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311.
S. A. Abbasi Tabassum-Abbasi G. Ponni S. M. Tauseef 《International journal of phytoremediation》2019,21(2):160-169
In a first-ever report on this subject, it is shown that a common amphibious plant joyweed (Alternanthera sessilis) can be used in rapid and efficient treatment of biodegradable wastewaters, typified by domestic sewage. The plant was effective when used indoors under artificial lighting, as well as outdoors. It enabled treatment of sewage, varying widely in strength (from 300?mg/L to 1800?mg/L in chemical oxygen demand), to the extent of 78.9–83.9%. It was also able to remove biological oxygen demand, suspended solids, phosphorous, nitrogen, and the heavy metal copper to the extent of 87%, 93%, 45%, and 43%, respectively. Over 99% of total coliforms, faecal coliforms, and faecal streptococci were also removed. The treatment was very swiftly achieved, at a hydraulic retention time of just 6?h, in the “sheet flow root level” (SHEFROL®) bioreactor developed earlier by us and of which a patent claim has been registered. The findings indicate that A. sessilis has the potential to affect primary, secondary, and tertiary treatment of domestic sewage along with significant pathogen removal in a single process step when used in SHEFROL® bioreactors. 相似文献
312.
313.
Recent work was conducted to predict the structure of functionally distinct regions of Avicennia marina peroxidase (AP) by using the structural coordinates of barley grains peroxidase as the template. This enzyme is utilized
by all living organisms in many biosynthetic or degradable processes and in defense against oxidative stress. The homology
model showed some distinct structural changes in the heme, calcium, and substrate-binding regions. Val53 was found to be an
important coordinating residue between distal calcium ion and the distal heme site while Ser176 is coordinated to the proximal
histidine through Ala174 and Leu172. Different ionic and hydrogen-bonded interactions were also observed in AP. Analyses of
various substrate–enzyme interactions revealed that the substrate-binding pocket is provided by the residues, His41, Phe70,
Gly71, Asp138, His139, and Lys176; the later three residues are not conserved in the peroxidase family. We have also performed
structural comparison of the A. marina peroxidase with that of two class III salt-sensitive species, peanut and soybean. Four loop regions were found to have largest
structural deviation. The overall protein sequence was also analyzed for the presence of probable post-translational modification
sites and the functional significance of these sites were outlined. 相似文献
314.
Small interfering RNA (siRNA) molecules have great potential for developing into a future therapy for breast cancer. To overcome
the issues related to rapid degradation and low transfection of naked siRNA, polyethylenimine (PEI)-coated human serum albumin
(HSA) nanoparticles have been characterized and studied here for efficient siRNA delivery to the MCF-7 breast cancer cell
line. The optimized nanoparticles were ~90 nm in size, carrying a surface charge of +26 mV and a polydispersity index (PDI)
less than 0.25. The shape and morphology of the particles was studied using electron microscopy. A cytotoxicity assessment
of the nanoparticles showed no correlation of cytotoxicity with HSA concentration, while using high molecular weight PEI (MW
of 70 against 25 kDa) showed higher cytotoxicity. The optimal transfection achieved of fluorescin-tagged siRNA loaded into
PEI-coated HSA nanoparticles was 61.66 ± 6.8%, prepared with 6.25 μg of PEI (25 kDa) added per mg of HSA and 20 mg/ml HSA,
indicating that this nonviral vector may serve as a promising gene delivery system. 相似文献
315.
316.
Non-unions pose complications in fracture management that can be treated using electrical stimulation (ES). Bone marrow mesenchymal stem cells (BMMSCs) are essential in fracture healing; however, the effect of different clinical ES waveforms on BMMSCs cellular activities remains unknown. We compared the effects of direct current (DC), capacitive coupling (CC), pulsed electromagnetic field (PEMF) and degenerate wave (DW) on cellular activities including cytotoxicity, proliferation, cell-kinetics and apoptosis by stimulating human-BMMSCs 3 hours a day, up to 5 days. In addition, migration and invasion were assessed using fluorescence microscopy and by quantifying gene and protein expression. We found that DW had the greatest proliferative and least apoptotic and cytotoxic effects compared to other waveforms. DC, DW and CC stimulations resulted in a higher number of cells in S phase and G(2)/M phase as shown by cell cycle analysis. CC and DW caused more cells to invade collagen and showed increased MMP-2 and MT1-MMP expression. DC increased cellular migration in a scratch-wound assay and all ES waveforms enhanced expression of migratory genes with DC having the greatest effect. All ES treated cells showed similar progenitor potential as determined by MSC differentiation assay. All above findings were shown to be statistically significant (p<0.05). We conclude that ES can influence BMMSCs activities, especially DW and CC, which show greater invasion and higher cell proliferation compared to other types of ES. Application of DW or CC to the fracture site may help in the recruitment of BMMSCs to the wound that may enhance rate of bone healing at the fracture site. 相似文献
317.
Vermicomposting of the pre-composted leaf litter of acacia (Acacia auriculiformis) was studied in reactors of identical volume but with surface area: height ratios varying from 4 to 250. In separate sets of experiments with these reactors, epigeic earthworm species Eudrilus eugeniae and anecic earthworm species Lampito mauritii were employed at densities of 75 and 150 adult animals per litre of reactor volume.The results reveal that greater the surface area: volume ratio of the reactor, higher is the vermicast output in terms of vermicast output per animal; the more densely populated reactors were comparatively under-productive.Even as the vermicast production remained consistently high in all the reactors, there was significant earthworm mortality throughout the course of the experiments and the worms who survived, steadily lost weight with time. A detailed investigation of the possible causes revealed that, whereas the C:N ratio of acacia compost was comparable with that of other substrates; the polyphenols and lignin content were much higher. Studies by other authors on leaf litter consumption by earthworms in natural or man-made forests have indicated that leaf litter rich in polyphenols and lignin are not preferred by most species of earthworm. This may perhaps be the reason for the high rate of mortality and weight loss in earthworms forced to feed upon acacia in the experiments conducted by the authors. 相似文献
318.
Mara Jana Broadhurst Amir Ardeshir Bittoo Kanwar Julie Mirpuri Uma Mahesh Gundra Jacqueline M. Leung Kirsten E. Wiens Ivan Vujkovic-Cvijin Charlie C. Kim Felix Yarovinsky Nicholas W. Lerche Joseph M. McCune P'ng Loke 《PLoS pathogens》2012,8(11)
Idiopathic chronic diarrhea (ICD) is a leading cause of morbidity amongst rhesus monkeys kept in captivity. Here, we show that exposure of affected animals to the whipworm Trichuris trichiura led to clinical improvement in fecal consistency, accompanied by weight gain, in four out of the five treated monkeys. By flow cytometry analysis of pinch biopsies collected during colonoscopies before and after treatment, we found an induction of a mucosal TH2 response following helminth treatment that was associated with a decrease in activated CD4+ Ki67+ cells. In parallel, expression profiling with oligonucleotide microarrays and real-time PCR analysis revealed reductions in TH1-type inflammatory gene expression and increased expression of genes associated with IgE signaling, mast cell activation, eosinophil recruitment, alternative activation of macrophages, and worm expulsion. By quantifying bacterial 16S rRNA in pinch biopsies using real-time PCR analysis, we found reduced bacterial attachment to the intestinal mucosa post-treatment. Finally, deep sequencing of bacterial 16S rRNA revealed changes to the composition of microbial communities attached to the intestinal mucosa following helminth treatment. Thus, the genus Streptophyta of the phylum Cyanobacteria was vastly increased in abundance in three out of five ICD monkeys relative to healthy controls, but was reduced to control levels post-treatment; by contrast, the phylum Tenericutes was expanded post-treatment. These findings suggest that helminth treatment in primates can ameliorate colitis by restoring mucosal barrier functions and reducing overall bacterial attachment, and also by altering the communities of attached bacteria. These results also define ICD in monkeys as a tractable preclinical model for ulcerative colitis in which these effects can be further investigated. 相似文献
319.
Akbarzadeh S Ghasemi S Kalantarhormozi M Nabipour I Abbasi F Aminfar A Jaffari SM Motamed N Movahed A Mirzaei M Rahbar AR 《Gynecological endocrinology : the official journal of the International Society of Gynecological Endocrinology》2012,28(7):521-524
Polycystic ovary syndrome (PCOS) is an endocrine disorder in women. Omentin-1 and vaspin are secretary adipokines that are produced by the visceral adipose tissue. These levels change in obese women with PCOS. The aim of this study is to investigate whether omentin and vaspin levels change in nonobese PCOS subjects. This study is a cross-sectional case control study in which 39 women with PCOS were picked out for this study. The inclusion criteria were based on the Rotterdam 2003 diagnostic criteria. The control group consisted of 39 women with normal pelvic sonographic reports having regular menstruation and showing no signs of infertility. The fasting plasma glucose (FPG), triglyceride (TG), Chol, and high-density lipoprotein cholesterol (HDL-C), insulin, testosterone, omentin and vaspin were measured by the enzymatic methods. The differences within these groups were calculated by the un-paired t-test and the Mann-Whitney test. The results from this study show a significant increase in the amount of insulin, testosterone, homeostasis model assessments for insulin resistance, TG and lower HDL in the patient group. No significant differences were seen in omentin, vaspin, FPG, Cho, low-density lipoprotein, very low-density lipoprotein cholesterol, blood urea nitrogen, Cr and homeostasis model assessments for B cell function levels between groups. Results show that PCOS is not a determinant of decreased omentin and vaspin plasma levels and those high androgen level and insulin resistances are warning signs of PCOS. 相似文献
320.
Ali Abbasi Stephan J. L. Bakker Eva Corpeleijn Daphne L. van der A Ron T. Gansevoort Rijk O. B. Gans Linda M. Peelen Yvonne T. van der Schouw Ronald P. Stolk Gerjan Navis Annemieke M. W. Spijkerman Joline W. J. Beulens 《PloS one》2012,7(12)