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1.
The effect of 1α-hydroxyvitamin D3 (1α(OH)D3) on the metabolic bone disorders developed in gastrectomized rats were investigated biochemically and histomorphologically. 1α(OH)D3 was suspended in 0.2 % Triton-X-100 aqueous solution after dissolving in a very small amount of ethanol, was given orally to the rats for 10 weeks. The sham operated animals and the gastrectomy control animals received the vehicle alone. Gastrectomy was followed by the development of the metabolic bone disorders after 10 weeks of observation. This was characterized by reduction in ash content of the femur and histologically by a disappearance of the trabecular bone in tibial metaphysis. Decrease Ca absorption from the intestines was demonstrated by a radiotracer technique. Biochemical studies showed significant decreases in serum 25(OH)D concentration in gastrectomized rats. These findings suggest that gastrectomy partially impairs intestinal absorption of calcium and results in a negative calcium balance, which may contribute to the development of bone metabolic disorders in rats. The administration of 1α(OH)D3 increased dose-dependently serum calcium and Ca absorption from the intestine and prevented the development of bone metabolic disorders histomorphologically.  相似文献   
2.
Neutrophilia, defined as a large number of neutrophils in the circulating blood, is caused by increased differentiation and survival from activation-induced apoptosis. Regulation of apoptosis is essential for neutrophil homeostasis; however, the molecular signaling that regulates this process needs further investigation. Unlike TLR4 wild-type C3H/HeN mice, TLR4 mutated C3H/HeJ mice were insusceptible to LPS-induced blood neutrophilia. LPS prevented constitutive apoptosis in neutrophils and partly involved a blockade of the mitochondrial pathway including mitochondria transmembrane potential loss, myeloid cell leukemia sequence (Mcl) 1 degradation, and caspase-3 activation. In apoptotic neutrophils, glycogen synthase kinase (GSK)-3β was activated, and inhibiting GSK-3β decreased Mcl-1 degradation and apoptosis. LPS caused p38 MAPK-, JNK-, and PI3K/AKT-mediated Mcl-1 stabilization and prevented apoptosis, and LPS induced GSK-3β inactivation mainly through p38 MAPK and PI3K/AKT. Neutrophils in the neutrophilia showed increased GSK-3β inactivation and Mcl-1 stabilization accompanied by activation of p38 MAPK, JNK, and AKT. Notably, LPS-induced ROS generation can partly facilitate p38 MAPK/JNK/AKT activation to regulate GSK-3β-mediated Mcl-1 stability, apoptosis, and neutrophilia. These results demonstrate that the molecular basis of endotoxemic neutrophilia is through a direct action on neutrophils involving GSK-3β inactivation to prevent constitutive apoptosis.  相似文献   
3.
Malignant fibrous histiocytoma (MFH) of the breast is very rare. Sonographic findings of MFH of the breast have not been reported before. We herein report a case of a 46-year-old woman with a histologically proved MFH of her right breast. Ultrasound examination revealed a 6-cm tumor mass with solid and cystic components, which were attributed after histological examination to hypercellularity and hemorrhage within the tumor. Histopathological diagnosis was compatible with MFH of the breast.  相似文献   
4.
Understanding the neuroprotective effects of the rosemary phenolic diterpene carnosic acid (CA) has attracted increasing attention. We explored the mechanism by which CA modulates the neurotoxic effects of 6-hydroxydopamine (6-OHDA) in SH-SY5Y cells. Cells were pretreated with CA for 12 h followed by treatment with 100 μM 6-OHDA for 12 or 24 h. Cell viability determined by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolim bromide (MTT) assay indicated that 0.1 to 1 μM CA dose-dependently attenuated the cell death induced by 6-OHDA, whereas the effect of 3-5 μM CA was weaker. CA at 1 μM suppressed the 6-OHDA-induced nuclear condensation, reactive oxygen species generation, and cleavage of caspase 3 and PARP. Immunoblots showed that the phosphorylation of c-Jun NH(2)-terminal kinase (JNK) and p38 by 6-OHDA was reduced in the presence of CA. Incubation of cells with CA resulted in significant increases in the total glutathione (GSH) level and the protein expression of the γ-glutamylcysteine ligase catalytic subunit and modifier subunit. l-Buthionine-sulfoximine, an inhibitor of GSH synthesis, attenuated the effect of CA on cell death and apoptosis. Treatment with CA also led to an increase in nuclear factor erythroid-2 related factor 2 (Nrf2) activation, antioxidant response element (ARE)-luciferase reporter activity, and DNA binding to the ARE. Silencing of Nrf2 expression alleviated the reversal of p38 and JNK1/2 activation by CA. These results suggest that the attenuation of 6-OHDA-induced apoptosis by CA is associated with the Nrf2-driven synthesis of GSH, which in turn down-regulates the JNK and p38 signaling pathways. The CA compound may be a promising candidate for neuroprotection in Parkinson's disease.  相似文献   
5.
AIM: We studied the effect of colchicine combined with radiation on the survival of human hepatocellular carcinoma (HCC) HA22T/VGH cells. METHODS: Twenty-four hours after treatment with 0-8 ng/mL colchicine, HA22T/VGH cells were irradiated at various doses (0,1, 2, 4, and 8 Gy). Colony assay was performed to assess the surviving cell fraction. Survival curves were fitted by using a linear-quadratic model to estimate the sensitizer enhancement ratio (SER). Flow cytometry was used for cell cycle analysis. RESULTS: Colchicine at lower concentrations (1 and 2 ng/mL) had obvious synergy with radiation to inhibit HCC cell growth, whereas higher concentrations (4 and 8 ng/mL) had only additive effect to radiation. Pretreatment with 1 and 2 ng/mL colchicine for 24-h enhanced cell killing by radiation with SERs of 1.21 and 1.53, respectively. G2/M arrest was only observed with higher colchicine doses (8 and 16 ng/mL) after 24-h treatment; this effect was neither seen with lower doses (1, 2, and 4 ng/mL) nor with any dose after only 1 h of treatment. CONCLUSION: Our results suggest that colchicine has potential as an adjunct to radiotherapy for HCC treatment. Lower doses of colchicine possess radiosensitizing effects via some mechanism other than G2/M arrest. Further study is necessary to elucidate the mechanism.  相似文献   
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BACKGROUND: The fibrous mediopatellar plica can cause high contact pressure on the adjacent articular cartilage and lead to its degeneration. The purpose of this study was to investigate the biomechanical properties of the plica and to correlate this with the plica's fiber content and patients' ages. METHODS: An experimental study on the tensile strength of the mediopatellar plica was conducted using high precision micro-force tensile tests. These tests were undertaken on plica specimens taken from 50 knees of patients with different ages. The force-deflection curves resulting from these tests were recorded and transferred to stress-stain curves to obtain the Young's moduli of these specimens. In addition, pathological tissue dyeing tests were used to assess the fiber content ratio of each specimen. The relationship of the Young's moduli of these specimens with the severity of their pathologic change was also evaluated. FINDINGS: The Young's modulus of the plica was found to be ranging from 10 to 110 MPa. It has positive correlation with patient's age. The relationship between the fiber content ratio and Young's modulus can be fitted properly using a quadratic regression model. The Young's modulus of the plica was also positively correlated with the severity of its pathologic change. INTERPRETATION: The test results indicated that as patients get older, the fiber content of the mediopatellar plica and the Young's modulus of the plica will increase accordingly. We also demonstrated that the Young's modulus of the medial plica was positively correlated with the severity of the plica lesion.  相似文献   
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AIM: To analyze systematically our experience over 22 years with symptomatic acquired diverticular disease of the jejunum and ileum, exploring the clinical manifestations and diagnosis of this rare but life-threatening disease. METHODS: The medical records of patients with surgically confirmed symptomatic jejunoileal diverticular disease were retrospectively reviewed. Data collected included demographic data, laboratory results, clinical course (acute or chronic), preoperative diagnosis, and operative findings. Inclusion criteria were as follows: (1) surgical confirmation of jejunoileal diverticular disease and (2) exclusion of congenital diverticula (e.g. Meckel'sdiverticulum). RESULTS: From January 1982 to July 2004, 28 patients with a total of 29 operations met the study criteria. The male:female ratio was 14:14, and the mean age was 62.6卤3.5 years. The most common manifestation was abdominal pain. In nearly half of the patients, the symptoms were chronic. Two patients died after surgery. Only four cases were correctly diagnosed prior to surgery, three by small bowel series. CONCLUSION: Symptomatic acquired small bowel diverticular disease is difficult to diagnose. It should be considered in older patients with unexplained chronic abdominal symptoms. A small bowel series may be helpful in diagnosing this potentially life-threatening disease.  相似文献   
10.
Nicotine-containing electronic cigarette liquid (e-liquid) is prohibited in many countries, creating requirements for rapid detection approaches for on-site inspection or screening for large amounts of samples. Here, we demonstrate a simple way to identify nicotine using surface-enhanced Raman scattering (SERS) with substrates made of silver nanoparticle arrays imbedded in anodic aluminum oxide nanochannels (Ag/AAO). Compared with the reported colloidal nanoparticle-based SERS, that required serial dilutions to enable colloid aggregation in the viscous e-liquid, a small amount of undiluted e-liquid sample can be directly added onto our solid-phase Ag/AAO substrate without any pre-treatment. The sensitivity of our SERS measurements is 2–3 orders of magnitude higher than that required for identification of nicotine in e-liquid, which is typically around 1000–18,000 ppm. Using such nanoparticle array-based SERS, we have tested 22 commercially available e-liquid products, using the corresponding gas chromatography-mass spectrometry (GC–MS) reports as the reference. The SERS measurements were done within one hour and successfully identified 20 samples. Only 2 samples showed SERS interference from ingredients that were not suitable for SERS analysis.  相似文献   
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