Chlorinated hydrocarbons are lipophilic, toxic, and persistent in the environment and animal tissues. They enter the body in food and are stored in adipose tissue. Loss of body fat through caloric restriction mobilizes stored lipophilic xenobiotics and results in distribution to other tissues. We have studied the reversibility of this process in mice that followed a regimen of body weight cycling. Weight gain was followed by weight loss, a second gain, and a second loss ("yo-yo diet regimen"). We measured the distribution of orally gavaged [14C]hexachlorobenzene, which is sparingly metabolized. We found that weight cycling has different effects in different organs. Continued weight loss resulted in a threefold increase of 14C amount and concentration in the brain. After weight regain, 14C in the brain decreased but then increased again after a second weight loss. Weight loss resulted in an increase in the concentration of 14C in adipose tissue without changing the total amount in that tissue. Weight loss and regain resulted in an increase of 14C in the liver, which reflected an increase of fat in the liver. The regimen of weight gain and loss was repeated in mice gavaged with [14C]hexachlorobenzene, with one group receiving the nonabsorbable fat olestra in the diet. Combined dietary olestra and caloric restriction caused a 30-fold increase in the rate of excretion of 14C relative to an ad libitum diet or a reduced caloric diet alone. Distribution of 14C into the brain resulting from the restricted diet was reduced by 50% by dietary olestra.
Apolipoprotein (apo) A-IV is a glycoprotein synthesized by the human intestine. In rodents, both the small intestine and the liver secrete apo A-IV; the small intestine, however, is by far the major organ responsible for the circulating apo A-IV. Intestinal apo A-IV synthesis is markedly stimulated by fat absorption and appears not to be mediated by the uptake or reesterification of fatty acids to form triglycerides. Rather, it is the formation of chylomicrons that acts as a signal for the induction of intestinal apo A-IV synthesis. Intestinal apo A-IV synthesis is also enhanced by a factor from the ileum and that factor is probably peptide tyrosine-tyrosine (PYY). The inhibition of food intake by apo A-IV is probably mediated centrally. The stimulation of intestinal synthesis and secretion of apo A-IV by lipid absorption are rapid; thus, apo A-IV likely plays a role in the short-term regulation of food intake. Other evidence suggests that apo A-IV may also be involved in the long-term regulation of food intake and body weight. Chronic ingestion of a high fat diet blunts the intestinal apo A-IV response to lipid feeding and may explain why the chronic ingestion of a high fat diet predisposes both animals and humans to obesity.
Apolipoprotein AIV (apo AIV) and cholecystokinin (CCK) are peptides that act both peripherally and centrally to reduce food intake by decreasing meal size. The present study examined the effects of intraperitoneally administered bolus doses of recombinant apo AIV, CCK-8, and a combination of subthreshold doses of apo AIV and CCK on 4-h food intake in rats that were fasted overnight. Apo AIV at 100 μg/kg reduced food intake significantly relative to the saline control for 1 h, as did doses of CCK-8 at or above 0.125 μg/kg. Doses of apo AIV (50 μg/kg) or CCK (0.06 μg/kg) alone had no effect on food intake. However, when these subthreshold doses of apo AIV and CCK were administered together, the combination produced a significant inhibition of food intake relative to saline controls ( P < 0.001), and the duration of the effect was longer than that caused by the administration of either apo AIV or CCK alone. The satiation effect produced by CCK-8 + apo AIV was attenuated by lorglumide, a CCK1 receptor antagonist. We conclude that, whereas the intraperitoneal administration of doses of either recombinant apo AIV or CCK at or above threshold levels reduces food intake, the coadministration of subthreshold doses of the two peptides is highly satiating and works via CCK1 receptor.
Malignant phyllodes tumor of the breast (MPTB) is rarely encountered in clinical practice. Preoperative diagnosis is challenging due to nonspecific radiological and histological features, and the prognostic factors and optimal treatment remain controversial. The current report describes the case of a middle-aged female with giant MPTB who underwent multidisciplinary intervention, including surgery, postoperative chemotherapy and radiotherapy. To date, the disease-free survival (DFS) of the patient has reached 18 months. Furthermore, a related literature review summarize the clinicopathological characteristics and treatment progress regarding MPTB is presented, along with an analysis of the indications for therapeutic strategy in the current case. In the future, multi-center clinical trials must be initiated to identify the criteria for diagnosis and optimal treatment consensus for MPTB. In conclusion, the present case highlights that multidisciplinary management may contribute to DFS following the treatment of giant MPTB.
Cell junctions serve as a protective barrier for cells and provide an important channel for information transmission between cells and the surrounding environment. Viruses are parasites that invade and commandeer components of host cells in order to survive and replicate, and they have evolved various mechanisms to alter cell junctions to facilitate viral infection. In this review, we examined the current state of knowledge on the action of viruses on host cell junctions. The existing evidence suggests that targeting the molecules involved in the virus‐cell junction interaction can prevent the spread of viral diseases.
The OSIRIS detector is a subsystem of the liquid scintillator filling chain of the JUNO reactor neutrino experiment. Its purpose is to validate the radiopurity of the scintillator to assure that all components of the JUNO scintillator system work to specifications and only neutrino-grade scintillator is filled into the JUNO Central Detector. The aspired sensitivity level of $$10^{-16}\hbox { g/g}$$ 10 - 16 g/g of $$^{238}\hbox {U}$$ 238 U and $$^{232}\hbox {Th}$$ 232 Th requires a large ($$\sim 20\,\hbox {m}^3$$ ∼ 20 m 3 ) detection volume and ultralow background levels. The present paper reports on the design and major components of the OSIRIS detector, the detector simulation as well as the measuring strategies foreseen and the sensitivity levels to U/Th that can be reached in this setup.
Cerebrospinal fluid (CSF) provides an invaluable analytical window to the central nervous system (CNS) because it reflects the dynamically changing complement of CNS constituents. We describe an improved method for sampling CSF in rats that is easy to perform. It has a 96% success rate of CSF collection and consistently yields large volumes (150–200 μl) of CSF. The blood contamination rate is also low (6%) as determined by both visual inspection and the lack of molecular detection of apolipoprotein B, a plasma-derived protein, which is absent in the CNS. This improved method of CSF sampling can have broad applicability in physiological and pharmacological evaluation for diverse CNS targets. We used this technique to provide proof of principle by examining the effect of intraperitoneal insulin on the level of apolipoprotein E (apoE) in the CSF. Insulin (0.5 and 1 U/kg) led to a significant increase of insulin in both plasma and CSF at 2 h after intraperitoneal administration and decreased blood glucose for at least 2 h. ApoE concentrations in CSF, but not in plasma, were also significantly increased, and its time-course was inversely correlated with the alterations in blood glucose over 2 h. These results provide a pharmacological validation of the novel CSF sampling and validation procedure for sampling rat CSF.
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