[Infection of human normal lung epithelial cells by Hantaan virus (HTNV) and its impact on innate immunity and metabolism].

Objective To confirm that Hantaan virus (HTNV) can infect BEAS-2B human normal lung epithelial cells and examine the host immune response and metabolic changes induced by HTNV infection by transcriptomic analysis. Methods Western blotting, quantitative real-time PCR and immunofluorescence assay were used to assess the viral load in BEAS-2B cells, and RNA sequencing was employed for transcriptomic analysis. Results Following the infection of BEAS-2B cells with HTNV, there was an increase in the expression of HTNV nucleocapsid protein (NP) and small segment (S) over time. A transcriptomic analysis of these infected cells at 48-hour mark identified 328 genes that were differentially expressed. GO and KEGG enrichment analysis revealed that these differences were primarily associated with interferon response and innate immune pattern recognition receptor pathways. Protein-protein interaction network analysis identified several genes related to innate immune responses, including four genes encoding disintegrin and metalloproteinase with thrombospondin motifs. Metabolic pathway analysis showed three genes related to terpenoid backbone biosynthesis, two genes related to glycolysis/gluconeogenesis and two genes related to steroid hormone biosynthesis. Subcellular localization analysis indicated that many of the differentially expressed genes were located in mitochondria. Conclusion HTNV is capable of effectively infecting BEAS-2B cells, making them a suitable in vitro model for studying HTNV infection in human lung epithelial. By utilizing bioinformatics methods to screen for differentially expressed genes and metabolic pathways associated with HTNV infection, researchers can establish a theoretical foundation for investigating the molecular mechanisms underling HTNV infection.

T-cell immunoglobulin and mucin 1 (TIM-1) mediates infection of Hantaan virus in Jurkat T cells.

Hantaan virus (HTNV) is a major public health concern due to its ability to cause hemorrhagic fever with renal syndrome (HFRS) in Eurasia. Symptoms of HFRS include fever, hemorrhage, immune dysfunction and renal impairment, and severe cases can be fatal. T cell-mediated adaptive immune responses play a pivotal role in countering HTNV infection. However, our understanding of HTNV and T cell interactions in the disease progression is limited. In this study, we found that human CD4+ T cells can be directly infected with HTNV, thereby facilitating viral replication and production. Additionally, T-cell immunoglobulin and mucin 1 (TIM-1) participated in the process of HTNV infection of Jurkat T cells, and further observed that HTNV enters Jurkat T cells via the clathrin-dependent endocytosis pathway. These findings not only affirm the susceptibility of human CD4+ T lymphocytes to HTNV but also shed light on the viral tropism. Our research elucidates a mode of the interaction between the virus infection process and the immune system. Critically, this study provides new insights into the pathogenesis of HTNV and the implications for antiviral research.

NLRX1: a key regulator in mitochondrial respiration and colorectal cancer progression.

Colorectal cancer (CRC) is a prevalent and aggressive malignancy with high mortality rates and significant risks to human well-being. Population-wide screening for tumor suppressor genes and oncogenes shows promise for reducing the incidence and fatality of CRC. Recent studies have suggested that NLRX1, an innate immunity suppressor, may play a role in regulating chronic inflammation and tumorigenesis. However, further investigation is needed to understand the specific role of NLRX1 in CRC. To evaluate the impact of NLRX1 on migration, invasion, and metastasis, two human colon cancer cell lines were studied in vitro. Additionally, a knockout mouse tumor-bearing model was used to validate the inhibitory effect of NLRX1 on tumor emergence and progression. The Seahorse XF96 technology was employed to assess mitochondrial function and glycolysis in colorectal cancer cells overexpressing NLRX1. Moreover, public databases were consulted to analyze gene and protein expression levels of NLRX1. Finally, the results were validated using a series of CRC patient samples. Our findings demonstrate that downregulation of NLRX1 enhances proliferation, colony formation, and tumor-forming capacity in HCT116 and LoVo cells. Conversely, overexpression of NLRX1 negatively impacts basal respiration and mitochondrial ATP-linked respiration in both cell lines, resulting in a notable decrease in maximal respiration during the standard mitochondrial stress test. Furthermore, analysis of data from the TCGA database reveals a significant reduction in NLRX1 expression in colon and rectal cancer tissues compared to normal tissues. This result was validated using clinical samples, where immunohistochemistry staining and western blotting demonstrated a notable reduction in NLRX1 protein levels in CRC compared to adjacent normal tissues. The decreased expression of NLRX1 may serve as a significant prognostic indicator and diagnostic biomarker for CRC patients.

A stable rhombohedral phase in ferroelectric Hf(Zr)1+xO2 capacitor with ultralow coercive field.

Hafnium oxide-based ferroelectric materials are promising candidates for next-generation nanoscale devices because of their ability to integrate into silicon electronics. However, the intrinsic high coercive field of the fluorite-structure oxide ferroelectric devices leads to incompatible operating voltage and limited endurance performance. We discovered a complementary metal-oxide semiconductor (CMOS)-compatible rhombohedral ferroelectric Hf(Zr)1+xO2 material rich in hafnium-zirconium [Hf(Zr)]. X-ray diffraction combined with scanning transmission electron microscopy reveals that the excess Hf(Zr) atoms intercalate within the hollow sites. We found that the intercalated atoms expand the lattice and increase the in-plane and out-of-plane stresses, which stabilize both the rhombohedral phase (r-phase) and its ferroelectric properties. Our ferroelectric devices, which are based on the r-phase Hf(Zr)1+xO2, exhibit an ultralow coercive field (~0.65 megavolts per centimeter). Moreover, we achieved a high endurance of more than 1012 cycles at saturation polarization. This material discovery may help to realize low-cost and long-life memory chips.

Investigation of a subunit protein vaccine for HFRS based on a consensus sequence between envelope glycoproteins of HTNV and SEOV.

Due to the global resurgence of hemorrhagic fever with renal syndrome (HFRS), more attention is being focused on this dangerous illness. In China and Korea, the only vaccines available are the virus-inactivated vaccine against Hantaan virus (HTNV) or Seoul virus (SEOV), but their efficacy and safety are inadequate. Therefore, it is important to develop new vaccines that are safer and more efficient to neutralize and regulate areas with a high prevalence of HFRS. We employed bioinformatics methods to design a recombinant protein vaccine based on conserved regions of protein consensus sequences in HTNV and SEOV membranes. The S2 Drosophila expression system was utilized to enhance protein expression, solubility and immunogenicity. After the Gn and Gc proteins of HTNV and SEOV were successfully expressed, mice were immunized, and the humoral immunity, cellular immunity, and in vivo protection of the HFRS universal subunit vaccine were systematically evaluated in mouse models. These results indicated that the HFRS subunit vaccine generated elevated levels of binding and neutralizing antibodies, particularly IgG1, compared to that of the traditional inactivated HFRS vaccine. Additionally, the spleen cells of immunized mice secreted IFN-r and IL-4 cytokines effectively. Moreover, the HTNV-Gc protein vaccine successfully protected suckling mice from HTNV infection and stimulated GC responses. In this research, a new scientific approach is investigated to develop a universal HFRS subunit protein vaccine that is capable of producing effective humoral and cellular immunity in mice. The results suggest that this vaccine could be a promising candidate for preventing HFRS in humans.

Improved Endurance of Ferroelectric Hf0.5Zr0.5O2 Using Laminated-Structure Interlayer.

In this article, the endurance characteristic of the TiN/HZO/TiN capacitor was improved by the laminated structure of a ferroelectric Hf0.5Zr0.5O2 thin film. Altering the HZO deposition ratio, the laminated-structure interlayer was formed in the middle of the HZO film. Although small remanent polarization reduction was observed in the capacitor with a laminated structure, the endurance characteristic was improved by two orders of magnitude (from 106 to 108 cycles). Moreover, the leakage current of the TiN/HZO/TiN capacitor with the laminated-structure interlayer was reduced by one order of magnitude. The reliability enhancement was proved by the Time-Dependent Dielectric Breakdown (TDDB) test, and the optimization results were attributed to the migration inhibition and nonuniform distribution of oxygen vacancies. Without additional materials and a complicated process, the laminated-structure method provides a feasible strategy for improving HZO device reliability.

Underpinning Chinese international students' stress and anxiety during the first wave of COVID-19 outbreak: The moderating role of wisdom.

During the first wave of the COVID-19 outbreak, the Chinese diaspora, especially Chinese international students, were subjected to greater stress than others, because they were under pressure from both fear of infection and coping with acculturation (e.g., discrimination). Consequently, more research is needed to understand the anxiety induced by COVID-19 stresses on this specific cultural group. The main purpose of this study is to investigate the relationship between COVID-19 stress and individuals' anxiety, and the moderating roles of Acceptance, Reframing, and Striving (ARS) coping, the family support coping strategy, and wise reasoning. To test our predictions, we collected data from 224 Chinese international students (CIS). Results indicated a strong and positive relationship between pandemic stress and anxiety. Surprisingly, both ARS and family support coping did not moderate the association between COVID-19 stress and anxiety. Instead, wise reasoning as a potential reflective coping strategy interacted with COVID-19 stress to predict anxiety. Specifically, wise reasoning predicted more anxiety when individuals perceived a low-level of COVID-19 stress, however, such a relationship disappeared when individuals perceived a high-level of COVID-19 stress. These findings about wise-reasoning extends our understanding of wisdom and how it plays a role in the context of COVID-19.

Surges of hospital-based rhinovirus infection during the 2020 coronavirus disease-19 (COVID-19) pandemic in Beijing, China.

BACKGROUND: A series of public health preventive measures has been widely implemented in Beijing to control the coronavirus disease-19 (COVID-19) pandemic since January 2020. An evaluation of the effects of these preventive measures on the spread of other respiratory viruses is necessary. METHODS: Respiratory specimens collected from children with acute respiratory infections were tested by NxTAG™ respiratory pathogen panel assays during January 2017 and December 2020. Specimens characterized as rhinoviruses (RVs) were sequenced to identify the RV species and types. Then, the epidemiology results of respiratory pathogens in 2020 were compared with those from 2017 to 2019 using SPSS statistics 22.0. RESULTS: The positive rates of adenovirus (ADV), influenza virus (flu), RVs, and respiratory syncytial virus (RSV) dropped abruptly by 86.31%, 94.67%, 94.59%, and 92.17%, respectively, from February to May 2020, compared with the average level in the same period during 2017-2019. Positive rates of RVs then steeply increased from June 2020 (13.77%), to an apex (37.25%) in August 2020, significantly higher than the average rates (22.51%) in August 2017-2019 (P = 0.005). The increase, especially in group ≥ 3 years, was accompanied by the reopening of schools and kindergartens after the 23rd and 24th week of 2020 in Beijing. CONCLUSIONS: Whereas the abrupt drop in viral pathogen positive rates from February to May 2020 revealed the remarkable effects of the COVID-19 preventive measures, the sharp increase in positive rates of RVs from the 23rd week of 2020 might be explained by the reopening of schools and kindergartens in Beijing.

Tracing the emerging genotypes of human respiratory syncytial virus in Beijing by evolution analysis of the attachment glycoprotein (G) gene.

BACKGROUND: Emerging human respiratory syncytial virus (HRSV) genotypes, such as ON1 and BA9, are becoming the dominant genotypes prevailing worldwide. Objective To trace the emerging HRSV genotypes in Beijing. METHODS: HRSV-positive specimens as determined by direct immunofluorescence, collected from children diagnosed with bronchiolitis from July 2006 to June 2016, were typed by real-time PCR, then genotyped by phylogenetic analyses of the full attachment glycoprotein (G) gene. A Bayesian skyline plot was constructed to analyze the population dynamics for identified HRSV strains, and selective pressure was analyzed. RESULTS: The previous dominant HRSV A genotype, NA1, was replaced by ON1 in 2014. BA9 was the dominant HRSV B genotype for the duration of the study. The time to the most recent common ancestor (tMRCA) for HRSV A is since the 1943-1944 season; for the genotypes NA1 and ON1, since the 1999-2000 season and 2010-2011 season, respectively. The tMRCA for HRSV B is since the 1956-1957 season; for the genotypes BA and BA9, from the 1998-1999 season and 2005-2006 season, respectively. The mean evolutionary rate of HRSV A (3.65 × 10-3) was faster than those of HRSV B (3.11 × 10-3), and the genotypes NA1 (2.01 × 10-3) and ON1 (1.66 × 10-3). The estimated effective population size (EPS) infected by HRSV A changed significantly from 2012 to 2013, which is consistent with the detection of ON1. Most positive selection sites were concentrated in the second highly variable region (HVR2) of the G gene. CONCLUSIONS: Over the 10-year period from 2006 to 2016, the dominant genotypes in Beijing were NA1, ON1, and BA9. The HRSV strains in Beijing may have their own unique phylogenetic characteristics.

Mal-Lys: prediction of lysine malonylation sites in proteins integrated sequence-based features with mRMR feature selection.

Lysine malonylation is an important post-translational modification (PTM) in proteins, and has been characterized to be associated with diseases. However, identifying malonyllysine sites still remains to be a great challenge due to the labor-intensive and time-consuming experiments. In view of this situation, the establishment of a useful computational method and the development of an efficient predictor are highly desired. In this study, a predictor Mal-Lys which incorporated residue sequence order information, position-specific amino acid propensity and physicochemical properties was proposed. A feature selection method of minimum Redundancy Maximum Relevance (mRMR) was used to select optimal ones from the whole features. With the leave-one-out validation, the value of the area under the curve (AUC) was calculated as 0.8143, whereas 6-, 8- and 10-fold cross-validations had similar AUC values which showed the robustness of the predictor Mal-Lys. The predictor also showed satisfying performance in the experimental data from the UniProt database. Meanwhile, a user-friendly web-server for Mal-Lys is accessible at http://app.aporc.org/Mal-Lys/.

Association of Different Human Rhinovirus Species with Asthma in Children: A Preliminary Study.

BACKGROUND: Human rhinoviruses (HRVs) are divided into three genetic species: HRV-A, HRV-B, and HRV-C. The association of different HRV species with asthma in children in China has not yet been evaluated. This preliminary study aimed to assess the associations between different HRV species, particularly HRV-C, and asthma in young children in China. METHODS: A total of 702 nasopharyngeal aspirates were obtained from 155 children with asthma (asthma group), 461 children with acute respiratory infection (ARI) without asthma (nonasthma ARI group), and 86 children from the control group. Semi-nested polymerase chain reaction (PCR) was used to detect HRVs, and PCR products were sequenced for species identification. Epidemiological characteristics of HRV-positive cases were analyzed. RESULTS: HRVs were the most common pathogen (15.4%; 108/702) in the patients in this study. The prevalence of HRV was significantly different (F = 20.633, P = 0.000) between the asthma (25.8%) and nonasthma ARI groups (11.1%). Phylogenetic analysis indicated that in the 108 cases positive for HRVs, 41 were identified as HRV-A, 8 as HRV-B, and 56 as HRV-C. Comparing the asthma with the nonasthma ARI group, Spearman's rank correlation analysis revealed an association between HRV-A (P < 0.05) and C (P < 0.01) and asthma, confirmed by regression analysis, with odds ratios of 2.2 (HRV-A) and 4.2 (HRV-C). CONCLUSIONS: Our data revealed a high prevalence of HRVs in children in China, regardless of clinical status. HRV-C was the dominant species and may be one of the key factors in the association of HRVs with asthma.

Prediction of sumoylation sites in proteins using linear discriminant analysis.

Sumoylation is a multifunctional post-translation modification (PTM) in proteins by the small ubiquitin-related modifiers (SUMOs), which have relations to ubiquitin in molecular structure. Sumoylation has been found to be involved in some cellular processes. It is very significant to identify the exact sumoylation sites in proteins for not only basic researches but also drug developments. Comparing with time exhausting experiment methods, it is highly desired to develop computational methods for prediction of sumoylation sites as a complement to experiment in the post-genomic age. In this work, three feature constructions (AAIndex, position-specific amino acid propensity and modification of composition of k-space amino acid pairs) and five different combinations of them were used to construct features. At last, 178 features were selected as the optimal features according to the Mathew's correlation coefficient values in 10-fold cross validation based on linear discriminant analysis. In 10-fold cross-validation on the benchmark dataset, the accuracy and Mathew's correlation coefficient were 86.92% and 0.6845. Comparing with those existing predictors, SUMO_LDA showed its better performance.

Parainfluenza Virus Types 1, 2, and 3 in Pediatric Patients with Acute Respiratory Infections in Beijing During 2004 to 2012.

BACKGROUND: Although human parainfluenza virus (HPIV) has been determined as an important viral cause of acute respiratory infections (ARIs) in infants and young children, data on long-term investigation are still lacking to disclose the infection pattern of HPIV in China. METHODS: Nasopharyngeal aspirates were collected from 25,773 hospitalized pediatric patients with ARIs from January 2004 through December 2012 for respiratory virus screen by direct immuno-fluorescence assay. RESULTS: Out of these specimens, 1675 (6.50%, 1675/25,773) showed HPIV positive, including 261 (1.01%, 261/25,773) for HPIV1, 28 (0.11%, 28/25,773) for HPIV2, and 1388 (5.39%, 1388/25,773) for HPIV3, 2 of the samples were positive for both HPIV1 and HPIV3, and 36 were co-detected with other viruses. The positive rates of HPIVs were higher in those younger than 3 years old. HPIV3 was detected from all age groups, predominantly from patients under 3 years of age, and the highest frequency was found in those 6 months to 1-year old (352/4077, 8.63%). HPIV3 was the dominant type in each of the years detected between May and July. HPIV1 showed a peak in every odd year, mainly in August or September. HPIV was detected most frequently from patients with upper respiratory infection (12.49%, 157/1257), followed by bronchitis (11.13%, 176/2479), asthma (9.31%, 43/462), bronchiolitis (5.91%, 150/2536), pneumonia (6.06%, 1034/17,068), and those with underlying diseases (1.0%, 15/1506). HPIV3 is the dominant type in these six disease groups referred above, especially in the asthma group. CONCLUSIONS: HPIV is one of the important viral causes of ARIs in infants and young children in Beijing based on the data from the hospitalized children covering a 9-year term. HPIV3 is the predominant type in all these years and in most of the disease groups. HPIVs with different types show different seasonality.

iSuc-PseAAC: predicting lysine succinylation in proteins by incorporating peptide position-specific propensity.

Lysine succinylation in protein is one type of post-translational modifications (PTMs). Succinylation is associated with some diseases and succinylated sites data just has been found in recent years in experiments. It is highly desired to develop computational methods to identify the candidate proteins and their sites. In view of this, a new predictor called iSuc-PseAAC was proposed by incorporating the peptide position-specific propensity into the general form of pseudo amino acid composition. The accuracy is 79.94%, sensitivity 51.07%, specificity 89.42% and MCC 0.431 in leave-one-out cross validation with support vector machine algorithm. It demonstrated by rigorous leave-one-out on stringent benchmark dataset that the new predictor is quite promising and may become a useful high throughput tool in this area. Meanwhile a user-friendly web-server for iSuc-PseAAC is accessible at http://app.aporc.org/iSuc-PseAAC/. Users can easily obtain their desired results without the need to understand the complicated mathematical equations presented in this paper just for its integrity.

Phogly-PseAAC: Prediction of lysine phosphoglycerylation in proteins incorporating with position-specific propensity.

Large-scale characterization of post-translational modifications (PTMs), such as posphorylation, acetylation and ubiquitination, has highlighted their importance in the regulation of a myriad of signaling events. However, as another type of PTMs-lysine phosphoglycerylation, the data of phosphoglycerylated sites has just been manually experimented in recent years. Given an uncharacterized protein sequence that contains many lysine residues, which one of them can be phosphoglycerylated and which one not? This is a challenging problem. In view of this, establishing a useful computational method and developing an efficient predictor are highly desired. Here a new predictor named Phogly-PseAAC was developed which incorporated with the position specific amino acid propensity. The feature importance through F-score value has also been ranked. The predictor with the best feature set obtained the accuracy 75.10%, sensitivity 68.87%, specificity 75.57% and MCC 0.2538 in LOO test cross validation with center nearest neighbor algorithm. Meanwhile, a web-server for Phogly-PseAAC is accessible at http://app.aporc.org/Phogly-PseAAC/. For the convenience of most experimental scientists, we have further provided a brief instruction for the web-server, by which users can easily get their desired results without the need to follow the complicated mathematics presented in this paper. It is anticipated that Phogly-PseAAC may become a useful high throughput tool for identifying the lysine phosphoglycerylation sites.

Characteristics of the mosaic genome of a human parechovirus type 1 strain isolated from an infant with pneumonia in China.

Human parechoviruses (HPeVs) belong to the Parechovirus genus of the large and growing family of Picornaviridae with a non-enveloped, single-stranded and positive-sense RNA. An HPeV strain was isolated from the nasopharyngeal aspirate specimen of a 2 months old infant hospitalized with pneumonia in Beijing, China and nominated as BJ-37359 followed the code of the specimen. Strain BJ-37359 was identified as HPeV1 by whole genome sequencing. The full genome of strain BJ-37359 consisted of 7336 nucleotides (nt), excluding a poly (A) tail and contained an ORF of 6537 nt flanked by 5'UTR of 709 nt and 3'UTR of 90 nt. Phylogenetic analyses revealed that strain BJ-37359 were clustered together with HPeV1 strains in the structural capsid protein region, while uncoupling in the non-structural gene regions. Analyses with Simplot and Bootscan indicated that multiple recombination events occurred in the non-structural region and VP0 region of strain BJ-37359 with other HPeV1, and other types might have contributed to the recombination, especially HPeV6 and HPeV7 strains. Recombination analyses indicated that strain BJ-37359 may have a mosaic genome with new genomic recombination breakpoints.

[Human parechovirus associated sepsis and central nervous system infections in hospitalized children].

OBJECTIVE: Human parechovirus (HPeV) is a single-stranded, positive sense RNA virus in the Parechovirus genus within the large family of Picornaviridae. As a possible new pathogen of neonatal sepsis, meningoencephalitis and other infections in young children, HPeV gets more and more attention. This study aimed to better understand the association of HPeV with central nervous system (CNS) infectious diseases and sepsis among hospitalized children in Beijing. METHOD: A total of 577 cerebrospinal fluid (CSF) samples were retrospectively collected from 557 children suspected of CNS infections in 2012. Three hundred and fifty-one of them were male and 206 were female. HPeV was screened by reverse transcription-nested PCR (RT-nPCR) with the universal primers which target the highly conserved 5'UTR. The positive samples were genotyped by amplifying and sequencing for the VP3/VP1 junction region. The sequences were compared with the HPeV sequences from GenBank and performed phylogenetic analysis.Some samples other than CSF from HPeV positive children, including serum, nasopharyngeal aspirate and stool, were collected and carried out screening for HPeV. RESULT: With the RT-nPCR by universal primers, HPeVs were detected in 18 out of 577 CSF samples obtained from 18 children with a positive rate of 3.1%. The ratio of male and female was 2: 1. There were no statistically significant differences on infection rate between boys (12/351, 3.4%) and girls (6/206, 2.9%). All of 18 positive CSF samples were negative for enterovirus, Epstein-Barr virus (EBV), human cytomegalovirus (HCMV), and herpes simplex virus 1 and 2 (HSV).HPeVs from 10 positive CSF samples were genotyped successfully, consisting of 7 HPeV3 and 3 HPeV1. In addition, 2 of 8 serum samples were positive for HPeV3 and 1 of 2 stool samples were positive for HPeV 1. HPeVs were identified in CSF from children aged from 15 days to 14 years, in which 7 cases were infants younger than 3 months and 5 cases were infants from 3 months to one year. Three children older than the age of 9 years (9, 13 and 14 years) were positive for HPeV. Most of the children (6/8) infected with HPeV3 were younger than 3 months and were diagnosed as sepsis, while the rest of HPeV3 positive children were diagnosed as meningitis and bronchopneumonia. HPeV3 infection clustered in August, while HPeV1 in January. CONCLUSION: HPeVs were associated with CNS infections and sepsis in hospitalized children in Beijing, especially in children younger than one year.HPeV3 was the predominant type identified in CSF.

Effect of human rhinovirus infection in pediatric patients with influenza-like illness on the 2009 pandemic influenza A(H1N1) virus.

BACKGROUND: Some research groups have hypothesized that human rhinoviruses (HRVs) delayed the circulation of the 2009 pandemic influenza A(H1N1) virus (A(H1N1)pdm09) at the beginning of Autumn 2009 in France. This study aimed to evaluate the relationship between HRV and A(H1N1)pdm09 in pediatric patients with influenza-like illness in Beijing, China. METHODS: A systematic analysis to detect A(H1N1)pdm09 and seasonal influenza A virus (FLU A) was performed on 4 349 clinical samples from pediatric patients with influenza-like illness during the period June 1, 2009 to February 28, 2010, while a one-step real-time RT-PCR (rRT-PCR) assay was used to detect HRV in 1 146 clinical specimens selected from those 4 349 specimens. RESULTS: During the survey period, only one wave of A(H1N1)pdm09 was observed. The percentage of positive cases for A(H1N1)pdm09 increased sharply in September with a peak in November 2009 and then declined in February 2010. Data on the monthly distribution of HRVs indicated that more HRV-positive samples were detected in September (2.2%) and October (3.3%), revealing that the peak of HRV infection in 2009 was similar to that of other years. Among the 1 146 specimens examined for HRVs, 21 (1.8%) were HRV-positive, which was significantly lower than that reported previously in Beijing (15.4% to 19.2%) (P < 0.01). Overall, 6 samples were positive for both A(H1N1)pdm09 and HRV, which represented a positive relative frequency of 1.60% and 2.08% HRV, considering the A(H1N1)pdm09-positive and -negative specimens, respectively. The odds ratio was 0.87 (95% CI 0.32; 2.44, P = 0.80). CONCLUSIONS: HRVs and A (H1N1)pdm09 co-circulated in this Chinese population during September and October 2009, and the HRV epidemic in 2009 did not affect A(H1N1)pdm09 infection rates in Beijing, China as suggested by other studies. However, the presence of A(H1N1)pdm09 might explain the unexpected reduction in the percentage of HRV positive cases during the period studied.

Four DNA extraction methods used in loop-mediated isothermal amplification for rapid adenovirus detection.

Loop-mediated isothermal amplification (LAMP) assays have become powerful tools for rapid diagnosis of infectious diseases. A more efficient, convenient and cheaper method for template preparation from the pellets or supernatants of nasopharyngeal aspirates was sought. Three DNA extraction methods (boiling, boiling in 1% Triton X-100, and treating with 0.02M NaOH) were compared with the commonly used DNAzol DNA extraction method. DNA preparations were then subjected to adenovirus (ADV) detection using LAMP assays and 119 clinical samples. The specificities for all three methods were 100% compared with the DNAzol method. The sensitivity of the boiling method was greater than that for the other two methods. The templates extracted from supernatants of nasopharyngeal aspirates using the boiling technique were further evaluated. Higher sensitivity (90.9%) and specificity (96.5%) were observed for LAMP assays compared with those from quantitative PCR assays. In conclusion, for template preparation, boiling supernatants of nasopharyngeal aspirates had comparable sensitivity and specificity with the DNAzol method. There were the added advantages that the boiling technique was simpler, cheaper, and had a shorter processing time. The boiling technique could become a suitable substitute for the DNAzol method when LAMP assays are used for ADV detection.