山楂原花青素和VC联合通过Wnt/β-catenin通路减轻胰岛素抵抗大鼠肝脏氧化应激

目的：探讨山楂原花青素（hawthorn proanthocyanidin，HPC）和VC联合通过Wnt/β-catenin通路减轻胰岛素抵抗大鼠氧化应激的机制。方法：80 只雄性Wistar大鼠通过高脂膳食法建立胰岛素抵抗模型，10 只饲喂普通饲料作为对照组，检测大鼠造模前后体质量变化和造模后空腹血糖、血清胰岛素浓度，比色法检测血清丙氨酸氨基转移酶（alanine aminotransferase，ALT）、天冬氨酸氨基转移酶（aspartate aminotransferase，AST）和碱性磷酸酶（alkaline phosphatase，ALP）活力；随机选取50 只造模成功的胰岛素抵抗大鼠分为模型组、HPC组（56 μg/mL）、VC组（180 μg/mL）、HPC（56 μg/mL）＋VC（180 μg/mL）组和二甲双胍（2 μg/mL）组，每组各10 只。连续给药12 周，测定各组大鼠血液中葡萄糖、胰岛素浓度以及肝匀浆中超氧化物歧化酶（superoxide dismutase，SOD）、过氧化氢酶（catalase，CAT）、谷胱甘肽过氧化物酶（glutathione peroxidase，GPx）、还原型谷胱甘肽（glutathione，GSH）、丙二醛（malondialdehyde，MDA）的水平；实时定量聚合酶链式反应检测Wnt1、轴蛋白（Axin）、糖原合酶激酶-3β（glycogen synthasc kinase-3β，GSK-3β）、腺瘤样息肉病蛋白（adenomatous polyposis coli protein，APC）、β-catenin、过氧化物酶体增殖物激活受体γ（peroxisome proliferators-activated receptors γ，PPARγ）的mRNA表达水平；蛋白质印迹法检测肝组织Wnt1、β-catenin和PPARγ的蛋白表达水平；荧光共振能量转移分析法检测Wnt1和Dsh蛋白结合的情况。结果：80 只大鼠给予高脂膳食喂养，有54 只造模成功，成功率67.5%。造模后，模型组大鼠的体质量以及空腹血糖、血清胰岛素、ALT、AST和ALP水平均极显著高于对照组大鼠（P＜0.01）。与模型组相比，HPC组、HPC＋VC组和二甲双胍组大鼠肝匀浆中各指标水平均有极显著差异（P＜0.01），HPC＋VC组对肝匀浆中各指标干预效果显著优于HPC组（P＜0.05）；HPC＋VC组Wnt1和β-catenin的mRNA相对表达水平极显著降低（P＜0.01），Axin、GSK-3β、APC和PPARγ的mRNA相对表达水平极显著升高（P＜0.01）；HPC＋VC组Wnt1和β-catenin的蛋白相对表达水平极显著降低（P＜0.01），PPARγ的蛋白表达水平极显著升高（P＜0.01）；HPC＋VC组的荧光共振能量转移信号明显减弱，说明随着时间的延长，Wnt1与Dsh之间的结合力明显减弱，形成的异源二聚体数量明显减少。结论：HPC和VC联合可通过Wnt/β-catenin通路改善胰岛素抵抗大鼠肝脏氧化应激状况。     

Eubacterial 16S-rDNA amplicon profiling: a rapid technique for comparison and differentiation of heterotrophic plate count communities from drinking water

Determination of the heterotrophic plate count (HPC) is commonly used as a surrogate to assess the general microbial water quality in drinking water. For routine monitoring applications, the HPC is investigated in a quantitative way. However, qualitative data about the HPC bacterial community composition and/or population dynamics are required for particular situations. In order to provide fast and efficient qualitative approaches, molecular biological DNA profiling techniques seem to be suitable tools for the analysis of the total HPC community composition. In this work a DNA profiling technique is presented, which was recently demonstrated by our group to have potential for the rapid qualitative comparison and differentiation of HPC communities from raw and drinking water. The presented approach consists of a polymerase chain reaction (PCR)-based denaturing gradient gel electrophoresis (DGGE) for the generation of 16S-rDNA amplicon fingerprints from whole HPC community DNA extracts. In the context of this proceeding, the methodical background is presented and possible scientific merits as well as potential water management applications are discussed. Selected examples of (i) the demonstration of selective growth of HPC populations on different media and the comparison to the total in situ drinking water eubacterial community, (ii) the screening for HPC community variations at different locations of a drinking water distribution system, and (iii) the influence assessment on groundwater HPC communities by an infiltrating treated sewage effluent (bacterial source tracking) are given.     

Heterotrophic plate count bacteria--what is their significance in drinking water?

While the literature documents the universal occurrence of heterotrophic plate count (HPC) bacteria in soils, foods, air, and all sources of water, there is a lingering question as to whether this group of organisms may signal an increased health risk when elevated populations are present in drinking water. This paper reviews the relevant literature on HPC bacteria in drinking water, the lack of clinical evidence that elevated populations or specific genera within the HPC flora pose an increased health risk to any segment of the population, and the appropriate uses of HPC data as a tool to monitor drinking water quality changes following treatment. It finds no evidence to support health-based regulations of HPC concentrations.     

Virulence and risk from drinking water of heterotrophic plate count bacteria in human population groups

Bacteria are natural inhabitants of all aqueous environments. The heterotrophic plate count is a means of assessing the concentration of these bacteria in foods, water, and water filtration systems. Methods vary, but are designed to enumerate bacteria that have evolved an environmental lifestyle. Most commonly, low nutrient, low ionic strength culture media are employed. The group of environmental bacteria enumerated depends on the media formulation and incubation conditions but are commonly known as heterotrophic plate count (HPC) bacteria; in Europe, this group is also referred to as autochthonous flora. While HPC inhabit an environmental niche, there has been concern that at some concentration they may be a human health risk. A review of the literature, including animal and human feeding studies, analysis of virulence factors, and outbreaks demonstrates that HPC bacteria as enumerated on HPC culture media have not been established as a human health threat at any concentration in drinking water or foods.     

Consumer perception of natural hot-pepper cheeses

Hot-pepper cheese (HPC) is a growing category of flavored natural cheese. The objective of this study was to evaluate consumer perception of HPC using a combination of quantitative survey methods and consumer evaluation of HPC. An online survey (n = 510) was conducted to understand drivers of purchase for the HPC category. Consumers of HPC answered maximum difference exercises and an adaptive choice-based conjoint activity focused on HPC attributes. Subsequently, natural HPC were manufactured in duplicate with 5 different hot-pepper blends with a range of heat intensities and distinct color differences. Trained panel profiling and consumer-acceptance testing (n = 194 consumers) were conducted on the cheeses. Three clusters of consumers were identified from the online survey. Cluster 1 (n = 175) were traditional HPC consumers, and cluster 2 (n = 152) preferred milder HPC. Cluster 3 (n = 183) showed preference for spicier HPC as well as novel HPC, such as those made with habanero peppers or white Cheddar cheese. Conceptually, the overall ideal HPC was a Monterey Jack with medium-sized, multicolored pieces of jalapeno peppers and a medium heat and spiciness. Heat and spiciness intensity and type of cheese were the most important attributes. The 5 HPC used in consumer testing had a distinct range (low to high) of hot-pepper burn and heat intensity by trained panel profiling. Consumer overall liking increased as hot-pepper burn and heat intensity increased to a certain point, indicating HPC consumers may have an optimal point for heat and spiciness in HPC. Consumers also preferred HPC with multicolored pepper pieces over those with a single pepper color, consistent with survey results. Consumers who self-reported that they prefer mild- or medium-spicy foods (mild consumers) preferred HPC that were less intense in hot-pepper burn than consumers who self-reported preference for hot or spicy foods (hot consumers). Most HPC consumers preferred HPC with higher heat intensity and were also motivated by visual characteristics of HPC.     

山楂原花青素下调Traf6/NF-κB信号通路诱导肝癌细胞凋亡

目的：探讨山楂原花青素（hawthorn procyanidins,HPC）诱导肝癌细胞Huh-7增殖和促进其凋亡的机制。方法：体外常规培养Huh-7细胞株和过表达Traf6基因Huh-7细胞株,配制0、5、10、20、40、80μg/mL不同质量浓度的HPC,采用细胞计数8(cell counting kit-8,CCK-8)试剂盒检测HPC对Huh-7细胞和过表达Traf6基因Huh-7细胞增殖的抑制作用,并选40μg/mL作为HPC实验质量浓度;利用实时定量聚合酶链反应检测Huh-7细胞中Traf6、NF-κB?p65、Bax和Caspase-3的mRNA表达水平;利用蛋白质免疫印迹法（Western blot）检测Huh-7细胞中Traf6、NF-κB p65、Bax和Caspase-3蛋白表达水平;利用Annexin V-FITC/PI凋亡检测试剂盒检测HPC对Huh-7细胞凋亡的影响。结果：HPC质量浓度大于20μg/mL时可以明显抑制Huh-7细胞增殖,并随HPC质量浓度升高Huh-7细胞的相对存活率显著降低（P<0.05）;Traf6蛋白过表达可以促进Huh-7细...     

Surface rheological properties of hydroxypropyl cellulose at air–water interface

Hydroxypropyl cellulose (HPC) is a neutral polysaccharide derived from cellulose. It is, notably, added to non-dairy whipped topping. However, if the function of HPC is well recognized, its behavior is not well known. The interaction of HPC with each component (dispersed fat droplets, emulsifiers, proteins) should be studied step by step. In order to understand better the function of HPC, air–water interfacial rheology was used to characterize the behavior of HPC at this interface, with and without emulsifier. As HPC is a flexible polymer, it shows, at room temperature, a medium value of intrinsic viscosity, which is of the same order as of galactomannan ones. Addition of HPC in the aqueous phase leads to a decrease of the air–water surface tension (down to about 45–41 mN/m) where xanthan and guar gum have smaller or negligible effect. The time to reach the equilibrium of surface tension is reached after several hours. The smaller the concentration, the longer it is to reach the equilibrium. The competition between HPC and palmitic ester (E473) was studied. Kinetics of surface tension evolution of E473/HPC systems are different from that of HPC alone: mixed systems and HPC show an evolution of surface tension in three steps that could be explained through E473/HPC competition for the air/continuous phase interface.     

可食性SPI/HPC膜的性能

研究了不同浓度的羟丙基纤维素(HPC)对大豆分离蛋白(SPI)膜性能的影响.结果表明,HPC的添加浓度对SPI膜的性能有显著影响.在SPI膜中添加HPC后,膜的抗拉强度明显增加,透光率降低,表面疏水性增大.这表明HPC和SPI分子之间发生了强的相互作用,进一步影响膜的性能.     

Benefits of Water Safety Plans: microbiology, compliance, and public health

The Water Safety Plan (WSP) methodology, which aims to enhance safety of drinking water supplies, has been recommended by the World Health Organization since 2004. WSPs are now used worldwide and are legally required in several countries. However, there is limited systematic evidence available demonstrating the effectiveness of WSPs on water quality and health. Iceland was one of the first countries to legislate the use of WSPs, enabling the analysis of more than a decade of data on impact of WSP. The objective was to determine the impact of WSP implementation on regulatory compliance, microbiological water quality, and incidence of clinical cases of diarrhea. Surveillance data on water quality and diarrhea were collected and analyzed. The results show that HPC (heterotrophic plate counts), representing microbiological growth in the water supply system, decreased statistically significant with fewer incidents of HPC exceeding 10 cfu per mL in samples following WSP implementation and noncompliance was also significantly reduced (p < 0.001 in both cases). A significant decrease in incidence of diarrhea was detected where a WSP was implemented, and, furthermore, the results indicate that population where WSP has been implemented is 14% less likely to develop clinical cases of diarrhea.     

Epidemiology of human listeriosis and seafoods

While rarely diagnosed prior to 1960, more than 10,000 cases of listeriosis were recorded in the medical literature between 1960 and 1982, and thousands more have been reported annually world-wide [Rocourt J., 1991. Human listeriosis, 1989. WHO/HPP/FOS/91.3, World Health Organization, Geneva, Switzerland; Rocourt, J., Brosch, R., 1992. Human listeriosis, 1990. WHO/HPP/FOS/92.3, World Health Organization, Geneva, Switzerland; Rocourt, J., Jacquet, Ch., Bille, J., 1997. Human listeriosis, 1991/1992. WHO/FNU/FOS/97.1, World Health Organization, Geneva, Switzerland]. This widespread increase in reporting is most likely due to demographic trends and changes in food production, processing and storage, especially the extended cold food chain and the ability of Listeria monocytogenes to grow at low temperatures: L. monocytogenes is a bacterium responsible for opportunistic infections, preferentially affecting individuals whose immune system is perturbed, including pregnant women, newborns, people over 65 years, immunocompromised patients, such as cancer victims, transplant recipients, people on hemodialysis and AIDS patients. Thus, the increasing lifespan and medical progress allowing immunodeficient individuals to survive, partially explains the increasing incidence of listeriosis. Moreover, L. monocytogenes is ubiquitous and can grow at temperatures as low as 0 degrees C. At this temperature growth is very slow. The expansion of the agro-food industry, the widespread use of systems of cold storage and changes in consumers demands have led to a large increase in the pool of Listeria that can cause foodborne infections.     

不同蛋白质含量大豆结瘤特性与根瘤氮代谢物含量的比较分析

为了明确高蛋白野生大豆氮素积累规律,本试验选取3类不同蛋白质含量的大豆材料,在各生育期对根瘤生长特性及根瘤氮代谢物的含量变化进行研究,结果表明：籽粒蛋白质含量与R2～R8时期的根瘤数呈显著正相关。V6～R2期高蛋白野生大豆根瘤数增加较快,整个生育期根瘤重不断增加。三种类型大豆的血红蛋白含量、单株血红蛋白总量在R2～R8期与籽粒蛋白质含量呈显著正相关。在V6到R8期高蛋白野生大豆血红蛋白含量、总量都明显高于其它两种类型大豆材料,差异性均达到显著水平。R2～R8期三种类型大豆游离氨基酸含量、酰脲含量均呈下降趋势,高蛋白野生大豆游离氨基酸含量低于、而酰脲含量却又高于其它两种类型材料,且差异性显著。说明高蛋白野生大豆根瘤衰老较慢、根瘤内氮代谢物含量丰富,生育后期仍具有较强的酰脲合成与运输能力是形成该类型大豆籽粒高蛋白质含量的原因之一。     

Temporal variation of microbiological and chemical quality of noncarbonated bottled drinking water sold in Sri Lanka

Use of bottled water in Sri Lanka has increased over the last decade, while new brands of bottled water are often introduced to the market. However, the manufacturers' adherence to bottled water regulations is questionable, raising concerns regarding the quality of bottled water. The objective of the current study was to investigate the microbiological and chemical quality of bottled water in Sri Lanka. Thirty bottled water brands were sampled and their chemical and microbiological parameters were analyzed. Microbiological analysis was carried out within 1 to 3, 3 to 6, 6 to 9, and 9 to 12 mo after the date of manufacture. The results indicated that 63% of brands tested exceeded the levels permitted by the Sri Lanka Standards Institution (SLSI) for presumptive total coliforms (TC) (<10 cfu per 100 mL) whereas 97% brands exceeded the World Health Organization (WHO) permitted level. Thirty percent of brands exceeded the limit for presumptive fecal coliforms (FC) (0 cfu per 100 mL in accordance with WHO permitted levels, SLSI and the Sri Lanka Health Ministry requirement). Eighty percent of brands showed higher heterotrophic plate counts (HPC) which exceeded the WHO guidelines for bottled drinking water. Throughout their shelf life, the counts of TC, FC, and HPC bacteria decreased. Bacteria identified were Klebsiella pneumoniae ssp. pneumoniae, Enterobacter cloacae, Pseudomonas aeruginosa, and Pasteurella haemolytica, the most frequently being P. aeruginosa. The dominant fungi identified were Aspergillus sp. and Penicillium sp. Inorganic chemical parameters were within permitted levels for all brands except for initial content of ammonia. The results of this study show the need for the bottling industry to be monitored closely by relevant authorities, in order to provide safe bottled drinking water to consumers in Sri Lanka.     

Evaluating Bioactive Food Components in Obesity and Cancer Prevention

Research into bioactive food compounds (BFC) continues to evolve albeit with shared challenges among scientists in the fields of obesity and cancer treatment and prevention. Given the diversity of scientific disciplines involved in evaluating BFC, multidisciplinary conferences provide opportunities to update the state of the science and critically discuss conceptual and methodological challenges encountered in studying BFC in both preclinical and clinical trials. This overview is an introduction to presentations given at a conference sponsored by the National Cancer Institute of the National Institutes of Health and the University of Alabama at Birmingham, which convened a multidisciplinary group of researchers evaluating BFC in obesity and cancer prevention. Full presentations can be viewed in video format at http://www.norc.uab.edu/courses/conferences/conference2013.     

The characteristics of a microcapsule with an entirely new wall material, ''silicone–resin–polypeptide'', and its application

We developed a non-water gel product comprising HPC and PEG, reacting hydration with water. We investigated the gelation mechanism of HPC/PEG gel by means of a stress-controlled rheometer and an X-ray diffractometer. According to the results, the mechanism has two factors: entanglement of the HPC polymer chain and cross-linkage of the microcrystal domain of the HPC main chain. The HPC/PEG gel is useful as the basic material of the cosmetic plaster that causes skin surface temperature to rise and the blood stream to accelerate.     

壳聚糖/羟丙基纤维素共混材料的流变学与润湿性

探讨壳聚糖/羟丙基纤维素（HPC）共混材料的流变性与润湿力。使用RVDV-ⅡPRO黏度计测定体系的黏度和剪切应力以考察组成与温度对材料流变性的影响;借助K100表面张力仪测定膜的接触角以考察材料的润湿力。结果显示：除壳聚糖与HPC质量分数均≤1%的共混溶液近似为牛顿流体外,其余均为非牛顿流体;溶液黏度随温度升高而降低;20℃时共混膜的润湿力为甲醇＞DMF＞乙二醇＞水;膜最低水接触角依次为20℃＜40℃＜30℃;弱酸或弱碱性介质均可提高膜的亲水性;当HPC质量分数为0～1%时,水接触角由空白值71.04°最低可降至55.38°。该结果对壳聚糖/HPC共混材料的纺丝与应用有指导作用。     

Permeability and Mechanical Properties of Cellulose-Based Edible Films

Factors affecting barrier properties [oxygen permeability (OP) and water vapor permeability (WVP)] and mechanical properties [tensile strength (TS) and elongation (E)] were investigated for methyl cellulose (MC) and hydroxypropyl cellulose (HPC) films. OP, WVP and TS of MC and HPC films increased as the molecular weight (MW) of the cellulose increased. E of MC films increased as MW increased, but E of HPC films was highest for the intermediate MW of 370,000. OP, WVP and TS of MC films were not a function of thickness, but E slowly increased as film thickness increased. OP and WVP of HPC films were not relatable to film thickness, but TS and E of HPC films slowly increased as film thickness increased. TS decreased and E increased for both film types as concentration of plasticizers was increased. Plasticizers enhanced or retarded OP and WVP of cellulose-based films, depending on their concentrations.     

Growth of Mycobacterium avium subsp. paratuberculosis in the presence of hexadecylpyridinium chloride, natamycin, and vancomycin

A design-of-experiments approach was used to examine the effect of hexadecylpyridinium chloride (HPC), alone or in combination with the antibiotics vancomycin and natamycin, on the growth of Mycobacterium avium subsp. paratuberculosis (MAP). At concentrations above 74.4 microg/ml, HPC had a highly significant detrimental effect on the growth of MAP, whereas natamycin at 10.8 and 21.6 microg/ml and vancomycin at 5.2 and 10.4 microg/ml did not have such an effect. Titration of the amount of HPC tolerated by MAP indicated that growth can occur in the presence of 24.8 microg/ml or lower. Processing of bovine fecal specimens indicated that reducing the concentration of HPC from 32.22 to 1.07 mg/ml during decontamination may improve detection when cultures are grown on solid medium but not when cultures are grown in liquid medium. Further investigation into optimizing HPC concentration during processing of fecal samples is warranted. Natamycin, in conjunction with vancomycin, may be useful for controlling fungal contamination during isolation of MAP from fecal samples.     

Structure Elucidation of Hydroxypropyl Cellulose Homogenously Prepared from NaOH/Urea Aqueous Solution

Hydroxypropyl celluloses (HPC) were homogenously synthesized by the reaction of cellulose with propylene oxide in NaOH/urea aqueous solution.Water-soluble HPC with molar degree of substitution (MSNMR) in the range of 0.52～ 0.78 was prepared from microcrystalline cellulose,cotton linters,and spruce sulfite pulp.The structure of the HPC samples was characterized by means of FT-IR,NMR,gas chromatography (GC),and size exclusion chromatography (SEC) analyses.Three types of cellulose samples with different molecular weights were found to dissolve well in the NaOH/urea solvent with no obvious differences in reactivity and regioselectivity.The relative reactivity of hydroxyl groups in the glycosyl unit was in the following order:O-6 ＞ O-2 ＞O-3.In addition,the results of the study indicated that the tandem reaction during hydroxypropylation could be ignored.     

Understanding the distribution system as a bioreactor: a framework for managing heterotrophic plate count levels

It is important to manage the level of heterotrophic plate count (HPC) bacteria in drinking water. Since the vast majority of HPCs measured in the distribution system are normally actually produced there, managing HPC numbers implies managing the distribution system as a bioreactor. This paper proposes a new concept, the HPC Production Index (HPI), which is the ratio of HPC production in a given distribution system to that produced by an essentially biostable water entering that same system. HPI is related to various physical, chemical and water quality factors such as contact time, disinfectant residual and level of biodegradable organic matter, which affect the performance of the distribution system as a bioreactor. HPI therefore provides a conceptual framework for managing distribution system HPC levels.