143 research outputs found
Biomedical waste management by using nanophotocatalysts: The need for new options
Biomedical waste management is getting significant consideration among treatment technologies, since insufficient management can cause danger to medicinal service specialists, patients, and their environmental conditions. The improvement of waste administration protocols, plans, and policies are surveyed, despite setting up training programs on legitimate waste administration for all healthcare service staff. Most biomedical waste substances do not degrade in the environment, and may also not be thoroughly removed through treatment processes. Therefore, the long-lasting persistence of biomedical waste can effectively have adverse impact on wildlife and human beings, as well. Hence, photocatalysis is gaining increasing attention for eradication of pollutants and for improving the safety and clearness of the environment due to its great potential as a green and eco-friendly process. In this regard, nanostructured photocatalysts, in contrast to their regular counterparts, exhibit significant attributes such as non-toxicity, low cost and higher absorption efficiency in a wider range of the solar spectrum, making them the best candidate to employ for photodegradation. Due to these unique properties of nanophotocatalysts for biomedical waste management, we aim to critically evaluate various aspects of these materials in the present review and highlight their importance in healthcare service settings
ATM and Artemis promote homologous recombination of radiation-induced DNA double-strand breaks in G2
Homologous recombination (HR) and nonāhomologous end joining (NHEJ) represent distinct pathways for repairing DNA doubleāstrand breaks (DSBs). Previous work implicated Artemis and ATM in an NHEJādependent process, which repairs a defined subset of radiationāinduced DSBs in G1āphase. Here, we show that in G2, as in G1, NHEJ represents the major DSBārepair pathway whereas HR is only essential for repair of ā¼15% of Xā or Ī³ārayāinduced DSBs. In addition to requiring the known HR proteins, Brca2, Rad51 and Rad54, repair of radiationāinduced DSBs by HR in G2 also involves Artemis and ATM suggesting that they promote NHEJ during G1 but HR during G2. The dependency for ATM for repair is relieved by depleting KAPā1, providing evidence that HR in G2 repairs heterochromatināassociated DSBs. Although not core HR proteins, ATM and Artemis are required for efficient formation of singleāstranded DNA and Rad51 foci at radiationāinduced DSBs in G2 with Artemis function requiring its endonuclease activity. We suggest that Artemis endonuclease removes lesions or secondary structures, which inhibit end resection and preclude the completion of HR or NHEJ
Gum Tragacanth (GT): A Versatile Biocompatible Material beyond Borders
The use of naturally occurring materials in biomedicine has been increasingly attracting the researchers' interest and, in this regard, gum tragacanth (GT) is recently showing great promise as a therapeutic substance in tissue engineering and regenerative medicine. As a polysaccharide, GT can be easily extracted from the stems and branches of various species of Astragalus. This anionic polymer is known to be a biodegradable, non-allergenic, non-toxic, and non-carcinogenic material. The stability against microbial, heat and acid degradation has made GT an attractive material not only in industrial settings (e.g., food packaging) but also in biomedical approaches (e.g., drug delivery). Over time, GT has been shown to be a useful reagent in the formation and stabilization of metal nanoparticles in the context of green chemistry. With the advent of tissue engineering, GT has also been utilized for the fabrication of three-dimensional (3D) scaffolds applied for both hard and soft tissue healing strategies. However, more research is needed for defining GT applicability in the future of biomedical engineering. On this object, the present review aims to provide a state-of-the-art overview of GT in biomedicine and tries to open new horizons in the field based on its inherent characteristics
Association of RS4784227-casc16 (Loc643714 locus) and RS4782447-ACSF3 polymorphisms and their association with breast cancer risk among iranian population
Peer reviewedPublisher PD
Analysis of chromosome aberrations by FISH and Giemsa assays in lymphocytes of cancer patients undergoing whole-body irradiation: comparison of in vivo and in vitro irradiation
Abstract. Studies of the frequencies of chromosome exchange aberrations in peripheral lymphocytes provide useful Purpose : To study the cytogenetic eVects of fractionated radiobiodosimetric information (IAEA 1986, Darroudi therapy in peripheral blood lymphocytes of ve cancer patients. 2000). For individual dose estimation, a calibration In vitro experiments were performed in parallel using the same dose-response curve constructed for human lympho- patients undergoing protracted whole-body irradiGiemsa-stained preparations were used to score unstable ation at low doses before local radiotherapy at high aberrations following in vivo and in vitro exposure. dose. Results: A linear dose-response curve was determined for both dicentrics and translocations. The in vivo frequency of translocations was higher than for dicentrics. Dose-response curves Materials and methods generated for translocations following in vivo and in vitro irradiation yielded similar frequencies. In contrast, for dicentrics, in 2.1. Subjects vitro irradiation yielded a higher frequency when compared with data generated following in vivo exposure. The study was performed on ve patients aged Conclusions : For dose reconstruction purposes, translocations fre-23-70 years, one woman and four men, with quency seems to be a more adequate end-point than the scoring advanced cancers and distant metastases
Differential radio-sensitivities of human chromosomes 1 and 2 in one donor in interphase- and metaphase-spreads after 60Co Ī³-irradiation
Chromatin organization revealed by nanostructure of irradiation induced gamma H2AX, 53BP1 and Rad51 foci
The spatial distribution of DSB repair factors gamma H2AX, 53BP1 and Rad51 in ionizing radiation induced foci (IRIF) in HeLa cells using super resolution STED nanoscopy after low and high linear energy transfer (LET) irradiation was investigated. 53BP1 and gamma H2AX form IRIF with same mean size of (540 +/- 40) nm after high LET irradiation while the size after low LET irradiation is significantly smaller. The IRIF of both repair factors show nanostructures with partial anti-correlation. These structures are related to domains formed within the chromatin territories marked by gamma H2AX while 53BP1 is mainly situated in the perichromatin region. The nanostructures have a mean size of (129 +/- 6) nm and are found to be irrespective of the applied LET and the labelled damage marker. In contrast, Rad51 shows no nanostructure and a mean size of (143 +/- 13) nm independent of LET. Although Rad51 is surrounded by 53BP1 it strongly anti-correlates meaning an exclusion of 53BP1 next to DSB when decision for homologous DSB repair happened
Potent cytotoxic effects of Calomeria amaranthoides on ovarian cancers
<p>Abstract</p> <p>Background</p> <p>Ovarian cancer remains the leading cause of death from gynaecological malignancy. More than 60% of the patients are presenting the disease in stage III or IV. In spite of combination of chemotherapy and surgery the prognosis stays poor for therapy regimen.</p> <p>Methods</p> <p>The leaves of a plant endemic to Australia, <it>Calomeria amaranthoides</it>, were extracted and then fractionated by column chromatography. <it>In vitro </it>cytotoxicity tests were performed with fractions of the plant extract and later with an isolated compound on ovarian cancer cell lines, as well as normal fibroblasts at concentrations of 1-100 Ī¼g/mL (crude extract) and 1-10 Ī¼g/mL (compound). Cytotoxicity was measured after 24, 48 and 72 hours by using a non-fluorescent substrate, Alamar blue.</p> <p><it>In vivo </it>cytotoxicity was tested on ascites, developed in the abdomen of nude mice after inoculation with human OVCAR<sub>3 </sub>cells intraperitoneally. The rate of change in abdomen size for the mice was determined by linear regression and statistically evaluated for significance by the unpaired t test.</p> <p>Results</p> <p>Two compounds were isolated by chromatographic fractionation and identified by <sup>1</sup>H-NMR, <sup>13</sup>C-NMR and mass spectrometry analyses, EPD, an Ī±-methylene sesquiterpene lactone of the eremophilanolide subtype, and EPA, an Ī±-methylene carboxylic acid.</p> <p>Cytotoxicity of EPD for normal fibroblasts at all time points IC<sub>50 </sub>was greater than 10 Ī¼g/mL, whereas, for OVCAR<sub>3 </sub>cells at 48 hours IC<sub>50 </sub>was 5.3 Ī¼g/mL (95% confidence interval 4.3 to 6.5 Ī¼g/mL).</p> <p>Both, the crude plant extract as well as EPD killed the cancer cells at a final concentration of 10 Ī¼g/mL and 5 Ī¼g/mL respectively, while in normal cells only 20% cell killing effect was observed. EPA had no cytotoxic effects.</p> <p>Changes in abdomen size for control versus Cisplatin treated mice were significantly different, P = 0.023, as were control versus EPD treated mice, P = 0.025, whereas, EPD versus Cisplatin treated mice were not significantly different, P = 0.13.</p> <p>Conclusions</p> <p>For the first time both crude plant extract from <it>Calomeria amaranthoides </it>and EPD have been shown to have potent anti-cancer effects against ovarian cancer.</p
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