Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound

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Query: EC:3.4.23.5 (cathepsin D)
4,130 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Breast cancer cells oversecrete the lysosomal peptidase cathepsin D as a pro-enzyme. In this study, we assessed the effect of media conditioned by MRC-5 fibroblasts or MCF-7/6 breast cancer cells on cathepsin D (CD) production and secretion by these two cell types. We also considered the influence of estrogens and matrix components (type I or type IV collagen, or Matrigel) on the expression and activity of CD produced by breast cancer cells of different invasive potentials (MCF-7/AZ, MCF-7/6, MDA-MB-231). In our system, fibroblasts conditioned medium does not significantly affect CD levels produced and secreted by the MCF-7/6 cells. However, we found that fibroblasts are able to capture the pro-CD secreted by these tumor cells by a mannose 6-phosphate-dependent process. We also found a positive correlation between the proportion of extracellular CD levels and the invasive potentials of the tumor cell types considered. If estrogens are able to upregulate CD production and secretion by receptor-positive cells, it is not the case of extracellular matrix components. On the other hand, our results indicate that matrix components are able to influence the distribution of the different CD forms in and out of the cells. Our data suggest that tumor fibroblasts, by enhancing their intracellular CD levels, could assist cancer cells in the digestion of extracellular matrix during the invasion of tissues.
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PMID:Fibroblasts capture cathepsin D secreted by breast cancer cells: possible role in the regulation of the invasive process. 1189 22

Effects of patented mixtures of substances, used as drilling fluids in petroleum industry, on the activity of enzymes (cathepsin D, EC 3.4.23.5; catalase, EC 1.11.1.6; and DNase, EC 3.1.4.6) and the content of analytes (malondialdehyde, fatty acids, free and collagen-associated hydroxyproline, bile acids, and total protein) in liver, gills, muscles, gonads, and bile have been studied under aquarium conditions in mature river flounder and one-year-old salmon for the purpose of determining maximum permissible concentrations. Measuring 25-30 independent biochemical parameters per organ is sufficient for establishing a direct relationship between the concentration of an industrial toxicant and the integral biochemical index, a new characteristic defined as the ratio of the number of biochemical parameters significantly deviating from control values to the total number of the parameters measured.
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PMID:[Determination of maximum permissible concentrations of industrial toxicants using the integral biochemical index]. 1206 91

Interactions of stromal and tumor cells with the extracellular matrix may regulate expression of proteases including the lysosomal proteases cathepsins B and D. In the present study, we determined whether the expression of these two proteases in human breast fibroblasts was modulated by interactions with the extracellular matrix component, collagen I. Breast fibroblasts were isolated from non-malignant breast tissue as well as from tissue surrounding malignant human breast tumors. Growth of these fibroblasts on collagen I gels affected cell morphology, but not the intracellular localization of vesicles staining for cathepsin B or D. Cathepsins B and D levels (mRNA or intracellular protein) were not affected in fibroblasts growing on collagen I gels or plastic, nor was cathepsin D secreted from these cells. In contrast, protein expression and secretion of cathepsin B, primarily procathepsin B, was induced by growth on collagen I gels. The induced secretion appeared to be mediated by integrins binding to collagen I, as inhibitory antibodies against alpha(1), alpha(2), and beta(1) integrin subunits prevented procathepsin B secretion from fibroblasts grown on collagen. In addition, procathepsin B secretion was induced when cells were plated on beta(1) integrin antibodies. To our knowledge, this is the first examination of cathepsin B and D expression and localization in human breast fibroblasts and their regulation by a matrix protein. Secretion of the cysteine protease procathepsin B from breast fibroblasts may have physiological and pathological consequences, as proteases are required for normal development and for lactation of the mammary gland, yet can also initiate and accelerate the progression of breast cancer.
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PMID:Interaction of human breast fibroblasts with collagen I increases secretion of procathepsin B. 1207 42

Lysosomal serine and cysteine proteases are reported to play a role in collagen degradation. In this study, the activities of the lysosomal cysteine proteases cathepsin B and H, dipeptidyl peptidase I, and the serine protease tripeptidyl peptidase I and dipeptidyl peptidase II, all ascribed a role in collagen digestion, were compared with those of the aspartate protease cathepsin D, and lysosomal glycosidases in leukocytes from rheumatoid arthritis patients at different stages of the disease. In all patients the activities of cysteine protease cathepsin B, dipeptidyl peptidase I, aspartate protease cathepsin D, and two glycosidases were elevated, but the activities of the serine proteases tripeptidyl peptidase I, dipeptidyl peptidase II, and the cysteine protease cathepsin H was unchanged. The magnitude of the increased activity was correlated with the duration of the disease. Patients with long-standing RA (10 years or more) had higher cysteine protease activity in their leukocytes than did those with disease of shorter duration. This tendency suggests that elevated lysosomal cysteine protease activities, together with aspartate protease cathepsin D and lysosomal glycosidases (but not serine proteases), are associated with progression of rheumatoid arthritis.
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PMID:Lysosomal peptidases and glycosidases in rheumatoid arthritis. 1210 54

Current topics are presented on four urinary proteins under investigations with special emphasis on importance of preanalytical sampling and assay standardization. These comprise of albumin, protein 1 (P1), beta 2-microglobulin (beta 2-m), and Type IV collagen. Microalbuminuria is an essential marker for early diabetic nephropathy. The author is trying to reduce the discrepancy of urinary albumin value with value assignment from CRM470, BCR international reference material, to calibrator in each assay system. At the same time nonspecific binding of the protein on urine containers were found, which can cause the discrepancy. Furthermore structure of albumin both in calibrator and urine is important. Protein 1 is a low molecular weight nonglycoprotein of 14 kDa isolated from pathologic urine. Marked sex-related difference was noted in urine, being higher in male than female. This is due to the contamination from prostate. Its localization was finally demonstrated with immunohistochemical staining and a RT-PCR method. With the same methods the protein is demonstrated to be synthesized in female prostate. beta 2-m is easily degraded in acid urine. Employing various immunochemical methods and analyses of its amino acid sequences, we successfully identified cathepsin D as one of acid proteases responsible for the degradation. Urinary measurement of type IV collagen is now clinically under use for an independent marker for early diabetic nephropathy. Nonspecific elevation was observed in urine with UTI, in which mechanisms is should be clarified.
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PMID:[Current topics on urinary proteins: human albumin, protein 1, beta 2-microglobulin, and type IV collagen]. 1216 72

The immunohistochemical expression of the extracellular matrix (ECM) components tenascin (TN), fibronectin (FN), collagen type IV (Coll) and laminin (LN), and their possible relationships were studied in a series of 134 operable breast cancer cases. Their expression was also compared with the expression of the proteolytic enzyme cathepsin D (CD), the adhesion molecule CD44 standard form (CD44s) and other known factors to clarify the prognostic value and role of these molecules in tumour progression and metastasis. TN expression in the tumour stroma was positively correlated with tumour grade and size, CD44s expression, tumour and stromal CD expression as well as with FN, laminin and Coll expression in the same areas. TN expression was inverse correlated with ER status. Its expression at the invasion front was only positively correlated with the lymph node status. Survival analysis showed an increased mortality risk associated with high levels of TN expression. In multivariate analysis, among the ECM proteins, only TN expression was independently correlated with patients' survival. FN expression was positively correlated with lymph node involvement, with the proliferation-associated index Ki-67 and stromal CD expression. Survival analysis showed an increased mortality risk associated with a high level of FN expression. Coll expression was positively correlated with the tumour size and LN expression. An inverse relationship of Coll expression with ER and PgR receptor status was also found. LN expression was positively correlated with tumour and stromal CD expression, with the proliferation-associated index Ki-67 and inversely with ER receptor status. The observed alterations in the expression of ECM proteins in breast cancer tissue and their correlations with the proteolytic enzyme CD and the adhesion molecule CD44s, suggest an involvement in cancer progression. In addition, overexpression of stromal TN and FN seems to have negative prognostic value in breast cancer patients.
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PMID:Immunohistochemical expression of extracellular matrix components tenascin, fibronectin, collagen type IV and laminin in breast cancer: their prognostic value and role in tumour invasion and progression. 1246 Jul 79

Talc ore may contain several other minerals including calcite, dolomite, magnesite, tremolite, anthophyllite, antigorite, quartz, pyrophyllite, micas, or chlorites. Talc products are sold in a multitude of grades which have physical or functional characteristics especially suited for particular applications, so occupational and consumer exposures to talc are complex. Epidemiology studies have suggested an association between non-fibrous talc and lung cancer risk. Talc was nominated by the National Institute of Occupational Safety and Health (NIOSH) for study by the NTP because of widespread human exposure and because of the lack of adequate information on its chronic toxicity and potential carcinogenicity. Toxicology and carcinogenicity studies of talc (non-asbestiform, cosmetic grade), a finely powdered hydrous magnesium silicate, were conducted by exposing groups of F344/N rats to aerosols for 6 hours per day, 5 days per week for up to 113 weeks (males) or 122 weeks (females). Groups of B6C3F1 mice were exposed similarly for up to 104 weeks. LIFETIME STUDY IN RATS: Groups of 49 or 50 male and 50 female rats were exposed to aerosols of 0, 6, or 18 mg/m(3) talc until mortality in any exposure group reached 80% (113 weeks for males and 122 weeks for females). These exposures were selected based on 4-week inhalation studies of the terminal lung talc burden in F344/N rats; concentrations greater than 18 mg/m(3) were expected to overwhelm lung clearance mechanisms and impair lung function. These exposure concentrations provided a dose equivalent of 0, 2.8, or 8.4 mg/kg per day for male rats and 0, 3.2, or 9.6 mg/kg per day for female rats. In a special study, additional groups of 22 male and 22 female rats were similarly exposed and examined for interim pathology evaluations or pulmonary function tests after 6, 11, 18, and 24 months and lung biochemistry and cytology studies after 24 months. The talc aerosols had a median mass aerodynamic diameter of 2.7 mm in the 6 mg/m(3) chamber and a median diameter of 3.2 mm in the 18 mg/m(3) chamber, with geometric standard deviations of 1.9 mm. However, there was a 7-week period beginning at study week 11 during which the chamber concentration for the 18 mg/m(3) rats varied from approximately 30 to 40 mg/m(3) because of difficulties with the aerosol concentration monitoring system. Further, there was a 12-week period beginning at approximately week 70 during which there were difficulties in generating the talc aerosol, and the chamber concentrations for rats and mice were substantially lower than the target concentrations. Survival, Body Weights, and Clinical Findings: The survival of male and female rats exposed to talc was similar to that of the controls. Mean body weights of rats exposed to 18 mg/m(3) were slightly lower than those of controls after week 65. No clinical findings were attributed to talc exposure. Pathology Findings: Absolute and relative lung weights of male rats exposed to 18 mg/m(3) were significantly greater than those of controls at the 6-, 11-, and 18-month interim evaluations and at the end of the lifetime study, while those of female rats exposed to 18 mg/m(3) were significantly greater at the 11-, 18-, and 24-month interim evaluations and at the end of the lifetime study. Inhalation exposure of rats to talc produced a spectrum of inflammatory, reparative, and proliferative processes in the lungs. Granulomatous inflammation occurred in nearly all exposed rats and the severity increased with exposure duration and concentration. Hyperplasia of the alveolar epithelium and interstitial fibrosis occurred in or near foci of inflammation in many exposed rats, while squamous metaplasia of the alveolar epithelium and squamous cysts were also occasionally seen. Accumulations of macrophages (histiocytes), most containing talc particles, were found in the peribronchial lymphoid tissue of the lung and in the bronchial and mediastinal Iymph nodes. In female rats, the incidences of alveolar/bronchiolar adenoma, carcinoma, and adenoma or carcinoma (combined) in the 18 mg/m(8 mg/m(3) group were significantly greater than those of controls. The incidences of pulmonary neoplasms in exposed male rats were similar to those in controls. Minor alterations attributed to talc exposure were also observed in the upper respiratory tract. Hyperplasia of the respiratory epithelium of the nasal mucosa in males and accumulation of cytoplasmic, eosinophilic droplets in the nasal mucosal epithelium in male and female rats occurred with a concentration-related increased incidence in the exposed groups. Adrenal medulla pheochromocytomas [benign, malignant, or complex (combined)] occurred with a significant positive trend in male and female rats, and the incidences in the 18 mg/m(3) groups were significantly greater than those of controls. Although adrenal medulla hyperplasia occurred with similar frequency among exposed and control females, the incidences of hyperplasia in exposed males were significantly lower than in controls. Lung Talc Burden: Lung talc burdens of male and female rats exposed to 6 mg/m(3) were similar and increased progressively from 6 to 24 months. Lung talc burdens of females exposed to 18 mg/m(3) also increased progressively from 6 to 24 months, while those of males exposed to 18 mg/m(3) remained about the same after 18 months. Lung burdens were generally proportional to exposure concentration at each interim evaluation. Pulmonary Function, Bronchoalveolar Lavage, and Lung Biochemistry: In exposed male and female rats there was a concentration-related impairment of respiratory function which increased in severity with increasing exposure duration. The impairment was characterized by reductions in lung volume (total lung capacity, vital capacity, and forced vital capacity), lung compliance, gas exchange efficiency (carbon monoxide diffusing capacity), and nonuniform intrapulmonary gas distribution. After 24 months, males exposed to 6 mg/m(3) talc had a significant increase in beta-glucuronidase and polymorphonuclear leukocytes; males exposed 18 mg/m(3) had significant increases in b -glucuronidase, lactate dehydrogenase, alkaline phosphatase, and total protein in bronchoalveolar lavage fluid. All exposed females had significantly increased a-glucuronidase, lactate dehydrogenase, alkaline phosphatase, total protein, and polymorphonuclear leukocytes; 18 mg/m(3) females also had significantly increased glutathione reductase. Viability and phagocytic activity of macrophages recovered from lavage fluid were not affected by talc exposure. Total lung collagen was significantly increased in rats at both exposure concentrations after 24 months, while collagenous peptides in lavage fluid and the percentages of newly synthesized protein from females, but not males, were also significantly increased at the 6 or 18 mg/m(3) levels. In addition, lung proteinase activity, primarily cathepsin D-like activity, was significantly greater in exposed males and females. Rats exposed to talc also had significant increases in collagenous peptides and acid proteinase in lung homogenates. 2-YEAR STUDY IN MICE: Groups of 47 to 49 male and 48 to 50 female mice were exposed to aerosols containing 0, 6, or 18 mg/m(3) talc for up to 104 weeks. These exposures were selected based on 4-week inhalation studies of the terminal lung talc burden in B6C3F1 mice; concentrations greater than 18 mg/m(3) were expected to overwhelm lung clearance mechanisms and impair lung function. These exposure concentrations provide a dose equivalent of 0, 2, or 6 mg/kg per day for male mice and 0, 1.3, or 3.9 mg/kg per day for female mice. In a special study, additional groups of 39 or 40 male and 39 or 40 female mice similarly exposed were examined for interim pathology evaluations, lung biochemistry, and cytology studies after 6, 12, and 18 months of exposure. The talc aerosols had a median mass aerodynamic diameter of 3.3 mm with a geometric standard deviation of 1.9 mm in the 6 mg/m(3) chamber, and a median diameter of 3.6 mm with a geometric standard deviation of 2.0 mm in the 18 mg/m(3) chamber. Further, there was a 12-week period beginning at approximately week 70 during which there were difficulties in generating the talc aerosol, and the chamber concentrations for rats and mice were substantially lower than the target concentrations. Survival, Body Weights, and Clinical Findings: Survival and final mean body weights of male and female mice exposed to talc were similar to those of the controls. There were no clinical findings attributed to talc exposure. Pathology Findings: Inhalation exposure of mice to talc was associated with chronic active inflammation and the accumulation of macrophages in the lung. In contrast to rats, hyperplasia of the alveolar epithelium, squamous metaplasia, or interstitial fibrosis were not associated with the inflammatory response in mice, and the incidences of pulmonary neoplasms in exposed and control groups of mice were similar. Accumulations of macrophages (histiocytes) containing talc particles were also present in the bronchial Iymph node. In the upper respiratory tract, cytoplasmic alteration, consisting of the accumulation of cytoplasmic eosinophilic droplets in the nasal mucosal epithelium, occurred with a concentration-related increased incidence in exposed male and female mice. Lung Talc Burden: Lung talc burdens of mice exposed to 6 mg/m(3) were similar between males and females and increased progressively from 6 to 24 months, except for males at 18 months. The lung talc burdens of mice exposed to 18 mg/m(3) were also similar between the sexes at each interim evaluation. Although the talc burdens of males and females increased substantially from 6 to 24 months, the values at 12 and 18 months were similar. Generally, lung burdens of mice exposed to 18 mg/m(3) were disproportionately greater than those of mice exposed to 6 mg/m(3), suggesting that clearance of talc from the lung was impaired, or impaired to a greater extent, in mice exposed to 18 mg/m(3) than in mice exposed to 6 mg/m(3). Bronchoalveolar Lavage and Lung Biochemistry: Increases in total protein, beta-glucuronidase, lactate dehydrogenase, glutathione reductase, total nucleated cells, and polymorphonuclear leukocytes in bronchoalveolar lavage fluid were observed primarily in mice exposed to 18 mg/m(3), although some parameters were also increased in mice exposed to 6 mg/m(3). The amount of collagenous peptides in lavage fluid and total lung collagen were increased in male and female mice exposed to 18 mg/m(3). Acid proteinase activity, principally cathepsin D-like activity, of lung homogenate supernatant fluid was also significantly increased in mice at the 18 mg/m(3) exposure concentration. CONCLUSIONS: Under the conditions of these inhalation studies, there was some evidence of carcinogenic activity of talc in male F344/N rats based on an increased incidence of benign or malignant pheochromocytomas of the adrenal gland. There was clear evidence of carcinogenic activity of talc in female F344/N rats based on increased incidences of alveolar/bronchiolar adenomas and carcinomas of the lung and benign or malignant pheochromocytomas of the adrenal gland. There was no evidence of carcinogenic activity of talc in male or female B6C3F1 mice exposed to 6 or 18 mg/m(3). The principal toxic lesions associated with inhalation exposure to the same concentrations of talc in rats included chronic granulomatous inflammation, alveolar epithelial hyperplasia, squamous metaplasia and squamous cysts, and interstitial fibrosis of the lung. These lesions were accompanied by impaired pulmonary function characterized primarily by reduced lung volumes, reduced dynamic and/or quasistatic lung compliance, reduced gas exchange efficiency, and nonuniform intrapulmonary gas distribution. In mice, inhalation exposure to talc produced chronic inflammation of the lung with the accumulation of alveolar macrophages. Synonyms: talcum; agalite; emtal 596; non-asbestiform talc; non-fibrous talc; steatite; hydrous magnesium silicate
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PMID:NTP Toxicology and Carcinogenesis Studies of Talc (CAS No. 14807-96-6)(Non-Asbestiform) in F344/N Rats and B6C3F1 Mice (Inhalation Studies). 1261 90

Cartilage stiffness was measured ex vivo at the micrometer and nanometer scales to explore structure-mechanical property relationships at smaller scales than has been done previously. A method was developed to measure the dynamic elastic modulus, |E(*)|, in compression by indentation-type atomic force microscopy (IT AFM). Spherical indenter tips (radius = approximately 2.5 microm) and sharp pyramidal tips (radius = approximately 20 nm) were employed to probe micrometer-scale and nanometer-scale response, respectively. |E(*)| values were obtained at 3 Hz from 1024 unloading response curves recorded at a given location on subsurface cartilage from porcine femoral condyles. With the microsphere tips, the average modulus was approximately 2.6 MPa, in agreement with available millimeter-scale data, whereas with the sharp pyramidal tips, it was typically 100-fold lower. In contrast to cartilage, measurements made on agarose gels, a much more molecularly amorphous biomaterial, resulted in the same average modulus for both indentation tips. From results of AFM imaging of cartilage, the micrometer-scale spherical tips resolved no fine structure except some chondrocytes, whereas the nanometer-scale pyramidal tips resolved individual collagen fibers and their 67-nm axial repeat distance. These results suggest that the spherical AFM tip is large enough to measure the aggregate dynamic elastic modulus of cartilage, whereas the sharp AFM tip depicts the elastic properties of its fine structure. Additional measurements of cartilage stiffness following enzyme action revealed that elastase digestion of the collagen moiety lowered the modulus at the micrometer scale. In contrast, digestion of the proteoglycans moiety by cathepsin D had little effect on |E(*)| at the micrometer scale, but yielded a clear stiffening at the nanometer scale. Thus, cartilage compressive stiffness is different at the nanometer scale compared to the overall structural stiffness measured at the micrometer and larger scales because of the fine nanometer-scale structure, and enzyme-induced structural changes can affect this scale-dependent stiffness differently.
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PMID:Dynamic elastic modulus of porcine articular cartilage determined at two different levels of tissue organization by indentation-type atomic force microscopy. 1511 40

Cancer invasion and metastasis develop through a sequence of processes involving loss of cell-cell and cell-matrix adhesions, proteolysis and induction of angiogenesis. We reviewed the current literature on the molecules that have been shown to play a significant role in these three steps of metastatisation in bladder cancer (BC) cells and their host microenvironment. Particular emphasis was given to markers that are assessable through immunohistochemistry and for which an additional prognostic value over the TNM variables has been recognized, in order to identify a subset of tumour markers readily available for application in daily clinical practice. We conclude that markers such as E-cadherin, Sialosyl-LeX, laminin, collagen IV, TSP-1 and MVD are useful prognostic markers, alpha, beta, and gamma catenin, MMP-2 and -9, uPAR, PD-ECGF and Bfgf can be considered potentially useful, while research on CD44, MMP-1 and -3, uPA, cathepsin D and VEGF has proved inconclusive. Further research in this field should concentrate on the molecules listed in the first group.
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PMID:Metastasis markers in bladder cancer: a review of the literature and clinical considerations. 1530 99

The early interface reaction of cancellous bone to a nanocrystalline hydroxyapatite (HA) cement containing 3 wt% collagen type I (HA/Coll) with a setting under physiological temperature and pH was observed using immunohistochemical techniques. Pure HA served as a control. Cylinders with a diameter of 2 mm were implanted into the proximal tibia of 72 adult Wistar rats. Histological sections of 6 animals were prepared after 1, 2, 4, 6, 14 and 28 days. First, osteoblast-like cells as well as a marked reaction for osteonectin, osteopontin and its ligand CD44 were observed as early as 2 days after implantation at the interface around HA/Coll implants. Further, reactivity for ED1 and cathepsin D, both markers for phagocytotic cells, appeared earlier and stronger around HA/Coll. In cell counts, a significantly higher average number of ED1- and cathepsin D-positive phagocytotic cells was observed around the HA/Coll implants on days 6 (p < 0.01), 14 and 28 (p < 0.05). The number of osteopontin-positive cells was significantly higher around HA/Coll implants at days 6 and 14 (p < 0.05). Two weeks after the implantation, first islands of newly formed woven bone were observed around the HA/Coll implant, but not around the control implant. The amount of direct bone contact after 28 days averaged 28% around pure HA and 51% around HA/Coll implants (p < 0.05). While both implants displayed a good osteoconductivity, a higher bone remodelling activity was observed around collagen-containing HA implants compared to pure HA implants. It appears that the addition of collagen to HA implants can enhance both phagocytotic and osteogenic processes. This may result in an earlier acceptance and better osseointegration of the HA/Coll implants into the surrounding tissue.
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PMID:Collagen type I increases bone remodelling around hydroxyapatite implants in the rat tibia. 1565 32


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