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1.
Phys Rev Lett ; 124(4): 041601, 2020 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-32058745

RESUMEN

We explore the spacetime structure near nonextremal horizons in any spacetime dimension greater than two and discover a wealth of novel results: (i) Different boundary conditions are specified by a functional of the dynamical variables, describing inequivalent interactions at the horizon with a thermal bath. (ii) The near horizon algebra of a set of boundary conditions, labeled by a parameter s, is given by the semidirect sum of diffeomorphisms at the horizon with "spin-s supertranslations." For s=1 we obtain the first explicit near horizon realization of the Bondi-Metzner-Sachs algebra. (iii) For another choice, we find a nonlinear extension of the Heisenberg algebra, generalizing recent results in three spacetime dimensions. This algebra allows us to recover the aforementioned (linear) ones as composites. (iv) These examples allow us to equip not only black holes, but also cosmological horizons with soft hair. We also discuss implications of soft hair for black hole thermodynamics and entropy.

2.
Eur J Clin Pharmacol ; 75(8): 1037-1046, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-30915521

RESUMEN

AIM AND BACKGROUND: Reducing inflammation by nutritional supplements may help to reduce the risk of many chronic diseases. Our aim in this meta-analysis was to determine the effect of L-carnitine on inflammatory mediators including C-reactive protein (CRP), tumor necrosis factor-α (TNF-α), and interleukin-6 (IL-6). METHODS: Our systematic search to find relevant randomized clinical trials (RCTs) was performed up to October 2018 using ISI Web of Science, Google Scholar, PubMed/Medline, and SCOPUS. In this meta-analysis, the weighted mean differences (WMD) with standard errors (SE) were used to pool the data. WMD was calculated by subtracting change-from-baseline mean values in the control group from change-from-baseline mean values in the intervention group in each study. To identify heterogeneity among studies, the I2 statistic was employed. The protocol was registered with PROSPERO (No. CRD42019116695). RESULTS: Thirteen articles were included in our systematic review and meta-analysis. The results of the meta-analysis indicated that L-carnitine supplementation was significantly associated with lower levels of CRP in comparison to controls (WMD = -1.23 mg/L; 95% CI: -1.73, -0.72 mg/dL; P < 0.0001). Also, a slight but statistically significant decrease was observed in IL-6 and TNF-α levels (WMD = -0.85 pg/dL; 95% CI: -1.38, -0.32 pg/dL; P = 0.002 and WMD = -0.37 pg/dL; 95% CI: -0.68, -0.06 pg/dL; P = 0.018, respectively). CONCLUSION: Our results indicate that L-carnitine reduced inflammatory mediators, especially in studies with a duration of more than 12 weeks. Further studies with different doses and intervention durations and separately in men and women are necessary.


Asunto(s)
Carnitina/administración & dosificación , Suplementos Dietéticos , Mediadores de Inflamación/sangre , Inflamación/dietoterapia , Proteína C-Reactiva/análisis , Humanos , Inflamación/sangre , Interleucina-6/sangre , Ensayos Clínicos Controlados Aleatorios como Asunto , Factores Sexuales , Factores de Tiempo , Resultado del Tratamiento , Factor de Necrosis Tumoral alfa/sangre
3.
Appl Opt ; 57(28): 8193-8198, 2018 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-30461769

RESUMEN

We have theoretically studied the Goos-Hänchen (GH) shifts of both the reflected and transmitted probe beams emerging from a cavity consisting of a hybrid system of a coupled quantum dot (QD) nanostructure and a metallic nanoparticle (MNP). It is realized that the GH shifts in the transmitted and reflected light beams can be enhanced due to the surface plasmon effect in the MNP. Also, it is shown that by adjusting the distance between QD and MNP and polarization control between probe field and major axis of the hybrid system, the simultaneous negative and positive GH shifts in reflected and transmitted light beams can occur. Moreover, the effects of the intensity and detuning of the coupling light on the GH shift properties of the reflected and transmitted lights have been discussed. We have found that under different parametric conditions of the hybrid system, the GH shifts of the reflected and transmitted light beams can be adjusted by tuning the intensity and controlling the detuning of the coupling field. The results show that our proposed model may be used for future optical sensor devices based on MNP hybrid systems.

4.
Med Sci Law ; 53(2): 85-9, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23160604

RESUMEN

The distinctive morphology of the human innominate bone (os coxae) and its clear sexual dimorphism make it of interest from anatomical, anthropological and forensic points of view. The features of the greater sciatic notch of the coxae are characteristic and are commonly used to determine sex in unknown individuals. In this study, several measurements of the greater sciatic notch, e.g. width (AB), depth (OC) and width of the posterior segment (OB) were taken and indices I and II were calculated in 64 adult (32 men and 32 women) and side (right: left) coxae radiography (A-P view). Results indicated that out of all the parameters studied, width of the notch (right and left) (P < 0.001), posterior segment width (right and left) (P < 0.001), right (P = 0.036) and left (P = 0.008) index II of notch were found to be significantly greater in women as compared with men. Discriminant function analysis showed that the accuracy of sex determination varied from 100% in the men and 40% in the women groups to 70% for the total group. These results can be used as an aid to the identification of human skeletal remains in Iranian people.


Asunto(s)
Huesos Pélvicos/diagnóstico por imagen , Determinación del Sexo por el Esqueleto/métodos , Adulto , Anciano , Análisis Discriminante , Femenino , Antropología Forense , Humanos , Irán , Masculino , Persona de Mediana Edad , Huesos Pélvicos/anatomía & histología , Adulto Joven
5.
Matern Child Health J ; 14(1): 141-5, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19093194

RESUMEN

The aim of this study was to examine the exposure of lactating mothers to aflatoxins using aflatoxin M(1) in breast milk as a biomarker for exposure and to detect its determining factors and possible effects on child growth. A 9% sample of 2022 lactating women who exclusively breastfed their infants, including 91 lactating women of urban areas of Tabriz city and 91 lactating women of its rural areas were recruited by a geographical clustered sampling method. Breast milk samples and information on food intake were collected from subjects using structured food-frequency questionnaire. Extraction of AFM(1) was performed with the ELISA test procedure. Aflatoxin M(1) was detected in breast milk of 20 out of 91 mothers (22%) in concentrations of 6.96 +/- 0.94 (pg/ml) in rural areas. Aflatoxin M(1) contamination was not present in samples of urban areas. The presence of aflatoxin M(1) was significantly associated with consumption of local milk (beta = 0.71, P < 0.001) and stunted growth in children (beta = -0.31, P < 0.015). These findings emphasize the need for developing strategies to reduce exposure to aflatoxin, possibly involving interventions targeted at reducing contamination of foods.


Asunto(s)
Aflatoxina M1/análisis , Leche Humana/química , Venenos/análisis , Adulto , Encuestas sobre Dietas , Exposición a Riesgos Ambientales , Femenino , Contaminación de Alimentos , Humanos , Irán , Adulto Joven
6.
Eur J Clin Nutr ; 61(7): 892-5, 2007 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-17311064

RESUMEN

BACKGROUND: Studies on the determination of carnitine levels and nutritional status in patients of type II diabetes. OBJECTIVE: We designed this study to determine changes of serum-free L-carnitine in type II diabetic women. DESIGN: A cross-sectional study (case-control study). SETTING: Clinical of Endocrinology and Metabolism, Sina Hospital, Pharmacological Research Center, Tabriz Medical university, Iran. PATIENTS AND METHODS: Taking into account the importance of the control of diabetes, in the present case-control study, the levels of serum-free L-carnitine, blood glucose and lipids, systolic and diastolic blood pressure, body mass index (BMI) and nutritional status assessed in the case and control groups which were selected by the simple sampling method. The control group (n=18) included patients with no complications and the case group (n=33) was grouped into three subgroups including patients with retinopathy, hyperlipidemia and neuropathy. RESULTS: Study results indicated that the mean serum-free L-carnitine concentration in the case group was significantly lower than its mean concentration level in the control group, 39.63+/-8.99 vs 53.42+/-0.93 micromol/l, respectively (P<0.001). Serum-free L-carnitine in retinopathy, hyperlipidemia and neuropathy case subgroups were 39.03+/-9.89, 39.63+/-8.99 and 40.44+/-12.50 micromol/l, respectively (P>0.05). No significant difference was found between the serum-free carnitine levels of the case subgroups. The mean blood glucose, triglycerides, total cholesterol, low-density lipoprotein cholesterol, very low-density lipoprotein cholesterol levels and systolic and diastolic blood pressure were significantly higher in the case group than in the control group. CONCLUSION: In this study, the mean serum-free L-carnitine levels in diabetic patients with complications was almost 25% lower than in diabetic patients with no complications. On the basis of the study results, carnitine supplementation in diabetic patients, especially in patients with diabetes complications, might be useful.


Asunto(s)
Presión Sanguínea/fisiología , Carnitina/sangre , Carnitina/deficiencia , Complicaciones de la Diabetes/sangre , Diabetes Mellitus Tipo 2/sangre , Lípidos/sangre , Glucemia/metabolismo , Índice de Masa Corporal , Estudios de Casos y Controles , Estudios Transversales , Neuropatías Diabéticas/sangre , Retinopatía Diabética/sangre , Femenino , Humanos , Microcirculación , Persona de Mediana Edad , Estado Nutricional
7.
J Phys Chem B ; 121(32): 7633-7645, 2017 08 17.
Artículo en Inglés | MEDLINE | ID: mdl-28771005

RESUMEN

Conformational diseases have been investigated extensively in recent years; as a result, a number of drug candidates have been introduced as amyloid inhibitors; however, no effective therapies have been put forward. RS-0406 with pyridazine as its core chemical structure has so far shown promising results in inhibiting amyloid formation. In the present work, using molecular dynamics, we undertook the investigation of RS-0406 interactions with U-shaped Aß1-42 and Aß1-40 pentamers, Aß1-42 monomers, and double-horseshoe-like Aß1-42. To set better parameters for the small molecule, experimental and computational log P values were obtained. In addition, an analogue of RS-0406 was also simulated for comparison. The results indicate that RS-0406 may inhibit amyloid formation exploiting two different mechanisms. One mechanism includes stabilizing the α helix, in the monomer peptide, by binding to the flanking sites of the amyloidogenic region. The second mechanism mediates through interaction of the small molecules near the amyloidogenic regions, leading to destabilization of the ß-sheets in both the U-shaped and the S-shaped fibril. Notably, a persistent interaction between the imidazole ring of His14 from an S-shaped structure and the pyridazine ring of RS-0406 was observed. The unique structural properties of RS-0406, including aromaticity, H-bonding capability, flexibility, and symmetry, allow the small molecule to noticeably affect amyloid formation.


Asunto(s)
Amiloide/antagonistas & inhibidores , Piridazinas/metabolismo , Amiloide/metabolismo , Péptidos beta-Amiloides/antagonistas & inhibidores , Péptidos beta-Amiloides/metabolismo , Diaminas/química , Diaminas/metabolismo , Humanos , Simulación de Dinámica Molecular , Fragmentos de Péptidos/antagonistas & inhibidores , Fragmentos de Péptidos/metabolismo , Unión Proteica , Estructura Secundaria de Proteína , Piridazinas/química
8.
Can J Gastroenterol ; 14(4): 333-6, 2000 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10799087

RESUMEN

Local immunotherapy with an attenuated live strain of Mycobacterium bovis, bacillus Calmette-Guérin (BCG), is an effective and frequently used treatment for in situ transitional cell carcinoma (TCC) of the bladder. Success rates are high, and serious side effects are infrequent but can affect every organ system. A 79-year-old patient with recently diagnosed TCC who was treated with intravesical BCG for a recurrence after initial surgical treatment is reported. After unsuccessful attempts at bladder catheterization with the creation of a false passage for his third treatment, BCG was instilled via a suprapubic catheter the same day and again a week later. Two weeks after the third BCG instillation, the patient presented with profound lethargy and weakness to the point of not being able to get up out of a chair. He was febrile, anorexic, icteric and had hepatosplenomegaly. Disseminated BCG infection was suspected on the basis of history, clinical examination and a liver biopsy that showed noncaseating granulomatous hepatitis. Empirical treatment was started with antituberculous combination therapy. A short course of an oral corticosteroid was given. Clinical improvement was marked and sustained so that the patient could be discharged home for the full six-month course of his treatment. Disseminated BCG infection with granulomatous hepatitis can be severe and life-threatening in cases where a large intravascular inoculum of BCG may have been given inadvertently.


Asunto(s)
Vacuna BCG/efectos adversos , Granuloma/microbiología , Hepatitis/microbiología , Administración Intravesical , Anciano , Vacuna BCG/administración & dosificación , Vacuna BCG/uso terapéutico , Carcinoma de Células Transicionales/terapia , Granuloma/patología , Hepatitis/patología , Humanos , Hígado/patología , Masculino , Neoplasias de la Vejiga Urinaria/terapia
9.
J Sch Health ; 63(7): 302-6, 1993 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-8246462

RESUMEN

Data from a statewide survey, conducted by the Indiana Prevention Resource Center, of 20,629 Indiana students in grades 5-12 were analyzed to determine the extent to which cigarette smoking predicted use of alcohol and other drugs and acted as a so-called "gateway drug." A three-stage purposive/quota cluster sampling strategy yielded a representative sample of Indiana students, stratified by grade. Cross-tabulated data revealed a strong, dose-dependent relationship between smoking behavior and binge drinking, as well as use of alcohol and illicit drugs. Daily pack-a-day smokers were three times more likely to drink alcohol, seven times more likely to use smokeless tobacco, and 10-30 times more likely to use illicit drugs than nonsmokers. A stepwise multiple regression analyzed the role that the student's perceptions of the risk of using drugs and of peer approval/disapproval of the student's drug use, gender, grade in school, and ethnic background played in predicting alcohol and other drug use.


Asunto(s)
Consumo de Bebidas Alcohólicas/epidemiología , Fumar/epidemiología , Trastornos Relacionados con Sustancias/epidemiología , Adolescente , Actitud Frente a la Salud , Niño , Femenino , Encuestas Epidemiológicas , Humanos , Indiana/epidemiología , Masculino , Grupo Paritario , Valor Predictivo de las Pruebas , Prevalencia , Análisis de Regresión , Asunción de Riesgos , Encuestas y Cuestionarios
12.
Phys Rev Lett ; 101(26): 261601, 2008 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-19113767

RESUMEN

We show that the Cohen-Glashow very special relativity (VSR) theory [A. G. Cohen and S. L. Glashow, Phys. Rev. Lett. 97, 021601 (2006)] can be realized as the part of the Poincaré symmetry preserved on a noncommutative Moyal plane with lightlike noncommutativity. Moreover, we show that the three subgroups relevant to VSR can also be realized in the noncommutative space-time setting. For all of these three cases, the noncommutativity parameter theta(mu upsilon) should be lightlike (theta(mu upsilon) theta mu upsilon = 0). We discuss some physical implications of this realization of the Cohen-Glashow VSR.

13.
Talanta ; 72(2): 620-5, 2007 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-19071664

RESUMEN

A simple and environment friendly method was developed for determination of Malathion content of analytical and commercial insecticide samples with no special preparation. Attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectra were characterized and 1000-2000cm(-1) region was selected for quantitative analysis utilizing partial least square (PLS) and two wavelength selection methods: (a) principal component regression (PCR) and (b) genetic algorithm (GA). Relative error of prediction (REP) was calculated in PLS, PCR-PLS and GA-PLS methods and was 3.536, 1.656 and 0.188, respectively. Proposed method is successfully applicable for quantification of Malathion in commercial grade samples and reliable results in comparison with known methods, confirms this idea.

14.
Phys Rev Lett ; 96(8): 081301, 2006 Mar 03.
Artículo en Inglés | MEDLINE | ID: mdl-16606163

RESUMEN

We present a new mechanism for creating the observed cosmic matter-antimatter asymmetry which satisfies all three Sakharov conditions from one common thread, gravitational waves. We generate lepton number through the gravitational anomaly in the lepton number current. The source term comes from elliptically polarized gravity waves that are produced during inflation if the inflaton field contains a CP-odd component. The amount of matter asymmetry generated in our model can be of realistic size for the parameters within the range of some inflationary scenarios and grand unified theories.

15.
Am J Dig Dis ; 23(12): 1144-7, 1978 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-736021

RESUMEN

A 67-year-old white man presented with bloody diarrhea and passed a 22-cm long segment of full-thickness sigmoid colon following a barium enema. He had advanced peripheral and cerebral vascular disease and had undergone pelvic irradiation for a bladder cancer five years previously. He recovered uneventfully from the bowel sloughage. This was apparently due to an intussusception of the sigmoid colon followed by the formation of adhesions between the edges of the adjacent viable bowel.


Asunto(s)
Colon Sigmoide , Intususcepción , Anciano , Colon Sigmoide/diagnóstico por imagen , Colon Sigmoide/patología , Enfermedades del Colon/diagnóstico por imagen , Enfermedades del Colon/patología , Humanos , Intususcepción/diagnóstico por imagen , Intususcepción/patología , Masculino , Radiografía
16.
Can Med Assoc J ; 119(7): 715-9, 1978 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-709471

RESUMEN

In three cases of pancreaticocolonic fistula presenting before the stage of exsanguinating hemorrhage of severe sepsis the problem was diagnosed on the basis of the clinical history, visualization of the terminal part of the fistula by roentgenography after a barium enema had been given and, in two cases, demonstration of the communication with the pancreatic ductal system by endoscopic retrograde pancreatography. The lesions were repaired surgically. Pancreaticocolonic fistula should be suspected in a patient with upper abdominal pain who has a history of abdominal pain and excessive alcohol consumption and in whom diarrhea and fever, hematochezia or a disappearing abdominal mass develops. Characteristically barium will collect in the terminal part of the fistula and thus permit a tentative diagnosis; the diagnosis can then be confirmed by endoscopic retrograde pancreatography. With this approach surgical treatment can be carried out earlier and the often fatal course of the disorder can be averted.


Asunto(s)
Enfermedades del Colon/etiología , Fístula Intestinal/etiología , Fístula Pancreática/etiología , Pancreatitis/complicaciones , Adulto , Anciano , Enfermedad Crónica , Enfermedades del Colon/diagnóstico por imagen , Enfermedades del Colon/cirugía , Endoscopía/métodos , Humanos , Fístula Intestinal/diagnóstico por imagen , Fístula Intestinal/cirugía , Masculino , Persona de Mediana Edad , Páncreas/diagnóstico por imagen , Fístula Pancreática/diagnóstico por imagen , Fístula Pancreática/cirugía , Pancreatitis/diagnóstico por imagen , Radiografía
17.
Phys Rev Lett ; 87(1): 011301, 2001 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-11461456

RESUMEN

In this paper we show that noncommutativity in spatial coordinates can generate magnetic field in the early Universe on a horizon scale. The strength of such a magnetic field depends on the number density of massive charged particles present at a given moment. This allows us to trace back the temperature dependence of the noncommutativity scale from the bounds on primordial magnetic field coming from nucleosynthesis.

18.
Can Med Assoc J ; 112(7): 857-64, 1975 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-1122459

RESUMEN

Achalasia of the esophagus occurred in association with gastric carcinoma involving the cardia. Except in a limited area subjacent to the squamocolumnar junction, the pathologic findings were unusual in that the myenteric plexus of the body of the esophagus was intact and apparently uninvolved. The hypothesis is advanced that, in this instance, the achalasia could be classified as a tumour-associated funnctional disorder due to distant neural involvement rather than to local invasion with plexus destruction.


Asunto(s)
Adenocarcinoma/complicaciones , Acalasia del Esófago/etiología , Plexo Mientérico , Neoplasias Gástricas/complicaciones , Adenocarcinoma/diagnóstico , Adenocarcinoma/fisiopatología , Acalasia del Esófago/diagnóstico , Unión Esofagogástrica/diagnóstico por imagen , Esófago/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , Radiografía , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/fisiopatología
19.
Gastroenterology ; 89(2): 352-6, 1985 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-4007426

RESUMEN

Careful endoscopic survey of the upper esophagus indicates that a visually recognizable patch of gastric mucosa is grossly visible much more commonly than is generally recognized. Sixteen instances were found in 420 sequential endoscopies, an incidence of 3.8%. The gastric mucosal rest presented as a velvety red patch with a distinct border, varying from a few millimeters in diameter to complete encirclement of the esophagus, was occasionally paired, and was found either at or just below the upper esophageal sphincter. In all instances except one the patch consisted of gastric-type mucosa containing both parietal and chief cells; in the single exception, it consisted of gastric-type mucous glands without parietal cells. Although larger patches can be shown to function under stimulation (they produce a local drop in pH with pentagastrin stimulation), there are usually no apparent associated clinical symptoms.


Asunto(s)
Coristoma/patología , Neoplasias Esofágicas/patología , Mucosa Gástrica , Adulto , Anciano , Epitelio/patología , Esofagoscopía , Femenino , Ácido Gástrico/metabolismo , Mucosa Gástrica/patología , Humanos , Concentración de Iones de Hidrógeno , Masculino , Persona de Mediana Edad , Membrana Mucosa/patología , Células Parietales Gástricas
20.
Phys Rev Lett ; 86(13): 2716-9, 2001 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-11290022

RESUMEN

We have calculated the energy levels of the hydrogen atom as well as the Lamb shift within the noncommutative quantum electrodynamics theory. The results show deviations from the usual QED both on the classical and the quantum levels. On both levels, the deviations depend on the parameter of space/space noncommutativity.

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