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991.
Vijay Kumar Rajeev Kumar Gupta Ravi Kumar Gundampati Devendra Kumar Singh Sweta Mohan Syed Hadi Hasan Manisha Malviya 《RSC advances》2018,8(2):619
The current study aims at the development of an electrochemical sensor based on a silver nanoparticle–reduced graphene oxide–polyaniline (AgNPs–rGO–PANI) nanocomposite for the sensitive and selective detection of hydrogen peroxide (H2O2). The nanocomposite was fabricated by simple in situ synthesis of PANI at the surface of rGO sheet which was followed by stirring with AEC biosynthesized AgNPs to form a nanocomposite. The AgNPs, GO, rGO, PANI, rGO–PANI, and AgNPs–rGO–PANI nanocomposite and their interaction were studied by UV-vis, FTIR, XRD, SEM, EDX and XPS analysis. AgNPs–rGO–PANI nanocomposite was loaded (0.5 mg cm−2) on a glassy carbon electrode (GCE) where the active surface area was maintained at 0.2 cm2 for investigation of the electrochemical properties. It was found that AgNPs–rGO–PANI–GCE had high sensitivity towards the reduction of H2O2 than AgNPs–rGO which occurred at −0.4 V vs. SCE due to the presence of PANI (AgNPs have direct electronic interaction with N atom of the PANI backbone) which enhanced the rate of transfer of electron during the electrochemical reduction of H2O2. The calibration plots of H2O2 electrochemical detection was established in the range of 0.01 μM to 1000 μM (R2 = 0.99) with a detection limit of 50 nM, the response time of about 5 s at a signal-to-noise ratio (S/N = 3). The sensitivity was calculated as 14.7 μA mM−1 cm−2 which indicated a significant potential as a non-enzymatic H2O2 sensor.The current study aims at the development of an electrochemical sensor based on a silver nanoparticle–reduced graphene oxide–polyaniline (AgNPs–rGO–PANI) nanocomposite for the sensitive and selective detection of hydrogen peroxide (H2O2). 相似文献
992.
Abbey Sawyer Vinicius Cavalheri Sue Jenkins Jamie Wood Nola Cecins Bhajan Singh Kylie Hill 《Sports medicine, arthroscopy, rehabilitation, therapy & technology》2018,10(1):19
Background
In people with cystic fibrosis (CF), higher exercise capacity is associated with better health-related quality of life (HRQoL), reduced risk of hospitalisation for a respiratory infection and survival. Therefore, optimisation of exercise capacity is an important treatment goal. The Australian and New Zealand clinical practice guidelines recommend that people with CF complete 30 to 60 min of moderate intensity aerobic exercise on most days of the week. This recommendation can be difficult to achieve by people with CF because of time constraints, and intolerable breathlessness and muscle fatigue during continuous exercise. In contrast, a low-volume, high intensity interval training (HIIT) program may be a more achievable and efficient training method to improve exercise capacity in people with CF.Methods
A randomised controlled trial will be undertaken. Forty people with CF (aged ≥15 years) will be randomly allocated, on a 1:1 ratio, to either the experimental or control group. Regardless of their group allocation, all participants will be asked to continue with their usual daily treatment for the study duration. Those in the experimental group will complete 8 weeks of thrice weekly HIIT on a cycle ergometer. Those in the control group will receive weekly contact with the investigators. The primary outcome of this study is exercise capacity. Secondary outcomes are HRQoL, exercise self-efficacy, feelings of anxiety, depression and enjoyment. These outcomes will be recorded at baseline (i.e. prior to randomisation) and following the 8-week intervention period. The study will also report other outcomes of the HIIT program (cardiovascular responses, symptom response, post-exercise muscle soreness and tolerance) and behaviour change techniques such as reinforcement, feedback and goal setting, used during the HIIT program.Discussion
This study will determine the effects of 8-weeks of supervised, low-volume HIIT, completed on a cycle ergometer on measures of exercise capacity, HRQoL, exercise self-efficacy, feelings of anxiety, depression and enjoyment. If effective, this type of training could be an attractive alternative to traditional continuous training because it may be more achievable and time efficient.Trial registration
Australian and New Zealand Clinical Trials Registry (ANZCTR):12617001271392 (04/09/2017).993.
Using biomimetically mineralized collagen membranes with different surface stiffness to guide regeneration of bone defects
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Yao Wang Ye Hua Qian Zhang Jie Yang Hongjie Li Ying Li Man Cao Qing Cai Xiaoping Yang Xu Zhang Changyi Li 《Journal of tissue engineering and regenerative medicine》2018,12(7):1545-1555
Because guided bone regeneration (GBR) process is pronouncedly affected by the micro‐environment in the defect, the surface stiffness of collagen membranes as a constituent part of the micro‐environment was investigated in this study. The objective of this study was to manufacture biomimetically mineralized collagen membranes with controllable surface stiffness based on biomimetic strategy and to investigate the influences of surface stiffness on GBR process. The characterization and biocompatibility of membranes were examined in vitro. The mechanical properties of membranes were evaluated on macro and micro levels using tensile test and atomic force microscope, respectively. The critical‐size cranial defect model and ectopic osteogenesis were chosen to employ their performances in vivo. The results indicated that the biomimetically mineralized collagen membranes with controllable surface stiffness were manufactured based on the biomimetic theory. The in vitro experiments showed that the mineralized collagen membrane with satisfactory surface stiffness can better promote the adhesion, proliferation, and osteogenic differentiation of mesenchymal stem cells. The membranes can perform excellently in both osteoinduction and osteoconduction, which results in effective manifestations in aspects of ectopic osteogenesis and GBR in vivo. Therefore, this biomimetically mineralized collagen membrane is a promising candidate for GBR treatment in future. 相似文献
994.
Swetlana Gautam Priyanka Singh Manjari Singh Subhadeep Roy Jitendra K. Rawat Rajnish K. Yadav Uma Devi Pushpraj S. Gupta Shubhini A. Saraf Gaurav Kaithwas 《RSC advances》2018,8(7):3512
The present study was proposed to investigate the effect of rifaximin (RFX) on methyl nitrosourea (MNU) induced mammary gland carcinoma in albino wistar rats. Animals were randomized and divided among four groups of six animals each. Group I (control 0.9% normal saline, 3 ml kg−1, p.o.); Group II (toxic control, MNU 47 mg kg−1, i.v.); Group III (RFX, 25 mg kg−1, p.o.); Group IV (RFX, 50 mg kg−1, p.o.). Toxicity was induced by single i.v. injection of MNU. MNU treatment was evident with increased alveolar bud count, differentiation score, up-regulated inflammatory enzyme markers (COX, LOX, NO and H2S) and oxidative stress markers (TBAR''s, protein carbonyl, SOD, catalase and Ach). The mammary gland surface architecture was studied using SEM, carmine staining and H&E staining. The treatment with RFX elicited noticeable restoration of the overall histological architecture in the experimental animals similar to the control. In the MNU treated toxic group, the levels of oxidative stress markers significantly increased in comparison to the control, which was subsequently restored after RFX treatment. Furthermore, RFX up regulated the levels of caspase 3 and caspase 8, when compared to the MNU treated animals. MNU associated toxicity was also ascertained, when determined for UCHL-1, COX, NF-κBp65, BAD, and BCL-xl expression, while RFX demonstrated modulation of the same.The present study was proposed to investigate the effect of rifaximin (RFX) on methyl nitrosourea (MNU) induced mammary gland carcinoma in albino wistar rats. 相似文献
995.
Datta Singh Goolaub Christopher W. Roy Eric Schrauben Dafna Sussman Davide Marini Mike Seed Christopher K. Macgowan 《Journal of cardiovascular magnetic resonance》2018,20(1):77
Purpose
To image multidimensional flow in fetuses using golden-angle radial phase contrast cardiovascular magnetic resonance (PC-CMR) with motion correction and retrospective gating.Methods
A novel PC-CMR method was developed using an ungated golden-angle radial acquisition with continuously incremented velocity encoding. Healthy subjects (n?=?5, 27?±?3 years, males) and pregnant females (n?=?5, 34?±?2 weeks gestation) were imaged at 3 T using the proposed sequence. Real-time reconstructions were first performed for retrospective motion correction and cardiac gating (using metric optimized gating, MOG). CINE reconstructions of multidimensional flow were then performed using the corrected and gated data.Results
In adults, flows obtained using the proposed method agreed strongly with those obtained using a conventionally gated Cartesian acquisition. Across the five adults, bias and limits of agreement were ??1.0 cm/s and [??5.1, 3.2] cm/s for mean velocities and???1.1 cm/s and [??6.5, 4.3] cm/s for peak velocities. Temporal correlation between corresponding waveforms was also high (R~?0.98). Calculated timing errors between MOG and pulse-gating RR intervals were low (~?20 ms). First insights into multidimensional fetal blood flows were achieved. Inter-subject consistency in fetal descending aortic flows (n =?3) was strong with an average velocity of 27.1?±?0.4 cm/s, peak systolic velocity of 70.0?±?1.8 cm/s and an intra-class correlation coefficient of 0.95 between the velocity waveforms. In one fetal case, high flow waveform reproducibility was demonstrated in the ascending aorta (R =?0.97) and main pulmonary artery (R =?0.99).Conclusion
Multidimensional PC-CMR of fetal flow was developed and validated, incorporating retrospective motion compensation and cardiac gating. Using this method, the first quantification and visualization of multidimensional fetal blood flow was achieved using CMR.996.
The experience of cancer pain is poorly understood from the perspective of African Americans, who experience higher levels of pain, more pain-related distress, and poorer function than Caucasians. Decreased perceived control over pain may play a greater role for African American patients, affecting pain-related distress and function. The purpose of this study was to add to the understanding of cancer pain and perceived control over pain in African Americans, from the patients’ perspective. This qualitative inquiry was part of a larger mixed-methods study testing an intervention to improve pain, pain-related distress, and functional status through increasing perceived control over pain. Participants were recruited from the waiting room of an urban comprehensive cancer and interviewed in their homes. Interviews with 18 adult cancer patients who self-identified as African American and reported experiencing moderate to severe pain (>4 on a 0–10 scale) within the past two weeks were included. Qualitative interviews were audiotaped, transcribed, and analyzed using a constant comparative method. Two major themes emerged from this qualitative inquiry: struggles of the chronic pain experience and benefits of perceived control over pain. Each theme contained several categories. The study unveiled the participants account of both struggles of the chronic pain experience and barriers of perceived control that can be assessed for and targeted in nursing intervention. Benefits to having perceived control over pain were also illustrated in the participants’ narratives. 相似文献
997.
998.
999.
Purpose of Review
The purpose of this review is to evaluate and describe recent and emerging treatment options for episodic migraine.Recent Findings
Recent advances have been made in better understanding the pathophysiology of migraine, which has led to further investigation of potential new pharmacologic and non-pharmacologic treatment options.Summary
A number of new medications are emerging for the acute and preventive treatment of migraine, including CGRP monoclonal antibodies, CGRP receptor antagonists, serotonin 5-HT1F agonists, and PACAP receptor monoclonal antibodies. Additionally, newer studies on existing non-invasive neuromodulation devices including transcranial magnetic stimulation, supraorbital transcutaneous nerve stimulation, and transcutaneous vagus nerve stimulation have recently received FDA approval for use in migraine. Neuromodulation devices including percutaneous mastoid electrical stimulation, non-painful remote electrical stimulation, and caloric vestibular stimulation are undergoing further investigation and have shown promising results thus far. These new developments are expected to contribute to better treatment and decreased disability in migraine.1000.