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1.
BackgroundPortal vein embolization before liver resection is considered the therapy of choice for patients with inadequate future liver remnants. The concept of radioembolization with Yttrium-90 to achieve the same goal has limited data.MethodsWe retrospectively compared patients who underwent portal vein embolization and Yttrium-90 lobectomy before resection of hepatocellular carcinoma in patients with chronic liver disease.ResultsSeventy-three patients underwent portal vein embolization and 22 patients underwent Yttrium-90. Forty-seven percent of patients before portal vein embolization required additional procedures for tumor control, and 27% of patients after Yttrium-90 required additional procedure to mainly induce further hypertrophy. Both therapies achieved the goal of future liver remnants >40%, but the degree of hypertrophy was significantly higher in Yttrium-90 patients (63% for Yttrium-90, 36% for portal vein embolization, P < .01). Tumor response was significantly better with Yttrium-90, achieving complete response in 50% of patients. Resectability rate was higher after portal vein embolization (85% for portal vein embolization, 64% for Yttrium-90, P = .03). Tumor progression was the most common reason precluding surgery. Complete tumor control was the reason not to pursue surgery in 18% of patients after Yttrium-90.ConclusionBoth preoperative portal vein embolization and Yttrium-90, increases liver resectability rates by inducing hypertrophy of future liver remnants in patients with hepatocellular carcinoma and chronic liver disease. Yttrium-90 lobectomy achieved better tumor control and provided more time to assess therapy response, optimizing the indication for surgery.  相似文献   
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1,2-Dimethylhydrazine (DMH) is a toxic environmental pollutant which was reported also to be a colon-specific carcinogen. This study was performed to study the effect of bis-1,7-(2-hydroxyphenyl)-hepta-1,6-diene-3,5-dione, a bisdemethoxycurcumin analog (BDMC-A) on DMH-induced colon carcinogenesis in male Wistar rats and effects were compared with that of the reference drug, curcumin. Rats were given a weekly subcutaneous injection of DMH (20mg/kg body weight) in the groin, for 15 weeks. After a total experimental period of 32 weeks (including 2 weeks of acclimatization) tumor incidence was 100% in DMH-treated rats. Tumor was identified histologically as adenocarcinoma. Dysplasia, papillary pattern, cellular pleomorphism and carcinomatous glands were also noticed in DMH-treated rats. However, there was no colonic tumor in DMH+BDMC-A- and DMH+curcumin-treated rats but, lymphocyte infiltrations were observed. The levels of total bile acids and cholesterol in 24h fecal samples were significantly lower in DMH administered rats when compared to control rats, while, the excretion of bile acids and cholesterol were significantly increased and was near normal levels in DMH+BDMC-A- and DMH+curcumin-treated rats. In DMH-induced tumor bearing rats the levels of colonic and intestinal cholesterol was significantly increased whereas, the levels of phospholipid was decreased with a concomitant increase in the activities of phospholipase A (PLA) and phospholipase C (PLC), compared to untreated control rats. Intragastric administration of BDMC-A and curcumin to DMH administered rats significantly lowered the cholesterol content and raised the phospholipid content and lowered the activities of PLA and PLC towards near normal values. Our study shows that the protective effect of BDMC-A during DMH-induced colon carcinogenesis may be due to its modulatory effects on (i). histological changes, (ii). bile acids, (iii). cholesterol, and (iv). phospholipid metabolism in the target organ. Absence of histological changes in the colon of rats treated with BDMC-A, shows that long term administration of BDMC-A is nontoxic to experimental animals. Our study suggest that BDMC-A may emerge as a potent anticarcinogenic agent against colon cancer. As both BDMC-A and curcumin are equipotent in inhibiting the DMH-induced colon tumor incidence and normalizing histological changes, it could be concluded that the terminal phenolic group and the conjugated double bonds in the central seven carbon change may be responsible for the beneficial effects.  相似文献   
3.
Long‐term success of heart transplantation is hindered by humoral and cell‐mediated immune responses. We studied preexisting antibodies to cardiac self‐antigens, myosin and vimentin, and exosomes induced by antibodies to self‐antigens in eliciting immune responses to cardiac grafts. After syngeneic heterotopic murine heart transplantation, rabbit anti‐myosin or normal rabbit immunoglobulin was administered at day 0 or 7. Sera were collected after heartbeat cessation, cellular infiltration was analyzed, and exosomes were isolated from sera. Histopathologic examination of the controls' transplanted hearts demonstrated normal architecture, and their sera demonstrated neither antibodies to self‐antigens nor exosomes expressing self‐antigens. Administration of antibodies to cardiac myosin immediately posttransplantation (day 0) but not on day 7 triggered graft failure on day 7, and histopathologic examination revealed marked cellular infiltration with neutrophils and lymphocytes. Histopathologic examination of rejected hearts also demonstrated myocyte damage as sera had increased antibodies to myosin and vimentin and development of exosomes expressing self‐antigens. Administration of exosomes isolated from failed grafts containing self‐antigens induced graft dysfunction; exosomes isolated from stable mice did not induce graft failure. Antibodies to self‐antigens can induce exosomes containing self‐antigens, initiating an immune response and causing graft failure after cardiac transplantation.  相似文献   
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International Ophthalmology - To evaluate the frequency and outcomes of acute-onset endophthalmitis following combined pars plana vitrectomy and scleral fixation of intraocular lens. We evaluated...  相似文献   
6.
The nervous tissue of many vertebrates, including humans, can synthesize beta-alanyl-L-histidine (carnosine). The biological functions of carnosine are still open to question, although several theories supported by strong experimental data have been proposed. The objective of this study was to examine the effects of carnosine on neurotoxicity in differentiated rat pheochromocytoma (PC12) cells. Neurotoxicity was induced by N-methyl-D-aspartate (NMDA), which caused time- and concentration-dependent cell death as measured by MTT and LDH assays. Pretreatment with carnosine significantly prevented the neurotoxicity in a concentration-dependent manner. The protective effect of carnosine was antagonized by the H1 receptor antagonist pyrilamine, but not by the H2 receptor antagonist cimetidine. In addition, alpha-fluoromethylhistidine, a histidine decarboxylase inhibitor, slightly reversed the protective action of carnosine. These results indicate that carnosine can effectively protect against NMDA-induced necrosis in PC12 cells, and its protection may in part be due to the activation of the postsynaptic histamine H1 receptor. The study suggests that carnosine may be an endogenous protective factor and calls for its further study as a new anti-excitotoxic agent.  相似文献   
7.
Preplaced Aggregate Fibrous Concrete (PAFC) is a newly minted composite that has recently become more popular. The production of PAFC involves two essential processes; first, the fibres and coarse aggregate were filled into the empty framework to form the first layer of a natural skeleton, followed by grout injecting. A cement grout fills the voids in the first layer skeleton with slight compaction. This process is repeated to complete the remaining layers; hence, a type of Functionally-graded Preplaced Aggregate Fibrous Concrete (FPAFC) is obtained. The most recent studies revealed that the literature regarding the high-velocity projectile impact on fibrous concrete is well documented; however, the low-velocity repeated projectile impact on PAFC is still unexplored and needs particular emphasis. This research aims to investigate the FPAFC made with a new type of steel and polypropylene fibres against low-velocity projectile impact to fill this research gap. In the current study, twelve mixes were prepared with mono and hybrid combinations of fibres for pioneering the possible utilization of fibres in FPAFC. The maximum fibre dosage in this study is limited to 2.4%. The projectile impact resistance of FPAFC was assessed in line with penetration depth, front and rear damage surface area, weight loss, damage ratio and failure pattern. Additionally, a simplified analytical model was introduced to compute the ejected composite mass from the tested specimens. The results revealed that the addition of steel fibre in a single layer FPAFC exhibited an increasing compressive strength trend compared to the two/three-layered FPAFC. Furthermore, increasing the dosage of fibre at the bottom and top layers of FPAFC with a hybrid combination alleviates the spalling with an increasing number of impacts. The results from this research offer the reference information for more detailed research and studies of FPAFC under low-velocity projectile impact.  相似文献   
8.
Odor learning induces structural and functional modifications throughout the olfactory system, but it is currently unknown whether this plasticity extends to the olfactory receptors (Or) in the sensory periphery. Here, we demonstrate that odor learning induces plasticity in olfactory receptor expression in the honeybee, Apis mellifera. Using quantitative RT‐PCR analysis, we show that six putative floral scent receptors were differentially expressed in the bee antennae depending on the scent environment that the bees experienced. Or151, which we characterized using an in vitro cell expression system as a broadly tuned receptor binding floral odorants such as linalool, and Or11, the specific receptor for the queen pheromone 9‐oxo‐decenoic acid, were significantly down‐regulated after honeybees were conditioned with the respective odorants in an olfactory learning paradigm. Electroantennogram recordings showed that the neural response of the antenna was similarly reduced after odor learning. Long‐term odor memory was essential for inducing these changes, suggesting that the molecular mechanisms involved in olfactory memory also regulate olfactory receptor expression. Our study demonstrates for the first time that olfactory receptor expression is experience‐dependent and modulated by scent conditioning, providing novel insight into how molecular regulation at the periphery contributes to plasticity in the olfactory system.  相似文献   
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Extracts and preparations made from the animal origin were used extensively in folk and modern medicine for treating many human diseases. In the present study efforts have been made to find the antimicrobial effect of the mucus of two bottom dwelling fresh water fishes namely, Channa punctatus and Cirrhinus mrigala. Fish mucus were tested against ten pathogenic bacteria such as Escherichia coli, Klebsiella oxytoca, Klebsiella pneumoniae, Lactobacillus vulgaris, Proteus mirabilis, Pseudomonas aeruginosa, Salmonella paratyphi, Salmonella typhi, Staphylococcus aureus and Vibrio cholera. The activity was measured in terms of zone of inhibition in mm. The mucus collected from Cirrhinus mrigala shows a strong inhibiting activity than the mucus of Channa punctatus.  相似文献   
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