This study aims to perform a survey of genetic variation in neuraminidase (NA) gene of influenza A/H3N2 virus, as well as related resistance to NA inhibitors, in Qinghai Province of China, 2010 to 2012. Strains of influenza A/H3N2 isolated during an influenza survey from 2010 to 2012 in Qinghai were enrolled by random sampling. Viral RNA was extracted and amplified by RT-PCR. Purified PCR products were sequenced thereafter. Genetic analysis of nucleic acid and the derived amino acid sequences was performed by MEGA 4.0. Phylogenetic trees were also constructed. Strains isolated during 2010-2011 in this study clustered closely with World Health Organization (WHO) 2010-2012 reference vaccine strain A/Perth/16/2009 and 2008-2010 reference vaccine strain A/Brisbane/10/2007 on the phylogenetic tree, while the 2012 isolates were located on another branch. In analysis of derived amino acid sequences, the 2010 isolates mutated at K81T, the 2011 isolates mutated at I26V and D127N, while the 2012 isolates mutated at E41K, P46A, I58V, T71N, L81P, D93G, D127N, D151N, and I307M. The D151N mutation added a glycosylation site to the activity center of NA. No significant variation was discovered in H3N2 NA gene of 2010-2011 isolates in Qinghai, China. Isolates of 2012 were found with significant mutation, which has the potential of inducing minor resistance to NA inhibitors like zanamivir and oseltamivir.
Amino Acid Sequence ; China ; Humans ; Influenza A Virus, H3N2 Subtype ; classification ; enzymology ; genetics ; isolation & purification ; Influenza, Human ; virology ; Molecular Sequence Data ; Neuraminidase ; chemistry ; genetics ; Phylogeny ; Sequence Alignment ; Viral Proteins ; chemistry ; genetics

Objective To investigate the variations of elastic modulus and hardness of human dentin with aging and location.Methods The non-carious third molars were collected and divided into youth group,middle-aged group and elderly group.Nanoidentation test was conducted on the dentin specimens from multiple regions to test their mechanical properties.Results The elastic modulus and hardness in outer and middle dentin were greater than those in inner dentin;the elastic modulus and hardness increased with the aging in each region of the dentin.Conclusions The dentin shows a gradient mechanical property.The stiffness and hardness in middle and outer dentin are greater than those in inner dentin.The deformation resistance in middle and outer dentin is stronger than that in inner dentin.Meanwhile,elastic modulus and hardness of the dentin increase with the aging.

Objective To investigate the variations of elastic modulus and hardness of human dentin with aging and location. Methods The non-carious third molars were collected and divided into youth group, middle-aged group and elderly group. Nanoidentation test was conducted on the dentin specimens from multiple regions to test their mechanical properties. Results The elastic modulus and hardness in outer and middle dentin were greater than those in inner dentin; the elastic modulus and hardness increased with the aging in each region of the dentin. Conclusions The dentin shows a gradient mechanical property. The stiffness and hardness in middle and outer dentin are greater than those in inner dentin. The deformation resistance in middle and outer dentin is stronger than that in inner dentin. Meanwhile, elastic modulus and hardness of the dentin increase with the aging.

OBJECTIVETo evaluate various kinds of sequences and modified dynamic contrast-enhanced MRI methods in the diagnosis of pancreatic carcinoma.

METHODSForty-nine pancreatic carcinoma patients proved by histopathology or clinical examination and follow-up underwent MR examination. Plain MR sequences included: T1-weighted 2D FLASH, T1 WI 3D VIBE, TSE T2 WI and HASTE with FS. Modified dynamic contrast-enhanced scanning procedures were coronal scaning with 3D FLASH and axial scaning using T1 WI 3D VIBE sequences in turn for the upper abdominal area and pancreatic area. The coronal imaging were used to obtain 3D peripancreatic vessels during arterial phase and portal vein phase scanning, respectively. The axial imaging were used to detect the tumor in pancreatic parenchymal phase and delayed phase scanning, respectively. Final scanning for the whole upper abdomen was performed using T1 WI 2D FLASH axial sequence.

RESULTS(1) Of 49 lesions in these patients, 45 showed hypo-intensity and 4 iso-intensity on 3D VIBE. Forty-six lesions showed hypo-intensity and 3 isointensity on 2D FLASH. On TSE T2 + FS, lesion contour was not clear enough; 3 of them displayed isointensity, the other showed iso- or hyper-intensity. (2) During pancreatic parenchymal phase, 48 lesions showed hypo-intensity and 39 ring enhancement. Twenty-four lesions displayed marginal tubercle and inner compartment enhancement during portal vein and delayed phase. Six lesions showed iso- or hyper-intensity in delayed phase. (3) Thirty-seven patients underwent surgical exploration. MRI and MRA had a good correlation with surgical findings for peripancreatic vessels which were diagnosed as being invasive or noninvasive by tumors except three superior mesenteric arteries and four superior mesenteric veins being misdiagnosed.

CONCLUSIONAs"one-stop-shop" MRI examination, modified MRI sequences consisting of dynamic coronal and axial contrast-enhanced scanning is feasible and helpful in diagnosing, staging and assessing the resectability for pancreatic carcinoma.

Adenocarcinoma ; diagnosis ; pathology ; secondary ; Adult ; Aged ; Aged, 80 and over ; Cholangiopancreatography, Magnetic Resonance ; Female ; Humans ; Image Enhancement ; Imaging, Three-Dimensional ; Liver Neoplasms ; diagnosis ; secondary ; Magnetic Resonance Angiography ; Magnetic Resonance Imaging ; methods ; Male ; Mesenteric Artery, Superior ; pathology ; Middle Aged ; Neoplasm Invasiveness ; Pancreatic Neoplasms ; diagnosis ; pathology ; Reproducibility of Results ; Sensitivity and Specificity

OBJECTIVETo investigate the CT and MRI manifestatitions of intraductal papillary mucinous neoplasm (IPMN) of the pancreas.

METHODSBoth clinical and imaging data of 12 pathologically confirmed intraductal papillary mucinous neoplasm, of the pancreas were retrospectively analyzed.

RESULTSThe pancreatic IPMN can be classified into two types based on CT image: the branch duct IPMN (n=7) originated from the head and uncinate process of the pancreas. The tumor consisted of lobulated or clustered small cyst lesions with septa among them, the wall and septa can be enhanced; the combined IPMN (n=5) involved branch ducts of the uncinate process as well as the main pancreatic ducts with dilatation (diameter: 4-7 mm), one of these involved the branch ducts along the pancreatic body. The pancreatic IPMN was mainly found in elderly patient with a chief clinical symptoms of abdominal pain and/or pancreatitis.

CONCLUSIONThe intraductal papillary mucinous neoplasm of the pancreas enjoys specific features in CT and MRI image, which are helpful to the diagnosis.

Adult ; Aged ; Aged, 80 and over ; Carcinoma, Pancreatic Ductal ; diagnosis ; diagnostic imaging ; Carcinoma, Papillary ; diagnosis ; diagnostic imaging ; Cystadenocarcinoma, Mucinous ; diagnosis ; diagnostic imaging ; Diagnosis, Differential ; Female ; Humans ; Magnetic Resonance Imaging ; Male ; Middle Aged ; Pancreatic Ducts ; diagnostic imaging ; pathology ; Pancreatic Neoplasms ; diagnosis ; diagnostic imaging ; Retrospective Studies ; Sensitivity and Specificity ; Tomography, X-Ray Computed

OBJECTIVETo evaluate the ability of multidetector computed tomography (MDCT) in differentiating ovarian tumors from non-ovarian masses.

METHODSForty-two cases with pelvic masses were examined with 16-row MDCT. All source image of each case was put into workstation for multi-planar reconstruction (MPR) and curved planar reconstruction(CPR). Axial image combined with 2D image was used for determining the relationship of the mass to ovarian vascular pedicle and identifying the normal ovary, which was compared with postoperative pathologic result and the finding during operation. All the data was compared using Fisher's exact test.

RESULTSThere were 28 ovarian tumors and 14 non-ovarian tumors in this series. If the ovarian vascular pedicle sign was used for determining whether the tumor was from the ovary or not, the sensitivity, specificity, positive predictive value, negative predictive value and accuracy was 89.3%, 85.7%, 92.6%, 80.0% and 88.1%, respectively, with a significant difference in differentiating the tumor from the ovary or non-ovarian organs (P <0.05). If the identification of full normal ovary was used to determine non-ovarian origin of the tumor, the sensitivity, specificity, positive predictive value, negative predictive value and accuracy was 50.0%, 100.0%, 100.0%, 80.0% and 83.3%, respectively, also with a significant difference in differentiating the tumors from the ovary or non-ovarian organs (P <0.05).

CONCLUSIONMDCT can clearly show the relationship of the tumor to the normal ovary and its vascular pedicle, which is very helpful in differentiating the ovarian tumors from a non-ovarian masses.

Adult ; Aged ; Cystadenocarcinoma, Mucinous ; diagnostic imaging ; Cystadenocarcinoma, Serous ; diagnostic imaging ; Cystadenoma, Mucinous ; diagnostic imaging ; Cystadenoma, Serous ; diagnostic imaging ; Diagnosis, Differential ; Female ; Gastrointestinal Stromal Tumors ; diagnostic imaging ; Humans ; Leiomyoma ; diagnostic imaging ; Middle Aged ; Ovarian Neoplasms ; diagnostic imaging ; Ovary ; blood supply ; diagnostic imaging ; Retroperitoneal Neoplasms ; diagnostic imaging ; Teratoma ; diagnostic imaging ; Tomography, X-Ray Computed ; methods ; Uterine Neoplasms ; diagnostic imaging ; Young Adult

OBJECTIVETo investigate the role of MRI in evaluating the peripancreatic vessel invasion and resectability of pancreatic carcinoma based on the comparison of MRI image with surgical exploration, and try to establish the criteria for assessment of the sensitivity, specificity and accuracy of resectability.

METHODSForty-one pancreatic carcinoma patients confirmed by pathology received preoperative plain and contrast enhanced MRI scan, and 37 of them had additional coronal MRA scan. Peripancreatic vessel invasion was preoperatively assessed based on MRI features, and the vessel invasion degree from the uninvolved to the severely involved was divided into 6 grades represented by 1, 2a, 2b, 3a, 3b and 4, respectively. Compared with the findings during the surgery, the sensitivity and specificity of each vessel invasion grade were studied and the receiver operator characteristic curve (ROC) was drawn. The sensitivity, specificity, positive predictive value, negative predictive value and accuracy of resectability evaluation based on 2 and 2a degree were calculated respectively. The resectability of involved arteries and veins of grade 2 were also analyzed.

RESULTSOf the 41 patients, 22 had resectable tumor, with 20 curative resection and 2 palliative. Compared with the findings during surgery, seven vessels including three arteries and four veins were not correctly interpreted by MRI. If grade 1,2a,2b,3a and 3b was used as the resectable standard,respectively, the sensitivity to predict the unresectbility was 78.3%, 84.8%, 67.4%, 56.5% and 47.8%, respectively. Receiver operator characteristic curve demonstrated that grade 2a was the optimal critical point. The sensitivity, specificity, positive predictive value, negative predictive value and accuracy of grade 2a in predicting the unresectbility were 84.8%, 98.5%, 92.9%, 96.6% and 95.9%.

CONCLUSIONOur data showed that grade 2a (tumor involvement < 2 cm long and < 1/2 circumference of the vessel) may be more sensitive and accurate in predicting the resectability, which may be considered as the line of demarcation between the respectable and unresectable cases in clinical practice.

Adult ; Aged ; Carcinoma, Pancreatic Ductal ; diagnosis ; pathology ; surgery ; Celiac Artery ; pathology ; Cholangiopancreatography, Magnetic Resonance ; Female ; Hepatic Artery ; pathology ; Humans ; Image Enhancement ; Magnetic Resonance Imaging ; methods ; Male ; Mesenteric Artery, Superior ; pathology ; Mesenteric Veins ; pathology ; Middle Aged ; Neoplasm Invasiveness ; Neoplasm Staging ; Pancreas ; blood supply ; Pancreatectomy ; methods ; Pancreatic Neoplasms ; diagnosis ; pathology ; surgery ; Portal Vein ; pathology ; Predictive Value of Tests ; Sensitivity and Specificity

OBJECTIVETo describe the status of nutrition and health related indices in the Chinese population.

METHODSA stratified multi-stage cluster sampling was used from 31 provinces, autonomous regions, and municipalities. The survey was done in 2002, including data gathered from questionnaires, interviews, physical examinations, measurement of biochemical indices, and dietary investigation.

RESULTSCereals accounted for 48.5% of all the sources of energy in urban and 61.4% in rural populations. Daily mean percentages of calories for total fat were 35.0% in urban and 27.5% in rural areas. The prevalence rates of stunting and underweight were 14.3% and 7.8% respectively in young children under 5-year-old. The prevalence of vitamin A deficiency was 9.3% in Chinese children aged 3-12 years old. The total prevalence of anemia was 15.2% in general population of all ages. The prevalence of anemia in young adults was significantly higher in women than in men. The total prevalence rates of overweight and obesity were 17.6% and 5.6%, respectively. The prevalence rates of hypertension, diabetes, hypercholesteremia, hypertriglyceridemia, or low serum high density lipoprotein cholesterol were 18.8%, 2.6%, 2.9%, 11.9%, 7.4% respectively in Chinese adults aged 18 and over. The rates of awareness, treatment, and under control among hypertensives were 30.2%, 24.7%, and 25.0%, respectively. Significant regional and age differences were revealed in the dietary habit and the prevalence of various diseases. The prevalence of diseases associated with malnutrition were higher in rural than in urban areas. In contrast, the prevalence of conditions associated with overconsumption and inappropriate dietary patterns were higher in urban than in rural populations.

CONCLUSIONChinese people were currently suffering from both problems on nutrition related issues and burdens of diseases which were characterized in nutrient deficiencies and overconsumption, malnutrition and noncommunicable conditions associated with overconsumption and inappropriate diet. The difference of nutrition and health status between rural and urban people was also seen.

Adolescent ; Adult ; Anemia ; epidemiology ; Child ; Child, Preschool ; China ; Chronic Disease ; epidemiology ; Diabetes Mellitus ; epidemiology ; Diet ; statistics & numerical data ; Eating ; Energy Intake ; Female ; Growth and Development ; Health Surveys ; Humans ; Hypertension ; epidemiology ; Infant ; Lipids ; blood ; Male ; Middle Aged ; Nutrition Surveys ; Obesity ; epidemiology ; Pregnancy ; Vitamin A Deficiency ; epidemiology ; Young Adult

Objective To analyze the contact failure of monolithic lithium disilicate CAD/CAM crowns by experiment and numerical simulation, and explore the influences of adhesives aging in water on load-bearing capacity of the crowns. Methods The specimens of sectioned monolithic lithium disilicate crowns were designed and manufactured, and evenly divided into two groups and stored in the air and in the distilled water for 30 days, respectively. The specimens were then subjected to monotonic contact loads to compare and analyze their load-bearing capacity. The fractured surfaces and adhesive interfaces of the specimens were observed by scanning electronic microscope. Meanwhile, the stress distribution on the crowns was calculated by numerical simulation to analyze the adhesives aging influence on load-bearing capacity of the crowns. Results The fracture loads on crowns stored in the air and in the water were (561.51 ± 65.66) N and (398.09 ± 90.20) N, respectively, indicating a significant difference. The tensile stress increased considerably at lower surface of the ceramic crown due to the reduction of adhesive strength at the interface of ceramic crown and substrate, which could increase the propensity of contact failure. Conclusions The adhesives aging in water reduces the bonding strength, and accordingly changes the tensile stress distributions, which can lower the load bearing capacity of the lithium disilicate crowns. The research finding provides references for the design and manufacturing of all-ceramic CAD/CAM restored crowns in clinic.

Objective To understand the epidemic situation and the source of infection of the reemerge human rabies in Qinghai. Methods We collected the data on human rabies and the data on the cases of multi- victims bitten by the identical dog, and also the laboratory data of the nucleoprotein ( N) gene of rabies virus from the samples which were detected by reverse transcription-polymerase chain reaction (RT-PCR) and direct immunofluorescence assay (DFA) from 2012 to 2017, to describe the epidemiological characteristics of human rabies and the prevalence of rabies virus in host animals, and to explore the source of infection of reemerge human rabies. Results A total of 7 human cases were reported in 2012-2017 in Qinghai province, among which 1 was bitted by wolf, 2 were bitted by stray dogs, 3 were bitted by domestic dogs which injured by stray dogs or wolfs. A total of 892 canine brain tissue samples were collected, from which 46 positive samples were detected with the positive rate of 5.16% (95% CI：3.70%-6.61%). The positive samples were collected from the nomadic region, which were consistent had the location of the human rabies. The samples collected from the cases of multi-victims bitten by the identical dog/animal had the positive rate of 73.08%, and 4 out of 7 human rabies were exposed to the cases of multi-victims bitten by the identical dog/animal. Genetic sequencing of the rabies virus detected from canine brain tissue samples were belong to China IV lineage, which was closely related to the Arctic clade. Conclusions The reemerging rabies happened in nomadic region of Qinghai province could be a consequence of spillover from wildlife especially from wolfs. The better surveillance system covering the human, livestock and wildlife should be set up to mitigate the rabies virus spread from the wildlife.