared and studied by elemental analysis, electronic, infrared and EPR spectroscopy, magnetic susceptibility measurements and the structure of both complexes has been solved. Complex (1) shows an unusual molecular type of structure consisting of the [Cu(2-NO₂bz)₂(3-pyme)₂(H₂O)₂] molecules held together by hydrogen bonds and van der Waals interactions. Complex (2) exhibits a polymeric chain-like structure [Cu{3,5-(NO₂)₂bz}₂(3-pyme)₂]_n with copper atoms doubly bridged by two 3-pyridylmethanol molecules and the polymeric molecules are held together by van der Waals interactions. Complex (1) exhibits a magnetic moment μ_eff = 1.84 B.M. at 300 K that remains nearly constant within the temperature region (5–300 K). Further cooling results in lowering the magnetic moment to μ_eff = 1.82 B.M. at 1.8 K. The magnetic susceptibility temperature dependence obeys Curie–Weiss law with Curie constant of 0.423 cm³ K mol⁻¹ and with Weiss constant of −0.06 K. The magnetic moment of (2) exhibits a small increase with a decrease in the temperature (μ_eff = 1.80 B.M. at 300 K and μ_eff = 1.85 B.M. at 1.8 K) with Curie constant of 0.409 cm³ K mol⁻¹ and with Weiss constant of +1.1 K, which can indicate a very weak ferromagnetic interaction between the copper atoms within the chain. Applying the molecular field model resulted in obtaining zJ′ values −0.08 cm⁻¹ for complex (1), and −0.07 cm⁻¹ for complex (2), respectively, that could characterize intermolecular and interchain interactions transmitted through π–π stacking.     

Liquid chromatography–tandem mass spectrometry assay for the quantification of free and total sialic acid in human cerebrospinal fluid

BackgroundAnalysis of sialic acid (SA) metabolites in cerebrospinal fluid (CSF) is important for clinical diagnosis. In the present study, a high-performance liquid chromatography–tandem mass spectrometry (HPLC/MS/MS) method for free sialic acid (FSA) and total sialic acid (TSA) in human CSF was validated.MethodsThe method utilized a simple sample-preparation procedure of protein precipitation for FSA and acid hydrolysis for TSA. Negative electrospray ionisation was used to monitor the transitions m/z 308.2 → 87.0 (SA) and m/z 311.2 → 90.0 (¹³C₃-SA). Conjugated sialic acid (CSA) was calculated by subtracting FSA from TSA. We established reference intervals for FSA, TSA and CSA in CSF in 217 control subjects. The method has been applied to patients’ samples with known differences in SA metabolites like meningitis (n = 6), brain tumour (n = 2), leukaemia (n = 5), and Salla disease (n = 1).ResultsLimit of detection (LOD) was 0.54 μM for FSA and 0.45 μM for TSA. Intra- and inter-assay variation for FSA (21.8 μM) were 4.8% (n = 10) and 10.4% (n = 40) respectively. Intra- and inter-assay variation for TSA (35.6 μM) were 9.7% (n = 10) and 12.8% (n = 40) respectively. Tested patients showed values of TSA above established reference value.ConclusionThe validated method allows sensitive and specific measurement of SA metabolites in CSF and can be applied for clinical diagnoses.     

Comparing anti-HIV,antibacterial, antifungal,micellar, and cytotoxic properties of tricarboxylato dendritic amphiphiles

Three series of homologous dendritic amphiphiles—RCONHC(CH₂CH₂COOH)₃, 1(n); ROCONHC(CH₂CH₂COOH)₃, 2(n); RNHCONHC(CH₂CH₂COOH)₃, 3(n), where R = n-C_nH_2n+1 and n = 13–22 carbon atoms—were assayed for their potential to serve as antimicrobial components in a topical vaginal formulation. Comparing epithelial cytotoxicities to the ability of these homologues to inhibit HIV, Neisseria gonorrhoeae, and Candida albicans provided a measure of their prophylactic/therapeutic potential. Measurements of the ability to inhibit Lactobacillus plantarum, a beneficial bacterium in the vagina, and critical micelle concentrations (CMCs), an indicator of the potential detergency of these amphiphiles, provided additional assessments of safety. Several amphiphiles from each homologous series had modest anti-HIV activity (EC₅₀ = 110–130 μM). Amphiphile 2(18) had the best anti-Neisseria activity (MIC = 65 μM), while 1(19) and 1(21) had MICs against C. albicans of 16 and 7.7 μM, respectively. Two measures of safety showed promise as all compounds had relatively low cytotoxic activity (EC₅₀ = 210–940 μM) against epithelial cells and low activity against L. plantarum, 1(n), 2(n), and 3(n) had MICs ? 490, 1300, and 940 μM, respectively. CMCs measured in aqueous triethanolamine and in aqueous potassium hydroxide showed linear dependences on chain length. As expected, the longest chain in each series had the lowest CMC—in triethanolamine: 1(21), 1500 μM; 2(22), 320 μM; 3(22), 340 μM, and in potassium hydroxide: 1(21), 130 μM; 3(22), 40 μM. The CMC in triethanolamine adjusted to pH 7.4 was 400 μM for 1(21) and 3900 μM for 3(16). The promising antifungal activity, low activity against L. plantarum, relatively high CMCs, and modest epithelial cytotoxicity in addition to their anti-Neisseria properties warrant further design studies with dendritic amphiphiles to improve their safety indices to produce suitable candidates for antimicrobial vaginal products.     

Design,synthesis and characterization of novel 1,2-benzisothiazol-3(2H)-one and 1,3,4-oxadiazole hybrid derivatives: Potent inhibitors of Dengue and West Nile virus NS2B/NS3 proteases

1,2-Benzisothiazol-3(2H)-ones and 1,3,4-oxadiazoles individually have recently attracted considerable interest in drug discovery, including as antibacterial and antifungal agents. In this study, a series of functionalized 1,2-benzisothiazol-3(2H)-one—1,3,4-oxadiazole hybrid derivatives were synthesized and subsequently screened against Dengue and West Nile virus proteases. Ten out of twenty-four compounds showed greater than 50% inhibition against DENV2 and WNV proteases ([I] = 10 μM). The IC₅₀ values of compound 7n against DENV2 and WNV NS2B/NS3 were found to be 3.75 ± 0.06 and 4.22 ± 0.07 μM, respectively. The kinetics data support a competitive mode of inhibition by compound 7n. Molecular modeling studies were performed to delineate the putative binding mode of this series of compounds. This study reveals that the hybrid series arising from the linking of the two scaffolds provides a suitable platform for conducting a hit-to-lead optimization campaign via iterative structure–activity relationship studies, in vitro screening and X-ray crystallography.     

Modeling kinetics of ammonium oxidation and nitrite oxidation under simultaneous inhibition by free ammonia and free nitrous acid

Inhibition of ammonium oxidation and nitrite oxidation by free ammonia (FA) and free nitrous acid (FNA) was studied using three different sludges. An uncompetitive inhibition model fit the experimental data well when the reactions were under FA inhibition, whereas a noncompetitive model fit well under FNA inhibition. The estimates of the inhibition constant (K_I) of nitrite oxidation were 46 μM for FA and 1.7–6.8 μM for FNA, each of which was significantly smaller than that of ammonium oxidation, which were 290–1600 μM for FA and 12 μM for FNA. The much smaller values of K_I for nitrite oxidation reflected the susceptibility of that reaction to inhibition by FA and FNA, which could lead to accumulation of nitrite during nitrification. A kinetic model for simultaneous inhibition by FA and FNA was derived. The model predicted that nitrite oxidation should be affected more seriously than ammonium oxidation by the simultaneous inhibition, which would accelerate the accumulation of nitrite in a strong nitrogenous wastewater treatment. It also indicated that a complete removal of ammonia could be achieved with high accumulation of nitrite in a sequencing batch reactor, which is impossible in a continuous-flow reactor.     

FGFR3 mutational status and protein expression in patients with bladder cancer in a Jordanian population

Bladder cancer accounts for nearly 5% of all newly diagnosed cancers in Jordan, with a much higher frequency in males. Recent studies have shown that activating mutations in FGFR3 are the most common findings in non-invasive low grade bladder tumors. In this study, we, retrospectively, investigated a cohort of 121 bladder cancer patients with various grades and stages of the tumor for molecular changes in FGFR3. Overexpression of FGFR3 was observed in 49%, 34%, 15%, and 2% of pTa, pT1, pT2, and pT3 cases, respectively. Further, FGFR3 expression was positive in 45%, 26%, and 30% of G1, G2 and G3 cases, respectively. Mutational analysis of exons 7, 10 and 15 of FGFR3 identified four previously reported mutations, namely R248C (n = 4; 10%), S249C (n = 23; 59%), Y375C (n = 7; 18%), G382R (n = 4; 10%), and one novel mutation, G382E (n = 1; 3%). Our results indicate that both mutations and overexpression of FGFR3 are correlated together, and are more prevalent in early stage (pTa and pT1) and low grade (G1 and G2) bladder tumors. Survival analysis showed no contribution of changes in FGFR3 on the patient's survival. Multivariate Cox proportional hazards model analysis of overall survival for the following variables: age, gender, stage and grade of tumor, and FGFR3 (expression and mutation) revealed that age, stage and grade of tumor are independent predictors of overall survival in patients with bladder cancer. Our work is the first to address the molecular status of FGFR3 in Jordanian patients with bladder cancer, and provides further support for FGFR3 as a key player in the initiation of bladder tumors.     

Improved reproducibility in the determination of the molecular weight of chitosan by analytical size exclusion chromatography

The reproducibility of the determination of the molecular weight of chitosans in the 90–210 kDa range (M_n) by analytical size exclusion chromatography with multi-angle laser light scattering (SEC-MALLS) was improved by reducing the salt concentration in the mobile phase from (0.3 M acetic acid, 0.2 M sodium acetate, and 0.8 mM sodium azide) to (0.15 M acetic acid, 0.1 M sodium acetate, and 0.4 mM sodium azide) using Tosoh TSKgel G6000PW_XL and G5000PW_XL columns in series. The variability of measured molecular weight was significantly reduced by lowering the acetate concentration in the mobile phase, while the average molecular weight did not change significantly. The coefficient of variation of the number-average molecular weight, CV(M_n), decreased from 7–12% to 3–6% upon mobile phase dilution. This reduced variability in molecular weight of chitosans obtained from SEC is a significant improvement when precise values of chitosan molecular weight are required, for example in stability studies where viscosity changes in concentrated chitosan solutions are assessed, and in gene delivery applications.