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Examination of adult rat brain regions by specific radioimmunoassays revealed a widespread distribution of transforming growth factor-alpha (TGF-alpha), but not epidermal growth factor (EGF), the peptide that had previously been reported to be present in rodent brain. Polyadenylated RNA samples from the different regions of rat brain were analyzed by Northern blot to identify mRNA species encoding precursor proteins for EGF (preproEGF), TGF-alpha (preproTGF-alpha), and the EGF/TGF-alpha receptor. The results indicate that TGF-alpha is the most abundant ligand for the EGF/TGF-alpha receptor in most parts of the brain analyzed. Message for preproEGF was only detectable after prolonged autoradiographic exposure; levels of preproEGF mRNA were between two and three orders of magnitude lower in brain than those expressed in control tissue (kidney), and one to two orders of magnitude lower than preproTGF-alpha mRNA levels in all brain regions. These results were confirmed by analysis of mRNA by RT/PCR, and support the hypothesis that expression of preproEGF mRNA in the brain is limited to smaller discrete areas, whereas preproTGF-alpha gene expression is almost ubiquitous.  相似文献   
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Metabolomics offers a powerful means to investigate human malaria parasite biology and host-parasite interactions at the biochemical level, and to discover novel therapeutic targets and biomarkers of infection. Here, we used an approach based on liquid chromatography and mass spectrometry to perform an untargeted metabolomic analysis of metabolite extracts from Plasmodium falciparum-infected and uninfected patient plasma samples, and from an enriched population of in vitro cultured P. falciparum-infected and uninfected erythrocytes. Statistical modeling robustly segregated infected and uninfected samples based on metabolite species with significantly different abundances. Metabolites of the α-linolenic acid (ALA) pathway, known to exist in plants but not known to exist in P. falciparum until now, were enriched in infected plasma and erythrocyte samples. In vitro labeling with (13)C-ALA showed evidence of plant-like ALA pathway intermediates in P. falciparum. Ortholog searches using ALA pathway enzyme sequences from 8 available plant genomes identified several genes in the P. falciparum genome that were predicted to potentially encode the corresponding enzymes in the hitherto unannotated P. falciparum pathway. These data suggest that our approach can be used to discover novel facets of host/malaria parasite biology in a high-throughput manner.  相似文献   
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Purpose

In vitro anticancer effect and in vivo biodistribution and biocompatibility of metformin encapsulated O-Carboxymethyl chitosan nanoparticles were evaluated for its application as pancreatic cancer therapy.

Methods

In vitro studies such as cell migration assay, clonogenic assay, cell cycle analysis and qRT-PCR analysis were done in pancreatic cancer cells (MiaPaCa-2) treated with O-CMC-metformin NPs for evaluating its anticancer potential. In vivo biodistribution studies were carried out by NIR imaging of O-CMC-metformin NPs after tagging it with ICG. In vivo biocompatibility of the NPs was assessed by histopathology analysis of organs from mice administered with the NPs.

Results

In vitro cell migration assay showed marginal effect of NPs on migration property of pancreatic cancer cells (MiaPaCa-2). In vitro clonogenic assay established that the O-CMC-metformin NPs reduced colony formation ability of the cancer cells. While cell cycle analysis showed that the O-CMC-metformin NPs had only minor effect on progression of cell cycle in the cancer cells. qRT-PCR analysis exhibited reduced mRNA expression of p21, vanin 1 and MMP9 in pancreatic cancer cells treated with the nanoparticles. In vivo NIR imaging study showed normal biodistribution pattern of the intravenously injected O-CMC-metformin NPs suggesting normal clearance rate of nanoparticles and no adverse toxicity to the organs.

Conclusions

The biocompatible O-CMC-metformin NPs with anticancer potential and capability for normal biodistribution can be beneficial for the treatment of pancreatic cancer.  相似文献   
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Background

Published guidelines regarding radiographic imaging in the evaluation of monosymptomatic primary nocturnal enuresis (MPNE) are not followed. We aimed to evaluate the prevalence of urological abnormalities on renal/bladder ultrasound (RBUS) in children with MPNE and to compare the RBUS findings in children with and without MPNE.

Methods

Retrospective data collection in all children aged 5–17 years seen for the initial evaluation of MPNE. Control group consisted of age- and sex-matched children who had abdominal ultrasound for other than bladder-/kidney-related causes. RBUS findings were analyzed with regard to the need for intervention and/or follow-up.

Results

While abnormalities on RBUS were seen in 12.54 % of enuretic children and in 5.38 % of controls (p?=?0.004), the majority of these findings were clinically insignificant. Of those with abnormalities, only 4 enuretic children (1.43 %) required intervention and 8 (2.87 %) needed follow-up studies. These rates were not significantly different from the controls. However, enuretic children with RBUS abnormalities appear to be more resistant to treatment than enuretic children with normal RBUS (p?=?0.002).

Conclusions

A small proportion of abnormalities seen on RBUS in children with MPNE require intervention and/or further evaluation. The identification of insignificant RBUS findings could lead to unnecessary additional investigations owing to parental concern. Detailed history and a voiding diary may be sufficient in the initial evaluation of children with MPNE, although RBUS may play an important role in patients who are resistant to treatment.  相似文献   
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