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排序方式: 共有725条查询结果,搜索用时 15 毫秒
1.
Radwan H. Ahmed Hasniza Zaman Huri Zaid Al-Hamodi Sameer D. Salem Sekaran Muniandy 《PloS one》2015,10(10)
BackgroundA soluble form of CD26/dipeptidyl peptidase-IV (sCD26/DPP-IV) induces DPP-IV enzymatic activity that degrades incretin. We investigated fasting serum levels of sCD26/DPP-IV and active glucagon-like peptide-1 (GLP-1) in Malaysian patients with type 2 diabetes mellitus (T2DM) with and without metabolic syndrome (MetS), as well as the associations between sCD26/DPP-IV levels, MetS, and antidiabetic therapy.MethodsWe assessed sCD26/DPP-IV levels, active GLP-1 levels, body mass index (BMI), glucose, insulin, A1c, glucose homeostasis indices, and lipid profiles in 549 Malaysian subjects (including 257 T2DM patients with MetS, 57 T2DM patients without MetS, 71 non-diabetics with MetS, and 164 control subjects without diabetes or metabolic syndrome).ResultsFasting serum levels of sCD26/DPP-IV were significantly higher in T2DM patients with and without MetS than in normal subjects. Likewise, sCD26/DPP-IV levels were significantly higher in patients with T2DM and MetS than in non-diabetic patients with MetS. However, active GLP-1 levels were significantly lower in T2DM patients both with and without MetS than in normal subjects. In T2DM subjects, sCD26/DPP-IV levels were associated with significantly higher A1c levels, but were significantly lower in patients using monotherapy with metformin. In addition, no significant differences in sCD26/DPP-IV levels were found between diabetic subjects with and without MetS. Furthermore, sCD26/DPP-IV levels were negatively correlated with active GLP-1 levels in T2DM patients both with and without MetS. In normal subjects, sCD26/DPP-IV levels were associated with increased BMI, cholesterol, and LDL-cholesterol (LDL-c) levels.ConclusionSerum sCD26/DPP-IV levels increased in T2DM subjects with and without MetS. Active GLP-1 levels decreased in T2DM patients both with and without MetS. In addition, sCD26/DPP-IV levels were associated with Alc levels and negatively correlated with active GLP-1 levels. Moreover, metformin monotherapy was associated with reduced sCD26/DPP-IV levels. In normal subjects, sCD26/DPP-IV levels were associated with increased BMI, cholesterol, and LDL-c. 相似文献
2.
The effect of tin and lead on levels of essential metals (Zn, Cu, Ca, Fe) in rabbit tissues was compared in relation to the route of administration. Animals received intraperitoneally, or per os, SnCl2 (2 mg Sn/kg) or Pb(CH3COO)2 (3.5 mg Pb/kg) every day for 5 d or for 1 mo. Copper, zinc, iron, and calcium were determined by AAS in the liver, kidneys, spleen, brain, bone marrow, and blood; lead and tin concentration were measured in the blood of animals. Tin and lead administered per os caused either no changes or the decreased concentration of endogenous metals in several tissues. The other route of administration (ip) of both metals generally contributed to the increased storage of essential elements. Blood tin levels of tin treated animals were only about less than or equal to 1/10 of blood lead concentrations of rabbits exposed to lead. 相似文献
3.
Redha H. Al-Hasan Feras M. Hantash Samir S. Radwan 《Applied microbiology and biotechnology》1991,35(4):530-535
Summary Twelve macroalgae belonging to the Chlorophyta, Phaeophyta and Rhodophyta were collected from the Arabian Gulf. Field samples and samples that were first incubated at 5° C and 24° C in the light for 1 week were analysed for lipids and fatty acids. The lipid contents varied according to the macroalga and, within the Chlorophyta and Phaeophyta, some representatives accumulated more lipids at 5° C and others at 24° C. All samples of algae had similar lipid composition with only quantitative differences. The temperature did not have a common effect on the lipid composition of representative algae, although changes in the relative concentration of specific classes were recorded. The Phaeophyta and Rhodophyta were as a rule richer than the Chlorophyta in eicosatetranoic (20:4) and eicosapentaenoic (20:5) but poorer in linolenic (18:3) acids. In most of the algae, incubation at 5° C was associated with lowering the proportion of palmitic acid (16:0) in the total lipids, and, but only in the Phaeophyta and Rhodophyta, increasing the concentration of 20:4 and 20:5. These polyunsaturated fatty acids occurred in high levels in monogalactosyldiacylglycerols (MGDG) and digalactosyldiacylglycerols (DGDG) of the Phaeophyta and Rhodophyta but not the Chlorophyta, the MGDG and DGDG of which were rich in 18:3 and hexadecatrienoic acid (16:3).
Offprint requests to: R. H. Al-Hasan 相似文献
4.
Jadwiga Jaruzelska Karen Friis Henriksen Flemming Güttler Olaf Riess Krzysztof Borski Nikolaus Blin Ryszard Slomski 《Human genetics》1991,86(3):247-250
Summary The incidence of phenylketonuria (PKU) in the western part of Poland is 1 in 5000 live births. Restriction fragment length polymorphism (RFLP) haplotypes at the phenylalanine hydroxylase locus have been analysed in 46 Polish families with PKU. Among 43 fully-informative families 16 RFLP haplotypes were identified. Haplotype 2 is the most frequently (62%) associated with Polish PKU alleles, and the codon 408 mutation is in complete linkage disequilibrium with this haplotype in Poland. This finding is in agreement with observations in other eastern European countries (German Democratic Republic, Czechoslovakia, and Hungary) and in contrast to the genotype distribution observed in western European countries. The present observation suggests the spread of classical PKU, due to the codon 408 mutation associated with haplotype 2, from east to west in European populations. Perhaps more important for genetic counselling, 62% of all PKU chromosomes in the Polish population can now be detected using only one mutantspecific oligonucleotide probe. 相似文献
5.
Ashok K. Raina Timothy G. Kingan Jadwiga M. Giebultowicz 《Archives of insect biochemistry and physiology》1994,25(4):317-327
Mating in most species of insects leads to a transient or permanent loss in sexual receptivity of the females. Among moths, this loss of receptivity is often accompanied with a loss of the sex pheromone in the absence of calling, which also could be temporary or permanent. Most of the earlier work on changes in reproductive behavior after mating was done with Diptera in which sperm and/or male accessory gland secretions were shown to be responsible for termination of receptivity. In the corn earworm moth, Helicoverpa zea, mated females become depleted of pheromone and become nonreceptive to further mating attempts, but only for the remainder of the night of mating. A pheromonostatic peptide isolated from the accessory glands of males may be responsible for the depletion of pheromone, while the termination of receptivity is independently controlled. In the gypsy moth, Lymantria dispar, the changes in behavior following mating are permanent. In this species, the switch from virgin to mated behavior involves three steps: a physical stimulation associated with mating, transfer of viable sperm to the spermatheca, and commencement of oviposition. Signals generated by these factors operate through neural pathways and, unlike in H. zea, accessory gland factors seem not to be involved. © 1994 Wiley-Liss, Inc. 1 This article is a US Government work and, as such, is in the public domain in the United States of America. 相似文献
6.
S.S. Radwan N.A. Sorkhoh H. Felzmann A.F. El-Desouky 《Journal of applied microbiology》1996,80(4):370-374
Arthrobacter nicotianae KCC B35 isolated from blue-green mats densely covering oil sediments along the Arabian Gulf coast grew well on C10 to C40 n -alkanes as sole sources of carbon and energy. Growth on C20 to C40 alkanes was even better than on C10 to C18 alkanes. Biomass samples incubated for 6 h with n -octacosane (C28 ) or n -nonacosane (C29 ) accumulated these compounds as the predominant constituent alkanes of the cell hydrocarbon fractions. The even chain hexadecane C16 and the odd chain pentadecane C15 were the second dominant constituent alkanes in C28 and C29 incubated cells, respectively. n -Hexadecane-incubated cells accumulated in their lipids higher proportions of C16 -fatty acids than control cells not incubated with hydrocarbons. On the other hand, C28 and C29 -incubated cells did not contain any fatty acids with the equivalent chain lengths, but the fatty acid patterns of the cell lipids suggest that there should have been mid-chain oxidation of these very long chain alkanes. This activity qualifies A. nicotianae KCC B35 to be used in cocktails for bioremediating environments polluted with heavy oil sediments. 相似文献
7.
Marek S. Zie¸tara Jadwiga Gronczewska Krystyna Stachowiak Edward F. Skorkowski 《Comparative biochemistry and physiology. Part B, Biochemistry & molecular biology》1996,114(4):395-401
In crayfishOrconectes limosus and shrimpCrangon crangon abdominal muscle, lactate dehydrogenase (LDH, EC 1.1.1.27) is encoded by one locus. No polymorphism was detected. The enzymes were purified to homogeneity. The specific activities for purified crayfish and shrimp LDHs were 472 and 414 μmol NADH min−1 mg−1, respectively, at 30°C. Their physicochemical and kinetic properties did not resemble fish (Gadus morhua) LDH-A4 isoenzyme. Their amino acid composition indicated greater similarity to fish LDH-C4 isoenzymes. 相似文献
8.
S. S. Radwan N. A. Sorkhoh F. Fardoun R. H. Al-Hasan 《Applied microbiology and biotechnology》1995,44(1-2):265-270
Oil-polluted Kuwaiti desert samples, exposed to the open air, were subjected to specific types of management, once every 2 weeks, throughout a year; control samples were not treated. The total amounts of extractable alkanes from the control samples remained fairly constant during the dry hot months, but decreased during the rainy months reaching, after 1 year, slightly more than one-half of the amount at zero time. This result demonstrates the self-cleaning of the Kuwaiti desert and the essential role of moisture in this process. Out of the eight types of management studied, the repeated fertilization of the polluted sample with 3% KNO3 solution was most efficient, reducing the extractable alkanes after 1 year to about one-third of zero reading. Repeated fertilization with treated sewage effluent was inhibitory to alkane biodegradation, probably because of increasing soil acidity. The latter inhibitory effect was annulled by liming. Repeated irrigation with 3% NaCl solution was inhibitory, but 1% NaCl solution slightly promoted alkane biodegradation. The various samples contained 1010–1011 oil-utilizing bacteria/g soil, predominantly Bacillus, Pseudomonas, Rhodococcus and Streptomyces. Oil-utilizing fungi were much less frequent and were predominantly Aspergillus and Penicillium species. The microbial numbers varied not only according to the type of soil management but also to the season. 相似文献
9.
Callus cultures of Trigonella foenum-graecum contained 3 to 4 times more trigonelline than the seeds of this plant and 12 to 13 times more than the roots and shoots. Even higher levels of this alkaloid were produced by suspension cultures. This high productivity was maintained during successive subculturing of calli and cell suspensions for eight months. Thus, trigonelline is to be added to the group of the few metabolites whose synthesis in cell cultures exceeds its production in the differentiated plants. Media that had supported the growth of suspension cultures contained one third or more of the total alkaloid, whereas media of callus cultures contained about one tenth of this substance. Trigonelline accumulated in callus and suspension cultures with aging. Raising the level of nicotinic acid in the nutrient medium resulted in some increase of trigonelline production by the culture.Abbreviations 2.4 D
2.4-dichlorophenoxyacetic acid
- IAA
indoleacetic acid
- IPA
indolepropionic acid
- NAA
-naphthaleneacetic acid
- GA
Gibberellic acid
- K
kinetin 相似文献
10.
Andrzej J. Żelazowski Jadwiga A. Szymańska Czesklaw S. Cierniewski 《Chemico-biological interactions》1980,33(1):115-125
Two homogenous fractions of hepatic metallothioneins ((Cd,Zn) MT-1 and (Cd,Zn) MT-2) and renal metal binding proteins ((Bi,Cu) BP-1 and (Bi,Cu) BP-2) were isolated from rats exposed to heavy metals and specific antisera to them were produced in rabbits.These antisera were tested by immunodiffusion and immunoelectrophoresis for their ability to bind different fractions of hepatic Cd,Zn -metallothionein and renal (Bi,Cu)-, (Hg,Cu)- and (Cd,Cu)-binding proteins. It was found that anti (Bi,Cu) BP antisera did not cross-react with hepatic (Cd,Zn) MT-1 and (Cd,Zn) MT-2. Strong immunological cross-reactions were detected between anti (Bi,Cu) BP antisera and individual forms of (Cd,Cu)-, (Hg,Cu)- and (Bi,Cu)-binding proteins isolated from rat kidneys. 相似文献