121 research outputs found
FIELD MEASUREMENT AND MODELLING OF THE MATERIAL CYCLE IN THE CULTIVATION POND OF PENAEID SHRIMP PENAEUS JAPONICUS
ABSTRACT Field measurement and modelling of the material cycle are carried out for the cultivation pond of penaeid shrimp Penaeus japonicus. The main purpose of the present study is to investigate the sustainability of coastal shrimp aquaculture, which is increasingly being questioned due to many problems like disease, excessive nutrient enrichment, and low levels of dissolved oxygen tension. Despite the great economic importance of shrimps and their suitability to aquaculture, little is known about the material cycle through the cultivation pond. Additionally, the collapse of shrimp aquaculture in most tropical countries may be attributed to the lack of ecological, biological, and environmental understanding. Hence field measurement of water quality is conducted in the shrimp cultivation pond, which locates in the Kyushu district of Japan. Various environmental factors such as water temperature, salinity, and the concentrations of dissolved oxygen, nutrients, and chlorophyll a are monitored for the water in the pond and that drawn from the outer sea during November and December of 2006. In addition to field measurement, one dimensional numerical model is developed for the shrimp cultivation pond to understand the material cycle through the pond in a quantitative manner. The numerical model consists of physical, lower trophic-level ecosystem, and shrimp growth submodels. The numerical values of physical and physiological parameters are calibrated to achieve the best agreement between observed and simulated results. By integrating results from field measurement and numerical simulation, it is revealed that the quality of water in the cultivation pond is quite different from that drawn from the outer sea. In particular the concentration of chlorophyll a is much higher in the cultivation pond due to large primary production. The results of the numerical simulation show that the high productivity is attributed partly to the activities of shrimps. The information from field measurement and the simulated results of the developed numerical model are useful to optimize the food quantity and quality, the population density of shrimps, and the design of watermills or the other equipments to improve the water quality for sustainable use of coastal shrimp cultivation pond
Cellular DBP and E4BP4 proteins are critical for determining the period length of the circadian oscillator
AbstractThe phenotypes of mice carrying clock gene mutations have been critical to understanding the mammalian clock function. However, behavior does not necessarily reflect cell-autonomous clock phenotypes, because of the hierarchical dominance of the central clock. We performed cell-based siRNA knockdown and cDNA overexpression and monitored rhythm using bioluminescent reporters of clock genes. We found that knockdown of DBP, D-box positive regulator, in our model led to a short-period phenotype, whereas overexpressing of DBP produced a long-period rhythm when compared to controls. Furthermore, knockdown and overexpressing of E4BP4, D-box negative regulator, led to an opposite effect of DBP. Our experiments demonstrated that D-box regulators play a crucial role in determining the period length of Per1 and Per2 promoter-driven circadian rhythms in Rat-1 fibroblasts
Successful conservative treatment for massive uterine bleeding with non-septic disseminated intravascular coagulation after termination of early pregnancy in a woman with huge adenomyosis: case report.
BACKGROUND:Adenomyosis is a benign gynecological condition in which endometrial tissue or endometrial-like tissue develops within the uterine myometrium. Few cases of disseminated intravascular coagulation has been reported in the patients with adenomyosis. Although hysterectomy is indicated for refractory massive uterine bleeding in the patients with advanced uterine adenomyosis, conservative treatment is often desired in women in the late reproductive age. Recently such cases are increasing due to the social trend of late marriage.CASE PRESENTATION:A 37-year-old woman with huge adenomyosis, gravida 2 para 0, was referred to our hospital to terminate her pregnancy. Acute, non-septic, disseminated intravascular coagulation (DIC) developed after early pregnancy was terminated in a woman with huge adenomyosis. Massive bleeding and DIC occurred 3 days after the dilatation and curettage. There was no evidence of infection as the cause of the DIC, because neither bacteria nor endotoxin could be detected in her blood, and antithrombin 3 (AT3), which would be expected to decrease in septic patients, was not decreased. Hemorrhage in the adenomyotic tissue after the termination presumably developed inflammation, with numerous microthrombi and necrosis in the adenomyotic tissue, which subsequently promoted coagulation and fibrinolysis, leading to the onset of massive uterine bleeding and DIC. Although severe hyperfibrinolysis is observed in peripheral blood, the fibrinolysis state in the uterine myometrium is considered to be even more severe. The newly formed clots for hemostasis under the uterine mucosa could be removed due to the excessive activation of fibrinolytic system happened in the adjacent myometrium, leading to the onset of massive uterine bleeding. Massive bleeding and DIC resolved quickly after the patient was treated with nafamostat mesilate, which is effective for both excessive coagulation and fibrinolysis.CONCLUSIONS:Adenomyosis could cause massive bleeding and DIC when pregnancy is terminated. Massive bleeding was considered to occur because the excessive fibrinolysis system inside adenomyosis affected the adjacent endometrium. Before considering hysterectomy to control refractory uterine bleeding, nafamostat mesilate should be considered as one option, thinking the pathophysiology of the massive bleeding due to uterine adenomyosis
Serotonin Improves High Fat Diet Induced Obesity in Mice
There are two independent serotonin (5-HT) systems of organization: one in the central nervous system and the other in the periphery. 5-HT affects feeding behavior and obesity in the central nervous system. On the other hand, peripheral 5-HT also may play an important role in obesity, as it has been reported that 5-HT regulates glucose and lipid metabolism. Here we show that the intraperitoneal injection of 5-HT to mice inhibits weight gain, hyperglycemia and insulin resistance and completely prevented the enlargement of intra-abdominal adipocytes without having any effect on food intake when on a high fat diet, but not on a chow diet. 5-HT increased energy expenditure, O2 consumption and CO2 production. This novel metabolic effect of peripheral 5-HT is critically related to a shift in the profile of muscle fiber type from fast/glycolytic to slow/oxidative in soleus muscle. Additionally, 5-HT dramatically induced an increase in the mRNA expression of peroxisome proliferator-activated receptor coactivator 1α (PGC-1α)-b and PGC-1α-c in soleus muscle. The elevation of these gene mRNA expressions by 5-HT injection was inhibited by treatment with 5-HT receptor (5HTR) 2A or 7 antagonists. Our results demonstrate that peripheral 5-HT may play an important role in the relief of obesity and other metabolic disorders by accelerating energy consumption in skeletal muscle
High-resolution photoelectron spectroscopy study of Kondo metals : SmSn3 and Sm0.9La0.1Sn3
We performed a high-resolution photoelectron spectroscopy study on the Kondo metals SmSn3 and Sm0.9La0.1Sn3. The experimental results are compared with calculations of density of state performed within the local density approximation plus the dynamical mean-field theory. The theory is found to reproduce the experimental valence-band spectra well. In both SmSn3 and Sm0.9La0.1Sn3 the bulk Sm valence is nearly trivalent, with a small fraction of divalent component. Resonant photoelectron spectroscopy indicates a decrease in the Kondo effect in the diluted system Sm0.9La0.1Sn3
Identification of functional clock-controlled elements involved in differential timing of Per1 and Per2 transcription
It has been proposed that robust rhythmic gene expression requires clock-controlled elements (CCEs). Transcription of Per1 was reported to be regulated by the E-box and D-box in conventional reporter assays. However, such experiments are inconclusive in terms of how the CCEs and their combinations determine the phase of the Per1 gene. Whereas the phase of Per2 oscillation was found to be the most delayed among the three Period genes, the phase-delaying regions of the Per2 promoter remain to be determined. We therefore investigated the regulatory mechanism of circadian Per1 and Per2 transcription using an in vitro rhythm oscillation-monitoring system. We found that the copy number of the E-box might play an important role in determining the phase of Per1 oscillation. Based on real-time bioluminescence assays with various promoter constructs, we provide evidence that the non-canonical E-box is involved in the phase delay of Per2 oscillation. Transfection experiments confirmed that the non-canonical E-box could be activated by CLOCK/BMAL1. We also show that the D-box in the third conserved segment of the Per2 promoter generated high amplitude. Our experiments demonstrate that the copy number and various combinations of functional CCEs ultimately led to different circadian phases and amplitudes
Clinical diagnostic value of telomere length measurement in inherited bone marrow failure syndromes
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