A Bilayer Method for Measuring Toughness and Strength of Dental Ceramics.

The ever-increasing usage of ceramic materials in restorative dentistry necessitates a simple and effective method to evaluate flexural strength σF and fracture toughness KC. We propose a novel method to determine these quantities using a bilayer specimen composed of a brittle plate adhesively bonded onto a transparent polycarbonate substrate. When this bilayer structure is placed under spherical indentation, tunneling radial cracks initiate and propagate in the lower surface of the brittle layer. The failure analysis is based on previous theoretical relationships, which correlate σF with the indentation force P and layer thickness d, and KC with P and mean length of radial cracks. This work examines the accuracy and limitations of this approach using a wide range of contemporary dental ceramic materials. The effect of layer thickness, indenter radius, load level, and length and number of radial cracks are carefully examined. The accuracy of the predicted σF and KC is similar to those obtained with other concurrent test methods, such as biaxial flexure and 3-point bending (σF), and bending specimens with crack-initiation flaws (KC). The benefits of the present approach include treatment for small and thin plates, elimination of the need to introduce a precrack, and avoidance of dealing with local material nonlinearity effects for the KC measurements. Finally, the bilayer configuration resembles occlusal loading of a ceramic restoration (brittle layer) bonded to a posterior tooth (compliant substrate).

[A review of the influence of the 1956 Senior Teacher Training Program on Medical History].

The 1956 Senior Teacher Training Program on Medical History, hosted by the Institute of Traditional Chinese Medicine of the Ministry of Health, was the first teacher training program on the history of medicine in higher education in P. R. China. It was designed in the context of "Learning from the Soviet Union" for teaching reformation, "Integrating Western and Traditional Chinese Medicine" and performing the policy of "Blossom of Hundred Flowers and Contention of Hundred Schools of Thought" (by Mao Zedong for encouraging a variety of thinking conflicts) after the birth of the New China. The teaching management for the program was well organised, with a strong staff, and outcomes. A few of the trainees from this program were engaged in teaching and research of the history of medicine, and made outstanding academic achievements and promoted the teaching and research of the history of medicine in Chinese universities in the second half of the 20th century. This program also provides a valuable reference for teacher training programs as well as teaching and research of medical history today.

[Advances in the research of heterotopic ossification caused by burns].

Heterotopic ossification is a rare complication of burns, and its incidence and risk factors are still unclear. Through summarizing the literature on heterotopic ossification caused by burns at home and abroad, the author searched for the risk factors of heterotopic ossification after burn and the new progress of its prevention and treatment. It was realized that the size, depth and healing time of burn wounds were related to heterotopic ossification; the nonsteroidal anti-inflammatory drugs, radiation therapy, and their combination therapy can be used for the prevention of heterotopic ossification; surgery is an effective means of treating heterotopic ossification.

Inhibitory effect of TGF-ß gene modified human amniotic mesenchymal stem cells on rejection after xenotransplantation of peripheral nerves.

OBJECTIVE: To explore the inhibitory effect of transforming growth factor-beta (TGF-ß) gene modified human amniotic mesenchymal stem cells on rejection after xenotransplantation of peripheral nerves. MATERIALS AND METHODS: In this study, 6 placentas collected in our hospital were selected as the source of human amniotic mesenchymal stem cells. A total of 60 C57BL/6 experimental mice (mouse sciatic nerves were removed before the experiment) were taken as research objects. Mice were randomly divided into experimental group 1, experimental group 2 and experimental group 3 (xenogenous peripheral nerves were introduced to all experimental groups), and a control group (autologous peripheral nerves were introduced). Among them, TGF-ß gene modified (overexpression) human amniotic mesenchymal stem cells were introduced to experimental group 1; TGF-ß gene modified (inhibition) human amniotic mesenchymal stem cells were introduced to experimental group 2; normal human amniotic mesenchymal stem cells were introduced to experimental group 3; and autologous sciatic nerves were introduced to control group. The messenger ribonucleic acid (mRNA) and protein expressions of the TGF-ß in different human amniotic mesenchymal stem cells were detected by quantitative polymerase chain reaction (qPCR) and Western blotting, respectively. Mouse sciatic nerve function in each group after 2 weeks of procedures was detected via the CatWalk system. Expression level of interleukin-22 (IL-22) in the peripheral tissues of transplanted nerves and blood was detected using immunohistochemistry and enzyme-linked immunosorbent assay (ELISA). Its mRNA level was examined via fluorescence quantitative PCR. RESULTS: TGF-ß1 was highly expressed in mice of experimental group 1, but lowly expressed in experimental group 2 relative to that of experimental group 3 (p<0.05). CatWalk test results revealed that the main indexes in experimental group 1 were superior to those in other groups, while the main indexes in experimental group 2 were inferior to those in other groups. According to immunohistochemistry and ELISA results, there were significant differences in the expression level of IL-22 in mice of different treatment groups (p<0.05). IL-22 level was the lowest in control group [(5.05±0.15) pg/mL], followed by that in experimental group 1 [(6.52±0.24) pg/mL], and it was the highest in experimental group 2 [(9.47±0.31) pg/mL]. CONCLUSIONS: Human amniotic mesenchymal stem cells overexpressing TGF-ß can inhibit rejection after xenotransplantation of peripheral nerves.

[Clinical efficacy of different vascular reconstruction on adult moyamoya disease].

Objective: To investigate the clinical efficacy of superficial temporal artery -middle cerebral artery combined with encephalo-duro-arterio-myo-synangiosis (STA-MCA+EDAMS) and encephalo-duro-arterio-myo-synangiosis (EDAMS) in the treatment of adult moyamoya disease. Methods: The clinical data of 47 adult patients with moyamoya disease who received vascular reconstruction in the Department of Neurosurgery of Taizhou Hospital of Zhejiang Province from January 2014 to January 2018 were retrospectively analyzed. Among them, 21 patients received EDAMS alone (EDAMS group, 14 patients with hemorrhagic moyamoya disease, 7 patients with ischemic moyamoya disease), 26 patients received STA-MCA combined with EDAMS (STA-MCA+EDAMS group, 17 patients with hemorrhagic moyamoya disease, 9 patients with ischemic moyamoya disease). Cerebral hemodynamics at 1 day before surgery and 3 and 6 months after surgery were compared. The clinical efficacy and postoperative complications of the two methods were compared at 3 and 6 months postoperatively in hemorrhagic and ischemic types. Results: For hemorrhagic moyamoya disease, the remission rate (94.1%) at 6 months after surgery in the STA-MCA + EDAMS group was higher than that in the EDAMS group (57.1%), and the difference was statistically significant (P<0.05). The CBF and CBV in the STA-MCA+EDAMS group were higher than those in the EDAMS group at 3 and 6 months after operation, and the MTT and TPP were lower than those in the EDAMS group, but there was no significant difference between the two groups (all P>0.05). For hemorrhagic moyamoya disease and ischemic moyamoya disease, the total incidence of postoperative complications of the two surgical methods was different, but the difference was not statistically significant (both P>0.05). Conclusion: Superficial temporal artery -middle cerebral artery combined with encephalo-duro- arterio-myo-synangiosis (STA-MCA+EDAMS) and encephalo-duro-arterio-myo-synangiosis (EDAMS) can significantly improve neurological function and cerebral hemodynamics in adult moyamoya disease patients with high safety.

Genetic diversity of Merozoite Surface Protein-1 gene block 2 allelic types in Plasmodium falciparum isolates from Malaysia and Thailand.

Malaria is the most common vector-borne parasitic disease in Malaysia and Thailand, especially in Malayan Borneo and along the Thailand border areas, but little is known about the genetic diversity of the parasite. Present study aims to investigate the genetic diversity of Plasmodium falciparum isolates in these two countries and eventually contributes to more effective malaria control strategies, particularly in vaccine and antimalarial treatment. One hundred and seventy three P. falciparum isolates were collected from Malaysia (n = 67) and Thailand (n = 106) and genotyped using nested PCR targeting the polymorphic region of MSP-1, block 2. Sequence analysis was conducted to investigate the allele diversity of the isolates. Three allelic families were identified in Malaysian and Thailand P. falciparum isolates, MAD20, K1 and RO33. Sequence analysis revealed that there were 5 different MAD20, 1 K1 and 2 different RO33 for Malaysian isolates. Thailand isolates exhibited greater polymorphism because there were 13 different MAD20, 6 different K1 and 2 different RO33 identified in this study. Multiclonal infections were observed for the isolates in both countries, however, low multiplicity of infection (MOI) was observed for Malaysian (1.1) and Thailand (1.2) isolates. Phylogenetic analysis showed that P. falciparum isolates of Malaysia and Thailand were clustered in the same group for all the allelic families. Population structure of P. falciparum isolates in Malaysia and Thailand exhibit extensive genetic polymorphism but showed high similarities as well as comparable MOI.

Genetic diversity of Merozoite Surface Protein-1 gene block 2 allelic types in Plasmodium falciparum isolates from Malaysia and Thailand

@#Malaria is the most common vector-borne parasitic disease in Malaysia and Thailand, especially in Malayan Borneo and along the Thailand border areas, but little is known about the genetic diversity of the parasite. Present study aims to investigate the genetic diversity of Plasmodium falciparum isolates in these two countries and eventually contributes to more effective malaria control strategies, particularly in vaccine and antimalarial treatment. One hundred and seventy three P. falciparum isolates were collected from Malaysia (n = 67) and Thailand (n = 106) and genotyped using nested PCR targeting the polymorphic region of MSP-1, block 2. Sequence analysis was conducted to investigate the allele diversity of the isolates. Three allelic families were identified in Malaysian and Thailand P. falciparum isolates, MAD20, K1 and RO33. Sequence analysis revealed that there were 5 different MAD20, 1 K1 and 2 different RO33 for Malaysian isolates. Thailand isolates exhibited greater polymorphism because there were 13 different MAD20, 6 different K1 and 2 different RO33 identified in this study. Multiclonal infections were observed for the isolates in both countries, however, low multiplicity of infection (MOI) was observed for Malaysian (1.1) and Thailand (1.2) isolates. Phylogenetic analysis showed that P. falciparum isolates of Malaysia and Thailand were clustered in the same group for all the allelic families. Population structure of P. falciparum isolates in Malaysia and Thailand exhibit extensive genetic polymorphism but showed high similarities as well as comparable MOI.

An evolution-based DNA-binding residue predictor using a dynamic query-driven learning scheme.

DNA-binding proteins play a pivotal role in various biological activities. Identification of DNA-binding residues (DBRs) is of great importance for understanding the mechanism of gene regulations and chromatin remodeling. Most traditional computational methods usually construct their predictors on static non-redundant datasets. They excluded many homologous DNA-binding proteins so as to guarantee the generalization capability of their models. However, those ignored samples may potentially provide useful clues when studying protein-DNA interactions, which have not obtained enough attention. In view of this, we propose a novel method, namely DQPred-DBR, to fill the gap of DBR predictions. First, a large-scale extensible sample pool was compiled. Second, evolution-based features in the form of a relative position specific score matrix and covariant evolutionary conservation descriptors were used to encode the feature space. Third, a dynamic query-driven learning scheme was designed to make more use of proteins with known structure and functions. In comparison with a traditional static model, the introduction of dynamic models could obviously improve the prediction performance. Experimental results from the benchmark and independent datasets proved that our DQPred-DBR had promising generalization capability. It was capable of producing decent predictions and outperforms many state-of-the-art methods. For the convenience of academic use, our proposed method was also implemented as a web server at .

Protein-protein interaction network construction for cancer using a new L1/2-penalized Net-SVM model.

Identifying biomarker genes and characterizing interaction pathways with high-dimensional and low-sample size microarray data is a major challenge in computational biology. In this field, the construction of protein-protein interaction (PPI) networks using disease-related selected genes has garnered much attention. Support vector machines (SVMs) are commonly used to classify patients, and a number of useful tools such as lasso, elastic net, SCAD, or other regularization methods can be combined with SVM models to select genes that are related to a disease. In the current study, we propose a new Net-SVM model that is different from other SVM models as it is combined with L1/2-norm regularization, which has good performance with high-dimensional and low-sample size microarray data for cancer classification, gene selection, and PPI network construction. Both simulation studies and real data experiments demonstrated that our proposed method outperformed other regularization methods such as lasso, SCAD, and elastic net. In conclusion, our model may help to select fewer but more relevant genes, and can be used to construct simple and informative PPI networks that are highly relevant to cancer.

TNFSF4 polymorphisms are associated with systemic lupus erythematosus in the Malaysian population.

Tumour necrosis factor superfamily 4 (TNFSF4) gene has been reported to be associated with systemic lupus erythematosus (SLE) susceptibility due to its encoding for OX40L protein that can increase autoantibody production and cause imbalance of T-cell proliferation. The purpose of this study was to investigate the association of TNFSF4 rs2205960, rs1234315, rs8446748 and rs704840 with SLE in the Malaysian population. A total of 476 patients with SLE and 509 healthy controls were recruited. Real-time polymerase chain reaction (PCR) was applied to genotype the selected single nucleotide polymorphisms (SNPs). Allelic and genotypic frequencies of each SNP were calculated for each ethnic group, and association test was performed using logistic regression. The overall association of each SNP in Malaysian patients with SLE was determined with meta-analysis. The frequency of minor T allele of TNFSF4 rs2205960 was significant in Chinese and Indian patients with SLE, with P values of 0.05 (OR = 1.27, 95% CI: 1.00-1.61) and 0.004 (OR = 3.16, 95% CI: 1.41-7.05), respectively. Significant association of minor G allele of rs704840 with SLE was also observed in Chinese (P = 0.03, OR = 1.26, 95% CI: 1.02-1.56). However, after Bonferroni correction, only T allele of rs2205960 remained significantly associated with Indian cohort. Overall, minor G allele of rs704840 showed significant association with SLE in the Malaysian population with P values of 0.05 (OR = 1.20, 95% CI: 1.00-1.43). We suggested TNFSF4 rs704840 could be the potential SLE risk factors in the Malaysian population.

Nutritional State Predicts All-Cause Death Independent of Comorbidities in Geriatric Patients with Coronary Artery Disease.

OBJECTIVE: To explore whether nutritional risk is associated with poor outcomes independent of complicated clinical status in older patients with coronary artery disease (CAD). DESIGN: Cohort study. SETTING: Patients referred for coronary angiography in West China Hospital, Sichuan University, China. PARTICIPANTS: 1772 patients with angiographic documented CAD whose age was above 65 years. MEASUREMENTS: Nutritional state was appraised using geriatric nutritional risk index (GNRI). Nutritional risk was defined as the GNRI below 98. The event rate of all-cause death was observed among patients with nutritional risk and those without. RESULTS: During a median follow-up period of 27 months, 224 patients died. Multivariate Cox regression analysis showed that nutritional risk was associated with all-cause death (adjusted hazard ratio 1.99; 95% confidence interval 1.35-2.95; P=0.001). Subgroup analysis verified the association between nutritional risk and death among patients with distinct clinical features, comorbidities, and medication. There was no interaction between nutritional risk and clinical characteristics with regard to all-cause death. CONCLUSION: Nutritional state is independently associated with the risk of all-cause death in geriatric patients with CAD. Whether nutritional support in appropriate patients improves clinical outcomes deserves further investigation.

Prevalence of hypertension after living-donor liver transplantation: a prospective study.

BACKGROUND: Hypertension is common among patients who have undergone liver transplantation and is a major contributor to cardiovascular events. Few studies have studied the risk factors associated with post-liver transplantation (LT) hypertension. This prospective study assessed the prevalence of post-LT hypertension and associated preoperative risk factors. METHODS: From May 2008 to December 2009, 79 normotensive adult patients (≥ 18 years old) who underwent living-donor LT with a median follow up of 4.79 ± 0.88 years were enrolled. Patients' pre-LT demographics, clinical data, pre-LT diabetes, and immunosuppressive agents used after LT were studied for their association with post-LT hypertension. RESULTS: The prevalence of post-LT hypertension was 49.4%. The independent risk factors for post-living-donor LT hypertension were pre-LT systolic blood pressure (SBP; odds ratio [OR], 1.04; 95% confidence interval [CI], 1.00-1.09; P = .039) and post-LT administration of mammalian target of rapamycin (mTOR) inhibitors (OR, 4.08; 95% CI, 1.40-11.94; P = .010). Pre-LT diabetes had a negative predictive value (OR, 0.15; 95% CI, 0.03-0.74; P = .019). Neither age, male sex, smoking, pre-LT serum cholesterol and triglyceride levels, tacrolimus, nor glucocorticoid was associated with post-LT hypertension. CONCLUSIONS: The prevalence of hypertension is high after LT. Higher pre-LT SBP and post-LT mTOR inhibitor administration predispose patients to post-LT hypertension.

Efficacy of transcatheter aortic valve implantation in patients with aortic stenosis and reduced LVEF. A systematic review.

BACKGROUND: Transcatheter aortic valve implantation (TAVI) is safe and effective for patients with aortic stenosis (AS) who have a high operative risk. However, there is still debate on the effect of TAVI in AS patients with reduced left ventricular ejection fraction (REF). The objective of the review is to clarify the efficacy of TAVI and the impact of REF on the 30-day and midterm mortality in these patients. METHODS: Studies on TAVI were searched in PubMed, Embase, and the Cochrane Library databases and were included in this review following predefined criteria. Data were extracted and pooled risk ratios (RR) were synthesized to explore the relationship between REF and 30-day plus midterm mortality. RESULTS: Twenty-eight studies comprising 14,099 patients were included in the analysis of the association of REF with the prognosis of patients after TAVI. An average increase in left ventricular ejection fraction of 8-10 % was observed among these patients after TAVI. REF was not related to the 30-day mortality [RR = 1.90, 95 % confidence interval (CI) = 0.80-4.47]; however, it was related to the midterm mortality (RR = 1.49, 95 %CI = 1.14-1.93) of patients undergoing TAVI. Patients with low-flow and low-gradient AS had a higher 30-day mortality (RR = 1.54, 95 %CI = 1.11-2.13) and midterm mortality rate (RR = 1.69, 95 %CI = 1.33-2.14) compared with AS patients without these characteristics. The mortality of TAVI patients was significantly lower than that of those undergoing conservative therapy, and was similar to that of patients undergoing surgical aortic valve replacement. CONCLUSION: REF was not associated with 30-day mortality, but it was associated with the midterm mortality of TAVI patients. Patients with REF could benefit from TAVI compared with conservative therapy.

Lean mass index, body fat and survival in Chinese patients with coronary artery disease.

BACKGROUND: 'Obesity paradox' was not consistently observed in Asians with coronary artery disease (CAD). AIM: The study investigated the association between body composition and outcomes in Chinese patients with CAD. DESIGN: Cohort study. METHOD: A total of 3280 patients with angiographically validated CAD were consecutively included. Body fat (BF) percentage and lean mass index (LMI) were evaluated using the Clínica Universidad de Navarra-Body Adiposity Estimator. The rate of mortality from any cause was compared across groups classified by the quartiles of LMI. RESULTS: During a median period of 24 months, 288 (8.8%) participants died. There was a close association between increasing LMI and reducing mortality rate. However, univariate analyses did not find protective effect of BF on survival. After adjusting for age, sex, diabetes, current smoking, systolic blood pressure, creatinine, white blood cell count, haemoglobin and medication, Cox regression analyses showed that the significant relation between higher quartiles (Q) of LMI and survival benefit (Q4, hazard ratio 0.58 (95% confidence interval: 0.36-0.94) vs. Q3, 0.60 (0.39-0.91) vs. Q2, 0.60 (0.41-0.88) vs. Q1, reference) remained. CONCLUSION: Low LMI but not BF predicts all-cause mortality in Chinese patients with CAD.

Increased interventricular septum wall thickness predicts all-cause death in patients with coronary artery disease.

BACKGROUND: There is debate regarding the predictive value of interventricular septum (IVS) wall thickness for adverse events. AIMS: The study investigated the association between the severity of thickened IVS and all-cause death in Chinese patients with coronary artery disease (CAD). METHODS: A total of 2297 CAD patients verified by angiography was consecutively included. Patients were grouped according to the severity of thickened IVS. Cox regression analysis was conducted to determine the independent prognostic value of thickened IVS for all-cause death. RESULTS: During a median follow up of 25 months, 149 patients died. A gradient increase in the risk of death was observed across thickened IVS groups. Compared to patients with normal IVS thickness, the adjusted hazard ratio (HR) was 1.49 (95% confidence interval (CI) 1.00-2.23, P = 0.05) and 2.13 (95% CI 1.29-3.54, P = 0.003) for all-cause death in those with mildly and moderately/severely thickened IVS respectively. For one unit increase in IVS thickness, the risk of all-cause death was elevated by 14% (adjusted HR 1.14, 95% CI 1.05-1.24, P = 0.003). In patients with normal indexed left ventricular mass, thickened IVS was also demonstrated as an independent risk factor for all-cause death. CONCLUSION: Thickened IVS can be served as a reliable marker for predicting all-cause death in Chinese patients with CAD, even in those with normal left ventricular mass.

HLA variants rs9271366 and rs9275328 are associated with systemic lupus erythematosus susceptibility in Malays and Chinese.

BACKGROUND: Human leukocyte antigen (HLA) antigens and genes have long been reported associated with systemic lupus erythematosus (SLE) susceptibility in many populations. With the advance in technologies such as genome-wide association studies, many newly discovered SLE-associated single-nucleotide polymorphisms (SNPs) have been reported in recent years. These include HLA-DRB1/HLA-DQA1 rs9271366 and HLA-DQB1/HLA-DQA2 rs9275328. Our aim was to investigate these SNPs in a Malaysian SLE cohort. MATERIALS AND METHODS: SNPs rs9271366 and rs9275328 were screened across 790 Malaysian citizens from three ethnic groups (360 patients and 430 healthy volunteers) by Taqman SNP genotyping assays. Allele and genotyping frequencies, Hardy-Weinberg equilibrium, Fisher's exact test and odds ratio were calculated for each SNP and ethnic group. Linkage disequilibrium and interaction between the two SNPs were also evaluated. RESULTS: The minor allele G and its homozygous genotype GG of HLA-DRB1/HLA-DQA1 rs9271366 significantly increased the SLE susceptibility in Malaysian patients, including those of Malay and Chinese ethnicity (odds ratio (OR) > 1, p < 0.05). As for HLA-DQB1/HLA-DQA2 rs9275328, the minor allele T and the heterozygous genotype CT conferred protective effect to SLE in Malaysians, as well as in Malays and Chinese, by having OR < 1 and p value <0.05. Both SNPs did not show associations to SLE in Indians. D' and r (2) values for the two SNPs in LD analysis were 0.941 and 0.065, respectively, with haplotype GC and AT being significantly associated with SLE (p < 5.0 × 10(-4)) after 10,000 permutations were performed. The MDR test clustered the genotype combinations of GG and CC, and AG and CC of rs9271366 and rs9275328, accordingly, as high-risk group, and the two SNPs interacted redundantly by removing 1.96% of the entropy. CONCLUSIONS: Our findings suggest that in addition to some classical HLA variants, rs9271366 and rs9275328 are additional polymorphisms worth considering in the Malaysian and possibly in a larger Asian SLE scenario.

Processing of facial expressions of emotions in healthy volunteers: an exploration with event-related potentials and personality traits.

AIMS OF THE STUDY: Previous studies have shown that event-related potentials (ERPs) are modulated by anxiety or psychopathic personality traits. Therefore, we hypothesized that the automatic processing of facial expressions of emotions (FEE) is also correlated with related disordered personality traits. METHODS: Thirty-seven healthy volunteers underwent both an "oddball" ERP recording to facial expressions of Anger, Happiness, Sadness, and Neutral, and a test of the Dimensional Assessment of Personality Pathology (DAPP). RESULTS: Mean reaction time was longer in response to anger than to other facial expressions. Facial expressions of Anger, Happiness and Sadness did not affect N1 (N170). By contrast, Happiness elicited a delayed P2, Anger elicited both a smaller N2 and a delayed P3b, and both Happiness and Anger elicited a P3b of higher amplitude. In addition, P3a latencies to Happiness were negatively correlated with DAPP Identity problems, and P3b latencies to Happiness were negatively correlated with DAPP Stimulus seeking, Callousness, Passive aggressivity, and Narcissism. CONCLUSION: Our study demonstrates that Anger implicitly captures attentional resources, and Happiness triggers more facilitated processing in individuals with dissocial traits.

Hemagglutinin protein of Asian strains of human influenza virus A H1N1 binds to sialic acid--a major component of human airway receptors.

Hemagglutinin (HA) protein plays an important role in binding the influenza virus to infected cells and therefore mediates infection. Deposited HA sequences of 86 Asian strains of influenza A (H1N1) viruses during the first outbreak were obtained from the NCBI database and compared. Interaction of the HA protein of influenza A (H1N1) virus with the human sialic acid receptor was also studied using bioinformatics. Overall, not more than three single-point amino acid variants/changes were observed in the HA protein region of influenza A (H1N1) virus from Asian countries when a selected group sequence comparison was made. The bioinformatics study showed that the HA protein of influenza A (H1N1) binds to the sialic acid receptor in human airway receptors, possibly key to air-borne infection in humans.