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1.
Abstract: Light microscopic observations on the superficial pineal gland of Wistar-King rats were made to examine whether or not pineal volume and pinealocyte size, expressed as nuclear density, at daytime or nighttime are affected by long-term exposure to 50 Hz rotating magnetic field (MF) at 5.0 μT. Determinations of pineal volume and pinealocyte size were repeated twice (April and October) during the year. Size of pinealocytes in MF-exposed and sham-exposed rats exhibited, in addition to the difference between peripheral and central regions, regional differences in a proximodistal direction; pinealocytes in the distal and middle-peripheral regions were usually larger than those in the proximal and middle-central regions at daytime or nighttime. In October, distal and proximal pinealocytes showed significant day-night changes in size in sham-exposed rats, but not in MF-exposed animals. The situations in the two groups were almost reversed in April. Significant day-night differences were scarcely found in pinealocyte size in the middle region in the two groups. Throughout the study, pineal volume and pinealocyte size in each region were generally the same between MF-exposed and sham-exposed rats at daytime or nighttime. The results suggest that pinealocytes in the distal and proximal regions, but not those in the middle region, are affected by MF-exposure; day-night differences in sizes of distal and proximal pinealocytes appear in April and disappear in October under the influence of MF. MF may exert an effect on mechanisms controlling day-night rhythms of pinealocyte size in the rat.  相似文献   
2.
Abstract: We report here two cases in a family with pleomorphic clinical features which include mitochondrial myopathy, encephalopathy, stroke-like episodes, episodic disturbances of consciousness and other multisystemic abnormalities. The other signs observed in multisystemic abnormalities were ophthalmoplegia, short stature, diabetes mellitus, diabetes insipidus, renal dysfunction, optic atrophy, retinal degeneration, impairment of hearing and mental retardation or deterioration. A symptomatological variation was observed in cases in the same family. It is suggested that these widely varying symptoms may be expressions caused by a common biochemical defect which involves different tissuesin different individuals in the family. The syndromes observed in the present cases were compared with other possibly-related mitochondrial encephalomyopathies.  相似文献   
3.
Secretogranin III (SgIII), a member of the granin protein family, is expressed specifically in neuronal and endocrine cells. To examine the precise localization of SgIII in the endocrine pancreas, pancreatic tissues of rats were analyzed immunocytochemically with a polyclonal anti-serum raised against rat SgIII. By light microscopy of semithin sections, the immunoreactivity for SgIII was readily detected in pancreatic A- and B-cells, faintly so in D-cells, and not at all in the exocrine pancreas. By immunoelectron microscopy, immunogold particles indicative of SgIII were observed in the peripheral regions of secretory granules, and universally in the pancreatic endocrine cells. Morphometrical analyses indicated that SgIII is most preferentially localized in the periphery of the secretory granule among granins. These findings suggest that SgIII is closely associated with the secretory granule membrane, serving to anchor the aggregates of other soluble constituents to the membrane.  相似文献   
4.
Functional and nutraceutical foods provide an alternative way to improve immune function to aid in the management of various diseases. Traditionally, many medicinal products have been derived from natural compounds with healing properties. With the development of research into nutraceuticals, it is becoming apparent that many of the beneficial properties of these compounds are at least partly due to the presence of polyphenols. There is evidence that dietary polyphenols can influence dendritic cells, have an immunomodulatory effect on macrophages, increase proliferation of B cells, T cells and suppress Type 1 T helper (Th1), Th2, Th17 and Th9 cells. Polyphenols reduce inflammation by suppressing the pro-inflammatory cytokines in inflammatory bowel disease by inducing Treg cells in the intestine, inhibition of tumor necrosis factor-alpha (TNF-α) and induction of apoptosis, decreasing DNA damage. Polyphenols have a potential role in prevention/treatment of auto-immune diseases like type 1 diabetes, rheumatoid arthritis and multiple sclerosis by regulating signaling pathways, suppressing inflammation and limiting demyelination. In addition, polyphenols cause immunomodulatory effects against allergic reaction and autoimmune disease by inhibition of autoimmune T cell proliferation and downregulation of pro-inflammatory cytokines (interleukin-6 (IL-6), IL-1, interferon-γ (IFN-γ)). Herein, we summarize the immunomodulatory effects of polyphenols and the underlying mechanisms involved in the stimulation of immune responses.  相似文献   
5.
6.
The patient with goiter and his or her physician frequently overlook symptoms of upper respiratory obstruction. Conventional radiology is the accepted method for detecting upper airway obstruction in these patients. Flow volume loops provide additional information on airflow dynamics. Twenty-five patients of goiter undergoing surgery were evaluated for upper airway obstruction by symptomatology, conventional radiology, and flow volume loops. Flow volume loops were repeated 1 month after surgery. Ten (40%) patients had mild symptoms on direct questioning. Tracheal deviation, compression, or both were noted in eight (32%) patients on radiology. Flow volume loops detected upper airway obstruction in 15 (60%) patients. Surgery resulted in normalization of all preoperative abnormal curves. The flow volume loop is a simple noninvasive method for detecting upper airway obstruction in patients with goiter. Abnormal upper airway dynamics are present in more patients with goiter than previously recognized, and relief of this obstruction should be an important aspect of thyroid surgery.  相似文献   
7.

Purpose

Sorafenib is primarily metabolized in the liver, by CYP3A4-mediated oxidation and UGT1A9-mediated glucuronidation. However, there is little information about the pharmacokinetic interaction of sorafenib. Here, we report a pharmacokinetic interaction between sorafenib and the CYP3A4 inducer prednisolone in a patient with hepatocellular carcinoma (HCC).

Patients and methods

The patient was a 72-year-old woman diagnosed with HCC. She was treated with sorafenib at 400 mg daily. On day 9, sorafenib was discontinued due to drug eruption. Nine months later, she was rechallenged with sorafenib at 400 mg daily concurrently with oral prednisolone. Prednisolone was started at 20 mg daily and was tapered by 5 mg every 14 days. We assessed the pharmacokinetics of sorafenib and its major metabolite M-2.

Results

The concentration of sorafenib was gradually increased following tapering of prednisolone. On day 56 after rechallenge, she developed G3 oral mucositis. At this time, serum trough concentrations of sorafenib and M-2 were at 5.9 and 1.1 μg/ml, respectively. Consequently, sorafenib dosage was reduced to 200 mg daily, and the oral mucositis was attenuated. The subsequent concentrations of sorafenib and M-2 obtained with a dose of 200 mg daily ranged from 1 to 3 μg/ml and from 0.1 to 0.4 μg/ml, respectively. Computed tomography scan showed a complete response of the liver tumor with no further recurrence of the rash.

Conclusions

We have demonstrated for the first time that prednisolone stimulates the sorafenib metabolism and that therapeutic drug monitoring could be useful during sorafenib therapy.  相似文献   
8.
This work was carried out to explore the compounds of bismuth with carbon using density functional theory (DFT)-based computations. The structures of the compounds BiC, BiC2, BiC3, Bi2C3, BiC5, and Bi2C5 were predicted at a generalized gradient approximation (GGA-PBE) level of theory. The calculations were carried out on the structures in unit cell and supercell geometries in slab and bulk periodicities. The structural and electronic properties of the mentioned compounds were investigated in detail. The calculations of the structures revealed lattice constants of the compounds for cubic unit cell as 212.2 pm for BiC, 176.9 pm for BiC2, 240.5 pm for BiC3, 232.4 pm for Bi2C3, and 354.5 pm for Bi2C5. The compounds BiC, BiC2, BiC3, BiC5, and Bi2C5 were found to be metallic, whereas Bi2C3 exhibited semiconducting character with a band gap of 0.305 eV. This work provides an initial framework for preparing new 2D materials from BixCy.  相似文献   
9.
Live‐cell imaging with fluorescent proteins (FPs) is a powerful tool for investigating the exocytosis processes of hormones. However, the secretion process of glucagon‐like peptide‐1 (GLP‐1) has not been visualized by FPs, which might be because tagging FPs inhibits GLP‐1 synthesis through the post‐translational processing from proglucagon. Here, we have developed FP‐tagged GLP‐1 by inserting FPs into the middle of GLP‐1 and adding the proglucagon signal peptide. Confocal imaging confirmed that GLP‐1 fused to FPs with high folding efficiency showed granular structure, in which secretory vesicle markers colocalized. The fluorescence intensity of FP in the culture supernatant from cells treated with KCl or forskolin was significantly increased compared with those from untreated cells. Furthermore, FP‐tagged GLP‐1 enables direct visualization of stimulation‐dependent exocytosis of GLP‐1 at a single granule resolution with total internal reflection fluorescence microscopy. FP‐tagged GLP‐1 might facilitate the screening of GLP‐1 secretagogues and the discovery of new antidiabetic drugs.  相似文献   
10.
Established guidelines discuss end-of-life care in patients with implantable cardioverter-defibrillators (ICDs). It is not known how frequently these discussions take place in patients who have ICDs and are receiving active treatment for cancer. Chart review from a large regional cardiac and cancer center from 2005 to 2019 highlighted that discussions on ICD deactivation were infrequent (28% of patients). Receipt of a palliative care consultation increased the likelihood of patients having discussions on ICD deactivation during this time. Collaboration with palliative care teams may facilitate discussions on ICD deactivation during this opportune time.  相似文献   
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