Improvement of Dielectric, Magnetic and Thermal Properties of OPEFB Fibre⁻Polycaprolactone Composite by Adding Ni⁻Zn Ferrite.

The dielectric and magnetic behaviour and thermal properties of composites based on nickel⁻zinc ferrite (NZF) filler can be improved by the addition of various types of materials. Amongst others, ferrite⁻polymer composites have been subjected to a wide range of research, due to their extensive applications: electromagnetic interference shielding, microwave absorption, electrodes and sensors. Currently, the interest in scientific and technical searches for the potential outcomes of ferrite⁻polymer materials due to their different uses in applications such as telecommunication applications, microwave devices and electromagnetic interference shielding has been growing stronger. The dielectric and magnetic behaviour and thermal properties for such composite materials depend on size, shape and the amount of filler addition. Nickel⁻zinc ferrite material was prepared using the conventional solid-state reaction technique. This study highlights the development of microwave-absorbing material from NZF by adding natural fibres, Oil Palm Empty Fruit Bunch (OPEFB) and polycaprolactone (PCL). OPEFB is considered in this study because it is a solid waste product of the oil palm milling process which is widely and cheaply available. The use of OPEFB in this product may save the environment from oil palm solid waste. A Thermal Hake blending machine was used in blending the powder structure of NZF + OPEFB + PCL, which made it homogeneous. These composites were characterized by the use of Fourier transform infrared (FTIR) spectrometry and scanning electron microscopy (SEM). The thermal degradation behaviour of the composites was analyzed using thermogravimetric analysis (TGA) and differential thermogravimetric (DTG) thermograms. The effective permittivity and effective permeability was obtained over a broad frequency range from 8 to 12 GHz at room temperature. It was observed that the values of effective permittivity and permeability increased as the content of NZF content increased. A rectangular waveguide connected to a microwave vector network analyser (PNA) (HP/Agilent model PNA E8364B) was employed in measuring the reflection coefficient S11 and transmission coefficient S21 parameters of composites for different percentages of NZF filler. This parameter was then used in calculating the microwave absorbing properties (dB).

Characterization of wound infections among patients injured during the 2011 Libyan conflict.

Few studies have analysed the bacterial pathogenesis of infections associated with war-wound in the Eastern Mediterranean region. We analysed surgical wound infections of 1200 patients injured during the Libyan conflict in 2011 and admitted to the emergency services at Tripoli medical centre. Culture swabs or surgical wound debridement samples were collected and cultures were identified and tested for antimicrobial resistance. Of the 1200 patients studied, 498 (42%) were infected with at least 1 pathogen and 57 with >2 pathogens. The most common species were Acinetobacter spp. (isolated from 144 patients), coagulase-negative staphylococci (122), Escherichia coli (107), Pseudomnonas aeruginosa (92) and Klebsiella spp. (86). A high level of resistance to the antibiotics tested was found, especially among Acinetobacter spp. Multi-drug-resistant Gram-negative bacilli were an important complicating factor in wound infections associated with war injuries among injured patients in Libya. Effective policies are needed to control and treat such infections particularly in trauma and emergency services.

Prevalence of hepatitis B and C virus infections and their related risk factors in Libya: a national seroepidemiological survey.

A high prevalence of hepatitis B (HBV) and C virus (HCV) infections has been reported among specific patient groups in Libya; a survey was thus designed to determine the extent of the problem at the national level. A multi-stage sampling design covering all administrative areas of Libya was applied, covering > 65,000 individuals of all age groups. All subjects gave a blood sample and completed a questionnaire on demographic and risk behaviour data. The prevalence of HBV surface antigen (HBsAg) and anti-HCV were 2.2% and 1.3% respectively. The prevalence of anti-HCV increased with age, rising gradually after age 30 years, in contrast to a stable prevalence of HBsAg in all age groups 10+ years. Age-adjusted risk factors for HCV infection were previous hospitalization, surgical operations, previous blood transfusions and intravenous drug use; for HBV infection only family exposure or contact with HBV case were identified.

Prevalence of hepatitis B and C virus infections and their related risk factors in Libya: a national seroepidemiological survey

A high prevalence of hepatitis B [HBV] and C virus [HCV] infections has been reported among specific patient groups in Libya; a survey was thus designed to determine the extent of the problem at the national level. A multi-stage sampling design covering all administrative areas of Libya was applied, covering > 65 000 individuals of all age groups. All subjects gave a blood sample and completed a questionnaire on demographic and risk behaviour data. The prevalence of HBV surface antigen [HBsAg] and anti-HCV were 2.2% and 1.3% respectively. The prevalence of anti-HCV increased with age, rising gradually after age 30 years, in contrast to a stable prevalence of HBsAg in all age groups 10+ years. Age-adjusted risk factors for HCV infection were previous hospitalization, surgical operations, previous blood transfusions and intravenous drug use; for HBV infection only family exposure or contact with HBV case were identified

Characterization of wound infections among patients injured during the 2011 Libyan conflict

Few studies have analysed the bacterial pathogenesis of infections associated with war-wound in the Eastern Mediterranean region. We analysed surgical wound infections of 1200 patients injured during the Libyan conflict in 2011 and admitted to the emergency services at Tripoli medical centre. Culture swabs or surgical wound debridement samples were collected and cultures were identified and tested for antimicrobial resistance. Of the 1200 patients studied, 498 [42%] were infected with at least 1 pathogen and 57 with > 2 pathogens. The most common species were Acinetobacter spp, [isolated from 144 patients], coagulase-negative staphylococci [122], Escherichia coli [107], Pseudomonas aeruginosa [92] and Klebsiella spp. [86]. A high level of resistance to the antibiotics tested was found, especially among Acinetobacter spp. Multi-drug-resistant Gram-negative bacilli were an important complicating factor in wound infections associated with war injuries among injured patients in Libya. Effective policies are needed to control and treat such infections particularly in trauma and emergency services

Management of major blunt pediatric renal trauma: single-center experience.

OBJECTIVE: To review the impact of major pediatric renal trauma and its management on long-term function and morphology of the injured kidney. METHODS: Thirty-six blunt trauma patients (20 males, 16 females) presented in 2004-2007 (age range 2 days to 14 years; mean 6.2 years). Thirty-seven renal units were included: 13 grade III, 14 grade IV, and 10 grade V injuries. Follow up was for 3-38 (mean 14) months. Patients were managed non-operatively unless vitally unstable. The most common causes of trauma were motor vehicle accidents and falls. Fourteen patients had associated non-renal injuries. Four patients had pre-existing renal problems. RESULTS: The surgical intervention group (13 patients, 36%) included 9/10 grade V and 4/14 grade IV renal injuries. Surgical repair of lacerations was performed in seven cases, partial nephrectomy in four cases and nephrectomy in two cases. Follow up showed no significant change in renal function, and none developed hypertension. The non-operative group (24 patients, 63.2%) included all grade III injuries, 10 grade IV injuries, and one grade V injury. There was an excellent outcome for 18/24 patients (75%) with kidney preservation, no complications from urinary extravasation and hematoma resolution. The remaining patients had lower polar infarction (1), renal atrophy (1), persistent subcapsular collection (2), recurrent hematuria requiring angioembolization (1), and there was one death related to central nervous system injury. CONCLUSION: The outcome of our management of pediatric major renal trauma was favorable overall. Longer follow up is needed with regard to renal function and development of hypertension.

Outcome of complete primary bladder exstrophy repair: single-center experience.

OBJECTIVE: Reconstruction of bladder exstrophy remains a challenge. We evaluated our experience with complete primary repair in classic bladder exstrophy. METHODS: A retrospective data review was conducted of bladder exstrophy patients presenting at our institution between May 2000 and September 2007. Fifty-one patients (21 females and 30 males) with classic bladder exstrophy were included. Age of presentation ranged from 24h to 14 months. Mean follow up was 3 years (1 month-7 years). Patients were evaluated for continence, upper tract dilatation and cosmetic result. RESULTS: Eight patients (15.6%) had failed closures and six (11.7%) had fistulae. Evaluation of continence excluded 16 patients not followed up at our center. Thirty-seven percent were continent on clean intermittent catheterization after the age of 5 years. Patients became dry only after augmentation cystoplasty. Upper tract changes were mild during our study with all patients having normal serum creatinine. CONCLUSION: Patients may require more than one procedure for reconstruction. In our series, augmentation was required to achieve acceptable dryness. Early promising results with dry intervals in young patients did not translate to continence in older patients.

Silicon optical fiber.

Described herein are initial experimental details and properties of a silicon core, silica glass-clad optical fiber fabricated using conventional optical fiber draw methods. Such semiconductor core fibers have potential to greatly influence the fields of nonlinear fiber optics, infrared and THz power delivery. More specifically, x-ray diffraction and Raman spectroscopy showed the core to be highly crystalline silicon. The measured propagation losses were 4.3 dB/m at 2.936 microm, which likely are caused by either microcracks in the core arising from the large thermal expansion mismatch with the cladding or to SiO(2) precipitates formed from oxygen dissolved in the silicon melt. Suggestions for enhancing the performance of these semiconductor core fibers are provided. Here we show that lengths of an optical fiber containing a highly crystalline semiconducting core can be produced using scalable fiber fabrication techniques.

Tubeless percutaneous nephrolithotomy in children.

OBJECTIVE: To assess the effectiveness of tubeless percutaneous nephrolithotomy (PCNL) as an alternative to extracorporeal shock-wave lithotripsy (ESWL) in the management of urolithiasis in children. MATERIALS AND METHODS: In 2003-2005 we operated on 20 cases that met the inclusion criteria. Extensive follow-up tests were performed in all patients; stone clearance was defined as the absence of residual fragments on plain abdominal X-ray and renal ultrasound. Pain-scale ruler (0-10) was used to evaluate pain postoperatively. Comparison was made with a group of 10 patients with very similar criteria operated upon with PCN tube. RESULTS: Mean follow-up period was 9 months (3-18 months) and mean age 7.5 years (4-15 years). Mean operative time was 115 min (45-180) with no significant bleeding intra- or postoperatively. Conversion to open surgery was necessary in one case. There were no major perioperative complications. In the tubeless group the pain score was 3-6 (mean 4.6), there was no need for IV analgesia, and median hospital stay was 1.7 days (1-4 days); urine leakage occurred in one patient. In the group with PCN tube the pain score was 5-8 (mean 5.5), IV analgesia was mandatory in four patients, and median hospital stay was 2.8 days (3-4 days); urine leakage occurred in five patients and a small residual stone was detected in one child. CONCLUSION: Tubeless PCNL in children has the advantages of being less painful, less troublesome and shortening the hospital stay of the child. The decision to use this procedure is best made intraoperatively and depends on the experience of the surgeon.

Artesunate plus sulfadoxine-pyrimethamine in the treatment of uncomplicated Plasmodium falciparum malaria during pregnancy in eastern Sudan.

Malaria during pregnancy is associated with serious adverse effects; these could be avoided with effective treatment. Artesunate plus sulfadoxine-pyrimethamine (AS+SP) is a promising antimalarial combination; however, few data are available on its safety during pregnancy. The present study was carried out in New Halfa Hospital, eastern Sudan, between September 2004 and March 2005. Thirty-two pregnant Sudanese women with uncomplicated Plasmodium falciparum malaria were treated with AS+SP at a mean of 29.7 weeks of gestation. The patients were followed-up until delivery and the babies were followed-up until the age of 1 month. The drug was well tolerated, the parasitaemia was cleared and the patients were symptom-free within 2 days. All the patients delivered full-term live babies. One of the babies died on the fourth day; none of the women died and there was no miscarriage, stillbirth, or congenital abnormalities in the newborn babies. Thus, this small descriptive study failed to detect unintended effects of AS+SP during pregnancy.

Manifestations of falciparum malaria in pregnant women of Eastern Sudan.

OBJECTIVE: This study was conducted to investigate the morbidity pattern of malaria during pregnancy in New Halfa Teaching Hospital, Eastern Sudan, where malaria transmission is unstable. METHODS: Pregnant (or in the puerperium) women presented with symptoms of falciparum malaria to the hospital during the period of November 2002 to March 2003 were enrolled to the study. Their socio-demographic characters, physical examinations, especially manifestations of severe falciparum malaria were performed and data were recorded. Blood films for malaria, urine, hemoglobin and blood glucose were tested. RESULTS: Fifty-nine pregnant (or in the puerperium) women with falciparum malaria were presented in this study. The mean +/- SD gravidity was 3.3 +/- 2.1. Fourteen (23.7%) out of 59 patients presented with one or more manifestations of severe malaria according to the World Health Organization criteria. Severe anemia (5), pulmonary edema (4), jaundice (3), hypoglycemia (3) and hypotension (1) were the manifestations of the severe illness. In comparison to non-severe group, patients with severe illness have significantly higher temperature and significantly lower hemoglobin level. The other parameters were not significantly different between the 2 groups of patients. In the severe cases, one patient was presented with missed second trimester abortion and the 6/59 (10.2%) patients delivered prematurely 4 were in the severe form. There were 4 perinatal deaths all in the severe group and there was one maternal death due to pulmonary edema. CONCLUSION: In this locality not only primigravidae but all parities were infected with falciparum malaria and different manifestations of severity were detected. Higher perinatal mortalities were documented.

Antibiotic resistance: prospects for the new millennium.

Antibiotic resistance, which has been recognized to be an important clinical problem, varies in prevalence from one country to another and among the pathogens themselves. This has great clinical, economic, political and environmental implications worldwide. Strict adherence to the ongoing measures of infection control, education and antibiotic policy does minimize antibiotic resistance. The limits surrounding such approaches make consideration of new strategies become inevitable. These may include the use of new therapeutic modalities, probiotics, prebiotics and the cationic peptides. Multidisciplinary action by governments, drug industry, academicians and legislators should also be considered to overcome such a global problem. It is better that we try to prevent antibiotic resistance, rather than having to deal with it once it occurs. It is hoped that the present review will provide useful data on antibiotic resistance and assist in making rational choices to overcome this emerging problem.

PDZ proteins interacting with C-terminal GluR2/3 are involved in a PKC-dependent regulation of AMPA receptors at hippocampal synapses.

We investigated the role of PDZ proteins (GRIP, ABP, and PICK1) interacting with the C-terminal GluR2 by infusing a ct-GluR2 peptide ("pep2-SVKI") into CA1 pyramidal neurons in hippocampal slices using whole-cell recordings. Pep2-SVKI, but not a control or PICK1 selective peptide, caused AMPAR-mediated EPSC amplitude to increase in approximately one-third of control neurons and in most neurons following the prior induction of LTD. Pep2-SVKI also blocked LTD; however, this occurred in all neurons. A PKC inhibitor prevented these effects of pep2-SVKI on synaptic transmission and LTD. We propose a model in which the maintenance of LTD involves the binding of AMPARs to PDZ proteins to prevent their reinsertion. We also present evidence that PKC regulates AMPAR reinsertion during dedepression.

Seroepidemiology of hepatitis B virus markers among hospital health care workers. Analysis of certain potential risk factors.

OBJECTIVES: To determine, the prevalence of hepatitis B virus markers among hospital health care workers, to determine the influence of some risk factors on such prevalence and to outline the specific policies to tackle such problems among hospital health care workers. METHODS: Hepatitis B virus markers including hepatitis B surface antigen, anti-hepatitis B surface antigen and anti-hepatitis B core antigen were determined from sera samples collected from 459 hospital health care workers at different hospital departments. The prevalence of hepatitis B virus among these employees was correlated by a variety of risk factors such as gender, age, blood transfusion, and needle-stick and sharps injuries, and previous history of jaundice using logistic regression analyses. RESULTS: Of the hospital health care workers studied 143 (31%) of employees showed evidence of previous hepatitis B virus infection, including 17 (4%) carriers. The highest incidence was among those who were working at infectious diseases departments where 22 (43%) employees were found to be seropositive, followed by 26 (41%) employees from surgical departments. The risk factors, which were found to influence seropositivity, include age over 40 years old, needle-stick and sharps injuries and previous blood transfusion. Other factors such as gender, and previous history of jaundice were statistically insignificant. CONCLUSION: The hepatitis B virus infection was high among the hospital health care workers studied. This was influenced by certain potential occupational risk factors. As there is emerging evidence that vaccination among health care workers was infective. Specific measures should be implemented to reduce such risk. These may include strict policies on sharps and considering any blood or other body fluids being a potential risk. Education, clinical advice and health insurance should be available for health care workers who are at a higher risk of contracting hepatitis B virus infection.

Clinical and epidemiological features of pseudomonas aeruginosa infections at the Libyan Hospitals.

Full text is available as a scanned copy of the original print version.

New features in the Saudi Medical Journal.

Full text is available as a scanned copy of the original print version.

Bacteriocins: nature, function and structure.

Bacteriocins are extracellular substances produced by different types of bacteria, including both Gram positive and Gram negative species. They can be produced spontaneously or induced by certain chemicals such as mitomycin C. They are biologically one of the important substances, and have been found to be useful in membrane studies and also in typing pathogenic microorganisms causing serious nosocomial infections. Bacteriocins are a heterogeneous group of particles with different morphological and biochemical entities. They range from a simple protein to a high molecular weight complex: the active moiety of each molecule in all cases seems to be protein in nature. The genetic determinants of most of the bacteriocins are located on the plasmids, apart from few which are chromosomally encoded. These bactericidal particles are species specific. They exert their lethal activity through adsorption to specific receptors located on the external surface of sensitive bacteria, followed by metabolic, biological and morphological changes resulting in the killing of such bacteria. This review summarises the classification, biochemical nature, morphology and mode of action of bacteriocins as well as their genetic determinants and the microbiological relevance of these bactericidal agents.

Urinary beta-HCG in benign and malignant urinary tract diseases.

Detectable levels of HCG have been reported in conditions other than normal pregnancy, including threatened abortion, ectopic pregnancy, trophoblastic tumors, carcinomas of the stomach, liver, pancreas and breast as well as multiple myeloma and melanoma. The present study was conducted to estimate urinary beta-HCG in bladder cancer and benign urinary tract disorders. 163 individuals were included, 68 with bladder cancer (60 males and 8 females), 64 with benign urinary tract diseases (55 males and 9 females) and 31 normal healthy controls (26 males and 5 females). Urinary beta-HCG was estimated by the ELISA technique using the reagents supplied by DRG International Inc., Germany. Results of the study revealed an overexpression of beta-HCG in malignant and benign urinary tract diseases. 60.3% of the cancer patients and 29.7% of patients with benign diseases showed urinary beta-HCG values above the upper limit of the control group (2mIU/ml).

Prevalence of metronidazole-resistant Helicobacter pylori in dyspeptic patients.

Susceptibility to metronidazole of 213 clinical strains of H. pylori from dyspeptic patients was determined by a plate dilution method. Seventy two (33.8%) of the strains were resistant to metronidazole (MIC > 8 mg/L), 20 of these were from 24 patients who had received previously metronidazole (83.3%), giving a primary (pretreatment) resistance rate of 27.5% (52/189). The resistance rate was higher in women than in men, especially aged 50 to 59 years old (43.6% vs 23.3%, p < 0.001). The resistance rate was lower in patients at 60 or over (9.8%), but similar between the younger patients groups (38.8% - 49.0%). There was no difference in the resistance rate between peptic ulcer disease (32.6%) and nonulcer dyspepsia (34.7%). These data indicated that metronidazole resistance in H. pylori is absolutely associated with previous use of the drug, and the higher resistance rate in women may be due to the more frequent prescription of the drug for their gynaecological infection or operation. Therefore, testing of susceptibility of H. pylori to metronidazole is important. A new susceptibility testing technique, the E-test was evaluated in this study and found to give comparable results to the plate dilution method and also had the advantage of being simple to perform.