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Acoustic manipulation of porous spherical shells, widely used as drug delivery carriers and magnetic resonance imaging contrast agents, is investigated analytically. The technique used for this purpose is based on the application of high-order Bessel beams as a single-beam acoustic manipulation device, by which particles lying on the axis of the beam can be pulled toward the beam source. The exerted acoustic radiation force is calculated using the standard partial-wave series method, and the wave propagation within the porous media is modeled using Biot's theory of poro-elasticity. Numerical simulations are performed for porous aluminum and silica shells of different thickness and porosity. Results indicate that manipulation of low-porosity shells is possible using Bessel beams with large conical angles, over a number of broadband frequency ranges, whereas manipulation of highly porous shells can occur over both narrowband and broadband frequency domains.  相似文献   
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Metabolic Brain Disease - mTOR has been shown to be involved in the regulation of immune responses and differentiation of immune cells. This protein is a candidate molecule for unraveling the...  相似文献   
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Background:

Infection with Trichostrongylus spp. is common among human and herbivorous in most parts of Iran, especially in southern and northern areas. The aim of present study was to identify Trichostrongylus spp. among human population using excreted egg specimens, by the molecular method, in Mazandaran Province, northern Iran.

Methods:

Overall, 33 positive fecal specimens were randomly sampled and examined. PCR amplification of ITS2-rDNA region was performed on the isolated egg and then a restriction fragment length polymorphism (RFLP) profile was considered to discriminate of Trichostrongylus spp.

Results:

A total of 33 positive fecal specimens, 29(78.9%), 4(12.1%) were found T. colubriformis and T. axei respectively. Our data appear the molecular evidence of both human T. colubriformis and T. axei infections in North of Iran.

Conclusion:

T. colubriformis was the probable most common zoonotic species causing human trichostrongylosis infection in the area  相似文献   
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Background:

In leishmaniasis, some drugs prescribed for treatment have toxic effects and there are reports about drug resistance in some countries. Due to this fact, using herbal drugs such as artemisinin with good efficacy and low toxic effect might be suitable.

Methods:

We evaluated the apoptotic effect of artemisinin on Leishmania major in vitro and the antileishmanial activities of artemisinin on leishmaniasis in BALB/c mice and at the end INF-γ and IL-4 cytokines levels were detected by ELISA in spleen cell culture supernatants. During treatment the lesion size and survival rate were measured each four and ten days, respectively.

Results:

Percentage of early and late apoptosis in promastigotes of control group and promastigotes treated with 10, 25, 50 and 100 μg/ml of artemisinin after 48 h were 0.13, 16.04, 41.23, 49.03 and 81.83, respectively. The IFN-γ in ointment treated group were higher than those of other groups (P<0.05). The in vivo results showed that ointment compounds healed the lesions more effectively rather than intraperitoneal injection method (P<0.05). The survival rate of mice 150 days after challenge in treated group with ointment of artemisinin was 66% while all mice in control groups were died.

Conclusion:

All of in vitro results represented that this drug had antileishmanial effects and these results were confirmed by evaluation effects in vivo condition of leishmaniasis. Interestingly, according to these results it can be concluded that this drug has antileishmanial effects in vitro and in vivo conditions. Artemisinin induces cytotoxic effect on L. major via apoptosis-related mechanism.  相似文献   
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Sport Sciences for Health - The purpose of this study is to investigate the Bottom–Up Rise Strength Transfer (BURST) induced by massed vs. distributed-rehabilitative exercise training....  相似文献   
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Vascular endothelial growth factor (VEGF) plays a crucial role in angiogenesis within solid cancers. Thus, targeting VEGF might be part of a feasible therapy for treating pathological neovascularization, and nanobodies ? derived from heavy chain‐only antibodies occurring within Camelidae ? are a novel class of nanometer‐sized antibodies possessing unique properties that could be developed into a promising therapeutic. However, nanobodies have a very short half‐life in vivo due to their small size. Development of a bivalent nanobody is one way to remediate the half‐life problem of nanobodies. Two identical anti‐VEGF nanobodies were connected using the hinge region of llama IgG2c. The recombinant plasmid (pHEN6c‐bivalent nanobody) was transformed into E.coli WK6 cells and expression of the bivalent nanobody construct was induced with 1mM Isopropyl β‐D‐1‐thiogalactopyranoside (IPTG). Recombinant bivalent nanobody was purified using nickel affinity chromatography and its activity on human endothelial cells was assessed using 3‐(4,5‐Dimethylthiazol‐2‐yr)‐2,5‐diphenyltetrazolium bromide (MTT), tube formation, and cell migration assays. The pharmacokinetic study was performed after intravenous (i.v.) injection of recombinant bivalent nanobody into six‐week‐old C57BL/6 mice. Recombinant bivalent nanobody performed significantly better than monovalent nanobody in inhibiting proliferation, tube formation, and migration of human endothelial cells. Pharmacokinetic results showed a 1.8‐fold longer half‐life of bivalent nanobody in comparison with the monovalent nanobody. These results underscore the potential of recombinant anti‐VEGF bivalent nanobody as a promising tool for development of a novel therapeutic with an extended plasma half‐life for VEGF‐related diseases.  相似文献   
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