Epidemiological and clinical characteristics of the outbreak of 2009 pandemic influenza A (H1N1) at a middle school in Luoyang, China

OBJECTIVES

To describe the epidemiological and clinical characteristics of 2009 H1N1 influenza, particularly the incubation period and the duration of symptoms, and to assess the public health response to this outbreak.

STUDY DESIGN

A retrospective cohort study was conducted among all students and employees in a middle school by telephone survey and laboratory inspection.

METHODS

Nasopharyngeal specimens were collected and tested, and real-time reverse transcriptase polymerase chain reaction testing was performed to confirm the viral infection. The epidemiological and clinical characteristics were obtained through a telephone survey, and the incubation period and the duration of symptoms associated with 2009 H1N1 influenza were estimated by parametric distribution.

RESULTS

In total, 253 cases of influenza-like illness were found among students and employees, and 79 of these cases were confirmed as H1N1 infection through laboratory inspection. The response rate for the telephone survey was 93.48% for the students (2586/2768) and 85.87% for the employees (158/184). The average attack rate was 9.22% (253/2744). The main reported symptoms were fever (100%), cough (74.68%), sore throat (59.49%), headache (56.96%) and myalgia/arthralgia (51.90%). No complications were reported and no deaths occurred. The confirmed and suspected cases had no associated travel history or contact with a confirmed or probable case. The estimated median incubation period was 1.6 days [95% confidence interval (CI) 1.2-2.3]. The duration of symptoms was 3-11 days, and the median duration of symptoms was 7.5 days (95% CI 4.5-10.5).

CONCLUSIONS

The results suggest that the outbreak of 2009 H1N1 influenza in this middle school was widespread but not severe. The natural history of 2009 H1N1 influenza virus appears to be similar to that of previously circulating pandemic and interpandemic influenza viruses. The public health response indicates that school closure could have a substantial impact on the spread of 2009 H1N1 influenza.

Deuteron injector for Peking University Neutron Imaging Facility project

The deuteron injector developed for the PKUNIFTY (Peking University Neutron Imaging Facility) has been installed and commissioned at Peking University (PKU). The injector system must transfer 50 keV 50 mA of D(+) ion beam to the entrance of the 2 MeV radio frequency quadrupole (RFQ) with 10% duty factor (1 ms, 100 Hz). A compact 2.45 GHz permanent magnet electron cyclotron resonance (PMECR) ion source and a 1.36 m long low energy beam transport (LEBT) line using two solenoids was developed as the deuteron injector. A φ5 mm four-quadrant diaphragm was used to simulate the entrance of RFQ electrodes. The beam parameters are measured after this core with an emittance measurement unit (EMU) and a bending magnet for ion fraction analysis at the end of injector. During the commissioning, 77 mA of total deuteron beam was extracted from PMECR and 56 mA of pure D(+) beam that passed through the φ5 mm four-quadrant diaphragm was obtained at the position of RFQ entrance with the measured normalized rms emittance 0.12-0.16π mm mrad. Ion species analysis results show that the deuteron fraction is as high as 99.5%. All of the parameters satisfy PKUNIFTY's requirements. In this paper, we will describe the deuteron injector design and report the commissioning results as well as the initial operation.

Inhibition of sphingosine kinase 1 suppresses proliferation of glioma cells under hypoxia by attenuating activity of extracellular signal-regulated kinase

OBJECTIVES

Sphingosine kinase (SphK), which is regulated by hypoxia, catalyses phosphorylation of sphingosine to produce sphingosine-1-phosphate, which stimulates invasiveness of gliomas. However, whether SphK is involved in proliferation of glioma cells under hypoxic conditions is not clearly understood. In this study, we have investigated the role of SphK in of proliferation glioma cells under hypoxia.

MATERIALS AND METHODS

  Effects of small interfering RNA (siRNA) on SphKs, SKI (inhibitor of SphK) and U0126 (inhibitor of ERK) on proliferation of glioma cells under hypoxia were studied using CCK-8 assay and flow cytometry. Protein expression profiles were evaluated by Western blot analysis.

RESULTS

SKI suppressed proliferation of glioma cells under hypoxia. Similarly, downregulation of SphKs by siRNA inhibited glioma cell proliferation, and the cell cycle was arrested in G(2) /M phase when SphK1 was inhibited. In addition, inhibition of SphK1 attenuated phosphorylation of ERK in hypoxic conditions. Furthermore, U0126 markedly inhibited cell population growth and arrested cells in G(2) /M as effectively as SKI. However, silencing SphK2 induced cell cycle arrest in the S phase and it showed little effect on hypoxia-induced activation of ERK.

CONCLUSIONS

  SphK1 and SphK2 are involved in proliferation of glioma cells in hypoxic conditions through distinct signalling pathways. SphK1, but not SphK2, promotes cell population expansion in hypoxic conditions by activating ERK.

Mesoporous SnO2@carbon core-shell nanostructures with superior electrochemical performance for lithium ion batteries

SnO2@carbon nanostructure composites are prepared by a simple hydrothermal method. The composite exhibits unique structure, which consists of a mesoporous SnO2 core assembled of very small nanoparticles and a carbon shell with 10 nm thickness. The mesoporous SnO2@carbon core-shell nanostructures manifest superior electrochemical performance as an anode material for lithium ion batteries. The reversible specific capacity of the composite is about 908 mAh g(-1) for the first cycle and it can retain about 680 mAh g(-1) after 40 charge/discharge cycles at a current density of 0.3 C. Moreover, it shows excellent rate capability even at the high rate of 4.5 C. The enhanced performance was attributed to the mesoporous structure and a suitable carbon coating.

Novel ferromagnetic nanoparticle composited PACls and their coagulation characteristics

Effects of magnetic nanoparticles on inorganic coagulants and their coagulation performances were studied in the present work. The Fe(3)O(4)-SiO(2) core-shell particle (FSCSP) and superfine iron (SI), were compounded with polyaluminium chloride of basicity 2.0 (PACl2.0), providing magnetic PACl2.0s (MPACl2.0s). The physiochemical properties of ferromagnetic nanoparticles were investigated using transmission electron microscopy (TEM), the BET method and a zeta potentiometric analyzer. The Al species distributions of the MPACl2.0s and PACl2.0 were examined by liquid (27)Al NMR. Jar tests were employed to evaluate the coagulation performances. Floc properties were assessed by use of the electromotive microscope (EM) and small angle laser light scattering (SALLS). The results showed that modified layers of nanoparticles mitigated agglomeration. FSCSP had a larger specific area and pore volume than SI. The addition of ferromagnetic nanoparticles obviously increased the content of Al(un). MPACl2.0s performed better than PACl2.0 in turbidity removal and DOC removal when dosed less than 0.06 mmol/L as Al. Generally, PACl2.0 + FSCSP (50 mg/L) performed best. Large, loose and weak flocs were produced by MPACl2.0s, which were preferred for the magnetic powder recycling. A plausible structure, Al species-nanoparticles cluster, contributing to the unique properties of MPACl2.0 flocs, was proposed.

104 BIRTH OF FIRST BUFFALO (BUBALUS BUBALS) CALF FOLLOWING EMBRYO SPLITTING AND POLYMERASE CHAIN REACTION SEXING AT BLASTOCYST STAGE

Embryo-splitting technology provides an effective procedure for increasing the number of transferable embryos per donor, producing genetically identical offspring and facilitating embryo sexing. The ability to identify the sex of embryos before transfer will offer a reliable, economical and practical procedure for buffalo breeding. In this study, we have assessed the feasibility of production of offspring with controlled sex in buffalo by first comparing the effect of blastocyst quality on the viability of demi-embryos and then identifying the sex of a demi-embryo by multiplex-nested PCR before transfer into the recipient. In vitro-matured buffalo oocytes were fertilized by IVF and cultured to the blastocyst stage for 6 to 7 days as described by Lu et al. (2007 Anim. Reprod. Sci. 100, 192–196). These blastocysts were classified in terms of their developmental pattern and morphology on a scale of 1 to 3 grades as described by McEvoy et al. (1990 Theriogenology 33, 1245–1253). Blastocysts were split into 2 equal parts by a micromanipulation system. Viability of the resulting demi-embryos was confirmed by formation of a blastocoel cavity and definite inner cell mass after culture for 24 h. One of the zone-free demi-embryos derived from a grade-1 blastocyst was cultured in TCM 199 supplemented with 10% fetal bovine serum for another 2 h, then was transplanted to a spontaneous oestrous recipient. The other demi-embryo was used for sexing by multiplex-nested PCR (Fu et al. 2007 Theriogenology 68, 1211–1218). The results showed that grade-1 blastocysts yielded more viable demi-embryos than grade-2 and grade-3 blastocysts [P < 0.01; 73/92 (79.67%) vs 32/76 (47.05%) vs 26/94 (26.53%), respectively]. Transplantation of the presumed-Y demi-embryo derived from grade-1 blastocyst into a recipient resulted in the birth of a male buffalo calf. To the best of our knowledge, this is the first buffalo calf produced following embryo splitting and PCR sexing of the embryo at the blastocyst stage. Successful birth of the desired-sex offspring in the present study indicates the feasibility of using embryo splitting in combination with multiplex-nested PCR sexing to produce offspring of controlled sex in swamp buffalo. However, the quality of embryos before splitting was an important factor governing the in vitro development of viable demi-embryos. This study was supported by the Guangxi Science and Technology R&D Program (0626001-3-1, 0815008-2-4).

PD08-05: Stat3 Signaling in Human Breast Cancer Stem Cells

Recent data suggest the existence of a unique subset of breast cancer cells capable of initiating tumor growth and giving rise to all other cells characteristic of a given tumor. These cells have been termed “cancer stem cells” or “tumor-initiating cells”. Breast cancer stem cells appear to be resistant to chemo- and radiotherapies and may be responsible for recurrence and metastasis in breast cancer patients. Identifying the cellular signaling pathways responsible for breast cancer stem cell maintenance and self-renewal represents a critical hurdle for developing effective therapeutics. The Stat3 pathway is a critical regulator of the function of normal stem cells, and shows altered expression in human breast cancers [4]. Moreover, IL-6, the Stat3 signaling agonist, is required for breast cancer stem cell function in human breast cancer cell lines. All these suggest an important role of Stat3 signaling in breast cancer stem cells. However, due to lack of method for pathway-activity-based live cell separation, whether Stat3 functions in the cancer stem cells themselves or whether it may function in surrounding niche cells remain unknown. We have constructed a lentiviral fluorescent reporter for Stat3 signaling which contains four copies of M67 Stat3 binding sites upstream of enhanced Green Fluorescent Protein. This reporter system enables FACS-sorting of cells with active Stat3 signaling and in vivo/in situ localization of Stat3 responsive cells. In addition, C188-9, the first Stat3 specific competitive inhibitor, has been developed in our collaborator's lab, which provides us an advanced tool in studying Stat3 function.

We hypothesize that Stat3 signaling is preferentially active in stemlike subpopulation and depend on non-stem cancer cells to maintain its activation. Three aims to test this hypothesis include: 1. To test whether cancer cells with activated Stat3 signaling are enriched for breast cancer stem cells or whether they may serve as niche cells. 2. To test whether small molecule antagonists of Stat3 signaling can inhibit cancer stem cell function. 3. To identify novel targets of Stat3 signaling that may serve as indicators of responsiveness to Stat3 antagonist or predict treatment response.

So far, our GFP reporters for Stat3 signaling effectively report Stat3 activity in both patient xenografts and human breast cancer cell lines in vivo and in vitro, which enables effective separation of Stat3+/Stat3- cells for functional Study. MDA231 and SUM159 tumors with reporters have been established. Tumor cells will be sorted according to Stat3 activity and perform limiting dilution and MSFE assays. Tumors with reporters will also be treated by C188-9, Chemo, or in combination to study synergistic effect of Stat3 inhibitors on tumor growth. Preliminary data based on inhibitor and limiting dilution studies suggested that Stat3 signaling is required for stem cell function. However, neither Stat3+ nor Stat3- cells are self-sufficient in performing these functions, indicating communications between subpopulations.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr PD08-05.

Antioxidant micronutrients improve intrinsic and UV-induced apoptosis of human lymphocytes particularly in elderly people

OBJECTIVE

Aging and oxidative stress may lead to enhanced cellular damage and programmed cell death. To study the association of intrinsic apoptosis with age and the effect of antioxidant supplementation on intrinsic and UV-induced apoptosis in children, young and elderly people.

METHODS

The study was a 2 months, double-blind, randomized trial. Three age groups were studied: children, young adults and elderly people. A total of 274 healthy subjects were allocated to a group supplemented with moderate amounts of retinol, β-carotene, α-tocopherol, ascorbic acid and selenium or placebo. Plasma oxidative stress parameters were detected and apoptosis of lymphocytes was evaluated with TUNEL staining.

RESULTS

At baseline, percentages of intrinsic apoptosis were 13.8% and 11.1% in elderly and young people, respectively, both significantly higher than children (6.3%). A decrease of 1.7% and 2.3% in intrinsic apoptosis of lymphocytes was found in the supplemented groups of young and elderly people compared with their control groups (all p values <0.001), but no significant decrease in children. Moreover, percentages UV-induced apoptosis significantly decreased by 1.4%, 1.9% and 3.1% in children, young and elderly people, respectively, compared with control groups after the trial. There were considerable increments in concentrations of plasma β-carotene, retinol, tocopherol, ascorbic acid and selenium in all three treated groups after the supplementation.

CONCLUSIONS

Young and elderly people have a higher intrinsic apoptosis than children, which was improved by antioxidant supplementation. UV-induced damage was attenuated by the supplementation in all three age groups.

A naturally occurring nanomaterial from the Sundew (Drosera) for tissue engineering

In recent years advances have been made in the design of novel materials for tissue engineering through the use of polysaccharides. This study evaluated the ability of a naturally secreted polysaccharide adhesive from the Sundew (Drosera capensis) as a support for cell growth. The Sundew adhesive has several advantages including its high elasticity and antibiotic nature. By coating glass cover slips with the Sundew adhesive, a network of nanofibers was generated that was capable of promoting attachment and differentiation of a model neuronal cell line, PC-12. We also demonstrated the potential of this material for repairing bone and soft tissue injuries, by testing attachment of osteoblasts and endothelial cells. Finally, it was determined that the Sundew biomaterial was stable through testing by atomic force microscopy and prolonged cell growth. This work has proven the capabilities of using a nanomaterial derived from the Sundew adhesive for the purpose of tissue engineering.

Interleukin-10 polymorphisms and tuberculosis susceptibility: a meta-analysis

BACKGROUND

A large number of studies have shown that polymorphisms in the interleukin 10 (IL-10) gene are implicated in susceptibility to tuberculosis (TB). However, the results are inconsistent and inconclusive.

OBJECTIVE

A meta-analysis was performed to analyse the association between polymorphisms in the IL-10 gene and TB susceptibility.

RESULTS

A total of 18 studies that referred to three polymorphisms (-1082G/A, -819C/T and -592A/C) were identified. No association was found between these three polymorphisms and TB risk in combined analyses: -1082G/A (AA+AG vs. GG): OR 0.87, 95%CI 0.66-1.14, P = 0.30; -819C/T (TT+TC vs. CC): OR 1.02, 95%CI 0.92-1.14, <e1>P</e> = 0.66; -592A/C (CC+CA vs. AA): OR 0.99, 95%CI 0.88-1.11, P = 0.82. However, in the subgroup analysis by ethnicity, European subjects with the -1082(AA+GG) genotypes have a decreased risk of TB: OR 0.55, 95%CI 0.35-0.88, P = 0.01.

CONCLUSION

This meta-analysis suggests that the -1082G/A polymorphism of the IL-10 gene could be a risk factor for TB in Europeans. Further studies with larger populations are required to assess the association between IL-10 polymorphisms and TB susceptibility.

Secreted glyceraldehyde-3-phosphate dehydrogenase as a broad spectrum vaccine candidate against microbial infection in aquaculture

AIMS

Subcellullar localizations and cross-immunities of GAPDHs from six common pathogenic bacteria in aquaculture were investigated.

METHODS AND RESULTS

Subcellullar localizations of GAPDHs of Edwardsiella tarda EIB202, Edwardsiella ictaluri ATCC33202, Aeromonas hydrophila LSA34, Vibrio anguillarum MVM425, Vibrio alginolyticus EPGS020401 and Vibrio harveyi VIB647 were analysed with Western blotting, indirect immunofluorescence and flow cytometry examinations. Immunoprotections of different recombinant GAPDHs against these pathogens were investigated with zebrafish model. Western blotting of subcellular extractions showed that all GAPDHs were secreted into extracellular medium and periplasmic space. In addition, GAPDHs were demonstrated to distribute in the outer membranes except MVM425 and VIB647. And, GAPDHs were confirmed to be present on the surface of these bacteria with indirect immunofluorescence and flow cytometry examinations. The remarkable cross-protective immunities of these recombinant GAPDHs were induced in zebrafish, and the relative protective survivals were almost over 60%.

CONCLUSIONS

Localizations of GAPDHs from these pathogenic bacteria were similar to many other causative agents. And, GAPDHs could be important protective antigens and give remarkable cross-immunity against different pathogens.

SIGNIFICANCE AND IMPACT OF THE STUDY

Recombinant GAPDH could be designed as a broad spectrum vaccine candidate against multiple microbial infections in aquaculture.

Associations of miRNA polymorphisms and female physiological characteristics with breast cancer risk in Chinese population

mircoRNAs (miRNAs) play important roles on regulation of gene expressions. Aberrant expression of miRNAs was involved in various biological and pathological processes, including tumorigenesis of breast cancer. Single-nucleotide polymorphisms (SNPs) were implicated in altered expression or biological functions of mature miRNAs. To explore the relevance of miRNA polymorphisms and female physiological characteristics to breast cancer risk, SNPs located within hsa-miR-605 (rs2043556), hsa-miR-149 (rs2292832), hsa-miR-27a (rs895819), hsa-miR-196a-2 (rs11614913) and hsa-miR-618 (rs2682818) were selected, and their associations with breast cancer risk were analysed. In addition, associations between physiological characteristics-related factors and breast cancer risk were estimated too. We found that the ones with menarche age less than 16 years had increased breast cancer risk (OR = 2.10, 95% CI: 1.23-3.60). Marginally significant association between rs11614913 CT/CC genotypes and reduced breast cancer risk was observed (OR = 0.65, 95% CI: 0.40-1.06), while no significance was detected about the other miRNA polymorphisms. We concluded that menarche at less than 16 years old increased breast cancer risk, while the genetic variants in miR-196-a-2 might decrease the risk.

Low glucose sensitivity and polymodal chemosensing in neonatal rat adrenomedullary chromaffin cells

Glucose is the primary metabolic fuel in mammalian fetuses, yet mammals are incapable of endogenous glucose production until several hours after birth. Thus, when the maternal supply of glucose ceases at birth there is a transient hypoglycemia that elicits a counterregulatory surge in circulating catecholamines. Because the innervation of adrenomedullary chromaffin cells (AMCs) is immature at birth, we hypothesized that neonatal AMCs act as direct glucosensors, a property that could complement their previously established roles as hypoxia and acid hypercapnia sensors. During perforated-patch, whole cell recordings, low glucose depolarized and/or excited a subpopulation of neonatal AMCs; in addition, aglycemia (0 mM glucose) caused inhibition of outward K+ current, blunted by the simultaneous activation of glibenclamide-sensitive KATP channels. Some cells were excited by each of the three metabolic stimuli, i.e., aglycemia, hypoxia (Po2 ∼30 mmHg), and isohydric hypercapnia (10% CO2; pH = 7.4). Using carbon fiber amperometry, aglycemia and hypoglycemia (3 mM glucose) induced robust catecholamine secretion that was sensitive to nickel (50 μM and 2 mM) and the L-type Ca2+ channel blocker nifedipine (10 μM), suggesting involvement of both T-type and L-type voltage-gated Ca2+ channels. Fura-2 measurements of intracellular Ca2+ ([Ca2+] i) revealed that ∼42% of neonatal AMCs responded to aglycemia with a significant rise in [Ca2+] i. Approximately 40% of these cells responded to hypoxia, whereas ∼25% cells responded to both aglycemia and hypoxia. These data suggest that together with hypoxia and acid hypercapnia, low glucose is another important metabolic stimulus that contributes to the vital asphyxia-induced catecholamine surge from AMCs at birth.

Deficiency in TLR2 but not in TLR4 impairs dendritic cells derived IL-10 responses to schistosome antigens

The purpose of this study was to observe the diverse functions of Toll-like receptors (TLRs) in responses to specific schistosome antigens. Bone marrow-derived dendritic cells (BMDCs) from TLR2-deficient (TLR2(-/-)) or TLR4-deficient (TLR4(-/-)) mice were activated with soluble schistosomule antigen (SSA) or soluble egg antigen (SEA). TLR2 mRNA expression was significantly increased in B6 BMDCs following SEA stimulation. TLR2-deficient BMDCs showed enhanced MHCII expression following SSA and SEA stimulation. TLR2-deficient but not TLR4-deficient BMDC failed to produce IL-12p70 and IL-10 in response to schistosome antigens. TLR2-deficient BMDCs induced a stronger CD4(+) T cell proliferative response. IL-4 and IL-10 expression was inhibited in CD4(+) T cells primed with TLR2-deficient BMDCs, while enhanced in TLR4-deficient BMDCs-primed CD4(+) T cells. These results suggest that TLR2 is essential for the establishment of the DC production of IL-12p70 and IL-10.