Virological surveillance of pandemic (H1N1) 2009 virus and its genetic characteristics in Hunan Province, 2009-2011 / 病毒学报

To understand and master the dynamic variation of the pandemic influenza A (H1N1) 2009 in Hunan province from 2009 to 2011, and to know the genetic characteristics and drug resistance of the pandemic (H1N1) 2009 viruses. Throat swab specimens of influenza-like illness patients were collected from sentinel hospitals and tested for influenza by fluorescent PCR or virus isolation methods. Partial isolates were selected for sequencing. The sequences were used for phylogenetic analysis by MEGA 5. 05 software. From the 20th week of 2009 to the 52nd week of 2011, 17 773 specimens were tested. 3 831 specimens were influenza-positive with a positive rate of 21. 6%, of which 1 794 were positive specimens of pandemic (H1N1) 2009, accounting for 46. 8%00 of the influenza-positives. There were 2 epidemic peaks of pandemic (H1N1) 2009, which were in the 41st-53rd week of 2009 and the 1st-12nd week of 2011, respectively. The HA genes of 23 strains that were selected for sequencing had close relationship; the distribution of strains in the phylogenetic tree was basically in chronological order. The complete genome sequence analysis showed that all of 8 gene segments of 7 strains were homologous to the vaccine strain, and there was no gene reassortment. The HA amino acid sites of the 23 strains were highly similar to the vaccine strain (98. 2% - 100. 0% in homology), but all 23 strains had P83S, S203T and 1321V mutations. The 222 site mutation that may lead to enhanced virulence was found in the A/Hunan/YQ30/2009 strain. The mutation was D222E. There was no oseltamivir resistance mutation found in all strains. The pandemic (H1N1) 2009 in Hunan province from 2009 to 2011 had a bimodal distribution. There was no large-scale variation of virus genes. The clinical use of oseltamivir was still effective. Key words: Pandemic (H1N1) 2009; Surveillance; Genetic characteristics

Experimental study on adipose-derived stem cells combined with acellular dermal matrix particles for vocal fold injection / 中华耳鼻咽喉头颈外科杂志

<p><b>OBJECTIVE</b>To explore the feasibility of adipose-derived stem cells (ASC) combined with micronized acellular dermal matrix (MADM) for vocal cord injection.</p><p><b>METHODS</b>The adipose-deprived stem cells were harvested from rabbit adipose tissue in vitro. The 3rd generation of ASC was labeled with DiI (1,1-dioctadecyl-3,3,3,3-tetramethylindocarbocyanine perchlorate) and cultured with MADM to form a complex. The adhesion of ASC to MADM was observed by fluorescence microscope and electron microscope. The proliferation of ASC on MADM was evaluated by 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxy methoxyphenyl)-2-(4-sulfonyl)-2H-tetrazolium, inner salt (MTS). Three days after the culture, the complex was mixed with appropriate amount of collagen, and then injected into the unilateral vocal cord of the rabbit. The animals were sacrificed 2, 4, 8 weeks after injection, the survival time and distribution of ASC in vocal fold were tested, and the responses of vocal cord to ASC-MADM and the degradation of MADM were observed.</p><p><b>RESULTS</b>The ASC adhered to MADM and grew well (P < 0.05 or < 0.01), showing good compatibility with MADM in vocal cord tissue. The complex of ASC-MADM could be injected into the rabbit vocal cords, while no adverse reactions was observed in the vocal cord by endoscope, frozen section and HE staining. ASC could survive for 8 weeks in vocal cords, and no inflammatory cell infiltration was observed.</p><p><b>CONCLUSIONS</b>MADM is an ideal scaffold material and shows perfect compatibility with ASC which can adhere and proliferate well on it. The complex of ASC-MADM can be injected into the vocal cord and can survive. There is no adverse reaction in vocal cords.</p>

The isolation, cultivation and identification of laryngeal mucosal mesenchymal stem cells / 中华耳鼻咽喉头颈外科杂志

<p><b>OBJECTIVE</b>To investigate the presence of mesenchymal stem cells (MSC) in laryngeal mucosa, and to seek for the method to isolate, cultivate and identify these cells.</p><p><b>METHODS</b>Normal laryngeal mucosa was obtained from patients with laryngeal carcinoma during surgery, and the generating mesenchymal cells was obtained by digestive method. The cell growth curve was evaluated by 3-(4.5-methylthiazol-2yl)-2.5-diphenyltetrazolium bromide (MTT) assay. Colony forming cell assay was used to screen different morphologic colonies and evaluate clone formation ability. Flow cytometry was performed for the expression of the cells of the 4th passage surface marker profiles. Multiple differentiation potentials were confirmed by adipogenic, osteogenic and neural lineages induction.</p><p><b>RESULTS</b>MTT assay and colony forming cell assay showed that laryngeal mucosa MSC had a relatively rapid proliferation capacity and a relatively high clone formation capacity (clone formation rate 7.1%). Flow cytometry analysis revealed that the laryngeal mucosa MSC were positive for CD29 (16.9%), CD44 (97.4%), CD90 (89.5%), CD105 (85.9%), CD146 (2.5%) and stro-1 (20.4%), but negative for CD34 (1.2%) and CD45 (0.8%). Laryngeal mucosa MSC undergone adipogenic, osteogenic and neural lineages induction were positive for oil red staining, alizarin red staining and S100 staining respectively, which suggested that laryngeal mucosa MSC could differentiate into adipogenic, osteogenic and neural lineages.</p><p><b>CONCLUSION</b>This study demonstrated that MSC with rapid proliferative capacity and multiple differentiation potential could be obtained from lamina propria of laryngeal mucosa.</p>

Serological survey of pandemic influenza A (H1N1) virus infection among population in Hunan Province / 中华实验和临床病毒学杂志

<p><b>OBJECTIVE</b>To understand the infection condition and analytical methods of Influenza A (H1N1) virus in the population of Hunan Province during different periods.</p><p><b>METHODS</b>Quick surveys on the positive rate of Influenza A (H1N1) virus hemagglutination inhibition (HI) test have been conducted for 5 times successively from November 2009 to March 2010 in 14 medical and health institutions of Changsha city, whose results were then compared with those from the sampling surveys of whole Hunan province.</p><p><b>RESULTS</b>2131 subjects were involved in this study; the total population standardized rates of antibody positive investigated for 5 times were 9.32% , 14.62%, 31.08%, 28.43% and 22.80% respectively; the population of 6-17-years-old has the highest rate of antibody positive; only 9.84% of the antibody positive subjects attributed to vaccine inoculation; there was no significant difference in the standardized positive rates between the quick serological surveys and the corresponding sampling survey of Hunan province (P > 0.05).</p><p><b>CONCLUSION</b>The positive rate of A (H1N1) virus antibody reached the peak in late January 2010; quick investigations in small region could be used to evaluate the infection prevalence during pandemic of infectious diseases.</p>

Risk factors of death cases of hand-foot-and-mouth disease in Hunan province / 中华预防医学杂志

<p><b>OBJECTIVE</b>To study risk factors of death cases of hand foot and mouth diseases (HFMD) in Hunan province, so as to provide scientific evidence for further prevention and control.</p><p><b>METHODS</b>The 105 death cases of HFMD between January and October, 2010 in Hunan Province were selected as case group; and the 210 survival cases of serious HFMD, which were matched by gender and resident places with a ratio at 2:1 in the same period in Hunan were selected as control group. The basic information, hospitalized experience and previous medical history had been surveyed and the relevant risk factors were analyzed by single factor and multi-factor logistic regression.</p><p><b>RESULTS</b>In case group, 79.05% (83/105) of the cases lived in rural area and 9.52% (10/105) of the cases lived in urban-rural midst area. In control group, 87.62% (184/210) of the cases lived in rural area and 11.43% (24/210) of the cases lived in urban-rural midst area. In case group, 59.05% (62/105) of the patients first visited rural (private) clinics and 20.00% (21/105) first visited community hospitals in villages and towns; while in control group, 43.81% (92/210) and 13.33% (28/210) chose rural (private) clinics and community hospitals in villages and towns as the first choice respectively.22.86% (24/105) of the case group and 39.05% (82/210) of the control group were diagnosed as HFMD in their first visit to hospital.27.62% (29/105) of the case group and 7.14% (15/210) in control group were provided pyrazolone in the treatment. For glucocorticoid, 80.95% (85/105) and 5.71% (6/105) of the case group were given as treatment by rural (private) clinics and community hospitals in villages and towns separately; while the proportions in the control group were 41.43% (87/210) and 0.48% (1/210) respectively. For antibiotics, 35.24% (37/105) and 23.81% (25/105) of the case group were prescribed by rural (private) clinics and community hospitals in villages and towns separately; while the percentages in the control group were 15.71% (33/210) and 7.14% (15/210). 3.81% (4/105) of the case group and 11.90% (25/210) of the control group were vaccinated in one month before the onset. The results of single-factor logistic regression indicated that living in rural areas (OR = 0.075, 95%CI: 0.016 - 0.343) and in rural-urban midst areas (OR = 0.069, 95%CI: 0.013 - 0.368), diagnosis of HFMD in the first visit to hospital (OR = 0.463, 95%CI: 0.271 - 0.788) and vaccination one month before the onset (OR = 0.293, 95%CI: 0.099 - 0.866) were four protective factors; while rural (private) clinics as the first choice (OR = 4.717, 95%CI: 1.891 - 11.767), community hospital in villages and towns as the first choice (OR = 5.250, 95%CI: 1.883 - 14.641), medication of pyrazolone (OR = 4.961, 95%CI: 2.520 - 9.766), medication of glucocorticoid in rural (private) clinics (OR = 6.009, 95%CI: 3.435 - 10.510) and in community hospital in villages and towns (OR = 12.667, 95%CI: 1.505 - 106.638), medication of antibiotics in rural (private) clinics (OR = 2.918, 95%CI: 1.690 - 5.040) and in community hospital in villages and towns (OR = 4.062, 95%CI: 2.036 - 8.108) were seven risk factors. The results of multi-factors logistic regression showed that medication of pyrazolone (OR = 2.311, 95%CI: 1.062 - 5.030), medication of glucocorticoid in rural (private) clinics (OR = 5.480, 95%CI: 3.039 - 9.880), medication of antibiotics in rural (private) clinics (OR = 2.430, 95%CI: 1.301 - 4.538) and medication of antibiotics in community hospitals in villages and towns (OR = 3.344, 95%CI: 1.477 - 7.569) were the risk factors of death of HFMD.</p><p><b>CONCLUSION</b>The risk factors of HFMD deaths include the medication of pyrazolone, glucocorticoid and antibiotics by rural (private) clinics and medical institutions in villages and towns. The department concerned should revise the technical manual to standardize the medication of the above drugs.</p>