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21.

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   
22.

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   
23.
24.
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   
25.
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   
26.
Toll-like receptors (TLRs) are a major class of innate immune pattern recognition receptors that have a key role in immune homeostasis and the defense against infections. The research explosion that followed the discovery of TLRs more than a decade ago has boosted fundamental knowledge on the function of the immune system and the resistance against disease, providing a rational for clinical modulation of the immune response. In addition, the conserved nature of the ancient TLR system throughout the animal kingdom has enabled a comparative biology approach to understand the evolution, structural architecture, and function of TLRs. In the present review we focus on TLR biology in the avian species, and, especially, on the unique functional properties of the chicken TLR repertoire.  相似文献   
27.
Nanobodies for the first time were identified in the sera of Camelidae. Single-domain antibodies or nanobodies are a class of next-generation antibodies that have specific features: small size (in nanoscale), high penetration in various tissues, high stability in hard situations and ease production process in microbial systems. In fact single-domain antibodies are the smallest fragment of the antibody with binding ability. Unique characteristics and features of nanobodies make them an appropriate candidate for further evaluation as the development of novel antibody-based therapeutics. In this regard single-domain antibodies are in the interest of many researchers as well as biopharmaceutical companies for diagnostic and therapeutic applications. Nowadays several single domain antibodies have been developed and evaluated in different clinical trials. Because of many advantages of single-domain antibodies over other formats of antibodies, they could be good replacement for other formats of antibodies in near future. Here, we review the biology, engineering platforms and application of nanobodies.  相似文献   
28.
Increasing data have accumulated on the role of Cardiac Computed Tomography (CCT) in infective endocarditis (IE) with high accuracy for large vegetations, perivalvular complications and for exclusion of coronary artery disease to avoid invasive angiography. CCT can further help to clarify the etiology of infective prosthetic valve dysfunction (e.g. malposition, abscess, leak, vegetation or mass). Structural interventions have increased the relevance of CCT in valvular heart disease and have amplified its use. CCT may be ideally integrated into a multimodality approach that incorporates a central role of transesophageal echocardiography (TEE) with 18-FDG PET and/or cardiac magnetic resonance in individually selected cases, guided by the Heart Team. The coronavirus-19 (COVID-19) pandemic has resulted in renewed attention to CCT as a safe alternative or adjunct to TEE in selected patients. This review article provides a comprehensive, contemporary review on CCT in IE to include scan optimization, characteristics of common IE findings on CCT, published data on the diagnostic accuracy of CCT, multimodality imaging comparison, limitations and future technical advancements.  相似文献   
29.
As body size strongly determines the biology of an organism at all levels, it can be expected that miniaturization comes with substantial structural and functional constraints. Dwarf snakes of the genus Eirenis are derived from big, surface-dwelling ancestors, considered to be similar to those of the sister genus Dolichophis. To better understand the structural implications of miniaturization on the feeding apparatus in Eirenis, the morphology of the cranial musculoskeletal system of Dolichophis schmidti was compared with that of the miniature Eirenis punctatolineatus and E. persicus using high-resolution µCT data. The gape index was compared between D. schmidti and 14 Eirenis species. Our results show a relatively increased neurocranium size and decreased maximal jaw muscle force in E. persicus, compared with the D. schmidti, and an intermediate situation in E. punctatolineatus. A significant negative allometry in gape index relative to body size is observed across the transition from the Dolichophis to Pediophis and Eirenis subgenera. However, the gape index relative to head size showed a significant negative allometry only across the transition from the Dolichophis to Pseudocyclophis subgenus. In Dolichophis–Eirenis dwarfing lineages, different structural patterns are observed through miniaturization, indicating that overcoming the challenge of miniaturization has achieved via different adaptations.  相似文献   
30.

Purpose

The purpose of this study was to investigate the effect of repeated bouts of eccentric exercise on the nociceptive withdrawal reflex (NWR) threshold, a measure of sensitivity in the spinal nociceptive system.

Methods

Sixteen healthy students (age 25.7 ± 0.6 years, BMI 24.8 ± 1 kg m?2) participated in this randomized, controlled, crossover study. Two identical bouts of high-intensity eccentric exercises were performed on the tibialis anterior muscle 7 days apart. Control sessions involving no exercise were performed 4 weeks apart the exercise sessions. Pressure pain thresholds (PPT) and the NWR threshold were recorded before, immediately after, and 1 day after both bouts of exercise.

Results

Pressure pain thresholds decreased significantly at two of the muscle belly sites on the day after initial bout compared with baseline. NWR threshold decreased by 25 ± 4 % immediately after initial bout and by 30 ± 5 % the next day (p < 0.05) as an indication of generalized pain hypersensitivity. On the contrary, no changes were found in both pain thresholds after second bout of eccentric exercise indicating that both localized and generalized pain sensitivity were normalized.

Conclusion

In conclusion, this study for the first time documented that an initial bout of unaccustomed high-intensity eccentric exercise, which results in muscle soreness can induce central sensitization. A repeated bout of exercise, however, facilitates inherent protective spinal mechanisms against the development of muscle soreness.  相似文献   
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