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1.
Nucleic Acids Res ; 51(D1): D603-D610, 2023 01 06.
Artículo en Inglés | MEDLINE | ID: mdl-36399496

RESUMEN

With an ever-increasing amount of (meta)genomic data being deposited in sequence databases, (meta)genome mining for natural product biosynthetic pathways occupies a critical role in the discovery of novel pharmaceutical drugs, crop protection agents and biomaterials. The genes that encode these pathways are often organised into biosynthetic gene clusters (BGCs). In 2015, we defined the Minimum Information about a Biosynthetic Gene cluster (MIBiG): a standardised data format that describes the minimally required information to uniquely characterise a BGC. We simultaneously constructed an accompanying online database of BGCs, which has since been widely used by the community as a reference dataset for BGCs and was expanded to 2021 entries in 2019 (MIBiG 2.0). Here, we describe MIBiG 3.0, a database update comprising large-scale validation and re-annotation of existing entries and 661 new entries. Particular attention was paid to the annotation of compound structures and biological activities, as well as protein domain selectivities. Together, these new features keep the database up-to-date, and will provide new opportunities for the scientific community to use its freely available data, e.g. for the training of new machine learning models to predict sequence-structure-function relationships for diverse natural products. MIBiG 3.0 is accessible online at https://mibig.secondarymetabolites.org/.


Asunto(s)
Genoma , Genómica , Familia de Multigenes , Vías Biosintéticas/genética
2.
Phytother Res ; 30(4): 557-66, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26744260

RESUMEN

Breast cancer is a major health problem affecting the female population worldwide. The triple-negative breast cancers (TNBCs) are characterized by malignant phenotypes, worse patient outcomes, poorest prognosis, and highest mortality rates. The proto-oncogenic receptor tyrosine kinase c-Met is usually dysregulated in TNBCs, contributing to their oncogenesis, tumor progression, and aggressive cellular invasiveness that is strongly linked to tumor metastasis. Therefore, c-Met is proposed as a promising candidate target for the control of TNBCs. Lichens-derived metabolites are characterized by their structural diversity, complexity, and novelty. The chemical space of lichen-derived metabolites has been extensively investigated, albeit their biological space is still not fully explored. The anticancer-guided fractionation of Usnea strigosa (Ach.) lichen extract led to the identification of the depsidone-derived norstictic acid as a novel bioactive hit against breast cancer cell lines. Norstictic acid significantly suppressed the TNBC MDA-MB-231 cell proliferation, migration, and invasion, with minimal toxicity to non-tumorigenic MCF-10A mammary epithelial cells. Molecular modeling, Z'-LYTE biochemical kinase assay and Western blot analysis identified c-Met as a potential macromolecular target. Norstictic acid treatment significantly suppressed MDA-MB-231/GFP tumor growth of a breast cancer xenograft model in athymic nude mice. Lichen-derived natural products are promising resources to discover novel c-Met inhibitors useful to control TNBCs.


Asunto(s)
Lactonas/farmacología , Proteínas Proto-Oncogénicas c-met/antagonistas & inhibidores , Salicilatos/farmacología , Neoplasias de la Mama Triple Negativas/patología , Usnea/química , Animales , Línea Celular Tumoral/efectos de los fármacos , Movimiento Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Células Epiteliales/efectos de los fármacos , Femenino , Humanos , Ratones , Ratones Desnudos , Simulación del Acoplamiento Molecular , Invasividad Neoplásica , Proteínas Proto-Oncogénicas c-met/metabolismo , Neoplasias de la Mama Triple Negativas/metabolismo , Ensayos Antitumor por Modelo de Xenoinjerto
3.
Artículo en Inglés | MEDLINE | ID: mdl-38010094

RESUMEN

BACKGROUND: Vitamin D deficiency is a common finding in critically ill children. However, the optimal supplementation strategy in this patient population is unknown. The objective of this study was to evaluate the effects of high-dose (10 000 IU/kg, max. 400 000 IU) vitamin D supplementation on 25-hydroxyvitamin D3 (25[OH]D3) levels in pediatric intensive care unit (PICU) patients with baseline vitamin D deficiency. METHODS: This was a prospective, institutional review board-approved pilot research study performed at the University of South Alabama Women's and Children's Hospital in Mobile, AL. The study sample consisted of patients less than 18 years old admitted to the PICU with baseline 25-hydroxyvitamin D (25[OH]D) level less than 30 ng/ml. Included patients received a one-time dose of vitamin D3 orally or via gastric tube (10 000 IU/kg, max. 400 000 IU). RESULTS: A total of 17 patients were screened with 11 included in the study. Blood analysis revealed a significant increase in 25(OH)D3 level from baseline to 12-h post dose (21.6 [4.5] ng/ml vs. 46.7 [15.5] ng/ml, P < 0.001). At the 12-h post-dose time point, 10/11 patients (91%) had 25(OH)D3 levels that were greater than 30 ng/ml. No adverse effects were observed. CONCLUSION: Vitamin D3 supplementation at a dose of 10 000 IU/kg (max. 400 000 IU) significantly increased 25(OH)D3 levels in critically ill pediatric patients.

4.
Clin Transl Sci ; 16(6): 1002-1011, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36861661

RESUMEN

Kratom is a widely used Asian botanical that has gained popularity in the United States due to a perception that it can treat pain, anxiety, and opioid withdrawal symptoms. The American Kratom Association estimates 10-16 million people use kratom. Kratom-associated adverse drug reactions (ADRs) continue to be reported and raise concerns about the safety profile of kratom. However, studies are lacking that describe the overall pattern of kratom-associated adverse events and quantify the association between kratom and adverse events. ADRs reported to the US Food and Drug Administration Adverse Event Reporting System from January 2004 through September 2021 were used to address these knowledge gaps. Descriptive analysis was conducted to analyze kratom-related adverse reactions. Conservative pharmacovigilance signals based on observed-to-expected ratios with shrinkage were estimated by comparing kratom to all other natural products and drugs. Based on 489 deduplicated kratom-related ADR reports, users were young (mean age 35.5 years), and more often male (67.5%) than female patients (23.5%). Cases were predominantly reported since 2018 (94.2%). Fifty-two disproportionate reporting signals in 17 system-organ-class categories were generated. The observed/reported number of kratom-related accidental death reports was 63-fold greater than expected. There were eight strong signals related to addiction or drug withdrawal. An excess proportion of ADR reports were about kratom-related drug complaints, toxicity to various agents, and seizures. Although further research is needed to assess the safety of kratom, clinicians and consumers should be aware that real-world evidence points to potential safety threats.


Asunto(s)
Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos , Mitragyna , Estados Unidos/epidemiología , Humanos , Masculino , Femenino , Adulto , Mitragyna/efectos adversos , United States Food and Drug Administration , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos/epidemiología , Analgésicos Opioides , Dolor
5.
ArXiv ; 2023 Nov 13.
Artículo en Inglés | MEDLINE | ID: mdl-38013887

RESUMEN

Proteomics is the large scale study of protein structure and function from biological systems through protein identification and quantification. "Shotgun proteomics" or "bottom-up proteomics" is the prevailing strategy, in which proteins are hydrolyzed into peptides that are analyzed by mass spectrometry. Proteomics studies can be applied to diverse studies ranging from simple protein identification to studies of proteoforms, protein-protein interactions, protein structural alterations, absolute and relative protein quantification, post-translational modifications, and protein stability. To enable this range of different experiments, there are diverse strategies for proteome analysis. The nuances of how proteomic workflows differ may be challenging to understand for new practitioners. Here, we provide a comprehensive overview of different proteomics methods to aid the novice and experienced researcher. We cover from biochemistry basics and protein extraction to biological interpretation and orthogonal validation. We expect this work to serve as a basic resource for new practitioners in the field of shotgun or bottom-up proteomics.

6.
JAMA Netw Open ; 6(7): e2326366, 2023 07 03.
Artículo en Inglés | MEDLINE | ID: mdl-37523190

RESUMEN

Importance: Practice guidelines often provide recommendations in which the strength of the recommendation is dissociated from the quality of the evidence. Objective: To create a clinical guideline for the diagnosis and management of adult bacterial infective endocarditis (IE) that addresses the gap between the evidence and recommendation strength. Evidence Review: This consensus statement and systematic review applied an approach previously established by the WikiGuidelines Group to construct collaborative clinical guidelines. In April 2022 a call to new and existing members was released electronically (social media and email) for the next WikiGuidelines topic, and subsequently, topics and questions related to the diagnosis and management of adult bacterial IE were crowdsourced and prioritized by vote. For each topic, PubMed literature searches were conducted including all years and languages. Evidence was reported according to the WikiGuidelines charter: clear recommendations were established only when reproducible, prospective, controlled studies provided hypothesis-confirming evidence. In the absence of such data, clinical reviews were crafted discussing the risks and benefits of different approaches. Findings: A total of 51 members from 10 countries reviewed 587 articles and submitted information relevant to 4 sections: establishing the diagnosis of IE (9 questions); multidisciplinary IE teams (1 question); prophylaxis (2 questions); and treatment (5 questions). Of 17 unique questions, a clear recommendation could only be provided for 1 question: 3 randomized clinical trials have established that oral transitional therapy is at least as effective as intravenous (IV)-only therapy for the treatment of IE. Clinical reviews were generated for the remaining questions. Conclusions and Relevance: In this consensus statement that applied the WikiGuideline method for clinical guideline development, oral transitional therapy was at least as effective as IV-only therapy for the treatment of IE. Several randomized clinical trials are underway to inform other areas of practice, and further research is needed.


Asunto(s)
Endocarditis Bacteriana , Endocarditis , Guías de Práctica Clínica como Asunto , Adulto , Humanos , Consenso , Endocarditis/diagnóstico , Endocarditis/terapia , Endocarditis Bacteriana/prevención & control , Estudios Prospectivos
7.
Fungal Biol ; 126(11-12): 697-706, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36517138

RESUMEN

Lichenized fungi are known for their production of a diversity of secondary metabolites, many of which have broad biological and pharmacological applications. By far the most well-studied of these metabolites is usnic acid. While this metabolite has been well-known and researched for decades, the gene cluster responsible for its production was only recently identified from the species Cladonia uncialis. Usnic acid production varies considerably in the genus Cladonia, even among closely related taxa, and many species, such as C. rangiferina, have been inferred to be incapable of producing the metabolite based on analysis by thin-layer chromatography (TLC). We sequenced and examined the usnic acid biosynthetic gene clusters, or lack thereof, from four closely related Cladonia species (C. oricola, C. rangiferina, C. stygia, and C. subtenuis), and compare them against those of C. uncialis. We complement this comparison with tiered chemical profile analyses to confirm the presence or absence of usnic acid in select samples, using both HPLC and LC-MS. Despite long-standing reporting that C. rangiferina lacks the ability to produce usnic acid, we observed functional gene clusters from the species and detected usnic acid when extracts were examined by LC-MS. By contrast, C. stygia and C. oricola, have been previously described as lacking the ability to produce usnic acid, lacked the gene cluster entirely, and no usnic acid could be detected in C. oricola extracts via HPLC or LC-MS. This work suggests that chemical profiles attained through inexpensive and low-sensitivity methods like TLC may fail to detect low abundance metabolites that can be taxonomically informative. This study also bolsters understanding of the usnic acid gene cluster in lichens, revealing differences among domains of the polyketide synthase which may explain observed differences in expression. These results reinforce the need for comprehensive characterization of lichen secondary metabolite profiles with sensitive LC-MS methods.


Asunto(s)
Ascomicetos , Benzofuranos , Líquenes , Cromatografía Liquida , Líquenes/microbiología , Familia de Multigenes , Sintasas Poliquetidas/genética , Sintasas Poliquetidas/metabolismo , Ascomicetos/genética , Ascomicetos/metabolismo , Benzofuranos/metabolismo
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