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1.
J Neurophysiol ; 129(1): 56-65, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-36475885

RESUMO

High-frequency repetitive transcranial magnetic stimulation (HF-rTMS) remains a promising strategy for neurorehabilitation. The stimulation intensity (SI) influences the aftereffects observed. Here, we examined whether single sessions of a 15 Hz rTMS protocol, administered at suprathreshold SI, can be safely administered to able-bodied (AB) individuals. Six right-handed men were included in this pilot study. HF-rTMS was delivered over the right M1, in 10 trains of 75 biphasic stimuli at 15 Hz, at 105-120% of the individual resting motor threshold (RMT). To assess safety, electromyography (EMG) was monitored to control for signs of spread of excitation and brief EMG burst (BEB) after stimulation. Additionally, TMS side effects questionnaires and the numeric rating scale (NRS) were administered during each session. We assessed corticospinal excitability (CSE) and motor performance changes with measures of resting (rMEP) and active (aMEP) motor evoked potential and grip strength and box and blocks test (BBT) scores, respectively. Overall, the sessions were tolerated and feasible without any pain development. However, EMG analysis during 15 Hz rTMS administration revealed increased BEB frequency with SI. Statistical models revealed an increase of CSE at rest (rMEP) but not during active muscle contraction (aMEP). No linear relationship was observed between 15 Hz rTMS SI and rMEP increase. No significant changes were highlighted for motor performance measures. Although feasible and tolerable by the AB individuals tested, the results demonstrate that when administered at suprathreshold intensities (≥ 105% RMT) the 15 Hz rTMS protocol reveals signs of persistent excitation, suggesting that safety precautions and close monitoring of participants should be performed when testing such combinations of high-intensity and high-frequency stimulation protocols. The results also give insight into the nonlinear existent relationship between the SI and HF-rTMS effects on CSE.NEW & NOTEWORTHY The results of this pilot study show the effects of a therapeutically promising 15 Hz repetitive transcranial magnetic stimulation (rTMS) protocol, administered at different suprathreshold intensities in able-bodied individuals. Although tolerable and feasible with a neuromodulatory potential, 15 Hz rTMS might result in persistent excitability that needs to be closely monitored if administered at suprathreshold stimulation intensity. These results reaffirm the importance of feasibility studies, especially in translational animal-to-human research.


Assuntos
Córtex Motor , Estimulação Magnética Transcraniana , Masculino , Humanos , Estimulação Magnética Transcraniana/efeitos adversos , Projetos Piloto , Córtex Motor/fisiologia , Eletromiografia/métodos , Potencial Evocado Motor/fisiologia
2.
Nature ; 534(7606): 231-4, 2016 06 09.
Artigo em Inglês | MEDLINE | ID: mdl-27279218

RESUMO

Fuel cells convert chemical energy directly into electrical energy with high efficiencies and environmental benefits, as compared with traditional heat engines. Yttria-stabilized zirconia is perhaps the material with the most potential as an electrolyte in solid oxide fuel cells (SOFCs), owing to its stability and near-unity ionic transference number. Although there exist materials with superior ionic conductivity, they are often limited by their ability to suppress electronic leakage when exposed to the reducing environment at the fuel interface. Such electronic leakage reduces fuel cell power output and the associated chemo-mechanical stresses can also lead to catastrophic fracture of electrolyte membranes. Here we depart from traditional electrolyte design that relies on cation substitution to sustain ionic conduction. Instead, we use a perovskite nickelate as an electrolyte with high initial ionic and electronic conductivity. Since many such oxides are also correlated electron systems, we can suppress the electronic conduction through a filling-controlled Mott transition induced by spontaneous hydrogen incorporation. Using such a nickelate as the electrolyte in free-standing membrane geometry, we demonstrate a low-temperature micro-fabricated SOFC with high performance. The ionic conductivity of the nickelate perovskite is comparable to the best-performing solid electrolytes in the same temperature range, with a very low activation energy. The results present a design strategy for high-performance materials exhibiting emergent properties arising from strong electron correlations.

3.
Appl Opt ; 57(1): A229-A234, 2018 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-29328150

RESUMO

We propose a technique in which intensity images are reconstructed from a digital hologram to provide inputs for the transport-of-intensity equation for unwrapped phase recovery. By doing this, we avoid shifting of the sample or the camera in the experiment, a method commonly employed while using the method of transport-of-intensity equation for phase retrieval. Computer simulations as well as experimental results have been demonstrated to verify the effectiveness of the proposed idea. The underlying numerical technique can also be viewed as an alternative to existing phase-unwrapping algorithms.

4.
Small ; 13(47)2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-29094479

RESUMO

Stimuli-responsive porous polymer materials have promising biomedical application due to their ability to trap and release biomacromolecules. In this work, a class of highly porous electrospun fibers is designed using polylactide as the polymer matrix and poly(ethylene oxide) as a porogen. Carbon nanotubes (CNTs) with different concentrations are further impregnated onto the fibers to achieve self-sealing functionality induced by photothermal conversion upon light irradiation. The fibers with 0.4 mg mL-1 of CNTs exhibit the optimum encapsulation efficiency of model biomacromolecules such as dextran, bovine serum albumin, and nucleic acids, although their photothermal conversion ability is slightly lower than the fibers with 0.8 mg mL-1 of CNTs. Interestingly, reversible reopening of the surface pores is accomplished with the degradation of PLA, affording a further possibility for sustained release of biomacromolecules after encapsulation. Effects of CNT loading on fiber morphology, structure, thermal/mechanical properties, degradation, and cell viability are also investigated. This novel class of porous electrospun fibers with self-sealing capability has great potential to serve as an enabling strategy for trapping/release of biomacromolecules with promising applications in, for example, preventing inflammatory diseases by scavenging cytokines from interstitial body fluids.


Assuntos
Substâncias Macromoleculares/química , Nanotecnologia/métodos , Nanotubos de Carbono/química , Animais , Proliferação de Células , Sobrevivência Celular , Fluoresceína/química , Interações Hidrofóbicas e Hidrofílicas , Mioblastos/citologia , Nanotubos de Carbono/ultraestrutura , Poliésteres/química , Polietilenoglicóis/química , Porosidade , Rodaminas/química , Soroalbumina Bovina/química , Resistência à Tração
5.
Int Orthop ; 41(2): 323-332, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27591770

RESUMO

PURPOSE: Beginners usually need increased punctures and dozens of fluoroscopy in learning transforamimal percutaneous endoscopic lumbar discectomy (tPELD). Navigator-assisted spinal surgery (NASS) is a novel technique that could induce a definite trajectory. The retrospective study aimed to investigate the impact of a definite trajectory on the learning curve of tPELD. METHODS: A total of 120 patients with symptomatic lumbar disc herniation who received tPELD between 2012 and 2014. Patients receiving tPELD with NASS technique by one surgeon were regarded as group A, and those receiving conventional methods by another surgeon were regarded as group B. Each group was divided into three subgroups (case 1-20, case 21-40, case 41-60). RESULTS: The fluoroscopy times were 22.62 ± 3.80 in group A and 34.32 ± 4.78 in group B (P < 0.001). The pre-operative location time was 3.56 ± 0.60 minutes in group A and 5.49 ± 1.48 minutes in group B (P < 0.001). The puncture-channel time was 21.85 ± 4.31 minutes in group A and 34.20 ± 8.88 minutes in group B (P < 0.001). The operation time was 84.62 ± 9.20 minutes in group A and 101.97 ± 14.92 minutes in group B (P < 0.001), and the learning curve of tPELD in group A was steeper than that in group B. No significant differences were detected in patient-reported outcomes, hospital stay, patient satisfaction, and complication rate between the two groups (p > 0.05). CONCLUSIONS: Definite trajectory significantly reduced the operation time, preoperative location time, puncture-channel time, and fluoroscopy times of tPELD by beginners, and thus reshaped the learning curve of tPELD and minimized the radiation exposure.


Assuntos
Discotomia Percutânea/métodos , Deslocamento do Disco Intervertebral/cirurgia , Curva de Aprendizado , Vértebras Lombares/cirurgia , Adulto , Discotomia Percutânea/estatística & dados numéricos , Endoscopia/métodos , Endoscopia/estatística & dados numéricos , Feminino , Fluoroscopia/estatística & dados numéricos , Humanos , Tempo de Internação/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Duração da Cirurgia , Estudos Retrospectivos
6.
Neurosurg Rev ; 39(3): 385-91, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26686852

RESUMO

Although application of intraoperative computer navigation technique had been integrated into placement of pedicle screws (PSs) in thoracic fusion for years, its security and practicability remain controversial. The aim of this study is to evaluate the accuracy, the operative time consumption, the amount of intraoperative blood loss, time of pedicle insertion and the incidence of complications of thoracic pedicle screw placement in patients with thoracic diseases such as scoliosis and kyphosis. Pubmed, Web of Knowledge, and Google scholar were searched to identify comparative studies of thoracic pedicle screw placement between intraoperative computer navigation and fluoroscopy-guided navigation. Outcomes of malposition rate, operative time consumption, insertion time, intraoperative blood loss, and the incidence of complications are evaluated. Fourteen articles including 1723 patients and 9019 PSs were identified matching inclusion criteria. The malposition rate was lower (RR: 0.33, 95 % CI: 0.28-0.38, P < 0.01) in computer navigation group than that in fluoroscopy-guided navigation group; the operative time was significantly longer [weighted mean difference (WMD) = 23.66, 95 % CI: 14.74-32.57, P < 0.01] in computer navigation group than that in fluoroscopy-guided navigation group. The time of insertion was shorter (WMD = -1.88, 95 % CI: -2.25- -1.52, P < 0.01) in computer navigation group than that in fluoroscopy-guided navigation group. The incidence of complications was lower (RR = 0. 23, 95 % CI: 0.12-0.46, P < 0.01) in computer navigation group than that in the other group. The intraoperative blood loss was fewer (WMD = -167.49, 95 % CI: -266.39- -68.58, P < 0.01) in computer navigation group than that in the other. In conclusion, the meta-analysis of thoracic pedicle screw placement studies clearly demonstrated lower malposition rate, less intraoperative blood loss, and fewer complications when using computer navigation. This result provides strong evidence that computer technology could be safer and more reliable than fluoroscopy-guided navigation.


Assuntos
Fluoroscopia , Vértebras Lombares/cirurgia , Parafusos Pediculares , Cirurgia Assistida por Computador , Vértebras Torácicas/cirurgia , Humanos , Fusão Vertebral/métodos , Cirurgia Assistida por Computador/métodos , Vértebras Torácicas/patologia
7.
Ergonomics ; 59(11): 1453-1461, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27046745

RESUMO

This cross-sectional study aimed to identify gender differences in the cervical postures when young adults were using mobile phones, as well as the correlations between the postures and the digital devices use (computer and mobile phone). Questionnaires regarding the habits of computer and mobile phone use were administrated to 429 subjects aged from 17 to 33 years old (19.75 ± 2.58 years old). Subjects were instructed to stand habitually and use a mobile phone as in daily life; the sagittal head and cervical postures were measured by head flexion, neck flexion angle and gaze angle. Male participants had a significantly larger head flexion angle (96.41° ± 12.23° vs. 93.57° ± 12.62°, p  =  0.018) and neck flexion angle (51.92°  ±  9.55° vs. 47.09° ± 9.45°, p  <  0.001) than females. There were significant differences in head (F  =  3.62, p  =  0.014) and neck flexion (F  =  3.99, p  =  0.009) between different amounts of computer use. Practitioner Summary: We investigated possible gender differences in head and neck postures of young adults using mobile phones, as well as the potential correlations between these postures and digital device use. We found that males displayed larger head and neck flexion angles than females, which were associated with the amount of computer use.


Assuntos
Computadores/estatística & dados numéricos , Pescoço , Postura , Smartphone/estatística & dados numéricos , Adolescente , Adulto , Telefone Celular/estatística & dados numéricos , Computadores de Mão/estatística & dados numéricos , Estudos Transversais , Feminino , Humanos , Masculino , Amplitude de Movimento Articular , Fatores Sexuais , Coluna Vertebral , Adulto Jovem
8.
Eur Spine J ; 24(8): 1640-8, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26002354

RESUMO

PURPOSE: To compare the clinical and radiological outcomes of unilateral versus bilateral instrumented in two-level degenerative lumbar diseases after minimally invasive transforaminal lumbar interbody fusion (MITLIF). METHODS: We conducted a prospective cohort study of 74 patients, who underwent unilateral or bilateral instrumented in two-level MITLIF for degenerative lumbar diseases from May 2010 to June 2012. There were 35 patients in group A undergoing unilateral pedicle screw fixation and 39 patients in group B undergoing bilateral pedicle screw fixation. Demographic data and clinical characteristics were compared between the two groups before surgery. Perioperative data, clinical and radiological outcomes of the two groups were also compared. RESULTS: The mean follow-up period was 32.1 ± 7.5 months for group A and 31.7 ± 8.0 months for group B (p > 0.05). Group A required a significantly shorter operating time, lower implant costs and less intraoperative blood loss and X-ray exposure time than group B (p < 0.01). However, no statistical differences were identified in the amount of transfusion and postoperative hospital stay between the two groups (p > 0.05). Clinical outcomes assessed by visual analog scores for back and leg pain (VAS-BP and VAS-LP, respectively) and Oswestry Disability Index (ODI) improved significantly in both groups after surgery, and no significant differences existed between the two groups at each postoperative follow-up (p > 0.05). There were significant differences within groups for Cobb angles of the whole lumbar [Cobb (a)] and the whole lumbar lordosis at each time point before and after surgery (p < 0.05). No significant differences existed between groups in relation to Cobb (a), Cobb angle of the fused segments, lumbar lordosis and the segmental lordosis at any time point before and after surgery (p > 0.05). There were no significant differences in fusion rate and total complication rate between the two groups (p > 0.05). CONCLUSIONS: Unilateral instrumentation after two-level MITLIF provided similar clinical and radiological outcomes to bilateral fixation in two-level degenerative lumbar diseases. Compared with bilateral fixation, unilateral fixation shortens operation time, reduces intra-operative blood loss and X-ray exposure time, and saves medical expenses with similar postoperative hospital stay and complication rate.


Assuntos
Vértebras Lombares/cirurgia , Parafusos Pediculares , Doenças da Coluna Vertebral/cirurgia , Fusão Vertebral/métodos , Adulto , Idoso , Estudos de Coortes , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fusão Vertebral/instrumentação , Resultado do Tratamento
9.
Eur Spine J ; 24(12): 2892-8, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26206292

RESUMO

PURPOSE: With the dramatic growth of mobile phone usage, concerns have been raised with regard to the adverse health effects of mobile phone on spinal posture. The aim of this study was to determine the head and cervical postures by photogrammetry when viewing the mobile phone screen, compared with those in neutral standing posture. METHODS: A total of 186 subjects (81 females and 105 males) aged from 17 to 31 years old participated in this study. Subjects were instructed to stand neutrally and using mobile phone as in daily life. Using a photographic method, the sagittal head and cervical postures were assessed by head tilt angle, neck tilt angle, forward head shift and gaze angle. RESULTS: The photographic method showed a high intra-rater and inter-rater reliability in measuring the sagittal posture of cervical spine and gaze angle (ICCs ranged from 0.80 to 0.99). When looking at mobile phone, the head tilt angle significantly increased (from 74.55° to 95.22°, p = 0.000) and the neck angle decreased (from 54.68° to 38.77°, p = 0.000). The forward head posture was also confirmed by the significantly increased head shift (from 10.90 to 13.85 cm, p = 0.000). The posture assumed in mobile phone use was significantly correlated with neutral posture (p < 0.05). Males displayed a more forward head posture than females (p < 0.05). The head tilt angle was positively correlated with the gaze angle (r = 0.616, p = 0.000), while the neck tilt angle was negatively correlated with the gaze angle (r = -0.628, p = 0.000). CONCLUSIONS: Photogrammetry is a reliable, quantitative method to evaluate the head and cervical posture during mobile phone use. Compared to neutral standing, subjects display a more forward head posture when viewing the mobile phone screen, which is correlated with neutral posture, gaze angle and gender. Future studies will be needed to investigate a dose-response relationship between mobile phone use and assumed posture.


Assuntos
Telefone Celular , Vértebras Cervicais/fisiologia , Cabeça/fisiologia , Pescoço/fisiologia , Fotografação , Postura/fisiologia , Adolescente , Adulto , Feminino , Humanos , Masculino , Fotogrametria , Projetos Piloto , Reprodutibilidade dos Testes , Adulto Jovem
10.
J Spinal Disord Tech ; 28(2): E78-84, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25093650

RESUMO

STUDY DESIGN: A magnetic resonance neurography (MRN)-based morphometric analysis of the working zone for posterolateral endoscopic lumbar discectomy (PELD) procedures on 32 health volunteers. OBJECTIVE: The purpose is to utilize MRN as a noninvasive evaluation of the Kambin's working zone, and further to analyze operative safety of the PELD procedures. SUMMARY OF BACKGROUND DATA: Intraoperative nerve root injuries of PELD procedures occur relative to the Kambin's triangular working zone, which has been described previously based on formalin-fixed cadaver studies. However, the investigation in living individuals is not known. Thus, it is necessary to evaluate the dimensions of the working zone on both coronal and sagittal plane by radiologic assessments. MATERIALS AND METHODS: MRN images of 32 health volunteers (average age 26.8 y; 18 men, 14 women) were analyzed from L1-L2 to L5-S1. On the coronal plane, we measured the distance from the superior endplate to the nerve root exiting from the dura (distance a), the distance from lateral aspect of the dura to the medial aspect of the nerve root along the superior endplate (distance b), and the angle between the nerve root and plane of the corresponding disk (angle α). On the transversal plane, the vertical distance from the upper facet surface to the exiting nerve root at the lower/upper disk margin level (distance c/d) was also measured. RESULTS: On the coronal plane, distance a was 16.69±5.07 mm (range, 6.60-26.10 mm), distance b was 13.64±2.52 mm (range, 9.30-21.20 mm), angle α was 55.45±7.14 degrees (range, 40.00-73.00 degrees). Distance c on the transversal plane was 5.01±2.66 mm (range, 1.30-13.10 mm) and distance d was 1.99±1.26 mm (range, 0.70-7.80 mm). All these measurements increased as the spine level went down. CONCLUSIONS: The study indicated that MRN was a feasible noninvasive tool to evaluate the anatomic dimensions in the Kambin's working zone. Before PELD, radiologic measurements of this working zone were recommended to perform a safer procedure.


Assuntos
Discotomia/métodos , Endoscopia/métodos , Vértebras Lombares/patologia , Vértebras Lombares/cirurgia , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Procedimentos Ortopédicos/métodos , Adulto , Cadáver , Dura-Máter/patologia , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Neuroimagem , Raízes Nervosas Espinhais/patologia , Raízes Nervosas Espinhais/cirurgia , Adulto Jovem
11.
J Spinal Disord Tech ; 28(3): E173-80, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25353207

RESUMO

STUDY DESIGN: A prospective study. OBJECTIVE: To further investigate the implication of our surface locator and intradermal locator to reduce the radiation exposure to surgeons in minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) surgery. SUMMARY OF BACKGROUND DATA: Our previous studies published in the journal have introduced our novel spinal locators effectively minimizing fluoroscopic time during minimally invasive spinal surgery. METHODS: Twenty patients underwent MIS-TLIF surgery with G-arm fluoroscopy from January 2013 to June 2013. There were 10 patients in group A who underwent standard MIS-TLIF using our spinal locators, and the other 10 in group B underwent conventional MIS-TLIF without spinal locators. The radiation dosages to the arm, the finger, the whole body, thyroid gland, gonad gland, and the eye of the surgeon were measured by thermoluminescence badges for both groups. RESULTS: All 20 patients (9 male, 11 female), aged from 48 to 77 years old, successfully underwent the surgery. The operation time was 171.20±10.28 minutes for group A and 189.80±11.99 minutes for group B. The fluoroscopy time was 49.60±7.32 seconds for group A and 68.40±7.62 seconds for group B, hence a reduction of 27.49% was observed. There was no correlation between operation time and exposure time for group A or group B. The radiation reduction was 35.28% for the arm, 17.95% for the finger, 45.23% for the whole body, 53.62% for the thyroid gland (protected), 52.44% for the thyroid gland (unprotected), 44% for gonad gland (protected), 36.42% for the gonad gland (unprotected), 59.42% for the eye (protected), and 59.70% for the eye (unprotected). CONCLUSION: The study indicated that radiation exposure to the surgeon would be effectively reduced in MIS-TLIF using our surface locator and intradermal locator, and it could be another practical choice for radiation-minimizing strategy.


Assuntos
Fluoroscopia/instrumentação , Vértebras Lombares/cirurgia , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Exposição Ocupacional/prevenção & controle , Lesões por Radiação/prevenção & controle , Fusão Vertebral/métodos , Cirurgiões , Idoso , Feminino , Fluoroscopia/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Duração da Cirurgia , Estudos Prospectivos , Doses de Radiação , Monitoramento de Radiação , Proteção Radiológica
12.
Int Orthop ; 38(4): 817-24, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24240484

RESUMO

PURPOSE: The purpose of this study was to compare the clinical and radiological outcomes of minimally invasive versus open transforaminal lumbar interbody fusion in two-level degenerative lumbar disease. METHODS: We conducted a prospective cohort study of 82 patients, who underwent two-level minimally invasive or open transforaminal lumbar interbody fusion (TLIF) from March 2010 to December 2011. Forty-four patients underwent minimally invasive transforaminal lumbar interbody fusion (MITLIF) (group A) and 38 patients underwent the traditional open TLIF (group B). Demographic data and clinical characteristics were comparable between the two groups before surgery (p > 0.05). Peri-operative data, clinical and radiological outcomes between the two groups were compared. RESULTS: The mean follow-up period was 20.6 ± 4.5 months for group A and 20.0 ± 3.3 months for group B (p > 0.05). No significant difference existed in operating time between the two group (p > 0.05). X-ray exposure time was significantly longer for MITLIF compared to open cases. Intra-operative blood loss and duration of postoperatively hospital stay of group A were significantly superior to those of group B (p < 0.05). On postoperative day three, MITLIF patients had significantly less pain compared to patients with the open procedure. No statistical difference existed in pre-operative and latest VAS value of back pain (VAS-BP) and leg pain (VAS-LP), pre-operative and latest ODI between the two groups. The fusion rate of the two groups was similar (p < 0.05). Complications included small dural tear, superficial wound infection and overlong screws. When comparing the total complications, no significant difference existed between the groups (p > 0.05). CONCLUSIONS: MITLIF offers several potential advantages including postoperative back pain and leg pain, intra-operative blood loss, transfusion and duration of hospital stay postoperatively in treating two-level lumbar degenerative disease. However, it required much more radiation exposure.


Assuntos
Degeneração do Disco Intervertebral , Vértebras Lombares , Fusão Vertebral/métodos , Idoso , Perda Sanguínea Cirúrgica/estatística & dados numéricos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Procedimentos Cirúrgicos Minimamente Invasivos , Medição da Dor , Dor Pós-Operatória/prevenção & controle , Tomografia Computadorizada por Raios X
13.
ChemSusChem ; : e202401533, 2024 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-39370892

RESUMO

Carbon dioxide (CO2) capture is a crucial negative-emission technology for the mitigation of climate change and global warming. The urgent need of combating climate change motivates the research and development of economical, effective and environmentally benign processes for CO2 capture. Herein, we design and report a flow cell for the CO2 capture from air or flue gas in a precipitate-free and closed-loop manner. No ion-exchange membrane is used in the electrolyser. The water electrolysis produces acidic solution near the anode and alkaline solution near the cathode, while generating valuable hydrogen and oxygen byproducts. The dilute CO2 in air or flue gas is captured by the alkaline solution, which is then mixed with the acidic solution to release the concentrated CO2. The process operates in a cyclic manner as driven by the water electrolysis and the mechanical pumping. No precipitation of calcium carbonate is involved for fixing CO2, which may simplify the separation process and minimizing the materials loss. The simple process enabled by electrochemical pH gradient shows promise for efficient CO2 capture on both small and large scales.

14.
J Headache Pain ; 14: 7, 2013 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-23565873

RESUMO

Randomized clinical trials (RCT) assessing the efficacy and tolerability of triptans compared with placebo as short-term prophylaxis of menstrual migraine (MM) were systematically reviewed in this study. Triptans, which interfere with the pathogenesis of migraine and are effective in relieving associated neurovegetative symptoms, have been extensively proposed for prevention of menstrual migraine attacks. We searched Cochrane CENTRAL, MEDLINE and EMBASE for randomized, double-blind, placebo-controlled trials on triptans for MM until 1 Oct, 2012. A total of six RCTs were identified. Two authors independently assessed trial's quality and extracted data. Numbers of participants free from MM per perimenstrual period (PMP), requiring rescue medication, suffering from headache-associated symptoms and experiencing adverse events in treatment and control groups were used to calculate relative risk (RR) and number needed to treat (NNT) with their corresponding 95% confidence interval (CI). A total of 633 participants received frovatriptan 2.5 mg QD, 584 received frovatriptan 2.5 mg BID, 392 received naratriptan 1 mg BID, 70 received naratriptan 2.5 mg BID, 80 received zolmitriptan 2.5 mg BID, 83 received zolmitriptan 2.5 mg TID and 1104 received placebo. Overall, triptans is an effective, short-term, prophylactic treatment of choice for MM. Considering MM frequency, severity and adverse events, frovatriptan 2.5 mg BID and zolmitriptan 2.5 mg TID tend to be the preferred regimens.


Assuntos
Ciclo Menstrual/fisiologia , Transtornos de Enxaqueca/tratamento farmacológico , Transtornos de Enxaqueca/etiologia , Triptaminas/uso terapêutico , Método Duplo-Cego , Feminino , Humanos , Menstruação/fisiologia , Ensaios Clínicos Controlados Aleatórios como Assunto
15.
J Headache Pain ; 14: 72, 2013 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-23964790

RESUMO

Trigeminal neuralgia is a common disorder caused mainly by compression of the trigeminal nerve root by an overlying blood vessel. Pharmacotherapy and surgery are ineffective or unsuitable in many patients. Therefore, other therapeutic modalities have been tried, including injection of botulinum toxin type A (BTX-A). This study aims to systematically review the therapeutic efficacy and safety of BTX-A in trigeminal neuralgia. PubMed, EMBASE, Cochrane Library Clinical Trials and Web of Science from January 1966 to March 2013 were searched with the terms of "botulinum toxin" AND "trigeminal neuralgia", and references of related articles were traced. Data on the efficacy and safety of BTX-A in this disorder were extracted and analyzed by at least 2 reviewers. Data for individual studies were reported, and pooled data were analyzed if appropriate. Five prospective studies and one double-blind, randomized, placebo-controlled study were identified. Response was achieved in approximately 70-100% of patients, and the mean pain intensity and frequency were reduced by approximately 60-100% at 4 weeks after treatment in most studies. Major adverse events were not reported. Available studies show BTX-A may be effective in treatment of trigeminal neuralgia. However, well-designed randomized, controlled, double-blinded trial is still lacking. Future BTX-A treatment studies on optimal dose, duration of the therapeutic efficacy, common AEs, and the time and indications for repeat injection would be promising.


Assuntos
Toxinas Botulínicas Tipo A/efeitos adversos , Toxinas Botulínicas Tipo A/uso terapêutico , Neuralgia do Trigêmeo/tratamento farmacológico , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto
16.
Sci Transl Med ; 15(677): eabq6885, 2023 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-36599003

RESUMO

Facilitating axon regeneration in the injured central nervous system remains a challenging task. RAF-MAP2K signaling plays a key role in axon elongation during nervous system development. Here, we show that conditional expression of a constitutively kinase-activated BRAF in mature corticospinal neurons elicited the expression of a set of transcription factors previously implicated in the regeneration of zebrafish retinal ganglion cell axons and promoted regeneration and sprouting of corticospinal tract (CST) axons after spinal cord injury in mice. Newly sprouting axon collaterals formed synaptic connections with spinal interneurons, resulting in improved recovery of motor function. Noninvasive suprathreshold high-frequency repetitive transcranial magnetic stimulation (HF-rTMS) activated the BRAF canonical downstream effectors MAP2K1/2 and modulated the expression of a set of regeneration-related transcription factors in a pattern consistent with that induced by BRAF activation. HF-rTMS enabled CST axon regeneration and sprouting, which was abolished in MAP2K1/2 conditional null mice. These data collectively demonstrate a central role of MAP2K signaling in augmenting the growth capacity of mature corticospinal neurons and suggest that HF-rTMS might have potential for treating spinal cord injury by modulating MAP2K signaling.


Assuntos
Axônios , Traumatismos da Medula Espinal , Animais , Camundongos , Axônios/fisiologia , Engenharia Genética , Regeneração Nervosa/fisiologia , Proteínas Proto-Oncogênicas B-raf/metabolismo , Tratos Piramidais/metabolismo , Recuperação de Função Fisiológica/fisiologia , Traumatismos da Medula Espinal/genética , Traumatismos da Medula Espinal/terapia , Traumatismos da Medula Espinal/metabolismo , Estimulação Magnética Transcraniana , Fatores de Transcrição/metabolismo , Peixe-Zebra
17.
J Healthc Eng ; 2022: 8094385, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35126948

RESUMO

BACKGROUND: miR-206 was reported to be a tumor suppressor in bladder cancer. In this study, we explore the expression and function of miR-206 in endometriosis (EM). METHODS: 40 EM patients undergoing total hysterectomy were selected as the experimental group. RT-qPCR assay was adopted to detect the expression of MALAT1 and miR-206 in EM. Cell proliferation was detected by EdU incorporation and colony formation assay. Cell migration and invasion viability of ESCs were examined by transwell assay and wound healing assay. Flow cytometry was carried out to assess cell apoptosis of ESCs. The protein expressions of Bcl-2 and Bax were examined by western blot assay. The relationship between miR-206 and MALAT1 was verified by the dual-luciferase reporter assay and RNA pull-down assay. RESULTS: In this work, miR-206 was found to be downregulated in EM. Functional experiments displayed that miR-206 mimic repressed cell proliferation, migration, and invasion of ESCs and promoted cell apoptosis of ESCs. Furthermore, miR-206 mimic reduced the expression of Bcl-2 but enhanced the expression of Bax. MALAT1 was found to be upregulated in EM. Furthermore, MALAT1 was indicated to be a target of miR-206. Additionally, MALAT1 was found to alleviate the influence of miR-206 on cell progression of ESCs. Furthermore, miR-206 inhibited tumor growth in vivo. CONCLUSION: This study indicated that miR-206 inhibited cell progression by regulating MALAT1 in EM. Hence, miR-206 was suggested to be a possible target for EM treatment.


Assuntos
Endometriose , MicroRNAs , RNA Longo não Codificante , Endometriose/genética , Endometriose/metabolismo , Feminino , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Células Estromais/metabolismo , Proteína X Associada a bcl-2/genética , Proteína X Associada a bcl-2/metabolismo
18.
Annu Int Conf IEEE Eng Med Biol Soc ; 2022: 2385-2389, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-36085970

RESUMO

Since its first use in spinal cord injury (SCI) in the early 2000s [1], high-frequency repetitive transcranial magnetic stimulation (HF-rTMS) demonstrated a capacity to modulate corticospinal excitability (CSE) and motor performance. Studies focused on individuals with incomplete SCI. Here, we examined the feasibility of a 15-day therapeutic stimulation protocol combining HF-rTMS with task-specific motor training targeting the weaker hand in an individual with early chronic complete SCI. In this case report, we present evidence of progressive increase of CSE at rest and during muscle activation, and decreased cortical inhibition, associated with a trend toward improvement in pinch function of the weaker hand. These promising findings need to be confirmed in a larger population. Clinical Relevance- These preliminary results are promising and demonstrate the importance of a large number of training session repetitions to induce consistent changes relevant to the recovery after a complete SCI.


Assuntos
Traumatismos da Medula Espinal , Estimulação Magnética Transcraniana , Mãos , Humanos , Estimulação Magnética Transcraniana/métodos
19.
ChemSusChem ; 14(21): 4697-4707, 2021 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-34467662

RESUMO

The Haber-Bosch process for ammonia (NH3 ) production in industry relies on high temperature and high pressure and is therefore highly energy intensive. In addition, the activity of the solid transition metal-based catalysts used is typically limited by the scaling relation between activation barrier for N2 dissociation and nitrogen-binding energy. Here, an innovative Li-based loop in a liquid alloy-salt catalytic system for ambient-pressure NH3 synthesis from N2 and H2 was developed. The looping process consisted of three reaction steps taking place simultaneously. The first step was the nitrogen fixation by Li in the liquid Li-Sn alloy to form lithium nitride (Li3 N), which floated up and dissolved into the molten salt. The second step was the hydrogenation of the Li3 N to produce NH3 and lithium hydride (LiH) in the molten salt. The third step was the decomposition of the LiH to regenerate Li in the presence of Sn. An average NH3 yield rate of 0.025 µg s-1 was achieved in an 81 h test at 510 °C and ambient pressure. The floating and dissolution of Li3 N realized in the liquid catalytic system enabled circumventing the scaling relation exerted on Li, and the remarkable properties of liquid alloy and molten salt offered extraordinary advantages for NH3 synthesis at ambient pressure.

20.
mBio ; 11(3)2020 06 09.
Artigo em Inglês | MEDLINE | ID: mdl-32518187

RESUMO

Group A Streptococcus (GAS), one of the most common extracellular pathogens, has been reported to invade epithelial and endothelial cells. Our results reveal that M1 GAS strain SF370 can be effectively eliminated by respiratory epithelial cells. Emerging evidence indicates that autophagy is an important strategy for nonphagocytes to eliminate intracellular bacteria. Upon pathogen recognition, cell surface receptors can directly trigger autophagy, which is a critical step in controlling infection. However, the mechanisms of how cells sense invading bacteria and use this information specifically to trigger autophagy remain unclear. In this study, we stimulated cells and infected mice with M and FbaA mutants of M1 GAS strain SF370 or with purified M and FbaA proteins (two critical surface structural proteins of GAS), and found that only FbaA protein was involved in autophagy induction. Furthermore, the FbaA protein induced autophagy independent of common pattern recognition receptors (such as Toll-like receptors); rather, it relies on binding to integrin α5ß1 expressed on the cell surface, which is mediated by extracellular matrix protein fibronectin (Fn). The FbaA-Fn-integrin α5ß1 complex activates Beclin-1 through the mTOR-ULK1-Beclin-1 pathway, which enables the Beclin-1/Vps34 complex to recruit Rab7 and, ultimately, to promote the formation of autophagosomes. By knocking down integrin α5ß1, Fn, Atg5, Beclin-1, and ULK1 in Hep2 cells and deleting Atg5 or integrin α5ß1 in mice, we reveal a novel role for integrin α5ß1 in inducing autophagy. Our study demonstrates that integrin α5ß1, through interacting with pathogen components, initiates effective host innate immunity against invading intracellular pathogens.IMPORTANCE Autophagy is generally considered a strategy used by the innate immune system to eliminate invasive pathogens through capturing and transferring them to lysosomes. Currently, researchers pay more attention to how virulence factors secreted by GAS regulate the autophagic process. Here, we provide the first evidence that the structural protein FbaA of M1 GAS strain SF370 is a potent inducer of autophagy in epithelial cells. Furthermore, we demonstrate that integrin α5ß1 in epithelial cells in vitro and in vivo acts as a receptor to initiate the signaling for inducing autophagy by binding to FbaA of M1 GAS strain SF370 via Fn. Our study reveals the underlying mechanisms by which pathogens induce Fn-integrin α5ß1 to trigger autophagy in a conserved pattern in epithelial cells.


Assuntos
Autofagia , Proteínas de Bactérias/metabolismo , Células Epiteliais/microbiologia , Fibronectinas/metabolismo , Integrina alfa5beta1/metabolismo , Streptococcus pyogenes/metabolismo , Animais , Linhagem Celular , Feminino , Fibronectinas/genética , Glicoproteínas/metabolismo , Interações entre Hospedeiro e Microrganismos , Humanos , Imunidade Inata , Espaço Intracelular/microbiologia , Pulmão/microbiologia , Camundongos , Camundongos Endogâmicos BALB C , Infecções Estreptocócicas/microbiologia , Infecções Estreptocócicas/fisiopatologia , Streptococcus pyogenes/genética
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