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1.
Cytotherapy ; 2024 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-38639672

RESUMEN

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.

2.
J Dairy Sci ; 107(7): 5054-5069, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38460875

RESUMEN

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.


Asunto(s)
Acidosis , Alimentación Animal , Dieta , Pezuñas y Garras , Resistencia a la Insulina , Rumen , Animales , Bovinos , Rumen/metabolismo , Dieta/veterinaria , Pezuñas y Garras/patología , Acidosis/veterinaria , Enfermedades de los Bovinos , Masculino , Cojera Animal , Prueba de Tolerancia a la Glucosa/veterinaria
3.
Int J Mol Sci ; 25(11)2024 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-38892249

RESUMEN

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.


Asunto(s)
Trasplante de Células Madre Mesenquimatosas , Células Madre Mesenquimatosas , Medicina Regenerativa , Humanos , Células Madre Mesenquimatosas/citología , Células Madre Mesenquimatosas/metabolismo , Trasplante de Células Madre Mesenquimatosas/métodos , Medicina Regenerativa/métodos , Animales , Células Madre Pluripotentes Inducidas/citología , Diferenciación Celular
4.
BMC Cardiovasc Disord ; 23(1): 300, 2023 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-37322425

RESUMEN

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.


Asunto(s)
Intervención Coronaria Percutánea , Infarto del Miocardio con Elevación del ST , Humanos , Femenino , Infarto del Miocardio con Elevación del ST/diagnóstico por imagen , Infarto del Miocardio con Elevación del ST/terapia , Fibrinolíticos , Intervención Coronaria Percutánea/efectos adversos , Brasil/epidemiología , Benchmarking , Resultado del Tratamiento , Terapia Trombolítica/efectos adversos
5.
Cell Mol Life Sci ; 79(11): 568, 2022 Oct 26.
Artículo en Inglés | MEDLINE | ID: mdl-36287277

RESUMEN

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).


Asunto(s)
Antraciclinas , Cardiotoxicidad , Humanos , Antraciclinas/farmacología , Senoterapéuticos , Antibióticos Antineoplásicos , Senescencia Celular
6.
Adv Exp Med Biol ; 1418: 33-56, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37603271

RESUMEN

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.


Asunto(s)
Alostasis , Vesículas Extracelulares , Corazón , Transporte Biológico
7.
J Dairy Res ; 90(2): 186-190, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37338058

RESUMEN

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.


Asunto(s)
Queso , Animales , Cloruro de Calcio , Queso/análisis , Calcio
8.
Int J Mol Sci ; 24(13)2023 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-37445770

RESUMEN

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.


Asunto(s)
Envejecimiento , Mitocondrias Cardíacas , Ratones , Animales , Especies Reactivas de Oxígeno/metabolismo , Mitocondrias Cardíacas/metabolismo , Miocitos Cardíacos , Adenosina Trifosfato/metabolismo , Potencial de la Membrana Mitocondrial
9.
World J Microbiol Biotechnol ; 40(1): 3, 2023 Nov 04.
Artículo en Inglés | MEDLINE | ID: mdl-37923846

RESUMEN

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.


Asunto(s)
Queso , Pseudomonas , Pseudomonas/genética , Filogenia , Queso/análisis , Genómica , Fenotipo
10.
Cytotherapy ; 24(11): 1158-1165, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-35945103

RESUMEN

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.


Asunto(s)
Investigación Biomédica , Inversiones en Salud , Brasil , Tratamiento Basado en Trasplante de Células y Tejidos
11.
Cells Tissues Organs ; 211(4): 385-394, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-33040059

RESUMEN

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.


Asunto(s)
Ingeniería de Tejidos , Andamios del Tejido , Animales , Matriz Extracelular , Humanos , Hígado , Perfusión , Porcinos , Ingeniería de Tejidos/métodos
12.
Cardiovasc Drugs Ther ; 35(4): 719-732, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-33245463

RESUMEN

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.


Asunto(s)
Agonistas de los Canales de Calcio , Canales de Potasio de Gran Conductancia Activados por el Calcio , Hipertensión Arterial Pulmonar , Quinolinas/farmacología , Resistencia Vascular/efectos de los fármacos , Vasoconstricción/efectos de los fármacos , Vasodilatación/efectos de los fármacos , Animales , Agonistas de los Canales de Calcio/metabolismo , Agonistas de los Canales de Calcio/farmacocinética , Modelos Animales de Enfermedad , Canales de Potasio de Gran Conductancia Activados por el Calcio/agonistas , Canales de Potasio de Gran Conductancia Activados por el Calcio/metabolismo , Hipertensión Arterial Pulmonar/tratamiento farmacológico , Hipertensión Arterial Pulmonar/metabolismo , Hipertensión Arterial Pulmonar/fisiopatología , Ratas , Ratas Wistar , Resultado del Tratamiento , Remodelación Vascular/efectos de los fármacos , Función Ventricular Derecha/efectos de los fármacos
13.
Skin Res Technol ; 27(5): 676-681, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-33404160

RESUMEN

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.


Asunto(s)
Carcinoma Basocelular , Neoplasias Cutáneas , Carcinoma Basocelular/diagnóstico por imagen , Folículo Piloso , Humanos , Cirugía de Mohs , Neoplasias Cutáneas/diagnóstico por imagen , Ultrasonografía
14.
Mar Drugs ; 19(11)2021 Oct 23.
Artículo en Inglés | MEDLINE | ID: mdl-34822473

RESUMEN

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.


Asunto(s)
Bacillus , Edwardsiella tarda , Infecciones por Enterobacteriaceae/veterinaria , Enfermedades de los Peces/prevención & control , Peces , Probióticos , Animales , Acuicultura , Organismos Acuáticos , Infecciones por Enterobacteriaceae/prevención & control , Percepción de Quorum/efectos de los fármacos
15.
PLoS Genet ; 14(11): e1007770, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-30388103

RESUMEN

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.


Asunto(s)
Drosophila/clasificación , Drosophila/genética , Cromosoma Y/genética , Animales , Evolución Molecular , Femenino , Duplicación de Gen , Genes de Insecto , Ligamiento Genético , Masculino , Modelos Genéticos , Filogenia , Selección Genética , Especificidad de la Especie , Translocación Genética , Cromosoma X/genética
16.
J Dairy Sci ; 104(12): 12312-12320, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34593231

RESUMEN

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.


Asunto(s)
Queso , Animales , Brasil , Enterotoxinas/análisis , Enterotoxinas/genética , Microbiología de Alimentos , Staphylococcus , Staphylococcus aureus
17.
J Dairy Res ; 88(3): 343-350, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34289915

RESUMEN

The beneficial effects of a healthy diet on the quality of life have prompted the food industry to develop low-fat variants, but fat content directly affects the physicochemical and sensory properties of food products. The utilization of high-pressure homogenization (HP) and incorporation of hydrocolloids have been suggested as strategies to improve the physical stability and rheological properties of light cream. Thus, this study aims to analyze the associated effect of high-pressure homogenization (80 MPa) and three different hydrocolloids: microcrystalline cellulose, locust bean gum and xanthan gum, on emulsion stability and rheological properties of ultra-high-temperature (UHT) light cream (ULC) with a 15% w/w fat content. The stability of ULC was determined by the ζ potential of oil droplets and emulsion stability percentage. Rheological characterization was based on flow behavior tests and dynamic oscillatory measurements, which were carried out in a rheometer. Results showed that the high-pressure homogenization process did not influence the emulsion stability of the treatments. Moreover, the hydrocolloids added to systems present weak interactions with milk proteins since all ULC showed macroscopical phase separation. The samples presented the same rheological behavior and were classified as pseudoplastic fluids (n < 1). ULC treated at 80 MPa was significantly (P ≤ 0.05) more consistent than the treatments at 20 MPa. All ULC showed a predominant elastic behavior (G' > G″), and a remarkable increase in both G' and G″ at 80 MPa. The results presented in this study highlight the potential of HP for altering some rheological characteristics of UHT light cream, for example, to increase its consistency. These results are important for the dairy industry and ingredient suppliers, in the standardization of UHT light cream and/or to develop low-fat products.


Asunto(s)
Coloides/administración & dosificación , Productos Lácteos , Grasas de la Dieta/análisis , Manipulación de Alimentos/métodos , Calor , Leche/química , Animales , Celulosa , Fenómenos Químicos , Dieta con Restricción de Grasas , Emulsiones , Galactanos , Mananos , Gomas de Plantas , Polisacáridos Bacterianos , Presión , Reología
18.
J Dairy Res ; 88(4): 457-460, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34886919

RESUMEN

In this Research Communication we focus the food industry´s broad tendency to decrease sugar content in food products onto dulce de leche (DL) and examine the influence of sucrose reduction on the detrimental deposits formed during the production process. The method used to identify the impact produced directly on the heat exchanger during the production of this product with low sucrose content required varying the quantity of sucrose in the milk. Different percentages of sucrose (20, 15, 10, 5 and 0% w/w) were submitted to the DL concentration process in a process simulator. After concentration, the quantification of the deposits formed in each was carried out and these deposits were characterized according to their composition. Methods such as Kjeldahl, Pregl-Dumas and sem-EDS were used. Thus, the work highlights the need to change the product manufacturing process due to changes in the formulation that directly impact the formation of deposits in the equipment used (fouling). This deposit changes significantly in relation to its quantity as well as in relation to the composition and chemical characteristics as the gradual reduction of the sucrose content in the production takes place. Therefore, these impacts must be considered in order to maintain better manufacturing and ensure efficient cleaning of equipment.


Asunto(s)
Leche , Sacarosa , Animales , Carbohidratos
19.
Compr Rev Food Sci Food Saf ; 20(4): 3267-3283, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-34146458

RESUMEN

Lactic acid bacteria (LAB) cultures used in food fermentation are often dried to reduce transportation costs and facilitate handling during use. Dried LAB ferments are generally lyophilized to ensure high cell viability. Spray drying has come to the forefront as a promising technique due to its versatility and lower associated energy costs. Adverse conditions during spray drying, such as mechanical stress, dehydration, heating, and oxygen exposure, can lead to low LAB cell viability. This reduced viability has limited spray drying's industrial applications thus far. This review aims to demonstrate the operations and thermodynamic principles that govern spray drying, then correlate them to the damage suffered by LAB cells during the spray-drying process. The particularities of spray drying that might cause LAB cell death are detailed in this review, and the conclusion may enhance future studies on ways to improve cell viability.


Asunto(s)
Lactobacillales , Supervivencia Celular , Desecación , Microbiología de Alimentos , Secado por Pulverización
20.
Fish Physiol Biochem ; 47(5): 1541-1558, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34370152

RESUMEN

This study aimed at assessing the effects of the dietary tryptophan (Trp) supplementation on growth and feed utilization, brain serotonin content, and expression of selected liver genes (involved in the liver serotonin pathway, protein synthesis degradation, and antioxidant activity) in zebrafish. A growth trial was conducted with zebrafish juveniles fed five experimental isoproteic (40%DM) and isolipidic (8%DM) fishmeal-based diets containing graded levels of Trp: a Trp-non-supplemented diet (diet Trp0, with 0.22% Trp) and four Trp-supplemented diets containing 2-16 times higher Trp content (diets Trp2, Trp4, Trp8, and Trp16 with 0.40, 0.91, 2.02, and 3.34% Trp, respectively). Diets were tested in quadruplicate, with fish being fed twice a day, 6 days a week for 6 weeks to apparent visual satiation. At the end of the trial, growth performance and feed utilization were assessed, and fish from all experimental groups were sampled for whole-body composition analysis. In addition, fish fed low (Trp0), medium (Trp4), and high (Trp16) Trp diets were also sampled for analysis of brain serotonin content and liver gene expression. Tested tryptophan levels did not influence growth performance nor feed intake. However, values of energy and nitrogen retention as well as body energy content indicate a better feed utilization with diets containing around 0.9% and 2.0% DM Trp. Brain serotonin content increased with increasing dietary tryptophan levels. In addition, regarding liver genes, dietary treatment had a modulatory effect on the expression of Htr1aa and Htr2cl1 genes (encoding for serotonin receptors), TPH1a gene (encoding for tryptophan hydroxylase, the rate-limiting enzyme in the synthesis of serotonin from tryptophan), TOR gene (involved in protein synthesis), and Keap1 gene (involved in antioxidant responses).


Asunto(s)
Triptófano , Pez Cebra , Alimentación Animal/análisis , Animales , Antioxidantes , Encéfalo , Dieta/veterinaria , Suplementos Dietéticos , Proteína 1 Asociada A ECH Tipo Kelch , Hígado , Factor 2 Relacionado con NF-E2 , Serotonina , Triptófano/farmacología
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