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In this article, an ultrawideband (UWB) antenna with triple band-rejection characteristics is proposed. The antenna is compact with size of 22.5 × 24 mm2. Matching between a sector-disk shaped radiating patch and the 50-Ω microstrip line is manipulated through a proximity-feed technique. An elliptically-shaped aperture is etched in the ground plane to enhance the antenna bandwidth. Double shunt stubs are used to get more enhancement of the impedance bandwidth of the antenna. The band notches at WiMAX of 3.3–3.9 GHz, lower WLAN of 5.15–5.35 GHz, and upper WLAN of 5.725–5.825 GHz are realized by embedding three elements; a reversed F-shaped slot etched off in the patch, a reversed U-shaped slot etched off in the feed line, and adding a parasitic flipped C-shaped strip around the patch, respectively. The antenna is fabricated and the experimental data show that the designed antenna has an impedance bandwidth of 3.2–11.6 GHz for VSWR less than 2, except at three frequency stop-bands of 3.20–4.19, 5.02–5.32, and 5.51–6.10 GHz. Curve fitting formulations to describe the influences of the embedded structures on the corresponding notched frequencies are obtained by using a second-order polynomial. Moreover, physical lumped elements of an electrical equivalent circuit model of the proposed antenna are obtained using a rational function approximation based on the vector fitting technique. The antenna provides almost omnidirectional patterns, relatively flat gain, and high radiation efficiency over the entire UWB frequency excluding the rejected bands. © 2014 Wiley Periodicals, Inc. Microwave Opt Technol Lett 56:646–654, 2014

The diagnosis of inflammatory breast cancer (IBC) is largely clinical and therefore inherently somewhat subjective. The objective of this study was to evaluate the diagnosis of IBC at two centers in North Africa where a higher proportion of breast cancer is diagnosed as IBC than in the United States (U.S.). Physicians prospectively enrolled suspected IBC cases at the National Cancer Institute (NCI) – Cairo, Egypt, and the Institut Salah Azaiz (ISA), Tunisia, recorded extent and duration of signs/symptoms of IBC on standardized forms, and took digital photographs of the breast. After second-level review at study hospitals, photographs and clinical information for confirmed IBC cases were reviewed by two U.S. oncologists. We calculated percent agreement between study hospital and U.S. oncologist diagnoses. Among cases confirmed by at least one U.S. oncologist, we calculated median extent and duration of signs and Spearman correlations. At least one U.S. oncologist confirmed the IBC diagnosis for 69% (39/50) of cases with photographs at the NCI-Cairo and 88% (21/24) of cases at the ISA. All confirmed cases had at least one sign of IBC (erythema, edema, peau d'orange) that covered at least one-third of the breast. The median duration of signs ranged from 1 to 3 months; extent and duration of signs were not statistically significantly correlated. From the above-mentioned outcomes, it can be concluded that the diagnosis of a substantial proportion of IBC cases is unambiguous, but a subset is difficult to distinguish from other types of locally advanced breast cancer. Among confirmed cases, the extent of signs was not related to delay in diagnosis.

Background: Despite recent improvements, many patients with aggressive non-Hodgkin’s lymphoma (NHL) ultimately succumb to their disease. Therefore, improvements in front-line chemotherapy of aggressive NHL are needed. Gemcitabine is active in lymphoma. Methods: We performed a randomized phase II trial of the addition of gemcitabine to standard CHOP chemotherapy with or without rituximab [(R)CHOP]. The trial was also designed to determine the maximal tolerated dose (MTD) of gemcitabine in this combination. Patients with previously untreated aggressive NHL were randomized to receive either eight cycles of (R)CHOP given every 3 wk or (R)CHOP combined with gemcitabine [Gem-(R)CHOP]. Results: Twentyfive patients were enrolled in the trial before early closure. Twelve were randomized to Gem-(R)CHOP and 13 to (R)CHOP. MTD of gemcitabine was 800 mgUm 2 given on days 1 and 8; dose-limiting toxicity was hematologic. Five patients (42%) treated with Gem-(R)CHOP achieved complete response in comparison with 10 (77%) treated with (R)CHOP. Median time to treatment failure was 1.5 yr for Gem-(R)CHOP and 3.1 yr for (R)CHOP. Three patients receiving Gem-(R)CHOP had serious pulmonary toxicity, when compared to none receiving (R)CHOP. One patient died of pneumonitis. Conclusions: In this group of patients, addition of gemcitabine did not seem to improve outcomes. Gem-(R)CHOP in previously untreated patients with aggressive NHL occasionally results in severe, potentially fatal, pulmonary toxicity.

Aims To test the efficacy of WAY-133537 for the treatment of overactive bladder (OAB) in a chronic paraplegic rat model. Materials and Methods Forty-eight female Sprague–Dawley rats were used in this study. Six animals served as normal controls (without spinal cord transaction (ST)), while 42 rats underwent ST at the 10th thoracic vertebra. Two weeks after ST, cystometrogram (CMG) was performed in six randomly chosen animals to ensure the development of neurogenic detrusor overactivity. The remaining 36 rats were divided into three equal groups, 12 received the vehicle as “paraplegic controls,” 12 received WAY-133537 0.3 mg/kg, and 12 received WAY-133537 3 mg/kg. Each “paraplegic control” and treatment group was further divided into two sub-groups (n = 6), with CMG at 3 and 4 weeks after ST, respectively. Results Two weeks after ST, all “vehicle control” rats developed detrusor overactivity with a mean frequency of 0.96 and 1.48 contractions/min and amplitude of 22.96 and 31.22 cm H2O with 1- and 2-week treatment, respectively. Neurogenic detrusor overactivity disappeared from 50% of rats that received WAY-133537 0.3 mg/kg for 1 week, and frequency decreased to 0.41 contractions/min. After 2 weeks of treatment, detrusor overactivity vanished from 67% of the animals with even further reduction in the frequency of detrusor overactivity (0.22 contractions/min, P

Background: The non-structural protein 3 (NS3P) of hepatitis C virus (HCV) genome was linked to the neoplastic transformation of normal hepatocytes in chronically infected patients. However, the exact mechanisms involved in this process are unidentified yet, especially in the Egyptian population where the commonest type is genotype 4. Methods: We investigated 32 HCV reverse transcriptase–polymerase chain reaction (RT-PCR) positive hepatocellular carcinoma (HCC) cases and 18 morphologically normal hepatic tissues distant to tumors (MNT) for the correlation between HCV-NS3P, p53, p21waf, mdm2, p21ras and c-erbB2 and DNA content by immunohistochemistry and image analysis. Results: The NS3P expression was lower in HCC (65.6%) than in MNT (94.4%) patients. The expression level of studied genes in HCC was: p53 (56.25%), p21waf (43.7%), mdm2 (59.4%), p21-ras (73.3%) and c-erbB2 (75%). Whereas in MNT, it was 22.2, 61.1, 44.4, 41.2 and 77.8%, respectively. The NS3P expression showed a significant correlation with the presence of cirrhosis, chronic active hepatitis (CAH) and tumor grade (P

Hepatitis C virus genotypes and subtypes determination is an important factor for understanding the epidemiology of the virus, in the pre-treatment evaluation of the patients and in defining better treatment strategies. In the present study, we compared two commercially available assays for HCV genotyping: the reverse hybridization based Innogenetics INNO-LiPA HCV II and the direct sequencing by TRUGENE assay. The study included 31 HCV-RNA positive Egyptian patients; 18 patients with chronic active hepatitis, 8 with HCC, and 5 with cirrhosis. Using the TRUGENE genotyping test, all the samples had genotype 4 (100%) and subtyped as 4a in 18/31(58%), 4c in 10/31 (32%), 4e in 1/31 (3%), 4a/c in 1/31 (3%), and 4g in 1/31 (3%). Using the INNO-LiPA assay, 30 samples had genotype 4 (97%), and 1 sample had genotype 1e (3%). One sample showed mixed infection with type 4f and type 1. Only six samples were subtypable by INNO-LiPA, three were genotype 4c/d, and the other three were 4f, 4e, and 1e. Seven samples gave reactivity in the INNO-LiPA of lines 5, 6, 16, 17, 18, which are considered untypable by the interpretation chart but considered to be a rare HCV genotype 4 by the manufacturer. At the genotype level, there was a 97% concordance between TRUGENE sequencing and INNO-LiPA, but at the subtype level the concordance rate was 3% only. We conclude that the TRUGENE genotyping assay is a reliable test for HCV genotyping for the detection of major types and subtypes detection, while INNO-LiPA is a good test at the genotype level but unreliable for subtyping especially in the Egyptian population. This is mainly due to the high diversity of genotype 4, which is the most prevalent genotype in Egypt.

We have investigated the familial aggregation of colorectal cancer and hereditary nonpolyposis colorectal cancer (HNPCC) in Egypt because of the high incidence of colorectal cancer in Egyptian children and young adults and the prevalence of consanguinity there. In a pilot study, we conducted detailed interviews with 111 Egyptian colorectal cancer patients and 111 healthy Egyptian controls about their family histories of colorectal cancer, and other cancers, consanguinity, age at diagnosis, symptoms and recurrence. Eight patients (7.2%) had one or more first- or second-degree relatives under age 40 with colorectal cancer, suggestive of HNPCC by the Amsterdam criteria. One of these families had a typical history of HNPCC, with 4 relatives having colorectal cancer in 3 generations; 3 of these relatives were younger than age 45 at colon cancer diagnosis, and other relatives had extracolonic tumors. Another 14 patients (12.6%) had a first- or second-degree relative with a family history of other neoplasms such as endometrial, urinary and hepatobiliary cancers that could also be related to HNPCC. Four patients with early-onset colon cancer and a family history of other HNPCC-related cancers reported that their parents were first-degree cousins. Int. J. Cancer 77:811–816, 1998.© 1998 Wiley-Liss, Inc.

The valence of Pr with increasing Pr concentration in the Y 1-x Pr x Ba 2 Cu 3 O 7-δ system is investigated by measuring the Cu 2p, Pr 3d, Ba 3d, and O 1s photoemission spectra for different Pr concentrations (x = 0 to 1.0) and the related Pr oxide (Pr 6 O 11 ). The Pr 3d spectra show that Pr exists in a mixed valence state. The possible presence of Pr at some Ba sites and its consequence is also discussed.

The increasing prevalence of antibiotic-resistant bacteria is creating a real challenge for health care systems worldwide, making the development of novel antibiotics a necessity. In addition to the development of new antibiotics, there is an urgent need for in-depth characterization of the mechanisms of bacterial resistance toward new drugs. Here, we used essential oils extracted in our laboratory from Piper cubeba against methicillin-resistant Staphylococcus aureus ATCC 43300, one of the most prominent antibiotic-resistant bacteria. Effects of the essential oils extracted from P cubeba on bacteria were mainly evaluated using 2 powerful microscopy techniques: atomic force microscopy and transmission electron microscopy. High-resolution atomic force microscopy images of the cells were obtained close to their native environment by immobilizing the cells on porous Polyether sulfone membranes, which were prepared in our laboratory with a wide range and distribution of pore sizes and depth. Inhibition zones (mm) and minimum inhibitory concentrations were determined. Two different concentrations of the oil were used to treat the cells: 50 μg/mL minimum inhibitory concentration and 25 μg/mL. The 50 μg/mL oil solution caused severe damage to the bacterial cells at microscopic levels while the 25 μg/mL solution showed no effects compared to the control. However, at nanoscopic levels, the 25 μg/mL oil solution caused significant changes in the cell wall, which could potentially impair bacterial activities. These results were also confirmed by transmission electron microscopy micrographs. Our results indicate that the extract has a good biological activity against methicillin- and oxacillin-resistant S aureus and that it acts on the cell wall and plasma (cytoplasmic) membrane.

Medical Physics in Africa has evolved over the last half a century from the Republic of South Africa in the southern tip of the continent to Ghana and Nigeria in the Western half and also Kenya, Uganda and United Republic of Tanzania in the Eastern sphere of the region and unto Algeria, Egypt, Morocco and Sudan in the Northern part. There is a wide disparity in terms of educational infrastructure and availability of equipment across this very wide geographical landscape to provide the required medical physics services particularly in the health establishments as well as the other areas where the expertise of this cadre of professionals are needed. In terms of human resources capability, the continent can only boast of a slightly more than 300 personnel employed in and around her health facilities and about 60% of these staff are domiciled in just three countries — Egypt, Morocco and Republic of South Africa. An attempt will be made in this paper to discuss the clinical medical physics issues both from the historical perspectives as well as the current state of affairs in the continent which culminated in the recent birth of the Federation of African Medical Physics Organisation (FAMPO) which has just been recently given a charter as the youngest regional body of the International Organisation of Medical Physics (IOMP). Learning Objectives: 1. The Medical Physics infrastructure in terms of equipment and manpower. 2. The Status of Education and Training in Africa. 3. The gaps in the Medical Physics profession that FAMPO intends to address in the continent.

Cation fixation is of great importance to agricultural productivity and to the chemical and physical properties of soils. Reduction of Fe(III) to Fe(II) in clay minerals is known to enhance the potential for K⁺ fixation on drying, but further studies are needed to determine whether K⁺ fixation also increased when reduction occurs without drying, and to measure the potential for fixation of other cations. The objective of this study was to address these questions. The effect of Fe oxidation state on cation fixation was determined by chemically reducing aqueous suspensions of a ferruginous smectite and a montmorillonite with Na₂S₂O₄, then saturating the exchange complex with either K⁺, Ca²⁺, Cu²⁺, or Zn²⁺ using inert-atmosphere techniques. The amount of fixed cation was calculated as the difference between the total and the exchangeable (relative to Mg²⁺) amounts. Both smectites displayed substantial capacity to fix interlayer cations (without drying) as the level of Fe(II) increased in their structures, depending on the cation and the Fe(II) content. For a given Fe(II) content, the amount of cation fixation increased in the order Cu²⁺ < Zn²⁺ < Ca²⁺ < K⁺, which follows precisely the inverse of the hydration energies (ΔHₕyd) of the cations and suggests that reduction of octahedral Fe encourages dehydration of the interlayer region. In both clays, the amount of exchangeable K⁺ was largely independent of Fe(II) content, but virtually all additional negative charge due to Fe reduction was reflected in the nonexchangeable K⁺ fraction. Contribution from the Dep. of Agronomy, Univ. of Illinois.