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41.
The purpose of this study was to determine whether the efficacy of taxoid treatment combined with epidermal growth factor receptor (EGFR) inhibition is dose and sequence dependent in head and neck squamous cell carcinoma. Three head and neck squamous cell carcinoma cell lines, chosen on the basis of their diverse EGFR expression levels, were treated with docetaxel, erlotinib, or both. The combination index was calculated using the Chou-Talalay equation. Propidium iodide staining with fluorescence-activated cell sorting analysis was used to evaluate the effects of drugs on cell cycle changes. Western blot analysis was used to determine the effects of agents on cell signaling pathways. Administration of low-dose docetaxel (0.1-3 nmol/l) concurrently or before erlotinib had additive cytotoxic effects in two cell lines but was antagonistic in one line, whereas low-dose docetaxel after erlotinib was synergistic in all cell lines. In contrast, high-dose docetaxel (40 nmol/l) resulted in more apoptosis when given before, rather than after or concurrently with, erlotinib. Low-dose docetaxel induced an accumulation of cells in the sub-G0 phase of the cell cycle with no mitotic arrest or apoptosis, whereas high-dose docetaxel induced mitotic arrest and apoptosis. The low and high doses of docetaxel had opposite effects on EGFR expression: a decrease and an increase, respectively. The dose of docetaxel affects sequence-dependent cytotoxicity when docetaxel is combined with an EGFR inhibitor. The mechanism for this difference is a combination of the dose-dependent effects of docetaxel on the mode of cell death and on EGFR expression. 相似文献
42.
Eyal Leshem Mary Wikswo Leslie Barclay Eric Brandt William Storm Ellen Salehi Traci DeSalvo Tim Davis Amy Saupe Ginette Dobbins Hillary A. Booth Christianne Biggs Katie Garman Amy M. Woron Umesh D. Parashar Jan Vinjé Aron J. Hall 《Emerging infectious diseases》2013,19(8):1231-1238
During 2012, global detection of a new norovirus (NoV) strain, GII.4 Sydney, raised concerns about its potential effect in the United States. We analyzed data from NoV outbreaks in 5 states and emergency department visits for gastrointestinal illness in 1 state during the 2012–13 season and compared the data with those of previous seasons. During August 2012–April 2013, a total of 637 NoV outbreaks were reported compared with 536 and 432 in 2011–2012 and 2010–2011 during the same period. The proportion of outbreaks attributed to GII.4 Sydney increased from 8% in September 2012 to 82% in March 2013. The increase in emergency department visits for gastrointestinal illness during the 2012–13 season was similar to that of previous seasons. GII.4 Sydney has become the predominant US NoV outbreak strain during the 2012–13 season, but its emergence did not cause outbreak activity to substantially increase from that of previous seasons. 相似文献
43.
Optimization of chitosan film as a substitute for animal and human epidermal sheets for in vitro permeation of polar and non polar drugs 总被引:2,自引:0,他引:2
The present investigation is aimed at preparing chitosan films capable of simulating the flux of modal drugs, 5-fluorouracil (5-FU) and indomethacin (INDO), across rat, rabbit and human cadaver epidermal sheets. Application of statistical design revealed that the concentration of chitosan, crosslinking time and concentration of crosslinking agent significantly influenced the in vitro flux of 5-FU and INDO across chitosan films. Multiple linear regression revealed a linear influence of all these active variables on 5-FU and INDO flux. It was deduced from atomic absorption spectroscopic analyses, DSC and IR spectroscopic data that 5% (m/V) sodium tripolyphosphate (NaTPP) produced optimum crosslinking of chitosan films. The in vitro permeation of both 5-FU and INDO across optimized film formulations was found to be comparable to that obtained across rat, rabbit and human epidermal sheets. These results indicate that optimized chitosan films have a potential to be developed as a substitute for animal and human cadaver epidermal sheets for preliminary in vitro permeation studies. 相似文献
44.
Mohamed-Lemine Cheikh-brahim Ahmed Jorg Heukelbach Abdellahi Weddih Abdelkarim Filali-Maltouf Mariem Sidatt Khattry Makhalla SidAhmed Dahdi Aly Cheybany Cheikh Ahmed Mohamed Val El-Mami Jacqueline E. Tate Umesh D. Parashar Mohammed Benhafid 《Vaccine》2019,37(11):1407-1411
Introduction
Rotavirus vaccine was introduced in Mauritania in December 2014. We investigated hospitalizations with diarrhea during pre and post-vaccination periods among children aged 0–5?years in Nouakchott, the capital of Mauritania.Methods
We conducted a retrospective review of hospital admission registries from November 1st 2012 through October 31th 2017 at all referral hospitals in Nouakchott. We described admissions of children aged 0–5?years by diagnosis, data of admission, age and sex, and compared the proportion of all childhood hospitalizations with diarrhea before and after rotavirus vaccine introduction.Results
In total, 6552 (19%) of all 34,329 hospitalizations in 0–5?year-olds had diarrhea. Of these, 3523/16,952 (20.7%) were recorded during the pre-vaccine period, 1373/6897 (19.9%) during the transition period (November 2014-October 2015), and 1656/10,480 (15.8%) during the post-vaccination period. The proportion of all childhood hospitalizations with diarrhea during the pre-vaccine period was 22.6% among males and 18.7% among females. Approximately one third (32.3%) of hospitalizations with diarrhea occurred in children aged 6–11?months. During the post-vaccination period, the proportion of hospitalizations with diarrhea declined by 24%, and the highest reduction (74%) was observed in children aged 2 to 5?years (P?<?0.001).Conclusions
The proportion of childhood hospitalizations with diarrhea in Nouakchott was reduced by about one fourth after introduction of rotavirus vaccination in Mauritania, indicating a major impact for public health for children in the capital city. 相似文献45.
Manish M. Patel Andrew D. Clark Roger I. Glass Harry Greenberg Jacqueline Tate Mathuram Santosham Colin F.B. Sanderson Duncan Steele Margaret Cortese Umesh D. Parashar 《Vaccine》2009
Introduction
Recently developed rotavirus vaccines have the potential to reduce diarrhea mortality in children in developing countries. Available data to date do not indicate risk of intussusception with these new vaccines. To avoid a potential unanticipated risk post-licensure, it is recommended that rotavirus immunization be initiated before 12 weeks of age when background intussusception rates are low. This policy could exclude a substantial number of children from vaccination, especially in developing countries where delays in vaccination are common.Methods
We conducted a scenario analysis to assess the potential benefits of mortality reduction from rotavirus versus the risk of fatal intussusception when the first dose of the vaccine is strictly administered by 12 weeks of age compared with a free strategy with vaccine administered before 1 year of age using data on rotavirus disease, vaccine safety and efficacy, and current diphtheria–tetanus–pertussis vaccination rates, and by incorporating hypothetical risks of intussusception.Results
In developing countries, assuming vaccine efficacy of 50% and 75% for doses 1 and 2, respectively, and a hypothetical sixfold and threefold increased relative risk of intussusception within 7 days of doses 1 and 2, respectively, initiating rotavirus immunization before 12 weeks of age would prevent 194,564 of the 517,959 annual rotavirus-associated deaths among children <5 years, while potentially resulting in 1106 fatal intussusception events. Administration of the first dose to infants up to 1 year of age would prevent an additional 54,087 rotavirus-associated deaths (total = 248,651) while potentially resulting in an additional 1226 intussusception deaths (total = 2332).Conclusion
In developing countries, the additional lives saved by broadening the age restrictions for initiation of rotavirus vaccination would far outnumber the hypothetical excess intussusception deaths that would accompany such an approach. 相似文献46.
Stephanie Donauer Daniel C. Payne Kathryn M. Edwards Peter G. Szilagyi Richard W. Hornung Geoffrey A. Weinberg James Chappell Caroline B. Hall Umesh D. Parashar Mary Allen Staat 《Vaccine》2013
The objective of this study is to determine the vaccine effectiveness (VE) of the pentavalent rotavirus vaccine (RV5) for preventing rotavirus-related hospitalizations and emergency department (ED) visits during the 2006–07 and 2007–08 rotavirus seasons using two study designs. Active, prospective population-based surveillance was conducted to identify cases of laboratory-confirmed rotavirus-related hospitalizations and ED visits to be used in case-cohort and case-control designs. VE was calculated using one comparison group for the case-cohort method and two comparison groups for the case-control method. The VE estimates produced by the three analyses were similar. Three doses of RV5 were effective for preventing rotavirus-related hospitalizations and ED visits in each analysis, with VE estimated as 92% in all three analyses. Two doses of RV5 were also effective, with VE ranging from 79% to 83%. A single dose was effective in the case-cohort analysis, but was not significant in either of the case-control analyses. The case-cohort and the case-control study designs produced the same VE point estimates for completion of the three dose series. Two and three doses of RV5 were effective in preventing rotavirus-related hospitalizations and ED visits. 相似文献
47.
Mamta Parashar SV Singh Jugal Kishore Ajay Kumar Milan Bhardwaj 《Indian Journal of Community Medicine》2013,38(1):42-48
Background:
Neonatal morbidity and mortality in India continue to be high. Among other reasons, newborn care practices are major contributors for such high rates.Objective:
To assess the effect of behavior change communication (BCC) package among pregnant women regarding neonatal care.Materials and Methods:
Semistructured and pretested schedule was used to interview 200 multigravidas on various aspects of neonatal care. Based on the preliminary data, BCC package was designed and implemented in intervention block in the community. Follow-up was done to find out change in their behavior.Statistical Analysis:
Data were analyzed using Epi info and Fischer exact test and chi-square test were applied in the baseline data. A P value of less than 0.05 was considered significant. Effect of the BCC package is given in terms of relative risk.Results:
BCC package increased 1.76 times higher number of deliveries conducted by trained dais in intervention group. There was significant improvement in using sterile cord tie (P = 0.01), applied nothing to the cord (P < 0.0001) and giving bath to their baby within 6 h of birth (P = 0.02) in intervention group as compared to nonintervention group. Significant difference was found between the two groups with regard to breastfeeding practices of baby. Harmful practices were reduced in the intervention group. Significant improvement was found in intervention group as compared to nonintervention group with regard to knowledge of danger signals, physiological variants, management of breastfeeding-related problems, and awareness of skin-to-skin technique for the management of hypothermic baby.Conclusion:
Inadequate knowledge and adverse practices regarding neonatal care among mothers in study areas were found. BCC package had favorable impact on behavior of mothers for neonatal care in intervention group. 相似文献48.
Marcelino Esparza-Aguilar Paul A Gasta?aduy Edgar Sánchez-Uribe Rishi Desai Umesh D Parashar Vesta Richardson Manish Patel 《Bulletin of the World Health Organization》2014,92(2):117-125
Objective
To assess, by socioeconomic setting, the effect of nationwide vaccination against species A rotavirus (RVA) on childhood diarrhoea-related hospitalizations in Mexico.Methods
Data on children younger than 5 years who were hospitalized for diarrhoea in health ministry hospitals between 1 January 2003 and 31 December 2011 were collected from monthly discharge reports. Human development indexes were used to categorize the states where hospitals were located as having generally high, intermediate or low socioeconomic status. Annual rates of hospitalization for diarrhoea – per 10 000 hospitalizations for any cause – were calculated. Administrative data were used to estimate vaccine coverage.Findings
In the states with high, intermediate and low socioeconomic status, coverage with a two-dose monovalent RVA vaccine – among children younger than 5 years – had reached 93%, 86% and 71%, respectively, by 2010. The corresponding median annual rates of hospitalization for diarrhoea – per 10 000 admissions – fell from 1001, 834 and 1033 in the “prevaccine” period of 2003–2006, to 597, 497 and 705 in the “postvaccine” period from 2008 to 2011, respectively. These decreases correspond to rate reductions of 40% (95% confidence interval, CI: 38–43), 41% (95% CI: 38–43) and 32% (95% CI: 29–34), respectively. Nationwide, RVA vaccination appeared to have averted approximately 16 500 hospitalizations for childhood diarrhoea in each year of the postvaccine period.Conclusion
Monovalent RVA vaccination has substantially reduced childhood diarrhoea-related hospitalizations for four continuous years in discretely different socioeconomic populations across Mexico. 相似文献49.
Michelle J Groome Sung-Sil Moon Daniel Velasquez Stephanie Jones Anthonet Koen Nadia van Niekerk Baoming Jiang Umesh D Parashar Shabir A Madhi 《Bulletin of the World Health Organization》2014,92(4):238-245
Objective
To investigate the effect of abstention from breastfeeding, for an hour before and after each vaccination, on the immune responses of infants to two doses of rotavirus vaccine.Methods
In Soweto, South Africa, mother–infant pairs who were uninfected with human immunodeficiency virus (HIV) were enrolled as they presented for the “6-week” immunizations of the infants. Each infant was randomly assigned to Group 1 – in which breastfeeding was deferred for at least 1 h before and after each dose of rotavirus vaccine – or Group 2 – in which unrestricted breastfeeding was encouraged. Enzyme-linked immunosorbent assays were used to evaluate the titres of rotavirus-specific IgA in samples of serum collected from each infant immediately before each vaccine dose and 1 month after the second dose. Among the infants, a fourfold or greater increase in titres of rotavirus-specific IgA following vaccination was considered indicative of seroconversion.Findings
The evaluable infants in Group 1 (n = 98) were similar to those in Group 2 (n = 106) in their baseline demographic characteristics and their pre-vaccination titres of anti-rotavirus IgA. After the second vaccine doses, geometric mean titres of anti-rotavirus IgA in the sera of Group-1 infants were similar to those in the sera of Group-2 infants (P = 0.685) and the frequency of seroconversion in the Group-1 infants was similar to that in the Group-2 infants (P = 0.485).Conclusion
Among HIV-uninfected South African infants, abstention from breastfeeding for at least 1 h before and after each vaccination dose had no significant effect on the infants’ immune response to a rotavirus vaccine. 相似文献50.
Mayank Bapna Bharat Parashar Vinod K. Sharma Lalit S. Chouhan 《Medicinal chemistry research》2012,21(7):1098-1106
Hydantoins have widely been used as antiarrythmic, anticonvulsant and antitumor agents but recent research has shown a different and novel cytotoxic activity of hydantoins and its derivatives, i.e. anti HIV, antibacterial and antifungal. The following research article deals with the synthesis of hydantoins and their derivatives by Mannich reaction viz., 3-(substituted)-5,5-diphenylimidazolidine-2,4-dione and 1-(substituted)-3,5,5-triphenylimidazolidine-2,4-dione. The synthesised compounds are novel and some of the compounds showed good antibacterial and antifungal activity equivalent to the standards used. All synthetic procedures were carried out in a microwave and not by conventional methods, which led to speedy process and high yield for the same. 相似文献