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1.
Clin Liver Dis (Hoboken) ; 21(5): 138-142, 2023 May.
Article in English | MEDLINE | ID: mdl-37274950

ABSTRACT

Nucleic acid testing to confirm sustained virological response (SVR) after HCV therapy is technical, often expensive, and frequently unavailable where disease prevalence is highest. Alternative surrogate biomarkers merit evaluation. In a short-treatment trial in Vietnam (SEARCH-1; n = 52) we analysed how changes in alanine transaminase (ΔALT) and aspartate transaminase (ΔAST), from end of treatment (EOT) to EOT + 12 weeks, related to SVR, defined as HCV RNA < lower limit of quantification 12 weeks after EOT. In a separate UK trial (STOPHCV1; n = 202), we then tested the hypothesis that any elevation in ALT or AST between EOT and EOT12 is a sensitive screen for treatment failure. In SEARCH-1, among 48 individuals with data, 13 failed to achieve SVR. Median ΔALT and ΔAST were negative in cured patients but elevated when treatment failed [median ΔALT (IQR): -2 IU/L (-6, +2)] versus +17 IU/L (+7.5, +38) (p< 0.001). Amongst treatment failures, 12/13 had increase in ALT and 13/13 had increase in AST after EOT, compared with 12/35 in those cured. In STOPHCV1, 196/202 patients had evaluable data, of which 57 did not achieve SVR. A rise in ALT after EOT was 100% sensitive (95% C.I. [93.7 - 100%]) and 51% specific (42.4 - 59.7%) for detecting treatment failure. ΔAST >0 IU/L was 98.1% (89.9 - 99.9%) sensitive and 35.8% (27.3 - 45.1%) specific. A rise in ALT or AST after HCV therapy is a highly sensitive screen for treatment failure in mild liver disease. This finding could reduce costs and complexity of managing HCV.

2.
Elife ; 122023 Jan 09.
Article in English | MEDLINE | ID: mdl-36622106

ABSTRACT

Background: World Health Organization has called for research into predictive factors for selecting persons who could be successfully treated with shorter durations of direct-acting antiviral (DAA) therapy for hepatitis C. We evaluated early virological response as a means of shortening treatment and explored host, viral and pharmacokinetic contributors to treatment outcome. Methods: Duration of sofosbuvir and daclatasvir (SOF/DCV) was determined according to day 2 (D2) virologic response for HCV genotype (gt) 1- or 6-infected adults in Vietnam with mild liver disease. Participants received 4- or 8-week treatment according to whether D2 HCV RNA was above or below 500 IU/ml (standard duration is 12 weeks). Primary endpoint was sustained virological response (SVR12). Those failing therapy were retreated with 12 weeks SOF/DCV. Host IFNL4 genotype and viral sequencing was performed at baseline, with repeat viral sequencing if virological rebound was observed. Levels of SOF, its inactive metabolite GS-331007 and DCV were measured on days 0 and 28. Results: Of 52 adults enrolled, 34 received 4 weeks SOF/DCV, 17 got 8 weeks and 1 withdrew. SVR12 was achieved in 21/34 (62%) treated for 4 weeks, and 17/17 (100%) treated for 8 weeks. Overall, 38/51 (75%) were cured with first-line treatment (mean duration 37 days). Despite a high prevalence of putative NS5A-inhibitor resistance-associated substitutions (RASs), all first-line treatment failures cured after retreatment (13/13). We found no evidence treatment failure was associated with host IFNL4 genotype, viral subtype, baseline RAS, SOF or DCV levels. Conclusions: Shortened SOF/DCV therapy, with retreatment if needed, reduces DAA use in patients with mild liver disease, while maintaining high cure rates. D2 virologic response alone does not adequately predict SVR12 with 4-week treatment. Funding: Funded by the Medical Research Council (Grant MR/P025064/1) and The Global Challenges Research 70 Fund (Wellcome Trust Grant 206/296/Z/17/Z).


Hepatitis C is a blood-borne virus that causes thousands of deaths from liver cirrhosis and liver cancer each year. Antiviral therapies can cure most cases of infection in 12 weeks. Unfortunately, treatment is expensive, and sticking with the regimen for 12 weeks can be difficult. It may be especially challenging for unhoused people or those who use injection drugs and who have high rates of hepatitis C infection. Shorter durations of therapy may make it more accessible, especially for high-risk populations. But studies of shorter antiviral treatment durations have yet to produce high enough cure rates. Finding ways to identify patients who would benefit from shorter therapy is a key goal of the World Health Organization. Potential characteristics that may predict a faster treatment response include low virus levels before initiating treatment, patient genetics, drug resistance mutations in the virus, and higher drug levels in the patient's blood during treatment. For example, previous research showed that a rapid decrease in virus levels in a patient's blood two days after starting antiviral therapy with three drugs predicted patient cures after three weeks of treatment. To test if high cure rates could be achieved in just four weeks of treatment, Flower et al. enrolled 52 patients with hepatitis C in a study to receive the most widely accessible dual antiviral treatment (sofosbuvir and daclatasvir). Participants received four or eight weeks of treatment, depending on the amount of viral RNA in their blood after two days of treatment. The results indicate that a rapid decrease in virus levels in the blood does not adequately predict cure rates with four weeks of two-drug combination therapy. However, eight weeks may be highly effective, regardless of viral levels early in treatment. Thirty-four individuals with low virus levels on the second day of treatment received four weeks of therapy, which cured 21 or 62% of them. All seventeen individuals with higher viral levels on day two were cured after eight weeks of treatment. Twelve weeks of retreatment was sufficient to cure the 13 individuals who did not achieve cure with four weeks of therapy. Even patients with drug resistance genes after the first round of therapy responded to a longer second round. Flower et al. show that patient genetics, virus subtype, drug levels in the patient's blood, and viral drug resistance genes before therapy, were not associated with patient cures after four weeks of treatment. Given that retreatment is safe and effective, larger studies are now needed to determine whether eight weeks of therapy with sofosbuvir and daclatasvir may be enough to cure patients with mild liver disease. More studies are also necessary to identify patients that may benefit from shorter therapy durations. Finding ways to shorten antiviral therapy for hepatitis C could help make treatment more accessible and reduce therapy costs for both individuals and governments.


Subject(s)
Hepatitis C, Chronic , Hepatitis C , Adult , Humans , Sofosbuvir/therapeutic use , Antiviral Agents , Pilot Projects , Hepatitis C, Chronic/drug therapy , Drug Therapy, Combination , Treatment Outcome , Hepacivirus/genetics , Genotype , Ribavirin/therapeutic use , Interleukins/genetics
3.
Beilstein J Nanotechnol ; 13: 1108-1119, 2022.
Article in English | MEDLINE | ID: mdl-36262177

ABSTRACT

Zinc oxide nanoparticles (ZnO NPs) were successfully synthesized by a green method using rosin and zinc chloride as salt precursors. The phase structure, morphology, and particle size of ZnO were determined by X-ray powder diffraction, field emission scanning electron microscopy, and high-resolution transmission electron microscopy. The fabricated ZnO NP samples are crystalline with a grain size of 30-100 nm. The ZnO NPs were used as catalysts for the photodegradation of methylene blue (MB) and methyl orange (MO) under visible and UV light. The results indicate that the prepared ZnO material excellently removed MB and MO (c initial = 10 mg/L) with efficiencies of 100% and 82.78%, respectively, after 210 min under UV radiation with a ZnO NP dose of 2 g/L. The photocatalyst activity of the synthesized material was also tested under visible light radiation with the same conditions; however, it achieved lower efficiencies. In addition, ZnO NPs were also tested regarding their antibacterial activity, and the results showed that the prepared ZnO samples had the highest (i.e., 100%) antibacterial efficiency against E. coli.

4.
ScientificWorldJournal ; 2021: 4817900, 2021.
Article in English | MEDLINE | ID: mdl-34887704

ABSTRACT

Alzheimer's disease (AD) is an irreversible neurodegenerative disease that affects many older people adversely. AD has been putting a huge socioeconomic burden on the healthcare systems of many developed countries with aging populations. The need for new therapies that can halt or reverse the progression of the disease is now extremely great. A research approach in the finding new treatment for AD that has attracted much interest from scientists for a long time is the reestablishment of cholinergic transmission through inhibition of acetylcholinesterase (AChE). Naringenin is a flavonoid with the potential inhibitory activity against AChE. From naringenin, many other flavonoid derivatives, such as flavanones and chalcones, can be synthesized. In this study, by applying the Williamson method, nine flavonoid derivatives were synthesized, including four flavanones and five chalcones. The evaluation of AChE inhibitory activity by the Ellman method showed that there were four substances (2, 4, 5, and 7) with relatively good biological activities (IC50 < 100 µM), and these biological activities were better than that of naringenin. The molecular docking revealed that strong interactions with amino acid residue Ser200 of the catalytic triad and those of the peripheral region of the enzyme were crucial for strong effects against AChE. Compound 7 had the strongest AChE inhibitory activity (IC50 13.0 ± 1.9 µM). This substance could be used for further studies.


Subject(s)
Acetylcholinesterase/drug effects , Cholinesterase Inhibitors/pharmacology , Flavanones/chemistry , Flavonoids/pharmacology , Cholinesterase Inhibitors/pharmacokinetics , Cholinesterase Inhibitors/toxicity , Flavonoids/isolation & purification , Flavonoids/pharmacokinetics , Flavonoids/toxicity , Humans , Molecular Docking Simulation , Spectrum Analysis/methods , Structure-Activity Relationship
5.
Open Forum Infect Dis ; 8(7): ofab267, 2021 Jul.
Article in English | MEDLINE | ID: mdl-34337093

ABSTRACT

BACKGROUND: Genotype 6 is the most genetically diverse lineage of hepatitis C virus, and it predominates in Vietnam. It can be treated with sofosbuvir with daclatasvir (SOF/DCV), the least expensive treatment combination globally. In regional guidelines, longer treatment durations of SOF/DCV (24 weeks) are recommended for cirrhotic individuals, compared with other pangenotypic regimens (12 weeks), based on sparse data. Early on-treatment virological response may offer means of reducing length and cost of therapy in patients with liver fibrosis. METHODS: In this prospective trial in Vietnam, genotype 6-infected adults with advanced liver fibrosis or compensated cirrhosis were treated with SOF/DCV. Day 14 viral load was used to guide duration of therapy: participants with viral load <500 IU/mL at day 14 were treated with 12 weeks of SOF/DCV and those ≥500 IU/mL received 24 weeks. Primary endpoint was sustained virological response (SVR). RESULTS: Of 41 individuals with advanced fibrosis or compensated cirrhosis who commenced treatment, 51% had genotype 6a and 34% had 6e. The remainder had 6h, 6k, 6l, or 6o. One hundred percent had viral load <500 IU/mL by day 14, meaning that all received 12 weeks of SOF/DCV. One hundred percent achieved SVR12 despite a high frequency of putative NS5A inhibitor resistance-associated substitutions at baseline. CONCLUSIONS: Prescribing 12 weeks of SOF/DCV results in excellent cure rates in this population. These data support the removal of costly genotyping in countries where genotype 3 prevalence is <5%, in keeping with World Health Organization guidelines. NS5A resistance-associated mutations in isolation do not affect efficacy of SOF/DCV therapy. Wider evaluation of response-guided therapy is warranted.

6.
Molecules ; 26(4)2021 Feb 10.
Article in English | MEDLINE | ID: mdl-33578946

ABSTRACT

Euphorbia tirucalli is a medicine plant possessing many bioactive properties. This paper focused on phytochemical screening (alkaloid, flavonoid, saponin, tannin, and anthraquinone), quantification of polyphenol and flavonoids, and activating evaluation of antioxidants and antimicrobial properties against Xanthomonas axonopodis of different extracts from Euphorbia tirucalli grown in Binh Thuan, Vietnam. The best activity fraction was used for purification and determining bioactive ingredients. The results showed that the phytochemical study revealed the presence of alkaloids, flavonoids, tannins, and terpenoids in the ethyl acetate fraction. Saponin and anthraquinone did not present in all extracts. The content of polyphenol and flavonoid of Euphorbia tirucalli stem was in the range of 16.65-106.32 mg EqAG/g and 97.97-450.83 µg QE/g. The ethyl acetate fraction showed higher amounts of polyphenol and flavonoids and antimicrobial activity against X. axonopodis than other fractions. The antioxidant (SC50) activity of Euphorbia tirucalli stem was in the range of 12.91 ± 0.70 and 528.33 ± 25.15 µg/mL. At concentrations of 5.0 and 7.5 mg/mL, the diameter of inhibition of the ethyl acetate fraction was 14.33 ± 0.76 mm and 17.87 ± 0.57 mm, respectively. The MIC (minimum inhibitory concentration) was 0.156 mg/mL. Scopoletin, gallic acid, and piperic acid got MICs corresponding to 78, 312, and 312 µg/mL, respectively. Scopoletin, gallic acid, and piperic acid were found in the ethyl acetate fraction of Euphorbia tirucalli and exhibited the treatment of citrus bacteria canker and plant diseases.


Subject(s)
Anti-Bacterial Agents/pharmacology , Antioxidants/pharmacology , Euphorbia/chemistry , Phytochemicals/isolation & purification , Phytochemicals/pharmacology , Plant Extracts/pharmacology , Xanthomonas axonopodis/drug effects , Vietnam
7.
Polymers (Basel) ; 12(5)2020 May 16.
Article in English | MEDLINE | ID: mdl-32429371

ABSTRACT

A series of semi-interpenetrating polymer network (semi-IPN) hydrogels based on N,N'-diethylacrylamide (DEA) and itaconamic acid (IAM) were synthesized by changing the molar ratio of linear copolymer P(DEA-co-IAM) and DEA monomer. Linear copolymer P(DEA-co-IAM) was introduced into a solution of DEA monomer to prepare pH-thermo dual responsive P(DEA-co-IAM)/PDEA semi-IPN hydrogels. The thermal gravimetric analysis (TGA) revealed that the semi-IPN hydrogel has a higher thermal stability than the conventional hydrogel, while the interior morphology by scanning electron microscopy (SEM) showed a porous structure with the pore sizes could be controlled by changing the ratio of linear copolymer in the obtained hydrogels. The oscillatory parallel-plate rheological measurements and compression tests demonstrated a viscoelastic behavior and superior mechanical properties of the semi-IPN hydrogels. Besides, the lower critical solution temperature (LCST) of the linear copolymers increased with the increase of IAM content in the feed, while the semi-IPN hydrogels increased LCSTs with the increase of linear copolymer content introduced. The pH-thermo dual responsive of the hydrogels was investigated using the swelling behavior in various pH and temperature conditions. Finally, the swelling and deswelling rate of the hydrogels were also studied. The results indicated that the pH-thermo dual responsive semi-IPN hydrogels were synthesized successfully and may be a potential material for biomedical, drug delivery or absorption applications. The further applications of semi-IPN hydrogels are being conducted.

8.
Odontology ; 107(1): 17-22, 2019 Jan.
Article in English | MEDLINE | ID: mdl-29752597

ABSTRACT

Developmental defects of enamel (DDE) are induced and regulated by several factors including genetics and the environment. There is evidence showing that dioxin in polluted areas has a strong effect on the health and development of teeth. However, there has been no study on DDE in the dioxin-affected regions in Vietnam. To identify the effect of dioxin on the prevalence of DDE in studied areas in Vietnam, a cross-sectional study was conducted in 2200 adults in the A Luoi district in the Thua Thien Hue province (the dioxin-affected region) and in the Kim Bang district in the Ha Nam province (dioxin-unaffected region) in 2015. All subjects were interviewed using a structured questionnaire and their teeth were examined and scored for enamel defects based on the 1992 FDI criteria. The defected teeth were then photographed. Our results showed that the DDE rate in A Luoi was 20.5% when measured as mouth prevalence and 5.8% when measured as tooth prevalence, while the rates in Kim Bang were 10.4 and 2.32% for mouth and tooth prevalence, respectively. Demarcated opacities were predominated in both districts (45.5% in A Luoi and 52.2% in Kim Bang). The DDE rate of the anterior teeth group was higher than that of the posterior teeth group. Most lesions presented on the buccal surface of the tooth. Overall, the DDE prevalence in the dioxin-affected region was 2.2 times higher than that in non-dioxin-affected region in the studied regions in Vietnam.


Subject(s)
Dental Enamel Hypoplasia/chemically induced , Dental Enamel Hypoplasia/epidemiology , Dioxins/toxicity , Environmental Exposure/adverse effects , Adolescent , Adult , Cross-Sectional Studies , Female , Humans , Male , Middle Aged , Prevalence , Surveys and Questionnaires , Vietnam/epidemiology
9.
Acta Biomater ; 74: 397-413, 2018 07 01.
Article in English | MEDLINE | ID: mdl-29775731

ABSTRACT

This study demonstrated the targeted delivery and controlled release of cisplatin drug molecules from doubly decorated mesoporous silica nanoparticles (MSNs), which were internally grafted with fluorescent conjugates and externally coated with polydopamine (PDA) and graphene oxide (GO) layers. The brush-like internal conjugates conferred fluorescent functionality and high capacity of cisplatin loading into MSNs, as well as contributing to a sustained release of the cisplatin through a porous channel with the assistance of external PDA layer. A consolidated double-layer formed by electrostatic interactions between the GO nanosheet and the PDA layer induced more controlled release kinetics which was well predicted by Higuchi model. In addition, Our MSNs exhibited stimuli (pH, NIR irradiation)-responsive controlled release as a potential chemo-photothermal agent against cancer cells. In a cell test, multifunctional MSNs showed a low toxicity itself, but gave a high cytotoxicity against human epithelial neuroblastoma cells (SH-SY5Y) after loading cisplatin. Notably, GO-wrapped MSNs exhibited very effective drug delivery because GO wrapping enhanced their dispensability in aqueous solution, photothermal heating effect, and efficient endocytosis into cells. Furthermore, monoclonal antibody (anti-human epidermal growth factor receptor)-conjugated MSNs showed a higher specificity, which resulted in more enhanced anticancer effects in vitro. The current study demonstrated a reliable synthesis of multifunctional MSNs, endowed with fluorescent imaging, stimuli-responsive controlled release, higher specificity, and efficient cytotoxicity toward cancer cells. STATEMENT OF SIGNIFICANCE: The current study demonstrated the reliable synthesis of multifunctional mesoporous silica nanoparticles (MSNs) with internal fluorescent conjugates and external polydopamine and graphene oxide (GO) layers. The combination of internal conjugates and external coating layers produced an effective pore closure effect, leading to controlled and sustained release of small drug molecules. Notably, GO wrapping improved the dispensability and cellular uptake of the MSNs, as well as enhanced drug-controlled release. Our multifunctional MSNs revealed very efficient drug delivery effects against human epithelial neuroblastoma cells by demonstrating several strengths: i) fluorescent imaging, ii) sustained and controlled release of small drug molecules, iii) efficient cellular uptake, cytotoxicity and specificity, and v) stimuli (pH, NIR irradiation)-responsive controlled release as a potential chemo-photothermal agent.


Subject(s)
Cisplatin , Coated Materials, Biocompatible , Graphite , Hyperthermia, Induced , Indoles , Nanoparticles , Neuroblastoma , Phototherapy , Polymers , Silicon Dioxide , Cell Line, Tumor , Cisplatin/chemistry , Cisplatin/pharmacokinetics , Cisplatin/pharmacology , Coated Materials, Biocompatible/chemistry , Coated Materials, Biocompatible/pharmacokinetics , Coated Materials, Biocompatible/pharmacology , Delayed-Action Preparations/chemistry , Delayed-Action Preparations/pharmacokinetics , Delayed-Action Preparations/pharmacology , Graphite/chemistry , Graphite/pharmacokinetics , Graphite/pharmacology , Humans , Indoles/chemistry , Indoles/pharmacokinetics , Indoles/pharmacology , Nanoparticles/chemistry , Nanoparticles/therapeutic use , Neuroblastoma/metabolism , Neuroblastoma/pathology , Neuroblastoma/therapy , Polymers/chemistry , Polymers/pharmacokinetics , Polymers/pharmacology , Porosity , Silicon Dioxide/chemistry , Silicon Dioxide/pharmacokinetics , Silicon Dioxide/pharmacology
10.
J Agric Food Chem ; 60(7): 1737-41, 2012 Feb 22.
Article in English | MEDLINE | ID: mdl-22296105

ABSTRACT

Degraded alginate compounds with molecular weights of 7-26, 40-77, or 11-26 kDa were obtained by γ irradiation, hydrogen peroxide (5% H(2)O(2)) treatment, or a combination treatment involving ionizing radiation and H(2)O(2), respectively. The 14 kDa oligoalginate, prepared by the combined method, promoted the growth of mustard greens and lettuce at an optimal concentration of 75 mg/L. The growth promotion effects of the oligoalginate prepared by γ irradiation in the presence of H(2)O(2) were statistically equivalent to those of the oligoalginate prepared by γ irradiation only. The combination of γ irradiation and H(2)O(2) reduced the required irradiation dosage by a factor of 9 relative to the oligoalginate produced by γ irradiation only. The combination treatment (γ irradiation/H(2)O(2)) may be carried out on a large scale at low cost to produce oligoalginate for use as a plant growth promoter in agricultural industries.


Subject(s)
Alginates/chemistry , Gamma Rays , Hydrogen Peroxide/chemistry , Plant Growth Regulators/chemical synthesis , Alginates/pharmacology , Alginates/radiation effects , Glucuronic Acid/chemistry , Glucuronic Acid/pharmacology , Glucuronic Acid/radiation effects , Hexuronic Acids/chemistry , Hexuronic Acids/pharmacology , Hexuronic Acids/radiation effects , Lactuca/drug effects , Lactuca/growth & development , Molecular Weight , Mustard Plant/drug effects , Mustard Plant/growth & development , Plant Growth Regulators/pharmacology , Solutions , Spectroscopy, Fourier Transform Infrared
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