The angiotensin-(1-7)/MasR axis improves pneumonia caused by Pseudomonas aeruginosa: Extending the therapeutic window for antibiotic therapy.

Pseudomonas aeruginosa is a frequent cause of antimicrobial-resistant hospital-acquired pneumonia, especially in critically ill patients. Inflammation triggered by P. aeruginosa infection is necessary for bacterial clearance but must be spatially and temporally regulated to prevent further tissue damage and bacterial dissemination. Emerging data have shed light on the pro-resolving actions of angiotensin-(1-7) [Ang-(1-7)] signaling through the G protein-coupled receptor Mas (MasR) during infections. Herein, we investigated the role of the Ang-(1-7)/Mas axis in pneumonia caused by P. aeruginosa by using genetic and pharmacological approach and found that Mas receptor-deficient animals developed a more severe form of pneumonia showing higher neutrophilic infiltration into the airways, bacterial load, cytokines, and chemokines production and more severe pulmonary damage. Conversely, treatment of pseudomonas-infected mice with Ang-(1-7) was able to decrease neutrophilic infiltration in airways and lungs, local and systemic levels of pro-inflammatory cytokines and chemokines, and increase the efferocytosis rates, mitigating lung damage/dysfunction caused by infection. Notably, the therapeutic association of Ang-(1-7) with antibiotics improved the survival rates of mice subjected to lethal inoculum of P. aeruginosa, extending the therapeutic window for imipenem. Mechanistically, Ang-(1-7) increased phagocytosis of bacteria by neutrophils and macrophages to accelerate pathogen clearance. Altogether, harnessing the Ang-(1-7) pathway during infection is a potential strategy for the development of host-directed therapies to promote mechanisms of resistance and resilience to pneumonia.

Challenges and opportunities for access to Advanced Therapy Medicinal Products in Brazil.

BACKGROUND AIMS: The marketing authorization of Advanced Therapy Medicinal Products (ATMPs) in Brazil is recent. The features of these therapies impose specialized regulatory action and are consequently challenging for developers. The goal of this study was to identify the industry's experience in clinical development, marketing authorization and access to ATMPs through the Unified Health System (SUS, acronym in Portuguese), from a regulatory perspective. METHODS: A survey containing structured questions was conducted among research participants who work at companies that commercialize ATMPs. A descriptive analysis was performed. RESULTS: We invited 15 foreign pharmaceutical companies, of which 10 agreed to participate. Overall, participants assessed that Brazil has a well-established regulatory system, especially the sanitary registration by the National Health Surveillance Agency (Anvisa), which ensures the quality, safety, and efficacy of the products. The Agency's good interaction with the regulated sector, the harmonization of sanitary and ethical assessment systems with other countries, and the analysis time in the biosafety assessment of Genetically Modified Organisms (GMOs) stand out as positive in industry's evaluation. On the other hand, it is important to advance the pricing regulation for these products since Brazilian regulations do not establish specific criteria for ATMP. One of the biggest challenges is the difficulty for the SUS in reimbursing these very high-cost therapies, especially using current Health Technology Assessment (HTA) methods. CONCLUSIONS: Considering the increasing number of approvals of cell and gene therapies in Brazil in the coming years, a close dialogue between the industry and the public sector is recommended to advance regulatory improvements (pricing and HTA). Additionally, the construction of policies to promote the national Health Economic-Industrial Complex, based on a mission-oriented vision that encourages innovative models of financing, especially those that consider risk-sharing and co-financing technologies, will help provide the population with universal, equitable and sustainable access to ATMP in the SUS.

Angiotensin-(1-7) decreases inflammation and lung damage caused by betacoronavirus infection in mice.

OBJECTIVE: Pro-resolving molecules, including the peptide Angiotensin-(1-7) [Ang-(1-7)], have potential adjunctive therapy for infections. Here we evaluate the actions of Ang-(1-7) in betacoronavirus infection in mice. METHODS: C57BL/6J mice were infected intranasally with the murine betacoronavirus MHV-3 and K18-hACE2 mice were infected with SARS-CoV-2. Mice were treated with Ang-(1-7) (30 µg/mouse, i.p.) at 24-, 36-, and 48-hours post-infection (hpi) or at 24, 36, 48, 72, and 96 h. For lethality evaluation, one additional dose of Ang-(1-7) was given at 120 hpi. At 3- and 5-days post- infection (dpi) blood cells, inflammatory mediators, viral loads, and lung histopathology were evaluated. RESULTS: Ang-(1-7) rescued lymphopenia in MHV-infected mice, and decreased airways leukocyte infiltration and lung damage at 3- and 5-dpi. The levels of pro-inflammatory cytokines and virus titers in lung and plasma were decreased by Ang-(1-7) during MHV infection. Ang-(1-7) improved lung function and increased survival rates in MHV-infected mice. Notably, Ang-(1-7) treatment during SARS-CoV-2 infection restored blood lymphocytes to baseline, decreased weight loss, virus titters and levels of inflammatory cytokines, resulting in improvement of pulmonary damage, clinical scores and lethality rates. CONCLUSION: Ang-(1-7) protected mice from lung damage and death during betacoronavirus infections by modulating inflammation, hematological parameters and enhancing viral clearance.

Immobilization of the ß-galactosidase enzyme by encapsulation in polymeric matrices for application in the dairy industry.

Lactose intolerance affects approximately 65% of the global adult population, leading to the demand for lactose-free products. The enzyme ß-galactosidase (ßG) is commonly used in the industry to produce such products, but its recovery after lactose hydrolysis is challenging. In this scenario, the study aims to encapsulate ßG within capsules, varying in dimensions and wall materials, to ensure their suitability for efficient industrial recovery. The enzyme ßG was encapsulated through ionic gelation using alginate and its blends with pectin, maltodextrin, starch, or whey protein as wall materials. The capsules produced underwent evaluation for encapsulation efficiency, release profiles, activity of the ßG enzyme, and the decline in enzyme activity when reused over multiple cycles. Alginate at 5% wt/vol concentrations, alone or combined with polymers such as maltodextrin, starch, or whey protein, achieved encapsulation efficiencies of approximately 98%, 98%, 80%, and 88%, respectively. The corresponding enzyme recovery rates were 34%, 19%, 31%, and 48%. Capsules made with an alginate-pectin blend exhibited no significant hydrolysis and maintained an encapsulation efficiency of 79%. Encapsulation with alginate alone demonstrated on poor retention of enzyme activity, showing a loss of 74% after just 4 cycles of reuse. Conversely, when alginate was mixed with starch or whey protein concentrate, the loss of enzyme activity was less than 40% after 4 reuses. These results highlight the benefits of combining encapsulation materials to improve enzyme recovery and reuse, offering potential economic advantages for the dairy industry.

Exploring the impact of high-energy diets on cattle: Insights into subacute rumen acidosis, insulin resistance, and hoof health.

Cattle lameness remains a significant concern, causing economic losses and compromising animal welfare. Claw horn lesions have been identified as a major cause of lameness in dairy cows, but their correlation with high-energy diets and ruminal acidosis remains unclear. Hence, the primary objective of this study was to assess the effects of a high-starch diet and a conventional diet on the rumen environment, acute-phase proteins, and metabolic alterations, with a particular focus on insulin resistance and the consequent implications for the histology of the hooves in Holstein steers. A total of 16 animals were divided into the high-starch (HS; 37% starch) and conventional (CON; 16.8% starch) groups. Glucose tolerance tests (GTT), blood analyses, rumen fluid analyses, and histological evaluations of the hoof tissue were conducted over a 102-d experimental period. The HS group showed a lower ruminal pH than the CON group, and with values indicating SARA. The plasma glucose and IGF-1 concentrations were higher in the HS group, suggesting an anabolic state. Both groups exhibited an increase in the insulin area under the curve (AUC) after the GTT on d 102. Histological analysis of the hooves showed a reduction in the length and width of the epidermal lamella in both groups. We found a significant negative correlation between the insulin AUC and the length and width of the epidermal lamella. Because both groups were similarly affected, the hypothesis that histological alterations were caused by the experimental diets still needs confirmation. Additionally, the development of SARA was not essential for the observed histological changes in the hoof. Further studies are warranted to thoroughly investigate the role of insulin and IGF-1 imbalances in claw health.

Staphylococcus aureus in Dairy Industry: Enterotoxin Production, Biofilm Formation, and Use of Lactic Acid Bacteria for Its Biocontrol.

Staphylococcus aureus is a well-known pathogen capable of producing enterotoxins during bacterial growth in contaminated food, and the ingestion of such preformed toxins is one of the major causes of food poisoning around the world. Nowadays 33 staphylococcal enterotoxins (SEs) and SE-like toxins have been described, but nearly 95% of confirmed foodborne outbreaks are attributed to classical enterotoxins SEA, SEB, SEC, SED, and SEE. The natural habitat of S. aureus includes the skin and mucous membranes of both humans and animals, allowing the contamination of milk, its derivatives, and the processing facilities. S. aureus is well known for the ability to form biofilms in food processing environments, which contributes to its persistence and cross-contamination in food. The biocontrol of S. aureus in foods by lactic acid bacteria (LAB) and their bacteriocins has been studied for many years. Recently, LAB and their metabolites have also been explored for controlling S. aureus biofilms. LAB are used in fermented foods since in ancient times and nowadays characterized strains (or their purified bacteriocin) can be intentionally added to prolong food shelf-life and to control the growth of potentially pathogenic bacteria. Regarding the use of these microorganism and their metabolites (such as organic acids and bacteriocins) to prevent biofilm development or for biofilm removal, it is possible to conclude that a complex network behind the antagonistic activity remains poorly understood at the molecular level. The use of approaches that allow the characterization of these interactions is necessary to enhance our understanding of the mechanisms that govern the inhibitory activity of LAB against S. aureus biofilms in food processing environments.

Mesenchymal Stromal Cell-Based Products: Challenges and Clinical Therapeutic Options.

Mesenchymal stromal cell (MSC)-based advanced therapy medicinal products (ATMPs) are being tried in a vast range of clinical applications. These cells can be isolated from different donor tissues by using several methods, or they can even be derived from induced pluripotent stem cells or embryonic stem cells. However, ATMP heterogeneity may impact product identity and potency, and, consequently, clinical trial outcomes. In this review, we discuss these topics and the need to establish minimal criteria regarding the manufacturing of MSCs so that these innovative therapeutics may be better positioned to contribute to the advancement of regenerative medicine.

Metrics of care and cardiovascular outcomes in patients with ST-elevation myocardial infarction treated with pharmacoinvasive strategy: a decade-long network in a populous city in Brazil.

BACKGROUND: Pharmacoinvasive strategy is an effective myocardial reperfusion therapy when primary percutaneous coronary intervention (p-PCI) cannot be performed in a timely manner. METHODS: Authors sought to evaluate metrics of care and cardiovascular outcomes in a decade-long registry of a pharmacoinvasive strategy network for the treatment of ST-elevation myocardial infarction (STEMI). Data from a local network including patients undergoing fibrinolysis in county hospitals and systematically transferred to the tertiary center were accessed from March 2010 to September 2020. Numerical variables were described as median and interquartile range. Area under the curve (AUC-ROC) was used to analyze the predictive value of TIMI and GRACE scores for in-hospital mortality. RESULTS: A total of 2,710 consecutive STEMI patients aged 59 [51-66] years, 815 women (30.1%) and 837 individuals with diabetes (30.9%) were analyzed. The time from symptom onset to first-medical-contact was 120 [60-210] minutes and the door-to-needle time was 70 [43-115] minutes. Rescue-PCI was required in 929 patients (34.3%), in whom the fibrinolytic-catheterization time was 7.2 [4.9-11.8] hours, compared to 15.7 [6.8-22,7] hours in those who had successful lytic reperfusion. All cause in-hospital mortality occurred in 151 (5.6%) patients, reinfarction in 47 (1.7%) and ischemic stroke in 33 (1.2%). Major bleeding occurred in 73 (2.7%) patients, including 19 (0.7%) cases of intracranial bleeding. C-statistic confirmed that both scores had high predictive values for in-hospital mortality, demonstrated by TIMI AUC-ROC of 0.80 [0,77-0.84] and GRACE AUC-ROC of 0.86 [0.83-0.89]. CONCLUSION: In a real world registry of a decade-long network for the treatment of ST-elevation myocardial infarction based on the pharmacoinvasive strategy, low rates of in-hospital mortality and cardiovascular outcomes were observed, despite prolonged time metrics for both fibrinolytic therapy and rescue-PCI. Register Clinicaltrials.gov NCT02090712 date of first registration 18/03/2014.

Anthracycline-induced cardiotoxicity and cell senescence: new therapeutic option?

Anthracyclines are chemotherapeutic drugs widely used in the frontline of cancer treatment. The therapeutic mechanisms involve the stabilization of topoisomerase IIα, DNA, and the anthracycline molecule in a ternary complex that is recognized as DNA damage. Redox imbalance is another vital source of oxidative DNA damage. Together, these mechanisms lead to cytotoxic effects in neoplastic cells. However, anthracycline treatment can elicit cardiotoxicity and heart failure despite the therapeutic benefits. Topoisomerase IIß and oxidative damage in cardiac cells have been the most reported pathophysiological mechanisms. Alternatively, cardiac cells can undergo stress-induced senescence when exposed to anthracyclines, a state primarily characterized by cell cycle arrest, organelle dysfunction, and a shift to senescence-associated secretory phenotype (SASP). The SASP can propagate senescence to neighboring cells in an ongoing process that leads to the accumulation of senescent cells, promoting cellular dysfunction and extracellular matrix remodeling. Therefore, the accumulation of senescent cardiac cells is an emerging pathophysiological mechanism associated with anthracycline-induced cardiotoxicity. This paradigm also raises the potential for therapeutic approaches to clear senescent cells in treating anthracycline-induced cardiotoxicity (i,e, senolytic therapies).

Extracellular Vesicles and Cardiac Aging.

Global population aging is a major challenge to health and socioeconomic policies. The prevalence of diseases progressively increases with aging, with cardiovascular disease being the major cause of mortality among elderly people. The allostatic overload imposed by the accumulation of cardiac senescent cells has been suggested to play a pivotal role in the aging-related deterioration of cardiovascular function. Senescent cells exhibit intrinsic disorders and release a senescence-associated secretory phenotype (SASP). Most of these SASP compounds and damaged molecules are released from senescent cells by extracellular vesicles (EVs). Once secreted, these EVs can be readily incorporated by recipient neighboring cells and elicit cellular damage or otherwise can promote extracellular matrix remodeling. This has been associated with the development of cardiac dysfunction, fibrosis, and vascular calcification, among others. The molecular signature of these EVs is highly variable and might provide important information for the development of aging-related biomarkers. Conversely, EVs released by the stem and progenitor cells can exert a rejuvenating effect, raising the possibility of future anti-aging therapies.

Effects of calcium chloride substitution on the physicochemical properties of Minas Frescal cheese.

The aim in this research paper was to investigate the effect of using calcium monophosphate (MCP) and MCP mixed with commercial phosphates salts, in total or partial replacement of calcium chloride (CaCl2) in the manufacture of Minas Frescal cheese. Initially, model cheeses were made to perform the rheological analysis during the coagulation process. Of these, the five best treatments were chosen to carry out the production of Minas Frescal cheese, used only CaCl2 and MCP, and partial replacements of MCP + polyphosphate, MCP + potassium monophosphate (MKP) and MCP. The cheeses showed no significant difference in physicochemical composition, yield and syneresis, however, the cheese with partial replacement of CaCl2 by MCP + polyphosphate and MCP + MKP showed the highest hardness values, like the control. This demonstrates that it is possible to replace calcium chloride without significant changes in the physicochemical characteristics and yield of Minas Frescal cheese, and it is still possible to modulate the hardness of the cheese produced according to the type of calcium/phosphate source used. This allows the industry to replace the source of calcium in the manufacture of Minas Frescal cheese according to the desired hardness.

Aging Triggers Mitochondrial Dysfunction in Mice.

Direct analysis of isolated mitochondria from old mice enables a better understanding of heart senescence dysfunction. Despite a well-defined senescent phenotype in cardiomyocytes, the mitochondrial state in aged cardiomyocytes is still unclear. Here, we report data about mitochondrial function in old mice. Isolated cardiomyocytes' mitochondria were obtained by differential centrifugation from old and young mice hearts to perform functional analyses of mitochondrial O2 consumption, transmembrane potential, ROS formation, ATP production, and swelling. Our results show that mitochondria from old mouse hearts have reduced oxygen consumption during the phosphorylative states of complexes I and II. Additionally, these mitochondria produced more ROS and less ATP than those of young hearts. Mitochondria from old hearts also showed a depolarized membrane potential than mitochondria from young hearts and, as expected, a greater electron leak. Our results indicate that mitochondria from senescent cardiomyocytes are less efficient in O2 consumption, generating more ROS and producing less ATP. Furthermore, the phosphorylative state of complexes I and II presents a functional defect, contributing to greater leakage of protons and ROS production that can be harmful to the cell.

Pseudomonas carnis isolated from blue discolored fresh cheese and insights into the phylogeny.

Most Pseudomonas spp. are responsible for spoilage in refrigerated foods such as alteration in flavor, texture and appearance. Samples of Minas Frescal cheese with blue discoloration were analysed and contained a high Pseudomonas concentration (7.72 ± 0.36 log CFU/g). Out of the 26 Pseudomonas isolates that were analyzed in our study, 19 demonstrated the capability of producing a diffusible dark pigment. Thus, a pigment-producing isolate (C020) was selected by rep-PCR fingerprinting and subsequently subjected to whole-genome sequencing. The draft genome assembled comprises 42 contigs totaling 6,366,75 bp with an average G + C content of 59.97%, and the species prediction performed by TYGS server, based on the draft genome sequence, identified the C020 as Pseudomonas carnis. In order to investigate the phylogenetic relationships of this isolate with strains already identified of this species, we performed an analysis based on whole-genomic sequences. First, an analysis of all P. carnis genomes deposited in GenBank to date shows that 11% (4/37) are misidentified, and belong to the Pseudomonas paracarnis species. A comparative analysis based on phylogenomic analysis has showed that there is no evolutionary relationship between P. carnis strains carrying second copies of trp genes related to blue discoloration (trpABCDF). This finding reinforces the assertion that these genes are contained in a mobile genetic element. However, it is worth noting that all strains carrying these secondary gene copies have exclusively been isolated from food sources. This observation provides valuable insights into the potential origins and dispersion dynamics of this genetic trait within the species.

Landscape of Brazilian research and development public funding in advanced therapies: lessons learned and a roadmap for middle-income economies.

BACKGROUND AIMS: Advanced therapy medicinal products (ATMPs) have reached the forefront of biotechnological innovation, partly due to public funders' efforts in the early stages of research and development (R&D). Data on investment in R&D of ATMPs are recognized as scarce, particularly in developing countries. Because of the numerous peculiarities of the Brazilian health system and the science and technology (S&T) system, the country is a good example for the evaluation of public investments in R&D of ATMPs. The aim of this study is to analyze the evolution of investments made by the Ministry of Health (MoH) of Brazil and partners in the ATMP field between 2004 and 2020. METHODS: A descriptive analysis was performed based on secondary data. The analysis was based on S&T and innovation research and support for research infrastructure in the field. The database was stratified by year of funding, ATMP type, type of study or research infrastructure project, amount invested in the project, targeted disease for which clinical trials in ATMPs were developed and financing sector (health, education, S&T and economic). RESULTS: The investments coordinated by MoH (61.5%) in partnership with the S&T, education and economic sectors (38.5%) consisted of Int$137.35 million in 282 ATMP projects. Funding included S&T and innovation research (67% of the total amount) and projects to implement or maintain infrastructure in selected research centers (32.98%). With regard to global convergence, cell therapy was the type of ATMP that most benefited from public investment, totaling 82.23% of the total funding in the analyzed period. Cardiology (29%) and neurology (21%) were the main focus of clinical trials. Following the global trend of public sector R&D funding, the number of basic and pre-clinical research projects represented 78.06% of the total number of projects. CONCLUSIONS: Despite the need to implement improvements in ATMP R&D financing policy in Brazil, the country has made important steps in the field and can serve as a benchmark for other countries with socioeconomic similarities. Among the main lessons are the prioritization of research aligned with the health needs of the population, cross-sector articulation by the health policymaker to coordinate R&D efforts of the sector and formulation of a specific sector policy (Programa Genomas Brasil, the Brazilian National Program of Genomic and Precision Medicine) to promote knowledge translation.

Optimizing the Decellularized Porcine Liver Scaffold Protocol.

There are few existing methods for shortening the decellularization period for a human-sized whole-liver scaffold. Here, we describe a protocol that enables effective decellularization of the liver obtained from pigs weigh 120 ± 4.2 kg within 72 h. Porcine livers (approx. 1.5 kg) were decellularized for 3 days using a combination of chemical and enzymatic decellularization agents. After trypsin, sodium deoxycholate, and Triton X-100 perfusion, the porcine livers were completely translucent. Our protocol was efficient to promote cell removal, the preservation of extracellular matrix (ECM) components, and vascular tree integrity. In conclusion, our protocol is efficient to promote human-sized whole-liver scaffold decellularization and thus useful to generate bioengineered livers to overcome the shortage of organs.

BKCa Channel Activation Attenuates the Pathophysiological Progression of Monocrotaline-Induced Pulmonary Arterial Hypertension in Wistar Rats.

PURPOSE: In the present study, the therapeutic efficacy of a selective BKCa channel opener (compound X) in the treatment of monocrotaline (MCT)-induced pulmonary arterial hypertension (PAH) was investigated. METHODS: PAH was induced in male Wistar rats by a single injection of MCT. After two weeks, the MCT-treated group was divided into two groups that were either treated with compound X or vehicle. Compound X was administered daily at 28 mg/kg. Electrocardiographic, echocardiographic, and haemodynamic analyses were performed; ex vivo evaluations of pulmonary artery reactivity, right ventricle (RV) and lung histology as well as expression levels of α and ß myosin heavy chain, brain natriuretic peptide, and cytokines (TNFα and IL10) in heart tissue were performed. RESULTS: Pulmonary artery rings of the PAH group showed a lower vasodilatation response to acetylcholine, suggesting endothelial dysfunction. Compound X promoted strong vasodilation in pulmonary artery rings of both control and MCT-induced PAH rats. The untreated hypertensive rats presented remodelling of pulmonary arterioles associated with increased resistance to pulmonary flow; increased systolic pressure, hypertrophy and fibrosis of the RV; prolongation of the QT and Tpeak-Tend intervals (evaluated during electrocardiogram); increased lung and liver weights; and autonomic imbalance with predominance of sympathetic activity. On the other hand, treatment with compound X reduced pulmonary vascular remodelling, pulmonary flow resistance and RV hypertrophy and afterload. CONCLUSION: The use of a selective and potent opener to activate the BKCa channels promoted improvement of haemodynamic parameters and consequent prevention of RV maladaptive remodelling in rats with MCT-induced PAH.

High-frequency (22-MHz) ultrasound for assessing the depth of basal cell carcinoma invasion.

BACKGROUND: High-frequency ultrasound (HFUS) has been studied in the diagnosis and therapeutic management of basal cell carcinoma (BCC). The accuracy of this method for location of deep margins remains unknown. This study evaluates HFUS for localization of deep surgical margins in BCC. MATERIALS AND METHODS: Ultrasound images of 83 lesions from 67 patients with clinical and dermoscopic diagnosis of BCC were compared with histopathological findings. Pearson's correlation coefficient was used to assess the relationship between thickness as measured by HFUS and histopathology. RESULTS: A strong correlation between HFUS and histopathological measurements was identified (r = 0.9744, P < .001). HFUS had sensitivity of 96%, specificity of 84%, and accuracy of 91% for measurement of deep tumor margins. Factors affecting tumor measurement on HFUS include marked basophilic degeneration of collagen, presence of peritumoral hypertrophic glands or hair follicles, fibrosis, and dense inflammatory changes related to the tumor itself or to prior procedures. CONCLUSION: High-frequency ultrasound was effective in localizing deep tumor margins in BCC. Therefore, we believe that this diagnostic imaging method is important when selecting a therapeutic approach, considering Mohs micrographic surgery, and evaluating the surgical site.

Bacillus spp. Inhibit Edwardsiella tarda Quorum-Sensing and Fish Infection.

The disruption of pathogen communication or quorum-sensing (QS) via quorum-quenching (QQ) molecules has been proposed as a promising strategy to fight bacterial infections. Bacillus spp. have recognizable biotechnology applications, namely as probiotic health-promoting agents or as a source of natural antimicrobial molecules, including QQ molecules. This study characterized the QQ potential of 200 Bacillus spp., isolated from the gut of different aquaculture fish species, to suppress fish pathogens QS. Approximately 12% of the tested Bacillus spp. fish isolates (FI). were able to interfere with synthetic QS molecules. Ten isolates were further selected as producers of extracellular QQ-molecules and their QQ capacity was evaluated against the QS of important aquaculture bacterial pathogens, namely Aeromonas spp., Vibrio spp., Photobacterium damselae, Edwardsiela tarda, and Shigella sonnei. The results revealed that A. veronii and E. tarda produce QS molecules that are detectable by the Chr. violaceum biosensor, and which were degraded when exposed to the extracellular extracts of three FI isolates. Moreover, the same isolates, identified as B. subtilis, B. vezelensis, and B. pumilus, significantly reduced the pathogenicity of E. tarda in zebrafish larvae, increasing its survival by 50%. Taken together, these results identified three Bacillus spp. capable of extracellularly quenching aquaculture pathogen communication, and thus become a promising source of bioactive molecules for use in the biocontrol of aquaculture bacterial diseases.

An investigation of Y chromosome incorporations in 400 species of Drosophila and related genera.

Y chromosomes are widely believed to evolve from a normal autosome through a process of massive gene loss (with preservation of some male genes), shaped by sex-antagonistic selection and complemented by occasional gains of male-related genes. The net result of these processes is a male-specialized chromosome. This might be expected to be an irreversible process, but it was found in 2005 that the Drosophila pseudoobscura Y chromosome was incorporated into an autosome. Y chromosome incorporations have important consequences: a formerly male-restricted chromosome reverts to autosomal inheritance, and the species may shift from an XY/XX to X0/XX sex-chromosome system. In order to assess the frequency and causes of this phenomenon we searched for Y chromosome incorporations in 400 species from Drosophila and related genera. We found one additional large scale event of Y chromosome incorporation, affecting the whole montium subgroup (40 species in our sample); overall 13% of the sampled species (52/400) have Y incorporations. While previous data indicated that after the Y incorporation the ancestral Y disappeared as a free chromosome, the much larger data set analyzed here indicates that a copy of the Y survived as a free chromosome both in montium and pseudoobscura species, and that the current Y of the pseudoobscura lineage results from a fusion between this free Y and the neoY. The 400 species sample also showed that the previously suggested causal connection between X-autosome fusions and Y incorporations is, at best, weak: the new case of Y incorporation (montium) does not have X-autosome fusion, whereas nine independent cases of X-autosome fusions were not followed by Y incorporations. Y incorporation is an underappreciated mechanism affecting Y chromosome evolution; our results show that at least in Drosophila it plays a relevant role and highlight the need of similar studies in other groups.

Presence and growth prediction of Staphylococcus spp. and Staphylococcus aureus in Minas Frescal cheese, a soft fresh cheese produced in Brazil.

Physical-chemical characteristics of Minas Frescal cheese (MFC) favor the growth of Staphylococcus spp. and allow the production of enterotoxins by specific strains. Here, we aimed to characterize the physical-chemical aspects (pH, storage temperature, and salt content) and the presence of Staphylococcus spp. in MFC samples (n = 50) to support a modeling study for the growth by this microorganism. Coagulase-positive staphylococci isolates were obtained and subjected to PCR assays to identify them as Staphylococcus aureus (nuc) and to detect staphylococcal enterotoxin-related genes (sea, seb, sec, sed, see). Staphylococcus aureus growth kinetics (maximum growth rate, Grmax, and lag time) were predicted based on ComBase model and MFC physical-chemical aspects. Mean counts of Staphylococcus spp. ranged from 3.3 to 6.7 log cfu/g, indicating poor hygiene practices during production. Selected isolates (n = 10) were identified as S. aureus, but none presented classical enterotoxin-related genes. pH, temperature, and salt content ranged from 5.80 to 6.62, 5°C to 12°C, and 0.85% to 1.70%, respectively. The Grmax values ranged from 0.012 to 0.419 log cfu/g per h. Independent of the storage temperature, the lowest Grmax values (0.012 to 0.372 log cfu/h) were obtained at pH 5.80 associated with salt content of 1.7%; independent of the pH and salt content, the best temperature to avoid staphylococcal growth was 7.5°C. Hygienic conditions during MFC production must be adopted to avoid staphylococcal contamination, and storage at temperatures lower than 7.5°C can prevent staphylococcal growth and the potential production of enterotoxins.