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Low impact of infectious hypodermal and hematopoietic necrosis virus (IHHNV) on growth and reproductive performance of Penaeus monodon 总被引:1,自引:0,他引:1
Withyachumnarnkul B Chayaburakul K Lao-Aroon S Plodpai P Sritunyalucksana K Nash G 《Diseases of aquatic organisms》2006,69(2-3):129-136
No controlled studies on the effect of infectous hypodermal and necrosis virus (IHHNV) on Penaeus monodon have been previously reported. Here we describe domesticated P. monodon that became positive for IHHNV and other viruses at variable levels of prevalence during cultivation in 16 open-air, earthen ponds. These were stocked with domesticated postlarvae (PL) that tested negative for 7 shrimp viruses including IHHNV at 6% prevalence in 3 checks using polymerase chain reaction (PCR) methods. These PL were derived from domesticated female broodstock that individually tested negative for the same viruses. At 4 mo of culture, the shrimp in some ponds without obvious mortality tested positive by PCR methods for IHHNV and 3 other viruses at variable levels of maximum estimated prevalence (MEP). Stained tissue sections showed no lesions typical of IHHNV, but in situ hybridization tests with an IHHNV-specific DNA probe were positive. There was no significant difference in mean body weight (i.e. ca. 25 g) between shrimp groups positive or negative for IHHNV. Similar results were obtained with IHHNV negative and positive adults at 1 yr. Adults that individually tested negative for all 7 viruses and some that tested lightly positive for IHHNV were bred for the next generation. There were no significant differences in the number of eggs (> 600 000) and nauplii (ca. 300,000) produced by females negative and positive for IHHNV. From these females, 11/49 (22%) IHHNV PCR-positive PL batches were obtained from PCR-negative spawners, while 8/11 (73%) were obtained from IHHNV PCR-positive spawners. The results suggested that IHHNV infection can be transmitted vertically but does not seriously retard growth of P. monodon or affect fecundity of lightly infected broodstock. 相似文献
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Sirivichayakul C Limkittikul K Chanthavanich P Jiwariyavej V Chokejindachai W Pengsaa K Suvannadabba S Dulyachai W Letson GW Sabchareon A 《PLoS neglected tropical diseases》2012,6(2):e1520
Background
Dengue infection is one of the most important mosquito-borne diseases. More data regarding the disease burden and the prevalence of each clinical spectrum among symptomatic infections and the clinical manifestations are needed. This study aims to describe the incidence and clinical manifestations of symptomatic dengue infection in Thai children during 2006 through 2008.Study Design
This study is a school-based prospective open cohort study with a 9,448 person-year follow-up in children aged 3–14 years. Active surveillance for febrile illnesses was done in the studied subjects. Subjects who had febrile illness were asked to visit the study hospital for clinical and laboratory evaluation, treatment, and serological tests for dengue infection. The clinical data from medical records, diary cards, and data collection forms were collected and analyzed.Results
Dengue infections were the causes of 12.1% of febrile illnesses attending the hospital, including undifferentiated fever (UF) (49.8%), dengue fever (DF) (39.3%) and dengue hemorrhagic fever (DHF) (10.9%). Headache, anorexia, nausea/vomiting and myalgia were common symptoms occurring in more than half of the patients. The more severe dengue spectrum (i.e., DHF) had higher temperature, higher prevalence of nausea/vomiting, abdominal pain, rash, diarrhea, petechiae, hepatomegaly and lower platelet count. DHF cases also had significantly higher prevalence of anorexia, nausea/vomiting and abdominal pain during day 3–6 and diarrhea during day 4–6 of illness. The absence of nausea/vomiting, abdominal pain, diarrhea, petechiae, hepatomegaly and positive tourniquet test may predict non-DHF.Conclusion
Among symptomatic dengue infection, UF is most common followed by DF and DHF. Some clinical manifestations may be useful to predict the more severe disease (i.e., DHF). This study presents additional information in the clinical spectra of symptomatic dengue infection. 相似文献4.
Thanyada Rungrotmongkol Pathumwadee Intharathep Nadtanet Nunthaboot Pornthep Sompornpisut Yong Poovorawan 《Biochemical and biophysical research communications》2009,385(3):390-394
The recent outbreak of the novel strain of influenza A (H1N1) virus has raised a global concern of the future risk of a pandemic. To understand at the molecular level how this new H1N1 virus can be inhibited by the current anti-influenza drugs and which of these drugs it is likely to already be resistant to, homology modeling and MD simulations have been applied on the H1N1 neuraminidase complexed with oseltamivir, and the M2-channel with adamantanes bound. The H1N1 virus was predicted to be susceptible to oseltamivir, with all important interactions with the binding residues being well conserved. In contrast, adamantanes are not predicted to be able to inhibit the M2 function and have completely lost their binding with the M2 residues. This is mainly due to the fact that the M2 transmembrane of the new H1N1 strain contains the S31N mutation which is known to confer resistance to adamantanes. 相似文献
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Tatsaporn Todhanakasem Supanika Yodsanga Apinya Sowatad Pattanop Kanokratana Pornthep Thanonkeo Verawat Champreda 《Biotechnology and bioengineering》2018,115(1):70-81
Lignocellulose pretreatment produces various toxic inhibitors that affect microbial growth, metabolism, and fermentation. Zymomonas mobilis is an ethanologenic microbe that has been demonstrated to have potential to be used in lignocellulose biorefineries for bioethanol production. Z. mobilis biofilm has previously exhibited high potential to enhance ethanol production by presenting a higher viable cell number and higher metabolic activity than planktonic cells or free cells when exposed to lignocellulosic hydrolysate containing toxic inhibitors. However, there has not yet been a systematic study on the tolerance level of Z. mobilis biofilm compared to planktonic cells against model toxic inhibitors derived from lignocellulosic material. We took the first insight into the concentration of toxic compound (formic acid, acetic acid, furfural, and 5‐HMF) required to reduce the metabolic activity of Z. mobilis biofilm and planktonic cells by 25% (IC25), 50% (IC50), 75% (IC75), and 100% (IC100). Z. mobilis strains ZM4 and TISTR 551 biofilm were two‐ to three fold more resistant to model toxic inhibitors than planktonic cells. Synergetic effects were found in the presence of formic acid, acetic acid, furfural, and 5‐HMF. The IC25 of Z. mobilis ZM4 biofilm and TISTR 551 biofilm were 57 mm formic acid, 155 mm acetic acid, 37.5 mm furfural and 6.4 mm 5‐HMF, and 225 mm formic acid, 291 mm acetic acid, 51 mm furfural and 41 mm 5‐HMF, respectively. There was no significant difference found between proteomic analysis of the stress response to toxic inhibitors of Z. mobilis biofilm and planktonic cells on ZM4. However, TISTR 551 biofilms exhibited two proteins (molecular chaperone DnaK and 50S ribosomal protein L2) that were up‐regulated in the presence of toxic inhibitors. TISTR 551 planktonic cells possessed two types of protein in the group of 30S ribosomal proteins and motility proteins that were up‐regulated. 相似文献
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Malaisree Maturos Rungrotmongkol Thanyada Nunthaboot Nadtanet Aruksakunwong Ornjira Intharathep Pathumwadee Decha Panita Sompornpisut Pornthep Hannongbua Supot 《Amino acids》2009,37(4):725-732
Molecular dynamics simulations were carried out for the mutant oseltamivir-NA complex, to provide detailed information on
the oseltamivir-resistance resulting from the H274Y mutation in neuraminidase (NA) of avian influenza H5N1 viruses. In contrast
with a previous proposal, the H274Y mutation does not prevent E276 and R224 from forming the hydrophobic pocket for the oseltamivir
bulky group. Instead, reduction of the hydrophobicity and size of pocket in the area around an ethyl moiety at this bulky
group were found to be the source of the oseltamivir-resistance. These changes were primarily due to the dramatic rotation
of the hydrophilic –COO− group of E276 toward the ethyl moiety. In addition, hydrogen-bonding interactions with N1 residues at the -NH3
+ and -NHAc groups of oseltamivir were replaced by a water molecule. The calculated binding affinity of oseltamivir to NA was
significantly reduced from −14.6 kcal mol−1 in the wild-type to −9.9 kcal mol−1 in the mutant-type. 相似文献
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Thanyada Rungrotmongkol Thanyarat Udommaneethanakit Maturos Malaisree Nadtanet Nunthaboot Pathumwadee Intharathep Pornthep Sompornpisut Supot Hannongbua 《Biophysical chemistry》2009
To reveal the source of oseltamivir-resistance in influenza (A/H5N1) mutants, the drug-target interactions at each functional group were investigated using MD/LIE simulations. Oseltamivir in the H274Y mutation primarily loses the electrostatic and the vdW interaction energies at the –NH3+ and –OCHEt2 moieties corresponding to the weakened hydrogen-bonds and changed distances to N1 residues. Differentially, the N294S mutation showed small changes of binding energies and intermolecular interactions. Interestingly, the presence of different conformations of E276 positioned between the –OCHEt2 group and the mutated residue is likely to play an important role in oseltamivir-resistant identification. In the H274Y mutant, it moves towards the –OCHEt2 group leading to a reduction in hydrophobicity and pocket size, whilst in the N294S mutant it acts as the hydrogen network center bridging with R224 and the mutated residue S294. The molecular details have answered a question of how the H274Y and N294S mutations confer the high- and medium-level of oseltamivir-resistance to H5N1. 相似文献
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Woods CJ Malaisree M Pattarapongdilok N Sompornpisut P Hannongbua S Mulholland AJ 《Biochemistry》2012,51(21):4364-4375
Multidrug resistance of the pandemic H1N1-2009 strain of influenza has been reported due to widespread treatment using the neuraminidase (NA) inhibitors, oseltamivir (Tamiflu), and zanamivir (Relenza). From clinical data, the single I223R (IR(1)) mutant of H1N1-2009 NA reduced efficacy of oseltamivir and zanamivir by 45 and 10 times, (1) respectively. More seriously, the efficacy of these two inhibitors against the double mutant I223R/H275Y (IRHY(2)) was significantly reduced by a factor of 12?374 and 21 times, respectively, compared to the wild-type.(2) This has led to the question of why the efficacy of the NA inhibitors is reduced by the occurrence of these mutations and, specifically, why the efficacy of oseltamivir against the double mutant IRHY was significantly reduced, to the point where oseltamivir has become an ineffective treatment. In this study, 1 μs of molecular dynamics (MD) simulations was performed to answer these questions. The simulations, run using graphical processors (GPUs), were used to investigate the effect of conformational change upon binding of the NA inhibitors oseltamivir and zanamivir in the wild-type and the IR and IRHY mutant strains. These long time scale dynamics simulations demonstrated that the mechanism of resistance of IRHY to oseltamivir was due to the loss of key hydrogen bonds between the inhibitor and residues in the 150-loop. This allowed NA to transition from a closed to an open conformation. Oseltamivir binds weakly with the open conformation of NA due to poor electrostatic interactions between the inhibitor and the active site. The results suggest that the efficacy of oseltamivir is reduced significantly because of conformational changes that lead to the open form of the 150-loop. This suggests that drug resistance could be overcome by increasing hydrogen bond interactions between NA inhibitors and residues in the 150-loop, with the aim of maintaining the closed conformation, or by designing inhibitors that can form a hydrogen bond to the mutant R223 residue, thereby preventing competition between R223 and R152. 相似文献
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Source of high pathogenicity of an avian influenza virus H5N1: why H5 is better cleaved by furin 下载免费PDF全文
Decha P Rungrotmongkol T Intharathep P Malaisree M Aruksakunwong O Laohpongspaisan C Parasuk V Sompornpisut P Pianwanit S Kokpol S Hannongbua S 《Biophysical journal》2008,95(1):128-134
The origin of the high pathogenicity of an emerging avian influenza H5N1 due to the -RRRKK- insertion at the cleavage loop of the hemagglutinin H5, was studied using the molecular dynamics technique, in comparison with those of the noninserted H5 and H3 bound to the furin (FR) active site. The cleavage loop of the highly pathogenic H5 was found to bind strongly to the FR cavity, serving as a conformation suitable for the proteolytic reaction. With this configuration, the appropriate interatomic distances were found for all three reaction centers of the enzyme-substrate complex: the arrangement of the catalytic triad, attachment of the catalytic Ser368 to the reactive S1-Arg, and formation of the oxyanion hole. Experimentally, the -RRRKK- insertion was also found to increase in cleavage of hemagglutinin by FR. The simulated data provide a clear answer to the question of why inserted H5 is better cleaved by FR than the other subtypes, explaining the high pathogenicity of avian influenza H5N1. 相似文献
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Pornthep Sirimahachaiyakul Ravi F. Sood Lara A. Muffley Max Seaton Cheng-Ta Lin Liang Qiao Jeffrey S. Armaly Anne M. Hocking Nicole S. Gibran 《PloS one》2015,10(9)