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1.
Polymers (Basel) ; 15(20)2023 Oct 20.
Article in English | MEDLINE | ID: mdl-37896419

ABSTRACT

This study investigates the feasibility of using biodegradable secondary alcohol ethoxylate (SAE) non-ionic surfactant as a building block for the formation of reverse micelles, functioning as reactive dye carriers for the dyeing of cotton fabric in non-aqueous octane medium. Ten dyeing parameters were optimised, by a one-factor-at-a-time approach, namely: (i) effect of colour fixation agent; (ii) surfactant-to-water mole ratio; (iii) surfactant-to-co-surfactant mole ratio; (iv) volume of soda ash; (v) volume of dye; (vi) solvent-to-cotton ratio; (vii) dyeing temperature; (viii) dyeing time; (ix) fixation time; (x) soda-ash-to-cotton ratio. The colour properties, fastness properties and physical properties of SAE-dyed samples were experimentally compared with the conventional water-dyed samples. The optimised condition was found when SAE samples were dyed as follows: (a) 1:20 surfactant-to-water ratio; (b) 1:8 surfactant-to-co-surfactant ratio; (c) 10:1 solvent ratio; (d) 40 min dyeing time; (e) 60 min fixation time; and (f) 70 °C dyeing and fixation temperature. The results showed that SAE-dyed samples have better colour strength, lower reflectance percentage and comparable levelness, fastness and physical properties than that of water-dyed samples. SEM images revealed that the dyed cotton fibres had no severe surface damage caused by an SAE-based reverse micellar dyeing system. The TEM image depicts that the reverse micelle was of nanoscale, spherical-shaped and had a core-shell structure, validating the presence of reverse micelle as a reactive dye carrier and the potential of an SAE-based reverse micellar system for dyeing of cotton fabrics.

2.
J Obstet Gynaecol Res ; 47(3): 904-912, 2021 Mar.
Article in English | MEDLINE | ID: mdl-33336450

ABSTRACT

AIM: To evaluate the effect of music in reducing pain during outpatient hysteroscopy under no anesthesia. METHODS: We conducted a prospective randomized controlled trial From June 2019 to December 2019 in Pamela Youde Nethersole Eastern Hospital in Hong Kong. A total of 107 patients were randomized to music group (n = 54) or non-music group (n = 53). Music was played during outpatient hysteroscopy in the music group. Patients in the non-music group had the procedure done in the same setting without music. Primary outcome was the level of pain measured using the visual analog scale (VAS) score before and during the procedure. Secondary outcomes were vital parameters that reflect the level of pain including blood pressure and heart rate. RESULTS: Patients in the music group experienced significantly less pain during outpatient hysteroscopy (VAS score 4.54 ± 2.89 vs 5.88 ± 2.90; P = 0.02). The anticipated pain level was similar in both groups (VAS score 5.59 ± 2.27 vs 6.11 ± 2.43; P = 0.27). There was no statistically significant difference between the two groups in all the vital parameters. CONCLUSION: Listening to music during outpatient hysteroscopy under no anesthesia significantly reduces pain in a well-matched Chinese population. Music is easy to provide with low-cost equipment and manpower. We recommend the routine use of music during outpatient hysteroscopy to improve patient care.


Subject(s)
Hysteroscopy , Music , Female , Hong Kong , Humans , Hysteroscopy/adverse effects , Outpatients , Pain , Pain Measurement , Pregnancy , Prospective Studies
3.
Front Psychol ; 8: 2036, 2017.
Article in English | MEDLINE | ID: mdl-29209260

ABSTRACT

The article explores undergraduate students' experiences of developing mindful agency as a positive learning disposition, their perceived change as a learner, and the possible impact of mindful agency coaching on students' learning and personal growth, using a narrative research method. Seventy Chinese undergraduate students generated personal reflective journals and eight participants' journals were selected to enter into the narrative-oriented inquiry. Our analysis revealed a number of primary themes based on which we produced a meta-story. The supplements of the story were exacted for further critical cross-case discussion. The finding indicated that the multifaceted development of mindful agency involved learning methods, emotional regulation, strategic thinking, and awareness of planning, openness to experience, self-acceptance and self-esteem, and learning engagement, with enhanced sense of personal awareness and awakening. The coaching was supportive for students to foster positive self-identities and become more reflective, mindful, and self-determined.

6.
J Phys Chem B ; 115(23): 7524-32, 2011 Jun 16.
Article in English | MEDLINE | ID: mdl-21591775

ABSTRACT

Interactions between cyclomaltoheptaose (ß-cyclodextrin, ßCD) and p-toluenesulfonyl chloride (TsCl) were investigated using MD simulations, both in vacuum, approximating the hydrophobic environment of the CD cavity, and with water as a solvent. In both cases, the minimum energy adiabatic paths, and the mean force potentials (MFP) for the insertion of TsCl along a reaction coordinate perpendicular to the CD plane, were calculated for the two possible orientations of TsCl. The results show a preferred entry of TsCl in the CD cavity with the sulfonyl chloride group pointing to the primary hydroxyls rim. In each orientation, two energy minima for the complex are detected in vacuum that reflect the H-H contacts between host and guest observed by NMR spectroscopy (ROESY, NOESY). These separate minima collapsed into a single broader minimum, when the solvent was introduced in the simulations. The resulting association constant between TsCl and ßCD (K(a) ≈ 100 M(-1)) is in good agreement with the NMR results (K(a) = 102 ± 12 M(-1)) in deuterated water solution at 298 K. Advantage has been taken of the dynamics of the reagent inclusion to set up a one step process involving a transient Cu(2+) chelate at the secondary hydroxyls rim position for the electrophilic monoactivation of ßCD at the primary hydroxyls rim using water as solvent.


Subject(s)
Copper/chemistry , Glucans/chemistry , Hydroxides/chemistry , Organometallic Compounds/chemistry , Tosyl Compounds/chemistry , Chelating Agents/chemistry , Cyclization , Hydrogen-Ion Concentration , Magnetic Resonance Spectroscopy , Models, Molecular , Molecular Dynamics Simulation , Stereoisomerism , Thermodynamics , Water
7.
Eur J Pharm Biopharm ; 61(1-2): 40-9, 2005 Sep.
Article in English | MEDLINE | ID: mdl-16000249

ABSTRACT

In addition to improving drug solubilization, cyclodextrins (CDs) also affect the biological behavior of the included compound. We evaluated the effects of two natural CDs beta-CD and gamma-CD, and six beta-CD derivatives, Dimeb, Trimeb, SBb, 2-HP, 6AD, and 6 MTU on the biological behavior of (99m)TcN-NOET, a technetium-99m-labeled, lipophilic compound readily detectable through radioactivity assessment. Determination of CDs' affinities for (99m)TcN-NOET indicated that the cavity size of gamma-CD was not suitable for (99m)TcN-NOET inclusion, and that beta-CD derivatization mostly resulted in decreased CDs affinities for (99m)TcN-NOET to various extents compared with the natural beta-CD. In vitro and ex vivo experiments performed on newborn rat cardiomyocytes and isolated perfused rat hearts, respectively, showed 1.7- and 2.3-fold maximal differences in (99m)TcN-NOET cellular and tissue activities. Regression analyzes indicated no significant correlation between these observed biological differences and the affinities of the eight CDs tested for (99m)TcN-NOET or for cellular membranes. In conclusion, CD derivatization often resulted in impaired affinity of the derivatives for the lipophilic compound (99m)TcN-NOET. Moreover, the in vitro and ex vivo biological behavior of (99m)TcN-NOET was greatly affected depending on the CD used for inclusion of the tracer.


Subject(s)
Cyclodextrins/chemistry , Heart/diagnostic imaging , Myocardium/metabolism , Myocytes, Cardiac/metabolism , Organotechnetium Compounds/pharmacokinetics , Thiocarbamates/pharmacokinetics , Animals , Animals, Newborn , Cyclodextrins/pharmacokinetics , Dogs , In Vitro Techniques , Linear Models , Male , Organotechnetium Compounds/chemistry , Radionuclide Imaging , Rats , Rats, Wistar , Solubility , Thiocarbamates/chemistry
9.
Carbohydr Res ; 338(5): 451-3, 2003 Feb 14.
Article in English | MEDLINE | ID: mdl-12559748

ABSTRACT

2(I)-O-p-Tolylsulfonylcyclomaltoheptaose was obtained in 42% yield by reaction of 1-(p-tolylsulfonyl)-(1H)-1,2,4-triazole on NaH-deprotonated cyclomaltoheptaose in DMF and further converted into the corresponding mono-2(I),3(I)-manno-epoxide.


Subject(s)
Cyclodextrins/chemistry , Triazoles/chemistry , beta-Cyclodextrins
10.
Bioorg Med Chem ; 10(8): 2759-65, 2002 Aug.
Article in English | MEDLINE | ID: mdl-12057665

ABSTRACT

The proposed phenyl-A region of sigma (sigma) receptors accommodates several structural features. In this study we explored the possibility that appropriate structural features located at the phenyl-A region of sigma receptor sites could lead to more potent and selective agents for the sigma receptor subtypes. By keeping the phenyl-B substituent as the optimum omega-phenylpentyl moiety, and varying substituents in the phenyl-A region, we have observed changes in binding potency and selectivity at the sigma receptor subtypes. SAR for the binding of these compounds at sigma-2 sites was also examined.


Subject(s)
Molecular Probes/chemical synthesis , Receptors, sigma/chemistry , Animals , Humans , Molecular Probes/metabolism , Piperidines/chemical synthesis , Piperidines/metabolism , Protein Binding , Radioligand Assay , Receptors, sigma/metabolism , Structure-Activity Relationship , Sigma-1 Receptor
11.
J Org Chem ; 67(11): 3637-42, 2002 May 31.
Article in English | MEDLINE | ID: mdl-12027674

ABSTRACT

Nucleophilic substitution of 2beta-mesyloxymethyl-N-methyl-3beta-p-tolyl-tropane intermediate with alkoxides, metal imides, or amines was found to lead not only to the expected bicyclo[3.2.1]octane (tropane) ether, imide, and amine derivatives but also to unexpected bicyclo[3.2.2]nonane derivatives. When alkoxides were used as nucleophile, only the rearranged bicyclo[3.2.2]nonane structure was obtained, whereas the use of amines or imides as nucleophile afforded a mixture of the two structures. The bicyclo[3.2.2]nonane structure was assigned by NMR analysis.


Subject(s)
Amines/chemical synthesis , Ethers/chemical synthesis , Imides/chemical synthesis , Tropanes/chemical synthesis , Alkanes/chemical synthesis , Aza Compounds/chemical synthesis , Bridged Bicyclo Compounds/chemistry , Magnetic Resonance Spectroscopy/methods , Mesylates/chemistry , Octanes/chemical synthesis , Tropanes/chemistry
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