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151.
A F Milne J N Williams F B Rudolph 《Comparative biochemistry and physiology. B, Comparative biochemistry》1978,59(3):199-200
The specific activity of the lysosomal enzyme N-acetyl-beta-D-hexosaminidase was determined in the caput and cauda of the epididymis of rats as a function of age. The activity peaks at six weeks of age in both parts of the epididymis but is higher in the cauda. The results indicate a relationship between changes occurring in sperm in the epididymis and the lysosomal enzymes. 相似文献
152.
Bidhan Bhuson Roy Rubel Biswas Chowdhury Amit Robert Baroi Shupa Rahman Stephen M. Powers Nick Milne Mohammad Sujauddin 《Journal of Industrial Ecology》2019,23(6):1439-1455
Phosphorus (P) is central to food production. Current understanding about the global phosphorus system is dominated by studies in wealthier nations where soil fertility, fertilizer supply chains, and agronomic tracking have long been established. In contrast, developing nations are experiencing major agricultural transitions and the associated phosphorus flows remain a significant knowledge gap. We compiled and analyzed several years of recent agricultural datasets for Bangladesh, currently the eighth most populous nation, using substance flow analysis for phosphorus. From 2000 to 2016, rice production increased by >50% and remained the dominant crop with remarkably higher phosphorus flow (49.96 kt in 2016) than all other crops. Phosphorus content of livestock products in 2016 exceeded 6.00 kt, more than double in the year 2000, driven primarily by phosphorus in milk and secondarily in meat/eggs. These agricultural changes coincided with a doubling of national phosphorus fertilizer consumption since 2000, a fourfold increase since the global food crisis (2009), and a pronounced rise in the phosphorus import dependency ratio, which was the highest among all countries compared. In turn, during 2010s fertilizer phosphorus use exceeded phosphorus as food + feed production leading to soil phosphorus accumulation, and loss as burned manure became one of the largest phosphorus flows in the entire system, equivalent to half of fertilizer use. This dramatic reconfiguration of the Bangladesh phosphorus system illustrates an important case of agricultural expansion and intensification that is still playing out, with similar situations occurring in developing nations where population growth rates are high, and access to commercial fertilizers has risen. 相似文献
153.
Zopiclone is a poorly soluble psychotherapeutic agent. The aim of this study was to prepare and characterize an amorphous form of zopiclone as well as the characterization and performance of a stable amorphous solid dispersion. The amorphous form was prepared by the well-known method of quench-cooling of the melt. The solid dispersion was prepared by a solvent evaporation method of zopiclone, polyvinylpyrrolidone-25 (PVP-25), and methanol, followed by freeze-drying. The physico-chemical properties and stability of amorphous zopiclone and the solid dispersion was studied using differential scanning calorimetry (DSC), infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), hot-stage microscopy (HSM), X-ray diffractometry (XRD), solubility, and dissolution studies. The zopiclone amorphous solid-state form was determined to be a fragile glass; it was concluded that the stability of the amorphous form is influenced by both temperature and water. Exposure of amorphous zopiclone to moisture results in rapid transformation of the amorphous form to the crystalline dihydrated form. In comparison, the amorphous solid dispersion proved to be more stable with increased aqueous solubility.KEY WORDS: amorphous, fragile, solid dispersion, stability, zopiclone 相似文献
154.
In the overnourished adolescent sheep, maternal tissue synthesis is promoted at the expense of placental growth and leads to a major decrease in lamb birth weight at term. Maternal growth hormone (GH) concentrations are attenuated in these pregnancies, and it was recently demonstrated that exogenous GH administration throughout the period of placental proliferation stimulates uteroplacental and fetal development by Day 81 of gestation. The present study aimed to determine whether these effects persist to term and to establish whether GH affects fetal growth and body composition by increasing placental size or by altering maternal metabolism. Adolescent recipient ewes were implanted with singleton embryos on Day 4 postestrus. Three groups of ewes offered a high dietary intake were injected twice daily with recombinant bovine GH from Days 35 to 65 of gestation (high intake plus early GH) or from Days 95 to 125 of gestation (high intake plus late GH) or remained untreated (high intake only). A fourth moderate-intake group acted as optimally nourished controls. Pregnancies were terminated at Day 130 of gestation (6 per group) or were allowed to progress to term (8-10 per group). GH administration elevated maternal plasma concentrations of GH, insulin, glucose, and nonesterified fatty acids during the defined treatment windows, while urea concentrations were decreased. At Day 130, GH treatment had reduced the maternal adiposity score, percentage of fat in the carcass, and internal fat depots and leptin concentrations, predominantly in the high-intake plus late GH group. Placental weight was lower in high-intake vs. control dams but independent of GH treatment. In contrast, fetal weight was elevated by late GH treatment, and these fetuses had higher relative carcass fat content, perirenal fat mass, and liver glycogen concentrations than all other groups. Expression of leptin mRNA in fetal perirenal fat and fetal plasma leptin concentrations were not significantly altered by maternal nutritional intake or GH. In pregnancies proceeding to term, the duration of gestation, fetal placental mass, and lamb birth weight were reduced in high-intake compared with control dams but were not significantly affected by GH treatment. In conclusion, exogenous GH has profound effects on maternal endocrinology, metabolism, and body composition when administered during early and late pregnancy. Treatment during late pregnancy has a modest effect on fetal growth independent of placental size and a profound effect on fetal adiposity, which may have implications beyond the fetal period. 相似文献
155.
Ribas G González-Neira A Salas A Milne RL Vega A Carracedo B González E Barroso E Fernández LP Yankilevich P Robledo M Carracedo A Benítez J 《Human genetics》2006,118(6):669-679
One of the many potential uses of the HapMap project is its application to the investigation of complex disease aetiology
among a wide range of populations. This study aims to assess the transferability of HapMap SNP data to the Spanish population
in the context of cancer research. We have carried out a genotyping study in Spanish subjects involving 175 candidate cancer
genes using an indirect gene-based approach and compared results with those for HapMap CEU subjects. Allele frequencies were
very consistent between the two samples, with a high positive correlation (R) of 0.91 (P<<1×10−6). Linkage disequilibrium patterns and block structures across each gene were also very similar, with disequilibrium coefficient
(r
2) highly correlated (R=0.95, P<<1×10−6). We found that of the 21 genes that contained at least one block larger than 60 kb, nine (ATM, ATR, BRCA1, ERCC6, FANCC, RAD17, RAD50, RAD54B and XRCC4) belonged to the GO category “DNA repair”. Haplotype frequencies per gene were also highly correlated (mean R=0.93), as was haplotype diversity (R=0.91, P<<1×10−6). “Yin yang” haplotypes were observed for 43% of the genes analysed and 18% of those were identical to the ancestral haplotype
(identified in Chimpazee). Finally, the portability of tagSNPs identified in the HapMap CEU data using pairwise r
2 thresholds of 0.8 and 0.5 was assessed by applying these to the Spanish and current HapMap data for 66 genes. In general,
the HapMap tagSNPs performed very well. Our results show generally high concordance with HapMap data in allele frequencies
and haplotype distributions and confirm the applicability of HapMap SNP data to the study of complex diseases among the Spanish
population.
Electronic Supplementary Material Supplementary material is available for this article at and is accessible for authorized users. 相似文献
156.
Nguyen AT Braschi S Geoffrion M Fong LG Crooke RM Graham MJ Young SG Milne R 《Biochimica et biophysica acta》2006,1761(2):182-185
We have generated and characterized a murine monoclonal antibody (mAb) that binds to both mouse apolipoprotein (apo) B48 and apoB100. We immunized "apoB39-only" mice (mice that synthesize a truncated form of apoB, apoB39, but no apoB48 or apoB100) with lipoproteins containing mouse apoB48 and then used splenocytes from the immunized mice to create hybridomas. We identified a hybridoma, 2G11, that secretes a mAb that binds to mouse apoB48 and apoB100 but not to apoB39. Antibody 2G11 also binds apoB48 and apoB100 from rats and hamsters but not from humans. The mAb recognizes mouse apoB equally in very low and low density lipoproteins and was used to quantify apoB in wild-type, apoE-deficient and low-density lipoprotein receptor-deficient mice and in mice treated with an antisense drug that lowers plasma apoB levels. The antibody will be an important reagent for studying mouse models of atherosclerosis. The study also underscores the utility of genetically modified mice for generating mouse mAbs against mouse proteins. 相似文献
157.
Biochemical characterization,localization, and tissue distribution of the longer form of mouse SIRT3
Lei Jin Heidi Galonek Kristine Israelian Wendy Choy Michael Morrison Yu Xia Xiaohong Wang Yihua Xu Yuecheng Yang Jesse J. Smith Ethan Hoffmann David P. Carney Robert B. Perni Michael R. Jirousek Jean E. Bemis Jill C. Milne David A. Sinclair Christoph H. Westphal 《Protein science : a publication of the Protein Society》2009,18(3):514-525
SIRT3 is a key mitochondrial protein deacetylase proposed to play key roles in regulating mitochondrial metabolism but there has been considerable debate about its actual size, the sequences required for activity, and its subcellular localization. A previously cloned mouse SIRT3 has high sequence similarity with the C‐terminus of human SIRT3 but lacks an N‐terminal mitochondrial targeting sequence and has no detectable deacetylation activity in vitro. Using 5′ rapid amplification of cDNA ends, we cloned the entire sequence of mouse SIRT3, as well as rat and rabbit SIRT3. Importantly, we find that full‐length SIRT3 protein localizes exclusively to the mitochondria, in contrast to reports of SIRT3 localization to the nucleus. We demonstrate that SIRT3 has no deacetylation activity in vitro unless the protein is truncated, consistent with human SIRT3. In addition, we determined the inhibition constants and mechanism of action for nicotinamide and a small molecule SIRT3 inhibitor against active mouse SIRT3 and show that the mechanisms are different for the two compounds with respect to peptide substrate and NAD+. Thus, identification and characterization of the actual SIRT3 sequence should help resolve the debate about the nature of mouse SIRT3 and identify new mechanisms to modulate enzymatic activity. 相似文献
158.
Jean E. Bemis Chi B. Vu Roger Xie Joseph J. Nunes Pui Yee Ng Jeremy S. Disch Jill C. Milne David P. Carney Amy V. Lynch Lei Jin Jesse J. Smith Siva Lavu Andre Iffland Michael R. Jirousek Robert B. Perni 《Bioorganic & medicinal chemistry letters》2009,19(8):2350-2353
SIRT1 is an NAD+-dependent protein deacetylase that appears to produce beneficial effects on metabolic parameters such as glucose and insulin homeostasis. Activation of SIRT1 by resveratrol (1) has been shown to modulate insulin resistance, increase mitochondrial content and prolong survival in lower organisms and in mice on a high fat diet. Herein, we describe the identification and SAR of a series of oxazolo[4,5-b]pyridines as novel small molecule activators of SIRT1 which are structurally unrelated to and more potent than resveratrol. 相似文献
159.
Ralton LD Bestwick CS Milne L Duthie S Kong Thoo Lin P 《Chemico-biological interactions》2009,177(1):1-6
Bisnaphthalimido compounds bisintercalate to DNA via the major groove and are potentially potent cancer therapeutics. We incorporated natural polyamines as linkers connecting the two-naphthalimido ring moieties to create a series of novel soluble cytotoxic bisnaphthalimidopropyl polyamines (BNIPPs). Here, we determined the cytotoxicity of bisnaphthalimidopropyl spermidine (BNIPSpd) towards Caco-2 and HT-29 colon adenocarcinoma cells revealing an IC50 value of 0.15 and 1.64 μM after 48 h exposure within Caco-2 and HT-29 cells, respectively. After 4 h, ≥0.5 μM BNIPSpd treatment-induced significant DNA damage. After 24 h exposure a concentration-dependent increase in active caspase-3 expression, chromatin condensation and internucleosomal DNA fragmentation identified apoptosis as the principal manifestation for the cytotoxicity within both cell lines. By 24 h exposure, there was also a significant decline in cellular spermine and spermidine levels. It is concluded that bisnaphthalimidopropyl spermidine (BNIPSpd) toxicity primarily results from apoptosis and that BNISpd has potential to be further developed as an anti-tumour agent. 相似文献
160.
We examine the relationship between birth order and reproductive behaviors in a sample of Australian residents, accounting
for personality, personal achievements, and family structure. Using generalized linear models and survival analyses we build
predictive models for each reproductive measure and test those models on an independent data subset. Compared with functional
firstborns (middle-borns more than 5 years younger than their next older sibling), male middle-borns and last-born females
had younger ages of first sexual intercourse, and middle-born females had a younger age at first pregnancy. There was no difference
in females’ age at first birth. Male middle-borns tended to have an older average age at first birth. Controlling for age,
both male and female middle-borns had fewer children. Overall, middle-borns differ more from functional firstborns than do
last-borns. Given the significant but small effect sizes demonstrated in this study, we suggest that developmental characteristics
that may facilitate middle-borns’ success within the natal family carry slight fitness costs during the reproductive years.
相似文献
Fritha MilneEmail: |