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61.
62.
Despite the effectiveness of renin-angiotensin blockade in retarding diabetic nephropathy progression, a considerable number of patients still develop end-stage renal disease. The present investigation aims to evaluate the protective potential of FPS-ZM1, a selective inhibitor of receptor for advanced glycation end products (RAGE), alone and in combination with valsartan, an angiotensin receptor blocker, against glomerular injury parameters in streptozotocin-induced diabetic rats. FPS-ZM1 at 1 mg/kg (i.p.), valsartan at 100 mg/kg (p.o.), and their combination were administered for 4 weeks, starting 2 months after diabetes induction in rats. Tests for kidney function, glomerular filtration barrier, and podocyte slit diaphragm integrities were performed. Combined FPS-ZM1/valsartan attenuated diabetes-induced elevations in renal levels of RAGE and phosphorylated NF-κB p65 subunit. It ameliorated glomerular injury due to diabetes by increasing glomerular nephrin and synaptopodin expressions, mitigating renal integrin-linked kinase (ILK) levels, and lowering urinary albumin, collagen type IV, and podocin excretions. FPS-ZM1 also improved renal function as demonstrated by decreasing levels of serum cystatin C. Additionally, the combination also alleviated indices of renal inflammation as revealed by decreased renal monocyte chemoattractant protein 1 (MCP-1) and chemokine (C-X-C motif) ligand 12 (CXCL12) expressions, F4/80-positive macrophages, glomerular TUNEL-positive cells, and urinary alpha-1-acid glycoprotein (AGP) levels. These findings underline the benefits of FPS-ZM1 added to valsartan in alleviating renal glomerular injury evoked by diabetes in streptozotocin rats and suggest FPS-ZM1 as a new potential adjunct to the conventional renin-angiotensin blockade.  相似文献   
63.
Deficiency in the PTS2 protein import pathway due to mutations in PEX7 gene results in the rhizomelic chondrodysplasia punctata (RCDP) type 1. In the present study, we have reported a novel missense mutation, W75R, in the PEX7 gene in an Iranian patient with the RCDP type 1. The inability of PEX7 protein to transport PTS2 containing proteins including peroxisomal 3-ketoacyl-CoA thiolase and PTS2-EGFP protein to the surface of the peroxisomes showed that the W75R mutation in PEX7 gene severely impaired the function of PEX7 protein and was responsible for RCDP type 1 in this patient.  相似文献   
64.

Folate deficiency is a public health concern affecting all age groups worldwide. The available evidence reveals that adding probiotic bacteria to the yoghurt starter cultures during yoghurt production process under fermentation conditions increases the folate content of yoghurt. The present study was conducted to measure two folate derivatives, i.e., 5-methyltetrahydrofolate and 5-formyltetrahydrofolate, in bio-fortified yoghurt samples including (1) yoghurt containing Streptococcus thermophilus and Lactobacillus bulgaricus, (2) probiotic yoghurt containing Lactobacillus acidophilus LA-5 and Bifidobacterium lactis BB-12, (3) probiotic yoghurt containing native strains of Lactobacillus plantarum 15HN, (4) probiotic yoghurt containing native strains of Lactococcus lactis 44Lac, and (5) probiotic yoghurt containing commercial strains of Lactobacillus plantarum LAT BY PL. During storage at 4 °C for 21 days, the highest levels of 5-methyltetrahydrofolate and 5-formyltetrahydrofolate, which were statistically significant, were detected in the yoghurt made using Lact. plantarum 15HN. Moreover, the highest total folate concentration (1487 ± 96.42 μg/L) was specified in the yoghurt containing Lact. plantarum 15HN on the 7th day. It can be conjectured that this product can be suggested as a proper alternative to synthetic folic acid and may not have the side effects of using synthetic folic acid overdoses.

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65.
Inflorescence and floral organogenesis and development of the bushy perennial legume Astragalus lagopoides of the section Hymenostegis were studied by means of epi-illumination light microscopy. Based on our observations, the primordia of lanceolate racemose inflorescences are born in the axils of leaves. Each inflorescence apex initiates acropetally bracts and floral apices for some time and then eventually ceases meristematic activity and forms an oblong-shaped terminal structure. The formation of such atypical terminal protrusion on the inflorescence meristem is judged to be a diagnostic feature for well-organized cessation of meristem morphogenesis. Pentamerous perfect flowers of the plant show strong zygomorphy and marked overlap in time of initiation among different organ primordia. Unexpectedly, sepal initiation is bidirectional starting from the lateral sides of the floral apex. Other significant developmental feature includes the existence of two types of common primordia, which are formed successively. From the primary common primordia there are produced antesepalous stamens and secondary common primordia. In comparison, the five secondary common primordia subdivide into a petal and an antepetalous stamen primordia. Initiation of two different types of common primordia is possibly the result of rising overlap in time of initiation of organs and demonstrates an advanced developmental style in the genus Astragalus.  相似文献   
66.
A new species of the genus Boleodorus, recovered from southern Iran, is described and illustrated based upon morphological and molecular data. B. bushehrensis n. sp. is mainly characterized by having a wide and low cephalic region (which is continuous with the adjacent body), the oral aperture in a depression in side view under a light microscope, four lines in the lateral field, weak metacorpus with a vestigial-to-invisible valve, and short (26–38 mm long) hooked tail with rounded tip. The females are 334–464 mm long and have a spherical spermatheca filled with spheroid sperm; males have 11.5- to 12.0-mm-long spicules and weakly developed bursa. The new species has an annulated low cephalic region, four large cephalic papillae, and small crescent-shaped amphidial openings when observed by scanning electron microscopy (SEM). Its morphological and morphometric differences with seven known species are discussed. The phylogenetic relationships of the new species with other relevant genera and species have been studied using partial sequences of small and large subunit ribosomal DNA (SSU and LSU rDNA). In both the SSU and LSU phylogenies, the sequences of B. bushehrensis n. sp. and other Boleodorus spp. formed a clade. A second species, B. thylactus, when studied under SEM, has a raised, smooth cephalic region, four large cephalic papillae, and oblique amphidial slits, with the oral opening in a depression.  相似文献   
67.
A series of 6-bromoquinazoline derivatives ( 5a – j ) were synthesized. Cytotoxic effectiveness of compounds was done against two cancerous cell lines (MCF-7 and SW480) by standard MTT method. Fortunately, all of the compounds showed desirable activity in reducing the viability of the studied cancerous cell lines with IC50 value in the range of 0.53–46.6 μM. Compound 5b with a fluoro substitution at meta position of the phenyl moiety showed stronger activity than cisplatin with IC50=0.53–1.95 μM. Studies on the hit compound ( 5b ) through apoptosis assay illustrated that it could induce apoptosis in MCF-7 cell lines in dose dependent manner. Molecular docking study was done to investigate the detailed binding modes and interactions with EGFR as a plausible mechanism. The drug- likeness was predicted. To survey the reactivity of compounds, DFT calculation was performed. Taken together, 6-bromoquinazoline derivatives, especially 5b can be considered as hit compounds to rational drug designing as antiproliferative agents.  相似文献   
68.
The systematics and phylogeny of the genus Arenaria and allied genera are unresolved. The use of morphological data has resulted in contradictory taxonomic concepts in the past due to their homoplastic nature. We present a phylogenetic analysis based on internal transcribed spacer (ITS) and rps16 sequence data of 140 (132 taxa) and 131 (120 taxa) accessions, respectively. Maximum parsimony and Bayesian analyses of each marker produced nearly congruent trees. Monophyly of Arenaria s.s. and Eremogone is confirmed here. Our results corroborate earlier results indicating that Arenaria subgenus Odontostemma is monophyletic, but outside the core group of Arenaria. Arenaria subgenus Solitaria is sister to Odontostemma and also not closely related to the latter; both of these subgenera are excluded from Arenaria and treated as distinct genera. The molecular data indicate that the ‘Arenaria s.s. clade’ consists of a few well‐supported subgroups and that the current subgeneric classification of the genus does not reflect evolutionary history. Arenaria subgenus Leiosperma is clearly monophyletic, but we reduce it to sectional level. Our molecular data show that the monotypic Arenaria subgenera Porphyrantha and Arenariastrum are nested in A. subgenus Arenaria, whereas subgenus Eremogoneastrum is included in Eremogone. None of the species‐rich sections in subgenus Arenaria is monophyletic. © 2015 The Linnean Society of London, Botanical Journal of the Linnean Society, 2015, 178 , 648–669.  相似文献   
69.
Adhesion of bacteria to clay minerals is of great importance in both natural soil environments and technological applications. In the present study, equilibrium experiments along with Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), and energy-dispersive X-ray analysis (EDX) were used to investigate the adhesion of Pseudomonas putida to the palygorskite and sepiolite clay minerals. The results showed that bacterial adhesion was rapid and reached equilibrium within 30 min. Equilibrium data showed that sepiolite has higher capacity and affinity than palygorskite for P. putida retention. Mixed FT-IR peak features of the clay minerals and P. putida were observed in the clay–bacteria complex spectra, indicating significant adhesion of P. putida to the minerals. However, some differences in the position of the individual bands were observed between infrared spectra obtained for pure bacteria or clay minerals and their corresponding clay–bacteria complexes, which are believed to be related to clay–bacteria interactions via different mechanisms. SEM/EDX analysis demonstrated fine fibrous clay particles adhered to the surface of individual P. putida cells. The results revealed rapid and close interactions of palygorskite and sepiolite with P. putida cells, which is important for better understanding the fate of bacteria in soil systems dominated by fibrous clay minerals and their practical applications in bioengineering and biotechnology.  相似文献   
70.
In this study, a novel method to probe molecular interactions and binding of human hemoglobin (Hb) with nanodiamond (ND) was introduced based on the surface tension measurement. This method complements conventional techniques, which are basically done by zeta potential and dynamic light scattering (DLS) measurements, near and far circular dichroism (CD) spectroscopy, intrinsic and extrinsic fluorescence spectroscopy. Addition of ND to Hb solution increased the surface tension value of Hb–ND complex relative to those of Hb and ND molecules. The zeta potential values reveled that Hb and ND provide identical charge distribution at pH 7.5. DLS measurements demonstrated that Hb, ND, and ND–Hb complex have hydrodynamic radiuses of 98.37 ± 4.57, 122.07 ± 7.88 nm and 62.27 ± 3.70 at pH of 7.5 respectively. Far and near UV-CD results indicated the loss of α-helix structure and conformational changes of Hb, respectively. Intrinsic fluorescence data demonstrated that the fluorescence quenching of Hb by ND was the result of the static quenching. The hydrophobic interaction plays a pivotal role in the interaction of ND with Hb. Fluorescence intensity changes over time revealed conformational change of Hb continues after the mixing of the components (Hb–ND) till 15 min, which is indicative of the denaturation of the Hb relative to the protein control. Extrinsic fluorescence data showed a considerable enhancement of the ANS fluorescence intensity of Hb–ND system relative to the Hb till 60 nM of ND, likely persuaded by greater exposure of nonpolar residues of Hb hydrophobic pocket. The remarkable decrease in Tm value of Hb in Hb–ND complex exhibits interaction of Hb with ND conducts to conformational changes of Hb. This study offers consequential discrimination into the interaction of ND with proteins, which may be of significance for further appeal of these nanoparticles in biotechnology prosecution.  相似文献   
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