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1.
iScience ; 26(1): 105850, 2023 Jan 20.
Article in English | MEDLINE | ID: mdl-36636341

ABSTRACT

Lifespan is a life-history trait that undergoes natural selection. Telomeres are hallmarks of aging, and shortening rate predicts species lifespan, making telomere maintenance mechanisms throughout different lifespans a worthy topic for study. Alligators are suitable for the exploration of anti-aging molecular mechanisms, because they exhibit low or even negligible mortality in adults and no significant telomere shortening. Telomerase reverse transcriptase (TERT) expression is absent in the adult Alligator sinensis, as in humans. Selection analyses on telomere maintenance genes indicated that ATM, FANCE, SAMHD1, HMBOX1, NAT10, and MAP3K4 experienced positive selection on A. sinensis. Repressed pleiotropic ATM kinase in A. sinensis suggests their fitness optimum shift. In ATM downstream, Alternative Lengthening of Telomeres (ALT)-related genes were clustered in a higher expression pattern in A. sinensis, which covers 10-15% of human cancers showing no telomerase activities. In summary, we demonstrated how telomere shortening, telomerase activities, and ALT contributed to anti-aging strategies.

2.
Micromachines (Basel) ; 11(12)2020 Dec 21.
Article in English | MEDLINE | ID: mdl-33371443

ABSTRACT

Existing 3D printing techniques are still facing the challenge of low resolution for fabricating polymer matrix composites, inhibiting the wide engineering applications for the biomedical engineering (biomimetic scaffolds), micro fuel cells, and micro-electronics. In order to achieve high resolution fabrication of polylactic acid (PLA)/multi-walled carbon nanotube (MWCNT) composites, this paper presents an electric-field-driven (EFD) fusion jetting 3D printing method by combining the mixing effect and material feeding of the micro-screw and the necking effect of Taylor cone by the EFD. The effects of main process parameters (the carbon loading, the voltage, the screw speed, and the printing speed) on the line width and the printing quality were studied and optimized. To demonstrate the printing capability of this proposed method, meshes with line width of 30 µm to 100 µm and 1 wt.% to 5 wt.% MWCNT for the application of conductive biomimetic scaffold and the anisotropic flexible meshes were prepared. The electrical properties were investigated to present the frequency dependence of the alternating current conductivity and the dielectric loss (tanδ), and the microstructures of printed structures demonstrated the uniformly dispersed MWCNT in PLA matrix. Therefore, it provides a new solution to fabricate micro-scale structures of composite materials, especially the 3D conductive biomimetic scaffolds.

3.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-873499

ABSTRACT

@#Objective To understand the distribution and epidemic characteristics of common pathogens of pneumonia among hospitalized children in Suzhou. Methods Nasopharyngeal secretions were collected from hospitalized children with clinical pneumonia admitted to the respiratory department of Children's Hospital Affiliated to Suzhou University from April 2011 to March 2018 to detect common viral and bacterial pathogens of children's pneumonia. Results The total positive rate of pathogens was 75. 6% in the 4 765 clinical pneumonia cases. The positive rate of bacterial pathogens was 57. 4%. Streptococcus pneumoniae ( SP) was the highest,followed by Haemophilus influenzae ( H. i) ; The positive rate of viral pathogens was 44. 1%. Respiratory syncytial virus ( RSV) was the highest,followed by Bocavirus ( BoV) . The mixed infection rate of bacteria and virus was 25. 9%,and the most common types were RSV and SP,BoV and Streptococcus viride ( SV) . Conclusions SP,H.i,RSV and BoV are the main pathogens of clinical pneumonia in children. There are statistical differences in different age groups and seasons of hospitalized children's pneumonia in Suzhou. The mixed infection rate of bacteria and virus is high.

4.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-777913

ABSTRACT

Objective To estimate the outpatient rate of influenza-related influenza-like illness (ILI) for children younger than 5 years in Suzhou municipal districts. Methods From October 2011 to March 2017, we conducted a prospective surveillance program on ILI for children under 5 years in outpatient settings of Soochow University Affiliated Children’s Hospital (SCH). The throat swabs were collected and tested for influenza viruses by RT-PCR. Based on the healthcare utilization surveys and population data, the number of visits and the outpatient rate of influenza-related ILI for children younger than 5 years in Suzhou municipal districts were estimated. Results During 2011-2017, in total, there were 45 930 estimated influenza-related ILI cases younger than 5 years in Suzhou municipal districts, which consisted of 7 490 influenza A/H1N1 cases, 17 843 influenza A/H3N2 cases and 20 597 influenza B cases. The estimated outpatient rate of influenza-related ILI was 6.4% in 2011-2017, which was highest in 2011-2012, 20.5%, and the lowest in 2012-2013, 2.4%. Conclusion The number of visits and the outpatient rate of influenza-related ILI in children younger than 5 years was high in Suzhou municipal districts.

6.
Zhongguo Dang Dai Er Ke Za Zhi ; 10(2): 143-5, 2008 Apr.
Article in Chinese | MEDLINE | ID: mdl-18433531

ABSTRACT

OBJECTIVE: To understand the etiology of pneumonia in hospitalized patients less than 3 years of age. METHODS: A total of 316 children with pneumonia admitted to the Children's Hospital of Suzhou University in Jiangsu Province from March, 2006 to January, 2007 were enrolled in this study. Sputum samples were obtained by deep nasotracheal aspiration technique for bacterial and viral cultures. RESULTS: Of the 316 samples, specific microbial etiology was obtained in 192 cases (60.8%). Bacterial infection was found in 162 cases (51.3 %), viral infection in 19 cases (6.3%)and compound infection with virus and bacteria in 11 cases (3.5 %). Haemophilus influenzae was the most common agent (46 cases; 14.6%) in bacterial infection, followed by Streptococcus pneumoniae (32 cases; 10.1%). Respiratory syncycial virus (RSV) was the most common agent (12 cases; 4.0%) in viral infection, followed by adenovirus (11 cases; 3.6%). CONCLUSIONS: Bacterial infection was a leading cause of pneumonia in children less than 3 years of age in Suzhou area. Haemophilus influenzae was the most common agent, followed by Streptococcus pneumoniae.


Subject(s)
Pneumonia/etiology , Child, Preschool , Hospitalization , Humans , Infant , Infant, Newborn , Sputum/microbiology
7.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-325607

ABSTRACT

<p><b>OBJECTIVE</b>To understand the etiology of pneumonia in hospitalized patients less than 3 years of age.</p><p><b>METHODS</b>A total of 316 children with pneumonia admitted to the Children's Hospital of Suzhou University in Jiangsu Province from March, 2006 to January, 2007 were enrolled in this study. Sputum samples were obtained by deep nasotracheal aspiration technique for bacterial and viral cultures.</p><p><b>RESULTS</b>Of the 316 samples, specific microbial etiology was obtained in 192 cases (60.8%). Bacterial infection was found in 162 cases (51.3 %), viral infection in 19 cases (6.3%)and compound infection with virus and bacteria in 11 cases (3.5 %). Haemophilus influenzae was the most common agent (46 cases; 14.6%) in bacterial infection, followed by Streptococcus pneumoniae (32 cases; 10.1%). Respiratory syncycial virus (RSV) was the most common agent (12 cases; 4.0%) in viral infection, followed by adenovirus (11 cases; 3.6%).</p><p><b>CONCLUSIONS</b>Bacterial infection was a leading cause of pneumonia in children less than 3 years of age in Suzhou area. Haemophilus influenzae was the most common agent, followed by Streptococcus pneumoniae.</p>


Subject(s)
Child, Preschool , Humans , Infant , Infant, Newborn , Hospitalization , Pneumonia , Sputum , Microbiology
8.
Zhonghua Liu Xing Bing Xue Za Zhi ; 28(2): 165-8, 2007 Feb.
Article in Chinese | MEDLINE | ID: mdl-17649689

ABSTRACT

OBJECTIVE: To ascertain the genetic characterization and genotype of measles viruses isolated in Shanghai region, in 2005. METHODS: Measles virus was isolated from throat swab specimens collected from suspected measles cases and 450 bp fragment of C terminus of nucleprotein (N) gene was amplified by RT-PCR. Sequence analysis was conducted to ascertain the genotype and to compare the difference of nucleotide with other measles virus strain published in GenBank. RESULTS: 4 measles viruses were isolated from 10 throat swab specimens, and the sequence analysis indicated that they belonged to H1 genotype. The homogeneity of 450 nucleotides in the C terminal of the N gene was at 98%-98.2% as compared to H1 genotype (China93-7). They differed from genotype H2 (China94-1) at 6.4%-6.9% and from genotype A (Edmonston) at 6.7%-6.9%, from measles vaccine (Shanghail91) at 7.6%-8.0%. They differed from the other measles viral strain isolated in China in 1993 - 2005 at 0.2%-3.7%. The variation within 4 isolated measles viruses was at 0.7%-1.3%. CONCLUSION: It was H1 genotype measles viruses,which are the native viruses in China that led to the outbreak of measles in Shanghai, in 2005.


Subject(s)
Measles virus/genetics , China/epidemiology , Disease Outbreaks , Genotype , Humans , Measles/epidemiology , Measles/genetics , Measles virus/isolation & purification , Reverse Transcriptase Polymerase Chain Reaction , Sequence Analysis, DNA
9.
Chinese Journal of Epidemiology ; (12): 165-168, 2007.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-232328

ABSTRACT

<p><b>OBJECTIVE</b>To ascertain the genetic characterization and genotype of measles viruses isolated in Shanghai region, in 2005.</p><p><b>METHODS</b>Measles virus was isolated from throat swab specimens collected from suspected measles cases and 450 bp fragment of C terminus of nucleprotein (N) gene was amplified by RT-PCR. Sequence analysis was conducted to ascertain the genotype and to compare the difference of nucleotide with other measles virus strain published in GenBank.</p><p><b>RESULTS</b>4 measles viruses were isolated from 10 throat swab specimens, and the sequence analysis indicated that they belonged to H1 genotype. The homogeneity of 450 nucleotides in the C terminal of the N gene was at 98%-98.2% as compared to H1 genotype (China93-7). They differed from genotype H2 (China94-1) at 6.4%-6.9% and from genotype A (Edmonston) at 6.7%-6.9%, from measles vaccine (Shanghail91) at 7.6%-8.0%. They differed from the other measles viral strain isolated in China in 1993 - 2005 at 0.2%-3.7%. The variation within 4 isolated measles viruses was at 0.7%-1.3%.</p><p><b>CONCLUSION</b>It was H1 genotype measles viruses,which are the native viruses in China that led to the outbreak of measles in Shanghai, in 2005.</p>


Subject(s)
Humans , China , Epidemiology , Disease Outbreaks , Genotype , Measles , Epidemiology , Genetics , Measles virus , Genetics , Reverse Transcriptase Polymerase Chain Reaction , Sequence Analysis, DNA
10.
Phys Rev E Stat Nonlin Soft Matter Phys ; 73(5 Pt 2): 056308, 2006 May.
Article in English | MEDLINE | ID: mdl-16803038

ABSTRACT

The concept of inverse statistics in turbulence has attracted much attention in recent years. It is argued that the scaling exponents of the direct structure functions and the inverse structure functions satisfy an inversion formula. This proposition has already been verified by numerical data using the shell model. However, no direct evidence was reported for experimental three-dimensional turbulence. We propose to test the inversion formula using experimental data of three-dimensional fully developed turbulence by considering the energy dissipation rates instead of the usual efforts on the structure functions. The moments of the exit distances are shown to exhibit nice multifractality. The inversion formula between the direct and inverse exponents is then verified.

11.
Pediatr Infect Dis J ; 22(8): 739-42, 2003 Aug.
Article in English | MEDLINE | ID: mdl-12913778

ABSTRACT

BACKGROUND: Surveillance for pneumococcal respiratory illness was conducted in children hospitalized at Affiliated Pediatric Hospital of Fudan University in Shanghai from August 2000 to August 2001. METHODS: Sputum cultures were obtained from pediatric patients admitted with pneumonia or respiratory distress by tracheal aspirate. Blood cultures were also performed on a subset of patients. All pneumococcal isolates were serotyped and tested for antibiotic susceptibility. In addition clinical information on the patients including prior antibiotic history was abstracted. Streptococcus pneumoniae tracheal isolations were attempted in a total of 1013 pediatric patients hospitalized during this period. Among these samples 112 specimens were S. pneumoniae-positive. These positive isolates underwent serotyping and antibiotic susceptibility testing. RESULTS: Five serotypes (19F, 23F, 6A, 14, 6B) of S. pneumonia accounted for 81% (91 of 112 cases). Other serotypes accounted only for 12% (13 of 112 cases), and 7% (8 of 112 cases) of isolates could not be typed by quelling test. Only one blood culture isolate was positive, probably reflecting the frequent use of antibiotic treatment before hospitalization. Fifty-one and 8.0% of isolates had intermediate and high level penicillin resistance, respectively. Fifty-eight percent were resistant to ampicillin, 6.6% to cefazolin, 25.0% to cefaclor, 6.6% to ceftriaxone, 85.7% to erythromycin, 66.7% to clindamycin and 28.2% to chloramphenicol. Among 66 isolates that were not susceptible to penicillin, serotype 19F was the most common, followed by 23F and 14. CONCLUSION: S. pneumoniae is a common cause of respiratory illness requiring hospitalization in young children in Shanghai, with antibiotic resistance increasingly common. Five serotypes account for most disease.


Subject(s)
Anti-Bacterial Agents/pharmacology , Drug Resistance, Bacterial , Streptococcus pneumoniae/classification , Streptococcus pneumoniae/drug effects , Child , Child, Preschool , China , Cohort Studies , Female , Hospitalization , Hospitals, Pediatric , Humans , Infant , Infant, Newborn , Male , Microbial Sensitivity Tests , Pneumococcal Infections/diagnosis , Pneumococcal Infections/drug therapy , Respiratory Tract Infections/drug therapy , Respiratory Tract Infections/microbiology , Sampling Studies , Sensitivity and Specificity , Serotyping , Sputum/microbiology , Urban Population
12.
Chaos ; 13(3): 839-44, 2003 Sep.
Article in English | MEDLINE | ID: mdl-12946175

ABSTRACT

The largest Lyapunov exponent is an important invariant of detecting and characterizing chaos produced from a dynamical system. We have found analytically that the largest Lyapunov exponent of the small-scale wavelet transform modulus of a dynamical system is the same as the system's largest Lyapunov exponent, both discrete map and continuous chaotic attractor with one or two positive Lyapunov exponents. This property has been used to estimate the largest Lyapunov exponent of chaotic time series with several kinds of strong additive noise.

13.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-679839

ABSTRACT

Objectives To explore the type and subtype distribution of influenza viruses in influenza-like patients and the hemagglutinin(HA)genetic variation of influenza A viruses in Shang- hai and Wuxi during the influenza prevalent season from 2004 to 2006.Methods Throat swabs were collected from the influenza-like patients in the sentinel hospitals and during the outbreaks,and then inoculated into MDCK cells to isolate influenza viruses,which were subsequently identified by direct immunofluorescence(DIF)and reverse transcription-polymerase chain reaction(RT-PCR).HA seg- ments of influenza A viruses were sequenced to analyze the genetic variation of HA.Results One hundred and twenty-six strains of influenza viruses,including 53 H3N2,43 H1N1 and 30 influenza B viruses were isolated from August 2004 to September 2006,and 7 outbreaks.All these outbreaks oc- curred in February or March The pathogens were identified as H1N1 in one outbreak,H3N2 in two outbreaks,B in two outbreaks and mix infections in two outbreaks(1 H1N1 and B,1 H3N2 and B, respectively).By sequencing the HA segment,the H3 and H1 segments were all homologous to the isolates from different countries in the same period.Conclusion H3N2 and H1N1 are the major strains prevalent in Shanghai and Wuxi,which reach the peak from January to March No HA and NA recom- binant strains and new HA and NA subtypes are found in these areas.The variations of H1 and H3 are similar to those found in other countries.

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