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1.
Anal Chem ; 95(4): 2348-2355, 2023 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-36609163

RESUMEN

To figure out the reason for the drawback of the stored waveform inverse Fourier transform (SWIFT) waveform and realize the high-resolution ion isolation on the miniaturized linear ion trap mass spectrometer, we studied the efficiency that ions can be excited under different excitation durations and amplitudes at different frequencies and compared the overlap ratios of the effective excitation frequency bandwidths of the adjacent ions. According to this, we proposed a new coarse-to-fine isolation waveform named SWIFTSIN. By superposing one or more sinusoidal waveforms on the SWIFT waveform and modulating the phases of the superposed sinusoidal waveforms, the generated SWIFTSIN waveform can achieve unit mass isolation on the miniaturized linear ion trap mass spectrometer without reducing the intensity of the target ion. The isolation ability of the SWIFTSIN waveform was verified by isolating a single isotope peak in the mixed samples.

2.
Anal Chem ; 95(47): 17407-17415, 2023 Nov 28.
Artículo en Inglés | MEDLINE | ID: mdl-37963290

RESUMEN

The mass spectrometer is an important tool for modern chemical analysis and detection. Especially, the emergence of miniature mass spectrometers has provided new tools for field analysis and detection. The resolution of a mass spectrometer reflects the ability of the instrument to discriminate between adjacent mass-to-charge ratio ions, and the higher the resolution, the better the discrimination of complex mixtures. Quadrupole ion traps are generally considered as a low-resolution mass spectrometry method, but they have gained wide attention and development in recent years because of their suitability for miniaturization and high qualitative capability. For an ion trap mass spectrometer, the mass sensitivity and resolution can be mutually constrained and need to be balanced by setting an appropriate scanning speed. In this study, a super-resolution U-net algorithm (SR-Unet) is proposed for ion trap mass spectrometry, which can estimate the possible ions from the overlapping ion peaks of low-resolution spectra and improve the equivalent resolution while ensuring sufficient sensitivity and analysis speed of the instrument. By determining the mass spectra of a linear ion trap mass spectrometer (LTQ XL) in Turbo and Normal scan modes, the same unit mass resolution as that at a scan speed of 16,667 Da/s was successfully obtained at 125,000 Da/s. Also, the experiments demonstrated that the algorithm is capable of the mass-to-charge ratio and instrument migration. SR-Unet can be migrated and applied to a miniature mass spectrometer for cruise detection of volatile organic compounds (VOCs), and the identification of VOC species in Photochemical Assessment Monitoring Stations (PAMS) was improved from 31 to 50 species with the same monitoring and analysis speed requirement. Further, super-unit mass resolution peptide detection was achieved on a miniature mass spectrometer with the help of the SR-Unet algorithm, which reduced the full width at half-maxima (FWHM) of bradykinin divalent ions (m/z 531) from 0.35 to 0.15 Da at a scan speed of 375 Da/s and improved the equivalent resolution to 3540. The proposed method provides a new idea to enhance the field mixture detection capability of miniature ion trap mass spectrometers.

3.
Am Heart J ; 265: 180-190, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37611856

RESUMEN

BACKGROUND AND AIMS: Computed tomography-derived fractional flow reserve (CT-derived FFR) algorithms have emerged as promising noninvasive methods for identifying hemodynamically significant coronary artery disease (CAD). However, its broad adaption is limited by the complex workflow, slow processing, and supercomputer requirement. Therefore, CT-derived FFR solutions capable of producing fast and accurate results could help deliver time-sensitive results rapidly and potentially alter patient management. The current study aimed to determine the diagnostic performance of a novel CT-derived FFR algorithm, esFFR, on patients with CAD was evaluated. METHODS: 329 patients from 6 medical centers in China were included in this prospective study. CT-derived FFR calculations were performed on 350 vessels using the esFFR algorithm using patients' presenting coronary computed tomography angiography (CCTA) images, and results and processing speed were recorded. Using invasive FFR measurements from direct coronary angiography as the reference standard, the diagnostic performance of esFFR and CCTA in detecting hemodynamically significant lesions were compared. Post-hoc analyses were performed for patients with calcified lesions or stenoses within the CT-derived FFR diagnostic "gray zone." RESULTS: The esFFR values correlated well with invasive FFR. The sensitivity, specificity, accuracy, positive and negative predictive value for esFFR were all above 90%. The overall performance of esFFR was superior to CCTA. Coronary calcification had minimal effects on esFFR's diagnostic performance. It also maintained 85% of diagnostic accuracy for "gray zone" lesions, which historically was <50%. The average esFFR processing speed was 4.6 ± 1.3 minutes. CONCLUSIONS: The current study demonstrated esFFR had high diagnostic efficacy and fast processing speed in identifying hemodynamically significant CAD.

4.
Molecules ; 28(11)2023 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-37299001

RESUMEN

Acorus tatarinowii Schott (A. tatarinowii) is a natural medicinal plant. It plays an indispensable role in the treatment of diseases by the empirical medicine system and has achieved remarkable curative effects. A. tatarinowii is often used to treat various diseases, such as depression, epilepsy, fever, dizziness, heartache, stomachache, etc. More than 160 compounds of different structural types have been identified in A. tatarinowii, including phenylpropanoids, terpenoids, lignans, flavonoids, alkaloids, amides, and organic acids. These bioactive ingredients make A. tatarinowii remarkable for its pharmacological effects, including antidepressant, antiepileptic, anticonvulsant, antianxiety, neuroprotective, antifatigue, and antifungal effects, improving Alzheimer's disease, and so on. It is noteworthy that A. tatarinowii has been widely used in the treatment of brain diseases and nervous system diseases and has achieved satisfactory therapeutic effects. This review focused on the research publications of A. tatarinowii and aimed to summarize the advances in the botany, traditional uses, phytochemistry, and pharmacology, which will provide a reference for further studies and applications of A. tatarinowii.


Asunto(s)
Acorus , Botánica , Lignanos , Acorus/química , Extractos Vegetales/farmacología , Extractos Vegetales/uso terapéutico , Extractos Vegetales/química , Antidepresivos , Fitoquímicos/farmacología , Fitoquímicos/uso terapéutico , Etnofarmacología
5.
Clin Lab ; 68(7)2022 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-35975519

RESUMEN

BACKGROUND: Hematology analyzers provide quick and accurate results in most situations. However, spurious results related to the parameters from the complete blood count (CBC) may be observed in several instances. False increases in WBC count can occur for many reasons, including erythroblasts, insufficiently lysed red blood cells (RBC), platelet aggregates, lipids, and cryoglobulins. However, cases of pseudoleukocytopenia due to plasma related factors are rare. METHODS AND RESULTS: Here, we report a case of pseudoleukocytopenia in CBC test. It was identified by the peripheral blood smears and different scatter plots of WNR and WDF channel. The interference from plasma was con-firmed by simulating the state of blood in the WBC channel and plasma exchange. CONCLUSIONS: It was confirmed that the interference of pseudoleukocytopenia was from the plasma. This may be due to the high amount of albumin and other therapeutic drug reactions. Observation of peripheral blood smears and scatter plots can identify this interference.


Asunto(s)
Plaquetas , Eritrocitos , Recuento de Células Sanguíneas , Recuento de Eritrocitos , Humanos , Recuento de Leucocitos
6.
Int J Mol Sci ; 23(7)2022 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-35408959

RESUMEN

Trigeminal neuralgia (TN) is a complex orofacial pain syndrome characterized by the paroxysmal onset of pain attacks in the trigeminal distribution. The underlying mechanism for this debilitating condition is still not clearly understood. Decades of basic and clinical evidence support the demyelination hypothesis, where demyelination along the trigeminal afferent pathway is a major driver for TN pathogenesis and pathophysiology. Such pathological demyelination can be triggered by physical compression of the trigeminal ganglion or another primary demyelinating disease, such as multiple sclerosis. Further examination of TN patients and animal models has revealed significant molecular changes, channelopathies, and electrophysiological abnormalities in the affected trigeminal nerve. Interestingly, recent electrophysiological recordings and advanced functional neuroimaging data have shed new light on the global structural changes and the altered connectivity in the central pain-related circuits in TN patients. The current article aims to review the latest findings on the pathophysiology of TN and cross-examining them with the current surgical and pharmacologic management for TN patients. Understanding the underlying biology of TN could help scientists and clinicians to identify novel targets and improve treatments for this complex, debilitating disease.


Asunto(s)
Esclerosis Múltiple , Neuralgia , Neuralgia del Trigémino , Animales , Dolor Facial/patología , Humanos , Esclerosis Múltiple/patología , Neuralgia/patología , Nervio Trigémino/metabolismo , Neuralgia del Trigémino/metabolismo
7.
Small ; 17(30): e2100970, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34145736

RESUMEN

Magnetic-dielectric property plays a critical significance for the functional expression toward advanced materials. Within nanoscale, the simultaneous regulation of the electrical and magnetic properties of electromagnetic (EM) wave absorption materials faces huge challenges. Herein, using the metal-organic frameworks (MOF) as templates, highly-dispersed ZnO and Co nanoparticles are uniformly confined inside graphited N-doped carbon skeleton, constructing the balanced EM property in the Co@NC-ZnO absorbers. Meanwhile, a dynamics and symmetrical morphology optimization of MOF-derived Co@NC-ZnO are dependent on the Co/Zn mass ratio and adjusting MOF frameworks, which evolves from the cube, truncated cube, dodecahedron, and to the final microsphere. Simultaneously, both the electronic conduction network and magnetic coupling network are compatible together in the in situ transformed Co@NC-ZnO system. Boosted magnetic responding ability and unique magnetic coupling are verified by the off-axis electronic holography. Plentiful heterojunction interfaces and special electronic conduction paths can be built in this Co-Zn-MOF derivatives, facilitating the dielectric loss behaviors. As expected, MOF-derived Co@NC-ZnO absorber displays outstanding EM wave absorption ability with strongest reflection loss value of -69.6 dB at only 1.9 mm thickness and wideband absorption covering 6.8 GHz at 2.4 mm. Confined EM balance provides new design strategy toward MOF-derived excellent MA materials and functional devices.

8.
Small ; 17(30): e2100283, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34145737

RESUMEN

1D tubular micro-nano structural materials have been attracting extensive attention in the microwave absorption (MA) field for their anisotropy feature, outstanding impedance matching, and electromagnetic energy loss capability. Herein, unique double-shelled Sn@Mo2 C/C tubes with porous Sn inner layer and 2D Mo2 C/C outer layer are successfully designed and synthesized via a dual-template method. The composites possess favorable MA performance with an effective absorption bandwidth of 6.76 GHz and a maximum reflection loss value of -52.1 dB. Specifically, the rational and appropriate construction of Sn@Mo2 C/C tubes promotes the multi-path electron transfer in the composites to optimize the dielectric constant and consequently to enhance the capacity of electromagnetic wave energy dissipation. Three mechanisms dominate the MA process: i) the conductive loss resulted from the rapid electron transmission due to the novel 1D hollow coaxial multi-shelled structure, especially the metallic Sn inner layer; ii) the polarization loss caused by abundant heterogeneous interfaces of Sn-Mo2 C/C and Mo2 CC from the precise double-shelled structure; iii) the capacitor-like loss by the potential difference between Mo2 C/C nanosheets. This work hereby sheds light on the design of the 1D hierarchical structure and lays out a profound insight into the MA mechanism.

9.
Small ; 17(3): e2005227, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33350102

RESUMEN

Achieving strong adsorption and catalytic ability toward polar lithium polysulfide species (LiPSs) of the sulfur host in lithium-sulfur (Li-S) batteries is essential for their electrochemical cyclic stability. Herein, a strategy of "self-termination of ion exchange" is put forward to synthesize the novel yolk-shell sulfur host composed of ZnO nanoparticles confined in Co-doped NiO (CDN) polyhedron (ZCCDN). After sulfur infiltration, the obtained S/ZCCDN cathode achieves excellent performance of 738.56 mAh g-1 after 500 cycles at 0.5 C with a very low capacity decay rate of only 0.048% per cycle. Even at 1 C, 501.05 mAh g-1 could be retained after 500 cycles, suggesting a capacity decay ratio of only 0.076% per cycle. The good cycle performance is attributed to the improved LiPSs' conversion kinetics, which originates from ZCCDN's sturdy chemical affinity and strong catalytic ability to polar LiPSs. For the first time, by electron holography, the local interfacial polarization electric field is clarified to be existed in the material which is conducive to the capture of LiPSs and the migration of electrons and Li+ from the mesopores. This work provides a rational way for the use of zeolitic imidazolate frameworks (ZIFs) and development of cathode materials for Li-S batteries.

10.
Pain Med ; 22(11): 2700-2707, 2021 Nov 26.
Artículo en Inglés | MEDLINE | ID: mdl-34320638

RESUMEN

OBJECTIVES: To describe the method and clinical efficacy of awake computed tomography (CT)-guided percutaneous balloon compression (PBC) as a treatment for trigeminal neuralgia (TN). DESIGN: In this case series, patients with TN were treated with awake CT-guided PBC and followed up for treatment efficacy and complications for 12 months. SETTING: A single-center study. SUBJECTS: A total of 66 patients with medical treatment-refractory TN were recruited for the study. METHODS: The procedure was performed under moderate sedation. A balloon catheter was inserted through a trocar needle to reach Meckel's cavity under CT guidance. The position and optimal shape of the contrast-filled balloon were confirmed with CT three-dimensional reconstruction. Compression of the trigeminal ganglion was considered complete when the patient notified operators about facial hypoesthesia or the resolution of TN symptoms. All patients were followed up monthly for 12 months to monitor treatment efficacy and complications. RESULTS: The average trigeminal ganglion compression time was 272 ± 81 seconds, at which point the patients reported significant facial hypoesthesia compared with the contralateral side or resolution of triggered pain in the affected area. All patients had resolution of TN symptoms for 6 months, with a 1-year recurrence rate of 13%. The overall safety profile was improved with the technique described in this study. Side effects, such as hypoesthesia and mastication weakness, were overall mild and did not impact patients' quality of life. Some complications that historically have been associated with PBC, such as diplopia and keratitis, were not present. CONCLUSIONS: This new awake CT-guided PBC technique produces better outcomes than the traditional PBC under fluoroscopy guidance and general anesthesia.


Asunto(s)
Neuralgia del Trigémino , Humanos , Calidad de Vida , Tomografía Computarizada por Rayos X , Resultado del Tratamiento , Ganglio del Trigémino , Neuralgia del Trigémino/diagnóstico por imagen , Neuralgia del Trigémino/terapia , Vigilia
11.
Mol Pain ; 16: 1744806920928619, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32496847

RESUMEN

Chronic pain has detrimental effects on one's quality of life. However, its treatment options are very limited, and its underlying pathogenesis remains unclear. Recent research has suggested that fragile X mental retardation protein is involved in the development of chronic pain, making it a potential target for prevention and treatment. The current review of literature will examine the function of fragile X mental retardation protein and its associated pathways, through which we hope to gain insight into how fragile X mental retardation protein may contribute to nociceptive sensitization and chronic pain.


Asunto(s)
Dolor Crónico/metabolismo , Proteína de la Discapacidad Intelectual del Síndrome del Cromosoma X Frágil/metabolismo , Animales , Proteína de la Discapacidad Intelectual del Síndrome del Cromosoma X Frágil/química , Humanos , Canales Iónicos/metabolismo , Neuronas/metabolismo , Neuronas/patología , Transducción de Señal , Serina-Treonina Quinasas TOR/metabolismo
12.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 42(2): 147-153, 2020 Apr 28.
Artículo en Zh | MEDLINE | ID: mdl-32385019

RESUMEN

Objective To investigate the risk factors associated with acute renal failure (ARF) after thoracoabdominal aortic aneurysm (TAAA) surgery. Methods A total of 156 patients underwent TAAA repair between January 2009 and December 2017. Renal failure was defined based on the Kidney Disease Improving Global Outcomes criteria. The patients were divided into ARF group and non-ARF group based on the presence/absence of postoperative ARF. The risk factors of ARF were analyzed by univariate analysis and multivariate logistic analysis. Results The subjects included 111 males and 45 females aged (40.4±10.9) years (range:19-65 years). The surgical reasons included aortic dissection (n=130,83.3%),aneurysm (n=22,14.1%),and pseudoaneurysm (n=4,2.6%). The degrees of repair included Crawford extent I in 6 patients (3.8%),extent Ⅱ in 128 patients (82.1%),extent Ⅲ in 20 patients (12.8%),and extent Ⅳ in 2 patients(1.3%). There were 3 patients presented with aortic rupture and 6 patients received emergent operations. Nine patients (5.8%) died within 30 days after surgery,and 8 patients (5.1%) suffered from permanent paraplegia. Thirty-six patients (23.1%) had ARF after surgery,and 18 of them needed dialysis. Multivariate logistic analysis showed that smoking (OR =2.637,95%CI=1.113-6.250,P=0.028),packed red blood cell usage in operation (≥6 U) (OR =5.508,95%CI=2.144-11.930,P=0.000),reoperation for bleeding (OR=3.529,95%CI=1.298-9.590,P=0.013) were independent risk factors for ARF after TAAA repair. Conclusion Smoking,packed red blood cell usage in operation (≥6 U),reoperation for bleeding are the independent risk factors of ARF after TAAA surgery.


Asunto(s)
Lesión Renal Aguda/etiología , Aneurisma de la Aorta Torácica/cirugía , Implantación de Prótesis Vascular/efectos adversos , Complicaciones Posoperatorias , Adulto , Anciano , Transfusión Sanguínea , Femenino , Humanos , Masculino , Persona de Mediana Edad , Reoperación , Estudios Retrospectivos , Factores de Riesgo , Fumar , Resultado del Tratamiento , Adulto Joven
13.
J Card Surg ; 34(11): 1273-1278, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31475407

RESUMEN

OBJECTIVE: Kommerell diverticulum with aortic dissection involving aortic arch is a rare but troublesome condition. The purpose of this study is to summarize the experience and strategy of surgical treatment. METHOD: From November 2015 to January 2018, seven consecutive patients underwent surgical treatment in our institution. Three patients with acute type A aortic dissection and one patient with acute type B aortic dissection received total arch replacement and frozen elephant trunk (FET) implantation through median sternotomy. Three patients with chronic type B aortic dissection underwent total aortic arch and descending aorta replacement through median sternotomy and lateral thoracotomy. RESULT: There were seven male patients whose median age was 42.3 ± 11.7 (from 14 to 54) years old. There was no perioperative death in this study. One patient had postoperative critical illness polyneuropathy and required prolonged mechanical ventilation (485 hours) and recovered finally. Follow up was completed for all seven patients with a median follow-up time of 7 (3-46) months. One patient with type A dissection developed aneurysm of the descending aorta distal to the FET and received reintervention. No clinical events and abnormal computed tomography manifestations were found in the other seven patients. CONCLUSION: Total arch replacement and FET through single median incision is a reliable method for Kommerell diverticulum associated with acute dissection involving arch. For Kommerell diverticulum associated with chronic type A or B aortic dissection involving aortic arch, graft replacement by double or single incision is safe and appropriate.


Asunto(s)
Aorta Torácica/cirugía , Aneurisma de la Aorta/cirugía , Disección Aórtica/cirugía , Divertículo/cirugía , Humanos
14.
J Integr Neurosci ; 18(2): 117-126, 2019 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-31321952

RESUMEN

It has been well established that mammalian sterile 20-like 1 (MST1) functions as a suppressor via regulating cell progression in many tumors. However, the molecular mechanism of MST1 on regulating glioma progression remains unclear. Here, we discovered that MST1 was robustly down-regulated in glioma tissues and cells. Functional analysis showed that over-expression of MST1 downregulated viability and colony formation and promoted apoptosis of glioma cells. Our results also identified that MST1 positively regulated expression of SIRT6 (Sirtuin 6) via transcriptional factor FOXO3a (Forkhead box O3a). Furthermore, the functional role of MST1 in glioma cell viability (or apoptosis) were significantly reversed after knocking down of SIRT6. Our research indicates that MST1 is a potential biomarker for the prognosis and diagnosis of glioma and provides new direction on the molecular mechanism of glioma progression and development.


Asunto(s)
Apoptosis , Neoplasias Encefálicas/metabolismo , Glioma/metabolismo , Proteínas Serina-Treonina Quinasas/metabolismo , Sirtuinas/metabolismo , Adulto , Biomarcadores de Tumor/metabolismo , Línea Celular Tumoral , Supervivencia Celular , Femenino , Proteína Forkhead Box O3/metabolismo , Humanos , Péptidos y Proteínas de Señalización Intracelular , Masculino , Persona de Mediana Edad , Regulación hacia Arriba
15.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 41(4): 464-471, 2019 Aug 30.
Artículo en Zh | MEDLINE | ID: mdl-31484607

RESUMEN

Objective To evaluate the early and midterm results of surgical repair of thoracoabdominal aortic aneurysm(TAAA)in patients with Marfan syndrome(MFS). Methods The clinical data of patients with MFS undergoing TAAA repair in Fuwai Hospital between January 2009 and December 2017 were retrospectively analyzed.These patients were divided into two groups:MFS group(n=58)and non-MFS group(n=98).The baseline data,early postoperative results,and midterm follow-up outcomes were compared between these two groups. Results MFS patients were significantly younger(32 years old vs. 45 years old,t=9.603,P=0.000)and more frequently had a history of aortic aneurysm or dissection(19% vs. 0,χ 2=19.996,P=0.000)than non-MFS patients.However,the proportions of males and smokers were significantly lower when compared with non-MFS patients(55.2% vs. 80.6%,χ 2=11.489,P=0.001;13.8% vs. 46.9%,χ 2=17.686,P=0.001).There was no significant difference in proportion of emergency operation,prophylactic cerebrospinal fluid drainage,operation time,intra-operative circulation management,and intra-operative blood transfusion(all P>0.05).The 30-day mortality rate was significantly lower in MFS group than in non-MFS group(0 vs. 9.2%, [Formula: see text]=5.034,P=0.025). Conclusions For patients with MFS,TAAA repair provides lower 30-day mortality and comparative middle-term survival.However,the re-intervention rate is higher among MFS patients,highlighting the importance of close follow-up.


Asunto(s)
Aneurisma de la Aorta Torácica/cirugía , Implantación de Prótesis Vascular , Síndrome de Marfan/complicaciones , Adulto , Disección Aórtica , Aneurisma de la Aorta Torácica/complicaciones , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Resultado del Tratamiento
16.
Angew Chem Int Ed Engl ; 58(20): 6650-6653, 2019 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-30908799

RESUMEN

Reported herein is the synthesis of benzofused six-membered S-heterocycles by intramolecular dehydrogenative C-S coupling using a modular flow electrolysis cell. The continuous-flow electrosynthesis not only ensures efficient product formation, but also obviates the need for transition-metal catalysts, oxidizing reagents, and supporting electrolytes. Reaction scale-up is conveniently achieved through extended electrolysis without changing the reaction conditions and equipment.

17.
Anal Chem ; 90(7): 4514-4520, 2018 04 03.
Artículo en Inglés | MEDLINE | ID: mdl-29488746

RESUMEN

Measuring the ion distribution pattern in a drift tube under atmospheric pressure is very useful for studies of ion motion and design of ion mobility spectrometers (IMS); however, no mature method is available for conducting such measurements at present. We propose a simple and low-cost technique for profiling the two-dimensional ion distribution in any cross section of a drift tube. Similar to particle-image velocimetry, we first send sample ions with fluorescence properties into the drift tube and use a receiving plate to collect and accumulate them. Then, the receiving plate is illuminated by exciting light, and the ion distribution appears as a fluorescence image. In this study, Rhodamine 6G was selected as a typical fluorescence-tracer particle. Electrospray ionization (ESI) was chosen as an ionization source to keep the fluorophore undamaged. A plasma-cleaned coverslip was placed at the detection position as a receiving plate. When a layer of ions was collected, the slide was placed under the exciting light with a wavelength of 473 nm. A camera with a 490 nm high-pass light filter was used to capture the fluorescence image representing the ion distribution. The measured-ion detection efficiency of the method was 156 ion/dN, which is equivalent to the level of IonCCD. In addition, we studied the ion-passing characteristics of a Bradbury-Nielsen (BN) ion shutter and the ion-focusing effect in the drift tube using this method. The two-dimensional ion-distribution images behind the ion shutter and the images of the focused ion spot were first observed experimentally. Further theoretical analysis yielded the same conclusions as the experimental results, proving the feasibility of this method and producing a deeper understanding of ion motion in the IMS. This method has promising prospective application to the design, debugging, and optimization of IMS instruments and hyphenated systems.

18.
Plant Cell Environ ; 41(5): 1052-1064, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-28776692

RESUMEN

Brassinosteroids (BRs) regulate plant development and stress response. Although much has been learned about their roles in plant development, the mechanisms by which BRs regulate plant stress tolerance remain unclear. Chilling is a major stress that adversely affects plant growth. Here, we report that BR positively regulates chilling tolerance in tomato. BR partial deficiency aggravated chilling-induced oxidized protein accumulation, membrane lipid peroxidation, and decrease of maximum quantum efficiency of photosystem II (Fv/Fm). By contrast, overexpression of BR biosynthetic gene Dwarf or treatment with 24-epibrassinolide (EBR) attenuated chilling-induced oxidative damages and resulted in an increase of Fv/Fm. BR increased transcripts of RESPIRATORY BURST OXIDASE HOMOLOG1 (RBOH1) and GLUTAREDOXIN (GRX) genes, and BR-induced chilling tolerance was associated with an increase in the ratio of reduced/oxidized 2-cysteine peroxiredoxin (2-Cys Prx) and activation of antioxidant enzymes. However, RBOH1-RNAi plants failed to respond to EBR as regards to the induction of GRX genes, activation of antioxidant capacity, and attenuation of chilling-induced oxidative damages. Furthermore, silencing of GRXS12 and S14 compromised EBR-induced increases in the ratio of reduced/oxidized 2-Cys Prx and activities of antioxidant enzymes. Our study suggests that BR enhances chilling tolerance through a signalling cascade involving RBOH1, GRXs, and 2-Cys Prx in tomato.


Asunto(s)
Antioxidantes/metabolismo , Brasinoesteroides/metabolismo , Glutarredoxinas/metabolismo , Reguladores del Crecimiento de las Plantas/metabolismo , Transducción de Señal , Solanum lycopersicum/fisiología , Frío , Glutarredoxinas/genética , Peróxido de Hidrógeno/metabolismo , NADPH Oxidasas/genética , NADPH Oxidasas/metabolismo , Oxidación-Reducción , Peroxirredoxinas/genética , Peroxirredoxinas/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Estrés Fisiológico
19.
Chemistry ; 24(2): 487-491, 2018 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-29125202

RESUMEN

A catalyst- and supporting electrolyte-free method for electrochemical dehydrogenative C-S bond formation in continuous flow has been developed. A broad range of N-arylthioamides have been converted to the corresponding benzothiazoles in good to excellent yields and with high current efficiencies. This transformation is achieved using only electricity and laboratory grade solvent, avoiding degassing or the use of inert atmosphere. This work highlights three advantages of electrochemistry in flow, which is (i) a supporting electrolyte-free reaction, (ii) an easy scale-up of the reaction without the need for a larger reactor and, (iii) the important and effective impact of having a good mixing of the reaction mixture, which can be achieved effectively with the use of flow systems. This clearly improves the reported methods for the synthesis of benzothiazoles.

20.
Pain Med ; 19(1): 130-141, 2018 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-28472393

RESUMEN

Objectives: Percutaneous radiofrequency ablation (RFA) of the gasserian ganglion through the foramen ovale and the glossopharyngeal nerve at the jugular foramen is a classical approach to treating trigeminal neuralgia (TN) and glossopharyngeal neuralgia (GPN), respectively. However, it can be technically challenging with serious complications. We have thus developed a novel technique utilizing C-arm and computerized tomography (CT) guidance to block TN and GPN. Our goals were to describe a three-dimensional image-based technique to improve patient comfort and to decrease procedural time associated with needle guidance. Study design: Consecutive procedures were reviewed. Setting: Academic hospital. Methods: Three patients with classical TN and GPN and 15 patients with atypical facial pain (AFP) were treated. Numeric rating scale (NRS) scores for pain at pretreatment and at one, three, and 12 months post-treatment were recorded. The primary clinical outcome (50% or more reduction in NRS) and secondary adverse clinical outcome (hematoma, facial numbness, etc.) were monitored. Results: We had a 100% technical success with respect to appropriate needle positioning. All three classical TN/GPN patients had both immediate and sustained pain relief. Complications were minimal. The 15 AFP patients, however, showed more variable results, with only five (33%) having sustained pain relief, while in the other 10 (67%) patients, we observed suboptimal response. Conclusions: We present a novel method and single-center experience with C-arm and CT-guided RFA of facial pain. Quick and accurate needle placement will help future advancements in the RFA algorithm so that more durable and consistent effects can be attained, reducing uncertainty with respect to needle placement as a confounder. The RFA procedure in our study had a satisfying effect for classical TN/GPN patients but was less successful for AFP patients, though it did mirror the results from previous studies. Limitations: This study is limited by its small sample size and nonrandomized design.


Asunto(s)
Neuralgia Facial/diagnóstico por imagen , Neuralgia Facial/cirugía , Imagenología Tridimensional/métodos , Ablación por Radiofrecuencia/métodos , Cirugía Asistida por Computador/métodos , Adulto , Anciano de 80 o más Años , Femenino , Fluoroscopía , Humanos , Masculino , Tomografía Computarizada por Rayos X , Adulto Joven
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