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1.
Nanomaterials (Basel) ; 12(17)2022 Sep 05.
Article in English | MEDLINE | ID: mdl-36080115

ABSTRACT

The reaction time, temperature, ratio of precursors, and concentration of sodium citrate are known as the main factors that affect the direct synthesis process of SiO2@Au based on the chemical reaction of HAuCl4 and sodium citrate. Hence, we investigated, in detail, and observed that these factors played a crucial role in determining the shape and size of synthesized nanoparticles. The significant enhancement of the SERS signal corresponding to the fabrication conditions is an existing challenge. Our study results show that the optimal reaction conditions for the fabrication of SiO2@Au are a 1:21 ratio of HAuCl4 to sodium citrate, with an initial concentration of sodium citrate of 4.2 mM, and a reaction time lasting longer than 6 h at a temperature of 80 °C. Under optimal conditions, our synthesis process result is SiO2@Au nanoparticles with a diameter of approximately 350 nm. In particular, the considerable enhancement of Raman intensities of SiO2@Au compared to SiO2 particles was examined.

2.
Drug Deliv ; 29(1): 882-888, 2022 Dec.
Article in English | MEDLINE | ID: mdl-35277106

ABSTRACT

PURPOSE: Rheumatoid arthritis, a chronic and progressive inflammation condition in the joints, has significantly reduced the patient quality of life and life expectancy. Crucially, there is no complete therapy for this disease, and the current treatments possess numerous side effects. Thus, novel therapeutic approach is necessary. To that end, this study developed novel silk fibroin in-situ hydrogel containing Sesbania sesban L. extract, a plant with high anti-inflammatory actions that are beneficial for rheumatoid arthritis treatments. METHODS: The hydrogels were manufactured using simple method of spontaneous gelation at different temperature. The gel properties of morphology, gelation time, viscosity, gel strength, stability, drug loading capacity, drug release rate, and in-vitro anti-inflammatory activity were investigated with appropriate methods. RESULTS: The optimal formulation had highly porous structure, with a gelation time of 0.5 h at room temperature and bodily temperature of 37 °C, a viscosity of 2530 ± 50 cP, a gel strength of 1880.14 ± 35.10 g, and a physical stability of >6 months. Moreover, the hydrogel contained the Sesbania sesban L. leaf extract with a total phenolic content of 92.8 ± 8.30 mg GAE/g, and sustained the release rate for >20 days, followed the Higuchi model. Regarding the in-vitro activities, all formulations were nontoxic to the RAW 264.7 cell line and demonstrated comparable anti-inflammatory activity to the free extract, in terms of the NO reduction levels. CONCLUSION: Conclusively, the systems possessed potential properties to be further investigated to become a prospective rheumatoid arthritis treatment.


Subject(s)
Arthritis, Rheumatoid , Fibroins , Hydrogels , Plant Extracts/therapeutic use , Sesbania , Arthritis, Rheumatoid/drug therapy , Drug Carriers/chemistry , Fibroins/chemistry , Humans , Hydrogels/chemistry , Plant Extracts/administration & dosage , Prospective Studies , Quality of Life , Sesbania/chemistry
3.
Heliyon ; 7(1): e05872, 2021 Jan.
Article in English | MEDLINE | ID: mdl-33521345

ABSTRACT

The Red River Delta is considered one of the largest megadelta systems in Asia. The formation of this delta has been controlled by the continent-ocean interaction and sea-level fluctuation during the Cenozoic. In this study, we present a new sequence stratigraphic framework of the Red River Delta based on borehole lithofacies analysis and high resolution seismic data. The Late Pleistocene-Holocene sediments in the coastal zone of the Red River Delta were subdivided into three systems tracts: (1) the lowstand systems tract (LST) is characterized by a Late Pleistocene alluvial silty sand facies complex (arLSTQ1 3b); (2) the transgressive systems tract (TST) is illustrated by the coastal marsh facies complex and the lagoonal greenish-gray clay facies of Early-Middle Holocene (amt, mtTSTQ2 1-2); and (3) the highstand systems tract (HST) is composed of the Middle-Late Holocene deltaic clayish silt facies complex (amhHSTQ2 2-3). The boundaries between these three systems tracts are not isochronous, namely: (1) The LST-HST boundary has been associated with the Würm 2 Glaciation, which occurred at ~40-18 Ka.; (2) The TST-LST boundary is identified by a transgressive erosion surface, whose age ranges from ~12-5 Ka.; and (3) the HST-TST boundary is an unconformity between the submarine deltaic facies complex and the Middle Holocene marine flooding plain.

4.
Radiat Prot Dosimetry ; 190(4): 412-418, 2020 Oct 16.
Article in English | MEDLINE | ID: mdl-32909038

ABSTRACT

Two new contact circumstances called 'stand-lie' and 'front-rear' are implemented to the merged phantom tool. To allow more flexibility for users when they calculate the dose for a volume of interest (VOI) with arbitrary geometry, an optional utility to convert segmented structure information from the CARIMAS software into parallel geometry of GEANT4 is provided. The effective dose for a person who has been in contact with a male patient being treated for thyroid cancer with 131I is calculated for four circumstances: opposite, side by side, stand-lie and front-rear. The biggest dose is the 'opposite' circumstance and the smallest one is the 'stand-lie' circumstance. Using the dose distribution in the patient's body and applying the right circumstance should be done to optimise the dose calculation for the contact person.


Subject(s)
Iodine Radioisotopes , Radiometry , Humans , Male , Monte Carlo Method , Phantoms, Imaging , Software
5.
Phys Med ; 68: 41-46, 2019 Dec.
Article in English | MEDLINE | ID: mdl-31733405

ABSTRACT

PURPOSE: This report introduces a tool for merging two voxel phantoms to calculate the deposited dose that a person receives from a patient undergoing Nuclear medicine procedures. MATERIALS AND METHODS: The phantoms must be converted to the text format used by GEANT4 to treat DICOM images via the GAMOS utilities. The Merge Phantoms Tool can merge two phantoms in two different cases: standing either side by side or opposite. The merged phantom is also in text format and is subsequently input back into GAMOS to calculate the equivalent dose that a person receives from a patient. The equivalent doses to the eyes of people in contact are calculated in a case where a patient was administered 185 MBq of 18F-FDG during a PET examination. RESULTS: The corresponding doses when the two phantoms are standing opposite are greater than those when they are standing side by side and smaller than those from point and tube source calculated by Sumi Yokoyama at any distance. CONCLUSIONS: The Merge phantoms tool and GAMOS software can be used to calculate the deposited dose that a person receives from a patient. An accurate dose calculation can be used for radiation protection, or deciding whether a patient can be released from isolation if the dose is small even in a close contact.


Subject(s)
Monte Carlo Method , Nuclear Medicine , Phantoms, Imaging , Positron Emission Tomography Computed Tomography/instrumentation , Radiation Dosage , Software , Humans
6.
Crit Public Health ; 24(4): 445-460, 2014.
Article in English | MEDLINE | ID: mdl-25378810

ABSTRACT

This paper focuses on the interactions between medical professionals in Hanoi, Vietnam and their HIV-positive patients who desire children. Drawing on ethnographic research, we argue that despite ongoing state and civil society efforts to reduce discrimination against people living with HIV (PLHIV), doctors do stigmatize patients who choose to reproduce, even if the patients are found to have carefully considered all associated risks. While the effects of the Social Evils Campaign linger, the doctors' prejudicial stance towards PLHIV's reproductive desires and risks also reflects the messages communicated by the more recent governmental campaign on Population Quality. The result of this stigmatization is a stratification of reproduction among the Vietnamese citizenry whereby PLHIV are considered obstacles to 'the cleanliness of the race'.

7.
Arch Pharm Res ; 34(3): 455-61, 2011 Mar.
Article in English | MEDLINE | ID: mdl-21547678

ABSTRACT

In order to facilitate the quality control of some selected Korean thistles (Cirsii Herb), Cirsium japonicum var ussuriense, C. japonium var spinosissimum, C. setidens, C. pendulum, C. nipponicum, Carduus crispus, and Breea segetum, a simple, accurate and reliable high performance liguid chromatography method was developed for the simultaneous determination of the six flavonoids: luteolin 5-O-glucoside (1), luteolin 7-O-glucoside (2), hispidulin 7-O-neohesperidoside (3), luteolin (4), pectolinarin (5), and apigenin (6), which were selected as the chemical markers of the thistles. Separation was achieved on an Agilent Eclipse XDB-C18 column with a gradient solvent system of 0.1% trifluoroacetic acid aqueous-methanol at a flow-rate of 1.0 mL/min and detected at 254 nm. All six calibration curves showed good linearity (R(2) > 0.991). The method was reproducible with intra- and inter-day variations of less than 6%. The recoveries were in the range of 90.01-100.05%. This analysis method was successfully utilized to quantify the six flavonoids in the 22 batches of the thistles. The results demonstrated that this method is simple, reliable and suitable for the quality control of this medicinal herb.


Subject(s)
Carduus/chemistry , Cirsium/chemistry , Flavonoids/isolation & purification , Carduus/growth & development , Chromatography, High Pressure Liquid , Cirsium/growth & development , Molecular Structure , Republic of Korea
8.
Bioorg Med Chem Lett ; 20(24): 7435-9, 2010 Dec 15.
Article in English | MEDLINE | ID: mdl-21050759

ABSTRACT

Four new 28-nor-oleanane-type triterpene oligoglycosides, camellenodiol 3-O-ß-D-galactopyranosyl(1→2)[ß-D-xylopyranosyl(1→2)-ß-D-galactopyranosyl(1→3)]-ß-D-glucuronopyranoside (2), camellenodiol 3-O-4''-O-acetyl-ß-D-galactopyranosyl(1→2)[ß-D-xylopyranosyl(1→2)-ß-D-galactopyranosyl(1→3)]-ß-D-glucuronopyranoside (4), camellenodiol 3-O-(ß-D-galactopyranosyl(1→2)[ß-D-xylopyranosyl(1→2)-ß-D-galactopyranosyl(1→3)]-6'-methoxy-ß-D- glucuronopyranoside (5), and maragenin II 3-O-(ß-D-galactopyranosyl(1→2)[ß-D-xylopyranosyl(1→2)-ß-D-galactopyranosyl(1→3)]-6'-methoxy-ß-D-glucuronopyranoside (6), along with two known compounds, (1 and 3), were isolated from the stem bark of Camellia japonica. Their chemical structures were established mainly by 2D NMR techniques and mass spectrometry. The isolated compounds showed inhibitory effects on NO production in RAW264.7 macrophages.


Subject(s)
Camellia/chemistry , Macrophages/metabolism , Nitric Oxide/metabolism , Oleanolic Acid/chemistry , Saponins/chemistry , Lipopolysaccharides/toxicity , Macrophages/immunology , Magnetic Resonance Spectroscopy , Molecular Conformation , Plant Bark/chemistry , Saponins/isolation & purification , Saponins/pharmacology
9.
Chem Pharm Bull (Tokyo) ; 58(1): 121-4, 2010 Jan.
Article in English | MEDLINE | ID: mdl-20045980

ABSTRACT

From the ethyl acetate fraction of the stem bark of Camellia japonica, three new triterpenoids, 3beta-O-acetyl-16beta-hydroxy-12-oxoolean (6), 3beta-O-acetyl-16beta-hydroxy-11-oxoolean-12-ene (7), and 3beta-O-acetyl-16beta-hydroxyolean-12-ene (8), along with seven known compounds, 3alpha-hydroxy-1-oxofriedelan (1), friedelin (2), 3beta-friedelanol (3), canophyllol (4), 3-oxofriedelan-1(2)-ene (5), beta-amyrin (9), camellenodiol (10), and camelledionol (11) were isolated. Their structures were established on the basis of spectroscopic analysis and chemical evidence. The isolated compounds were tested in vitro for their cytotoxic activities against the A549, LLC, HL-60 and MCF-7 cancer cell lines. Among them, compound 8 showed cytotoxicity against LLC and HL-60 cancer cell lines with IC(50) values of 25.2 and 21.7 microM, respectively.


Subject(s)
Antineoplastic Agents, Phytogenic/analysis , Antineoplastic Agents, Phytogenic/pharmacology , Camellia/chemistry , Triterpenes/analysis , Triterpenes/pharmacology , Antineoplastic Agents, Phytogenic/isolation & purification , Cell Line, Tumor , Cell Survival/drug effects , Humans , Molecular Structure , Neoplasms/drug therapy , Plant Bark/chemistry , Triterpenes/isolation & purification
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