Occurrence of crown gall disease on Ficus benjamina in Fars and Isfahan provinces of Iran

Ficus benjamina, commonly known as weeping fig, Benjamin’s fig or Ficus tree is a species of flowering plant in the family of Moraceae. It is native to south and south-east Asia and Australia. Crown gall tumours were collected from branches of one-year-old weeping fig (F. benjamina L.) trees. A total of 50 strains of Agrobacterium tumefaciens were isolated from diseased Ficus plants and their morphological, molecular and biochemical characteristics were studied; pathogenicity tests on tomato, F. benjamina and Bryophyllum daigremontianum were also conducted. Based on the biochemical characteristics, pathogenicity test and PCR amplification of 730?bp fragment using VCR\VCF primers, the tested bacterial strains were identified as A. tumefaciens. This is the first report of crown gall on F. benjamina in Isfahan and Fars provinces of Iran.     

Core flooding tests to investigate the effects of IFT reduction and wettability alteration on oil recovery during MEOR process in an Iranian oil reservoir

Microbial enhanced oil recovery (MEOR) refers to the process of using bacterial activities for more oil recovery from oil reservoirs mainly by interfacial tension reduction and wettability alteration mechanisms. Investigating the impact of these two mechanisms on enhanced oil recovery during MEOR process is the main objective of this work. Different analytical methods such as oil spreading and surface activity measurements were utilized to screen the biosurfactant-producing bacteria isolated from the brine of a specific oil reservoir located in the southwest of Iran. The isolates identified by 16S rDNA and biochemical analysis as Enterobacter cloacae (Persian Type Culture Collection (PTCC) 1798) and Enterobacter hormaechei (PTCC 1799) produce 1.53 g/l of biosurfactant. The produced biosurfactant caused substantial surface tension reduction of the growth medium and interfacial tension reduction between oil and brine to 31 and 3.2 mN/m from the original value of 72 and 29 mN/m, respectively. A novel set of core flooding tests, including in situ and ex situ scenarios, was designed to explore the potential of the isolated consortium as an agent for MEOR process. Besides, the individual effects of wettability alteration and IFT reduction on oil recovery efficiency by this process were investigated. The results show that the wettability alteration of the reservoir rock toward neutrally wet condition in the course of the adsorption of bacteria cells and biofilm formation are the dominant mechanisms on the improvement of oil recovery efficiency.     

Identification of new promising plant-based lead compounds for inhibition of prokaryotic replicative DNA polymerases: combination of in silico and in vitro studies

Abstract

Emerging widespread bacterial resistance to current antibiotics with traditional targets is one of the major global concerns. Therefore, so many investigations are exploring the potential of other druggable macromolecules of bacteria such as replication machinery components that are not addressed by previous antibiotics. DNA polymerase is the major part of this machine. However, a few studies have been done on it so far. In this respect, we report the discovery of four new plant-based leads against DNA polymerase (pol) IIIC (three leads) and pol IIIE (one lead) of Gram-positive and negative bacteria by combining a sequentially constrained high-throughput virtual screenings on Traditional Chinese Medicine Database with in vitro assays. The compounds displayed relatively good levels of inhibitory effect. They were active against their designated targets at micromolar concentrations. The IC₅₀ values for them are ranged from 25 to 111?μM. In addition, they showed minimum inhibitory concentrations in the range of 8–128?μg/mL against five representatives of pathogenic bacteria species. However, they were inactive against Pseudomonas aeruginosa. Given these results, these leads hold promise for future modification and optimization to be more effective in lower concentrations and also against most of the important bacterial species.

Communicated by Ramaswamy H. Sarma     

Soluble guanylate cyclase isoenzymes: The expression of α1, α2, β1, and β2 subunits in the benign and malignant breast tumors

Soluble guanylate cyclase (sGC) encompasses α and β subunits. This study examined the expression of α1, α2, β1, and β2 subunits in the malignant and benign breast tumors using the Western blot analysis. Both benign and malignant tumors showed a significantly higher expression of the α1 subunit in comparison with normal tissues (p < 0.0001). In contrast, the expression of α2 and β2 sGC were significantly lower in these tumors than normal tissues (p < .0015 and p < .001, p < .007 and p < .0001, respectively). The expression level of α1 sGC was significantly correlated with ER + PR+ (p < .0001). A significant correlation was also detected for sGC-α1 and -α2 expression with c-erbB2-negative status (p < .01). However, the expression level of sGC was not associated with tumor stage, tumor grade, or other clinicopathological features. In conclusion, as the expression of α1 sGC is upregulated and α2 and β2 sGC are downregulated in malignant breast tumors. Variations in the expression of sGC isoenzymes may be suggested as an indicator to confirm the enzyme antitumor activity.     

COVID-19 under spotlight: A close look at the origin,transmission, diagnosis,and treatment of the 2019-nCoV disease

Months after the outbreak of a new flu-like disease in China, the entire world is now in a state of caution. The subsequent less-anticipated propagation of the novel coronavirus disease, formally known as COVID-19, not only made it to headlines by an overwhelmingly high transmission rate and fatality reports, but also raised an alarm for the medical community all around the globe. Since the causative agent, SARS-CoV-2, is a recently discovered species, there is no specific medicine for downright treatment of the infection. This has led to an unprecedented societal fear of the newly born disease, adding a psychological aspect to the physical manifestation of the virus. Herein, the COVID-19 structure, epidemiology, pathogenesis, etiology, diagnosis, and therapy have been reviewed.     

Algorithmic detection of the beginning and end of bipolar electrograms: Implications for novel methods to assess local activation time during atrial tachycardia

Activation mapping is required to effectively ablate atrial tachycardia (AT). Conventional tools to assess local activation time (LAT) are based upon the peak of the bipolar electrogram (B-EGM, LAT_Peak) and the maximal negative slope of the unipolar electrogram (U-EGM, LAT_Slope). Bipolar electrograms are influenced by wavefront direction, bipole orientation, and inter-electrode spacing causing ambiguity in peak detection, whereas unipolar electrograms are disturbed by the presence of far-field signals. We developed a new algorithm to detect the beginning and end of bipolar electrograms (t_begin and t_end). Then, we introduced new LAT methods related to the onset of B-EGMs (LAT_Onset), the center of mass of B-EGMs (LAT_CoM), and the slope of U-EGMs within a pre-defined window (LAT_Slope-hybrid).In total 3752 recordings from 31 AT patients were retrospectively analyzed. The signal-to-noise ratio (SNR) for B-EGMs was calculated to differentiate algorithmically high from low quality electrograms (HQ and LQ). In a subset of 328 B-EGMs, five experts validated the t_begin as determined by the algorithm by visual rating. The newly developed LAT methods were compared to the conventional LAT methods and to one another (Bland–Altman plots) in both HQ (n = 3003) and LQ EGMs (n = 749).The t_begin algorithm was accurate (deviation < ±10 ms) in 96 ± 4% of HQ and 91 ± 8% of LQ B-EGMs. BA plots revealed the following difference (bias) and variation in HQ and LQ EGMs respectively: (1) LAT_Onset vs. LAT_Peak: 27 ± 30 ms and 24 ± 62 ms; (2) LAT_CoM vs. LAT_Peak: 0 ± 16 ms and 2 ± 38 ms; (3) LAT_Slope-hybrid vs. LAT_Slope: 1 ± 32 ms and 15 ± 110 ms; (4) LAT_Onset vs. LAT_CoM: 22 ± 24 ms and 18 ± 22 ms; (5) LAT_Onset vs. LAT_Slope-hybrid: 16 ± 18 ms and 13 ± 22 ms; and (6) LAT_CoM vs. LAT_Slope-hybrid: 5 ± 20 ms and 4 ± 18 ms.In the present study, we introduced three new methods to assess local activation time in AT, based upon an algorithm detecting accurately the beginning and end of the B-EGM complex. BA analysis of the new methods showed similar variation in high and low quality EGMs, suggesting that they introduce less ambiguity than the conventional peak method. LAT_Onset consistently yielded an earlier activation moment. LAT_Slope-hybrid – by blanking far-field potentials – seems to be the optimal method for detection of the maximal negative slope in U-EGMs. Interestingly, LAT_CoM in B-EGMs coincided with the maximal negative slope in U-EGMs, suggesting its physiological sense and future use. The new LAT methods can be implemented in real-time mapping applications.     

Applications of MCNP simulation in treatment planning: a comparative study

Radiation and Environmental Biophysics - Monte Carlo codes have been used for approximately 80&nbsp;years to solve various problems in medical physics. In this paper, the importance of the...     

Hybrid of niosomes and bio-synthesized selenium nanoparticles as a novel approach in drug delivery for cancer treatment

Molecular Biology Reports - The current&nbsp;study&nbsp;intends to investigate a novel drug delivery system (DDS) based on niosomes structure (NISM) and bovine serum albumin (BSA) which was...     

The effect of Ccnb1ip1 insulator on monoclonal antibody expression in Chinese hamster ovary cells

Background

The increasing need for therapeutic monoclonal antibodies (mAbs) entails the development of innovative and improved expression strategies. Chromatin insulators have been utilized for the enhancement of the heterologous proteins in mammalian cells.

Methods and results

In the current study the Ccnb1ip1 gene insulator element was utilized to construct a novel vector system for the expression of an anti-CD52 mAb in Chinese hamster ovary (CHO) cells. The insulator containing (pIns-mAb) and control (pmAb) vectors were generated and stable cell pools were established using these constructs. The expression level in the cells created with pIns-mAb vector was calculated to be 233 ng/mL, and the expression rate in the control vector was 210 ng/mL, which indicated a 10.9% increase in mAb expression in pIns-mAb pool. In addition, analysis of mAb expression in clonal cells established from each pool showed a 10% increase in antibody productivity in the highest mAb producing clone derived from the pIns-mAb pool compared to the clone isolated from pmAb pool.

Conclusions

More studies are needed to fully elucidate the effects of Ccnb1ip1 gene insulator on recombinant therapeutic protein expression in mammalian cells. The combination of this element with other chromatin-modifying elements might improve its augmentation effect which could pave the way for efficient and cost-effective production of therapeutic drugs.