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PubMedDate not supplied

[A system of mechanical integration of tissue as the basic regulation system at the tissue level of organization].

A new concept for tissue--level regulation system is proposed. This concept is based on three groups of facts: 1) possibility of regulation of tissue behavior by fields of mechanical tension; 2) correlation between changes in mechanical properties of the tissue and its biological behavior at different stages of blastomogenesis; 3) regulative role of tissue--specific (endo- and exo)-genic factors which influence directly the mechanical properties of the tissue. This system is called the system of the mechanical integration of the tissue. Some problems concerning the action mechanism of this system are discussed.

Animals↗
PubMed1973

The resistance of certain tissues to invasion: penetrability of explanted tissues by vascularized mesenchyme.

If puppy tissues are explanted onto the chick chorioallantoic membrane, those tissues which normally have a blood supply are rapidly invaded by vascularized mesenchyme of host origin. Hyaline cartilage, a tissue virtually devoid of blood vessels, is impenetrable by proliferating mesenchyme of the host, while calcified cartilage, which normally is vascularized, is penetrable. The stroma of the cornea, another normally avascular tissue, is readily penetrable, but Descemet's membrane forms a barrier to invasion by host tissues. The experimental system used permits the design of experiments in which the study of factors responsible for the resistance of tissues such as cartilage to invasion can be undertaken.

Animals↗
PubMed1995

[Correlation between tissue blood flow and tissue concentration of 5-FU and its metabolite in hepatic metastasis model for rats].

Correlation between 5-FU (20mg/kg) administrated via the peripheral vein and tissue concentration of its metabolite was studied in hepatic metastasis model prepared for rats. The measurement of tissue samples collected 30 min. after the 5-FU administration suggested a possible negative correlation between the F-dUMP concentration and the blood flow in the normal hepatic tissue of the control group and the tumor tissue in the metastasis group. In administering 5-FU, a time-dependent anticancer drug, to the tumor rich in the tissue blood flow, washing-off effect of the drug by blood outflow cannot be neglected. Some device of prolonging the exposure time of anti-cancer agent to the tumor tissue will be necessary.

Animals↗
PubMed1994

Human multiple tissue western blots: a new immunological tool for the analysis of tissue-specific protein expression.

Human multiple tissue Western (MTW) blots are premade immunoblots prepared using proteins isolated from adult human tissue. The proteins are isolated from whole tissue homogenates under conditions designed to minimize proteolysis and to ensure maximal representation of tissue-specific proteins. Sodium dodecyl sulfate (SDS) solubilized proteins are fractionated by SDS polyacrylamide gel electrophoresis and electroblotted onto polyvinylidene fluoride membranes to generate blots ready for incubation with researcher-supplied antibodies. Each lane of an MTW blot contains an equivalent amount of total protein, allowing for the analysis of tissue-specific expression of a particular protein(s). The utility of MTW blots for Western blot applications was demonstrated by the detection of various cytoskeletal proteins and members of the annexin family of calcium-dependent, membrane-binding proteins. Several of these antigens were detected in separate cycles of antibody incubations using the same MTW blot. This approach is possible using a stripping procedure that allows the researcher to selectively remove both primary and secondary antibodies in a single incubation. The ease of multiple reprobings makes MTW blots both economical and convenient research tools for Western blot analyses of human tissue-specific proteins.

Adult↗
PubMed1994

[Tissue concentration of tegafur suppository in patients with head and neck cancer--concentration of 5-FU in cancer tissue].

Fifty patients with head and neck cancer were treated with tegafur suppository for 7 days preoperatively. The tissues were obtained during surgical operation and the concentrations of 5-FU in cancer tissue, normal tissue and blood were measured. It was revealed that a high concentration of 5-FU was seen in cancer tissue and then metastatic lymph nodes. The 5-FU concentration in cancer tissue was parallel with T stage of the patients. Subsites which showed a high concentration of 5-FU were nasal-paranasal cavity, tongue and mesopharynx. The tegafur suppository was useful because of the high concentration in cancer tissue and metastatic lymph nodes without any obvious side effects in the head and neck region.

Adult↗
PubMed1993

[Relationship between tissue concentrations of 5-FU and degeneration of tissues after UFT administration in patients with bladder tumor].

The relationship between the 5-FU concentration and tissue degeneration was studied in the bladder tumor tissue after UFT administration. In 12 patients with bladder tumor, UFT 400 mg/day was administered orally for about 2 weeks before TUR, and tegaful, 5-FU and uracil concentrations were examined in the blood and the tumor tissue taken about 6 hours after the last administration. Tumor tissue was also taken before and after the UFT administration, and the degree of cell degeneration due to UFT administration were evaluated by light and electron microscopy. The 5-FU concentration was significantly higher in the tumor tissue (0.078 +/- 0.091 microgram/g) than in the serum (0.017 +/- 0.010 microgram/ml). Signs of degeneration were observed in tumor cells after UFT administration in all 6 patients in whom the tumor tissue 5-FU concentration was 0.046 microgram/g or higher. Mitosis was not increased after UFT administration in any of the 12 patients.

Aged↗
PubMed1993

Temporal and spatial immunolocalization of cytokines in murine chronic granulomatous tissue. Implications for their role in tissue development and repair processes.

BACKGROUND: Cytokines have profound effects on various aspects of granulomatous tissue formation. However, there is little information regarding their distribution during tissue development. This study investigated the temporal and spatial distribution of transforming growth factor-beta (TGF-beta), platelet-derived growth factor (PDGF), epidermal growth factor (EGF), basic fibroblast growth factor (bFGF), tumor necrosis factor-alpha (TNF-alpha), interleukin-1 alpha (IL-1) and IL-1 beta in developing granulomatous tissue. EXPERIMENTAL DESIGN: Murine chronic granulomatous air pouches were induced and full thickness biopsies taken at intervals up to 28 days. Samples were prepared for immunohistochemistry and labeled using antibodies against TGF-beta, bFGF, PDGF, EGF, TNF-alpha, IL-1 alpha and IL-1 beta. RESULTS: Immunoreactivity to TGF-beta, PDGF, TNF-alpha, IL-1 alpha and IL-1 beta was localized to a proportion of macrophages within the granulomatous tissue. Immunopositive macrophage numbers increased with time, and with the exception of PDGF were associated with areas of fibrogenesis between days 14 to 28. Heterogeneous labeling of capillaries for EGF was observed within the granulomatous tissue juxtaposed to dermal musculature. Diffuse labeling of bFGF, associated with extracellular matrix, was always observed. After day 14, bFGF immunoreactivity was discretely localized to endothelial cells and the basement membrane of vessels within the granulomatous tissue. TGF-beta immunoreactivity was also associated with extracellular matrix components, being most intense in the area of fibrogenesis between 14 and 28 days. Occasional fibroblasts were also labeled with TGF-beta in this region. CONCLUSIONS: The spatial and temporal confinement of the individual cytokines suggests that a sequential coordinated process of repair and fibrosis is occurring. It is hoped that these observations will provide a more effective therapeutic approach for the sequential application of cytokines in abnormalities of wound healing.

Animals↗
PubMed1993

High-purity resident tissue macrophage isolates from human synovium and periprosthetic tissues using immunomagnetic techniques.

Destruction of periarticular and periprosthetic bone by activated macrophages, a process often termed "macrophage mediated osteolysis," is recognized as a leading mechanism of aseptic arthroplasty failure. To develop effective interventional approaches and increase the longevity of implanted joint prostheses, the pathobiology of activated human-synovium-derived macrophages needs to be better characterized. The first step toward achieving this research objective is the acquisition of pure populations of macrophages from human synovial tissue. A simple, fast, and highly efficient method for isolating a relatively pure population of macrophages from periprosthetic tissue received from either primary or secondary arthroplasty is presented. This technique uses murine monoclonal antibodies (IgG) that recognize a phagocyte-specific marker, CD68, for primary binding, and sheep anti-murine IgG antibodies bound to polystyrene-coated magnetic microspheres for secondary binding. While the primary antibody specifically labels CD68-positive phagocytes in the digestion of synovial and periprosthetic tissue, the secondary antibody bound to polystyrene-coated iron oxide beads facilitates the removal of CD68-positive cells from CD68-negative cells by anchoring the former with a magnet. This protocol requires centrifugation only in the washing steps, which reduces the frequency of cell death and altered cell morphology. The patient population includes three primary and eight revision arthroplasties. The tissue macrophage isolation protocol yielded on average 4 x 10(5) cells/g tissue, of which 91% were viable nonspecific esterase positive macrophages. The experimental results suggest that immunomagnetic beads coupled to anti-CD68 enable the isolation of a purified population of resident tissue macrophages suitable for further biologic characterization.

Adult↗
PubMed1993

Inhibitory properties of full-length and truncated recombinant tissue factor pathway inhibitor (TFPI). Evidence that the third Kunitz-type domain of TFPI is not essential for the inhibition of factor VIIa-tissue factor complexes on cell surfaces.

Human tissue factor pathway inhibitor (TFPI) is a plasma protease inhibitor that consists of three tandem Kunitz-type inhibitor domains flanked by a negatively charged NH2 terminus and a positively charged COOH-terminal tail. Previous studies have shown that the first and second Kunitz-type domains in TFPI are involved in the inhibition of factor VIIa and factor Xa activity, respectively. In the present study, we have compared the inhibitory properties of full-length recombinant TFPI and a truncated form of TFPI lacking the third Kunitz-type domain and COOH-terminal tail (TFPI1-161) with respect to inhibition of factor VIIa-tissue factor complexes on the surface of a human bladder carcinoma cell line J82. Full-length TFPI and TFPI1-161 were kinetically indistinguishable with respect to neutralization of the proteolytic activity of preformed complexes of factor VIIa-tissue factor on the J82 cell surface in the absence of factor Xa. Equimolar amounts of factor Xa augmented the anticoagulant activity of both preparations of TFPI to the same extent, and both preparations of TFPI were equally effective in inhibiting factor VIIa-tissue factor amidolytic activity in solution phase. In addition, plasma concentrations of both forms of TFPI, in stoichiometric complex with factor Xa, inhibited cell surface factor VIIa-tissue factor proteolytic activity markedly faster than plasma levels of antithrombin III, even in the presence of 1 unit/ml heparin. The results of displacement studies suggested slight differences in the affinity of the two TFPI molecules for the cell surface in that approximately 5% of a VIIa.TF.Xa.TFPI1-161 quaternary complex on J82 cells was displaceable from the cell surface by high concentrations of factor VIIa (10-100 nM), whereas only 1-2% of a VIIa.TF.Xa.TFPI complex was displaceable under comparable conditions. Pretreatment of the cells with TFPI/Xa alone or together with R152E factor VII, followed by factor VIIa treatment, revealed significant differences in the two TFPI forms with respect to the degree with which offered factor VIIa could restore factor X activation on the cell surface. These differences notwithstanding, our collective findings indicate that the third Kunitz-type domain and/or COOH-terminal tail of TFPI is not essential for the inhibition of cell surface factor VIIa-tissue factor complexes and suggests that TFPI1-161 may be a useful therapeutic agent in the treatment of thromboembolic episodes.

Antithrombin III↗
PubMed1995

Kinetics of the inhibition of tissue factor-factor VIIa by tissue factor pathway inhibitor.

Tissue factor-factor VIIa catalysed activation of factor IX is inhibited by the complex of tissue factor pathway inhibitor (TFPI) and factor Xa. At present, no information is available as to what extent the kinetics of complex formation between TFPI and factor Xa during factor X activation contribute to the overall rate of inactivation of the factor X converting complex. We have determined the kinetic parameters of the individual reactions, i.e. factor X activation, formation of the TFPI-factor Xa complex, and inactivation of tissue factor-factor VIIa by the TFPI-factor Xa complex. We modelled the overall reaction by assuming a two-step reaction: factor Xa generated by tissue factor-factor VIIa forms a reversible complex with TFPI and in the second step this complex forms a reversible quaternary complex with tissue factor-factor VIIa. The validity of the model was demonstrated by analysis of factor Xa generation curves in the presence of TFPI. Independently determined constants for factor X activation (kcat = 12 s-1, Km = 70 nM) and inhibition of tissue factor-factor VIIa by TFPI-factor Xa complex (rate constant of inhibition of 1.1 x 10(8) M-1S-1) were used. The association rate constant of the formation of the TFPI-factor Xa complex was estimated by fitting the model to the data.(ABSTRACT TRUNCATED AT 250 WORDS)

Amino Acid Sequence↗
PubMed1996

Immunohistochemical localization of insulin-like growth factor binding protein-1, -3 and -4 in human fetal tissues and their analysis in media from fetal tissue explants.

The actions of insulin-like growth factor (IGF) II that are important in the regulation of fetal growth and development, are modulated by IGF binding proteins (IGFBPs). We have determined the cellular distribution of IGF-II and IGFBP-1, -3 and -4 in 12-week gestation human fetal tissues using immunocytochemistry. IGF-II immunostaining was found in all organs examined, with strongest immunoreactivity in spinal ganglia, tubular cells of the mesonephros and peri- and epidermal layers of the skin. The immunoreactivity distribution of all IGFBPs was similar to that of IGF-II except lung, hepatic parenchyma, fibrocytes of connective tissue and cells of the growth plate in the cartilage. When conditioned media from skin, liver, lung and kidney explants were analyzed, phosphorylated IGFBP-1 was only detected in liver samples whereas IGFBP-3 was found in all media. Weak immunoreactivity of IGFBP-4 was seen in media from lung tissue. To determine whether proteolytic degradation of IGFBPs were responsible for the different IGFBP levels, cell-free conditioned media were incubated with recombinant human IGFBPs. At neutral pH only proteolysis of IGFBP-4 was observed in media from skin and lung tissue. Upon acidification of the medium samples, IGFBP-1 fragments were formed in skin-derived medium and IGFBP-3 was cleaved by medium from lung and kidney tissue. Acid-activated proteolytic activity against IGFBP-4 was found in the media from lung and liver. These findings suggest that IGFBP proteases may be important in locally defining the concentrations of IGFBPs and contribute to tissue-specific growth response to IGFs.

Antibodies, Monoclonal↗
PubMed1996

[The tissue cage in dogs--a pharmacologic model for the representation of plasma and tissue kinetics].

Determination of pharmacokinetic data from plasma often is not sufficient in order to predict or to explain the clinical efficacy of drugs, e.g., in non steroidal antiinflammatory drugs (NSAID) with short elimination half lives in plasma a discrepancy appears between elimination half life and clinical effect. We have studied the tissue kinetics of a drug having a long elimination half life (naproxen) in comparison with phenylbutazone and flunixin, having a short elimination half life in dogs after oral application. Tissue fluid was obtained by using so called "tissue cages" implanted laterally in the neck. An inflammatory response was produced by injecting 1-2 ml of 2% carrageenan into the chamber. The drug concentrations were determined throughout the experiments both in plasma and tissue fluid. Naproxen concentrations (elimination half life of about 72 h in dogs) achieved equilibrium between tissue fluid and plasma concentration. In the case of phenylbutazone, concentration in tissue fluid declined with a definitely longer half life than in plasma and exceeded plasma concentrations after some hours. Flunixin concentrations in plasma and exudate attained equilibrium after 2-5 h. Of clinical importance is the finding that after this time flunixin accumulated in inflammatory exudate and the concentration in exudate exceeded that in plasma two to ten times, then declined with an almost identical half-life. The number of leukocytes in exudate as a measure of inflammation was reduced during 2 days after phenylbutazone, 3-4 days after flunixin and 5-7 days after naproxen. This allows therapy with a lower dosage than calculated on the basis of plasma concentrations in the case of phenylbutazone and flunixin, possibly also with other NSAIDs having a short plasma half life.

Animals↗
PubMed1976

The autoimmune response to male reproductive tissues of rabbits. IV. Induction of autosensitization to central accessory tissue by the intraabdominal release of endogenous secretions.

A study is described in which tissue- and secretion-specific autosensitization was induced in adult male rabbits through intraabdominal cannulation of one or more of their central accessory glands. Both primary and secondary humoral antibodies were elicited by this procedure, as determined by tanned cell hemagglutination and passive hemolysis, i.e., complement fixation. The secondary antibody responses were elicited by (i) cannulation of animals which had been previously stimulated by cryosurgery or combined cryosurgery and injection of pooled accessory tissue extract, and (ii) isoinjection of previously cannulated animals with accessory tissue extract. Primary antibody responses were less in animals castrated at the time of cannulation compared to those in noncastrated animals; but, paradoxically, subsequent challenges with tissue extract induced higher secondary antibody titers in castrated animals. These observations may be explained in castrates by (i) reduced uptake of antibodies--a result of the sparing effect on circulating antibodies in castrated animals because of accessory tissue atrophy, or (ii) increased production of antibodies through postcastration immune enhancement. In noncastrates secondary antibody depression may be related to (i) increased absorption of antibodies by an accessory gland complex which is much larger than that found in castrates, or (ii) tolerance, due to exposure of the antibody-producing system to excess accessory tissue antigen.

Abdomen↗
PubMedDate not supplied

[Indications for the cryopreservation of ovarian tissue. Study Group for the Cryopreservation of Ovarian Tissue].

A number of questions should be envisioned before proposing the indications for clinical use of ovarian tissue cryopreservation (OTC). With what goal is ovarian tissue being preserved? To protect ovarian function which includes the ovarian endocrine secretions and the monthly release of a mature oocyte assuring the fertility of the patient; preservation of fertility is in fact the key goal. To whom should OTC be offered? In theory, to all women whose ovarian function is threatened in a physiological, pathological or iatrogenic manner. In practice, the threat to the follicular reservoir occurring with cancer chemotherapy is the best established indication. Other indications may in the future also be deemed appropriate-when human clinical use of OTC will have proven itself effective. For the present, it is preferable to reserve OTC use to patients under 35 years old who, in whatever manner, would have undergone a very severe cutback of their follicular reserve. What quantity of ovarian tissue should be extracted? It seems to us preferable to only remove one ovary, thereby leaving the patients with the possibility of undergoing spontaneous fertility, so that the frozen tissue need only be used if the ovary left in place should lose its function. How should use of the frozen tissue be directed? Among the three theoretic possibilities: of tissue autograft, follicular maturation in vitro, and heterograft, only the autograft appears realizable in the near future. However, presently, pregnancies using this technology have only been obtained in three animal species. For the near future, it appears to us that resort to OTC must remain infrequent and only performed in the setting of clinical research protocols. Priority should be given to continued basic research as many key points of OTC practice still need to be clarified.

Cryopreservation↗
PubMed1998

Differential regulation of mouse uncoupling proteins among brown adipose tissue, white adipose tissue, and skeletal muscle in chronic beta 3 adrenergic receptor agonist treatment.

Uncoupling proteins (UCPs) are inner mitochondrial membrane transporters that dissipate the proton gradient, releasing stored energy as heat, without coupling to other energy-consuming processes. Therefore, the UCPs are thought to be important determinants of the metabolic efficiency. To elucidate relationships between the UCPs expressions and insulin sensitivity improvement, we treated KK-Ay mice with beta 3 adrenergic receptor agonist for 21 days and examined the changes of the UCPs mRNA expressions in various tissues. Chronic treatment of a specific beta 3 adrenergic receptor agonist, CL316,243 (0.2 mg/kg body weight/day s.c.) markedly increased the expressions of uncoupling protein 1 (UCP1), uncoupling protein 2 (UCP2), and uncoupling protein 3 (UCP3) by 14-fold, 6-fold, and 16-fold, respectively, in the brown adipose tissue (BAT). The UCP1 and UCP3 mRNA expressions in the white adipose tissue (WAT) were also increased by 12-fold and 9-fold, respectively, but the UCP2 mRNA expression was not changed in this tissue. Interestingly, the UCP2 and UCP3 mRNA expressions were strikingly decreased in the skeletal muscle and heart. Particularly, the UCP3 mRNA expression level in the skeletal muscle was dropped to 10% of that of the saline-treated control mice, indicating that the UCPs mRNA expressions are regulated in tissue-specific ways. The concentrations of plasma insulin and circulating free fatty acid (FFA) were significantly decreased, suggesting that they correlate with the reductions of the UCP2 and UCP3 mRNA expressions in the skeletal muscle and heart. It has been thought that the UCP1 and UCP3 mRNA expressions in the BAT and WAT are mainly controlled by the hypothalamus via the sympathetic nervous system, while the levels of insulin, FFA or both may play important roles in the control of the UCP2 and UCP3 mRNA expressions in the skeletal muscle an heart.

Adipose Tissue↗
PubMed1996

Expression of mRNA for matrix metalloproteinases and tissue inhibitors of metalloproteinases in periodontitis-affected human gingival tissue.

It is known that the host responds to an increased concentration of collagenase [or matrix metalloproteinase (MMP)-1] by preferentially expressing mRNA for the tissue inhibitor of metalloproteinase-1 (TIMP-1) in order to overcome tissue destruction due to periodontitis. To further elucidate the relation between MMPs and TIMPs in periodontitis-affected tissues, the expression of mRNA for MMP-1, -3 and -8, and TIMP-1 and -2, in 10 gingival samples from patients and five from healthy individuals was assessed by reverse transcription-polymerase chain reaction. The diseased group showed significantly higher levels of MMP-1, -3, -8 and TIMP-1 mRNA relative to beta-actin than the control group (mean +/- SE: diseased vs healthy (%): 0.26 +/- 0.05 vs 0.018 +/- 0.0040 for MMP-1; 0.09 +/- 0.16 vs 0.063 +/- 0.016 for MMP-3; 0.068 +/- 0.017 vs 0.006 +/- 0.0010 for MMP-8; 12.66 +/- 2.90 vs 2.71 +/- 0.54 for TIMP-1; p < 0.01). TIMP-2 did not significantly differ between the two groups (1.79 +/- 0.33 vs 1.42 +/- 0.53; p > 0.05). The preferential increase in the level of MMP-3 mRNA relative to that of MMP-1 and -8 in inflamed gingiva would be relevant to tissue destruction because MMP-3 is a broad-spectrum MMP and a pivotal activator of latent MMP-1 and -8. Therefore, the overall increase in MMP-1, -3 and -8 mRNA in periodontitis-affected gingiva might account for a concerted action of MMPs during connective tissue destruction in periodontitis.

Case-Control Studies↗
PubMed1988

Tissue plasminogen activator mRNA in murine tissues.

The urokinase-type and tissue-type plasminogen activators are the two enzymes found in mammals, which specifically convert the zymogen plasminogen to plasmin. Using cDNA probes, we have assayed for the presence of the two types of plasminogen activator mRNAs in murine tissues. We demonstrate that tissue-type plasminogen activator mRNA can be detected in a wide variety of tissues. In contrast, the accumulation of urokinase-type plasminogen activator mRNA is observed in only a few of the tissues analyzed. Using an S1 nuclease assay, we demonstrate that the tPA mRNA detected contains the complete sequences encoding the non-protease finger, growth-factor and kringle domains.

Animals↗
PubMed1989

Brown adipose tissue in lean and fat selection lines of sheep identified by immunodetection of uncoupling protein in western blots of tissue homogenates.

1. Uncoupling protein (UCP) was purified from perirenal adipose tissue of 2-day-old lambs by a procedure involving Triton solubilization and hydroxyapatite treatment. It has an apparent Mr of 34,000. 2. Rabbit anti-sheep UCP and rabbit anti-rat UCP each cross-reacted with both rat and sheep UCP in Western blots, indicating that the major antigenic determinants of the sheep UCP and rat UCP are similar. 3. In Western blots, the anti-sheep UCP showed tissue specificity by detecting a band corresponding to UCP only in brown adipose tissue, but not in heart or liver homogenates. 4. The Western blotting procedure was used to analyse sheep tissues. UCP was detected in samples of perirenal, omental, back and lymph node fat from 2-day-old lambs, but not in heart, liver, muscle or kidney samples. 5. UCP was not detected in any tissue samples from 34-day-old or 7-month-old lambs. 6. Comparison of the amount of UCP in perirenal fat of 2-day-old lambs from lean, fat and control selection lines, using the Western blotting procedure, showed no apparent difference.

Adipose Tissue↗