我国烟草品种工作的分析与思考

综述了我国育种工作近年取得的显著成绩和目前烟草品种工作中存在的问题,对此提出了加大品质育种及相关研究力度、加强对烟草育种工作的投入、改进品种的区域试验、增加区域试验和生产试验参试品种数量等建议。      

Dietary polyphenols against metabolic disorders: How far have we progressed in the understanding of the molecular mechanisms of action of these compounds?

The aim of this review was to critically assess the evidence supporting the metabolic and anti-inflammatory effects attributed to polyphenols and the potential mechanisms of action underlying these effects. The metabolic and anti-inflammatory properties of polyphenols and polyphenol-rich products have been shown mostly in rodents. These compounds appear to share multiple mechanisms of action at different body sites (gastrointestinal tract, microbiota, host organs) and the responsible molecules may be the original plant compounds, the microbial metabolites and (or) the host derived conjugates. Polyphenols may modify digestion and absorption of nutrients, microbiota composition and metabolism, and host tissue metabolic pathways but none of these mechanisms have been fully demonstrated in vivo and thus, more and better designed studies are needed. Furthermore, human clinical trials show inconsistent evidence of the metabolic and inflammation regulatory properties of polyphenols. Some of the principal limitations of these studies as well as recommendations to further progress in the understanding of the metabolic effects and mechanisms of action of polyphenols are discussed.     

Characteristics of a conditioned response in human subjects during extinction trials following a single traumatic conditioning trial.

A single experience of respiratory paralysis can be used to establish a conditioned response (CR) to a hitherto neutral stimulus. Respiratory paralysis to those undergoing it is horrific but not painful. The CR does not extinguish but becomes stronger as time passes despite repeated extinction trials. The skeletal aspects of the response are more variable than the autonomic aspects and do not provide any constant stimulus input. The results do not fit an "anxiety-reduction" explanation for the inextinguishability of traumatically conditioned responses but suggest that these responses have characteristics not mediated by reinforcement. (20 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Blinding controlled-release tablets for clinical trials

The objective of the current study was to develop a method to blind commercially available Wellbutrin® SR 150 mg sustained-release tablets for a clinical study. Overcoating was selected as the most appropriate blinding method. Hydroxypropyl methylcellulose (Opadry® II) containing red iron oxide and titanium dioxide was applied to the Wellbutrin tablets at coating levels ranging from 0.5% to 4% weight gain. When compared against the uncoated product, no significant differences in drug release were noted over an 8-hr period. Matching placebo tablets, prepared using specially designed tablet tooling, were coated with the same cellulosic polymer that was used for the active. The coated active and placebo tablets were virtually indistinguishable. To test the applicability of this overcoating technique for blinding other controlled release products, the same procedure was used to coat Glucotrol® XL 5 mg tablets and Theo-Dur 200 mg tablets. The debossing on the Theo-Dur tablets and the laser-drilled hole on the surface of the Glucotrol tablets prevented blinding. The Theo-Dur tablets were mechanically weak and not able to withstand the coating process. Dissolution testing revealed significantly higher amounts of drug were released from the blinded Glucotrol tablets compared to the unblinded product at the 12 hr time point. The findings from this study suggest that overcoating with pigmented hydroxypropyl methylcellulose may not be useful for blinding all controlled-release tablets.     

Promising Biomarkers in Head and Neck Cancer: The Most Clinically Important miRNAs

Head and neck cancers (HNCs) comprise a heterogeneous group of tumors that extend from the oral cavity to the upper gastrointestinal tract. The principal etiologic factors for oral tumors include tobacco smoking and alcohol consumption, while human papillomavirus (HPV) infections have been accused of a high incidence of pharyngeal tumors. Accordingly, HPV detection has been extensively used to categorize carcinomas of the head and neck. The diverse nature of HNC highlights the necessity for novel, sensitive, and precise biomarkers for the prompt diagnosis of the disease, its successful monitoring, and the timely prognosis of patient clinical outcomes. In this context, the identification of certain microRNAs (miRNAs) and/or the detection of alterations in their expression patterns, in a variety of somatic fluids and tissues, could serve as valuable biomarkers for precision oncology. In the present review, we summarize some of the most frequently studied miRNAs (including miR-21, -375, -99, -34a, -200, -31, -125a/b, -196a/b, -9, -181a, -155, -146a, -23a, -16, -29, and let-7), their role as biomarkers, and their implication in HNC pathogenesis. Moreover, we designate the potential of given miRNAs and miRNA signatures as novel diagnostic and prognostic tools for successful patient stratification. Finally, we discuss the currently ongoing clinical trials that aim to identify the diagnostic, prognostic, or therapeutic utility of miRNAs in HNC.     

Designing consumer trials balanced for first and higher orders of carry-over effect when only a subset of k samples from t may be tested

The problem of balancing out carry-over effects of preceding samples in consumer trials when each consumer only receives k out of a possible t products is discussed. For large trials an all-possible-combinations approach can balance all higher order effects. Mutually orthogonal latin squares can achieve this with much smaller numbers of consumers when t is a prime number or an integer power of a prime. In general subsets-designs balanced just for first-order carry-over may easily be constructed either by unfolding a full design or by combining them with incomplete block designs. Tables of designs from 4 to 11 products are given, general methods are described that give routes to designs with higher numbers of samples.     

一种基于Mean Shift和Kalman预测的带宽自适应跟踪算法

Mean Shift算法是视觉监控领域广泛应用的经典目标跟踪方法,但对于速度过快或尺度变化大的目标的跟踪存在较大的缺陷。针对这一问题,提出了一种基于Mean Shift和Kalman方法预测的带宽自适应跟踪算法。该算法提出以Kalman预测目标在下帧中的位置作为Mean Shift迭代初始位置,以高效锁定各类运动目标;同时采用增量试探法自动调节带宽以适应目标的尺度变化。通过对行人和车辆等不同监控对象的实验表明,该跟踪算法具有良好的鲁棒性。     

Advantages and Disadvantages of Different Treatment Methods in Achondroplasia: A Review

Achondroplasia (ACH) is a disease caused by a missense mutation in the FGFR3 (fibroblast growth factor receptor 3) gene, which is the most common cause of short stature in humans. The treatment of ACH is necessary and urgent because untreated achondroplasia has many complications, both orthopedic and neurological, which ultimately lead to disability. This review presents the current and potential pharmacological treatments for achondroplasia, highlighting the advantages and disadvantages of all the drugs that have been demonstrated in human and animal studies in different stages of clinical trials. The article includes the potential impacts of drugs on achondroplasia symptoms other than short stature, including their effects on spinal canal stenosis, the narrowing of the foramen magnum and the proportionality of body structure. Addressing these effects could significantly improve the quality of life of patients, possibly reducing the frequency and necessity of hospitalization and painful surgical procedures, which are currently the only therapeutic options used. The criteria for a good drug for achondroplasia are best met by recombinant human growth hormone at present and will potentially be met by vosoritide in the future, while the rest of the drugs are in the early stages of clinical trials.     

Hydroxycinnamic acids and human health: recent advances

There is an urgent need to improve human diet globally. Compelling evidence gathered over the past several decades suggests that a suboptimal diet is associated with many chronic diseases and may be responsible for more deaths than any other risks worldwide. The main components in our diet that need higher intake are whole grains, fruit and vegetables, and nuts and seeds; all of these are important sources of dietary fiber and polyphenols. The health benefits of dietary fiber and polyphenols are also supported by several decades of valuable research. However, the conclusions drawn from interventional human trials are not straightforward and the action mechanisms in improving human health are not fully understood. Moreover, there is a great inter-individual variation caused by different individual capabilities of processing, absorbing and using these compounds effectively. Data on the bioavailability and bioefficacy of hydroxycinnamic acids (HCAs) are limited when compared to other classes of polyphenols (e.g. anthocyanins). This review aims to summarize the latest research advances related to HCA bioavailability and their biological effects revealed by epidemiological data, pre-clinical and clinical studies. Moreover, we aim to review the effects of HCAs on gut microbiota diversity and function and its respective influence on host health. © 2019 Society of Chemical Industry