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The current study was conducted to statistically compare the SYBR® Green quantitative polymerase chain reaction (qPCR) assay and the conventional plate counting (PC) method to construct growth curves of a cocktail of Weissella viridescens in pure culture under different isothermal storage conditions (4, 8, 14, and 30 °C) and in mixed culture with Leuconostoc mesenteroides at 8 °C. The efficiency and specificity of the qPCR standard curves were confirmed, and both methods were adequate to quantify the growth kinetics of W. viridescens at all isothermal temperatures, demonstrating a good correlation and agreement. The efficiencies of the standard curves varied between 98% and 102%. The SYBR® Green qPCR assay was also able to differentiate the growth curves of W. viridescens and L. mesenteroides in the mixed culture at 8 °C. Additionally, the SYBR® Green qPCR method was considered a faster and more sensitive alternative to construct growth curves under different isothermal conditions and differentiate morphologically similar lactic acid bacteria. Overall, the results suggest that the SYBR® Green qPCR method is a reliable and efficient tool to study microbial growth kinetics in pure and mixed cultures., Competing Interests: Declaration of competing interest The authors declare that they have no financial or non-financial interests that could be perceived as potential conflicts of interest regarding this research. None of the authors have received any form of compensation, including honoraria or consultancy fees, from any organization that may gain or lose financially from the publication of this manuscript. The authors have no financial or personal relationships that could bias this work or create a potential conflict of interest., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Aquatic ecosystems provide habitats for many organisms. Historically, riverbanks have always been inhabited and exploited for subsistence and navigation. The present study evaluates the contamination and ecological risks caused by potentially toxic elements in surface sediments of the Paraguaçu River, Bahia, Brazil. Seven sediments samples were collected, and eight heavy metals were determined employing inductively coupled plasma spectrometry mass (ICP-MS). The concentrations range as (mg kg -1 ) found were 6.78-18.68 for lead, 14.21-42.16 for zinc, 27.61-48.63 for nickel, 2.03-6.50 for chromium, 6.06-12.90 for vanadium, 5.99-13.33 for cupper, 1.25-3.19 for cobalt, and 79.52-286.08 for manganese. Nickel showed significant enrichment (EF: 5.75; 7.62, and 14.11), followed by zinc, which showed moderate enrichment (EF: 2.16; 2.19, and 4.52). These enrichment levels are possible of anthropogenic origin. When the pollution index (PI) was evaluated, the elements V, Ni, Zn, Mn, Co, and Cu were strongly polluted (PI ≥3). In general, the pollution index (PI), geoaccumulation index (I geo ), enrichment factor (EF), and potential ecological risk indices (E r and PERI) show that contaminated sediments have adverse effects on aquatic environments, especially for o Mn, Ni, Pb, V, and Zn., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Background: Acquisition of surgical instruments (SI) and implants by loaner system is a worldwide practice. Although quality of device reprocessing has been reported to be lower in low and middle-income countries compared with higher income countries, few investigations have been conducted on the management and reprocessing of loaned devices. Thus, in this study we evaluate the practices of management and reprocessing of loaner SI and non-sterile implants (NSI) in a high (Australia) and a middle-income (Brazil) country., Methods: Cross-sectional surveys (hardcopy or online form) was self-administered by sterilising service unit's personnel of Brazilian and Australian hospitals. Only those units that sourced orthopaedic surgical instruments and non-sterile loaned implants from independent companies were eligible., Results: A total of 65 questionnaires from Australia and 168 from Brazil were analysed. Quality indicators regarding structure and work process for the management and reprocessing of loaned SI and NSI was of a higher standard in Australia than in Brazil. However, failures were detected in both countries, for instance delivery delays and improper point-of-use pre-cleaning practices., Conclusion: There are key challenges inherent of the multifaceted reusable medical devices loaner system in both countries, such as communication failures, implementation of non-recommended practices, reprocessing of NSI, and other related to structure and process quality indicators, that must be faced. Initial and ongoing education and training should be provided and should embrace the themes of technical proficiency, effective communication and teamwork, and should include all personnel involved in this process, even loaner company staff., Competing Interests: Conflict of interest None., (Copyright © 2021 Australasian College for Infection Prevention and Control. Published by Elsevier B.V. All rights reserved.)

Rhipicephalus sanguineus sensu lato (s.l.), commonly known as brown dog tick, is a widely distributed tick species that is substantially important for human and veterinary medicine. Therefore, it is the target of different control methods. Carvacrol and its semisynthetic derivative, acetylcarvacrol, are promising chemical compounds for alternative tick control. Thus, this study aimed to compare the repellent activities of carvacrol and acetylcarvacrol at different concentrations and drying times. Additionally, morphological alterations found in salivary glands were evaluated through histological techniques after exposure to acetylcarvacrol. The impact of the morphological changes on the development and survival of acini/cells in salivary glands was measured by a semiquantitative analysis. The repellent action of both compounds did not differ when evaluated at different concentrations, although acetylcarvacrol increased its effects as the concentration raised. Regarding the different drying times, acetylcarvacrol maintained its effects after 3 hours of exposure, while the efficacy of carvacrol decreased during this time period. Salivary glands of unfed R. sanguineus s.l. females showed dose-dependent alterations in the size and shape of acini as well as cytoplasmic vacuolization. Loss of the acinar cell limit, rupture of secretory granules and nuclear changes in the cells were also observed in the treated groups. Thus, our results demonstrated the potential of acetylcarvacrol to act as repellent against R. sanguineus s.l. Additionally, the morphological alterations found in salivary glands may interfere with the feeding process of ticks, which contributes to mitigate infestation by this species., (Copyright © 2021. Published by Elsevier GmbH.)

The northern and northeastern portion of the Todos os Santos Bay (TSB) is known for the presence of an oil refinery in addition to the development of other activities with significant potential for impact on the environment. 30 samples of superficial mangrove sediment were collected in two different locations: on the banks of the São Paulo River near the Landulpho Alves Mataripe Refinery (RLAM) and at Caboto Beach, a place that was once a control point in studies of metal pollution. After the determination of potentially toxic elements (Al, As, Cd, Cr, Cu, Fe, Mn, Ni, Pb, Ti, V, Zn), the quality of the sediment was evaluated using the concentrations of these elements associated with geochemical parameters (TOC, P, S, and granulometry). In this way, the pollution indexes (EF, I geo , P N ) were calculated in addition to the comparison with the guide values for the sediment quality (TEL, PEL, ERL, ERM). Among the elements analyzed, Cu also showed levels (92.71-97.54 mg kg -1 ) very close to PEL (108 mg kg -1 ). At 13 sampling points, Cr concentrations were higher (56.16-66.01 mg kg -1 ) than TEL (52.3 mg kg -1 ). Ba showed significant concentrations in 6 samples collected on the São Paulo River, a region close to the oil refining area. The enrichment factor (EF) showed that most elements did not show enrichment, except for Zn. Through Igeo there was a tendency towards serious pollution of Ba, Cu, and Zn; moderately polluted by Cr. Principal component analysis (PCA) and Spearman's classification showed a correlation greater than 70% between the variables. According to Nemerow Synthetic Pollution (P N ), both areas are polluted by Al, Ba, Cr, Cu, Fe, Mn, Ni, Ti, V, and Zn., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

The clinical manifestations most frequently observed in cats with leishmaniasis caused by Leishmania infantum are cutaneous alterations, which suggest a high parasitic load in the skin and the possibility of infecting a vector. This study evaluated the infectiousness of to phlebotomine sand flies cats infected with L. infantum. A total of 12 cats with infection by L. infantum from the city of Teresina, Piauí, Brazil, were included in the study. Cats were diagnosed by direct visualization of the parasite. Laboratory-bred insects, free from infection by Leishmania spp. were offered a blood meal for 60 min on cats infected with L. infantum. On the fifth and sixth day after the blood meal, flies were dissected to assess promastigote forms of the parasite in the digestive system. Eight cats (67 %) were able to infect the vectors. The frequency of infected insects per cat ranged 0.0-94.4%. The mean frequency of insects feeding on cats was 95.2 %. Large numbers of the parasite were observed per insect, but were not quantified. The result confirm that cats are able to infect L. longipalpis, indicating that cats are part of the epidemiological chain of VL, acting as reservoir of the disease., Competing Interests: Declaration of Competing Interest No competing interests to declare., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Background: The acquisition of reusable surgical instruments (RSIs) through loaner system is a worldwide phenomenon, particularly in orthopaedic surgeries. Loaner sets contain high-complex design RSIs, which are very difficult to clean, and also include single use implants, such as screws, that remain in the surgical tray and are subjected to multiple reprocessing until they are implanted. Inadequate cleaning of SI and various exposures of single-use implants to physical, chemical and biological agents can compromise their quality/safety and promote biofilm formation. The difficulty in cleaning is compounded in middle and low-income countries where automated cleaning infrastructure at sterilizing service units is often unavailable, and thus manual cleaning only is performed. Thus, we aimed to determine the condition of orthopaedic loaned sets when delivered to the hospital, assess the quality of complex-design RSIs reprocessed by manual cleaning, and evaluate the effect of multiple reprocessing on single-use implant (screw)., Methods: Flexible medullary reamers (FMRs), depth gauges and screws used for femur intramedullary nailing, in clinical use for >1 year, were obtained from three Brazilian loaner companies and assessed for residual ATP, protein, bacterial contamination, endotoxin and/or biofilm at delivery at the hospital, following cleaning and steam sterilisation., Results: Before cleaning, blood was visible on a RSIs tray, and RSIs/screws were contaminated with high amounts of ATP, protein and bacteria. Visible soil was released during brushing of a FMR lumen and, following cleaning, the inner layer of 34/40 were visible soiled, and over 5/8 were protein test positive. Following sterilisation, biofilm and soil, including fragments appearing to be bone, were detected by scanning electron microscopy on RSIs/screws. A sterilised FMR revealed visible soil on the inner layer. Endotoxin tests were negative., Conclusion: The contaminated condition of loaned-complex-designed RSIs/screws upon arrival at the hospital and after reprocessing points to the insufficiency of manual reprocessing and management practices related to this instruments/implants. A multidisciplinary approach involving expert in design/manufacture, regulating, managing, reprocessing and surgeons is suggested to improve RSIs manufacture that enables complete decontamination and maintain the surgical patient safety., (Copyright © 2018 Elsevier Ltd. All rights reserved.)