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1.
Calorie restriction (CR) is the most efficacious treatment to delay the onset of age-related changes such as mitochondrial dysfunction. However, the sensitivity of mitochondrial markers to CR and the age-related boundaries of CR efficacy are not fully elucidated. We used liver samples from ad libitum-fed (AL) rats divided in: 18-month-old (AL-18), 28-month-old (AL-28), and 32-month-old (AL-32) groups, and from CR-treated (CR) 28-month-old (CR-28) and 32-month-old (CR-32) counterparts to assay the effect of CR on several mitochondrial markers. The age-related decreases in citrate synthase activity, in TFAM, MFN2, and DRP1 protein amounts and in the mtDNA content in the AL-28 group were prevented in CR-28 counterparts. Accordingly, CR reduced oxidative mtDNA damage assessed through the incidence of oxidized purines at specific mtDNA regions in CR-28 animals. These findings support the anti-aging effect of CR up to 28 months. Conversely, the protein amounts of LonP1, Cyt c, OGG1, and APE1 and the 4.8 Kb mtDNA deletion content were not affected in CR-28 rats. The absence of significant differences between the AL-32 values and the CR-32 counterparts suggests an age-related boundary of CR efficacy at this age. However, this only partially curtails the CR benefits in counteracting the generalized aging decline and the related mitochondrial involvement.  相似文献   
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OBJECTIVE: Our objective was to determine the interest of laparoscopic assisted vaginal hysterectomy. STUDY DESIGN: Between January 1991 to december 1994, 80 patients had laparoscopically assisted vaginal hysterectomy. We reviewed with particular emphasis characteristic indications, complications. RESULTS: Eighty were performed as laparoscopically assisted vaginal hysterectomy. 14 patients (17.5%) had laparotomy conversion; because of size of uterus in 3 cases, suspected ovarian tumor in 3 cases. Pelvic adherences in 4 cases, urinary tract injuries in 1 case, hypercapnia in 1 case, hemorrhage in 2 cases. 9 patients experienced febrile morbidity and 1 urinary infection. 1 patient received 2 units of packed red blood cells. The hospital stay was 5 days for laparoscopically assisted vaginal hysterectomy versus 5.9 for laparotomic hysterectomy. CONCLUSION: Laparoscopically assisted vaginal hysterectomy offers a technique to convert certain abdominal hysterectomies into vaginal hysterectomies with a 17.5% laparoconversion rate.  相似文献   
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The light chain of tetanus neurotoxin (TeTx) is a zinc endopeptidase specific for VAMP/synaptobrevin (VAMP), a 120-amino-acid integral protein previously described in the small synaptic vesicles of neuronal cells. TeTx has been shown to be active also on nonneuronal cells. By SDS-PAGE and quantitative immunoblotting on proteins derived from murine macrophages (Mphi) exposed to TeTx, we have shown that: (1) VAMP-related proteins are also present in Mphi and (2) such proteins are sensitive to TeTx proteolytic cleavage. The demonstration that TeTx acts on VAMP-related proteins also in Mphi offers a new and useful tool for molecular studies on Mphi exocytosis.  相似文献   
4.
Functional alterations in irritable bowel syndrome have been associated with defects in bioenergetics and the mitochondrial network. Effects of high fat, adequate-protein, low carbohydrate ketogenic diet (KD) involve oxidative stress, inflammation, mitochondrial function, and biogenesis. The aim was to evaluate the KD efficacy in reducing the effects of stress on gut mitochondria. Newborn Wistar rats were exposed to maternal deprivation to induce IBS in adulthood. Intestinal inflammation (COX-2 and TRL-4); cellular redox status (SOD 1, SOD 2, PrxIII, mtDNA oxidatively modified purines); mitochondrial biogenesis (PPAR-γ, PGC-1α, COX-4, mtDNA content); and autophagy (Beclin-1, LC3 II) were evaluated in the colon of exposed rats fed with KD (IBD-KD) or standard diet (IBS-Std), and in unexposed controls (Ctrl). IBS-Std rats showed dysfunctional mitochondrial biogenesis (PPAR-γ, PGC-1α, COX-4, and mtDNA contents lower than in Ctrl) associated with inflammation and increased oxidative stress (higher levels of COX-2 and TLR-4, SOD 1, SOD 2, PrxIII, and oxidatively modified purines than in Ctrl). Loss of autophagy efficacy appeared from reduced levels of Beclin-1 and LC3 II. Feeding of animals with KD elicited compensatory mechanisms able to reduce inflammation, oxidative stress, restore mitochondrial function, and baseline autophagy, possibly via the upregulation of the PPAR-γ/PGC-1α axis.  相似文献   
5.
The ectopic pregnancy (EP) could be treated by spontaneous resolution, or medical treatment or laparoscopic treatment. Spontaneous resolution of EP with beta hCG < 1,000 mUl/ml, plasmatic progesterone < 5 ng/ml had 74% success rate. Methotrexate (MTX) injection is the common Medical treatment of EP with beta hCG < or = 5,000 mUl/ml and mean diameter of EP < or = 3 cm: a single dose of 50 mg/m2 or 1 mg/kg intramuscular injection had 93.4% success rate; local injection under sonographic control (1 mg/kg) had 80.2% success rate. The surgical conservative treatment by laparoscopy had 94% success rate.  相似文献   
6.
A complexity-bounded motion estimation algorithm   总被引:5,自引:0,他引:5  
The full search motion estimation algorithm for video coding is a procedure of high computational cost. For this reason, in real-time low-power applications, low-cost motion estimation algorithms are viable solutions. A novel reduced complexity motion estimation algorithm is presented. It conjugates the reduction of computational load with good encoding efficiency. It exploits the past history of the motion field to predict the current motion field. A successive refinement phase gives the final motion field. This approach leads to a sensible reduction in the number of motion vector that have to be tested. The complexity is lower than any other algorithm algorithms known to the authors, in the literature, it is constant as there is no recursivity in the algorithm and independent of any search window area size. Experimental evaluations have shown the robustness of the algorithm when applied on a wide set of video sequences-a good performance compared to other reduced complexity algorithms and negligible loss of efficiency versus the full search algorithm.  相似文献   
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The paper investigates efficient bandwidth allocation schemes for the transmission of MPEG-2 video traffic on high-speed networks. To this end we performed an extensive analysis of the traffic generated by an MPEG-2 encoder. Specifically, we encoded “The Sheltering Sky” movie according to the MPEG-2 standard. By the analysis of the generated traffic it results that a constant-quality transmission can be performed with a poor bandwidth utilization. In the paper we identified that the low bandwidth utilization is caused by rare high-rate periods in the codec bitstream. Hence, we identified the source scalability as a promising approach to achieve a “quasi-constant” quality transmission and an efficient bandwidth utilization. The effectiveness of this approach is evaluated in the paper via simulation. Specifically, by defining a Markovian model for an MPEG-2 scalable source we performed a set of simulation experiments which indicate that the source scalability approach significantly increases the utilization, while maintaining the quality of the video signal at the highest value for most of the time, e.g., a 50% of the network utilization with the highest quality for the 99.7% of the time.  相似文献   
10.
Glasses of composition Na2O·2SiO2 containing iron oxide are obtained by the gel technique. The results show that the iron atoms accelerate the formation of the glass, whereas when they are present in low percentage (∼2%), the temperature necessary to obtain the glass phase is higher. During heat treatment at 250°C, two silicates are formed: Na2SiO3 and Na4SiO4. When the iron content is low, they change at 650°C into Na2Si2O5, but when the iron content is higher (∼6%), this silicate does not form and the system becomes vitreous.  相似文献   
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