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1.
J Chem Neuroanat ; 114: 101956, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33831513

RESUMO

Noise-induced hearing loss (NIHL) is the second most common cause of acquired hearing loss. Acoustic trauma can cause oxidative damage in the cochlear hair cells (HCs) through apoptotic pathways. Apelin is a newly discovered neuropeptide with neuroprotective effects against the oxidative stress in neurodegenerative disorder. We investigated the preventive effects of apelin-13 on the cochlear HCs and spiral ganglion neurons (SGNs) against acoustic trauma via Sirtuin-1 (Sirt-1) regulation in rats. Animals were assigned to control, control + apelin-13 (50 or 100 µg/kg, ip), and noise exposure groups without any treatment or were administered apelin-13 (50 or 100 µg/kg, ip) and EX-527 (an inhibitor of Sirt-1) prior to each noise session. In the noise groups, 110 dB white noise was applied for 6 h per 5 days. Pre- and post-exposure distortion product otoacoustic emissions (DPOAE) and cochlear superoxide dismutase (SOD) activity were assessed. Western blot evaluated the cochlear protein expressions of Sirt-1, cleaved-caspase-3, Bax, and Bcl-2. Cell apoptosis was detected through TUNEL staining. Immunofluorescence was used to examine expression of HCs and SGNs specific protein. DPOAE level were significantly improved in the noise exposure group receiving 100 µg/kg apelin-13. At high doses, apelin augmented SOD levels in the rat cochlea subjected to noise. Apelin 100 markedly increased Sirt-1, and decreased cleaved- caspase-3 expression as well as Bax/Bcl-2 ratio in the cochlea tissue of noise-exposed rats. These findings suggest the promising therapeutic potential of apelin-13 for the prevention of noise-induced injury to cochlea and hearing loss.


Assuntos
Cóclea/efeitos dos fármacos , Perda Auditiva Provocada por Ruído/patologia , Peptídeos e Proteínas de Sinalização Intercelular/farmacologia , Fármacos Neuroprotetores/farmacologia , Sirtuína 1/biossíntese , Animais , Apoptose/efeitos dos fármacos , Cóclea/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Perda Auditiva Provocada por Ruído/metabolismo , Masculino , Ratos , Ratos Wistar
2.
Physiol Mol Biol Plants ; 26(3): 605-616, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32205934

RESUMO

Ultraviolet radiation induces biochemical and genetic changes in plants. The aim of this study was to investigate the effects of UV-B radiation on genetic stability, phenolic compounds and antioxidant activity of Pelargonium graveolens L'Her. Plant cuttings were exposed to 0, 0.12. 0.26 and 0.38 W/m2 of UV-B radiation. Results indicated that by increasing the UV-B radiation intensity, total phenols, flavonoids and anthocyanin contents, Phenylalanine ammonia lyase activity and antioxidant capacity were increased. Analysis of four flavonols (quercetin, myricetin, kaempferol and rutin) contents of leaves extract by HPLC indicated that these four flavonols were enhanced in all treated plants and also the ratio of quercetin to kaempferol (Q/K) showed a significant increase (P ≤ 0.05) in UV-B treated plants in compare to control. To evaluate the genetic variation in treated plants, 10 ISSR primers were used. The highest level of percentage of polymorphism (P%), Shannon index (I), number of effective allele (Ne) and Nei' genetic diversity (He), were observed at the highest UV-B radiation (0.38 W/m2). The AMOVA analysis also showed a significant genetic differentiation (P ≥ 0.001) among the studied groups, and confirmed the differentiation of groups obtained by the cluster analysis of molecular data. Overall, these results showed that biochemical changes in different intensities of UV-B were in line with genetic variations, so that the highest biochemical and genetic variations were observed in 0.38 W/m2 treatment.

3.
Physiol Mol Biol Plants ; 25(6): 1445-1456, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31736547

RESUMO

The electromagnetic fields (EMFs) by wide range of the frequency spectrum, have capability to cause crucial alternation and deleterious effects in biological systems. The aim of the present study is to assay the biochemical components, enzymatic and non-enzymatic antioxidant systems of the electromagnetic fields treated samples of tea which is the most ancient non-alcoholic drink, containing different types of flavonols. Rutin, Quercetin, Myricetin, and Kaempferol as flavonoid components markers are also to be analyzed using high-performance liquid chromatography. The results show that The EMF's treatments brought about distinct alternations in biochemical components of tea, so that regardless of the intensity of the EMF's, less duration of exposure (30 min) caused more content of those mentioned flavonoid components (except Myricetin) than that of 60 min of exposure. A 30 min of 4 miliTesla (mT) exposure of the EMF's, resulted in the highest amount of Rutin, Quercetin, Myricetin, and Kaempferol. It is concluded that less duration of the EMF's treatments induces more production and also accumulation of enzymatic and non-enzymatic antioxidant components. In higher intensity of the EMF's (more than 4 mT), the concentrations of the mentioned biochemical components decreased.

4.
Nanotechnol Sci Appl ; 12: 3-10, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31406458

RESUMO

PURPOSE: Evaluation of structural features, thermodynamics and kinetic properties of carbon nanofibers (CNFs) as artificial nanoscale enzymes (nanozyme). METHODS: Synthesis of CNFs was done using chemical vapor deposition, and transmission electron microscopy (TEM), field emission scanning electron microscopy (FE-SEM) and energy-dispersive x-ray spectroscopy (EDX) were used to provide information on the morphology, elemental monitoring and impurity assay of the CNFs. The thermal features of the CNFs were evaluated using differential thermal analysis (DTA), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA) derivative and TGA. The calculated thermo-physical parameters were melting temperature (Tm), weight loss maximum temperature (Tmax ) and enthalpy of fusion (ΔHfusion ). Catalytic activity was assayed by a 4-aminoantypyrine (4-AAP)-H2O2 coupled colorimetric system by UV-visible spectroscopy. RESULTS: FE-SEM and TEM analysis demonstrated parallel graphitic layers and uniformity of atomic orientation and morphology. The EDX spectra approved carbon element as major signal and presence of partial Ti as impurities of CNFs during CVD process. The DTA thermogram showed the endothermic process had a maximum temperature of 82.27°C at -15.48 mV and that thermal decomposition occurred at about 200°C. The TGA-differential gravimetric analysis thermogram showed that Tmax was 700°C. The DSC heat flow curve showed a melting temperature (Tm) of 254.52°C, ΔHfusion of 3.84 J^.g-1, area under the curve of 58.58 mJ and Te (onset) and Tf (end set) temperatures of 246.60°C and 285.67°C, respectively. The peroxidase activity of the CNFs obeyed the Michaelis-Menten equation with a double-reciprocal curve and the calculated Km, Kcat and Vmax kinetic parameters. CONCLUSION: CNFs as peroxidase nanozymes are intrinsically strong and stable nanocatalysts under difficult thermal conditions. The peroxidase activity was demonstrated, making these CNFs candidates for analytical tools under extreme conditions.

5.
Emerg (Tehran) ; 5(1): e56, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28894772

RESUMO

INTRODUCTION: Caustic ingestions are among the most prevalent causes of toxic exposure. The present 10-year survey aimed to evaluate the epidemiologic features and outcomes of caustic ingestion cases presenting to emergency department. METHODS: This is a retrospective cross-sectional study on patients who were admitted to a referral toxicology center during 2004 to 2014, following caustic ingestion. Baseline characteristics, presenting chief complaint, severity of mucosal injury, complications, imaging and laboratory findings as well as outcomes (need for ICU admission, need for surgery, mortality) were recorded, reviewing patients' medical profile, and analyzed using SPSS 22. RESULTS: 348 patients with mean age of 37.76 ± 17.62 years were studied (55.6% male). The mean amount of ingested caustic agent was 106.69 ± 100.24 mL (59.2 % intentional). Intentional ingestions (p < 0.0001), acidic substance (p = 0.054), and higher volume of ingestion (p = 0.021) were significantly associated with higher severity of mucosal damage. 28 (8%) cases had died, 53 (15.2%) were admitted to ICU, and 115 (33%) cases underwent surgery. CONCLUSION: It seems that, suicidal intention, higher grade of mucosal injury, higher volume of ingestion, lower level of consciousness, lower serum pH, and higher respiratory rate are among the most important predictors of need for ICU admission, need for surgery, and mortality.

6.
Acta Neurol Belg ; 117(1): 245-249, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27530310

RESUMO

Myasthenia gravis (MG) is one of the curable neurologic disorders. Various pharmacological therapies are administered for these patients and a thymectomy plays an important role in the therapy of myasthenia gravis, which develops a permanent or relative remission. We investigated the efficacy of intravenous immunoglobulin (IVIG) and plasma exchange (PLEX) as a preparation before thymectomy in patients with MG. This randomized clinical trial was conducted on 24 patients with MG referred for thymectomy, which were randomized to two groups of IVIG and PLEX. The IVIG group received IVIG 1 g/kg/day for two consecutive days and the PLEX group underwent 1-L plasma exchange five times with 5 % albumin replacement fluid, every other day, 10-30 days before the procedure. The duration of hospitalization (day), length of intensive care unit (ICU) stay after surgery (day), length of intubation period (h), duration of surgery (h) and dose of steroid administered were compared between the two groups. Analysis was performed via SPSS version 20. In the PLEX group, post-operative outcomes (duration of hospitalization, ICU length of stay after surgery, intubation period and duration of surgery) were longer than those in the IVIG group. There was significant difference in intubation period (p value = 0.01) and duration of surgery (p value = 0.05) between the PLEX and IVIG groups. The administration of IVIG in comparison to PLEX can be more effective in the preparation before thymectomy in myasthenia gravis patients.


Assuntos
Imunoglobulinas Intravenosas/uso terapêutico , Miastenia Gravis/terapia , Terapia Neoadjuvante/métodos , Troca Plasmática/métodos , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Timectomia , Resultado do Tratamento
7.
Gastroenterol Hepatol Bed Bench ; 9(3): 158-73, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27458508

RESUMO

Metabolome analysis is used to evaluate the characteristics and interactions of low molecular weight metabolites under a specific set of conditions. In cirrhosis, hepatocellular carcinoma, non-alcoholic fatty liver disease (NAFLD) and non-alcoholic steatotic hepatitis (NASH) the liver does not function thoroughly due to long-term damage. Unfortunately the early detection of cirrhosis, HCC, NAFLD and NASH is a clinical problem and determining a sensitive, specific and predictive novel method based on biomarker discovery is an important task. On the other hand, metabolomics has been reported as a new and powerful technology in biomarker discovery and dynamic field that cause global comprehension of system biology. In this review, it has been collected a heterogeneous set of metabolomics published studies to discovery of biomarkers in researches to introduce diagnostic biomarkers for early detection and the choice of patient-specific therapies.

8.
Medicine (Baltimore) ; 95(19): e3656, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27175693

RESUMO

The incidence of smuggling and transporting illegal substances by internal concealment, also known as body packing, is on the rise. The clinical approach to such patients has been changed significantly over the past 2 decades. However, despite a recorded increase in body packing in general, there are controversies in the management of these patients. We aimed to gather data regarding the demographic characteristics, treatment, and outcome of body packers, which were that referred to Loghman Hakim Hospital, Tehran, Iran.The data of all body packers admitted to Loghman Hakim Hospital during 2010 to 2014 were evaluated retrospectively. Data regarding the demographic characteristics of the patients, findings of clinical imaging, treatment, and outcome were recorded.In this study, 175 individuals with a mean age of 31 ±â€Š10 years were assessed. The most common concealed substances were crack (37%), crystal (17%), opium (13%), and heroin (6%). According to the results of surgery and imaging (abdominal radiography or computed tomography), the most common place for concealment was stomach in 33.3% and 12% of cases, respectively. Imaging findings were normal in 18% of the individuals. Forty-eight (27%) patients underwent surgery. The main indications for surgery were clinical manifestations of toxicity (79%) and obstruction of the gastro-intestinal tract (17%). The most common surgical techniques were laparotomy and gastrotomy (50%). The mean duration of hospitalization was 3.8 ±â€Š4 days. The mortality rate was 3%.Conservative treatment of body packers seems to be the best treatment method. Careful monitoring of the patients for possible signs and symptoms of intoxication and gastro-intestinal obstruction is strongly recommended.


Assuntos
Gerenciamento Clínico , Tráfico de Drogas , Corpos Estranhos/epidemiologia , Drogas Ilícitas , Estômago/cirurgia , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Estudos Transversais , Feminino , Corpos Estranhos/etiologia , Corpos Estranhos/terapia , Trato Gastrointestinal/cirurgia , Hospitalização/estatística & dados numéricos , Humanos , Irã (Geográfico)/epidemiologia , Masculino , Pessoa de Meia-Idade , Encaminhamento e Consulta , Estudos Retrospectivos , Adulto Jovem
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