Relation between interleukin-13 and annexin-V levels and carotid intima-media thickness in nephrotic syndrome.

Background and aim: The aim of the current study is to assess the relation between carotid intima-media thickness (CIMT) measurements, renal Doppler resistive index (RI) and serum levels of interleukin-13 (IL-13) and annexin-V (An-V) in children with idiopathic nephrotic syndrome (INS). Materials and methods: The present case-control study was conducted on 60 children with INS and 60 age- and sex-matched healthy children. All participants were subjected to evaluation of serum levels of IL-13 and An-V and ultrasound Doppler measurement of CIMT and renal RI. Results: Patients expressed significantly higher An-V (5.9 ± 2.6 vs. 2.1 ± 0.8 ng/mL, p<0.001) and IL-13 (19.2 ± 7.6 vs. 3.4 ± 1.4 ng/L) levels when compared with healthy counterparts. Moreover, it was shown that patients had significantly higher CIMT (0.49 ± 0.06 vs. 0.35 ± 0.03, p<0.001) as compared to controls. No significant differences were noted between the studied groups regarding right or left RIs. Correlation analysis identified significant direct correlation between serum An-V levels and albumin/creatinine ratio (ACR) (r = 0.55), cholesterol (r = 0.48), triglycerides (r = 0.36), IL-13 (r = 0.92) and CIMT (r = 0.53). Similar correlations could be found between serum IL-13 levels and CIMT measurements and the corresponding parameters. Conclusions: The present study suggests an association between higher early atherosclerosis expressed as elevated CIMT measurements in children with INS and elevated serum levels of An-V and IL-13.

Arg-biodynamers as antibiotic potentiators through interacting with Gram-negative outer membrane lipopolysaccharides.

Antimicrobial resistance is becoming more prominent day after day due to a number of mechanisms by microbes, especially the sophisticated biological barriers of bacteria, especially in Gram-negatives. There, the lipopolysaccharides (LPS) layer is a unique component of the outer leaflet of the outer membrane which is highly impermeable and prevents antibiotics from passing passively into the intracellular compartments. Biodynamers, a novel class of dynamically bio-responsive polymers, may open new perspectives to overcome this particular barrier by accommodating various secondary structures and form supramolecular structures in such bacterial microenvironments. Generally, bio-responsive polymers are not only candidates as bio-active molecules against bacteria but also carriers via their interactions with the cargo. Based on their dynamicity, design flexibility, biodegradability, biocompatibility, and pH-responsiveness, we investigated the potential of two peptide-based biodynamers for improving antimicrobial drug delivery. By a range of experimental methods, we discovered a greater affinity of Arg-biodynamers for bacterial membranes than for mammalian membranes as well as an enhanced LPS targeting on the bacterial membrane, opening perspectives for enhancing the delivery of antimicrobials across the Gram-negative bacterial cell envelope. This could be explained by the change of the secondary structure of Arg-biodynamers into a predominant ß-sheet character in the LPS microenvironment, by contrast to the α-helical structure typically observed for most lipid membrane-permeabilizing peptides. In comparison to poly-L-arginine, the intrinsic antibacterial activity of Arg-biodynamers was nearly unchanged, but its toxicity against mammalian cells was >128-fold reduced. When used in bacterio as an antibiotic potentiator, however, Arg-biodynamers improved the minimum inhibitory concentration (MIC) against Escherichia coli by 32 times compared to colistin alone. Similar effect has also been observed in two stains of Pseudomonas aeruginosa. Arg-biodynamers may therefore represent an interesting option as an adjuvant for antibiotics against Gram-negative bacteria and to overcome antimicrobial resistance.

Two versus three doses of COVID-19 vaccine and post-vaccination COVID-19 infection in hemodialysis patients.

Background and aim: Patients with chronic kidney disease including those undergoing hemodialysis (HD) constitute a particularly challenging group regarding COVID-19 vaccination. The present study aimed to compare the rate of reinfection after two and three doses of Sinopharm COVID-19 vaccine in HD patients. Patients and methods: The study included 80 HD patients who received three doses of Sinopharm COVID-19 vaccine. In addition, there were another 80 patients who received only two doses of the vaccine. Patients in the latter group were selected based on propensity matching score with 1:1 ratio. Patients were monitored for post-vaccination COVID-19 infection using PCR examination of nasopharyngeal swabs. Patients were also monitored for post-vaccination complications including general complaints (headache, fever, fatigue), injection site complaints (arm pain, swelling, itching, rash), musculoskeletal complaints (muscle spasm or pain, joint pain) and others. All patients were followed for six months. Results: The present study included 80 patients submitted to COVID-19 vaccination with two doses of Sinopharm vaccine (GI) and other 80 patients who received three doses of the same vaccine (GII). At the end of follow up, 11 patients (13.8 %) in GI caught COVID-19 infection. In contrast, no patient in GII had infection (P<0.001). Comparison between patients who had COVID-19 infection and those without infection revealed that the former subgroup had significantly lower BMI (23.3 ± 2.3 versus 27.5 ± 8.1 Kg/m2), higher frequency of associated Hepatitis C (HCV) infection (54.6 % versus 2.9 %, P<0.001) and higher serum ferritin levels [median (IQR): 1101.0 (836.0-1564.0) versus 675.0 (467.0-767.7) ng/mL, P=0.01]. Binary logistic regression analysis identified high serum ferritin levels [OR (95% CI): 0.014 (0.001-0.15), P<0.001] and associated HCV infection [OR (95% CI): 0.99 (0.98-1.01), P=0.02] as significant predictors of post-vaccination COVID-19 infection in multivariate analysis. Conclusions: A three dose regime of Sinopharm COVID-19 vaccine associated with significantly lower rate of reinfection COVID-19 infection in HD patients. Infected patients had significantly lower BMI, higher frequency of HCV and higher ferritin levels.

Clinical and prognostic significance of CD27 and CD44 expression patterns in Egyptian pediatric patients with B-precursor acute lymphoblastic leukemia.

INTRODUCTION: The expression pattern of CD27 and CD44 was found to correlate with the differentiation stages of B cell precursors, which were known to be involved in a variety of immunological responses. AIM OF THE STUDY: This study aimed to determine the biological significance of CD27 and CD44 expression in patients with B-precursor acute lymphoblastic leukemia (B-ALL), as well as their association with standard prognostic factors and therapeutic response. PATIENTS AND METHODS: This case-control study included 60 pediatric patients newly diagnosed with B-ALL and 30 pediatric controls. The patient CD27 and CD44 levels were measured using the Beckman Coulter Navios Flow Cytometer. RESULTS: Most malignant cells (91.6 %) expressed CD44, but only 50 % of the patients had CD27 expressed. The positive CD 44 expression was associated with unfavorable prognostic markers, including a decrease.

Soluble CD163 impact as a prognostic biomarker in chronic lymphocytic leukemia.

Chronic lymphocytic leukemia (CLL) is a malignant blood disorder in which there is an excess of white blood cells (lymphocytes) in blood and lymphoid tissues. CLL patients experience different clinical behaviors with diversity in disease course and outcome. Accordingly, prognostic markers are crucial for employing appropriate therapy protocols. CD163 (cluster of differentiation 163) is a monocyte/macrophage receptor. Soluble CD163 (sCD163) is an emerging prognostic player in the field of hematopoietic neoplasms. This study aimed to assess the prognostic potential of sCD163 as a serological marker in CLL. The study included 41 CLL patients and 44 apparently normal healthy volunteers as controls. Expression of CD38 and cytoplasmic ZAP 70 in CLL cells was assessed using flow cytometry. Beta 2 microglobulin (B2M), sCD23, and sCD163 serological markers were measured by ELISA. Serum levels of sCD163 were statistically significantly higher in CLL cases compared to controls (p=0.000). sCD163 levels were positively correlated with absolute lymphocyte count, sCD23, and B2M levels (p= 0.027, p=0.01, and p=0.004, respectively). In conclusion, levels of sCD163 in CLL is a promising prognostic tool for evaluating disease progression.

Promoter methylation might shift the balance of Galectin-3 & 12 expression in de novo adult acute myeloid leukemia patients.

Acute myeloid leukemia (AML) was reported as the most common type of leukemia among adults. Galectins constitute a family of galactose-binding proteins reported to play a critical role in many malignancies including AML. Galectin-3 and -12 are members of the mammalian galectin family. To understand the contribution of galectin-3 and -12 promoter methylation to their expression, we performed bisulfite methylation-specific (MSP)-PCR and bisulfite genomic sequencing (BGS) of primary leukemic cells in patients with de novo AML before receiving any therapy. Here, we show a significant loss of LGALS12 gene expression in association with promoter methylation. The lowest degree of expression was found in the methylated (M) group while the highest degree was in the unmethylated (U) group and the partially methylated (P) group expression lies in between. This was not the case with galectin-3 in our cohort unless the CpG sites analyzed were outside the frame of the studied fragment. We were also able to identify four CpG sites (CpG number 1, 5, 7& 8) in the promoter region of galectin-12; these sites must be unmethylated so that expression can be induced. As far as the authors know, these findings were not previously concluded in earlier studies.

Modeling the Effect of Hydrophobicity on the Passive Permeation of Solutes across a Bacterial Model Membrane.

Passive diffusion across biomembranes is an important mechanism of permeation for multiple drugs, including antibiotics. However, this process is frequently neglected while studying drug uptake and, in our view, warrants further investigation. Here, we apply molecular dynamics simulations to investigate the impact of changes in molecular hydrophobicity on the permeability of a series of inhibitors of the quorum sensing of Pseudomonas aeruginosa, previously discovered by us, across a membrane model. Overall, we show that permeation across this membrane model does not correlate with the molecule's hydrophobicity. We demonstrate that using a simple model for permeation, based on the difference between the maximum and minimum of the free energy profile, outperforms the inhomogeneous solubility-diffusion model, yielding a permeability ranking that better agrees with the experimental results, especially for hydrophobic permeants. The calculated differences in permeability could not explain differences in in bacterio activity. Nevertheless, substantial differences in molecular orientation along the permeation pathway correlate with the in bacterio activity, emphasizing the importance of analyzing, at an atomistic level, the permeation pathway of these solutes.

An Outer Membrane Vesicle-Based Permeation Assay (OMPA) for Assessing Bacterial Bioavailability.

When searching for new antibiotics against Gram-negative bacterial infections, a better understanding of the permeability across the cell envelope and tools to discriminate high from low bacterial bioavailability compounds are urgently needed. Inspired by the phospholipid vesicle-based permeation assay (PVPA), which is designed to predict non-facilitated permeation across phospholipid membranes, outer membrane vesicles (OMVs) of Escherichia coli either enriched or deficient of porins are employed to coat filter supports for predicting drug uptake across the complex cell envelope. OMVs and the obtained in vitro model are structurally and functionally characterized using cryo-TEM, SEM, CLSM, SAXS, and light scattering techniques. In vitro permeability, obtained from the membrane model for a set of nine antibiotics, correlates with reported in bacterio accumulation data and allows to discriminate high from low accumulating antibiotics. In contrast, the correlation of the same data set generated by liposome-based comparator membranes is poor. This better correlation of the OMV-derived membranes points to the importance of hydrophilic membrane components, such as lipopolysaccharides and porins, since those features are lacking in liposomal comparator membranes. This approach can offer in the future a high throughput screening tool with high predictive capacity or can help to identify compound- and bacteria-specific passive uptake pathways.

A hydrogel-based in vitro assay for the fast prediction of antibiotic accumulation in Gram-negative bacteria.

The pipeline of antibiotics has been for decades on an alarmingly low level. Considering the steadily emerging antibiotic resistance, novel tools are needed for early and easy identification of effective anti-infective compounds. In Gram-negative bacteria, the uptake of anti-infectives is especially limited. We here present a surprisingly simple in vitro model of the Gram-negative bacterial envelope, based on 20% (w/v) potato starch gel, printed on polycarbonate 96-well filter membranes. Rapid permeability measurements across this polysaccharide hydrogel allowed to correctly predict either high or low accumulation for all 16 tested anti-infectives in living Escherichia coli. Freeze-fracture TEM supports that the macromolecular network structure of the starch hydrogel may represent a useful surrogate of the Gram-negative bacterial envelope. A random forest analysis of in vitro data revealed molecular mass, minimum projection area, and rigidity as the most critical physicochemical parameters for hydrogel permeability, in agreement with reported structural features needed for uptake into Gram-negative bacteria. Correlating our dataset of 27 antibiotics from different structural classes to reported MIC values of nine clinically relevant pathogens allowed to distinguish active from nonactive compounds based on their low in vitro permeability specifically for Gram-negatives. The model may help to identify poorly permeable antimicrobial candidates before testing them on living bacteria.