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1.
This study used malondialdehyde (MDA) determination by HPLC and enzymatic assays for total serum peroxides and antioxidant capacity to evaluate oxidative stress in 47 healthy full-term small-for-gestational age (SGA) newborns vs 67 appropriate-for-gestational age (AGA) newborns. Blood samples were collected at delivery from umbilical cord artery and vein and from peripheral blood of the babies on the third day after birth. Blood samples of mothers were also collected and compared with blood of 29 normal non-pregnant women (NPW). Serum peroxide values were significantly higher in both groups of mothers than in NPW, decreasing towards the third day in AGA mothers, while persisting in SGA mothers. Antioxidant capacity of sera of both groups of mothers was lower than NPW. Both SGA mothers and babies had increased MDA at delivery, unlike AGA counterparts. MDA levels in umbilical vein were higher than in umbilical arteries, while immunohistochemistry revealed abundant presence of 4-hydroxynonenal (HNE)-protein adducts only in stroma of the SGA placenta. These results show that both mothers and babies are exposed to oxidative stress during and after delivery, which is more pronounced and persistent in the perinatal period of the SGA group, while lipid peroxidation in placenta could play a role in SGA pathophysiology.  相似文献   
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This report describes the synthesis, structure–activity relationships and activity of piperidine, homopiperidine, and azocane derivatives combining NK1 receptor (NK1R) antagonism and serotonin reuptake transporter (SERT) inhibition. Our studies culminated in the discovery of piperidine 2 and homopiperidine 8 as potent dual NK1R antagonists-SERT inhibitors. Compound 2 demonstrated significant activity in the gerbil forced swimming test, suggesting that dual NK1R antagonists-SERT inhibitors may be useful in treating depression disorders.  相似文献   
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We explored the interplay between the intracellular energy sensor AMP‐activated protein kinase (AMPK), extracellular signal‐regulated kinase (ERK), and autophagy in phorbol myristate acetate (PMA)‐induced neuronal differentiation of SH‐SY5Y human neuroblastoma cells. PMA‐triggered expression of neuronal markers (dopamine transporter, microtubule‐associated protein 2, β‐tubulin) was associated with an autophagic response, measured by the conversion of microtubule‐associated protein light chain 3 (LC3)‐I to autophagosome‐bound LC3‐II, increase in autophagic flux, and expression of autophagy‐related (Atg) proteins Atg7 and beclin‐1. This coincided with the transient activation of AMPK and sustained activation of ERK. Pharmacological inhibition or RNA interference‐mediated silencing of AMPK suppressed PMA‐induced expression of neuronal markers, as well as ERK activation and autophagy. A selective pharmacological blockade of ERK prevented PMA‐induced neuronal differentiation and autophagy induction without affecting AMPK phosphorylation. Conversely, the inhibition of autophagy downstream of AMPK/ERK, either by pharmacological agents or LC3 knockdown, promoted the expression of neuronal markers, thus indicating a role of autophagy in the suppression of PMA‐induced differentiation of SH‐SY5Y cells. Therefore, PMA‐induced neuronal differentiation of SH‐SY5Y cells depends on a complex interplay between AMPK, ERK, and autophagy, in which the stimulatory effects of AMPK/ERK signaling are counteracted by the coinciding autophagic response.

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The purpose of this study was to examine the effects of ghrelin on protein kinase B (Akt) and mitogen-activated protein kinase p42/44 (ERK1/2) activation as well as ghrelin effects on inducible nitric oxide (NO) synthase (iNOS; for gene Nos2) activity/expression in rat hearts. Male Wistar rats were treated with ghrelin (0.3 nmol/5 μl) or an equal volume of phosphate-buffered saline, injected every 24 h into the lateral cerebral ventricle for 5 days and 2 h after the last treatment the animals were sacrificed. Serum NO, L-arginine (L-Arg), and arginase activity were measured spectrophotometrically. For phosphorylation of Akt, ERK1/2, and iNOS protein expression, Western blot method was used. The expression of Nos2 mRNA was measured by the quantitative real-time polymerase chain reaction (qRT-PCR). Treatment with ghrelin significantly increased NO production in serum by 1.4-fold compared with control. The concentration of L-Arg was significantly higher in ghrelin-treated rats than in control while arginase activity was significantly lower in ghrelin-treated than in control hearts. Ghrelin treatment increased phosphorylation of Akt by 1.9-fold and ERK1/2 by 1.6-fold and increased iNOS expression by 2.5-fold compared with control. In addition, ghrelin treatment increased Nos2 gene expression by 2.2-fold as determined by qRT-PCR. These results indicate that ghrelin regulation of iNOS expression/activity is mediated via Akt/ERK1/2 signaling pathway. These results may be relevant to understanding molecular mechanisms underlying direct cardiovascular actions of ghrelin.  相似文献   
5.
Collagen metabolism is altered in the pelvic organ tissues of women with genital prolapse. The aim of this study was to compare collagen metabolism by measuring matrix metalloproteinase-1 (MMP-1) expression in uterosacral ligament tissues of postmenopausal women with and without genital prolapse. Uterosacral ligament tissues were obtained at the time of abdominal or vaginal surgery from twenty-four patients with pelvic organ prolapse (POP) and 21 women who underwent gynecologic surgery for benign indications. The tissue samples were analyzed by immunohistochemistry. There were no differences in age, BMI and parity between two groups. The patients with genital prolapse demonstrated significantly higher occurences of MMP-1 expression compared to controls. These findings indicate that increased MMP-1 expression in uterosacral ligaments is associated with genital prolapse. Our data are consistent with the theory that increased collagen breakdown may play an important role in the onset and development of pelvic organ prolapse (POP).  相似文献   
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Natural killer T (NKT) and regulatory T cells (Tregs) play an important role in innate immune response. Natural killer (NK) and NKT cells are indispensable factors in the body's ongoing defense against tumor development, as well as viral infection. NKT cells are a subset of T cells that shares properties of natural killer cells and conventional T cells. They are involved in innate immune responses, tumor rejection, post transplantation immunotherapy, immune surveillance and control of autoimmune diseases. They may also play both protective and harmful roles in the progression of certain autoimmune diseases, such as diabetes, lupus, atherosclerosis, and allergen-induced asthma. Immune surveillance involves the process whereby precancerous and malignant cells are recognized by the host immune system as damaged and are consequently targeted for elimination. The pharmacological management of postoperative pain in patients with malignancies uses very different techniques whose possible cytotoxic functions we still known very poor. The present study compared effects of two different postoperative pain management techniques in patients undergoing colorectal cancer surgery on the innate immunity. Our data indicate that the patients with colorectal cancer have significantly increased the percentage of Tregs and NKT cells. The values were statistically higher during epidural analgesia in comparison with intravenous analgesia, indicating that epidural pain management technique ameliorate the immune suppression after surgery.  相似文献   
9.
Epilepsy is one of the most common neurological problems affecting approximately 1% of the world's population with higher incidence among elderly individuals. Although depression is a common comorbid condition in patients with epilepsy, there is a paucity of information regarding depression in geriatric patients with epilepsy. This study analysed a group of 83 patients affected by different epilepsy phenotypes accompanied by mental disorders, especially depression. Antiepileptic and antipsychotic drug treatment has been evaluated, particularly a positive effect of the new antiepileptics (monotherapy and polytherapy) both on the reduction of seizures and mental disorders.  相似文献   
10.
20-hydroxyvitamin D(2) [20(OH)D(2)] inhibits DNA synthesis in epidermal keratinocytes, melanocytes, and melanoma cells in a dose- and time-dependent manner. This inhibition is dependent on cell type, with keratinocytes and melanoma cells being more sensitive than normal melanocytes. The antiproliferative activity of 20(OH)D(2) is similar to that of 1,25(OH)(2)D(3) and of newly synthesized 1,20(OH)(2)D(2) but significantly higher than that of 25(OH)D(3). 20(OH)D(2) also displays tumorostatic effects. In keratinocytes 20(OH)D(2) inhibits expression of cyclins and stimulates involucrin expression. It also stimulates CYP24 expression, however, to a significantly lower degree than that by 1,25(OH)(2)D(3) or 25(OH)D(3). 20(OH)D(2) is a poor substrate for CYP27B1 with overall catalytic efficiency being 24- and 41-fold lower than for 25(OH)D(3) with the mouse and human enzymes, respectively. No conversion of 20(OH)D(2) to 1,20(OH)(2)D(2) was detected in intact HaCaT keratinocytes. 20(OH)D(2) also demonstrates anti-leukemic activity but with lower potency than 1,25(OH)(2)D(3). The phenotypic effects of 20(OH)D(2) are mediated through interaction with the vitamin D receptor (VDR) as documented by attenuation of cell proliferation after silencing of VDR, by enhancement of the inhibitory effect through stable overexpression of VDR and by the demonstration that 20(OH)D(2) induces time-dependent translocation of VDR from the cytoplasm to the nucleus at a comparable rate to that for 1,25(OH)(2)D(3). In vivo tests show that while 1,25(OH)(2)D(3) at doses as low as 0.8 μg/kg induces calcium deposits in the kidney and heart, 20(OH)D(2) is devoid of such activity even at doses as high as 4 μg/kg. Silencing of CY27B1 in human keratinocytes showed that 20(OH)D(2) does not require its transformation to 1,20(OH)(2)D(2) for its biological activity. Thus 20(OH)D(2) shows cell-type dependent antiproliferative and prodifferentiation activities through activation of VDR, while having no detectable toxic calcemic activity, and is a poor substrate for CYP27B1.  相似文献   
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