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1.
Anaesthesia ; 76(8): 1060-1067, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33492698

RESUMO

Accidental dural puncture is a recognised complication of labour epidural placement and can cause a debilitating headache. We examined the association between labour epidural case volume and accidental dural puncture rate in specialist anaesthetists and anaesthesia trainees. We performed a retrospective cohort study of labour epidural and combined spinal-epidural nerve blocks performed between 1 July 2013 and 31 December 2017 at Waitemata District Health Board, Auckland, New Zealand. The mean (SD) annual number of obstetric epidural and combined spinal-epidural procedures for high-case volume specialists was 44.2 (15.0), and for low-case volume specialists was 10.0 (6.8), after accounting for caesarean section combined spinal-epidural procedures. Analysis of 7976 labour epidural and combined spinal-epidural procedure records revealed a total of 92 accidental dural punctures (1.2%). The accidental dural puncture rate (95%CI) in high-case volume specialists was 0.6% (0.4-0.9%) and in low-case volume specialists 2.4% (1.4-3.9%), indicating probable skill decay. The odds of accidental dural puncture were 3.77 times higher for low- compared with high-case volume specialists (95%CI 1.72-8.28, p = 0.001). Amongst trainees, novices had a significantly higher accidental dural puncture complication rate (3.1%) compared with registrars (1.2%), OR (95%CI) 0.39 (0.18-0.84), p = 0.016, or fellows (1.1%), 0.35 (0.16-0.76), p = 0.008. Accidental dural puncture complication rates decreased once trainees progressed past the 'novice' training stage.


Assuntos
Analgesia Epidural/efeitos adversos , Analgesia Epidural/estatística & dados numéricos , Analgesia Obstétrica/efeitos adversos , Analgesia Obstétrica/estatística & dados numéricos , Punção Espinal/estatística & dados numéricos , Adulto , Estudos de Coortes , Feminino , Humanos , Trabalho de Parto , Gravidez , Estudos Retrospectivos
2.
Lett Appl Microbiol ; 71(2): 203-209, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32294268

RESUMO

Bacteriophages may be formulated into semi-solid bases for therapeutic delivery. This work investigated the effects of a range of preservatives on the viability of Myoviridae and Siphoviridae bacteriophages when these were formulated into a standard semi-solid cream base. The six preservatives tested included: benzoic acid (0·1%), chlorocresol (0·1%), combination hydroxybenzoates (propyl 4-hydroxybenzoates with methyl 4-hydroxybenzoates) (0·1%), methyl 4-hydroxybenzoate (0·08%), 2-phenoxyethanol (1%) and propyl 4-hydroxybenzoate (0·02%). These were each formulated into cetomacrogol cream aqueous to generate six individual semi-solid bases into which Myoviridae and Siphoviridae bacteriophages were added and tested for stability. Optimal bacteriophage stability was seen when the preservative chlorocresol was used. Bacteriophage in the acidic benzoic acid were the least stable, resulting in complete loss of viability after 4-5 weeks. Of the bacteriophages tested, the Myoviridae KOX1 was significantly more stable than the Siphoviridae PAC1 after 91 days in formulations with each of the preservatives. Our results suggest the need for individual testing of specific bacteriophages in pharmaceutical formulations, as their efficacy when exposed to preservatives and excipients in these delivery forms may vary. SIGNIFICANCE AND IMPACT OF THE STUDY: Bacteriophages are being increasingly investigated as alternatives to antibiotics. While bacteriophages can be formulated in diverse ways for therapeutic delivery, there has been scant work on how excipients and preservatives in these formulations affect stability of different bacteriophages. We demonstrate that the nature of preservatives in formulations will affect bacteriophage stability, and that in these formulations, viability of bacteriophage differs according to their morphology. Our work highlights the need for individual testing of specific bacteriophages in pharmaceutical formulations, as efficacy when exposed to preservatives and excipients in these delivery forms may vary.


Assuntos
Ácido Benzoico/farmacologia , Cresóis/farmacologia , Hidroxibenzoatos/farmacologia , Myoviridae/efeitos dos fármacos , Conservantes Farmacêuticos/farmacologia , Siphoviridae/efeitos dos fármacos , Myoviridae/crescimento & desenvolvimento , Parabenos/farmacologia , Terapia por Fagos/métodos , Siphoviridae/crescimento & desenvolvimento
3.
Phys Rev Lett ; 120(8): 083602, 2018 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-29543019

RESUMO

Quantum networks will enable extraordinary capabilities for communicating and processing quantum information. These networks require a reliable means of storage, retrieval, and manipulation of quantum states at the network nodes. A node receives one or more coherent inputs and sends a conditional output to the next cascaded node in the network through a quantum channel. Here, we demonstrate this basic functionality by using the quantum interference mechanism of electromagnetically induced transparency in a transmon qubit coupled to a superconducting resonator. First, we apply a microwave bias, i.e., drive, to the qubit-cavity system to prepare a Λ-type three-level system of polariton states. Second, we input two interchangeable microwave signals, i.e., a probe tone and a control tone, and observe that transmission of the probe tone is conditional upon the presence of the control tone that switches the state of the device with up to 99.73% transmission extinction. Importantly, our electromagnetically induced transparency scheme uses all dipole allowed transitions. We infer high dark state preparation fidelities of >99.39% and negative group velocities of up to -0.52±0.09 km/s based on our data.

4.
J Am Chem Soc ; 139(25): 8384-8387, 2017 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-28598606

RESUMO

Daily injections of insulin provide lifesaving benefits to millions of diabetics. But currently available prandial insulins are suboptimal: The onset of action is delayed by slow dissociation of the insulin hexamer in the subcutaneous space, and insulin forms amyloid fibrils upon storage in solution. Here we show, through the use of noncanonical amino acid mutagenesis, that replacement of the proline residue at position 28 of the insulin B-chain (ProB28) by (4S)-hydroxyproline (Hzp) yields an active form of insulin that dissociates more rapidly, and fibrillates more slowly, than the wild-type protein. Crystal structures of dimeric and hexameric insulin preparations suggest that a hydrogen bond between the hydroxyl group of Hzp and a backbone amide carbonyl positioned across the dimer interface may be responsible for the altered behavior. The effects of hydroxylation are stereospecific; replacement of ProB28 by (4R)-hydroxyproline (Hyp) causes little change in the rates of fibrillation and hexamer disassociation. These results demonstrate a new approach that fuses the concepts of medicinal chemistry and protein design, and paves the way to further engineering of insulin and other therapeutic proteins.


Assuntos
Hidroxiprolina/química , Insulina/química , Amiloide/química , Cristalografia por Raios X , Dimerização , Hidroxilação , Modelos Biológicos , Modelos Moleculares , Proinsulina/química
5.
J Viral Hepat ; 24(2): 141-147, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27766731

RESUMO

We compared the viral suppressive efficacy of tenofovir disoproxil fumarate (TDF) mono-rescue therapy (TDF group) and TDF plus entecavir (ETV) combination-rescue therapy (TDF + ETV group) in chronic hepatitis B (CHB) patients with lamivudine resistance and entecavir resistance. One hundred and thirty-three CHB patients with lamivudine and entecavir resistance were investigated. Ninety-six patients were treated with TDF and 37 with TDF + ETV for at least 6 months. We compared the virologic response rate (HBV DNA level <20 IU/mL) between the two groups and identified the predictive factors of treatment outcome. There were no significant differences between the two groups in demographic characteristics. Up to 24 months [median: 18 (range 6-24) months], 85.4% and 89.2% of the TDF group and TDF + ETV group, respectively, achieved a virologic response (P=.068). Only the HBV DNA level at baseline was significantly associated with a virologic response in the multivariate analysis. In a subanalysis of patients with HBV DNA levels ≥4 log (IU/mL) at baseline, a higher proportion of patients in the TDF + ETV group than the TDF group achieved a virologic response (92.9% vs 68.3%; P<.001), while 90% of patients with HBV DNA (IU/mL) levels <4 log in all both TDF and TDF + ETV groups achieved a virologic response. TDF mono-rescue therapy is a reasonable option in patients with lamivudine resistance and entecavir resistance. However, the combination strategy should be considered in patients with high baseline HBV DNA levels.


Assuntos
Antivirais/uso terapêutico , Farmacorresistência Viral , Guanina/análogos & derivados , Vírus da Hepatite B/efeitos dos fármacos , Hepatite B Crônica/tratamento farmacológico , Tenofovir/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Antivirais/farmacologia , DNA Viral/sangue , Feminino , Guanina/farmacologia , Guanina/uso terapêutico , Vírus da Hepatite B/isolamento & purificação , Hepatite B Crônica/virologia , Humanos , Lamivudina/farmacologia , Masculino , Pessoa de Meia-Idade , Tenofovir/farmacologia , Resultado do Tratamento , Carga Viral , Adulto Jovem
6.
Dis Esophagus ; 30(12): 1-7, 2017 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-28881891

RESUMO

The utility of induction therapy (IT) in patients with resectable esophageal cancer remains controversial, especially when clinical evidence of nodal metastases is lacking. We sought to compare the survival impact of IT versus upfront surgery (US) in patients with cT3N0 esophageal cancer. We searched the Taiwan Cancer Registry for patients with cT3N0 esophageal cancer who underwent US or IT between 2008 and 2013. Multivariate Cox regression analysis was used to analyze the potential benefits of IT in terms of overall survival (OS) and disease-free survival (DFS). Of the 11752 patients with esophageal cancer included in the nationwide database, 762 (6.5%) had cT3N0 disease. Most cases (720 [94.5%]) had a histological diagnosis of squamous cell carcinoma. Of them, 135 received IT (the IT group) and 237 received surgery first (the US group). In the US group, pretreatment clinical staging was accurate in 47.9% of patients. Twenty-one (8.97%) were clinically overstaged (pT1-2N0), whereas 101 (43.17%) were clinically understaged (pT4N0 or pTanyN1-3). The presence of unexpected nodal metastases was identified in 92.1% of clinically understaged patients. In the IT group, 28 (20.74%) patients did not proceed to surgery after IT. The use of IT was associated with higher R0 resection rates and fewer pathological nodal metastases, despite unexpected M1 disease being more common (all P< 0.05). The 5-year OS rate was significantly higher (42%) in the IT group than in the US group (33%, P= 0.032). Similar findings were observed in terms of 5-year DFS (37% in the IT group versus 29% in the US group, P= 0.009). Multivariate analysis identified US (hazard ratio: 1.42, P= 0.03) and non-R0 resection (hazard ratio: 1.58, P= 0.03) as independent adverse prognostic factors. We found that 43.17% of patients with cT3N0 disease undergoing primary surgery had their disease understaged. The use of IT before esophagectomy significantly improves OS and DFS in patients with clinical T3N0 esophageal squamous cell carcinoma.


Assuntos
Carcinoma de Células Escamosas/secundário , Carcinoma de Células Escamosas/terapia , Neoplasias Esofágicas/patologia , Neoplasias Esofágicas/terapia , Quimioterapia de Indução , Idoso , Quimiorradioterapia Adjuvante , Quimioterapia Adjuvante , Intervalo Livre de Doença , Esofagectomia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Terapia Neoadjuvante , Estadiamento de Neoplasias , Neoplasia Residual , Estudos Retrospectivos , Taxa de Sobrevida , Taiwan
7.
Environ Monit Assess ; 187(2): 27, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25632908

RESUMO

The multi-year characteristics of ambient volatile organic compounds (VOCs) and their source contribution in a selected metropolitan (Seoul) and rural (Seokmolee) areas in Korea were investigated to provide the framework for development and implementation of ambient VOC control strategies. For Seoul, none of the three VOC groups exhibited any significant trend in their ambient concentrations, whereas for Seokmolee, they all showed a generally decreasing trend between 2005 and 2008 and an increasing trend after 2008. Two paraffinic (ethane and propane) and two olefin (ethylene and propylene) hydrocarbons displayed higher concentrations during the cold season than warm season, while the other target VOCs did not exhibit any significant trends. Ethylene and toluene were the first and second largest contributors to ozone formation, respectively, whereas several other VOCs displayed photochemical ozone formation potential values less than 0.01 ppb. For both areas, there was a significant negative correlation between ambient temperature and the selected VOC group concentrations. In contrast, a significant positive correlation was observed between relative humidity and the three VOC group concentrations, while no significant correlation was observed between wind speed and VOC group concentrations. For Seoul, the combination of vehicle exhaust and gasoline/solvent evaporation was the greatest source of VOCs, followed by liquid natural gas (LNG) and liquid petroleum gas (LPG). However, combination of LNG and LPG was the greatest source of VOCs at Seokmolee, followed by the combination of vehicle exhaust and gasoline evaporation, and then biogenic sources.


Assuntos
Poluentes Atmosféricos/análise , Monitoramento Ambiental , Ozônio/análise , Compostos Orgânicos Voláteis/análise , Hidrocarbonetos/análise , Meteorologia , República da Coreia , Estações do Ano , Tolueno , Emissões de Veículos/análise
8.
J Appl Microbiol ; 117(3): 834-45, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24925305

RESUMO

AIMS: The aim of this study was to evaluate the effects of Bifidobacterium lactis HY8101 on insulin resistance induced using tumour necrosis factor-α (TNF-α) in rat L6 skeletal muscle cells and on the KK-A(Y) mouse noninsulin-dependent diabetes mellitus (NIDDM) model. METHODS AND RESULTS: The treatment using HY8101 improved the insulin-stimulated glucose uptake and translocation of GLUT4 via the insulin signalling pathways AKT and IRS-1(Tyr) in TNF-α-treated L6 cells. HY8101 increased the mRNA levels of GLUT4 and several insulin sensitivity-related genes (PPAR-γ) in TNF-α-treated L6 cells. In KK-A(Y) mice, HY8101 decreased fasting insulin and blood glucose and significantly improved insulin tolerance. HY8101 improved diabetes-induced plasma total cholesterol and triglyceride (TG) levels and increased the muscle glycogen content. We observed concurrent transcriptional changes in the skeletal muscle tissue and the liver. In the skeletal muscle tissue, the glycogen synthesis-related gene pp-1 and GLUT4 were up-regulated in mice receiving HY8101 treatment. In the liver, the hepatic gluconeogenesis-regulated genes (PCK1 and G6PC) were down-regulated in mice receiving HY8101 treatment. CONCLUSIONS: Bifidobacterium lactis HY8101 can be used to moderate glucose metabolism, lipid metabolism and insulin sensitivity in mice and in cells. SIGNIFICANCE AND IMPACT OF THE STUDY: Bifidobacterium lactis HY8101 might have potential as a probiotic candidate for alleviating metabolic syndromes such as diabetes.


Assuntos
Bifidobacterium , Diabetes Mellitus Tipo 2/terapia , Resistência à Insulina , Probióticos/uso terapêutico , Animais , Glicemia/análise , Linhagem Celular , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/metabolismo , Glucose/metabolismo , Transportador de Glucose Tipo 4/metabolismo , Glicogênio/metabolismo , Insulina/farmacologia , Proteínas Substratos do Receptor de Insulina/metabolismo , Fígado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Músculo Esquelético/metabolismo , Ratos , Transdução de Sinais , Fator de Necrose Tumoral alfa/farmacologia
9.
Phys Rev Lett ; 109(5): 050507, 2012 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-23006158

RESUMO

We demonstrate initialization by joint measurement of two transmon qubits in 3D circuit quantum electrodynamics. Homodyne detection of cavity transmission is enhanced by Josephson parametric amplification to discriminate the two-qubit ground state from single-qubit excitations nondestructively and with 98.1% fidelity. Measurement and postselection of a steady-state mixture with 4.7% residual excitation per qubit achieve 98.8% fidelity to the ground state, thus outperforming passive initialization.

10.
Phys Rev Lett ; 106(22): 220502, 2011 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-21702586

RESUMO

We perform state tomography of an itinerant squeezed state of the microwave field prepared by a Josephson parametric amplifier (JPA). We use a second JPA as a preamplifier to improve the quantum efficiency of the field quadrature measurement from 2% to 36%±4%. Without correcting for the detection inefficiency we observe a minimum quadrature variance which is 68(-7)(+9)% of the variance of the vacuum. We reconstruct the state's density matrix by a maximum likelihood method and infer that the squeezed state has a minimum variance less than 40% of the vacuum, with uncertainty mostly caused by calibration systematics.

11.
Opt Lett ; 35(9): 1398-400, 2010 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-20436582

RESUMO

This study investigates a spatially band-tunable color-cone lasing emission (CCLE) based on a dye-doped cholesteric liquid crystal with a photoisomerizable chiral dopant (IBM). Experimental results show that the lasing band of the formed CCLE of the cell with a photoinduced pitch gradient can be spatially tuned among various color regions by adjusting the pumped position of the cell. The spatially band tunability of the laser results from the UV-irradiation-induced decrease of the helical twisting power of IBM via trans-->cis isomerization, accordingly shrinking the pitch of the cholesteric-liquid-crystal host. The total spatially tunable wavelength range for the laser exceeds 100 nm.

12.
Value Health ; 17(7): A424, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27201084
13.
Plant Dis ; 93(2): 196, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30764119

RESUMO

Pineapple (Ananas comosus) is one of the major fruit crops in Taiwan, accounting for 275 million U.S. dollars in 2006, following betel nut and citrus production in crop value. Tainung No. 17 is the most important cultivar, accounting for more than 70% of pineapples planted. Mealybug wilt of pineapple (MWP) is one of the most destructive diseases of pineapple. Pineapple mealybug wilt-associated virus-1 (PMWaV-1), PMWaV-2, and PMWaV-3 were identified as three distinct species in Ampelovirus from diseased Hawaiian pineapple (1,2). In November of 2007, pineapples (cv. Tainung No. 17) planted in Pingtung County of southern Taiwan showed symptoms similar to MWP. Mealybugs (Dysmicoccus brevipes) were also found. Three primer pairs, 225/226, 223/224, and 263/264 described previously specific for the HSP70h genes of PMWaV-1 (1), -2, and -3 (2), respectively, were used to detect the presence of these three viruses by reverse transcription (RT)-PCR. Expected DNA fragments of 590, 610, and 499 nt were obtained from the total RNA isolated from the leaves of diseased pineapples with primer pairs 225/226, 223/224, and 263/264, respectively. The RT-PCR amplified fragments were cloned, sequenced, and analyzed. The 590-nt fragment (Accession No. EU769113) shared 91.6 to 99.5% nucleotide and 96.8 to 99.5% amino acid identity to those of five isolates of PMWaV-1 available in the GenBank; one each from Hawaii (Accession No. AF414119) and Thailand (Accession No. EF620774) and three from Australia (Accession Nos. EF488752, EF467923, and EF467925). The 610-nt fragment (Accession No. EU769115) showed 98.7 and 99.7% nucleotide and 98% and 100% amino acid identity to those of PMWaV-2 from Hawaii (Accession No. AF283103) and Thailand (Accession No. EU016675), respectively. The 499-nt fragment (Accession No. FJ209047) shared 86.8 to 99.0% nucleotide and 94.0 to 100.0% amino acid identity to those of five PMWaV-3 isolates available in the GenBank; one from Hawaii (Accession No. DQ399259) and four from Australia (Accession Nos. EF467918, EF467919, EF488754, and EF488755). Using primer pairs FJ08-1 (5'-ATGGCTGATTCGAGC)/FJ08-2 (5'-TTATTTGCGTCCACC), FJ08-7 (5'-AGTGAGATTGATCGT)/FJ08-8 (5'-TGCAGGTATCCGCTG), and FJ08-35 (5'-AACGACCGAACTCGC)/FJ08-36 (5'-ATACTACAGATATTG) specific to the coat protein (CP) genes of PMWaV-1, -2, and -3, respectively, expected DNA fragments of 774, 909, and 789 nt were amplified by RT-PCR. The 774-nt CP gene of PMWaV-1 (Accession No. EU769114) shared 99% nucleotide and 98.4% amino acid identity to those of Hawaiian isolate (Accession No. AF414119). The 909-nt CP gene of PMWaV-2 (Accession No. EU769116) shared 99.0 and 99.1% nucleotide identity with isolates from Hawaii (Accession No. AF283103) and Cuba (Accession No. DQ225114), respectively, and 99.3% amino acid identity with both. The 789-nt CP gene of PMWaV-3 (Accession No. FJ209048) shared 99.1% nucleotide and 98.1% amino acid identity to those of the Hawaiian isolate (Accession No. DQ399259). One to two viruses among PMWaV-1, -2, and -3 were detected in all 40 samples collected from diseased pineapples. To our knowledge, this is the first report to identify three PMWaVs in the most important and widely planted pineapple cultivar in Taiwan, Tainung No. 17, by molecular characterization of the HSP70h and CP genes. References: (1) D. M. Sether et al. Plant Dis. 85:856, 2001. (2) D. M. Sether et al. Plant Dis. 89:450, 2005.

14.
Transplant Proc ; 39(10): 3444-5, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18089402

RESUMO

We isolated mesenchymal stem cells (MSCs) from adult human bone marrow. By using reverse-transcription polymerase chain reactions, we confirmed that MSCs possessed the potential to differentiate into hepatocyte-like cells (MSC-HLCs) with the expression of hepatocyte-specific marker genes. We further observed that fibronectin (FN) treatment significantly inhibited lipopolysaccharide (LPS)-induced apoptotic activities in FN-treated MSC-HLCs, as detected by caspase 3 enzyme-linked immunosorbent (ELISA) and terminal dUTP nick-end labeling (TUNEL) assays (P<.05). The FN-treated MSC-HLCs were transplanted into SCID mice with or without LPS injection. This study demonstrated that FN treatment improved liver function repair and survival rates among LPS-treated SCID mice.


Assuntos
Fibronectinas/farmacologia , Hepatócitos/citologia , Lipopolissacarídeos/antagonistas & inibidores , Lipopolissacarídeos/farmacologia , Transplante de Células-Tronco Mesenquimais/métodos , Células-Tronco Mesenquimais/citologia , Animais , Apoptose/efeitos dos fármacos , Caspase 3/análise , Diferenciação Celular , Sobrevivência Celular/efeitos dos fármacos , Ensaio de Imunoadsorção Enzimática , Humanos , Marcação In Situ das Extremidades Cortadas , Testes de Função Hepática , Camundongos , Camundongos SCID , Transplante Heterólogo
15.
Transplant Proc ; 38(9): 3086-7, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17112905

RESUMO

We report that human dermis-derived mesenchymal stem cells (hDMSCs) possess differentiation potential of epidermis facilitating wound healing in skin-defect nude mice in combination with the treatment using gelatin/thermosensitive poly N-isopropylacrylamide (pNIPAAm)/polypropylene (PP). The results showed that the rate of cell growth and wound recovery in the hDMSC and gelatin/pNIPAAm/PP-treated group was significantly greater than those in the gelatin/pNIPAAm/PP-treated only group (P < .01). The reepithelialization marker of human pan-cytokeratin was also significantly increased on days 14 and day 21 in the wound site of hDMSCs and gelatin/pNIPAAm/PP-treated group. Furthermore, the stem cell marker of human CD13 gradually decreased during the period of wound healing. In sum, this novel method provided a transferring system for stem cell therapy, maintaining its temperature-sensitive property of easy peeling by lower temperature treatment.


Assuntos
Transplante de Células-Tronco Mesenquimais , Pele/patologia , Cicatrização/fisiologia , Animais , Derme/citologia , Modelos Animais de Doenças , Humanos , Camundongos , Camundongos Nus , Transplante Heterólogo
16.
Transplant Proc ; 38(5): 1616-7, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16797368

RESUMO

Gelatin scaffolds for ex vivo cell cultures are a promising development. These scaffolds can be used as three-dimensional skeletons for cell attachment and culture before transplantation. In this study, we isolated and cultivated neural stem cells from human brain tissues in serum-free medium (DMEM+F12 nutrient). Better neuron growth was observed using the tetrazolium assay (MTT) in the group when basic fibroblast growth factor (bFGF) was coated on the gelatin polymer scaffold. Further development of this nontoxic system may help the future development of transplantation of human neural stem cells.


Assuntos
Transplante de Células , Fatores de Crescimento de Fibroblastos/fisiologia , Gelatina , Sistema Nervoso/citologia , Células-Tronco/citologia , Transplante de Células/métodos , Epilepsia/terapia , Humanos
17.
Appl Phys Lett ; 1082016.
Artigo em Inglês | MEDLINE | ID: mdl-27114615

RESUMO

We have fabricated a wide-bandwidth, high dynamic range, low-noise cryogenic amplifier based on a superconducting kinetic inductance traveling-wave device. The device was made from NbTiN and consisted of a long, coplanar waveguide on a silicon chip. By adding a DC current and an RF pump tone we are able to generate parametric amplification using three-wave mixing. The devices exhibit gain of more than 15 dB across an instantaneous bandwidth from 4 to 8 GHz. The total usable gain bandwidth, including both sides of the signal-idler gain region, is more than 6 GHz. The noise referred to the input of the devices approaches the quantum limit, with less than 1 photon excess noise. Compared to similarly constructed four-wave mixing amplifiers, these devices operate with the RF pump at ~20 dB lower power and at frequencies far from the signal. This will permit easier integration into large scale qubit and detector applications.

18.
J Vis Exp ; (112)2016 06 10.
Artigo em Inglês | MEDLINE | ID: mdl-27340914

RESUMO

Stem and progenitor cells from the adult pancreas could be a potential source of therapeutic beta-like cells for treating patients with type 1 diabetes. However, it is still unknown whether stem and progenitor cells exist in the adult pancreas. Research strategies using cre-lox lineage-tracing in adult mice have yielded results that either support or refute the idea that beta cells can be generated from the ducts, the presumed location where adult pancreatic progenitors may reside. These in vivo cre-lox lineage-tracing methods, however, cannot answer the questions of self-renewal and multi-lineage differentiation-two criteria necessary to define a stem cell. To begin addressing this technical gap, we devised 3-dimensional colony assays for pancreatic progenitors. Soon after our initial publication, other laboratories independently developed a similar, but not identical, method called the organoid assay. Compared to the organoid assay, our method employs methylcellulose, which forms viscous solutions that allow the inclusion of extracellular matrix proteins at low concentrations. The methylcellulose-containing assays permit easier detection and analyses of progenitor cells at the single-cell level, which are critical when progenitors constitute a small sub-population, as is the case for many adult organ stem cells. Together, results from several laboratories demonstrate in vitro self-renewal and multi-lineage differentiation of pancreatic progenitor-like cells from mice. The current protocols describe two methylcellulose-based colony assays to characterize mouse pancreatic progenitors; one contains a commercial preparation of murine extracellular matrix proteins and the other an artificial extracellular matrix protein known as a laminin hydrogel. The techniques shown here are 1) dissociation of the pancreas and sorting of CD133(+)Sox9/EGFP(+) ductal cells from adult mice, 2) single cell manipulation of the sorted cells, 3) single colony analyses using microfluidic qRT-PCR and whole-mount immunostaining, and 4) dissociation of primary colonies into single-cell suspensions and re-plating into secondary colony assays to assess self-renewal or differentiation.


Assuntos
Pâncreas , Células-Tronco , Envelhecimento , Animais , Diferenciação Celular , Células Secretoras de Insulina , Camundongos
19.
Cancer Genomics Proteomics ; 13(6): 437-442, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27807066

RESUMO

BACKGROUND: Previous work characterized variants of the EL4 murine lymphoma cell line. Some are non-metastatic, and others metastatic, in syngenic mice. In addition, metastatic EL4 cells were stably transfected with phospholipase D2 (PLD2), which further enhanced metastasis. MATERIALS AND METHODS: Microarray analyses of mRNA expression was performed for non-metastatic, metastatic, and PLD2-expressing metastatic EL4 cells. RESULTS: Many differences were observed between non-metastatic and metastatic cell lines. One of the most striking new findings was up-regulation of mRNA for the matricellular protein WNT1-inducible signaling pathway protein 1 (CCN4) in metastatic cells; increased protein expression was verified by immunoblotting and immunocytochemistry. Other differentially expressed genes included those for reproductive homeobox 5 (Rhox5; increased in metastatic) and cystatin 7 (Cst7; decreased in metastatic). Differences between PLD2-expressing and parental cell lines were limited but included the signaling proteins Ras guanyl releasing protein 1 (RGS18; increased with PLD2) and suppressor of cytokine signaling 2 (SOCS2; decreased with PLD2). CONCLUSION: The results provide insights into signaling pathways potentially involved in conferring metastatic ability on lymphoma cells.


Assuntos
Proteínas de Sinalização Intercelular CCN/biossíntese , Regulação Neoplásica da Expressão Gênica/genética , Linfoma/genética , Análise em Microsséries , Proteínas Proto-Oncogênicas/biossíntese , Animais , Proteínas de Sinalização Intercelular CCN/genética , Linhagem Celular Tumoral , Cistatinas/biossíntese , Cistatinas/genética , Modelos Animais de Doenças , Proteínas de Homeodomínio/biossíntese , Proteínas de Homeodomínio/genética , Humanos , Linfoma/patologia , Camundongos , Metástase Neoplásica , Fosfolipase D/biossíntese , Fosfolipase D/genética , Proteínas Proto-Oncogênicas/genética , RNA Mensageiro/biossíntese , Transdução de Sinais/genética , Proteínas Supressoras da Sinalização de Citocina/biossíntese , Proteínas Supressoras da Sinalização de Citocina/genética , Fatores de Transcrição/biossíntese , Fatores de Transcrição/genética
20.
Stem Cell Res ; 16(1): 40-53, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26691820

RESUMO

Progenitor cells in the adult pancreas are potential sources of endocrine beta cells for treating type 1 diabetes. Previously, we identified tri-potent progenitor cells in the adult (2-4month-old) murine pancreas that were capable of self-renewal and differentiation into duct, acinar, and endocrine cells in vitro. These progenitor cells were named pancreatic colony-forming units (PCFUs). However, because PCFUs are a minor population in the pancreas (~1%) they are difficult to study. To enrich PCFUs, strategies using cell-surface marker analyses and fluorescence-activated cell sorting were developed. We found that CD133(high)CD71(low) cells, but not other cell populations, enriched PCFUs by up to 30 fold compared to the unsorted cells. CD133(high)CD71(low) cells generated primary, secondary, and subsequent colonies when serially re-plated in Matrigel-containing cultures, suggesting self-renewal abilities. In the presence of a laminin hydrogel, CD133(high)CD71(low) cells gave rise to colonies that contained duct, acinar, and Insulin(+)Glucagon(+) double-hormonal endocrine cells. Colonies from the laminin hydrogel culture were implanted into diabetic mice, and five weeks later duct, acinar, and Insulin(+)Glucagon(-) cells were detected in the grafts, demonstrating tri-lineage differentiation potential of CD133(high)CD71(low) cells. These CD133(high)CD71(low) cells will enable future studies of putative adult pancreas stem cells in vivo.


Assuntos
Antígeno AC133 , Envelhecimento/fisiologia , Antígenos CD/metabolismo , Membrana Celular/metabolismo , Ensaio de Unidades Formadoras de Colônias , Células-Tronco Multipotentes/citologia , Pâncreas/citologia , Receptores da Transferrina/metabolismo , Células Acinares/citologia , Animais , Autorrenovação Celular , Glucagon/metabolismo , Imuno-Histoquímica , Insulina/metabolismo , Camundongos Endogâmicos C57BL , Células-Tronco Multipotentes/metabolismo , Células-Tronco Multipotentes/ultraestrutura , Ductos Pancreáticos/citologia , Inclusão em Parafina , Análise de Sequência de RNA , Fixação de Tecidos
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