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101.
BackgroundKnown in the past for its toxic aspect as the main urban pollutant, in the last few decades, ozone has been gaining greater visibility for its possible antimicrobial, antiviral, and antioxidant effects when used in human dermatological pathologies. Despite the reports of clinical benefits, the standard dosage for clinical efficacy and safety are yet not clear, nor are its means of application and its true acting mechanism.ObjectiveWe conducted a review to determine the efficacy and safety of ozone therapy for a variety of dermatological conditions.MethodsWe considered clinical trials (both randomized and non-randomized) published between December 2020 and March 2021 as long as they provided some PICO information, i.e., population (P), intervention (I), and study design. The skin dermatological conditions researched were: acne, dermatitis, psoriasis, systemic sclerosis, herpes, aging, ulcers, and skin scarring.ResultsA total of 326 articles were identified and 150 remained after duplicates were removed. After titles, abstracts and full articles were read, 17 articles were included in the systematic review (with 643 patients). ConclusionOzone therapy seems promising for some dermatological conditions; however, the articles included in this review had methodological limitations and did not sufficiently demonstrate sound evidence for safe therapy. Therefore, more studies with better methodological standards and longer-term assessments of side effects should be conducted to achieve better standards and safety in ozone therapy for dermatological conditions.  相似文献   
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Titanium oxide (TiO2) has been widely investigated as a photocatalytic material, and the fact that its performance depends on its crystalline structure motivates further research on the relationship between preparation methods and material properties. In this work, TiO2 thin films were grown on non-functionalized wave-like patterned vertically aligned carbon nanotubes (w-VA-CNTs) via the atomic layer deposition (ALD) technique. Grazing incidence X-ray diffraction (GIXRD) analysis revealed that the structure of the TiO2/VA-CNT nanocomposites varied from amorphous to a crystalline phase with increasing deposition temperature, suggesting a “critical deposition temperature” for the anatase crystalline phase formation. On the other hand, scanning transmission electron microscopy (STEM) studies revealed that the non-functionalized carbon nanotubes were conformally and homogeneously coated with TiO2, forming a nanocomposite while preserving the morphology of the nanotubes. X-ray photoelectron spectroscopy (XPS) provided information about the surface chemistry and stoichiometry of TiO2. The photodegradation experiments under ultraviolet (UV) light on a model pollutant (Rhodamine B, RhB) revealed that the nanocomposite comprised of anatase crystalline TiO2 grown at 200 °C (11.2 nm thickness) presented the highest degradation efficiency viz 55% with an illumination time of 240 min. Furthermore, its recyclability was also demonstrated for multiple cycles, showing good recovery and potential for practical applications.

Amorphous or anatase crystalline TiO2/VA-CNT nanocomposites were grown controlling the synthesis temperature. Photocatalytic degradation of RhB of 55% was achieved after 240 min. The immobilized material remains active after 4 cycles of use.  相似文献   
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We wished to verify whether semen processing by discontinuous double-layered density gradient centrifugation could improve sperm apoptotic DNA fragmentation rates using a commercially available deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end labeling assay in 35 consecutive men presenting for assisted reproductive treatments. Although sperm motility did improve as expected, no effects were observed in sperm apoptotic DNA fragmentation rates, and this should be considered in the routine assisted reproduction setting.  相似文献   
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OBJECTIVE: Using a mouse embryo bioassay, we examined the embryotoxic properties of serum obtained from eight women who had ingested cocaine base paste (CBP) for a period of 1-3 years. STUDY DESIGN: Two-cell stage mouse embryos were cultured in the presence of serum extracted from eight CBP-smoking or control women. After 48h, embryos were evaluated to determine their developmental stage and then processed by Tarkoswki's technique to determine the proportion of embryos with micronuclei, in order to establish the number of micronuclei/embryo. RESULTS: Serum from CBP patients diminished the percentage of embryos progressing to the compacted morula stage, while increasing the proportion of embryos with micronuclei and the corresponding micronuclei/embryo ratio. CONCLUSION: These findings provide the first experimental evidence of embryotoxic compounds in the serum of CBP-smoking women. This study highlights the reproductive risk of chronically ingested CBP and demonstrates the need for further studies.  相似文献   
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