Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 20
Filter
1.
Gels ; 9(10)2023 Sep 25.
Article in English | MEDLINE | ID: mdl-37888354

ABSTRACT

Current research is moving towards iron and ammonia elimination from groundwater. Here, we are using a poly acrylic-poly acrylamide hydrogel that is grafted with 3-chloroaniline. This copolymer was synthesized by addition polymerization technique. The effects of agitation time, dosage and adsorbent temperature on the removal process sensitivity were investigated. The copolymer was described experientially and theoretically. Isothermal kinetic adsorption models are discussed. This hydrogel could be regenerated efficiently (98.3% removal of iron and 100% removal of ammonia). The density functional theory (DFT) method, using B3LYP/6-311G(d,p), and the LANL2DZ level of the theory were managed to investigate the stationary states of the grafted copolymer and the complexation energy of the hydrogel with the studied cations. DFT has been used to investigate the Natural Bond Orbital (NBO) properties to locate the most negative centers on the hydrogel. The calculated complexation energy showed hydrogel selectivity with regard to the studied cations.

2.
Sci Rep ; 13(1): 12756, 2023 Aug 07.
Article in English | MEDLINE | ID: mdl-37550378

ABSTRACT

The building construction materials are responsible for a large amount of energy and natural resource consumption. In light of the current challenges of resource scarcity and global climate change, the circular economy (CE) is a promising strategy to mitigate pressure on the environment, improve supplying of raw materials, and increase new market and employment opportunities. Developing eco-friendly thermal insulation materials based on agro-waste is a new waste management trend to achieve the sustainability of the resource and energy consumption in the construction sectors. In this work, banana-polystyrene composites were prepared by mixing the banana peels powder (BP) with polystyrene (PS) in different weight ratios (90:10, 80:20, 70:30, and 60:40). The physical and thermal properties such as thermal conductivity, electrical conductivity, Fourier Transform Infrared (FTIR), crystallographic structures of the fibers, X-Ray Diffraction (XRD), Thermogravimetric Analysis (TGA), and Differential Scanning Calorimetry (DSC) were carried out on BP and BP-PS1 that were prepared with ten wt.% and 20 wt.% of polystyrene powder (BP-PS2). The bio-composites results showed low thermal conductivity ranging from 0.028 to 0.030 W/m.K. The BP-PS2 exhibited a lower thermal conductivity of 0.027 W/m.K, while the pure peel powder demonstrated notable thermal stability, indicated by a total weight loss of 66.4% and a high crystallinity value of 56.1%. Furthermore, the thermal analysis (TGA) and X-Ray Diffraction (XRD) demonstrated that the pure banana peel has the highest thermal stability and crystallinity. These findings indicate that using banana peel-polystyrene composites represents an innovative solution for thermal insulation in buildings as an alternative to conventional materials to reduce energy and resource consumption.

3.
Int J Biol Macromol ; 242(Pt 1): 124768, 2023 Jul 01.
Article in English | MEDLINE | ID: mdl-37169054

ABSTRACT

The highly poisonous, non-biodegradable heavy metals present serious concern in wastewater environmental sustainability and human health. Using adsorption is an effective technology for the treatment of this kind of water. Therefore, developing efficient and cost-effective adsorbents considers a significant and an emerging topic in the field the water purification. Chitosan grafted polyacrylonitrile (Cs-g-PAN) was facially fabricated via graft polymerization using ammonium persulfate (APS) as the initiator. The simple ultrasonic technique was used for doping ZnO nanoparticles into the Cs-g-PAN matrix to prepare chitosan-grafted polyacrylonitrile/ZnO (Cs-g-PAN/ZnO). For comparative study, pure ZnO and nanocomposite of PAN doped with ZnO (PAN/ZnO) were also prepared. XRD, FTIR, SEM, TEM, BET, EDS, and TGA measurements were conducted to confirm the morphological and structural properties of the prepared materials. Cs-g-PAN/ZnO possesses a specific surface area of 20.23 m2/g with a pore size of 31.58 nm and pore volume of 0.16 cm3 g-1. The adsorption behavior toward Fe(II) as a pollutant for groundwater was studied for the synthesized materials. The effect of pH (4-8), contact time (5-60 min), adsorbent dose (0.01-0.3 g), and different temperature degrees (278, 288, 298, 308, and 318 K) on the removal of iron (II) has been conducted. The removal efficiency was achieved 100 % under the optimum condition, at pH = 7, contact time 30 min, adsorbate concentration 0.93 mg/L, and adsorbent dosage 0.05 g/L at room temperature. Langmuir and Freundlich's isothermal and kinetic studies have been analyzed to determine the adsorption mechanism of Fe(II) ions on the synthesized nanomaterials. The adsorption process of Fe(II) over the surface of prepared catalysts proceeded via the Langmuir model and pseudo-second-order reaction kinetics with R2 > 0.99. Suggesting the formation of Fe(II) monolayer over the adsorbent surface and the rate-limiting step is probably controlled by chemisorption through sharing the electrons between Fe+2 and the prepared catalyst.


Subject(s)
Chitosan , Groundwater , Nanocomposites , Water Pollutants, Chemical , Water Purification , Zinc Oxide , Humans , Chitosan/chemistry , Iron , Zinc Oxide/chemistry , Kinetics , Nanocomposites/chemistry , Ferrous Compounds , Adsorption , Water Pollutants, Chemical/chemistry , Hydrogen-Ion Concentration
4.
Plast Surg (Oakv) ; 31(2): 192-205, 2023 May.
Article in English | MEDLINE | ID: mdl-37188139

ABSTRACT

Background: Migraine surgery at 1 of 6 identified "trigger sites" of a target cranial sensory nerve has rapidly grown in popularity since 2000. This study summarizes the effect of migraine surgery on headache severity, headache frequency, and the migraine headache index score which is derived by multiplying migraine severity, frequency, and duration. Materials and Methods: This is a PRISMA-compliant systematic review of 5 databases searched from inception through May 2020 and is registered under the PROSPERO ID: CRD42020197085. Clinical trials treating headaches with surgery were included. Risk of bias was assessed in randomized controlled trials. Meta-analyses were performed on outcomes using a random effects model to determine the pooled mean change from baseline and when possible, to compare treatment to control. Results: 18 studies met criteria including 6 randomized controlled trials, 1 controlled clinical trial, and 11 uncontrolled clinical trials treated 1143 patients with pathologies including migraine, occipital migraine, frontal migraine, occipital nerve triggered headache, frontal headache, occipital neuralgia, and cervicogenic headache. Migraine surgery reduced headache frequency at 1 year postoperative by 13.0 days per month as compared to baseline (I2 = 0%), reduced headache severity at 8 weeks to 5 years postoperative by 4.16 points on a 0 to 10 scale as compared to baseline (I2 = 53%), and reduced migraine headache index at 1 to 5 years postoperative by 83.1 points as compared to baseline (I2 = 2%). These meta-analyses are limited by a small number of studies that could be analyzed, including studies with high risk of bias. Conclusion: Migraine surgery provided a clinically and statistically significant reduction in headache frequency, severity, and migraine headache index scores. Additional studies, including randomized controlled trials with low risk-of-bias should be performed to improve the precision of the outcome improvements.


Historique: Le traitement de la migraine à l'une des six « zones gâchettes ¼ établies d'un nerf crânien sensoriel cible ont rapidement gagné en popularité depuis 2000. La présente étude résume l'effet du traitement chirurgical de la migraine sur la gravité et la fréquence des céphalées et sur le score de migraine obtenu par la multiplication de la gravité, de la fréquence et de la durée des migraines. Matériel et méthodologie: La présente analyse systématique de cinq bases de données fouillées depuis leur création jusqu'à mai 2020 respecte la liste PRISMA et est enregistrée sous le numéro d'identification CRD42020197085 de PROSPERO. Les chercheurs ont retenu les études cliniques sur le traitement des céphalées par des interventions chirurgicales. Ils ont évalué le risque de biais des études aléatoires et contrôlées. Ils ont également effectué des méta-analyses des résultats au moyen d'un modèle à effets aléatoires pour déterminer le changement moyen regroupé par rapport à l'état de référence et, dans la mesure du possible, pour comparer des sujets traités à des sujets témoins. Résultats: Au total, 18 études respectaient les critères, y compris six études aléatoires et contrôlées, une étude clinique contrôlée, et 11 études non contrôlées auprès de 1 143 patients ayant des pathologies incluant la migraine, la migraine occipitale, la migraine frontale, la céphalée occipitale, la céphalée frontale, la névralgie occipitale et la céphalée cervicogénique. Par rapport à l'état de départ, le traitement chirurgical de la migraine avait réduit la fréquence des céphalées de 13,0 jours par mois (I2 = 0%) un an après l'opération, la gravité des céphalées de 4,16 points sur une échelle de 0 à 10 de huit semaines à cinq ans après l'opération (I2 = 53%) et le score de migraine de 83,1 points de un à cinq ans après l'opération (I2 = 2%). Ces méta-analyses sont limitées par le petit nombre d'études pouvant être analysées, y compris des études comportant de forts risques de biais. Conclusion: Le traitement chirurgical de la migraine assure une diminution cliniquement et statistiquement significative de la fréquence et de la gravité des céphalées, ainsi que des scores de migraine. D'autres études, y compris des études aléatoires et contrôlées comportant un faible risque de biais, devront être exécutées pour mieux préciser les améliorations aux résultats cliniques.

5.
Membranes (Basel) ; 13(3)2023 Feb 28.
Article in English | MEDLINE | ID: mdl-36984676

ABSTRACT

A commercial polydimethylsiloxane (PDMS) membrane was employed to separate the soluble toluene compounds (C7H8) from an aqueous solution via the pervaporation (PV) process. The performance and the efficacy of the PDMS PV membrane were evaluated through the estimation of the permeation flux and separation factor under various operating parameters. The response surface method (RSM) built in the Minitab-18 software was used for the design of the experiment in this study, and the responses of the permeation flux and the separation factor were analyzed and optimized based on the operating conditions. A nonlinear regression analysis was applied to the experimental output and input, and as a result, a quadratic equation model with parameters interactions was obtained as mathematical expressions to predict the permeation flux and separation factor. At the optimal conditions of temperature 30 °C, initial toluene concentration 500 ppm, and feed flowrate 3.5 L/min, the toluene permeation flux and separation factor were 125.855 g/m2·h and 1080, respectively. The feed concentration was the most impactful and significant in the improvement of the permeation flux and separation factor of the PDMS membrane.

6.
Curr Cardiol Rev ; 19(1): e090622205797, 2023.
Article in English | MEDLINE | ID: mdl-35692135

ABSTRACT

PURPOSE: This review aims to summarize and evaluate the most accurate machinelearning algorithm used to predict ischemic heart disease. METHODS: This systematic review was performed following PRISMA guidelines. A comprehensive search was carried out using multiple databases such as Science Direct, PubMed\ MEDLINE, CINAHL, and IEEE explore. RESULTS: Thirteen articles published between 2017 to 2021 were eligible for inclusion. Three themes were extracted: the commonly used algorithm to predict ischemic heart disease, the accuracy of algorithms to predict ischemic heart disease, and the clinical outcomes to improve the quality of care. All methods have utilized supervised and unsupervised machine-learning. CONCLUSION: Applying machine-learning is expected to assist clinicians in interpreting patients' data and implementing optimal algorithms for their datasets. Furthermore, machine-learning can build evidence-based that supports health care providers to manage individual situations who need invasive procedures such as catheterizations.


Subject(s)
Algorithms , Machine Learning , Humans
7.
Membranes (Basel) ; 12(11)2022 Oct 25.
Article in English | MEDLINE | ID: mdl-36363595

ABSTRACT

A developed polydimethylsiloxane (PDMS) membrane was used to separate soluble benzene compounds (C6H6) from an aqueous solution via a pervaporation (PV) process. This membrane was characterized by scanning electron microscopy (SEM), Fourier-transform infrared (FTIR) spectroscopy, contact angle (CA), and energy-dispersive spectroscopy (EDS). To evaluate the performance of the membrane, the separation factor and permeation flux were estimated in various operating conditions, including the feed temperature, initial benzene concentration, and feed flow rate. The experiments to maximize the separation factor and permeation flux were designed using the response surface method (RSM) that is built into Minitab 18. A quadratic model (nonlinear regression equation) was suggested to obtain mathematical expressions to predict the benzene permeation flux and the separation factor according to the effect of the parameters' interaction. The optimization of the PV was performed using an RSM that was based on the analysis of variance (ANOVA). The optimal values of the benzene permeation flux and separation factor were 6.7 g/m2·h and 39.8, respectively, at the optimal conditions of temperature (30 °C), initial concentration of benzene (1000 ppm), and feed flow rate (3.5 L/min). It was found that the feed concentration was the most influential parameter, leading to a significant increase in the permeation flux and separation factor of the PDMS membrane.

8.
Int J Biol Macromol ; 187: 240-250, 2021 Sep 30.
Article in English | MEDLINE | ID: mdl-34303742

ABSTRACT

Chitosan/polyacrylamide hydrogel grafted poly(N-methylaniline) (CS/PACM-gr-PNMA) was good synthesized by chemical oxidative radical polymerization using potassium persulphate (KPS). The obtained polymer samples are characterized using IR and Uv-visible spectroscopy. Both surface properties and thermal stability were studied using XRD, SEM, BET and TGA techniques respectively. The characterized polymeric samples were used as a new sorbent for methyl red (MR). MR as an example of azo-dyes presence as pollutants in industrial wastewater which cause physiological damages was chosen to uptake. The influence of contact time, adsorbent dose, and temperature on the efficiency of CS/PACM-gr-PNMA towards the removal of MR was investigated. The efficacy was equal to 98% through 120 min at room temperature. The obtained data show that, ∆H = -21.478 kJ mol-1, so adsorption process is physically spontaneous and follow Freundlich isotherm. The sorption process of MR on the surface of CS/PACM-gr-PNMA is proceed via the Lagergren pseudo-second order reaction. This confirms the removal mechanism by both chemical and physical adsorption of MR with both unpaired and π electrons present in polymer structure on NH, NH2, and benzene or quinoid units respectively. In addition, it can explain the chemical adsorption type which occurs through sharing between the used adsorbent materials and the dissolved materials beside the physical adsorption.


Subject(s)
Acrylic Resins/chemistry , Aniline Compounds/chemistry , Azo Compounds/isolation & purification , Chitosan/chemistry , Wastewater/chemistry , Water Pollutants, Chemical/isolation & purification , Water Purification , Adsorption , Hydrogels , Kinetics , Models, Chemical
9.
Int J Biol Macromol ; 165(Pt B): 2649-2659, 2020 Dec 15.
Article in English | MEDLINE | ID: mdl-32991898

ABSTRACT

Cancer is an abnormal growth of cells due to the uncontrolled division of the cells and it is the second leading cause of death globally. Immune system malfunction, inflammatory diseases, microbial infection, and oxidative damage are other causes for death. This prompted us to search for non-traditional materials that can be used as anti-cancer, anti-microbial, anti-oxidant and anti-inflammatory agents. Chitosan as a non-toxic, biodegradable, biopolymer with powerful biological activity was grafted with acidified 2-aminothiophenol (2-ATH) using aqueous chemical oxidative copolymerization in presence of ammonium persulphate (APS) as an oxidant at room temperature. The prepared polymeric samples were assembled on silver nanoparticles (AgNPs). The prepared polymeric structure nano-composites were verified by infrared, ultraviolet-visible spectroscopy, X-ray diffraction, thermogravimetric analysis scanning electron microscopy and transmission electron microscopy. The prepared polymeric samples and their composites with AgNPs were screened for their biological activities as anti-cancer properties, anti-microbial, anti-oxidant and anti-inflammatory. The obtained data reveal that chitosan-gr-poly (2-aminothiophenol) (chitosan-gr-p2-ATH) has the most potent anti-oxidant and anti-cancer effects against HepG2 while the composites of p2-ATH with AgNPs and chitosan-gr-p2-ATH with AgNPs have the most potent anti-inflammatory properties.


Subject(s)
Chitosan/chemistry , Metal Nanoparticles/chemistry , Polymers/chemistry , Ammonium Sulfate/chemistry , Ammonium Sulfate/pharmacology , Cell Proliferation/drug effects , Chitosan/therapeutic use , Humans , Immune System/drug effects , Metal Nanoparticles/therapeutic use , Microscopy, Electron, Scanning , Microscopy, Electron, Transmission , Neoplasms/drug therapy , Oxidation-Reduction/drug effects , Polymers/therapeutic use , Silver/chemistry , Staphylococcus aureus
10.
Radiat Prot Dosimetry ; 178(4): 374-381, 2018 Mar 01.
Article in English | MEDLINE | ID: mdl-28981900

ABSTRACT

Poly(acrylate-co-acrylamide) was a synthesis by chemical oxidation polymerization of an aqueous binary mixture of acrylate/acrylamide (1:1 mole ratio) using ammonium persulphate as an initiator at 70°C under the nitrogen atmosphere. The obtained copolymer was introduced for grafting with polyaniline. The grafting process was performed by chemical oxidation polymerization of aniline using ammonium persulphate as an initiator in hydrochloric acid media at 40°C under the nitrogen atmosphere. Poly(acrylic acid-co-acrylamide)-graft-polyaniline samples irradiated with (alpha-particles) at different irradiation doses (0, 2.33, 8.73, 13.09 and 17.46 Gy) at the same linear energy transfer. The change in the morphology, optical properties and the energy gap of poly(acrylic acid-co-acrylamide)-graft-polyaniline samples were studied.


Subject(s)
Acrylamides/chemistry , Alpha Particles , Aniline Compounds/chemistry , Radiation Dosimeters , Acrylates/chemistry , Ammonium Sulfate/chemistry , Materials Testing , Microscopy, Electron, Scanning , Polymerization , Spectrophotometry, Ultraviolet , X-Ray Diffraction
11.
Pflugers Arch ; 469(9): 1073-1091, 2017 09.
Article in English | MEDLINE | ID: mdl-28455748

ABSTRACT

Transepithelial bicarbonate secretion by human airway submucosal glands and surface epithelial cells is crucial to maintain the pH-sensitive innate defence mechanisms of the lung. cAMP agonists stimulate HCO3- secretion via coordinated increases in basolateral HCO3- influx and accumulation, as well as CFTR-dependent HCO3- efflux at the luminal membrane of airway epithelial cells. Here, we investigated the regulation of a basolateral located, DIDS-sensitive, Cl-/HCO3- exchanger, anion exchanger 2 (AE2; SLC4A2) which is postulated to act as an acid loader, and therefore potential regulator of HCO3- secretion, in human airway epithelial cells. Using intracellular pH measurements performed on Calu-3 cells, we demonstrate that the activity of the basolateral Cl-/HCO3- exchanger was significantly downregulated by cAMP agonists, via a PKA-independent mechanism and also required Ca2+ and calmodulin under resting conditions. AE2 contains potential phosphorylation sites by a calmodulin substrate, protein kinase CK2, and we demonstrated that AE2 activity was reduced in the presence of CK2 inhibition. Moreover, CK2 inhibition abolished the activity of AE2 in primary human nasal epithelia. Studies performed on mouse AE2 transfected into HEK-293T cells confirmed almost identical Ca2+/calmodulin and CK2 regulation to that observed in Calu-3 and primary human nasal cells. Furthermore, mouse AE2 activity was reduced by genetic knockout of CK2, an effect which was rescued by exogenous CK2 expression. Together, these findings are the first to demonstrate that CK2 is a key regulator of Cl--dependent HCO3- export at the serosal membrane of human airway epithelial cells.


Subject(s)
Bicarbonates/metabolism , Casein Kinase II/metabolism , Chloride-Bicarbonate Antiporters/metabolism , Chlorides/metabolism , Nasal Mucosa/metabolism , Animals , Cell Line , Cell Line, Tumor , Cell Membrane/metabolism , Cyclic AMP/metabolism , Epithelial Cells/metabolism , HEK293 Cells , Humans , Hydrogen-Ion Concentration , Mice
12.
J Physiol ; 594(6): 1643-61, 2016 Mar 15.
Article in English | MEDLINE | ID: mdl-26574187

ABSTRACT

Hypercapnia is clinically defined as an arterial blood partial pressure of CO2 of above 40 mmHg and is a feature of chronic lung disease. In previous studies we have demonstrated that hypercapnia modulates agonist-stimulated cAMP levels through effects on transmembrane adenylyl cyclase activity. In the airways, cAMP is known to regulate cystic fibrosis transmembrane conductance regulator (CFTR)-mediated anion and fluid secretion, which contributes to airway surface liquid homeostasis. The aim of the current work was to investigate if hypercapnia could modulate cAMP-regulated ion and fluid transport in human airway epithelial cells. We found that acute exposure to hypercapnia significantly reduced forskolin-stimulated elevations in intracellular cAMP as well as both adenosine- and forskolin-stimulated increases in CFTR-dependent transepithelial short-circuit current, in polarised cultures of Calu-3 human airway cells. This CO2 -induced reduction in anion secretion was not due to a decrease in HCO3 (-) transport given that neither a change in CFTR-dependent HCO3 (-) efflux nor Na(+) /HCO3 (-) cotransporter-dependent HCO3 (-) influx were CO2 -sensitive. Hypercapnia also reduced the volume of forskolin-stimulated fluid secretion over 24 h, yet had no effect on the HCO3 (-) content of the secreted fluid. Our data reveal that hypercapnia reduces CFTR-dependent, electrogenic Cl(-) and fluid secretion, but not CFTR-dependent HCO3 (-) secretion, which highlights a differential sensitivity of Cl(-) and HCO3 (-) transporters to raised CO2 in Calu-3 cells. Hypercapnia also reduced forskolin-stimulated CFTR-dependent anion secretion in primary human airway epithelia. Based on current models of airways biology, a reduction in fluid secretion, associated with hypercapnia, would be predicted to have important consequences for airways hydration and the innate defence mechanisms of the lungs.


Subject(s)
Bicarbonates/metabolism , Carbon Dioxide/metabolism , Chlorides/metabolism , Cyclic AMP/metabolism , Cystic Fibrosis Transmembrane Conductance Regulator/metabolism , Hypercapnia/metabolism , Respiratory Mucosa/metabolism , Cell Line , Cells, Cultured , Humans , Ion Transport , Signal Transduction , Sodium/metabolism
13.
IEEE Trans Syst Man Cybern B Cybern ; 42(4): 993-1005, 2012 Aug.
Article in English | MEDLINE | ID: mdl-22623430

ABSTRACT

This paper presents our response to the first international challenge on facial emotion recognition and analysis. We propose to combine different types of features to automatically detect action units (AUs) in facial images. We use one multikernel support vector machine (SVM) for each AU we want to detect. The first kernel matrix is computed using local Gabor binary pattern histograms and a histogram intersection kernel. The second kernel matrix is computed from active appearance model coefficients and a radial basis function kernel. During the training step, we combine these two types of features using the recently proposed SimpleMKL algorithm. SVM outputs are then averaged to exploit temporal information in the sequence. To evaluate our system, we perform deep experimentation on several key issues: influence of features and kernel function in histogram-based SVM approaches, influence of spatially independent information versus geometric local appearance information and benefits of combining both, sensitivity to training data, and interest of temporal context adaptation. We also compare our results with those of the other participants and try to explain why our method had the best performance during the facial expression recognition and analysis challenge.

14.
Bioresour Technol ; 99(13): 5947-50, 2008 Sep.
Article in English | MEDLINE | ID: mdl-18054484

ABSTRACT

The essential oil of Artemisia judaica L., grown on Sinai Peninsula of Egypt, was extracted via hydrodistillation. Chromatographic separation on repeated silica gel columns led to isolate two compounds namely piperitone and trans-ethyl cinnamate. Insecticidal, antifeedant and antifungal properties of the isolated compounds were examined. Both compounds showed pronounced insecticidal and antifeedant activity against the third instar larvae of Spodoptera littoralis (Boisd). trans-Ethyl cinnamate (LD(50)=0.37 microg/larva) was more toxic than piperitone (LD(50)=0.68microg/larva). The two isolated compounds revealed antifeedant activity in a concentration dependent manner, with complete feeding inhibition at a concentration of 1,000microg/ml. When tested for antifungal activity against four plant pathogenic fungi, the isolated compounds exhibited a moderate to high activity.


Subject(s)
Artemisia/chemistry , Oils, Volatile/chemistry , Spodoptera/drug effects , Animals , Antifungal Agents/isolation & purification , Antifungal Agents/pharmacology , Chromatography , Egypt , Fungi/drug effects , Fungi/growth & development , Insecticides/isolation & purification , Insecticides/toxicity , Larva/drug effects , Oils, Volatile/isolation & purification , Oils, Volatile/toxicity , Plant Extracts/chemistry , Plant Extracts/isolation & purification , Plant Extracts/toxicity , Silica Gel , Silicon Dioxide , Spodoptera/growth & development
16.
Folia Microbiol (Praha) ; 48(2): 261-8, 2003.
Article in English | MEDLINE | ID: mdl-12800514

ABSTRACT

The cryptococcal polysaccharide antigen was detected in 10 cerebrospinal fluid (CSF) and 23 serum samples from cryptococcal meningitis and intestinal cryptococcosis by the cryptococcal antigen latex agglutination system (CALAS). CALAS titers in CSF and serum samples of cryptococcal meningitis ranged over 8-2048 and 32-2048, respectively, while in cases of intestinal cryptococcosis, serum titers ranged over 8-2048. The isolates of yeast Cryptococcus neoformans were determined to be of serotype A or of the A/D pair. The total leukocyte count and biochemical parameters in CSF were significantly increased as indicators of microbial infection. Furthermore, the in vitro change of the teleomorph (sexual state) to the anamorph (asexual state) was also detected and the teleomorph state changed in vivo to the encapsulated anamoph state which is more virulent during infection in vivo than the yeast-like noncapsulated form. Two primers for internal transcribed spacer (ITS) regions of ribosomal DNA were used for molecular detection of C. neoformans. After PCR amplification, a DNA band of 415 bp, visualized on agarose gel, indicated the presence of C. neoformans cells in the tested CSF and serum samples. The primer sensitivity was also characterized using purified yeast chromosomal DNA as template; it was about 20 pg or more chromosomal DNA which represents about 10 cells of C. neoformans. The primers were also specific for ITS regions of C. neoformans and gave negative results with Candida albicans and E. coli chromosomal DNA templates.


Subject(s)
Cryptococcosis/microbiology , Cryptococcus neoformans/classification , Intestinal Diseases/microbiology , Meningitis, Cryptococcal/microbiology , Adolescent , Adult , Child , Child, Preschool , Cryptococcosis/diagnosis , Cryptococcus neoformans/genetics , Cryptococcus neoformans/isolation & purification , DNA, Fungal/blood , DNA, Fungal/cerebrospinal fluid , Egypt , Humans , Intestinal Diseases/diagnosis , Latex Fixation Tests , Meningitis, Cryptococcal/diagnosis , Middle Aged , Mycological Typing Techniques , Polymerase Chain Reaction/methods , Polysaccharides/blood , Polysaccharides/cerebrospinal fluid , Sensitivity and Specificity , Serotyping
17.
Appl Microbiol Biotechnol ; 56(1-2): 157-64, 2001 Jul.
Article in English | MEDLINE | ID: mdl-11499924

ABSTRACT

The methylotrophic yeast Hansenula polymorpha HM1-39 (ura 3 and leu 2) was used as a host strain for the expression of the Fab fragment of the MAK33 monoclonal antibody. The MAK33 antibody reacts specifically with creatine kinase-M. The cDNA of kappa and gamma chains were inserted between the FMD or MOX promoter and the MOX terminator within the expression plasmids. In addition, the secretion signal sequence of the mating factor-alpha (prepro segment) and a fragment from glucoamylase with its secretion signal peptide, were also inserted in the expression plasmids for efficient secretion and production of the MAK33 monoclonal antibody. The co-expression of kappa and gamma chains was achieved by double transformation with kappa and then with gamma chain-expressing plasmids. The cells of H. polymorpha HM1-39 showed high mitotic stability and both uracil+ and leucine+ phenotypic stability after double transformation. Northern analysis showed a high rate of transcription of either kappa or gamma chain mRNA but not both, when the cells were grown in an induction medium. Protein analysis of double-transformed cells showed the monomers of the MAK33 antibody (kappa and gamma chains) were not assembled into a heterodimeric functional form. The expressed proteins of light and heavy chains represent about 11-12% of total cell protein and are found more inside than outside the cell. The expressed monomers show antigen-binding affinity in the Ouchterlony diffusion test; and the binding activity exhibited by cell-free extract was more than that of the cell culture supernatant.


Subject(s)
Antibodies, Monoclonal/biosynthesis , Creatine Kinase/immunology , Pichia/genetics , Recombinant Proteins/biosynthesis , Animals , Blotting, Northern , Immunoglobulin gamma-Chains/biosynthesis , Immunoglobulin kappa-Chains/biosynthesis , Mice , Transformation, Genetic
18.
Folia Microbiol (Praha) ; 44(6): 689-94, 1999.
Article in English | MEDLINE | ID: mdl-11097028

ABSTRACT

A PCR amplification was performed to detect Neisseria meningitidis insertion sequence 1106 (IS-1106) in the human CerebroSpinal Fluid (CSF) in cases of meningitis. The study included 27 CSF samples from suspected meningitis patients. Although the inflammatory response in most of the samples was slightly increased, the results showed that 7 (26%) and 8 (30%) CSF samples were diagnosed as meningococcal meningitis by Gram staining and by culture, respectively. The primers of the IS-1106 were used for direct diagnosis of N. meningitidis in the human spinal fluid after a minor treatment of the CSF samples. The sample was diagnosed as meningococcal meningitis, if a DNA band of about 600 bp was detected in the ethidium bromide-stained agarose gel. The 27 CSF samples were analyzed in a random manner. Of these, 18 samples including the Gram staining- and culture-positive samples were also positive in PCR amplification. However, a CSF sample, which was diagnosed to be meningococcal meningitis in culture was negative in both Gram staining and PCR analysis. The specificity of the IS-1106 primers was determined to be 95%, with 100% sensitivity in comparison to Gram staining and culture. The primers were sensitive to 10 pg or more of meningococcal DNA. In addition, the PCR amplification showed high predictive values (89 and 100%) in diagnosing meningitis in patients that were negative and positive responders when tested by culture and by Gram staining. In conclusion, the PCR amplification of IS-1106 of N. meningitidis is specific and sensitive to both culture-positive and -negative meningococcal meningitis. Hence, PCR assay is highly recommended for use in a rapid diagnosis of suspected meningitis patients.


Subject(s)
Cerebrospinal Fluid/microbiology , Neisseria meningitidis/genetics , Neisseria meningitidis/isolation & purification , Polymerase Chain Reaction/methods , Base Sequence , DNA Primers/genetics , Humans , Meningitis, Meningococcal/cerebrospinal fluid , Meningitis, Meningococcal/diagnosis , Meningitis, Meningococcal/microbiology
19.
Regul Pept ; 46(3): 543-7, 1993 Jul 23.
Article in English | MEDLINE | ID: mdl-8210513

ABSTRACT

The effect of neurotensin (NT) on proline absorption across rat jejunum was investigated using the single-pass perfusion technique. This study showed that intravenous administration of NT produced a dose-dependent inhibition of proline absorption. Thus, NT at a 0.16 pmol/kg/min concentration gave 10% decrease in proline absorption while 0.32 and 1.6 pmol/kg/min concentration gave 31% and 45% decrease, respectively. In the absence of Na, proline absorption decreased to 77% from control values. No change in proline absorption was noticed when NT at a concentration of 0.32 pmol/kg/min was intravenously injected in the absence of sodium from the perfusion solution. Water absorption did not show significant changes (P > 0.05) in presence or absence of NT. Moreover, NT did not produce a significant change (P > 0.2) in intracellular proline accumulation. NT inhibited proline absorption through an indirect mechanism that is Na-dependent and independent of changes in water absorption.


Subject(s)
Intestinal Absorption/drug effects , Jejunum/drug effects , Neurotensin/pharmacology , Proline/antagonists & inhibitors , Animals , Dose-Response Relationship, Drug , Female , In Vitro Techniques , Injections, Intravenous , Jejunum/cytology , Neurotensin/administration & dosage , Proline/metabolism , Rats , Rats, Sprague-Dawley , Sodium/metabolism
20.
Respiration ; 36(4): 177-82, 1978.
Article in English | MEDLINE | ID: mdl-674863

ABSTRACT

We have demonstrated the reliability of the planimetric method for the determination of total lung capacity (TCL) in children aged 4-16 in comparison with TLC measured by the plethysmography method. We have found power function formulas to be of greater potential usefulness than linear, logarithmic or exponential formulas for calculating TLC by the planimetric technique.


Subject(s)
Lung Volume Measurements/methods , Total Lung Capacity/methods , Adolescent , Body Surface Area , Child , Child, Preschool , Female , Humans , Male , Plethysmography, Whole Body , Tomography, X-Ray
SELECTION OF CITATIONS
SEARCH DETAIL
...