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1.
Ethidium bromide monoazide (EMA) was utilized to selectively allow conventional PCR amplification of target DNA from viable but not dead cells from a broth culture of bacterial mixed flora derived from cod fillets. The universal primers designated DG74 and RW01 that amplify a 370-bp sequence of a highly conserved region of all eubacterial 16S rDNA were used for the PCR. The use of 10 μg/ml or less of EMA did not inhibit the PCR amplification of DNA derived from viable bacteria. The minimum amount of EMA to completely inhibit the PCR amplification of DNA derived from dead bacterial cells was 0.8 μg/ml. Amplification of target DNA from only viable cells in a suspension with dead cells was selectively accomplished by first treating the cells with 1 μg/ml of EMA. A standard curve was generated relating the intensity of fluorescence of DNA bands to the log of CFU of mixed bacterial cultures for rapidly assessing the number of genomic targets per PCR derived from the number of CFU. A linear range of DNA amplification was exhibited from 1 × 102 to 1 × 105 genomic targets per PCR. The viable/dead cell discrimination with the EMA-PCR method was evaluated by comparison with plate counts following freezing and thawing. Thawing frozen cell suspensions initially containing 1 × 105 CFU/ml at 4, 20, and 37 °C yielded a 0.8 log reduction in the number of viable cells determined by both plate counts and EMA-PCR. In contrast, thawing for 5 min at 70 °C resulted in a 5 log reduction in CFU derived from plate counts (no CFU detected) whereas the EMA-PCR procedure resulted in only a 2.8 log reduction in genomic targets, possibly reflecting greater damage to enzymes or ribosomes at 70 °C to a minority of the mixed population compared to membrane damage.  相似文献   

2.
Gangetic delta is considered as the homeland of cholera, which is thought to be influenced by changes in populations of estuarine Vibrio cholerae. We aim to identify the environmental, biotic and abiotic driving forces influencing the V. cholerae dynamics in riverine-estuarine environment of southern deltaic Bengal. Cultivable Vibrio count (CVC) ranged between 1 and 103 colony forming units (CFU)/mL at a salinity gradient of 1.9–30 practical salinity unit (PSU). Increased water temperatrure during summer influences the higher CVC followed by a sudden fall along with the onset of monsoon upto winter. While summer V. cholerae O1 peak (50–100 CFU/mL) can be associated with higher water temperature (P < 0.05) and higher turbidity (P < 0.005); sharp fall during monsoon (15–45 CFU/mL) is attributed to reduced salinity (25–2.5 PSU). Plankton attached V. cholerae O1 varied between 10 and 1000 CFU/mL with a highest peak at winter followed by summer and monsoon. Prevalence of toxigenic V. cholerae O1 in low salinity (2–7.5 PSU) during monsoon identifies that high water temperature (>25 °C), higher turbidity (>100 NTU) and lower salinity plays the pivotal role in toxicity acquisition. Present investigation establishes the role of Sundarban mangrove, where V. cholerae exist in an avirulent condition. During migration towards low saline inland system, V. cholerae pool possibly acquires toxin genes under the influence of environmental factors. Planktonic attachment is possibly a survival strategy at adverse condition, when they do not acquire any toxin gene. Seasonal V. cholerae dynamics has been thoroughly established in environmental settings of high saline mangrove and brackish water flowing to inland low saline condition.  相似文献   

3.
Characteristics of goat milk collected from seven small and medium enterprises (SMEs) in Greece, France and Portugal were compared. Results of microbiological, biochemical and technological characteristics (whey draining capacity after lactic or rennet coagulation, acidification aspects, and heat stability) of goat milk with identical and standardised techniques are discussed in relation to effects on technological processes and quality of final products. Results revealed variability of goat milk characteristics collected from the different European areas. Hygienically, goat milk production conditions in Greece and Portugal, under extensive breeding systems were: total bacteria—3.6×107 and 4×107 CFU/ml; coliforms—1.8×106 and 2.5×106 CFU/ml; staphylococci coagulase+—1.7×105 and 7.6×104 CFU/ml, respectively. For France, using intensive breeding systems, microbiological quality was: total bacteria—1.08×105 CFU/ml; coliforms—1.40×102 CFU/ml; staphylococci coagulase+—2.75×102 CFU/ml. Goat milk from Greek farms had the highest fat and protein contents: 51.4 and 37.0 g/kg, compared to goat milk in France: 36.5 and 32.5 g/kg, respectively. Portuguese goat milk was intermediate: 42.7 and 34.9 g/kg, respectively.Regarding technological aspects, Greek and Portuguese milks showed poor whey draining capacity and Greek milks presented low heat stability (100.5 °C on average) but a good propensity to acidify. Systems of production of goat milk, ways of transport of raw goat milk, and the procedures applied inside factories regarding receiving and storage of the raw goat milk are discussed and should be useful for the definition of technological adaptations, that are necessary for best milk and product quality.  相似文献   

4.
《Process Biochemistry》2007,42(2):267-270
Boza is a low-alcohol beverage produced from the fermentation of barley, oats, millet, maize, wheat or rice. The number of lactic acid bacteria isolated from three boza samples ranged from 9 × 106 to 5 × 107 CFU/mL. Carbohydrate fermentation reactions and PCR with species-specific primers classified the isolates as Lactobacillus paracasei subsp. paracasei, Lactobacillus pentosus, Lactobacillus plantarum, Lactobacillus brevis, Lactobacillus rhamnosus and Lactobacillus fermentum. No filamentous fungi were isolated. Yeasts were isolated from two of the three boza samples, with cell numbers ranging from 1.3 × 102 to 1.8 × 103 CFU/mL. Results obtained from sequencing of the D1/D2 rDNA region identified the yeasts as Candida diversa, Candida inconspicua, Candida pararugosa, Issatchenkia orientalis, Pichia fermentans, Pichia guillliermondii, Pichia norvegensis, Rhodotorula mucilaginosa and Torulaspora delbrueckii. C. inconspicua has been isolated from human sputum and tongue and is an opportunistic pathogen. R. mucilaginosa is also an opportunistic pathogen implicated in fungaemia, endocarditis and meningitis. P. norvegensis has been associated with septicaemia in humans. Saccharomyces cerevisiae, commonly associated with fermented beverages, has not been detected in any of the boza samples, despite enrichment.  相似文献   

5.
Tannery effluent treated with aquatic macrophyte Vallisneria spiralis L. for 14 d showed significant improvement in physico-chemical properties and reduction in Cr concentration. Accumulation of Cr was found maximum in roots (358 μg g?1dw) as compared to shoot (62 μg g?1dw) of the plant. A laboratory scale composter was designed with the objectives to investigate the physico-chemical changes and role of microbes in stabilization and transformation of Cr in the composting material. Results revealed that the composting process was quick within 7–21 d as indicated by peak time for various physico-chemical parameters and drop in C/N ratio up to acceptable limit. The profile of microbial communities indicated that population of anaerobic, aerobic and nitrifying bacteria increased quickly at the initial phase, and reached a peak level of 4.2 × 106, 9.78 × 108 and 9.32 × 109 CFU g?1, respectively at 21 d; while population of actinomycetes and fungi was found maximum i.e. 3.29 × 107 and 9.7 × 106 CFU g?1, respectively, after 35 d of composting. Overall bacterial population dominated over the actinomycetes and fungi during the composting process. Cr(VI) was transformed to Cr(III) due to the microbial activity during the process. Sequential extraction of Cr fractionation showed its stabilization via changing into organic matter-bound and residual fractions during the composting.  相似文献   

6.
Purpose and methodsMicrobial tolerance represents a diminished pro-inflammatory response following repeated stimulation by a host of pathogen-associated molecular patterns (PAMPs) of varying origins. Toll-like receptors (TLRs) have been centrally implicated in the development of tolerance. The purpose of this study was to investigate the impact of tolerance in a previously described murine model.C57BL/6 mice were pretreated intraperitoneally with phosphate buffered saline (PBS), heat-killed Klebsiella 2 × 108 CFU (hkKlebsiella), LPS 10 mg/kg (LPS 10), or BLP 10 mg/kg (BLP 10). Following pretreatment, peritonitis was induced 24 h later using 103 intraperitoneal Klebsiella CFU. Peritoneal concentrations of TNF-α, IL-10 and nitric oxide (NO), as well as characteristic cell patterns, were determined. Long-term consequences of microbial tolerance were assessed by measuring survival and weight-loss.ResultsFollowing in vitro stimulation with Klebsiella 105 and 103 CFU, TNF-α and IL-10 secretion were diminished in macrophages harvested from mice pretreated with hkKlebsiella, LPS 10 and BLP 10. Pretreated animals had significantly lower bacterial counts. Conversely, local NO levels were elevated. Survival was not different between the groups.ConclusionPretreatment with TLR ligands induced microbial tolerance, with reduced peritoneal cytokine concentrations and enhanced early bacterial clearance. However, this did not translate into improved survival.  相似文献   

7.
An 88-year-old Japanese woman was referred to our hospital due to a one-month history of face edema, aphagia, shortness of breath, and skin rush over almost her entire skin. She had no abdominal symptoms. Her peripheral blood count showed a white blood cell (WBC) count of 27.1 × 109/L with 82.1% eosinophils. Serum non-specific Immunoglobulin E was within a normal range. Soluble interleukin-2 receptor was elevated to 4200 U/mL. At first, her eosinophil count was so high that we suspected she had an eosinophilic leukemia or hypereosinophilic syndrome. After admission, cysts of Giardia duodenalis (G. duodenalis) were detected in the patient's feces by microscopic analysis, then she was diagnosed with giardiasis, and 750 mg per day of metronidazole was administered for seven days. Her WBC count decreased to 6.0 × 109/L with 10% eosinophils, and her systemic symptoms improved. At that time her serum IL-5 was within a normal range. A few months later, the patient again complained of skin rush, and G. duodenalis was once again found in her feces. Her serum IL-5 was elevated to 751 pg/mL. Metronidazole was administered for two weeks, and her eosinophil count decreased. G. duodenalis is a protozoan parasite, and it is one of the most common waterborne transmission gastrointestinal parasites in the world. G. duodenalis rarely causes hypereosinophilia. To our knowledge, this is the first case report of giardiasis with extreme hypereosinophilia and severe systemic symptoms.  相似文献   

8.
Studies on the microbial ecology of gut microbiota in bats are limited and such information is necessary in determining the ecological significance of these hosts. Short-nosed fruit bats (Cynopterus brachyotis brachyotis) are good candidates for microbiota studies given their close association with humans in urban areas. Thus, this study explores the gut microbiota of this species from Peninsular Malaysia by means of biochemical tests and 16S rRNA gene sequences analysis. The estimation of viable bacteria present in the stomach and intestine of C. b. brachyotis ranged from 3.06 × 1010 to 1.36 × 1015 CFU/ml for stomach fluid and 1.92 × 1010 to 6.10 × 1015 CFU/ml for intestinal fluid. A total of 34 isolates from the stomach and intestine of seven C. b. brachyotis were retrieved. A total of 16 species of bacteria from eight genera (Bacillus, Enterobacter, Enterococcus, Escherichia, Klebsiella, Pantoea, Pseudomonas and Serratia) were identified, Enterobacteriaceae being the most prevalent, contributing 12 out of 16 species isolated. Most isolates from the Family Enterobacteriaceae have been reported as pathogens to humans and wildlife. With the possibility of human wildlife transmission, the findings of this study focus on the importance of bats as reservoirs of potential bacterial pathogens.  相似文献   

9.
The Faraday traditional healers' trading market is the hub of the medicinal plant trade in Johannesburg, South Africa. Modes of harvesting, transporting, storage and distribution of medicinal plants render them susceptible to microbial attack, and thereby make customers, especially patients with compromised immune systems, vulnerable to infections that could increase morbidity and mortality. This study evaluated the microbial contamination on five frequently used traditional medicinal plant species sold by traders in the Faraday market. Bacterial contamination was determined using serial macro dilutions, spread plate and streak plate techniques. Fifteen bacterial contaminants were identified, the most recurrent being Pantoea sp. and five strains of Bacillus spp. (non-pathogenic). There was little variation between contamination levels of the five different traders, and the mean CFU/g per species ranged from 3.03 × 104 (Hypoxis sp.) to 4.22 × 105 (Hydnora abyssinica). While there was no overall significant levels of contamination, the CFU counts for two plant species purchased from one specific trader (viz. H. abyssinica and Acacia xanthophloea) exceeded maximum acceptable contamination limits set by the World Health Organisation (i.e. ≤ 105 to ≤ 107 CFU/g). The levels of contamination varied greatly between the commercially available over the counter product and the plant samples investigated. The microbial types are predominantly opportunistic pathogens. The implementation of good processing practices therefore clearly influences the quality and safety of medicinal products, especially regarding microbial contamination. It is evident that policies and regulations need to be developed and implemented in order to address possible contamination by opportunistic pathogens.  相似文献   

10.
Enumeration of Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus thermophilus is a priority due to their importance in yogurt production. Capillary electrophoresis (CE) of both bacteria could be achieved in 7.2 min with a resolution of 3.2 in the background electrolyte (BGE) containing 4.5 mM Tris(hydroxymethyl) amminomethane (TRIS)–4.5 mM boric acid–0.1 mM ethylenediamine tetraacetate (EDTA) (TBE) buffer (pH 8.4) and 0.05% (v/v) polyethylene oxide (PEO), using a capillary of 47.5 cm (effective length) × 100 μm i.d., injection of 50 mbar × 3 s followed by ?5 kV × 120 s, a voltage and temperature of 20 kV and 25 °C, respectively. Appropriate amounts of PEO in the BGE, sample preparation (i.e. vortex) and introduction were key factors for their separation. A short hydrodynamic injection followed by applying reversed polarity voltage could compress the bacteria into narrow zones, which were detected as separated single peaks. Method linearity (r2 > 0.99), precision (%RSDs < 9.3%), recovery (%R = 91.7–106.7%) and limit of quantitation (1.0 × 106 colony forming unit per mL (CFU/mL)) were satisfactory. Results from the CE analysis of both bacteria in yogurt were not statistically different from those of the plate count method (P > 0.05). The CE method can be used as an alternative for quantitation of L. delbrueckii subsp. bulgaricus and S. thermophilus in yogurt since it was reliable, simple, cost and labor effective and rapid, allowing the analysis of 3 samples/h (comparing to 2d/sample by plate count method).  相似文献   

11.
In this study, Nocardia lactamdurans NRRL 3802 was explored for the first time for production of cephamycin C by using solid-state fermentation. The effects of various substrates, moisture content, inoculum size, initial pH of culture medium, additional nitrogen source and amino acids were investigated for the maximum production of cephamycin C by N. lactamdurans NRRL 3802 in solid-state fermentation. Subsequently, selected fermentation parameters were further optimized by response surface methodology (RSM). The soybean flour as a substrate with moisture content of 65%, initial pH of culture medium of 6.5 and inoculum size of 109 CFU/ml (2 × 108 CFU/gds) at 28 ± 2 °C after 4 days gave maximum production of 15.75 ± 0.27 mg/gds of cephamycin C as compared to 8.37 ± 0.23 mg/gds before optimization. Effect of 1,3-diaminopropane on cephamycin C production was further studied, which further increased the yield to 27.64 ± 0.33 mg/gds.  相似文献   

12.
It was asked whether variations in hemocyte counts in a mussel can be explained by mechanisms known to govern the leukocyte number in vertebrates. Hemolymph of 25 freshly collected Mytilus edulis contained (4.2 ± 1.75) × 106 cells/mL including basophilic and eosinophilic granulocytes and 6.6 ± 5.5% hyalinocytes (15 animals). After 12 or 30 days under optimal laboratory conditions, hemocytes in circulation decreased to less than 1 × 106/mL, the lowest number observed being 5 × 105 cells/mL. Within 2 min of a stressful stimulus, cell numbers doubled or increased by a factor of 3 or 4. After stressing mussels by keeping them out of water for 1 h, cell counts were as high as 1.2 × 107 cells/mL. The quick rate of increase in cell counts is not due to hemocyte proliferation. In mussels, returned to optimal water conditions, cell numbers dropped following an exponential decay curve (y = 5.6865 · (0.9936X). Not all hemocyte types decreased in number to the same extent. After a strong decrease in the total cell count induced by injection of LPS, the remaining hemocyte population contained a larger percentage of basophils. This indicated the disappearance of eosinophilic cells from the circulation. Stress situations caused their return. Hemocytopenia or stress-induced hemocytosis in M. edulis, both in conjunction with changes in the percentage of granulocytes present, resembles margination/demargination processes in mammals where the concentration of circulating leukocyte subsets depends on the expression of adhesive receptor–ligand molecules on the surface of specific leukocyte types and vascular endothelial cells. In Mytilus edulis, variations in the concentration of distinct cell groups excluded heart activity to explain cell fluctuations. Furthermore, in this mussel, where hemocyte proliferation is not the reason for rapid hemocytosis, cell divisions were nevertheless demonstrated; they seem to be important in maintaining hemocyte homeostasis as 10–20% of cells in circulation possess the capacity to proliferate. They belong to the group of basophilic granulocytes.  相似文献   

13.
PurposeThis study aimed to determine whether the SiPM-PET/CT, Discovery MI (DMI) performs better than the PMT-PET/CT system, Discovery 710 (D710).MethodsThe physical performance of both systems was evaluated using NEMA NU 2 standards. Contrast (%), uniformity and image noise (%) are criteria proposed by the Japanese Society of Nuclear Medicine (JSNM) for phantom tests and were determined in images acquired from Hoffman and uniform phantoms using the DMI and D710. Brain and whole-body [18F]FDG images were also acquired from a healthy male using the DMI and D710.ResultsThe spatial resolution at 1.0 cm off-center in the DMI and D710 was 3.91 and 4.52 mm, respectively. The sensitivity of the DMI and D710 was 12.62 and 7.50 cps/kBq, respectively. The observed peak noise-equivalent count rates were 185.6 kcps at 22.5 kBq/mL and 137.0 kcps at 29.0 kBq/mL, and the scatter fractions were 42.1% and 37.9% in the DMI and D710, respectively. The D710 had better contrast recovery and lower background variability. Contrast, uniformity and image noise in the DMI were 61.0%, 0.0225, and 7.85%, respectively. These outcomes were better than those derived from the D710 and satisfied the JSNM criteria. Brain images acquired by the DMI had better grey-to-white matter contrast and lower image noise at the edge of axial field of view.ConclusionsThe DMI offers better sensitivity, performance under conditions of high count rates and image quality than the conventional PMT-PET/CT system, D710.  相似文献   

14.
Francisella tularensis is a highly virulent pathogenic bacterium. In order to identify novel potential antibacterial agents against F. tularensis, libraries of trisubstituted benzimidazoles were screened against F. tularensis LVS strain. In a preliminary screening assay, remarkably, 23 of 2,5,6- and 2,5,7-trisubstituted benzimidazoles showed excellent activity exhibiting greater than 90% growth inhibition at 1 μg/mL. Among those hits, 21 compounds showed MIC90 values in the range of 0.35–48.6 μg/mL after accurate MIC determination. In ex vivo efficacy assays, four of these compounds exhibited 2–3 log reduction in colony forming units (CFU) per mL at concentrations of 10 and 50 μg/mL.  相似文献   

15.
River watersheds in the western part of Turkey (Aegean Sea) are anthropogenically impacted areas, due to the high population density, intensive agricultural and/or industrial activities. The aim of the present survey was to assess the microbiological quality of river waters using indicators of fecal contamination. Five rivers (Meric, Bakircay, Gediz, Kucuk Menderes and Buyuk Menderes) were sampled as seasonally from 2006 to 2008 for fecal coliforms, and fecal streptococci. In order to determine the number of fecal indicator bacteria, membrane filtration method was used. The minimum fecal coliforms and fecal streptococci were counted from the samples taken from the Buyuk Menderes River (5 × 101–3 × 101 CFU/100 ml) especially in the spring and autumn. The highest fecal coliform result was obtained in winters (1.3 × 106 CFU/100 ml) while maximum fecal streptococci value was detected in autumns (6.3 × 104 CFU/100 ml) in the Kucuk Menderes River during 2006–2008. Additionally, the relationships between the fecal indicator bacteria and physico-chemical parameters (temperature, conductivity and pH) were also evaluated, but no significant relationships were observed between the fecal indicator bacteria and environmental parameters. Considering the findings of these studies, it can be said that there is fecal pollution in the rivers reaching the Aegean Sea. The results show that there are a great number of microbial pollution sources in the areas where the river passes through and thus, in order to implement strategies to improve water quality in these rivers, monitoring of these rivers should continue.  相似文献   

16.
There is an increasing interest in the intestinal and immunological effects of probiotics. The aim of the present study is to evaluate the tolerance and beneficial effects in healthy adults of the strain, Lactobacillus salivarius CECT5713 isolated from breast milk. A phase II, randomized, double-blinded, placebo-controlled human clinical trial was carried out in 40 healthy adults. The Probiotic group received a daily dose of 2 × 108 CFU of L. salivarius CECT5713 in capsules during 4 weeks while volunteers of the control received only a placebo. Gastrointestinal and immunological parameters were analyzed. Results showed that L. salivarius CECT5713 was well tolerated and no adverse effects were detected. Consumption of the probiotic strain increased fecal lactobacilli counts (7.9 ± 0.1 vs. 7.05 ± 0.2 CFU/g feces, P = 0.001). Also, an improvement in the frequency of defecation (P = 0.04) was observed. Probiotic treatment induced significantly the percentage of NK cells and monocytes, as well as the plasmatic levels of immunoglobulins M, A and G, and the regulatory cytokine IL-10 (72.3 ± 11.7 in probiotic group vs. 27.3 ± 6.4 pg/mL in control group, P < 0.01). Thus, it can be concluded that daily administration of L. salivarius CECT5713 to healthy adults is safe and improve gut microbiota and different parameters related to immune response.  相似文献   

17.
Monoclonal antibodies (MAbs) against Vibrio vulnificus (isolate I, VVC and isolate II, VVB) were raised using heat-killed and heat-killed plus SDS–mercaptoethanol treated forms of VVC and VVB for immunizing Swiss mice. Twenty three hybridomas producing MAbs against V. vulnificus were selected and divided into five groups according to their specificities to different V. vulnificus isolates and apparent protein antigens which ranged from ∼ 3–50 kDa. Four groups were specific to V. vulnificus without cross reactivity to either other Vibrio spp. or other bacterial species. In dot blot based assays, one group of MAbs were specific to VVC, with a sensitivity of ∼ 1.6 × 107 CFU ml 1 (∼ 1.6 × 104 cells spot 1), and bound to proteins of ∼ 50 and ∼ 39 kDa. Other MAbs, binding to proteins ranging from ∼ 3–14 and ∼ 40 kDa, detected VVB (but not VVC) with high sensitivity at ∼ 1.6 × 105 and 4 × 106 CFU ml 1 (∼ 1.6 × 102 and 4 × 103 cells spot 1), respectively. In addition, certain MAbs were able to recognize V. vulnificus in tissues by means of immunohistochemistry. The remaining groups demonstrated cross reactivity to Vibrio fluvialis. MAbs from this study can, therefore, detect the difference between some isolates of V. vulnificus and in addition to pathogen detection may, with further antibodies, form the basis of serovar typing isolates in the future.  相似文献   

18.
Due to the cytotoxic effect of antimicrobial peptides (AMP) against several microorganism and tumor cells has been proposed their association with the immune system. However, just a few reports have shown this relationship. In this study, mice were treated with gomesin, a β-hairpin AMP that exhibit high cytotoxicity against bacterial and tumor cells. Different effects in the immune system were observed, such as, decrease of CD3+ in T lymphocytes (Control: 17.7 ± 1.4%; Gomesin: 7.67 ± 1.2%) and in hematopoietic progenitors and increase of hematopoietic stem cell (Control: 0.046 ± 0.004%; Gomesin: 0.067 ± 0.003%), B220+ B lymphocytes (Control: 38.63 ± 1.5%; Gomesin: 47.83 ± 0.48%), and Mac-1+F4/80+ macrophages (Control: 11.76 ± 3.4%; Gomesin: 27.13 ± 4.0%). Additionally, macrophage increase was accompanied by an increase of macrophage phagocytosis (Control 20.85 ± 1.53; Gomesin 31.32 ± 1 Geometric mean), interleukin 6 (Control: 47.24 ± 1.9 ng/mL; Gomesin: 138.68 ± 33.68 ng/mL) and monocyte chemoattractant protein-1 (Control: 0.872 ± 0.093 ng/mL; Gomesin: 1.83 ± 0.067 ng/mL). Thus, this report showed immunomodulatory activity of gomesin in the immune system of mice.  相似文献   

19.
The gelatinase members of the MMP family have consistently been associated with tumor invasiveness, which make them an attractive target for molecular imaging. We report new activatable proteolytic optical imaging agents that consist of triple-helical peptide (THP) conjugates, with high specificity to the gelatinases, bearing quenched cypate dyes. With quenching efficiencies up to 51%, the amplified fluorescence signal upon cypate3-THP hydrolysis by the gelatinases (kcat/KM values of 6.4 × 103 M−1 s−1 to 9.1 × 103 M−1 s−1 for MMP-2 and MMP-9, respectively) in mice bearing human fibrosarcoma xenografted tumors was monitored with fluorescence molecular tomography. There was significant fluorescence enhancement within the tumor and this enhancement was reduced by treatment with pan-MMP inhibitor, Ilomastat. These data, combined with the gelatinase substrate specificity observed in vitro, indicated the observed fluorescence at the site of the tumor was due to gelatinase mediated hydrolysis of cypate3-THP.  相似文献   

20.
《Endocrine practice》2014,20(3):236-243
ObjectiveTo assess whether 25-hydroxyvitamin D (25[OH]D) deficiency is a risk factor for chronic kidney disease (CKD) in ambulatory indigent patients.MethodsData for all serum 25(OH)D concentrations measured during 2010 in our ambulatory nondialysis-dependent patients were analyzed along with CKD-related parameters. Patients were stratified into groups based on 25(OH)D levels of < 10, 10 to 19, 20 to 29, and ≥ 30 ng/mL. CKD was defined by estimated glomerular filtration rate (eGFR; Chronic Kidney Disease-Epidemiology Collaboration [CKD-EPI] equation) and abnormal urine protein to creatinine ratios. CKD-associated parameters included serum parathyroid hormone (PTH), 1,25-dihydroxyvitamin D (1,25[OH]2D), alkaline phosphatase, albumin, corrected calcium, and total CO2 levels.ResultsA total of 2,811 patients had 25(OH)D levels measured. Patients with 25(OH)D levels < 10 ng/mL had significantly increased relative risk (RR) of an eGFR < 15 mL/min/1.73 m2 (RR, 4.0), an eGFR of 15 to 29 mL/min/1.73 m2 (RR, 2.6), urine protein to creatinine ratio > 3.5 g/g (RR, 5.6), and serum PTH > 100 pg/mL (RR, 2.8) compared to patients with a 25(OH)D level ≥ 30 ng/mL. Patients with 25(OH)D levels of 10 to19 ng/mL had significantly increased RR of a urine protein to creatinine ratio > 3.5 g/g (RR,4.8) and serum PTH > 100 pg/mL (RR, 1.5) compared to patients with 25(OH)D levels ≥ 30 ng/mL.Conclusion25(OH)D deficiency (< 10 ng/mL) was associated with reduced eGFR, nephrotic-range proteinuria, and increased PTH levels in our population of ambulatory urban indigent patients. (Endocr Pract. 2014;20:236-243)  相似文献   

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