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1.
The noninvasive sampling of dermal interstitial fluid (ISF) for the monitoring of clinical biomarkers is a greatly appealing area of research. The identification of molecular biomarkers in biological fluids has been accelerated with -omics analyses but remains limited in ISF because of its time-consuming and complex extraction process. Here, the generation of microneedle (MN) patches made of superabsorbent acrylate-based hydrogels for the rapid sampling of dermal ISF is described to explore its proteome. In depth, iterative optimization allows the identification of novel acrylate-based compositions with the required chemical, mechanical, and biocompatibility properties allowing proteomic analysis of the extracted ISF for the first time after sampling with swelling MNs. The generated MN arrays show no cytotoxic effect, successfully cross the stratum corneum, and can collect up to 6 µL of dermal ISF in 10 min in vivo. Proteomics lead to the detection of 176 clinically relevant biomarkers in the collected samples validating the use of ISF as a relevant bodily fluid for disease monitoring and diagnostic. Importantly, it is discovered that extraction fingerprint is strongly dependent on the MNs chemistry, and thus specific biomarkers could be selectively extracted by tuning the composition of the patch, making the system versatile and specific.  相似文献   
2.
Immune sensorineural hearing loss is manifested in several systemic immune diseases. Although hearing loss has been previously documented in patients with Sj?gren's syndrome (SS), the effect of SS on hearing is unclear. This prospective study was designed to assess the presence of hearing loss in 14 patients with SS and, if sensorineural hearing loss was present, to determine if the hearing loss was immune-mediated. Patients were evaluated with basic audiologic tests as well as for cellular immune inner ear reactivity as measured by the lymphocyte transformation test (LTT). Three patients had evidence of sensorineural hearing loss. Two patients had a positive LTT without evidence of sensorineural hearing loss. This preliminary study suggests that SS may not directly cause sensorineural hearing loss, immuno-mediated or otherwise.  相似文献   
3.
The growth structure of MgF2 and NdF3 films grown on polished CaF2(111) substrates deposited by molecular beam deposition has been investigated using transmission electron microscopy (TEM) of microfractographical and surface replications as well as cross-sectional TEM, atomic force microscopy, packing density, and absorption measurements. It has been shown that by taking advantage of ultrahigh vacuum environments and a special stratification property of MgF2 and NdF3 films, the preparation of nanocrystalline films of high packing density and low optical absorption is possible at a substrate temperature of 425 K.  相似文献   
4.
The purple (Sulphur) phototrophic bacterium, Thiocapsa roseopersicina BBS contains several [NiFe] hydrogenases, of which two are membrane bound. Mutant T. roseopersicina cells, carrying deletions in both gene clusters showed hydrogenase activity. This activity was located in the cytoplasm. The structural gene cluster hoxEFUYH was identified and sequenced. In addition, genes homologous to hupUV/hoxBC, the hydrogen sensing hydrogenase have been identified and sequenced.Regulation of hydrogenase biosynthesis was studied in detail for HydSL (renamed HynSL). A random mutagenesis system was optimised for T. roseopersicina. One of the mutations was in a gene similar to that coding for the HypF proteins in other organisms. Inactivation of the hypF gene resulted in a 60-fold increase in hydrogen evolution under nitrogen fixing conditions. In addition to hypF, the following accessory genes were identified: hydD, hupK, hypC1, hypC2, hypDE. Characterisation of the corresponding gene products and search for additional accessory genes are in progress.  相似文献   
5.
Increasing the susceptibility of tumor cells to apoptotic cell death following chemotherapy is of importance to the outcome of cancer treatment. Although the tumor suppressor gene p53 is required for efficient induction of apoptosis by chemotherapeutic agents, it is not the only apoptosis mediator gene. The molecular mechanisms mediating apoptosis following chemotherapy via p53-dependent or p53-independent pathways remain unclear. We show here that cis-diamminedichloroplatinum (cisplatin) induces the expression of interleukin-1 beta-converting enzyme (ICE), a mammalian homologue of the Caenorhabditis elegans cell death gene ced-3, in murine and human malignant glioma cells during apoptosis regardless of their p53 status. Furthermore, overexpression of the murine ICE gene induces apoptosis in these tumor cells. The apoptosis induced by cisplatin treatment or murine ICE overexpression can be suppressed by the tetrapeptide ICE inhibitor Ac-YVAD-CMK or the apoptosis inhibitors bcl-2 or bcl-2-related bcl-XL gene. These findings suggest that ICE may mediate apoptosis induced by chemotherapy, and its induction could represent a novel approach for the effective treatment of malignant glioma.  相似文献   
6.
7.
The limited effect of current medications on neuropathic pain (NP) has initiated large efforts to develop effective treatments. Animal studies showed that glycine transporter (GlyT) inhibitors are promising analgesics in NP, though concerns regarding adverse effects were raised. We aimed to study NFPS and Org-25543, GlyT-1 and GlyT-2 inhibitors, respectively and their combination in rat mononeuropathic pain evoked by partial sciatic nerve ligation. Cerebrospinal fluid (CSF) glycine content was also determined by capillary electrophoresis. Subcutaneous (s.c.) 4 mg/kg NFPS or Org-25543 showed analgesia following acute administration (30–60 min). Small doses of each compound failed to produce antiallodynia up to 180 min after the acute administration. However, NFPS (1 mg/kg) produced antiallodynia after four days of treatment. Co-treatment with subanalgesic doses of NFPS (1 mg/kg) and Org-25543 (2 mg/kg) produced analgesia at 60 min and thereafter meanwhile increased significantly the CSF glycine content. This combination alleviated NP without affecting motor function. Test compounds failed to activate G-proteins in spinal cord. To the best of our knowledge for the first time we demonstrated augmented analgesia by combining GlyT-1 and 2 inhibitors. Increased CSF glycine content supports involvement of glycinergic system. Combining selective GlyT inhibitors or developing non-selective GlyT inhibitors might have therapeutic value in NP.  相似文献   
8.
In pattern mining and association rule mining, there is a variety of algorithms for mining frequent closed itemsets (FCIs) and frequent generators (FGs), whereas a smaller part further involves the precedence relation between FCIs. The interplay of these three constructs and their joint computation have been studied within the formal concept analysis (FCA) field yet none of the proposed algorithms is scalable. In frequent pattern mining, at least one suite of efficient algorithms has been designed that exploits basically the same ideas and follows the same overall computational schema. Based on an in-depth analysis of the aforementioned interplay that is rooted in a fundamental duality from hypergraph theory, we propose a new schema that should enable for a more parsimonious computation. We exemplify the new schema in the design of Snow-Touch, a concrete FCI/FG/precedence miner that reuses an existing algorithm, Charm, for mining FCIs, and completes it with two original methods for mining FGs and precedence, respectively. The performance of Snow-Touch and of its closest competitor, Charm-L, were experimentally compared using a large variety of datasets. The outcome of the experimental study suggests that our method outperforms Charm-L on dense data while on sparse one the trend is reversed. Furthermore, we demonstrate the usefulness of our method and the new schema through an application to the analysis of a genome dataset. The initial results reported here confirm the capacity of the method to focus on significant associations.  相似文献   
9.
To determine antioxidative effects of ferulic acid and esterified ferulic acids, these compounds were added to soybean oils (SBO), which were evaluated for oxidative stability and frying stability. Additives included feruloylated MAG and DAG (FMG/FDG), ferulic acid, ethyl ferulate, and TBHQ. After frying tests with potato chips, oils were analyzed for retention of additives and polar compounds. Chips were evaluated for hexanal and rancid odor. After 15 h frying, 71% of FMG/FDG was retained, whereas 55% of ethyl ferulate was retained. TBHQ and ferulic acid levels were 6% and <1%, respectively. Frying oils with ethyl ferulate or TBHQ produced significantly less polar compounds than SBO with no additives. Chips fried in SBO with TBHQ or ferulic acid had significantly lower amounts of hexanal and significantly less rancid odor after 8 d at 60°C than other samples. Oils were also aged at 60°C, and stability was analyzed by PV, hexanal, and rancid odor. Oils with TBHQ or FMG/FDG had significantly less peroxides and hexanal, and a lower rancid odor intensity than the control. FMG/FDG inhibited deterioration at 60°C, whereas ethyl ferulate inhibited the formation of polar compounds in frying oil. Ferulic acid acted as an antioxidant in aged fried food. TBHQ inhibited oil degradation at both temperatures. Presented at the 94th AOCS Meeting & Expo, Kansas City, MO, May 4–7, 2003.  相似文献   
10.
Rare association rules correspond to rare, or infrequent, itemsets, as opposed to frequent ones that are targeted by conventional pattern miners. Rare rules reflect regularities of local, rather than global, scope that can nevertheless provide valuable insights to an expert, especially in areas such as genetics and medical diagnosis where some specific deviations/illnesses occur only in a small number of cases. The work presented here is motivated by the long-standing open question of efficiently mining strong rare rules, i.e., rules with high confidence and low support. We also propose an efficient solution for finding the set of minimal rare itemsets. This set serves as a basis for generating rare association rules.  相似文献   
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