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1.
Definite lesions in the exocrine pancreas were produced when SMA mice were immunized eight times at intervals of 30 days with a mixture of extract of pooled pancreas from syngeneic mice and the capsular polysaccharide of Klebsiella pneumoniae type 1 Kasuya strain (CPS-K), whereas no pancreatic lesions were produced in mice given CPS-K alone or pancreatic extract alone. The typical histological changes were characterized by infiltration with lymphocytes, plasma cells, and other mononuclear cells, degeneration and lysis of the acinar cells, destruction of the lobular architecture, and replacement by fatty tissue and fibrous connective tissue. The endocrine islets were well preserved. No specific histological changes were produced in the organs other than the pancreas in these mice. Most of mice immunized with pancreatic extract mixed with CPS-K produced serum precipitins to syngeneic pancreatic antigens. However, severe pancreatic lesions were also produced in mice showing no definite precipitin production.  相似文献   

2.
The ethanolic extract of seeds of S. cumini increased body weight and decreased blood sugar level in alloxan diabetic albino rats. Level of significance for decrease in blood sugar after feeding alcoholic extract of S. cumini seeds in various doses was highly significant. The extract feeding showed definite improvement in the histopathology of islets. The most important finding is that the blood sugar level, which once dropped to normal levels after extract feeding was not elevated when extract feeding was discontinued for 15 days.  相似文献   

3.
The stance of pterosaurs on land is traditionally a controversial question. Here, we show that pterosaurs like Anhanguera piscator were quadrupeds. An osteological model of A. piscator was three-dimensionally built in digital space. The reconstructed muscles of its pelvic girdle were then placed on their points of origin and insertion to allow the biomechanical calculations to find the most efficient stance on land to be performed. The hindlimb readjustment (i.e. the repositioning of the hindlimb according to the achieved results) led to a pelvic counterclockwise displacement at 10°, which means that the ilium previously placed at 0° regarding an axis parallel to the ground was moved (and so the whole pelvis) 10° up from the preacetabular process. This new position prevents A. piscator from having a fully upright stance. A 10° displacement of the pelvic girdle would compel the forelimbs to be highly sprawled. Therefore, this study affords A. piscator having a quadrupedal gait and demonstrates that a bipedal stance is not viable once the lever arm values decrease abruptly both for extensor and flexor muscles during the femoral extension. This is the first time this approach is used to shed light on this question.  相似文献   

4.
The current study was aimed to investigate pancreatic protective and anti-diabetic activities of the aqueous extract of Derris reticulata stem. First, we evaluated a cytoprotective potential of D. reticulata extract on alloxan-induced damage in vitro. Treatment with D. reticulata extract at the doses of 250 and 500 μg/ml significantly increased cell viability of the pancreatic β-cell line RINm5F after exposure of alloxan. The anti-hyperglycemic activity of D. reticulata extract was further studied in alloxan-induced diabetic rats. A significant reduction in blood glucose level along with an increase in body weight was observed in diabetic rats treated with D. reticulata extract at 250 mg/kg body weight for 15 days. Serum aspartate transaminase and alanine transaminase levels were also significantly decreased compared to diabetic control rats. In accordance with in vitro cytoprotective effect, histopathological examination revealed that pancreatic islet cells of the extract-treated diabetic rat were less damage than those of the untreated diabetic group. In order to find another possible mechanism of action underling hypoglycemic activity, the effect on glucose absorption was examined using everted sac jejunum. The results showed that D. reticulata extract suppressed glucose absorption from small intestine. To corroborate safety use of D. reticulata extract, acute oral toxicity was also conducted in rats. Our results showed that none of the tested doses (250, 500, 1,000, and 2,000 mg/kg) induced signs of toxicity or mortality after administration of the extract. The results suggested that D. reticulata extract possess anti-diabetic activity, which resulting from its pancreatic cytoprotective effect and inhibition of intestinal glucose absorption.  相似文献   

5.
Methanolic extract of P. amarus was found to have potential anti-oxidant activity as it could inhibit lipid peroxidation, and scavenge hydroxyl and superoxide radicals in vitro. The amount required for 50% inhibition of lipid peroxide formation was 104 microg/ml and the concentrations needed to scavenge hydroxyl and superoxide radicals were 117 and 19 microg/ml respectively. The extract was found to reduce the blood sugar in alloxan diabetic rats at 4th hr by 6% at a dose level of 200 mg/kg body wt and 18.7% at a concentration of 1000 mg/kg body wt. Continued administration of the extract for 15 days produced significant (P < 0.001) reduction in blood sugar. On 18th day after alloxan administration values were almost similar to normal in the group taking 1000 mg/kg body wt.  相似文献   

6.
The composition, half life and hyperglycemic action of the porcine gastrointestinal glucagon-like immunoreactive materials were examined. Glucagon immunoreactivity (GI) measured using specific antiglucagon serum was more abundunt in the extract from the gastric fundus than in the one from the small intestine. When the extract from the gastric fundus was injected in dogs, the half life (T1/2) of total glucagon-like immunoreactivity (total GLI) measured using nonspecific antiglucagon serum was 9.5 +/- 1.1 min (mean +/- SEM), which was longer than that of crystalline pancreatic glucagon, 3.4 +/- 0.2 min, but shorter than that of the extract from the small intestine, 15.9 +/- 1.3 min. On the other hand, T1/2 for GI from the gastric fundus was 5.1 +/- 0.9 min, which was not significantly different from that of crystalline pancreatic glucagon. Blood sugar levels were significantly increased from the basal by 25 +/- 4 mg/100 ml at 10 min and 19 +/- 4 mg/100 ml at 15 min following an injection of the extract from the gastric fundus, but such a change in blood sugar levels was not demonstrated when the extract from the small intestine was injected. These results suggest that GI of the gastric fundus is close to pancreatic glucagon in respect of its metabolism and hyperglycemic activity.  相似文献   

7.
Glis3 is a member of the Gli-similar subfamily. GLIS3 mutations in humans lead to neonatal diabetes, hypothyroidism, and cystic kidney disease. We generated Glis3-deficient mice by gene-targeting. The Glis3−/− mice had significant increases in the basal blood sugar level during the first few days after birth. The high levels of blood sugar are attributed to a decrease in the Insulin mRNA level in the pancreas that is caused by impaired islet development and the subsequent impairment of Insulin-producing cell formation. The pancreatic phenotypes indicate that the Glis3-deficient mice are a model for GLIS3 mutation and diabetes mellitus in humans.  相似文献   

8.
目的研究滴水珠与半夏生药及其提取物抗五步蛇毒的作用。方法将ICR小鼠随机分为半夏生药组、半夏醇提物组、滴水珠生药组、滴水珠醇提物组、空白对照组、阳性对照组及模型组,各组小鼠均灌胃给药7天,并观察各给药组小鼠的体重变化情况;在末次给药1h后于小鼠腹腔注射五步蛇毒,观察各组小鼠的中毒表现,并统计各组小鼠的死亡率,比较各组小鼠的肝脏指数、脾脏指数及胸腺指数,并对各组小鼠血浆纤维蛋白原(FIB)、血浆凝血酶原时间(PT)、凝血酶时间(TT)、活化部分凝血酶时间(APTT)以及血小板(PLT)、红细胞(RBC)和白细胞(WBC)计数进行比较。结果半夏和滴水珠醇提物、半夏和滴水珠生药均可降低五步蛇毒中毒小鼠的死亡率,对五步蛇毒引起的小鼠PT、TT、APTT上升和FIB下降具有显著的抑制作用,与模型组相比P〈0.05;并可影响五步蛇毒中毒小鼠外周血血小板(PLT)、红细胞(RBC)和白细胞(WBC)计数,与模型组相比P〈0.05。但滴水珠和半夏生药可引起小鼠体重下降,并影响肝脏、胸腺和脾脏指数,与空白对照组相比P〈0.05。结论半夏和滴水珠醇提物及半夏和滴水珠生药均具有一定的抗五步蛇毒作用,乙醇提取能降低半夏和滴水珠的毒性。  相似文献   

9.
Most haematophagous insect vectors can also use sugar as an energy source; thus their sugar‐feeding behaviour influences their longevity and blood‐feeding rate and hence their vectorial capacity. Scant information is available on the sugar‐feeding behaviour of Culicoides Latreille biting midges (Diptera: Ceratopogonidae), which are vectors of bluetongue and Schmallenberg viruses. The longevity of laboratory‐reared Culicoides nubeculosus (Meigen) under fluctuating temperatures (16 and 28 °C) and with access to water or water and blood was on average 6.4 days and 8.9 days, respectively, which was around one third of the lifespan of siblings with access to sugar or sugar and blood (22.2 days and 27.1 days, respectively). Access to honeydew significantly increased the midge's longevity, whereas the provision of extrafloral nectaries had no impact. Females with access to sugar produced a significantly higher number of eggs (65.5 ± 5.2) than their starved sisters (45.4 ± 8.4). More than 80% of field‐caught female Culicoides from the two most abundant European groups, Obsoletus (n = 2243) and Pulicaris (n = 805), were fructose‐positive. Fructose‐positivity was high in all physiological stages and no seasonal variability was noted. The high rate of natural sugar feeding of Culicoides offers opportunities for the development of novel control strategies using toxic sugar baits and for the monitoring of vector‐borne diseases using sugar‐treated FTA (nucleic acid preservation) cards in the field.  相似文献   

10.
We examined the effects of various partitions of Salvadora persica extract on lipid profile (LP), lipid peroxidation, and insulin sensitivity (IS) of diabetic rats. The rats were divided into normal control, diabetic control (DC), standard, sham, and test groups. The test groups were treated with an oral dose of 200, 400, and 600 mg/kg of crude, aqueous, and ethyl acetate partition of S. persica extract. After 21 days of experiment, the fasting blood glucose (FBS), LPs, lipid peroxidation, IS, liver enzymes levels, liver histopathology, and body weight alteration were evaluated. A significant decrease in FBS and lipid profile (except HDL) were observed in rats treated with various dose of extract compared with the DC rats ( P < 0.05). Treating diabetic rats with various extracts of S. persica meaningfully decreased the level of malondialdehyde ( P < 0.05). Animals treated with various dose of aqueous extract showed better results ( P < 0.01). On the basis of used indirect indexes to determine IS, all partitions of extracts showed anti-insulin resistance effects in diabetic rats. On the basis of our statistical analyzing, treating diabetic rats with all of the three extracts of S. persica decreased the elevated levels of alanine phosphatase, aspartate aminotransferase, and alanine transferase. Also, pathological changes in the liver tissue were reduced following treatment with the S. persica. In conclusion, our results give evidence that the S. persica extract, especially aqueous partition, has a healing effect on diabetes and can be considered as an alternative therapy for this disease.  相似文献   

11.
Inhibitors of alpha glucosidase have potential use in the treatment of diabetes mellitus. The stem extract of Tinospora cordifolia was evaluated for inhibition of the enzyme. The extract was also found to inhibit the salivary and pancreatic amylase and therefore can effectively reduce an increase in postprandial glucose level. The crude ethyl acetate, dichloromethane (DCM), chloroform and hexane extracts of Tinospora cordifolia were studied. 15 mg of the DCM extract was most effective in that showed 100 % inhibition of the alpha glucosidase whereas salivary amylase was inhibited to the extent of 75 % and pancreatic amylase to 83 %. On giving a maltose load of 2mg / g along with 0.3 mg / g body weight of the DCM Tinospora stem extract a decrease was revealed in the hyperglycemic shoot up in normal and diabetic animals by 50 and 58 % respectively as compared to the controls. The extract was found to inhibit alpha glucosidase in a non-competitive manner.  相似文献   

12.
Blood pressure and blood flow patterns were recorded from the carotid artery and aortae of a thick-bodied terrestrial snake (Crotalus adamanteus) and a thin-bodied arboreal species (Ahaetulla nasuta) anesthetized with ketamine hydrochloride. Hemodynamic stress induced by rotation resulted in pronounced changes in the blood flow patterns and pressure in C. adamanteus: rotation of A. nasuta produced changes of a similar type, but of a much lower magnitude. The markedly different responses of these two species, the baroreceptor reflexes of which were disrupted, suggest that morphological factors – such as differential gross cardiac displacement, or variation in the interaortic foramen – in addition to physiological factors, are important in determining a snake's ability to withstand hemodynamic stress. Accepted: 8 April 1997  相似文献   

13.
Forty days of orally feeding the aqueous E. ribes extract (100 and 200 mg/kg) to streptozotocin (40 mg/kg, iv, single dose) induced diabetic rats produced significant decrease in heart rate, systolic blood pressure, blood glucose, blood glycosylated hemoglobin, serum lactate dehydrogenase, creatine kinase and increase in blood glutathione levels as compared to pathogenic diabetic rats. Further, the extract significantly decreased the levels of pancreatic lipid peroxides and increased the levels of pancreatic superoxide dismutase, catalase and glutathione. The results suggest that aqueous E. ribes extract exhibits a significant blood glucose and blood pressure lowering potential. Further, it enhances endogenous antioxidant defense against free radicals produced under hyperglycaemic conditions, thereby, seemingly protects the pancreatic beta-cells against loss in streptozotocin induced diabetic rats.  相似文献   

14.
沙生柽柳扦插生根过程插穗相关理化特征分析   总被引:1,自引:0,他引:1  
选取沙生柽柳半木质化枝条进行苗床扦插,通过实验测定插穗生根过程中内源激素(IAA、GA3、ZR、ABA)含量、可溶性营养物质(糖、蛋白质)含量及相关氧化酶(PPO、POD、SOD、IAAO)活性的动态变化特征,探讨沙生柽柳插穗扦插生根机理。结果表明:(1)沙生柽柳插穗内源激素含量随生根进程而发生变化,其中,IAA含量在扦插35d最大,并出现较大的波动变化;ZR含量在扦插55d前后变化明显,呈现低水平向高水平转化趋势;ABA、GA3含量依次呈先升高后降低再升高的变化过程,并在扦插15d和55d(80d)呈现变化的峰值和谷值。(2)沙生柽柳扦插生根与相关氧化酶活性密切相关,其中,POD、IAAO活性在插穗扦插35d后长时间保持较高水平,直至插穗生根后POD活性明显降低,IAAO活性有所增加;PPO、SOD活性则在插穗扦插15d保持较高活性,且PPO活性的变化均匀,SOD活性的高低交替变化明显。(3)在沙生柽柳扦插生根期间,插穗可溶性糖含量呈现生根前消耗减少与生根后积累增加两大变化过程,可溶性蛋白质含量表现为扦插后逐步积累增加的变化趋势。研究表明,高水平的IAA、ZR和低水平的GA3、ABA共同调控着沙生柽柳插穗生根;IAA能够通过促进插穗POD、PPO、IAAO活性变化来影响生根,较高的POD、IAAO活性可调节插穗IAA水平,高水平的PPO活性则催化插穗IAA-酚酸复合物的形成,进而诱导插穗生根。  相似文献   

15.
Differentiation of the pancreatic islets in grass snake Natrix natrix embryos, was analyzed using light, transmission electron microscopy, and immuno-gold labeling. The study focuses on the origin of islets, mode of islet formation, and cell arrangement within islets. Two waves of pancreatic islet formation in grass snake embryos were described. The first wave begins just after egg laying when precursors of endocrine cells located within large cell agglomerates in the dorsal pancreatic bud differentiate. The large cell agglomerates were divided by mesenchymal cells thus forming the first islets. This mode of islet formation is described as fission. During the second wave of pancreatic islet formation which is related to the formation of the duct mantle, we observed four phases of islet formation: (a) differentiation of individual endocrine cells from the progenitor layer of duct walls (budding) and their incomplete delamination; (b) formation of two types of small groups of endocrine cells (A/D and B) in the wall of pancreatic ducts; (c) joining groups of cells emerging from neighboring ducts (fusion) and rearrangement of cells within islets; (d) differentiated pancreatic islets with characteristic arrangement of endocrine cells. Mature pancreatic islets of the grass snake contained mainly A endocrine cells. Single B and D or PP–cells were present at the periphery of the islets. This arrangement of endocrine cells within pancreatic islets of the grass snake differs from that reported from most others vertebrate species. Endocrine cells in the pancreas of grass snake embryos were also present in the walls of intralobular and intercalated ducts. At hatching, some endocrine cells were in contact with the lumen of the pancreatic ducts.  相似文献   

16.
Diluted cane molasses having total sugar and reducing sugar content of 9.60 and 3.80% (w/v) respectively was subjected to ethanol production by Saccharomyces cerevisiae MTCC 178. Incorporation of dried Cauliflower Waste (CW) in molasses at the level of 15 % increased ethanol production by nearly 36 % compared to molasses alone. Addition of 0.2 % yeast extract improved ethanol production by nearly 49 % as compared to molasses alone. When the medium containing diluted molasses and 0.2 % yeast extract was supplemented with 15 % CW, 29 % more ethanol was produced compared to molasses with 0.2 % yeast extract. Cell biomass, ethanol production, final ethanol concentration and fermentation efficiency of 2.65 mg mL−1, 41.2 gL−1, 0.358 gg−1 and 70.11 % respectively were found to be best at 15% CW supplementation level besides reduction in fermentation time but further increase in CW level resulted in decline on account of all the above parameters. This is probably the first report to our knowledge, in which CW was used in enhancing ethanol production significantly using a small quantity of yeast extract.  相似文献   

17.
The sequence of histological changes in the regional lymph node and other lymphoid organs of mice injected with the capsular polysaccharide of Klebsiella pneumoniae (CPS-K) or bacterial lipopolysaccharide (LPS) was followed. Injection of CPS-K, but not LPS, induced the following characteristic histological changes in the regional lymph node. In the early stage there was a marked decrease in the number of small lymphocytes, accompanied by the appearance of scattered fragmented nuclei and infiltration of polymorphonuclear neutrophilic leukocytes, and in the late stage there was marked proliferation of macrophage-like cells and pyroninophilic cells. Histological changes in the thymus and spleen and changes in cell populations in the bone marrow and peripheral blood after CPS-K injection were essentially the same as after LPS injection. Since CPS-K has a much stronger adjuvant action on antibody response than does LPS, it is suggested that the characteristic histological changes in the regional lymph node after injection of CPS-K are closely related to its extraordinarily strong adjuvant action.  相似文献   

18.
The whole plant aqueous extract of E. littorale was tested for its hypoglycemic activity on normoglycemic, hyperglycemic and alloxan induced diabetic rats. Blood sugar lowering activity was not observed in normoglycemic and glucose loaded hyperglycemic rats in the short time experiment. But in case of diabetic rats, the fall of blood sugar after 30 days treatment with the aqueous extract was found to be significant (P < 0.001). The decrease in the plasma glucose level was accompanied with decrease in the level of glycosylated haemoglobin and glucose-6-phosphatase activity in liver. The potent anti-diabetic properties of E. littorale has been reported for the first time.  相似文献   

19.
Objective: Sustained exposure to lipids is deleterious for pancreatic islet function. This could be mediated through increased pancreatic fat following increased dietary fat and in obesity, which has implications for the onset of type 2 diabetes. The aims of this study were to determine changes in extent and composition of pancreatic, hepatic, and visceral fat in mice fed a high‐fat diet (HFD, 40% by weight) compared with a control diet (5% fat) of similar fatty acid composition, and to compare composition and extent of pancreatic fat in human type 2 diabetes. Methods and Procedures: Mice were fed HFD for 3 or 15 weeks. Human postmortem pancreas was examined from subjects with type 2 diabetes (n = 9) and controls (n = 7). Tissue lipid content and composition were determined by gas chromatography and pancreatic adipocyte infiltration quantified by morphometry. Results: Pancreatic triacylglycerol (TG) content was 20× greater (P < 0.05) in HFD mice and there were more pancreatic perilipin‐positive adipocytes compared with controls after 15 weeks. The proportions of 18:1n ?9 and 18:2n ?6 in pancreatic TG and the 20:4n ?6/18:2n ?6 ratio in phospholipids, were higher (both P < 0.05) after HFD compared with controls. Human pancreatic TG content was correlated with the proportion of pancreatic perilipin‐positive adipocytes (r = 0.64, P < 0.05) and associated with unsaturated fatty acid enrichment (P < 0.05). Discussion: Adipocyte infiltration in pancreatic exocrine tissue is associated with high‐fat feeding in mice and pancreatic TG content in humans. This alters the fatty acid milieu of the islet which could contribute to islet dysfunction.  相似文献   

20.
We studied the influence of the laccase activity of two white-rot fungi on the toxic effect of water-soluble substances from dry residues of olives (ADOR) on tomato plants. Pycnoporus cinnabarinus and Coriolopsis rigida decreased the phenol content of ADOR to 73% after 15 days. P. cinnabarinus and C. rigida produced laccase activity after 5 and 15 days, respectively, and the highest activity in both fungi was detected at 20 days. The treatment of ADOR with these white-rot fungi decreased the phytotoxicity of this residue on tomato plants. A close relationship was found between the amount of laccase produced, the decrease in phenol content of ADOR by the saprobic fungi, decrease of phytotoxicity of ADOR, and the increase in dry weight of tomato plants. These results show that phenol removal by the laccase activity of white-rot fungi can be important in the elimination of phytotoxic substances present in olive-mill dry residues.  相似文献   

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