中国岩黄芪属(豆科)植物资料增补

根据对标本的研究及文献资料的整理,证实了西伯利亚岩黄芪在中国的分布;山竹岩黄芪在新疆的分布新记录。另外,还报道了地中海岩黄芪在陕西的栽培记录。     

内蒙古植被枯黄期变化及其与气候和植被生产力的关系

基于2001—2018年MODIS NDVI数据,采用累计归一化植被指数(NDVI)的Logistic曲线曲率极值法,识别内蒙古植被枯黄期及其时空变化特征,并在生态区尺度上分析枯黄期对气候因子和NDVI的响应特征。结果表明: 研究期间,内蒙古植被平均枯黄期主要集中在第260～280天。森林生态区枯黄期为第270～280天,从南向北推迟;草原生态区枯黄期最早,介于第257～273天,从东北向西南逐渐推迟;荒漠生态区枯黄期为第270～283天,东北向西南呈推迟态势。2001—2018年间,3个生态区植被枯黄期均呈不显著推迟趋势。植被生产力从东北向西南逐渐降低,在时间上呈增加趋势的面积大于呈减小趋势的面积。全内蒙古和各生态区植被枯黄期受季前2～3个月降水量的正面影响较大,与季前平均温度、最高温度和最低温度均呈正相关关系。全内蒙古和各生态区,8和9月植被生产力的增加(或减少)将推迟(或提前)植被枯黄期,而6和7月植被生产力的增加(或减少)将提前(或推迟)草原和荒漠生态区植被枯黄期。     

Therapeutic opportunities of edible antiviral plants for COVID-19

Molecular and Cellular Biochemistry - The pandemic of Serious Acute Respiratory Syndrome Corona Virus-2 (SARS-CoV-2) that produces corona virus disease (COVID-19) has challenged the entire mankind...     

叶绿素结合蛋白CP24介导光照响应基因StRSM 1调控叶绿素积累

单MYB转录因子成员RSM(RADIALIS-like SANT/MYB)突变,倒置黑暗诱导的叶绿素减少,原因有待确定;为了揭示RSM如何调控叶绿素积累,本研究运用基因工程途径,获得了普通烟草和马铃薯体内抑制和过量表达StRSM 1阳性转化株系,测定了阳性转化株系的叶绿素积累等生理表型;结果显示,普通烟草和马铃薯体内抑制RSM 1表达,显著增加了叶绿素积累,叶色随之加深;RSM 1过量表达,显著减少叶绿素积累,叶色变浅。叶绿素代谢相关基因表达测定结果显示,StRSM 1过量表达增加了黑暗下叶绿素结合蛋白CP24基因的表达,改变了其表达模式。以上结果表明,转录因子StRSM 1响应光照反向调控叶绿素积累,叶绿素结合蛋白CP24参与了StRSM 1对叶绿素积累的调控。结果有助于进一步明确RSM 1如何响应光照和深刻理解RSM 1参与的光照响应。     

Establishment and characterization of permanent cell line from gill tissue of Labeo rohita (Hamilton) and its application in gene expression and toxicology

Rohu gill cell line (LRG) was established from gill tissue of Indian major carp (Labeo rohita), a freshwater fish cultivated in India. The cell line was maintained in Leibovitz's L-15 supplemented with 10 % foetal bovine serum (FBS). This cell line has been sub-cultured more than 85 passages over a period of 2 years. The LRG cell line consists of both epithelial and fibroblastic-like cells. The cells were able to grow at a wide range of temperatures from 22 to 32 °C, the optimum temperature being 28 °C. The growth rate of gill cells increased as the FBS proportion increased from 2 to 20 % at 28 °C. The plating efficiency was also high (34.37 %). The viability of the LRG cell line was 70–80 % after 6 months of storage in liquid nitrogen. The karyotype analysis revealed a diploid count of 50 chromosomes. The gill cells of rohu were successfully transfected with pEGFP-N1. Amplification of mitochondrial Cox1 gene using primers specific to L. rohita confirmed the origin of this cell line from L. rohita. The cytotoxicity of malathion was assessed in LRG cell line using multiple endpoints such as 3-(4, 5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide, Neutral Red assay, Alamar Blue assay and Coomassie Blue protein assay. Acute toxicity assay on fish was conducted by exposing L. rohita for 96 h to malathion under static conditions. Statistical analysis revealed good correlation with r ²?=?0.946–0.990 for all combinations between endpoints employed. Linear correlations between each in vitro effective concentration 50 and the in vivo lethal concentration 50 data were highly significant.     

Synthesis and biological evaluation of amino analogs of Ludartin: Potent and selective cytotoxic agents

Diverse amino analogs of Ludartin, a cytotoxic guaianolide and a position isomer of an anticancer drug, Arglabin were prepared through Michael type addition at its highly active α-methylene-γ-lactone motif. The semisynthetic derivatives were subjected to sulphorhodamine B cytotoxicity assay against a panel of four different human cancer cell lines viz. lung (A-549), leukemia (THP-1), prostate (PC-3) and colon (HCT-116) to look into structure–activity relationship. Few of the analogs displayed potent selective cytotoxicity compared to the parent molecule-Ludartin (1). (11R)-13-(Diethyl amine)-11,13-dihydroludartin (6) and (11R)-13-(piperidine)-11,13-dihydroludartin (10) showed almost same cytotoxicity against leukemia cell lines (THP-1) as that of parent molecule-Ludartin, but were more active against colon (HCT-116) cancer cells. (11R)-13-(Morpholine)-11,13-dihydroludartin (11) displayed selectively better cytotoxicity against Leukemia cancer cells (THP-1) exhibiting IC₅₀ of 2.8 μM. (11R)-13-(6-Nitroindazole)-11,13-dihydroludartin (17) was four times more potent than Ludartin with selective cytotoxic effects against prostate cancer cells (2.2 μM) while as (11R)-13-(6-nitroindazole)-11,13-dihydroludartin (18) exhibited three-fold selective cytotoxicity for Lung (A-549) cancer cell lines exhibiting IC₅₀ of 2.6 μM.     

Using microwave irradiation in Marchi's method for demonstrating degenerated myelin

Conventional methods for histological preparation of degenerated myelin are time-consuming and difficult. The purpose of our study was to shorten the time required for the procedure and to obtain better quality results for light microscopic demonstration of degenerated myelin in the central and peripheral nervous systems by using microwave irradiation. Rat brain and sciatic nerve were used for the study. The middle cerebral artery was occluded and the sciatic nerve was cut to produce myelin degeneration. Marchi's method was used for staining degenerated myelin. Fixation for light microscopy that would take two days using the conventional procedure was completed in 16.5–18.5 min using microwave irradiation. While staining of degenerated myelin requires 10 days for the conventional Marchi method, we decreased it to 7 h for brain tissue and 1 h for sciatic nerve by using the microwave oven. Moreover, a better quality preparation was achieved in the groups stained under microwave irradiation than those prepared by the conventional method.     

Association of practice size and pay-for-performance incentives with the quality of diabetes management in primary care

Background:

Not enough is known about the association between practice size and clinical outcomes in primary care. We examined this association between 1997 and 2005, in addition to the impact of the Quality and Outcomes Framework, a pay-for-performance incentive scheme introduced in the United Kingdom in 2004, on diabetes management.

Methods:

We conducted a retrospective open-cohort study using data from the General Practice Research Database. We enrolled 422 general practices providing care for 154 945 patients with diabetes. Our primary outcome measures were the achievement of national treatment targets for blood pressure, glycated hemoglobin (HbA_1c) levels and total cholesterol.

Results:

We saw improvements in the recording of process of care measures, prescribing and achieving intermediate outcomes in all practice sizes during the study period. We saw improvement in reaching national targets after the introduction of the Quality and Outcomes Framework. These improvements significantly exceeded the underlying trends in all practice sizes for achieving targets for cholesterol level and blood pressure, but not for HbA_1c level. In 1997 and 2005, there were no significant differences between the smallest and largest practices in achieving targets for blood pressure (1997 odds ratio [OR] 0.98, 95% confidence interval [CI] 0.82 to 1.16; 2005 OR 0.92, 95% CI 0.80 to 1.06 in 2005), cholesterol level (1997 OR 0.94, 95% CI 0.76 to 1.16; 2005 OR 1.1, 95% CI 0.97 to 1.40) and glycated hemoglobin level (1997 OR 0.79, 95% CI 0.55 to 1.14; 2005 OR 1.05, 95% CI 0.93 to 1.19).

Interpretation:

We found no evidence that size of practice is associated with the quality of diabetes management in primary care. Pay-for-performance programs appear to benefit both large and small practices to a similar extent.There is a well-established body of literature showing positive associations between volume of patients and clinical outcomes in health care, which has been documented by a systematic review.¹ However, this association has usually been examined in a limited number of discrete procedures, and most studies have involved hospital-based services rather than primary care settings.^2–5Improving our understanding of the association between volume of patients and outcomes in primary care is important for several reasons. First, most contacts with health systems occur in primary care settings, and optimizing the delivery of these services has the potential to improve the health of the population.⁶ Second, over the past decade, primary care has assumed greater responsibility for managing the growing burden of chronic disease.^7,8 Larger providers may be better resourced, through the employment of additional support staff and greater use of information technology, to deliver the systematic, structured care necessary for the effective management of chronic disease.^6,9 Third, larger providers may have been more responsive to nonfinancial and financial incentives, including pay for performance, implemented by payers aimed at improving the quality of care.^7,10 Fourth, in many countries, primary care is based around a predominance of small practices.^6,11,12 In 2006, 53% of practices in England and Wales had three or fewer family physicians.¹¹ In the same year in the United States, 30.3% of family physicians were in solo practice; 9.4% were in two-physician practices.¹²Despite the limited data available, concerns have been raised about the standards of care delivered by smaller family practices.¹³ In the United Kingdom and Canada, this has resulted in an explicit policy objective of encouraging smaller practices to amalgamate.^13,14Our study examines the associations between the size of practice and the quality of diabetes management in UK primary care settings between 1997 and 2005. We tested the hypotheses that patients attending larger family practices receive better care for diabetes and that the quality gap between larger and smaller practices has increased over the past decade. We also hypothesized that larger practices derived more benefit from the Quality and Outcomes Framework, a major pay-for-performance program in primary care introduced in 2004.     

动态分析沙鼠非酒精性脂肪肝病形成及生化影响

目的分析高脂饮食导致的沙鼠NAFLD疾病进展中脂质代谢、肝功能、抗氧化等方面的变化,探讨沙鼠NAFLD的形成机理。方法雄性沙鼠120只,随机分为对照组和模型组。对照组给予普通饲料,模型组高脂饮食建立NAFLD模型。分别于1、2、4、6、8、16周每组各处死10只动物,观察肝脏病理变化,计算肝指数,检测血清CHO、TG、LDL-C、HDL-C、GOP、GPT及肝组织的SOD、GSH-PX、CAT活性和FFA含量。结果模型组病理观察2周形成单纯性脂肪肝,6周动物门管区有轻度炎症,8周出现腺泡Ⅲ带局灶性窦周/细胞周纤维化,16周肝脏中度纤维化;模型组第1、2、4、6、8、16周时CHO、HDL-C、LDL-C及FAA波动性升高,但均高于同期对照组（P〈0.05,P〈0.01）,TG在1、2、4周高于同期对照组（P〈0.05,P〈0.01）;16周末GOT、GPT出现了显著性升高（P〈0.01）。抗氧化酶GSH-PX、CAT、SOD活性模型组在第8～16周显著性降低（P〈0.05,P〈0.01）。结论高脂饮食使沙鼠2周形成单纯性脂肪肝模型后,随饲喂时间延长,16周末可发展为中度肝纤维化。脂质代谢紊乱与氧化应激在沙鼠NAFLD进展中的发挥了不同的作用。     

Correction to: Energy Plasmon Modes in Metamaterial‑Filled Double‑Layer Graphene‑Wrapped Cylindrical Waveguides

Plasmonics - Correction to: Plasmonics