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91.

Purpose

To examine the concordance of labor induction measures derived from birth certificate and hospital discharge data with each other and with maternal report.

Methods

Birth certificate data were linked with hospital discharge data and structured interviews of 2,851 mothers conducted 1 month after first childbirth. Those who reported that a doctor or nurse tried to cause their labor to begin, and were not in labor before that event, were classified as undergoing labor induction. The mothers were aged 18 to 35 years at study entry and delivered at 78 hospitals (76 in Pennsylvania and 2 out of state) from 2009 to 2011.

Results

The labor induction rate was 34.3% measured by maternal report, 29.4% by birth certificate data, and 26.2% by hospital discharge data. More than one-third of the women who reported labor induction were not reported as having been induced in the birth certificate data (33.6%), with similar results for the hospital discharge data (36.5%). The rate of underreporting of labor induction in the birth certificate data was higher for inductions occurring before 39 weeks of gestation (43.9%) than for inductions at 39 weeks or later (29.9%; p < .0001). Agreement between birth certificate and hospital discharge data was relatively low (kappa = 0.56), as was agreement between maternal report and birth certificate data (kappa = 0.58), and maternal report and hospital discharge data (kappa = 0.60).

Conclusions

Both the birth certificate and hospital discharge data exhibit relatively poor agreement with maternal report of labor induction and seem to miss a substantial portion of labor inductions.  相似文献   
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目的探讨草血竭纯化部分对于小鼠甲型H1N1流感的疗效。方法采用滴鼻法建立甲型H1N1流感病毒感染小鼠模型,通过灌胃途径给予不同剂量的草血竭,以给予奥司他韦者为阳性对照,以未给予药物者为病毒对照组。观察14d内小鼠生活状态,计算小鼠肺指数,检测肺组织内流感病毒核酸相对量和病毒滴度。结果甲型H1N1流感病毒对小鼠的半数致死量为10-6。阳性对照组和草血竭高、中剂量组小鼠的存活率均为100%,平均生存日数均为14d,草血竭低剂量组小鼠的存活率为42.86%,平均生存日数为9.14d,而病毒对照组小鼠的存活率及平均生存日数分别为0和3.57d。不同组别小鼠平均生存日数比较,差异有统计学意义(F=8.53,P=0.02);阳性对照组、高剂量组、中剂量组、低剂量组小鼠平均生存日数均高于病毒对照组(P0.05)。阳性对照组和草血竭高剂量、中剂量、低剂量组及病毒对照组肺指数分别为:(0.84±0.07)%、(0.81±0.07)%、(0.84±0.10)%、(0.84±0.10)%和(1.42±0.12)%,差异有统计学意义(P=0.03);病毒核酸相对量分别为:0.37±0.11、0.42±0.06、0.42±0.06、0.65±0.19和1.00±0.06,差异有统计学意义(P=0.04);病毒滴度分别为:2.49±0.12、2.35±0.29、2.43±0.15、2.46±0.12和2.80±0.16,差异有统计学意义(P=0.04)。阳性对照组和草血竭各剂量组的肺指数、肺组织内流感病毒核酸相对量和病毒滴度均低于病毒对照组(P0.05);而阳性对照组的上述指标与草血竭各剂量组比较,差异无统计学意义(P0.05)。结论草血竭纯化部分在体内对甲型H1N1流感病毒具有抑制作用,能够改善甲型H1N1流感小鼠的肺组织的病变,降低病死率。  相似文献   
95.
《Vaccine》2018,36(40):5990-5998
We previously demonstrated that intramuscular immunization with virus-like particles (VLPs) composed of the haemagglutinin (HA), neuraminidase (NA), and matrix (M1) proteins of A/meerkat/Shanghai/SH-1/2012 (clade 2.3.2.1) protected mice from lethal challenge with viruses from other H5 HPAI clades. The inclusion of additional proteins that can serve as immunological adjuvants in VLPs may enhance adaptive immune responses following vaccination, and oral vaccines may represent the safest choice. Here, we report the generation of H5N1 VLPs composed of the viral HA, NA, and M1 proteins and membrane-anchored forms of the Escherichia coli heat-labile enterotoxin B subunit protein (LTB) or the Toll-like receptor 5 ligand flagellin (Flic). Mice intramuscularly or orally immunized with VLPs containing LTB or Flic generated greater humoural and cellular immune responses than those administered H5N1 VLPs without LTB or Flic. Intramuscular immunization with VLPs protected mice from lethal challenge with homologous or heterologous H5N1 viruses irrespective of whether the VLPs additionally included LTB or Flic. In contrast, oral immunization of mice with LTB- or Flic-VLPs conferred substantial protection against lethal challenge with both homologous and heterologous H5N1 influenza viruses, whereas mice immunized orally with VLPs lacking LTB and Flic universally succumbed to infection. Mice immunized orally with LTB- or Flic-VLPs showed 10-fold higher virus-specific IgG titres than mice immunized with H5N1-VLPs lacking LTB or Flic. Collectively, these results indicate that the inclusion of immunostimulatory proteins, such as LTB and Flic, in VLP-based vaccines may represent a promising new approach for the control of current H5N1 HPAI outbreaks by eliciting higher humoural and cellular immune responses and conferring improved cross-clade protection.  相似文献   
96.
Human behaviour plays an important role in the spread of emerging infectious diseases, and understanding the influence of behaviour changes on epidemics can be key to improving control efforts. However, how the dynamics of individual behaviour changes affects the development of emerging infectious disease is a key public health issue. To develop different formula for individual behaviour change and introduce how to embed it into a dynamic model of infectious diseases, we choose A/H1N1 and Ebola as typical examples, combined with the epidemic reported cases and media related news reports. Thus, the logistic model with the health belief model is used to determine behaviour decisions through the health belief model constructs. Furthermore, we propose 4 candidate infectious disease models without and with individual behaviour change and use approximate Bayesian computation based on sequential Monte Carlo method for model selection. The main results indicate that the classical compartment model without behaviour change and the model with average rate of behaviour change depicted by an exponential function could fit the observed data best. The results provide a new way on how to choose an infectious disease model to predict the disease prevalence trend or to evaluate the influence of intervention measures on disease control. However, sensitivity analyses indicate that the accumulated number of hospital notifications and deaths could be largely reduced as the rate of behaviour change increases. Therefore, in terms of mitigating emerging infectious diseases, both media publicity focused on how to guide people's behaviour change and positive responses of individuals are critical.  相似文献   
97.
《Vaccine》2018,36(33):5030-5036
Influenza A H7N9 virus has caused five outbreak waves of human infections in China since 2013 and posed a dual challenge to public health and poultry industry. There is an urgent need to develop an effective vaccine to reduce its pandemic potential. In the present study, we evaluated the biochemical characteristics and immunogenicity of two H7 virus-like particles (VLPs) composed of the matrix 1 (M1) and hemagglutinin of wild-type (HA-WT) or hemagglutinin of whose transmembrane domain replaced by that from H3N2 subtype (HA-TM). H7 VLPs-WT and H7 VLPs-TM could assemble and release into the supernatant of Sf9 cells and they had similar morphological characteristics. However, compared to H7 VLPs-WT, H7 VLPs-TM had more trimeric HA proteins and could better resist thermal changes. In mice H7 VLPs-TM induced higher titers of HI, IgG, IgG2a and IFN-γ, and provided better protection against homologous and heterologous H7N9 viruses (no matter belonging to Yangtze River Delta or Pearl River Delta) challenge with less weight loss and higher survival rate. In summary, H7 VLPs-TM represents a potential strategy for the development of H7N9 vaccines.  相似文献   
98.
《Vaccine》2018,36(5):698-706
BackgroundTo support vaccination programs in developing countries, a 4-dose vial presentation of pneumococcal non-typeable Haemophilus influenzae protein D-conjugate vaccine (PHiD-CV) was developed. This study assessed immunologic non-inferiority and safety of the investigational PHiD-CV 4-dose versus licensed 1-dose vial presentation in infants.MethodsIn this phase III, mono-center, observer-blind study in Bangladesh, 6–10-week-old infants were randomized 1:1 to receive PHiD-CV primary vaccination (at ages 6, 10, 18 weeks) and a booster dose (at age 9 months) with a 4-dose vial (with preservative, 4DV group) or 1-dose vial (preservative-free, 1DV group). DTPw-HBV/Hib was (co)-administered per study protocol and polio, measles and rubella vaccines as part of the national immunization program. Non-inferiority of PHiD-CV 4-dose versus 1-dose vial for each vaccine pneumococcal serotype (VT) and vaccine-related serotype 19A in terms of antibody geometric mean concentration (GMC) was assessed (criterion: upper limit of 2-sided 95% confidence interval of antibody GMC ratios [1DV/4DV] <2-fold). Immune responses were measured. Solicited, unsolicited and serious adverse events (AEs) were evaluated.ResultsOf 320 infants (160 per group) vaccinated during the primary vaccination phase, 297 received a booster. Non-inferiority was demonstrated for each VT and 19A. One month post-primary vaccination, for most VT, ≥97.9% of infants in each group had antibody concentrations ≥0.2 μg/mL; for 19A ≥ 80.1% reached this threshold. Pneumococcal antibody responses and opsonophagocytic activity for each VT and 19A were within similar ranges between groups after primary and booster vaccination, as were anti-protein D responses. Booster immune responses were observed in both groups. Reported AEs were within similar ranges for both presentations.ConclusionImmunologic non-inferiority of PHiD-CV 4-dose vial (with preservative) versus PHiD-CV 1-dose vial (preservative-free) was demonstrated. Immune responses and reactogenicity following primary/booster vaccination were within similar ranges for both presentations. PHiD-CV 4-dose vial would help improve access and coverage in resource-limited countries.Clinical Trial Registry: NCT02447432.  相似文献   
99.
《Vaccine》2018,36(46):6944-6952
A ferret challenge study was conducted to address the efficacy of the egg-based and Madin-Darby canine kidney (MDCK)-based live attenuated influenza vaccine (LAIV) strains. Vaccines derived as 6:2 reassortants from the A/Leningrad/134/17/57 master donor strain and the HA and NA components from the A/California/07/2009 (A/Cal)- and A/Michigan/45/2015 (A/Mich)-like strains of type A H1N1 influenza virus were used in the study. Monovalent, trivalent and quadrivalent formulations of the LAIV containing either of the two H1N1 strains were analysed. A total of ten groups of six animals each were immunised intranasally (i.n.) with a single dose of 0.5-ml vaccine formulation or placebo and challenged on day 28 with the homologous wild-type A/Cal or A/Mich strain. Immune response post immunisation and virus replication post challenge were studied.Both the strains derived from embryonated eggs or MDCK cells, irrespective of the vaccine valency, were capable of rendering complete protection from virus replication in the lung. The A/Mich vaccine strain showed higher immune titres and efficacy than the A/Cal vaccine strain in all the vaccine formulations. The haemagglutination inhibition and virus neutralisation antibody titres were induced, and the reduction in the virus load in the respiratory tract was observed to be higher in animals treated with the monovalent formulation compared to the trivalent and quadrivalent formulations. Overall, it appears that the monovalent formulations render better protection from infection and would therefore be the best candidate during a pandemic.  相似文献   
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目的探讨柚皮苷对H_2O_2诱导的H9c2心肌细胞凋亡的保护作用及机制。方法体外培养H9c2心肌细胞,用H_2O_2诱导建立细胞凋亡模型。实验设对照组、模型组、柚皮苷低、中、高剂量组(10、20、40μmol/L),噻唑蓝法检测细胞活力并用显微镜观察各组细胞形态;原位末端标记法检测H9c2心肌细胞凋亡情况;RT-PCR及Western blot法检测凋亡相关因子Bcl-2、Bax、caspase-3 m RNA及蛋白表达。结果与对照组比较,模型组细胞凋亡率[(17.2±2.1)%]明显升高(P<0.01);与模型组比较,10、20、40μmol/L柚皮苷组细胞凋亡率[分别为(10.7±1.9)%、(5.7±1.2)%、(6.4±1.5)%]均下降(均P<0.05)。与对照组比较,模型组H9c2心肌细胞Bcl-2蛋白表达水平(0.76±0.16)明显下调,Bax、caspase-3蛋白表达水平[分别为(5.42±0.52)、(1.09±0.11)]均上调(均P<0.01);与模型组比较,10、20、40μmol/L柚皮苷组H9c2心肌细胞Bcl-2蛋白表达水平[分别为(1.37±0.11)、(1.65±0.09)、(1.65±0.15)]均上调,Bax、caspase-3蛋白表达水平[分别为(2.78±0.55)、(3.43±0.15)、(2.69±0.26)和(0.59±0.08)、(0.77±0.06)、(0.82±0.05)]均下调(均P<0.05)。结论柚皮苷对H_2O_2诱导的H9c2心肌细胞损伤具有一定保护作用,其机制可能与其对凋亡信号途径的抑制作用有关。  相似文献   
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