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41.

Background

Allergic reactions have been implicated as contributions in a number of atopic disorders, including atopic dermatitis (AD), allergic rhinitis (AR) and bronchial asthma (BA). However, the potential for filaggrin protein, eosinophil major basic protein (MBP) and immunoglobulin E (IgE) to elicit allergic response or to contribute to atopic disorders remains largely unexplored in pediatric patients. This study was undertaken to investigate the status and contribution of filaggrin protein, eosinophil MBP and total IgE in pediatric patients with AD, AR and BA.

Methods

Sera from 395 pediatric patients of AD, AR or BA with varying levels of disease activity according to the disease activity index and 410 age-matched non-atopic healthy controls were evaluated for serum levels of atopic markers, including filaggrin, eosinophil MBP and IgE.

Results

Serum analysis showed that filaggrin levels were remarkably high in pediatric patients with AD, followed by BA and AR, whereas its levels were low in non-atopic pediatric controls. Eosinophil MBP levels in sera of atopic patients were significantly high as compared with their respective controls, but its levels were highest in AR patients, followed by AD and BA. Total IgE in sera of AD patients was markedly high, followed by AR and BA patients, whereas its levels were low in non-atopic pediatric controls. Interestingly, not only was an increased number of subjects positive for filaggrin protein, eosinophil MBP or total IgE, but also their levels were statistically significantly higher among those atopic patients whose disease activity scores were higher as compared with atopic patients with lower disease activity scores.

Conclusions

These findings strongly support a role of filaggrin protein, eosinophil MBP and IgE in the onset of allergic reactions in pediatric patients with AD, AR and BA. The data suggest that filaggrin, eosinophil MBP or IgE might be useful in evaluating the progression of AD, AR or BA and in elucidating the mechanisms involved in the pathogenesis of these pediatric disorders.
  相似文献   
42.
In recent years, fluorescence microscopy imaging has become an important tool for studying cell structure and function. This non invasive technique permits characterization, localisation and qualitative quantification of free ions, messengers, pH, voltage and a pleiad of other molecules constituting living cells. In this paper, we present results using various commercially available fluorescent probes as well as some developed in our laboratory and discuss the advantages and limitations of these probes in confocal microscopy studies of the cardiovascular system.  相似文献   
43.
Background and objective: The aim of the present study was to develop and examine a new non-invasive injectable graft for the repair of alveolar bone clefts using recombinant human bone morphogenetic protein-2 (rhBMP-2) encapsulated within injectable liposomal in situ gel (LIG).

Method: Different liposomal formulations loaded with rhBMP-2 were prepared, and the effects of the preparation methods and lipid content on the efficiency of rhBMP-2 encapsulation within the liposomes were studied. For the preparation of in situ gel, deacetylated gellan gum (DGG) was used, and the in vitro gelation characteristics of the gel were evaluated. In vivo pharmacokinetics and histology were also assessed. Critical size alveolar defects were surgically created in the maxillae of 30 New Zealand rabbits and treated with different injectable formulae, including rhBMP-2 liposomes and in situ gel (rhBMP-2-LIG).

Results: The results indicated that the prepared rhBMP-2-LIG prolonged the release and residence time of BMP-2 within rabbits for more than 7 days. Histomorphometric assessment showed 67% trabecular bone filling of the defects treated using this novel formula.

Conclusion: BMP-2-LIG is a promising delivery device for the repair of alveolar bone defects associated with cleft deformities.  相似文献   

44.
The aim of the study was to investigate the ameliorative effects of curcumin on fibrinogen like protein‐2 (fgl‐2), some oxido‐inflammatory and apoptotic markers in rat‐induced acute pancreatitis (AP). Seventy‐five albino rats were divided into control group, l ‐arginine (l ‐Arg)‐induced AP group, curcumin pre‐treated group before AP induction, curcumin post‐treated group after AP induction, and curcumin injected group only. AP group showed severe necrotizing pancreatitis confirmed by histopathological changes and elevations in serum amylase and lipase activities, levels of epithelial neutrophil‐activating peptide 78, tissue content of protein carbonyls, levels of tumor necrosis factor α, and caspase‐3 as well as myeloperoxidase activity. Significant elevation in pancreatic fgl‐2 mRNA expression was detected in AP group. Improvement of all parameters was detected with increase of caspase‐3 in both curcumin‐treated groups that confirmed curcumin ameliorative effects against AP through induction of apoptosis and inhibition of micro‐thrombosis, inflammation, and oxidative stress.  相似文献   
45.
OBJECTIVE: To compare Papanicolaou (Pap) and May-Grünwald Giemsa (MGG) stain as 2 techniques for staining for buccal mucosal cells to detect micronuclei (MN) infield studies. STUDY DESIGN: Eighty cytologic smears (2 per individual) were taken from the buccal mucosa of 40 cigarette smokers recruited at a rural village in Egypt. Forty smears were stained with Pap stain and 40 with MGG stain. All were assessed for cellularity and scored for MN. RESULTS: Pap stain was faster and easier to process and transport in the field study than was MGG stain. Regarding MGG smears, bacteria and cell debris masked the MN as compared to Pap smears, in which the fixative destroyed the bacteria and made the cell boundaries clearly demarcated. Using Pap stain, MN were seen easily in transparent cytoplasm. CONCLUSION: Pap stain is the preferred method infield studies for scoring and detecting MN in cells of buccal mucosa.  相似文献   
46.
Picosecond fluorescence kinetics of wild-type (WT) and mutant cells of Synechocystis sp. PCC 6803, were studied at the ensemble level with a streak-camera and at the cell level using fluorescence-lifetime-imaging microscopy (FLIM). The FLIM measurements are in good agreement with the ensemble measurements, but they (can) unveil variations between and within cells. The BE mutant cells, devoid of photosystem II (PSII) and of the light-harvesting phycobilisomes, allowed the study of photosystem I (PSI) in vivo for the first time, and the observed 6-ps equilibration process and 25-ps trapping process are the same as found previously for isolated PSI. No major differences are detected between different cells. The PAL mutant cells, devoid of phycobilisomes, show four lifetimes: ∼20 ps (PSI and PSII), ∼80 ps, ∼440 ps, and 2.8 ns (all due to PSII), but not all cells are identical and variations in the kinetics are traced back to differences in the PSI/PSII ratio. Finally, FLIM measurements on WT cells reveal that in some cells or parts of cells, phycobilisomes are disconnected from PSI/PSII. It is argued that the FLIM setup used can become instrumental in unraveling photosynthetic regulation mechanisms in the future.  相似文献   
47.
The mammalian target of rapamycin (mTOR) Ser/Thr kinase signals in at least two multiprotein complexes distinguished by their different partners and sensitivities to rapamycin. Acute rapamycin inhibits signaling by mTOR complex 1 (mTORC1) but not mTOR complex 2 (mTORC2), which both promote cell growth, proliferation, and survival. Although mTORC2 regulation remains poorly defined, diverse cellular mitogens activate mTORC1 signaling in a manner that requires sufficient levels of amino acids and cellular energy. Before the identification of distinct mTOR complexes, mTOR was reported to autophosphorylate on Ser-2481 in vivo in a rapamycin- and amino acid-insensitive manner. These results suggested that modulation of mTOR intrinsic catalytic activity does not universally underlie mTOR regulation. Here we re-examine the regulation of mTOR Ser-2481 autophosphorylation (Ser(P)-2481) in vivo by studying mTORC-specific Ser(P)-2481 in mTORC1 and mTORC2, with a primary focus on mTORC1. In contrast to previous work, we find that acute rapamycin and amino acid withdrawal markedly attenuate mTORC1-associated mTOR Ser(P)-2481 in cycling cells. Although insulin stimulates both mTORC1- and mTORC2-associated mTOR Ser(P)-2481 in a phosphatidylinositol 3-kinase-dependent manner, rapamycin acutely inhibits insulin-stimulated mTOR Ser(P)-2481 in mTORC1 but not mTORC2. By interrogating diverse mTORC1 regulatory input, we find that without exception mTORC1-activating signals promote, whereas mTORC1-inhibitory signals decrease mTORC1-associated mTOR Ser(P)-2481. These data suggest that mTORC1- and likely mTORC2-associated mTOR Ser-2481 autophosphorylation directly monitors intrinsic mTORC-specific catalytic activity and reveal that rapamycin inhibits mTORC1 signaling in vivo by reducing mTORC1 catalytic activity.  相似文献   
48.
Pesticides have been used to kill pests such as insects, fungi, rodents, and unwanted plants. As these compounds are potentially toxic to the target organisms, they could also be harmful to human health and the environment. Several chronic adverse effects have been identified even after months or years of exposure. The adverse effects of pesticides on the agricultural ecosystem have been a matter of concern in recent decades. In this review, we present an overview of the studies, including our previous studies, monitoring currently used pesticides in the Tunisian agricultural soils that belong to the class of insect growth regulators (IGRs). Triflumuron (TFM) is a benzoyl phenyl urea insecticide belonging to the class of IGRs. TFM is widely used around the world to increase crop yield by protecting them from damage caused by insects. TFM works by inhibiting the synthesis of chitin, an essential part of the insect cuticle, making it susceptible to pathogens and deformities. Consequently, insects become more susceptible to pathogens and malformations. However, studies revealing its toxicity and its mode of action in mammalian systems remain very limited. The aim of this review is to better inform the community about the impact of TFM on crops, the environment, and human beings by summarizing its toxic effects.  相似文献   
49.
Members of the double-stranded RNA-specific ribonuclease III (RNase III) family were shown to affect cell division and chromosome segregation, presumably through an RNA interference-dependent mechanism. Here, we show that in Saccharomyces cerevisiae, where the RNA interference machinery is not conserved, an orthologue of RNase III (Rnt1p) is required for progression of the cell cycle and nuclear division. The deletion of Rnt1p delayed cells in both G1 and G2/M phases of the cell cycle. Nuclear division and positioning at the bud neck were also impaired in Deltarnt1 cells. The cell cycle defects were restored by the expression of catalytically inactive Rnt1p, indicating that RNA cleavage is not essential for cell cycle progression. Rnt1p was found to exit from the nucleolus to the nucleoplasm in the G2/M phase, and perturbation of its localization pattern delayed the progression of cell division. A single mutation in the Rnt1p N-terminal domain prevented its accumulation in the nucleoplasm and slowed exit from mitosis without any detectable effects on RNA processing. Together, the data reveal a new role for a class II RNase III in the cell cycle and suggest that at least some members of the RNase III family possess catalysis-independent functions.  相似文献   
50.
Apolipoproteins (lipid-free) are lipid-binding proteins that circulate in the plasma of human blood and are responsible for the clearance of lipoproteins. Apolipoprotein E (ApoE) is one of the several classes of this protein family. It acts as a ligand for the low-density lipid (LDL) receptors and is important for the clearance of very low-density lipid (VLDL) and chylomicron remnants. The APOE gene locus is polymorphic, with three major known alleles, APOE*3, *4, and *2. We investigated the distribution of the allele frequency of the APOE gene locus and describe here the genetic variation in four Kuwaiti subpopulations: Arab origin (Arabian peninsula), Arab Bedouin tribes, Iranian origin, and the heterogeneous population. We also describe the use of Spreadex gels in resolving the amplified and digested products of the APOE gene locus. DNA was extracted from whole blood and subjected to PCR and then to RFLP analysis. Allele and genotype frequencies were estimated for the total population and for each subpopulation. Statistical analysis showed no difference in the allele frequencies between the four groups. The frequency of APOE*3 in the Kuwaiti population was highest (88.4%) followed by the frequency of APOE*4 (6.5%) and APOE*2 (5.1%). The genotype and allele frequencies obtained for the Kuwaiti population fell within the reported worldwide distribution for the APOE gene locus. Moreover, the results obtained in this study showed no statistical difference (p > 0.05) between the APOE allele and genotype frequencies between the subgroups for all six genotypes and three alleles, supporting the assumption of admixture in the Kuwaiti population and that the obtained frequencies were in Hardy-Weinberg equilibrium. Finally, we found that the distribution of the APOE alleles in Kuwait differs somewhat from those reported in other Arab populations, suggesting that the Arabs originating from the Arabian peninsula are different from those of Lebanon, Morocco, and Sudan.  相似文献   
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