雪荔颗粒喷雾干燥法制备的工艺优化

采用正交试验法，选定药液密度、进液速度和进风温度3因素，筛选雪荔颗粒喷雾干燥的最佳工艺。最佳工艺为药液密度1．07mg／ml(热测法)，进液速度9ml／min，进风温度176℃。     

Dementia studies in Chinese populations

Variations in the prevalence of dementia in different ethnic groups have been reported worldwide, and a number of reviews have provided a picture of epidemiological studies in dementia research. However, little is known about epidemiological studies in Chinese populations. In this review, we searched PubMed and the Web of Science for original research articles published in English up to July 2013 on the prevalence, incidence, risk factors, and prognosis of dementia in Chinese populations worldwide. Except for the prevalence, we included only population-based follow-up studies. We identified 25 studies in elderly Chinese residents in Mainland China, Hong Kong, Taiwan, and Singapore, and found a higher prevalence of dementia in Mainland China than in the other locations, which may be due to that the studies from Mainland China are more recent than those from other locations. A notable increase in incidence was observed when dementia cases were diagnosed using 10/66 diagnostic criteria compared to other criteria. Studies on risk factors for dementia were limited and mostly from Mainland China. Age, gender, education, smoking, and alcohol consumption were related to the risk of dementia in Chinese populations. Only two prognostic studies were identified, and age, gender, and residential area were related to the prognosis of dementia. In conclusion, the prevalence, incidence, and risk factors for dementia found in Chinese populations were comparable to other ethnic groups, but no conclusive results on prognosis were found. The differences in prevalence and incidence were influenced by the diagnostic criteria and the time of study. Longitudinal population-based studies on the incidence, risk factors, and prognosis of dementia in Chinese populations are required.     

血小板衍化生长因子B在糖尿病大鼠肾皮质中的表达

本研究以半定量RT-PCR法测定了糖尿病及对照Wistar大鼠肾皮质血小板衍化生长因子B(PDGFB)mRNA水平,发现糖尿病大鼠为对照组2.5倍,提示PDGFB在糖尿病肾病中起一定作用。     

Repetitive transcranial magnetic stimulation for lower extremity motor function in patients with stroke: a systematic review and network meta-analysis

Transcranial magnetic stimulation, a type of noninvasive brain stimulation, has become an ancillary therapy for motor function rehabilitation. Most previous studies have focused on the effects of repetitive transcranial magnetic stimulation(rTMS) on motor function in stroke patients. There have been relatively few studies on the effects of different modalities of rTMS on lower extremity motor function and corticospinal excitability in patients with stroke. The MEDLINE, Embase, Cochrane Library, ISI Science Citation Index, Physiotherapy Evidence Database, China National Knowledge Infrastructure Library, and ClinicalTrials.gov databases were searched. Parallel or crossover randomized controlled trials that addressed the effectiveness of rTMS in patients with stroke, published from inception to November 28, 2019, were included. Standard pairwise meta-analysis was conducted using R version 3.6.1 with the "meta" package. Bayesian network analysis using the Markov chain Monte Carlo algorithm was conducted to investigate the effectiveness of different rTMS protocol interventions. Network meta-analysis results of 18 randomized controlled trials regarding lower extremity motor function recovery revealed that low-frequency rTMS had better efficacy in promoting lower extremity motor function recovery than sham stimulation. Network meta-analysis results of five randomized controlled trials demonstrated that highfrequency rTMS led to higher amplitudes of motor evoked potentials than low-frequency r TMS or sham stimulation. These findings suggest that rTMS can improve motor function in patients with stroke, and that low-frequency rTMS mainly affects motor function, whereas high-frequency rTMS increases the amplitudes of motor evoked potentials. More highquality randomized controlled trials are needed to validate this conclusion. The work was registered in PROSPERO(registration No. CRD42020147055) on April 28, 2020.     

Widespread spatial integration in primary somatosensory cortex

Tactile discrimination depends on integration of information from the discrete receptive fields (RFs) of peripheral sensory afferents. Because this information is processed over a hierarchy of subcortical nuclei and cortical areas, the integration likely occurs at multiple levels. The current study presents results indicating that neurons across most of the extent of the hand representation in monkey primary somatosensory cortex (area 3b) interact, even when these neurons have separate RFs. We obtained simultaneous recordings by using a 100-electrode array implanted in the hand representation of primary somatosensory cortex of two anesthetized owl monkeys. During a series of 0.5-s skin indentations with single or dual probes, the distance between electrodes from which neurons with synchronized spike times were recorded exceeded 2 mm. The results provide evidence that stimuli on different parts of the hand influence the degree of synchronous firing among a large population of neurons. Because spike synchrony potentiates the activation of commonly targeted neurons, synchronous neural activity in primary somatosensory cortex can contribute to discrimination of complex tactile stimuli.     

All-trans retinoic acid regulates hepatic bile acid homeostasis

Retinoic acid (RA) and bile acids share common roles in regulating lipid homeostasis and insulin sensitivity. In addition, the receptor for RA (retinoid x receptor) is a permissive partner of the receptor for bile acids, farnesoid x receptor (FXR/NR1H4). Thus, RA can activate the FXR-mediated pathway as well. The current study was designed to understand the effect of all-trans RA on bile acid homeostasis. Mice were fed an all-trans RA-supplemented diet and the expression of 46 genes that participate in regulating bile acid homeostasis was studied. The data showed that all-trans RA has a profound effect in regulating genes involved in synthesis and transport of bile acids. All-trans RA treatment reduced the gene expression levels of Cyp7a1, Cyp8b1, and Akr1d1, which are involved in bile acid synthesis. All-trans RA also decreased the hepatic mRNA levels of Lrh-1 (Nr5a2) and Hnf4α (Nr2a1), which positively regulate the gene expression of Cyp7a1 and Cyp8b1. Moreover, all-trans RA induced the gene expression levels of negative regulators of bile acid synthesis including hepatic Fgfr4, Fxr, and Shp (Nr0b2) as well as ileal Fgf15. All-trans RA also decreased the expression of Abcb11 and Slc51b, which have a role in bile acid transport. Consistently, all-trans RA reduced hepatic bile acid levels and the ratio of CA/CDCA, as demonstrated by liquid chromatography-mass spectrometry. The data suggest that all-trans RA-induced SHP may contribute to the inhibition of CYP7A1 and CYP8B1, which in turn reduces bile acid synthesis and affects lipid absorption in the gastrointestinal tract.     

Retinoic acid regulates cell cycle genes and accelerates normal mouse liver regeneration

All-trans retinoic acid (RA) is a potent inducer of regeneration. Because the liver is the principal site for storage and bioactivation of vitamin A, the current study examines the effect of RA in mouse hepatocyte proliferation and liver regeneration. Mice that received a single dose of RA (25 μg/g) by oral gavage developed hepatomegaly with increased number of Ki67-positive cells and induced expression of cell cycle genes in the liver. DNA binding data revealed that RA receptors retinoic acid receptor β (RARβ) and retinoid x receptor α (RXRα) bound to cell cycle genes Cdk1, Cdk2, Cyclin B, Cyclin E, and Cdc25a in mice with and without RA treatment. In addition, RA treatment induced novel binding of RARβ/RXRα to Cdk1, Cdk2, Cyclin D, and Cdk6 genes. All RARβ/RXRα binding sites contained AGGTCA-like motifs. RA treatment also promoted liver regeneration after partial hepatectomy (PH). RA signaling was implicated in normal liver regeneration as the mRNA levels of RARβ, Aldh1a2, Crabp1, and Crbp1 were all induced 1.5 days after PH during the active phase of hepatocyte proliferation. RA treatment prior to PH resulted in early up-regulation of RARβ, Aldh1a2, Crabp1, and Crbp1, which was accompanied by an early induction of cell cycle genes. Western blotting for RARβ, c-myc, Cyclin D, E, and A further supported the early induction of retinoid signal and cell proliferation by RA treatment. Taken together, our data suggest that RA may regulate cell cycle progression and accelerates liver regeneration. Such effect is associated with an early induction of RA signaling, which includes increased expression of the receptor, binding proteins, and processing enzyme for retinoids.     

葛根总黄酮对载脂蛋白E基因缺陷小鼠动脉粥样硬化斑块形成的影响

目的探讨葛根总黄酮对载脂蛋白E基因缺陷小鼠主动脉窦动脉粥样硬化斑块形成的影响。方法将载脂蛋白E基因缺陷小鼠随机分为模型组、葛根总黄酮低剂量组、葛根总黄酮高剂量组及阿托伐他汀阳性药物组。常规生物化学法测定血清总胆固醇、甘油三酯及高密度脂蛋白胆固醇水平;采用主动脉根部连续石蜡切片、苏木素伊红染色观察组织形态学改变,测定载脂蛋白E基因缺陷小鼠主动脉窦动脉粥样硬化斑块大小、动脉粥样硬化斑块与管腔面积比。结果4组小鼠共检出斑块65个,4组虽都有典型的粥样斑块或/及纤维斑块等中晚期动脉粥样硬化病变形成,但组织学观察发现模型组部分斑块体积较大,汇合成片,管壁弥漫性增厚,管腔较狭窄,而葛根总黄酮治疗组及阿托伐他汀阳性药物组动脉粥样硬化斑块病变较局限,管腔狭窄程度较轻,并且葛根总黄酮高、低剂量组及阿托伐他汀阳性药物组斑块面积与管腔面积之比值显著低于模型组(分别为0.11%±0.04%、0.27%±0.04%和0.76%±0.33%,P<0.01),葛根总黄酮高剂量组斑块面积与管腔面积比值显著低于葛根总黄酮低剂量组(P<0.01)。结论葛根总黄酮一定程度抑制载脂蛋白E基因缺陷小鼠动脉粥样硬化斑块进展,该作用可能与降低小鼠血脂作用无明显关系。