Mechanical performance and thermal stability of hardened Portland cement-recycled sludge pastes containing MnFe2O4 nanoparticles.

This study focused on investigating the possibility of using different ratios (5, 10, 15 mass%) of recycled alum sludge (RAS) as partial replacement of ordinary Portland cement (OPC), to contribute to solving the problems encountered by cement production as well as stockpiling of large quantities of water-treated sludge waste. MnFe2O4 spinel nanoparticles (NMFs) were used to elaborate the mechanical characteristics and durability of different OPC-RAS blends. The outcomes of compressive strength, bulk density, water absorption, and stability against firing tests fastened the suitability of utilization of RAS waste for replacing OPC (maximum limit 10%). The inclusion of different doses of NMFs nanoparticles (0.5, 1 and 2 mass %) within OPC-RAS pastes, motivates the configuration of hardened nanocomposites with improved physico-mechanical characteristics and stability against firing. Composite made from 90% OPC-10% RAS-0.5% NMFs presented the best characteristics and consider the optimal choice for general construction applications. Thermogravimetric analysis (TGA/DTG), X-ray diffraction analysis (XRD), and scanning electron microscope (SEM) techniques. affirmed the positive impact of NMFs particles, as they demonstrated the formation of enormous phases as ilvaite (CFSH), calcium silicate hydrates (CSHs), MnCSH, Nchwaningite [Mn2 SiO3(OH)2 H2O], [(Mn, Ca) Mn4O9⋅3H2O], calcium aluminosilicate hydrates (CASH), Glaucochroite [(Ca, Mn)2SiO4, and calcium ferrite hydrate (CFH). These hydrates boosted the robustness and degradation resistance of the hardened nanocomposites upon firing.

Design of Chronomodulated Drug Delivery System of Valsartan: In Vitro Characterization.

The aim of the present study was to design and evaluate a chronomodulated time-clock pulsatile tablets of valsartan to release it after a certain lag time, independent of the gastrointestinal pH, in its absorption window to cope with the circadian rhythm of human body for blood pressure elevation. Core tablets were prepared by direct compression of a homogenous mixture of valsartan, Avicel PH101, croscarmellose sodium, magnesium stearate and Aerosil. The core tablets were then sprayed coated with a sealing layer formed of ethyl cellulose that was subsequently coated with a release-controlling layer. Three different aqueous dispersions namely; carnauba wax or beeswax or a mixture in a ratio of 2.5:1, respectively, were used to form five time-clock tablet formulations having the release controlling layer with different thickness {B5, B10, B20, BW5 and CW5}. Quality control testing were carried out to the core tablets. Differential scanning calorimetry was also performed to detect the possible drug excipient interaction in the core tablet formulation. The release was carried out, for the prepared time-clock tablet formulations, in 0.1 N hydrochloric acid for the first 2 h, followed by phosphate buffer (pH 6.8) for 4.5 h. The effect of pH on valsartan release was studied through a release study in 0.1 N hydrochloric acid for 6.5 h. Two phase dissolution study was performed to the selected time-clock tablet formulation to predict the drug permeation through the gastrointestinal tract. Stability study of the selected formula was performed at 25°/60% RH and at 40°/75% RH for 3 months. Results showed that a release-controlling layer composed of a mixture of carnauba wax and beeswax in a ratio of 2.5:1 showed a reasonable release lag time. The release lag time of the tablets increased with the increase of the coat thickness, thus B20>B10>B5 with corresponding lag time values of 4.5, 3 and 2.5 h, respectively. Selected B5 tablet formula exhibited a reasonable lag time after which the highest, complete % drug release at pH 6.8 was obtained. In addition, a good partitioning of valsartan, between the aqueous and organic phases in a ratio of 1:7, was observed. The selected formula was stable for at least 3 months under standard long-term and accelerated storage conditions. In conclusion, in vitro studies revealed that the novel time-clock system could be used successfully to deliver valsartan in a pulsatile pH-independent manner. It provided a desirable lag time followed by a rapid and complete drug release accompanied by an expected effective permeation through the biological membranes upon release in the duodenum; the window of absorption, as indicated by the two phase release study.

Binding of several phenothiazine neuroleptics to a common binding site of alpha 1-acid glycoprotein, orosomucoid.

The interaction of several phenothiazine neuroleptics with alpha 1-acid glycoprotein was investigated using circular dichroism and equilibrium dialysis techniques. For chlorpromazine only, one high-affinity binding site of the protein was found. The binding of the drug to this single site generated typical polyphasic extrinsic Cotton effects. Since several other phenothiazine neuroleptics gave qualitatively comparable extrinsic Cotton effects in the presence of alpha 1-acid glycoprotein and potently inhibited the binding of chlorpromazine to the single site, it was concluded that all phenothiazine derivatives investigated bound preferentially to only one common binding site of the alpha 1-acid glycoprotein molecule.

Application of some polymers in the physiocochemical design of tablet formulation.

Polyethylene glycol 4000 did not apprecialbly affect the rate of drug release from tablets. The use of sodium alginate the a tablet binder showed variable effects on the rate of drug release from the tablet i.e. The incorporation of only 2.5% of sodium alginate caused enhancement in the release rate of the drug based on its action as disintegration inducer. On the other hand, the incorporation of 20, 35 and 50% of sodium alginate showed a pronounced retardation in the rate of drug release from the tablets. This retardation was more pronounced in acid than in alkaline media. Accordingly, sodium alginate could be favourably suggested as tablet binder when retarded gastric absorption is the therapeutic aim required. Carbopol 940 when used as a tablet binder in a concentration of 2.5%, showed a marked enhancement of the release rate of the drug. On the contrary, it exerted a remarkable retardation in the rate of drug release from the tablets when incorporated in the relatively large proportions of 20, 35 and 50%. This retardation was more pronounced in alkaline than in acid media. Accordingly, Carbopol 940 would be favourably suggested in the physiocohemical design of prolonged-release tablet formulations.

Asymptomatic bacteriuria in school children in a rural area, Egypt.

Forty hundred and fifty urine samples collected from school children in a rural area were screened for the presence of significant bacteriuria. The incidence of asymptomatic bacteriuria was found to be 7% with Predominance in females (11%) than in males (3.6%). From the total bacterial isolates E. coli were isolated in 18% of cases, Co-agulase positive staphylococci in 30%, co-agulase negative staphylococci in 15%, streptococcus pyogenes in 6%, Klebsiella species in 9% and enterococci in 21% of cases. There was no difference between the incidence of asymptomatic bacteriuria (ABU) in younger children than in older ones. We recommended a routine screening for ABU among school children for the early diagnosis and management of such cases.

A specialized hospital information system.

Modern information technology offers new opportunities for the storage and manipulation of hospital information. A computer-based hospital information system dedicated to urology and nephrology was designed and developed in our centre. It involves in principle, the employment of a program that allows the analysis of non-restricted non-codified texts, for the retrieval and processing of clinical data, and operation by non-computer specialized hospital staff. This Hospital Information System now plays a vital role for the provision of an efficient, good quality service and is used now in daily routine and research work in this hospital. This paper describes this specialized hospital information system.

Understanding clinical narrative text.

A linguistic analysis of the narrative which appears in patient documents, in the domain of urology, has shown that the information is conveyed by a small number of semantic statement types composed of syntactic combinations of medical and English word classes. It has been shown that words from different classes occurring in the diagnosis for the patient disease follow some regular grammatical rules. This impressive linguistic regularity in clinical narrative has made it encouraging to develop a recognizer which is capable of recognizing disease diagnosis in the narrative clinical documents in the domain of urology. The recognizer was implemented using the C language. This recognizer output information which could be refined to a form suitable for management by a database management system for further computerized information processing.

Case-based reasoning algorithms applied in a medical acquisition tool.

The knowledge of clinical medicine can, efficiently and effectively, be elicited and encoded automatically as cases. The developed knowledge base often contains some redundancy. The cost can be tolerated as it affects neither the performance of the system nor the integrity of the knowledge. The advantages are simplicity in development and reliability in performance.

A computer-based system for urology and nephrology.

Modern technology offers new opportunities for the storage and manipulation of hospital information. A computer-based system for urology and nephrology has been designed and developed in this centre. It uses a program that allows the analysis of unrestricted non-codified texts and the operation by hospital staff who have had no more than minimal computer training. The potential of such a system is outlined and a comparison is made with other existing systems. Future prospects and potential lines of development are presented.