720 research outputs found
Modification of bacterial cell membrane to accelerate decolorization of textile wastewater effluent using microbial fuel cells: role of gamma radiation
The aim of the present work was to increase bacterial adhesion on anode via inducing membrane modifications to enhance textile wastewater treatment in Microbial Fuel Cell (MFC). Real textile wastewater was used in mediator-less MFCs for bacterial enrichment. The enriched bacteria were pre-treated by exposure to 1 KGy gamma radiation and were tested in MFC setup. Bacterial cell membrane permeability and cell membrane charges were measured using noninvasive dielectric spectroscopy measurements. The results show that pre-treatment using gamma radiation resulted in biofilm formation and increased cell permeability and exopolysaccharide production; this was reflected in both MFC performance (average voltage 554.67 mV) and decolorization (96.42%) as compared to 392.77 mV and 60.76% decolorization for non-treated cells. At the end of MFC operation, cytotoxicity test was performed for treated wastewater using a dermal cell line, the results obtained show a decrease in toxicity from 24.8 to 0 (v/v%) when cells were exposed to gamma radiation. Fourier-transform infrared (FTIR) spectroscopy showed an increase in exopolysaccharides in bacterial consortium exposed to increasing doses of gamma radiation suggesting that gamma radiation increased exopolysaccharide production, providing transient media for electron transfer and contributing to accelerating MFC performance. Modification of bacterial membrane prior to MFC operation can be considered highly effective as a pre-treatment tool that accelerates MFC performance
Histological and Histochemical Studies on the Ampulla of the Deferent Duct of Donkey (Equus asinus)
The present study was performed on the ampulla of the deferent duct of 24 sexually mature apparently healthy male donkeys (5 to 7 years) distributed over the four seasons of the year. The ampullary glands were branched tubulo-alveolar in type which they were opened in a central lumen. The luminal and the glandular epithelium were formed of principal and basal cells. Singly scattered rod- shaped cells were observed among the principal cells. PAS positive reactivity was observed in the surface and the glandular epithelium of the ampulla ductus deferentis. Only the luminal contents and the secretory materials attached to the apical border of the principal cells, showed positive reactivity for alcian blue. The present study presents the first description of the ampulla ductus deferentis of donkey. In addition to, it acts as a reservoir for sperms it had a secretory function for neutral and acid mucopolysaccharid
Histological and Morphometrical Studies on the Ampulla of the Deferent Duct of Donkey (Equus Asinus) in Different Seasons
The objective of this study is to describe the histological and histochemical structure of the ampulla ductus defrentis during different seasons of the year. The experiment was carried out on the ampulla of the deferent duct of 24 sexually mature apparently healthy male donkeys (5 to 7 years) distributed over the four seasons of the year. Both the lamina epithelialis and the epithelium lining the ampullary glands of the donkey showed highly significant (P < 0.01) seasonal variations. The interstitial tissue/ glandular tissue ratio of the ampullary glands showed as seasonal variations. The glandular epithelium of the ampullary glands of donkey had strong PAS positive reaction. This reaction decreased gradually during summer and autumn to reach its minimal amount during winter. In conclusions, the ampullary glands of donkey appeared more active during spring and this activity decreased gradually during the summer and autumn to reach it lowest activity during winter
3D Engineered Peripheral Nerve: Towards A New Era of Patient-Specific Nerve Repair Solutions
Reconstruction of peripheral nerve injuries (PNIs) with substance loss remains challenging because of limited treatment solutions and unsatisfactory patient outcomes. Currently, nerve autografting is the first-line management choice for bridging critical-sized nerve defects. The procedure, however, is often complicated by donor site morbidity and paucity of nerve tissue, raising a quest for better alternatives. The application of other treatment surrogates, such as nerve guides remains questionable, and inefficient in irreducible nerve gaps. More importantly, these strategies lack customization for personalized patient therapy, which is a significant drawback of these nerve repair options. This negatively impacts the fascicle-to-fascicle regeneration process, critical to restoring the physiological axonal pathway of the disrupted nerve. Recently, the use of additive manufacturing (AM) technologies has offered major advancements to the bioengineering solutions for PNI therapy. These techniques aim to reinstate the native nerve fascicle pathway using biomimetic approaches, thereby augmenting end-organ innervation. AM-based approaches, such as 3D bioprinting, are capable of biofabricating 3D engineered nerve graft scaffolds in a patient-specific manner with high precision. Moreover, realistic in vitro models of peripheral nerve tissues that represent the physiologically and functionally relevant environment of human organs could also be developed. However, the technology is still nascent and faces major translational hurdles. In this review, we spotlighted the clinical burden of PNIs and most up-to-date treatment to address nerve gaps. Next, a summarized illustration of the nerve ultrastructure that guides research solutions is discussed. This is followed by a contrast of the existing bioengineering strategies used to repair peripheral nerve discontinuities. In addition, we elaborated on the most recent advances in 3D printing (3DP) and biofabrication applications in peripheral nerve modeling and engineering. Finally, the major challenges that limit the evolution of the field along with their possible solutions are also critically analyzed
Clinical characteristics, treatment patterns and outcomes of Hispanic hypertensive patients
Hispanics are the largest and fastest-growing minority population in the United States, currently comprising about 16.3% (52 million) of the total population. With an increased prevalence of metabolic risk factors in this population, the rate of uncontrolled hypertension (HTN) in Hispanics significantly exceeds the rates observed among non-Hispanic blacks and whites. Unfortunately, data on HTN in Hispanics remains limited due to the under-representation of Hispanics in clinical trials; with most of the data primarily restricted to observational and retrospective subgroup analyses. This article aims to review the available data on prevalence, awareness and control of HTN, risk factors and some of the challenges unique to the Hispanics population. We also discuss treatment strategies derived from large HTN trials that included Hispanics
Nitrogen source, an important determinant of fatty acid accumulation and profile in scenedesmus obliquus
The potential of algae-based fuel technologies for manufacturing renewable biofuels has been attracting interest from the scientific community. Biomass productivity and cellular lipid content are important parameters affecting
the feasibility of using algae oil for biodiesel production. This study compares utilization of NaNO3, NH4Cland urea as different nitrogen sources in terms of their effects on biomass productivity, fatty acid profile and
accumulation in Scenedesmus obliquus. Cellular lipid accumulation was analyzed by gravimetric, fluorometric, and flow-cytometric methods, besides collecting spectrophotometric data for biomass productivity analysis. In addition,
fatty acid profiles were compared by using gas chromatography–mass spectrometry. The alga can utilize all tested nitrogen sources successfully however growth rates demonstrate differences. Gravimetric lipid content analysisshowed approximately a 1.5-fold increase in total lipid accumulation under NH4Cl regime when compared tothat of NaNO3 and a 2-fold increase when compared to that of urea at the end of ten days cultivation course.
Fatty acid profiles under different nitrogen regimes present variations especially under NH4Cl regime. Moreover,all lipid extracts mostly consist of saturated, straight- and branched-chain hydrocarbons of different chain lengths
ranging from C16–C20 which grant a suitable profile for biodiesel production.
Scenedesmus obliquus is a suitable species for biodiesel production. The results obtained from this study provide a better understanding of cultivation
characteristics of this important species and support potential, future biodiesel production
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