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91.

Introduction

On May 26, 2009, the first confirmed case of Pandemic (H1N1) 2009 virus (pH1N1) infection in Hunter New England (HNE), New South Wales (NSW), Australia (population 866,000) was identified. We used local surveillance data to estimate pH1N1-associated disease burden during the first wave of pH1N1 circulation in HNE.

Methods

Surveillance was established during June 1-August 30, 2009, for: 1) laboratory detection of pH1N1 at HNE and NSW laboratories, 2) pH1N1 community influenza-like illness (ILI) using an internet survey of HNE residents, and 3) pH1N1-associated hospitalizations and deaths using respiratory illness International Classification of Diseases 10 codes at 35 HNE hospitals and mandatory reporting of confirmed pH1N1-associated hospitalizations and deaths to the public health service. The proportion of pH1N1 positive specimens was applied to estimates of ILI, hospitalizations, and deaths to estimate disease burden.

Results

Of 34,177 specimens tested at NSW laboratories, 4,094 (12%) were pH1N1 positive. Of 1,881 specimens from patients evaluated in emergency departments and/or hospitalized, 524 (26%) were pH1N1 positive. The estimated number of persons with pH1N1-associated ILI in the HNE region was 53,383 (range 37,828–70,597) suggesting a 6.2% attack rate (range 4.4–8.2%). An estimated 509 pH1N1-associated hospitalizations (range 388–630) occurred (reported: 184), and up to 10 pH1N1-associated deaths (range 8–13) occurred (reported: 5). The estimated case hospitalization ratio was 1% and case fatality ratio was 0.02%.

Discussion

The first wave of pH1N1 activity in HNE resulted in symptomatic infection in a small proportion of the population, and the number of HNE pH1N1-associated hospitalizations and deaths is likely higher than officially reported.  相似文献   
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Allelochemicals are secondary metabolites which are not edible and can be used as growth regulators and bio-herbicides. The goal of current study was to assess allelopathic ability of Lantana camara (Sage-plant) flowers against weeds viz. Avena fatua (Wild oat), Euphorbia helioscopia (Sun-spurge), Chenopodium album (Goosefoot), Phalaris minor (Canary-grass), and Rumex dentatus (Knotweed). Bioassay analysis of three methanolic fractions of the Combiflash from L. camara was performed at 50%, 75% and 100% concentration using germination percentage parameters, inhibition of plumule and radicle size. The fraction II of Combiflash strongly suppressed all weeds with negligible effect on T. aestivum. Gas chromatography-mass spectroscopy was conducted for the fraction, and isolated compounds were used to perform bioassays. From fraction II GC–MS detected four methyl esters of allelopathic fatty acid viz. Methyl oleate, methyl palmitate, methyl stearate and methyl linoleate. The evaluation of physiological effects of the bioassay revealed substantial suppression of chlorophyll, antioxidant enzymes (superoxide, dismutase peroxidase) and protein material in all weeds by methyl palmitate. Bioassay activity and study of physiological parameters revealed that the effective bio-herbicidal compound in Lantana camara flowers is methyl palmitate. This is the first time that methyl palmitate (a fatty acid methyl ester) has been related to herbicidal activity in L. camara flowers. It is proposed that field studies based on hormesis research and the mechanism of action of this compound be carried out.  相似文献   
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Feline immunodeficiency virus (FIV) is a lentivirus that causes immune suppression and neurological disease in cats. Among animal viruses, individual viral strains have been shown to be neurovirulent, but the role of viral strain specificity among lentiviruses and its relationship to systemic immune suppression in the development of neurological disease remains uncertain. To determine the extent to which different FIV strains caused neurological disease, FIV V1CSF and Petaluma were compared in ex vivo assays and in vivo. Both viruses infected and replicated in macrophage and mixed glial cell cultures at similar levels, but V1CSF induced significantly greater neuronal death than Petaluma in a neurotoxicity assay. V1CSF-infected animals showed significant neurodevelopmental delay compared to the Petaluma-infected and uninfected animals. Magnetic resonance spectroscopy studies of frontal cortex revealed significantly reduced N-acetyl aspartate/creatine ratios in the V1CSF group compared to the other groups. Cyclosporin A treatment of Petaluma-infected animals caused neurodevelopmental delay and reduced N-acetyl aspartate/creatine ratios in the brain. Reduced CD4+ and CD8+ cell counts were observed in the V1CSF-infected group compared to the uninfected and Petaluma-infected groups. These findings suggest that neurodevelopmental delay and neuronal injury is FIV strain specific but that systemic immune suppression is also an important determinant of FIV-induced neurovirulence.  相似文献   
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The aim of this study was to identify the effect of inclusion of defatted black soldier fly larvae (Def-BSFL) meal as a protein source on the performance and blood plasma constituents of broiler chickens. A total of 360-day-old chicks were assigned into four dietary groups, which included four different levels of Def-BSFL meal namely control (0% BSFL), T1(4% BSFL), T2 (8% BSFL) and T3 (12% BSFL) for six weeks experimental feeding period. At the end of the experiment, the blood samples of three birds from each treatment were collected to measure plasma constituents. Birds fed control and T1 diets demonstrated higher feed intake during the finisher stage compared with T2 and T3 diets. The heaviest weight for the 6-week feeding trial was recorded at T1 (1043.8 ± 65.9 g). Birds fed T1 (1.1 ± 0.0) and T3 (0.9 ± 0.1) diets displayed lower feed conversion ratio during the finisher stage than those fed control (1.7 ± 0.1) and T2 (1.8 ± 0.3) diets. Birds fed the control diet demonstrated the highest red blood cell with mean and standard deviation of 7.5 ± 0.34, whereas those fed the T2 diet showed the highest haemoglobin levels with mean and standard deviation of 15.8 ± 0.24. Birds fed T1, T2, and T3 diets exhibited a higher number (P < 0.05) of monocytes than those fed a control diet. There were no differences in white blood cell count across all the groups. In addition, birds fed the T2 diet showed higher (P < 0.05) blood urea nitrogen followed by the T3, control, and T1 diets. As a conclusion, the 4% Def-BSFL in the broiler chicken diet could be used to replace fish meal (FM) and soybean meal (SBM) without compromising bird performance and blood traits.  相似文献   
98.
Using human term placental mitochondrial preparations, optimal conversion of [3H]pregnenolone to [3H]progesterone was obtained at 30 min incubation and with a mitochondrial protein content of 2.5-3.5 mg/ml. Estradiol, estrone, progesterone and testosterone in a dose range of 0.03-8.66 mumol inhibited the in vitro conversion of [3H]pregnenolone to [3H]progesterone by placental homogenates. All four steroids inhibited the pregnenolone to progesterone conversion in a dose-dependent manner. The ID50 (dose required to inhibit conversion of pregnenolone to progesterone by 50%) was 0.04 mumol for estradiol, 0.13 mumol for testosterone, 0.3 mumol for progesterone and 1.0 mumol for estriol. Neither gonadotropin releasing hormone (50-1000 ng) nor human chorionic gonadotropin (5-500 IU) affected the placental basal conversion rate of pregnenolone to progesterone in vitro. Our findings indicate that steroid hormones such as estradiol, estrone, testosterone and progesterone can inhibit local placental progesterone biosynthesis through inhibition of the enzyme complex 5-ene-3 beta-hydroxysteroid dehydrogenase.  相似文献   
99.

Background

In 2009, a novel influenza virus (2009 pandemic influenza A (H1N1) virus (pH1N1)) caused significant disease in the United States. Most states, including Florida, experienced a large fall wave of disease from September through November, after which disease activity decreased substantially. We determined the prevalence of antibodies due to the pH1N1 virus in Florida after influenza activity had peaked and estimated the proportion of the population infected with pH1N1 virus during the pandemic.

Methods

During November-December 2009, we collected leftover serum from a blood bank, a pediatric children''s hospital and a pediatric outpatient clinic in Tampa Bay Florida. Serum was tested for pH1N1 virus antibodies using the hemagglutination-inhibition (HI) assay. HI titers ≥40 were considered seropositive. We adjusted seroprevalence results to account for previously established HI assay specificity and sensitivity and employed a simple statistical model to estimate the proportion of seropositivity due to pH1N1 virus infection and vaccination.

Results

During the study time period, the overall seroprevalence in Tampa Bay, Florida was 25%, increasing to 30% after adjusting for HI assay sensitivity and specificity. We estimated that 5.9% of the population had vaccine-induced seropositivity while 25% had seropositivity secondary to pH1N1 virus infection. The highest cumulative incidence of pH1N1 virus infection was among children aged 5–17 years (53%) and young adults aged 18–24 years (47%), while adults aged ≥50 years had the lowest cumulative incidence (11–13%) of pH1N1 virus infection.

Conclusions

After the peak of the fall wave of the pandemic, an estimated one quarter of the Tampa Bay population had been infected with the pH1N1 virus. Consistent with epidemiologic trends observed during the pandemic, the highest burdens of disease were among school-aged children and young adults.  相似文献   
100.
Probiotics and Antimicrobial Proteins - Probiotic, prebiotic, and synbiotic application have got considerable attention in aquaculture as a functional feed additive. This trial was considered to...  相似文献   
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