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Reducing the environmental burden and assessing the safety of plastics are huge global challenges. However, standard test data on the ready biodegradability of plastics are limited. We evaluated the ready biodegradability of 8 biodegradable plastics using Organisation for Economic Co-operation and Development (OECD) test guideline 301F with nonspecific bacteria and examined the effects of prolonging the test duration to a maximum of 90 d. Cellulose used as a potential reference material for plastics was not comparable to the reference material of OECD test guideline 301, but it may be improved by using a test concentration lower than the typical test concentration (100 mg/L). Of the 8 plastics examined, polyamide 4, poly(3-hydroxybutyrate-co-3-hydroxyhexanoate), polycaprolactone, and poly(butylene succinate adipate; PBSA) were biodegraded by >60% by day 28 and considered to show ready biodegradability. Poly(3-hydroxybutyrate; PHB), poly(3-hydroxybutyric acid-co-3-hydroxyvaleric acid; PHBV), and poly(butylene succinate; PBS) were biodegraded but did not fulfill the ready biodegradability criteria. Because the typical test concentration is considered to have negative effects on biodegradation and calculation of biodegradation percentage, using a lower concentration may result in PHB, PHBV, and PBS fulfilling the ready biodegradability criteria. Poly(d,l-lactide; PLA) was not biodegraded. The biodegradation of PBS and PBSA was noted to vary depending on the used inoculum and/or particle size. For the 7 plastics except PLA, the percentage biodegradation on day 60 was larger than that on day 28, indicating that a longer test period could be useful for evaluating the environmental persistence of plastics. In tests in which the plastics were not biodegraded by day 60, no marked biodegradation was observed by day 90. Environ Toxicol Chem 2021;40:2443-2449. © 2021 SETAC.

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Severe stomatitis may lead to the need to interrupt or discontinue cancer therapy and, thus, may affect control of the primary disease. Stomatitis may also increase the risk of local and systemic infection and significantly affects the quality of life and the cost of care. The present study was conducted to evaluate the efficacy of two traditional herbal medicines in controlling treatment-induced stomatitis in a small cohort of lung cancer patients treated with afatinib. All patients who were treated with afatinib for epidermal growth factor receptor (EGFR) mutated nonsmallcell lung cancer (NSCLC) between January, 2015 and March, 2016, were included in this study. During the study period, a total of 14 NSCLC patients were treated with afatinib, an EGFR-tyrosine kinase inhibitor (TKI). Two patients already had stomatitis at the time of initiation of afatinib therapy; among the remaining 12 NSCLC patients, 2 (16.7%) developed stomatitis. All the lesions in the 4 patients who developed stomatitis were completely alleviated after 2 weeks of therapy with Aznol mouthwash, a chamomile extract with anti-inflammatory effects, and Hangeshashinto, a traditional herbal (Kampo) medicine. Afatinib therapy was re-initiated, but none of the patients developed stomatitis thereafter. To the best of our knowledge, this is the first report evaluating oral care and management of stomatitis. This type of care and treatment may reduce the incidence of complications associated with EGFR-TKI therapy.

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We developed a detection method that uses quantitative real-time PCR (qPCR) and the TaqMan system to easily and rapidly assess the population of aniline-degrading bacteria in activated sludge prior to conducting a biodegradability test on a chemical compound. A primer and probe set for qPCR was designed by a multiple alignment of conserved amino acid sequences encoding the large (α) subunit of aniline dioxygenase. PCR amplification tests showed that the designed primer and probe set targeted aniline-degrading strains such as Acidovorax sp., Gordonia sp., Rhodococcus sp., and Pseudomonas putida, thereby suggesting that the developed method can detect a wide variety of aniline-degrading bacteria. There was a strong correlation between the relative copy number of the α-aniline dioxygenase gene in activated sludge obtained with the developed qPCR method and the number of aniline-degrading bacteria measured by the Most Probable Number method, which is the conventional method, and a good correlation with the lag time of the BOD curve for aniline degradation produced by the biodegradability test in activated sludge samples collected from eight different wastewater treatment plants in Japan. The developed method will be valuable for the rapid and accurate evaluation of the activity of inocula prior to conducting a ready biodegradability test.

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We have found that an HIV-1 accessory gene product Vpr enhanced HIV-1 reproduction in U1 cells chiefly by the induction of TNF, a proinflammatory cytokine, which was also known to be an activator of HIV-1 reproduction. We have generated the functional HIV-1 accessory gene product Vpr in bacterial cells. Vpr was generated in an Escherichia coli system (rVpr), purified with antibodies (Ab) to the 16 C-terminal amino acids of Vpr. The purified rVpr of 15 kDa was examined for its ability to upregulate HIV-1 reproduction in U1 cells, which is a reported function of the authentic Vpr. rVpr upregulated HIV-1 reproduction in U1 cells in a dose-dependent manner and induced the secretion of TNF. The upregulation of HIV-1 by rVpr was completely inhibited not only by anti-Vpr antibodies but also by anti-TNF antibody. These findings suggested that Vpr caused an HIV-1 reproduction in U1 cells through the induction of TNF.

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In transcriptional regulation, RNA polymerase II (pol II) interacts and forms complexes with a number of protein factors. To isolate and identify the pol II-associated proteins, we constructed a Schizosaccharomyces pombe strain carrying a FLAG tag sequence fused to the rpb3 gene encoding the pol II subunit Rpb3. By immunoaffinity purification with anti-FLAG antibody-resin, a pol II complex containing the Rpb1 subunit with a nonphosphorylated carboxyl-terminal domain (CTD) was isolated. In addition to the pol II subunits, the complex was found to contain three subunits of a transcription factor TFIIF (TFIIF alpha, TFIIF beta, and Tfg3) and TFIIF-interacting CTD-phosphatase Fcp1. The same type of pol II complex could also be purified from an Fcp1-tagged strain. The isolated Fcp1 showed CTD-phosphatase activity in vitro. The fcp1 gene is essential for cell viability. Fcp1 and pol II interacted directly in vitro. Furthermore, by chemical cross-linking, glutathione S-transferase pulldown, and affinity chromatography, the Fcp1-interacting subunit of pol II was identified as Rpb4, which plays regulatory roles in transcription. We also constructed an S. pombe thiamine-dependent rpb4 shut-off system. On repression of rpb4 expression, the cell produced more of the nonphosphorylated form of Rpb1, but the pol II complex isolated with the anti-FLAG antibody contained less Fcp1 and more of the phosphorylated form of Rpb1 with a concomitant reduction in Rpb4. This result indicates the importance of Fcp1-Rpb4 interaction for formation of the Fcp1/TFIIF/pol II complex in vivo.

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