Mohamed Zaki

NixMn0.8-xMg0.2Fe2O 4; 0.1 ≤ x ≤ 0.35 was prepared by standard ceramic technique at sintering temperature 1200 °C using heating / cooling rate 4 °C/min. The samples were irradiated by Nd YAG pulsed laser with energy of the pulse 250 mJ. X-ray diffractograms reveal cubic spinel structure for all the samples before and after laser irradiation. After laser irradiation, better crystallinity was obtained in a form of an increase in the calculated crystal size. This increase was discussed as due to the change in the valence of some ions like Fe3+, Ni2+ and Mn2+. The conductivity of all the investigated samples decreases after laser irradiation and becomes temperature independent for a wider range than that before irradiation. This was ascribed to electron rearrangement after laser irradiation. Accordingly, these ferrites are recommended to be useful in electronic devices. © 2011 Elsevier B.V. All rights reserved.

Aim. The aim of this study was to compare combined spinal epidural (CSE), epidural (E) and IV pethidine analgesia and their effects on the mother, fetus, newborn and the labor course. Methods. This is a prospective parallel single blind study, where 60 women in active labor were recruited and were allocated to five subgroups to receive analgesia by different routes. The mother and the fetus were assessed. The results were recorded and compared using Visual Analogue Scale (VAS) and modified Bromage scale for motor block, in addition to other clinical findings. Results. The duration of first stage of labor was significantly longer in the E group, compared with the CSE and IV pethidine groups. When the pain control achieved by CSE bupivacaine and lidocaine was compared with the corresponding epidural, it was found that the first technique achieved better pain control. Women who received pethidine had higher incidence of nausea and vomiting compared to those received CSE or E analgesia. There was no significant difference between the five groups with respect to other side effects. Conclusion. Regional analgesia especially CSE using bupivacaine or lidocaine is a safe effective method for analgesia in labor with relative better efficacy of bupivacaine.

In this work the retardation of Ehrlich tumor growth implanted in mice was studied by employing 4.5 Hz magnetic field. Eighty female Balb/c mice were used, twenty as normal group; the other sixty mice were inoculated with Ehrlich tumor, then they were divided equally into three groups namely A, B and C. Group A (control group) animals were not exposed to the magnetic field. The tumors in the thigh of the animals of group B were exposed to 4.5 Hz, 2 Gauss square wave magnetic field by using a small solenoid connected to a power square wave generator. Group C animals were whole body exposed inside a large solenoid to 4.5 Hz, 2 Gauss square wave magnetic field. Both groups B and C were exposed for a period of 2 weeks at a rate 2 hours per day. Tumor volume, survival period, histological examination and dielectric relaxation of the tumor were measured to investigate the activity of the tumor of the exposed and the unexposed animals. The results indicated that exposing the tumor tissue to 4.5 Hz square wave magnetic field for 2 weeks at a rate 2 hours/day inhibited tumor growth and increased the survival period of the animals. However, group B showed more improvements than did group C. This was attributed to some distortions in the square waveform in the large solenoid (group C). By comparing data from current and previous work, it was concluded that the use of magnetic waves showed better results over previously published work using amplitude modulated electromagnetic waves with the same frequency.

Abdominal venous thrombosis may present as splanchnic venous thrombosis (SVT) (occlusion of portal, splenic, superior or inferior mesenteric veins) or Budd- Chiari Syndrome (BCS) (thrombosis of inferior vena cava and/or hepatic veins). The aim of this review is to report the scanty data available for SVT in the South Mediterranean area. In one Egyptian study, the possible circumstantial risk factors for portal vein thrombosis (PVT) were found in 30% of cases: 19% neonatal sepsis, 8.7% umbilical catheterization, 6% severe gastroenteritis and dehydration. Another Egyptian study concluded that hereditary thrombophilia was common in children with PVT (62.5%), the commonest being factor V Leiden mutation (FVL) (30%). Concurrence of more than one hereditary thrombophilia was not uncommon (12.5%). The first international publication on hepatic veno-occlusive disease (VOD) in Egypt was in 1965 in children who rapidly develop abdominal distention with ascites and hepatomegaly. This disease was more frequent in malnourished children coming from rural areas; infusions given at home may contain noxious substances that were hepatotoxic and infections might play a role. VOD of childhood is rarely seen nowadays. Data from South Mediterranean area are deficient and this may be attributable to reporting in local medical journals that are difficult to access. Medical societies concerned with this topic could help distribute this information.

Abdominal venous thrombosis may present as splanchnic venous thrombosis (SVT) (occlusion of portal, splenic, superior or inferior mesenteric veins) or Budd- Chiari Syndrome (BCS) (thrombosis of inferior vena cava and/or hepatic veins). The aim of this review is to report the scanty data available for SVT in the South Mediterranean area. In one Egyptian study, the possible circumstantial risk factors for portal vein thrombosis (PVT) were found in 30% of cases: 19% neonatal sepsis, 8.7% umbilical catheterization, 6% severe gastroenteritis and dehydration. Another Egyptian study concluded that hereditary thrombophilia was common in children with PVT (62.5%), the commonest being factor V Leiden mutation (FVL) (30%). Concurrence of more than one hereditary thrombophilia was not uncommon (12.5%). The first international publication on hepatic veno-occlusive disease (VOD) in Egypt was in 1965 in children who rapidly develop abdominal distention with ascites and hepatomegaly. This disease was more frequent in malnourished children coming from rural areas; infusions given at home may contain noxious substances that were hepatotoxic and infections might play a role. VOD of childhood is rarely seen nowadays. Data from South Mediterranean area are deficient and this may be attributable to reporting in local medical journals that are difficult to access. Medical societies concerned with this topic could help distribute this information.

Ni ferrite nanoparticles were prepared using citrate method. XRD pattern revealed the formation of the samples as synthesized in the spinel cubic structure. Silver doping effect on the magnetic properties of Ni ferrite was investigated. The lattice parameter was slightly increased while the values of the Curie temperature decreased with increasing Ag content. The magnetic susceptibility was measured using Faraday's method and the calculated magnetic constants were reported. The data showed that χ M and effective magnetic moment decrease with increasing Ag content. © 2011 Elsevier Masson SAS. All rights reserved.

The La0.8Ca0.2-x□xMnO3, (x = 0-0.20) compounds were prepared by the solid-state reaction. X-ray diffraction (XRD) and magnetic measurements were used to investigate the calcium-vacancy effect on the physical properties. The XRD data have been analyzed by Rietveld refinement technique. Samples with x = 0, 0.05 and 0.10 are found to be single phase and crystallize in orthorhombic symmetry with Pnma space group. Moreover, for x = 0.15 and 0.20 samples, the refinement has revealed the coexistence of both Pnma orthorhombic and R3̄c rhombohedral phases. The magnetic study has showed that the magnetization exhibits maximum at x = 0.15 and minimum at x = 0.2. Such behavior was interpreted in terms of orthorhombic distortion contribution, which is related to the orthorhombic structure, leading to magnetization decrease. In addition, maximum magnetic entropy change (ΔSM) for x = 0 sample was found to reach ∼4.1 J/kg K under an applied magnetic field of 5 T, which is very sufficient for potential application in magnetic refrigeration. For the same applied magnetic field (μ0H = 5 T), the Relative Cooling Power (RCP) values are found to vary between 270 and 300 J/kg. As consequence, the La0.8Ca 0.2-x□xMnO3compounds can be used as a composite for magnetic refrigeration in the [175-183] K temperature range. © 2011 Elsevier B.V. All rights reserved.

A series of block poly(ester-ether urethane)s, poly (PHB/PCL-PEG-PCL), based on poly(3-hydroxybutyrate) (PHB-diol), as hard segments, and poly(ε-caprolactone)-bpoly( ethylene glycol)-b-poly(ε-caprolactone), (PCL-PEGPCL) triblock copolydiol, as soft segments, were prepared using 1,6-hexamethylene diisocyanate (HDI), as non-toxic connecting agent. Polyurethanes block copolymer was synthesized from bacterial PHB and PCL-PEG-PCL blocks. The chemical structure and molecular weights of polymers prepared were characterized by FTIR, 1H NMR and GPC. The effect of chemical structure on the thermal and mechanical properties was studied by differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and tensile testing. The DSC results revealed that poly(PHB/ PCL-PEG-PCL) urethanes are semi-crystalline with two crystallizable PHB and PCL-PEG-PCL blocks. The thermal stability of the urethanes is less than neat PHB. The results of tensile testing showed that the extensibility of PHB is largely enhanced by the incorporation of PCL-PEG-PCL soft segments. Activation energy Ea, as a kinetic parameter of thermal decomposition, was estimated by each of the Ozawa and Kissinger methods. Close values of activation energy were obtained by both methods. The swelling behaviour of the copolymers was also investigated. © 2010 Springer Science+Business Media B.V.

OBJECTIVE: Three commonly used antihelmenthic drugs including Dormectin (0.2 mg/kg), Ivermectin (0.2 mg/kg) and Levamisole (7.5 mg/kg) were examined for their antihelmenthic efficacy against experimental Trichinella spiralis infection in rats.

METHODS: One hundred and twenty rats were orally infected with 500 T. spiralis larvae. Drugs were tested against adult worms at 4th day, against migrating larvae at 10th days and against encysted larvae at 35th day post infection (dpi). Rats were sacrificed five days post treatment. Mature worms and migrating larvae counts were detected.

RESULTS: Significant effect was detected in rats treated with Dormectin and Ivermectin compared to non-treated controls. Dormectin showed an efficacy of 97.75% and 86.23% in eliminating both mature worms and migrating larvae respectively. Ivermectin showed an efficacy of 94.99% and 83.85% respectively. However, Levamisole was the least effective drug; its efficacy was 4.83% and 3.57% against mature worms and migrating larvae respectively.

CONCLUSION: All of the tested drugs failed to inhibit the encysted larvae in the diaphragms. Moreover, T. spiralis infection in rats reduced significantly the values of total proteins, and albumin while globulin, urea and creatinine values were significantly increased together with AST and ALT activities.