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1.
Exp Mol Pathol ; 139: 104921, 2024 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-39096892

RESUMEN

Seizures are neurological disorders triggered by an imbalance in the activity of excitatory and inhibitory neurotransmitters in the brain. When triggered chronically, this imbalance can lead to epilepsy. Critically, many of the affected individuals are refractory to treatment. Given this, anti-inflammatory drugs, in particular glucocorticoids, have been considered as a potential antiepileptogenic therapy. Glucocorticoids are currently used in the treatment of refractory patients, although there have been contradictory results in terms of their use in association with antiepileptic drugs, which reinforces the need for a more thorough investigation of their effects. In this context, the present study evaluated the effects of dexamethasone (DEX, 0.6 mg/kg) on the electroencephalographic (EEG) and histopathological parameters of male Wistar rats submitted to acute seizure induced by pentylenetetrazol (PTZ). The EEG monitoring revealed that DEX reduced the total brainwave power, in comparison with PTZ, in 12 h after the convulsive episode, exerting this effect in up to 36 h (p < 0.05 for all comparisons). An increase in the accommodation of the oscillations of the delta, alpha, and gamma frequencies was also observed from the first 12 h onwards, with the accommodation of the theta frequency occurring after 36 h, and that of the beta frequency 24 h after the seizure. The histopathological analyses showed that the CA3 region and hilum of the hippocampus suffered cell loss after the PTZ-induced seizure (control vs. PTZ, p < 0.05), although DEX was not able to protect these regions against cell death (PTZ vs. DEX + PTZ, p > 0.05). While DEX did not reverse the cell damage caused by PTZ, the data indicate that DEX has beneficial properties in the EEG analysis, which makes it a promising candidate for the attenuation of the epileptiform wave patterns that can precipitate refractory seizures.

2.
Nutrients ; 16(15)2024 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-39125278

RESUMEN

(1) Background: We examined the effect of the acute administration of olive oil (EVOO), linseed oil (GLO), soybean oil (SO), and palm oil (PO) on gastric motility and appetite in rats. (2) Methods: We assessed food intake, gastric retention (GR), and gene expression in all groups. (3) Results: Both EVOO and GLO were found to enhance the rate of stomach retention, leading to a decrease in hunger. On the other hand, the reduction in food intake caused by SO was accompanied by delayed effects on stomach retention. PO caused an alteration in the mRNA expression of NPY, POMC, and CART. Although PO increased stomach retention after 180 min, it did not affect food intake. It was subsequently verified that the absence of an autonomic reaction did not nullify the influence of EVOO in reducing food consumption. Moreover, in the absence of parasympathetic responses, animals that received PO exhibited a significant decrease in food consumption, probably mediated by lower NPY expression. (4) Conclusions: This study discovered that different oils induce various effects on parameters related to food consumption. Specifically, EVOO reduces food consumption primarily through its impact on the gastrointestinal tract, making it a recommended adjunct for weight loss. Conversely, the intake of PO limits food consumption in the absence of an autonomic reaction, but it is not advised due to its contribution to the development of cardiometabolic disorders.


Asunto(s)
Regulación del Apetito , Hipotálamo , Neuropéptido Y , Aceite de Oliva , Aceite de Palma , Aceite de Soja , Nervio Vago , Animales , Nervio Vago/efectos de los fármacos , Nervio Vago/fisiología , Hipotálamo/metabolismo , Hipotálamo/efectos de los fármacos , Masculino , Aceite de Oliva/farmacología , Neuropéptido Y/genética , Neuropéptido Y/metabolismo , Aceite de Palma/farmacología , Regulación del Apetito/efectos de los fármacos , Aceite de Soja/administración & dosificación , Aceite de Soja/farmacología , Ratas Wistar , Aceite de Linaza/farmacología , Ratas , Ingestión de Alimentos/efectos de los fármacos , Aceites de Plantas/farmacología , Proopiomelanocortina/genética , Proopiomelanocortina/metabolismo , Proteínas del Tejido Nervioso/genética , Proteínas del Tejido Nervioso/metabolismo , Motilidad Gastrointestinal/efectos de los fármacos , Regulación de la Expresión Génica/efectos de los fármacos , ARN Mensajero/metabolismo , ARN Mensajero/genética
3.
J Phys Chem A ; 2024 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-39158513

RESUMEN

This work presents a detailed investigation aimed at understanding the key mechanisms governing nitric oxide (NO) production in N2-O2 discharges by systematically comparing experimental results to modeling data. The experimental phase capitalizes on radiofrequency (13.56 MHz) discharges, sustained at 5 mbar pressure conditions, featuring varying concentrations of oxygen, ranging from pure N2 plasma to air-like mixtures. On the modeling front, we adopt an integrated approach that combines the solution of the Boltzmann equation for electrons with a system of rate balance equations for heavy species. To account for ground state NO(X) generation at the reactor wall, we combine the volume chemistry with a mesoscopic description of the surface, taking into account adsorption sites and various elementary surface phenomena. Comparisons between experiments and modeling demonstrate very good agreement, extending beyond NO(X) formation to encompass other species in the plasma such as N2O(X) and atomic nitrogen N(4S). Noteworthy findings include (i) the pivotal role of surface mechanisms in NO(X) production, particularly at low oxygen content values; (ii) the significance of accurately describing the postdischarge phase, where depletion of plasma species occurs at different time scales (millisecond range); and (iii) the importance of vibrationally and electronically excited states (e.g., O2(b)) in elucidating NO(X) formation dynamics, crucial for unraveling reaction pathways and energy transfer processes. This work makes an important step toward formulating a comprehensive reaction mechanism for N2 and N2-O2 plasmas applied to nitrogen fixation, covering both volume and surface mechanisms, and lays a robust foundation for future research on plasma-based NO(X) production, particularly in the presence of catalysts.

4.
Vet Parasitol Reg Stud Reports ; 53: 101066, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39025540

RESUMEN

Cuniculus paca, commonly known as the paca, is a rodent of the Cuniculidae family that is widely distributed throughout the Americas, including all Brazilian territories, and is abundant in the Amazon region. It is one of the most hunted species and faces significant predation in the extreme western Amazon region of Brazil because it constitutes a staple in the diet of local communities, for subsistence and commercial purposes. Understanding the helminthic fauna of these animals is of paramount importance, given that some nematodes have zoonotic potential and may pose risks to consumer health. This study aimed to contribute to the records of the nemtodes of this highly consumed species in the Amazon region, highlighting the occurrence of gastrointestinal parasites in free-living pacas intended for human subsistence consumption. The study was conducted in the Paranã da Floresta community, located in the municipality of Guajará, Amazonas from 2022 to 2023. The community members hunted this rodent for consumption and voluntarily provided the viscera for analysis. Nematodes were extracted from each organ. The organs were opened, and the contents were processed using a sieve (0.15 mm) and subsequently evaluated separately. In total, 10,157 nematodes were found in the 14 pacas. Based on morphological analyses, the nematodes were identified as Heligmostrongylus sedecimradiatus (n = 10,068), Trichuris sp. (n = 85), and Physaloptera sp. (n = 4). This study provides insights into the nematodes diversity of free-living pacas in the extreme Western Amazon region, emphasizing the importance of sanitary surveillance and public awareness of the risks associated with bushmeat consumption.


Asunto(s)
Nematodos , Infecciones por Nematodos , Animales , Brasil/epidemiología , Nematodos/aislamiento & purificación , Nematodos/clasificación , Infecciones por Nematodos/veterinaria , Infecciones por Nematodos/parasitología , Infecciones por Nematodos/epidemiología , Cuniculidae/parasitología , Masculino , Femenino , Enfermedades de los Roedores/parasitología , Enfermedades de los Roedores/epidemiología , Humanos
5.
Emerg Nurse ; 2024 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-38978385

RESUMEN

This article examines the role of water in the body, the balance of fluids in the body and the provision of intravenous (IV) fluids to patients who are dehydrated, providing a comprehensive overview of these topics for nurses. The author details various aspects of practice in IV fluid therapy, including the types of fluids used, their indications, administration and potential side effects. The article also discusses dehydration and how nurses can identify and treat this complication, which can occur as a result of many different conditions. Drawing on the relevant research, this article aims to advance nurses' knowledge of the care of patients who are dehydrated and require IV fluid therapy.

6.
Mater Horiz ; 2024 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-38962871

RESUMEN

Ammonia synthesis via the catalytic Haber-Bosch process is characterized by its high pressures and low single-pass conversions, as well as by the energy-intensive production of the precursors H2 and N2 and their concomitant greenhouse gas emissions. Alternatively, thermochemical cycles based on metal nitrides stand as a promising pathway to green ammonia production because they can be conducted at moderate pressures without added catalysts and be further driven by concentrated solar energy as the source of high-temperature process heat. The ideal two-step cycle consists of the nitridation of a metal to form a metal nitride, followed by the hydrogenation of the metal nitride to synthetize NH3 and reform the metal. Here, we perform a combined theoretical and experimental screening of mono-metallic nitrides for several candidates, namely for Sr, Ca, Cr, Mn, Fe, Co, Ni, Cu, Zn, Mo, W, Li, and Al. For the theoretical screening, Ellingham diagrams and chemical equilibrium compositions are examined with thermodynamic data derived from density function theory computations. For the experimental screening, thermogravimetric runs and mass balances supported by on-line gas analyses are performed for both steps of the cycle at ambient pressure and over the temperature ranges 100-1000 °C for nitridation and 100-500 °C for hydrogenation. The strontium-based cycle is selected as a reference for detailed examination and shown to synthetize NH3 at 1 bar by effecting the nitridation at 407 °C (at peak rate) and the hydrogenation at 339 °C (at peak rate). The co-formation of metal hydrides (SrH2) and metal imides (Sr2HN) are shown to help close the material cycle.

7.
Anal Sci ; 2024 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-38907795

RESUMEN

Organotin compounds (OTC), mainly tributyltin (TBT), have been used since the 1970s as biocides in the composition of antifouling paints. Due to its physical-chemical characteristics, TBT has high toxicity to the marine environment affecting non-target organisms. The present study aims to develop a method of direct visual identification of TBT in antifouling paints using the cyclopalladate complex, 4- (2-thiazolylazo) resorcinol (TAR-Pd), synthesized in our laboratory. Tests were performed in blank and in the paint matrix with the following OTC: TBT-O; TBT-Cl; TPT-Cl; DBT-Cl (tributyltin oxide, tributyltin chloride, triphenyltin chloride, dibutyltin chloride), in addition to the SnCl4 and SnCl2 compounds (tin IV chloride and tin II chloride), all at a concentration of approximately 20 g/ kg of dry paint). The test was performed by applying paint samples to test bodies and scraping a few tens of milligrams of the dry paint film. The scraped paint samples were submitted to the test, showing a different staining reaction for the TBT-Cl and SnCl4 samples concerning blank and other samples (TBT-O, TPT, DBT-Cl, and SnCl2). Solution tests were performed to characterize reaction products by spectroscopy in the visible band. The method developed has potential for application in real samples, being selective for TBT-Cl and SnCl4 in an acid medium, obtaining a limit of detection, in the range of 1-10 mg/kg dry paint.

8.
Future Cardiol ; : 1-6, 2024 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-38899747

RESUMEN

The CardioMEMS™ system remotely monitors changes in pulmonary artery pressures, which allows for early detection of heart failure worsening. It is a safe and reliable invasive monitoring system. We report a case in which there was a late migration of the device at 6 months of follow-up to the contralateral pulmonary artery. The mechanisms, consequences, and management of device migration are discussed. To our knowledge, there are very few published data on late sensor migration.


The CardioMEMS™ system keeps track of changes in lung artery pressure from a distance. This helps spot early signs of heart failure getting worse. It is a safe and dependable way to keep an eye on things inside the body. We describe a situation where the sensor moved to the opposite lung artery 6 months later. We talk about why this happens, what it means, and how to handle it. There is not much info out there about sensors moving late, as far as we know.

9.
Materials (Basel) ; 17(10)2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38793445

RESUMEN

A significant and increasing number of studies have been dedicated to complex concentrated alloys (CCAs) due to the improved properties that these metallic materials can exhibit. However, while most of these studies employ melting techniques, only a few explore powder metallurgy and pressureless sintering as production methods. In this work, a microstructural characterization of AlCrCuFeMnNi CCA samples obtained by powder metallurgy and pressureless sintering using mixtures of powders with different compositions was carried out. One batch of samples (B1) was prepared using commercial powders of Al, Cr, Cu, Fe, Mn, and Ni. Another batch (B2) used mixtures of CrFeMn, AlNi, and Cu powders. A third set of samples (B3) was obtained by adding 1% at. of Mg to the B2 powder. The samples were characterized by X-ray diffraction, scanning and transmission electron microscopy, energy dispersive spectroscopy, density measurements, and hardness tests. Thermodynamic calculations were also used to complement the microstructural characterization. All the obtained samples exhibited high relative density and hardness values. However, B3 samples showed a higher hardness, attributed to the finer distribution of oxide particles, which was promoted by the presence of Mg during sintering. These last samples presented a hardness/density ratio of 62 HV/(g cm-3), surpassing that of some martensitic stainless steels and nickel-titanium alloys.

10.
ACS Pharmacol Transl Sci ; 7(5): 1637-1649, 2024 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-38751615

RESUMEN

Nitrocatechols are the standard pharmacophore to develop potent tight-binding inhibitors of catechol O-methyltransferase (COMT), which can be used as coadjuvant drugs to manage Parkinson's disease. Tolcapone is the most potent drug of this class, but it has raised safety concerns due to its potential to induce liver damage. Tolcapone-induced hepatotoxicity has been attributed to the nitrocatechol moiety; however, other nitrocatechol-based COMT inhibitors, such as entacapone, are safe and do not damage the liver. There is a knowledge gap concerning which mechanisms and chemical properties govern the toxicity of nitrocatechol-based COMT inhibitors. Using a vast array of cell-based assays, we found that tolcapone-induced toxicity is caused by direct interference with mitochondria that does not depend on bioactivation by P450. Our findings also suggest that (a) lipophilicity is a key property in the toxic potential of nitrocatechols; (b) the presence of a carbonyl group directly attached to the nitrocatechol ring seems to increase the reactivity of the molecule, and (c) the presence of cyano moiety in double bond stabilizes the reactivity decreasing the cytotoxicity. Altogether, the fine balance between lipophilicity and the chemical nature of the C1 substituents of the nitrocatechol ring may explain the difference in the toxicological behavior observed between tolcapone and entacapone.

11.
Healthcare (Basel) ; 12(9)2024 Apr 27.
Artículo en Inglés | MEDLINE | ID: mdl-38727471

RESUMEN

Hospital accreditation has become ubiquitous in developing countries. While research acknowledges that accreditation can enhance healthcare quality, efficiency, and safety, concerns persist regarding hospitals' management of conflicts stemming from the diverse institutional logic inherent in this process. Therefore, this study aimed to investigate how professional and market logic, alongside conflicts arising from institutional demands, affect compliance with hospital accreditation. To this end, we conducted a multiple-case study in four Brazilian hospitals employing in-depth interviews and on-site observations. The triangulation of narrative analysis and the outcomes of multiple correspondence analysis revealed that when professional logic predominates, there is a greater propensity to tailor accredited activities by segmenting the tasks between physicians and nurses with the intention of mitigating existing conflicts. Conversely, when conflicts occur over established goals between professionals and orientated marked logic executives, the accreditation process is impeded, resulting in non-compliance. Ultimately, the findings underscore the alignment between the pursuit of legitimacy and efficiency within the accreditation process. We conclude by delineating the theoretical and practical implications of scrutinizing the internal dynamics of institutional logic.

12.
Clin Infect Dis ; 79(1): 215-222, 2024 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-38568992

RESUMEN

BACKGROUND: In high-resource settings, the survival of children with immunocompromise (IC) has increased and immunosuppressive therapies are increasingly being used. This study aimed to determine the clinical characteristics, performance of diagnostic tools, and outcome of IC children with tuberculosis (TB) in Europe. METHODS: Multicenter, matched case-control study within the Pediatric Tuberculosis Network European Trials Group, capturing TB cases <18 years diagnosed 2000-2020. RESULTS: A total of 417 TB cases were included, comprising 139 children who are IC (human immunodeficiency virus, inborn errors of immunity, drug-induced immunosuppression, and other immunocompromising conditions) and 278 non-IC children as controls. Nonrespiratory TB was more frequent among cases than controls (32.4% vs 21.2%; P = .013). Patients with IC had an increased likelihood of presenting with severe disease (57.6% vs 38.5%; P < .001; odds ratio [95% confidence interval], 2.073 [1.37-3.13]). Children with IC had higher rates of false-negative tuberculin skin test (31.9% vs 6.0%; P < .001) and QuantiFERON-TB Gold assay (30.0% vs 7.3%; P < .001) results at diagnosis. Overall, the microbiological confirmation rate was similar in IC and non-IC cases (58.3% vs 49.3%; P = .083). Although the mortality in children with IC was <1%, the rate of long-term sequelae was significantly higher than in non-IC cases (14.8% vs 6.1%; P = .004). CONCLUSIONS: Children with IC and TB in Europe have increased rates of nonrespiratory TB, severe disease, and long-term sequelae. Immune-based TB tests have poor sensitivity in those children. Future research should focus on developing improved immunological TB tests that perform better in patients with IC, and determining the reasons for the increased risk of long-term sequelae, with the aim to design preventive management strategies.


Asunto(s)
Huésped Inmunocomprometido , Tuberculosis , Humanos , Estudios de Casos y Controles , Niño , Masculino , Femenino , Adolescente , Europa (Continente)/epidemiología , Tuberculosis/epidemiología , Tuberculosis/diagnóstico , Preescolar , Lactante , Prueba de Tuberculina , Antituberculosos/uso terapéutico
13.
Geriatr Gerontol Aging ; 18: e0000084, Apr. 2024. tab
Artículo en Inglés | LILACS | ID: biblio-1566903

RESUMEN

Dyskinesia affects the limbs, trunk, and head and is more prevalent in people with Parkinson's disease (PD) and a history of falls. More evidence about the effects of dyskinesia on postural control, balance, gait, and fall risk could help improve the quality of life of individuals with PD. This review aims to examine associations between dyskinesia and postural control, balance, gait, and fall risk in individuals with PD. Such information could lead to new approaches to quality of life improvement among individuals with PD. PubMed, CINAHL, PsycInfo, Scopus, and SciELO will be searched for longitudinal, cohort, and case-control studies published in English or Portuguese in any year that investigated the association between dyskinesia and postural control, balance, gait, and fall risk in individuals with PD. Two reviewers will independently evaluate the titles, abstracts, and full texts according to PRISMA guidelines to select eligible studies for the review. Data on participants, dyskinesia, postural control, balance, gait, and fall risk will be extracted and summarized in tables. Two reviewers will independently assess the methodological quality of each study using the Newcastle Ottawa quality assessment scale. Meta-analysis will not be performed. The results of this systematic review will offer insight into the effects of dyskinesia on postural control, balance, gait, and fall risk. Such information could significantly contribute to informed decisions about early motor intervention in individuals with PD. (AU)


Asunto(s)
Humanos , Anciano , Anciano de 80 o más Años , Enfermedad de Parkinson , Trastornos del Movimiento , Propiocepción
14.
Br J Nurs ; 33(5): 262-265, 2024 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-38446515

RESUMEN

The term 'service user' is an amorphous concept that can refer to a variety of groups. It refers to people who use or have used a service, or to the carers or parents of service users, or it can be used to refer to lay people, the public or non-professionals. It can also be used to refer to all or any combination of these. To maximise the potential of simulation, it is crucial to involve service users: their inclusion in the co-design of simulations, alongside patient educators and participatory decision-makers, provides invaluable input from a patient perspective. They also make an important contribution by portraying patients in the scenarios within which students interact, providing perspectives based on real-life experiences, offering students an insight into how patients could respond. Such an approach to designing simulations as part of nursing education will help develop professionals who are more patient-centred, culturally competent and more responsive to patient needs.


Asunto(s)
Padres , Estudiantes , Humanos , Simulación por Computador
15.
Artículo en Inglés | MEDLINE | ID: mdl-38512702

RESUMEN

BACKGROUND: Treatment of advanced differentiated thyroid carcinoma (DTC) remains a challenge as 25-50% of patients with locally invasive or distant metastatic disease become refractory to radioiodine (RAI) therapy. Tyrosine kinase inhibitors (TKI) are increasingly used in this setting. The SELECT trial demonstrated that lenvatinib, a multikinase inhibitor, significantly improved progression free survival (PFS) compared to placebo. Our aim was to report the effectiveness and safety of lenvatinib in our series of patients with advanced DTC. METHODS: A total of 25 patients with advanced DTC followed at a single tertiary center from January of 2016 to January of 2022 were retrospectively reviewed. RESULTS: Patients were treated with a mean daily dose of lenvatinib of 16.9 mg for a mean of 9.1 months. Median estimated PFS was 31.3 months. One patient achieved complete response. The objective response rate (ORR) was 40% and the disease control rate was 84%. The mean change in summed longest diameter of target lesions from baseline to nadir was -36.9%. Lenvatinib prolonged the tumor volume doubling time in 86.7% patients. Interestingly, we found that patients treated with a lower dose of lenvatinib (<16.9 mg daily) had a significantly higher PFS and ORR than patients treated with higher dosages (>16.9 mg). Adverse events were frequently reported. CONCLUSIONS: Our results confirm the effectiveness of lenvatinib in the management of patients with advanced DTC and support the need to adjust the dosage of lenvatinib to patient´s performance status and comorbidities.

17.
Biomater Adv ; 159: 213813, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38428122

RESUMEN

The ability of human tissues to self-repair is limited, which motivates the scientific community to explore new and better therapeutic approaches to tissue regeneration. The present manuscript provides a comparative study between a marine-based composite biomaterial, and another composed of well-established counterparts for bone tissue regeneration. Blue shark skin collagen was combined with bioapatite obtained from blue shark's teeth (mColl:BAp), while bovine collagen was combined with synthetic hydroxyapatite (bColl:Ap) to produce 3D composite scaffolds by freeze-drying. Collagens showed similar profiles, while apatite particles differed in their composition, being the marine bioapatite a fluoride-enriched ceramic. The marine-sourced biomaterials presented higher porosities, improved mechanical properties, and slower degradation rates when compared to synthetic apatite-reinforced bovine collagen. The in vivo performance regarding bone tissue regeneration was evaluated in defects created in femoral condyles in New Zealand rabbits twelve weeks post-surgery. Micro-CT results showed that mColl:BAp implanted condyles had a slower degradation and an higher tissue formation (17.9 ± 6.9 %) when compared with bColl:Ap implanted ones (12.9 ± 7.6 %). The histomorphometry analysis provided supporting evidence, confirming the observed trend by quantifying 13.1 ± 7.9 % of new tissue formation for mColl:BAp composites and 10.4 ± 3.2 % for bColl:Ap composites, suggesting the potential use of marine biomaterials for bone regeneration.


Asunto(s)
Materiales Biocompatibles , Andamios del Tejido , Humanos , Animales , Conejos , Bovinos , Materiales Biocompatibles/uso terapéutico , Apatitas , Regeneración Ósea , Colágeno/farmacología
18.
Br J Community Nurs ; 29(2): 60-66, 2024 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-38300245

RESUMEN

This article aims to provide an overview on loneliness in older people, with an emphasis on how insights from this body of literature can significantly contribute to the enhancement of care provided by community nurses. This review aims to provide a nuanced understanding of the factors contributing to loneliness, its impact on the physical and mental health of older individuals, and the role community nurses can play in mitigating and addressing loneliness.


Asunto(s)
Soledad , Salud Mental , Humanos , Anciano
19.
J Chromatogr A ; 1717: 464672, 2024 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-38350166

RESUMEN

The monoclonal antibody (mAb) industry is becoming increasingly digitalized. Digital twins are becoming increasingly important to test or validate processes before manufacturing. High-Throughput Process Development (HTPD) has been progressively used as a tool for process development and innovation. The combination of High-Throughput Screening with fast computational methods allows to study processes in-silico in a fast and efficient manner. This paper presents a hybrid approach for HTPD where equal importance is given to experimental, computational and decision-making stages. Equilibrium adsorption isotherms of 13 protein A and 16 Cation-Exchange resins were determined with pure mAb. The influence of other components in the clarified cell culture supernatant (harvest) has been under-investigated. This work contributes with a methodology for the study of equilibrium adsorption of mAb in harvest to different protein A resins and compares the adsorption behavior with the pure sample experiments. Column chromatography was modelled using a Lumped Kinetic Model, with an overall mass transfer coefficient parameter (kov). The screening results showed that the harvest solution had virtually no influence on the adsorption behavior of mAb to the different protein A resins tested. kov was found to have a linear correlation with the sample feed concentration, which is in line with mass transfer theory. The hybrid approach for HTPD presented highlights the roles of the computational, experimental, and decision-making stages in process development, and how it can be implemented to develop a chromatographic process. The proposed white-box digital twin helps to accelerate chromatographic process development.


Asunto(s)
Anticuerpos Monoclonales , Cromatografía , Anticuerpos Monoclonales/química , Resinas de Intercambio de Catión , Adsorción , Proteína Estafilocócica A/química , Cromatografía por Intercambio Iónico/métodos
20.
Animals (Basel) ; 14(4)2024 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-38396518

RESUMEN

The aim was to evaluate the chemical composition, carbohydrates, protein fractionation and in vitro gas production of silages composed of spineless cactus and tropical forages and their effect on sheep performance. Treatments consisted of silages: corn silage (CS), spineless cactus silage (SCS), spineless cactus + gliricidia (SCG), spineless cactus + buffel grass silage (SCBG) and spineless cactus + pornunça (SCP). Silos were opened 60 days after ensiling, and analyses were carried out. The digestibility test lasted for 36 days, with eight animals per treatment. A completely randomized design was adopted. Considering carbohydrate fractionation, CS, SCS and SCBG silages had higher total carbohydrate content (p = 0.001). The SCS silage presented a higher A + B1 fraction (p = 0.001). The SCBG and SCG silages showed a higher B2 fraction (p < 0.0001) compared to the CS and SCS silages. The SCBG and SCP silages presented a higher C fraction (p = 0.001). For protein fractionation, the SCP and SCG silages showed higher crude protein contents (p = 0.001). The CS and SCS silages showed a higher A fraction (p = 0.001). The SCBG silage presented a higher B1 + B2 fraction (p = 0.001). The SCG silage showed a higher B3 fraction (p = 0.006) compared to SCBG silage. The SCS and SCP silages showed a higher C fraction (p = 0.001). Exclusive SCS silage showed higher in vitro dry matter digestibility (p = 0.001), dry matter degradability (p = 0.001) and total gas production (p = 0.001). The use of the SCBG, SCP and SCG silages to feed sheep increased the dry matter intake (p < 0.001). Sheep fed the SCG silage showed greater dry matter and crude protein digestibility compared to the sheep fed the CS, SCS and SCP silages (p = 0.002). There was a higher water intake (p < 0.001) with the use of the SCS and SCG silages to feed the sheep. The SCP and SCG silages provided a greater intake (p < 0.001) and excretion (p < 0.001) of nitrogen by the animals. Although there were no differences between the treatments for daily gains, lambs that received the spineless cactus-based silage associated with tropical forages showed higher gains (160-190 g/day) than lambs that received CS silage (130 g/day). Thus, the use of spineless cactus associated with buffelgrass, pornunça and gliricidia to prepare mixed silages (60:40) to feed sheep has potential use to feed sheep, with positive effects on nutrient degradation and increases in dry matter intake. Under experimental conditions, we recommend the exclusive use of spineless cactus silage associated with buffel grass, pornunça and gliricidia in feeding sheep in semi-arid regions, as it provides nutrients, water and greater daily gains compared to corn silage.

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