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1.
Sci Rep ; 12(1): 10734, 2022 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-35750758

RESUMO

Regarding the confinement of light at nanoscale dimensions in plasmonic structures, we try to show the impact of hot atomic vapor spectroscopy on a miniaturized scale. In such a combined structure, resonant coupling of the atom to plasmonic mode provides diverse ways to control the optical response of the system. We fabricate an atomic plasmonic cell based on Rubidium atomic vapor and gold plasmonic thin film onto the Kretschmann setup to introduce resonant coupling (EIT-like) of atom-plasmons as a tunable all-optical bandpass filter, switch, or logic gates. These all-optical devices such as NOR and XNOR logic gates are well done based on the filter by incidence angle of light, temperature as well as the external magnetic field. We believe the possibility of easy modulation of atomic susceptibility, not only through direct alteration on atoms but also through common methods available for modulation of plasmonic mode, has the potential to design and fabricate modern all-optical devices.

2.
Sci Rep ; 11(1): 21668, 2021 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-34737391

RESUMO

Various efforts have been made to determine the polarization state of evanescent waves in different structures. The present study shows the reliability of magneto-optical spectroscopy of D1 and D2 lines of rubidium metal and polarization-dependent transitions to investigate and trace the changes in the polarization state of evanescent fields during total internal reflection over different angles. For this purpose, we design and fabricate atomic- evanescent Rb vapor cells and examine the effect of polarization changes of evanescent waves, depending on the propagation direction of evanescent waves in anisotropic rubidium vapor media under 88 mT external magnetic field by different configurations theoretically and experimentally. The results confirm the dependency of allowed [Formula: see text] transitions on the magneto optical configuration as a tool to determine changes in the polarization of evanescent waves in more complicated wave states in anisotropic media.

3.
Sci Rep ; 10(1): 17080, 2020 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-33051555

RESUMO

Various efforts have been made to overcome Doppler broadening in hyperfine measurement limitations in the atomic vapors spectroscopy and associated applications. The present study measured and calculated hyperfine resolved ellipsometric parameters through the near-normal reflectance spectra of the rubidium vapor cell in two experimental setups based on continuous and modulated pathway. The results indicated that valuable information could be extracted from the ellipsometric parameters about the atomic medium. Change in the ellipsometric parameters in each transition line confirms the existence of the elliptical polarization of the reflected light when it is exposed to the alkali metal vapor. Our results show that the ellipticity at 5S1/2 (Fg = 1, 2) → 5P1/2 (Fe = 1, 2) hyperfine transitions of 87Rb (D1 line) is small, and accordingly hyperfine transitions between the ground 5S1/2 (Fg = 2, 3) and excited 5P1/2 (Fe = 2, 3) states of the 85Rb isotope are considerable. These ellipsometric parameters, as phase difference, can trace the behavior of the relative orientation of the electric field and atom velocity in the interface based on van der Waals dipole-dipole interaction and is directly proportional to the strength of the light-matter interaction which extremely useful instead complicated atomic spectroscopic methods.

4.
J Pediatr Urol ; 14(2): 108-115, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29456119

RESUMO

INTRODUCTION: An extremely variable and high prevalence of urinary tract infection (UTI) in infants with prolonged jaundice has been reported in Iran. However, there is no research from the area that has attempted to estimate pooled prevalence of UTI from considerably diverse evidence. Therefore, this systematic review and meta-analysis study aimed to estimate the prevalence of UTI in infants with prolonged jaundice who were admitted into clinics or hospitals in Iran. METHODS: A systematic review and meta-analysis was conducted of published articles on UTI prevalence in infants with prolonged jaundice in Iran. Electronic databases were searched, including Web of Sciences, PubMed/Medline, Scopus, Iranian Scientific Information Database (SID) and Iranmedex, for both English and Persian language articles published between January, 2000 and March, 2017. All possible combinations of the following keywords were used: jaundice, icterus, hyperbilirubinemia during infancy, infection and neonatal. Nine studies that reported prevalence of UTI in infants with prolonged jaundice were included. The overall prevalence of UTI was estimated using random-effects meta-analysis models. RESULTS: A total of 1750 infants were pooled to estimate the overall prevalence of UTI in infants with prolonged jaundice. The prevalence reported by the studies included in this literature review was extremely variable and ranged 0.6-53.9%. The overall prevalence was 11% (95% Confidence Interval (CI): 5.0-18.0), and Escherichia coli was found to be the main cause of UTI. CONCLUSION: The overall prevalence of UTI was 11%, and E. coli was the main cause of UTI in infants with prolonged jaundice. Screening of UTI should be considered for infants with prolonged jaundice.


Assuntos
Hospitalização/estatística & dados numéricos , Icterícia/epidemiologia , Infecções Urinárias/epidemiologia , Doença Crônica , Feminino , Humanos , Lactente , Irã (Geográfico)/epidemiologia , Icterícia/diagnóstico , Icterícia/terapia , Masculino , Prevalência , Índice de Gravidade de Doença , Infecções Urinárias/diagnóstico , Infecções Urinárias/terapia
5.
Injury ; 48(2): 262-269, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28087117

RESUMO

AIM: Erythropoietin (EPO) is shown to exert protective effects on different tissues in haemorrhagic shock (HS) states. Nitric oxide (NO), as a multifunctional signaling molecule, is implicated in diverse physiologic and pathologic processes. In order to understand the exact mechanism of EPO protection, in this study we evaluated the role of different NOS enzymes in the EPO signaling pathway in male rats. METHODS: Rats were randomized to five groups: 1) Sham, 2) HS 3) EPO 4) L-NAME, a non-specific NOS inhibitor 5) 1400W, a specific iNOS inhibitor. HS was induced by withdrawal of 50% of total blood volume. After 2h, resuscitation was performed with the shed blood and Ringer's lactate. In group 3, rats were treated with EPO (300IU/kg, i.v.) over 10min before HS induction. In the L-NAME and 1400W groups, L-NAME (10mg/kg, i.p.) and 1400W (2mg/kg, i.p.) were administered 30min before EPO injection. Blood and kidney tissue samples were obtained 3h after resuscitation. RESULTS: EPO increased the survival rate and significantly improved kidney function and histology compared to the HS group. There were less renal oxidative stress, apoptosis and systemic inflammatory responses in the EPO group. EPO increased eNOS and more abundantly iNOS mRNA expressions. L-NAME and 1400W significantly abolished all beneficial effects of EPO. CONCLUSION: In this in vivo animal model, we showed that EPO administration prior to HS attenuates renal injury and dysfunction in rats. The protective effects of EPO may be mediated by nitric oxide and the expression of different NOS enzymes, especially iNOS isoform.


Assuntos
Injúria Renal Aguda/patologia , Eritropoetina/farmacologia , Rim/patologia , Óxido Nítrico Sintase Tipo II/metabolismo , Óxido Nítrico/metabolismo , Choque Hemorrágico/patologia , Animais , Modelos Animais de Doenças , Rim/efeitos dos fármacos , Masculino , Estresse Oxidativo , Ratos , Ratos Wistar
6.
Pak J Biol Sci ; 16(7): 309-16, 2013 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-24498797

RESUMO

The anti-inflammatory and anti-nociceptive properties of Rosmarinus officinalis L. (ROL) extract and its major constituent, carnosol in male NMRI mice (W:25-30 g) have been evaluated in the present study. Formalin (2%, 20 microL) was injected into the plantar portion of the hind paw and resulting pain and inflammation was studied for 60 min. The plant extract, carnosol and other drugs were administered intraperitoneally or subcutaneously 30 min before formalin injection. In a separate experiment, the effects of the extract and carnosol on plasma corticosterone levels and activity of the enzymes cyclooxygenase type 1 and 2 (COX1 and COX2) were investigated. Injection of different doses of ROL and carnosol reduced pain in the phase 2 of the formalin test, which was not inhibited by naloxone and/or memantine. In addition, pretreatment of the animals with ROL and/or carnosol reduces the formalin-induced inflammation. Furthermore, the extract and carnosol did not affect plasma corticosterone levels compared with the control group. Interestingly, both the extract and carnosol inhibited COX1 and COX2 activity. It could be concluded that ROL extract and carnosol suppressed pain and inflammation induced by formalin injection, which may be due to inhibition of COX1 and COX2 enzymes activity.


Assuntos
Abietanos/farmacologia , Álcoois/química , Analgésicos/farmacologia , Anti-Inflamatórios/farmacologia , Inflamação/prevenção & controle , Dor/prevenção & controle , Extratos Vegetais/farmacologia , Rosmarinus , Solventes/química , Abietanos/administração & dosagem , Analgésicos/administração & dosagem , Animais , Anti-Inflamatórios/administração & dosagem , Corticosterona/sangue , Ciclo-Oxigenase 1/metabolismo , Ciclo-Oxigenase 2/metabolismo , Inibidores de Ciclo-Oxigenase 2/farmacologia , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Formaldeído , Inflamação/sangue , Inflamação/induzido quimicamente , Inflamação/enzimologia , Injeções Intraperitoneais , Injeções Subcutâneas , Masculino , Proteínas de Membrana/antagonistas & inibidores , Proteínas de Membrana/metabolismo , Camundongos , Dor/sangue , Dor/induzido quimicamente , Dor/enzimologia , Fitoterapia , Extratos Vegetais/administração & dosagem , Plantas Medicinais
7.
Pak J Biol Sci ; 16(19): 1016-21, 2013 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-24502164

RESUMO

In the present study, effects of hydro-alcoholic extract of Papaver rhoeas L. (Papaveraceae) on the metabolic changes induced by electro foot shock stress in male NMRI mice (25-30 g) has been investigated. The mice were received electric foot shock (40 mV) for 100 sec. Plasma corticosterone levels, food and water intake and delay to eating (Anorexia) were assessed 20 min later. Different doses of the plant extract (15, 30 and 60 mg kg(-1)), or saline (10 mL kg(-1)) was injected to the animals intraperitoneally 30 min before the stress. The control groups received saline (10 mL kg(-1)) or the extract (15, 30 and 60 mg kg(-1)) and 30 min later were exposed to the apparatus but did not received stress. Our results indicated that stress can increase plasma corticosterone level significantly and the extract can exacerbate the stress effect. However, stress could reduce food and water intake and increase delay to eating times which were inhibited by the extract pretreatment. The results indicate that administration of the extract of Papaver rhoeas can reduce the side effects of stress but increases plasma corticosterone level which may be due to its effects on the adrenal gland.


Assuntos
Papaver/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Estresse Psicológico/tratamento farmacológico , Estresse Psicológico/metabolismo , Animais , Corticosterona/sangue , Ingestão de Líquidos/efeitos dos fármacos , Ingestão de Alimentos/efeitos dos fármacos , Etanol/química , Feminino , Masculino , Camundongos , Estresse Psicológico/sangue
8.
Pak J Biol Sci ; 15(21): 1041-4, 2012 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-24163947

RESUMO

Stress amelioration can improve its metabolic as well as other side effects. In the present study, the effects of hydro-alcoholic extract of Papver rhoeas (L.) on formalin-induced pain and inflammation were investigated in male Swiss-Webster mice (20-25 g). Formalin injects in the plantar portion of mice hind paw and pain was studied for 60 min. The plant extract and other drugs were administered intraperitoneally 30 min before formalin. Experiments showed that administration of extract (25, 50 and 100 mg kg(-1)) could induced analgesia in a dose-response manner in both phases of formalin test. More over, the extract inhibits inflammation induced by formalin injection. Naloxone (4 mg kg(-1)), dextromethorphan (20 mg kg(-1)) and NG-nitro-L-arginine-methylester (L-NAME; 10 mg kg(-1)) reduced the extract analgesia in first but not late phase. Extract administration also increased plasma corticosterone level in dose-dependent manner. It could be concluded that Papaver rhoeas (L.) extract could inhibits acute phase of formalin test in mice by opioidergic, glutamatergic and nitricergic mechanisms. In addition, the extract can induce corticosterone plasma level which may be responsible for inhibition of inflammation and chronic phase of pain induced by formalin.


Assuntos
Analgésicos/farmacologia , Anti-Inflamatórios/farmacologia , Formaldeído , Inflamação/prevenção & controle , Dor/prevenção & controle , Papaver , Extratos Vegetais/farmacologia , Analgésicos/química , Analgésicos/isolamento & purificação , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/isolamento & purificação , Corticosterona/sangue , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Inflamação/sangue , Inflamação/induzido quimicamente , Masculino , Camundongos , Dor/sangue , Dor/induzido quimicamente , Medição da Dor , Papaver/química , Fitoterapia , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Plantas Medicinais , Fatores de Tempo
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