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1.
Toxins (Basel) ; 16(5)2024 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-38787076

RESUMO

Kunitz-type peptide expression has been described in the venom of snakes of the Viperidae, Elapidae and Colubridae families. This work aimed to identify these peptides in the venom gland transcriptome of the coral snake Micrurus mipartitus. Transcriptomic analysis revealed a high diversity of venom-associated Kunitz serine protease inhibitor proteins (KSPIs). A total of eight copies of KSPIs were predicted and grouped into four distinctive types, including short KSPI, long KSPI, Kunitz-Waprin (Ku-WAP) proteins, and a multi-domain Kunitz-type protein. From these, one short KSPI showed high identity with Micrurus tener and Austrelaps superbus. The long KSPI group exhibited similarity within the Micrurus genus and showed homology with various elapid snakes and even with the colubrid Pantherophis guttatus. A third group suggested the presence of Kunitz domains in addition to a whey-acidic-protein-type four-disulfide core domain. Finally, the fourth group corresponded to a transcript copy with a putative 511 amino acid protein, formerly annotated as KSPI, which UniProt classified as SPINT1. In conclusion, this study showed the diversity of Kunitz-type proteins expressed in the venom gland transcriptome of M. mipartitus.


Assuntos
Cobras Corais , Venenos Elapídicos , Perfilação da Expressão Gênica , Transcriptoma , Animais , Cobras Corais/genética , Venenos Elapídicos/genética , Venenos Elapídicos/química , Sequência de Aminoácidos , Simulação por Computador , Serpentes Peçonhentas
2.
Nutr Hosp ; 2024 Feb 08.
Artigo em Espanhol | MEDLINE | ID: mdl-38450493

RESUMO

AIM: assess the prescription of oral nutritional supplements (ONS) in the Northern Area of Gran Canaria in the period 2016-2021. MATERIALS AND METHODS: based on electronic prescription data, the first ONS prescription during 2016-2021 was analyzed considering age, gender, nutritional requirements (NR), body mass index (BMI), percentage of weight loss (%WL), albumin and number of prescribed ONS per patient. RESULTS: 10,595 prescriptions were identified corresponding to 6661 patients with the following characteristics: 46.3 % men, mean age 72.84 ± 15.93 years, BMI 20.60 ± 3.98 kg/m2, %WL 11.89 ± 8.32 %; albumin 3.08 ± 0.63 g/dl. The most frequent etiologies of DRE were: neoplasms 42.6 %; degenerative processes of the CNS 28.9 %; stroke 3.9 %; short intestine 6.9 %, and inflammatory bowel disease (IBD) 5.5 %. The percentages of NR covered by the prescribed ONS were: 100 % in 8.9 % of cases, 50 % in 36.9 %, and 25 % in 54.2 %; 40.4 % of patients received 1 unit of ONS daily, 36.3 % took 2 units of ONS, and 23 % received > 3 units of ONS per day. Greater NR were associated with a greater number of ONS (p < 0.001), but 40.8 % of patients who needed to cover > 50 % of NR received only one unit of ONS. CONCLUSION: a significant percentage of patients with DRM do not receive a number of ONS according to their NR.

3.
Angew Chem Int Ed Engl ; 62(34): e202306274, 2023 08 21.
Artigo em Inglês | MEDLINE | ID: mdl-37338464

RESUMO

Tumor Necrosis Factor-α (TNF-α) is a cytokine that is normally produced by immune cells when fighting an infection. But, when too much TNF-α is produced as in autoimmune diseases, this leads to unwanted and persistent inflammation. Anti-TNF-α monoclonal antibodies have revolutionized the therapy of these disorders by blocking TNF-α and preventing its binding to TNF-α receptors, thus suppressing the inflammation. Herein, we propose an alternative in the form of molecularly imprinted polymer nanogels (MIP-NGs). MIP-NGs are synthetic antibodies obtained by nanomoulding the 3-dimensional shape and chemical functionalities of a desired target in a synthetic polymer. Using an in-house developed in silico rational approach, epitope peptides of TNF-α were generated and 'synthetic peptide antibodies' were prepared. The resultant MIP-NGs bind the template peptide and recombinant TNF-α with high affinity and selectivity, and can block the binding of TNF-α to its receptor. Consequently they were applied to neutralize pro-inflammatory TNF-α in the supernatant of human THP-1 macrophages, leading to a downregulation of the secretion of pro-inflammatory cytokines. Our results suggest that MIP-NGs, which are thermally and biochemically more stable and easier to manufacture than antibodies, and cost-effective, are very promising as next generation TNF-α inhibitors for the treatment of inflammatory diseases.


Assuntos
Impressão Molecular , Polímeros Molecularmente Impressos , Humanos , Nanogéis , Fator de Necrose Tumoral alfa , Inibidores do Fator de Necrose Tumoral , Anticorpos/metabolismo , Peptídeos/farmacologia , Macrófagos/metabolismo , Inflamação/tratamento farmacológico , Impressão Molecular/métodos
4.
Artigo em Inglês | MEDLINE | ID: mdl-37183473

RESUMO

INTRODUCTION: Chia (Salvia hispanica L.) is a plant from the Lamiaceae family that has been used as ancestral food, medicine, and oil, with culinary, artistic, and religious purposes by most of the Mesoamerican civilizations. Native from Mesoamerica, introduced into South America, Australia, and Europe, it is presently consumed as a nutritional and functional food. OBJECTIVE: This research aims to characterize ancient native cultivars from four provenances in Guatemala to recommend their direct consumption by the population as well as to establish its trade. METHOD: Seed samples were collected in four places where they have been cultivated for several generations. The oil was obtained by expression and analyzed chemically by gas chromatography following standard qualitative and quantitative methods. RESULTS: Variations in oil yield and some of the characteristic parameters of the phytochemical analysis were obtained. In general, the profile was similar to most of the reported data in the literature, with the saturated fatty acids (8.54-9.25%) relatively lower than the references (7.95-11.45%) but a higher concentration of unsaturated fatty oils, particularly of omega-3 (64.68-68.62%). CONCLUSION: The oil from native cultivars contains high quantities of omega-3, which might help pregnant women during gestation and to control other conditions such as metabolic syndrome, particularly in low- and middle-income populations where these seeds are consumed regularly. The suggestion is made to encourage the cultivation and use of these ancestral seeds with the possibility of commercialization abroad with an appellation of origin label.

5.
Int J Mol Sci ; 24(2)2023 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-36674597

RESUMO

Dupuytren's contracture (DC) is a chronic and progressive fibroproliferative disorder restricted to the palmar fascia of the hands. Previously, we discovered the presence of high levels of connective tissue growth factor in sweat glands in the vicinity of DC nodules and hypothesized that sweat glands have an important role in the formation of DC lesions. Here, we shed light on the role of sweat glands in the DC pathogenesis by proteomic analysis and immunofluorescence microscopy. We demonstrated that a fraction of sweat gland epithelium underwent epithelial-mesenchymal transition illustrated by negative regulation of E-cadherin. We hypothesized that the increase in connective tissue growth factor expression in DC sweat glands has both autocrine and paracrine effects in sustaining the DC formation and inducing pathological changes in DC-associated sweat glands.


Assuntos
Contratura de Dupuytren , Humanos , Contratura de Dupuytren/metabolismo , Contratura de Dupuytren/patologia , Fator de Crescimento do Tecido Conjuntivo/metabolismo , Transição Epitelial-Mesenquimal , Proteômica , Fáscia/metabolismo
6.
Biochem Biophys Res Commun ; 642: 97-106, 2023 01 29.
Artigo em Inglês | MEDLINE | ID: mdl-36566568

RESUMO

As in other mammalian tissues, the extracellular matrix (ECM) of skin functions as mechanical support and regulative environment that guides the behavior of the cells. ECM is a gel-like structure that is primarily composed of structural and nonstructural proteins. While the content of structural proteins is stable, the level of nonstructural ECM proteins, such as thrombospondin-4 (THBS4), is dynamically regulated. In a previous work we demonstrated that THBS4 stimulated cutaneous wound healing. In this work we discovered that in addition to proliferation, THBS4 stimulated the migration of primary keratinocytes in 3D. By using a proteotransciptomic approach we found that stimulation of keratinocytes with THBS4 regulated the activity of signaling pathways linked to proliferation, migration, inflammation and differentiation. Interestingly, some of the regulated genes (eg IL37, TSLP) have been associated with the pathogenesis of atopic dermatitis (AD). We concluded that THBS4 is a promising candidate for novel wound healing therapies and suggest that there is a potential convergence of pathways that stimulate cutaneous wound healing with those active in the pathogenesis of inflammatory skin diseases.


Assuntos
Queratinócitos , Pele , Animais , Humanos , Proliferação de Células , Inflamação/patologia , Interleucina-1/metabolismo , Queratinócitos/metabolismo , Mamíferos , Pele/metabolismo , Trombospondinas/metabolismo
7.
Hypertens Res ; 46(1): 219-225, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36229533

RESUMO

In order to assess the risk of hypertension development, we performed a retrospective analysis of the clinical records of consecutive transgender patients who began gender-affirming hormonal therapy in our Outpatient Gender Identity Clinic with <30 years of age and had a follow-up >5 years. 149 transgender women treated with estradiol and 153 transgender men treated with testosterone were included; 129 of the transgender women received also androgen blockers (54 spironolactone, 49 cyproterone acetate and 26 LHRH agonists). The annual incidence of hypertension in young transgender men (1.18%) seemed comparable to that of the general population. In young transgender women, it seemed higher (2.14%); we found that the choice of androgen blocker had a remarkable effect, with a highly significant increase in patients treated with cyproterone acetate (4.90%) vs. the rest (0.80%); the adjusted hazard-ratio was 0.227 (p = 0.001). Correlation, logistic regression and mediation analyses were performed for the associations of the available clinical variables with the increase in systolic blood pressure and the onset of hypertension, but besides the use of cyproterone acetate, only the ponderal gain was found significant (Spearman's r: 0.361, p < 0.001); with a 36.7% mediation effect (31.2-42.3%). Cyproterone acetate has additional known risks, such as meningioma; although we cannot conclusively prove that it has a role in the development of hypertension, we conclude that the use of cyproterone acetate for this indication should be reconsidered.


Assuntos
Hipertensão , Pessoas Transgênero , Humanos , Feminino , Masculino , Acetato de Ciproterona/efeitos adversos , Identidade de Gênero , Estudos Retrospectivos , Incidência , Androgênios , Antagonistas de Androgênios/efeitos adversos , Hipertensão/tratamento farmacológico , Hipertensão/epidemiologia
8.
Rev Cient Odontol (Lima) ; 11(4): e171, 2023.
Artigo em Espanhol | MEDLINE | ID: mdl-38312467

RESUMO

Objective: To determine the prevalence of dental anomalies of size and shape in patients aged 6 to 17 years, treated in Huánuco from 2019 to 2022. Methodology: The study was descriptive, retrospective cross-sectional with a sample of 362 Panoramic radiographs of patients 6 to 17 years of age. I make detailed observations for each observation sheet, the patient's age, sex, dental shape and size alterations, the type of dentition presented, the affected quadrant and the type of dental piece. Results: A higher prevalence of dental anomaly of shape was found with 85.10% (308) and of size with 14.9% (54). In relation to the quadrant, the tooth with rhizomycorrhexis presented the highest prevalence with 18.5% (10) in quadrant II while macrodontia presented 13.0% (7) in quadrant I and II, while the shape alteration of the shovel tooth presented the highest prevalence in quadrant II with 24.5% (76). Conclusion: There is a higher prevalence of shape anomalies as opposed to size anomalies that were less prevalent in the research work, being the female sex and the age group 11 to 17 years the most prevalent.

9.
Front Cell Dev Biol ; 10: 1073320, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36506087

RESUMO

Cutaneous wound healing is a complex process that encompasses alterations in all aspects of the skin including the extracellular matrix (ECM). ECM consist of large structural proteins such as collagens and elastin as well as smaller proteins with mainly regulative properties called matricellular proteins. Matricellular proteins bind to structural proteins and their functions include but are not limited to interaction with cell surface receptors, cytokines, or protease and evoking a cellular response. The signaling initiated by matricellular proteins modulates differentiation and proliferation of cells having an impact on the tissue regeneration. In this review we give an overview of the matricellular proteins that have been found to be involved in cutaneous wound healing and summarize the information known to date about their functions in this process.

10.
Plants (Basel) ; 11(24)2022 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-36559666

RESUMO

The Arabidopsis PROSCOOP genes belong to a family predicted to encode secreted pro-peptides, which undergo maturation steps to produce peptides named SCOOP. Some of them are involved in defence signalling through their perception by a receptor complex including MIK2, BAK1 and BKK1. Here, we focused on the PROSCOOP10 gene, which is highly and constitutively expressed in aerial organs. The MS/MS analyses of leaf apoplastic fluids allowed the identification of two distinct peptides (named SCOOP10#1 and SCOOP10#2) covering two different regions of PROSCOOP10. They both possess the canonical S-X-S family motif and have hydroxylated prolines. This identification in apoplastic fluids confirms the biological reality of SCOOP peptides for the first time. NMR and molecular dynamics studies showed that the SCOOP10 peptides, although largely unstructured in solution, tend to assume a hairpin-like fold, exposing the two serine residues previously identified as essential for the peptide activity. Furthermore, PROSCOOP10 mutations led to an early-flowering phenotype and increased expression of the floral integrators SOC1 and LEAFY, consistent with the de-regulated transcription of PROSCOOP10 in several other mutants displaying early- or late-flowering phenotypes. These results suggest a role for PROSCOOP10 in flowering time, highlighting the functional diversity within the PROSCOOP family.

11.
Biochim Biophys Acta Biomembr ; 1864(10): 184003, 2022 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-35850261

RESUMO

Cecropin D is an antimicrobial peptide from Bombyx mori displaying anticancer and pro-apoptotic activities and, together with Cecropin XJ and Cecropin A, one of the very few peptides targeting esophageal cancer. Cecropin D displays poor similarity to other cecropins but a remarkable similarity in the structure and activity spectrum with Cecropin A and Cecropin XJ, offering the possibility to highlight key motifs at the base of the biological activity. In this work we show by NMR and MD simulations that Cecropin D is partially structured in solution and stabilizes its two-helix folding upon interaction with biomimetic membranes. Simulations show that Cecropin D strongly interacts with the surface of cancer cell biomimetic bilayers where it recognises the phosphatidylserine headgroup often exposed in the outer leaflet of cancerous cells by means of specific salt bridges. Cecropin D is also able to penetrate deeply in bilayers containing cardiolipin, a phospholipid found in mitochondria, causing significant destabilization in the lipid packing which might account for its pro-apoptotic activity. In bacterial membranes, phosphatidylglycerol and phosphatidylethanolamine act synergically by electrostatically attracting cecropin D and providing access to the membrane core, respectively.


Assuntos
Bombyx , Cecropinas , Neoplasias , Animais , Apoptose , Bombyx/química , Bombyx/metabolismo , Cardiolipinas/metabolismo , Cecropinas/química , Cecropinas/metabolismo , Cecropinas/farmacologia , Mitocôndrias/metabolismo
12.
Pharmaceutics ; 14(5)2022 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-35631675

RESUMO

Despite the remarkable similarity in amino acid composition, many anticancer peptides (ACPs) display significant differences in terms of activity. This strongly suggests that particular relative dispositions of amino acids (motifs) play a role in the interaction with their biological target, which is often the cell membrane. To better verify this hypothesis, we intentionally modify HB43, an ACP active against a wide variety of cancers. Sequence alignment of related ACPs by ADAPTABLE web server highlighted the conserved motifs that could be at the origin of the activity. In this study, we show that changing the order of amino acids in such motifs results in a significant loss of activity against colon and breast cancer cell lines. On the contrary, amino acid substitution in key motifs may reinforce or weaken the activity, even when the alteration does not perturb the amphipathicity of the helix formed by HB43 on liposomes mimicking their surface. NMR and MD simulations with different membrane models (micelles, bicelles, and vesicles) indicate that the activity reflects the insertion capability in cancer-mimicking serine-exposing membranes, supported by the insertion of N-terminal phenylalanine in the FAK motif and the anchoring to the carboxylate of phosphatidylserine by means of arginine side chains.

13.
Biochimie ; 203: 51-64, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35395327

RESUMO

Sesquin is a wide spectrum antimicrobial peptide displaying a remarkable activity on fungi. Contrarily to most antimicrobial peptides, it presents an overall negative charge. In the present study, we elucidate the molecular basis of its mode of action towards biomimetic membranes by NMR and MD experiments. While a specific recognition of phosphatidylethanolamine (PE) might explain its activity in a variety of different organisms (including bacteria), a further interaction with ergosterol accounts for its strong antifungal activity. NMR data reveal a charge gradient along its amide protons allowing the peptide to reach the membrane phosphate groups despite its negative charge. Subsequently, the peptide gets structured inside the bilayer, reducing its order. MD simulations predict that its activity is retained in conditions commonly used for food preservation: low temperatures, high pressure, or the presence of electric field pulses, making Sesquin a good candidate as food preservative.


Assuntos
Antifúngicos , Bicamadas Lipídicas , Antifúngicos/farmacologia , Antifúngicos/química , Bicamadas Lipídicas/química , Conservantes de Alimentos/farmacologia , Peptídeos/farmacologia , Peptídeos/química , Fungos
14.
Exp Cell Res ; 415(1): 113111, 2022 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-35337817

RESUMO

Olfactomedin 4 (OLFM4), a multifunctional matricellular protein, is involved in regulation of angiogenesis, innate immunity, inflammation, tumorigenesis and metastasis formation via modulation of important cellular processes like adhesion, proliferation, differentiation as well as apoptosis. In our previous work we demonstrated the upregulation of OLFM4 during liver regeneration and cutaneous wound healing. Here we studied the outcomes of OLFM4 downregulation in human immortalized keratinocytes - the HaCaT cells. The suppression of OLFM4 inhibited migration but enhanced the proliferation of these cells. By using proteomic, and phosphoproteomic analysis, we found that OLFM4 downregulation induced changes in the levels of 184 proteins and 348 phosphosites. An integrated pathway analysis suggested that the increased phosphorylation of CDK7 at Ser164 and Thr170 may serve as the key event in the activation of CDK2 and consequent activation of cell cycle progression. Furthermore, the decrease in GIT1 and WAVE2 protein levels were connected to the disorganization of the actin cytoskeleton, reduction of lamellipodia formation at the leading edge of HaCaT cells, and decrease in their migration capacity.


Assuntos
Fator Estimulador de Colônias de Granulócitos , Proteômica , Citoesqueleto de Actina/metabolismo , Ciclo Celular , Divisão Celular , Proliferação de Células , Proteínas da Matriz Extracelular , Glicoproteínas , Fator Estimulador de Colônias de Granulócitos/genética , Humanos , Queratinócitos/metabolismo
15.
FEBS J ; 289(7): 1984-2003, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34767285

RESUMO

HB43 (FAKLLAKLAKKLL) is a synthetic peptide active against cell lines derived from breast, colon, melanoma, lung, prostate, and cervical cancers. Despite its remarkable spectrum of activity, the mechanism of action at the molecular level has never been investigated, preventing further optimization of its selectivity. The alternation of charged and hydrophobic residues suggests amphipathicity, but the formation of alpha-helical structure seems discouraged by its short length and the large number of positively charged residues. Using different biophysical and in silico approaches we show that HB43 is completely unstructured in solution but assumes alpha-helical conformation in the presence of DPC micelles and liposomes exposing phosphatidylserine (PS) used as mimics of cancer cell membranes. Membrane permeabilization assays demonstrate that the interaction leads to the preferential destabilization of PS-containing vesicles with respect to PC-containing ones, here used as noncancerous cell mimics. ssNMR reveals that HB43 is able to fluidify the internal structure of cancer-cell mimicking liposomes while MD simulations show its internalization in such bilayers. This is achieved by the formation of specific interactions between the lysine side chains and the carboxylate group of phosphatidylserine and/or the phosphate oxygen atoms of targeted phospholipids, which could catalyze the formation of the alpha helix required for internalization. With the aim of better understanding the peptide biocompatibility and the additional antibacterial activity, the interaction with noncancerous cell mimicking liposomes exposing phosphatidylcholine (PC) and bacterial mimicking bilayers exposing phosphatidylglycerol (PG) is also described.


Assuntos
Neoplasias , Fosfatidilserinas , Peptídeos Catiônicos Antimicrobianos/metabolismo , Membrana Celular/metabolismo , Bicamadas Lipídicas/química , Neoplasias/tratamento farmacológico , Fosfatidilgliceróis
16.
Arch Biochem Biophys ; 715: 109095, 2022 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-34826396

RESUMO

As Cecropin XJ, Cecropin A from Bombyx mori is one of the very few antimicrobial peptides having shown activity against esophageal cancer cells. It displays remarkable sequence-similarity to Cecropin XJ but slightly enhanced activity. In this work we show by NMR that both peptides are unstructured in solution but get structured in the presence of DPC micelles, mimicking the surface of biological membranes. In order to get insight into the molecular basis of its anticancer, antimicrobial and antifungal activity, we have investigated by MD simulations their interaction with a large variety of lipid bilayers mimicking cancer, mitochondrial, bacterial and fungal membranes. At variance with CecXJ, organized in two main helices, CecA tends to form a three helix bundle resulting in enhanced adaptability to its membrane targets. A specificity for the headgroup of phosphatidylserine and affinity for phosphatidylglycerol and cardiolipin may account for its selective targeting of cancer, bacterial and mitochondrial membranes, respectively.


Assuntos
Antibacterianos/metabolismo , Peptídeos Catiônicos Antimicrobianos/metabolismo , Antineoplásicos/metabolismo , Bombyx/química , Bicamadas Lipídicas/metabolismo , Sequência de Aminoácidos , Animais , Antibacterianos/química , Antifúngicos/química , Antifúngicos/metabolismo , Peptídeos Catiônicos Antimicrobianos/química , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Simulação de Dinâmica Molecular , Conformação Proteica em alfa-Hélice
17.
Front Cell Dev Biol ; 9: 745637, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34631719

RESUMO

Thrombospondin-4 (THBS4) is a non-structural extracellular matrix molecule associated with tissue regeneration and a variety of pathological processes characterized by increased cell proliferation and migration. However, the mechanisms of how THBS4 regulates cell behavior as well as the pathways contributing to its effects have remained largely unexplored. In the present study we investigated the role of THBS4 in skin regeneration both in vitro and in vivo. We found that THBS4 expression was upregulated in the dermal compartment of healing skin wounds in humans as well as in mice. Application of recombinant THBS4 protein promoted cutaneous wound healing in mice and selectively stimulated migration of primary fibroblasts as well as proliferation of keratinocytes in vitro. By using a combined proteotranscriptomic pathway analysis approach we discovered that ß-catenin acted as a hub for THBS4-dependent cell signaling and likely plays a key role in promoting its downstream effects. Our results suggest that THBS4 is an important contributor to wound healing and its incorporation into novel wound healing therapies may be a promising strategy for treatment of cutaneous wounds.

18.
PeerJ ; 9: e11373, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34040892

RESUMO

Copper (Cu) is important for plant growth, but high concentrations can lead to detrimental effects such as primary root length inhibition, vegetative tissue chlorosis, and even plant death. The interaction between plant-soil microbiota and roots can potentially affect metal mobility and availability, and, therefore, overall plant metal concentration. Cupriavidus metallidurans CH34 is a multi metal-resistant bacterial model that alters metal mobility and bioavailability through ion pumping, metal complexation, and reduction processes. The interactions between strain CH34 and plants may affect the growth, metal uptake, and translocation of Arabidopsis thaliana plants that are exposed to or not exposed to Cu. In this study, we looked also at the specific gene expression changes in C. metallidurans when co-cultured with Cu-exposed A. thaliana. We found that A. thaliana's rosette area, primary and secondary root growth, and dry weight were affected by strain CH34, and that beneficial or detrimental effects depended on Cu concentration. An increase in some plant growth parameters was observed at copper concentrations lower than 50 µM and significant detrimental effects were found at concentrations higher than 50 µM Cu. We also observed up to a 90% increase and 60% decrease in metal accumulation and mobilization in inoculated A. thaliana. In turn, copper-stressed A. thaliana altered C. metallidurans colonization, and cop genes that encoded copper resistance in strain CH34 were induced by the combination of A. thaliana and Cu. These results reveal the complexity of the plant-bacteria-metal triad and will contribute to our understanding of their applications in plant growth promotion, protection, and phytoremediation strategies.

19.
J Med Chem ; 64(8): 5185-5197, 2021 04 22.
Artigo em Inglês | MEDLINE | ID: mdl-33851832

RESUMO

Bombinins are a wide family of antimicrobial peptides from Xenopus skin. By sequence clustering, we highlighted at least three families named A, B, and H, which might exert antibacterial activity by different modes of action. In this work, we study bombinin-like peptide 3 (BLP-3) as a nonhemolytic representative of the quite unexplored class A due to its appealing activity toward WHO-priority-list bacteria such as Neisseria, Pseudomonas aeruginosa, and Staphylococcus aureus. A marked preference for cardiolipin and phosphatidylglycerol head groups, typically found in bacteria, is proven with biomimetic membranes studied by liquid and solid NMR and MD simulations. BLP-3 gets structured upon interaction and penetrates deeply into the bilayer in two steps involving a superficial insertion of key side chains and subsequent internalization. All along the pathway, a fundamental role is played by lysine residues in the conserved region 11-19, which act in synergy with other key residues.


Assuntos
Peptídeos Catiônicos Antimicrobianos/metabolismo , Materiais Biomiméticos/metabolismo , Bicamadas Lipídicas/metabolismo , Sequência de Aminoácidos , Animais , Peptídeos Catiônicos Antimicrobianos/química , Peptídeos Catiônicos Antimicrobianos/classificação , Materiais Biomiméticos/química , Bicamadas Lipídicas/química , Espectroscopia de Ressonância Magnética , Simulação de Dinâmica Molecular , Filogenia , Ligação Proteica , Conformação Proteica em alfa-Hélice , Pele/metabolismo , Xenopus/metabolismo
20.
Cancer ; 127(10): 1668-1678, 2021 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-33524166

RESUMO

BACKGROUND: Hospitalized pediatric hematology-oncology (PHO) patients have frequent clinical deterioration events (CDE) requiring intensive care unit (ICU) admission, particularly in resource-limited settings. The objective of this study was to describe CDEs in hospitalized PHO patients in Latin America and to identify event-level and center-level risk factors for mortality. METHODS: In 2017, the authors implemented a prospective registry of CDEs, defined as unplanned transfers to a higher level of care, use of ICU-level interventions on the floor, or nonpalliative floor deaths, in 16 PHO centers in 10 countries. PHO hospital admissions and hospital inpatient days were also reported. This study analyzes the first year of registry data (June 2017 to May 2018). RESULTS: Among 16 centers, 553 CDEs were reported in PHO patients during 11,536 admissions and 119,414 inpatient days (4.63 per 1000 inpatient days). Event mortality was 29% (1.33 per 1000 inpatient days) but ranged widely across centers (11%-79% or 0.36-5.80 per 1000 inpatient days). Significant risk factors for event mortality included requiring any ICU-level intervention on the floor and not being transferred to a higher level of care. Events with organ dysfunction, a higher severity of illness, and a requirement for ICU intervention had higher mortality. In center-level analysis, hospitals with a higher volume of PHO patients, less floor use of ICU intervention, lower severity of illness on transfer, and lower rates of floor cardiopulmonary arrest had lower event mortality. CONCLUSIONS: Hospitalized PHO patients who experience CDEs in resource-limited settings frequently require floor-based ICU interventions and have high mortality. Modifiable hospital practices around the escalation of care for these high-risk patients may contribute to poor outcomes. Earlier recognition of critical illness and timely ICU transfer may improve survival in hospitalized children with cancer.


Assuntos
Deterioração Clínica , Unidades de Terapia Intensiva Pediátrica , Neoplasias , Criança , Hospitalização , Humanos , Unidades de Terapia Intensiva Pediátrica/organização & administração , América Latina/epidemiologia , Neoplasias/mortalidade , Neoplasias/terapia , Estudos Prospectivos , Fatores de Risco
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