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1.
The variation of the essential‐oil composition among ten wild populations of Stachys lavandulifolia Vahl (Lamiaceae), collected from different geographical regions of Iran, was assessed by GC‐FID and GC/MS analyses, and their intraspecific chemical variability was determined. Altogether, 49 compounds were identified in the oils, and a relatively high variation in their contents was found. The major compounds of the essential oils were myrcene (0.0–26.2%), limonene (0.0–24.5%), germacrene D (4.2–19.3%), bicyclogermacrene (1.6–18.0%), δ‐cadinene (6.5–16.0%), pulegone (0.0–15.1%), (Z)‐hex‐3‐enyl tiglate (0.0–15.1%), (E)‐caryophyllene (0.0–12.9), α‐zingiberene (0.2–12.2%), and spathulenol (1.6–11.1%). For the determination of the chemotypes and the chemical variability, the essential‐oil components were subjected to cluster analysis (CA). The five different chemotypes characterized were Chemotype I (germacrene D/bicyclogermacrene), Chemotype II (germacrene D/spathulenol), Chemotype III (limonene/δ‐cadinene), Chemotype IV (pulegone), and Chemotype V (α‐zingiberene). The high chemical variation among the populations according to their geographical and bioclimatic distribution imposes that conservation strategies of populations should be made appropriately, taking into account these factors. The in situ and ex situ conservation strategies should concern all populations representing the different chemotypes.  相似文献   
2.
Psychopathic offenders show a persistent pattern of emotional unresponsivity to the often horrendous crimes they perpetrate. Recent studies have related psychopathy to alterations in white matter. Therefore, diffusion tensor imaging followed by tract-based spatial statistics (TBSS) analysis in 11 psychopathic offenders matched to 11 healthy controls was completed. Fractional anisotropy was calculated within each voxel and comparisons were made between groups using a permutation test. Any clusters of white matter voxels different between groups were submitted to probabilistic tractography. Significant differences in fractional anisotropy were found between psychopathic offenders and healthy controls in three main white matter clusters. These three clusters represented two major networks: an amygdalo-prefrontal network, and a striato-thalamo-frontal network. The interpersonal/affective component of the PCL-R correlated with white matter deficits in the orbitofrontal cortex and frontal pole whereas the antisocial component correlated with deficits in the striato-thalamo-frontal network. In addition to replicating earlier work concerning disruption of an amygdala-prefrontal network, we show for the first time that white matter integrity in a striato-thalamo-frontal network is disrupted in psychopathic offenders. The novelty of our findings lies in the two dissociable white matter networks that map directly onto the two major factors of psychopathy.  相似文献   
3.
Acute renal failure (ARF) is a clinical challenge that is highly resistant to treatment, and its high rate of mortality is alarming. Ischemia–reperfusion injury (IRI) is the most common cause of ARF. Especially IRI is implicated in kidney transplantation and can determine graft survival. Although the exact pathophysiology of renal IRI is unknown, the role of inflammatory responses has been elucidated. Because mesenchymal stromal cells (MSCs) have strong immunomodulatory properties, they are under extensive investigation as a therapeutic modality for renal IRI. Extracellular vesicles (EVs) play an integral role in cell-to-cell communication. Because the regenerative potential of the MSCs can be recapitulated by their EVs, the therapeutic appeal of MSC-derived EVs has dramatically increased in the past decade. Higher safety profile and ease of preservation without losing function are other advantages of EVs compared with their producing cells. In the current review, the preliminary results and potential of MSC-derived EVs to alleviate kidney IRI are summarized. We might be heading toward a cell-free approach to treat renal IRI.  相似文献   
4.
The Silent Information Regulator (SIR2) family of genes have been cloned from a variety of species ranging from bacteria to man. In previous studies, we reported the characterization of a Leishmania major gene encoding a protein with extensive homology to yeast SIR2p and expressed by different Leishmania species and parasite developmental stages and thus termed LmSIR2. Unlike the yeast SIR2p, LmSIR2p is mainly localized within the cytoplasm. In the present study, sequencing of a homologue encoding gene in another Leishmania species, Leishmania infantum, revealed 93% overall amino acid identity with L. major SIR2 gene. Further, using L. infantum as a recipient for a plasmid vector (pTEX) which allows overexpression of LmSIR2p led to the accumulation of the protein in the parasite cytoplasm of both promastigote and amastigote forms and a striking increase in the survival of amastigotes, the vertebrate stage of the parasite, when maintained under normal axenic culture conditions. This phenotype was also observed when L. infantum parasites were transfected with a cosmid vector (CLHyg), isolated from a L. infantum cosmid library, carrying the L. infantum SIR2 gene (CLHyg-LiSIR2). In contrast, no effect was observed on survival of the promastigote forms (insect stage) under similar culture conditions. However, when the glucose was used as a unique source of energy under starvation conditions, the viability of promastigotes was significantly enhanced. Moreover, we showed that amastigote forms in the stationary phase of culture died with a feature of apoptosis as revealed by the appearance of YOPRO-1 positive cells and that expression of LmSIR2 protein substantially delays this phenomenon. Taken together, these results demonstrate the existence of SIR2-related proteins encoding genes in different Leishmania species and suggest that LmSIR2p could participate among other factors in the control of cell death.  相似文献   
5.
Cartilage has a limited capacity for self-repair and focal damage can eventually lead to complete degradation of the tissue. Early diagnosis of degenerative changes in cartilage is therefore essential. Contrast agent-based computed tomography and magnetic resonance imaging provide promising tools for this purpose. However, the common assumption in clinical applications that contrast agents reach steady-state distributions within the tissue has been of questionable validity. Characterization of nonequilibrium diffusion of contrast agents rather than their equilibrium distributions may therefore be more effective for image-based cartilage assessment. Transport of contrast agent through the extracellular matrix of cartilage can be affected by tissue compression due to matrix structural and compositional changes including reduced pore size and fluid content. We therefore investigate the effects of static compression on diffusion of three common contrast agents: sodium iodide, sodium diatrizoate, and gadolinium diethylenetriamine-pentaacid (Gd-DTPA). Results showed that static compression was associated with significant decreases in diffusivities for sodium iodide and Gd-DTPA, with similar (but not significant) trends for sodium diatrizoate. Molecular mass of contrast agents affected diffusivities as the smallest one tested, sodium iodide, showed higher diffusivity than sodium diatrizoate and Gd-DTPA. Compression-associated cartilage matrix alterations such as glycosaminoglycan and fluid contents were found to correspond with variations in contrast agent diffusivities. Although decreased diffusivity was significantly correlated with increasing glycosaminoglycan content for sodium iodide and Gd-DTPA only, diffusivity significantly increased for all contrast agents by increasing fluid fraction. Because compounds based on iodine and gadolinium are commonly used for computed tomography and magnetic resonance imaging, present findings can be valuable for more accurate image-based assessment of variations in cartilage composition associated with focal injuries.  相似文献   
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7.
The role of novel triazine derivatives against oxidative stress exerted by hydrogen peroxide on differentiated rat pheochromocytoma (PC12) cell line was examined and a consistent protection from H2O2-induced cell death, associated with a marked reduction in caspase-3 activation, was observed. Moreover, activation of NF-κB, a known regulator of a host of genes that involves in specific stress and inflammatory responses by H2O2, was greatly impaired by triazine pretreatment in differentiated PC12 cells. Neuroprotective effect of such compounds may represent a promising approach for treatment of neurodegenerative diseases.  相似文献   
8.
Many rodent species act as reservoir hosts of zoonotic cutaneous leishmaniasis in endemic areas. In the present study a simple and reliable assay based on nested PCR was developed for the detection and identification of Leishmania parasites from rodent skin samples. We designed Leishmania-specific primers that successfully amplified ITS regions of Leishmania major, Leishmania gerbilli and Leishmania turanica using nested PCR. Out of 95 field collected Rhombomys opimus, 21 were positive by microscopic examination and 48 by nested PCR. The percentage of gerbils infected with L. major, L. gerbilli and L. turanica was 3.2%, 1.1% and 27.4%, respectively. In 15.8% of the rodents, we found mixed natural infections by L. major and L. turanica, 1.1% by L. major and L. gerbilli, and 2.1% by the three species. We concluded that this method is simple and reliable for detecting and identifying Leishmania species circulating in rodent populations.  相似文献   
9.
To identify a simple indicator for detection of follicular vitellogenesis stage of cultured Caspian brown trout, the changes of plasma calcium and estradiol-17β along with ovarian histology were investigated over a reproductive cycle. For this purpose, the blood and gonad samples were taken monthly over a six months period. According to results, the concentrations of plasma calcium increased significantly during October and November but then declined steadily until the end of experiment. Estradiol-17β concentrations were low throughout the experiment, a clear peak was observed in October. Histological observations showed that all examined females were in vitellogenesis when the peak of plasma calcium and estradiol-17β were observed. Also, significant positive relationship was found between plasma calcium and estradiol. The good fitness of plasma calcium and estradiol-17β peak with histological observations suggests that plasma calcium could be a good and simple indicator for detection of follicular vitellogenesis stage in the cultured Caspian brown trout.  相似文献   
10.
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