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C57BL/KsJ-db/db-ApcMin/+ Mice Exhibit an Increased Incidence of Intestinal Neoplasms  [PDF]
Kazuya Hata,Masaya Kubota,Masahito Shimizu,Hisataka Moriwaki,Toshiya Kuno,Takuji Tanaka,Akira Hara,Yoshinobu Hirose
International Journal of Molecular Sciences , 2011, DOI: 10.3390/ijms12118133
Abstract: The numbers of obese people and diabetic patients are ever increasing. Obesity and diabetes are high-risk conditions for chronic diseases, including certain types of cancer, such as colorectal cancer (CRC). The aim of this study was to develop a novel animal model in order to clarify the pathobiology of CRC development in obese and diabetic patients. We developed an animal model of obesity and colorectal cancer by breeding the C57BL/KsJ- db /db (db/db) mouse, an animal model of obesity and type II diabetes, and the C57BL/6J- ApcMin/+ (Min/+) mouse, a model of familial adenomatous polyposis. At 15 weeks of age, the N9 backcross generation of C57BL/KsJ- db /db- ApcMin/+ (db/db-Min/+) mice developed an increased incidence and multiplicity of adenomas in the intestinal tract when compared to the db/m-Min/+ and m/m-Min/+ mice. Blood biochemical profile showed significant increases in insulin (8.3-fold to 11.7-fold), cholesterol (1.2-fold to 1.7-fold), and triglyceride (1.2-fold to 1.3-fold) in the db/db-Min/+ mice, when compared to those of the db/m-Min/+ and m/m-Min/+ mice. Increases (1.4-fold to 2.6-fold) in RNA levels of insulin-like growth factor (IGF)-1, IRF-1R, and IGF-2 were also observed in the db/db-Min/+ mice. These results suggested that the IGFs, as well as hyperlipidemia and hyperinsulinemia, promoted adenoma formation in the db/db-Min/+ mice. Our results thus suggested that the db/db-Min/+ mice should be invaluable for studies on the pathogenesis of CRC in obese and diabetes patients and the therapy and prevention of CRC in these patients.
Pitavastatin suppresses diethylnitrosamine-induced liver preneoplasms in male C57BL/KsJ-db/db obese mice
Masahito Shimizu, Yoichi Yasuda, Hiroyasu Sakai, Masaya Kubota, Daishi Terakura, Atsushi Baba, Tomohiko Ohno, Takahiro Kochi, Hisashi Tsurumi, Takuji Tanaka, Hisataka Moriwaki
BMC Cancer , 2011, DOI: 10.1186/1471-2407-11-281
Abstract: Male db/db mice were administered tap water containing 40 ppm DEN for 2 weeks and were subsequently fed a diet containing 1 ppm or 10 ppm pitavastatin for 14 weeks.At sacrifice, feeding with 10 ppm pitavastatin significantly inhibited the development of hepatic premalignant lesions, foci of cellular alteration, as compared to that in the untreated group by inducing apoptosis, but inhibiting cell proliferation. Pitavastatin improved liver steatosis and activated the AMPK-α protein in the liver. It also decreased free fatty acid and aminotransferases levels, while increasing adiponectin levels in the serum. The serum levels of tumor necrosis factor (TNF)-α and the expression of TNF-α and interleukin-6 mRNAs in the liver were decreased by pitavastatin treatment, suggesting attenuation of the chronic inflammation induced by excess fat deposition.Pitavastatin is effective in inhibiting the early phase of obesity-related liver tumorigenesis and, therefore, may be useful in the chemoprevention of liver cancer in obese individuals.Hepatocellular carcinoma (HCC) is a serious healthcare problem worldwide because of its increasing morbidity and high mortality. Chronic inflammation of the liver and subsequent cirrhosis, which are highly correlated with hepatitis B and hepatitis C viruses infection and alcoholic liver disease, are the strongest risk factors for HCC development. Recent evidence also indicates that obesity and related metabolic abnormalities, especially diabetes mellitus and insulin resistance, raise the risk of HCC [1-4]. In obese individuals, high levels of free fatty acid (FFA) flux into the liver from excess adipose tissue. This in turn promotes hepatic steatosis and inflammation through the production of pro-inflammatory cytokines, such as tumor necrosis factor (TNF)-α and interleukin (IL)-6, and is closely associated with liver carcinogenesis [5-7]. Aberrant lipogenesis in the liver, which is closely linked to obesity and metabolic syndrome, is also a domina
HPN, a Synthetic Analogue of Bromophenol from Red Alga Rhodomela confervoides: Synthesis and Anti-Diabetic Effects in C57BL/KsJ-db/db Mice  [PDF]
Dayong Shi,Shuju Guo,Bo Jiang,Chao Guo,Tao Wang,Luyong Zhang,Jingya Li
Marine Drugs , 2013, DOI: 10.3390/md11020350
Abstract: 3,4-Dibromo-5-(2-bromo-3,4-dihydroxy-6-(isopropoxymethyl)benzyl)benzene-1,2-diol (HPN) is a synthetic analogue of 3,4-dibromo-5-(2-bromo-3,4-dihydroxy-6-(ethoxymethyl)benzyl)benzene-1,2-diol (BPN), which is isolated from marine red alga Rhodomela confervoides with potent protein tyrosine phosphatase 1B (PTP1B) inhibition (IC 50 = 0.84 μmol/L). The in vitro assay showed that HPN exhibited enhanced inhibitory activity against PTP1B with IC 50 0.63 μmol/L and high selectivity against other PTPs (T cell protein tyrosine phosphatase (TCPTP), leucocyte antigen-related tyrosine phosphatase (LAR), Src homology 2-containing protein tyrosine phosphatase-1 (SHP-1) and SHP-2). The results of antihyperglycemic activity using db/ db mouse model demonstrated that HPN significantly decreased plasma glucose ( P < 0.01) after eight weeks treatment period. HPN lowered serum triglycerides and total cholesterol concentration in a dose-dependent manner. Besides, both of the high and medium dose groups of HPN remarkably decreased HbA1c levels ( P < 0.05). HPN in the high dose group markedly lowered the insulin level compared to the model group ( P < 0.05), whereas the effects were less potent than the positive drug rosiglitazone. Western blotting results showed that HPN decreased PTP1B levels in pancreatic tissue. Last but not least, the results of an intraperitoneal glucose tolerance test in Sprague–Dawley rats indicate that HPN have a similar antihyperglycemic activity as rosiglitazone. HPN therefore have potential for development as treatments for Type 2 diabetes.
澳洲滨藜的抗寒性研究  [PDF]
刘洁,李华,石元豹,曹兵
北方园艺 , 2013,
Abstract: 采用人工模拟降温处理方法,测定了澳洲滨藜枝、叶在不同低温处理下的电导率与主要渗透调节物质含量变化。结果表明随着温度的降低,澳洲滨藜枝、叶组织的相对电导率增大,原生质膜的透性增加,枝条萌芽率降低;组织中脯氨酸、可溶性糖含量增加,以通过渗透调节适应低温胁迫。电导法配合Logistic方程求得澳洲滨藜的半致死温度为-11.2℃,其抗寒性差于四翅滨藜。
藜对干旱胁迫的生理生化反应  [PDF]
孙存华?,李扬?,贺鸿雁?,孙东旭?,杜伟?,郑曦?
生态学报 , 2005,
Abstract: 干旱是植物最易遭受的胁迫之一,每年由于干旱胁迫给农业造成损失几乎相当于其他所有环境因子胁迫所造成的损失的总和。通过人工控制水分模拟干旱来研究生长期的藜对干旱胁迫的生理生化反应,以期望为干旱农业的高效生产提供理论依据。以盆栽的藜为材料,用控制浇水的方法分对照、轻度胁迫、中度胁迫、重度胁迫4个组,研究了不同程度干旱胁迫对藜叶片的水分状况、渗透调节物质、活性氧代谢以及内生保护系统的影响。结果表明:在干旱胁迫下,藜叶片相对含水量(rwc)、自由水含量(fwc)下降,束缚水含量(bwc)上升;可溶性糖、脯氨酸、k+、ca2+含量增加,表现出藜对适度干旱有一定的适应性。但重度干旱胁迫,o2.产生速率和丙二醛(mda)含量显著提高,导致膜损伤,质膜透性上升;超氧化物歧化酶(sod)、过氧化物酶(pod)活性先上升,后下降;抗坏血酸(asa)含量降低。过分干旱胁迫对藜会造成一定伤害。
NaCl胁迫对藜麦幼苗生长和抗氧化酶活性的影响  [PDF]
刘文瑜,杨发荣,,,魏玉明,,
- , 2017,
Abstract: 以国内首个藜麦自育品种“陇藜1号”为材料,采用温室盆栽法,以蒸馏水处理作为共同对照(CK),分别用100、200、300、400和500 mmol/L NaCl水溶液处理藜麦种子和盆栽幼苗,通过测定种子萌发指标及处理后第5、10、15天藜麦幼苗叶片叶绿素、可溶性糖、脯氨酸、MDA含量及抗氧化酶活性,分析NaCl胁迫对藜麦生长发育及其生理特性的影响,探讨藜麦的耐盐生理机制。结果表明:(1)随NaCl浓度的升高,藜麦种子发芽率、发芽势、发芽指数和活力指数先升高后下降,且在200 mmol/L NaCl处理下种子各发芽指标均达到最高,比CK分别升高了6.40%、28.18%、20.77%和30.91%。(2)随NaCl浓度的升高,藜麦幼苗根部和茎部生长均受到抑制,且茎部生长受到抑制程度大于根部。(3)随NaCl浓度的升高和处理时间的延长,藜麦幼苗叶片叶绿素含量先升高后下降,可溶性糖、脯氨酸和MDA含量逐渐升高,SOD、POD、CAT和APX活性增强。研究发现,低浓度盐胁迫处理可增加藜麦幼苗叶片内渗透调节物质含量,增强抗氧化酶活性,清除多余活性氧,从而促进幼苗根系生长,提高幼苗耐旱性;初步推断藜麦耐盐阈值为200~300 mmol/L NaCl。
Influences of obese (ob/ob) and diabetes (db/db) genotype mutations on lumber vertebral radiological and morphometric indices: Skeletal deformation associated with dysregulated systemic glucometabolism
Katherine M Burkemper, David R Garris
BMC Musculoskeletal Disorders , 2006, DOI: 10.1186/1471-2474-7-10
Abstract: The influences of single-gene missense mutations, expressing either diabetes (db/db) or obese (ob/ob) metabolic syndromes on vertebral maturation and development in C57BL/KsJ mice were evaluated by radiological and macro-morphometric analysis of the resulting variances in osteodevelopment indices relative to control parameters between 8 and 16 weeks of age (syndrome onset @ 4 weeks), and the influences of low-dose 17-B-estradiol therapy on vertebral growth expression evaluated.Associated with the indicative genotypic obesity and hyper-glycemic/-insulinemic states, both db/db and ob/ob mutants demonstrated a significant (P ≤ 0.05) elongation of total lumbar vertebrae column (VC) regional length, and individual lumbar vertebrae (LV1-5) lengths, relative to control VC and LV parameters. In contrast, LV1-5 width indices were suppressed in db/db and ob/ob mutants relative to control LV growth rates. Between 8 and 16 weeks of age, the suppressed LV1-5 width indices were sustained in both genotype mutant groups relative to control osteomaturation rates. The severity of LV1-5 width osteosuppression correlated with the severe systemic hyperglycemic and hypertriglyceridemic conditions sustained in ob/ob and db/db mutants. Low-dose 17-B-estradiol therapy (E2-HRx: 1.0 ug/ 0.1 ml oil s.c/3.5 days), initiated at 4 weeks of age (i.e., initial onset phase of db/db and ob/ob expressions) re-established control LV 1–5 width indices without influencing VC or LV lengths in db/db groups.These data demonstrate that the abnormal systemic endometabolic states associated with the expression of db/db and ob/ob genomutation syndromes suppress LV 1–5 width osteomaturation rates, but enhanced development related VC and LV length expression, relative to control indices in a progressive manner similar to recognized human metabolic syndrome conditions. Therapeutic E2 modulation of the hyperglycemic component of diabetes-obesity syndrome protected the regional LV from the mutation-induced osteopeni
红参芦头的应用研究  [PDF]
刘镜如,宋士成,刘学法,刘定宇
中国中药杂志 , 1988,
Abstract: 传统记载,人参芦头具有涌吐作用。实验表明,红参芦头和红参具有相同的成份,临床观察未发现有致呕作用.红参可带芦入药.
人参去芦问题的文献研究  [PDF]
袁惠南,李老占,吴建平,徐红
中国中药杂志 , 1987,
Abstract: 本文通过文献研究,探讨了参芦“吐人”学说的由来,分析了历代医药学家的论述,阐述了用参去芦的形成及沿革的历史与现状,并扼要介绍了近年来对参芦的化学,药理与临床研究结果,旨为深一步研究和正确评价参芦提供药学史料及新近的研究资料。
棉花芦管育苗新技术研究Ⅵ.棉花芦管育苗移栽技术  [PDF]
宋家祥 , 陆建飞 , 顾世梁
扬州大学学报(农业与生命科学版) , 2001,
Abstract: ????9年芦管育苗移栽试验及其栽培实践结果表明:用芦管培育适龄早发棉苗,应抓住芦管预腐处理、高肥力完全型营养土制备、病虫草防除、种子精选、适期播种和及时分植壮育与移栽等关键技术
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