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Plasmodium parasites cause Malaria disease, which remains a significant threat to global health, affecting 200 million people and causing 400,000 deaths yearly. Plasmodium falciparum and Plasmodium vivax remain the two main malaria species affecting humans. Identifying the malaria disease in blood smears requires years of expertise, even for highly trained specialists. Literature studies have been coping with the automatic identification and classification of malaria. However, several points must be addressed and investigated so these automatic methods can be used clinically in a Computer-aided Diagnosis (CAD) scenario. In this work, we assess the transfer learning approach by using well-known pre-trained deep learning architectures. We considered a database with 6222 Region of Interest (ROI), of which 6002 are from the Broad Bioimage Benchmark Collection (BBBC), and 220 were acquired locally by us at Fundação Oswaldo Cruz (FIOCRUZ) in Porto Velho Velho, Rondônia-Brazil, which is part of the legal Amazon. We exhaustively cross-validated the dataset using 100 distinct partitions with 80% train and 20% test for each considering circular ROIs (rough segmentation). Our experimental results show that DenseNet201 has a potential to identify Plasmodium parasites in ROIs (infected or uninfected) of microscopic images, achieving 99.41% AUC with a fast processing time. We further validated our results, showing that DenseNet201 was significantly better (99% confidence interval) than the other networks considered in the experiment. Our results support claiming that transfer learning with texture features potentially differentiates subjects with malaria, spotting those with Plasmodium even in Leukocytes images, which is a challenge. In Future work, we intend scale our approach by adding more data and developing a friendly user interface for CAD use. We aim at aiding the worldwide population and our local natives living nearby the legal Amazon's rivers.

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Parasites are ubiquitous in wildlife populations and have a profound impact on population dynamics. Interest in parasites of wildlife has increased significantly in recent years, particularly in those with relevant conservation status. Patagonia is one of the wildest and remote areas of the world. The Wolffsohn's viscacha lives in a small mountainous area of Patagonia. Until now, little is known about the biology and ecology of this species. The aim of this research was to study the gastrointestinal parasite diversity in this rodent from a coprological survey. A total of 125 fecal samples from 25 colonies were examined. Each sample was rehydrated, homogenized, and analyzed using three parasitological techniques: spontaneous sedimentation, Mini-FLOTAC, and centrifugation-flotation in sucrose-saturated solution, followed by examination under optical microscopy. The samples, eggs, and oocysts of parasites were described, measured, and photographed. All colonies were positive for at least one parasite species. A total of 10 parasitic species were identified: Viscachataenia sp., possibly V. quadrata, Monoecocestus sp., an unidentified anoplocephalid, Heteroxynema sp., possibly H. (Cavioxyura) viscaciae, Helminthoxys sp., possibly H. effilatus, an unidentified strongylid-type egg, Trichuris sp., two morphologies of unidentified coccidians and Eimeria sp. This is the first exhaustive study of gastrointestinal parasites in L. wolffsohni and a large number of eggs and oocysts of parasites were found. Our results highlight the use of noninvasive techniques for the study of parasites of wildlife hosts; as in the case of this rodent with a remote habitat, which makes sampling difficult. The results of our study provide baseline information on gastrointestinal parasite infections in this species.

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OBJECTIVE: This scoping review aimed to identify and describe the available evidence on the effect of magnifying devices (loupe or microscope) on the performance of restorative dental preparations. MATERIALS AND METHODS: This study was conducted according to the PRISMA-ScR guidelines for scoping reviews and registered on the INPLASY database. An electronic search was performed in four databases and Grey literature for articles published until November 2023. Eligibility criteria were determined using the PICOS strategy and comprised studies that evaluated the performance of magnification devices for restorative dental preparations. A bibliographic mapping of the evidence was conducted. RESULTS: Sixteen studies met the inclusion criteria. Most of the studies (n = 12) compared the performance of dental preparations using magnification loupes vs. no magnification. The magnification for loupes and microscopes ranged from 2.5x to 4.0x and 6.4x to 10x, respectively. The use of magnifying loupes improved the performance of restorative preparations in 66.6% of the evaluated studies. However, when the magnifications were compared, the greater magnification provided by microscopes did not improve preparation performance compared to magnification loupes. Regarding the place of publication, the American continent concentrates the most significant number of evidence. CONCLUSIONS: Although evidence for magnification improving the performance of dental preparations has increased over the last decade, basically only in vitro studies (most of which have taken place in the Americas) have been reported in the literature. The evidence suggests that magnification significantly improves restorative preparation performance when compared to non-magnification. However, higher magnifications (e.g., microscopes) do not appear to improve tooth preparation performance compared with lower magnification devices (e.g., magnification loupes). CLINICAL RELEVANCE: Available evidence supports that using magnification can improve the performance of restored tooth preparations. However, high magnifications have no advantages over lower magnifications.

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SUMMARY: Etoposide is an effective antimitotic and antineoplastic agent used to treat various human malignancies. In the present study, Etoposide was injected intraperitoneally into the rats at 1 mg/kg/day for 52 days (52 doses). The control animals received physiological saline (0.5 ml) intraperitoneally daily for 52 doses. The body weight of etoposide-treated rats was significantly reduced compared to control rats. Lipid peroxidation demonstrated an insignificant rise in hepatic tissue, a non-significant decline in renal tissue, and a significant reduction in cardiac tissue. The levels of GSH in hepatic and renal tissue were found to be non-significantly increased but significantly increased in cardiac tissue compared to controls. GR activity was found to be considerably decreased in the treated group. G-S-T levels increased significantly in all treated group. Etoposide injections caused a non-significant change in the GPX level of hepatic tissue, whereas renal and cardiac tissues showed a significant increase. The activity of CAT in hepatic tissue was significantly increased, while CAT activity in renal tissue showed a non-significant decrease, whereas in cardiac tissue, significantly lower levels were observed than in control group. The level of CYTp450 in hepatic and cardiac tissues showed a significant increase; however, renal tissue showed non-significant depletion, whereas CYTb5 in hepatic, renal, and cardiac tissues was significantly lower than controls. The protein content in the hepatic tissue was not significantly increased, whereas the total protein in the renal and cardiac tissues was increased significantly. The research finding is indicative of detoxification activity in the etoposide model.

El etopósido es un agente antimitótico y antineoplásico eficaz que se utiliza para tratar diversas neoplasias malignas humanas. En el presente estudio, se inyectó etopósido por vía intraperitoneal a las ratas a razón de 1 mg/kg/día durante 52 días (52 dosis). Los animales control recibieron solución salina fisiológica (0,5 ml) por vía intraperitoneal diariamente por 52 dosis. El peso corporal de las ratas tratadas con etopósido se redujo significativamente en comparación con las ratas del grupo control. La peroxidación lipídica demostró un aumento insignificante del tejido hepático, una disminución no significativa del tejido renal y una reducción significativa del tejido cardíaco. Se encontró que los niveles de GSH en el tejido hepático y renal no aumentaron significativamente, pero sí aumentaron significativamente en el tejido cardíaco en comparación con los controles. Se encontró que la actividad de GR disminuyó considerablemente en el grupo tratado. Los niveles de G-S-T aumentaron significativamente en todos los grupos tratados. Las inyecciones de etopósido provocaron un cambio no significativo en el nivel de GPX del tejido hepático, mientras que los tejidos renal y cardíaco mostraron un aumento significativo. La actividad de CAT en el tejido hepático aumentó significativamente, mientras que la actividad de CAT en el tejido renal mostró una disminución no significativa, mientras que en el tejido cardíaco se observaron niveles significativamente más bajos que en el grupo de control. El nivel de CYTp450 en los tejidos hepático y cardíaco mostró un aumento significativo; sin embargo, el tejido renal mostró un agotamiento no significativo, mientras que CYTb5 en los tejidos hepático, renal y cardíaco fue significativamente menor que los controles. El contenido de proteínas en el tejido hepático no aumentó significativamente, mientras que la proteína total en los tejidos renal y cardíaco aumentó significativamente. El hallazgo de la investigación es indicativo de la actividad de desintoxicación en el modelo de etopósido.

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During an epidemiological survey, a potential novel species within the basidiomycetous yeast genus Trichosporon was observed. The clinical strain was obtained from a urine sample taken from a Brazilian kidney transplant recipient. The strain was molecularly identified using the intergenic spacer (IGS1) ribosomal DNA locus and a subsequent phylogenetic analysis showed that multiple strains that were previously reported by other studies shared an identical IGS1-genotype most closely related to that of Trichosporon inkin. However, none of these studies provided an in-depth characterization of the involved strains to describe it as a new taxon. Here, we present the novel clinically relevant yeast for which we propose the name Trichosporon austroamericanum sp. nov. (holotype CBS H-24937). T. austroamericanum can be distinguished from other siblings in the genus Trichosporon using morphological, physiological, and phylogenetic characters.

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PURPOSE: To evaluate the use of the latest generation smartphone camera in performing arterial microanastomosis in rats. METHODS: Ten Wistar rats were divided into 2 groups and underwent anastomosis of the right carotid artery with the aid of magnification from a microscope (group M) and a smartphone camera (group S), to compare patency in 72 hours, as well as to measure the weight of the animals, diameter of the carotid arteries and anastomosis time. RESULTS: There was no statistical difference between the weight of the animals or the diameter of the carotid arteries. There was a statistical difference for the time spent on anastomoses, which was greater in group S, with higher rates of thrombosis (p < 0.05). CONCLUSIONS: Although our patency and anastomosis time results were statistically lower in the smartphone group, there was success in some cases. As the segment continues to progress, it is likely that the results will improve in line with the evolution of camera technology.

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Aleurites moluccanus (candlenut) and Bertholletia excelsa (Brazil nut) are marketed as dietary supplements for weight loss. These dietary supplements have been found to sometimes be adulterated with toxic nuts/seeds from Cascabela thevetia, commonly known as yellow oleander or lucky nut. This study emphasizes the key identification parameters to differentiate the genuine and adulterated nuts. Samples were obtained from authenticated sources of the nuts and from commercial sources of dietary supplements. This study examined 38 samples, including voucher and commercial samples. All eight commercial candlenut dietary supplement samples were adulterated. Additionally, two samples sold as Brazil nuts were also found to be adulterated. Other nuts were screened for the presence of Cardiac Glycosides, but none were found to be positive. The presence of yellow oleander was confirmed in all commercial dietary supplement samples marketed as candlenut as well as in commercial samples of Brazil nut. This study provides simple key identification characters using micro-morphology and histochemical localization of cardiac glycosides in the commercial nuts, HPTLC fingerprints, and LC-DAD-Q-ToF analytical parameters to detect and identify adulteration in commercial products.

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This article describes detailed and novel data on the anatomy and histochemistry of leaves, stems, and roots of Camonea umbellata (L.) A.R.Simões & Staples in different environments for the identification of characters with taxonomical value and of ecological importance, with provision of light and scanning electron microscopy images. To analyze the characters, we collected samples of the vegetative organs of three individuals in each of three populations, which were in a grazing area, an urban environment, and a biological reserve. The main diagnostic anatomical markers for the identification of C. umbellata include amphistomatic leaves, tetracytic and brachyparatetracytic stomata, peltate trichomes, long simple trichomes, epidermis with striated cuticle ornamentation, mesophyll with acute borders, presence of druses, secretory channels, angular collenchyma, fibrous pericycle in the stem, intraxylary phloem in the vegetative organs, oil bodies throughout the midrib, petiole, stem and root, and epicuticular waxes of the crust and coiled rodlet types. Since the characters above did not show variation in the environments evaluated, we consider these characters taxonomically useful for the identification of C. umbellata. RESEARCH HIGHLIGHTS: The anatomy of the aerial vegetative organs of Camonnea umbellata retains common Convolvulaceae characters. The sinuosity of the epidermal cell walls and the density of trichomes in the epidermis of the petiole were visually variable characters among the analyzed individuals. Amphistomatic leaves, tetracytic and brachyparatetracytic stomata, peltate trichomes, epidermis with striated cuticle ornamentation, dorsiventral mesophyll with border acute, presence of druses, secretory structures, angular collenchyma, fibrous pericycle in the stem, intraxillary phloem, presence of oil bodies in all organs, and epicuticular waxes of the crust type and coiled rods were considered important anatomical markers for the recognition and correct identification of Camonea umbellata.

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Microscopy is integral to medical research, facilitating the exploration of various biological questions, notably cell quantification. However, this process's time-consuming and error-prone nature, attributed to human intervention or automated methods usually applied to fluorescent images, presents challenges. In response, machine learning algorithms have been integrated into microscopy, automating tasks and constructing predictive models from vast datasets. These models adeptly learn representations for object detection, image segmentation, and target classification. An advantageous strategy involves utilizing unstained images, preserving cell integrity and enabling morphology-based classification-something hindered when fluorescent markers are used. The aim is to introduce a model proficient in classifying distinct cell lineages in digital contrast microscopy images. Additionally, the goal is to create a predictive model identifying lineage and determining optimal quantification of cell numbers. Employing a CNN machine learning algorithm, a classification model predicting cellular lineage achieved a remarkable accuracy of 93%, with ROC curve results nearing 1.0, showcasing robust performance. However, some lineages, namely SH-SY5Y (78%), HUH7_mayv (85%), and A549 (88%), exhibited slightly lower accuracies. These outcomes not only underscore the model's quality but also emphasize CNNs' potential in addressing the inherent complexities of microscopic images.

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In recent decades, many studies have been published on the use of automatic smear microscopy for diagnosing pulmonary tuberculosis (TB). Most of them deal with a preliminary step of the diagnosis, the bacilli detection, whereas sputum smear microscopy for diagnosis of pulmonary TB comprises detecting and reporting the number of bacilli found in at least 100 microscopic fields, according to the 5 grading scales (negative, scanty, 1+, 2+ and 3+) endorsed by the World Health Organization (WHO). Pulmonary TB diagnosis in bright-field smear microscopy, however, depends upon the attention of a trained and motivated technician, while the automated TB diagnosis requires little or no interpretation by a technician. As far as we know, this work proposes the first automatic method for pulmonary TB diagnosis in bright-field smear microscopy, according to the WHO recommendations. The proposed method comprises a semantic segmentation step, using a deep neural network, followed by a filtering step aiming to reduce the number of false positives (false bacilli): color and shape filtering. In semantic segmentation, different configurations of encoders are evaluated, using depth-wise separable convolution layers and channel attention mechanism. The proposed method was evaluated with a large, robust, and annotated image dataset designed for this purpose, consisting of 250 testing sets, 50 sets for each of the 5 TB diagnostic classes. The following performance metrics were obtained for automatic pulmonary TB diagnosis by smear microscopy: mean precision of 0.894, mean recall of 0.896, and mean F1-score of 0.895.

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