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1.
Lett Appl Microbiol ; 72(3): 275-282, 2021 Mar.
Article in English | MEDLINE | ID: mdl-33099779

ABSTRACT

Colistin is one of the antibiotics of last resort for human health. However, the dissemination of the plasmid-mediated colistin resistance gene mcr-1 is of great concern globally. In the One Health framework, the environment is an important component for managing antimicrobial resistance. However, little information is available concerning the prevalence of mcr-1 in water environments. We aimed to reveal the prevalence of mcr-1 in different water environments in Hanoi, Vietnam. Quantitative PCR was applied to detect mcr-1 in four urban drainages receiving untreated domestic wastewater, three rivers, five lakes and two groundwater samples. Urban drainages contained higher concentrations of mcr-1, suggesting that urban residents carry the gene. The class 1 integron-integrase gene was identified as a good surrogate of antibiotic resistance genes including mcr-1. A significant correlation was found between the levels of mcr-1 and the human-specific cross-assembly phage, which is an indicator of human faecal pollution. These results indicated that the primary source of mcr-1 in urban water environments is human faeces, which is consistent with the fact that most domestic wastewater is untreated in Hanoi. The control of untreated wastewater is critical for alleviating the spread of mcr-1 in water environments in Vietnam.


Subject(s)
Anti-Bacterial Agents/pharmacology , Colistin/pharmacology , Drug Resistance, Bacterial/genetics , Escherichia coli Proteins/genetics , Escherichia coli/genetics , Escherichia coli/drug effects , Escherichia coli Proteins/metabolism , Feces/microbiology , Humans , Lakes/microbiology , Plasmids/genetics , Rivers/microbiology , Vietnam , Wastewater/microbiology
2.
J Appl Microbiol ; 129(6): 1530-1540, 2020 Dec.
Article in English | MEDLINE | ID: mdl-32681543

ABSTRACT

AIMS: A continuous quench-flow (CQF) reactor was developed to collect samples at the reaction times of less than one second. The reactor is applied to determine ozone disinfection kinetics of poliovirus and to study whether EMA-qPCR can assess the viral infectivity after ozone disinfection. METHODS: Ozone disinfection of poliovirus was conducted in the developed CQF, and the disinfection kinetics were tested in the range of 0·7-5·0 s at ozone concentration of 0·08 and 0·25 mg l-1 . Inactivation, damage on viral genome and damage on capsid integrity were determined by plaque assay, quantitative reverse transcription polymerase chain reaction (RT-qPCR) and ethidium monoazide treatment coupled with RT-qPCR (EMA-qPCR), respectively. RESULTS: By using CQF, 2·18 and 2·76 log10 reductions were observed at the reaction time of 0·7 s and ozone concentration of 0·08 and 0·25 mg l-1 , respectively, followed by tailing. Ozone disinfection kinetics of poliovirus 1 were better fit by the efficiency factor Hom model than by the Chick-Watson model, or the modified Chick-Watson model. Kinetics observed were similar between RT-qPCR and EMA-qPCR assays at the reaction times of <2·0 s and ozone concentrations of 0·08 and 0·25 mg l-1 . At reaction times > 5 s, viral concentration evaluated by EMA-qPCR was reduced in comparison to stable RT-qPCR results. Both assays still underestimated the virus inactivation. CONCLUSION: The simple developed reactor can be used to investigate viral ozone disinfection kinetics and to elucidate inactivation characteristics or mechanisms at very short exposure times. SIGNIFICANCE AND IMPACT OF THE STUDY: The developed CQF reactor is beneficial for better understanding of virus inactivation by ozone, and the reactor can be used to better elucidate disinfection kinetics and mechanisms for future research. This work constitutes an important contribution to the existing knowledge of the application and limitation of the EMA/PMA-qPCR to assess virus infectivity after ozone disinfection.


Subject(s)
Disinfection , Ozone/pharmacology , Poliovirus/drug effects , Poliovirus/physiology , Azides , Capsid/drug effects , Disinfection/methods , Genome, Viral/drug effects , Kinetics , Poliovirus/genetics , Poliovirus/growth & development , Real-Time Polymerase Chain Reaction , Viral Plaque Assay , Virus Inactivation
3.
Ann Oncol ; 30(12): 1950-1958, 2019 12 01.
Article in English | MEDLINE | ID: mdl-31566666

ABSTRACT

BACKGROUND: Gemcitabine plus cisplatin (GC) is the standard treatment of advanced biliary tract cancer (BTC); however, it causes nausea, vomiting, and anorexia, and requires hydration. Gemcitabine plus S-1 (GS) reportedly has equal to, or better, efficacy and an acceptable toxicity profile. We aimed to confirm the non-inferiority of GS to GC for patients with advanced/recurrent BTC in terms of overall survival (OS). PATIENTS AND METHODS: We undertook a phase III randomized trial in 33 institutions in Japan. Eligibility criteria included chemotherapy-naïve patients with recurrent or unresectable BTC, an Eastern Cooperative Oncology Group Performance Status of 0 - 1, and adequate organ function. The calculated sample size was 350 with a one-sided α of 5%, a power of 80%, and non-inferiority margin hazard ratio (HR) of 1.155. The primary end point was OS, while the secondary end points included progression-free survival (PFS), response rate (RR), adverse events (AEs), and clinically significant AEs defined as grade ≥2 fatigue, anorexia, nausea, vomiting, oral mucositis, or diarrhea. RESULTS: Between May 2013 and March 2016, 354 patients were enrolled. GS was found to be non-inferior to GC [median OS: 13.4 months with GC and 15.1 months with GS, HR, 0.945; 90% confidence interval (CI), 0.78-1.15; P = 0.046 for non-inferiority]. The median PFS was 5.8 months with GC and 6.8 months with GS (HR 0.86; 95% CI 0.70-1.07). The RR was 32.4% with GC and 29.8% with GS. Both treatments were generally well-tolerated. Clinically significant AEs were observed in 35.1% of patients in the GC arm and 29.9% in the GS arm. CONCLUSIONS: GS, which does not require hydration, should be considered a new, convenient standard of care option for patients with advanced/recurrent BTC. CLINICAL TRIAL NUMBER: This trial has been registered with the UMIN Clinical Trials Registry (http://www.umin.ac.jp/ctr/index.htm), number UMIN000010667.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/administration & dosage , Biliary Tract Neoplasms/drug therapy , Cisplatin/administration & dosage , Deoxycytidine/analogs & derivatives , Adult , Aged , Antineoplastic Combined Chemotherapy Protocols/adverse effects , Biliary Tract Neoplasms/epidemiology , Biliary Tract Neoplasms/pathology , Cisplatin/adverse effects , Deoxycytidine/administration & dosage , Deoxycytidine/adverse effects , Disease-Free Survival , Drug Combinations , Female , Humans , Japan/epidemiology , Male , Middle Aged , Nausea/chemically induced , Nausea/pathology , Oxonic Acid/administration & dosage , Oxonic Acid/adverse effects , Tegafur/administration & dosage , Tegafur/adverse effects , Vomiting/chemically induced , Vomiting/pathology , Gemcitabine
4.
Radiat Environ Biophys ; 58(1): 1-11, 2019 03.
Article in English | MEDLINE | ID: mdl-30446811

ABSTRACT

Direct quantitative assessment of health risks following exposure to ionizing radiation is based on findings from epidemiological studies. Populations affected by nuclear bomb testing are among those that allow such assessment. The population living around the former Soviet Union's Semipalatinsk nuclear test site is one of the largest human cohorts exposed to radiation from nuclear weapons tests. Following research that started in the 1960s, a registry that contains information on more than 300,000 individuals residing in the areas neighboring to the test site was established. Four nuclear weapons tests, conducted from 1949 to 1956, resulted in non-negligible radiation exposures to the public, corresponding up to approximately 300 mGy external dose. The registry contains relevant information about those who lived at the time of the testing as well as about their offspring, including biological material. An international group of scientists worked together within the research project SEMI-NUC funded by the European Union, and concluded that the registry provides a novel, mostly unexplored, and valuable resource for the assessment of the population risks associated with environmental radiation exposure. Suggestions for future studies and pathways on how to use the best dose assessment strategies have also been described in the project. Moreover, the registry could be used for research on other relevant public health topics.


Subject(s)
Radiation Dosage , Radiobiology/methods , Registries , Automation , Kazakhstan
5.
Eur J Surg Oncol ; 43(10): 1956-1961, 2017 Oct.
Article in English | MEDLINE | ID: mdl-28747249

ABSTRACT

BACKGROUND: There have been no reports evaluating progression-free survival (PFS) as a surrogate endpoint in resectable esophageal cancer. This study was conducted to evaluate the trial level correlations between PFS and overall survival (OS) in resectable esophageal cancer with preoperative therapy and to explore the potential benefit of PFS as a surrogate endpoint for OS. METHODS: A systematic literature search of randomized trials with preoperative chemotherapy or preoperative chemoradiotherapy for esophageal cancer reported from January 1990 to September 2014 was conducted using PubMed and the Cochrane Library. Weighted linear regression using sample size of each trial as a weight was used to estimate coefficient of determination (R2) within PFS and OS. The primary analysis included trials in which the HR for both PFS and OS was reported. The sensitivity analysis included trials in which either HR or median survival time of PFS and OS was reported. In the sensitivity analysis, HR was estimated from the median survival time of PFS and OS, assuming exponential distribution. RESULTS: Of 614 articles, 10 trials were selected for the primary analysis and 15 for the sensitivity analysis. The primary analysis did not show a correlation between treatment effects on PFS and OS (R2 0.283, 95% CI [0.00-0.90]). The sensitivity analysis did not show an association between PFS and OS (R2 0.084, 95% CI [0.00-0.70]). CONCLUSION: Although the number of randomized controlled trials evaluating preoperative therapy for esophageal cancer is limited at the moment, PFS is not suitable for primary endpoint as a surrogate endpoint for OS.


Subject(s)
Biomarkers, Tumor/metabolism , Clinical Trials as Topic , Esophageal Neoplasms , Preoperative Care/methods , Biomarkers/metabolism , Combined Modality Therapy , Disease-Free Survival , Esophageal Neoplasms/metabolism , Esophageal Neoplasms/mortality , Esophageal Neoplasms/therapy , Global Health , Humans , Survival Rate/trends
6.
J Obstet Gynaecol Res ; 42(6): 707-15, 2016 Jun.
Article in English | MEDLINE | ID: mdl-26913817

ABSTRACT

AIM: The optimal treatment for pelvic organ prolapse has been the subject of much discussion. The aim of this study was to assess the utility of a combination of uterosacral colpopexy and anterior vaginal mesh implantation. METHODS: A single-center prospective cohort study was conducted. Twenty-eight patients with stage III-IV cystocele and uterine prolapse underwent reconstructive surgery. A combination of vaginal hysterectomy, McCall culdeplasty, and trocar-guided anterior vaginal mesh implantation was performed, and the patients' postoperative outcomes were analyzed. Patient satisfaction was investigated using the modified Short Form 12 version 2 (SF-12v2) questionnaire, and interviews regarding sexual behavior were conducted at 1 postoperative year. RESULTS: A bladder injury occurred during the dissection in one case (3.6%). Recurrent vaginal vault prolapse beyond the hymen was observed in one patient (cure rate: 96.4%), and further mesh augmentation was required in this case. Another patient developed mild cystocele (Ba = 0), but was simply observed because she did not complain of any symptoms caused by vaginal descent. We did not experience any other mesh-related complications, such as protrusion, chronic pain, or chronic inflammation, during the follow-up period. The patients' modified SF-12 scores at 12 months were significantly better than their preoperative scores in all eight domains. CONCLUSION: The satisfactory correction of pelvic organ prolapse was achieved using a combination of vaginal hysterectomy and uterosacral ligament colpopexy augmented by anterior vaginal mesh implantation. © 2016 Japan Society of Obstetrics and Gynecology.


Subject(s)
Hysterectomy, Vaginal/methods , Pelvic Organ Prolapse/surgery , Plastic Surgery Procedures/methods , Aged , Cystocele/epidemiology , Female , Humans , Intraoperative Complications/epidemiology , Middle Aged , Patient Satisfaction , Postoperative Complications/epidemiology , Prospective Studies , Treatment Outcome
7.
Food Environ Virol ; 6(4): 269-75, 2014 Dec.
Article in English | MEDLINE | ID: mdl-25106777

ABSTRACT

The damage to a viral capsid after low-pressure (LP) and medium-pressure (MP) UV irradiation was assessed, using the quantitative or quantitative reverse transcription PCR coupled with ethidium monoazide treatment (EMA-PCR). After UV irradiation, adenovirus 5 (Ad5) and poliovirus 1 (PV1) were subjected to a plaque assay, PCR, and EMA-PCR to investigate the effect of UV irradiation on viral infectivity, genome damage, and capsid damage, respectively. The effectiveness of UV wavelengths in a viral genome and capsid damage of both PV1 and Ad5 was also further investigated using a band-pass filter. It was found that an MPUV lamp was more effective than an LPUV lamp in inactivating Ad5, whereas there was no difference in the case of PV1. The results of viral reduction determined by PCR and EMA-PCR indicated that MP UV irradiation damaged Ad5 capsid. The damage to PV1 and Ad5 capsid was also not observed after LP UV irradiation. The investigation of effects of UV wavelengths suggested that UV wavelengths at 230-245 nm have greater effects on adenovirus capsid in addition to viral genome than UV wavelengths beyond 245 nm.


Subject(s)
Adenoviruses, Human/radiation effects , Affinity Labels/pharmacology , Azides/pharmacology , Capsid/radiation effects , Disinfection/methods , Genome, Viral/radiation effects , Poliovirus/radiation effects , Adenoviruses, Human/growth & development , Adenoviruses, Human/metabolism , Adenoviruses, Human/pathogenicity , Animals , Capsid/metabolism , Cell Line , Chlorocebus aethiops , DNA, Viral/metabolism , DNA, Viral/radiation effects , Humans , Poliovirus/growth & development , Poliovirus/metabolism , Poliovirus/pathogenicity , Pressure , RNA, Viral/metabolism , RNA, Viral/radiation effects , Radiation Tolerance , Real-Time Polymerase Chain Reaction , Reverse Transcriptase Polymerase Chain Reaction , Ultraviolet Rays , Viral Plaque Assay , Virus Inactivation/radiation effects
8.
Protein Sci ; 22(5): 586-94, 2013 May.
Article in English | MEDLINE | ID: mdl-23494942

ABSTRACT

We have visualized by cryo-electron microscopy (cryo-EM) the complex of the anthrax protective antigen (PA) translocon and the N-terminal domain of anthrax lethal factor (LF(N) inserted into a nanodisc model lipid bilayer. We have determined the structure of this complex at a nominal resolution of 16 Å by single-particle analysis and three-dimensional reconstruction. Consistent with our previous analysis of negatively stained unliganded PA, the translocon comprises a globular structure (cap) separated from the nanodisc bilayer by a narrow stalk that terminates in a transmembrane channel (incompletely distinguished in this reconstruction). The globular cap is larger than the unliganded PA pore, probably due to distortions introduced in the previous negatively stained structures. The cap exhibits larger, more distinct radial protrusions, previously identified with PA domain three, fitted by elements of the NMFF PA prepore crystal structure. The presence of LF(N), though not distinguished due to the seven-fold averaging used in the reconstruction, contributes to the distinct protrusions on the cap rim volume distal to the membrane. Furthermore, the lumen of the cap region is less resolved than the unliganded negatively stained PA, due to the low contrast obtained in our images of this specimen. Presence of the LF(N) extended helix and N terminal unstructured regions may also contribute to this additional internal density within the interior of the cap. Initial NMFF fitting of the cryoEM-defined PA pore cap region positions the Phe clamp region of the PA pore translocon directly above an internal vestibule, consistent with its role in toxin translocation.


Subject(s)
Anthrax/microbiology , Antigens, Bacterial/chemistry , Antigens, Bacterial/ultrastructure , Bacillus anthracis/chemistry , Bacterial Toxins/chemistry , Bacillus anthracis/ultrastructure , Cryoelectron Microscopy , Lipid Bilayers/chemistry
9.
Protein Sci ; 22(4): 492-501, 2013 Apr.
Article in English | MEDLINE | ID: mdl-23389868

ABSTRACT

We have devised a procedure to incorporate the anthrax protective antigen (PA) pore complexed with the N-terminal domain of anthrax lethal factor (LFN ) into lipid nanodiscs and analyzed the resulting complexes by negative-stain electron microscopy. Insertion into nanodiscs was performed without relying on primary and secondary detergent screens. The preparations were relatively pure, and the percentage of PA pore inserted into nanodiscs on EM grids was high (∼43%). Three-dimensional analysis of negatively stained single particles revealed the LFN -PA nanodisc complex mirroring the previous unliganded PA pore nanodisc structure, but with additional protein density consistent with multiple bound LFN molecules on the PA cap region. The assembly procedure will facilitate collection of higher resolution cryo-EM LFN -PA nanodisc structures and use of advanced automated particle selection methods.


Subject(s)
Antigens, Bacterial/ultrastructure , Lipids/chemistry , Nanostructures/ultrastructure , Antigens, Bacterial/metabolism , Bacterial Toxins/metabolism , Cryoelectron Microscopy , Models, Molecular , Recombinant Proteins/chemistry , Recombinant Proteins/metabolism
10.
Neoplasma ; 60(2): 135-42, 2013.
Article in English | MEDLINE | ID: mdl-23259781

ABSTRACT

Incidence and mortality associated with hepatocellular carcinoma (HCC) is rising throughout the world. Accurate, noninvasive biomarkers for the early detection of HCC are urgently needed to reduce worldwide morbidity and mortality related to HCC. MicroRNAs (miRNAs), 17- to 25-nucleotide noncoding RNAs that are frequently dysregulated in HCC, have shown great promise as tissue-based markers for HCC diagnosis and prognosis. Moreover, they are stably expressed in serum and urine, and these circulating microRNAs (cmiRNAs) are emerging as novel noninvasive biomarkers for the early detection and prognosis of HCC. This article summarizes the latest findings on the role of circulating miRNAs as potential minimally invasive diagnostic and prognostic biomarkers for HCC.


Subject(s)
Biomarkers, Tumor/blood , Carcinoma, Hepatocellular/diagnosis , Liver Neoplasms/diagnosis , MicroRNAs/blood , Carcinoma, Hepatocellular/blood , Humans , Liver Neoplasms/blood , Prognosis
11.
J Appl Microbiol ; 114(2): 545-54, 2013 Feb.
Article in English | MEDLINE | ID: mdl-23170920

ABSTRACT

AIMS: To evaluate and compare the reductions of human viruses and F-specific coliphages in a full-scale wastewater treatment plant based on the quantitative PCR (qPCR) and plate count assays. METHODS AND RESULTS: A total of 24 water samples were collected from four locations at the plant, and the relative abundance of human viruses and F-RNA phage genogroups were determined by qPCR. Of the 10 types of viruses tested, enteric adenoviruses were the most prevalent in both influent and effluent wastewater samples. Of the different treatment steps, the activated sludge process was most effective in reducing the microbial loads. Viruses and F-RNA phages showed variable reduction; among them, GI and GIII F-RNA phages showed the lowest and the highest reduction, respectively. CONCLUSIONS: Ten types of viruses were present in wastewater that is discharged into public water bodies after treatment. The variability in reduction for the different virus types demonstrates that selection of adequate viral indicators is important for evaluating the efficacy of wastewater treatment and ensuring the water safety. SIGNIFICANCE AND IMPACT OF THE STUDY: Our comprehensive analyses of the occurrence and reduction of viruses and indicators can contribute to the future establishment of appropriate viral indicators to evaluate the efficacy of wastewater treatment.


Subject(s)
Coliphages/isolation & purification , RNA Phages/isolation & purification , Wastewater/virology , Coliphages/genetics , Japan , Polymerase Chain Reaction/methods , RNA Phages/genetics , Sewage/virology , Waste Disposal Facilities , Wastewater/microbiology , Water Microbiology , Water Purification
12.
Radiat Prot Dosimetry ; 151(4): 677-81, 2012 Oct.
Article in English | MEDLINE | ID: mdl-22914332

ABSTRACT

Many studies have been conducted by the Radiation Effects Research Foundation (RERF) to assess the radiation effects on human beings of atomic bombs, and numerous data have been collected, including records of medical examinations and questionnaires, analytical results, inventories of biosamples and published or unpublished documentation. Some of those data have been stored and analysed since the Atomic Bomb Casualty Commission (later reorganised as RERF) was established in 1947. RERF has made an effort to establish an archival database system so that an RERF researcher can access data at any time without difficulty. Under development is a new database system with the capability to handle a very large amount of data and permit future bioinformatics analyses of data, such as that required in genomics and proteomics analyses.


Subject(s)
Nuclear Warfare , Nuclear Weapons , Humans , Japan , Neoplasms, Radiation-Induced , Proteomics , Surveys and Questionnaires
13.
Transplant Proc ; 44(1): 124-7, 2012 Jan.
Article in English | MEDLINE | ID: mdl-22310595

ABSTRACT

BACKGROUND: Graceptor is a new modified-release once-daily formulation of tacrolimus with an efficacy and safety profile similar to twice-daily tacrolimus (Prograf), as identified by clinical trials, offering a more convenient dosing regimen to improve adherence. The aim of this study was to analyze the safety of a 1:1 dose conversion from twice-daily Prograf to once-daily Graceptor in stable kidney transplant recipients. METHODS: We switched 33 Japanese patients who had undergone kidney transplantation ≥1 years before from twice-daily Prograf to once-daily Graceptor. The dose conversion ratio between Prograf and Graceptor was 1:1. We compared the following parameters: minimum tacrolimus concentration (C(min)); concentration dose per weight (CDW); serum creatinine (sCr); blood urea nitrogen (BUN); total cholesterol (TC); high-density lipoprotein cholesterol (HDL-C); uric acid (UA); fasting blood sugar (FBS). Time points for measurements were 1 month before study start and 1 and 2 months afterward. RESULTS: The mean age of the subjects in this study was 46.5 ± 13.1 years. Mean C(min) decreased from 4.55 ± 1.79 to 3.20 ± 1.22 ng/dL. The mean CDW also decreased, from 99.8 ± 69.5 to 75.0 ± 55.1 mg/dL/kg over the 2 months. There were no significant changes in sCR, BUN, UA, and FBS. Mean TC increased from 187.5 ± 51.4 to 194.3 ± 43.4 mg/dL, and mean HDL-C changed from 53.7 ± 12.0 to 56.1 ± 11 mg/dL. There were no episodes of rejection or infection. CONCLUSIONS: We conclude that switching from Prograf to Graceptor is safe and has the advantage of improving adherence. It could also have a beneficial effect in controlling glycemic levels and the adverse effects of tacrolimus. In many cases (25%-30%), the minimum concentration of tacrolimus decreased after changing tablets. With Graceptor, the ratio of area under trough level to area under the curve (AUC) is low compared with Prograf, resulting in low C(min) values of 1-2 ng/mL, and the AUC for Graceptor is very similar to that for Prograf.


Subject(s)
Immunosuppressive Agents/administration & dosage , Kidney Transplantation , Tacrolimus/administration & dosage , Adult , Biomarkers/blood , Delayed-Action Preparations , Drug Administration Schedule , Drug Monitoring , Female , Graft Rejection/blood , Graft Rejection/immunology , Graft Rejection/prevention & control , Graft Survival/drug effects , Humans , Immunosuppressive Agents/adverse effects , Immunosuppressive Agents/pharmacokinetics , Japan , Kidney Transplantation/immunology , Male , Medication Adherence , Middle Aged , Tacrolimus/adverse effects , Tacrolimus/pharmacokinetics , Treatment Outcome
14.
J Appl Microbiol ; 112(3): 605-13, 2012 Mar.
Article in English | MEDLINE | ID: mdl-22221550

ABSTRACT

AIMS: To investigate the prevalence, seasonality and genotype distribution of human noroviruses (NoVs) in wastewater in Japan. METHODS AND RESULTS: Influent and effluent water samples were collected monthly for a year from a wastewater treatment plant and examined for the presence of genogroups I and II (GI and GII) NoVs. Using real-time reverse transcription (RT)-PCR assays, 12 (100%) influent and six (50%) effluent samples were positive for both GI and GII NoV genomes, with a higher prevalence in winter. A total of 152 different NoV strains, comprising 84 GI and 68 GII strains, were identified using seminested RT-PCR assays followed by cloning and sequence analysis. These strains were classified into nine GI genotypes (GI/1, 2, 4, 5, 8, 9, 11, 12 and 14) and 13 GII genotypes (GII/1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 15 and 16), showing considerable genetic diversity. CONCLUSIONS: Based on the partial capsid gene sequences, we identified a great number of NoV strains belonging to many genotypes, demonstrating that genetically diverse NoV strains are co-circulating in aquatic environments and human populations. SIGNIFICANCE AND IMPACT OF THE STUDY: Our results clearly demonstrate the seasonal trend and genetic diversity of NoVs in wastewater.


Subject(s)
Genetic Variation , Norovirus/isolation & purification , Seasons , Waste Disposal, Fluid/methods , Water Purification/methods , Capsid Proteins/genetics , DNA, Viral/genetics , Genotype , Japan , Molecular Sequence Data , Norovirus/classification , Norovirus/genetics , Phylogeny , Real-Time Polymerase Chain Reaction , Reverse Transcriptase Polymerase Chain Reaction , Sequence Analysis, DNA , Water/analysis
15.
Lett Appl Microbiol ; 53(4): 438-44, 2011 Oct.
Article in English | MEDLINE | ID: mdl-21790679

ABSTRACT

AIMS: To develop time-dependent dose-response models for highly pathogenic avian influenza A (HPAI) of the H5N1 subtype virus. METHODS AND RESULTS: A total of four candidate time-dependent dose-response models were fitted to four survival data sets for animals (mice or ferrets) exposed to graded doses of HPAI H5N1 virus using the maximum-likelihood estimation. A beta-Poisson dose-response model with the N(50) parameter modified by an exponential-inverse-power time dependency or an exponential dose-response model with the k parameter modified by an exponential-inverse time dependency provided a statistically adequate fit to the observed survival data. CONCLUSIONS: We have successfully developed the time-dependent dose-response models to describe the mortality of animals exposed to an HPAI H5N1 virus. The developed model describes the mortality over time and represents observed experimental responses accurately. SIGNIFICANCE AND IMPACT OF THE STUDY: This is the first study describing time-dependent dose-response models for HPAI H5N1 virus. The developed models will be a useful tool for estimating the mortality of HPAI H5N1 virus, which may depend on time postexposure, for the preparation of a future influenza pandemic caused by this lethal virus.


Subject(s)
Influenza A Virus, H5N1 Subtype/pathogenicity , Orthomyxoviridae Infections/mortality , Animals , Disease Models, Animal , Ferrets , Mice , Models, Statistical , Orthomyxoviridae Infections/virology , Survival Analysis
16.
Water Sci Technol ; 63(6): 1224-9, 2011.
Article in English | MEDLINE | ID: mdl-21436560

ABSTRACT

Microcystis aeruginosa forms algal bloom in lakes. They produce toxic compounds such as microcystin. Against such algal problems, the effect of UV treatment was examined. In UV treatment, the effect of photoreactivation should be examined. Photoreactivation is a repair mechanism of genomic DNA damage by sunlight irradiation. UV treatment causes DNA damages on target cyanobacteria, however sunlight can repair some of these DNA damages. To examine the effect of photoreactivation, both white and yellow light incubations were employed. White light allows both photoreactivation and photosynthesis, while yellow light prohibits photoreactivation and only allows photosynthesis. Microcystis aeruginosa NIES 98 strain and PCC 7806 strain were used as the test cultures. Those cultures were exposed to low-pressure (LP) or medium-pressure (MP) ultraviolet (UV) lamp, then incubated under white or yellow light. Yellow light incubation method was effective to examine photoreactivation. It was revealed that almost six times UV fluence was required to inactivate 99% of Microcystis aeruginosa, under photoreactivation condition, compared with non-photoreactivation condition. Inhibition of photoreactivation could greatly enhance UV treatment efficiency against Microcystis aeruginosa. One of the practical suggestions is to conduct UV treatment at night, when photoreactivation by sunlight rarely takes place. Highly efficient inactivation was achieved by avoiding photoreactivation.


Subject(s)
DNA Damage/radiation effects , DNA Repair/radiation effects , Microcystis/radiation effects , Sunlight , Ultraviolet Rays , Water Microbiology , Time Factors , Water Purification
17.
Water Sci Technol ; 63(3): 502-7, 2011.
Article in English | MEDLINE | ID: mdl-21278473

ABSTRACT

A method was developed for discriminating damaged viruses or naked viral RNA from intact viruses by ethidium monoazide (EMA) treatment before RT-PCR. The applied EMA treatment consisted of three steps: (1) EMA dose, (2) exposure to light, and (3) additional purification by spin-column gel filtration. Approximately 4-log reduction in viral RNA concentration was observed by adding a dose of 10 µg/mL-EMA with 300 s of light irradiation. Although residual EMA can be an inhibitor of RT-PCR, its effect was reduced by spin-column gel filtration or a QIAamp® Viral RNA Mini Kit. EMA-RT-PCR was applied to the thermally treated PV1. Results of EMA-RT-PCR were similar to the plaque assay when PV1 was thermally inactivated. Although this is a preliminary study investigating applicability of the EMA-RT-PCR method for RNA viruses, the results suggest that the method is potentially applicable for the selective detection of epidemiologically important enteric viruses in water such as enteroviruses and noroviruses.


Subject(s)
Azides/pharmacology , Hot Temperature , RNA Viruses/drug effects , RNA, Viral/isolation & purification , Reverse Transcriptase Polymerase Chain Reaction/methods , Animals , Light , Mice , Norovirus/drug effects , Norovirus/genetics , Norovirus/isolation & purification , Norovirus/radiation effects , RNA Viruses/genetics , RNA Viruses/isolation & purification , RNA Viruses/radiation effects , RNA, Viral/genetics
18.
Lett Appl Microbiol ; 52(2): 181-4, 2011 Feb.
Article in English | MEDLINE | ID: mdl-21214607

ABSTRACT

AIMS: To investigate the prevalence, seasonality and genetic diversity of genogroup IV noroviruses (GIV NoVs) in wastewater in Japan. METHODS AND RESULTS: Untreated and treated wastewater samples were collected monthly for a year from a wastewater treatment plant in Japan. The concentrated wastewater samples were examined for the presence of GIV NoV genomes with seminested RT-PCR assay targeting partial capsid gene. Among 12 untreated and 12 treated wastewater samples tested, GIV NoV genomes were detected in three (25%) untreated and two (17%) treated wastewater samples with a high positive ratio in winter season. Genetic analysis revealed that the GIV NoVs in the wastewater samples were genetically diverse and were classified into three different genetic clusters. CONCLUSIONS: Frequent detection of GIV NoVs in winter season, which is a common epidemic period of human NoVs in Japan, indicates that GIV NoVs exhibit temporal trends similar to GI and GII NoVs. Based on the partial capsid gene sequences, we identified several unique GIV NoV strains belonging to the novel genetic cluster, demonstrating that GIV NoVs are more genetically diverse than previously appreciated. SIGNIFICANCE AND IMPACT OF THE STUDY: Our findings provide novel evidence of considerable genetic diversity among the GIV NoV strains.


Subject(s)
Norovirus/classification , Water Microbiology , Capsid Proteins/genetics , Genetic Variation , Genotype , Humans , Japan , Norovirus/genetics , Norovirus/isolation & purification , Phylogeny , Reverse Transcriptase Polymerase Chain Reaction , Seasons , Waste Disposal, Fluid
19.
Blood Cancer J ; 1(12): e46, 2011 Dec.
Article in English | MEDLINE | ID: mdl-22829094

ABSTRACT

Aberrant activation of the Janus kinase (JAK)/signal transducer and activator of transcription (STAT) pathway has been reported to promote proliferation and survival of Hodgkin and Reed-Sternberg cells of Hodgkin lymphoma (HL). We investigated the activity of the JAK inhibitor AZD1480 in HL-derived cell lines and determined its mechanisms of action. AZD1480 at low doses (0.1-1 µ) potently inhibited STATs phosphorylation, but did not predictably result in antiproliferative effects, as it activated a negative-feedback loop causing phosphorylation of JAK2 and extracellular signal-regulated kinases 1 and 2 (ERK1/2), and increased IP-10, RANTES and interleukin (IL)-8 concentrations in the supernatants. Inhibition of the ERK activity by mitogen-activated extracellular signal regulated kinase (MEK) inhibitors (UO126 and PD98059) enhanced the cytotoxic activity of AZD1480. Interestingly, submicromolar concentrations of AZD1480 demonstrated significant immunoregulatory effects by downregulating T-helper 2 cytokines and chemokines, including IL-13 and thymus- and activation-regulated chemokine, and the surface expression of the immunosuppressive programmed death ligands 1 and 2. Higher concentrations of AZD1480 (5 µ) induced G2/M arrest and cell death by inhibiting Aurora kinases. Our study demonstrates that AZD1480 regulates proliferation and immunity in HL cell lines and provides mechanistic rationale for evaluating AZD1480 alone or in combination with MEK inhibitors in HL.

20.
Lett Appl Microbiol ; 51(1): 119-21, 2010 Jul.
Article in English | MEDLINE | ID: mdl-20536708

ABSTRACT

AIMS: To evaluate the reduction of human norovirus (HuNoV) by chlorine disinfection under typical drinking water treatment conditions. METHODS AND RESULTS: HuNoV, murine norovirus (MNV) and poliovirus type 1 (PV1) were inoculated into treated water before chlorination, collected from a drinking water treatment plant, and bench-scale free chlorine disinfection experiments were performed for two initial free chlorine concentrations, 0.1 and 0.5 mg l(-1). Inactivation of MNV reached more than 4 log(10) after 120 and 0.5 min contact time to chlorine at the initial free chlorine concentrations of 0.1 and 0.5 mg l(-1), respectively. CONCLUSIONS: MNV was inactivated faster than PV1, and there was no significant difference in the viral RNA reduction rate between HuNoV and MNV. The results suggest that appropriate water treatment process with chlorination can manage the risk of HuNoV infection via drinking water supply systems. SIGNIFICANCE AND IMPACT OF THE STUDY: The data obtained in this study would be useful for assessing or managing the risk of HuNoV infections from drinking water exposure.


Subject(s)
Chlorine/pharmacology , Disinfectants/pharmacology , Disinfection/methods , Norovirus/drug effects , Poliovirus/drug effects , Water Microbiology , Water Purification/methods , Animals , Cell Line , Humans , Time Factors , Viral Load , Viral Plaque Assay , Virus Inactivation
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