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1.
Farzad Mostashari Annie Fine Debjani Das John Adams Marcelle Layton 《Journal of urban health》2003,80(1):i43-i49
In 1998, the New York City Department of Health and the Mayor’s Office of Emergency Management began monitoring the volume of ambulance dispatch calls as a surveillance tool for biologic terrorism. We adapted statistical techniques designed to measure excess influenza mortality and applied them to outbreak detection using ambulance dispatch data. Since 1999, we have been performing serial daily regressions to determine the alarm threshold for the current day. In this article, we evaluate this approach by simulating a series of 2,200 daily regressions. In the influenza detection implementation of this model, there were 71 (3.2%) alarms at the 99% level. Of these alarms, 64 (90%) occurred shortly before or during a period of peak influenza in each of six influenza seasons. In the bioterrorism detection implementation of this methodology, after accounting for current influenza activity, there were 24 (1.1%) alarms at the 99% level. Two occurred during a large snowstorm, 1 is unexplained, and 21 occurred shortly before or during a period of peak influenza activity in each of six influenza seasons. Our findings suggest that this surveillance system is sensitive to communitywide respiratory outbreaks with relatively few false alarms. More work needs to be done to evaluate the sensitivity of this approach for detecting nonrespiratory illness and more localized outbreaks. 相似文献
2.
Thomas A. Krenitsky John Dillberger Elena Zotova Joseph C. Arezzo James B. Koprich Farzad Mortazavi Timothy A. Gates Gary L. Dunbar 《Drug development research》2004,62(1):60-70
In cultured cells, KP544 [2‐amino‐5‐(4‐chlorophenylethynyl)‐4‐(4‐trans‐hydroxycyclohexyl amino) pyrimidine] amplifies differentiation initiated by nerve growth factor (NGF) or cAMP. This report describes the pharmacokinetics, safety, and neuroprotective efficacy of KP544 in rats. After an oral dose of 10 mg/kg KP544 was 25% bioavailable with a plasma half‐life of 1.3 h and brain levels 6‐fold higher than plasma levels at 4 and 8 h post‐dose. In a safety study, daily oral dosing for 30 days at 10 and 100 mg/kg was well tolerated. The favorable pharmacokinetic and safety profiles, together with its amplification of NGF in vitro, prompted evaluation of KP544 in two models involving NGF deficiencies. In the first model, brains were lesioned with intrastriatal injections of quinolinic acid. KP544 at oral doses of 0.02 to 1.0 mg/kg/day almost completely prevented the resulting learning deficits as evaluated using a radial‐arm‐water maze. At the lowest dose, there was a slower onset of functional improvement. These effects were accompanied by reductions (16–34%) in the striatal lesion size that were greatest at the highest dose and comparable to those seen with NGF therapy. The second model involved a peripheral neuropathy induced by taxol that is associated with decreases in NGF. KP544 at oral doses of 0.1–10 mg/kg/day decreased the severity of the neuropathy as measured by caudal nerve conduction velocities (30–70% return to control values). In both models, KP544 had a large therapeutic index suggesting its potential as a new approach for treating clinical disorders involving deficiencies in NGF. Drug Dev. Res. 62:60–70, 2004. © 2004 Wiley‐Liss, Inc. 相似文献
3.
Smoking practices in New York City: The use of a population-based survey to guide policy-making and programming 总被引:4,自引:0,他引:4
Farzad Mostashari Bonnie D. Kerker Anjum Hajat Nancy Miller Thomas R. Frieden 《Journal of urban health》2005,82(1):58-70
To inform New York City’s (NYC’s) tobacco control program, we identified the neighborhoods with the highest smoking rates,
estimated the burden of second-band smoke exposure, assessed the early response to state taxation, and examined cessation
practices. We used a stratified random design to conduct a digit-dialed telephone survey in 2002 among 9,674 New York City
adults. Our main outcome measures included prevalence of cigarette smoking, exposure to second-hand smoke, the response of
smokers to state tax increases, and cessation practices. Even after controlling for sociodemographic factors (age, racelethnicity,
income, education, marital status, employment status, and foreign-born status) smoking rates were highest in Central Harlem
and in the South Bronx. Sixteen percent of nonsmokers reported frequent exposure to second-hand smoke at home or in a workplace.
Among smokers with a child with asthma, only 33% reported having a no-smoking policy in their homes. More than one fifth of
smokers reported reducing the number of cigarettes they smoked in response to the state tax increase. Of current smokers who
tried to quit, 65% used no cessation aid. These data were used to inform New York City’s smoke-free legislation, taxation,
public education, and a free nicotine patch give-away program. In conclusion, large, local surveys can provide essential data
to effectively advocate for, plan, implement, and evaluate a comprehensive tobacco control program.
Dr. Mostashari (the guarantor) made substantial contributions to the conception, design, and supervision of this paper, the
analysis and interpretation of data, the drafting of the paper, critical revisions of the paper for important intellectual
content, and the acquisition of data and funding for this research. Dr. Kerker made substantial contributions to the analysis
and interpretation of data, the drafting of the paper and critical revisions of the paper for important intellectual content.
Ms. Hajat made substantial contributions to the acquisition of data and critical revisions of the paper for important intellectual
content. Dr. Miller made substantial contributions to the conception of this paper and critical revisions of the paper for
important intellectual content. Dr. Frieden made substantial contributions to the conception, design, and supervision of this
paper and critical revisions of the paper for important intellectual content. 相似文献
4.
5.
The aim of this study is to determine safe fasting plasma glucose (FPG) levels. We included data on 5,960 individuals aged ≥20?years at baseline with at least one follow-up examination. Diabetes was ascertained in accordance with American Diabetes Association criteria, using standard 2-h post-challenge plasma glucose test. Multivariate restricted cubic splines Weibull regression was implemented for interval-censored survival data on incident diabetes. We used Harrell’s C statistic for discrimination, Nam-D’Agostino χ2 for calibration, and Royston’s R 2 for variations in the outcome explained by models. During a 6-year median follow-up, 369 incident cases of diabetes were ascertained. Family history of diabetes, systolic blood pressure, waist-to-height ratio, and triglyceride-to-high-density lipoprotein cholesterol ratio, independent of FPG and each other remained associated with incident diabetes. The cubic splines model achieved good calibration (χ2?=?12.1) and discrimination (C?=?0.828) and explained 75% of variation in the time until incident diabetes. A J-shaped FPG-diabetes relationship was observed. Descending arm of the dose–response relationship curve corresponded to increasing FPG levels up to 4.0?mmol?l?1, where it started increasing. The risk of incident diabetes decreased with decreasing levels of FPG down to 4.0?mmol?l?1, where the risk stopped decreasing. Multivariate-adjusted risk of incident diabetes was zero at FPG?=?5.05?mmol?l?1. Although currently there is no firm evidence to show that early intervention among individuals with the elevated FPG levels could prevent or delay onset of diabetes, individuals with FPG levels below 5.05?mmol?l?1 could be safely reassured about their near-term risk of developing incident diabetes and screened on a less frequent basis. 相似文献
6.
Fatemeh GHAFFARIFAR Farzad ESAVAND HEYDARI Abdolhosein DALIMI Zuhair M. HASSAN Mahdi DELAVARI Hajar MIKAEILOO 《Iranian Journal of Parasitology》2015,10(2):258-267
Background:
In leishmaniasis, some drugs prescribed for treatment have toxic effects and there are reports about drug resistance in some countries. Due to this fact, using herbal drugs such as artemisinin with good efficacy and low toxic effect might be suitable.Methods:
We evaluated the apoptotic effect of artemisinin on Leishmania major in vitro and the antileishmanial activities of artemisinin on leishmaniasis in BALB/c mice and at the end INF-γ and IL-4 cytokines levels were detected by ELISA in spleen cell culture supernatants. During treatment the lesion size and survival rate were measured each four and ten days, respectively.Results:
Percentage of early and late apoptosis in promastigotes of control group and promastigotes treated with 10, 25, 50 and 100 μg/ml of artemisinin after 48 h were 0.13, 16.04, 41.23, 49.03 and 81.83, respectively. The IFN-γ in ointment treated group were higher than those of other groups (P<0.05). The in vivo results showed that ointment compounds healed the lesions more effectively rather than intraperitoneal injection method (P<0.05). The survival rate of mice 150 days after challenge in treated group with ointment of artemisinin was 66% while all mice in control groups were died.Conclusion:
All of in vitro results represented that this drug had antileishmanial effects and these results were confirmed by evaluation effects in vivo condition of leishmaniasis. Interestingly, according to these results it can be concluded that this drug has antileishmanial effects in vitro and in vivo conditions. Artemisinin induces cytotoxic effect on L. major via apoptosis-related mechanism. 相似文献7.
Alireza Oraii Ali Vasheghani-Farahani Saeed Oraii Pegah Roayaei Pargol Balali Farzad Masoudkabir 《Revista portuguesa de cardiologia》2021,40(7):509-518
Atrial fibrillation is the most common arrhythmia in adults and its prevalence is growing rapidly. It has been shown that AF is associated with increased risk of heart failure, ischemic and hemorrhagic stroke, and mortality. Hence, there is growing interest among researchers in seeking preventive and therapeutic interventions regarding AF. In recent decades, it has been suggested that statins may decrease the incidence of AF and may also decrease its recurrence after cardioversion and catheter ablation. These effects are thought to be mediated by different mechanisms such as modulating inflammation, altering the properties of transmembrane ion channels, interfering with activation of matrix metalloproteinases, and acting on endothelial function. In this article, we review and update current knowledge about the role of statins in primary and secondary prevention of AF in general and specific populations. 相似文献
8.
9.
The use of fibers in cementitious composites yields numerous benefits due to their fiber-bridging capabilities in resisting cracks. Therefore, this study aimed to improve the shear-resisting capabilities of conventional concrete through the hybridization of multiple synthetic fibers, specifically on reinforced concrete structures in seismic-prone regions. For this study, 16 hybrid fiber-reinforced concretes (HyFRC) were developed from the different combinations of Ferro macro-synthetic fibers with the Ultra-Net, Super-Net, Econo-Net, and Nylo-Mono microfibers. These hybrids were tested under direct shear, resulting in improved shear strength of controlled specimens by Ferro-Ultra (32%), Ferro-Super (24%), Ferro-Econo (44%), and Ferro-Nylo (24%). Shear energy was further assessed to comprehend the effectiveness of the fiber interactions according to the mechanical properties, dosage, bonding power, manufactured material, and form of fibers. Conclusively, all fiber combinations used in this study produced positive synergistic effects under direct shear at large crack deformations. 相似文献
10.
Ali Falaki Farzad Towhidkhah Tao Zhou Mark L. Latash 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2014,232(11):3645-3658
We used robot-generated perturbations applied during position-holding tasks to explore stability of induced unintentional movements in a multidimensional space of muscle activations. Healthy subjects held the handle of a robot against a constant bias force and were instructed not to interfere with hand movements produced by changes in the external force. Transient force changes were applied leading to handle displacement away from the initial position and then back toward the initial position. Intertrial variance in the space of muscle modes (eigenvectors in the muscle activations space) was quantified within two subspaces, corresponding to unchanged handle coordinate and to changes in the handle coordinate. Most variance was confined to the former subspace in each of the three phases of movement, the initial steady state, the intermediate position, and the final steady state. The same result was found when the changes in muscle activation were analyzed between the initial and final steady states. Changes in the dwell time between the perturbation force application and removal led to different final hand locations undershooting the initial position. The magnitude of the undershot scaled with the dwell time, while the structure of variance in the muscle activation space did not depend on the dwell time. We conclude that stability of the hand coordinate is ensured during both intentional and unintentional actions via similar mechanisms. Relative equifinality in the external space after transient perturbations may be associated with varying states in the redundant space of muscle activations. The results fit a hierarchical scheme for the control of voluntary movements with referent configurations and redundant mapping between the levels of the hierarchy. 相似文献