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Phyllodes tumors of the breast: the role of pathologic parameters   总被引:8,自引:0,他引:8  
We aimed to establish whether morphologic parameters were prognostically important in a large series of breast phyllodes tumors in Asian women. Of 335 phyllodes tumors diagnosed at the Department of Pathology, Singapore General Hospital, Singapore, between January 1992 and December 2002, 250 (74.6%) were benign, 54 (16.1%) borderline, and 31 (9.3%) malignant, based on histologic review of archival slides. Of the women, 43 (12.8%) experienced recurrences during the follow-up period. Recurrent disease was correlated with grade or classification (P = .028), stromal atypia (P = .016), stromal hypercellularity (P = .046), and permeative microscopic borders (P = .021). Multivariate analysis revealed that independent predictors of recurrence were pseudoangiomatous stromal hyperplasia (PASH) and margin status, whereby the presence of PASH and complete or negative margins reduced recurrence hazards by 51.3% and 51.7% respectively. The 7 women who died of disease during follow-up had malignant phyllodes tumor at the outset and experienced recurrences, and death was preceded by distant metastases.  相似文献   
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Purpose  Oxidative stress has been implicated in the etiology of defective embryo development. Vitamin E is an effective lipid-soluble antioxidant, protecting cell membranes from peroxidative damage. In this context, this study was undertaken to find if supplementation of vitamin E in culture medium could ameliorate the developmental competence of preimplantation buffalo embryos. Methods  Vitamin E was supplemented in maturation/embryo culture medium at concentrations of 0, 50, 100, 200 and 400 μM. The developmental competence of buffalo embryos was assessed by observing the cleavage, morulae, blastocyst rate, total cell count and comet assay. Results  Vitamin E had no significant effect in maturation medium. Vitamin E in embryo culture medium under 5% O2 significantly reduced blastocyst formation in the 400 μM supplemented group. Culture under 20% O2 enhanced the frequency of blastocyst formation, total cell count and significantly reduced comet tail in the 100 μM supplemented group (P < 0.001) when compared with the control. Vitamin E in ECM for the first 72 h of culture period enhanced blastocyst rate and total cell number in the 100 μM group (P < 0.001) when compared with the control. Conclusion  Our results demonstrate that the addition of Vitamin E may enhance the developmental competence of buffalo embryos in vitro by protecting them from oxidative stress. Capsule Buffalo embryos are prone to oxidative stress due to high lipid content; supplementation of vitaminE enhanced their developmental competence by protecting them from oxidative stress.  相似文献   
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For nearly a decade, silver nanoparticles (AgNPs) have been the most prevalent commercial nanomaterials products widely used in different biomedical applications due to their broad-spectrum antimicrobial activity. However, their poor long-term stability in different environments, namely, pH, ionic strength, and temperature, and cytotoxicity toward mammalian cells has restricted their more extensive applications. Hence, there is urgent need to develop highly biocompatible, non-toxic, and stable silver nanoparticles for wide-ranging environments and applications. In the present study, a simple, sustainable, cost-effective and green method has been developed to prepare highly stable aqueous colloidal silver nanoparticles (AgNPs-EW) using the ovalbumin, ovotransferrin, and ovomucoid of egg-white as reducing and capping agents accomplished under the irradiation of direct sunlight. Then, we evaluated the effects of freezing–drying (lyophilization) and freeze–thaw cycles on the stability of AgNPs-EW in aqueous solution under visual inspection, transmission electron microscopy, and absorbance spectroscopy. In addition, we studied the antibacterial activity against Salmonella typhimurium and Escherichia coli, carried out biocompatibility studies on chicken blood, and tested acute, chronic toxicity in Drosophila melanogaster. The results suggest that AgNPs-EW did not aggregate upon freeze-thawing and lyophilization, thus exhibiting remarkable stability. The antibacterial activity results showed that the AgNPs-EW had the highest antibacterial activity, and the minimum inhibitory concentration (MIC) of AgNPs-EW for E. Coli and S. typhimurium were 4 and 6 μg ml−1, respectively. The biocompatibility study revealed that the AgNPs-EW did not induce any hemolytic effect or structural damage to the cell membranes of chicken erythrocytes up to a concentration of 12 μg ml−1. Similarly, no acute and chronic toxicity was observed on melanization, fecundity, hatchability, viability, and the duration of development in the 1st generation of Drosophila melanogaster at the concentration range of 10 mg L−1 to 100 mg L−1 of AgNPs-EW, and all the flies completed their full developmental cycle. Therefore, the present study successfully demonstrated the green and sustainable preparation of non-toxic AgNPs-EW having good biocompatibility, enhanced colloidal stability, and antibacterial activity. Hence, the synthesized AgNPs-EW could be used for the development of an antimicrobial formulation for controlling microbial infection.

For nearly a decade, silver nanoparticles (AgNPs) have been the most prevalent commercial nanomaterials products widely used in different biomedical applications due to their broad-spectrum antimicrobial activity.  相似文献   
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Mosquitoes are insect vectors responsible for the transmission of parasitic and viral infections to millions of people worldwide, with substantial morbidity and mortality. Infections transmitted by mosquitoes include malaria, yellow fever, chikungunya, filariasis and other arboviruses. Insecticides of botanical origin may serve as suitable alternative biocontrol techniques in the future. The adulticidal activities of crude hexane, benzene, ethyl acetate, acetone and methanol leaf extracts of Acalypha alnifolia were assayed for their toxicity against three important vector mosquitoes, viz., Aedes aegypti, Anopheles stephensi and Culex quinquefasciatus. The adult mortality was observed after 24 h of exposure. All extracts showed moderate adulticide effects; however, the highest adult mortality was found in methanol extract were observed. The LC50 values of A. alnifolia leaf extracts against adulticidal activity of (hexane, benzene, ethyl acetate, acetone and methanol) A. aegypti, A. stephensi and C. quinquefasciatus were the following: A. aegypti values were 371.87, 342.97, 320.17, 300.86 and 279.75 ppm; A. stephensi values were 358.35, 336.64, 306.10, 293.01 and 274.76 ppm; C. quinquefasciatus values were 383.59, 354.13, 327.74, 314.33 and 291.71 ppm. The results of the repellent activity of hexane, benzene, ethyl acetate, acetone and methanol extract of A. alnifolia plant at three different concentrations of 1.0, 3.0, and 5.0 mg/cm2 were applied on skin of forearm in man and exposed against adult female mosquitoes. In this observation, this plant crude extracts gave protection against mosquito bites without any allergic reaction to the test person, and also, the repellent activity is dependent on the strength of the plant extracts. Mean percent hatchability of the ovicidal activity was observed 48 h post-treatment. The percent hatchability was inversely proportional to the concentration of extract and directly proportional to the eggs. Mortality of 100 % with methanol extract of A. alnifolia was exerted at 125 and 300 ppm. The larval density was decreased after the treatment of plant extracts at the breeding sites (water bodies system) of vector mosquitoes, and hence, these plant extracts are suitable alternatives of synthetic insecticides for mosquito vector management.These results suggest that the leaf solvent plant extracts have the potential to be used as an ideal eco-friendly approach for the control of mosquitoes. This study provides first report on the mosquito ovicidal, repellent and adulticidal activities of these plant extracts against mosquito vector species from India.  相似文献   
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An efficient and eco-friendly protocol for the synthesis of bioactive silver nanoparticles was developed using Naringi crenulata leaf extracts via microwave irradiation method. Silver nanoparticles were synthesized by treating N. crenulata leaf extracts with 1 mM of aqueous silver nitrate solution. An effective bioactive compound such as alkaloids, phenols, saponins and quinines present in the N. crenulata reduces the Ag+ into Ag0. The synthesized silver nanoparticles were monitored by UV–vis spectrophotometer and further characterized by X-ray diffraction (XRD), Fourier Transform Infra Red (FTIR), Energy-dispersive X-ray spectroscopy (EDX) and field emission scanning electron microscopy (FESEM). UV–vis spectroscopy showed maximum absorbance at 390 nm due to surface plasmon resonance of AgNPs. From FESEM results, an average crystal size of the synthesized nanoparticle was 72–98 nm. FT-IR results showed sharp absorption peaks and they were assigned to phosphine, alkyl halides and sulfonate groups. Silver nanoparticles synthesized were generally found to be spherical and cubic shape. Topical application of ointment prepared from silver nanoparticles of N. crenulata were formulated and evaluated in vivo using the excision wound healing model on Wistar albino rats. The measurement of the wound areas was performed on 3rd, 6th, 9th, 12th and 15th days and the percentage of wound closures was calculated accordingly. By the 15th day, the ointment base containing 5% (w/w) of silver nanoparticles showed 100% wound healing activity compared with that of the reference as well as control bases. The results strongly suggested that the batch C ointment containing silver nanaoparticles synthesized from the leaf extracts of N. crenulata was found to be very effective in wound repair and encourages harnessing the potentials of the plant biomolecules loaded silver nanoparticle in the treatment of tropical diseases including wound healing.  相似文献   
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OBJECT: The authors evaluated the neuroprotective effect of 5,10,15,20-tetrakis(N-methyl-4'-pyridyl)porphyrinato-iron(III) (FeTMPyP), a peroxynitrite decomposition catalyst, and 1,5-isoquinolinediol (ISO), a poly(adenosine diphosphate [ADP]-ribose) polymerase (PARP) inhibitor, alone and in combination in rats with focal cerebral ischemia induced by middle cerebral artery occlusion (MCAO). METHODS: Male Sprague-Dawley rats were subjected to 2 hours of MCAO followed by 22 hours of reperfusion. Cerebral infarction and neurological deficits were estimated after ischemia. Intraperitoneal injections of FeTMPyP (1 and 2 mg/kg) and ISO (0.05 and 0.1 mg/kg) were administered alone or in combination in ischemic animals. The PARP activity in vehicle- and drug-treated groups was estimated using anti-poly(ADP-ribose) antibody in immunofluorescence and immunoblotting studies. Two hours of MCAO and 22 hours of reperfusion produced significant cerebral infarction and neurological deficits. Treatment with FeTMPyP (1 and 2 mg/kg) and ISO (0.05 and 0.1 mg/kg) produced a significant reduction in cerebral infarction and neurological deficits. Combination therapy (2 mg/kg FeTMPyP and 0.1 mg/kg ISO) enhanced the inhibition of ischemic volume (77.81+/-0.86%) compared with monotherapies (FeTMPyP 54.07+/-5.6% and ISO 53.06+/-3.88%). Immunoblotting and immunofluorescence studies showed PARP activation after ischemia, which was reduced by drug treatment. CONCLUSIONS: Neuroprotection observed with FeTMPyP and ISO alone and in combination may be attributed to inhibition of the peroxynitrite-PARP cascade of cerebral ischemia/reperfusion injury.  相似文献   
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