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Assessment of hemostatic ability of biomaterial based on chitosan and Eclipta prostrataL. extract. Biomed Mater 2024; 19:035026. [PMID: 38537280 DOI: 10.1088/1748-605x/ad386e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2023] [Accepted: 03/26/2024] [Indexed: 04/05/2024]
Abstract
The biomaterials based on chitosan andEclipta prostrataL. extract have been prepared by microemulsion method and solution method (with and without sodium tripolyphosphate (STPP) as a cross-linking agent). The main component inEclipta prostrataL. extract is flavonoid groups. The structure of the chitosan/extract biomaterials was studied by infrared spectroscopy. The chitosan/extract biomaterial using STPP cross-linker appeared an absorption band at 1152 cm-1attributed to the vibrations of C-O-P bonds, which proved that chitosan has crosslinked with STPP. The morphology of the biomaterials was investigated by the dynamic light scattering technique and field emission scanning electron microscopy. The obtained results showed that the particle size of the chitosan/extract biomaterials prepared by microemulsion method and solution method with STPP ranged from 68.06 nm to 1484 nm, with an average particle size of 304.9-1019 nm. The microemulsion method produced biomaterials with much smaller average particle size than the solution method using cross-linkers. The hemostatic ability of the biomaterials was better than that of the control sample based on the time of blood clotting formation and glomerular aggregation ability. The sample with the ratio ofE. prostrataL. extract: chitosan of 1:30 had the lowest hemostasis time (6 min 46 s) and its glomerular aggregation rate after 5 min was 13.05%. This indicated that the biomaterials based on chitosan andE. prostrataL. extract are promising for application in biomedicine as hemostatic materials.
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Camellia annamensis (Theaceae): phytochemical analysis, cytotoxic, antioxidative, and antimicrobial activities. Nat Prod Res 2024:1-7. [PMID: 38225908 DOI: 10.1080/14786419.2024.2302900] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2023] [Accepted: 01/02/2024] [Indexed: 01/17/2024]
Abstract
Cytotoxic, antioxidative, and antimicrobial activities of Camellia annamensis, and its chemical compositions were first provided in the current study. Phenolic contents in the methanol extracts of its leaves and flowers were 222.73 ± 0.09 and 64.44 ± 0.08 mg GAE/g extract, whereas flavonoid contents in these parts were 108.80 ± 0.28 and 131.26 ± 0.39 mg rutin/g extract, respectively. By using HPLC-DAD analysis, gallic acid (43.72 ± 0.09 - 81.89 ± 1.83 mg/g) and (-)-epigallocatechin gallate (67.31 ± 1.26 - 70.68 ± 7.82 mg/g) were identified as the major compounds. C. annamensis leaf and flower extracts were moderately cytotoxic against A549, HT-29, SK-Mel-2, MCF-7, HepG2, HeLa, and MKN-7. Particularly, they are better than the standards trolox (IC50 7.57 ± 0.23 µg/mL) in lipid peroxidation inhibitory evaluation, and streptomycin (IC50/MIC = 45.34-50.34/128-256 µg/mL) in antimicrobial assay against the Gram-positive bacteria Enterococcus faecalis ATCC299212, Staphylococcus aureus ATCC25923, and the Gram-negative bacterium Salmonella enterica ATCC13076.
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Essential Oils of Five Syzygium Species Growing Wild in Vietnam: Chemical Compositions and Antimicrobial and Mosquito Larvicidal Potentials. Molecules 2023; 28:7505. [PMID: 38005226 PMCID: PMC10672915 DOI: 10.3390/molecules28227505] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2023] [Revised: 10/29/2023] [Accepted: 11/01/2023] [Indexed: 11/26/2023] Open
Abstract
The essential oils of five Vietnamese Syzygium species (Syzygium levinei, S. acuminatissimum, S. vestitum, S. cumini, and S. buxifolium) were first hydro-distilled and analyzed using GC-FID/MS (gas chromatography-flame ionization detection/mass spectrometry). Monoterpene hydrocarbons, sesquiterpene hydrocarbons, and oxygenated sesquiterpenoids were the main chemical classes in these oils. All these essential oils showed good-excellent antimicrobial activities against Gram-positive bacteria Enterococcus faecalis, Staphylococcus aureus, and Bacillus cereus, and the yeast Candida albicans. S. levinei leaf essential oil, rich in bicyclogermacrene (25.3%), (E)-β-elemene (12.2%), (E)-caryophyllene (8.2%), and β-selinene (7.4%), as well as S. acuminatissimum fruit essential oil containing (E)-caryophyllene (14.2%), α-pinene (12.1%), caryophyllene oxide (10.9%), β-selinene (10.8%), α-selinene (8.0%), and α-humulene (5.7%), established the same MIC value of 8 µg/mL against E. faecalis and B. cereus, which were much better than the positive control streptomycin (MIC 128-256 µg/mL). The studied essential oils showed the potential to defend against mosquitoes since they caused the 24 and 48 h LC50 values of less than 50 µg/mL against the growth of Culex quinquefasciatus and Aedes aegypti larvae. Especially, S. buxifolium leaf essential oil strongly inhibited Ae. aegypti larvae with 24 and 48 h LC50 values of 6.73 and 6.73 µg/mL, respectively, and 24 and 48 h LC90 values of 13.37 and 10.83 µg/mL, respectively. These findings imply that Vietnamese Syzygium essential oils might have potential for use as supplemental antibacterial agents or as "green" alternatives for the control of mosquitoes.
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New Dibenzocyclooctadiene Lignans and Phenolics from Kadsura heteroclite with Anti-Inflammatory Activity. Chem Biodivers 2023; 20:e202300904. [PMID: 37550247 DOI: 10.1002/cbdv.202300904] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2023] [Revised: 08/03/2023] [Accepted: 08/07/2023] [Indexed: 08/09/2023]
Abstract
A chemical investigation of K. heteroclite led to isolation of two new dibenzocyclooctadienes (1 and 2) together with 14 known compounds (3-16) by using multiple chromatographic techniques. New compounds (1 and 2) were obtained and identified by spectroscopic methods (HR-ESI-MS, 1D and 2D NMR, and ECD) as well as by comparison of their experimental data with those reported in the literatures. All the isolates were evaluated for their ability to modulate TNF-α production in lipopolysaccharide (LPS) stimulated RAW264.7 cells. Among them, compound 5 displayed the most inhibition against tumor necrosis factor (TNF)-α production with IC50 value of 6.16±0.14 μM. Whereas, compounds (1, 3, and 6) showed the significant inhibition (IC50 values ranging from 9.41 to 14.54 μM), and compounds (2, 4, 9, 10, 13, 15, and 16) exhibited moderate inhibition (IC50 values ranging from 19.27 to 40.64 μM) toward TNF-α production, respectively.
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Synthesis and characterization of some novel polythiophene derivatives containing pyrazoline. Des Monomers Polym 2022; 25:136-147. [PMID: 35693727 PMCID: PMC9186369 DOI: 10.1080/15685551.2022.2086413] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Eight polythiophene derivatives containing pyrazoline side groups were synthesized by a chemical oxidative coupling polymerization using FeCl3. The crystal structures of four monomers were determined which confirm the almost perpendicular orientation of the thiophene and pyrazoline rings, while the other substituents are more coplanar. Analyses of IR, 1H-NMR, Raman and UV-Vis spectra demonstrated that the suggested polymerization was successful to generate the synthesized polythiophenes with the expected structures. The morphology of the synthesized polythiophenes was studied by SEM. The different substituents attached to the 1- and 3-positions of the pyrazoline side chain led to differences in optical properties, electrical conductivity, and thermal stability of the synthesized polythiophenes. By adding a pyrazoline side chain to polythiophenes, some polymers achieve good solubility, electrical conductivity of about 1.3 × 10–6 S/cm, high fluorescence intensity (above 40,000 a.u.) at 505–550 nm and thermal stability up to 590°C in the air.
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An assessment of current tuberculosis patient care and support policies in high-burden countries. Int J Tuberc Lung Dis 2021; 24:36-42. [PMID: 32005305 DOI: 10.5588/ijtld.19.0183] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
CONTEXT: Adherence to treatment for tuberculosis (TB) is an important predictor of treatment outcomes. The World Health Organization guidelines recommend a patient-centred approach to adherence support; however, the extent to which policies in high-burden countries facilitate this approach remains uncertain.DESIGN: A cross-sectional survey of current national patient care and support policies in high TB burden countries was performed.RESULT: Responses were provided by TB care programmes in 23 of the 30 high TB burden countries, comprising 77.4% of TB cases globally. Clinic-based and household adherence support and patient education were recommended in all countries, while policies for digital technologies and social supports have been adopted in a small minority of countries. Financial or material support (such as reimbursement for transportation) and psychological support to patients-if included in the policies-was mainly recommended only for specific sub-groups of patients.CONCLUSION: National policies in many countries have not yet fully adopted global recommendations for patient care and support. Further scale-up of evidence-based approaches to care is required to improve quality of care for patients in high TB burden settings.
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Potential benefits of active case finding to reduce the burden of TB. Int J Tuberc Lung Dis 2021; 25:93-94. [PMID: 33656419 DOI: 10.5588/ijtld.20.0894] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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Correction to Perfluorinated Self-Assembled Monolayers Enhance the Stability and Efficiency of Inverted Perovskite Solar Cells. ACS NANO 2020; 14:16156. [PMID: 33166445 DOI: 10.1021/acsnano.0c08081] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
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Is effective patient support missing in the global response to multidrug-resistant tuberculosis? Int J Tuberc Lung Dis 2020; 24:626-630. [PMID: 32553006 DOI: 10.5588/ijtld.19.0529] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Multidrug-resistant tuberculosis (MDR-TB) is a threat to the achievement of the global targets to the World Health Organization (WHO) End TB by 2030 Strategy. The WHO consolidated guidelines for the treatment of drug-resistant TB emphasise the importance of addressing health systems issues, including supporting patients during treatment, contributing to improved adherence, reduced catastrophic costs and better treatment outcomes. The recently published results of the STREAM (Standardised Treatment Regimen of Anti-TB Drugs for Patients with MDR-TB) clinical trial and the Delamanid 213 Trial suggest that the implementation of a proper patient-centred approach to the clinical and programmatic management of MDR-TB as per the WHO guidelines is key to improving treatment outcomes in MDR-TB patients.
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Synthesis of polythiophene containing heterocycle on the side chain: A review. VIETNAM JOURNAL OF CHEMISTRY 2020. [DOI: 10.1002/vjch.201900184] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
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Perfluorinated Self-Assembled Monolayers Enhance the Stability and Efficiency of Inverted Perovskite Solar Cells. ACS NANO 2020; 14:1445-1456. [PMID: 31909973 DOI: 10.1021/acsnano.9b03268] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Perovskite solar cells are among the most exciting photovoltaic systems as they combine low recombination losses, ease of fabrication, and high spectral tunability. The Achilles heel of this technology is the device stability due to the ionic nature of the perovskite crystal, rendering it highly hygroscopic, and the extensive diffusion of ions especially at increased temperatures. Herein, we demonstrate the application of a simple solution-processed perfluorinated self-assembled monolayer (p-SAM) that not only enhances the solar cell efficiency, but also improves the stability of the perovskite absorber and, in turn, the solar cell under increased temperature or humid conditions. The p-i-n-type perovskite devices employing these SAMs exhibited power conversion efficiencies surpassing 21%. Notably, the best performing devices are stable under standardized maximum power point operation at 85 °C in inert atmosphere (ISOS-L-2) for more than 250 h and exhibit superior humidity resilience, maintaining ∼95% device performance even if stored in humid air in ambient conditions over months (∼3000 h, ISOS-D-1). Our work, therefore, demonstrates a strategy towards efficient and stable perovskite solar cells with easily deposited functional interlayers.
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Synthesis and characterization of novel poly[4-phenyl-3-(thiophen-3-ylmethyl)-1 H
-1,2,4-triazole-5(4 H
)-thione]. VIETNAM JOURNAL OF CHEMISTRY 2020. [DOI: 10.1002/vjch.2019000141] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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No universal access to drug-resistant tuberculosis care without engaging all health care providers. Int J Tuberc Lung Dis 2020; 24:118-123. [PMID: 32005315 DOI: 10.5588/ijtld.19.0436] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Should the engagement of all health care providers in all aspects of programmatic management of drug-resistant tuberculosis (PMDT) become a priority in the national strategic plans for tuberculosis (TB), progress towards universal access to diagnosis, treatment and care of drug-resistant tuberculosis (DR-TB) would accelerate. This would be especially crucial in countries where the private sector is a significant provider of health services. Proven successful interventions to engage all health care providers and partners in the cascade of prevention, diagnosis, treatment and care of DR-TB patients need to be urgently scaled up. Such engagement should not be limited to the diagnosis and treatment of DR-TB, but extended also to all the aspects of PMDT, including approaches ensuring that patient-centred care, social support, pharmacovigilance and surveillance. Integral to the End TB Strategy, PMDT should be embedded in all public-private mix initiatives for TB and vice versa.
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Building operational research capacity in the Pacific. Public Health Action 2015; 4:S2-S13. [PMID: 26477282 DOI: 10.5588/pha.13.0091] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2013] [Accepted: 01/27/2014] [Indexed: 11/10/2022] Open
Abstract
Operational research (OR) in public health aims to investigate strategies, interventions, tools or knowledge that can enhance the quality, coverage, effectiveness or performance of health systems. Attention has recently been drawn to the lack of OR capacity in public health programmes throughout the Pacific Islands, despite considerable investment in implementation. This lack of ongoing and critical reflection may prevent health programme staff from understanding why programme objectives are not being fully achieved, and hinder long-term gains in public health. The International Union Against Tuberculosis and Lung Disease (The Union) has been collaborating with Pacific agencies to conduct OR courses based on the training model developed by The Union and Médecins Sans Frontières Brussels-Luxembourg in 2009. The first of these commenced in 2011 in collaboration with the Fiji National University, the Fiji Ministry of Health, the World Health Organization and other partners. The Union and the Secretariat of the Pacific Community organised a second course for participants from other Pacific Island countries and territories in 2012, and an additional course for Fijian participants commenced in 2013. Twelve participants enrolled in each of the three courses. Of the two courses completed by end 2013, 18 of 24 participants completed their OR and submitted papers by the course deadline, and 17 papers have been published to date. This article describes the context, process and outputs of the Pacific courses, as well as innovations, adaptations and challenges.
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The trend of tuberculosis cases over 60 years in Fiji's largest treatment centre: 1950-2010. Public Health Action 2015; 4:42-6. [PMID: 26423760 DOI: 10.5588/pha.13.0100] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2013] [Accepted: 02/21/2014] [Indexed: 11/10/2022] Open
Abstract
SETTING P J Twomey Hospital, National Tuberculosis Programme, Fiji. OBJECTIVES To review the trend in numbers of tuberculosis (TB) cases registered each year from 1950 to 2010 at P J Twomey Hospital, Fiji's largest TB treatment centre and central TB unit, and to consider trends in the context of key TB control events in Fiji. DESIGN Descriptive study of data from medical records and TB registers, including age, sex, ethnicity, TB diagnosis and smear result. RESULTS Between 1950 and 2010, 14 616 cases were registered at P J Twomey Hospital. Of these, 58% were male, 70% were indigenous Fijians (i-taukei) and 64% were aged 15-49 years. The caseload dropped sharply in the 1960s, and has fallen steadily since 1990. Smear results were available for the majority of cases (91%). Between 1950 and 1985, smear-positive cases accounted for 19% of cases overall; this increased to 41% after 1985 following laboratory training. The numbers of sputum smear-positive cases recorded each year has been increasing in the last decade. CONCLUSION There have been marked changes in TB caseload over the last 60 years at Fiji's largest TB treatment centre. The recent increase in smear-positive cases while total TB cases have been falling needs further evaluation.
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Nurses graduating in Fiji between 2001 and 2010: sufficient supply for Fiji's health service demands? Public Health Action 2013; 3:63-7. [PMID: 26392998 DOI: 10.5588/pha.12.0067] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2012] [Accepted: 01/10/2013] [Indexed: 11/10/2022] Open
Abstract
SETTING Fiji's schools of nursing and government health services, 2001-2010. OBJECTIVES To report on 1) the number and characteristics of nurses who graduated in Fiji, 2) the proportion of vacant nursing positions in the government health services and 3) attrition among nurses. DESIGN Descriptive study involving a retrospective record review of Ministry of Health annual reports and nursing registers. RESULTS Over the period 2001-2010, a total of 1500 nurses graduated, with the overall trend being a gradual increase in newly qualified nurses year on year. Available data from 2007 onwards showed relatively low vacancy rates (range 0.4-2%), with a sharp rise to 15% in 2009. Complete data on nurse attrition were available only from 2007 onwards, with rates of attrition ranging from 4% to 10%; the most common reason for attrition was resignation. CONCLUSION While it was unable to directly assess whether Fiji's supply of nursing graduates has been meeting the country's health service demands, this study provides a series of baseline data on Fiji's nurse graduate and nursing workforce. In addition, it identifies some of the challenges and gaps that need to be considered to better assess and address nursing staff shortages.
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Sputum smear examination and time to diagnosis in patients with smear-negative pulmonary tuberculosis in the Pacific. Public Health Action 2012; 2:133-7. [PMID: 26392971 DOI: 10.5588/pha.12.0030] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2012] [Accepted: 08/24/2012] [Indexed: 11/10/2022] Open
Abstract
SETTING National tuberculosis programmes (NTPs) in Kiribati and the Marshall Islands, 2006-2010. OBJECTIVE To determine the proportion of all tuberculosis (TB) cases that were pulmonary smear-negative, and for these patients to determine how many sputum smears were examined and the time from sputum smear examination to registration. DESIGN A retrospective cross-sectional study involving a record review of national TB and laboratory registers. RESULTS Of 2420 TB cases identified, 709 (29%) were registered as smear-negative pulmonary TB. Of the 695 (98%) with information on smear examination, 222 (32%) had no smear recorded, 61 (9%) had one smear, 86 (12%) two smears and 326 (47%) three smears. Among the 473 patients who had at least one smear, 238 (50%) were registered before sputum examination, 131 (28%) within 1 week, 72 (15%) between 1 and 4 weeks, and 34 (7%) >4 weeks after sputum examination. CONCLUSION NTPs in Kiribati and the Marshall Islands are diagnosing 29% of all TB patients as smear-negative pulmonary TB. Many patients do not have smears done or are registered before undergoing smear examination. Corrective measures are needed.
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Drimane-type sesquiterpenes with a dioxabicyclooctane skeleton from the fruiting bodies of Nigrofomes melanoporus and their cytotoxicity. PLANTA MEDICA 2012; 78:737-739. [PMID: 22437245 DOI: 10.1055/s-0031-1298367] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Two new drimane-type compounds, nigrofomins A ( 1) and B ( 2), possessing a rare dioxabicyclooctane moiety, were purified from the fruiting bodies of Nigrofomes melanoporus. Their structures were determined using 1D-, 2D-NMR and HR-ESI-MS spectroscopic analyses. In addition, 1 was established by X-ray crystallographic studies. Both nigrofomins A ( 1) and B ( 2) exhibited cytotoxicity on acute T-cell leukemia (Jurkat), human nasopharyngeal carcinoma (NPC-TW01), and lung cancer (NCI-H661) cells with IC (50) values in the range of 99.44-246.32 µM. Furthermore, the effects of 1 and 2 on cell-cycle progression of Jurkat cells displayed a concentration-dependent accumulation in the G (0)/G (1) phase.
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Surface structure and structural point defects of liquid and amorphous aluminosilicate nanoparticles. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2008; 20:265005. [PMID: 21694354 DOI: 10.1088/0953-8984/20/26/265005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
The surface structure of liquid and amorphous aluminosilicate nanoparticles of composition Al(2)O(3)·2SiO(2) has been investigated in a model of different sizes ranging from 2.0 to 5.0 nm with the Born-Mayer type pair potential under non-periodic boundary conditions. Models have been obtained by cooling from the melts at a constant density of 2.6 g cm(-3) via molecular dynamics (MD) simulation. The surface structure has been investigated via the coordination number, bond-angle distributions and structural point defects. Calculations show that surface effects on surface static and thermodynamic properties of models are significant according to the change in the number of Al atoms in the surface layers. Evolution of the local environment of oxygen in the surface shell of nanoparticles upon cooling from the melt toward the glassy state was also found and discussed. In addition, the nanosize dependence of the glass transition temperature was presented.
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Radiographic predictors of subsequent reactivation of tuberculosis. Int J Tuberc Lung Dis 2007; 11:1136-1142. [PMID: 17945072] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/25/2023] Open
Abstract
SETTING A cohort of migrants to Australia (n = 7265) selected to be at increased risk of tuberculosis (TB) were assessed at the Liverpool Chest Clinic, Sydney, between 1984 and 2003. OBJECTIVE To assess the reproducibility and predictive value of various radiographic criteria for predicting the subsequent development of TB. METHODS A nested case control study was conducted. Cases were those who had a confirmed diagnosis of TB during follow-up (n = 60). A random sample of 107 controls was selected. Initial chest X-rays were read independently and blinded to case vs. control status by two readers according to two classification systems. Agreement was quantified as weighted kappa (kappaw). Sensitivity and specificity for subsequent TB were estimated. RESULTS There was moderate agreement between readers for both classification systems (kappaw 0.67 and 0.60, respectively). The presence of calcified nodular densities or fibrosis together with non-calcified nodular densities in mid and/or upper lung zones or the presence of a pulmonary infiltrate typical of TB had a sensitivity of 66% for subsequent pulmonary TB and a specificity of 82%. Minor abnormalities or findings consistent with past primary TB infection alone were not predictive of subsequent TB. CONCLUSIONS Radiographic screening can be helpful in identifying individuals at increased risk of subsequent TB.
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Evaluation of sputum smear microscopy in the National Tuberculosis Control Programme in the north of Vietnam. Int J Tuberc Lung Dis 2006; 10:277-82. [PMID: 16562707] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/08/2023] Open
Abstract
OBJECTIVE To assess the yield of sputum smear microscopy and sex differences in the National Tuberculosis Control Programme in the north of Vietnam. METHODS Review of registers of 30 randomly selected laboratories (26 district, 4 provincial level). RESULTS The average daily workload per technician was 4.4 examinations in district and 5.3 examinations in provincial laboratories. To find one smear-positive case, 9.7 suspects were examined and 29.3 smears done. The smear-positive rate (mean 10.3%) was higher among men (11.6%) than among women (8.4%, P < 0.001). There were more men than women among tuberculosis (TB) suspects (male:female ratio 1.36, 95%CI 1.19-1.54), but even more so among smear-positive patients (1.89, 95%CI 1.64-2.14), irrespective of specimen quality and number of smears examined. Three smears were examined for 18,055 suspects (61.7%). The incremental gain was 33.5% and 4.9% for the second and third smear examination, respectively; 186 (95%CI 160-221) smears needed to be examined to find one additional case of TB with a third serial examination. CONCLUSION The diagnostic process seemed generally efficient. The male:female ratios suggest higher TB incidence in men rather than lower access to TB facilities for women. The third smear examination could be omitted.
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Typhoid fever. Studies of blood coagulation, bacteremia, and endotoxemia. ARCHIVES OF INTERNAL MEDICINE 1978; 138:407-10. [PMID: 629635 DOI: 10.1001/archinte.138.3.407] [Citation(s) in RCA: 28] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Patients with typhoid fever were studied to determine whether disseminated intravascular coagulation (DIC), circulating bacteria, and endotoxemia were responsible for the signs and symptoms of their illnesses. Coagulation tests in 28 patients detected thrombocytopenia in 17, hypofibrinogenemia in nine, and elevated titers of fibrinogen-related antigens in 20. Repeated testing during convalescence showed a return toward normal values. Intestinal bleeding, however, did not correlate with abnormalities of coagulation tests. Thus, DIC occurred commonly but appeared to be a subclinical event in these patients. In 25 patients with positive blood cultures for Salmonella typhi, quantitative cultures detected from less than 10 to 9 x 10(2) bacteria/ml. Limulus tests for endotoxin in plasma were negative in all 21 patients tested. These results indicated that the concentrations of circulating bacteria and endotoxin in typhoid fever are lower than in other Gram-negative bacterial infections and suggested that circulating bacteria and endotoxin do not play a major role in the pathogenesis of typhoid fever.
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Abstract
Antimicrobial-resistant typhoid fever in Saigon was studied by examining in vitro antimicrobial susceptibilities of Salmonella typhi strains and conducting a randomized clinical trial of ampicillin and trimethoprim-sulfamethoxazole (TMP-SMZ). Isolates of S. typhi were obtained from blood or stool cultures of 90 patients. Of 87 isolates tested for antimicrobial susceptibility, 65 (75%) were resistant (R) to chloramphenicol, streptomycin, sulfonamide, and tetracycline, and 22 (25%) were susceptible (S). The drug resistance was transferable to Escherichia coli and was found in 11 different Vi-phage types. All isolates were susceptible to ampicillin and to TMP-SMZ. Agar dilution studies of TMP and SMZ showed synergistic inhibition of growth in all 18 S isolates and in 12 of 48 R isolates tested. The clinical trial of ampicillin and TMP-SMZ showed that both drugs were equally effective. Treatment failure with both drugs was more frequent in patients with S isolates than in patients with R isolates. Therefore, in an area where antimicrobial-resistant typhoid fever exists, patients with R isolates should receive either ampicillin or TMP-SMZ, but patients with S isolates should be treated with chloramphenicol.
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Yersinia pestis infection in Vietnam. II. Quantiative blood cultures and detection of endotoxin in the cerebrospinal fluid of patients with meningitis. J Infect Dis 1976; 133:493-9. [PMID: 1262715 DOI: 10.1093/infdis/133.5.493] [Citation(s) in RCA: 64] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Quantitative blood cultures were obtained from 42 patients with acute Yersinia pestis infection to determine whether the concentration of bacteria in blood influenced the clinical severity and outcome of illness. In 17 bacteremic patients, colony counts in blood cultures ranged from less than 10 to 4 X 10(7)/ml. Three of five patients with colony counts of greater than 10(2)/ml died, and two patients survived episodes of hypotension. Results from plasma limulus tests were positive at the time of admission in three of 10 patients tested, and these three patients had bacteremia with colony counts of greater than 10(2)/ml. Meningitis developed in three patients and pneumonia in two patients; these five patients a-l had buboes in the axillary region. Endotoxin was detected with the limulus test in the cerebrospinal fluid in the three patients with meningitis. Ten patients randomly assigned to receive streptomycin or trimethoprim-sulfamethoxazole survived. Those treated with streptomycin had a shorter median duration of fever and a lower incidence of complications than did the patients treated with trimethoprim-sulfamethoxazole.
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Oxolinic acid in the treatment of typhoid fever due to chloramphenicol-resistant strains of Salmonella typhi. Antimicrob Agents Chemother 1976; 9:387-92. [PMID: 1259398 PMCID: PMC429541 DOI: 10.1128/aac.9.3.387] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Of 28 strains of Salmonella typhosa collected in late 1972 in Vietnam, 4 had minimum inhibitory concentrations to chloramphenicol of >100 mug/ml. Median minimum inhibitory concentrations of all strains to oxolinic acid were 0.39 mug/ml; ampicillin, 6.25 mug/ml; amoxicillin, 0.39 mug/ml. Widespread typhoid fever appeared in mid-1973 with more than three-fourths of strains found to be resistant to chloramphenicol. Peak serum concentrations of oxolinic acid average 3.0 mug/ml after the oral ingestion of 1.0 g. In July 1974, a pilot study was begun to evaluate the efficacy of oxolinic acid in vivo, recognizing the discrepancy between in vitro and in vivo results with many agents evaluated in the treatment of typhoid fever. Seven patients with typhoid fever, six with positive blood cultures, were treated with oxolinic acid (1.5 g twice daily by mouth, a daily dose that averaged 75 mg/kg per day) for 5 to 12 days. In four of six patients, blood cultures became negative at 2 to 3 days, with another being negative at 6 days. Despite negative blood cultures, all but one patient remained clinically ill with temperatures of >39.5 C at 4 to 9 days. All strains were susceptible to 0.19 mug of oxolinic acid per ml, and resistant strains did not occur. One patient died after being changed to ampicillin, one left against advice, three responded to amoxicillin, and one died with pseudomonas bacteremia. Toxicity to oxolinic acid did not occur.
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Editorial: Treatment of typhoid fever and typhoid carriers in Southeast Asia: -Viewpoint form South Vietnam. Drugs 1975; 9:241-3. [PMID: 1126307 DOI: 10.2165/00003495-197509040-00001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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