Thyroid hormones (THs) are major regulators of biological processes essential for correct development and energy homeostasis. Although thyroid disruptors can deeply affect human health, the impact of ...exogenous chemicals and in particular mixture of chemicals on different aspects of thyroid development and metabolism is not yet fully understood. In this study we have used the highly versatile zebrafish model to assess the thyroid axis disrupting effects of cadmium (Cd) and dibenzothiophene (DBT), two environmental endocrine disruptors found to be significantly correlated in epidemiological co-exposure studies. Zebrafish embryos (5hpf) were exposed to low concentrations of Cd (from 0.05 to 2 μM) and DBT (from 0.05 to 1 μM) and to mixtures of them. A multilevel assessment of the pollutant effects has been obtained by combining in vivo morphological analyses allowed by the use of transgenic fluorescent lines with liquid chromatography mass spectrometry determination of TH levels and quantification of the expression levels of key genes involved in the Hypothalamic-Pituitary-Thyroid Axis (HPTA) and TH metabolism. Our results underscore for the first time an important synergistic toxic effect of these pollutants on embryonic development and thyroid morphology highlighting differences in the mechanisms through which they can adversely impact on multiple physiological processes of the HPTA and TH disposal influencing also heart geometry and function.
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•Dibenzothiophene (DBT) synergizes with Cadmium (Cd) in inducing zebrafish morphological defects.•Low DBT and Cd concentrations impact thyroid development and homeostasis through different mechanisms.•DBT-Cd mix induces a dose-dependent increase of thyroid hormone receptor expression.•Low DBT and Cd slightly impact cardiac development but triggers hypothyroid-like bradycardia.
Chronic lymphocytic leukemia (CLL) is a progressive malignancy of mature B-cells that involves the peripheral blood (PB), lymph nodes (LNs) and bone marrow (BM). Although the majority of CLL cells ...are in a resting state, small populations of proliferating cells exist; however, the anatomical site of active cell proliferation remains to be definitively determined. Based on findings that CLL cells in LNs have increased expression of B-cell activation genes, we tested the hypothesis that the fraction of 'newly born' cells would be highest in the LNs. Using a deuterium oxide (
H) in vivo labeling method in which patients consumed deuterated (heavy) water (
H
O), we determined CLL cell kinetics in concurrently obtained samples from LN, PB and BM. The LN was identified as the anatomical site harboring the largest fraction of newly born cells, compared to PB and BM. In fact, the calculated birth rate in the LN reached as high a 3.3% of the clone per day. Subdivision of the bulk CLL population by flow cytometry identified the subpopulation with the CXCR4
CD5
phenotype as containing the highest proportion of newly born cells within each compartment, including the LN, identifying this subclonal population as an important target for novel treatment approaches.
Abstract
We aimed to isolate
Acinetobacter baumannii
(
A. baumannii
) from wound infections, determine their resistance and virulence profile, and assess the impact of Silver nanoparticles (AgNPs) on ...the bacterial growth, virulence and biofilm-related gene expression. AgNPs were synthesized and characterized using TEM, XRD and FTIR spectroscopy.
A. baumannii
(n = 200) were isolated and identified. Resistance pattern was determined and virulence genes (
afa/draBC, cnf1, cnf2, csgA, cvaC, fimH, fyuA, ibeA, iutA, kpsMT II, PAI, papC, PapG II, III, sfa/focDE
and
traT)
were screened using PCR. Biofilm formation was evaluated using Microtiter plate method. Then, the antimicrobial activity of AgNPs was evaluated by the well-diffusion method, growth kinetics and MIC determination. Inhibition of biofilm formation and the ability to disperse biofilms in exposure to AgNPs were evaluated. The effect of AgNPs on the expression of virulence and biofilm-related genes (
bap, OmpA, abaI, csuA/B, A1S_2091, A1S_1510, A1S_0690, A1S_0114
) were estimated using QRT-PCR. In vitro infection model for analyzing the antibacterial activity of AgNPs was done using a co-culture infection model of
A. baumannii
with human fibroblast skin cell line HFF-1 or Vero cell lines.
A. baumannii
had high level of resistance to antibiotics. Most of the isolates harbored the
fimH
,
afa/draBC
,
cnf1
,
csgA
and
cnf2,
and the majority of
A. baumannii
produced strong biofilms. AgNPs inhibited the growth of
A. baumannii
efficiently with MIC ranging from 4 to 25 µg/ml.
A. baumannii
showed a reduced growth rate in the presence of AgNPs. The inhibitory activity and the anti-biofilm activity of AgNPs were more pronounced against the weak biofilm producers. Moreover, AgNPs decreased the expression of
kpsMII
,
afa/draBC,bap, OmpA,
and
csuA/B
genes. The in vitro infection model revealed a significant antibacterial activity of AgNPs against extracellular and intracellular
A. baumannii
. AgNPs highly interrupted bacterial multiplication and biofilm formation. AgNPs downregulated the transcription level of important virulence and biofilm-related genes. Our findings provide an additional step towards understanding the mechanisms by which sliver nanoparticles interfere with the microbial spread and persistence.
Ibrutinib and other targeted inhibitors of B-cell receptor signaling achieve impressive clinical results for patients with chronic lymphocytic leukemia (CLL). A treatment-induced rise in absolute ...lymphocyte count (ALC) has emerged as a class effect of kinase inhibitors in CLL and warrants further investigation. Here we report correlative studies in 64 patients with CLL treated with ibrutinib. We quantified tumor burden in blood, lymph nodes (LNs), spleen and bone marrow, assessed phenotypic changes of circulating cells and measured whole-blood viscosity. With just one dose of ibrutinib, the average increase in ALC was 66%, and in>40% of patients the ALC peaked within 24 h of initiating treatment. Circulating CLL cells on day 2 showed increased Ki67 and CD38 expression, indicating an efflux of tumor cells from the tissue compartments into the blood. The kinetics and degree of the treatment-induced lymphocytosis was highly variable; interestingly, in patients with a high baseline ALC the relative increase was mild and resolution rapid. After two cycles of treatment the disease burden in the LN, bone marrow and spleen decreased irrespective of the relative change in ALC. Whole-blood viscosity was dependent on both ALC and hemoglobin. No adverse events were attributed to the lymphocytosis.
We report on an active nanocarrier for chlorhexidine (CHX) based on sterically stabilized shellac nanoparticles (NPs) with dual surface functionalization, which greatly enhances the antimicrobial ...action of CHX. The fabrication process for the CHX nanocarrier is based on pH-induced co-precipitation of CHX-DG from an aqueous solution of ammonium shellac and Poloxamer 407 (P407), which serves as a steric stabilizing agent. This is followed by further surface modification with octadecyl trimethyl ammonium bromide (ODTAB) through a solvent change to yield cationic surface functionality. In this study, we assessed the encapsulation efficiency and release kinetics of the novel nanocarrier for CHX. We further examined the antimicrobial effects of the CHX nanocarriers and their individual components in order to gain better insight into how they work, to improve their design and to explore the impacts of their dual functionalization. The antimicrobial actions of CHX loaded in shellac NPs were examined on three different proxy microorganisms: a Gram-negative bacterium (
), a yeast (
) and a microalgae (
). The antimicrobial actions of free CHX and CHX-loaded shellac NPs were compared over the same CHX concentration range. We found that the non-coated shellac NPs loaded with CHX showed inferior action compared with free CHX due to their negative surface charge; however, the ODTAB-coated, CHX-loaded shellac NPs strongly amplified the antimicrobial action of the CHX for the tested microorganisms. The enhancement of the CHX antimicrobial action was thought to be due to the increased electrostatic adhesion between the cationic surface of the ODTAB-coated, CHX-loaded shellac NPs and the anionic surface of the cell walls of the microorganisms, ensuring direct delivery of CHX with a high concentration locally on the cell membrane. The novel CHX nanocarriers with enhanced antimicrobial action may potentially find applications in dentistry for the development of more efficient formulations against conditions such as gingivitis, periodontitis and other oral infections, as well as enabling formulations to have lower CHX concentrations.
The lymph node (LN) is the site of chronic lymphocytic leukemia (CLL) cell activation and proliferation. Aberrant microRNA (miRNA) expression has been shown to have a role in CLL pathogenesis; ...however, a comparison of miRNA expression between CLL cells in the LN and the peripheral blood (PB) has previously not been reported. On the basis of the analysis of 17 paired LN and PB samples from CLL patients, we identify a panel of miRNAs that are increased in LN CLL cells correlating with an activation phenotype. When evaluated in CLL cells from 38 patients pre and post treatment with ibrutinib, a subset of these miRNAs (miR-22, miR-34a, miR-146b and miR-181b) was significantly decreased in response to ibrutinib. A concomitant increase in putative miRNA target transcripts (ARID1B, ARID2, ATM, CYLD, FOXP1, HDAC1, IBTK, PTEN and SMAD4) was also observed. Functional studies confirmed targets of ibrutinib-responsive miRNAs to include messenger RNA transcripts of multiple tumor suppressors. Knockdown of endogenous miR-34a and miR146b resulted in increased transcription of tumor suppressors and inhibition of cell proliferation. These findings demonstrate that ibrutinib downregulates the expression of a subset of miRNAs related to B-cell activation leading to increased expression of miRNA targets including tumor suppressors and a reduction in cell proliferation.
We investigate the effect of nonthermal electrons modeled by two non-Maxwellian distribution functions, i.e., the (r, q) and Cairn’s distributions on the formation of dust acoustic (DA) solitons in ...an un-magnetized dusty plasma by incorporating the effect of dust streaming. We adopt the pseudopotential technique to obtain solitary wave solutions from fluid equations. It is seen that only rarefactive soliton can be obtained in such plasmas where ions are considered Boltzmannian and electrons non-Maxwellian. We find that soliton characteristics are strongly dependent on the nonthermal spectral indices r, q, and α and dust temperature Td. For (r, q) distribution, it is found that soliton amplitude increases but width decreases when the positive (negative) value of r decreases (increases). For Cairn’s distribution, we find that with the increase in α, soliton amplitude decreases. In space environments, such as cometary tails, solar wind, and Earth’s magnetosphere, where non-Maxwellian populations of electrons are present, our theoretical results show that the amplitude of soliton remains smaller than the Maxwellian case. Thus, Maxwellian distribution overestimates the soliton amplitude in such space environments. Therefore, we feel that our results will better interpret the results of observations, from cometary tails, and other space plasmas where nonlinear DA structures are likely to be observed.
Nodal extracapsular extension (ECE) in patients with head-and-neck cancer increases the loco-regional failure risk and is an indication for adjuvant chemoradiation therapy (CRT). To reduce the risk ...of requiring trimodality therapy, patients with head-and-neck cancer who are surgical candidates are often treated with definitive CRT when preoperative computed tomographic imaging suggests radiographic ECE. The purpose of this study was to assess the accuracy of preoperative CT imaging for predicting pathologic nodal ECE (pECE).
The study population consisted of 432 consecutive patients with oral cavity or locally advanced/nonfunctional laryngeal cancer who underwent preoperative CT imaging before initial surgical resection and neck dissection. Specimens with pECE had the extent of ECE graded on a scale from 1 to 4.
Radiographic ECE was documented in 46 patients (10.6%), and pECE was observed in 87 (20.1%). Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were 43.7%, 97.7%, 82.6%, and 87.3%, respectively. The sensitivity of radiographic ECE increased from 18.8% for grade 1 to 2 ECE, to 52.9% for grade 3, and 72.2% for grade 4. Radiographic ECE criteria of adjacent structure invasion was a better predictor than irregular borders/fat stranding for pECE.
Radiographic ECE has poor sensitivity, but excellent specificity for pECE in patients who undergo initial surgical resection. PPV and NPV are reasonable for clinical decision making. The performance of preoperative CT imaging increased as pECE grade increased. Patients with resectable head-and-neck cancer with radiographic ECE based on adjacent structure invasion are at high risk for high-grade pECE requiring adjuvant CRT when treated with initial surgery; definitive CRT as an alternative should be considered where appropriate.
Recently, the extensive use of quinolones led to increased resistance to these antimicrobial agents, with different rates according to the organism and the geographical region. The aim of this study ...was to detect the resistance rate of
Iraqi isolates toward quinolone antimicrobial agents, to determine genetic mutations in
and
, to screen for efflux-pump activity, and to screen the presence of plasmid-mediated quinolone resistance (PMQR) genes.
Forty-three
isolates were confirmed phenotypically and genotypically by Vitek 2 system and species specific primers by PCR using the targeting
gene followed by sequencing. Antibiotic susceptibility test was carried out using disc diffusion method. Quinolone resistant isolates were subjected to ciprofloxacin MIC testing, and cartwheel method to screen for efflux pump activity. The presence of the plasmid mediated quinolone resistance genes
, and
was tested by PCR. Sequencing of
A and
C was performed.
We observed a high rate of resistance to ceftriaxone, gentamicin ciprofloxacin, and levofloxacin. Low rate of resistance was detected against amikacin and azithromycin. Ciprofloxacin MIC results revealed that 96.1% of the isolates had MICs >256 µg/mL, 83.4% had MICs >512 µg/mL while 34.6% had MIC >1024 µg/mL. Testing of isolates against ciprofloxacin mixed with EtBr at various concentrations resulted in decreased resistant. Sequencing results showed that Ser83Leu was the most common mutation in
A that was observed in all quinolone resistant isolates, followed by Asp87Asn. Ser80Ile mutation in
C was observed in 77.7% of the tested isolates. The prevalence of PMQR genes was 92.5%
, 51.8%
B, 40.7%
A, and 37%
S.
Quinolone resistance is common in
isolates in Baghdad. The frequent mutation in
A and
C, and the presence of PMQR genes is alarming.
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