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1.
Proteomics ; 24(5): e2300239, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37681534

RESUMEN

Despite substantial advances in the use of proteomic technologies, their widespread application in fruit tissues of non-model and recalcitrant species remains limited. This hampers the understanding of critical molecular events during the postharvest period of fleshy tropical fruits. Therefore, we evaluated label-free quantitation (LFQ) and TMT-SPS-MS3 (TMT) approaches to analyse changes in the protein profile of mango peels during postharvest period. We compared two extraction methods (phenol and chloroform/methanol) and two peptide fractionation schemes (SCX and HPRP). We accurately identified 3065 proteins, of which, 1492 were differentially accumulated over at 6 days after harvesting (DAH). Both LFQ and TMT approaches share 210 differential proteins including cell wall proteins associated with fruit softening, as well as aroma and flavour-related proteins, which were increased during postharvest period. The phenolic protein extraction and the high-pH reverse-phase peptide fractionation was the most effective pipeline for relative quantification. Nevertheless, the information provided by the other tested strategies was significantly complementary. Besides, LFQ spectra allowed us to track down intact N-glycopeptides corroborating N-glycosylations on the surface of a desiccation-related protein. This work represents the largest proteomic comparison of mango peels during postharvest period made so far, shedding light on the molecular foundation of edible fruit during ripening.


Asunto(s)
Mangifera , Mangifera/química , Mangifera/metabolismo , Proteómica , Frutas/metabolismo , Fenoles/análisis , Fenoles/metabolismo , Péptidos/análisis
2.
NMR Biomed ; 37(3): e5074, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38054254

RESUMEN

INTRODUCTION: The healthy heart has remarkable metabolic flexibility that permits rapid switching between mitochondrial glucose oxidation and fatty acid oxidation to generate ATP. Loss of metabolic flexibility has been implicated in the genesis of contractile dysfunction seen in cardiomyopathy. Metabolic flexibility has been imaged in experimental models, using hyperpolarized (HP) [2-13 C]pyruvate MRI, which enables interrogation of metabolites that reflect tricarboxylic acid (TCA) cycle flux in cardiac myocytes. This study aimed to develop methods, demonstrate feasibility for [2-13 C]pyruvate MRI in the human heart for the first time, and assess cardiac metabolic flexibility. METHODS: Good manufacturing practice [2-13 C]pyruvic acid was polarized in a 5 T polarizer for 2.5-3 h. Following dissolution, quality control parameters of HP pyruvate met all safety and sterility criteria for pharmacy release, prior to administration to study subjects. Three healthy subjects each received two HP injections and MR scans, first under fasting conditions, followed by oral glucose load. A 5 cm axial slab-selective spectroscopy approach was prescribed over the left ventricle and acquired at 3 s intervals on a 3 T clinical MRI scanner. RESULTS: The study protocol, which included HP substrate injection, MR scanning, and oral glucose load, was performed safely without adverse events. Key downstream metabolites of [2-13 C]pyruvate metabolism in cardiac myocytes include the glycolytic derivative [2-13 C]lactate, TCA-associated metabolite [5-13 C]glutamate, and [1-13 C]acetylcarnitine, catalyzed by carnitine acetyltransferase (CAT). After glucose load, 13 C-labeling of lactate, glutamate, and acetylcarnitine from 13 C-pyruvate increased by an average of 39.3%, 29.5%, and 114% respectively in the three subjects, which could result from increases in lactate dehydrogenase, pyruvate dehydrogenase, and CAT enzyme activity as well as TCA cycle flux (glucose oxidation). CONCLUSIONS: HP [2-13 C]pyruvate imaging is safe and permits noninvasive assessment of TCA cycle intermediates and the acetyl buffer, acetylcarnitine, which is not possible using HP [1-13 C]pyruvate. Cardiac metabolite measurement in the fasting/fed states provides information on cardiac metabolic flexibility and the acetylcarnitine pool.


Asunto(s)
Miocardio , Ácido Pirúvico , Humanos , Ácido Pirúvico/metabolismo , Miocardio/metabolismo , Glucosa/metabolismo , Acetilcarnitina/metabolismo , Miocitos Cardíacos , Ácido Glutámico/metabolismo , Lactatos/metabolismo , Isótopos de Carbono/metabolismo
3.
Biotechnol Bioeng ; 121(4): 1284-1297, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38240126

RESUMEN

Product association of host-cell proteins (HCPs) to monoclonal antibodies (mAbs) is widely regarded as a mechanism that can enable HCP persistence through multiple purification steps and even into the final drug substance. Discussion of this mechanism often implies that the existence or extent of persistence is directly related to the strength of binding but actual measurements of the binding affinity of such interactions remain sparse. Two separate avenues of investigation of HCP-mAb binding are reported here. One is the measurement of the affinity of binding of individual, commonly persistent Chinese hamster ovary (CHO) HCPs to each of a set of mAbs, and the other uses quantitative proteomic measurements to assess binding of HCPs in a null CHO harvested cell culture fluid (HCCF) to mAbs produced in the same cell line. The individual HCP measurements show that the binding affinities of individual HCPs to different mAbs can vary appreciably but are rarely very high, with only weak pH dependence. The measurements on the null HCCF allow estimation of individual HCP-mAb affinities; these are typically weaker than those seen in affinity measurements on isolated HCPs. Instead, the extent of binding appears correlated with the initial abundance of individual HCPs in the HCCF and the forms of the HCPs in the solution, i.e., whether HCPs are present as free molecules or as parts of large aggregates. Separate protein A chromatography experiments performed by feeding different fractions of a mAb-containing HCCF obtained by size-exclusion chromatography (SEC) showed clear differences in the number and identity of HCPs found in the protein A eluate. These results indicate a significant role for HCP-mAb association in determining HCP persistence through protein A chromatography, presumably through binding of HCP-mAb complexes to the resin. Overall, the results illustrate the importance of considering more fully the biophysical context of HCP-product association in assessing the factors that may affect the phenomenon and determine its implications. Knowledge of the abundances and the forms of individual or aggregated HCPs in HCCF are particularly significant, emphasizing the integration of upstream and downstream bioprocessing and the importance of understanding the collective properties of HCPs in addition to just the biophysical properties of individual HCPs.


Asunto(s)
Anticuerpos Monoclonales , Proteómica , Cricetinae , Animales , Cricetulus , Proteómica/métodos , Células CHO , Anticuerpos Monoclonales/química , Cromatografía en Gel , Proteína Estafilocócica A/química
4.
Biotechnol Bioeng ; 121(1): 291-305, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-37877536

RESUMEN

Host-cell proteins (HCPs) are the foremost class of process-related impurities to be controlled and removed in downstream processing steps in monoclonal antibody (mAb) manufacturing. However, some HCPs may evade clearance in multiple purification steps and reach the final drug product, potentially threatening drug stability and patient safety. This study extends prior work on HCP characterization and persistence in mAb process streams by using mass spectrometry (MS)-based methods to track HCPs through downstream processing steps for seven mAbs that were generated by five different cell lines. The results show considerable variability in HCP identities in the processing steps but extensive commonality in the identities and quantities of the most abundant HCPs in the harvests for different processes. Analysis of HCP abundance in the harvests shows a likely relationship between abundance and the reproducibility of quantification measurements and suggests that some groups of HCPs may hinder the characterization. Quantitative monitoring of HCPs persisting through purification steps coupled with the findings from the harvest analysis suggest that multiple factors, including HCP abundance and mAb-HCP interactions, can contribute to the persistence of individual HCPs and the identification of groups of common, persistent HCPs in mAb manufacturing.


Asunto(s)
Anticuerpos Monoclonales , Cricetinae , Animales , Humanos , Anticuerpos Monoclonales/química , Reproducibilidad de los Resultados , Cricetulus , Espectrometría de Masas , Células CHO
5.
Biomacromolecules ; 25(1): 338-348, 2024 01 08.
Artículo en Inglés | MEDLINE | ID: mdl-38117685

RESUMEN

Proteins are exposed to hydrostatic pressure (HP) in a variety of ecosystems as well as in processing steps such as freeze-thaw, cell disruption, sterilization, and homogenization, yet pressure effects on protein-protein interactions (PPIs) remain underexplored. With the goal of contributing toward the expanded use of HP as a fundamental control parameter in protein research, processing, and engineering, small-angle X-ray scattering was used to examine the effects of HP and ionic strength on ovalbumin, a model protein. Based on an extensive data set, we develop an empirical method for scaling PPIs to a master curve by combining HP and osmotic effects. We define an effective pressure parameter that has been shown to successfully apply to other model protein data available in the literature, with deviations evident for proteins that do not follow the apparent Hofmeister series. The limitations of the empirical scaling are discussed in the context of the hypothesized underlying mechanisms.


Asunto(s)
Ecosistema , Proteínas , Concentración Osmolar , Ovalbúmina , Fenómenos Biofísicos
6.
J Am Acad Dermatol ; 90(5): 911-926, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-37516356

RESUMEN

Drug-induced hypersensitivity syndrome, also known as drug reaction with eosinophilia and systemic symptoms, is a severe cutaneous adverse reaction characterized by an exanthem, fever, and hematologic and visceral organ involvement. The differential diagnosis includes other cutaneous adverse reactions, infections, inflammatory and autoimmune diseases, and neoplastic disorders. Three sets of diagnostic criteria have been proposed; however, consensus is lacking. The cornerstone of management is immediate discontinuation of the suspected drug culprit. Systemic corticosteroids remain first-line therapy, but the literature on steroid-sparing agents is expanding. Longitudinal evaluation for sequelae is recommended. Adjunctive tests for risk stratification and drug culprit identification remain under investigation. Part II of this continuing medical education activity begins by exploring the differential diagnosis and diagnosis of drug-induced hypersensitivity syndrome/drug reaction with eosinophilia and systemic symptoms and concludes with an evidence-based overview of evaluation and treatment.


Asunto(s)
Síndrome de Hipersensibilidad a Medicamentos , Eosinofilia , Humanos , Síndrome de Hipersensibilidad a Medicamentos/diagnóstico , Síndrome de Hipersensibilidad a Medicamentos/etiología , Síndrome de Hipersensibilidad a Medicamentos/terapia , Eosinofilia/inducido químicamente , Eosinofilia/diagnóstico , Eosinofilia/terapia , Piel , Corticoesteroides/uso terapéutico , Fiebre
7.
J Am Acad Dermatol ; 90(5): 885-908, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-37516359

RESUMEN

Drug-induced hypersensitivity syndrome (DiHS), also known as drug reaction with eosinophilia and systemic symptoms (DRESS), is a severe cutaneous adverse reaction (SCAR) characterized by an exanthem, fever, and hematologic and visceral organ involvement. Anticonvulsants, antibiotics, and allopurinol are the most common triggers. The pathogenesis involves a complex interplay between drugs, viruses, and the immune system primarily mediated by T-cells. DiHS/DRESS typically presents with a morbilliform eruption 2-6 weeks after drug exposure, and is associated with significant morbidity, mortality, and risk of relapse. Long-term sequelae primarily relate to organ dysfunction and autoimmune diseases. Part I of this continuing medical education activity on DiHS/DRESS provides an update on epidemiology, novel insights into pathogenesis, and a description of clinicopathological features and prognosis.


Asunto(s)
Síndrome de Hipersensibilidad a Medicamentos , Eosinofilia , Humanos , Síndrome de Hipersensibilidad a Medicamentos/diagnóstico , Síndrome de Hipersensibilidad a Medicamentos/epidemiología , Síndrome de Hipersensibilidad a Medicamentos/etiología , Eosinofilia/epidemiología , Eosinofilia/inducido químicamente , Anticonvulsivantes/efectos adversos , Piel , Pronóstico
8.
Am J Dermatopathol ; 46(10): 679-684, 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-39141745

RESUMEN

ABSTRACT: This article reports two cases of the 2022 mpox virus with notable histopathology, and includes a novel description of mpox pseudotumor in the perianal region which is not previously described. This article additionally includes literature review of characteristic histopathology through evolving lesions, as it is sparsely described in relation to the 2022 mpox outbreak. Case one describes a 42-year-old man who presented with umbilicated, smooth papules on the trunk and extremities, and milia-like papules on the face. Histopathology of an umbilicated lesion revealed epidermal acanthosis with keratinocyte pallor, ballooning degeneration, keratinocyte necrosis, and neutrophilic epitheliotropism. Case two describes a 51-year-old man who presented with scattered eroded papules as well as a perianal mass. Histopathology of the mass revealed ulceration with keratinocyte enlargement and pallor with a mixed inflammatory cell infiltrate. It additionally revealed rare multinucleated keratinocytes with nuclear molding. These cases are remarkable and contribute to literature as reports of the histopathology of the atypical 2022 mpox outbreak are rare. A combination of clinical, laboratory, and histopathologic evidence is useful in diagnosing mpox, and these cases contribute to describing the evolution of viral lesions.


Asunto(s)
Mpox , Adulto , Humanos , Masculino , Persona de Mediana Edad , Queratinocitos/patología , Queratinocitos/virología , Mpox/diagnóstico , Mpox/patología , Mpox/virología
9.
Am J Dermatopathol ; 46(10): 663-667, 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-38842316

RESUMEN

BACKGROUND: Cellulitis is a significant public health burden and lacks a gold standard for diagnosis. Up to 1/3 of patients are incorrectly diagnosed. The skin biopsy has been proposed as the gold standard. OBJECTIVE: In this study, we evaluate the histopathologic characteristics and tissue culture positivity of biopsies in patients diagnosed with cellulitis seen by our inpatient dermatology consultation service. METHODS: This retrospective cohort study examined patients who were hospitalized with a skin and soft tissue infection at our institution between 2011 and 2020 and underwent a skin biopsy. RESULTS: Those with a positive tissue culture were more likely to die within 30 days compared with those with negative tissue cultures (26% vs. 6%, P = 0.048). Patients who died within 30 days were more likely to have acute interstitial inflammation as a feature on histopathology (38%, P = 0.03). LIMITATIONS: Single institutional design, unintentional exclusion of patients with organism-specific diagnosis, and selection for a medically complex patient population because of the nonroutine collection of biopsies. CONCLUSION: Positive tissue cultures and histopathology showing acute interstitial space inflammation on skin and soft tissue infection (SSTI) biopsies are associated with increased mortality and thus may serve as indicators of poor prognosis.


Asunto(s)
Celulitis (Flemón) , Piel , Humanos , Celulitis (Flemón)/patología , Celulitis (Flemón)/diagnóstico , Celulitis (Flemón)/mortalidad , Estudios Retrospectivos , Masculino , Femenino , Persona de Mediana Edad , Biopsia , Anciano , Pronóstico , Piel/patología , Adulto , Enfermedad Aguda , Infecciones de los Tejidos Blandos/patología , Infecciones de los Tejidos Blandos/mortalidad , Infecciones de los Tejidos Blandos/diagnóstico , Técnicas de Cultivo de Tejidos , Anciano de 80 o más Años
10.
J Dairy Sci ; 2024 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-39122154

RESUMEN

Bioactive peptides produced via enzymatic hydrolysis have been widely investigated for their dipeptidyl peptidase-IV (DPP-IV) inhibitory properties. However, deficit of studies on fermentation as a mean to produce DPP-IV inhibitory peptides prompted us to draw a comparative study on DPP-IV inhibitory peptides generated from cow, camel, goat, and sheep milk using probiotic fermentation. Further, peptide identification, in silico molecular interactions with DPP-IV, and ensemble docking were performed. Results obtained suggested that goat milk consistently exhibited higher hydrolysis than other milk types. Further, Pediococcus pentosaceus (PP-957) emerged as a potent probiotic, with significantly lower DPP-IV-IC50 values 0.17, 0.12, and 0.25 µg/mL protein equivalent in fermented cow, camel, and goat milk, respectively. Overall, peptides (RPPPPVAM, CHNLDELKDTR, and VLSLSQPK) exhibited strong binding affinity with binding energies of -9.31, -9.18 and -8.9 Kcal·mol-1, respectively, suggesting their potential role as DPP-IV inhibitors. Overall, this study, offers valuable information toward antidiabetic benefits of fermented milk products via inhibition of DPP-IV.

11.
JAMA ; 332(1): 31-40, 2024 07 02.
Artículo en Inglés | MEDLINE | ID: mdl-38744430

RESUMEN

Importance: Effective weight loss interventions are needed for men with obesity. Objective: To determine whether an intervention that combined text messaging with financial incentives attained significant weight loss at the 12-month follow-up compared with the control group and whether an intervention of text messaging alone attained significant weight loss at the 12-month follow-up compared with the control group. Design, Setting, and Participants: An assessor-blinded randomized clinical trial conducted in Belfast, Bristol, and Glasgow areas in the UK. A total of 585 men with body mass index (BMI) of 30 or more were enrolled between July 2021 and May 2022. Final follow-up occurred June 2023. Interventions: Participants were randomly assigned to 12 months of behavioral focused text messages combined with financial incentives (n = 196), 12 months of behavioral focused text messages alone (n= 194), or a waiting list (control group; n= 195). The financial incentive consisted of a monetary reward that was lost if weight loss targets were not met. All participants received weight management information and a pedometer at baseline. Main Outcomes and Measures: The 2 primary comparisons were the 12-month comparison of within-participant weight change between the text messaging with financial incentive group and the control group and the comparison between the text messaging alone group and the control group (minimum clinically important difference, 3%). The P value defined for statistical significance was P < .025 for each comparison. Results: Of the 585 men (mean [SD] age, 50.7 [13.3] years; mean weight, 118.5 [19.9] kg; mean BMI, 37.7 [5.7]; 525 [90%] White), 227 (39%) lived in postal code areas with lower socioeconomic status, and 426 (73%) completed the 12-month follow-up. At the 12-month follow-up, compared with the control group, the mean percent weight change was significantly greater in the text messaging with financial incentive group (mean difference, -3.2%; 97.5% CI, -4.6% to -1.9%; P < .001) but was not significantly greater in the text messaging alone group (mean difference, -1.4%; 97.5% CI, -2.9% to 0.0, P = .05). The mean (SD) weight changes were -5.7 (7.4) kg for the text messaging with financial incentives group, -3.0 (7.5) kg for the text messaging alone group, and -1.5 (6.6) kg for the control group. The 12-month mean (SD) percentage weight changes from baseline were -4.8% (6.1%) for the text messaging with financial incentives group, -2.7% (6.3%) for text messaging alone group, and -1.3% (5.5%) for the control group. Of 366 adverse events reported, the most common were infections (83 [23%]). Of the 23 serious adverse events (6.3%), 12 (52%) occurred in the text messaging with financial incentives group, 5 (22%) in the texts messaging alone group, and 6 (26%) in the control group. None were considered related to participating in a trial group. Conclusion and Relevance: Among men with obesity, an intervention with text messaging with financial incentive significantly improved weight loss compared with a control group, whereas text messaging alone was not significantly better than the control condition. These findings support text messaging combined with financial incentives to attain weight loss in men with obesity. Trial Registration: isrctn.org Identifier: ISRCTN91974895.


Asunto(s)
Motivación , Obesidad , Envío de Mensajes de Texto , Programas de Reducción de Peso , Adulto , Humanos , Masculino , Persona de Mediana Edad , Índice de Masa Corporal , Obesidad/terapia , Recompensa , Método Simple Ciego , Pérdida de Peso , Programas de Reducción de Peso/métodos , Programas de Reducción de Peso/economía , Reino Unido , Población Blanca
12.
Exp Physiol ; 2023 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-37120805

RESUMEN

NEW FINDINGS: What is the topic of this review? The vagus nerve is a crucial regulator of cardiovascular homeostasis, and its activity is linked to heart health. Vagal activity originates from two brainstem nuclei: the nucleus ambiguus (fast lane) and the dorsal motor nucleus of the vagus (slow lane), nicknamed for the time scales that they require to transmit signals. What advances does it highlight? Computational models are powerful tools for organizing multi-scale, multimodal data on the fast and slow lanes in a physiologically meaningful way. A strategy is laid out for how these models can guide experiments aimed at harnessing the cardiovascular health benefits of differential activation of the fast and slow lanes. ABSTRACT: The vagus nerve is a key mediator of brain-heart signaling, and its activity is necessary for cardiovascular health. Vagal outflow stems from the nucleus ambiguus, responsible primarily for fast, beat-to-beat regulation of heart rate and rhythm, and the dorsal motor nucleus of the vagus, responsible primarily for slow regulation of ventricular contractility. Due to the high-dimensional and multimodal nature of the anatomical, molecular and physiological data on neural regulation of cardiac function, data-derived mechanistic insights have proven elusive. Elucidating insights has been complicated further by the broad distribution of the data across heart, brain and peripheral nervous system circuits. Here we lay out an integrative framework based on computational modelling for combining these disparate and multi-scale data on the two vagal control lanes of the cardiovascular system. Newly available molecular-scale data, particularly single-cell transcriptomic analyses, have augmented our understanding of the heterogeneous neuronal states underlying vagally mediated fast and slow regulation of cardiac physiology. Cellular-scale computational models built from these data sets represent building blocks that can be combined using anatomical and neural circuit connectivity, neuronal electrophysiology, and organ/organismal-scale physiology data to create multi-system, multi-scale models that enable in silico exploration of the fast versus slow lane vagal stimulation. The insights from the computational modelling and analyses will guide new experimental questions on the mechanisms regulating the fast and slow lanes of the cardiac vagus toward exploiting targeted vagal neuromodulatory activity to promote cardiovascular health.

13.
Biotechnol Bioeng ; 120(4): 1068-1080, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36585356

RESUMEN

In the production of biopharmaceuticals such as monoclonal antibodies (mAbs) and vaccines, the residual amounts of host-cell proteins (HCPs) are among the critical quality attributes. In addition to overall HCP levels, individual HCPs may elude purification, potentially causing issues in product stability or patient safety. Such HCP persistence has been attributed mainly to biophysical interactions between individual HCPs and the product, resin media, or residual chromatin particles. Based on measurements on process streams from seven mAb processes, we have found that HCPs in aggregates, not necessarily chromatin-derived, may play a significant role in the persistence of many HCPs. Such aggregates may also hinder accurate detection of HCPs using existing proteomics methods. The findings also highlight that certain HCPs may be difficult to remove because of their functional complementarity to the product; specifically, chaperones and other proteins involved in the unfolded protein response (UPR) are disproportionately present in the aggregates. The methods and findings described here expand our understanding of the origins and potential behavior of HCPs in cell-based biopharmaceutical processes and may be instrumental in improving existing techniques for HCP detection and clearance.


Asunto(s)
Productos Biológicos , Agregado de Proteínas , Cricetinae , Animales , Humanos , Cricetulus , Anticuerpos Monoclonales , Proteómica/métodos , Células CHO
14.
J Cardiovasc Magn Reson ; 25(1): 77, 2023 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-38093285

RESUMEN

BACKGROUND: The heart has metabolic flexibility, which is influenced by fed/fasting states, and pathologies such as myocardial ischemia and hypertrophic cardiomyopathy (HCM). Hyperpolarized (HP) 13C-pyruvate MRI is a promising new tool for non-invasive quantification of myocardial glycolytic and Krebs cycle flux. However, human studies of HP 13C-MRI have yet to demonstrate regional quantification of metabolism, which is important in regional ischemia and HCM patients with asymmetric septal/apical hypertrophy. METHODS: We developed and applied methods for whole-heart imaging of 13C-pyruvate, 13C-lactate and 13C-bicarbonate, following intravenous administration of [1-13C]-pyruvate. The image acquisition used an autonomous scanning method including bolus tracking, real-time magnetic field calibrations and metabolite-specific imaging. For quantification of metabolism, we evaluated 13C metabolite images, ratio metrics, and pharmacokinetic modeling to provide measurements of myocardial lactate dehydrogenase (LDH) and pyruvate dehydrogenase (PDH) mediated metabolic conversion in 5 healthy volunteers (fasting & 30 min following oral glucose load). RESULTS: We demonstrate whole heart coverage for dynamic measurement of pyruvate-to-lactate conversion via LDH and pyruvate-to-bicarbonate conversion via PDH at a resolution of 6 × 6 × 21 mm3 (13C-pyruvate) and 12 × 12 × 21 mm3 (13C-lactate, 13C-bicarbonate). 13C-pyruvate and 13C-lactate were detected simultaneously in the RV blood pool, immediately after intravenous injection, reflecting LDH activity in blood. In healthy volunteers, myocardial 13C-pyruvate-SNR, 13C-lactate-SNR, 13C-bicarbonate-SNR, 13C-lactate/pyruvate ratio, 13C-pyruvate-to-lactate conversion rate, kPL, and 13C-pyruvate-to-bicarbonate conversion rate, kPB, all had statistically significant increases following oral glucose challenge. kPB, reflecting PDH activity and pyruvate entering the Krebs Cycle, had the highest correlation with blood glucose levels and was statistically significant. CONCLUSIONS: We demonstrate first-in-human regional quantifications of cardiac metabolism by HP 13C-pyruvate MRI that aims to reflect LDH and PDH activity.


Asunto(s)
Bicarbonatos , Ácido Pirúvico , Humanos , Valor Predictivo de las Pruebas , Imagen por Resonancia Magnética/métodos , Glucosa , Ácido Láctico/metabolismo , Isótopos de Carbono
15.
Proc Natl Acad Sci U S A ; 117(13): 7004-7010, 2020 03 31.
Artículo en Inglés | MEDLINE | ID: mdl-32179691

RESUMEN

Protein mobility at solid-liquid interfaces can affect the performance of applications such as bioseparations and biosensors by facilitating reorganization of adsorbed protein, accelerating molecular recognition, and informing the fundamentals of adsorption. In the case of ion-exchange chromatographic beads with small, tortuous pores, where the existence of surface diffusion is often not recognized, slow mass transfer can result in lower resin capacity utilization. We demonstrate that accounting for and exploiting protein surface diffusion can alleviate the mass-transfer limitations on multiple significant length scales. Although the surface diffusivity has previously been shown to correlate with ionic strength (IS) and binding affinity, we show that the dependence is solely on the binding affinity, irrespective of pH, IS, and resin ligand density. Different surface diffusivities give rise to different protein distributions within the resin, as characterized using confocal microscopy and small-angle neutron scattering (length scales of micrometer and nanometer, respectively). The binding dependence of surface diffusion inspired a protein-loading approach in which the binding affinity, and hence the surface diffusivity, is modulated by varying IS. Such gradient loading increased the protein uptake efficiency by up to 43%, corroborating the importance of protein surface diffusion in protein transport in ion-exchange chromatography.


Asunto(s)
Resinas de Intercambio Iónico/química , Modelos Químicos , Proteínas/química , Difusión
16.
Opt Lett ; 47(22): 5913-5916, 2022 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-37219135

RESUMEN

We investigate the emission characteristics of a tri-atomic photonic meta-molecule with asymmetric intra-modal couplings which is uniformly excited by an incident waveform tuned to coherent virtual absorption conditions. By analyzing the dynamics of the discharged radiation, we identify a parameter domain where its directional re-emission properties are optimal.

17.
Biotechnol Bioeng ; 119(7): 1873-1889, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35377460

RESUMEN

The growth of advanced analytics in manufacturing monoclonal antibodies (mAbs) has highlighted the challenges associated with the clearance of host cell proteins (HCPs). Of special concern is the removal of "persistent" HCPs, including immunogenic and mAb-degrading proteins, that co-elute from the Protein A resin and can escape the polishing steps. Responding to this challenge, we introduced an ensemble of peptide ligands that target the HCPs in Chinese hamster ovary (CHO) cell culture fluids and enable mAb purification via flow-through affinity chromatography. This study describes their integration into LigaGuard™, an affinity adsorbent featuring an equilibrium binding capacity of ~30 mg of HCPs per mL of resin as well as dynamic capacities up to 16 and 22 mg/ml at 1- and 2-min residence times, respectively. When evaluated against cell culture harvests with different mAb and HCP titers and properties, LigaGuard™ afforded high HCP clearance, with logarithmic removal values (LRVs) up to 1.5, and mAb yield above 90%. Proteomic analysis of the effluents confirmed the removal of high-risk HCPs, including cathepsins, histones, glutathione-S transferase, and lipoprotein lipases. Finally, combining LigaGuard™ for HCP removal with affinity adsorbents for product capture afforded a global mAb yield of 85%, and HCP and DNA LRVs > 4.


Asunto(s)
Anticuerpos Monoclonales , Proteómica , Animales , Anticuerpos Monoclonales/química , Células CHO , Técnicas de Cultivo de Célula , Cromatografía de Afinidad/métodos , Cricetinae , Cricetulus , Péptidos/química , Proteómica/métodos
18.
J Am Acad Dermatol ; 87(3): 597-604, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-34293386

RESUMEN

Chimeric antigen receptor T-cell therapy is an emerging immunotherapy with promising efficacy for the treatment of previously refractory or relapsed malignancies. As a personalized medicine approach, T cells are genetically engineered to express a receptor designed to bind a specific tumor antigen, leading to selective immune-mediated destruction of tumor cells. Due to the novelty of chimeric antigen receptor T-cell therapy, the safety profile continues to evolve with limited information currently available on cutaneous adverse events. Improved understanding of the spectrum of cutaneous adverse events may facilitate earlier recognition and appropriate management of these toxicities. To explore this knowledge gap, we discuss the available case reports and clinical trial results of cutaneous reactions associated with chimeric antigen receptor T-cell therapy.


Asunto(s)
Receptores Quiméricos de Antígenos , Enfermedades de la Piel , Tratamiento Basado en Trasplante de Células y Tejidos , Dermatólogos , Humanos , Recurrencia Local de Neoplasia , Receptores de Antígenos de Linfocitos T/genética , Receptores de Antígenos de Linfocitos T/uso terapéutico , Receptores Quiméricos de Antígenos/genética , Receptores Quiméricos de Antígenos/uso terapéutico
19.
Support Care Cancer ; 30(7): 5591-5600, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35107598

RESUMEN

BACKGROUND: Cutaneous adverse events (AEs) following cancer immunotherapy, targeted therapy, and chemotherapy have been well-documented in the literature. A number of case reports have identified phototherapy, a form of light therapy that mimics sunlight exposure, as a noninvasive treatment modality for these cutaneous toxicities. By inducing local suppression of the immune system, phototherapy is a skin-directed treatment with minimal effect on tumor response. Phototherapy may therefore be a viable treatment option for cutaneous AEs from cancer therapies. METHODS: We reviewed the literature for patients treated with phototherapy for cutaneous AEs following cancer immunotherapy, targeted therapy, or chemotherapy. We also included three previously unpublished cases from our own institution. RESULTS: We identified 24 patients (80% male, mean age 67 years, range 49-75 years). Patients received the following phototherapy types: NB-UVB (n = 17), PUVA (n = 6), or PDT (n = 1). A topical steroid was used in conjunction with phototherapy in seven patients. At phototherapy onset, cancer treatment was either continued, temporarily discontinued, or discontinued (n = 9, 6, 7, respectively; in two cases, the cancer treatment course was unknown). Improvement of cutaneous AEs was observed in 96% of patients. CONCLUSIONS: Phototherapy resulted in full or partial improvement in all but one patient. A topical steroid was used in nearly a third of patients, suggesting some oncodermatologists co-administer topicals to further boost response. Continuation of cancer therapy in the majority of patients highlights an additional advantage of phototherapy. We believe phototherapy may be an effective adjunctive treatment to topical steroids when treating these cutaneous toxicities.


Asunto(s)
Terapia Ultravioleta , Administración Cutánea , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Fototerapia/efectos adversos , Fototerapia/métodos , Piel , Resultado del Tratamiento , Terapia Ultravioleta/efectos adversos , Terapia Ultravioleta/métodos
20.
J Thromb Thrombolysis ; 54(2): 323-329, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35543796

RESUMEN

Therapeutic advances have resulted in increased life expectancy in patients with hemophilia. Consequently, the prevalence of coronary artery disease in this population is increasing. Little is known about the optimal management of acute coronary syndrome in these patients. Current guidelines for the management of this condition are based mainly on expert opinion and generally recommend administration of the clotting factor prior to the anticoagulant, antiplatelet, and interventional therapies. We report a case that illustrates the potential harm that may come from this approach: evolution of non-ST-segment elevation acute coronary syndrome into ST-elevation acute coronary syndrome during the administration of recombinant clotting factor. We review available literature and describe the refined informatics-based guidelines for managing acute coronary syndrome in patients with hemophilia we developed in response to the presented clinical case. We propose adopting this novel informatics-based approach, which aids in the identification and early treatment of these patients, operationalizes timely involvement of hematology experts, and gathers data for further study.


Asunto(s)
Síndrome Coronario Agudo , Enfermedad de la Arteria Coronaria , Hemofilia A , Síndrome Coronario Agudo/tratamiento farmacológico , Anticoagulantes/uso terapéutico , Hemofilia A/complicaciones , Hemofilia A/tratamiento farmacológico , Humanos
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