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1.
Annu Rev Biochem ; 86: 97-122, 2017 06 20.
Artículo en Inglés | MEDLINE | ID: mdl-28489421

RESUMEN

A healthy proteome is essential for cell survival. Protein misfolding is linked to a rapidly expanding list of human diseases, ranging from neurodegenerative diseases to aging and cancer. Many of these diseases are characterized by the accumulation of misfolded proteins in intra- and extracellular inclusions, such as amyloid plaques. The clear link between protein misfolding and disease highlights the need to better understand the elaborate machinery that manages proteome homeostasis, or proteostasis, in the cell. Proteostasis depends on a network of molecular chaperones and clearance pathways involved in the recognition, refolding, and/or clearance of aberrant proteins. Recent studies reveal that an integral part of the cellular management of misfolded proteins is their spatial sequestration into several defined compartments. Here, we review the properties, function, and formation of these compartments. Spatial sequestration plays a central role in protein quality control and cellular fitness and represents a critical link to the pathogenesis of protein aggregation-linked diseases.


Asunto(s)
Envejecimiento/metabolismo , Chaperonas Moleculares/metabolismo , Enfermedades Neurodegenerativas/metabolismo , Agregación Patológica de Proteínas/metabolismo , Deficiencias en la Proteostasis/metabolismo , Envejecimiento/genética , Envejecimiento/patología , Proteínas Amiloidogénicas/química , Proteínas Amiloidogénicas/genética , Proteínas Amiloidogénicas/metabolismo , Compartimento Celular , Regulación de la Expresión Génica , Humanos , Chaperonas Moleculares/genética , Enfermedades Neurodegenerativas/genética , Enfermedades Neurodegenerativas/patología , Proteínas Priónicas/química , Proteínas Priónicas/genética , Proteínas Priónicas/metabolismo , Agregación Patológica de Proteínas/genética , Agregación Patológica de Proteínas/patología , Biosíntesis de Proteínas , Conformación Proteica , Pliegue de Proteína , Replegamiento Proteico , Proteolisis , Deficiencias en la Proteostasis/genética , Deficiencias en la Proteostasis/patología
2.
Immunity ; 55(2): 324-340.e8, 2022 02 08.
Artículo en Inglés | MEDLINE | ID: mdl-35139353

RESUMEN

The aryl hydrocarbon receptor (AhR) is a sensor of products of tryptophan metabolism and a potent modulator of immunity. Here, we examined the impact of AhR in tumor-associated macrophage (TAM) function in pancreatic ductal adenocarcinoma (PDAC). TAMs exhibited high AhR activity and Ahr-deficient macrophages developed an inflammatory phenotype. Deletion of Ahr in myeloid cells or pharmacologic inhibition of AhR reduced PDAC growth, improved efficacy of immune checkpoint blockade, and increased intra-tumoral frequencies of IFNγ+CD8+ T cells. Macrophage tryptophan metabolism was not required for this effect. Rather, macrophage AhR activity was dependent on Lactobacillus metabolization of dietary tryptophan to indoles. Removal of dietary tryptophan reduced TAM AhR activity and promoted intra-tumoral accumulation of TNFα+IFNγ+CD8+ T cells; provision of dietary indoles blocked this effect. In patients with PDAC, high AHR expression associated with rapid disease progression and mortality, as well as with an immune-suppressive TAM phenotype, suggesting conservation of this regulatory axis in human disease.


Asunto(s)
Tolerancia Inmunológica/inmunología , Receptores de Hidrocarburo de Aril/inmunología , Triptófano/inmunología , Macrófagos Asociados a Tumores/inmunología , Animales , Linfocitos T CD8-positivos/inmunología , Carcinoma Ductal Pancreático/inmunología , Carcinoma Ductal Pancreático/metabolismo , Carcinoma Ductal Pancreático/mortalidad , Carcinoma Ductal Pancreático/patología , Humanos , Indoles/inmunología , Indoles/metabolismo , Linfocitos Infiltrantes de Tumor/inmunología , Ratones , Microbiota/inmunología , Neoplasias Pancreáticas/inmunología , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/mortalidad , Neoplasias Pancreáticas/patología , Pronóstico , Receptores de Hidrocarburo de Aril/antagonistas & inhibidores , Receptores de Hidrocarburo de Aril/genética , Receptores de Hidrocarburo de Aril/metabolismo , Triptófano/metabolismo , Microambiente Tumoral/efectos de los fármacos , Microambiente Tumoral/inmunología , Macrófagos Asociados a Tumores/metabolismo
3.
Mol Cell ; 83(17): 3123-3139.e8, 2023 09 07.
Artículo en Inglés | MEDLINE | ID: mdl-37625406

RESUMEN

How the essential eukaryotic chaperonin TRiC/CCT assembles from eight distinct subunits into a unique double-ring architecture remains undefined. We show TRiC assembly involves a hierarchical pathway that segregates subunits with distinct functional properties until holocomplex (HC) completion. A stable, likely early intermediate arises from small oligomers containing CCT2, CCT4, CCT5, and CCT7, contiguous subunits that constitute the negatively charged hemisphere of the TRiC chamber, which has weak affinity for unfolded actin. The remaining subunits CCT8, CCT1, CCT3, and CCT6, which comprise the positively charged chamber hemisphere that binds unfolded actin more strongly, join the ring individually. Unincorporated late-assembling subunits are highly labile in cells, which prevents their accumulation and premature substrate binding. Recapitulation of assembly in a recombinant system demonstrates that the subunits in each hemisphere readily form stable, noncanonical TRiC-like HCs with aberrant functional properties. Thus, regulation of TRiC assembly along a biochemical axis disfavors the formation of stable alternative chaperonin complexes.


Asunto(s)
Chaperonina con TCP-1 , Actinas , Chaperonina con TCP-1/química , Chaperonina con TCP-1/metabolismo , Humanos , Animales
4.
Proc Natl Acad Sci U S A ; 121(15): e2321759121, 2024 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-38579009

RESUMEN

Adjacent plant cells are connected by specialized cell wall regions, called middle lamellae, which influence critical agricultural characteristics, including fruit ripening and organ abscission. Middle lamellae are enriched in pectin polysaccharides, specifically homogalacturonan (HG). Here, we identify a plant-specific Arabidopsis DUF1068 protein, called NKS1/ELMO4, that is required for middle lamellae integrity and cell adhesion. NKS1 localizes to the Golgi apparatus and loss of NKS1 results in changes to Golgi structure and function. The nks1 mutants also display HG deficient phenotypes, including reduced seedling growth, changes to cell wall composition, and tissue integrity defects. These phenotypes are comparable to qua1 and qua2 mutants, which are defective in HG biosynthesis. Notably, genetic interactions indicate that NKS1 and the QUAs work in a common pathway. Protein interaction analyses and modeling corroborate that they work together in a stable protein complex with other pectin-related proteins. We propose that NKS1 is an integral part of a large pectin synthesis protein complex and that proper function of this complex is important to support Golgi structure and function.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Adhesión Celular/genética , Pectinas/metabolismo , Aparato de Golgi/genética , Aparato de Golgi/metabolismo , Pared Celular/metabolismo
5.
Genes Dev ; 33(15-16): 1027-1030, 2019 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-31371460

RESUMEN

Gene dosage alterations caused by aneuploidy are a common feature of most cancers yet pose severe proteotoxic challenges. Therefore, cells have evolved various dosage compensation mechanisms to limit the damage caused by the ensuing protein level imbalances. For instance, for heteromeric protein complexes, excess nonstoichiometric subunits are rapidly recognized and degraded. In this issue of Genes & Development, Brennan et al. (pp. 1031-1047) reveal that sequestration of nonstoichiometric subunits into aggregates is an alternative mechanism for dosage compensation in aneuploid budding yeast and human cell lines. Using a combination of proteomic and genetic techniques, they found that excess proteins undergo either degradation or aggregation but not both. Which route is preferred depends on the half-life of the protein in question. Given the multitude of diseases linked to either aneuploidy or protein aggregation, this study could serve as a springboard for future studies with broad-spanning implications.


Asunto(s)
Agregado de Proteínas , Proteómica , Aneuploidia , Compensación de Dosificación (Genética) , Humanos
6.
Blood ; 2024 Sep 24.
Artículo en Inglés | MEDLINE | ID: mdl-39316649

RESUMEN

There are few options for patients with relapse/refractory B-cell acute lymphoblastic leukemia (B-ALL), thus this is a major area of unmet medical need. Here, we reveal that inclusion of a poison exon in RBM39, which could be induced both by CDK9 or CDK9 independent CMGC (cyclin-dependent kinases, mitogen-activated protein kinases, glycogen synthase kinases, CDC-like kinases) kinase inhibition, is recognized by the nonsense-mediated mRNA decay (NMD) pathway for degradation. Targeting this poison exon in RBM39 with CMGC inhibitors lead to protein downregulation and inhibition of ALL growth, particularly in relapse/refractory B-ALL. Mechanistically, disruption of co-transcriptional splicing by inhibition of CMGC kinases including DYRK1A, or inhibition of CDK9, which phosphorylate the C-terminal domain of RNA polymerase II (Pol II), results in alteration of SF3B1 and Pol II association. Disruption of SF3B1 and transcriptional elongation complex alters Pol II pausing, which promotes the inclusion of a poison exon in RBM39. Moreover, RBM39 ablation suppresses the growth of human B-ALL, and targeting RBM39 with sulfonamides, which degrade RBM39 protein, showed strong anti-tumor activity in preclinical models. Our data reveal that relapse/refractory B-ALL is susceptible to pharmacologic and genetic inhibition of RBM39 and provide two potential strategies to target this axis.

7.
Blood ; 144(12): 1290-1299, 2024 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-38976877

RESUMEN

ABSTRACT: Fusion oncogenes can be cancer-defining molecular alterations that are essential for diagnosis and therapy selection.1,2 Rapid and accessible molecular diagnostics for fusion-driven leukemias such as acute promyelocytic leukemia (APL), Philadelphia chromosome-positive acute lymphoblastic leukemia, and chronic myeloid leukemia (CML) are unavailable, creating a barrier to timely diagnosis and effective targeted therapy in many health care settings, including community hospitals and low-resource environments. We developed CRISPR-based RNA-fusion transcript detection assays using SHERLOCK (specific high-sensitivity enzymatic reporter unlocking) for the diagnosis of fusion-driven leukemias. We validated these assays using diagnostic samples from patients with APL and CML from academic centers and dried blood spots from low-resource environments, demonstrating 100% sensitivity and specificity. We identified assay optimizations to enable the use of these tests outside of tertiary cancer centers and clinical laboratories, enhancing the potential impact of this technology. Rapid point-of-care diagnostics can improve outcomes for patients with cancer by expanding access to therapies for highly treatable diseases that would otherwise lead to serious adverse outcomes due to delayed or missed diagnoses.


Asunto(s)
Proteínas de Fusión Oncogénica , Humanos , Proteínas de Fusión Oncogénica/genética , Técnicas de Diagnóstico Molecular/métodos , Leucemia Promielocítica Aguda/genética , Leucemia Promielocítica Aguda/diagnóstico , Leucemia Promielocítica Aguda/terapia , Sistemas CRISPR-Cas , Leucemia Mielógena Crónica BCR-ABL Positiva/genética , Leucemia Mielógena Crónica BCR-ABL Positiva/diagnóstico , Leucemia Mielógena Crónica BCR-ABL Positiva/terapia , Leucemia/genética , Leucemia/diagnóstico , Leucemia/terapia , Repeticiones Palindrómicas Cortas Agrupadas y Regularmente Espaciadas
8.
Mol Cell Proteomics ; 22(2): 100485, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36549590

RESUMEN

The molecular chaperone heat shock protein 90 (HSP90) works in concert with co-chaperones to stabilize its client proteins, which include multiple drivers of oncogenesis and malignant progression. Pharmacologic inhibitors of HSP90 have been observed to exert a wide range of effects on the proteome, including depletion of client proteins, induction of heat shock proteins, dissociation of co-chaperones from HSP90, disruption of client protein signaling networks, and recruitment of the protein ubiquitylation and degradation machinery-suggesting widespread remodeling of cellular protein complexes. However, proteomics studies to date have focused on inhibitor-induced changes in total protein levels, often overlooking protein complex alterations. Here, we use size-exclusion chromatography in combination with mass spectrometry (SEC-MS) to characterize the early changes in native protein complexes following treatment with the HSP90 inhibitor tanespimycin (17-AAG) for 8 h in the HT29 colon adenocarcinoma cell line. After confirming the signature cellular response to HSP90 inhibition (e.g., induction of heat shock proteins, decreased total levels of client proteins), we were surprised to find only modest perturbations to the global distribution of protein elution profiles in inhibitor-treated HT29 cells at this relatively early time-point. Similarly, co-chaperones that co-eluted with HSP90 displayed no clear difference between control and treated conditions. However, two distinct analysis strategies identified multiple inhibitor-induced changes, including known and unknown components of the HSP90-dependent proteome. We validate two of these-the actin-binding protein Anillin and the mitochondrial isocitrate dehydrogenase 3 complex-as novel HSP90 inhibitor-modulated proteins. We present this dataset as a resource for the HSP90, proteostasis, and cancer communities (https://www.bioinformatics.babraham.ac.uk/shiny/HSP90/SEC-MS/), laying the groundwork for future mechanistic and therapeutic studies related to HSP90 pharmacology. Data are available via ProteomeXchange with identifier PXD033459.


Asunto(s)
Adenocarcinoma , Antineoplásicos , Neoplasias del Colon , Humanos , Proteoma/metabolismo , Adenocarcinoma/tratamiento farmacológico , Neoplasias del Colon/tratamiento farmacológico , Proteínas HSP90 de Choque Térmico , Chaperonas Moleculares , Antineoplásicos/farmacología , Espectrometría de Masas , Cromatografía en Gel
9.
Am J Gastroenterol ; 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38470031

RESUMEN

INTRODUCTION: The comparative effectiveness of upadacitinib and tofacitinib for ulcerative colitis (UC) is poorly understood. METHODS: In this retrospective cohort study, we compared steroid-free clinical remission (SFCR) and endoscopic response/remission at 52 weeks among adults initiating upadacitinib or tofacitinib for UC. RESULTS: A total of 155 patients initiated upadacitinib (n = 81; 30% prior tofacitinib exposure) or tofacitinib (n = 74; 0% prior upadacitinib exposure). After inverse probability of treatment-weighted logistic regression, upadacitinib was associated with significantly higher odds of SFCR (odds ratio 3.01, 95% confidence interval 1.39-6.55) vs tofacitinib. There were no differences for endoscopic response/remission. DISCUSSION: Upadacitinib was more effective at achieving SFCR in UC at 52 weeks vs tofacitinib.

10.
Am J Gastroenterol ; 119(2): 323-330, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-37713526

RESUMEN

INTRODUCTION: Patients with inflammatory bowel diseases (IBD) commonly require analgesic medications to treat pain, which may be associated with complications. We examined trends of analgesic use according to age at IBD onset. METHODS: This nationwide cohort study included adults diagnosed with IBD between 1996 and 2021 in Denmark. Patients were stratified according to their age at IBD onset: 18-39 years (young adult), 40-59 years (adult), and older than 60 years (older adult). We examined the proportion of patients who received prescriptions for analgesic medications within 1 year after IBD diagnosis: strong opioids, tramadol, codeine, nonsteroidal anti-inflammatory drugs, and paracetamol. Multivariable logistic regression analysis was performed to examine the association between age at IBD onset and strong opioid prescriptions and the composite of strong opioid/tramadol/codeine prescriptions. RESULTS: We identified 54,216 adults with IBD. Among them, 25,184 (46.5%) were young adults, 16,106 (29.7%) were adults, and 12,926 (23.8%) were older adults at IBD onset. Older adults most commonly received analgesic prescriptions of every class. Between 1996 and 2021, strong opioid, tramadol, and codeine prescriptions were stable, while paracetamol prescriptions increased and nonsteroidal anti-inflammatory drug prescriptions decreased. After multivariable logistic regression analysis, older adults had higher adjusted odds of receiving strong opioid prescriptions (adjusted odds ratio 1.95, 95% confidence interval 1.77-2.15) and the composite of strong opioid/tramadol/codeine prescriptions (adjusted odds ratio 1.93, 95% confidence interval 1.81-2.06) within 1 year after IBD diagnosis compared with adults. DISCUSSION: In this nationwide cohort, older adults most commonly received analgesic prescriptions within 1 year after IBD diagnosis. Additional research is needed to examine the etiology and sequelae of increased analgesic prescribing to this demographic.


Asunto(s)
Enfermedades Inflamatorias del Intestino , Tramadol , Adulto Joven , Humanos , Anciano , Adolescente , Adulto , Analgésicos Opioides/uso terapéutico , Tramadol/uso terapéutico , Estudios de Cohortes , Acetaminofén/uso terapéutico , Analgésicos/uso terapéutico , Codeína/uso terapéutico , Antiinflamatorios no Esteroideos/uso terapéutico , Enfermedades Inflamatorias del Intestino/tratamiento farmacológico , Enfermedades Inflamatorias del Intestino/epidemiología , Prescripciones de Medicamentos
11.
Am J Gastroenterol ; 119(7): 1433-1436, 2024 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-38501667

RESUMEN

ABSTRACT: Fecal microbiota transplantation (FMT) prevents recurrent Clostridioides difficile infections (rCDI) in patients with inflammatory bowel disease. Bezlotoxumab is also indicated to prevent rCDI. We assess the impact of FMT in combination with bezlotoxumab in patients with inflammatory bowel disease and rCDI. We conducted a multicenter randomized placebo-controlled trial. All received a single colonoscopic FMT. Patients were randomized 1:1 to receive bezlotoxumab or placebo. Sixty-one patients were enrolled (30 received treatment and 31 received placebo). Overall, 5 participants (8%) experienced a CDI recurrence; 4 in the treatment arm, 1 in the placebo arm (13% vs 3%, P = 0.15). There was no clear benefit to the combination approach compared with FMT alone.


Asunto(s)
Anticuerpos ampliamente neutralizantes , Infecciones por Clostridium , Trasplante de Microbiota Fecal , Enfermedades Inflamatorias del Intestino , Recurrencia , Humanos , Trasplante de Microbiota Fecal/métodos , Masculino , Femenino , Infecciones por Clostridium/terapia , Anticuerpos ampliamente neutralizantes/uso terapéutico , Adulto , Persona de Mediana Edad , Enfermedades Inflamatorias del Intestino/terapia , Enfermedades Inflamatorias del Intestino/microbiología , Resultado del Tratamiento , Terapia Combinada , Clostridioides difficile , Anticuerpos Monoclonales/uso terapéutico , Colonoscopía
12.
Nature ; 563(7731): 407-411, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-30429547

RESUMEN

Protein misfolding is linked to a wide array of human disorders, including Alzheimer's disease, Parkinson's disease and type II diabetes1,2. Protective cellular protein quality control (PQC) mechanisms have evolved to selectively recognize misfolded proteins and limit their toxic effects3-9, thus contributing to the maintenance of the proteome (proteostasis). Here we examine how molecular chaperones and the ubiquitin-proteasome system cooperate to recognize and promote the clearance of soluble misfolded proteins. Using a panel of PQC substrates with distinct characteristics and localizations, we define distinct chaperone and ubiquitination circuitries that execute quality control in the cytoplasm and nucleus. In the cytoplasm, proteasomal degradation of misfolded proteins requires tagging with mixed lysine 48 (K48)- and lysine 11 (K11)-linked ubiquitin chains. A distinct combination of E3 ubiquitin ligases and specific chaperones is required to achieve each type of linkage-specific ubiquitination. In the nucleus, however, proteasomal degradation of misfolded proteins requires only K48-linked ubiquitin chains, and is thus independent of K11-specific ligases and chaperones. The distinct ubiquitin codes for nuclear and cytoplasmic PQC appear to be linked to the function of the ubiquilin protein Dsk2, which is specifically required to clear nuclear misfolded proteins. Our work defines the principles of cytoplasmic and nuclear PQC as distinct, involving combinatorial recognition by defined sets of cooperating chaperones and E3 ligases. A better understanding of how these organelle-specific PQC requirements implement proteome integrity has implications for our understanding of diseases linked to impaired protein clearance and proteostasis dysfunction.


Asunto(s)
Núcleo Celular/metabolismo , Citoplasma/metabolismo , Proteínas Nucleares/metabolismo , Proteostasis , Saccharomyces cerevisiae/citología , Saccharomyces cerevisiae/metabolismo , Ubiquitinación , Proteínas de Ciclo Celular/deficiencia , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Enfermedad , Humanos , Modelos Biológicos , Chaperonas Moleculares/metabolismo , Complejo de la Endopetidasa Proteasomal/metabolismo , Agregación Patológica de Proteínas , Pliegue de Proteína , Saccharomyces cerevisiae/enzimología , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Ubiquitina/metabolismo , Ubiquitina-Proteína Ligasas/deficiencia , Ubiquitina-Proteína Ligasas/genética , Ubiquitina-Proteína Ligasas/metabolismo , Ubiquitinas/deficiencia , Ubiquitinas/genética , Ubiquitinas/metabolismo
13.
Ophthalmic Plast Reconstr Surg ; 40(2): 212-216, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-37972974

RESUMEN

PURPOSE: This study aims to compare the readability of patient education materials (PEM) of the American Society of Ophthalmic Plastic and Reconstructive Surgery to that of PEMs generated by the AI-chat bots ChatGPT and Google Bard. METHODS: PEMs on 16 common American Society of Ophthalmic Plastic and Reconstructive Surgery topics were generated by 2 AI models, ChatGPT 4.0 and Google Bard, with and without a 6th-grade reading level prompt modifier. The PEMs were analyzed using 7 readability metrics: Flesch Reading Ease Score, Gunning Fog Index, Flesch-Kincaid Grade Level, Coleman-Liau Index, Simple Measure of Gobbledygook Index Score, Automated Readability Index, and Linsear Write Readability Score. Each AI-generated PEM was compared with the equivalent American Society of Ophthalmic Plastic and Reconstructive Surgery PEM. RESULTS: Across all readability indices, PEM generated by ChatGPT 4.0 consistently had the highest readability scores, indicating that the material generated by this AI chatbot may be most difficult to read in its unprompted form (Flesch Reading Ease Score: 36.5; Simple Measure of Gobbledygook: 14.7). Google's Bard was able to generate content that was easier to read than both the American Society of Ophthalmic Plastic and Reconstructive Surgery and ChatGPT 4.0 (Flesch Reading Ease Score: 52.3; Simple Measure of Gobbledygook: 12.7). When prompted to produce PEM at a 6th-grade reading level, both ChatGPT 4.0 and Bard were able to significantly improve in their readability scores, with prompted ChatGPT 4.0 being able to consistently generate content that was easier to read (Flesch Reading Ease Score: 67.9, Simple Measure of Gobbledygook: 10.2). CONCLUSION: This study suggests that AI tools, when guided by appropriate prompts, can generate accessible and comprehensible PEMs in the field of ophthalmic plastic and reconstructive surgeries, balancing readability with the complexity of the necessary information.


Asunto(s)
Oftalmología , Cirugía Plástica , Humanos , Comprensión , Folletos , Educación del Paciente como Asunto
14.
J Prosthet Dent ; 2024 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-39079816

RESUMEN

A straightforward technique is presented for correcting the position of an inaccurately oriented implant analog in a digitally printed definitive cast. The technique enables the operator to reposition the analog accurately in the definitive cast and obviates the need of an additional scanning procedure or printing a new cast. The technique also permits accurate reproduction of the soft tissue contours around the implant.

15.
Environ Geochem Health ; 46(3): 79, 2024 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-38367087

RESUMEN

Significant aquifers around the world is contaminated by arsenic (As), that is regarded as a serious inorganic pollution. In this study, a biosorbent-based bio-filter column has been developed using two different plant biomasses (Colocasia esculenta stems and Artocarpus heterophyllus seeds) to remove total As from the aqueous system. Due to its natural origin, affordability, adaptability, removal effectiveness, and possibility for integration with existing systems, the biosorbent-based bio-filter column presents an alluring and promising method. It offers a practical and eco-friendly way to lessen the damaging impacts of heavy metal contamination on ecosystems and public health. In this system, As (III) is oxidized to As (V) using chlorine as an oxidant, after this post-oxidized As-contaminated water is passed through the bio-filter column to receive As-free water (or below World Health Organization permissible limit for As in drinking water). Optimization of inlet flow rate, interference of co-existing anions and cations, and life cycle of the column were studied. The maximum removal percent of As was identified to be 500 µg L-1 of initial concentration at a flow rate of 1.5 L h-1. Furthermore, the specifications of the biosorbent material was studied using elemental analysis and Zeta potential. The particle size distribution, morphological structures, and chemical composition before and after binding with As were studied using dynamic light scattering (DLS), scanning electron microscope-energy dispersive X-Ray spectroscopy (SEM-EDX), and fourier's transform infrared spectroscopy (FTIR) analysis, respectively. SuperPro 10 software was used to analyze the techno-economic viability of the complete unit and determine its ideal demand and potential. Life cycle assessment was studied to interpret the environmental impacts associated alongside the process system. Therefore, this bio-filtration system could have a potential application in rural, urban, and industrial sectors.


Asunto(s)
Arsénico , Agua Potable , Contaminantes Químicos del Agua , Purificación del Agua , Animales , Arsénico/química , Ecosistema , Estudios de Factibilidad , Espectroscopía Infrarroja por Transformada de Fourier , Estadios del Ciclo de Vida , Contaminantes Químicos del Agua/química , Adsorción , Cinética , Concentración de Iones de Hidrógeno , Purificación del Agua/métodos
16.
J Bacteriol ; 205(6): e0012623, 2023 06 27.
Artículo en Inglés | MEDLINE | ID: mdl-37249472

RESUMEN

DNA interstrand cross-links, such as those formed by psoralen-UVA irradiation, are highly toxic lesions in both humans and bacteria, with a single lesion being lethal in Escherichia coli. Despite the lack of effective repair, human cancers and bacteria can develop resistance to cross-linking treatments, although the mechanisms of resistance remain poorly defined. Here, we subjected E. coli to repeated psoralen-UVA exposure to isolate three independently derived strains that were >10,000-fold more resistant to this treatment than the parental strain. Analysis of these strains identified gain-of-function mutations in the transcriptional regulator AcrR and the alpha subunit of RNA polymerase that together could account for the resistance of these strains. Resistance conferred by the AcrR mutation is mediated at least in part through the regulation of the AcrAB-TolC efflux pump. Resistance via mutations in the alpha subunit of RNA polymerase occurs through a still-uncharacterized mechanism that has an additive effect with mutations in AcrR. Both acrR and rpoA mutations reduced cross-link formation in vivo. We discuss potential mechanisms in relation to the ability to repair and survive interstrand DNA cross-links. IMPORTANCE Psoralen DNA interstrand cross-links are highly toxic lesions with antimicrobial and anticancer properties. Despite the lack of effective mechanisms for repair, cells can become resistant to cross-linking agents through mechanisms that remain poorly defined. We derived resistant mutants and identified that two gain-of-function mutations in AcrR and the alpha subunit of RNA polymerase confer high levels of resistance to E. coli treated with psoralen-UVA. Resistance conferred by AcrR mutations occurs through regulation of the AcrAB-TolC efflux pump, has an additive effect with RNA polymerase mutations, acts by reducing the formation of cross-links in vivo, and reveals a novel mechanism by which these environmentally and clinically important agents are processed by the cell.


Asunto(s)
Proteínas de Escherichia coli , Escherichia coli , Humanos , Antibacterianos/efectos de la radiación , ADN , Escherichia coli/genética , Proteínas de Escherichia coli/genética , Ficusina/farmacología , Mutación
17.
Arch Microbiol ; 205(5): 215, 2023 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-37129684

RESUMEN

Imidacloprid, a neonicotinoid pesticide, is employed to increase crop productivity. Meanwhile, its indiscriminate application severely affects the non-target organisms and the environment. As an eco-friendly and economically workable option, the microbial intervention has garnered much attention. This review concisely outlines the toxicity, long-term environmental repercussions, degradation kinetics, biochemical pathways, and interplay of genes implicated in imidacloprid remediation. The studies have highlighted imidacloprid residue persistence in the environment for up to 3000 days. In view of high persistence, effective intervention is highly required. Bacteria-mediated degradation has been established as a viable approach with Bacillus spp. being among the most efficient at 30 â„ƒ and pH 7. Further, a comparative metagenomic investigation reveals dominant neonicotinoid degradation genes in agriculture compared to forest soils with distinctive microbial communities. Functional metabolism of carbohydrates, amino acids, fatty acids, and lipids demonstrated a significantly superior relative abundance in forest soil, implying its quality and fertility. The CPM, CYP4C71v2, CYP4C72, and CYP6AY3v2 genes that synthesize cyt p450 monooxygenase enzyme play a leading role in imidacloprid degradation. In the future, a systems biology approach incorporating integrated kinetics should be utilized to come up with innovative strategies for moderating the adverse effects of imidacloprid on the environment.


Asunto(s)
Insecticidas , Insecticidas/metabolismo , Neonicotinoides/metabolismo , Nitrocompuestos/metabolismo , Agricultura , Suelo/química
18.
J Clin Gastroenterol ; 57(7): 714-720, 2023 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-36156528

RESUMEN

GOALS: Characterize and compare the risk of Clostridioides difficile infection (CDI) and cytomegalovirus colitis (CMVC) after initiation of vedolizumab or anti-tumor necrosis factor (TNF)α agents for ulcerative colitis (UC). BACKGROUND: Immunosuppression is a risk factor for gastrointestinal infections including CDI and CMVC among patients with UC; however, the risk according to the biological class is poorly understood. STUDY: A retrospective cohort study of adults with UC involving the initiation of vedolizumab or anti-TNFα agents during June 1, 2014 to December 31, 2020 was conducted at a large academic health system. The primary outcomes for both CDI and CMVC analyses were first CDI or CMVC after biological initiation. The secondary outcome for the CDI analysis was severe CDI (>10,000 white blood cells or serum creatinine >1.5 mg/dL). Independent variables included demographics and UC history/severity factors. Inverse probability of treatment weighted Cox regression was performed to assess the hazard of CDI by biological group. Due to few outcomes, CMVC was reported descriptively. RESULTS: A total of 805 UC patients initiated vedolizumab (n=195) or anti-TNFα agents (n=610). There were 43 CDIs and 11 severe CDIs over 1436 patient-years. The inverse probability of treatment weighted Cox regression demonstrated no association between CDI and vedolizumab versus anti-TNFα (hazard ratio 0.33, 95% confidence interval 0.05-2.03), but identified a significantly lower hazard of severe CDI for vedolizumab versus anti-TNFα (hazard ratio 0.10, 95% confidence interval 0.01-0.76). There were 5 cases of CMVC, all in the anti-TNFα group. CONCLUSIONS: There was a lower adjusted risk of severe CDI but not total CDI associated with vedolizumab. CMVC was not observed after initiating vedolizumab. These findings may provide reassurance regarding the use of vedolizumab when also considering the risk of gastrointestinal infections.


Asunto(s)
Infecciones por Clostridium , Colitis Ulcerosa , Infecciones por Citomegalovirus , Adulto , Humanos , Colitis Ulcerosa/tratamiento farmacológico , Colitis Ulcerosa/patología , Factor de Necrosis Tumoral alfa , Estudios Retrospectivos , Fármacos Gastrointestinales/efectos adversos , Infecciones por Citomegalovirus/tratamiento farmacológico , Infecciones por Clostridium/tratamiento farmacológico , Resultado del Tratamiento
19.
Dig Dis Sci ; 68(1): 223-232, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-35415826

RESUMEN

BACKGROUND: The comparative long-term survival of first-line biologics for UC and reasons for drug discontinuation are poorly understood. We sought to compare the long-term drug survival related to non-response (NR) and adverse effects (AEs) for vedolizumab, adalimumab, and infliximab among biologic-naïve patients with UC. METHODS: This was a retrospective cohort study of adult biologic-naïve patients with moderate-to-severe UC initiating vedolizumab, adalimumab, or infliximab 6/1/14-12/31/20 at a large academic medical center. The primary outcome was time to biologic discontinuation for primary or secondary NR (including colectomy). The secondary outcome was time to biologic discontinuation due to AEs. Inverse probability of treatment-weighted (IPTW) Cox regression was used to perform three pair-wise comparisons of drug survival. RESULTS: The cohort included 805 patients with UC who initiated vedolizumab (n = 195), adalimumab (n = 278), or infliximab (n = 332). The adjusted hazard of biologic discontinuation for NR was significantly lower for vedolizumab vs adalimumab (HR 0.51, 95% CI 0.34-0.75), similar for vedolizumab vs infliximab (HR 1.32, 95% CI 0.79-2.18), and greater for adalimumab vs infliximab (HR 2.07, 95% CI 1.51-2.86). The adjusted hazard of discontinuation for AEs was significantly lower for vedolizumab vs adalimumab (HR 0.25, 95% CI 0.09-0.64), lower for vedolizumab vs infliximab (HR 0.21, 95% CI 0.10-0.46), and similar for adalimumab vs infliximab (HR 0.85, 95% CI 0.53-1.35). CONCLUSIONS: There was greater survival of vedolizumab compared to adalimumab for clinical response and greater survival of vedolizumab compared to both adalimumab and infliximab for AEs. These long-term data support the use of vedolizumab as a first-line biologic over adalimumab for biologic-naïve patients with UC.


Asunto(s)
Productos Biológicos , Colitis Ulcerosa , Adulto , Humanos , Adalimumab/efectos adversos , Infliximab/efectos adversos , Colitis Ulcerosa/diagnóstico , Colitis Ulcerosa/tratamiento farmacológico , Colitis Ulcerosa/inducido químicamente , Estudios Retrospectivos
20.
Surg Endosc ; 37(8): 6417-6428, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37129638

RESUMEN

BACKGROUND: The Hispanic population is the fastest growing ethnic minority in the United States, contributing to nearly half of the population growth over the last decade. Unfortunately, this population suffers from lower-than-average health literacy rates, leading to poorer health outcomes. Per the American Medical Association and National Institutes of Health, patient education materials (PEMs) should be written at no higher than a 6th grade reading level. Given that US Hispanic adults have the second-highest obesity prevalence, this study aims to analyze the readability of Spanish-language PEMs regarding bariatric surgery available in US-based academic and medical centers. METHODS: A total of 50 PEMs were found via the query ""cirugía de pérdida de peso" site: (edu OR.org)" on the Google search engine. Thirty-nine sources met the inclusion criteria of belonging to a US-based academic or medical center and containing information regarding the indications for bariatric surgery, descriptions of the types of bariatric surgery, what to expect before and after surgery, or the risks and benefits of bariatric surgery. The excerpts were analyzed according to three readability formulas designed specifically for the Spanish language and evaluated for their reading grade level. RESULTS: All 39 sources were at the college reading level per the Fry graph corrected for Spanish. Per the Spaulding formula, 37 sources were "Grade 12 + " and two sources were "Grade 8-10." Per the Fernandez-Huerta formula, 16 sources were at the 8th/9th grade reading level, 22 sources were at the 7th grade reading level, and one was at the 6th grade reading level. CONCLUSION: The Spanish-language bariatric surgery PEMs available online from US-based academic and medical centers are generally above the recommended 6th grade reading level. Failure to meet the recommended sixth-grade reading level decreases health care literacy for Spanish-speaking patients within the United States seeking bariatric surgery.


Asunto(s)
Cirugía Bariátrica , Comprensión , Adulto , Humanos , Estados Unidos , Etnicidad , Grupos Minoritarios , Educación del Paciente como Asunto , Lenguaje , Internet
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