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41.
Lead (Pb) is a toxic heavy metal causing serious health risks to humans and animals. In the present study, cotton (Gossypium hirsutum L.) shells powder was used as adsorbent for the treatment of synthetic Pb-contaminated water. The batch scale biosorption capacity of cotton shells powder was evaluated to study the effects of Pb concentrations, adsorbent doses and contact time at constant pH (6) and temperature (25?°C). Results revealed that sorption of Pb increased (q?=?0.09–9.60?mg/g) with increasing Pb concentration (1–15?mg/L) and contact time (15–90?min) while decreasing adsorbent dose (1–0.1?g/100?mL). The maximum Pb removal (90%) was achieved at Pb concentration (1?mg/L), contact time (90?min) and adsorbent dose (1?g/100?mL). Freundlich isotherm model proved best fit for Pb sorption (R2?=?0.99). The cotton shells powder has microporous structure confirmed by SEM, and has BET surface area (45 m2/g) and pore size (2.3 µm). These surface moieties along with various functional groups (C-H, C-O, C=O, O-H, S=O) confirmed by FTIR analysis might involve in Pb removal by complexation and ion exchange mechanisms. The cotton shells powder biomass could be considered as promising adsorbent for the removal of Pb from contaminated water.  相似文献   
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43.
Various cultivars of red chilli were collected from a small town named Kunri, located in the province Sindh, Pakistan. This town is a hub of red chilli production in Asia. A total of 69 samples belonging to 6 cultivars were obtained and analysed for the occurrence of aflatoxins and Aspergillus flavus, to explore the potential of resistant and susceptible germplasm. Aflatoxins were detected by thin layer chromatography (TLC) and high performance liquid chromatography (HPLC), while A. flavus was isolated and identified using agar plate, blotter paper, deep freezing and dilution techniques. Molecular characterization using internal transcribed spacer (ITS) 1/4 and A. flavus specific FL1-F/R primers confirmed the identity of A. flavus. The data revealed that 67 and 75% samples contaminated with aflatoxin B1 (AFB1) and with A. flavus, respectively. A highly susceptible chilli cultivar was ‘Nagina’, showing 78.8% frequency of total aflatoxins (1.2–600 μg/kg) and a mean of 87.7 μg/kg for AFB1 and 121.9 μg/kg for total aflatoxins. A. flavus was detected with 93% frequency and 2.14 × 104 colony forming units. In contrast, cultivars ‘Kunri’ and ‘Drooping Type’ were found to be resistant, with low levels of aflatoxins and fungal counts. The study was conducted for the first time to explore two potential cultivars that were less susceptible towards A. flavus and aflatoxin contamination. These cultivars could be preferably cultivated and thereby boost Pakistan’s chilli production.  相似文献   
44.
Journal of Plant Growth Regulation - Fullerenols are carbon nanoparticles that have been declared as free radical sponges. There is a need to take a prudent path toward its applications in various...  相似文献   
45.
RNA interference is one of the prosperous approaches for cancer treatment. However, small interfering RNA (siRNA) delivery to cancer cells has been faced with various challenges restricting their clinical application over the decades. Since ROR1 is an onco-embryonic gene overexpressed in many malignancies, suppression of ROR1 by siRNA can potentially fight cancer. Herein, a delivery system for ROR1 siRNA based on HIV-1 TAT peptide-capped gold nanoparticles (GNPs) was developed to treat breast cancer. Besides, we introduced a new feasible method for conjugating the peptide to the nanoparticles. Since the GNPs have high affinity to the sulfur, the findings demonstrated the peptide successfully conjugated to the nanoparticles via Au–S bonds. As positively charged nanoparticles showed high cellular uptake, we could use a low concentration of nanoparticles led to high efficient gene transfection with negligible cytotoxicity that was confirmed by flow cytometry, confocal microscopy, gel retardation, and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Following transfection, downregulation of ROR1 and its targeted gene, CCND1, induced apoptosis in cancer cells. In conclusion, the reported capped GNPs could be potentially utilized for delivering negatively charged therapeutic agents in particular genes.  相似文献   
46.

Objective

To assess the efficacy and safety of percutaneous testicular biopsy to provide sperm cells for ICSI in male patients with azoospermia not amenable to surgical treatment.

Materials and methods

From October 1995 to December 2001, 175 biopsies were performed in men with azoospermia to provide material for intracytoplasmic sperm injection. Azoospermia was obstructive (OA) in 41 cases and non-obstructive (NOA) in 134 cases. Open biopsy was performed in the first 15 patients in the series and percutaneous biopsy was performed on an outpatient basis, under local anesthesia, with a Biopty Gun® (14G needle), in the subsequent patients as the first step in management. Open surgical biopsies were performed in another 15 patients following a sperm cell-negative percutaneous biopsy.

Results

All biopsies performed for OA were positive, but only 51/134 biopsies (38%) were positive in the NOA group. The material provided by percutaneous biopsy, when positive for sperm cells, was always sufficient to perform ICSI. When percutaneous biopsy was negative, open surgical biopsy failed to give better results. Five men developed minor complications (acute hematocele) following percutaneous biopsies requiring reoperation for hemostasis (3.12%). No major complications were observed. Results were comparable in terms of fertilization and pregnancy rates whether fresh or frozen-thawed sperm was used.

Conclusion

Percutaneous testicular sperm extraction is a safe, well-tolerated and cost-effective procedure in the management of male-factor infertility related to azoospermia.  相似文献   
47.
LiF:Mg,Cu,Ag is a new dosimetry material that is similar to LiF:Mg,Cu,P in terms of dosimetric properties. The effect of the annealing temperature in the range of 200 to 350°C on the thermoluminescence (TL) sensitivity and the glow curve structure of this material at different concentrations of silver (Ag) was investigated. It has been demonstrated that the optimum values of the annealing temperature and the Ag concentration are 240°C and 0.1 mol% for better sensitivity, respectively. The TL intensity decreases at annealing temperatures lower than 240°C or higher than 240°C, reaching a minimum at 300°C and then again increases for various Ag concentrations. It was observed that the glow curve structure altered and the area under the low temperature peak as well as the area under the main dosimetric peak decreased with increasing annealing temperature. The position of the main dosimetric peak moved in the direction of higher temperatures, but at 320 and 350°C annealing temperatures, it shifted to lower temperatures. It was also observed that the TL sensitivity could partially be recovered by a combined annealing procedure.  相似文献   
48.
The hexose monophosphate (HMP) shunt acts as an essential component of cellular metabolism in maintaining carbon homeostasis. The HMP shunt comprises two phases viz. oxidative and nonoxidative, which provide different intermediates for the synthesis of biomolecules like nucleotides, DNA, RNA, amino acids, and so forth; reducing molecules for anabolism and detoxifying the reactive oxygen species during oxidative stress. The HMP shunt is significantly important in the liver, adipose tissue, erythrocytes, adrenal glands, lactating mammary glands and testes. We have researched the articles related to the HMP pathway, its metabolites and disorders related to its metabolic abnormalities. The literature for this paper was taken typically from a personal database, the Cochrane database of systemic reviews, PubMed publications, biochemistry textbooks, and electronic journals uptil date on the hexose monophosphate shunt. The HMP shunt is a tightly controlled metabolic pathway, which is also interconnected with other metabolic pathways in the body like glycolysis, gluconeogenesis, and glucuronic acid depending upon the metabolic needs of the body and depending upon the biochemical demand. The HMP shunt plays a significant role in NADPH2 formation and in pentose sugars that are biosynthetic precursors of nucleic acids and amino acids. Cells can be protected from highly reactive oxygen species by NADPH 2. Deficiency in the hexose monophosphate pathway is linked to numerous disorders. Furthermore, it was also reported that this metabolic pathway could act as a therapeutic target to treat different types of cancers, so treatments at the molecular level could be planned by limiting the synthesis of biomolecules required for proliferating cells provided by the HMP shunt, hence, more experiments still could be carried out to find additional discoveries.  相似文献   
49.
Sexuality in fungi has long been a matter of concerns and debates that always necessitated extensive analysis of the relationship between organisms assumed to represent different developmental forms of the same organism. Moreover, mating-virulence correlation and the growing worry of opportunistic fungal infections in immunocompromised states associated with AIDS, cancer chemotherapy and organ transplantation protocols have been critically addressed nowadays. In view of that, we genetically characterized Aspergillus chevalieri, Aspergillus nidulans, Aspergillus tetrazonus (quadrilineatus) and their teleomorphs with RAPD analysis using 5'-d[AACGCGCAAC]-3' and 5'-d[CCCGTCAGCA]-3' primers. The reported similarities between the sexual and the asexual forms of the tested species, using Dice coefficient, ranged between 40% and 70% which holds pretty much with the current systematics of the genus. The study presents a rapid consistent method for identification of A. chevalieri, A. nidulans, A. tetrazonus (quadrilineatus) and their teleomorphs based on the banding pattern of RAPD-generated fragments that can be reliably used ahead of further applications on these species.  相似文献   
50.
Cadmium (Cd) is highly toxic metal for plant metabolic processes even in low concentration due to its longer half-life and non-biodegradable nature. The current study was designed to assess the bioremediation potential of a Cd-tolerant phytobeneficial bacterial strain Bacillus sp. SDA-4, isolated, characterized and identified from Chakera wastewater reservoir, Faisalabad, Pakistan, together with spinach (as a test plant) under different Cd regimes. Spinach plants were grown with and without Bacillus sp. SDA-4 inoculation in pots filled with 0, 5 or 10 mg kg−1 CdCl2-spiked soil. Without Bacillus sp. SDA-4 inoculation, spinach plants exhibited reduction in biomass accumulation, antioxidative enzymes and nutrient retention. However, plants inoculated with Bacillus sp. SDA-4 revealed significantly augmented growth, biomass accumulation and efficiency of antioxidative machinery with concomitant reduction in proline and MDA contents under Cd stress. Furthermore, application of Bacillus sp. SDA-4 assisted the Cd-stressed plants to sustain optimal levels of essential nutrients (N, P, K, Ca and Mg). It was inferred that the characterized Cd-tolerant PGPR strain, Bacillus sp. SDA-4 has a potential to reduce Cd uptake and lipid peroxidation which in turn maintained the optimum balance of nutrients and augmented the growth of Cd-stressed spinach. Analysis of bioconcentration factor (BCF) and translocation factor (TF) revealed that Bacillus sp. SDA-4 inoculation with spinach sequestered Cd in rhizospheric zone. Research outcomes are important for understanding morpho-physio-biochemical attributes of spinach-Bacillus sp. SDA-4 synergy which might provide efficient strategies to decrease Cd retention in edible plants and/or bioremediation of Cd polluted soil colloids.  相似文献   
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