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2.
Biol Bull ; 240(2): 105-117, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33939940

RESUMO

AbstractThe nudibranch Tritonia exsulans (previously Tritonia diomedea) is known to have behaviors and neurons that can be modified by perturbations of the Earth's magnetic field. There is no definitive evidence for how this magnetic sense is used in nature. Using an exploratory approach, we tested for possible effects of magnetic perturbations based on underwater video of crawling patterns in the slugs' natural habitat, with magnets of varying strength deployed on the substrate. For analysis, we used a paired comparison of tracks of animals between segments 25-50 cm distant from the magnets and segments of the same tracks 0-25 cm from the magnets, to determine whether any differences depended on the strength of the magnet. Most track measurements (length, displacement, velocity, and tortuosity) showed no such differences. However, effects were observed for the changes in track headings between successive points. These results showed that tracks had relatively higher heading variability when they moved closer to stronger magnets. We suggest that this supports a hypothesis that T. exsulans continuously uses a magnetic sense to help maintain straight-line navigation. Further specific testing of the hypothesis is now needed to verify this new possibility for how animals can benefit from a compass sense.


Assuntos
Gastrópodes , Lesma Marinha , Animais , Ecossistema , Imãs , Neurônios
3.
Hu Li Za Zhi ; 68(3): 97-107, 2021 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-34013511

RESUMO

The American Nurses Credentialing Center (ANCC) manages Magnet Recognition Program® certification. Candidates for this certification are required to pass a review comprising six compulsory documents and 84 sets of written documents in five model components as well as an onsite appraisal. The Magnet Recognition Program® for medical institutes is currently regarded as the highest honor in the nursing field. The series of measures necessary to establish a Magnet-recognized hospital is described in this article. Our hospital began preparation for recognition in January 2016, with the application submitted in May 2017. The required measures include establishing a Professional Practice Model, Governance Council, and National Database of Nursing Quality Indicators as well as implementing a mentoring plan. ANCC approved Magnet Recognition Program® recognition for our hospital in May 2020, making ours the first Magnet-recognized hospital in Taiwan. The nursing staff shared their experiences on their Magnet journey. Magnet-recognition demonstrates that a hospital is adequately equipped and trained to provide patients with outstanding nursing care and to operate an excellent nursing practice environment.


Assuntos
Imãs , Recursos Humanos de Enfermagem no Hospital , Credenciamento , Humanos , Taiwan , Estados Unidos
4.
Sensors (Basel) ; 21(7)2021 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-33808443

RESUMO

A magnetically-guided capsule endoscope, embedding flexible force sensors, is designed to measure the capsule-tissue interaction force. The flexible force sensor is composed of eight force-sensitive elements surrounding the internal permanent magnet (IPM). The control of interaction force acting on the intestinal wall can reduce patient's discomfort and maintain the magnetic coupling between the external permanent magnet (EPM) and the IPM during capsule navigation. A flexible force sensor can achieve this control. In particular, by analyzing the signals of the force sensitive elements, we propose a method to recognize the status of the motion of the magnetic capsule, and provide corresponding formulas to evaluate whether the magnetic capsule follows the motion of the external driving magnet. Accuracy of the motion recognition in Ex Vivo tests reached 94% when the EPM was translated along the longitudinal axis. In addition, a method is proposed to realign the EPM and the IPM before the loss of their magnetic coupling. Its translational error, rotational error, and runtime are 7.04 ± 0.71 mm, 3.13 ± 0.47∘, and 11.4 ± 0.39 s, respectively. Finally, a control strategy is proposed to prevent the magnetic capsule endoscope from losing control during the magnetically-guided capsule colonoscopy.


Assuntos
Cápsulas Endoscópicas , Fenômenos Mecânicos , Desenho de Equipamento , Humanos , Imãs , Movimento (Física)
5.
J Chromatogr A ; 1645: 462074, 2021 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-33848656

RESUMO

We prepared two-dimensional (2D) bimetallic metal-organic frameworks (Ni-ZIF-8) nanosheets by a simple solvent-free method at room temperature. The morphology and composition of Ni-ZIF-8 can be controlled through adding different amounts of Ni. And then, the 2D magnetic mesoporous nanosheets (Ni/ZnO@C) were synthesized by directly pyrolyzing Ni-ZIF-8 under argon atmosphere and explored as magnetic solid phase extraction (MSPE) adsorbents for the determination of nitroimidazole antibiotics (NIABs). Magnetic Ni nanoparticles embedded in carbon nanosheets uniformly resulted in high magnetization saturation of Ni/ZnO@C for easy separation. The Ni/ZnO@C can form hydrogen bond and π-π interaction with three NIABs resulting from their rich N-H containing imidazole, π-electron. Due to the high specific surface area and high mass transfer rate of 2D Ni/ZnO@C, the materials showed satisfactory adsorption capacity and rapid adsorption kinetics for NIABs. A rapid and effective method of Ni/ZnO@C-MSPE combined with high-performance liquid chromatography was proposed for the determination of NIABs. Several main parameters affecting MSPE were investigated. Under the optimal conditions, wide linear was achieved ranging from 0.1 to 500 µg⋅L-1 with a low detection limit of 0.025-0.05 µg⋅L-1. The established method has been successfully applied to analyze NIABs from environmental water samples with satisfactory recovery from 74.33 to 105.71%.


Assuntos
Antibacterianos , Nanopartículas Metálicas/química , Estruturas Metalorgânicas/química , Nitroimidazóis , Extração em Fase Sólida/métodos , Antibacterianos/análise , Antibacterianos/isolamento & purificação , Carbono/química , Cromatografia Líquida de Alta Pressão/métodos , Limite de Detecção , Modelos Lineares , Imãs/química , Nanoestruturas/química , Níquel/química , Nitroimidazóis/análise , Nitroimidazóis/isolamento & purificação
6.
J Chromatogr A ; 1645: 462104, 2021 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-33857676

RESUMO

A novel magnetic graphene oxide nanocomposite modified with polyaniline (Fe3O4@GO-PANI) was synthesized and applied for the magnetic solid-phase extraction of polycyclic aromatic hydrocarbons (PAHs) (i.e. fluorene, phenanthrene and pyrene) and nitrated polycyclic aromatic hydrocarbons (N-PAHs) (i.e. 2-nitrofluorene, 9-nitroanthracene, 1-nitropyrene and 3-nitrofluoranthene) prior to their determination by gas chromatography-mass spectrometry. The prepared nanomaterial was characterized by scanning electron microscopy, X-ray diffraction, and Fourier transform-infrared spectroscopy. The main experimental parameters affecting the extraction and desorption steps of the MSPE procedure were investigated and optimized. Under optimum conditions, coefficients of determination (r2) ranged between 0.9970 and 0.9995, limits of detection (LODs, S/N = 3) ranged between 0.04-0.05 ng mL-1 for PAHs and 0.01-0.11 ng mL-1 for N-PAHs, while the relative standard deviation for intra-day and inter-day repeatability were lower than 10.0% for PAHs and N-PAHs. The method was successfully applied to the analysis of tap, mineral and river water samples. Relative recoveries in spiked water samples ranged between from 91.6 to 114% and from 92.3 to 110% for PAHs and N-PAHs, respectively. The proposed method is simple, rapid, sensitive and the Fe3O4@GO-PANI sorbent can be reused for at least 15 times without significant decrease in extraction recovery.


Assuntos
Hidrocarbonetos Policíclicos Aromáticos , Extração em Fase Sólida/métodos , Sonicação/métodos , Poluentes Químicos da Água , Compostos de Anilina/química , Cromatografia Gasosa-Espectrometria de Massas , Grafite/química , Imãs , Nanocompostos/química , Hidrocarbonetos Policíclicos Aromáticos/análise , Hidrocarbonetos Policíclicos Aromáticos/isolamento & purificação , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/isolamento & purificação
7.
BMC Pediatr ; 21(1): 179, 2021 04 17.
Artigo em Inglês | MEDLINE | ID: mdl-33865355

RESUMO

BACKGROUND: The aim of this study was to characterize patients who ingested multiple rare-earth magnets, reveal the harm of rare-earth magnet foreign bodies in the digestive tract, and develop a clinical management algorithm. METHODS: This was a retrospective review of patients with rare-earth magnet foreign bodies in the digestive tract admitted to a university-affiliated pediatric medical center in China, between January 2016 and December 2019; the subset of medical data evaluated included clinical symptoms, signs, treatments and outcomes. RESULTS: A total of 51 cases were included in this study, including 36(70.6%) males and 15(29.4%) females. The magnets were passed naturally in 24(47.1%) patients and removed by intervention in 27(52.9%) patients, including 5(9.8%) cases by endoscopy and 22(43.1%) cases by surgery. Twenty-two (43.1%)cases had gastrointestinal obstruction, perforation, and fistula. Compared with the non-surgical group, the time of the surgical group from ingestion to arriving at the hospital was longer([80(5-336) vs 26(2-216)]hours, p < 0.001) while there was no significant difference in the mean age or the number of magnets swallowed. CONCLUSIONS: Magnets are attractive to children, but lead to catastrophic consequences including gastrointestinal obstruction, perforation, and surgical interventions when ingested multiple magnets. Endoscopic resection should be urgently performed in the presence of multiple magnets as early as possible within 24 h, even in asymptomatic patients.


Assuntos
Corpos Estranhos , Imãs , Criança , China/epidemiologia , Ingestão de Alimentos , Feminino , Corpos Estranhos/diagnóstico por imagem , Corpos Estranhos/cirurgia , Humanos , Masculino , Estudos Retrospectivos
8.
Food Chem ; 356: 129722, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-33836357

RESUMO

Rutin (RT), a widely distributed natural flavonoid compound, has been generally utilized as an important active ingredient owing to its considerable biomedical and economic value. Inspired by the structure features of densely-packed bayberry and well-orientated honeycomb, a novel type of magnetic molecularly imprinted polymers (HB-TI-MMIPs) with abundant high-affinity and uniformly-distributed binding sites was rationally constructed for the selective enrichment of RT from Sophora japonica. The polymerization conditions, physicochemical properties, and adsorption performance of the imprinted nanomaterials were systematically investigated. The optimized HB-TI-MMIPs display a high adsorption capacity, fast adsorption rate, and satisfactory selectivity towards RT. Meanwhile, the proposed analytical methodology using HPLC, with HB-TI-MMIPs as adsorbents, successfully applied to enrich and detect RT from Sophora japonica with high recoveries (87.2-94.6%) and good RSDs (lower than 4.3%). Therefore, the fabricated HB-TI-MMIPs with a fast magnetic responsivity and desirable adsorption performance would be attractive in plant active ingredients extraction fields.


Assuntos
Biomimética , Imãs/química , Polímeros Molecularmente Impressos/química , Myrica , Rutina/química , Sophora/química , Adsorção , Rutina/isolamento & purificação , Propriedades de Superfície
9.
J Prosthodont ; 30(5): 454-457, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33660377

RESUMO

The presence of a cleft lip and palate is associated with a number of complications and the oral rehabilitation for the improvement of speech, function and esthetics can involve conventional and surgical orthodontics, distraction osteogenesis, fixed and removable prosthodontics, providing obturation of open defects if required. This clinical report describes the prosthodontic management of a patient with a repaired cleft lip and palate with significant maxillary hypoplasia and primary concern of aesthetics with the use of a two-part hinged magnet retained removable prosthesis.


Assuntos
Fenda Labial , Fissura Palatina , Implantes Dentários , Fenda Labial/cirurgia , Fissura Palatina/cirurgia , Estética Dentária , Humanos , Imãs , Maxila/cirurgia
10.
J Laparoendosc Adv Surg Tech A ; 31(5): 526-529, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33784476

RESUMO

Background: Laparoscopic Nissen fundoplication is considered the current gold standard of surgical treatment of gastroesophageal reflux disease. Magnetic sphincter augmentation with the LINX® device was developed as a less technically challenging alternative that has proven to be a safe and effective surgical antireflux procedure. Despite rapid adoption of the robotic platform in many areas of general surgery, no studies have compared laparoscopic and robotic approaches to placement of the LINX device. This retrospective study is the first to compare the robotic platform with the laparoscopic approach for minimally invasive LINX placement. Methods: We conducted a retrospective review of a total cohort of 20 patients who underwent LINX placement with hiatal hernia repair at our institution. Half of the patients underwent surgery using laparoscopy and the other half with robotic technology. Patient characteristics, surgical outcomes, and charge differences were analyzed. Results: We found that there were no significant differences in hospital length of stay, surgical outcomes, use of proton pump inhibitors (PPIs) postoperatively, or postoperative dysphagia. Patients undergoing robotic surgery had longer operative time (139 ± 25 minutes versus 81 ± 14 minutes, P < .01), higher intraoperative charges ($8980 ± 275 versus $7239 ± 355, P < .01), and higher charges associated with their hospital stay ($45,037 ± 4112.41 versus $39,565 ± 3731.64, P < .01). Conclusions: In comparison with laparoscopic LINX procedures, robotic LINX does not offer superior surgical outcomes in terms of postoperative PPI use, dysphagia, or hospital length of stay. Robotic LINX procedures are associated with increased operative time and overall charges.


Assuntos
Fundoplicatura/métodos , Refluxo Gastroesofágico/cirurgia , Hérnia Hiatal/cirurgia , Herniorrafia/métodos , Laparoscopia/métodos , Imãs , Procedimentos Cirúrgicos Robóticos/métodos , Adulto , Idoso , Feminino , Seguimentos , Fundoplicatura/instrumentação , Refluxo Gastroesofágico/complicações , Hérnia Hiatal/complicações , Humanos , Laparoscopia/instrumentação , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Procedimentos Cirúrgicos Robóticos/instrumentação , Resultado do Tratamento
11.
Molecules ; 26(4)2021 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-33670480

RESUMO

One-pot reaction of the Schiff base N,N'-ethylene bis(salicylaldimine) (H2L), CoCl2.6H2O, and [Ph2SnCl2] in acetone produces the mixed valence CoIICoIII2 compound [CoIICoIII2(µ-L)2(Ph)2(µ-Cl)2]·(CH3)2CO·H2O (1). Our recent study already revealed that the same reaction mixtures in methanol or ethanol produced a heterometallic SnIVCoIII (2) or monometallic CoIII complex (3), respectively. Comparison of these organometallic systems shows that the 2,1-intermetallic Ph shift occurs in any of those solvents, but their relevant structural features (mononuclear, dinuclear-heterometallic, and trinuclear mixed valence) are solvent dependent. Geometrical structural rotation is also discussed among the related organometallic CoIICoIII2 systems. The AC magnetic susceptibility measurements indicate that 1 is a single molecule magnet (SMM), exhibiting a field-induced slow magnetic relaxation with two modes. The relaxation time for the low-frequency channel is as slow as τ~0.6 s at T = 2.0 K and BDC = 1.0 T.


Assuntos
Cobalto/química , Imãs/química , Solventes/química , Cristalografia por Raios X , Eletricidade , Campos Magnéticos , Conformação Molecular , Rotação , Temperatura
14.
Otol Neurotol ; 42(5): e536-e542, 2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-33534388

RESUMO

OBJECTIVE: To investigate whether ultrasound is a helpful and reliable diagnostic tool to survey the status of the magnet previous and after manual repositioning in patients with partially dislocated cochlear implant (CI) magnets and to assess the success rate of a manual repositioning maneuver. DESIGN: A prospective cohort study. SETTING: A tertiary referral medical center. PATIENTS: Patients with a cochlear implant who presented with magnet dislocation after magnetic resonance imaging (MRI) between June 1, 2019 and July 15, 2020. INTERVENTIONS: Manual repositioning of the partially dislocated CI magnet surveyed by pre- and post-interventional ultrasound. MAIN OUTCOME MEASURES: Rate of successfully diagnosed and manually repositioned magnets; complication rate and recurrence rate after initial manual repositioning maneuver. RESULTS: Nine patients presented with a partial magnet dislocation diagnosed by pre-interventional ultrasound following MRI (n = 9 magnets; three ♀; eight right-sided implants; 65.4 ±â€Š21.7 yr). All magnets were repositioned manually. The magnets were successfully repositioned at the first attempt in six out of eight patients. Two patients required a second and one patient a third attempt of manual repositioning. Post-interventional ultrasound confirmed the entirely restored magnet position in all cases. During the mean follow-up period of 7.3 months (±5.4 mo) no patient experienced any complication or recurrent dislocation of the respective magnet. CONCLUSION: Manual magnet repositioning is a feasible and reliable method with a high success rate for partially dislocated CI magnets. The pre-interventional diagnosis as well as the post-interventional confirmation of the magnet status can be effectively determined by ultrasound. Thus, manual magnet repositioning and ultrasound investigation can be advocated as first-line therapeutic and diagnostic instruments when dealing with partial magnet dislocation.


Assuntos
Implante Coclear , Implantes Cocleares , Reposicionamento de Medicamentos , Humanos , Imageamento por Ressonância Magnética , Imãs , Estudos Prospectivos
15.
Molecules ; 26(4)2021 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-33557181

RESUMO

The effective spin Hamiltonian method has drawn considerable attention for its power to explain and predict magnetic properties in various intriguing materials. In this review, we summarize different types of interactions between spins (hereafter, spin interactions, for short) that may be used in effective spin Hamiltonians as well as the various methods of computing the interaction parameters. A detailed discussion about the merits and possible pitfalls of each technique of computing interaction parameters is provided.


Assuntos
Fenômenos Magnéticos , Imãs , Modelos Teóricos
16.
Zhongguo Yi Liao Qi Xie Za Zhi ; 45(1): 32-36, 2021 Feb 08.
Artigo em Chinês | MEDLINE | ID: mdl-33522173

RESUMO

The magnetic anchoring lung nodule positioning device is composed of a target magnet, an anchor magnet, a coaxial puncture needle and a puncture navigation template, through these, a new type of accurate positioning technology for small pulmonary nodules is derived. The device inserts the target magnet into the both sides nearby the lung nodule under the guidance of CT. Helped by the mutual attraction of the two target magnets, they can be fixed in the lung tissue, avoiding the movement in the lung, and accurately positioning the target lung nodule before surgery. In thoracoscopic surgery, the anchor magnet and the target magnet attract each other to achieve the purpose of positioning the target nodule. The device uses the characteristics of non-contact suction of magnetic materials biomedical engineering technology, eliminating the previous procedure of direct interaction with the positioning marks, finally achieves the target of precise positioning of lung nodules and rapid surgical removal.


Assuntos
Nódulo Pulmonar Solitário , Humanos , Pulmão , Neoplasias Pulmonares , Fenômenos Magnéticos , Imãs , Cirurgia Torácica Vídeoassistida , Tomografia Computadorizada por Raios X
17.
ACS Appl Mater Interfaces ; 13(3): 3694-3700, 2021 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-33442969

RESUMO

The majority of current methods of isolating circulating tumor cells (CTCs) rely on a biomarker. However, the isolation efficiency may be compromised due to the heterogeneity of CTCs. In this work, a simple and broad-spectrum method is established to efficiently isolate the heterogeneous CTCs from patient blood samples using tannic acid (TA)-functionalized magnetic nanoparticles (MNPs). The TA-functionalized MNPs (MNPs-TA) inhibit the nonspecific adhesion of peripheral blood mononuclear cell (PBMC) and enhance cancer cell capture, resulting from the unique interaction between TA and glycocalyx on cancer cells. The MNPs-TA was demonstrated to effectively capture seven kinds of cancer cells (HeLa, PC-3, T24, MAD-MB-231, MCF-7, HT1080, A549) from artificial samples (62.3-93.7%). Moreover, this epithelial cell adhesion molecule (EpCAM)-independent CTC isolation method was also tested using clinical blood samples from patients with different cancers (21 patients), which may provide a universal tool to detect CTCs in the clinic.


Assuntos
Separação Celular/métodos , Imãs/química , Nanopartículas/química , Neoplasias/patologia , Células Neoplásicas Circulantes/patologia , Taninos/química , Adulto , Idoso , Linhagem Celular Tumoral , Molécula de Adesão da Célula Epitelial/análise , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
18.
ACS Appl Mater Interfaces ; 13(3): 3622-3630, 2021 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-33443402

RESUMO

Extracellular vesicles (EVs) have emerged as important carriers for intercellular communication and biological sources for diagnosis and therapeutics. Low efficiency in EV isolation from biofluids, however, severely restricts their downstream characterization and analysis. Here, we introduced a novel strategy for EV isolation from urine for prostate cancer diagnosis using bifunctionalized magnetic beads through high affinity Ti(IV) ions and the insertion of a phospholipid derivative, 1,2-distearoyl-sn-glycero-3-phosphoethanolamine, into the EV membrane synergistically. We demonstrated its efficient isolation of EVs from urine samples with low contamination, high recovery (>80%), and short separation time (within 1 h), resulting in the identification of 36,262 unique EV peptides corresponding to 3302 unique proteins and 3233 unique phosphopeptides representing 1098 unique phosphoproteins using only 100 µL and 5 mL urine samples, respectively. Coupled with trapped ion mobility spectrometry and parallel accumulation-serial fragmentation for phosphosite-specific resolution, quantitative phosphoproteomics of urine samples from prostate cancer patients and healthy individuals revealed 121 upregulated phosphoproteins in cancer patients in contrast to the healthy group. These particular advantages indicate that the novel bifunctional material enables sensitive EV phosphoproteomic analysis for noninvasive biomarker screening and early cancer diagnosis.


Assuntos
Vesículas Extracelulares/química , Fosfoproteínas/análise , Neoplasias da Próstata/urina , Proteômica/métodos , Urina/química , Humanos , Imãs/química , Masculino , Fosfopeptídeos/análise , Fosfopeptídeos/urina , Fosfoproteínas/urina , Neoplasias da Próstata/diagnóstico
20.
Molecules ; 26(3)2021 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-33498976

RESUMO

Molecular magnets attached to carbon nanotubes (CNT) are being studied as potential candidates for developing spintronic and quantum technologies. However, the functionalization routes used to develop these hybrid systems can drastically affect their respective physiochemical properties. Due to the complexity of this systems, little work has been directed at establishing the correlation between the degree of functionalization and the magnetic character. Here, we demonstrate the chemical functionalization degree associated with molecular magnet loading can be utilized for controlled tuning the magnetic properties of a CNT-lanthanide hybrid complex. CNT functionalization degree was evaluated by interpreting minor Raman phonon modes in relation to the controlled reaction conditions. These findings were exploited in attaching a rare-earth-based molecular magnet (Gd-DTPA) to the CNTs. Inductively coupled plasma mass spectrometry, time-of-flight secondary ion mass spectrometry and super conducting quantum interference device (SQUID) measurements were used to elucidate the variation of magnetic character across the samples. This controlled Gd-DTPA loading on the CNT surface has led to a significant change in the nanotube intrinsic diamagnetism, showing antiferromagnetic coupling with increase in the Weiss temperature with respect to increased loading. This indicates that synthesis of a highly correlated spin system for developing novel spintronic technologies can be realized through a carbon-based hybrid material.


Assuntos
Elementos da Série dos Lantanídeos/química , Imãs/química , Nanotubos de Carbono/química , Gadolínio DTPA/química , Fenômenos Magnéticos , Microscopia Eletrônica de Transmissão , Nanotubos de Carbono/ultraestrutura , Espectrometria de Massa de Íon Secundário , Análise Espectral Raman
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