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1.
Vaccines (Basel) ; 9(12)2021 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-34960194

RESUMEN

Vaccination is the most effective preventive measure of COVID-19 available at present, but its success depends on the global accessibility of vaccines and the willingness of people to be vaccinated. As the vaccination rollouts are increasing worldwide, it is important to assess public perception and willingness towards vaccination, so that the aim of mass vaccination will be successful. This study aimed to understand public perception towards COVID-19 vaccines and their willingness to get vaccinated in Nepal. This cross-sectional online survey was conducted among 1196 residents of Nepal in August 2021; most of the participants of this online survey were young adults (18-47 years) with university-level education. A total of 64.5% (771/1196) of the participants perceived COVID-19 vaccines to be safe and risk-free, while 68.6% (820/1196) agreed that vaccination would be efficient in the fight against this pandemic. Most of the participants (841/1196, 70.3%) disagreed that people are getting COVID-19 vaccines easily in Nepal, while they agree with the prioritization of older adults and healthcare workers for vaccination. A total of 61.1% (731/1196) of the participants had received at least one dose of the vaccine. Among the unvaccinated, 93.3% (434/465) were willing to get vaccinated when their turn came. The higher confidence of younger adults in vaccines and the vaccination process is encouraging, as that can help educate others who are hesitant or are not positive towards the idea of receiving vaccines. Dissemination of correct and current information, acquisition of enough doses of vaccines, and equitable distribution of vaccines will be required to achieve successful completion of the COVID-19 vaccination campaign in Nepal.

2.
Depress Res Treat ; 2021: 7495141, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33628501

RESUMEN

This community-based study is aimed at finding out the prevalence of depression, and its correlates among adolescents of rural Nepal. Data were collected among adolescents after multistage stratified proportionate random sampling by using the Patient Health Questionnaire (PHQ-9) to assess the depression among adolescent. Chi-square test and logistic regression model were applied. The prevalence of depression was found to be 27%. Adolescents who were not satisfied with their academic performance were 2.4 times more likely to have the risk of depression (AOR = 2.417, CI: 1.097-5.326). Likewise, tobacco users were almost fourteen times (AOR = 13.858, CI: 2.090-91.90), who intended to harm themselves were two times (AOR = 2.323, CI: 1.078-5.005), sleep deprivation were fifteen folds (AOR = 14.911, CI: 7.376-30.145), often scolded by their parents was almost three times (AOR = 2.931, CI: 1.195-7.436), and having poor relationship with friends were 2.4 times more likely (AOR = 2.371, CI: 1.078-5.215) of having depression. Sleep deprivation has a long-term negative impact on health leading depression.

3.
J Magn Reson ; 249: 72-79, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25462949

RESUMEN

An EPR membrane alignment technique was applied to measure distance and relative orientations between two spin labels on a protein oriented along the surface of the membrane. Previously we demonstrated an EPR membrane alignment technique for measuring distances and relative orientations between two spin labels using a dual TOAC-labeled integral transmembrane peptide (M2δ segment of Acetylcholine receptor) as a test system. In this study we further utilized this technique and successfully measured the distance and relative orientations between two spin labels on a membrane peripheral peptide (antimicrobial peptide magainin-2). The TOAC-labeled magainin-2 peptides were mechanically aligned using DMPC lipids on a planar quartz support, and CW-EPR spectra were recorded at specific orientations. Global analysis in combination with rigorous spectral simulation was used to simultaneously analyze data from two different sample orientations for both single- and double-labeled peptides. We measured an internitroxide distance of 15.3Šfrom a dual TOAC-labeled magainin-2 peptide at positions 8 and 14 that closely matches with the 13.3Šdistance obtained from a model of the labeled magainin peptide. In addition, the angles determining the relative orientations of the two nitroxides have been determined, and the results compare favorably with molecular modeling. This study demonstrates the utility of the technique for proteins oriented along the surface of the membrane in addition to the previous results for proteins situated within the membrane bilayer.

4.
J Phys Chem B ; 116(12): 3866-73, 2012 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-22379959

RESUMEN

A membrane alignment technique has been used to measure the distance between two TOAC nitroxide spin labels on the membrane-spanning M2δ, peptide of the nicotinic acetylcholine receptor (AChR), via CW-EPR spectroscopy. The TOAC-labeled M2δ peptides were mechanically aligned using DMPC lipids on a planar quartz support, and CW-EPR spectra were recorded at specific orientations. Global analysis in combination with rigorous spectral simulation was used to simultaneously analyze data from two different sample orientations for both single- and double-labeled peptides. We measured an internitroxide distance of 14.6 Šfrom a dual TOAC-labeled AChR M2δ peptide at positions 7 and 13 that closely matches with the 14.5 Šdistance obtained from a model of the labeled AChR M2δ peptide. In addition, the angles determining the relative orientation of the two nitroxides have been determined, and the results compare favorably with molecular modeling. The global analysis of the data from the aligned samples gives much more precise estimates of the parameters defining the geometry of the two labels than can be obtained from a randomly dispersed sample.


Asunto(s)
Óxidos N-Cíclicos/química , Dimiristoilfosfatidilcolina/química , Espectroscopía de Resonancia por Spin del Electrón , Membrana Dobles de Lípidos/química , Receptores Nicotínicos/química , Secuencia de Aminoácidos , Modelos Químicos , Datos de Secuencia Molecular , Péptidos/síntesis química , Péptidos/química
5.
Biochim Biophys Acta ; 1818(3): 645-50, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22172806

RESUMEN

Wild-type phospholamban (WT-PLB), a Ca(2+)-ATPase (SERCA) regulator in the sarcoplasmic reticulum membrane, was studied using TOAC nitroxide spin labeling, magnetically aligned bicelles, and electron paramagnetic resonance (EPR) spectroscopy to ascertain structural and dynamic information. Different structural domains of PLB (transmembrane segment: positions 42 and 45, loop region: position 20, and cytoplasmic domain: position 10) were probed with rigid TOAC spin labels to extract the transmembrane helical tilt and structural dynamic information, which is crucial for understanding the regulatory function of PLB in modulating Ca(2+)-ATPase activity. Aligned experiments indicate that the transmembrane domain of wild-type PLB has a helical tilt of 13°±4° in DMPC/DHPC bicelles. TOAC spin labels placed on the WT-PLB transmembrane domain showed highly restricted motion with more than 100ns rotational correlation time (τ(c)); whereas the loop, and the cytoplasmic regions each consists of two distinct motional dynamics: one fast component in the sub-nanosecond scale and the other component is slower dynamics in the nanosecond range.


Asunto(s)
Proteínas de Unión al Calcio/química , Membrana Dobles de Lípidos/química , Simulación de Dinámica Molecular , Óxidos N-Cíclicos/química , Espectroscopía de Resonancia por Spin del Electrón/métodos , Humanos , Magnetismo , Estructura Secundaria de Proteína , Estructura Terciaria de Proteína , Marcadores de Spin
6.
Chem Phys Lipids ; 160(2): 98-104, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19501076

RESUMEN

X-band and Q-band electron paramagnetic resonance (EPR) spectroscopic techniques were used to investigate the structure and dynamics of cholesterol containing phospholipid bicelles based upon molecular order parameters (S(mol)), orientational dependent hyperfine splittings and line shape analysis of the corresponding EPR spectra. The nitroxide spin-label 3-beta-doxyl-5-alpha-cholestane (cholestane) was incorporated into DMPC/DHPC bicelles to report the alignment of bicelles in the static magnetic field. The influence of cholesterol on aligned phospholipid bicelles in terms of ordering, the ease of alignment, phase transition temperature have been studied comparatively at X-band and Q-band. At a magnetic field of 1.25 T (Q-band), bicelles with 20 mol% cholesterol aligned at a much lower temperature (313 K), when compared to 318 K at a 0.35 T field strength for X-band, showed better hyperfine splitting values (18.29 G at X-band vs. 18.55 G at Q-band for perpendicular alignment and 8.25 G at X-band vs. 7.83 G at Q-band for the parallel alignment at 318 K) and have greater molecular order parameters (0.76 at X-band vs. 0.86 at Q-band at 318 K). Increasing cholesterol content increased the bicelle ordering, the bicelle-alignment temperature and the gel to liquid crystalline phase transition temperature. We observed that Q-band is more effective than X-band for studying aligned bicelles, because it yielded a higher ordered bicelle system for EPR spectroscopic studies.


Asunto(s)
Colesterol/química , Espectroscopía de Resonancia por Spin del Electrón/métodos , Membrana Dobles de Lípidos/química , Dimiristoilfosfatidilcolina/química , Cristales Líquidos/química , Magnetismo , Membranas Artificiales , Transición de Fase , Éteres Fosfolípidos/química , Temperatura de Transición
7.
Biochemistry ; 48(25): 5782-4, 2009 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-19476379

RESUMEN

Pulsed electron double resonance (PELDOR)/double electron-electron resonance (DEER) spectroscopy is a very powerful structural biology tool in which the dipolar coupling between two unpaired electron spins (site-directed nitroxide spin-labels) is measured. These measurements are typically conducted at X-band (9.4 GHz) microwave excitation using the four-pulse DEER sequence and can often require up to 12 h of signal averaging for biological samples (depending on the spin-label concentration). In this work, we present for the first time a substantial increase in DEER sensitivity obtained by collecting DEER spectra at Q-band (34 GHz), when compared to X-band. The huge boost in sensitivity (factor of 13) demonstrated at Q-band represents a 169-fold decrease in data collection time, reveals a greatly improved frequency spectrum and higher-quality distance data, and significantly increases sample throughput. Thus, the availability of Q-band DEER spectroscopy should have a major impact on structural biology studies using site-directed spin labeling EPR techniques.


Asunto(s)
Factores de Transcripción con Cremalleras de Leucina de Carácter Básico/química , Espectroscopía de Resonancia por Spin del Electrón/métodos , Leucina Zippers , Fragmentos de Péptidos/química , Proteínas de Saccharomyces cerevisiae/química , Secuencias de Aminoácidos , Factores de Transcripción con Cremalleras de Leucina de Carácter Básico/análisis , Espectroscopía de Resonancia por Spin del Electrón/normas , Fragmentos de Péptidos/análisis , Proteínas de Saccharomyces cerevisiae/análisis , Detección de Spin/métodos
8.
J Am Chem Soc ; 131(15): 5374-5, 2009 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-19331323

RESUMEN

A new method for measuring forces between small protein domains based on double electron-electron resonance (DEER) spectroscopy is demonstrated using a model peptide derived from the alpha-helical coiled-coil leucine zipper of yeast transcriptional activator GCN4. The equilibrium distribution of distances between two nitroxide spin labels rigidly attached to the helices of the dimer was determined by DEER and yielded a closing force of 100 +/- 10 pN between monomers, in excellent agreement with theoretical predictions.


Asunto(s)
Fenómenos Químicos , Espectroscopía de Resonancia por Spin del Electrón/métodos , Péptidos/química , Factores de Transcripción con Cremalleras de Leucina de Carácter Básico/química , Espectroscopía de Resonancia por Spin del Electrón/instrumentación , Leucina Zippers , Métodos , Multimerización de Proteína , Estructura Secundaria de Proteína , Proteínas de Saccharomyces cerevisiae/química , Marcadores de Spin
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