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1.
Anal Chim Acta ; 1287: 342087, 2024 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-38182342

RESUMEN

In this study, a fully-featured electrochemiluminescence (ECL) sensing platform based on a multichannel closed bipolar system (closed-BP, C-BP) for the determination of caffeic acid (CA) was successfully developed. The system comprises three individual reservoirs connected to each other by two pairs of gold rods as bipolar electrodes. Moreover, a single pair of gold rods functions as the driving electrodes. Due to configuration consisting of three channels and double-bipolar electrodes, the detection of CA was accomplished in two oxidation and reduction pathways within a single device. Firstly, through close observation of the reactions occurring within the device and utilizing a universal pH indicator and bipolar electrodes, a precise mechanism for the current bipolar systems was initially proposed. Then, the concentration of CA was monitored in the reporting chamber through the following ECL intensities resulting from luminol oxidation and H2O2. The monitoring process was performed using both a photomultiplier tube (PMT) and a digital camera. In the process of analyte oxidation, the PMT and visual (camera)-based detection exhibited a linear response from 5 µmol L-1 to 700 µmol L-1 (limit of detection (LOD) 1.2 µmol L-1) and 50 µmol L-1 to 600 µmol L-1 (LOD 14.8 µmol L-1), respectively. In the analyte reduction pathway, the respective values were 30 µmol L-1 to 450 µmol L-1 (LOD 8.6 µmol L-1) and 55 µmol L-1 to 400 µmol L-1 (LOD 21.2 µmol L-1), for the PMT and visual-based detection, respectively. Our experiments have demonstrated the practical application of the sensor array for efficient and high-performance analysis. This innovative design holds significant potential for diverse fields and paves the way for the development of a user-friendly device.

3.
Iran J Pathol ; 17(3): 323-327, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36247497

RESUMEN

Background & Objective: Iron deficiency before birth or in infancy can cause long-term behavioral and neurological disorders. Measuring serum ferritin is an effective way to diagnose iron deficiency but requires significant blood volume from a low birth weight infant. Therefore, the present study was performed to investigate the relationship between serum and urinary ferritin levels in low birth weight infants. Methods: In this cross-sectional study, 76 infants weighing less than 2500 g were studied. To measure serum ferritin level, 1.5 mL of blood and to measure urinary ferritin level, at least 1 mL of urine was collected from each infant. Then the results were compared. Data analysis was performed using SPSS software version 16, and the significance level was considered less than 0.05. Results: Out of 76 neonates studied, 51.3% were boys, and 80.3% were premature infants. The mean birth weight of infants was 2056.31±318.74 g, and the mean serum and urinary ferritin levels were 134.77±72.35 and 85.55±70.97 ng, respectively. There was a statistically significant relationship between serum and urinary ferritin levels. Also, serum ferritin and urinary ferritin levels had a statistically significant relationship with birth weight and gestational age. The higher the birth weight as well as the age at birth, the higher the serum ferritin and urinary ferritin. Conclusion: According to the findings of this study, measurement of urinary ferritin level can be used as a noninvasive tool for iron deficiency screening in low birth weight infants instead of serum ferritin level.

4.
Clin Exp Pediatr ; 65(4): 188-193, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-34325499

RESUMEN

BACKGROUND: Respiratory distress syndrome (RDS) is a common cause of hospitalization and death in preterm infants who require surfactant treatment and respiratory support. PURPOSE: This study aimed to compare the clinical outcomes of minimally invasive surfactant therapy (MIST) and the INtubation, SURfactant administration, and Extubation (INSURE) technique in preterm infants with RDS. METHODS: In this clinical trial, 112 preterm infants born at 28-36 weeks of gestation and diagnosed with RDS randomly received 200-mg/kg surfactant by MIST or the INSURE method. In the MIST group, surfactant was administered using a thin catheter (5F feeding tube); in the INSURE group, surfactant was administered after intubation using a feeding tube and the tracheal tube was removed after positive pressure ventilation was started. Nasal continuous positive airway pressure was applied in both groups for respiratory support and the postprocedure clinical outcomes were compared. RESULTS: The mean hospitalization time was shorter for infants in the MIST group than for those in the INSURE group (9.19± 1.72 days vs. 10.21±2.15 days, P=0.006). Patent ductus arteriosus was less frequent in the MIST group (14.3% vs. 30.4%, P=0.041). Desaturation during surfactant administration occurred less commonly in the MIST group (19.6% vs. 39.3%, P=0.023). There were no significant intergroup differences in other early or late complications. CONCLUSION: These results suggest that surfactant administration using MIST could be a good replacement for INSURE in preterm infants with RDS since its use reduced the hospitalization time and the number of side effects.

5.
BMC Nutr ; 7(1): 55, 2021 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-34593026

RESUMEN

BACKGROUND: Todays, due to the impact of human food choices on increasing greenhouse gas emissions, water consumption and environmental degradation, there is a new approach about changing the pattern of food production and consumption, including sustainable food and nutrition system related to consumption. This study aimed to explore the components of a sustainable diet among the factors that affect people's food choices. METHODS: This qualitative study was carried out using an in-depth interview with 33 individuals aged 30-64 years old living in different areas of Tehran. Data collection, data analysis and theoretical conceptualization were performed simultaneously. MAXQDA 10 software was used for managing and organizing the data. RESULTS: In this paper, the findings are categorized according to the key components of a sustainable diet in five themes: "Health and Nutrition", "Food and Agriculture Security", "Environment and Ecosystems", "Markets, food trade and production chains", "social, cultural, and policy factors" were categorized. Meanwhile, the components of the "Health and Nutrition" domain had the highest contribution and the components of the two domains "food and agriculture" and "environment and ecosystems" had the lowest role based on the participants' perception in this study. CONCLUSION: Considering to the low importance of the components of a sustainable diet in food choices of the community, promoting the individual awareness of sustainable diet components, clarifying the importance of food choices in creating environmental impacts and leading the national macro policies in the field food and nutrition toward sustainable diet goals are essential.

6.
Langmuir ; 37(26): 7975-7985, 2021 07 06.
Artículo en Inglés | MEDLINE | ID: mdl-34170134

RESUMEN

The interactions of mono-rhamnolipids (mono-RLs) with model membranes were investigated through a biomimetic approach using phospholipid-based liposomes immobilized on a gold substrate and also by the multiparametric surface plasmon resonance (MP-SPR) technique. Biotinylated liposomes were bound onto an SPR gold chip surface coated with a streptavidin layer. The resulting MP-SPR signal proved the efficient binding of the liposomes. The thickness of the liposome layer calculated by modeling the MP-SPR signal was about 80 nm, which matched the average diameter of the liposomes. The mono-RL binding to the film of the phospholipid liposomes was monitored by SPR and the morphological changes of the liposome layer were assessed by modeling the SPR signal. We demonstrated the capacity of the MP-SPR technique to characterize the different steps of the liposome architecture evolution, i.e., from a monolayer of phospholipid liposomes to a single phospholipid bilayer induced by the interaction with mono-RLs. Further washing treatment with Triton X-100 detergent left a monolayer of phospholipid on the surface. As a possible practical application, our method based on a biomimetic membrane coupled to an SPR measurement proved to be a robust and sensitive analytical tool for the detection of mono-RLs with a limit of detection of 2 µg mL-1.


Asunto(s)
Liposomas , Resonancia por Plasmón de Superficie , Decanoatos , Fosfolípidos , Ramnosa/análogos & derivados
7.
Med J Islam Repub Iran ; 35: 192, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-36042828

RESUMEN

Background: Severe indirect hyperbilirubinemia causes neurotoxicity, leading to potential permanent injuries to the neonatal nervous system. The present study intended to compare the effectiveness and complications of Single-Surface Intensive Phototherapy (SSIP) and Double-Surface Intensive Phototherapy (DSIP) in treating non-hemolytic hyperbilirubinemia in the neonatal ward of the Besat Hospital, Hamadan, Iran. Methods: In this prospective randomized clinical trial, 150 healthy full-term neonates born between 37-42 weeks gestation with ages <14 days old and birth weights ≥2500 gr who were affected by non-hemolytic hyperbilirubinemia with total serum bilirubin of 15-20 mg/dL were randomly allocated to two groups. Each group (n=75) underwent either SSIP or DSIP. Demographics, bilirubin level alterations, weight, platelet count, number of defecation per day, and body temperature of the patients were monitored and recorded in a specific questionnaire. Data analysis was performed using SPSS version 26.0 software, with the Chi-square and independent t-test. Results: The pre-intervention levels of indirect bilirubin were 17.07±1.46 mg/dL in the SSIP group and 17.10±1.54 mg/dL in the DSIP group (P-value = 0.853). After 24 and 48 hours of treatment, the mean indirect bilirubin level of the SSIP group reduced to 13.12±1.71 mg/dL and 9.69±1.68 mg/dL, respectively. In the DSIP group, the levels were 11.85±2.17 mg/dL and 8.43±1.56 mg/dL after 24 and 48 hours of treatment, respectively. The absolute reductions of indirect bilirubin were 7.76±3.28 mg/dL for the SSIP group and 8.96±4.49 mg/dL for the DSIP group (P-value = 0.458). Therefore, the indirect bilirubin levels were significantly different between the groups after 24 and 48 hours of treatment and at the time of discharge (P<0.05). There were no significant inter-group differences in weight, platelet count, and incidence of skin rash, while the number of defecation and body temperature were higher in the DSIP group (P <0.05). However, body temperature alterations had no clinical relevance. Conclusion: Compared to the SSIP, the DSIP showed faster effectiveness and led to a shorter hospital stay, while it did not entail higher levels of complications.

8.
Materials (Basel) ; 12(4)2019 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-30813395

RESUMEN

Graphene-based materials are widely studied to enable significant improvements in electroanalytical devices requiring new generations of robust, sensitive and low-cost electrodes. In this paper, we present a direct one-step route to synthetize a functional nitrogen-doped graphene film onto a Ni-covered silicon electrode substrate heated at high temperature, by pulsed laser deposition of carbon in the presence of a surrounding nitrogen atmosphere, with no post-deposition transfer of the film. With the ferrocene methanol system, the functionalized electrode exhibits excellent reversibility, close to the theoretical value of 59 mV, and very high sensitivity to hydrogen peroxide oxidation. Our electroanalytical results were correlated with the composition and nanoarchitecture of the N-doped graphene film containing 1.75 at % of nitrogen and identified as a few-layer defected and textured graphene film containing a balanced mixture of graphitic-N and pyrrolic-N chemical functions. The absence of nitrogen dopant in the graphene film considerably degraded some electroanalytical performances. Heat treatment extended beyond the high temperature graphene synthesis did not significantly improve any of the performances. This work contributes to a better understanding of the electrochemical mechanisms of doped graphene-based electrodes obtained by a direct and controlled synthesis process.

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