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PubMed2004

Structure of liquid and glassy methanol confined in cylindrical pores.

We present a neutron scattering analysis of the density and the static structure factor of confined methanol at various temperatures. Confinement is performed in the cylindrical pores of MCM-41 silicates with pore diameters D=24 and 35 A. A change of the thermal expansivity of confined methanol at low temperature is the signature of a glass transition, which occurs at higher temperature for the smallest pore. This is evidence of a surface induced slowing down of the dynamics of the fluid. The structure factor presents a systematic evolution with the pore diameter, which has been analyzed in terms of excluded volume effects and fluid-matrix cross correlation. Conversely to the case of Van der Waals fluids, it shows that stronger fluid-matrix correlations must be invoked most probably in relation with the H-bonding character of both methanol and silicate surface.

Journal Article↗
PubMed1993

Extracellular matrix modifications in rat tissues of different ages. Correlations between elastin and collagen type I mRNA expression and lysyl-oxidase activity.

We used a rat model to correlate age, matrix gene expression and lysyl oxidase activity in three connective tissues, skin, aorta and lung. By in situ hybridization, we showed that intense collagen type I and elastin mRNA expression were limited to a brief postnatal period. Although there were some organ-specific differences, the mRNA abundance for these two scleroproteins drastically diminished with time. Thus, the majority of mesenchymal cells in young (60 days) and old (720 days) animals, appeared to be in a quiescent state, consistent with the slow turnover of these two scleroproteins. We also measured the activity of lysyl oxidase, an enzyme which plays a crucial role in the formation of crosslinks in both procollagen and tropoelastin molecules. In all the organs investigated, we observed a tissue-dependent pattern of activity. Moreover in this study we focused on the importance of gene matrix expression in evaluating lysyl oxidase activity of aging tissues.

Aging↗
PubMed2000

Matrix metalloproteinases in human gliomas: activation of matrix metalloproteinase-2 (MMP-2) may be correlated with membrane-type-1 matrix metalloproteinase (MT1-MMP) expression.

To evaluate possible roles of matrix metalloproteinase (MMP)-1, -2, tissue inhibitor of metalloproteinase (TIMP)-1, -2 and membrane-type-1 matrix metalloproteinase (MT1-MMP) in invasion of human gliomas, expressions of these proteins were investigated in ten cases of human glioma and two meningioma tissues and eight human glioma cell lines. In gelatin zymography, MMP-2 activities of glioblastomas were higher than astrocytomas. The activated form of MMP-2 was seen in five of six cases of glioblastomas, but not in astrocytomas. MMP-9 activity was detected in all cases of malignant astrocytomas but the reactivity of MMP-9 was weaker than that of MMP-2. MT1-MMP mRNA expression in glioblastomas was higher than that in astrocytomas. Five cases of glioblastomas with activated form of MMP-2 had MT1-MMP expressions. In vitro, human glioma cell lines with high expression of MT1-MMP also showed high MMP-2 activity. TIMP-1 transcripts were constitutively present in almost all glioma tissues and cell lines, whereas TIMP-2 mRNA were weak especially in malignant gliomas. Imbalance of TIMP-2/MMP-2 was observed using immunoprecipitation analysis in a glioma cell line. High expression of MMP-2 and MT1-MMP is possibly involved in invasiveness of malignant glioma.

Animals↗
PubMed1975

Reovirus antibody patterns in dogs: a trial for the application of principal component analysis to seroepidemiology.

In 100 dogs in Morioka and its vicinity serologically surveyed for reovirus infection, there were significant correlations between hemagglutination-inhibiting and neutralizing antibody titers of the same virus types. In order to establish a proper index for the evaluation of infection, principal component analysis was applied to the analysis of data, including standard immune sera. Of nine samples of matrix examined, correlation matrix of 6 variables was suggested to afford the most proper result. Essential information from the original data was accounted for by factor loadings of the first 3 components. The 6 attributes of serum antibody were classified into three groups. In a scatter diagram serum samples were classified also into three major groups corresponding to the three reovirus types, and the serotypic pattern of infection was clearly visualized.

Animals↗
PubMed2006

Serum matrix metalloproteinase-3 levels correlate with disease activity in relapsing-remitting multiple sclerosis.

BACKGROUND: Adhesion molecules and matrix metalloproteinases (MMPs) are known to be relevant to the ongoing development and disappearance of areas of demyelination in the white matter of the CNS of multiple sclerosis (MS) patients. This study examined whether serum matrix metalloproteinase-3 (MMP-3) levels correlate with disease activity in MS. METHODS: Serum MMP-3 levels in 47 consecutive patients with relapsing-remitting MS were measured by immunoassay every 4 weeks over a 15 month period. RESULTS: During the study period, 48 clinical relapses occurred. Serum MMP-3 levels within 1 month of relapse were significantly higher than during the remission phase. Sequential analysis showed that serum MMP-3 levels had increased transiently at the time of clinical relapse but returned to the normal range within a month. CONCLUSIONS: Circulatory MMP-3 levels are correlated with disease activity in relapsing-remitting MS. This may contribute to the breakdown of the blood-brain barrier at the time of relapse.

Adult↗
PubMed2001

Activation of matrix metalloproteinase-2 is correlated with invasiveness in thymic epithelial tumors.

UNLABELLED: BACKGROUND AND OBJECTS: Matrix degradation, which is a critical event in the process of tumor invasion and metastasis, is considered to be caused by the action of proteolytic enzymes. METHODS: We examined the gelatinolytic activity of matrix metalloproteinase (MMP)-9, and the activity of active and inactive forms of MMP-2 in five thymi, five noninvasive thymomas, eight invasive thymomas, and five thymic carcinomas by quantitative gelatinolytic zymography. RESULTS: The gelatinolytic activity of active MMP-2 in five thymi was zero. The mean gelatinolytic activity of active MMP-2 was 0.020 +/- 0.015 in noninvasive thymoma, 0.084 +/- 0.098 in invasive thymoma and 0.246 +/- 0.194 in thymic carcinoma. The gelatinolytic activity of active MMP-2 correlated with the invasiveness of thymic epithelial tumors (Spearman rank correlation: r-value = 0.532). The gelatinolytic activity of active MMP-2 in three thymoma cases with microscopic capsular invasion was the same as that of noninvasive thymoma. When thymoma cases showing microscopic capsular invasion were classified into the "macroscopically noninvasive thymoma" group, the gelatinolytic activity of active MMP-2 correlated with the invasiveness of thymic epithelial tumors (Spearman rank correlation: r-value = 0.621). CONCLUSIONS: The gelatinolytic activity of active MMP-2 significantly correlated with the invasiveness in thymic epithelial tumors. J. Surg. Oncol. 2001;76:169-175.

Enzyme Activation↗
PubMed2000

Renin-angiotensin system gene expression in post-transplant hypertension predicts allograft function.

BACKGROUND: Registry analyses and single-center studies have demonstrated that hypertension significantly increases the risk for chronic graft loss. The graft itself may contribute to posttransplant hypertension, and intragraft vasoactive hormones therefore, may be dysregulated in posttransplant hypertension. METHODS: We used the reverse-transcription polymerase chain reaction to assess the intragraft regulation of renin-angiotensin system transcripts in biopsy samples from 42 stable renal transplant patients with posttransplant hypertension. We also examined mRNA expression of inducible nitric oxide synthase, transforming growth factor-beta (TGF-beta), select cytokines, and metalloproteinase transcripts in biopsy tissue. Polymerase chain reaction products were quantitated using high performance liquid chromatography and normalized to beta-actin mRNA expression. Serum creatinine, glomerular filtration rate or creatinine clearance and tubular atrophy on biopsy were concurrently assessed. RESULTS: Renin and select Thl cytokine mRNA expression correlated with blood pressure. Type 1 angiotensin II receptor mRNA expression significantly correlated with glomerular filtration rate or creatinine clearance (P = 0.034) and inversely correlated with Th1 cytokines, inducible nitric oxide synthase, and cyclooxygenase-1 mRNA expression (P< or =0.013 for each). Type 1 angiotensin II receptor mRNA also approached a significant inverse correlation with TGF-beta mRNA expression (P = 0.09). Conversely, angiotensin-converting enzyme mRNA expression directly correlated with Thl cytokine (P< or =0.008 for each) and TGF-beta mRNA expression (P = 0.006). Type 1 angiotensin II receptor mRNA expression also correlated with matrix metalloproteinase-1 promoter region, tissue inhibitor of matrix metalloproteinase-2 (TIMP-2) and tissue inhibitor of matrix metalloproteinase-3 mRNA expression. Notably, matrix metalloproteinase-1 promoter region, tissue inhibitor of matrix metalloproteinase-2, and tissue inhibitor of matrix metalloproteinase-3 inversely correlated with TGF-beta mRNA expression (P< or =0.0027 for each). Type 1 angiotensin II receptor mRNA expression at biopsy directly correlated with glomerular filtration rate at 2 year's follow-up. However, angiotensin-converting enzyme mRNA expression at biopsy inversely correlated with glomerular filtration rate at 2 year's follow-up. CONCLUSIONS: These data suggest that allograft-level RAS gene expression may be predictive of future graft function in the setting of diastolic hypertension.

Adult↗
PubMedDate not supplied

Low attenuation intratumoral matrix: CT and pathologic correlation.

Diffuse low attenuation lesions on CT scans are caused by various pathologic conditions, especially differences of the intratumoral matrix. Low attenuation on CT scans was more defined than fat density and less than muscle density, the so-called near water density. We present representative cases of low attenuation lesions in correlation with their pathologic features. Intratumoral matrix showing diffuse low attenuation on CT was classified into eight groups: fatty degeneration/fatty metamorphosis, intracellular high lipid content, large amounts of lipid-laden macrophages, mucin-producing tumor, myxoid degeneration/myxoid matriX, massive necrosis, true cystic growth of the neoplasm, and massive edema. Lesions with fatty degeneration or intracellular high lipid content could be shown as negative CT attenuation. Knowledge of the neoplasms or disease processes that tend to have such pathology will lead to correct interpretation of CT scans of various organs.

Adult↗
PubMed1999

[Expression of membrane-type I matrix metalloproteinase and its correlation with gelatinase A activation in cancer cell lines].

OBJECTIVE: To study the expression of membrane-type I matrix metalloproteinase (MT1-MMP) and its correlation with gelatinase A (MMP2) activation. METHODS: Reverse transcription PCR, northern blots and western blots were employed to detect the expression levels of MT1-MMP mRNA and MMP2 protein in 4 human melanoma cell lines, 2 human lung cancer cell lines and 2 human prostate cancer cell lines. RESULTS: All the cancer cell lines expressed MT1-MMP mRNA, and the MT1-MMP mRNA level in the 4 melanoma cell lines was significantly higher than that in the lung and prostate cancer cell lines. Activated MMP2 proteins were only detected in the melanoma cell lines, whereas PG, a lung cancer cell line, which secreted pro-MMP2 and expressed low level of MT1-MMP, could not produce activated MMP2. CONCLUSIONS: The level of MT1-MMP expression was highly associated with MMP2 activation.

Blotting, Northern↗
PubMed2006

Matrix metalloproteinase-9 expression correlated with tumor response in patients with locally advanced rectal cancer undergoing preoperative chemoradiotherapy.

PURPOSE: To analyze whether the expression of matrix metalloproteinases (MMPs) and their tissue inhibitors are associated with tumor response to preoperative chemoradiotherapy in rectal cancer patients. METHODS AND MATERIALS: Forty-four patients who had undergone preoperative chemoradiotherapy were evaluated retrospectively. Treatment consisted of pelvic radiotherapy and two cycles of 5-fluorouracil plus leucovorin. Surgery was performed 6-8 weeks later. MMP-2, MMP-9, and tissue inhibitors of metalloproteinase-1 and -2 expression was analyzed by immunohistochemistry of the preradiation biopsy and surgical specimens. The intensity and extent of staining were evaluated separately, and a final score was calculated by multiplying the two scores. The primary endpoint was the correlation of expression with tumor response, with the secondary endpoint the effect of chemoradiotherapy on the expression. RESULTS: Preoperative treatment resulted in downstaging in 20 patients (45%) and no clinical response in 24 (55%). The pathologic tumor response was complete in 11 patients (25%), partial in 23 (52%), and none in 10 (23%). Positive MMP-9 staining was observed in 20 tumors (45%) and was associated with the clinical nodal stage (p = 0.035) and the pathologic and clinical response (p < 0.0001). The staining status of the other markers was associated with neither stage nor response. The overall pathologic response rate was 25% in MMP-9-positive patients vs. 52% in MMP-9-negative patients (p = 0.001). None of the 11 patients with pathologic complete remission was MMP-9 positive. CONCLUSIONS: Matrix metalloproteinase-9 expression correlated with a poor tumor response to preoperative chemoradiotherapy in rectal carcinoma patients.

Adult↗
PubMed1991

Change in the expression of a nuclear matrix-associated protein is correlated with cellular transformation.

We have identified a monoclonal antibody that recognizes a nuclear matrix-associated protein in NIH 3T3 cells. The immunofluorescence pattern consists predominantly of bright nuclear granule clusters distributed throughout the nucleoplasm, with the exclusion of nucleoli. It recognizes a protein of 190 kDa that is down-regulated to various degrees in a panel of single-oncogene-transformed NIH 3T3 cells. Its localization is similar, but not identical, to the spliceosomal speckles. p190 shows a coordinate expression during the growth cycle of nontransformed NIH 3T3 cells; it is synthesized at the highest level under growth arrest conditions. It is expressed in adult mouse brain and is also present in human IMR-90 fibroblasts.

Animals↗
PubMed1999

Temporal expression of the matrix metalloproteinase MMP-2 correlates with fibronectin immunoreactivity during the development of the vascular system in the chick embryo chorioallantoic membrane.

In this study we have examined in the chick embryo chorioallantoic membrane (ChAM) the expression of the matrix metalloproteinase 2 (MMP-2) and have correlated this parameter with the expansion of the ChAM vasculature and with the expression of 3 extracellular matrix components (fibronectin, laminin and type IV collagen), which differentially modulate angiogenesis. In the early phases of ChAM development, between d 6 and d 8 of incubation, when the increase of the ChAM vasculature is maximal, higher values of MMP-2 and, respectively, of fibronectin immunoreactive area, are detectable. These results indicate that MMP-2 activity and fibronectin expression are 2 strictly related components of angiogenesis occurring in vivo.

Animals↗
PubMed1996

Deposition of collagen VI in the extracellular matrix during mouse embryogenesis correlates with expression of the alpha 3(VI) subunit gene.

Collagen VI is a microfibrillar component of the extracellular matrix that is predicted to have an important structural role in matrix organization and a biological function in mediating cell-matrix interactions. Secreted collagen VI molecules are composed of three distinct subunits, the alpha 1(VI), alpha 2(VI), and alpha 3(VI) chains. To determine when, and in which tissues, collagen VI is likely to have a role in embryonic processes, we have analyzed the expression patterns of the three subunit chains during postimplantation mouse development by reverse transcriptase-PCR (RT-PCR), in situ hybridization, and immunofluorescence. No collagen VI protein could be detected in the mouse embryo until Day 11.5 of gestation, when low levels were localized within the mesoderm layer of the visceral yolk sac, the subepidermal matrix of branchial arches, and the vessel wall of the dorsal aorta. Levels of collagen VI mRNA and protein increased during the period from Days 12.5 to 14.5 in the visceral yolk sac, subepidermal mesenchyme, lung, gut, meninges, muscle, perichondrium, and vertebral column. The cartilage matrix of ribs and developing long bones was not stained with collagen VI antisera, but pericellular staining of chondrocytes was seen in both tissues. Low levels of collagen VI mRNA and protein were seen in the fetal liver except for the connective tissue of the liver capsule, which was highly stained. Collagen VI was first detected at significant levels in the developing heart on Day 14.5. These data demonstrate a tissue-specific onset of collagen VI synthesis and deposition in the extracellular matrix of developing mouse embryos at a much later stage of development than that reported for fibronectin or collagen I. Sensitive RT-PCR assays showed that alpha 1(VI) and alpha 2(VI) mRNAs were amplified from extracts of embryonic tissues as early as Day 7.5, while alpha 3(VI) mRNA was not detected until Day 10.5. Expression of the alpha 3(VI) gene immediately preceded the appearance of collagen VI protein in embryonic tissues. This correlation is consistent with the proposal that expression of alpha 3(VI) chains regulates the formation and secretion of collagen VI trimers and collagen VI matrix deposition during development.

Animals↗
PubMed1999

Association of chromosome territories with the nuclear matrix. Disruption of human chromosome territories correlates with the release of a subset of nuclear matrix proteins.

To study the possible role of the nuclear matrix in chromosome territory organization, normal human fibroblast cells are treated in situ via classic isolation procedures for nuclear matrix in the absence of nuclease (e.g., DNase I) digestion, followed by chromosome painting. We report for the first time that chromosome territories are maintained intact on the nuclear matrix. In contrast, complete extraction of the internal nuclear matrix components with RNase treatment followed by 2 M NaCl results in the disruption of higher order chromosome territory architecture. Correlative with territorial disruption is the formation of a faint DNA halo surrounding the nuclear lamina and a dispersive effect on the characteristically discrete DNA replication sites in the nuclear interior. Identical results were obtained using eight different human chromosome paints. Based on these findings, we developed a fractionation strategy to release the bulk of nuclear matrix proteins under conditions where the chromosome territories are maintained intact. A second treatment results in disruption of the chromosome territories in conjunction with the release of a small subset of acidic proteins. These proteins are distinct from the major nuclear matrix proteins and may be involved in mediating chromosome territory organization.

Ammonium Sulfate↗
PubMed1994

Expression of the extracellular matrix molecule thrombospondin inversely correlates with malignant progression in melanoma, lung and breast carcinoma cell lines.

Thrombospondin (TSP) is a member of a family of extracellular matrix glycoproteins that may participate in multiple aspects of the metastatic cascade. We report an inverse correlation of steady-state Thbs-1 mRNA and protein expression with malignant progression among murine melanoma and human lung and breast carcinoma cell lines. Murine K-1735 melanoma cell lines of low metastatic potential, including K-1735 lines transfected with the murine nm23-1 cDNA, expressed higher TSP levels than related highly metastatic lines. In a model system of lung carcinoma malignant progression, immortalized human bronchial epithelial cells expressed higher TSP levels than v-Ki-ras, v-Ha-ras or n-ras transfectants, which in turn expressed higher TSP levels than tumor-derived, more aggressive variants. Among 3 unrelated breast carcinoma cell lines, Thbs-1 steady-state mRNA levels were greater in the 2 non-metastatic lines than the metastatic line. Our data show that malignant progression in some cell lines is associated with reduced TSP expression. The suppressive effects of nm23-1 transfection on metastatic potential are also associated with increased TSP expression; ras transfection, which results in increased tumorigenesis, is associated with decreased TSP expression.

Animals↗
PubMed2003

[Down-regulation of metastatic phenotype in human melanoma cells by controlled expression of anti-sense matrix metalloproteinase 9].

OBJECTIVE: To investigate the correlation between matrix metalloproteinase 9 (MMP-9) expression and tumor invasion and metastasis as well, and to explore the potential application of controlled expression of target gene in tumor gene therapy. METHODS: One self-contained tetracycline-regulated retroviral vector containing anti-sense cDNA of MMP-9 was constructed and transfected into a metastatic human melanoma cell line WM451 which expressed a high level of MMP-9. Techniques such as growth rate measurment, MTT assay, (3)H-thymidine incorporation, colony forming ability in soft agar, invasion assay in Boyden chamber, as well as zymography and Western blot were applied to analyze the expression of MMPs and behaviors of tumor cells in vitro before and after gene transfection. Tumorigenecity and spontaneous metastasis were tested in nude mice. RESULTS: In the presence of exogenous tetracycline, the transfected antisense MMP-9 did not affect the endogenous level of MMP-9 in WM451 cells, and showed no significant changes in cell behaviors in comparison with that of the vector-transfected control cells. Nevertheless, withdrawal of tetracycline from the medium caused a significant down-regulation of expression and activity of MMP-9. The capacity of cell growth in vitro, colony forming ability in soft agar, invasion through Matrigel all were inhibited remarkably when compared with the controls. Spontaneous metastasis in nude mice was significantly inhibited. CONCLUSIONS: Transfection of anti-sense MMP-9 can down-regulate the invasion and metastasis of melanoma cells both in vitro and in vivo, further clarifying the important role of MMP-9 in tumor progression.

Animals↗
PubMed1994

Expression of mRNA for IL1 beta, IL6 and TGF beta 1 in developing human bone and cartilage.

Using in situ hybridization, we investigated the expression of mRNA for interleukin-1 beta (IL1 beta), interleukin-6 (IL6), and transforming growth factor-beta-1 (TGF beta 1) in sections of developing bone in human osteophytes. The expression was related to the cellular activity of alkaline phosphatase to aid in the identification of pre-osteoblast populations. IL1 beta mRNA was localized in active osteoblasts within distinct areas of intramembranous ossification. However, the expression was sporadic and appeared to occur at a specific stage of the osteoblast life cycle. There was no IL1 beta mRNA expression in any cell types during endochondral ossification. IL6 mRNA expression was located within pre-osteoblasts and in newly differentiated and matrix-secreting osteoblasts; expression was absent or reduced in flattened, inactive osteoblasts. Weak or no IL6 expression was observed in chondroblasts and chondrocytes, respectively. However, there was a close association between IL6 mRNA expression and the differentiation of mesenchymal cells into osteoblasts. TGF beta 1 expression was localized to osteoblasts apposed to bone or cartilage matrix; the intensity of expression correlated with matrix secretion. Chondroblasts and chondrocytes expressed lower but significant levels of TGF beta 1 mRNA; the expression was lost with the progression to calcifying cartilage. The three cytokines studied were differentially expressed both temporally and spatially, suggesting different roles for each in osteoblast and chondrocyte function.

Alkaline Phosphatase↗