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β‐Aminoisobutyric acid (BAIBA) is a catabolite of thymine and antiretroviral thymine analogues AZT and d4T. We recently discovered that this β‐amino acid is able to enhance fatty acid oxidation and reduce body weight in mice through an increased production of leptin by the white adipose tissue (WAT). Furthermore, BAIBA could have favourable effects on nonalcoholic steatohepatitis in a leptin‐independent manner. In the present review, we shall recall the circumstances that led us to discover the effects of BAIBA on body fat mass and lipid homeostasis. In addition, we put forward several hypothetical mechanisms whereby BAIBA could enhance leptin secretion by WAT and present some anti‐inflammatory effects in the liver. We also discuss in this review (i) the deleterious impacts caused by the absence of, or low leptin expression on lipid homeostasis and body weight in humans and animals and (ii) recent data from other investigators suggesting that increasing leptin levels and/or responsiveness may be indeed an attractive pharmacological strategy in order to prevent (and/or treat) obesity, at least in some individuals.  相似文献   
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Human exposure to Ochratoxin A (OTA) has been investigated in many Mediterranean countries, where OTA was found with a higher frequency in foodstuffs and blood samples. The aim of this study was to assess OTA concentrations in human blood serum in Tunisia and to evaluate the impact of several factors (age, origin, sex) on these prevalence reference values. One hundred and seven blood serum samples from healthy subjects were analyzed using a solid-phase extraction linked to a high-performance liquid chromatography (HPLC) method. OTA values ranged from 0 to 3.43 ng/mL with a mean value of 0.49±0.67 ng/mL. OTA levels were higher in the Sahal group. Our results reflect OTA concentration previously detected for human blood in Tunisia. Origin, but not age and sex, may affect the OTA reference values.  相似文献   
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Increasing evidences implicate impairment of axonal integrity in mechanisms underlying neurodegenerative disorders. Beta-boswellic acid (BBA) is the major component of Boswellia serrata gum. This resin has long been used in Ayurveda (India’s traditional medicine) to prevent amnesia. In this study, the effect of BBA was examined on neurites outgrowth and branching as well as on polymerization dynamics of tubulin. The morphometric parameters (axonal length and neuritis branching) were examined microscopically after treating the hippocampal cells with BBA. Also the assembly process of tubulin was assessed using UV/V is spectrophotometer through following of absorbance at 350 nm. The results revealed that BBA could significantly enhance neurite outgrowth, branching, and tubulin polymerization dynamics. The obtained results suggest that enhancing effect of BBA on microtubule polymerization kinetics might be the origin of increasing axonal outgrowth and branching.  相似文献   
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OBJECTIVE: Several studies have shown that lympho vascular space involvement (LVSI) and lymph node micrometastases (LNmM) may be risk factors for recurrence in early-stage cervical cancer with no apparent lymph node metastases. We performed a retrospective case-control study to reassess whether the presence of lymph node micrometastases and LVSI is predictive of subsequent recurrence following surgical resection of early-stage cervical cancer. METHODS: In a series of 292 patients diagnosed with early cervical cancer and treated by the same surgical procedure (laparoscopic-vaginal radical hysterectomy) during the same time period, two paired series were selected. The first series consisted of 26 cases who recurred in a median time of 36.8 months and the second series were 26 cases matched for age, histological sub-type, surgico-pathological stage and maximal tumor diameter, who did not recur after a median follow-up of 122 months. Sections taken from the hysterectomy specimens were reassessed for LVSI. All the lymph node blocks which have initially been considered as uninvolved were submitted to serial sectioning. Immunohistochemical staining using anti-cytokeratins AE1 and AE3 was used for identifying LNmM. RESULTS: LVSI was twice more frequent and LNmM ten-fold more frequent in the group of patients who recurred: 20/26 (77%) versus 9/26 (35%) and 11/26 (42%) versus 1/26 (4%) respectively. The relative risk of recurrence is 2.64 (1.67-5.49, P < 0.01) in the presence of LVSI and 2.44 (1.58-3.78, P < 0.01) in the presence of LNmM. All the patients with LNmM were LVSI positive. At bivariate analysis, the true LNmM (deposits more than 200 um in size) was the only independent risk factor. CONCLUSIONS: LNmM is an important risk factor of tumor recurrence in patients with early cervical cancer with no apparent lymph node metastases. LNmM seems to occur only in LVSI positive tumors. These data may lead to improve management of early-stage cervical cancer to reduce the risk of recurrence in those cases.  相似文献   
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Primary leiomyosarcoma of broad ligament   总被引:1,自引:0,他引:1  
BACKGROUND: Primary broad ligament leiomyosarcoma (LMS) is an extremely rare tumor with few well-documented cases. We are aware of 15 previously reported observations. AIM: Report of a new case. CASE: In this report we report a case of a right pelvic sidewall leiomyosarcoma with involvement of the appendix in a 49-year-old woman. A hysterectomy, bilateral salpingo-oophorectomy, omentectomy and appendicectomy were done, without complications. The patient died five months later. The case illustrates the difficulty of correct diagnosis before intervention. On this occasion, review of the literature confirms that this site remains unusual and the management is difficult.  相似文献   
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