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1.
S100A8 and S100A9 are Ca2+ binding proteins that belong to the S100 family. Primarily expressed in neutrophils and monocytes, S100A8 and S100A9 play critical roles in modulating various inflammatory responses and inflammation-associated diseases. Forming a common heterodimer structure S100A8/A9, S100A8 and S100A9 are widely reported to participate in multiple signaling pathways in tumor cells. Meanwhile, S100A8/A9, S100A8, and S100A9, mainly as promoters, contribute to tumor development, growth and metastasis by interfering with tumor metabolism and the microenvironment. In recent years, the potential of S100A8/A9, S100A9, and S100A8 as tumor diagnostic or prognostic biomarkers has also been demonstrated. In addition, an increasing number of potential therapies targeting S100A8/A9 and related signaling pathways have emerged. In this review, we will first expound on the characteristics of S100A8/A9, S100A9, and S100A8 in-depth, focus on their interactions with tumor cells and microenvironments, and then discuss their clinical applications as biomarkers and therapeutic targets. We also highlight current limitations and look into the future of S100A8/A9 targeted anti-cancer therapy.  相似文献   

2.
The storage time and storage temperature might affect stability of oxidative stress biomarkers, therefore, they have to be analyzed after long-term storage of serum samples. The stability of three biomarkers reflecting oxidative stress: reactive oxygen metabolites (ROM) for hydroperoxides, total thiol levels (TTL) for the redox status and biological antioxidant potency (BAP) for the antioxidant status, was investigated at several time points during 60 months of storage at ?20 and ?80?°C. Biomarkers ROM and BAP showed a very good stability during storage for 60 months at both temperatures. In addition, the correlation of the data after 60 months of storage compared with the starting data was very good with correlation coefficients >0.9. The TTL assay showed good results in serum samples stored at ?80?°C, but not in samples stored at ?20?°C. Serum samples for analysis of the set of oxidative stress biomarkers ROM, BAP and TTL can be stored up to 60 months at ?80?°C. ROM and BAP can also be stored at ?20?°C during this period. The present results are very important for the biomarker-related epidemiological studies that make use of biobanks with samples stored for many years and for new project planning, including sample storage conditions.  相似文献   

3.
Samples of barley straw, chopped to 5 cm nominal particle length, were treated with 7.5 g NaOH in 120 ml solution per 100 g dry matter (DM) and either dried immediately after treatment or stored at ?15°C for 24 days prior to drying. The samples were either dried at 100°C in a forced-draught oven, or were freeze-dried. For the samples dried immediately after treatment, incubation in vitro commenced 40 h after treatment. Digestibility in vitro was higher for oven-dried than for freeze-dried samples, particularly when the samples were incubated 40 h after treatment with alkali. Digestibility was also higher for samples which were stored prior to being dried than for those dried directly after treatment with alkali. This suggests that the reaction of alkali with straw continued during the storage of undried material at ?15°C.  相似文献   

4.
S100A2 level changes are related to human periodontitis   总被引:1,自引:0,他引:1  
Periodontitis is an inflammatory disease, which, when severe, can result in tooth loss, that affects the quality of life. S100A2 was previously identified as a component of gingival crevicular fluid (GCF) via proteome analysis, but it has not been investigated whether S100A2 plays a role in periodontitis. In this study, we analyzed mRNA expression of S100A2 in gingival tissues from normal and classified periodontal disease patients and compared it to that of S100A8 and S100A9. Quantitative real time-PCR revealed that the mRNA expression levels of S100A2, S100A8, and S100A9 were significantly upregulated in gingival tissues with gingivitis, moderate periodontitis, and severe periodontitis compared to normal tissues. In addition, S100A2 proteins in GCF and the conditioned media of lipopolysaccharide (LPS)-treated Jurkat cells were confirmed by ELISA. S100A2 protein levels were significantly higher in GCF in gingivitis and moderate periodontitis groups than in normal groups. S100A2 mRNA expression and protein secretion were also increased by LPS stimulation. Based on the up-regulation of S100A2 in LPS-stimulated immune cells, gingival tissues and GCF from periodontal disease groups, we conclude that S100A2 is a functional component in the immune response during periodontitis and may serve as a potential biomarker for periodontitis.  相似文献   

5.
The effects of freezing on the proteolysis of beef during storage at 4°C after being thawed was investigated.

A sarcoplasmic 32-kDa protein in frozen as well as unfrozen beef decreased rapidly during storage at 4°C, and a more than 100-kDa protein appeared in both beef samples. And the increment of peptides in the frozen beef during the storage at 4°C was larger than that in the unfrozen beef, suggesting that the proteolysis was faster during the storage of the former than the latter. However, its increment in the frozen beef for 10 weeks during the storage at 4°C became smaller than that of the one frozen for less than 5 weeks.

To discover an indicator for evaluation of the conditioning of frozen and unfrozen beef, peptides produced during the storage of beef at 4°C were surveyed. A peptide, APPPPAEVPEVHEEV, was detected and seemed to be available as an indicator in the conditioning of beef.  相似文献   

6.
Survival of 5 strains of Campylobacter jejuni/coli in ground beef liver stored at 4° C and at –20° C was studied. After 6 days of storage at 4° C the beef liver was spoiled, which was indicated by APG log 7.25 and lactobacilli count log 7.0. During this storage Campylobacter counts decreased only slightly. After 12 weeks of storage at –20° C Campylobacter counts decreased by 2–3 logs in frozen ground beef liver. Survival of 4 strains of C. jejuni/coli on frozen broiler carcasses was also studied. Two inoculation levels, 103–104/g and 104–105/g were used. On frozen broiler carcasses Campylobacter counts decreased by 0.5–2.0 logs during 12 weeks at –20° C.  相似文献   

7.
Soybean seed samples inoculated with spores of Aspergillus ruber were stored for 20 to 140 days at 25 ± 1 °C with moisture content varying from 11.3% to 17.7%. Seeds were colonised by the fungus within 20 days at all moisture levels. Ergosterol concentration in seeds increased with time of storage, being slow in samples with moisture content of 11.3% to 13.1% and more rapidly in those with higher moisture content. Free fatty acid (FFA) content also increased following the pattern of ergosterol. Equations were used to predict minimum safe storage period of the seeds at 25 °C. The rise in FFA is due to increase of A. ruber mass within the seed. Fungal growth did not affect fatty acids profiles or iodine index of the extracted oil. The results suggest revision of the present recommendations regarding seed moisture during storage. The FFA concentration of a seed lot can be used as a sensitive indicator of seed deterioration due to storage fungi. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   

8.
Hordeumin stored at –40 to –80oC in 1% HCI–methanol suffered neither from color reduction nor discoloration. After heating at 80°C for 60 min, hordeumin showed a pigment retention rate of 100%. This characteristic is because the pigment is a composite high-molecular weight compound consisting of anthocyanins and polyphenols, It was determined, however, that discoloration and browning occurred more rapidly than color reduction during storage and heating of the pigment.  相似文献   

9.
S100A11 protein is a member of the S100 family containing two EF‐hand motifs. It undergoes phophorylation on residue T10 after cell stimulation such as an increase in Ca2+ concentration. Phosphorylated S100A11 can be recognized by its target protein, nucleolin. Although S100A11 is initially expressed in the cytoplasm, it is transported to the nucleus by the action of nucleolin. In the nucleus, S100A11 suppresses the growth of keratinocytes through p21CIP1/WAF1 activation and induces cell differentiation. Interestingly, the N‐terminal fragment of S100A11 has the same activity as the full‐length protein; i.e. it is phosphorylated in vivo and binds to nucleolin. In addition, this fragment leads to the arrest of cultured keratinocyte growth. We examined the solution structure of this fragment peptide and explored its structural properties before and after phosphorylation. In a trifluoroethanol solution, the peptide adopts the α‐helical structure just as the corresponding region of the full‐length S100A11. Phosphorylation induces a disruption of the N‐capping conformation of the α‐helix, and has a tendency to perturb its surrounding structure. Therefore, the phosphorylated threonine lies in the N‐terminal edge of the α‐helix. This local structural change can reasonably explain why the phosphorylation of a residue that is initially buried in the interior of protein allows it to be recognized by the binding partner. Copyright © 2008 European Peptide Society and John Wiley & Sons, Ltd.  相似文献   

10.
Seeds with a water‐impermeable seed coat and a physiologically dormant embryo are classified as having combinational dormancy. Seeds of Sicyos angulatus (burcucumber) have been clearly shown to have a water‐impermeable seed coat (physical dormancy [PY]). The primary aim of the present study was to confirm (or not) that physiological dormancy (PD) is also present in seeds of S. angulatus. The highest germination of scarified fresh (38%) and 3‐month dry‐stored (36%) seeds occurred at 35/20°C. The rate (speed) of germination was faster in scarified dry‐stored seeds than in scarified fresh seeds. Removal of the seed coat, but leaving the membrane surrounding the embryo intact, increased germination of both fresh and dry‐stored seeds to > 85% at 35/20°C. Germination (80–100%) of excised embryos (both seed coat and membrane removed) occurred at 15/6, 25/15 and 35/20°C and reached 95–100% after 4 days of incubation at 25/15 and 35/20°C. Dry storage (after‐ripening) caused an increase in the germination percentage of scarified and of decoated seeds at 25/15°C and in both germination percentage and rate of excised embryos at 15/6°C. Eight weeks of cold stratification resulted in a significant increase in the germination of scarified seeds at 25/15 and 35/20°C and of decoated seeds at 15/6 and 25/15°C. Based on the results of our study and on information reported in the literature, we conclude that seeds of S. angulatus not only have PY, but also non‐deep PD, that is, combinational dormancy (PY + PD).  相似文献   

11.
The protein composition of gingival crevicular fluid (GCF) may reflect the pathophysiology of periodontal diseases. A standard GCF proteomic pattern of healthy individuals would serve as a reference to identify biomarkers of periodontal diseases by proteome analyses. However, protein profiles of GCF obtained from apparently healthy individuals have not been well explored. As a step toward detection of proteomic biomarkers for periodontal diseases, we applied both gel-based and gel-free methods to analyze GCF obtained from healthy subjects as compared with supragingival saliva. To ensure optimized protein extraction from GCF, a novel protocol was developed. The proteins in GCF were extracted with high yield by urea buffer combined with ultrafiltration and the intensity of spots with supragingival saliva and GCF was compared using agarose two-dimensional electrophoresis. Eight protein spots were found to be significantly more intense in GCF. They included superoxide dismutase 1 (SOD1), apolipoprotein A-I (ApoA-I), and dermcidin (DCD). Moreover, GCF proteins from healthy subjects were broken down into small peptide fragments and then analyzed directly by LC-MS/MS analysis. A total of 327 proteins including ApoA-I, SOD1, and DCD were identified in GCF. These results may serve as reference for future proteomic studies searching for GCF biomarkers of periodontal diseases.  相似文献   

12.
The ability of Rhizoctonia solani AG‐1 IA, the causal agent of rice sheath blight, to survive in diseased rice straw and as sclerotia and mycelia was investigated. After storage for 10 months at 4°C, 25°C and non‐air‐conditioned natural room temperature (NRT, temperature range from 6°C to 35°C), sclerotia placed inside a desiccator, soaked in sterile water or immersed in wet paddy soil were viable. In contrast, only 15% of sclerotia in dry paddy soil survived. Survival of mycelia was severely affected by temperature and humidity. After 10 months in a desiccator at 4°C, 55% of mycelia samples could survive, whereas at 25°C and NRT, mycelial samples survived for only 7 and 5 months, respectively. However, mycelia stored in sterile water at constant temperatures (4°C or 25°C) survived for 10 months. A certain amount of UV radiation had no obvious effect on the survival of sclerotia or mycelia. The survival rate of the fungus in diseased rice straw stored for 16 months could reach 100% at 4°C, 50% at 25°C and 35% at NRT. The survival rates of the pathogen in diseased rice straw buried in dry, wet and flooded paddy soils after 10‐month storage at NRT were 75, 100 and 100%, respectively, indicating that soil humidity is a crucial factor for the survival of this fungus.  相似文献   

13.
Fifteen species of marine invertebrate commonly occurring in the near-shore environment of Rothera base, Antarctica, were used to test tissue sample storage protocols with regard to preservation of RNA integrity. After animal collection, the tissues were either immediately extracted for RNA or stored at −80°C after having been, either directly flash frozen in liquid nitrogen or preserved in a commercial RNA storage solution, for extraction in the UK. In four cases, direct flash freezing produced enhanced RNA integrity compared with samples in the commercial storage solution. A subset of samples were further tested for the preferred temperature of storage in the commercial reagent. RNA integrity was well preserved at both +4 and −20°C over periods of 2 months, but degradation was rapid in tissues stored at room temperature. Eight out of the fifteen species only produced a single ribosomal band on gel electrophoresis. This survey provides a guide for tissue transport of Polar cold water marine invertebrates.  相似文献   

14.
Aims: To determine the efficacy of X‐ray processes in inactivating L. monocytogenes levels in smoked catfish during storage at 5°C and to determine the effects of X‐ray doses on controlling the growth of spoilage bacteria on smoked catfish during storage at 5°C for up to 5 weeks. Methods and Results: Smoked catfish fillets inoculated with L. monocytogenes were treated with 0·0–2·0 kGy X‐ray and stored at 5°C for 5 weeks. The negative controls (uninoculated/untreated) and uninoculated samples treated with the lowest (0·1 kGy) and highest (2·0 kGy) doses were stored at 5°C and tested for psychrotrophs count during the 5 weeks of storage. The initial L. monocytogenes population on smoked catfish was significantly (P < 0·05) reduced to undetectable level by a treatment of 1·0 kGy or higher. The initial psychrotrophs count on smoked catfish was significantly reduced from 4·7 CFU g?1 to below the detectable level by a treatment with 2·0 kGy. Conclusions: Smoked catfish treated with 2·0 kGy X‐ray had no detectable L. monocytogenes throughout 35 days of storage at 5°C. A treatment with 2·0 kGy X‐ray also kept the levels of psychrotrophs in the smoked catfish within the acceptable level until 35 days. Significance and Impact of the Study: The results of this investigation indicate that X‐ray at 2·0 kGy can eliminate L. monocytogenes and extend the shelf life of smoked catfish stored at refrigeration temperature.  相似文献   

15.
This study aimed to discover the novel noninvasive biomarkers for the diagnosis of pulmonary tuberculosis (TB). We applied iTRAQ 2D LC‐MS/MS technique to investigate protein profiles in patients with pulmonary TB and other lung diseases. A total of 34 differentially expressed proteins (24 upregulated proteins and ten downregulated proteins) were identified in the serum of pulmonary TB patients. Significant differences in protein S100‐A9 (S100A9), extracellular superoxide dismutase [Cu‐Zn] (SOD3), and matrix metalloproteinase 9 (MMP9) were found between pulmonary TB and other lung diseases by ELISA. Correlations analysis revealed that the serum concentration of MMP9 in the pulmonary TB was in moderate correlation with SOD3 (r = 0.581) and S100A9 (r = 0.471), while SOD3 was in weak correlation with S100A9 (r = 0.287). The combination of serum S100A9, SOD3, and MMP9 levels could achieve 92.5% sensitivity and 95% specificity to discriminate between pulmonary TB and healthy controls, 90% sensitivity and 87.5% specificity to discriminate between pulmonary TB and pneumonia, and 85% sensitivity and 92.5% specificity to discriminate between pulmonary TB and lung cancer, respectively. The results showed that S100A9, SOD3, and MMP9 may be potential diagnostic biomarkers for pulmonary TB, and provided experimental basis for the diagnosis of pulmonary TB.  相似文献   

16.
Fecal steroid analysis is a powerful tool that can provide important information on the health, physiology, and reproductive status of nondomestic species. However, studying free‐ranging animals requires that feces be stored and transported from the collection site to the laboratory in a manner that prevents degradation or alteration of steroid metabolites. To determine the effects of different handling and storage methods on fecal steroids, 30 fresh fecal samples from five captive cheetahs were collected, thoroughly mixed, separated into aliquots, and processed (stored or dried) under different conditions. Concentrations of gonadal and adrenal steroid hormones were analyzed in feces stored frozen at –20°C or at room temperature in 95% ethanol. Both frozen and ethanol‐stored aliquots were desiccated using a lyophilizer, solar oven, or conventional oven. The steroid values from aliquots stored and desiccated using the different methods were compared to those obtained using the optimal storage method of freezing at –20°C and desiccating in a lyophilizer (control). Concentrations of corticoid, estrogen, progestagen, and androgen metabolites in fecal extracts were quantified by radioimmunoassay. Androgen metabolite concentrations were not significantly affected (P > 0.05) by storage or drying methods. Fecal samples stored at room temperature in ethanol and lyophilized also had steroid concentrations that did not differ (P > 0.05) from controls. However, the concentrations of corticoid and estrogen metabolites were significantly lower (P < 0.05), and progestagen metabolites were significantly higher (P < 0.05) in samples desiccated in solar and conventional ovens without regard to storage method. These results suggest that storage of fecal samples at room temperature in ethanol is the best alternative to freezing for subsequent analysis of steroid hormone concentrations. Differences in measured concentrations of hormones in oven‐desiccated samples could be due to hormone degradation or shifts in the immunodominant metabolite. Therefore, validation of storage and processing techniques should be included in the development of any new fecal steroid analysis methodology. Zoo Biol 21:215–222, 2002. © 2002 Wiley‐Liss, Inc.  相似文献   

17.
A new adenosine nucleotide analog suitable for the Pyrosequencing method is presented. The new analog, 7‐deaza‐2′‐deoxyadenosine‐5′‐triphosphate (c7dATP), has virtually the same low substrate specificity for luciferase as the currently used analog, 2′‐deoxyadenosine‐5′‐O‐(1‐thiotriphosphate) (dATPαS). The inhibitory effect dATPαS displays on the nucleotide degrading activity of apyrase was reduced significantly by substituting the c7dATP for the dATPαS. Both analogs show high stability after long time storage at + 8°C. Furthermore, with the new nucleotide a read length of up to 100 bases was obtained for several templates from fungi, bacteria and viruses.  相似文献   

18.
S100B and S100A10 are dimeric, EF‐hand proteins. S100B undergoes a calcium‐dependant conformational change allowing it to interact with a short contiguous sequence from the actin‐capping protein CapZ (TRTK12). S100A10 does not bind calcium but is able to recruit the N‐terminus of annexin A2 important for membrane fusion events, and to form larger multiprotein complexes such as that with the cation channel proteins TRPV5/6. In this work, we have designed, expressed, purified, and characterized two S100‐target peptide hybrid proteins comprised of S100A10 and S100B linked in tandem to annexin A2 (residues 1–15) and CapZ (TRTK12), respectively. Different protease cleavage sites (tobacco etch virus, PreScission) were incorporated into the linkers of the hybrid proteins. In situ proteolytic cleavage monitored by 1H‐15N HSQC spectra showed the linker did not perturb the structures of the S100A10‐annexin A2 or S100B‐TRTK12 complexes. Furthermore, the analysis of the chemical shift assignments (1H, 15N, and 13C) showed that residues T102‐S108 of annexin A2 formed a well‐defined α‐helix in the S100A10 hybrid while the TRTK12 region was unstructured at the N‐terminus with a single turn of α‐helix from D108‐K111 in the S100B hybrid protein. The two S100 hybrid proteins provide a simple yet extremely efficient method for obtaining high yields of intact S100 target peptides. Since cleavage of the S100 hybrid protein is not necessary for structural characterization, this approach may be useful as a scaffold for larger S100 complexes.  相似文献   

19.
Ribonuclease (RNase), which often represents molecular biological contamination, is a thermostable enzyme. When RNase is heated at 121°C by autoclave sterilization for 20 min, it does not lose its activity. However, the nature of the molecular events by which the irreversible denaturation occurs remains unknown. The purpose of this study was to elucidate the molecular mechanisms of irreversible thermal denaturation of RNase A and to develop an advanced sterilization method using soft‐hydrothermal processing, which has the advantages of improved safety and cost‐efficiency. The enzymatic activity of RNase was measured using polyacrylamide gel electrophoresis with torula yeast RNA. We evaluated the temperature and time course of irreversible thermoinactivation of RNase by normal autoclaving, hot‐air sterilization, and soft‐hydrothermal processing that had been controlled to the desired steam saturation ratio. The results indicated that RNase A was deactivated by autoclave sterilization (121°C, 20 min) immediately after treatment, but was reactivated over time. Hot‐air sterilization (180°C, atmospheric pressure, 60 min) produced results similar to that of autoclave sterilization. In contrast, RNase A was irreversibly thermoinactivated by soft‐hydrothermal processing (110°C, 20 min) at 100% steam saturation ratio. We also determined that the mechanism of irreversible thermoinactivation of RNase A involved hydrolysis and deamidation under this condition at a steam saturation ratio of more than 100%. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2009  相似文献   

20.
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