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1.
BMB Rep ; 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38919012

RESUMO

Brain organoid is a three-dimensional (3D) tissue derived from stem cells such as induced pluripotent stem cells (iPSCs) embryonic stem cells (ESCs) that reflect real human brain structure. It replicates the complexity and development of the human brain, enabling studies of the human brain in vitro. With emerging technologies, its application is various, including disease modeling and drug screening. A variety of experimental methods have been used to study structural and molecular characteristics of brain organoids. However, electrophysiological analysis is necessary to understand their functional characteristics and complexity. Although electrophysiological approaches have rapidly advanced for monolayered cells, there are some limitations in studying electrophysiological and neural network characteristics due to the lack of 3D characteristics. Herein, electrophysiological measurement and analytical methods related to neural complexity and 3D characteristics of brain organoids are reviewed. Overall, electrophysiological understanding of brain organoids allows us to overcome limitations of monolayer in vitro cell culture models, providing deep insights into the neural network complex of the real human brain and new ways of disease modeling.

2.
Acta Neurol Belg ; 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38861245

RESUMO

BACKGROUND AND PURPOSE: Diagnosing Hashimoto's encephalopathy (HE) is challenging. In contrast to other types of autoimmune encephalitis, HE shows an excellent response to steroid treatment. We aimed to investigate the rates of antithyroid antibodies (ATAs) and probable HE in patients with unexplained mental dysfunction and compare the clinical characteristics between the good- and poor-outcome groups. METHODS: We retrospectively reviewed the medical records and electroencephalography (EEG) and neuroimaging findings of patients admitted to the Department of Neurology of our hospital from March 1, 2006, to February 28, 2023. Using our proposed diagnostic criteria for probable HE, we compared the clinical characteristics between the good- and poor-outcome groups. We also investigated the rates of ATA positivity and probable HE. RESULTS: In total, 198 patients exhibited altered mentation, rapidly progressive cognitive decline, or myoclonus. ATA tests were performed on 86 patients, and the detection rates of ATAs and probable HE were 29.1% and 25.6%, respectively. Of the 22 patients enrolled, the good- and poor-outcome groups comprised 19 and 3 patients, respectively. Clinical seizures occurred in seven patients. Nonconvulsive status epilepticus on EEG was observed in six patients, all of whom were intractable to antiepileptic drugs. Nineteen of 21 patients (90.5%) treated with immunosuppressants showed good outcomes. CONCLUSIONS: HE is a rare clinical disorder, but not as rare as previously thought. When HE is suspected, steroids should be considered the first-line treatment. Early diagnosis and adequate treatment are critical to achieve good outcomes in HE.

3.
Front Vet Sci ; 11: 1298215, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38528871

RESUMO

Brain perfusion allows for the evaluation of cerebral hemodynamics, particularly in brain infarcts and tumors. Computed tomography (CT) perfusion (CTP) provides reliable data; however, it has a limited scan field of view and radiation exposure. Magnetic resonance (MR) perfusion provides detailed imaging of small structures and a wide scan field of view. However, no study has compared CTP and MR perfusion and assessed the correlation between the perfusion parameters measured using CTP and MR perfusion. The aim of the present study was to assess the correlation and agreement of the cerebral perfusion derived from dynamic susceptibility contrast (DSC)-MRI and CTP in dogs. In this crossover design study, the cerebral blood volume (CBV), cerebral blood flow (CBF), mean transit time, and time to peak were measured in the temporal cerebral cortex, caudate nucleus, thalamus, piriform lobe, and hippocampus using CTP and DSC-MRI in six healthy beagle dogs and a dog with a pituitary tumor. On the color map of healthy beagles, blood vessels and the perivascular brain parenchyma appeared as red-green, indicating high perfusion, and the areas distant from the vessels appeared as green-blue, indicating low perfusion levels in CTP and DSC-MRI. CTP parameters were highest in the piriform lobe (CBF = 121.11 ± 12.78 mL/100 g/min and CBV = 8.70 ± 2.04 mL/100 g) and lowest in the thalamus (CBF = 63.75 ± 25.24 mL/100 g/min and CBV = 4.02 ± 0.55 mL/100 g). DSC-MRI parameters were also highest in the piriform lobe (CBF = 102.31 ± 14.73 mL/100 g/min and CBV = 3.17 ± 1.23 mL/100 g) and lowest in the thalamus (CBF = 37.73 ± 25.11 mL/100 g/min and CBV = 0.81 ± 0.44 mL/100 g) although there was no statistical correlation in the quantitative perfusion parameters between CTP and DSC-MRI. In a dog with a pituitary tumor, the color map of the tumor appeared as a red scale, indicating high perfusion and higher CBF and CBV on CTP (149 mL/100 g and 20 mL/100 g/min) and on DSC-MRI (116.3 mL/100 g and 15.32 mL/100 g/min) compared to those measured in healthy dogs. These findings indicate that DSC-MRI and CTP maps exhibit comparability and interchangeability in the assessment of canine brain perfusion.

4.
Front Vet Sci ; 11: 1298133, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38352037

RESUMO

Shoulder disease is a common cause of forelimb lameness in dogs. Determining the precise underlying cause of shoulder lameness can be challenging, especially in veterinary practice. Computerized tomography (CT) is often the preferred imaging modality for bone evaluation; however, it uses ionizing radiation and provides limited soft tissue contrast. Conversely, magnetic resonance imaging (MRI) offers excellent soft tissue contrast but has limitations in bone imaging. This study aimed to introduce a new technical innovation that enhances cortical and trabecular bone contrast on MRI, which we refer to as Fast Field Echo Resembling a CT Using Restricted Echo-Spacing (FRACTURE). In this prospective pilot study, we aimed to evaluate the use of FRACTURE, CT, and conventional MRI sequences in assessing the normal canine shoulder using a 3.0 Tesla MRI scanner. Five research beagle dogs were included, and the following pulse sequences were acquired for each dog (1): three-dimensional (3D) FRACTURE, (2) T2-weighted (T2W) images using 3D turbo spin echo (TSE), (3) T1-weighted (T1W) images using 3D TSE, (4) PD-weighted (PDW) images using 3D TSE, and (5) CT. Various parameters, including the delineation of cortical bone (intertubercular groove, greater tubercle, and lesser tubercle), conspicuity of the trabecular bone, shoulder joint visualization, and image quality, were measured for each dog and sequence. In all sequences, the shoulder joint was successfully visualized in all planes with mild motion artifacts. The intertubercular groove was best visualized on CT and FRACTURE. Both the greater and lesser tubercles were easily identified on the CT, FRACTURE, and PDW images. The trabecular pattern scored significantly higher in the CT and FRACTURE images compared to the T1W, T2W, and PDW images. Overall, the visualization of the shoulder joint was excellent in all sequences except for T1W. The use of FRACTURE in combination with conventional MRI sequences holds promise for facilitating not only soft tissue evaluation but also cortical and trabecular bone assessment. The findings from this study in normal dogs can serve as a foundation for further FRACTURE studies in dogs with shoulder diseases.

5.
JMIR Aging ; 6: e50990, 2023 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-38113067

RESUMO

BACKGROUND: Older adults often face challenges in self-managing their medication owing to physical and cognitive limitations, complex medication regimens, and packaging of medications. Emerging smart medication dispensing and adherence products (SMAPs) offer the options of automated dispensing, tracking medication intake in real time, and reminders and notifications. A 2021 review identified 51 SMAPs owing to the rapid influx of digital technology; an update to this review is required. OBJECTIVE: This review aims to identify new products and summarize and compare the key features of SMAPs. METHODS: Gray and published literature and videos were searched using Google, YouTube, PubMed, Embase, and Scopus. The first 10 pages of Google and the first 100 results of YouTube were screened using 4 and 5 keyword searches, respectively. SMAPs were included if they were able to store and allowed for the dispensation of medications, tracked real-time medication intake data, and could automatically analyze data. Products were excluded if they were stand-alone software applications, not marketed in English, not for in-home use, or only used in clinical trials. In total, 5 researchers independently screened and extracted the data. RESULTS: This review identified 114 SMAPs, including 80 (70.2%) marketed and 34 (29.8%) prototypes, grouped into 15 types. Among the marketed products, 68% (54/80) were available for consumer purchase. Of these products, 26% (14/54) were available worldwide and 78% (42/54) were available in North America. There was variability in the hardware, software, data collection and management features, and cost of the products. Examples of hardware features include battery life, medication storage capacity, availability of types and number of alarms, locking features, and additional technology required for use of the product, whereas software features included reminder and notification capabilities and availability of manufacturer support. Data capture methods included the availability of sensors to record the use of the product and data-syncing capabilities with cloud storage with short-range communications. Data were accessible to users via mobile apps or web-based portals. Some SMAPs provided data security assurance with secure log-ins (use of personal identification numbers or facial recognition), whereas other SMAPs provided data through registered email addresses. Although some SMAPs were available at set prices or free of cost to end users, the cost of other products varied based on availability, shipping fees, and subscription fees. CONCLUSIONS: An expanding market for SMAPs with features specific to at-home patient use is emerging. Health care professionals can use these features to select and suggest products that meet their patients' unique requirements.

6.
J Biotechnol ; 375: 12-16, 2023 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-37634828

RESUMO

Increasing the screening efficiency and maintaining the N-terminal cleavage pattern are key factors in the development of an in vitro synthetic signal peptide screening system for high therapeutic protein production in Chinese hamster ovary (CHO) cells. This study improved the in vitro screening system of synthetic signal peptides in CHO cells for therapeutic protein production by modifying the expression vector. Incorporating a leaky stop codon with IgG transmembrane and cytoplasmic domains into the expression vector improved the proportion of high producers in establishing stable CHO cell pools. The selected signal peptides from stable CHO cell pools that were generated using degenerate codon-based oligonucleotides with a conserved polar carboxy-terminal domain in the native signal peptide showed similar N-terminal cleavage patterns to the native one. In addition, replacing native signal peptide with selected synthetic signal peptides did not influence the sialylated N-linked glycan formation and biological activity of therapeutic Fc-fusion glycoprotein in CHO cells. Thus, an in vitro synthetic signal peptide screening system can be used for therapeutic Fc-fusion glycoprotein production in CHO cells with an enhanced specific protein productivity while maintaining the N-terminal cleavage pattern similar to the native one.


Assuntos
Oligonucleotídeos , Sinais Direcionadores de Proteínas , Animais , Cricetinae , Sinais Direcionadores de Proteínas/genética , Células CHO , Cricetulus
7.
Bioact Mater ; 27: 113-124, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37006823

RESUMO

Adsorption of proteins to nanoparticles (NPs), a complex process that results in a protein corona, is controlled by NP surface properties that define NP interactions in vivo. Efforts to control adsorbed protein quantity through surface modification have led to improvements in circulation time or biodistribution. Still, current approaches have yet to be identified to control adsorbed protein identities within the corona. Here, we report the development and characterization of diverse zwitterionic peptides (ZIPs) for NP anti-fouling surface functionalization with specific and controllable affinity for protein adsorption profiles defined by ZIP sequence. Through serum exposure of ZIP-conjugated NPs and proteomics analysis of the resulting corona, we determined that protein adsorption profiles depend not on the exact composition of the ZIPs but on the sequence and order of charges along the sequence (charge motif). These findings pave the way for developing tunable ZIPs to orchestrate specific ZIP-NP protein adsorption profiles as a function of ZIP charge motif to better control cell and tissue specificity and pharmacokinetics and provide new tools for investigating relationships between protein corona and biological function. Furthermore, overall ZIP diversity enabled by the diversity of amino acids may ameliorate adaptive immune responses.

8.
Clin Exp Otorhinolaryngol ; 16(1): 87-94, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36521487

RESUMO

OBJECTIVES: Voice abuse in noisy environments can result in voice disorders. However, insufficient studies have sought to differentiate vocal cord lesions through laryngoscopic examinations among workers in noisy environments. This study investigated the relationship between a history of noise exposure in the workplace and benign vocal fold lesions (BVFLs). METHODS: We used Korea National Health and Nutrition Examination Survey data from 2010 to 2012. The chi-square test was used to compare characteristics between two groups according to the presence or absence of BVFLs. To investigate the association between BVFLs and noise exposure in the workplace, we calculated adjusted odds ratios and 95% confidence intervals (CIs) using multiple logistic regression analysis. RESULTS: In total, 10,170 participants with available laryngoscopy. RESULTS: were enrolled. Smoking history, hypertension, diabetes, and exposure to noise for more than 3 months at the workplace were significantly more common in participants with BVFLs. After adjusting for age, sex, smoking, drinking, obesity, hypertension, diabetes, income, education, and occupation as confounders, we confirmed that BVFLs were 1.52 times more likely (95% CI, 1.157-1.990) to occur in individuals with occupational noise exposure. CONCLUSION: Working in a noisy environment could induce BVFLs in workers through voice abuse. Social recognition that a noisy environment is a risk factor for BVFLs needs to be improved, and preventive measures should be implemented.

9.
J Vis Exp ; (189)2022 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-36533837

RESUMO

Supercapacitors (SC) have attracted attention as energy storage devices due to their high density and long cycle performance. SCs used in devices operating in stretchable systems require stretchable electrolytes. Gel polymer electrolytes (GPEs) are an ideal replacement for liquid electrolytes. Polyvinyl alcohol (PVA) and polyvinylidene fluoride-co-hexafluoropropylene (PVDF-HFP) have been widely applied as a polymer-matrix-based electrolytes for supercapacitors because of their low cost, chemically stable, wide operating temperature range, and high ionic conductivities. Herein, we describe the procedures for (1) synthesizing a gel polymer electrolyte with PVA and PVDF-HFP, (2) measuring the electrochemical stability of the gel polymer electrolytes by cyclic voltammetry (CV), (3) measuring the ionic conductivity of the gel polymer electrolytes by electrochemical impedance spectroscopy (EIS), (4) assembling symmetric coin cells using activated carbon (AC) electrodes with the PVA- and PVDF-HFP-based gel polymer electrolytes, and (5) evaluating the electrochemical performance using galvanostatic charge-discharge analysis (GCD) and CV at 25 °C. Additionally, we describe the challenges and insights gained from these experiments.

10.
J Biol Chem ; 298(11): 102519, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36152752

RESUMO

Plants and algae are faced with a conundrum: harvesting sufficient light to drive their metabolic needs while dissipating light in excess to prevent photodamage, a process known as nonphotochemical quenching. A slowly relaxing form of energy dissipation, termed qH, is critical for plants' survival under abiotic stress; however, qH location in the photosynthetic membrane is unresolved. Here, we tested whether we could isolate subcomplexes from plants in which qH was induced that would remain in an energy-dissipative state. Interestingly, we found that chlorophyll (Chl) fluorescence lifetimes were decreased by qH in isolated major trimeric antenna complexes, indicating that they serve as a site for qH-energy dissipation and providing a natively quenched complex with physiological relevance to natural conditions. Next, we monitored the changes in thylakoid pigment, protein, and lipid contents of antenna with active or inactive qH but did not detect any evident differences. Finally, we investigated whether specific subunits of the major antenna complexes were required for qH but found that qH was insensitive to trimer composition. Because we previously observed that qH can occur in the absence of specific xanthophylls, and no evident changes in pigments, proteins, or lipids were detected, we tentatively propose that the energy-dissipative state reported here may stem from Chl-Chl excitonic interaction.


Assuntos
Clorofila , Complexos de Proteínas Captadores de Luz , Complexo de Proteína do Fotossistema II , Plantas , Clorofila/química , Luz , Complexos de Proteínas Captadores de Luz/química , Fotossíntese , Complexo de Proteína do Fotossistema II/química , Plantas/química , Tilacoides/química , Xantofilas/química
11.
Micromachines (Basel) ; 13(7)2022 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-35888929

RESUMO

The increasing use of rapidly fluctuating renewable energy sources, such as sunlight, has necessitated the use of supercapacitors, which are a type of energy storage system with high power. Chemically exfoliated graphene oxide (GO) is a representative starting material in the fabrication of supercapacitor electrodes based on reduced GO (rGO). However, the restacking of rGO sheets driven by π-π stacking interactions leads to a significant decrease in the electrochemically active surface area, leading to a loss of energy density. Here, to effectively inhibit restacking and construct a three-dimensional wrinkled structure of rGO (3DWG), we propose an agarose gel-templating method that uses agarose gel as a soft and removable template. The 3DWG, prepared via the sequential steps of gelation, freeze-drying, and calcination, exhibits a macroporous 3D structure and 5.5-fold higher specific capacitance than that of rGO restacked without the agarose template. Further, we demonstrate a "gel-stamping" method to fabricate thin-line patterned 3DWG, which involves the gelation of the GO-agarose gel within micrometer-sized channels of a customized polydimethylsiloxane (PDMS) mold. As an easy and low-cost manufacturing process, the proposed agarose gel templating method could provide a promising strategy for the 3D structuring of rGO.

12.
Genetics ; 221(3)2022 07 04.
Artigo em Inglês | MEDLINE | ID: mdl-35657327

RESUMO

35S rRNA transcripts include a 5'-external transcribed spacer followed by rRNAs of the small and large ribosomal subunits. Their processing yields massive precursors that include dozens of assembly factor proteins. In Saccharomyces cerevisiae, nucleolar assembly factors form 2 coaxial layers/volumes around ribosomal DNA. Most of these factors are cyclically recruited from a latent state to an operative state, and are extensively conserved. The layers match, at least approximately, known subcompartments found in higher eukaryotic cells. ∼80% of assembly factors are essential. The number of copies of these assembly factors is comparable to the number of nascent transcripts. Moreover, they exhibit "isoelectric balance," with RNA-binding candidate "nucleator" assembly factors being notably basic. The physical properties of pre-small subunit and pre-large subunit assembly factors are similar, as are their 19 motif signatures detected by hierarchical clustering, unlike motif signatures of the 5'-external transcribed spacer rRNP. Additionally, many assembly factors lack shared motifs. Taken together with the progression of rRNP composition during subunit maturation, and the realization that the ribosomal DNA cable is initially bathed in a subunit-nonspecific assembly factor reservoir/microenvironment, we propose a "3-step subdomain assembly model": Step (1): predominantly basic assembly factors sequentially nucleate sites along nascent rRNA; Step (2): the resulting rRNPs recruit numerous less basic assembly factors along with notably basic ribosomal proteins; Step (3): rRNPs in nearby subdomains consolidate. Cleavages of rRNA then promote release of rRNPs to the nucleoplasm, likely facilitated by the persistence of assembly factors that were already associated with nucleolar precursors.


Assuntos
Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae , Nucléolo Celular/genética , Nucléolo Celular/metabolismo , DNA Ribossômico/genética , DNA Ribossômico/metabolismo , Precursores de RNA/genética , RNA Ribossômico/genética , Proteínas Ribossômicas/genética , Proteínas Ribossômicas/metabolismo , Ribossomos/genética , Ribossomos/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo
13.
Korean J Chem Eng ; 39(6): 1632-1640, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35125591

RESUMO

Ag-doped ZnO nanoparticles (AZNs) were directly synthesized using sol-gel method to embed into polyacrylonitrile (PAN) nanofibers by electrospinning. The synthesized AZNs were optically and structurally characterized by UV-VIS spectroscopy, photoluminescence spectroscopy, high resolution HR-TEM and XRD. The photocatalytic activity of the AZNs was examined by photocatalytic degradation of methylene blue to correlate with their antiviral efficacy in PAN nanofibers fabricated via electrospinning technique. The PAN nanofibers containing AZNs were characterized using SEM and EDS. Finally, antiviral activity of AZNs/PAN nanofibers was investigated by using virus ϕx174 under visible light irradiation. As a result, the antiviral efficacy of nanofibers increased as the concentration of Ag in AZNs increased. The results show that better antiviral efficacy was obtained in AZNs/PAN nanofibers prepared with AZNs of higher photocatalytic performance.

14.
Front Bioeng Biotechnol ; 10: 773004, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35155388

RESUMO

We have recently identified novel small molecules, Oxo-M and 4-PPBP, which specifically stimulate endogenous tendon stem/progenitor cells (TSCs), leading to potential regenerative healing of fully transected tendons. Here, we investigated an injectable, multidomain peptide (MDP) hydrogel providing controlled delivery of the small molecules for regenerative tendon healing. We investigated the release kinetics of Oxo-M and 4-PPBP from MDP hydrogels and the effect of MDP-released small molecules on tenogenic differentiation of TSCs and in vivo tendon healing. In vitro, MDP showed a sustained release of Oxo-M and 4-PPBP and a slower degradation than fibrin. In addition, tenogenic gene expression was significantly increased in TSC with MDP-released Oxo-M and 4-PPBP as compared to the fibrin-released. In vivo, MDP releasing Oxo-M and 4-PPBP significantly improved tendon healing, likely associated with prolonged effects of Oxo-M and 4-PPBP on suppression of M1 macrophages and promotion of M2 macrophages. Comprehensive analyses including histomorphology, digital image processing, and modulus mapping with nanoindentation consistently suggested that Oxo-M and 4-PPBP delivered via MDP further improved tendon healing as compared to fibrin-based delivery. In conclusion, MDP delivered with Oxo-M and 4-PPBP may serve as an efficient regenerative therapeutic for in situ tendon regeneration and healing.

15.
Environ Res ; 204(Pt B): 112036, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34529972

RESUMO

A practical scale photocatalytic air purifier equipped with a TiO2/H-ZSM-5 composite bead filter was demonstrated to be able to effectively remove indoor volatile organic compounds (VOCs) and viruses with sustainable performances under UVA-LED illumination. TiO2 hybridized with 5 wt% H-ZSM-5 zeolite significantly enhanced its photocatalytic activity for degrading VOCs including formaldehyde, acetaldehyde, and toluene, than bare TiO2. H-ZSM-5 provided strong adsorption sites for these compounds, thus accelerating their photocatalytic conversion into CO2 by adjacent TiO2 photocatalyst. Moreover, owing to its superior adsorption capacity, the composite bead filter completely prevented the emission of formaldehyde produced by photocatalytic oxidation of toluene. The sustainability of this composite bead filter for VOC removal was confirmed by regeneration and accelerated durability tests. In addition, the photocatalytic air purifier was effective in removing aerosolized viral particles of bacteriophage Phi-X 174. It was confirmed that the viruses on filter surfaces were completely inactivated by photocatalytic oxidation. TiO2/H-ZSM-5 composite beads also exhibited excellent efficacies for inactivation of pathogenic coronaviruses including SARS-CoV-2. The photocatalytic process degraded viral RNAs of SARS-CoV-2 by more than 99.999% in 1 h, eliminating the viral infectivity. Results of this study suggest that the air purifier equipped with the composite bead filter is ready for practical applications for home and hospital uses.


Assuntos
Filtros de Ar , COVID-19 , Compostos Orgânicos Voláteis , Zeolitas , Catálise , Humanos , SARS-CoV-2 , Titânio , Inativação de Vírus
16.
Xenotransplantation ; 28(3): e12667, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33438288

RESUMO

BACKGROUND: Necrostatin-1 (Nec-1) supplementation to tissue culture media on day 3 has recently been shown to augment the insulin content, endocrine cellular composition, and insulin release of pre-weaned porcine islets (PPIs); however, its effects were only examined for the first 7 days of tissue culture. The present study examined whether the addition of Nec-1 on day 3 could further enhance the in vitro development and function of PPIs after 14 days of tissue culture. METHODS: PPIs were isolated from 8- to 15-day-old, pre-weaned Yorkshire piglets and cultured in an islet maturation media supplemented with Nec-1 on day 3. The recovery, viability, insulin content, endocrine cellular composition, GLUT2 expression in beta cells, differentiation and proliferation potential, and glucose-stimulated insulin secretion of PPIs were assessed on days 3, 7, and 14 of tissue culture (n = 5 on each day). RESULTS: Compared with day 7 of tissue culture, islets on day 14 had a lower recovery, GLUT2 expression in beta cells, proliferation capacity of endocrine cells, and glucose-induced insulin stimulation index. Prolonging the culture time to 14 days did not affect islet viability, insulin content, proportion of endocrine cells, and differentiation potential. CONCLUSION: The growth-inducing effects of Nec-1 on PPIs were most effective on day 7 of tissue culture when added on day 3. Our findings support existing evidence that the in vitro activities of Nec-1 are short-lived and encourage future studies to explore the use of other novel growth factors during prolonged islet tissue culture.


Assuntos
Ilhotas Pancreáticas , Animais , Imidazóis , Indóis , Insulina/metabolismo , Secreção de Insulina , Ilhotas Pancreáticas/metabolismo , Suínos , Transplante Heterólogo
17.
Cell Transplant ; 29: 963689720977835, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33267618

RESUMO

For the advancement of porcine xenotransplantation for clinical use in type 1 diabetes mellitus, the concerns of a sustainable and safe digestion enzyme blend must be overcome. Incorporating good manufacturing practices (GMP) can facilitate this through utilizing GMP-grade enzymes. In conjunction, still taking into account the cost-effectiveness, a wide concern. We evaluated how GMP-grade enzyme blends impact our piglet islets and their long-term effects. Preweaned porcine islets (PPIs) were isolated from 8- to 10-day-old pigs. Digestion enzyme blends, collagenase type V (Type V), collagenase AF-1 GMP-grade with collagenase NB 6 GMP-grade (AF-1 and NB 6), and collagenase AF-1 GMP-grade with collagenase neutral protease AF GMP-grade (AF-1 and NP AF) were compared. Islet quality control assessments, islet yield, viability, and function, were performed on days 3 and 7, and cell content was performed on day 7. GMP-grade AF-1 and NB 6 (17,209 ± 2,730 islet equivalent per gram of pancreatic tissue [IE/g] on day 3, 9,001 ± 1,034 IE/g on day 7) and AF-1 and NP AF (17,214 ± 3,901 IE/g on day 3, 8,833 ± 2,398 IE/g on day 7) showed a significant increase in islet yield compared to Type V (4,618 ± 1,240 IE/g on day 3, 1,923 ± 704 IE/g on day 7). Islet size, viability, and function showed comparable results in all enzyme blends. There was no significant difference in islet cellular content between enzyme blends. This study demonstrated a comparison of GMP-grade collagenase enzyme blends and a standard crude collagenase enzyme in preweaned-aged porcine, a novel topic in this age. GMP-grade enzyme blends of AF-1 and NB 6 and AF-1 and NP AF resulted in substantially higher yields and as effective PPIs compared to Type V. In the long run, considering costs, integrity, and sustainability, GMP-grade enzyme blends are more favorable for clinical application due to high reproducibility in comparison to undefined manufacturing processes of standard enzymes.


Assuntos
Colagenases/farmacologia , Ilhotas Pancreáticas/efeitos dos fármacos , Ilhotas Pancreáticas/metabolismo , Animais , Ilhotas Pancreáticas/fisiologia , Transplante das Ilhotas Pancreáticas , Pâncreas , Suínos , Sobrevivência de Tecidos/fisiologia
18.
Pharmaceutics ; 12(11)2020 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-33202709

RESUMO

A micro/nanobubble (MNB) refers to a bubble structure sized in a micrometer or nanometer scale, in which the core is separated from the external environment and is normally made of gas. Recently, it has been confirmed that MNBs can be widely used in angiography, drug delivery, and treatment. Thus, MNBs are attracting attention as they are capable of constructing a new contrast agent or drug delivery system. Additionally, in order to effectively use an MNB, the method of securing its stability is also being studied. This review highlights the factors affecting the stability of an MNB and the stability of the MNB within the ultrasonic field. It also discusses the relationship between the stability of the bubble and its applicability in vivo.

19.
Biotechnol J ; 15(12): e2000079, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32678938

RESUMO

The topical delivery of siRNA-based therapies has opened new avenues for the treatment of skin disorders. The use of siRNA as a therapeutic, however, is limited due to its rapid degradation and poor cellular uptake. Furthermore, the top layer of skin, the stratum corneum, is a major barrier to the delivery of topical agents. There is an unmet need for efficient topical formulations for delivering siRNA to the site of action. In this study, 1,2-dioleoyl-3-trimethylammonium-propane (DOTAP) or lipofectamine is used to prepare a nanocarrier for delivering siRNA against glyceraldehyde 3-phosphate dehydrogenase (GAPDH); GAPDH expression is then evaluated at the cellular level. In addition, a dermal transport assay is designed and implemented to evaluate the penetration and delivery efficacy of siRNA in pig skin using lipid nanocarriers. The delivery of siRNA with the use of a lipid nanocarrier is significantly better than the delivery of siRNA without it. Thus, the findings identify lipid nanocarriers as excellent candidates for the transdermal delivery of siRNA for gene silencing in the skin and thus for applications in related preclinical models.


Assuntos
Lipídeos , Administração Cutânea , Animais , Inativação Gênica , RNA Interferente Pequeno/genética , Pele , Suínos
20.
Open Biol ; 9(4): 190043, 2019 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-30966997

RESUMO

The rapid response of photosynthetic organisms to fluctuations in ambient light intensity is incompletely understood at both the molecular and membrane levels. In this review, we describe research from our group over a 10-year period aimed at identifying the photophysical mechanisms used by plants, algae and mosses to control the efficiency of light harvesting by photosystem II on the seconds-to-minutes time scale. To complement the spectroscopic data, we describe three models capable of describing the measured response at a quantitative level. The review attempts to provide an integrated view that has emerged from our work, and briefly looks forward to future experimental and modelling efforts that will refine and expand our understanding of a process that significantly influences crop yields.


Assuntos
Complexos de Proteínas Captadores de Luz/metabolismo , Luz , Fotossíntese/efeitos da radiação , Complexo de Proteína do Fotossistema II/metabolismo , Plantas/metabolismo , Plantas/efeitos da radiação , Algoritmos , Clorofila/metabolismo , Transferência de Energia , Modelos Biológicos , Fotoquímica
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