Siderite and vivianite as energy sources for the extreme acidophilic bacterium Acidithiobacillus ferrooxidans in the context of mars habitability.

Past and present habitability of Mars have been intensely studied in the context of the search for signals of life. Despite the harsh conditions observed today on the planet, some ancient Mars environments could have harbored specific characteristics able to mitigate several challenges for the development of microbial life. In such environments, Fe2+ minerals like siderite (already identified on Mars), and vivianite (proposed, but not confirmed) could sustain a chemolithoautotrophic community. In this study, we investigate the ability of the acidophilic iron-oxidizing chemolithoautotrophic bacterium Acidithiobacillus ferrooxidans to use these minerals as its sole energy source. A. ferrooxidans was grown in media containing siderite or vivianite under different conditions and compared to abiotic controls. Our experiments demonstrated that this microorganism was able to grow, obtaining its energy from the oxidation of Fe2+ that came from the solubilization of these minerals under low pH. Additionally, in sealed flasks without CO2, A. ferrooxidans was able to fix carbon directly from the carbonate ion released from siderite for biomass production, indicating that it could be able to colonize subsurface environments with little or no contact with an atmosphere. These previously unexplored abilities broaden our knowledge on the variety of minerals able to sustain life. In the context of astrobiology, this expands the list of geomicrobiological processes that should be taken into account when considering the habitability of environments beyond Earth, and opens for investigation the possible biological traces left on these substrates as biosignatures.

Dawn of diverse shelled and carbonaceous animal microfossils at ~ 571 Ma.

The Ediacaran-Cambrian transition documents a critical stage in the diversification of animals. The global fossil record documents the appearance of cloudinomorphs and other shelled tubular organisms followed by non-biomineralized small carbonaceous fossils and by the highly diversified small shelly fossils between ~ 550 and 530 Ma. Here, we report diverse microfossils in thin sections and hand samples from the Ediacaran Bocaina Formation, Brazil, separated into five descriptive categories: elongate solid structures (ES); elongate filled structures (EF); two types of equidimensional structures (EQ 1 and 2) and elongate hollow structures with coiled ends (CE). These specimens, interpreted as diversified candidate metazoans, predate the latest Ediacaran biomineralized index macrofossils of the Cloudina-Corumbella-Namacalathus biozone in the overlying Tamengo Formation. Our new carbonate U-Pb ages for the Bocaina Formation, position this novel fossil record at 571 ± 9 Ma (weighted mean age). Thus, our data point to diversification of metazoans, including biomineralized specimens reminiscent of sections of cloudinids, protoconodonts, anabaritids, and hyolithids, in addition to organo-phosphatic surficial coverings of animals, demonstrably earlier than the record of the earliest known skeletonized metazoan fossils.

Ultraviolet Resistance of Microorganisms Isolated from Uranium-Rich Minerals from Perus, Brazil.

The district of Perus, located in the city of São Paulo, Brazil, is renowned for its weathered granitic-pegmatitic masses, which harbor a significant number of uraniferous minerals that contribute to ionizing radiation levels up to 20 times higher than the background levels. In this study, aseptically collected mineral samples from the area were utilized to isolate 15 microorganisms, which were subjected to pre-screening tests involving UV-C and UV-B radiation. The microorganisms that exhibited the highest resistance to ultraviolet (UV) radiation were selected for the construction of survival curves for UV-C, broad-band UV-B, and solar simulation resistance testing. Subsequently, the four strains that demonstrated superior survival capabilities under UV radiation exposure were chosen for 16S rRNA gene sequencing. Among these, Nocardioides sp. O4R and Nocardioides sp. MA2R demonstrated the most promising outcomes in the UV radiation resistance assessments, showcasing comparable performance to the well-established radioresistant model organism Deinococcus radiodurans. These findings underscore the potential of naturally occurring high-radiation environments as valuable resources for the investigation of UV-resistant microorganisms.

The Applicability of Dynamic External Fixator in a Prospective Evaluation of Open Tibial Fracture Treatment.

Aim: This prospective study assessed the clinical and radiological outcomes of open tibia fractures treated with a dynamic external fixator. Materials and methods: Twenty-five patients underwent surgical debridement and stabilisation with a dynamic external fixator between November 2016 and April 2022. Regular follow-up evaluated bone healing progression. Results: Favourable outcomes were demonstrated in 20 patients. However, there were three cases of non-union, two of which subsequently deformed, and two cases of pin site-related infection. There were no fracture site infections. Conclusion: This study demonstrates the use of dynamic external fixation in the treatment of open tibia fractures. The low incidence of complications suggests its effectiveness and potential. How to cite this article: Bezerra BS, Araujo TA, Cardonia GG, et al. The Applicability of Dynamic External Fixator in a Prospective Evaluation of Open Tibial Fracture Treatment. Strategies Trauma Limb Reconstr 2024;19(1):36-39.

Improved Chemical and Radiochemical Synthesis of Neuropeptide Y Y2 Receptor Antagonist N-Methyl-JNJ-31020028 and Preclinical Positron Emission Tomography Studies.

Neuropeptide Y (NPY) is one of the most abundant peptides in the central nervous system of mammals and is involved in several physiological processes through NPY Y1, Y2, Y4 and Y5 receptors. Of those, the Y2 receptor has particular relevance for its autoreceptor role in inhibiting the release of NPY and other neurotransmitters and for its involvement in relevant mechanisms such as feeding behaviour, cognitive processes, emotion regulation, circadian rhythms and disorders such as epilepsy and cancer. PET imaging of the Y2 receptor can provide a valuable platform to understand this receptor's functional role and evaluate its potential as a therapeutic target. In this work, we set out to refine the chemical and radiochemical synthesis of the Y2 receptor antagonist N-[11C]Me-JNJ31020028 for in vivo PET imaging studies. The non-radioactive reference compound, N-Me-JNJ-31020028, was synthesised through batch synthesis and continuous flow methodology, with 43% and 92% yields, respectively. N-[11C]Me-JNJ-31020028 was obtained with a radiochemical purity > 99%, RCY of 31% and molar activity of 156 GBq/µmol. PET imaging clearly showed the tracer's biodistribution in several areas of the mouse brain and gut where Y2 receptors are known to be expressed.

Two novel synthetic xanthenodiones as antimicrobial, anti-adhesive and antibiofilm compounds against methicillin resistant Staphylococcus aureus.

Methicillin-resistant Staphylococcus aureus (MRSA) is widely recognized as a causative agent for various infections acquired in healthcare settings as well as in the community. Given the limited availability of effective antimicrobial agents to combat MRSA infections, there is an increasing need to explore alternative therapeutic strategies. This study aimed to assess the antimicrobial, anti-adhesive, anti-biofilm properties, and toxicity of 175 newly synthesized compounds, belonging to seven different classes, against MRSA. Initially, the compounds underwent screening for antimicrobial activity using the agar diffusion method. Subsequently, active compounds underwent further evaluation to determine their minimum inhibitory concentrations through microdilution. Anti-biofilm and anti-adhesive properties were assessed using the crystal violet method, while toxicity was tested using the alternative infection model Galleria mellonella. Among the tested compounds, two xanthenodiones exhibited the most promising activities, displaying bactericidal effects along with anti-adhesive and anti-biofilm properties. Moreover, the observed non-toxicity in G. mellonella larvae suggests that these compounds hold significant potential as alternative therapeutic options to address the escalating challenge of MRSA resistance in both hospital and community settings.

INJURY EPIDEMIOLOGY IN BEACH TENNIS: INCIDENCE AND RISK FACTORS.

Introduction: Due to the growing increase in beach tennis practice in Brazil and the lack of studies on the injuries that occur in this sport, it has become necessary to develop more research on the subject. Objective: to identify risk and protection factors for injuries in beach tennis, in order to generate prevention strategies for musculoskeletal injuries. Method: A cross-sectional epidemiological study, level 3 of evidence, was carried out through an electronic form with 698 Beach Tennis players, who answered questions about their relationship with the practice of the sport and occurrences of injuries. We researched the prevalence of injuries, their types, and their relation with personal physical characteristics and the practice of other sports. Results: We found a positive relationship between injuries when associated with longer exposure time and the presence of a previous injury. We did not find differences regarding BMI, gender, and stretching and muscle strengthening performance. Conclusion: the most frequent non-traumatic injuries were to the elbow and shoulder (tendonitis) and traumatic (sprain) injuries to the knee and ankle. Level of Evidence II; Cohort Study.

Introdução: Devido ao crescente aumento da prática de Beach Tennis no Brasil e a carência de estudos sobre as lesões que ocorrem nesse esporte se faz necessário o desenvolvimento de mais pesquisas sobre o tema. Objetivo: identificar fatores de risco e de proteção para lesões no Beach Tennis, afim de gerar estratégias de prevenção às injurias musculoesqueléticas. Método: realizado estudo epidemiológico transversal nível 3 de evidência através de um formulário eletrônico com 698 praticantes de Beach Tennis, que responderam questionamentos sobre sua relação com a prática do esporte e ocorrências de lesões. Pesquisamos a prevalência das lesões e seus tipos, assim como sua relação com as características físicas pessoais e prática de outros esportes. Resultados: encontramos relação de positividade para lesões quando associadas a maior tempo de exposição e presença de lesão prévia. Não encontramos diferença quanto ao IMC, sexo e a realização de alongamento e fortalecimento muscular. Conclusão: as lesões mais frequentes não traumáticas foram no cotovelo e ombro (tendinite) e traumáticas (entorse) de joelho e tornozelo. Nível de Evidência II; Estudo de Coorte.

Environment geometry alters subiculum boundary vector cell receptive fields in adulthood and early development.

Boundaries to movement form a specific class of landmark information used for navigation: Boundary Vector Cells (BVCs) are neurons which encode an animal's location as a vector displacement from boundaries. Here we characterise the prevalence and spatial tuning of subiculum BVCs in adult and developing male rats, and investigate the relationship between BVC spatial firing and boundary geometry. BVC directional tunings align with environment walls in squares, but are uniformly distributed in circles, demonstrating that environmental geometry alters BVC receptive fields. Inserted barriers uncover both excitatory and inhibitory components to BVC receptive fields, demonstrating that inhibitory inputs contribute to BVC field formation. During post-natal development, subiculum BVCs mature slowly, contrasting with the earlier maturation of boundary-responsive cells in upstream Entorhinal Cortex. However, Subiculum and Entorhinal BVC receptive fields are altered by boundary geometry as early as tested, suggesting this is an inherent feature of the hippocampal representation of space.

Synergism between molecules derived from Garcinia brasiliensis and antimicrobial drugs on field isolates of Mycoplasma hyopneumoniae.

Mycoplasma hyopneumoniae (M. hyopneumoniae) is one of the smallest free-living bacteria found in nature; it has an extremely small genome and lacks a cell wall. It is the main etiological agent of porcine enzootic pneumonia (EP), a chronic respiratory disease with worldwide distribution that causes significant losses in swine production. Due to the great economic impact caused by EP, new strategies for treating and controlling this agent are researched. The objective of this study was to verify the anti-M. hyopneumoniae activity of compounds derived from Garcinia brasiliensis and the synergism with the main antimicrobials used in the treatment of EP; this is the first study assessing the synergism between bioactive molecules and antimicrobial compounds in vitro against isolates of M. hyopneumoniae. The minimum inhibitory concentrations (MICs) of the antimicrobials tiamulin, valnemulin, and enrofloxacin, as well as the bioactive compounds guttiferone-A (Gut-A), 7-epiculsone (7-Epic), copper 7-epiculsone (7-Epic-Cu), and benzophenone, were determined. Subsequently, the interactions of antibiotics with the compounds were evaluated using the checkerboard method. Three field M. hyopneumoniae isolates were used, and the J strain was used as a control. The MIC values of the antimicrobials compared to the field isolates were equal to and lower than those of the reference strain J. Among the compounds used, 7-Epic-Cu showed the lowest MIC value. Synergistic association was observed for Gut-A with tiamulin and valnemulin, whereas 7-Epic and 7-Epic-Cu showed synergistic action with enrofloxacin. No synergistic effect was observed for benzophenone. Despite being an initial study, the results suggest that these combinations hold promise for the treatment of infections caused by M. hyopneumoniae.

Injury epidemiology in beach tennis: incidence and risk factors / Epidemiologia das lesões no beach tennis: incidência e fatores de risco

ABSTRACT Introduction: Due to the growing increase in beach tennis practice in Brazil and the lack of studies on the injuries that occur in this sport, it has become necessary to develop more research on the subject. Objective: to identify risk and protection factors for injuries in beach tennis, in order to generate prevention strategies for musculoskeletal injuries. Method: A cross-sectional epidemiological study, level 3 of evidence, was carried out through an electronic form with 698 Beach Tennis players, who answered questions about their relationship with the practice of the sport and occurrences of injuries. We researched the prevalence of injuries, their types, and their relation with personal physical characteristics and the practice of other sports. Results: We found a positive relationship between injuries when associated with longer exposure time and the presence of a previous injury. We did not find differences regarding BMI, gender, and stretching and muscle strengthening performance. Conclusion: the most frequent non-traumatic injuries were to the elbow and shoulder (tendonitis) and traumatic (sprain) injuries to the knee and ankle. Level of Evidence II; Cohort Study.

RESUMO Introdução: Devido ao crescente aumento da prática de Beach Tennis no Brasil e a carência de estudos sobre as lesões que ocorrem nesse esporte se faz necessário o desenvolvimento de mais pesquisas sobre o tema. Objetivo: identificar fatores de risco e de proteção para lesões no Beach Tennis, afim de gerar estratégias de prevenção às injurias musculoesqueléticas. Método: realizado estudo epidemiológico transversal nível 3 de evidência através de um formulário eletrônico com 698 praticantes de Beach Tennis, que responderam questionamentos sobre sua relação com a prática do esporte e ocorrências de lesões. Pesquisamos a prevalência das lesões e seus tipos, assim como sua relação com as características físicas pessoais e prática de outros esportes. Resultados: encontramos relação de positividade para lesões quando associadas a maior tempo de exposição e presença de lesão prévia. Não encontramos diferença quanto ao IMC, sexo e a realização de alongamento e fortalecimento muscular. Conclusão: as lesões mais frequentes não traumáticas foram no cotovelo e ombro (tendinite) e traumáticas (entorse) de joelho e tornozelo. Nível de Evidência II; Estudo de Coorte.

Topical antimicrobial formulations using medicinal plant-derived essential oils targeting methicillin resistant Staphylococcus aureus.

Methicillin-resistant Staphylococcus aureus (MRSA) causes a variety of healthcare-associated and community-acquired infections. Due to limited availability of effective antimicrobials for treating MRSA infections, there is a growing need to explore alternative therapeutic approaches. Here, the antimicrobial activities of 19 oils, popularly used for their medicinal properties, were tested against MRSA USA300. Oils obtained from cinnamon, clove, tangerine, and coriander showed the most promising activities, demonstrating bactericidal, anti-adhesive and anti-biofilm activities, and synergistic properties with common antibiotics. Given that clove and cinnamon oils showed the best activities, they were incorporated into topical formulations. Not only did the formulations with oils maintain antimicrobial and anti-adhesive activities, but their anti-biofilm property was potentiated. Tests on Galleria mellonella larvae suggested that the formulation is non-toxic. The formulations proposed here are a great alternative for the decolonisation of surfaces containing MRSA and can help circumventing antimicrobial resistance, a growing threat in the hospital environment.

Trunk variability and local dynamic stability during gait after generalized fatigue induced by incremental exercise test in young women in different phases of the menstrual cycle.

Purpose: The purpose of this study was to identify how generalized fatigue along with hormonal changes throughout the menstrual cycle affects trunk variability and local dynamic stability during gait. Methods: General fatigue was induced by an incremental test on a treadmill, and the menstrual cycle was divided into three phases: follicular, ovulatory, and luteal. Twenty-six healthy, young volunteers (aged 18 to 28 years) who did not use oral contraceptives or other hormonal drugs with a regular menstrual cycle participated in the study. They walked on the treadmill for 4 min at the preferred speed, before the incremental test, followed by four sets of 4 min alternating between walking, also at preferred speed, and resting. From trunk kinematic data, the following were extracted: the mean of the standard deviation along strides, as a measure of variability, and the maximum Lyapunov exponent, as a measure of local dynamic stability (LDS). Results: After the incremental test, variability increased, and LDS decreased. However, they showed a tendency to return to the initial value faster in women compared to previous results for men. In the follicular phase, which has less hormonal release, the volunteers had an almost complete recovery in LDS soon after the first rest interval, suggesting that female hormones can interfere with fatigue recovery. Nevertheless, concerning the LDS, it was significantly lower in the luteal phase than in the follicular phase. Conclusion: Women that are not taking oral contraceptives should be aware that they are susceptible to increased gait instabilities in the pre-menstrual phase after strenuous activities.

Aspen Plus simulation for effluent reuse in thermomechanical pulp mills.

The objective of this study was to evaluate the closing of the water circuit and reusing the treated effluent in the production of TMP, using simulations performed with the Aspen Plus®. The treated effluent was reused to replace 50, 75 and 100% of the well water. An adaptation of the Aspen Plus® program simulating the TMP production process and a dynamic simulation test to verify the accumulation of non-process elements (NPEs) in industrial processes at different proportions of reuse were evaluated. The quality of the final product was assessed in laboratory bleaching tests for pulp brightness and brightness reversion. The concentrations of the NPE were 0.00097, 0.00122 and 0.00145 kmol/h for Mn2+, 0.012929, 0.018368 and 0.023595 kmol/h for Fe2+ and 0.000542, 0.000722 and 0.000948 kmol/h for Cu2+, with the recycling of the treated effluent of 50, 75 and 100%, respectively. The brightness and brightness reversion of the pulp were similar with the different proportions of effluent reuse and with the use of fresh industrial water, with values ranging from 83.37 to 83.97% ISO and 5.43 to 6.38 ISO units, respectively. The use of treated effluent did not affect the pulp quality, which could diminish the water use a pulp mil.

Applications of fluorescence spectroscopy in protein conformational changes and intermolecular contacts.

Emission fluorescence is one of the most versatile and powerful biophysical techniques used in several scientific subjects. It is extensively applied in the studies of proteins, their conformations, and intermolecular contacts, such as in protein-ligand and protein-protein interactions, allowing qualitative, quantitative, and structural data elucidation. This review, aimed to outline some of the most widely used fluorescence techniques in this area, illustrate their applications and display a few examples. At first, the data on the intrinsic fluorescence of proteins is disclosed, mainly on the tryptophan side chain. Predominantly, research to study protein conformational changes, protein interactions, and changes in intensities and shifts of the fluorescence emission maximums were discussed. Fluorescence anisotropy or fluorescence polarization is a measurement of the changing orientation of a molecule in space, concerning the time between the absorption and emission events. Absorption and emission indicate the spatial alignment of the molecule's dipoles relative to the electric vector of the electromagnetic wave of excitation and emitted light, respectively. In other words, if the fluorophore population is excited with vertically polarized light, the emitted light will retain some polarization based on how fast it rotates in solution. Therefore, fluorescence anisotropy can be successfully used in protein-protein interaction investigations. Then, green fluorescent proteins (GFPs), photo-transformable fluorescent proteins (FPs) such as photoswitchable and photoconvertible FPs, and those with Large Stokes Shift (LSS) are disclosed in more detail. FPs are potent tools for the study of biological systems. Their versatility and wide range of colours and properties allow many applications. Finally, the application of fluorescence in life sciences is exposed, especially the application of FPs in fluorescence microscopy techniques with super-resolution that enables precise in vivo photolabeling to monitor the movement and interactions of target proteins.

Criteria for selection and classification of studies in medical events.

OBJECTIVE: The aim of this study was to evaluate the impact of study methodology and evaluation type on the selection of studies during the presentation of scientific events. METHODS: A prospective, observational, transversal approach was applied to a cohort of studies that were submitted for presentation at the 2021 Brazilian Breast Cancer Symposium. Three forms of criteria (CR) were presented. CR1 was based on six criteria (method, ethics, design, originality, promotion, and social contribution); CR2 graded the studies from 0 to 10 for each study, and CR3 was based on five criteria (presentation, method, originality, scientific knowledge, and social contribution). To evaluate the item correlation, Cronbach's alpha and factorial analysis were performed. For the evaluation of differences between the tests, we used the Kruskal-Wallis and post-hoc Dunn tests. To determine the differences in the study classifications, we used the Friedman test and Namenyi's all-pairs comparisons. RESULTS: A total of 122 studies were evaluated. There was also a good correlation with the items concerning criterion 1 (α=0.730) and 3 (α=0.937). Evaluating CR1 methodology, study design and social contribution (p=0.741) represents the main factor and CR3 methodology, and the scientific contribution (p=0.994) represents the main factor. The Kruskal-Wallis test showed differences in the results (p<0.001) for all the criteria that were used [CR1-CR2 (p<0.001), CR1-CR3 (p<0.001), and CR2-CR3 (p=0.004)]. The Friedman test showed differences in the ranking of the studies (p<0.001) for all studies (p<0.01). CONCLUSION: Methodologies that use multiple criteria show good correlation and should be taken into account when ranking the best studies.

Photoantibacterial Poly(vinyl)chloride Films Applying Curcumin Derivatives as Bio-Based Plasticizers and Photosensitizers.

Herein we describe the design of natural curcumin ester and ether derivatives and their application as potential bioplasticizers, to prepare photosensitive phthalate-free PVC-based materials. The preparation of PVC-based films incorporating several loadings of newly synthesized curcumin derivatives along with their standard solid-state characterization is also described. Remarkably, the plasticizing effect of the curcumin derivatives in the PVC material was found to be similar to that observed in previous PVC-phthalate materials. Finally, studies applying these new materials in the photoinactivation of S. aureus planktonic cultures revealed a strong structure/activity correlation, with the photosensitive materials reaching up to 6 log CFU reduction at low irradiation intensities.

First case report of feline sporotrichosis caused by Sporothrix brasiliensis in the state of Ceará - Brazil.

Feline sporotrichosis is a zoonotic mycosis caused by fungi belonging to the Sporothrix schenckii complex. In the state of Ceará, there are no reports of isolation of this fungus in cats. This study presents the first report of feline sporotrichosis caused by the species Sporothrix brasiliensis in the state of Ceará - Brazil. The diagnosis was made through cytopathological examination, mycological culture and PCR. The findings were compatible with feline sporotrichosis caused by Sporothrix brasiliensis.

Formulations of essential oils obtained from plants traditionally used as condiments or traditional medicine active against Staphylococcus aureus isolated from dairy cows with mastitis.

The prophylactic and therapeutic overuse of antimicrobials on the farm has contributed to the emergence of hard-to-fight bacterial strains causing bovine mastitis. Aiming at alternative therapies, this study evaluated the antimicrobial activity of 20 essential oils against clinical Staphylococcus aureus strains. Of them, five with strong activities were selected and evaluated for their minimum inhibitory concentrations (MIC) in culture medium and milk, cytotoxicity against bovine mammary cells (MAC-T), antiadhesive properties, and interactions among themselves and with cefoperazone. The oils remained active on milk, were not cytotoxic, and some concentrations stimulated MAC-T cells growth, suggesting healing potential. Subinhibitory concentrations of Coriandrum sativum, Origanum vulgare, Syzygium aromaticum, and Thymus vulgaris reduced biofilm formation by at least 80%. Several oil and cefoperazone combinations displayed additive interaction, with O. vulgare and C. sativum showing the most promising results. We developed formulations for being used as prophylactic postdipping solutions in the field, containing different concentrations (1% or 3%) of the active oils, alone or in combination, with 3% glycerin, 1% Tween 80, and water. The formulations showed strong antimicrobial activity in milk and enhanced antiadhesive properties, specially when two oils were combined in the formula, indicating promising biotechnological and therapeutical applications.

Chemical composition variation of essential oils of Copaifera langsdorffii Desf. from different vegetational formations.

This study aims to provide information about the chemical profile of the essential oil from C. langsdorffii resin in areas of Cerradão, Carrasco, and Humid Forest. In order to obtain the essential oils, oil-resin was submitted to hydrodistillation process, and the chemical components were analyzed by gas chromatography coupled to mass spectrometry (GC/MS). Twenty-six constituents were identified in the essential oil of C. langsdorffii resin, of which 12 were present in Cerradão, 15 in Carrasco and 18 in Humid Forest, with ß-bisabolene, caryophyllene oxide, γ-muurolene, α-caryophyllene and ß-caryophyllene common to the three phytophysiognomies. Among the studied areas, the resin collection varied from 2.652 g to 20.263 g, while the essential oil yield varied from 2.216 % to 11.764 %. A concentration range of 0.60 % to 84.57 % was recorded among the compounds in the three study areas. There was variation in chemical composition both among phytophysiognomies and among individuals from the same location, where ß-caryophyllene showed to be the majority for all areas studied, being present in all individuals from Cerradão, Carrasco and Humid Forest.