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PubMed1990

Microcalorimetric studies on metabolism of hepatic tissue. I. A methodological study of normal tissue.

In the present study, the heat production of liver biopsies (5-8 mg) was measured by a microcalorimetric technique. Tissue incubated in Leibowitz L-15 medium (L-15) showed a higher metabolic rate compared to tissue incubated in a medium without substrate 2.8 microW/mg and 1.75 microW/mg, respectively. Heat production was found to be related to weight density. No difference in the metabolic rate was found after organ perfusion in comparison to nonperfused liver. Storage in medium L-15 at 4 degrees C caused a lower rate of heat production, but if the tissue was stored in an electrolyte balance solution without substrate, no difference was seen compared to fresh tissue. Recording heat production with the present calorimetric technique is relatively simple and rapid and allows measurement of small samples.

Animals↗
PubMed2006

Expression of human DNA methyltransferase 1 in colorectal cancer tissues and their corresponding distant normal tissues.

BACKGROUND AND AIM: DNA methylation plays an important role during colorectal cancer (CRC) carcinogenesis. DNA methyltransferase 1 (DNMT1) is responsible for maintaining DNA methylation. We addressed the significance of DNMT1 expression in CRC. MATERIALS AND METHODS: We measured the expression of DNMT1 in CRC tissues and in their corresponding distal normal colorectal mucosa using reverse transcriptase-polymerase chain reaction and immunohistochemical analysis. RESULTS: The mean +/- SD of DNMT1 mRNA in CRC tissues was 1.04 +/- 0.36, which was significantly higher than that in their corresponding distal normal colorectal mucosa (0.58 +/- 0.44, P < 0.05). Fifty-eight out of 77 (75.3%) CRC tissues and only 30 out of 77 (39%) corresponding distant normal colorectal mucosa showed immunoreactivity (P < 0.001). We also found that the immunoreactivity of DNMT1 was higher in mucosa adjacent to cancer than in corresponding normal colorectal mucosa; high immunoreactivity was significantly correlated with poor differentiation in CRC tissues (P = 0.008). No significant associations were found between DNMT1 immunoreactivity and the following variables: age, sex, locations of cancer, Duke's phase, and the presence of lymph-node metastasis. CONCLUSION: These findings suggested that DNMT1 was associated with the malignant phenotype, and dysregulation of DNMT1 expression was present in tumor cells of CRC.

Adult↗
PubMed2002

Human tissue transglutaminase enzyme linked immunosorbent assay outperforms both the guinea pig based tissue transglutaminase assay and anti-endomysium antibodies when screening for coeliac disease.

UNLABELLED: Anti-endomysium antibodies (EMA) and antigliadin antibodies (AGA) are widely used when screening for coeliac disease (CD), although their specificity and sensitivity are suboptimal. The guinea pig tissue transglutaminase (tTG) assay also did not prove to be superior. A newly developed enzyme linked immunosorbent assay (Celikey), based on human tTG, might however have a better performance. We therefore investigated the sensitivity and specificity of this human IgA tTG assay in 101 patients with aspecific gastrointestinal complaints and compared this to guinea pig IgA tTG, AGA and EMA. A total of 52 patients with CD were investigated and 49 patients without CD. All had a small bowel biopsy. Our results showed that human IgA tTG had a sensitivity of 96% and a specificity of 100%. Guinea pig IgA-tTG had a sensitivity of 96% and a specificity of 92%. EMA had a sensitivity of 92% and a specificity of 90%. Both IgA AGA and IgG AGA had a sensitivity of 83% whilst having a specificity of 86% and 80% respectively. CONCLUSION: both the human IgA tissue transglutaminase enzyme linked immunosorbent assay and the guinea pig IgA tissue transglutaminase assay could better identify patients with coeliac disease than IgA anti-endomysium antibodies. Although in a larger series of control patients the specificity for the human IgA tissue transglutaminase enzyme linked immunosorbent assay might fall below 100%, in our opinion this is currently the serological method of choice in identifying patients with coeliac disease in the absence of IgA deficiency.

Adolescent↗
PubMed2003

NK1, NK2, NK3 and CGRP1 receptors identified in rat oral soft tissues, and in bone and dental hard tissue cells.

The distribution of the tachykinin receptors neurokinin-1 (NK1), neurokinin-2 (NK2) and neurokinin-3 (NK3), and the calcitonin gene-related peptide-1 (CGRP1) receptor were examined in rat teeth and tooth-supporting tissues by immunohistochemical methods and light and confocal microscopy. Western blot analysis was performed to identify the NK1- and the CGRP1-receptor proteins in the dental pulp. The results showed that odontoblasts and ameloblasts, cementoblasts and cementocytes, osteoblasts and osteocytes are all supported with the tachykinin receptors NK1 and NK2, but a distinct, graded cellular labeling pattern was demonstrated. The ameloblasts were also positive for CGRP1 receptor. Blood vessels in oral tissues expressed the tachykinin receptors NK1, NK2 and NK3, and the CGRP1 receptor. Both gingival and Malassez epithelium were abundantly supplied by NK2 receptor. Pulpal and periodontal fibroblasts demonstrated NK1 and NK2 receptors. Western blot analysis identified both the NK1- and the CGRP1-receptor proteins in the dental pulp. These results clearly indicate that the neuropeptides substance P, neurokinin A, neurokinin B and CGRP, released from sensory axons upon stimulation, directly modulate the function of the different types of bone and dental hard tissue cells, and regulate functions of blood vessels, fibroblasts and epithelial cells in oral tissues.

Animals↗
PubMed1996

Immunohistochemical localization of inositol 1,4,5-trisphosphate receptors in non-neural tissues, with special reference to epithelia, the reproductive system, and muscular tissues.

Although the pharmacological properties and distribution of inositol 1,4,5-trisphosphate (IP3)-sensitive calcium stores vary considerably among tissues, studies of its localization have been devoted mostly to the central nervous system. In this report we have analyzed the localization of IP3 receptors in diverse non-neural tissues of the mouse, using polyclonal antibodies raised against purified IP3 receptors through immunoblotting and immunohistochemistry. These antibodies mainly recognized type 1 IP3 receptors, although they also reacted with other types of IP3 receptors. The receptors were localized in the apical surface areas of highly polarized epithelia, such as the choroid plexus, retinal pigment epithelium, and columnar epithelium lining the interlobular ducts in the sublingual and submaxillary salivary glands. Immunoelectron microscopy of choroidal cells revealed that IP3 receptors are localized on the surfaces of several structures, including clear vesicles, tubules and vesicular profiles of smooth endoplasmic reticulum, rough endoplasmic reticulum and a part of the nuclear envelope, as well as clusters of ribosomes in the cytoplasmic matrix. The surface areas of ciliated epithelia, such as those of the trachea and oviduct, also stained positive. The cytoplasmic distribution was homogeneous in mesangial cells, myoepithelial cells, and endothelial cells accompanying muscle, as well as in a population of endocrine cells. Intense immunostaining was found in the surface areas as well as in the cytoplasm of diverse smooth muscle cells. Staining intensity of smooth muscle varied among cells in the same tissue. Staining was intense in the cytoplasm of premature oocytes in the primary follicle, but then attenuated as these cells matured. The Sertoli cells with clusters of elongating maturing sperm were stained, but mature sperm were unstained. These results indicate a heterogeneous cellular distribution, and possibly a heterogeneous subcellular distribution, of a population of IP3 receptors in a variety of non-neural tissues.

Animals↗
PubMed2005

Tissue elasticity estimation with optical coherence elastography: toward mechanical characterization of in vivo soft tissue.

High-resolution imaging provides a significant means for accurate material modulus estimation and mechanical characterization. Within the realm of in vivo soft tissue characterization, particularly on small biological length scales such as arterial atherosclerotic plaques, optical coherence tomography (OCT) offers a desirable imaging modality with higher spatial resolution and contrast of tissue as compared with intravascular ultrasound (IVUS). Based on recent advances in OCT imaging and elastography, we present a fully integrated system for tissue elasticity reconstruction, and assess the benefits of OCT on the distribution results of four representative tissue block models. We demonstrate accuracy, with displacement residuals on the order of 10(-6) mm (more than 3 orders of magnitude less than average calculated displacements), and high-resolution estimates, with the ability to resolve inclusions of 0.15 mm diameter.

Angiography↗
PubMed2006

Protective effect against 17beta-estradiol on neuronal apoptosis in hippocampus tissue following transient ischemia/recirculation in mongolian gerbils via down-regulation of tissue transglutaminase activity.

We analyzed the protective effect of 17beta-estradiol (17beta-ED) injection against delayed neuronal death in the hippocampus tissue of the brain in Mongolian gerbils after transient ischemia/recirculation treatment, especially in relation with bcl-2 gene expression and enzymatic activity changes of caspase-3 and tissue transglutaminase (tTGase). Daily intraperitoneal injection of 17beta-ED to the animal after the ischemia stimulated the expression of an apoptosis suppressor gene, bcl-2, in the hippocampal tissue for a week. The gradually increasing apoptotic enzyme activity of caspase-3 and increased number of TUNEL positive fragmented neuronal nuclei caused by ischemic attack in the gerbil brain were clearly suppressed by 17beta-ED administration. The reduced activity and enzyme protein of tTGase, a neurodegenerative marker of apoptosis in the hippocampus after ischemia, were also restored to nearly normal levels by 17beta-ED injection. These results suggest that daily 17beta-ED administration to the gerbil after transient ischemic insult with progressing neuronal deteriorative changes in hippocampus tissue can effectively prevent apoptotic changes through a molecular cascade involving gene expression regulation.

Animals↗
PubMed1988

Apparent ornithine decarboxylase activity, measured by 14CO2 trapping, after frozen storage of rat tissue and rat tissue supernatants.

Ornithine decarboxylase (ODC) activity of rat tissues was measured by the standard 14CO2 trapping method after frozen storage (-60 or -70 degrees C) of the tissues or their 105,000g supernatants. True ODC activity was determined by two methods: (a) addition of the inhibitors alpha-difluoromethylornithine (DFMO), a specific irreversible inhibitor of ODC, or aminooxyacetate (AOA), an inhibitor that blocks the decarboxylation of ornithine by mitochondrial enzymes; and (b) chromatographic analysis of the reaction products. In the frozen supernatants of liver and spleen, ODC activity changed only slightly after 1 day but increased 29 and 14%, respectively, by 30 days; activity in kidney supernatant decreased 17% after 1 day and remained near that level at 30 days. Kidney and spleen ODC activity was inhibited 90-100% by DFMO, but apparent liver ODC activity was inhibited only 60-75%. In the supernatant prepared from tissue stored frozen for 1 day, apparent ODC activity in liver increased 500% over that activity in the freshly prepared supernatant; at 23 days, apparent activity increased 755% for liver and 121% for kidney. After 23 days, DFMO did not inhibit apparent ODC activity in supernatants from frozen liver and inhibited ODC in frozen kidney by only 49%. With AOA, the ODC activities of the fresh and frozen supernatants were similar, indicating that the large increase in apparent ODC activity in frozen tissue was due to artifacts from the metabolism of ornithine via the mitochondrial pathway. HPLC analysis of the reaction products resulting from the incubation of uniformly labeled [14C]ornithine with the fresh and frozen preparations indicated no increase in putrescine with the frozen preparation.(ABSTRACT TRUNCATED AT 250 WORDS)

Aminooxyacetic Acid↗
PubMed1976

Cholesterol sulfate in rat tissues. Tissue distribution, developmental change and brain subcellular localization.

1. A reliable micromethod for the determination of the tissue level of cholesterol sulfate has been developed. Cholesterol sulfate was separated from the bulk of the free cholesterol by silica gel column chromatography, and the cholesterol sulfate fraction subjected to benzoylation. A small amount of contaminating free cholesterol and other lipids remaining in this fraction were converted to benzoyl esters while the cholesterol sulfate remained unreacted. The cholesterol sulfate was then separated from the benzoylated contaminants by a second silica gel chromatography column and subjected to solvolysis. The liberated cholesterol was determined by gas-liquid chromatography. 2. The cholesterol sulfate contents of the visceral organs of 43-day-old rats were determined. Every tissue examined contained small amounts of this sulfate. Kidney contained the highest concentration of cholesterol sulfate (250-300 mug/g dry tissue weight) followed by spleen (77 mug/g), adrenal gland (50-70 mug/g) and lung (50-57 mug/g). 3. In brain, cholesterol sulfate level rises sharply from 17 mug/g dry weight in 7-day-old rats to more than 50 mug/g in 15-day-olds, then it declines rapidly to 15 mug/g in the 40-day-olds and this level is maintained to adulthood. The developmental pattern in the liver resembles that in the brain, except that the peak is somewhat flatter with the highest value (60 mug/g dry weight) occurring in the 21-day-old animal. In contrast to the above two tissues, the level of kidney cholesterol sulfate increases steadily from 15 mug/g in 7-day-olds and reaches the adult level of approx. 200 mug/g in 50-day-olds. 4. The highest level of cholesterol sulfate in subcellular fractions of rat brain occurred in a fraction rich in nerve endings. The level here was 10 times higher than that in the mitochondrial fraction, which contained the lowest levels of this steroid sulfate.

Adrenal Glands↗
PubMed1989

The relation between thromboxane and prostaglandin synthesis in human decidua tissue: a comparison of eicosanoid synthesis in minced tissue with that in a cell-free preparation.

Radiotracer studies and radioimmunoassay measurements demonstrate that minced tissues of human decidua produce chiefly thromboxane B2 (TxB2) (70% of total eicosanoids) and small amounts of prostaglandin F2 alpha (PGF2 alpha) (13%) PGD2 (8%), 6-keto-PGF1 alpha (5%) and PGE2 (4%). Inhibition of thromboxane synthesis with a specific inhibitor (OKY-1581: sodium (E)-3-[4(-3-pyridylmethyl)-phenyl]-2-methyl propenoate) increased prostaglandin formation in general, with the main product being PGF2 alpha (38%), a nonenzymic derivative of PGH2. Crude particulate fractions prepared from the same tissue synthesized two major products from [3H]arachidonate, TxB2 and 6-keto-PGF1 alpha (54 and 30%, respectively) and some PGF2 alpha and PGE2 (8-8%). However, in the presence of reduced glutathione (GSH), PGE2 became the main product (81%) (TxB2, 15%; PGF2 alpha, 2%; and 6-keto-PGF1 alpha, 2%). Half-maximal stimulation of PGE2 synthesis occurred at 46 microM GSH. The GSH concentration of tissue samples was found to be 110 +/- 30 microM. We conclude that human first trimester decidua cells possess the key enzymes of prostaglandin and thromboxane synthesis. Apparently, the production of these compounds is controlled by a specific mechanism in the tissue, which keeps PGE and prostacyclin synthesis in a reversibly suppressed state, whereas the formation of thromboxane is relatively stimulated.

6-Ketoprostaglandin F1 alpha↗
PubMed1984

The use of subcutaneous tissue flaps in the repair of soft tissue defects of the forearm and hand: an experimental and clinical study of a new technique.

This paper records our experience with a new technique of providing cover for soft tissue defects of the upper extremity using flaps consisting of subcutaneous tissue only and relying on the arterial anastomotic network of this tissue layer to sustain its vascularisation. The experimental basis of this technique is described in detail and two illustrations of the clinical use of this technique are given. The main advantages of this type of flap are its ready availability from the local tissues, its elasticity, the absence of functional and aesthetic disturbance at the donor site and the preservation of the natural contour of the limb.

Adolescent↗
PubMed1980

Connective tissue activation. XVII. Radioimmunoassay of a human platelet derived connective tissue activating peptide (CTAP-III) and specificities of anti-CTAP-III sera.

The platelet-derived connective tissue activating peptide (CTAP-III) has been shown to be an important factor stimulating the metabolism and proliferation of human connective tissue cell strains, including synovial tissue cells. The quantities of CTAP-III affecting the cellular changes and the amounts of various biologic fluids and tissues are small. The objectives of this study were to develop a radioimmunoassay (RIA) for CTAP-III and to ascertain the specificities of the anti-CTAP-III sera reagents. The antisera were shown not to cross-react with a number of polypeptide hormones. However, two other platelet proteins, beta-thromboglobulin and low affinity platelet factor-4, competed equally as well as CTAP-III for anti-CTAP-III antibodies in the RIA system. Thus, the three platelet proteins are similar or identical with respect to those portions of the molecules constituting the reactive antigenic determinants. The levels of material in normal human platelet-free plasma that inhibited anti-CTAP-III--125I-CTAP-III complex formation were determined to be 34 +/- 13 (S.D.) ng/ml.

Animals↗
PubMed1984

Proteolytic activation of tissue plasminogen activator by plasma and tissue enzymes.

Tissue kallikrein and factor Xa were found to activate tissue plasminogen activator (t-PA) at a rate comparable with that of plasmin. During the activation reaction, the single-chain molecule was converted into a two-chain form. A slight t-PA activating activity was also found in plasma kallikrein. Other activated coagulation factors, factor XIIa, factor XIa, factor IXa, factor VIIa, thrombin and activated protein C had no effect on t-PA activation. t-PA was also activated by a tissue kallikrein-like enzyme that was isolated from the culture medium of melanoma cells. These results indicate that tissue kallikrein and factor Xa may participate in the extrinsic pathway of human fibrinolysis.

Animals↗
PubMed1987

Determination of testosterone and its tissue metabolites (DHT and 3 alpha-diol) in human plasma and prostatic tissue by isotopic dilution mass spectrometry.

5 alpha-Dihydrotestosterone has been widely measured in human prostatic tissue using RIA since it is involved in the pathogenesis of human prostatic hyperplasia and seems to be the best index for the follow-up of patients affected by prostatic cancer under endocrine treatment. A GC-MS method for the simultaneous determination of testosterone (T), 5 alpha-dihydrotestosterone (DHT) and 5 alpha-androstan-3 alpha, 17 beta-diol (3 alpha-diol) in prostatic tissue based on the isotopic dilution technique was developed. Tri-deuterated internal standards of each compound were previously synthetized in our laboratory. After extraction and purification on Sep-Pak C18 and Sephadex LH-20, T and its metabolites were measured as heptafluorobutyric ester (HFB) derivatives. Quantitative analysis was performed on a VG 7070 EQ mass spectromer equipped with a fused silica capillary column using the Selected Ion Monitoring technique. Steroid values (mean +/- SD; ng/g tissue) found in nine human hypertrophic prostates were: T: 0.71 +/- 0.43; DHT: 4.46 +/- 1.41; 3 alpha-diol: 0.34 +/- 0.23. Preliminary results obtained from the detection of the three androgens in human prostatic hyperplasia treated for 3 months with GnRH before surgery seem to indicate that DHT concentration decreases more than 10 times. Values obtained (n = 1; ng/g tissue) were: T: 0.194; DHT: 0.255; 3 alpha-diol: 0.015.

Androstenediol↗
PubMed1986

Plasma and tissue levels of some lanthanide elements in malignant and non-malignant human tissues.

Lanthanum (La) levels in plasma, in erythrocyte hemolysate and in tissue from healthy subjects and patients with laryngeal carcinoma were determined by neutron activation analysis. Plasma lanthanum levels were significantly higher in laryngeal carcinomas than in either healthy controls or in subjects suffering from localized inflammation (e.g. epicondylitis of the elbow) (p less than 0.001). The mean La concentration in malignant tissue samples was 57.5 +/- 7.2 ng g-1; the corresponding level in normal adjacent tissue from the same organ was 94.6 +/- 12.0 ng g-1. This 61% decrease in the concentration of La in malignant tissues was highly significant (p less than 0.001). In patients with laryngeal carcinoma we did not observe any detectable level of lanthanum in erythrocyte hemolysate; the mean La erythrocyte hemolysate level in healthy controls and in patients suffering from localized inflammatory condition was 14.3 and 33.2 ng ml-1, respectively. Further studies are in progress to evaluate whether or not this element can serve as a marker for diagnosis or prognosis in cancer.

Adult↗
PubMed1994

Krypton fluoride excimer laser ablation of tooth tissues: precision tissue machining.

A variety of lasers using different wavelengths have been used to remove dental hard tissue. The infrared lasers produce their effects photothermally whereas ultraviolet excimer lasers remove tissue in a controlled and precise manner by photoablation. This study investigates the use of 248 nm laser radiation in the precision removal of both enamel and dentine using diffraction limited ultraviolet optics. The data showed that enamel and dentine were machined to a high level of precision (1-2 micron tolerances). The rate of removal was greater in dentine than enamel at a range of energy densities between 1.15 and 2.2 J/cm2. The method of removal of both tissues appears to be by the preferential ablation of the organic phases of each, exposing the anatomical details of their structure. An explanation of the possible method of ablation is proposed for these tissues.

Dental Enamel↗
PubMed1993

Algorithm for semi-automatic sorting of objects to specified tissue domains. An aid for co-ordinating morphometric data with identified tissue components.

A personal computer-based technique was developed that reduces the extent of human efforts in obtaining data, like numerical density of profiles on area, describing the distribution of specific features of histological sections, e.g., density of synaptic profiles or of histochemical reaction products in specified tissue compartments. The procedure consists of (i) marking the objects to be counted, (ii) recording the borderlines of (reference) tissue domains of interest, and (iii) allocating the marked objects to the corresponding domains automatically. This automatic sorting of objects into defined tissue domains is achieved by an algorithm operating on two sets of coordinates: (i) coordinates of points that constitute the boundary of tissue domains (perimeter points) and (ii) coordinates of points marking the particular objects to be sorted. The principle of the sorting calculation is to construct 'segments' of the loop by lines parallel to the ordinate which pass through neighbouring perimeter points. The 'items' to be sorted are classified by the sign of marker flags allocated to each point depending on which side of the perimeter segment they are located. Segmentation and classification procedures are sequentially repeated along the entire perimeter of each domain specified by the operator which may result during the procedure in multiple changes of the sign of the flags. The internal or external location of each item finally is represented by the last sign of its flag. Objects, allocated to domains can be counted and processed further for numerical density determination.

Algorithms↗
PubMed1995

Regulation of valine catabolism in canine tissues: tissue distributions of branched-chain aminotransferase and 2-oxo acid dehydrogenase complex, methacrylyl-CoA hydratase and 3-hydroxyisobutyryl-CoA hydrolase.

To clarify the valine catabolism, the activities of principal enzymes in its catabolic pathway, branched-chain aminotransferase, branched-chain 2-oxo acid dehydrogenase complex, methacrylyl-CoA hydratase and 3-hydroxyisobutyryl-CoA hydrolase, were measured using canine tissues. After killing of beagle dogs, tissues (liver, pancreas, kidney, heart, skeletal muscle and mucosae of digestive organs such as stomach, small intestine and colon) were removed and immediately frozen. Branched-chain aminotransferase activity in liver was the lowest among the tissues measured. In contrast, the activities of branched-chain 2-oxo acid dehydrogenase complex in liver as well as in kidney were relatively high and the enzyme complex activities were markedly low in small intestine and skeletal muscle. The activities of methacrylyl-CoA hydratase and 3-hydroxyisobutyryl-CoA hydrolase were relatively high in all tissues, suggesting that a cytotoxic intermediate, methacrylyl-CoA, is immediately degraded to non-toxic compounds, 3-hydroxyisobutyrate and free CoA. These findings suggest that the consumption of branched-chain amino acids in the absorption site (small intestine) is suppressed in order to supply them to the whole body, in particular to skeletal muscle and that skeletal muscle might act as a storage of gluconeogenic amino acids. The high capacity to dispose methacrylyl-CoA produced in the valine catabolism is suggested to play an important role in protecting cells against the toxic effects of methacrylyl-CoA.

3-Methyl-2-Oxobutanoate Dehydrogenase (Lipoamide)↗