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2021 ◽  
pp. 894-901
Author(s):  
Hamad. M. Adress. Hasan ◽  
Huda S. Muftah ◽  
Nada. Hemdan. Ahmed

This study which carried out on some indicators including (Phenol red and Bromo phenol Blue). Different solvents were used including (Methanol, propanol, DMF and DMSO). The effect of solvents on the λ max and absorbance values were investigated. The results recorded that the λmax values were effected and changed according to the polarities of the applied solvents. Also, the obtained results showed changes in the absorbance values after applied solvents compared with the original absorbance values. Keywords: Bromophenol blue; Phenol red; Effect of solvents on electronic transitions


2021 ◽  
pp. 339357
Author(s):  
Xianjuan Shen ◽  
Siyi Wang ◽  
Qian Lu ◽  
Yuehua Guo ◽  
Li Qian
Keyword(s):  

2021 ◽  
Vol 8 ◽  
Author(s):  
Tong Lin ◽  
Wushuang Wang ◽  
Yang Lu ◽  
Lan Gong

Background: Punctal/intracanalicular plugs on the market nowadays are all designed before clinical use in treating dry eye disease (DED). To provide an individualized lacrimal drainage system occlusion method and reduce the complications, we developed a “liquid plug” strategy by intracanalicular injection of hydroxybutyl chitosan (HBC) solution, a thermosensitive, phase-changing biomaterial. This study evaluated the efficacy and safety of the HBC plug in treating dry eye disease by comparing it with the VisiPlug absorbable intracanalicular plug.Methods: A monocenter, randomized, controlled clinical trial was performed. Fifty patients with DED were randomized 1:1 to undergo either the HBC injection treatment or the VisiPlug treatment. Ocular Surface Disease Index (OSDI) questionnaire, tear break-up time (TBUT), corneal fluorescence staining (CFS), tear meniscus height (TMH), and phenol red thread test were evaluated at Day 0 (baseline, before treatment) and Weeks 1, 4, and 12.Results: The two groups had a balanced baseline of age, gender, and DED-related characteristics. Both occlusion methods could relieve the symptoms and signs of DED. Significant improvement was found in OSDI, phenol red thread test, and tear meniscus height (P < 0.05 compared to baseline) but not in corneal fluorescence staining and tear break-up time (P > 0.05). There is no statistically significant difference between HBC injection and VisiPlug at Weeks 1 and 4 (P > 0.05). However, at week 12, the HBC injection was not as effective as the VisiPlug in maintaining phenol red thread test (HBC: 5.35 ± 3.22 mm, VisiPlug: 8.59 ± 4.35 mm, P = 0.009) and tear meniscus height (HBC: 206.9 ± 47.95 μm, VisiPlug: 242.59 ± 60.30 μm, P = 0.041). The numbers of ocular adverse events were relatively low in both groups.Conclusions: The HBC injection showed similar efficacy and safety compared to VisiPlug. The intracanalicular injection of HBC solution proves to be a promising, individualizing method to treat DED.Clinical Trial Registration: This study is registered with the Chinese Clinical Trial Registry (https://www.chictr.org.cn/enindex.aspx), Identifier: ChiCTR1800016603.


Author(s):  
Puteri Nur Syahirah Mohamed Mustafa ◽  
Aiman Shahmi Azam ◽  
Mohd Suhaimi Sulaiman ◽  
Ahmad Fairuz Omar ◽  
Mohamad Faizal Abd Rahman

<p>This paper proposed an optical pH measurement system developed to measure the changes of pH levels based on colorimetric reactions with phenol red reagent. The optical sensing was achieved through the implementation of a pair of light emitting diode (LED) and photodiode. The detection mechanism was based on different absorbance of light intensity at pH values of 2.36, 8.32, 9.08 and 12.83. The data processing method was carried out using LabVIEW software and interfaced with NI USB DAQ 6008. The measured voltage showed a good correlation in relation to the pH level with R2 equals to 0.9624. This relationship was used as a calibration curve in the final system testing. The final measurement of pH showed a good agreement between the actual and measured values with an error of less than 5%, thus indicating the reliability of the proposed system.</p>


Planta Medica ◽  
2021 ◽  
Author(s):  
Pedro Modesto Nascimento Menezes ◽  
Emanuella Chiara Valença Pereira ◽  
Kátia Simoni Bezerra Lima ◽  
Bismarques Augusto Oliveira da Silva ◽  
Mariana Coelho Brito ◽  
...  

Abstract Cannabis sativa is a millenary medicinal plant. However, contrary to worldwide paradigm-shifting, countries like Brazil still prohibit C. sativa cultivation and its medicinal use, even though many populations use aerial parts and roots of this plant for healthcare. As such, the objective of this work was to identify substances in the samples of the C. sativa roots, tracing a correlation with antitussive and expectorant effects. Therefore, samples of C. sativa roots were donated by the Polícia Federal Brasileira, and its aqueous extract (AECsR) was prepared with subsequent lyophilization, to maintain the material stability. After that, the material was analyzed by LC-MS to observe its chemical profile. Four samples (AECsR-A, B, C, and D) were tested in animal models of citric acid-induced cough (0.4 M) and phenol red expectoration (500 mg/kg). Using LC-MS it was possible to identify 5 molecules in C. sativa roots: p-coumaroyltyramine, tetrahydrocannabinol-C4, feruoiltyramine, anhydrocanabisativine, and cannabisativine. In experimental protocols, male mice (Mus musculus) were treated with samples of AECsR at doses of 12.5, 25, or 50 mg/kg regardless of the pharmacological test. In these tests, all samples showed the potential to treat cough and promote fluid expectoration, differing only in the dose at which these effects were observed. Therefore, the data showed that the C. sativa roots of the Brazilian Northeast showed antitussive and expectorant effects, even with intense secondary metabolitesʼ variation, which alters its potency, but not its effect. This highlights the importance of this medicinal plant for future therapy and corroborates to traditional use.


2021 ◽  
Vol 8 ◽  
Author(s):  
Miguel Delicado-Miralles ◽  
Enrique Velasco ◽  
Ariadna Díaz-Tahoces ◽  
Juana Gallar ◽  
M. Carmen Acosta ◽  
...  

Perfluorohexyloctane (F6H8) eyedrops have been recently introduced in Europe as a product to treat dry eye disease, based on its ability to reduce tear film instability in Meibomian gland dysfunction and evaporative dry eye disease, although its mechanism of action is still unknown. In the present pilot study, we evaluated the effects of the ocular instillation of a single drop of commercial F6H8 eyedrops in 20 healthy humans (9 women/11 men), measuring: (a) Corneal surface temperature (CST) from infrared video images; (b) tear volume using phenol red threads; (c) blinking frequency; and (d) ocular surface sensations (cold, dryness, pricking, foreign body, burning, itching, gritty, eye fatigue, watering eyes, and light-evoked discomfort sensations; scored using 10 cm Visual Analog Scales), before and 5–60 min after F6H8 or saline treatment. CST decreased and tearing and blinking frequency increased significantly after F6H8 but not after saline solution. When applied unilaterally, CST decreased only in the F6H8-treated eye. No sensations were evoked after F6H8 or saline. The corneal surface temperature reduction produced by topical F6H8 does not evoke conscious ocular sensations but is sufficient to increase the activity of corneal cold thermoreceptors, leading to an increased reflex lacrimation and blinking that may relieve dry eye condition thus reducing ocular discomfort and pain.


Animals ◽  
2021 ◽  
Vol 11 (10) ◽  
pp. 2987
Author(s):  
Samanta Nardi ◽  
Federico Puccini Leoni ◽  
Viola Monticelli ◽  
Valentina Virginia Ebani ◽  
Fabrizio Bertelloni ◽  
...  

Given the abundance of chickens in Italy, it is important for veterinarians to know the normal state of chickens’ eyes in order to identify any ophthalmic pathological changes. The aim of this study was to determine the normal values of select ocular parameters and to evaluate conjunctival microflora in two Italian chicken breeds. Sixty-six healthy chickens underwent a complete ophthalmic examination, which included a phenol red thread test (PRTT) for the evaluation of tear production and the assessment of intraocular pressure by rebound tonometry. B-mode ultrasound biometric measurements and conjunctival microflora identification were also performed in twenty-seven chickens. Mean PRTT was 23.77 ± 2.99 mm/15 s in the Livorno breed and 19.95 ± 2.81 mm/15 s in the Siciliana breed. Mean intraocular pressure was 14.3 ± 1.17 mmHg in the Livorno breed and 14.06 ± 1.15 mmHg in the Siciliana breed. Reference ranges for morphometric parameters were reported in the two breeds. Twenty-three chickens (85.18%) were bacteriologically positive. Chlamydia spp. antigen was detected in 14.81% of chickens. No positive cultures were obtained for fungi. Normal reference range values for selected ophthalmic parameters were obtained in clinically healthy chickens, which could facilitate accurate diagnosis and better management of ophthalmic diseases in these animals.


Author(s):  
Harjeet Singh ◽  
Shweta Sao

L-asparaginase (EC 3.5.11. L-asparagine amidohydrolase) is first enzyme, studied very intensively in human beings with regard to its anti-tumor potential against tumor of lymphoid precursor, acute lymphoblastic leukemia (ALL). The current drugs are suffering from many side effects like immune suppression, infertility, secondary neoplasm. The immunogenic complications associated with its present microbial sources Escherichia coli; Erwinia carotovora limits its medicinal frontier. So there exists a need of switching to novel natural sources to serve as non-immunogenic and better production sources of L-asparaginase. In the present study, four cultures of fungal endophytes viz. TSF-1, TSF-2, TSF-3 and TSF-4 selected on the basis of primary and secondary screening was carried on with L-asparagine as a sole carbon and nitrogen source and phenol red as pH indicator. The maximum protein content was observed to be present in TSF-2 i.e. 2.727 mg /mL and possessed maximum activity of 6.054 Units/ml. Sample was separated by SDS-PAGE, stained by silver staining, showed a single band with molecular weight of approximately ~45kDa.


Author(s):  
Concepción De-Hita-Cantalejo ◽  
María Carmen Sánchez-González ◽  
Carmen Silva-Viguera ◽  
Marta C. García-Romera ◽  
Ricardo Feria-Mantero ◽  
...  

Abstract Purpose To study the treatment efficacy of hyaluronic acid 0.3%, cyanocobalamin (vitamin B12), electrolytes, and P-Plus in menopausal patients with moderate dry eye disease. Methods Thirty female patients of mean age 53.06 ± 5.20 years (45–65) were enrolled in this prospective longitudinal study. Meibomian gland loss assessment was determined using a scale with four levels. The Ocular Surface Disease Index (OSDI) questionnaire, phenol red thread (PRT) test, and tear film break-up time (TFBUT) were also completed by the patients. Tear eye drops were formulated with 0.3 g of sodium hyaluronate, P-Plus ™, vitamin B12, sodium chloride, potassium chloride, calcium chloride, magnesium chloride, and SCO® (stabilized complex oxychloride). After 30 days, the patients were re-evaluated. Results The mean meibomian gland loss percentage was 37.97 ± 19.02 % (7.20 to 88.30%). Before treatment, the OSDI was 22.53 ± 14.03 score points (6.25 to 77.08). Posterior OSDI decreased to 16.26 ± 13.69 score points (0.00 to 70.83) (W = 58.00, P < 0.01). Before treatment, PRT was 10.31 ± 4.48 mm (4.00 to 21.00). Posterior PRT increased to 15.41 ± 6.27 mm (4.00 to 21.00) (W = 1520.50, P < 0.01). Before treatment, TFBUT was 6.23 ± 1.75 s (3.00 to 9.00). The posterior TFBUT increased to 8.10 ± 2.06 s (4.00 to 14.00) (W= 1382.50, P < 0.01). Conclusion The hyaluronic acid 0.3% and vitamin B12 eye drops effectively decreased dry eye symptoms in menopausal women and improved tear stability and volume.


2021 ◽  
Vol 12 ◽  
Author(s):  
Seung-Ju Hwang ◽  
Jing-Hua Wang ◽  
Jin-Seok Lee ◽  
Hwa-Dong Lee ◽  
Tae-Joon Choi ◽  
...  

Background: Yeokwisan, a standardized herbal formula, has exhibited clinical benefit for patients suffering from refractory functional dyspepsia (FD) in Korea since 2016. However, data about the mechanism of action of this formula are yet not available.Aim of the study: To evaluate and explore the effects of Yeokwisan on gastric emptying, a major symptom of functional dyspepsia, and its underlying mechanisms of action using a mouse model.Materials and methods: BALB/C mice were pretreated with Yeokwisan (100, 200, and 400 mg/kg, po) or mosapride (3 mg/kg, po) for 5 days and then treated with loperamide (10 mg/kg, ip) after 20 h of fasting. A solution of 0.05% phenol red (500 μL) or diet of 5% charcoal (200 μL) was orally administered, followed by assessment of gastric emptying or intestinal transit. Plasma acyl-ghrelin (ELISA), C-kit (immunofluorescence and western blotting), nNOS (western blotting) and gastric contraction- and ghrelin-related gene/protein expression levels were examined in stomach and small intestine tissues.Results: Loperamide injection substantially delayed gastric emptying, while Yeokwisan pretreatment (especially 200 and 400 mg/kg Yeokwisan) significantly attenuated this peristaltic dysfunction, as evidenced by the quantity of phenol red retained in the stomach (p &lt; 0.05 or 0.01) and stomach weight (p &lt; 0.05 or 0.01). The levels of plasma acyl-ghrelin and expression of gastric ghrelin-related genes, such as growth hormone secretagogue receptor (GHSR), ghrelin-O-acyltransferase (GOAT), adrenergic receptor β1 (ADRB1) and somatostatin receptor (SSTR), were significantly normalized (p &lt; 0.05 or 0.01) by Yeokwisan (400 mg/kg). Yeokwisan (400 mg/kg) significantly tempered the loperamide-induced alterations in the c-kit and nNOS levels (p &lt; 0.01) as well as the expression of contraction- and ghrelin-related genes, such as 5-HT4 receptor (5-HT4R), anoctamin-1 (ANO1), ryanodine receptor 3 (RYR3) and smooth muscle myosin light chain kinase (smMLCK), in the stomach, but not in the small intestine.Conclusion: The present results showed the clinical relevance of Yeokwisan, in treating FD, especially in promoting gastric emptying but not small intestinal transit. The main mechanisms corresponding to these effects may involve the modulation of the ghrelin pathway and activation of interstitial cells of Cajal in stomach tissue.


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