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1.
Opt Lett ; 49(12): 3364-3367, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38875621

RESUMO

High-performance atomic magnetometers (AMs) rely on the measurement of optical rotation, which requires a set of bulky polarization optics that limit their applications in scenarios where portability and compactness are necessary. In this study, a miniaturized AM is constructed based on a cubic 87Rb vapor cell and monolithic metalens, which provides an integrated scheme to achieve optical rotation detection induced by the circular birefringence of polarized atoms. The designed metalens achieves polarization splitting with deflection angles of ±10∘ and focusing with efficiencies of approximately 30% for orthogonal linear polarizations. The sensitivity of our compact device is ∼30 fT/Hz1/2 with a dynamic range of around ±1.45 nT. We envision that the presented approach paves the way for the chip integration of emerging atomic devices, which are in demand for applications such as biomagnetic imaging and portable atomic gyroscopes.

2.
Dig Dis ; 41(3): 506-512, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36288720

RESUMO

BACKGROUND: With the increasing incidence of upper digestive tract tumors, more upper digestive tract surgeries are performed each year, and surgeons have difficulty in the postoperative management of gastrointestinal anastomotic fistula. The use of a new minimally invasive technique, endoluminal vacuum-assisted closure (E-VAC), has increased the success rate of the treatment of gastrointestinal fistula. METHODS: We present 6 cases of gastrointestinal fistula treated in our hospital in 2021: 3 cases of anastomotic fistula after esophageal cancer surgery, 2 cases of anastomotic fistula after gastric cancer surgery, and one case of esophageal rupture after trauma. With E-VAC and other adjuvant treatment measures, the gastrointestinal fistulas were eventually closed or significantly reduced. RESULTS: Both local and systemic infections in all 6 patients were controlled with the use of E-VAC device, resulting in significant reduction or closure of fistulas. CONCLUSION: E-VAC devices can effectively help in the removal of the exudate and necrotic tissue around the fistula, promote the proliferation of granulation tissue, and support closure of the fistula. However, further improvements to the device are needed to improve patient comfort and operational safety.


Assuntos
Fístula , Tratamento de Ferimentos com Pressão Negativa , Trato Gastrointestinal Superior , Humanos , Tratamento de Ferimentos com Pressão Negativa/efeitos adversos , Tratamento de Ferimentos com Pressão Negativa/métodos , Estômago , Anastomose Cirúrgica/efeitos adversos , Fístula/etiologia , Fístula/cirurgia , Fístula Anastomótica/etiologia , Fístula Anastomótica/terapia
3.
Proc Natl Acad Sci U S A ; 116(6): 2068-2077, 2019 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-30674679

RESUMO

Nectin-like (Necl) molecules are Ca2+-independent Ig-like transmembrane cell adhesion molecules that participate in junctions between different cell types. The specific cell-cell adhesions mediated by Necl proteins are important in neural development and have been implicated in neurodegenerative diseases. Here, we present the crystal structure of the mouse Necl-4 full ectodomain and the structure of the heterophilic Necl ectodomain complex formed by the mNecl-4 and mNecl-1 ectodomains. We demonstrate that, while the ectodomain of mNecl-4 is monomeric, it forms a stable heterodimer with Ig1 of mNecl-1, with an affinity significantly higher than that observed for self-dimerization of the mNecl-1 ectodomain. We validated our structural characterizations by performing a surface plasmon resonance assay and an Fc fusion protein binding assay in mouse primary dorsal root ganglia neurites and Schwann cells and identified a selection of residues important for heterophilic interactions. Finally, we proposed a model of Necl binding specificity that involves an induced-fit conformational change at the dimerization interface.


Assuntos
Moléculas de Adesão Celular/química , Moléculas de Adesão Celular/metabolismo , Imunoglobulinas/química , Imunoglobulinas/metabolismo , Sequência de Aminoácidos , Animais , Sítios de Ligação , Moléculas de Adesão Celular/genética , Imunoglobulinas/genética , Camundongos , Camundongos Knockout , Modelos Moleculares , Ligação Proteica , Conformação Proteica , Domínios e Motivos de Interação entre Proteínas , Multimerização Proteica , Proteínas Recombinantes de Fusão , Relação Estrutura-Atividade
5.
Transgenic Res ; 25(6): 829-837, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27696149

RESUMO

Asthma is a common chronic inflammatory disease in the airways with wide prevalence, and it is thought to be caused by the combinational factors in environment and genetics. A large body of studies has suggested that cell immunity played a vital role in regulating the airway hyperreactivity (AHR) and inflammation. Therefore, we here developed a mouse model of asthma by microinjecting the pronucleus with a vector spontaneously coding human IL10 and TGFB1 gene to explore the possible interaction between these two potent molecules during asthma progression. From the total 35 newborn mice, we successfully obtained 3 founders expressing exogenous genes. In the transgenic mice, we observed profoundly enhanced expression of IL10 and TGFB1. In the condition of ovalbumin challenge, transgenic mice displayed a 1.9-fold higher MCh50 score than wild-type counterparts, indicating reminiscent AHR. Meanwhile, a three-fold decrease of cell counts in bronchoalveolar lavage fluid (BALF) was recorded as well. These results suggested that IL10 and TGFB1 cooperatively protected the respiratory system in response to antigenic stimulus. To interrogate the respective behaviors of the two genes, we quantified the expression of downstream genes in IL10 signaling or TGFB1 signaling. We observed that the examined genes in IL10 signaling were significantly repressed, especially IL5, which showed 5.4-fold decreased expression. Most genes were not altered in TGFB1 signaling, and the production of endogenous TGFB1 was significantly inhibited. These evidences collectively proved that the activation of IL0 and TGFB1 protected the host from antigen-induced asthma, possibly through IL10 signaling. This study shed some light on the modulations of IL10 and TGFB1, and related networks to asthma progression.


Assuntos
Asma/genética , Inflamação/genética , Interleucina-10/genética , Fator de Crescimento Transformador beta1/genética , Animais , Asma/induzido quimicamente , Asma/patologia , Líquido da Lavagem Broncoalveolar , Modelos Animais de Doenças , Resistência à Doença/genética , Regulação da Expressão Gênica , Humanos , Inflamação/patologia , Pulmão/metabolismo , Pulmão/patologia , Camundongos , Camundongos Transgênicos/genética , Ovalbumina/toxicidade , Transdução de Sinais
6.
Pacing Clin Electrophysiol ; 39(12): 1351-1358, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27723101

RESUMO

BACKGROUND: The mechanisms underlying atrial fibrillation (AF) initiation and pulmonary vein isolation (PVI) effectiveness remain unclear. Ganglionated plexus (GPs) have been implicated in AF initiation and maintenance. In this study, we evaluated the impact of GP ablation in patients with pulmonary vein (PV) firing after PVI. METHODS: Patients with drug-refractory paroxysmal AF undergoing radiofrequency catheter ablation therapy with PVI were screened. Among 840 cases over a 3.75-year period, 12 cases were identified with persistent PV firing (left = 4 and right = 8) after PVI was achieved and left atrial sinus rhythm restored. Adjacent GP ablation was performed anatomically and followed if necessary by additional PV ablation. RESULTS: In eight patients, PV firing was terminated during GP ablation outside of the circumferential ablation line. In one patient, additional PV ablation resulted in cessation of PV firing and in the remaining three patients, firing could not be terminated by GP ablation or additional PVI. CONCLUSION: GP ablation outside of wide antral circumferential line frequently results in the cessation of rapid firing from electrically isolated PVs. These observations suggest that interactions between left atrium and PV beyond electrical conduction warrant consideration in AF mechanisms.


Assuntos
Fibrilação Atrial/cirurgia , Ablação por Cateter/métodos , Gânglios Autônomos/cirurgia , Sistema de Condução Cardíaco/cirurgia , Veias Pulmonares/cirurgia , Cirurgia Assistida por Computador/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Pontos de Referência Anatômicos/diagnóstico por imagem , Fibrilação Atrial/diagnóstico por imagem , Mapeamento Potencial de Superfície Corporal/métodos , Feminino , Gânglios Autônomos/diagnóstico por imagem , Sistema de Condução Cardíaco/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Veias Pulmonares/diagnóstico por imagem , Resultado do Tratamento
7.
Inflamm Res ; 62(4): 387-97, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23334076

RESUMO

OBJECTIVE: Apoptosis of alveolar epithelial cells (AECs) plays a key role in acute lung injury (ALI). Understanding the underlying mechanism is conducive to the treatment of ALI. The goal of this study was to determine the possible involvement of nuclear factor-κB (NF-κB)/p65 and Bax/Bcl-2 in tumor necrosis factor-α (TNF-α)-induced apoptosis in AECs. METHODS: Type II AECs, A549, with or without NF-κB/p65 expression silenced by small interfering RNA (siRNA) were challenged with TNF-α. The levels of NF-κB/p65, Bcl-2 and Bax were detected by reverse transcription-polymerase chain reaction, Western blotting, and immunocytochemical staining. The apoptosis rate was measured by flow cytometry. RESULTS: TNF-α challenge significantly increased the transcription and translation of NF-κB/p65 and Bax genes, but significantly decreased the Bcl-2 gene level. siRNA silencing of NF-κB/p65 reversed the effect of TNF-α on NF-κB/p65, Bcl-2 and Bax, and significantly decreased the TNF-α-induced apoptosis rate of AECs, as compared to the non-silenced cells. CONCLUSIONS: This study indicates that NF-κB plays an important role in the process of TNF-α-induced apoptosis in AECs, via regulation of the expression of Bcl-2 and Bax.


Assuntos
Células Epiteliais/metabolismo , NF-kappa B/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteína X Associada a bcl-2/metabolismo , Apoptose/fisiologia , Linhagem Celular Tumoral , Humanos , NF-kappa B/genética , Alvéolos Pulmonares/citologia , Interferência de RNA , Fator de Necrose Tumoral alfa/farmacologia
8.
Biosensors (Basel) ; 12(12)2022 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-36551063

RESUMO

Recent years have seen rapid development of chip-scale atomic devices due to their great potential in the field of biomedical imaging, namely chip-scale atomic magnetometers that enable high resolution magnetocardiography (MCG) and magnetoencephalography (MEG). For atomic devices of this kind, vertical cavity surface emitting lasers (VCSELs) have become the most crucial components as integrated pumping sources, which are attracting growing interest. In this paper, the application of VCSELs in chip-scale atomic devices are reviewed, where VCSELs are integrated in various atomic bio-sensing devices with different operating environments. Secondly, the mode and polarization control of VCSELs in the specific applications are reviewed with their pros and cons discussed. In addition, various packaging of VCSEL based on different atomic devices in pursuit of miniaturization and precision measurement are reviewed and discussed. Finally, the VCSEL-based chip-scale atomic magnetometers utilized for cardiac and brain magnetometry are reviewed in detail. Nowadays, biosensors with chip integration, low power consumption, and high sensitivity are undergoing rapid industrialization, due to the growing market of medical instrumentation and portable health monitoring. It is promising that VCSEL-integrated chip-scale atomic biosensors as featured applications of this kind may experience extensive development in the near future.


Assuntos
Técnicas Biossensoriais , Lasers , Desenho de Equipamento , Encéfalo
9.
Magn Reson Imaging ; 84: 115-123, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34619291

RESUMO

OBJECTIVES: Liver vessel density can be evaluated by DDVD (diffusion derived vessel density): DDVD(b0b1) = Sb0/ROIarea0 - Sb1/ROIarea1, where Sb0 and Sb1 refer to the liver signal when b is 0 or 1 s/mm2. Sb1 and ROIarea1 may be replaced by other b-values. With a rat biliary duct ligation (BDL) model, this study assesses the usefulness of liver DDVD computed from a simplified IVIM imaging protocol using b = 25 and b = 50 to replace b = 1 s/mm2, alone and in combination with other IVIM parameters. METHODS: Male Sprague-Dawley rats were used. The rat number was 5, 5, 5, and 3 respectively, for the timepoints of 7, 14, 21, 28 days post-BDL surgery. 12 rats had partial biliary duct recanalization performed after the rats had BDL for 7 days and then again followed-up for a mean of 14 days. Liver diffusion MRIs were acquired at 3.0 T with a b-value distribution of 0, 25, 50, 75, 100, 150, 300, 700, 1000 s/mm2. DDVDmean (control rats n = 6) was the mean of DDVD(b0b25) and DDVD(b0b50). IVIM fitting started from b = 0 s/mm2 with segmented fitting and a threshold b of 50 s/mm2 (n = 5 for control rats). Three 3-D spaces were constructed using a combination of the four diffusion parameters. RESULTS: The control rats and BDL rats (n = 18) had a liver DDVDmean of 84.0 ± 26.2 and 44.7 ± 14.4 au/pixel (p < 0.001). All 3-D spaces totally separated healthy livers and all fibrotic livers (n = 30, BDL rats and recanalization rats). The mean relative distance between healthy liver cluster and fibrotic liver cluster was 0.331 for PF, Dslow, and Dfast; 0.381 for PF, Dfast, and DDVDmean; and 0.384 for PF, Dslow, and DDVDmean. CONCLUSION: A combination of PF, Dslow, and Dfast allows total separation of healthy livers and fibrotic livers and the integration of DDVD improved the separation.


Assuntos
Imagem de Difusão por Ressonância Magnética , Fígado , Animais , Imagem de Difusão por Ressonância Magnética/métodos , Fígado/diagnóstico por imagem , Fígado/patologia , Cirrose Hepática/diagnóstico por imagem , Cirrose Hepática/patologia , Masculino , Movimento (Física) , Ratos , Ratos Sprague-Dawley , Reprodutibilidade dos Testes
10.
Oncol Lett ; 19(1): 805-812, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31897197

RESUMO

Gastric cancer (GC) is one of the major diseases that threaten human health. Although the development of novel drugs has significantly improved the efficacy of GC chemotherapy, the 5-year survival rate of patients with GC remains unsatisfactory. In the present study, the role and mechanism of the long non-coding RNA (lncRNA) metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) in GC proliferation was investigated. Clinical specimens and cancer cells were analyzed by western blotting or immunofluorescence. Reverse transcription-quantitative polymerase chain reaction analysis of 57 paired GC and non-tumorous tissues revealed elevated expression of MALAT1 in GC tissues compared with controls. In addition, increased MALAT1 was associated with elevated levels of microtubule-associated protein 1 light chain 3ß (LC3B) and antigen Ki67, which are autophagy and proliferation markers, respectively. MTT and colony formation assay results demonstrated that MALAT1 promoted GC cell proliferation. To the best of our knowledge, the present study was the first to demonstrate that upregulated MALAT1 was associated with increased autophagy activation in GC tissues. Furthermore, this study reported that MALAT1 increased cell proliferation and enhanced autophagy activation in GC cells. In addition, the results revealed that MALAT1 inhibited microRNA (miR)-204 expression in GC cells. The present study also demonstrated that miR-204 repressed autophagy through the downregulation of LC3B and transient receptor potential melastatin 3 expression in GC cells. These results indicated that MALAT1 activated autophagy and promoted cell proliferation by downregulating miR-204 expression in GC.

12.
Zhejiang Da Xue Xue Bao Yi Xue Ban ; 37(1): 39-44, 2008 01.
Artigo em Chinês | MEDLINE | ID: mdl-18275118

RESUMO

OBJECTIVE: To explore the effects of 50 Hz sinusoidal magnetic fields (MF) on secretion function of primary human villous trophoblasts in vitro, and the interference effect of "noise" MF. METHODS: The trophoblasts were isolated from human villus by trypsin digestion and incubated in DMEM medium.Then the trophoblasts were exposed to 0.4 mT 50 Hz MF and/or "noise" MF respectively for different durations. Each exposure group was matched with one control group which was from the same villus and cultured with the same condition except the MF exposure. The concentrations of human chorionic gonadotropin (HCG) and progesterone in the culture medium were measured by immunofluorescence. Statistical significance of differences between means was determined by one way-ANOVA with P<0.05 considered significant. RESULT: 50 Hz MF inhibited the HCG and progesterone secretion significantly when exposure for 72 h (compared with control group, P<0.05). There was no significant change of HCG and progesterone secretion when trophoblasts were exposed to 0.4 mT "noise" MF within 72 h (compared with control group, P>0.05). However, by superimposing the "noise" MF, the inhibition of HCG and progesterone secretion of trophoblasts induced by 50 Hz MF was eliminated. CONCLUSION: The exposure to 50 Hz MF for long period could inhibit trophoblasts secreting HCG and progesterone, and the "noise" MF with the same intensity could eliminate the effects induced by 50 Hz MF.


Assuntos
Gonadotropina Coriônica/metabolismo , Vilosidades Coriônicas/efeitos da radiação , Campos Eletromagnéticos , Progesterona/metabolismo , Trofoblastos/efeitos da radiação , Transporte Biológico/efeitos da radiação , Secreções Corporais/efeitos da radiação , Células Cultivadas , Vilosidades Coriônicas/metabolismo , DNA/efeitos da radiação , Humanos , Ruído , Trofoblastos/metabolismo
13.
Artigo em Inglês | MEDLINE | ID: mdl-17556806

RESUMO

A full-length 1,043-base-pair cDNA clone encoding a chloroplast copper/zinc superoxide dismutase (Cu/Zn-SOD) of upland cotton was first isolated by rapid amplification of cDNA ends (RACE) from the leaves of the cotton (Gossypium hirsutum L.) variety 'CRI36'. Nucleotide sequence analysis of the clone revealed that it contained the complete coding sequence of the mature SOD isozyme subunit, along with a 60-amino acid transit peptide at N-terminal. The amino acid sequence predicted from the full-length clone showed 66%-74% homology with the amino acid sequences of Cu/Zn-SOD from several other plants. This gene was found to be expressed in the leaves and stems, but not in roots, flowers, and hypocotyls, indicating that the gene was expressed only in green tissues. Also, its expression was found to be most active at seedling stage and declined gradually in later development stages. Expression of this cotton Cu/Zn-SOD gene by using the pET-21a (+) expression vector in E. coli BL21 (DE3) led to the production of a novel 29 kD polypeptide with SOD enzyme activity, confirming that the cloned cotton Cu/Zn-SOD cDNA was indeed encoding a functioning SOD enzyme.


Assuntos
Cloroplastos/enzimologia , Gossypium/genética , Proteínas de Plantas/genética , Superóxido Dismutase/genética , Sequência de Aminoácidos , Northern Blotting , Southern Blotting , Clonagem Molecular , Escherichia coli/genética , Regulação Enzimológica da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Gossypium/enzimologia , Dados de Sequência Molecular , Proteínas de Plantas/metabolismo , Proteínas Recombinantes/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Homologia de Sequência de Aminoácidos , Superóxido Dismutase/metabolismo
14.
Artigo em Chinês | MEDLINE | ID: mdl-18070494

RESUMO

OBJECTIVE: To study apoptosis-related gene expression of human villous trophoblasts exposed to 50 Hz magnetic field and to investigate the possible mechanism of human reproductive health effects caused by 50 Hz magnetic field. METHODS: Cultured human villous trophoblasts were exposed to 50 Hz magnetic field at 0.4 mT for 6, 48, 72 hours. Gene expressions of Bcl-2, Bax, Caspase-3, p53 and Fas were analyzed using real-time reverse transcription polymerase chain reaction (RT-PCR) assay. RESULTS: Within 72 hours, the average fold change for each gene was near 1.00, and there was no significant difference on expression pattern in each gene between exposure and control groups (P > 0.05). CONCLUSION: 0.4 mT 50 Hz magnetic field does not affect the apoptosis-related gene expression of human villous trophoblasts in vitro.


Assuntos
Campos Magnéticos/efeitos adversos , Trofoblastos/metabolismo , Caspase 3/metabolismo , Células Cultivadas , Feminino , Regulação da Expressão Gênica , Humanos , Gravidez , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Proteína X Associada a bcl-2/metabolismo , Receptor fas/metabolismo
15.
World J Gastroenterol ; 10(12): 1740-5, 2004 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-15188497

RESUMO

AIM: To study interactions between hepatitis B virus (HBV) and interferon-alpha in liver- derived cells. METHODS: mRNAs were separately isolated from an HBV-transfected cell line (HepG(2)2.2.15) and its parental cell line (HepG(2)) pre- and post-interferon-alpha (IFN-alpha) treatment at 6, 24 and 48 h, followed by hybridization with a cDNA microarray filter dotted with 14 000 human genes. After hybridization and scanning of the arrays, the data were analyzed using ArrayGauge software. The microarray data were further verified by Northern blot analysis. RESULTS: Compared to HepG(2) cells, 14 genes with known functions were down-regulated 3 to 12- magnitudes, while 7 genes were up-regulated 3-13 magnitudes in HepG(2)2.2.15 cells prior to IFN-alpha treatment. After interferon-alpha treatment, the expression of four genes (vascular endothelial growth factor, tyrosine phosphate 1E, serine protein with IGF-binding motif and one gene of clathrin light chain) in HepG(2)2.2.15 were up-regulated, while one gene encoding a GTP-binding protein, two genes of interferon-induced kinases and two proto-oncogenes were further down- regulated. Interestingly, under IFN-alpha treatment, a number of differentially regulated genes were new ESTs or genes with unknown functions. CONCLUSION: The up-regulated genes in HepG(2)2.2.15 cell line suggested that under IFN-alpha treatment, these repressed cellular genes in HBV infected hepatocytes could be partially restored, while the down- regulated genes were most likely the cellular genes which could not be restored under interferon treatment. These down-regulated genes identified by microarray analysis could serve as new targets for anti-HBV drug development or for novel therapies.


Assuntos
Antivirais/farmacologia , Regulação Viral da Expressão Gênica/efeitos dos fármacos , Vírus da Hepatite B/genética , Hepatoblastoma , Interferon-alfa/farmacologia , Neoplasias Hepáticas , Linhagem Celular Tumoral/fisiologia , Linhagem Celular Tumoral/virologia , Humanos , Análise de Sequência com Séries de Oligonucleotídeos/normas , Reprodutibilidade dos Testes , Transfecção
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