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4.
J Hazard Mater ; 403: 124003, 2021 02 05.
Artículo en Inglés | MEDLINE | ID: mdl-33265036

RESUMEN

The growing threat of terrorism has triggered an urgent need to find effective ways to improve the analysis of explosives. This will aid forensic scientists in analysing the post-blast debris, which in turn helps the law enforcement agencies to frame suitable regulations. Analysis of post-blast debris is challenging as it hosts a massive amount of complexity. There are various techniques reported till date such as mass spectrometry, gas chromatography, high-performance liquid chromatography, Fourier transform infrared spectroscopy, and Raman spectroscopy for the analysis of post-blast residues. However, none of them has been able to identify the structural composition of the explosives. The current research study focuses on identifying the structural composition of the explosives from the post-blast debris using the nuclear magnetic resonance (NMR) technology. The post-blast analytes were extracted from soil samples, cleaned by the solid phase extraction (SPE) method and were rapidly analysed by the nuclear magnetic resonance spectrometer. This paper reports the identification of nitro organic explosives such as pentaerythritol tetranitrate (PETN), trinitrotoluene (TNT) and 2,4,6-trinitrophenylmethylnitramine (tetryl) in post-blast debris by 400 MHz nuclear magnetic resonance spectrometer.

5.
Phys Rev Lett ; 121(18): 182501, 2018 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-30444390

RESUMEN

We report the first observation of the ^{108}Xe→^{104}Te→^{100}Sn α-decay chain. The α emitters, ^{108}Xe [E_{α}=4.4(2) MeV, T_{1/2}=58_{-23}^{+106} µs] and ^{104}Te [E_{α}=4.9(2) MeV, T_{1/2}<18 ns], decaying into doubly magic ^{100}Sn were produced using a fusion-evaporation reaction ^{54}Fe(^{58}Ni,4n)^{108}Xe, and identified with a recoil mass separator and an implantation-decay correlation technique. This is the first time α radioactivity has been observed to a heavy self-conjugate nucleus. A previous benchmark for study of this fundamental decay mode has been the decay of ^{212}Po into doubly magic ^{208}Pb. Enhanced proton-neutron interactions in the N=Z parent nuclei may result in superallowed α decays with reduced α-decay widths significantly greater than that for ^{212}Po. From the decay chain, we deduce that the α-reduced width for ^{108}Xe or ^{104}Te is more than a factor of 5 larger than that for ^{212}Po.

7.
Phys Rev Lett ; 120(21): 212501, 2018 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-29883168

RESUMEN

A sequence of low-energy levels in _{32}^{78}Ge_{46} has been identified with spins and parity of 2^{+}, 3^{+}, 4^{+}, 5^{+}, and 6^{+}. Decays within this band proceed strictly through ΔJ=1 transitions, unlike similar sequences in neighboring Ge and Se nuclei. Above the 2^{+} level, members of this sequence do not decay into the ground-state band. Moreover, the energy staggering of this sequence has the phase that would be expected for a γ-rigid structure. The energies and branching ratios of many of the levels are described well by shell-model calculations. However, the calculated reduced transition probabilities for the ΔJ=2 in-band transitions imply that they should have been observed, in contradiction with the experiment. Within the calculations of Davydov, Filippov, and Rostovsky for rigid-triaxial rotors with γ=30°, there are sequences of higher-spin levels connected by strong ΔJ=1 transitions which decay in the same manner as those observed experimentally, yet are calculated at too high an excitation energy.

8.
Phys Rev Lett ; 120(18): 182502, 2018 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-29775351

RESUMEN

The structure of deformed neutron-rich nuclei in the rare-earth region is of significant interest for both the astrophysics and nuclear structure fields. At present, a complete explanation for the observed peak in the elemental abundances at A∼160 eludes astrophysicists, and models depend on accurate quantities, such as masses, lifetimes, and branching ratios of deformed neutron-rich nuclei in this region. Unusual nuclear structure effects are also observed, such as the unexpectedly low energies of the first 2^{+} levels in some even-even nuclei at N=98. In order to address these issues, mass and ß-decay spectroscopy measurements of the ^{160}Eu_{97} and ^{162}Eu_{99} nuclei were performed at the Californium Rare Isotope Breeder Upgrade radioactive beam facility at Argonne National Laboratory. Evidence for a gap in the single-particle neutron energies at N=98 and for large deformation (ß_{2}∼0.3) is discussed in relation to the unusual phenomena observed at this neutron number.

9.
Phys Rev Lett ; 120(12): 122503, 2018 Mar 23.
Artículo en Inglés | MEDLINE | ID: mdl-29694087

RESUMEN

A beam containing a substantial component of both the J^{π}=5^{+}, T_{1/2}=162 ns isomeric state of ^{18}F and its 1^{+}, 109.77-min ground state is utilized to study members of the ground-state rotational band in ^{19}F through the neutron transfer reaction (d,p) in inverse kinematics. The resulting spectroscopic strengths confirm the single-particle nature of the 13/2^{+} band-terminating state. The agreement between shell-model calculations using an interaction constructed within the sd shell, and our experimental results reinforces the idea of a single-particle-collective duality in the descriptions of the structure of atomic nuclei.

11.
Phys Rev Lett ; 119(7): 072701, 2017 Aug 18.
Artículo en Inglés | MEDLINE | ID: mdl-28949677

RESUMEN

The existence of ^{26}Al (t_{1/2}=7.17×10^{5} yr) in the interstellar medium provides a direct confirmation of ongoing nucleosynthesis in the Galaxy. The presence of a low-lying 0^{+} isomer (^{26}Al^{m}), however, severely complicates the astrophysical calculations. We present for the first time a study of the ^{26}Al^{m}(d,p)^{27}Al reaction using an isomeric ^{26}Al beam. The selectivity of this reaction allowed the study of ℓ=0 transfers to T=1/2, and T=3/2 states in ^{27}Al. Mirror symmetry arguments were then used to constrain the ^{26}Al^{m}(p,γ)^{27}Si reaction rate and provide an experimentally determined upper limit of the rate for the destruction of isomeric ^{26}Al via radiative proton capture reactions, which is expected to dominate the destruction path of ^{26}Al^{m} in asymptotic giant branch stars, classical novae, and core collapse supernovae.

12.
Phys Rev Lett ; 114(8): 082501, 2015 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-25768759

RESUMEN

A pair of transverse wobbling bands is observed in the nucleus ^{135}Pr. The wobbling is characterized by ΔI=1, E2 transitions between the bands, and a decrease in the wobbling energy confirms its transverse nature. Additionally, a transition from transverse wobbling to a three-quasiparticle band comprised of strong magnetic dipole transitions is observed. These observations conform well to results from calculations with the tilted axis cranking model and the quasiparticle rotor model.

13.
BMJ Open ; 4(12): e005346, 2014 Dec 08.
Artículo en Inglés | MEDLINE | ID: mdl-25488095

RESUMEN

OBJECTIVE: The objective of this study was to assess the prevalence of risk factors for coronary artery disease (CAD) in government employees across India. METHODS: The study population consisted of government employees in different parts of India ({n=10,642 men and n=1966 women; age 20-60 years}) and comprised various ethnic groups living in different environmental conditions. Recruitment was carried out in 20 cities across 14 states, and in one union territory. All selected individuals were subjected to a detailed questionnaire, medical examinations and anthropometric measurements. Blood samples were collected for blood glucose and serum lipid profile estimation, and resting ECG was recorded. Results were analysed using appropriate statistical tools. RESULTS: The study revealed that 4.6% of the study population had a family history of premature CAD. The overall prevalence of diabetes was 16% (5.6% diagnosed during the study and the remaining 10.4% already on medication). Hypertension was present in 21% of subjects. The prevalence of dyslipidemia was significantly high, with 45.6% of study subjects having a high total cholesterol/high density lipoprotein ratio. Overall, 78.6% subjects had two or more risk factors for CAD. CONCLUSIONS: The present study demonstrates a high prevalence of CAD risk factors in the Indian urban population. Therefore, there is an immediate need to initiate measures to raise awareness of these risk factors so that individuals at high risk for future CAD can be managed.


Asunto(s)
Enfermedad de la Arteria Coronaria/epidemiología , Medición de Riesgo/métodos , Población Urbana , Adulto , Femenino , Humanos , India/epidemiología , Masculino , Persona de Mediana Edad , Prevalencia , Factores de Riesgo , Adulto Joven
14.
Neuroscience ; 217: 84-95, 2012 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-22579982

RESUMEN

Histamine acts centrally to increase energy expenditure and reduce body weight by mechanisms not fully understood. It has been suggested that in the obese state hypothalamic histamine signaling is altered. Previous studies have also shown that histamine acting in the preoptic area controls thermoregulation. We aimed to study the influence of preoptic histamine on body temperature and energy homeostasis in control and obese mice. Activating histamine receptors in the preoptic area by increasing the concentration of endogenous histamine or by local injection of specific agonists induced an elevation of core body temperature and decreased respiratory exchange ratio (RER). In addition, the food intake was significantly decreased. The hyperthermic effect was associated with a rapid increase in mRNA expression of uncoupling proteins in thermogenic tissues, the most pronounced being that of uncoupling protein (UCP) 1 in brown adipose tissue and of UCP2 in white adipose tissue. In diet-induced obese mice histamine had much diminished hyperthermic effects as well as reduced effect on RER. Similarly, the ability of preoptic histamine signaling to increase the expression of uncoupling proteins was abolished. We also found that the expression of mRNA encoding the H1 receptor subtype in the preoptic area was significantly lower in obese animals. These results indicate that histamine signaling in the preoptic area modulates energy homeostasis by regulating body temperature, metabolic parameters and food intake and that the obese state is associated with a decrease in neurotransmitter's influence.


Asunto(s)
Regulación de la Temperatura Corporal/fisiología , Histamina/metabolismo , Homeostasis/fisiología , Obesidad/metabolismo , Receptores Histamínicos/metabolismo , Tejido Adiposo Pardo/efectos de los fármacos , Tejido Adiposo Pardo/metabolismo , Animales , Regulación de la Temperatura Corporal/efectos de los fármacos , Dimaprit/análogos & derivados , Dimaprit/farmacología , Ingestión de Alimentos/efectos de los fármacos , Ingestión de Alimentos/fisiología , Metabolismo Energético/efectos de los fármacos , Metabolismo Energético/fisiología , Agonistas de los Receptores Histamínicos/farmacología , Homeostasis/efectos de los fármacos , Ratones , Ratones Obesos , Área Preóptica/efectos de los fármacos , Área Preóptica/metabolismo
15.
Genome ; 53(8): 637-42, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20725151

RESUMEN

Many genes express multiple transcript isoforms generated by alternative splicing of mRNA. Using real-time PCR, it is straightforward to determine the relative expression level of each isoform independently. However, it is less trivial to determine the relative proportions of different isoforms in a cDNA sample. The relative proportions of different isoforms can be important, as a small change in a highly abundant transcript may be more relevant than a large change in a minimally expressed transcript. Currently, determining the relative proportions of isoforms requires the construction of a standard curve using recombinant plasmid DNA or genomic DNA. As recombinant or genomic DNA standards often amplify with different efficiencies to cDNA samples, they may give under- or overestimations of isoform abundances. The method described in this article uses a titration curve generated from the same cDNA samples measured in the experiment. By using samples with different levels of separate isoforms, it is possible to derive linear equations which, when solved, allow the determination of the proportion of each isoform within the samples under study.


Asunto(s)
Reacción en Cadena de la Polimerasa/métodos , Isoformas de Proteínas/análisis , Isoformas de Proteínas/genética , ARN Mensajero/análisis , Células 3T3-L1 , Adipocitos/metabolismo , Adipocitos/fisiología , Animales , Diferenciación Celular/genética , Ratones , Modelos Biológicos , PPAR gamma/genética , PPAR gamma/metabolismo , Reacción en Cadena de la Polimerasa/normas , ARN Mensajero/genética , ARN Ribosómico 18S/genética , ARN Ribosómico 18S/metabolismo , Estándares de Referencia
16.
Int J Obes (Lond) ; 34(12): 1695-705, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-20514047

RESUMEN

AIM: The Wnt/ß-catenin signaling network offers potential targets to diagnose and uncouple obesity from its metabolic complications. In this study, we investigate the role of the Wnt antagonist, secreted frizzled-related protein 1 (SFRP1), in promoting adipogenesis in vitro and adipose tissue expansion in vivo. METHODS: We use a combination of human and murine, in vivo and in vitro models of adipogenesis, adipose tissue expansion and obesity-related metabolic syndrome to profile the involvement of SFRP1. RESULTS: SFRP1 is expressed in both murine and human mature adipocytes. The expression of SFRP1 is induced during in vitro adipogenesis, and SFRP1 is preferentially expressed in mature adipocytes in human adipose tissue. Constitutive ectopic expression of SFRP1 is proadipogenic and inhibits the Wnt/ß-catenin signaling pathway. In vivo endogenous levels of adipose SFRP1 are regulated in line with proadipogenic states. However, in longitudinal studies of high-fat-diet-fed mice, we observed a dynamic temporal but biphasic regulation of endogenous SFRP1. In agreement with this profile, we observed that SFRP1 expression in human tissues peaks in patients with mild obesity and gradually falls in morbidly obese subjects. CONCLUSIONS: Our results suggest that SFRP1 is an endogenous modulator of Wnt/ß-catenin signaling and participates in the paracrine regulation of human adipogenesis. The reduced adipose expression of SFRP1 in morbid obesity and its knock-on effect to prevent further adipose tissue expansion may contribute to the development of metabolic complications in these individuals.


Asunto(s)
Adipogénesis , Tejido Adiposo Blanco/fisiología , Obesidad Mórbida/metabolismo , Proteínas/fisiología , Proteínas Wnt/metabolismo , beta Catenina/fisiología , Adipocitos Blancos/metabolismo , Anciano , Animales , Diferenciación Celular , Femenino , Expresión Génica , Humanos , Péptidos y Proteínas de Señalización Intracelular , Masculino , Ratones , Obesidad , Obesidad Mórbida/fisiopatología , Proteínas/genética , Proteínas/metabolismo , Transducción de Señal
17.
Methods Find Exp Clin Pharmacol ; 32(4): 233-5, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-20508870

RESUMEN

Wheat grass is used as a general health tonic and is reported to be effective against several medical disorders, although detailed literature is not available. Besides drug therapy, a number of medicinal plants are effective in treating hyperlipidemia. This study examined the effects of wheat grass on high-fat diet-induced hyperlipidemia in rabbits. Thirty rabbits were divided into 3 groups of 10 rabbits each, group I receiving a control diet, group II a high-fat diet and group III a high-fat diet together with wheat grass over a period of 10 weeks. Fasting serum samples from the animals were analyzed for total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), malondialdehyde (MDA), reduced glutathione (GSH) and vitamin C, and the results were compared. The high-fat diet resulted in hyperlipidemia and an increase in oxidative stress, indicated by a significant rise in MDA levels, whereas antioxidant levels of GSH and vitamin C were significantly reduced. Wheat grass supplementation with a high-fat diet resulted in improved lipid levels (decreased total cholesterol and increased HDL-C) together with significantly reduced MDA levels and increased GSH and vitamin C levels. These results indicate the beneficial role of wheat grass in ameliorating hyperlipidemia and the associated oxidative stress.


Asunto(s)
Antioxidantes/farmacología , Hiperlipidemias/tratamiento farmacológico , Estrés Oxidativo/efectos de los fármacos , Triticum/química , Animales , Ácido Ascórbico/metabolismo , Grasas de la Dieta/toxicidad , Femenino , Glutatión/efectos de los fármacos , Glutatión/metabolismo , Hiperlipidemias/fisiopatología , Masculino , Malondialdehído/metabolismo , Fitoterapia/métodos , Preparaciones de Plantas/farmacología , Conejos
18.
Chron Respir Dis ; 6(1): 19-29, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19176709

RESUMEN

Exhaled nitric oxide (eNO) used as an aid to the diagnosis and management of lung disease is receiving attention from pulmonary researchers and clinicians alike because it offers a noninvasive means to directly monitor airway inflammation. Research evidence suggests that eNO levels significantly increase in individuals with asthma before diagnosis, decrease with inhaled corticosteroid administration, and correlate with the number of eosinophils in induced sputum. These observations have been used to support an association between eNO levels and airway inflammation. This review presents an update on current opportunities regarding use of eNO in patient care, and more specifically on its potential usage for asthma diagnosis and monitoring. The review will also discuss factors that may complicate use of eNO as a diagnostic tool, including changes in disease severity, symptom response, and technical measurement issues. Regardless of the rapid, convenient, and noninvasive nature of this test, additional well-designed, long-term longitudinal studies are necessary to fully evaluate the clinical utility of eNO in asthma management.


Asunto(s)
Asma/diagnóstico , Biomarcadores/análisis , Pruebas Respiratorias , Óxido Nítrico/análisis , Asma/terapia , Humanos , Monitoreo Fisiológico
19.
Sarcoidosis Vasc Diffuse Lung Dis ; 26(2): 98-109, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-20560290

RESUMEN

Fraction of end tidal exhaled nitric oxide (FeNO) has been introduced as a non-invasive marker of airway inflammation in patients with asthma and may have value in monitoring disease activity in patients with sarcoidosis. This pilot study explored: 1) feasibility of the multiple flow rates maneuver to estimate alveolar (C(AlV)NO) and airway wall (J(AW)NO) NO in patients with sarcoidosis; and 2) utility of exhaled NO (FeNO, C(Alv)NO and J(AW)NO) measurements to detect and monitor treatment response in patients with active pulmonary sarcoidosis. Patients with sarcoidosis (n = 42) and healthy non-smokers (n = 20) underwent FeNO measurement at 7 flow-rates (50 to 400 ml/s). Using the Tsoukias and George (1998) model, C(Alv)NO and J(AW)NO were estimated. Both patients and healthy non-smokers were able to perform the multiple flow rates maneuver without discomfort, with first measurement success rate of 57% and 65%, respectively. No significant difference was found between patients with sarcoidosis and healthy non-smokers in exhaled NO. None were correlated with pulmonary function tests, except a significant negative correlation between C(Alv)NO and FVC% (p = 0.001) and DLCO% (p = 0.012). In 8 patients with active sarcoidosis, FeNO, C(Alv)NO or J(AW)NO were not different from those of patients with inactive sarcoidosis. Treatment of active sarcoidosis using oral prednisone and methotrexate did not show any consistent pattern of changes in C(Alv)NO or J(AW)NO. Due to a large inter-subject variability and difficulty controlling use of the inhaled corticosteroids, exhaled NO measurement did not appear to be a clinically useful method of monitoring disease progression in sarcoidosis.


Asunto(s)
Pruebas Respiratorias/métodos , Espiración , Óxido Nítrico/análisis , Alveolos Pulmonares/metabolismo , Sarcoidosis Pulmonar/metabolismo , Fibrosis Quística/metabolismo , Estudios de Factibilidad , Femenino , Volumen Espiratorio Forzado , Humanos , Masculino , Persona de Mediana Edad , Proyectos Piloto , Pruebas de Función Respiratoria , Sarcoidosis Pulmonar/diagnóstico , Sarcoidosis Pulmonar/fisiopatología , Índice de Severidad de la Enfermedad
20.
Cell Death Differ ; 14(7): 1361-73, 2007 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-17464333

RESUMEN

Tumour necrosis factor-alpha (TNF-alpha), a proinflammatory cytokine, is a potent negative regulator of adipocyte differentiation. However, the mechanism of TNF-alpha-mediated antiadipogenesis remains incompletely understood. In this study, we first confirm that TNF-alpha inhibits adipogenesis of 3T3-L1 preadipocytes by preventing the early induction of the adipogenic transcription factors peroxisome proliferator-activated receptor-gamma (PPARgamma) and CCAAT/enhancer binding protein-alpha (C/EBPalpha). This suppression coincides with enhanced expression of several reported mediators of antiadipogenesis that are also targets of the Wnt/beta-catenin/T-cell factor 4 (TCF4) pathway. Indeed, we found that TNF-alpha enhanced TCF4-dependent transcriptional activity during early antiadipogenesis, and promoted the stabilisation of beta-catenin throughout antiadipogenesis. We analysed the effect of TNF-alpha on adipogenesis in 3T3-L1 cells in which beta-catenin/TCF signalling was impaired, either via stable knockdown of beta-catenin, or by overexpression of dominant-negative TCF4 (dnTCF4). The knockdown of beta-catenin enhanced the adipogenic potential of 3T3-L1 preadipocytes and attenuated TNF-alpha-induced antiadipogenesis. However, beta-catenin knockdown also promoted TNF-alpha-induced apoptosis in these cells. In contrast, overexpression of dnTCF4 prevented TNF-alpha-induced antiadipogenesis but showed no apparent effect on cell survival. Finally, we show that TNF-alpha-induced antiadipogenesis and stabilisation of beta-catenin requires a functional death domain of TNF-alpha receptor 1 (TNFR1). Taken together these data suggest that TNFR1-mediated death domain signals can inhibit adipogenesis via a beta-catenin/TCF4-dependent pathway.


Asunto(s)
Adipocitos/metabolismo , Adipogénesis/fisiología , Tejido Adiposo/metabolismo , Factores de Transcripción TCF/metabolismo , Factor de Necrosis Tumoral alfa/fisiología , beta Catenina/metabolismo , Adipocitos/efectos de los fármacos , Adipogénesis/efectos de los fármacos , Animales , Apoptosis/efectos de los fármacos , Apoptosis/fisiología , Proteínas Potenciadoras de Unión a CCAAT/metabolismo , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/fisiología , Regulación hacia Abajo/fisiología , Ratones , Células 3T3 NIH , PPAR gamma/metabolismo , Receptores Tipo I de Factores de Necrosis Tumoral/efectos de los fármacos , Receptores Tipo I de Factores de Necrosis Tumoral/metabolismo , Transducción de Señal/efectos de los fármacos , Transducción de Señal/fisiología , Proteína 2 Similar al Factor de Transcripción 7 , Activación Transcripcional/efectos de los fármacos , Activación Transcripcional/fisiología , Factor de Necrosis Tumoral alfa/farmacología , beta Catenina/genética
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