Spatiotemporal Distribution of Calcium Oxalate Crystals in a Microchannel

The formation of crystals under physicochemical and flow dynamic conditions in constrained dimensions is ubiquitous in nature and of great interest to different disciplines in science. In this report, using a physicochemical approach, we investigated the spatiotemporal precipitation of calcium oxalate (CaOx) crystals, the most common chemical compound found in kidney stones, at the dynamic interface generated by the interdiffusion of oxalate and calcium ions in a microchannel. Spatiotemporal crystal habit distributions were mapped and analyzed using scanning electron microscopy, and their formation was correlated to a numerical model that accounts for supersaturation and gravity. We show that while monohydrated CaOx crystals are the most frequent with random distribution in the channel, the dihydrated CaOx phase crystals are mainly formed at the contact line between oxalate and calcium at the oxalate side, where gradients are large and supersaturation is low. In addition, the size of the crystals correlates well with the supersaturation with increasing monodispersity over time. These results are supported by the numerical model. The simulations also show that nucleation can occur everywhere in the channel; however, with time, nucleation is limited to the upper level of the channel, while crystals on the bottom continue to grow from the reactants

Prevalence of selective IgA deficiency in a sample of Egyptian patients with type 1 diabetes mellitus

Background: Selective Immunoglobulin A deficiency (SIgAD) is known to be one of the most frequent primary immunodeficiency diseases. Several studies worldwide confirm the increased frequency of this disease among type 1 diabetes mellitus (T1DM), yet this has not been studied in Egypt.Objective: This work aimed to define the prevalence of SIgAD among Egyptian patients with T1DM.Patients and Methods: Fifty patients with T1DM were compared to fifty apparently healthy individuals. Serum levels of IgA, IgG, and Immunoglobulin M (IgM) levels were measured by Nephelometry to all participants.Results: The mean age of the diabetic group was 24.5 ± 5.3 years. Thirty out of fifty patients with T1DM (60%) were diagnosed as SIgAD with, female predominance (66.7% of SIgAD). We also found a significant relationship between SIgAD and diabetic ketoacidosis (P-value<0.001). Serum IgA levels were positively correlated to IgG and IgM. Conclusion: The current study displays 60% prevalence of SIgAD among adult Egyptians with T1DM, which is higher than stated in other countries

Preventing Biofilm Formation and Encrustation on Urinary Implants: (Bio)molecular and Physical Research Approaches

Stents and catheters are used to facilitate urine drainage within the urinary system. When such sterile implants are inserted into the urinary tract, ions, macromolecules and bacteria from urine, blood or underlying tissues accumulate on their surface. We presented a brief but comprehensive overview of future research strategies in the prevention of urinary device encrustation with an emphasis on biodegradability, molecular, microbiological and physical research approaches. The large and strongly associated field of stent coatings and tissue engineering is outlined elsewhere in this book. There is still plenty of room for future investigations in the fields of material science, surface science, and biomedical engineering to improve and create the most effective urinary implants. In an era where material science, robotics and artificial intelligence have undergone great progress, futuristic ideas may become a reality. These ideas include the creation of multifunctional programmable intelligent urinary implants (core and surface) capable to adapt to the complex biological and physiological environment through sensing or by algorithms from artificial intelligence included in the implant. Urinary implants are at the crossroads of several scientific disciplines, and progress will only be achieved if scientists and physicians collaborate using basic and applied scientific approaches

Evaluation the Effectiveness of CMC and Klucel-E Modified with TiO2 and ZnO Nanoparticles Used for Consolidation the Damaged Paper Maps

The main goal of this work is to study and evaluate the effectiveness of nano titanium dioxide and nano zinc oxide for enhancing the performances of Carboxymethyl cellulose CMC and Klucel-E used as consolidation materials for historical paper maps. Historical map samples dating back to 1817 & 1952 A.D were treated with CMC and Klucel-E loaded with TiO2 nanoparticles and ZnO nanoparticles. Some of the treated samples were submitted to investigation methods and others were submitted to the artificial thermal aging and then to investigation methods to monitor the changes of consolidation materials after accelerated aging test and to evaluate their effect on mechanical, physical and chemical properties of historical  paper samples under effect of  artificial heat  ageing. Visual assessment, pH measurements, Attenuated Total Reflection infrared spectroscopy (FTIR- ATR) study and mechanical properties determination were undertaken, to see if any significant structural or chemical differences could be detected between “untreated”, “treated” and “treated aged” samples. The results showed that no dramatic changes in functional groups on the paper, as monitored by infrared spectroscopy, occurred in the samples before and after treatment; pH values, however, showed that the tested nanocomposites gave good results in decreasing the acidity of the treated paper. The nanocomposites also enhanced optical and mechanical properties of treated samples

Utility of (2,4-dioxo-1,4-dihydro-2H-quinazolin-3-yl)-acetic acid hydrazide in the synthesis of some heterocyclic nitrogen compounds

An efficient synthesis of (2,4-dioxo-1,4-dihydro-2H-quinazolin-3-yl)-acetic acid hydrazide (3) has been achieved and described. The obtained hydrazide (3) was used in building of some interesting heterocycles such as, triazole, oxadiazole, pyrazole, phthalazine, and indol-2-one rings at position 3. The structures of the obtained compounds were confirmed by IR, 1H NMR, 13C NMR, MS spectral and elemental analysis

THE FLAVONOID CONSTITUNTS OF LEUCAENA LEUCOCEPHALA. GROWING IN EGYPT, AND THEIR BIOLOGICAL ACTIVITY.

Background: Leucaena leucocephala is native to Southern Mexico and Northern Central America, but is now naturalized throughout the tropics. The phyto-chemical data of L. leucocephala revealed the presence of terpenes, flavonoids, coumarins and sterols. Various parts of L. leucocephala have been reported to have medicinal properties. Materials and Methods: Flavonoids were isolated from the aerial parts of L. leucocephala. Antioxidant activity of the extracts and the isolated compounds was evaluated using (DPPH), as well as their cytotoxic activity using a single tumor [Ehrlish ascites carcinoma cells]. Results: The flavonoidal constituents isolated from chloroform, ethyl acetate and n-butanol fractions of the aqueous alcoholic extract of aerial parts of Leucaena leucocephala were identified as Caffeic acid, Isorhamnetin, Chrysoeriol, Isorhamnetin 3-O-galactoside, Kaempferol-3-O-rubinoside, Quercetin-3-O-rhamnoside and Luteolin-7-glucoside. Chemical structures of the isolated compounds were identified by TLC, PC and spectral techniques (UV, 1H -NMR and MS). The ethyl acetate fraction and the isolated flavonoidal compounds showed high antioxidant activity compared to Trolox (standard antioxidant compound). The different fractions and isolated compounds of Leucaena leucocephala exhibited no cytotoxic activity against Ehrlich- ascitis carcinoma cell line at the tested concentrations. Conclusion: This is the first record of the flavonoids in the aerial parts of Leucaena leucocephala (L.) except Quercetin-3-O-rhamnoside

Sprouting droplets driven by physical effects alone

International audienc

Recent insights in magnetic hyperthermia: From the “hot-spot” effect for local delivery to combined magneto-photo-thermia using magneto-plasmonic hybrids

International audienceMagnetic hyperthermia which exploits the heat generated by magnetic nanoparticles (MNPs) when exposed to an alternative magnetic field (AMF) is now in clinical trials for the treatment of cancers. However, this thermal therapy requires a high amount of MNPs in the tumor to be efficient. On the contrary the hot spot local effect refers to the use of specific temperature profile at the vicinity of nanoparticles for heating with minor to no long-range effect. This magneto-thermal effect can be exploited as a relevant external stimulus to temporally and spatially trigger drug release.In this review, we focus on recent advances in magnetic hyperthermia. Indirect experimental proofs of the local temperature increase are first discussed leading to a good estimation of the temperature at the surface (from 0.5 to 6 nm) of superparamagnetic NPs. Then we highlight recent studies illustrating the hot-spot effect for drug- release. Finally, we present another recent strategy to enhance the efficacity of thermal treatment by combining photothermal therapy with magnetic hyperthermia mediated by magneto-plasmonic nanoplatforms

Novel strategies to prevent and overcome relapse after allogeneic hematopoietic cell transplantation in acute lymphoblastic leukemia

The outcome of B-cell acute lymphoblastic leukemia (B-ALL) has improved over time with the incorporation of multi-agent chemotherapy in the treatment landscape as well as the recent approval of immunotherapeutic agents allowing a larger proportion of patients to undergo allogeneic hematopoietic cell transplantation (allo-HCT) which is still considered a potential curative approach. However, relapse post-transplant is still occurring and constitutes a common cause of treatment failure in B-ALL. The present review aims to discuss the novel strategies and therapies used to prevent and overcome relapse post allo-HCT in patients with ALL, focusing on the role of tyrosine kinase inhibitors in Philadelphia chromosome positive B-ALL, the role of innovative agents such as blinatumomab and inotuzumab ozogamicin, and finally the role of cellular therapy