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Interaction of chicken heterophils and Eimeria tenella results in different phenotypes of heterophil extracellular traps (HETs)
Publication . Rentería-Solís, Zaida; Silva, Liliana M. R.; Grochow, Thomas; Zhang, Runhui; Nguyen-Ho-Bao, Tran; Daugschies, Arwid; Taubert, Anja; Conejeros, Iván; Hermosilla, Carlos
Chicken coccidiosis causes annual losses exceeding GBP 10 billion globally. The most pathogenic species for domestic fowls including Eimeria tenella, E. acervulina, and E. maxima, can lead to gastrointestinal issues ranging from mild to fatal. In this study, stages of E. tenella and freshly isolated chicken heterophils were co-cultured for 180 min. These interactions were analyzed using live 3D holotomographic and confocal microscopy. We observed that E. tenella stages were entrapped by heterophils and heterophil extracellular traps (HETs). Notably, different HET phenotypes, specifically sprHETs and aggHETs, were induced regardless of the stage. Furthermore, the quantification of extracellular DNA release from co-cultures of heterophils and sporozoites (ratio 1:1) for 180 min demonstrated a significantly higher release (p = 0.04) compared to negative controls. In conclusion, research on the chicken innate immune system, particularly fowl-derived HETs, remains limited. More detailed investigations are needed, such as exploring the time-dependent triggering of HETs, to establish a standard incubation time for this pathogen defense mechanism. This will enhance our understanding of its role in parasite survival or death during HET confrontation.
Insights into Candida colonization in intensive care unit patients : a prospective multicenter study
Publication . Nascimento, Teresa; Inácio, João; Guerreiro, Daniela; Patrício, Patrícia; Proença, Luís; Toscano, Cristina; Diaz, Priscila; Barroso, Helena
The skin mycobiota plays a significant role in infection risk, pathogen transmission, and personalized medicine approaches in intensive care settings. This prospective multicenter study aimed to enhance our understanding of intensive care units’ (ICUs’) Candida colonization dynamics, identify modifiable risk factors, and assess their impact on survival risk. Specimens were taken from 675, 203, and 110 patients at the admission (D1), 5th (D5), and 8th (D8) days of ICU stay, respectively. The patient’s demographic and clinical data were collected. Candida isolates were identified by conventional culture-based microbiology combined with molecular approaches. Overall, colonization was 184/675 (27.3%), 87/203 (42.8%), and 58/110 (52.7%) on D1, D5, and D8, respectively. Candida colonization dynamics were significantly associated with ICU type (odds ratio (OR) = 2.03, 95% CI 1.22–3.39, p = 0.007), respiratory infection (OR = 1.74, 95% CI 1.17–2.58, p = 0.006), hemodialysis (OR = 2.19, 95% CI 1.17–4.10, p = 0.014), COVID-19 (OR = 0.37, 95% CI 0.14–0.99, p = 0.048), and with a poor 3-month outcome (p = 0.008). Skin Candida spp. colonization can be an early warning tool to generate valuable insights into the epidemiology, risk factors, and survival rates of critically ill patients, and should be considered for epidemiological surveillance.
Influence of transducer pressure and examiner experience on muscle active shear modulus measured by shear wave elastography
Publication . Pimenta, R.; Coelho, F.; Correia, J. P.; Vaz, João R.
Introduction: This study examined the effects of ultrasound transducer pressure and examiner experience on the biceps femoris long head and semitendinosus muscle active shear modulus in healthy individuals (n = 28).
Methods: Active shear modulus was assessed using shear wave elastography at 20% of knee flexor maximal voluntary isometric contraction. Examiners with different experience levels measured the muscles' shear modulus with three pressure levels: mild, moderate, and hard.
Results: A main effect of transducer pressure was found for both biceps femoris long head (p < 0.001; η2p = 0.314) and semitendinosus muscles (p < 0.001; η2p = 0.280), whereas differences were found between mild-moderate (biceps femoris long head: p = 0.013, d = 0.23; semitendinosus: p = 0.024, d = 0.25), and mild-hard pressures (biceps femoris long head: p = 0.001, d = 0.47; semitendinosus: p = 0.002, d = 0.47). Examiners performed similar shear modulus measurements in the biceps femoris long head (p = 0.299; η2p = 0.041) and semitendinosus (p = 0.177; η2p = 0.066), although the experienced examiner showed a higher measurement repeatability (biceps femoris long head: ICC = 0.86–0.95, semitendinosus: ICC = 0.89–0.96; vs. biceps femoris long head: ICC = 0.78–0.87, semitendinosus: ICC = 0.66–0.87).
Conclusion: Transducer pressure influences the active shear modulus measurement between mild and moderate or hard pressures. Additionally, examiner experience seems to have no influence on muscle active shear modulus measurement when assessed at the same site (using casts).
Implications for practice: Future studies assessing active muscle shear modulus should use mild transducer pressure and having experienced examiners in order to improve measurement reliability.
In vitro studies into establishing therapeutic bioequivalence of complex topical products : weight of evidence
Publication . Miranda, Margarida; Volmer, Zoe; Cornick, Alicia; Goody, Aidan; Cardoso, Catarina; Pais, Alberto A.C.C.; Brown, Marc; Vitorino, Carla
Over the past decade, topically applied drug products have experienced extraordinary price increases, due to the shortage of multisource generic drug products. This occurrence is mainly related to the underlying challenges evolved in topical bioequivalence documentation. Although there has been continuing regulatory efforts to present surrogate in vitro methods to clinical endpoint studies, there is still a continued need for cost- and time-efficient alternatives that account for product specificities. Hence, this work intended to expose bioequivalence assessment issues for complex topical formulations, and more specifically those related with product efficacy guidance. As a model drug and product, a bifonazole 10 mg/g cream formulation was selected and two different batches of the commercially available Reference Product (RP) were used: RP1 that displayed lower viscosity and RP4 which presented high, but not the highest, viscosity. In vitro human skin permeation testing (IVPT) was carried out and the results were evaluated by means of the traditional bioequivalence assessment approach proposed by the EMA, as well as by the Scaled Average Bioequivalence assessment approach proposed by the FDA. Based on previous experience, there was an expectation of a high level of variability in the results, thus alternative methods to evaluate local drug skin availability were developed. More specifically, an infected skin disease model, where ex vivo human skin was infected and ATP levels were used as a biological marker for monitoring antifungal activity after product application. The results showed that permeation equivalence could not be supported between the different RP batches. In contrast, this statistical difference between the formulation batches was not indicated in the disease model. Nevertheless, in pivotal IVPT studies, the lowest permeant formulation (RP4) evidenced a higher antifungal in vitro activity as reported by the lower levels of ATP. A critical appraisal of the results is likewise presented, focusing on an outlook of the real applicability of the regulatory guidances on this subject.
In vitro research methods used to evaluate shaping ability of rotary endodontic files : a literature review
Publication . Elemam, Ranya F.; Azul, Ana Mano; Dias, João; Sahli, Khaled El; Leonardo, Renato de Toledo
Background/Objectives: In this article, we present a literature review of methods used to measure the shaping ability of endodontic rotary files, including the selection of endodontic sample type (extracted teeth versus simulated blocks) and an imaging evaluation method. This review was conducted as background research to identify concerns that arise when designing research studies in this domain and propose how the field can plan more systematic studies going forward. Methods: A literature search was conducted using PubMed, MEDLINE, Embase, ScienceDirect, Scopus, and e B-on databases, including studies published in English from January 2010 to June 2024. Only studies that specified in vitro or ex vivo methods for evaluating the endodontic performance of NiTi rotary files on canal transportation and centering ability were considered. Results: A total of 86 studies met the inclusion criteria from an initial pool of 651. Of these, 67 studies used extracted teeth, while 20 utilized simulated root canals in resin blocks. For evaluation methods, 55 studies employed Micro-Computed Tomography and Cone-Beam Computed Tomography (MCT + CBCT), 30 used Double Digital Images/Radiographs/Photographs (DDIR + DDIP) with software analysis, 1 used both DDIR and MCT, 1 used high-precision nano-CT, and 1 used a digital single-lens reflex (DSLR) camera. Conclusions: The findings indicate that the MCT method and its advanced variations appear superior in many cases for evaluating the quality of root canal instrumentation due to their ability to provide detailed three-dimensional images. We also discuss the pros and cons of other evaluation methods, including CBCT and DDIR. Finally, we identify important factors to consider for optimizing future cross-study comparisons. This work highlights the importance of being familiar with shaping ability assessment methods as new instruments are introduced to the market.