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1.
Bol. latinoam. Caribe plantas med. aromát ; 23(4): 534-551, jul. 2024. ilus, tab, graf
Artigo em Espanhol | LILACS | ID: biblio-1538057

RESUMO

The cultural significance of the flora used by the native Asheninka Sheremashe community in Ucayali, Peru was determined. To do this, a fieldwork of over 4 months was conducted, involving semi-structured interviews with 106 residents through non-probabilistic convenience sampling. The community utilizes 139 plant species in their daily lives, belonging to 120 genera and 52 families, with the most abundant being Fabaceae, Arecaceae, Malvaceae, Solanaceae, Poaceae, and Rutaceae. Furthermore, 25.9% of the species are of significant importance to theinhabitants according to the Cultural Index (CI), such as Manihot esculenta, Theobroma cacao, Bixa orellana, Musa paradisiaca, Ficus insipida, among others. It can be concluded that the flora plays a prominent role in the life of the community, with the categories reporting the highest number of species being: food (29.35%), medicine (28.36%), culture (9.95%), construction (9.45%), lumber (6.97%), commerce (3.48%), craftsmanship (2.49%), toxic (2.49%), and other uses (7.46%)


Se determinó la importancia cultural de la flora empleada por la comunidad nativa Asheninka Sheremashe, en Ucayali, Perú. Para ello, se realizó un trabajo de campo de más de 4 meses, donde se aplicaron entrevistas semiestructuradas a 106 habitantes mediante un muestreo no probabilístico por conveniencia. La comunidad emplea 139 especies vegetales en su día a día, pertenecientes a 120 géneros y 52 familias; siendo las más abundantes las Fabaceae, Arecaceae, Malvaceae, Solanaceae, Poaceae y Rutaceae. Además, el 25.9% de las especies tiene gran importancia para los pobladores según el Índice Cultural (IC): Manihot esculenta, Theobroma cacao, Bixa orellana, Musa paradisiaca, Ficus insipida, entre otras. Se concluye que la flora tiene un rol preponderante en la vida de la comunidad, siendo las categorías que presentaron mayor reporte de especies: alimentación (29.35%), medicina (28.36%), cultura (9.95%), construcción (9.45%), aserrío (6.97%), comercio (3.48%), artesanía (2.49%), tóxico (2.49%) y otros usos (7.46%)


Assuntos
Etnobotânica , Medicina Tradicional , Peru , Inquéritos e Questionários , Flora , Medicina Herbária
2.
Molecules ; 29(7)2024 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-38611933

RESUMO

Few sclerophyllous plants from the central coast of Chile have been systematically studied. This work describes the phytochemical composition and antimicrobial properties of Baccharis concava Pers. (sin. B. macraei), a shrub found in the first line and near the Pacific coast. B. concava has been traditionally used by indigenous inhabitants of today's central Chile for its medicinal properties. Few reports exist regarding the phytochemistry characterization and biological activities of B. concava. A hydroalcoholic extract of B. concava was prepared from leaves and small branches. Qualitative phytochemical characterization indicated the presence of alkaloids, steroids, terpenoids, flavonoids, phenolic, and tannin compounds. The antimicrobial activity of this extract was assessed in a panel of microorganisms including Gram-positive bacteria, Gram-negative bacteria, and pathogenic yeasts. The extract displayed an important antimicrobial effect against Gram-positive bacteria, Candida albicans, and Cryptococcus neoformans but not against Gram-negatives, for which an intact Lipopolysaccharide is apparently the determinant of resistance to B. concava extracts. The hydroalcoholic extract was then fractionated through a Sephadex LH-20/methanol-ethyl acetate column. Afterward, the fractions were pooled according to a similar pattern visualized by TLC/UV analysis. Fractions obtained by this criterion were assessed for their antimicrobial activity against Staphylococcus aureus. The fraction presenting the most antimicrobial activity was HPLC-ESI-MS/MS, obtaining molecules related to caffeoylquinic acid, dicaffeoylquinic acid, and quercetin, among others. In conclusion, the extracts of B. concava showed strong antimicrobial activity, probably due to the presence of metabolites derived from phenolic acids, such as caffeoylquinic acid, and flavonoids, such as quercetin, which in turn could be responsible for helping with wound healing. In addition, the development of antimicrobial therapies based on the molecules found in B. concava could help to combat infection caused by pathogenic yeasts and Gram-positive bacteria, without affecting the Gram-negative microbiota.


Assuntos
Baccharis , Quercetina , Ácido Quínico/análogos & derivados , Chile , Espectrometria de Massas em Tandem , Compostos Fitoquímicos/farmacologia , Flavonoides/farmacologia , Extratos Vegetais/farmacologia
3.
Vaccine ; 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38627145

RESUMO

The head domain of the hemagglutinin of influenza viruses plays a dominant role in the antibody response due to the presence of immunodominant antigenic sites that are the main targets of host neutralizing antibodies. For the H1 hemagglutinin, five major antigenic sites defined as Sa, Sb, Ca1, Ca2, and Cb have been described. Although previous studies have focused on defining the hierarchy of the antigenic sites of the hemagglutinin in different human cohorts, it is still unclear if the immunodominance profile of the antigenic sites might change with the antibody levels of individuals or if other demographic factors (such as exposure history, sex, or age) could also influence the importance of the antigenic sites. The major antigenic sites of influenza viruses hemagglutinins are responsible for eliciting most of the hemagglutination inhibition antibodies in the host. To determine the antibody prevalence towards each major antigenic site, we evaluated the hemagglutination inhibition against a panel of mutant H1 viruses, each one lacking one of the "classic" antigenic sites. Our results showed that the individuals from the Stop Flu NYU cohort had an immunodominant response towards the sites Sb and Ca2 of H1 hemagglutinin. A simple logistic regression analysis of the immunodominance profiles and the hemagglutination inhibition titers displayed by each donor revealed that individuals with high hemagglutination inhibition titers against the wild-type influenza virus exhibited higher probabilities of displaying an immunodominance profile dominated by Sb, followed by Ca2 (Sb > Ca2 profile), while individuals with low hemagglutination inhibition titers presented a higher chance of displaying an immunodominance profile in which Sb and Ca2 presented the same level of immunodominance (Sb = Ca2 profile). Finally, while age exhibited an influence on the immunodominance of the antigenic sites, biological sex was not related to displaying a specific immunodominance profile.

4.
J Pers ; 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38416715

RESUMO

OBJECTIVE: Spiteful behaviors are those aimed at inflicting harm on another person while also incurring a cost to the self. Although spite sometimes reflects destructive and socially undesirable behaviors including aggression, the current work sought to examine a potentially socially beneficial aspect of spite: engagement in costly punishment for selfish behavior. METHOD: Four studies used a costly third-party punishment task and measured individual differences in spite, narcissism, Machiavellianism, psychopathy, and motivations for engaging in punishment. RESULTS: Trait spite was positively associated with costly punishment of selfish behavior. That association was independent of other dark personality traits (narcissism, Machiavellianism, psychopathy) and was statistically mediated by a desire for retribution. One of the studies also provided evidence that trait spite was associated with costly punishment of even generous behavior; however, rather than a desire for retribution, that association was mediated by a desire to threaten the person being punished. CONCLUSION: Punishing selfishness and other forms of wrongdoing plays an essential role in cooperative group living. The current work provides new insight into the role spiteful motivations might play in this crucial social behavior.

5.
Front Cell Neurosci ; 18: 1341141, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38357436

RESUMO

Introduction: Down syndrome, caused by trisomy 21, is a complex developmental disorder associated with intellectual disability and reduced growth of multiple organs. Structural pathologies are present at birth, reflecting embryonic origins. A fundamental unanswered question is how an extra copy of human chromosome 21 contributes to organ-specific pathologies that characterize individuals with Down syndrome, and, relevant to the hallmark intellectual disability in Down syndrome, how trisomy 21 affects neural development. We tested the hypothesis that trisomy 21 exerts effects on human neural development as early as neural induction. Methods: Bulk RNA sequencing was performed on isogenic trisomy 21 and euploid human induced pluripotent stem cells (iPSCs) at successive stages of neural induction: embryoid bodies at Day 6, early neuroectoderm at Day 10, and differentiated neuroectoderm at Day 17. Results: Gene expression analysis revealed over 1,300 differentially expressed genes in trisomy 21 cells along the differentiation pathway compared to euploid controls. Less than 5% of the gene expression changes included upregulated chromosome 21 encoded genes at every timepoint. Genes involved in specific growth factor signaling pathways (WNT and Notch), metabolism (including oxidative stress), and extracellular matrix were altered in trisomy 21 cells. Further analysis uncovered heterochronic expression of genes. Conclusion: Trisomy 21 impacts discrete developmental pathways at the earliest stages of neural development. The results suggest that metabolic dysfunction arises early in embryogenesis in trisomy 21 and may affect development and function more broadly.

6.
J Anim Ecol ; 93(4): 393-405, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38100230

RESUMO

Comprehending symbiont abundance among host species is a major ecological endeavour, and the metabolic theory of ecology has been proposed to understand what constrains symbiont populations. We parameterized metabolic theory equations to investigate how bird species' body size and the body size of their feather mites relate to mite abundance according to four potential energy (uropygial gland size) and space constraints (wing area, total length of barbs and number of feather barbs). Predictions were compared with the empirical scaling of feather mite abundance across 106 passerine bird species (26,604 individual birds sampled), using phylogenetic modelling and quantile regression. Feather mite abundance was strongly constrained by host space (number of feather barbs) but not by energy. Moreover, feather mite species' body size was unrelated to the body size of their host species. We discuss the implications of our results for our understanding of the bird-feather mite system and for symbiont abundance in general.


Assuntos
Doenças das Aves , Infestações por Ácaros , Ácaros , Passeriformes , Animais , Filogenia , Tamanho Corporal , Infestações por Ácaros/veterinária
7.
Mar Environ Res ; 194: 106312, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38150786

RESUMO

The richness of plankton communities determines the fish productivity in the ocean, including important resources that rely on extractive fisheries, such as hakes (genus Merluccius) and tunas (genus Thunnus). Their preys forage on zooplankton, and the latter feed on phytoplankton. Inventories of plankton communities for scientific advice to sustainable fishing are essential in this moment of climate change. Plankton is generally inventoried using conventional methodologies based on large water volumes and visual morphological analyses of samples. In this study, we have employed metabarcoding on environmental DNA (eDNA) samples extracted from small water volumes for plankton inventory from twelve distant sampling stations in the East Atlantic Ocean. Zones rich in hake and tuna prey were detected from eDNA, and multivariate multiple regression analysis was able to predict those zones from diatom-based indices and planktonic diversity based on functional groups. Salinity was negatively correlated with the proportion of diatoms in phytoplankton, highlighting expected impacts of current global change on marine plankton communities. The results emphasise the importance of the plankton richness for fish productivity and support the utility of environmental DNA as a tool to monitor plankton composition changes.


Assuntos
DNA Ambiental , Diatomáceas , Animais , Plâncton , Atum , Fitoplâncton/genética , Água , Ecossistema
8.
Metab Eng Commun ; 18: e00229, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38098801

RESUMO

Saccharomyces cerevisiae has been conveniently used to produce Taxol® anticancer drug early precursors. However, the harmful impact of oxidative stress by the first cytochrome P450-reductase enzymes (CYP725A4-POR) of Taxol® pathway has hampered sufficient progress in yeast. Here, we evolved an oxidative stress-resistant yeast strain with three-fold higher titre of their substrate, taxadiene. The performance of the evolved and parent strains were then evaluated in galactose-limited chemostats before and under the oxidative stress by an oxidising agent. The interaction of evolution and oxidative stress was comprehensively evaluated through transcriptomics and metabolite profiles integration in yeast enzyme-constrained genome scale model. Overall, the evolved strain showed improved respiration, reduced overflow metabolites production and oxidative stress re-induction tolerance. The cross-protection mechanism also potentially contributed to better heme, flavin and NADPH availability, essential for CYP725A4 and POR optimal activity in yeast. The results imply that the evolved strain is a robust cell factory for future efforts towards Taxol© production.

9.
Inorg Chem ; 62(48): 19741-19748, 2023 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-38044828

RESUMO

Magnetic refrigeration based on the magnetocaloric effect (MCE) in metal-organic frameworks (MOF) is regarded as an attractive approach to create more sustainable cooling systems with higher efficiency than traditional ones. Here, we report a study of the MCE in a series of rare-earth-based MOFs. We have considered the selection of the rare-earth cation by investigating materials belonging to the α-rare-earth polymeric framework-4 (α-RPF-4) MOF family, synthesized with different rare-earth cations, and observed that paramagnetic moment and saturation magnetization play an important role in enhancing the magnetic entropy change ΔSM. The effect of structural parameters has also been considered by investigating three classes of metal-organic Gd materials built up from different types of inorganic secondary building units, including clusters (as in Gd-UiO-66), one-dimensional (as in α-RPF-4), and layered (as in Gd-LRH) conformations. Moreover, the analysis of the hydrostatic pressure influence reveals a significant increase in the -ΔSM and relative cooling power (RCP) with values between 4.3 and 16.3 and 121-509 J/kg. Specifically, the RCPmax found was ∼683 J/kg for Gd-UiO-66, which is higher than the one recently observed for Gd2SiO5 (649.5 J/kg). The present study demonstrates that the engineering of metal-organic framework systems based on high Gd densities may favor enhancing of magnetocaloric responses even at low pressures, thus promoting a new design strategy for efficient cooling devices.

10.
Pers Soc Psychol Bull ; : 1461672231216821, 2023 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-38146692

RESUMO

Models of adaptive calibration provide an overarching theoretical framework for understanding the developmental roots of psychological and behavioral outcomes in adulthood. An adaptive calibration framework was used to examine an important dimension of motivation: goal timing. Across two studies, we saw mixed support for the hypothesis that unpredictability experienced in childhood would be negatively associated with the time horizons people use to set their goals, such that people who reported experiencing more unpredictability in their childhood tended to set goals on relatively shorter time horizons. The association was observed based on independent ratings of goal timing, but not based on participants' self-reported ratings of goal timing, and was statistically mediated by people's tendency to consider the short- versus long-term future consequences of their actions. These studies isolate a key component of childhood adversity-unpredictability-potentially underlying the time horizons people use to set, prioritize, and pursue their goals.

11.
Wound Repair Regen ; 31(6): 745-751, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37955618

RESUMO

The current study aimed to evaluate the dispersal of solution and microbes (aerosol) in the clinical environment during treatment with Low-frequency contact ultrasonic debridement (LFCUD) with or without suction attachment in patients with diabetic foot ulcers (DFUs). We performed 20 treatments in 10 patients divided into two groups to receive the proposed LFCUD modalities. We measured the microbial load of the environment pre-treatment (sample M1), during treatment with each LFCUD modality (sample M2) and post-treatment (sample M3). The use of LFCUD debridement without a suction attachment results in significantly higher immediate contamination of the clinic environment than the suction attachment, particularly during the procedure (1.70 ± 0.98 log 10 CFU/mL versus 0.77 ± 0.85 log 10 CFU/mL, p = 0.035). When suction is not applied, there are statistically significant differences depending on whether the DFUs are neuropathic or neuroischemic, finding a greater number of microorganisms with high loads in neuropathic DFUs. We found a statistically significant positive correlation between wound area (r = 0.450, p = 0.047) and TBI (r = 0.651, p = 0.006) with the bacterial load during the LFCUD. Based on our results, we recommend using the personal protective equipment required to protect staff members and patients during treatment with LFCUD and using a suction attachment where clinically possible to reduce clinic environmental pollution, especially in neuropathic DFUs and those with larger areas.


Assuntos
Diabetes Mellitus , Pé Diabético , Humanos , Pé Diabético/terapia , Desbridamento/métodos , Cicatrização , Ultrassom , Carga Bacteriana
12.
Trop Anim Health Prod ; 55(6): 381, 2023 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-37884761

RESUMO

The effects of intramammary dry cow therapy based on the administration of 5% Melaleuca alternifolia tea tree essential oil (TTO) as an internal teat sealant to Murrah cows were evaluated. A longitudinal prospective and retrospective negative control study was performed using 12 buffaloes from a total of 20 Murrah buffaloes on an organic farm, with the cow used as a control for herself. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) for treatments with pure oil (TTO) and medication containing 5% TTO (O5) were determined. The buffaloes were clinically examined, and the teats were evaluated using thermography and ultrasound. Udder health was monitored during the first 100 days in milk (DIM) using milk somatic cell count (SCC) and California mastitis test (CMT). Laboratory tests against standard strains Staphylococcus aureus ATCC®25,923™, Escherichia coli ATCC®25,922™, and wild bacterial strains showed maximum MIC values of 50 µL/mL for the TTO and O5 treatments. One wild-type S. aureus strain showed no MBC. No adverse effects were observed after the intramammary application of TTO. The CMT and SCC values were similar (P > 0.05) for all observations. The medication containing 5% TTO was effective in vitro and compatible with the intramammary tissue in vivo of Murrah buffaloes. TTO was safe, not inducing inflammatory processes or other modifications of the teat detectable by thermography or ultrasound. It was able to protect buffaloes during the dry period under field conditions, demonstrating potential use as a teat sealant for organic farms.


Assuntos
Doenças dos Bovinos , Mastite Bovina , Melaleuca , Feminino , Bovinos , Animais , Antibacterianos/farmacologia , Lactação , Búfalos , Staphylococcus aureus , Estudos Prospectivos , Estudos Retrospectivos , Leite/microbiologia , Glândulas Mamárias Animais/microbiologia , Mastite Bovina/microbiologia , Contagem de Células/veterinária , Doenças dos Bovinos/tratamento farmacológico
13.
N Biotechnol ; 78: 105-115, 2023 Dec 25.
Artigo em Inglês | MEDLINE | ID: mdl-37848161

RESUMO

The halotolerant non-conventional yeast Debaryomyces hansenii can grow in media containing high concentrations of salt (up to 4 M), metabolize alternative carbon sources than glucose, such as lactose or glycerol, and withstand a wide range of temperatures and pH. These inherent capabilities allow this yeast to grow in harsh environments and use alternative feedstock than traditional commercial media. For example, D. hansenii could be a potential cell factory for revalorizing industrial salty by-products, using them as a substrate for producing new valuable bioproducts, boosting a circular economy. In this work, three different salty by-products derived from the dairy and biopharmaceutical industry have been tested as a possible feedstock for D. hansenii's growth. The yeast was not only able to grow efficiently in all of them but also to produce a recombinant protein (Yellow Fluorescent Protein, used as a model) without altering its performance. Moreover, open cultivations at different laboratory scales (1.5 mL and 1 L) were performed under non-sterile conditions and without adding fresh water or any nutritional supplement to the cultivation, making the process cheaper and more sustainable.


Assuntos
Debaryomyces , Saccharomycetales , Debaryomyces/metabolismo , Saccharomyces cerevisiae/metabolismo , Rios , Cloreto de Sódio , Proteínas Recombinantes/metabolismo , Saccharomycetales/metabolismo
14.
ACS Appl Mater Interfaces ; 15(43): 50290-50301, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37862555

RESUMO

Transition-metal chalcogenides with intercalated layered structures are interesting systems in material physics due to their attractive electronic and magnetic properties, with applications in the fields of magnetic refrigerators, catalysts, and thermoelectrics, among others. In this work, we studied in detail the structural, electronic, and magnetic properties of (Fe,Ti)-based sulfides with formula FexTi2S4 (x = 0.24, 0.32, and 0.42), prepared as polycrystalline materials under high-pressure conditions. They present a layered Heideite-type crystal structure, as assessed by synchrotron X-ray diffraction. A local structure analysis using Fe K-edge extended X-ray-absorption fine structure (EXAFS) data unveiled a conspicuous contraction of the main Fe-S bond in Fe0.24Ti2S4 at the vicinity of the magnetic transition 60-80 K. We suggest that this anomaly is related to magnetoelastic coupling effects. The EXAFS analysis allowed extraction of the Einstein temperatures (θE), i.e., the phonon contribution to the specific heat, for the two bond pairs Fe-S(1) [θE ≈318 K; 290 K (C/T)] and Fe-Ti(1) [θE ≈218 K; 190 K (C/T)]. In addition to the structural and local vibrational measurements, we probed the magnetic properties using magneto-calorimetry, magnetometry under applied pressure, magnetoresistance (MR), and Hall effect measurements. We observed the appearance of a broad peak in the specific heat around 120 K in the x = 0.42 compound that we associated with an antiferromagnetic ordering electronic transition. We found that the antiferromagnetic transition temperature is pressure and composition sensitive and reduces at 1.2 GPa by ∼12 and ∼3 K, for the members with x = 0.24 and x = 0.42, respectively. Similarly, the saturation magnetization in the ordered phase depends on both pressure and iron content, reducing its value by 50, 90, and 30% for x = 0.24, 0.32, and 0.42, respectively. We observed clear jumps in the magnetic hysteresis loops, MR, and anomalous Hall effect (AHE) below 2 K at fields around 2-4 T. We associated this observation with the metamagnetic transitions; from the Berry-curvature a decoupling parameter of SH = 0.12 V-1 is determined. Comparison of the results on the temperature-dependent magnetization, MR, and AHE elucidates a strong inelastic scattering contribution to the AHE at higher temperatures due to the cluster spin-glass phase.

16.
Int J Mol Sci ; 24(15)2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37569678

RESUMO

Pseudomonas aeruginosa is a ubiquitous nosocomial opportunistic pathogen that harbors many virulence determinants. Part of P. aeruginosa success colonizing a variety of habitats resides in its metabolic robustness and plasticity, which are the basis of its capability of adaptation to different nutrient sources and ecological conditions, including the infected host. Given this situation, it is conceivable that P. aeruginosa virulence might be, at least in part, under metabolic control, in such a way that virulence determinants are produced just when needed. Indeed, it has been shown that the catabolite repression control protein Crc, which together with the RNA chaperon Hfq regulates the P. aeruginosa utilization of carbon sources at the post-transcriptional level, also regulates, directly or indirectly, virulence-related processes in P. aeruginosa. Among them, Crc regulates P. aeruginosa cytotoxicity, likely by modulating the activity of the Type III Secretion System (T3SS), which directly injects toxins into eukaryotic host cells. The present work shows that the lack of Crc produces a Type III Secretion-defective phenotype in P. aeruginosa. The observed impairment is a consequence of a reduced expression of the genes encoding the T3SS, together with an impaired secretion of the proteins involved. Our results support that the impaired T3SS activity of the crc defective mutant is, at least partly, a consequence of a defective protein export, probably due to a reduced proton motive force. This work provides new information about the complex regulation of the expression and the activity of the T3SS in P. aeruginosa. Our results highlight the need of a robust bacterial metabolism, which is defective in the ∆crc mutant, to elicit complex and energetically costly virulence strategies, as that provided by the T3SS.


Assuntos
Pseudomonas aeruginosa , Sistemas de Secreção Tipo III , Sistemas de Secreção Tipo III/genética , Sistemas de Secreção Tipo III/metabolismo , Virulência/genética , Pseudomonas aeruginosa/metabolismo , Fatores de Virulência/metabolismo , Fenômenos Fisiológicos Celulares , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Regulação Bacteriana da Expressão Gênica
17.
Microb Biotechnol ; 16(10): 1900-1923, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37417823

RESUMO

As recognized by several international agencies, antibiotic resistance is nowadays one of the most relevant problems for human health. While this problem was alleviated with the introduction of new antibiotics into the market in the golden age of antimicrobial discovery, nowadays few antibiotics are in the pipeline. Under these circumstances, a deep understanding on the mechanisms of emergence, evolution and transmission of antibiotic resistance, as well as on the consequences for the bacterial physiology of acquiring resistance is needed to implement novel strategies, beyond the development of new antibiotics or the restriction in the use of current ones, to more efficiently treat infections. There are still several aspects in the field of antibiotic resistance that are not fully understood. In the current article, we make a non-exhaustive critical review of some of them that we consider of special relevance, in the aim of presenting a snapshot of the studies that still need to be done to tackle antibiotic resistance.


Assuntos
Anti-Infecciosos , Farmacorresistência Bacteriana , Humanos , Antibacterianos/farmacologia
18.
Microb Cell Fact ; 22(1): 109, 2023 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-37287064

RESUMO

The probiotic yeast Saccharomyces boulardii (Sb) is a promising chassis to deliver therapeutic proteins to the gut due to Sb's innate therapeutic properties, resistance to phage and antibiotics, and high protein secretion capacity. To maintain therapeutic efficacy in the context of challenges such as washout, low rates of diffusion, weak target binding, and/or high rates of proteolysis, it is desirable to engineer Sb strains with enhanced levels of protein secretion. In this work, we explored genetic modifications in both cis- (i.e. to the expression cassette of the secreted protein) and trans- (i.e. to the Sb genome) that enhance Sb's ability to secrete proteins, taking a Clostridioides difficile Toxin A neutralizing peptide (NPA) as our model therapeutic. First, by modulating the copy number of the NPA expression cassette, we found NPA concentrations in the supernatant could be varied by sixfold (76-458 mg/L) in microbioreactor fermentations. In the context of high NPA copy number, we found a previously-developed collection of native and synthetic secretion signals could further tune NPA secretion between 121 and 463 mg/L. Then, guided by prior knowledge of S. cerevisiae's secretion mechanisms, we generated a library of homozygous single gene deletion strains, the most productive of which achieved 2297 mg/L secretory production of NPA. We then expanded on this library by performing combinatorial gene deletions, supplemented by proteomics experiments. We ultimately constructed a quadruple protease-deficient Sb strain that produces 5045 mg/L secretory NPA, an improvement of > tenfold over wild-type Sb. Overall, this work systematically explores a broad collection of engineering strategies to improve protein secretion in Sb and highlights the ability of proteomics to highlight under-explored mediators of this process. In doing so, we created a set of probiotic strains that are capable of delivering a wide range of protein titers and therefore furthers the ability of Sb to deliver therapeutics to the gut and other settings to which it is adapted.


Assuntos
Probióticos , Saccharomyces boulardii , Saccharomyces , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Saccharomyces boulardii/genética , Saccharomyces boulardii/metabolismo , Saccharomyces/genética , Saccharomyces/metabolismo , Probióticos/metabolismo , Endopeptidases/metabolismo
19.
Ophthalmic Plast Reconstr Surg ; 39(6): e184-e186, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37338339

RESUMO

A 20-year-old male presented with a fast-growing nodule in his right inferior eyelid, no relevant history was obtained. Final histopathologic diagnosis of primary cutaneous follicle center lymphoma (CD20+, CD10+, bcl6+, bcl10+, mum1+, PAX5+, and bcl2-) was determined. The patient had a complete negative systemic work-up, and 3 cycles of consisting of rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone chemotherapy were completed. The initial histopathologic diagnosis had been a non-Hodgkin diffuse large B-cell lymphoma which is an infrequent lymphoma type for this location too. To our knowledge, this is the youngest person reported presenting with an eyelid primary cutaneous follicle center lymphoma.


Assuntos
Linfoma Difuso de Grandes Células B , Masculino , Humanos , Adulto Jovem , Adulto , Prednisona/uso terapêutico , Linfoma Difuso de Grandes Células B/diagnóstico , Rituximab/uso terapêutico , Vincristina/uso terapêutico , Ciclofosfamida/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico
20.
Nanomaterials (Basel) ; 13(10)2023 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-37242018

RESUMO

The inclusion of La-Mn vacancies in LaMnO3 nanoparticles leads to a noticeable change in conductivity behavior. The sample retains its overall insulator characteristic, with a typical thermal activation mechanism at high temperatures, but it presents high magnetoconductivity below 200 K. The activation energy decreases linearly with the square of the reduced magnetization and vanishes when the sample is magnetized at saturation. Therefore, it turns out that electron hopping between Mn3+ and Mn4+ largely contributes to the conductivity below the Curie temperature. The influence of the applied magnetic field on conductivity also supports the hypothesis of hopping contribution, and the electric behavior can be explained as being due to an increase in the hopping probability via spin alignment.

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