Role of Class I, II and III Integrons in Multidrug Resistance in Pseudomonas aeruginosa Isolated from Nosocomial Hospital

Abstract Aims: The increasing usage of antibiotics can cause resistance to the treatment of infections, which can caused by bacteria, e.g. Pseudomonas aeruginosa. The aim of this study was to trace the class I, II and III integrons in isolates of P. aeruginosa of nosocomial infection and determining the antibiotic resistance pattern of the bacteria. Instrument & Methods: In this cross-sectional study, 100 Pseudomonas aeruginosa clinical isolates of infected wounds, bedsores, burns, urinary tract infections and respiratory tract infections were collected from patients of 3 Isfahan City hospitals, Iran (Al Zahra, Kashani, Shariati) in 2015. After identification tests and antibiogram, integrons class I, II and III were detected by M-PCR method. Data analysis were performed in SPSS 16 software using Chi-square and Fisher exact tests and the relationship between the presence of class III, II, I was calculated by M-PCR test. Findings: All isolates had multiple antibiotic resistances. The highest antibiotic resistance was to Tetracycline (85) and the lowest to Norfloxacin (12.5). There were significant differences between class I and the two other classes of integrons (p=0.036). There was a statistically significant difference between the presence of blaTEM gene in Pseudomonas aeruginosa with other coding genes for antibiotic resistance (p=0.029). Conclusion: Pseudomonas aeruginosa isolates are multi-drug resistant and almost all isolates from clinical infections have class I, II and III Integrons

The Enzymatic Activity and Molecular Characterization of a Secreted Subtilisin-Like Protease in Microsporum gypseum and Trichophyton vanbreuseghemii

Background: Subtilisin -like proteases are the group of proteases including keratinases found in dermatophytes which de­graded keratin. Determination of the proteases activity of Trichophyton vanbreuseghemii isolates which were obtained from soil and clinical and soil isolates of Microsporum gypseum in Iran and characterization of their genome were aim of present study.Methods: Ezymatic activity was determined by use of chromogenic substrates. The genes, which coded subtilisin-like pro­teases in above-mentioned dermatophytes, was identified and amplified by using specific primers in PCR. Results: The highest yield of enzyme production was observed in only one isolate of T. vanbreuseghemii Ir-84 whereas low enzyme activity was observed in M. gypseum isolates. Homology study of obtained nucleotide as well as amino acid sequences indicated different rates of homology with other subtilisin-like proteases genes in other pathogenic dermato­phytes. Conclusion: Intra-strain differences were observed in production of serine proteinases and molecular characterization of genes encoding such enzymes could be of great interest for studies on pathogenicity and other purposes

Probing the low-energy electron-scattering dynamics in liquids with high-harmonic spectroscopy

High-harmonic spectroscopy (HHS) is a nonlinear all-optical technique with inherent attosecond temporal resolution, which has been applied successfully to a broad variety of systems in the gas phase and solid state. Here, we extend HHS to the liquid phase, and uncover the mechanism of high-harmonic generation (HHG) for this phase of matter. Studying HHG over a broad range of wavelengths and intensities, we show that the cut-off (Ec) is independent of the wavelength beyond a threshold intensity, and find that Ec is a characteristic property of the studied liquid. We explain these observations within an intuitive semi-classical model based on electron trajectories that are limited by scattering to a characteristic length, which is connected to the electron mean-free path. Our model is validated against rigorous multi-electron time-dependent density-functional theory calculations in, both, supercells of liquid water with periodic boundary conditions, and large clusters of a variety of liquids. These simulations confirm our interpretation and thereby clarify the mechanism of HHG in liquids. Our results demonstrate a new, all-optical access to effective mean-free paths of slow electrons (≤10 eV) in liquids, in a regime that is inaccessible to accurate calculations, but is critical for the understanding of radiation damage to living tissue. Our work also establishes the possibility of resolving sub-femtosecond electron dynamics in liquids, which offers a novel, all-optical approach to attosecond spectroscopy of chemical processes in their native liquid environment

Biology and population dynamics of Scaeva albomaculata (Diptera: Syrphidae) in almond orchards of Shahrekord, Iran

Biology of Scaeva albomaculata (Macquart) was investigated on Brachycaudus amygdalinus (Schouteden) as a prey in laboratory conditions (20 ± 2 ºC and 45 ± 5 % RH). Developmental times were 2.57 ± 0.098, 1.57 ± 0.072 and 4.3 ± 0.085 days for the first, second and third instar larvae, respectively. The first and second instar larvae of syrphid fly consumed 21.7 ± 0.87 and 35.1 ± 1.25 the first and second nymphs, respectively, whereas the third instar larvae consumed 613.2 ± 18.43 alate nymphs of B. amygdalinus. Adults of syrphid flies mostly emerged in early morning. Population dynamics of eggs and larvae and larval behavior were studied from emergence time (early March) to late October during 2001-2004 in two regions (Shahrekord and Shorab-Saghir). In natural conditions, the larvae that completed their growth left the almond twigs and pupated at a depth of 3-5 cm below the soil surface. The most important natural enemies of S. albomaculata larvae were identified as Diplazon laetatorius (Fabricius) (Hym.: Ichneomonidae) and Dotriothorax sp. (Hym.: Encyrtidae), which parasitized 34% and 5% of the larvae, respectively. These parasitoids emerged from pupae of S. albomaculata. Another mortality agent was an unknown pathogen, which caused the body content of the pupae to become a milky liquid

Blueberry muffin rash in a patient with hemolytic disease of the newborn due to anti-Cw

Blueberry muffin rash is a characteristic multiple bluish skin nodules associated with perinatal infection, severe and chronic anemia, and neoplastic infiltrative diseases. We present an unusually severe case of hemolytic disease of the newborn. He required exchange transfusions for several times. The complete work up led to the diagnosis of anti-Cw. The skin lesion regressed spontaneously within one month

Probability and consequences of a rapid boron dilution sequence in a PWR

The reactor restart scenario is one of several beyond-design-basis events in a pressurized water reactor (PWR) which can lead to rapid boron dilution in the core. This in turn can lead to a power excursion and the potential for fuel damage. A probabilistic analysis had been done for this event for a European PWR. The estimated core damage frequency was found to be high partially because of a high frequency for a LOOP and assumptions regarding operator actions. As a result, a program of analysis and experiment was initiated and corrective actions were taken. A system was installed so that the suction of the charging pumps would switch to the highly borated refueling water storage tank (RWST) when there was a trip of the RCPs. This was felt to reduce the estimated core damage frequency to an acceptable level. In the US, this original study prompted the Nuclear Regulatory Commission to issue an information notice to follow work being done in this area and to initiate studies such as the work at BNL reported herein. In order to see if the core damage frequency might be as high in US plants, a probabilistic assessment of this scenario was done for three plants. Two important conservative assumptions in this analysis were that (1) the mixing of the injectant was insignificant and (2) fuel damage occurs when the slug passes through the core. In order to study the first assumption, analysis was carried out for two of the plants using a mixing model. The second assumption was studied by calculating the neutronic response of the core to a slug of deborated water for one of the plants. All three types of analyses are summarized below. More information is available in the original report

Reassessment of selected factors affecting siting of Nuclear Power Plants

Brookhaven National Laboratory has performed a series of probabilistic consequence assessment calculations for nuclear reactor siting. This study takes into account recent insights into severe accident source terms and examines consequences in a risk based format consistent with the quantitative health objectives (QHOs) of the NRC`s Safety Goal Policy. Simplified severe accident source terms developed in this study are based on the risk insights of NUREG-1150. The results of the study indicate that both the quantity of radioactivity released in a severe accident as well as the likelihood of a release are lower than those predicted in earlier studies. The accident risks using the simplified source terms are examined at a series of generic plant sites, that vary in population distribution, meteorological conditions, and exclusion area boundary distances. Sensitivity calculations are performed to evaluate the effects of emergency protective action assumptions on the risk of prompt fatality and latent cancers fatality, and population relocation. The study finds that based on the new source terms the prompt and latent fatality risks at all generic sites meet the QHOs of the NRC`s Safety Goal Policy by margins ranging from one to more than three orders of magnitude. 4 refs., 17 figs., 24 tabs

STAT3-mediated apoptotic-enhancing function of sclareol against breast cancer cells and cell sensitization to cyclophosphamide

Sclareol is an organic compound with potential anti-tumor effects against various cancer types. However, its precise molecular mechanism in the suppression of tumor growth has not been fully elucidated. In the present study, the anti-proliferative and apoptosis-inducing effects of sclareol with cyclophosphamide were investigated in breast cancer cells and the involvement of the JAK/ STAT pathway was evaluated. For this purpose, MCF-7 breast cancer cells were cultured and treated with various concentrations of sclareol to determine its IC50. Cell viability was measured by MTT assay and apoptosis was assessed by flow cytometric analysis of annexin V binding. Gene and protein expression were examined by real-time PCR and Western blotting, respectively. The activity of caspase enzymes was also measured. The results showed that sclareol significantly reduced cell viability and triggered cell death and its co-administration with cyclophosphamide enhanced its anti-cancer properties. Additionally, sclareol up-regulated the expression of p53 and BAX and reduced the expression of Bcl-2. Docking studies indicated an interaction between sclareol and STAT3 which was proved by attenuation of STAT3 phosphorylation after treatment of the cells with sclareol. Sclareol was also capable of suppressing the function of IL-6 in modulating the expression of apoptosis-associated genes. Altogether these data suggest the potential of sclareol as an anti-cancer agent and demonstrate that a combination of sclareol with cyclophosphamide might serve as an effective chemotherapeutic approach resulting in improvements in the treatment of breast cancer. © 2020, Iranian Journal of Pharmaceutical Research. All rights reserved

Uncertainties in source term estimates for a station blackout accident in a BWR with Mark I containment

In this paper, attention is limited to a single accident progression sequence, namly a station blackout accident in a BWR with a Mark I containment building. Identified as an important accident in the draft version of NUREG-1150 a station blackout involves loss of both off-site power and dc power resulting in failure of the diesels to start and in the unavailability of the high pressure injection and core isolation cooling systems. This paper illustrates the calculated uncertainties (Probability Density Functions) associated with the radiological releases into the environment for the nine fission product groups at 10 hours following the initiation of core-concrete interactions. Also shown are the results ofthe STCP base case simulation. 5 refs., 1 fig., 1 tab

Evaluation of probabilistic photometric redshift estimation approaches for the Rubin Observatory Legacy Survey of Space and Time (LSST)

Many scientific investigations of photometric galaxy surveys require redshift estimates, whose uncertainty properties are best encapsulated by photometric redshift (photo-z) posterior probability density functions (PDFs). A plethora of photo-z PDF estimation methodologies abound, producing discrepant results with no consensus on a preferred approach. We present the results of a comprehensive experiment comparing 12 photo-z algorithms applied to mock data produced for The Rubin Observatory Legacy Survey of Space and Time Dark Energy Science Collaboration. By supplying perfect prior information, in the form of the complete template library and a representative training set as inputs to each code, we demonstrate the impact of the assumptions underlying each technique on the output photo-z PDFs. In the absence of a notion of true, unbiased photo-z PDFs, we evaluate and interpret multiple metrics of the ensemble properties of the derived photo-z PDFs as well as traditional reductions to photo-z point estimates. We report systematic biases and overall over/underbreadth of the photo-z PDFs of many popular codes, which may indicate avenues for improvement in the algorithms or implementations. Furthermore, we raise attention to the limitations of established metrics for assessing photo-z PDF accuracy; though we identify the conditional density estimate loss as a promising metric of photo-z PDF performance in the case where true redshifts are available but true photo-z PDFs are not, we emphasize the need for science-specific performance metrics