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1.
J Neurosci ; 44(39)2024 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-39134420

RESUMEN

From a glimpse of a face, people form trait impressions that operate as facial stereotypes, which are largely inaccurate yet nevertheless drive social behavior. Behavioral studies have long pointed to dimensions of trustworthiness and dominance that are thought to underlie face impressions due to their evolutionarily adaptive nature. Using human neuroimaging (N = 26, 19 female, 7 male), we identify a two-dimensional representation of faces' inferred traits in the middle temporal gyrus (MTG), a region involved in domain-general conceptual processing including the activation of social concepts. The similarity of neural-response patterns for any given pair of faces in the bilateral MTG was predicted by their proximity in trustworthiness-dominance space, an effect that could not be explained by mere visual similarity. This MTG trait-space representation occurred automatically, was relatively invariant across participants, and did not depend on the explicit endorsement of face impressions (i.e., beliefs that face impressions are valid and accurate). In contrast, regions involved in high-level social reasoning (the bilateral temporoparietal junction and posterior superior temporal sulcus; TPJ-pSTS) and entity-specific social knowledge (the left anterior temporal lobe; ATL) also exhibited this trait-space representation but only among participants who explicitly endorsed forming these impressions. Together, the findings identify a two-dimensional neural representation of face impressions and suggest that multiple implicit and explicit mechanisms give rise to biases based on facial appearance. While the MTG implicitly represents a multidimensional trait space for faces, the TPJ-pSTS and ATL are involved in the explicit application of this trait space for social evaluation and behavior.


Asunto(s)
Mapeo Encefálico , Imagen por Resonancia Magnética , Lóbulo Temporal , Humanos , Femenino , Masculino , Adulto , Adulto Joven , Lóbulo Temporal/fisiología , Lóbulo Temporal/diagnóstico por imagen , Mapeo Encefálico/métodos , Reconocimiento Facial/fisiología , Percepción Social , Estimulación Luminosa/métodos , Cara
2.
Ann Hum Genet ; 88(1): 76-85, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-37042117

RESUMEN

INTRODUCTION: Massively parallel sequencing (MPS) techniques have made a major impact on the identification of the genetic basis of inherited kidney diseases such as the ciliopathy autosomal dominant polycystic kidney disease (ADPKD). Great care must be taken when analysing MPS data in isolation from accurate phenotypic information, as this can cause misdiagnosis. METHODS: Here, we describe a family trio, recruited to the Genomics England 100,000 Genomes Project, labelled as having cystic kidney disease, who were genetically unsolved following routine data analysis pipelines. We performed a bespoke reanalysis of Whole Genome Sequencing (WGS) data and coupled this with revised phenotypic data and targeted PCR and Sanger sequencing to provide a precise molecular genetic diagnosis. RESULTS: We detected a heterozygous PKD1 frameshift variant within the WGS data which segregated with the redefined ADPKD phenotypes. An additional heterozygous exon deletion in ALG8 was also found in affected and unaffected individuals, but its precise clinical significance remains unclear. CONCLUSION: This case illustrates that reanalysis of WGS data in unsolved cases of cystic kidney disease is valuable. Clinical phenotypes must be reassessed as these may have been incorrectly recorded and evolve over time. Undertaking additional studies including genotype-phenotype correlation in wider family members provides useful diagnostic information.


Asunto(s)
Riñón Poliquístico Autosómico Dominante , Humanos , Riñón Poliquístico Autosómico Dominante/diagnóstico , Riñón Poliquístico Autosómico Dominante/genética , Canales Catiónicos TRPP/genética , Fenotipo , Riñón , Genómica , Biología Molecular , Mutación
3.
Clin Chem Lab Med ; 61(4): 674-678, 2023 03 28.
Artículo en Inglés | MEDLINE | ID: mdl-36622196

RESUMEN

Applying the concept of a value proposition to medical testing is just one of the many ways to identify and monitor the value of tests. A key part of this concept focusses on processes that should take place after a test is introduced into routine local practice, namely test implementation. This process requires identification of the clinical pathway, the stakeholders and the benefits or disbenefits that accrue to those stakeholders. There are various barriers and challenges to test implementation. Implementation requires the process of clinical audit which involves measurement of outcomes external to the laboratory but this is not widely performed in laboratory medicine. A second key challenge is that implementation requires liaison with stakeholders outside of the laboratory including clinicians and other healthcare professional such as finance managers. Many laboratories are remote from clinical care and other stakeholders making such liaison difficult. The implementation process is based on data which again will be primarily on processes outside of the laboratory. However the recent enthusiasm for so-called real world data and new data mining techniques may represent opportunities that will facilitate better test implementation. A final barrier is that a range of new tools not currently in the education curriculum of the laboratory professional is required for implementation such as those of preparing a business case to support the introduction of a test and health economic analysis. The professional bodies in laboratory medicine could assist with education in these areas.


Asunto(s)
Curriculum , Laboratorios , Humanos
4.
Artículo en Inglés | MEDLINE | ID: mdl-37589681

RESUMEN

OBJECTIVE: To study resilience and its association with HIV care engagement in a sample of young adult Black and Latinx people living with HIV (PLWH) in the United States and to test if a systems-level barrier, medical mistrust, would moderate the resilience-engagement association. METHOD: Between April and August 2021, we recruited participants through social media and dating apps (N = 212) and verified age and HIV status through a review process of digital text-messaged and emailed photos. Participants completed a one-time online survey consisting of the Connor-Davidson Resilience Scale, The Index of Engagement in HIV Care, and the Medical Mistrust Index. We ran a regression-based moderation analysis using the Johnson-Neyman Technique to estimate regions of significance. RESULTS: The sample (N = 212) was 80.5% Black and 19.5% Latinx with a mean age of 25.8 years (SD = 2.84). Higher resilience scores were associated with higher HIV care engagement scores (b = 0.72, p = .003), and medical mistrust moderated this relationship as evidenced by a mistrust by resilience interaction (b = -0.16, p = .01). Our regions of statistical significance showed that as mistrust increased, the size of the resilience-engagement association decreased. CONCLUSION: Resilience may be a protective factor associated with greater participation and sense of connection to HIV care, but is diminished by mistrust of the medical system at large. This suggest that systems-level changes, in addition to individual-level interventions, are needed to address medical mistrust to fully harness the resilience of young PLWH. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

5.
Lancet Oncol ; 23(9): 1156-1166, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35934010

RESUMEN

BACKGROUND: Few standard treatment options are available for patients with metastatic sarcomas. We did this trial to evaluate the efficacy, safety, and changes in the tumour microenvironment for durvalumab, an anti-PD-L1 drug, and tremelimumab, an anti-CTLA-4 drug, across multiple sarcoma subtypes. METHODS: In this single-centre phase 2 trial, done at The University of Texas MD Anderson Cancer Center (Houston, TX USA), patients aged 18 years or older with advanced or metastatic sarcoma with an Eastern Cooperative Oncology Group performance status of 0 or 1 who had received at least one previous line of systemic therapy were enrolled in disease subtype-specific groups (liposarcoma, leiomyosarcoma, angiosarcoma, undifferentiated pleomorphic sarcoma, synovial sarcoma, osteosarcoma, alveolar soft-part sarcoma, chordoma, and other sarcomas). Patients received 1500 mg intravenous durvalumab and 75 mg intravenous tremelimumab for four cycles, followed by durvalumab alone every 4 weeks for up to 12 months. The primary endpoint was progression-free survival at 12 weeks in the intention-to-treat population (all patients who received at least one dose of treatment). Safety was also analysed in the intention-to-treat population. This trial is registered with ClinicalTrials.gov, NCT02815995, and is completed. FINDINGS: Between Aug 17, 2016, and April 9, 2018, 62 patients were enrolled, of whom 57 (92%) received treatment and were included in the intention-to-treat population. With a median follow-up of 37·2 months (IQR 1·8-10·1), progression-free survival at 12 weeks was 49% (95% CI 36-61). 21 grade 3-4 treatment-related adverse events were reported, the most common of which were increased lipase (four [7%] of 57 patients), colitis (three [5%] patients), and pneumonitis (three [5%] patients). Nine (16%) patients had a treatment related serious adverse event. One patient had grade 5 pneumonitis and colitis. INTERPRETATION: The combination of durvalumab and tremelimumab is an active treatment regimen for advanced or metastatic sarcoma and merits evaluation in specific subsets in future trials. FUNDING: AstraZeneca.


Asunto(s)
Neoplasias Óseas , Colitis , Osteosarcoma , Neumonía , Sarcoma de Parte Blanda Alveolar , Neoplasias de los Tejidos Blandos , Anticuerpos Monoclonales , Anticuerpos Monoclonales Humanizados , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Neoplasias Óseas/tratamiento farmacológico , Humanos , Osteosarcoma/tratamiento farmacológico , Sarcoma de Parte Blanda Alveolar/tratamiento farmacológico , Neoplasias de los Tejidos Blandos/patología , Microambiente Tumoral
6.
Mov Disord ; 37(8): 1644-1653, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35723531

RESUMEN

BACKGROUND: The gut microbiome and its metabolites can impact brain health and are altered in Parkinson's disease (PD) patients. It has been recently demonstrated that PD patients have reduced fecal levels of the potent epigenetic modulator butyrate and its bacterial producers. OBJECTIVES: Here, we investigate whether the changes in the gut microbiome and associated metabolites are related to PD symptoms and epigenetic markers in leucocytes and neurons. METHODS: Stool, whole blood samples, and clinical data were collected from 55 PD patients and 55 controls. We performed DNA methylation analysis on whole blood samples and analyzed the results in relation to fecal short-chain fatty acid concentrations and microbiota composition. In another cohort, prefrontal cortex neurons were isolated from control and PD brains. We identified genome-wide DNA methylation by targeted bisulfite sequencing. RESULTS: We show that lower fecal butyrate and reduced counts of genera Roseburia, Romboutsia, and Prevotella are related to depressive symptoms in PD patients. Genes containing butyrate-associated methylation sites include PD risk genes and significantly overlap with sites epigenetically altered in PD blood leucocytes, predominantly neutrophils, and in brain neurons, relative to controls. Moreover, butyrate-associated methylated-DNA regions in PD overlap with those altered in gastrointestinal (GI), autoimmune, and psychiatric diseases. CONCLUSIONS: Decreased levels of bacterially produced butyrate are related to epigenetic changes in leucocytes and neurons from PD patients and to the severity of their depressive symptoms. PD shares common butyrate-dependent epigenetic changes with certain GI and psychiatric disorders, which could be relevant for their epidemiological relation. © 2022 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.


Asunto(s)
Microbioma Gastrointestinal , Enfermedad de Parkinson , Butiratos , Depresión/genética , Epigénesis Genética , Microbioma Gastrointestinal/genética , Humanos , Enfermedad de Parkinson/complicaciones , Enfermedad de Parkinson/genética , Enfermedad de Parkinson/microbiología
7.
Microb Ecol ; 84(1): 20-32, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34383127

RESUMEN

Different from other fungal species that can be largely cultivated in 'axenic conditions' using plant material (e.g., species of Lentinula and Pleurotus in 'sterile' straw-based substrate), the commercial Agaricus bisporus cultivation system relies heavily on ecological relationships with a broad range of microorganisms present in the system (compost and casing). Since the A. bisporus cultivation system consists of a microbial manipulation process, it is important to know the microbial community dynamics during the entire cultivation cycle to design further studies and/or crop management strategies to optimize this system. To capture the bacterial community 'flow' from compost raw materials to the casing to the formation and maturation of mushroom caps, community snapshots were generated by direct DNA recovery (amplicon sequencing). The 'bacterial community flow' revealed that compost, casing and mushrooms represent different niches for bacteria present in the cultivation system, but at the same time, a bacterial exchange between microenvironments can occur for a portion of the community. Within each microenvironment, compost showed intense bacterial populational dynamics, probably due to the environmental changes imposed by composting conditions. In casing, the colonization of A. bisporus appeared, to reshape the native bacterial community which later, with some other members present in compost, becomes the core community in mushroom caps. The current bacterial survey along with previous results provides more cues of specific bacteria groups that can be in association with A. bisporus development and health.


Asunto(s)
Agaricus , Compostaje , Microbiota , Agaricus/genética , Bacterias/genética
8.
J Gerontol Nurs ; 48(7): 31-37, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35771067

RESUMEN

Hearing loss is associated with cognitive decline in older adults. Research has shown that hearing loss negatively affects cognitive screening test measures as patients may mishear verbally administered questions. The purpose of the current study was to investigate the impact of amplification on performance on a commonly used cognitive screening test. Thirty older adults with hearing loss underwent testing with the Mini-Mental State Examination (MMSE) in three conditions: without hearing aids, with hearing aids, and with a personal listening device (PLD). Performance on the MMSE significantly improved with the use of hearing aids or a PLD. Amplification and the use of communication strategies should be considered when administering cognitive screening measures to older adults. Failure to account for hearing status may lead to invalid results and can increase the likelihood of over-referral for further assessment. [Journal of Gerontological Nursing, 48(7), 31-37.].


Asunto(s)
Disfunción Cognitiva , Audífonos , Pérdida Auditiva , Anciano , Cognición , Disfunción Cognitiva/complicaciones , Disfunción Cognitiva/diagnóstico , Pérdida Auditiva/diagnóstico , Humanos , Pruebas de Estado Mental y Demencia , Pruebas Neuropsicológicas
9.
Breast Cancer Res Treat ; 186(3): 871-882, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33575859

RESUMEN

PURPOSE: Metastatic phyllodes tumors of the breast (MPT) are rare breast neoplasms, limiting development of standardized treatment approaches. We sought to characterize the largest group of MPT thus far reported, evaluating systemic therapy outcomes. METHODS: Adult patients diagnosed with MPT between 1993 and 2015 and followed at MD Anderson Cancer Center were selected for retrospective chart review. Systemic therapy was sorted into: adriamycin/ifosfamide (AI), other anthracycline regimens, other ifosfamide regimens, gemcitabine-based regimens, and other. Given one patient may have received more than one regimen, we assumed that the effects of each regimen were independent from previous therapy. Median overall survival (OS) and progression-free survival (PFS) were estimated by the Kaplan-Meier method. Log-rank test was performed to evaluate the difference in OS between patient characteristics groups, and the differences in PFS between the five chemotherapy regimens. RESULTS: We identified 50 MPT patients, with 31 patients receiving 61 systemic regimens. Median OS was 10.7 months (95% CI: 8.67, 16.5). AI had a PFS of 9.10 months (95% CI: 5.03, 14.2), other ifosfamide regimens had a PFS of 5.10 months (95% CI: 0.67, 12.1), other anthracycline regimens had a PFS of 3.65 months (95% CI: 1.17, 7.90), gemcitabine-based regimens had a PFS of 2.80 months (95% CI: 1.83, 4.60), and other regimens had a PFS of 1.67 months (95% CI: 1.13, 7.77). CONCLUSION: MPT patients are a unique population with limited characterization to date. Our study demonstrates activity of multiple sarcoma-directed chemotherapy regimens, with ifosfamide-containing regimens having the longest PFS.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica , Neoplasias de la Mama , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Mama , Neoplasias de la Mama/tratamiento farmacológico , Supervivencia sin Enfermedad , Femenino , Humanos , Estimación de Kaplan-Meier , Estudios Retrospectivos , Resultado del Tratamiento
10.
Mol Ecol ; 30(13): 3140-3157, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-32767849

RESUMEN

Environmental DNA (eDNA) metabarcoding is emerging as a novel, objective tool for monitoring marine metazoan biodiversity. Zooplankton biodiversity in the vast open ocean is currently monitored through continuous plankton recorder (CPR) surveys, using ship-based bulk plankton sampling and morphological identification. We assessed whether eDNA metabarcoding (2 L filtered seawater) could capture similar Southern Ocean zooplankton biodiversity as conventional CPR bulk sampling (~1,500 L filtered seawater per CPR sample). We directly compared eDNA metabarcoding with (a) conventional morphological CPR sampling and (b) bulk DNA metabarcoding of CPR collected plankton (two transects for each comparison, 40 and 44 paired samples, respectively). A metazoan-targeted cytochrome c oxidase I (COI) marker was used to characterize species-level diversity. In the 2 L seawater eDNA samples, this marker amplified large amounts of non-metazoan picoplanktonic algae, but eDNA metabarcoding still detected up to 1.6 times more zooplankton species than morphologically analysed bulk CPR samples. COI metabarcoding of bulk DNA samples mostly avoided nonmetazoan amplifications and recovered more zooplankton species than eDNA metabarcoding. However, eDNA metabarcoding detected roughly two thirds of metazoan species and identified similar taxa contributing to community differentiation across the subtropical front separating transects. We observed a diurnal pattern in eDNA data for copepods which perform diel vertical migrations, indicating a surprisingly short temporal eDNA signal. Compared to COI, a eukaryote-targeted 18S ribosomal RNA marker detected a higher proportion, but lower diversity, of metazoans in eDNA. With refinement and standardization of methodology, eDNA metabarcoding could become an efficient tool for monitoring open ocean biodiversity.


Asunto(s)
ADN Ambiental , Animales , Biodiversidad , Código de Barras del ADN Taxonómico , Monitoreo del Ambiente , Océanos y Mares , Plancton/genética
11.
J Gastroenterol Hepatol ; 36(12): 3395-3401, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34370869

RESUMEN

BACKGROUND AND AIM: Our aim was to evaluate the efficacy and safety of a lumen-apposing metal stent with an electrocautery-enhanced delivery system (EDS-LAMS) for endoscopic ultrasound (EUS)-guided drainage of pancreatic fluid collections (PFCs) in regular clinical practice. METHODS: A retrospective and subsequent prospective analysis was undertaken of all patients who underwent EUS-guided drainage of their PFCs using the EDS-LAMS at 17 tertiary therapeutic endoscopy centers. RESULTS: Two hundred eight cases of EDS-LAMS deployment were attempted in 202 patients (mean age 52.9 years) at time of evaluation. Ninety-seven patients had pancreatic pseudocysts (PPs), 75 walled-off pancreatic necrosis (WOPN), 10 acute peripancreatic fluid collections (APFCs), 6 acute necrotic collections (ANCs), and 14 postoperative collections (POCs). Procedural technical success was achieved in 202/208 cases (97.1%). Maldeployment occurred in 7/208 cases (3.4%). Clinical success was achieved in 142/160 (88.8%) patients (PP 90%, WOPN 85.2%, APFC 100%, ANC 75%, POC 100%). Delayed adverse events included stent migration in 15/202 (7.4%), stent occlusion and infection in 16/202 (7.9%), major bleeding in 4/202 (2%), and buried EDS-LAMS in 2/202 (1%). PFC recurrence occurred in 13/142 (9.2%) patients; 9/202 (4.5%) required surgical or radiological intervention for PFC management after EDS-LAMS insertion. CONCLUSIONS: This large international multicenter study evaluating the EDS-LAMS for drainage of PFCs in routine clinical practice suggests that the EDS-LAMS are safe and effective for drainage of all types of PFCs; however, further endoscopic therapy is often required for WOPN. Major bleeding was a rare complication in our cohort.


Asunto(s)
Drenaje , Enfermedades Pancreáticas , Drenaje/instrumentación , Electrocoagulación , Humanos , Persona de Mediana Edad , Enfermedades Pancreáticas/cirugía , Estudios Retrospectivos , Stents
12.
Int J Obes (Lond) ; 44(10): 2124-2136, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32203115

RESUMEN

BACKGROUND: G protein-coupled receptors (GPCR) are well-characterized regulators of a plethora of physiological functions among them the modulation of adipogenesis and adipocyte function. The class of Adhesion GPCR (aGPCR) and their role in adipose tissue, however, is poorly studied. With respect to the demand for novel targets in obesity treatment, we present a comprehensive study on the expression and function of this enigmatic GPCR class during adipogenesis and in mature adipocytes. METHODS: The expression of all aGPCR representatives was determined by reanalyzing RNA-Seq data and by performing qPCR in different mouse and human adipose tissues under low- and high-fat conditions. The impact of aGPCR expression on adipocyte differentiation and lipid accumulation was studied by siRNA-mediated knockdown of all expressed members of this receptor class. The biological characteristics and function of mature adipocytes lacking selected aGPCR were analyzed by mass spectrometry and biochemical methods (lipolysis, glucose uptake, adiponectin secretion). RESULTS: More than ten aGPCR are significantly expressed in visceral and subcutaneous adipose tissues and several aGPCR are differentially regulated under high-caloric conditions in human and mouse. Receptor knockdown of six receptors resulted in an impaired adipogenesis indicating their expression is essential for proper adipogenesis. The altered lipid composition was studied in more detail for two representatives, ADGRG2/GPR64 and ADGRG6/GPR126. While GPR126 is mainly involved in adipocyte differentiation, GPR64 has an additional role in mature adipocytes by regulating metabolic processes. CONCLUSIONS: Adhesion GPCR are significantly involved in qualitative and quantitative adipocyte lipid accumulation and can control lipolysis. Factors driving adipocyte formation and function are governed by signaling pathways induced by aGPCR yielding these receptors potential targets for treating obesity.


Asunto(s)
Adipocitos/fisiología , Adipogénesis , Receptores Acoplados a Proteínas G/fisiología , Células 3T3-L1 , Animales , Humanos , Metabolismo de los Lípidos , Lipólisis , Masculino , Ratones , Ratones Endogámicos C57BL , RNA-Seq
13.
IUBMB Life ; 72(4): 601-606, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-32027092

RESUMEN

The sodium channel NaX (encoded by the SCN7A gene) was originally identified in the heart and skeletal muscle and is structurally similar to the other voltage-gated sodium channels but does not appear to be voltage gated. Although NaX is expressed at high levels in cardiac and skeletal muscle, little information exists on the function of NaX in these tissues. Transcriptional profiling of ion channels in the heart in a subset of patients with Brugada syndrome revealed an inverse relationship between the expression of NaX and NaV 1.5 suggesting that, in cardiac myocytes, the expression of these channels may be linked. We propose that NaX plays a role in excitation-contraction coupling based on our experimental observations. Here we show that in cardiac myocytes, NaX is expressed in a striated pattern on the sarcolemma in regions corresponding to the sarcomeric M-line. Knocking down NaX expression decreased NaV 1.5 mRNA and protein and reduced the inward sodium current (INa+ ) following cell depolarization. When the expression of NaV 1.5 was knocked down, ~85% of the INa+ was reduced consistent with the observations that NaV 1.5 is the main voltage-gated sodium channel in cardiac muscle and that NaX likely does not directly participate in mediating the INa+ following depolarization. Silencing NaV 1.5 expression led to significant upregulation of NaX mRNA. Similar to NaV 1.5, NaX protein levels were rapidly downregulated when the intracellular [Ca2+ ] was increased either by CaCl2 or caffeine. These data suggest that a relationship exists between NaX and NaV 1.5 and that NaX may play a role in excitation-contraction coupling.


Asunto(s)
Miocitos Cardíacos/metabolismo , Canales de Sodio Activados por Voltaje/metabolismo , Animales , Síndrome de Brugada/genética , Calcio/metabolismo , Células Cultivadas , Perros , Técnicas de Silenciamiento del Gen , Humanos , Contracción Miocárdica/fisiología , Canal de Sodio Activado por Voltaje NAV1.5/genética , Canal de Sodio Activado por Voltaje NAV1.5/metabolismo , Ratas , Sarcómeros/metabolismo , Canales de Sodio Activados por Voltaje/genética
14.
Biomacromolecules ; 21(8): 3038-3046, 2020 08 10.
Artículo en Inglés | MEDLINE | ID: mdl-32484665

RESUMEN

Rapalogues are a unique class of drugs with both cytostatic and immunosuppressive properties. Two founding members, rapamycin (Rapa) and its chemical derivative everolimus (Eve), are extremely potent, but their clinical use presents multiple challenges. Being water-insoluble, administration is restricted to the oral route, which results in a low bioavailability of <10%. Human studies of rapalogues are reported to yield a high blood to plasma ratio and poor correlation between blood concentration and dose. Moreover, treatment results in dose-limiting toxicities such as stomatitis and pneumonitis, which often leads to discontinuation of therapy. We previously reported an elastin-like polypeptide decorated with two-headed FKBP rapalogue-binding domains. Called "FAF", this biomacromolecular drug-carrier solubilizes, retargets, and releases rapalogues within disease sites. FAF-rapalogue formulations are free of cosolvents or surfactants, which promotes their parenteral administration. In this study, subcutaneously given FAF-Rapa significantly suppressed tumor growth in a mouse model of hormone receptor positive (HR+) breast cancer, compared to an oral formulation of Eve (Affinitor). Additionally, mTOR, the pharmacological target of rapalogues, was inhibited to a greater extent in tumors of FAF-Rapa and FAF-Eve groups compared to mice that received oral Eve. No signaling suppression was detected in the liver and spleen, which were evaluated to represent off-target organs exposed to the circulating formulation.


Asunto(s)
Neoplasias de la Mama , Everolimus , Animales , Neoplasias de la Mama/tratamiento farmacológico , Femenino , Humanos , Diana Mecanicista del Complejo 1 de la Rapamicina , Ratones , Péptidos , Sirolimus/farmacología
15.
Biomacromolecules ; 21(3): 1091-1102, 2020 03 09.
Artículo en Inglés | MEDLINE | ID: mdl-31927993

RESUMEN

The clinical utility of rapamycin (Rapa) is limited by solubility, bioavailability, and side effects. To overcome this, our team recently reported an elastin-like polypeptide (ELP) nanoparticle with high affinity, noncovalent drug binding, and integrin-mediated cellular uptake. Given the scarcity of pharmacology/toxicology studies of ELP-based drug carriers, this article explores safety and efficacy of ELP-Rapa. ELP-Rapa nanoparticles tested negative for hemolysis, did not interfere in plasma coagulation nor in platelet function, and did not activate the complement. Upon incubation with HepG2 cells, ELP-Rapa revealed significant cellular uptake and trafficking to acidic organelles, consistent with lysosomes. Internalized ELP-Rapa nanoparticles increased oxidative stress 4-fold compared to free drug or free ELP controls. However, mice bearing orthotopic hormone receptor positive BT-474 breast tumors, given a high dose (∼10-fold above therapeutic dose) of 1 month administration of ELP-Rapa, did not induce hepatotoxicity. On the other hand, tumor growth and mTOR signaling were suppressed without affecting body weight. Nanoparticles assembled using ELP technology appear to be a safe and efficient strategy for delivering Rapa.


Asunto(s)
Neoplasias de la Mama , Elastina , Animales , Neoplasias de la Mama/tratamiento farmacológico , Portadores de Fármacos/uso terapéutico , Elastina/uso terapéutico , Femenino , Humanos , Ratones , Péptidos/uso terapéutico , Sirolimus/farmacología
16.
Ann Allergy Asthma Immunol ; 124(5): 451-458, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32088320

RESUMEN

OBJECTIVE: To reinforce special considerations when offering and conducting oral food challenges (OFCs). DATA SOURCES: Published studies and reviews. STUDY SELECTIONS: Studies concerning OFCs and their conduct. RESULTS: Multiple OFC protocols for various clinical situations and foods were reviewed. CONCLUSION: OFCs are used for the definitive diagnosis of food allergy. Risk and benefit assessment guide the OFC procedure. The conduct of OFCs is influenced by multiple factors, including age, food, and goal of the challenge.


Asunto(s)
Hipersensibilidad a los Alimentos/diagnóstico , Inmunización/métodos , Administración Oral , Factores de Edad , Alérgenos/inmunología , Animales , Alimentos , Humanos , Guías de Práctica Clínica como Asunto , Medición de Riesgo , Factores de Riesgo , Pruebas Cutáneas
17.
Nanomedicine ; 24: 102111, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31655204

RESUMEN

Humanin (HN) is a hydrophobic 24-amino acid peptide derived from mitochondrial DNA that modulates cellular responses to oxidative stress and protects human retinal pigment epithelium (RPE) cells from apoptosis. To solubilize HN, this report describes two genetically-encoded fusions between HN and elastin-like polypeptides (ELP). ELPs provide steric stabilization and/or thermo-responsive phase separation. Fusions were designed to either remain soluble or phase separate at the physiological temperature of the retina. Interestingly, the soluble fusion assembles stable colloids with a hydrodynamic radius of 39.1 nm at 37°C. As intended, the thermo-responsive fusion forms large coacervates (>1,000 nm) at 37°C. Both fusions bind human RPE cells and protect against oxidative stress-induction of apoptosis (TUNEL, caspase-3 activation). Their activity is mediated through STAT3; furthermore, STAT3 inhibition eliminates their protection. These findings suggest that HN polypeptides may facilitate cellular delivery of biodegradable nanoparticles with potential protection against age-related diseases, including macular degeneration.


Asunto(s)
Elastina , Células Epiteliales/metabolismo , Péptidos y Proteínas de Señalización Intracelular , Nanopartículas/química , Estrés Oxidativo/efectos de los fármacos , Péptidos , Epitelio Pigmentado de la Retina/metabolismo , Apoptosis/efectos de los fármacos , Células Cultivadas , Elastina/química , Elastina/farmacología , Células Epiteliales/patología , Humanos , Péptidos y Proteínas de Señalización Intracelular/química , Péptidos y Proteínas de Señalización Intracelular/farmacología , Degeneración Macular/metabolismo , Degeneración Macular/patología , Péptidos/química , Péptidos/farmacología , Epitelio Pigmentado de la Retina/patología
18.
J Fish Dis ; 43(10): 1299-1315, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32830338

RESUMEN

Aquaculture is a rapidly growing field of food production. However, morbidity and mortality are higher in aquaculture species than in domestic animals. Bacterial diseases are a leading cause of farmed fish morbidity and are often treated with antimicrobials. Since most Swiss fish farms release effluents directly into surface water without treatment and since aquaculture fish are consumed by humans, antimicrobial resistance (AMR) and multi-resistance in aquaculture fish are important for environmental and public health. In this study, AMR tests for 14 antimicrobials were performed on 1,448 isolates from 1,134 diagnostic laboratory submissions from farmed and ornamental fish submissions for the period from 2000 to 2017. Amoxicillin, gentamycin and norfloxacin had the lowest proportion of resistant samples. However, AMR was highly variable over time. Resistance proportions were higher in: (a) ornamental fish compared with farmed fish, (b) fish from recirculation systems compared with those from other farming systems and (c) isolates originating from skin compared with those originating from inner organs. Multiple resistances were common. The results of this study provide useful data for Swiss fish veterinarians and some interesting hypotheses about risk factors for AMR in aquaculture and pet fish in Switzerland. However, further research is needed to define risk factors.


Asunto(s)
Antiinfecciosos/farmacología , Farmacorresistencia Bacteriana , Peces/microbiología , Animales , Acuicultura , Farmacorresistencia Bacteriana Múltiple , Enfermedades de los Peces/microbiología , Pruebas de Sensibilidad Microbiana , Mascotas/microbiología , Estudios Retrospectivos , Suiza
19.
J Anim Breed Genet ; 137(3): 316-330, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-31912573

RESUMEN

Non-additive genetic effects are usually ignored in animal breeding programs due to data structure (e.g., incomplete pedigree), computational limitations and over-parameterization of the models. However, non-additive genetic effects may play an important role in the expression of complex traits in livestock species, such as fertility and reproduction traits. In this study, components of genetic variance for additive and non-additive genetic effects were estimated for a variety of fertility and reproduction traits in Holstein cattle using pedigree and genomic relationship matrices. Four linear models were used: (a) an additive genetic model; (b) a model including both additive and epistatic (additive by additive) genetic effects; (c) a model including both additive and dominance effects; and (d) a full model including additive, epistatic and dominance genetic effects. Nine fertility and reproduction traits were analysed, and models were run separately for heifers (N = 5,825) and cows (N = 6,090). For some traits, a larger proportion of phenotypic variance was explained by non-additive genetic effects compared with additive effects, indicating that epistasis, dominance or a combination thereof is of great importance. Epistatic genetic effects contributed more to the total phenotypic variance than dominance genetic effects. Although these models varied considerably in the partitioning of the components of genetic variance, the models including a non-additive genetic effect did not show a clear advantage over the additive model based on the Akaike information criterion. The partitioning of variance components resulted in a re-ranking of cows based solely on the cows' additive genetic effects between models, indicating that adjusting for non-additive genetic effects could affect selection decisions made in dairy cattle breeding programs. These results suggest that non-additive genetic effects play an important role in some fertility and reproduction traits in Holstein cattle.


Asunto(s)
Epistasis Genética/genética , Fertilidad/genética , Leche , Reproducción/genética , Animales , Cruzamiento , Bovinos , Femenino , Genes Dominantes/genética , Genómica , Genotipo , Polimorfismo de Nucleótido Simple/genética , Selección Genética/genética , Estados Unidos
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