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1.
Nanotechnology ; 35(29)2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38621372

RESUMO

A hierarchical sea urchin-like hybrid metal oxide nanostructure of ZnO nanorods deposited on TiO2porous hollow hemispheres with a thin zinc titanate interface layer is specifically designed and synthesized to form a combined type I straddling and type II staggered junctions. The HHSs, synthesized by electrospinning, facilitate light trapping and scattering. The ZnO nanorods offer a large surface area for improved surface oxidation kinetics. The interface layer of zinc titanate (ZnTiO3) between the TiO2HHSs and ZnO nanorods regulates the charge separation in a closely coupled hierarchy structure of ZnO/ZnTiO3/TiO2. The synergistic effects of the improved light trapping, charge separation, and fast surface reaction kinetics result in a superior photoconversion efficiency of 1.07% for the photoelectrochemical water splitting with an outstanding photocurrent density of 2.8 mA cm-2at 1.23 V versus RHE.

2.
BMC Genomics ; 24(1): 590, 2023 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-37794337

RESUMO

BACKGROUND: Receptivity of the uterus is essential for embryo implantation and progression of mammalian pregnancy. Acquisition of receptivity involves major molecular and cellular changes in the endometrial lining of the uterus from a non-receptive state at ovulation, to a receptive state several days later. The precise molecular mechanisms underlying this transition and their upstream regulators remain to be fully characterized. Here, we aimed to generate a comprehensive profile of the endometrial transcriptome in the peri-ovulatory and peri-implantation states, to define the genes and gene pathways that are different between these states, and to identify new candidate upstream regulators of this transition, in the mouse. RESULTS: High throughput RNA-sequencing was utilized to identify genes and pathways expressed in the endometrium of female C57Bl/6 mice at estrus and on day 3.5 post-coitum (pc) after mating with BALB/c males (n = 3-4 biological replicates). Compared to the endometrium at estrus, 388 genes were considered differentially expressed in the endometrium on day 3.5 post-coitum. The transcriptional changes indicated substantial modulation of uterine immune and vascular systems during the pre-implantation phase, with the functional terms Angiogenesis, Chemotaxis, and Lymphangiogenesis predominating. Ingenuity Pathway Analysis software predicted the activation of several upstream regulators previously shown to be involved in the transition to receptivity including various cytokines, ovarian steroid hormones, prostaglandin E2, and vascular endothelial growth factor A. Our analysis also revealed four candidate upstream regulators that have not previously been implicated in the acquisition of uterine receptivity, with growth differentiation factor 2, lysine acetyltransferase 6 A, and N-6 adenine-specific DNA methyltransferase 1 predicted to be activated, and peptidylprolyl isomerase F predicted to be inhibited. CONCLUSIONS: This study confirms that the transcriptome of a receptive uterus is vastly different to the non-receptive uterus and identifies several genes, regulatory pathways, and upstream drivers not previously associated with implantation. The findings will inform further research to investigate the molecular mechanisms of uterine receptivity.


Assuntos
Transcriptoma , Fator A de Crescimento do Endotélio Vascular , Gravidez , Masculino , Feminino , Camundongos , Animais , Fator A de Crescimento do Endotélio Vascular/metabolismo , Endométrio/metabolismo , Implantação do Embrião/genética , Útero , Mamíferos/genética
3.
J Endovasc Ther ; : 15266028231173311, 2023 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-37191262

RESUMO

PURPOSE: We describe the feasibility and early results of a novel endovascular approach with a surgeon-modified fenestrated iliac stent graft to preserve pelvic perfusion in patients with iliac aneurysms not suitable for iliac branch devices (IBDs). TECHNIQUE: Seven high-risk patients, median age 76 years (range 63-83), with a complex aortoiliac anatomy with contraindications for commercially available IBDs were treated with a novel surgeon-modified fenestrated iliac stent graft between August 2020 and November 2021. The modified device was built using an iliac limb stent graft (Endurant II Stent Graft; Medtronic), which was partially deployed, surgically fenestrated with a scalpel, reinforced, re-sheathed, and inserted via femoral access. The internal iliac artery was cannulated and bridged with a covered stent. Technical success rate was 100%. After a median follow-up period of 10 months, there was 1 type II endoleak and no migrations, stent fractures, or loss of device integrity. One iliac limb occlusion occurred after 7 months, which needed a secondary endovascular intervention, restoring patency. CONCLUSION: Surgeon-modified fenestrated iliac stent graft is feasible and might be used as an alternative in patients with a complex iliac anatomy not suitable to commercially available IBDs. Long-term follow-up is needed to evaluate stent graft patency and potential complications. CLINICAL IMPACT: Surgeon modified fenetrated iliac stent grafts might be a promising alternative to iliac branch devices, extending endovascular solutions to a broader patient population with complex aorto-iliac anatomies preserving antegrade internal iliac artery perfusion. It is possible to treat small iliac bifurcations and large angulations of the iliac bifurcation safely and there is no need for a contralateral or upper-extremity access.

4.
Phys Chem Chem Phys ; 25(16): 11253-11260, 2023 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-37060133

RESUMO

Photocatalytic water splitting has recently received increasing attention as a green fuel source. The controlled nano-geometry of the photocatalytic material can improve light harvesting. In this study, as a proof of concept, hollow hemisphere (HHS)-based films of TiO2 material were created by a conventional electrospray method and subsequently applied for photoelectrochemical (PEC) water splitting. To preserve the morphology of the HHS structure, a hydrolysis precipitation phase separation method (HPPS) was developed. As a result, the TiO2 HHS-based thin films presented a maximum PEC water splitting efficiency of ca. 0.31%, almost two times that of the photoanode formed by TiO2 nanoparticle-based films (P25). The unique morphology and porous structure of the TiO2 HHSs with reduced charge recombination and improved light absorption are responsible for the enhanced PEC performance. Light scattering by the HHS was demonstrated with total reflection internal fluorescence microscopy (TRIFM), revealing the unique light trapping phenomenon within the HHS cavity. This work paves the way for the rational design of nanostructures for photocatalysis in fields including energy, environment, and organosynthesis.

5.
Surg Endosc ; 36(11): 8672-8683, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35697855

RESUMO

BACKGROUND: We developed laparoscopic transfistulous bile duct exploration (LTBDE) for Mirizzi syndrome (MS) McSherry type II in September 2011. Then, single-incision LTBDE (SILTBDE) was adopted as a preferred technique since August 2013. This retrospective study aims to analyze the outcome of LTBDE in 7.7 years and to compare SILTBDE with four-incision LTBDE (4ILTBDE). METHODS: Seventeen consecutive patients underwent LTBDE for MS McSherry type II from September 2011 to May 2019. Transfistulous removal of the impacted stone(s), choledochoscopic bile duct exploration, and primary closure of the gallbladder remnant were performed without biliary drainage. RESULTS: The sex ratio is 12:5 (male: female) with an average age of 39.4 ± 10.3 (24-56) years. Ten patients (58.8%) had their diagnoses of MS established by preoperative imaging. According to the Csendes classification, three type II (17.6%), nine type III (52.9%), and five type IV (29.4%) were identified. The operative time was 264.8 ± 60.3 min (156-358 min). The stone clearance rate was 100%. The postoperative hospital stay was 4.7 ± 1.9 (2-10) days. No procedure was converted to an open operation. Two postoperative transient hyperamylasemia (11.8%) and one superficial wound infection (5.9%) occurred and all recovered well under conservative treatment (Clavien-Dindo grade I). During an average 2.2-year follow-up period, no biliary stricture or stone recurrence occurred. No significant difference exists between the SILTBDE and 4ILTBDE groups. Nevertheless, an insignificant trend of shorter postoperative hospital stay was observed in the former. A diagnosis of MS Csendes type IV implicates prolonged total and postoperative hospital stays (p < 0.01). CONCLUSIONS: LTBDE is safe and efficacious for MS McSherry type II. It provides a simple solution for various types of MS and avoids undesirable complications following bilioenteric anastomosis. SILTBDE is comparable to 4ILTBDE for selected patients. Patients with MS Csendes type IV need more time to recover after surgery.


Assuntos
Laparoscopia , Síndrome de Mirizzi , Ferida Cirúrgica , Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Síndrome de Mirizzi/cirurgia , Estudos Retrospectivos , Ducto Colédoco/cirurgia , Ductos Biliares , Laparoscopia/métodos
6.
Sensors (Basel) ; 22(23)2022 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-36501919

RESUMO

Regressing the distribution of different sub-populations from a batch of images with learning algorithms is not a trivial task, as models tend to make errors that are unequally distributed across the different sub-populations. Obviously, the baseline is forming a histogram from the batch after having characterized each image independently. However, we show that this approach can be strongly improved by making the model aware of the ultimate task thanks to a density loss for both sub-populations related to classes (on three public datasets of image classification) and sub-populations related to size (on two public datasets of object detection in image). For example, class distribution was improved two-fold on the EUROSAT dataset and size distribution was improved by 10% on the PASCAL VOC dataset with both RESNET and VGG backbones. The code is released in the GitHub archive at achanhon/AdversarialModel/tree/master/proportion.


Assuntos
Aprendizado Profundo , Redes Neurais de Computação , Algoritmos , Demografia
7.
Int J Mol Sci ; 23(16)2022 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-36012314

RESUMO

Pre-mRNA processing factors (PRPFs) are vital components of the spliceosome and are involved in the physiological process necessary for pre-mRNA splicing to mature mRNA. As an important member, PRPF6 mutation resulting in autosomal dominant retinitis pigmentosa (adRP) is not common. Recently, we reported the establishment of an induced pluripotent stem cells (iPSCs; CSUASOi004-A) model by reprogramming the peripheral blood mononuclear cells of a PRPF6-related adRP patient, which could recapitulate a consistent disease-specific genotype. In this study, a disease model of retinal pigment epithelial (RPE) cells was generated from the iPSCs of this patient to further investigate the underlying molecular and pathological mechanisms. The results showed the irregular morphology, disorganized apical microvilli and reduced expressions of RPE-specific genes in the patient's iPSC-derived RPE cells. In addition, RPE cells carrying the PRPF6 mutation displayed a decrease in the phagocytosis of fluorescein isothiocyanate-labeled photoreceptor outer segments and exhibited impaired cell polarity and barrier function. This study will benefit the understanding of PRPF6-related RPE cells and future cell therapy.


Assuntos
Células-Tronco Pluripotentes Induzidas , Retinose Pigmentar , Diferenciação Celular/genética , Células Epiteliais/metabolismo , Humanos , Leucócitos Mononucleares/metabolismo , Mutação , Precursores de RNA/metabolismo , Fatores de Processamento de RNA/genética , Epitélio Pigmentado da Retina/metabolismo , Pigmentos da Retina/metabolismo , Retinose Pigmentar/metabolismo , Fatores de Transcrição/metabolismo
8.
J Environ Manage ; 322: 116089, 2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-36070650

RESUMO

The relationship between the two sustainable development goals (SDGs)-inequality reduction and carbon emission reduction is critical for governments formulating and implementing environmental and redistribution policies. This study uses micro survey data from the China Family Panel Studies (CFPS) to conduct a counterfactual analysis that decomposes and quantifies the net effects of consumption growth, redistribution, and changing patterns of consumption on household carbon emissions. The counterfactual approach helps to overcome the endogeneity concerns. The findings of our study convey a profoundly important and alarming message: the redistribution measures for inequality reduction may increase household carbon emissions. The findings attest to the need for Chinese policymakers to seriously consider the trade-off between inequality reduction and emission reduction, particularly in certain regions in China. To address the trade-off, one key measure is to encourage low-carbon lifestyles and consumption patterns to ensure that the benefits gained by poorer households from redistribution measures will not translate into higher emissions.


Assuntos
Dióxido de Carbono , Carbono , Carbono/análise , Dióxido de Carbono/análise , China , Desenvolvimento Econômico , Governo
9.
Am J Pathol ; 190(5): 977-993, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32084371

RESUMO

Animal models of cystic fibrosis (CF) are essential for investigating disease mechanisms and trialing potential therapeutics. This study generated two CF rat models using clustered regularly interspaced short palindromic repeats/clustered regularly interspaced short palindromic repeats-associated protein 9 gene editing. One rat model carries the common human Phe508del (ΔF508) CF transmembrane conductance regulator (CFTR) mutation, whereas the second is a CFTR knockout model. Phenotype was characterized using a range of functional and histologic assessments, including nasal potential difference to measure electrophysiological function in the upper airways, RNAscope in situ hybridization and quantitative PCR to assess CFTR mRNA expression in the lungs, immunohistochemistry to localize CFTR protein in the airways, and histopathologic assessments in a range of tissues. Both rat models revealed a range of CF manifestations, including reduced survival, intestinal obstruction, bioelectric defects in the nasal epithelium, histopathologic changes in the trachea, large intestine, and pancreas, and abnormalities in the development of the male reproductive tract. The CF rat models presented herein will prove useful for longitudinal assessments of pathophysiology and therapeutics.


Assuntos
Regulador de Condutância Transmembrana em Fibrose Cística/deficiência , Fibrose Cística , Modelos Animais de Doenças , Edição de Genes/métodos , Animais , Sistemas CRISPR-Cas , Fibrose Cística/genética , Fibrose Cística/patologia , Regulador de Condutância Transmembrana em Fibrose Cística/genética , Humanos , Camundongos Knockout , Mutação , Fenótipo , Ratos , Ratos Sprague-Dawley
10.
J Endovasc Ther ; 28(6): 871-877, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34190634

RESUMO

PURPOSE: To describe the use of large-diameter balloon-expandable stent-grafts (BeGraft aortic stent-graft, Bentley InnoMed GmbH, Hechingen, Germany) in the treatment of infrarenal penetrating aortic ulcer (iPAU). MATERIALS AND METHODS: Retrospective analysis of patients undergoing endovascular treatment with the BeGraft aortic stent-graft in 8 European centers from January 2017 to October 2020. Demographics, perioperative data, and midterm outcomes were collected. Endpoints of the study were technical feasibility, early mortality, and morbidity. RESULTS: A total of 40 patients were included. The mean age was 73.9±7.05 years and 63.2% were male. Indications for treatment included size and morphology (65%), presence of symptoms (29.5%), and contained ruptures (5.5%). Urgent treatment was performed in 5% of cases. Technical success was 97.5%. Median operation time was 58 minutes (19-170 minutes), with 27.5% of patients having additional procedures during the main intervention (1 additional repair with a C-TAG (W.L. Gore & Associates, Inc, Flagstaff, AZ, USA) thoracic endoprosthesis, 5 covered endovascular reconstruction of aortic bifurcation procedures, 3 extensions with proximal cuffs, and 2 percutaneous angioplasties of the common iliac arteries). Percutaneous femoral access was used in 72.5%, while groin cut-down was performed in 27.5%. Repair was successful with only 1 stent in 45% of cases, while 37.5% required 2 stents and nearly 17.5% required 3/4 stent-grafts. The 30-day mortality was 0%, with a 2.5% reintervention rate (1 patient required evacuation of an intra-abdominal hematoma). Median follow-up was 13.9 months (2-39 months), during which no vascular-related reinterventions or deaths were reported. In 4 patients, a type II endoleak was observed. No cases of graft migration, thrombosis, or stent-fracture were observed. CONCLUSIONS: The treatment of iPAU with the BeGraft aortic stent-graft in a selective patient group is feasible with low rate of perioperative morbidity and mortality. Balloon-expandable stent-grafts offer the option to repair iPAUs with a shorter coverage of the aorta using low-profile sheath, that enables treatment in the presence of calcified access vessels and small diameter aortic bifurcations.


Assuntos
Implante de Prótese Vascular , Procedimentos Endovasculares , Idoso , Idoso de 80 Anos ou mais , Prótese Vascular , Implante de Prótese Vascular/efeitos adversos , Procedimentos Endovasculares/efeitos adversos , Humanos , Masculino , Desenho de Prótese , Estudos Retrospectivos , Stents , Resultado do Tratamento , Úlcera/diagnóstico por imagem , Úlcera/cirurgia
11.
Proc Natl Acad Sci U S A ; 115(29): 7503-7508, 2018 07 17.
Artigo em Inglês | MEDLINE | ID: mdl-29967135

RESUMO

The surfaces of many hollow or tubular tissues/organs in our respiratory, gastrointestinal, and urogenital tracts are covered by mucosa with folded patterns. The patterns are induced by mechanical instability of the mucosa under compression due to constrained growth. Recapitulating this folding process in vitro will facilitate the understanding and engineering of mucosa in various tissues/organs. However, scant attention has been paid to address the challenge of reproducing mucosal folding. Here we mimic the mucosal folding process using a cell-laden hydrogel film attached to a prestretched tough-hydrogel substrate. The cell-laden hydrogel constitutes a human epithelial cell lining on stromal component to recapitulate the physiological feature of a mucosa. Relaxation of the prestretched tough-hydrogel substrate applies compressive strains on the cell-laden hydrogel film, which undergoes mechanical instability and evolves into morphological patterns. We predict the conditions for mucosal folding as well as the morphology of and strain in the folded artificial mucosa using a combination of theory and simulation. The work not only provides a simple method to fold artificial mucosa but also demonstrates a paradigm in tissue engineering via harnessing mechanical instabilities guided by quantitative mechanics models.


Assuntos
Células Epiteliais/metabolismo , Hidrogéis/química , Modelos Biológicos , Engenharia Tecidual , Linhagem Celular Tumoral , Células Epiteliais/citologia , Humanos , Mucosa/citologia , Mucosa/metabolismo
12.
Psychogeriatrics ; 21(3): 396-406, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33594793

RESUMO

Alzheimer's disease (AD) is the commonest cause of dementia, characterized by the clinical presentation of progressive anterograde episodic memory impairment. However, atypical presentation of patients is increasingly recognized. These atypical AD include logopenic aphasia, behavioural variant AD, posterior cortical atrophy, and corticobasal syndrome. These atypical AD are more common in patients with young onset AD before the age of 65 years old. Since medical needs (including the behavioural and psychological symptoms of dementia) of atypical AD patients could be different from typical AD patients, it is important for clinicians to be aware of these atypical forms of AD. In addition, disease modifying treatment may be available in the future. This review aims at providing an update on various important subtypes of atypical AD including behavioural and psychological symptoms.


Assuntos
Doença de Alzheimer , Idoso , Doença de Alzheimer/diagnóstico , Atrofia , Humanos
13.
Adv Funct Mater ; 30(49)2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34483808

RESUMO

Light is a particularly appealing tool for on-demand drug delivery due to its noninvasive nature, ease of application and exquisite temporal and spatial control. Great progress has been achieved in the development of novel light-driven drug delivery strategies with both breadth and depth. Light-controlled drug delivery platforms can be generally categorized into three groups: photochemical, photothermal, and photoisomerization-mediated therapies. Various advanced materials, such as metal nanoparticles, metal sulfides and oxides, metal-organic frameworks, carbon nanomaterials, upconversion nanoparticles, semiconductor nanoparticles, stimuli-responsive micelles, polymer- and liposome-based nanoparticles have been applied for light-stimulated drug delivery. In view of the increasing interest in on-demand targeted drug delivery, we review the development of light-responsive systems with a focus on recent advances, key limitations, and future directions.

14.
Pediatr Surg Int ; 36(8): 891-895, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32514720

RESUMO

PURPOSE: Cervicothoracic and apical thoracic neuroblastoma pose unique surgical challenges. We report our experience with the trapdoor anterior thoracotomy (TAT) approach to overcome these difficulties. METHODS: Retrospective review of our centre's neuroblastoma database was conducted. Patients who underwent TAT at our centre were included, their demographic data and clinical reports were analyzed. RESULTS: A total of 21 patients underwent TAT for neuroblastoma, mean age at surgery of 3.5 (0.3-7.9) years, male to female ratio was 11:10. Fifteen patients had cervicothoracic tumors while 6 had apical thoracic tumors. All except 2 were primary tumors. They were stage M (n = 12), MS (n = 1), and L2 (n = 8). At pre-operative assessment, 19 patients had image-defined risk factor (IDRF), including dual compartmental involvement (n = 15), trachea/bronchus compression (n = 4), encasement of carotid (n = 5), subclavian (n = 11), and vertebral arteries (n = 6). Four underwent upfront surgery while 17 received pre-operative chemotherapy of 2-8 (mean 3.9) cycles. All patients accomplished gross total resection. None had MYCN amplification. The postoperative complications included Horner's syndrome (n = 21), Klumpke's palsy (n = 1), winged scapula (n = 1), phrenic nerve palsy (n = 1), and bronchomalacia (n = 2). CONCLUSION: Gross total resection of cervicothoracic and apical thoracic neuroblastoma can be accomplished by TAT with minimal morbidity.


Assuntos
Neuroblastoma/cirurgia , Neoplasias Torácicas/cirurgia , Toracotomia/métodos , Criança , Pré-Escolar , Bases de Dados Factuais , Feminino , Humanos , Lactente , Masculino , Estudos Retrospectivos , Resultado do Tratamento
15.
Anal Biochem ; 566: 40-45, 2019 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-30267709

RESUMO

Amyloid ß (Aß) peptide accumulation in the brain is considered to be one of the hallmarks of Alzheimer's disease. Here, we compare two analytical techniques for detecting neurotoxic Aß1-42 oligomers - Quartz Crystal Microbalance with Dissipation (QCM-D) and Single Molecule Array (Simoa). Both detection methods exploit a feature of the monoclonal antibody bapineuzumab, which targets N-terminal residues 1-5 of Aß with high affinity and use it as both a capture and detection reagent. Assays developed with the two methods allow us to specifically recognize neurotoxic Aß1-42 oligomers and higher aggregates such as fibrils but discriminate against Aß1-42 monomer species. We find that for detection of Aß1-42 oligomers, Simoa was roughly 500 times more sensitive than the QCM-D technique with limits of detection of 0.22 nM and 125 nM, respectively.


Assuntos
Doença de Alzheimer/diagnóstico , Peptídeos beta-Amiloides/análise , Anticorpos Monoclonais Humanizados/química , Fragmentos de Peptídeos/análise , Encéfalo/metabolismo , Diagnóstico Precoce , Ensaio de Imunoadsorção Enzimática , Humanos , Limite de Detecção , Técnicas de Microbalança de Cristal de Quartzo
16.
J Biol Chem ; 291(43): 22661-22670, 2016 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-27609519

RESUMO

Inteins, self-splicing protein elements, interrupt genes and proteins in many microbes, including the human pathogen Mycobacterium tuberculosis Using conserved catalytic nucleophiles at their N- and C-terminal splice junctions, inteins are able to excise out of precursor polypeptides. The splicing of the intein in the mycobacterial recombinase RecA is specifically inhibited by the widely used cancer therapeutic cisplatin, cis-[Pt(NH3)2Cl2], and this compound inhibits mycobacterial growth. Mass spectrometric and crystallographic studies of Pt(II) binding to the RecA intein revealed a complex in which two platinum atoms bind at N- and C-terminal catalytic cysteine residues. Kinetic analyses of NMR spectroscopic data support a two-step binding mechanism in which a Pt(II) first rapidly interacts reversibly at the N terminus followed by a slower, first order irreversible binding event involving both the N and C termini. Notably, the ligands of Pt(II) compounds that are required for chemotherapeutic efficacy and toxicity are no longer bound to the metal atom in the intein adduct. The lack of ammine ligands and need for phosphine represent a springboard for future design of platinum-based compounds targeting inteins. Because the intein splicing mechanism is conserved across a range of pathogenic microbes, developing these drugs could lead to novel, broad range antimicrobial agents.


Assuntos
Anti-Infecciosos/farmacologia , Proteínas de Bactérias/metabolismo , Cisplatino/farmacologia , Mycobacterium tuberculosis/metabolismo , Recombinases Rec A/metabolismo , Proteínas de Bactérias/genética , Humanos , Mycobacterium tuberculosis/genética , Domínios Proteicos , Recombinases Rec A/genética
18.
Small ; 12(20): 2720-30, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27038291

RESUMO

Hepatocyte spheroids microencapsulated in hydrogels can contribute to liver research in various capacities. The conventional approach of microencapsulating spheroids produces a variable number of spheroids per microgel and requires an extra step of spheroid loading into the gel. Here, a microfluidics technology bypassing the step of spheroid loading and controlling the spheroid characteristics is reported. Double-emulsion droplets are used to generate microencapsulated homotypic or heterotypic hepatocyte spheroids (all as single spheroids <200 µm in diameter) with enhanced functions in 4 h. The composition of the microgel is tunable as demonstrated by improved hepatocyte functions during 24 d culture (albumin secretion, urea secretion, and cytochrome P450 activity) when alginate-collagen composite hydrogel is used instead of alginate. Hepatocyte spheroids in alginate-collagen also perform better than hepatocytes cultured in collagen-sandwich configuration. Moreover, hepatocyte functions are significantly enhanced when hepatocytes and endothelial progenitor cells (used as a novel supporting cell source) are co-cultured to form composite spheroids at an optimal ratio of 5:1, which could be further boosted when encapsulated in alginate-collagen. This microencapsulated-spheroid formation technology with high yield, versatility, and uniformity is envisioned to be an enabling technology for liver tissue engineering as well as biomanufacturing.


Assuntos
Hepatócitos/citologia , Alginatos/química , Animais , Colágeno/metabolismo , Ácido Glucurônico/química , Hepatócitos/metabolismo , Ácidos Hexurônicos/química , Hidrogéis/química , Microfluídica/métodos , Ratos , Esferoides Celulares/citologia , Esferoides Celulares/metabolismo , Células-Tronco/citologia , Células-Tronco/metabolismo , Engenharia Tecidual/métodos
19.
Phys Rev Lett ; 116(4): 045301, 2016 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-26871339

RESUMO

A unique feature of ultracold atoms is the separation of length scales, r_{0}≪k_{F}^{-1}, where k_{F} and r_{0} are the Fermi momentum characterizing the average particle distance and the range of interaction between atoms, respectively. For s-wave scattering, Shina Tan discovered that such diluteness leads to universal thermodynamic relations governed by contact. Here, we show that the concept of contact can be generalized to an arbitrary partial-wave scattering. Contact of all partial-wave scatterings forms a contact spectrum, which establishes universal thermodynamic relations with notable differences from those in the presence of s-wave scattering alone. Such a contact spectrum is particularly useful for characterizing many-body correlations in atomic quantum Hall states (QHSs). It has an interesting connection with a special bipartite entanglement spectrum of QHSs and enables an intrinsic probe of atomic QHSs using short-range two-body correlations.

20.
Mol Pharm ; 13(3): 699-709, 2016 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-26808002

RESUMO

Glycyrrhetinic acid (GA), the main hydrolysate of glycyrrhizic acid extracted from the root of licorice, has been used in hepatocellular carcinoma (HCC) therapy. Particularly, GA as a ligand in HCC therapy has been widely explored in different drug delivery systems, including liposomes, micelles, and nanoparticles. There is considerable interest worldwide with respect to the development of GA-modified drug delivery systems due to the extensive presence of GA receptors on the surface of hepatocyte. Up until now, much work has been focused on developing GA-modified drug delivery systems which bear good liver- or hepatocyte-targeted efficiency both in vitro and in vivo. Owing to its contribution in overcoming the limitations of low lipophilicity and poor bioavailability as well as its ability to promote receptor-mediated endocytosis, GA-modified drug delivery systems play an important role in enhancing liver-targeting efficacy and thus are focused on the treatment of HCC. Moreover, since GA-modified delivery systems present more favorable pharmacokinetic properties and hepatocyte-targeting effects, they may be a promising formulation for GA in the treatment of HCC. In this review, we will give an overview of GA-modified novel drug delivery systems, paying attention to their efficacy in treating HCC and discussing their mechanism and the treatment effects.


Assuntos
Antineoplásicos/administração & dosagem , Carcinoma Hepatocelular/tratamento farmacológico , Portadores de Fármacos , Sistemas de Liberação de Medicamentos , Ácido Glicirretínico/administração & dosagem , Neoplasias Hepáticas/tratamento farmacológico , Animais , Antineoplásicos/química , Ácido Glicirretínico/química , Humanos
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