Role and Function of KPC and MBL Enzymes in Increasing the Pathogenicity of Pseudomonas Aeruginosa Isolated from Burn Wounds

BACKGROUND AND OBJECTIVE: Pseudomonas aeruginosa is one of the main causes of hospital infections. Pathogenic factors in this bacterium may play a role in the resistance to carbapenem and beta-lactam. The purpose of this study was to evaluate the role and function of KPC and MBL enzymes in increasing the pathogenicity of Pseudomonas aeruginosa isolated from burn wounds. METHODS: In this cross-sectional study, 63 isolates of Pseudomonas aeruginosa from burn wounds of different patients were isolated using biochemical tests such as fermentation of sugars in the OF medium, oxidase test, and so on. Determination of resistance pattern and strains with metallobetalactamase and carbapenema was done by disc diffusion method. The oprD gene was used for molecular confirmation of isolates. PCR method was used to detect pathogenicity genes. FINDINGS: Out of 63 isolates of Pseudomonas aeruginosa isolated from burn patients, 10 isolates (15.83%) had KPC enzyme and 13 isolates (20.63%) had MBL enzymes. Doripenem, Ertapenem and meropenem were the most frequent. Also, the lasB gene was observed in 43 isolates (68.25%), plcN gene in 41 isolates (65.07%), lasA gene in 20 isolates (31.74%), apr in 60 isolates (95.23%), phzI gene in 53 isolates (84.12%), the phzII gene in 38 isolates (60.31%), phzH gene in 30 isolates (47.61%) and plcH gene in 56 isolates (88.88%). CONCLUSION: The results of this study showed that the production of Carbapnemase and MBL enzymes increased the pathogenicity of Pseudomonas aeruginosa isolated from burn wounds

Investigation of the Relationship between the Presence of Chromosomal and Plasmid-Encoded AmpC Genes and Type of Clinical Specimen in Pseudomonas Aeruginosa

BACKGROUND AND OBJECTIVE: Different clinical specimens play a decisive role in the type and nature of drug resistance in pathogenic organisms. Occasionally, the presence of certain antibiotic resistance genes is associated with the type of clinical specimen. The aim of this study was to determine the relationship between the presence of chromosomal and plasmid-encoded AmpC genes and type of clinical specimen in Pseudomonas aeruginosa. METHODS: In this descriptive and experimental study, 114 isolates of Pseudomonas aeruginosa, and clinical specimens including blood, urine, wound secretion, burn injuries were collected from teaching hospitals in Hamadan. The presence of chromosomal and plasmid-encoded AmpC genes was evaluated using multiplex PCR technique. FINDINGS: The plasmid-encoded AmpC genes were observed more than chromosomal genes in Pseudomonas aeruginosa isolates. The FOX gene with a value of 29 (37.66%) (p≤0.037) and DHA gene with a value of 5(6.4%) (p≤0.015) in plasmid-encoded AmpC genes, while FOX gene with a value of 39 (48.75%) (p≤0.001) and MOX gene with a value of 2 (7.36%) in chromosomal AmpC genes had the highest and lowest frequency, respectively. CONCLUSION: The results of the study showed that the presence of chromosomal and plasmid-encoded AmpC genes may have various frequencies according to the type of clinical specimen

Relationship of chemotherapeutic agents with menstrual disorders in nursing staff

BackgroundOccupational contact with chemotherapeutic drugs is considered as a potential threat for health. These agents may cause menstrual disorders according to many studies regarding the effects of long-term contact of the agents with health personnel. Oncology nurses involved in the preparation and administration of these drugs may be prone to many threats and complications. PurposeThis retrospective study was conducted to detect menstrual disorders in nursing staff with or without contact with chemotherapeutic agents at Namazi Hospital in Shiraz. MethodsNurses from chemotherapy, hematology, pediatrics, Eastern 3 as well as bone marrow transplantation wards in case group and from internal general, internal women, internal men as well as Western 3 in control group (totally 94 subjects) was selected. A questionnaire in 4 parts including demographic, past medical history, menstrual disorders and contact with the agents was used for data collection. Pelvic sonography and hormonal tests were also checked. Results61.1% of nurses in the case group suffered from menstrual disorders in comparison with 53.3% of subjects in the control group. TSH, FSH, and LH levels were higher and prolactin level was lower in the case group. Most nurses in the case group experienced the disorders in the last 6 months. No significant relationship was found between menstrual disorders and application of protective devices. ConclusionBecause of potential effects of contact with chemotherapeutic agents on reproductive system, involved staff should use available protective devices to prevent infertility and menstrual disorders. Keywords: Menstrual disorders, Occupational contact, Chemotherapeutic agents.           

Half-sized cylindrical invisibility cloaks using double near zero slabs with realistic material size and properties

A method is introduced to miniaturize invisibility cloaks by 50% using wave tailoring and finite/ non-zero wave impedance of double near zero (DNZ) slabs. Unlike previous works, which use thick dielectric matching layers to miniaturize internal cloaks, the proposed technique is applied to both internal and external cylindrical cloaks using a thin and short DNZ slab to change cloaks' shapes to half-cylinder shells. Moreover, sets of structures are introduced for the half sized cloaks to enable using feasible-to-fabricate structures with the help of a rigorous theoretical analysis, which is validated via full-wave simulations. All of the presented results show that the proposed half cloaks can function perfectly well. The sensitivity of half-sized cloaks to the length and material properties of the DNZ slab is investigated to find the shortest length and the highest values of the permittivity and permeability for the slab to have small yet realizable structures. The analysis shows that slabs with length as small as the diameter of the cloaks and constitutive parameters (permittivity and permeability) as high as epsilon(slab)= mu(slab) = 0.1-0.1 i and epsilon(slab)= mu(slab) = 0.05-0.04i for half-sized external cloaks and half-sized internal cloaks, respectively, can still considerably reduce the scattered fields. The effect of the loss and incident angle of the field on the performance of the miniaturized cloaks are also analyzed. (C) 2017 Optical Society of Americ

The Relationship between Random Urinary Protein-to-Creatinine Ratio and 24-hours Urine Protein in Diagnosis of Proteinuria in Mild Preeclampsia

Background: The purpose of this study was to evaluate whether a random urinary protein / creatinine ratio is a clinically useful predictor of significant proteinuria (300 mg/24 hr) instead of 24- hours urine protein, among women with suspected preeclampsia.
 Methods: Women with suspected preeclampsia and gestational age of 20 weeks were included in a prospective study. Patients with chronic hypertension, diabetes mellitus, or preexisting renal disease were excluded. Protein/ creatinine ratio was obtained before 24-hours urine collection. Positive and negative predictive values and sensitivity and specificity of the protein/creatinine ratio for significant proteinuria (300 mg) were calculated, based on 24-hours urine total protein.
 Results: 100 women were evaluated totally. Mean maternal and gestational ages were 27.3 years and 33.26 weeks, respectively.73% of cases had significant proteinuria based on 24-hours urine collection. Good correlations were found between the protein/creatinine ratio in random urine samples and both the 24-hours urine protein excretion and the 24- hours urine protein/creatinine ratio in patients with mild preeclampsia (r=0.484, P<0.0001, and r=0.345, P<0.0001, respectively) .Receiver operator characteristic (ROC) analysis revealed an area under the curve of 0.944. The best cutoff value was of >0.18 which yields a sensitivity of 86.3%, a specificity of 100%, with a positive predictive value of 100%, and a negative predictive value of 73%.
 Conclusion: The random urinary protein –to- creatinine (P: C) ratio is strongly associated with the 24-hours total protein excretion. A cutoff value of > 0.18 is a good predictor of significant proteinuria .P: C ratio could replace the 24- hours urine collection as a simpler, faster, and more accurate method for the diagnosis of significant proteinuria.
 Key words: Preeclampsia, significant proteinuria, protein / creatinine (P: C) ratio, 24- hours urine total protein leve

Uniqueness Theorem for Lossy Anisotropic Inhomogeneous Structures with Diagonal Material Tensors

The method of transformation optics (TO) was introduced some time ago to create anisotropic inhomogeneous structures like hyper-lenses and invisibility cloaks which have diagonal material tensors. In this paper, we prove that the uniqueness theorem is valid for anisotropic inhomogeneous structures with diagonal constitutive tensors if all the tensor elements of all regions are lossy. The uniqueness theorem says for a particular sets of boundary conditions the solution to Maxwell equations are unique. The uniqueness theorem is proven for three cases: Single medium, media composed of two materials of our interest, and media composed of two materials which the one with diagonal material tensors is surrounded by the other one which could be an isotropic material. The latter case, is the one that can be considered for the TO-based materials like invisibility cloaks or hyper-lenses that have diagonal anisotropic inhomogeneous constitutive parameters. Because, the cloaks or hyper-lenses are usually surrounded by a free space and also the sources are usually outside of them

On the uniqueness of inverse electromagnetic problems for invisibility cloaks

Devices like invisibility cloaks are designed based on the method of transformation optics, which have anisotropic inhomogeneous structures. In this paper, we examine uniqueness of the inverse problem for such structures. We prove all these materials have the same surface field distribution on a surface enclosing the area of interest, while solutions to Maxwell's equations inside them are different. The uniqueness theory suggests that within the surface, the same medium should exactly be present. However, for anisotropic inhomogeneous media of our interest, this paper illustrates that this might not be true, despite the result of a previous study that shows uniqueness could be true for some anisotropic inhomogeneous structures. For the analysis, the transverse electric (TE) Z-polarization is used. The simulation results are obtained by a commercial Finite-Element based simulator

Size reduction of electromagnetic devices using double near zero materials

The phase pattern tailoring and finite/nonzero wave impedance properties of double-near-zero materials, which have both the permittivity and permeability close to zero, are utilized to reduce the size of certain electromagnetic devices. As a proof of concept, it is applied to internal and external cloaks and field concentrators. The proposed technique enables reducing the size of the investigated devices by 50% by changing their structure from a full cylinder to half cylinder. The half-sized devices can still perform the functions of their full-size counterparts. To understand the phenomenon and validate the numerical results, the method is proven analytically for the internal cloak. The same analysis can also be applied for the external cloak and concentrator. For the included analysis, the transverse electric Z-polarization is used. For the transverse magnetic Z-polarization, the duality principal can be applied