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101.
Dung T. Nguyen Lan T. Pham Ha T. T. Le Minh X. Vu Hanh T.
M. Le Huong T. M. Le Nam H. Pham Le T. Lu 《RSC advances》2018,8(35):19707
Magnetic nanoparticles have received much interest for their application in wastewater treatment because of their easy retrieval and reuse. However, the methods used to synthesise high saturation magnetization magnetic nanoparticles require expensive and pure precursors. In the current study, we explore the potential for using spent pickling liquor, a wastewater solution from steel factories, as the iron precursor for preparing iron oxide nanoparticles. Here, magnetic Fe3O4 nanoparticles were synthesized via the oxidation–precipitation of spent pickling liquors using a saturated solution of calcium hydroxide at room temperature. The Fe3O4 nanoparticles were then modified with antibacterial polyguanidine to form a nanocomposite. It was found that monodisperse magnetic Fe3O4 nanoparticles with a size in the range 20–30 nm and a high saturation magnetization value of 73.9 emu g−1 were synthesised. The Fe3O4 nanoparticles were successfully encapsulated with polyguanidine to form an Fe3O4/polyguanidine nanocomposite. FT-IR and TGA analysis results indicated the presence of the polymer on the Fe3O4 surface and the polymer content in the nanocomposite was about 15% (w/w). The Fe3O4/polyguanidine nanocomposite exhibited strong antibacterial activity against Escherichia coli (E. coli), demonstrating its potential for use in disinfecting wastewater.An Fe3O4/polyguanidine nanocomposite with strong antibacterial activity was prepared from Fe3O4 nanoparticles, using spent pickling liquors as the iron source, which were then encapsulated with polyguanidine. 相似文献
102.
Alterations in erythrocyte rheology in patients with severe peripheral vascular disease: 1. Cell volume dependence of erythrocyte rigidity 总被引:1,自引:0,他引:1
The erythrocyte rigidity of patients suffering from severe peripheral vascular disease (PVD) was measured by a filtration method using 3 microns pore size filters. Filtration pressures for both PVD patients and normal subjects showed a cell volume dependency, and patient filtration pressures were normalized to cell volume to evaluate intrinsic, ie, nonvolume dependent, abnormalities in erythrocyte deformability. A significant (p less than 0.001) increase in cell rigidity was found in 44 of 54 PVD patients in comparison with volume-matched normal controls. No significant difference was found between patient mean corpusculer hemoglobin (MCH) and normal MCH at any given mean corpuscular volume (MCV), indicating that observed increases in erythrocyte rigidity are not attributable to changes in patient MCH. Therefore, the mechanism of increase in erythrocyte rigidity for PVD patients still needs further investigation into such parameters as levels of adenosine triphosphate,2,3-DPG, and membrane fluidity (calcium- and/or protein-binding membrane, cholesterol and phospholipid content of membrane, etc), as well as other aspects of erythrocyte physiology. 相似文献
103.
There is still debate on whether inflammatory pseudotumor should be considered benign or malignant. This lesion has only been reported twice in bone, apart from cases complicating foreign body reaction to joint replacement arthroplasty. We report here a third case, localized at the sacrum. A 31-year-old man had inflammatory dorsalgia and polyarthralgia without synovitis but with fever, asthenia, and erythema nodosa. Biological tests and X-rays were not informative, but technetium scintigraphy revealed a high level of left sacroiliac tracer binding. Several nonsteroidal anti-inflammatory drugs and sulfasalazine treatment were given over 3 months but ineffective. Pelvic magnetic resonance imaging showed an osteolytic tumor of the sacrum. Biopsy suggested a malignant fibrosarcoma, but complete evaluation after surgical resection demonstrated an inflammatory pseudotumor. All clinical symptoms disappeared within a few days after surgery, which is suggestive of a paraneoplastic syndrome. No relapse has occurred after 4 years. 相似文献
104.
C. Augereau D. Pham Dinh A. Moncion C. Marsac J. M. Saudubray B. H. Robinson 《Journal of inherited metabolic disease》1985,8(2):59-62
Pyruvate carboxylase (PC) deficiencies (McKusick 26615) are heterogeneous clinically and biochemically. We performed a complementation study with fibroblast strains from seven patients, (four patients with French phenotype, two patients with American phenotype, one patient with biotin responsive multiple carboxylase deficiency, MCD). The six isolated pyruvate carboxylase mutants (two cross-reacting material CRM –ve and four CRM +ve) failed to complement each other, but did complement a form of biotin responsive MCD. 相似文献
105.
Inflammation is an important component of active atherosclerotic disease. C-reactive protein (CRP)is a non-specific inflammatory marker that is increased in inflammatory conditions. Newer more sensitive assays (high sensitivity CRP) can detect the low levels of inflammation associated with vascular disease. CRP levels can give further risk assessment to individuals beyond predictions from traditional risk factors. This measurement is most useful in helping to discriminate risk in intermediate risk patients such as metabolic syndrome patients. Exercise and weight loss have been shown to significantly lower CRP levels. Lipid lowering therapies, especially with the statin class of medications, also lower CRP levels. A reduction in inflammation may be an important component of plaque stabilization and contribute to cardiovascular risk reduction. 相似文献
106.
107.
Shawn R. Lockhart Cau D. Pham Lalitha Gade Naureen Iqbal Christina M. Scheel Angela A. Cleveland Anne M. Whitney Judith Noble-Wang Tom M. Chiller Benjamin J. Park Anastasia P. Litvintseva Mary E. Brandt 《Journal of clinical microbiology》2013,51(8):2654-2661
In September 2012, the Centers for Disease Control and Prevention (CDC) initiated an outbreak investigation of fungal infections linked to injection of contaminated methylprednisolone acetate (MPA). Between 2 October 2012 and 14 February 2013, the CDC laboratory received 799 fungal isolates or human specimens, including cerebrospinal fluid (CSF), synovial fluid, and abscess tissue, from 469 case patients in 19 states. A novel broad-range PCR assay and DNA sequencing were used to evaluate these specimens. Although Aspergillus fumigatus was recovered from the index case, Exserohilum rostratum was the primary pathogen in this outbreak and was also confirmed from unopened MPA vials. Exserohilum rostratum was detected or confirmed in 191 specimens or isolates from 150 case patients, primarily from Michigan (n = 67 patients), Tennessee (n = 26), Virginia (n = 20), and Indiana (n = 16). Positive specimens from Michigan were primarily abscess tissues, while positive specimens from Tennessee, Virginia, and Indiana were primarily CSF. E. rostratum antifungal susceptibility MIC50 and MIC90 values were determined for voriconazole (1 and 2 μg/ml, respectively), itraconazole (0.5 and 1 μg/ml), posaconazole (0.5 and 1 μg/ml), isavuconazole (4 and 4 μg/ml), and amphotericin B (0.25 and 0.5 μg/ml). Thirteen other mold species were identified among case patients, and four other fungal genera were isolated from the implicated MPA vials. The clinical significance of these other fungal species remains under investigation. The laboratory response provided significant support to case confirmation, enabled linkage between clinical isolates and injected vials of MPA, and described significant features of the fungal agents involved in this large multistate outbreak. 相似文献
108.
Azumi Ishizaki Kaori Matsushita Huyen Thi Thanh Hoang Dorothy M. Agdamag Cuong Hung Nguyen Vuong Thi Tran Toshiyuki Sasagawa Kunikazu Saikawa Raphael Lihana Hung Viet Pham Xiuqiong Bi Van Thanh Ta Thuc Van Pham Hiroshi Ichimura 《Journal of medical virology》2013,85(6):1069-1076
Human papillomavirus (HPV) has several intragenotypic variants with different geographical and ethnic distributions. This study aimed to elucidate the distribution patterns of E6 and E7 (E6/E7) intragenotypic variants of HPV type 16 (HPV‐16), which is most common worldwide, and HPV‐52, which is common in Asian countries such as Japan, the Philippines, and Vietnam. In previous studies, genomic DNA samples extracted from cervical swabs were collected from female sex workers in these three countries and found to be positive for HPV‐16 or HPV‐52. Samples were amplified further for their E6/E7 genes using type‐specific primers and analyzed genetically. Seventy‐nine HPV‐16 E6/E7 genes were analyzed successfully and grouped into three lineages: European (Prototype), European (Asian), and African‐2. The prevalences of HPV‐16 European (Prototype)/European (Asian) lineages were 19.4%/80.6% (n = 31) in Japan, 75.0%/20.8% (n = 24) in the Philippines, and 0%/95.8% (n = 24) in Vietnam. The 109 HPV‐52 E6/E7 genes analyzed successfully were grouped into four lineages, A–D; the prevalences of lineages A/B/C/D were, respectively, 5.1%/92.3%/0%/2.6% in Japan (n = 39), 34.4%/62.5%/0%/3.1% in the Philippines (n = 32), and 15.8%/73.7%/7.9%/2.6% in Vietnam (n = 38). The distribution patterns of HPV‐16 and HPV‐52 lineages in these countries differed significantly (P < 0.000001 and P = 0.0048, respectively). There was no significant relationship between abnormal cervical cytology and either HPV‐16 E6/E7 lineages or specific amino acid mutations, such as E6 D25E, E6 L83V, and E7 N29S. Analysis of HPV‐16 and HPV‐52 E6/E7 genes can be a useful molecular‐epidemiological tool to distinguish geographical diffusion routes of these HPV types in Asia. J. Med. Virol. 85: 1069–1076, 2013. © 2013 Wiley Periodicals, Inc. 相似文献
109.
Nobuhiro Takemae Tung Nguyen Long Thanh Ngo Yasuaki Hiromoto Yuko Uchida Vu Phong Pham Tsutomu Kageyama Shizuko Kasuo Shinichi Shimada Yasutaka Yamashita Kaoru Goto Hideyuki Kubo Vu Tri Le Hung Van Vo Hoa Thi Do Dang Hoang Nguyen Tsuyoshi Hayashi Aya Matsuu Takehiko Saito 《Archives of virology》2013,158(4):859-876
The antigenicity of the influenza A virus hemagglutinin is responsible for vaccine efficacy in protecting pigs against swine influenza virus (SIV) infection. However, the antigenicity of SIV strains currently circulating in Japan and Vietnam has not been well characterized. We examined the antigenicity of classical H1 SIVs, pandemic A(H1N1)2009 (A(H1N1)pdm09) viruses, and seasonal human-lineage SIVs isolated in Japan and Vietnam. A hemagglutination inhibition (HI) assay was used to determine antigenic differences that differentiate the recent Japanese H1N2 and H3N2 SIVs from the H1N1 and H3N2 domestic vaccine strains. Minor antigenic variation between pig A(H1N1)pdm09 viruses was evident by HI assay using 13 mAbs raised against homologous virus. A Vietnamese H1N2 SIV, whose H1 gene originated from a human strain in the mid-2000s, reacted poorly with post-infection ferret serum against human vaccine strains from 2000-2010. These results provide useful information for selection of optimal strains for SIV vaccine production. 相似文献
110.
Masatoshi Okamatsu Tatsuya Nishi Naoki Nomura Naoki Yamamoto Yoshihiro Sakoda Kenji Sakurai Huy Duc Chu Long Pham Thanh Long Van Nguyen Nam Van Hoang Tien Ngoc Tien Reiko Yoshida Ayato Takada Hiroshi Kida 《Virus genes》2013,47(2):317-329
To estimate the prevalence of avian influenza virus infection in Vietnam, surveillance was conducted in domestic and wild birds from households, live-bird markets, slaughtering sites, and bird sanctuaries in Vietnam between October 2010 and October 2012. Of the 4,550 samples collected, 226 influenza A virus isolates were obtained from domestic ducks, muscovy ducks, and chickens. Of these, 25 and 22 H5N1 highly pathogenic avian influenza viruses (HPAIVs) were isolated from apparently healthy domestic ducks in live-bird markets and slaughtering sites in northern and southern Vietnam, respectively. The HA genes of H5 viruses isolated from birds in northern Vietnam phylogenetically belonged to the genetic clade 2.3.2.1 and those in southern Vietnam belonged to the genetic clade 1.1. In addition, 39 H3, 12 H4, 1 H5, 93 H6, 2 H7, 18 H9, 3 H10, and 11 H11 viruses were isolated. Phylogenetic and antigenic analyses of the H6 and H9 viruses revealed that they were closely related to the isolates obtained from domestic poultry in China. Phylogenetic analyses of internal gene segments of these isolates revealed that these viruses were circulating in both domestic and wild birds in Asia and reassortment events had occurred frequently. Therefore, it will be important to continue the surveillance and strict controls over the movement and trade of poultry and poultry products in order to eradicate H5N1 HPAIV from Asia. 相似文献