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Open access

Niyazi Acer, Mehmet Sait Dundar and Serap Bastepe-Gray

Abstract

The brain consist of about 75 percent water. Diffusion tensor imaging (DTI) is an advanced magnetic resonance (MR) technique imaging that has been developed for diagnostic and research in medicine. It can be use DTI tractography to better understand degenerating axons of white matter lesions in some neurological diseases such as MS, AD, trauma, cerebral ischemia, epilepsy, brain tumors and metabolic disorders.

Open access

Matei Sorin, Matei Gabi-Mirela and Dumitrașcu Monica

Abstract

Soils from rural zones with high natural value (HNV) agriculture systems are an important source of beneficial microbial species that can be useful for various biotechnological purposes, such as transfer of suppressiveness against plant pathogens from suppressive to disease-inducing soils by using inoculation with antagonistic selected strains. The main goal of the paper was to present the results of the research carried out on strains isolated from soil microbial populations in HNV agriculture system (Mureș county, Romania) responsible for specific suppressiveness against soil-borne phytopathogens. The dual culture method was used for assessing the mechanisms involved in antagonism against a plant pathogenic strain from genus Fusarium. The global microbial activity measured as soil respiration was intense. Total counts of bacteria and fungi estimated by dilution plate were also high. The community of heterotrophic aerobic bacteria included 13 species. Associations of fluorescent pseudomonads and actinomycetes were dominant and presented antagonistic activity against Fusarium. Twenty fungal species presented cellulolytic capability evidenced by growth on culture media with cellulose as sole source of carbon. Over cellulolytic capacity, the selected isolate of Trichoderma viride presented antagonistic activity against pathogenic Fusarium strain. Both biochemical mechanism and hyperparasitism were evidenced as involved in its antifungal activity.

Open access

Vincenza Precone, Munis Dundar, Tommaso Beccari, Eda Tahir Turanli, Stefano Cecchin, Giuseppe Marceddu, Elena Manara and Matteo Bertelli

Abstract

Analytical laboratory results greatly influence medical diagnosis, about 70% of medical decisions are based on laboratory results. Quality assurance and quality control are designed to detect and correct errors in a laboratory’s analytical process to ensure both the reliability and accuracy of test results. Unreliable performance can result in misdiagnosis and delayed treatment. Furthermore, improved quality guarantees increased productivity at a lower cost. Quality assurance programmes include internal quality control, external quality assessment, proficiency surveillance and standardization. It is necessary to try to ensure compliance with the requirements of the standards at all levels of the process. The sources of these standards are the International Standards Organization (ISO), national standards bodies, guidelines from professional organisations, accreditation bodies and governmental regulations. Laboratory networks increase the performance of laboratories in support of diagnostic screening programme. It is essential that genetic laboratories of a network have procedures underpinned by a robust quality assurance system to minimize errors and to reassure the clinicians and the patients that international standards are being met. This article provides an overview of the bases of quality assurance and its importance in genetic tests and it reports the EBTNA quality assurance system which is a clear and simple system available for access to adequate standardization of a genetic laboratory’s network.

Open access

Gabi-Mirela Matei, Sorin Matei, Elena Maria Drăghici and Marian Stoian

Abstract

The presence of oil hydrocarbons and salts in soils has as consequence the poor growth of plants due to the low availability of nutrients caused by unappropriate water regime, increased soil toxicity and the deterioration of soil structure. The present research has as main purpose the improvement of the bean plants (cultivar UNIDOR) growth and to stimulate microbial activity in rhizosphere using various natural stimulators and fertilizers (AMALGEROL,VERMIPLANT, POCO, IGUANA and FORMULEX) in greenhouse experiments on oil-polluted soil from Icoana farm, Olt county. The total counts of microorganisms (heterotrophic aerobic bacteria and filamentous fungi) were estimated by dilution plate method. The global microbial activity was measured as soil respiration by substrate-induced respiration method. Total bean plants biomass accumulation significantly increased under the influence of natural stimulators and fertilizers added (excepting IGUANA) when compared to untreated control. The best results were recorded for VERMIPLANT. Natural products induced activation of physiological activities of soil microbiota reflected in increased values of CO2 released by respiration, lower levels of colonization with phytopathogenic species, the domination of fluorescent pseudomonads, actinomycetes and cellulolytic fungi, too. The particular aspect of paper circular chromatograms reflected qualitative differences between rhizosphere soils determined by the effect of treatments with natural stimulators and fertilizers.

Open access

Samuel O. Onoja, Osborn Chinagorom, Chinyere B. C. Ikpa, Kelechi G. Madubuike, Ihechiluru I. Ezeigbo, Solomon N. Ijioma, Aruh O. Anaga and Maxwell I. Ezeja

Abstract

Gastric ulcer is one of the common cause of hospital consultation with an increasing prevalence worldwide and it is traditionally managed with herbal medicine in the developing countries. This study investigated the gastroprotective effects of methanol extract of Eremomastax speciosa leaf in rats. Cold maceration in 80% methanol was adopted during extract preparation while gas chromatography mass spectroscopy (GC-MS) was employed in the phytochemical analysis. The doses of 25, 50 and 100 mg/kg E. speciosa were used on ethanol-and indomethacin-induced gastric ulcer models in rats. The shay rat method was used to determine the effects of ESE on gastric acidity while the anticholinergic and antihistaminic activities were investigated on isolated rabbit jejunum ex vivo. The GC-MS analysis identified six bioactive compounds. Both ESE and cimetidine significantly (p < 0.05) reduced the severity of indomethacin- and ethanol-induced gastric injuries and gastric acid contents in Shay rats. The extract elicited concentration-dependent relaxation of isolated rabbit jejunum and reduced the contraction induced by both acetylcholine and histamine in the same tissue. The findings showed that ESE protected the rats against chemical-induced gastric ulcer through anticholinergic and antihistaminic mechanisms.

Open access

Nathalie Picollet-D’hahan, Axel Tollance, Cristina Belda Marin, Lavinia Liguori, Christophe Marquette, Odile Filhol-Cochet, Isabelle Vilgrain, Guillaume Laffitte, Florence Rivera, Jean-Pierre Alcaraz, Jacques Thélu, Olivier Nicoud, Thibaud Moufle-Milot, Maxime Legues, Ali Bouamrani, Adrien Mombrun, Benoit Gilquin, Sophie Gerbaud, Patricia Obeid, Fréderique Kermarrec, Xavier Gidrol and Donald K. Martin

Abstract

We report our approach to creating a microfluidic chip (namely UroLOC) that mimics the acinar/tubular structure and the luminal microenvironment of exocrine glands. The chip utilises a nanostructured membrane that is designed to provide a 3-dimensional supporting scaffold for the growth of exocrine acinus epithelial cells. The nanostructured membrane was produced using layer-by-layer assembly of polyelectrolytes, and formed into 3-dimensional hemispherical cavities and “finger-like” structures in order to mimic the natural architecture of acini found in exocrine glands. We utilised normal (PNT2) and cancerous (PC3, LNCaP) prostate epithelial cells to demonstrate the proof-of-concept of using MALDI (Matrix Assisted Laser Desorption Ionisation) profiling of secretions collected after 48 hours of cell growth, with no concentration or purification steps and without any a priori on the knowledge of targeted proteins. This MALDI profiling analysis of the crude supernatants from 3 different cell lines (PNT2, PC3 and LNCaP) demonstrated the capacity of the MALDI profiling approach to discriminate between the different secretome signatures. The UroLOC concept and secretome profiling that we describe opens new opportunities in terms of liquid-biopsy based diagnosis, particularly for the early stages of carcinogenesis.

Open access

Habib Ahmad, Misbah Ahmad, Shahid Ali, M. Rauf Khattak, Wajeeha Shaheen, Jawad A. Gilani and Khalil Ahmad

Abstract

The goal of radiotherapy is to deliver prescribed dose to the target volume and simultaneously minimize the dose to the healthy organs. The purpose of this work was to verify the accuracy of calculations carried out with a treatment planning system (TPS). Measurements carried out with thermoluminescence detectors (TLDs) were compared with doses calculated with TPS. Doses were measured and calculated both in the open beam’s region and under individual blocks. Measurements were performed in the Randophantom. The work was carried out for photon beams generated in the Varian CLINAC 2100C accelerator. The maximum / minimum percentage differences between measured and calculated doses were 4.9/0.6%, 2.6/0%, and 3.5%/0.5% in open, shielded and partially shielded points, respectively. Differences between the measured and calculated doses were within acceptable limits.

Open access

Thokchom Dewan Singh

Abstract

In the radiotherapy practice, regulator defines risk in terms of physically measurable quantities and attempt to implement the results obtained from the risk assessment of this practice, using quantitative approach. Although such approach has significantly brought down radiation dose, injuries and fatalities to the workers as compared to the radiotherapy practices before World War II, the objectivity concept of risk that limits the assessment regarding physically measurable quantities is widely urged throughout the world. This study examined how the risk associated with radiotherapy practice has been perceived, and experienced by both professional and non-professional workers in the radiotherapy facilities located in Manipur, Meghalaya, and Assam. This study found that professional and nonprofessional workers exhibited different risk perception on the same physical risk. Such different risk perceptions influenced the establishment of radiological protection systems in the facility. Non-professional workers are more likely to be the affected group in a facility having weak radiological protection systems.

Open access

Krisanat Chuamsaamarkkee, Putthiporn Charoenphun, Natthaporn Kamwang, Sahakan Monthonwattana, Wirote Changmuang, Kittiphong Thongklam, Arpakorn Kositwattanarerk, Yoch Anongpornjossakul, Wichana Chamroonrat and Chanika Sritara

Abstract

Background: 131I-metaiodobenzylguanidine (mIBG) offers an effectively targeted radionuclide therapy in pediatric patients. According to radiation protection authority in our country, the patient treated with high-dose (>1100 MBq) radioiodine is recommended to stay in the hospital. Hence, this study intends to measure the radiation exposure in nonlead-lined treatment room installing with portable lead shields located in general pediatric ward and surrounding areas. In addition, this study also aims to measure the radiation exposure to the family caregiver in pediatric patients received high dose 131I-mIBG.

Methods: Environmental OSL (optically stimulated luminescence) monitoring devices (InLight®, Al2O3:C) were prepared and calibrated by Thailand Institute of Nuclear Technology (TINT). Twenty-five set of OSLs were placed in and surrounded the treatment room. Dose to family caregiver was recorded by digital semiconductor dosimeter (ALOKA PDM-112) also calibrated by TINT. The measurement was carried for four pediatric patients treated with 131IMIBG (activity 3700 – 5500 MBq).

Results: The ambient doses equivalent and the dose rate were analyzed, the limit of 10 and 0.5 μSv/h are accepted for radiation worker and member of the public, respectively. The dose rate around the patient bed and toilet were high as expected. Dose rates at the wall of adjacent room and corridor were slightly greater than the public limit (range 1.82 to 4.48 μSv/h). Remarkably, the dose rates at caregiver chair (outside the shielding) were exceeded the limits (30.57 ± 5.69 μSv/h). Consequently, this was correlated with high personal dose equivalent to family caregivers which listed as 175, 1632, 6760 and 7433 μSv for the patient age of 15, 5, 1 and 1 year respectively.

Conclusion: These radiation monitoring data provided the important information to manage radiation protection and aware of radiation exposure when using non-lead-lined treatment room in general pediatric ward.

Open access

Behrouz Rasuli, Naser Tabkhi, Ebrahim Kalantar, Vahid Zarezade and Mohammad Bagher shiran

Abstract

The aim of this work was to investigate the potential of high frequency ultrasound for the cleaning of a Polysulfone (PSU) ultrafiltration membrane used in hemodialysis. The blood substitute solution flowing through the hollow fiber membrane used in the High Flux F60 dialyzers has been sonicated by ultrasonic (US) waves with 1 MHz frequency and 2 W/cm2 in situ intensity. The solution was comprised of toxic compounds such as Urea, Creatinine, Vitamin B12 and Inulin. The effect of US was represented by comparison of the clearance in both OFF and ON ultrasound conditions. The results of these studies have been demonstrated that US can enhance the permeability of the PSU dialyzer membrane. Results revealed that US had significant effect (p-value ˂ 0.05) on the clearance of Inulin as a large molecule (5200 D) and accelerated its filtration by 28%. The proposed dialysis method can be used alongside the existing dialysis machine.