Copper nanoparticles biosynthesis by Stevia rebaudiana extract: biocompatibility and antimicrobial application.

The growth of material science and technology places a high importance on the creation of better processes for the synthesis of copper nanoparticles. So that, an easy, ecological, and benign process for producing copper nanoparticles (CuNPs) has been developed using candy leaf (Stevia rebaudiana) leaves aqueous extract for the first time. UV-visible spectroscopy, dynamic light scattering (DLS), X-ray diffraction (XRD), high-resolution transmission electron microscope (HR-TEM), Fourier transmission infrared (FTIR), and zeta potential were applied to demonstrate strong characterization for the biosynthesized stevia-CuNPs. The UV-visible absorbance at 575 nm of surface plasmon resonance (SPR) was 1.2. The particle size mean diameter was recorded as 362.3 nm with - 10.8 mV zeta potential. The HR-TEM scanning revealed 51.46-53.17 nm and spherical-shaped stevia-CuNPs surrounded by coat-shell proteins. The cytotoxicity and cytocompatibility activity assay revealed that stevia-CuNPs was safe in lower concentrations and had a significant cell viability reduction in higher concentrations. The produced stevia-CuNPs were applied as antimicrobial agents against eight pathogenic bacteria and five fungi strains. The inhibitory action of the stevia-CuNPs was more pronounced in bacteria than in fungi, and they likewise demonstrated further inhibition zones in Staphylococcus aureus (50.0 mm) than in Aspergillus flavus (55.0 mm). With inhibition zone sizes of 50.0 mm and 47.0 mm and 50 µg/ml minimum inhibitory concentration, S. aureus and A. flavus were the most inhibited pathogens. The minimum lethal effect (MLC) estimate for S. aureus was 50 µg/ml, whereas 75 µg/ml for A. flavus. The stevia-CuNPs mode of action was characterized as bactericidal/fungicidal as the ratio of MIC to MLC was estimated to be equal to or less than 2. After all, stevia-CuNPs could be used as an alternative to commercial antibiotics to solve the problem of multidrug-resistant (MDR) microorganisms.

Optimizing the synthesis of yeast Beta-glucan via response surface methodology for nanotechnology application.

BACKGROUND: The production of biopolymers from waste resources is a growing trend, especially in high-population countries like Egypt. Beta-glucan (ß-glucan) belongs to natural polysaccharides that are derived from plant and microbial origins. In this study, following increasing demands for ß-glucan owing to its bioactive properties, a statistical model to enhance microbial ß-glucan production was evaluated for its usefulness to the food and pharmaceutical industries. In addition, a trial to convert ß-glucan polymer to nanostructure form was done to increase its bioactivity. RESULTS: Ingredients of low-cost media based on agro-industrial wastes were described using Plackett-Burman and central composite design of response surface methodology for optimizing yeast ß-glucan. Minerals and vitamin concentrations significantly influenced ß-glucan yield for Kluyveromyces lactis and nitrogen and phosphate sources for Meyerozyma guilliermondii. The maximum predicted yields of ß-glucan recovered from K. lactis and M. guilliermondii after optimizing the medium ingredients were 407 and 1188 mg/100 ml; respectively. For the first time, yeast ß-glucan nanoparticles (ßGN) were synthesized from the ß-glucan polymer using N-dimethylformamide as a stabilizer and characterized using UV-vis spectroscopy, transmission electron microscope (TEM), dynamic light scattering (DLS) and Fourier transform infrared spectroscopy (FT-IR). The average size of ßGN was about 300 nm as determined by DLS. The quantitative variation of functional groups between ß-glucan polymer and ßGN was evaluated by FT-IR for explaining the difference in their biological activity against Normal Homo sapiens-Hela contaminant and Hepatic cancer cell lines. CONCLUSIONS: Enriching the low-cost media based on agro-industrial wastes with nutritional ingredients improves the yield of yeast ß-glucan. The present study succeeds to form ß-glucan nanoparticles by a simple method.

The value of modified Ross score in the evaluation of children with severe lower respiratory tract infection admitted to the pediatric intensive care unit.

Heart failure (HF) represents an important cause of morbidity and mortality in children. It is mostly caused by congenital heart disease (CHD) and cardiomyopathy. The Ross HF classification was developed to assess severity in infants and has subsequently been modified to apply to all pediatric ages. The modified Ross classification for children provides a numeric score comparable with the New York Heart Association (NYHA) HF classification for adults. The aim of this work is to investigate the role of modified Ross score in the evaluation of children with severe lower respiratory tract infection admitted to the pediatric intensive care unit (PICU). One hundred and sixty-four children with severe LRTI admitted to the PICU were enrolled in this prospective cohort study, which was carried out at Assiut University Children Hospital, from the start of July 2021 up to the end of December 2021. Sixty patients (36.6%) of studied cases with severe LRTI admitted to PICU had HF. Out of these, 37 (61.7%) had mild HF; 17 (28.3%) had moderate HF, while six cases (10%) had severe HF according to the modified Ross score. The value of modified Ross score was significantly higher in children with heart failure with sensitivity and specificity 100% with cutoff value of 2. Admission to NICU, history of previous ventilation, and prematurity were higher in patients who developed HF. Patients with pulmonary hypertension (PH) and those with raised neutrophil lymphocyte ratio were significantly higher in the group of patients with moderate and severe degree of HF.   Conclusion: Modified Ross score is a simple clinical score which may help in assessing and predicting children with severe LRTI. What is Known: • Hear failure is common complication to lower respiratory tract infection. • Modified Ross score was used to predict and classify heart failure in adult with lower respiratory infection. What is New: • Modified Ross score found to be of value in prediction of heart failure in children with lower respiratory tract infection.

Cellulose Nanofibers/Pectin/Pomegranate Extract Nanocomposite as Antibacterial and Antioxidant Films and Coating for Paper.

Bio-based polymer composites find increasing research and industrial interest in different areas of our life. In this study, cellulose nanofibers (CNFs) isolated from sugar beet pulp and nanoemulsion prepared from sugar beet pectin and pomegranate extract (PGE) were used for making films and used as coating with antioxidant and antimicrobial activities for paper. For Pectin/PGE nanoemulsion preparation, different ratios of PGE were mixed with pectin using ultrasonic treatment; the antibacterial properties were evaluated to choose the formula with the adequate antibacterial activity. The antioxidant activity of the nanoemulsion with the highest antimicrobial activity was also evaluated. The nanoemulsion with the optimum antibacterial activity was mixed with different ratios of CNFs. Mechanical, greaseproof, antioxidant activity, and antibacterial properties of the CNFs/Pectin/PGE films were evaluated. Finally, the CNFs/Pectin/PGE formulation with the highest antibacterial activity was tested as a coating material for paper. Mechanical, greaseproof, and air porosity properties, as well as water vapor permeability and migration of the coated layer from paper sheets in different media were evaluated. The results showed promising applicability of the CNFs/Pectin/PGE as films and coating material with antibacterial and antioxidant activities, as well as good stability for packaging aqueous, fatty, and acidic food products.

New pectin derivatives with antimicrobial and emulsification properties via complexation with metal-terpyridines.

Pectin is widely used in food and pharmaceutical industries. However, due to its polysaccharide nature it lacks antimicrobial activity. In the current work, new pectin derivatives with interesting optical and antimicrobial properties were prepared via supramolecular chemistry utilizing Fe- or Cu-terpyridine (Tpy-Fe and Tpy-Cu) motifs. To proof derivatization of pectin, ultraviolet-visible spectroscopy (UV-Vis) and Fourier Transform infrared (FTIR) were used. In addition, the prepared pectin derivatives retained the known emulsification activity of the non-modified sugar beet pectin as seen from the particle size analysis of oil-in-water emulsions. The prepared derivatives showed antibacterial activity toward selected Gram-positive and Gram-negative bacteria. In addition, cytotoxicity test showed that the Tpy-Fe-pectin derivative was non-toxic to cells of human hepatocarcinoma, breast adenocarcinoma MCF7, and colorectal carcinoma cells at concentrations up to 100 µg/ml, while Tpy-Cu-pectin had moderate toxicity toward the aforementioned cells at the same concentration levels. The prepared derivatives could have potential applications in emulsions with antibacterial activity.

Process analysis of pluripotent stem cell differentiation to megakaryocytes to make platelets applying European GMP.

Quality, traceability and reproducibility are crucial factors in the reliable manufacture of cellular therapeutics, as part of the overall framework of Good Manufacturing Practice (GMP). As more and more cellular therapeutics progress towards the clinic and research protocols are adapted to comply with GMP standards, guidelines for safe and efficient adaptation have become increasingly relevant. In this paper, we describe the process analysis of megakaryocyte manufacture from induced pluripotent stem cells with a view to manufacturing in vitro platelets to European GMP for transfusion. This process analysis has allowed us an overview of the entire manufacturing process, enabling us to pinpoint the cause and severity of critical risks. Risk mitigations were then proposed for each risk, designed to be GMP compliant. These mitigations will be key in advancing this iPS-derived therapy towards the clinic and have broad applicability to other iPS-derived cellular therapeutics, many of which are currently advancing towards GMP-compliance. Taking these factors into account during protocol design could potentially save time and money, expediting the advent of safe, novel therapeutics from stem cells.

Biosynthesis and Characterization of Extracellular Silver Nanoparticles from Streptomyces aizuneusis: Antimicrobial, Anti Larval, and Anticancer Activities.

The ability of microorganisms to reduce inorganic metals has launched an exciting eco-friendly approach towards developing green nanotechnology. Thus, the synthesis of metal nanoparticles through a biological approach is an important aspect of current nanotechnology. In this study, Streptomyces aizuneusis ATCC 14921 gave the small particle of silver nanoparticles (AgNPs) a size of 38.45 nm, with 1.342 optical density. AgNPs produced by Streptomyces aizuneusis were characterized by means of UV-VIS spectroscopy and transmission electron microscopy (TEM). The UV-Vis spectrum of the aqueous solution containing silver ion showed a peak between 410 to 430. Moreover, the majority of nanoparticles were found to be a spherical shape with variables between 11 to 42 nm, as seen under TEM. The purity of extracted AgNPs was investigated by energy dispersive X-ray analysis (EDXA), and the identification of the possible biomolecules responsible for the reduction of Ag+ ions by the cell filtrate was carried out by Fourier Transform Infrared spectrum (FTIR). High antimicrobial activities were observed by AgNPs at a low concentration of 0.01 ppm, however, no deleterious effect of AgNPs was observed on the development and occurrence of Drosophila melanogaster phenotype. The highest reduction in the viability of the human lung carcinoma and normal cells was attained at 0.2 AgNPs ppm.

Water purification ultrafiltration membranes using nanofibers from unbleached and bleached rice straw.

There has been an increasing interest in recent years in isolating cellulose nanofibers from unbleached cellulose pulps for economic, environmental, and functional reasons. In the current work, cellulose nanofibers isolated from high-lignin unbleached neutral sulfite pulp were compared to those isolated from bleached rice straw pulp in making thin-film ultrafiltration membranes by vacuum filtration on hardened filter paper. The prepared membranes were characterized in terms of their microscopic structure, hydrophilicity, pure water flux, protein fouling, and ability to remove lime nanoparticles and purify papermaking wastewater effluent. Using cellulose nanofibers isolated from unbleached pulp facilitated the formation of a thin-film membrane (with a shorter filtration time for thin-film formation) and resulted in higher water flux than that obtained using nanofibers isolated from bleached fibers, without sacrificing its ability to remove the different pollutants.

Vector Copy Distribution at a Single-Cell Level Enhances Analytical Characterization of Gene-Modified Cell Therapies.

The ability to deliver transgenes into the human genome using viral vectors is a major enabler of the gene-modified cell therapy field. However, the control of viral transduction is difficult and can lead to product heterogeneity, impacting efficacy and safety, as well as increasing the risk of batch failure during manufacturing. To address this, we generated a novel analytical method to measure vector copy distribution at the single-cell level in a gene-modified, lentiviral-based immunotherapy model. As the limited amount of genomic DNA in a single cell hinders reliable quantification, we implemented a preamplification strategy on selected lentiviral and human gene targets in isolated live single cells, followed by quantification of amplified material by droplet digital PCR. Using a bespoke probability framework based on Bayesian statistics, we show that we can estimate vector copy number (VCN) integers with maximum likelihood scores. Notably, single-cell data are consistent with population analysis and also provide an overall measurement of transduction efficiency by discriminating transduced (VCN ≥ 1) from nontransduced (VCN = 0) cells. The ability to characterize cell-to-cell variability provides a powerful high-resolution approach for product characterization, which could ultimately allow improved control over product quality and safety.

A modified CD34+ hematopoietic stem and progenitor cell isolation strategy from cryopreserved human umbilical cord blood.

BACKGROUND: Umbilical cord blood (UCB) is a source of hematopoietic stem cells for transplantation, offering an alternative for patients unable to find a matched adult donor. UCB is also a versatile source of hematopoietic stem and progenitor cells (hCD34 + HSPCs) for research into hematologic diseases, in vitro expansion, ex vivo gene therapy, and adoptive immunotherapy. For these studies, there is a need to isolate hCD34 + HSPCs from cryopreserved units, and protocols developed for isolation from fresh cord blood are unsuitable. STUDY DESIGN: This study describes a modified method for isolating hCD34 + HSPCs from cryopreserved UCB. It uses the Plasmatherm system for thawing, followed by CD34 microbead magnetic-activated cell sorting isolation with a cell separation kit (Whole Blood Columns, Miltenyi Biotec). hCD34 + HSPC phenotypes and functionality were assessed in vitro and hematologic reconstitution determined in vivo in immunodeficient mice. RESULTS: Total nucleated cell recovery after thawing and washing was 44.7 ± 11.7%. Recovery of hCD34 + HSPCs after application of thawed cells to Whole Blood Columns was 77.5 ± 22.6%. When assessed in two independent laboratories, the hCD34+ cell purities were 71.7 ± 10.7% and 87.8 ± 2.4%. Transplantation of the enriched hCD34 + HSPCs into NSG mice revealed the presence of repopulating hematopoietic stem cells (estimated frequency of 0.07%) and multilineage engraftment. CONCLUSION: This provides a simplified protocol for isolating high-purity human CD34 + HSPCs from banked UCB adaptable to current Good Manufacturing Practice. This protocol reduces the number of steps and associated risks and thus total production costs. Importantly, the isolated CD34 + HSPCs possess in vivo repopulating activity in immunodeficient mice, making them a suitable starting population for ex vivo culture and gene editing.

Bacterial cellulose/phytochemical's extracts biocomposites for potential active wound dressings.

The present study describes the impregnation of coffee extract (CE) into bacterial cellulose synthesized from kombucha tea fungus (KBC) of different cellulose content, incubated for different incubation periods (2, 4, and 10 days), to prepare biocomposites having the potential for wound healing applications. Total polyphenols in hydroalcoholic extracts from ground roasted coffee and its release from the prepared biocomposites were determined as gallic acid equivalent. The polyphenols content was found to be 13.66 mg/g and the minimum inhibitory concentration (MIC) of the CE was determined using colony-forming unit (CFU) method against Gram-negative bacteria Escherichia coli and Gram-positive bacteria Staphylococcus aureus where the growth inhibition was 86 and 97% respectively. Biocomposites (KBC/CE) with the lowest cellulose and CE content showed the highest wet tensile stress (3.35 MPa), absorption of pseudo extracellular fluid (154.32% ± 4.84), and water vapor transmission rate (3184.94 ± 198.07 g/m2/day), whereas it showed the lowest polyphenols' release (51.85% ± 2.94)when immersed in PBS buffer of pH 7.4. The impregnation of CE into KBC provided biocomposites that can enlarge the range of BC in the biomedical application.

Effect of Unbleached Rice Straw Cellulose Nanofibers on the Properties of Polysulfone Membranes.

In addition to their lower cost and more environmentally friendly nature, cellulose nanofibers isolated from unbleached pulps offer different surface properties and functionality than those isolated from bleached pulps. At the same time, nanofibers isolated from unbleached pulps keep interesting properties such as hydrophilicity and mechanical strength, close to those isolated from bleached pulps. In the current work, rice straw nanofibers (RSNF) isolated from unbleached neutral sulfite pulp (lignin content 14%) were used with polysulfone (PSF) polymer to make membrane via phase inversion. The effect of RSNF on microstructure, porosity, hydrophilicity, mechanical properties, water flux, and fouling of PSF membranes was studied. In addition, the prepared membranes were tested to remove lime nanoparticles, an example of medium-size nanoparticles. The results showed that using RSNF at loadings from 0.5 to 2 wt.% can significantly increase hydrophilicity, porosity, water flux, and antifouling properties of PSF. RSNF also brought about an increase in rejection of lime nanoparticles (up to 98% rejection) from their aqueous suspension, and at the same time, with increasing flux across the membranes. Tensile strength of the membranes improved by ~29% with addition of RSNF and the maximum improvement was obtained on using 0.5% of RSNF, while Young's modulus improved by ~40% at the same RSNF loading. As compared to previous published results on using cellulose nanofibers isolated from bleached pulps, the obtained results in the current work showed potential application of nanofibers isolated from unbleached pulps for improving important properties of PSF membranes, such as hydrophilicity, water flux, rejection, and antifouling properties.

Nanocomposite Film Based on Cellulose Acetate and Lignin-Rich Rice Straw Nanofibers.

Nanofibers isolated from unbleached neutral sulfite rice straw pulp were used to prepare transparent films without the need to modify the isolated rice straw nanofibers (RSNF). RSNF with loading from 1.25 to 10 wt.% were mixed with cellulose acetate (CA) solution in acetone and films were formed by casting. The films were characterized regarding their transparency and light transmittance, microstructure, mechanical properties, crystallinity, water contact angle, porosity, water vapor permeability, and thermal properties. The results showed good dispersion of RSNF in CA matrix and films with good transparency and homogeneity could be prepared at RSNF loadings of less than 5%. As shown from contact angle and atomic force microscopy (AFM) measurements, the RSNF resulted in increased hydrophilic nature and roughness of the films. No significant improvement in tensile strength and Young's modulus was recorded as a result of adding RSNF to CA. Addition of the RSNF did not significantly affect the porosity, crystallinity and melting temperature of CA, but slightly increased its glass transition temperature.

Prevalence of childhood and adolescence epilepsy in Upper Egypt (desert areas).

BACKGROUND: A high prevalence of epilepsy in children is frequently found in developing countries. OBJECTIVE: This study aimed to determine the prevalence and clinical pattern of childhood and adolescence epilepsy in Upper Egypt. METHODS: This is a door-to-door study conducted on all inhabitants < 18 years in Al Kharga district and Al Qusier city (36,195 subjects). The study was conducted through two stages; every stage consisted of two phases (screening and diagnostic). RESULTS: Lifetime prevalence of childhood and adolescence epilepsy (children < 18 years) in Upper Egypt was 9.7/1000, with higher prevalence among children < 12 years (10.8/1000) than adolescents (7.2/1000). The age-specific prevalence was highest in early childhood (12.01/1000) and least at adolescence (7.2/1000). More than half of the patients (59.4%) had idiopathic epilepsy. The most frequent etiology for structural/metabolic epilepsy was perinatal complications, particularly in infancy, followed by central nervous system (CNS) infections, in childhood, and post-traumatic epilepsy in adolescence. Partial seizures were more frequent in infancy, while generalized seizures were more frequent in late childhood and adolescence. Generalized tonic-clonic seizures (GTCS) were the most frequent type of seizures. CONCLUSION: Prevalence of childhood and adolescence epilepsy in Upper Egypt was not so much different from other developing countries. Idiopathic epilepsy was more prevalent than structural/metabolic cases. Perinatal complications, CNS infections, and head injury were the most frequent etiologies, and generalized tonic-clonic seizures were the most frequent seizure type.

Application of Raman Spectroscopy and Univariate Modelling As a Process Analytical Technology for Cell Therapy Bioprocessing.

Cell therapies offer unquestionable promises for the treatment, and in some cases even the cure, of complex diseases. As we start to see more of these therapies gaining market authorization, attention is turning to the bioprocesses used for their manufacture, in particular the challenge of gaining higher levels of process control to help regulate cell behavior, manage process variability, and deliver product of a consistent quality. Many processes already incorporate the measurement of key markers such as nutrient consumption, metabolite production, and cell concentration, but these are often performed off-line and only at set time points in the process. Having the ability to monitor these markers in real-time using in-line sensors would offer significant advantages, allowing faster decision-making and a finer level of process control. In this study, we use Raman spectroscopy as an in-line optical sensor for bioprocess monitoring of an autologous T-cell immunotherapy model produced in a stirred tank bioreactor system. Using reference datasets generated on a standard bioanalyzer, we develop chemometric models from the Raman spectra for glucose, glutamine, lactate, and ammonia. These chemometric models can accurately monitor donor-specific increases in nutrient consumption and metabolite production as the primary T-cell transition from a recovery phase and begin proliferating. Using a univariate modeling approach, we then show how changes in peak intensity within the Raman spectra can be correlated with cell concentration and viability. These models, which act as surrogate markers, can be used to monitor cell behavior including cell proliferation rates, proliferative capacity, and transition of the cells to a quiescent phenotype. Finally, using the univariate models, we also demonstrate how Raman spectroscopy can be applied for real-time monitoring. The ability to measure these key parameters using an in-line Raman optical sensor makes it possible to have immediate feedback on process performance. This could help significantly improve cell therapy bioprocessing by allowing proactive decision-making based on real-time process data. Going forward, these types of in-line sensors also open up opportunities to improve bioprocesses further through concepts such as adaptive manufacturing.

Influence of TEMPO-oxidized NFC on the mechanical, barrier properties and nisin release of hydroxypropyl methylcellulose bioactive films.

Bioactive films from hydroxypropyl methylcellulose (HPMC), nisin (N), and different percentage (5% to 75%) of TEMPO-oxidized nanofibrillated cellulose (NFC) isolated from rice straw pulp were prepared by solution casting technique and their properties were studied. Scanning electron microscope images (SEM) of films showed homogeneous surface with absence of nanofibers agglomeration. The mechanical and barrier properties were evaluated by measuring their tensile strength, tensile modulus, strain at maximum load, dynamic mechanical thermal properties (DMTA), and water vapor permeability (WVP). In all films, there was an improvement in the mechanical, thermomechanical, and moisture barrier properties as a result of presence of NFC. The molecular structure of the films was studied by Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction patterns (XRD). Presence of NFC in HPMC films affected crystallinity of the later. The prepared HPMC/N, NFC/N, and HPMC/N/NFC films exhibited significant antimicrobial activities against Gram-positive bacteria Staphylococcus aureus with noticeable controlled release of nisin in case of films containing HPMC/NFC.

Chitosan nanoparticles/cellulose nanocrystals nanocomposites as a carrier system for the controlled release of repaglinide.

The aim of the present work was to study the use of cellulose nanocrystals (CNC) and chitosan nanoparticles (CHNP) for developing controlled-release drug delivery system of the anti-hyperglycemic drug Repaglinide (RPG). CNC was isolated from palm fruit stalks by sulfuric acid hydrolysis; the dimensions of the isolated nanocrystals were 86-237 nm in length and 5-7 nm in width. Simple and economic method was used for the fabrication of controlled release drug delivery system from CNC and CHNP loaded with RPG drug via ionic gelation of chitosan in the presence of CNC and RPG. The prepared systems showed high drug encapsulation efficiency of about ~98%. Chemical modification of CNC by oxidation to introduce carboxylic groups on their surface (OXCNC) was also carried out for further controlling of RPG release. Particles size analysis showed that the average size of CHNP was about 197 nm while CHNP/CNC/RPG or CHNP/OXCNC/RPG nanoparticles showed average size of 215-310 nm. Compatibility studies by Fourier transform infrared (FTIR) spectroscopy showed no chemical reaction between RPG and the system's components used. By studying the drug release kinetic, all the prepared RPG formulations followed Higuchi model, indicating that the drug released by diffusion through the nanoparticles polymeric matrix.

Use of Bacterial Cellulose and Crosslinked Cellulose Nanofibers Membranes for Removal of Oil from Oil-in-Water Emulsions.

Abstract: Never-dried bacterial cellulose (BC) and crosslinked cellulose nanofibers (CNF) were used for the removal of oil from stabilized and non-stabilized oil-in-water emulsions with droplet sizes less than 1 µm. The CNF membranes were exchanged with isopropyl alcohol before drying. The microscopic structure of the prepared membranes was evaluated using scanning electron microscopy (SEM); the water flux and the rejection of oil were evaluated using a dead-end filtration cell. BC harvested after different incubation time periods (2 to 10 days) did not show a change in the width of the nanofibers, but only the thickness of the membranes was increased. Pure water flux was not affected as a result of increasing thicknesses of BC membranes harvested after 4⁻10 days while BC harvested after two days had significantly higher water flux than the others. BC showed a higher flux and efficiency in removing oil from oil emulsions than CNF membranes. Removal of oil by the different membranes from the non-stabilized oil emulsion was more efficient than from the stabilized one.

Membranes Based on Cellulose Nanofibers and Activated Carbon for Removal of Escherichia coli Bacteria from Water.

Cellulosic nanomaterials are potential candidates in different areas, especially in water treatment. In the current work, palm fruit stalks cellulose nanofibers (CNF), TEMPO-oxidized CNF (OCNF), and activated carbon (AC) were used to make thin film membranes for removal of E. coli bacteria from water. Two types of layered membranes were produced: a single layer setup of crosslinked CNF and a two-layer setup of AC/OCNF (bottom) and crosslinked CNF (up) on hardened filter paper. The prepared membranes were evaluated regarding their microstructure and layers thickness using scanning electron microscopy (SEM). Water flux and rejection of E. coli bacteria was tested using dead end stirred cells at 1 MPa pressure. Thickness of the cosslinked CNF layer in both types of membranes was about 0.75 micron. The results showed that exchanging water by isopropyl alcohol before drying increased porosity of membranes, and thus resulted in increasing pure water flux and flux of bacteria suspension. The two-layer AC/OCNF/CNF membrane had much higher water flux than the single layer CNF due to higher porosity seen on the surface of the former. Both types of membranes showed high capability of removing E. coli bacteria (rejection ~96⁻99%) with slightly higher efficiency for the AC/OCNF/CNF membrane than CNF membrane. AC/OCNF/CNF membrane also showed resistance against growth of E. coli and S. aureus bacteria on the upper CNF surface while the single layer CNF membrane did not show resistance against growth of the aforementioned bacteria.

Epidemiology and clinical presentation of stroke in Upper Egypt (desert area).

BACKGROUND: Stroke is a common cause of morbidity and mortality worldwide. Four out of five strokes occur in the low- and middle-income countries. This study aims to find lifetime prevalence of stroke in Upper Egypt and to identify clinical presentations and possible risk factors of stroke in this population. METHODS: This is a door-to-door (every door) study conducted on all inhabitants in Al Kharga district (representative of western desert) and Al Quseir city (representative of eastern desert). The study was conducted in two stages, and every stage consisted of three phases (screening, diagnostic, and investigatory). RESULTS: The total lifetime prevalence of stroke was 8.5/1,000 in the population aged 20 years and more. It increased with advancing age and was higher among males than females among all age groups except in the childbearing period (20 years to <40 years of age). Lifetime prevalence of ischemic stroke (7.2/1,000) was higher than hemorrhagic stroke (1.1/1,000). Hemiparesis and hemiplegia were the commonest presentation of stroke. Headache, vomiting, and vertigo were found to be significantly more common accompaniments of hemorrhagic stroke. The most common risk factor was hypertension, followed by hyperlipidemia and diabetes mellitus. CONCLUSION: The total lifetime prevalence of stroke in the population aged 20 years and more in Upper Egypt (desert area) lies within the range that is recorded in developing countries. Clinical presentation and risk factors are similar to those recorded from developing and developed countries.