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PubMed2004

Tissue-specific effect of refeeding after short- and long-term caloric restriction on malic enzyme gene expression in rat tissues.

Restricting food intake to a level below that consumed voluntarily (85%, 70% and 50% of the ad libitum energy intake for 3 or 30 days) and re-feeding ad libitum for 48 h results in an increase of malic enzyme (ME) gene expression in rat white adipose tissue. The increase of ME gene expression was much more pronounced in rats maintained on restricted diet for 30 days than for 3 days. The changes in ME gene expression resembled the changes in the content of SREBP-1 in white adipose tissue. A similar increase of serum insulin concentration was observed in all groups at different degrees of caloric restriction and refed ad libitum for 48 h. Caloric restriction and refeeding caused on increase of ME activity also in brown adipose tissue (BAT) and liver. However, in liver a significant increase of ME activity was found only in rats maintained on the restricted diet for 30 days. No significant changes after caloric restriction and refeeding were found in heart, skeletal muscle, kidney cortex, and brain. These data indicate that the increase of ME gene expression after caloric restriction/refeeding occurs only in lipogenic tissues. Thus, one can conclude that caloric restriction/refeeding increases the enzymatic capacity for fatty acid biosynthesis.

Adipose Tissue↗
PubMed1978

Implanted tissue-cages: a critical evaluation of their relevance in measuring tissue concentrations of antibiotics.

In several species of laboratory animals, the concurrent serum and tissue-cage fluid levels of several antibiotics after a single parenteral dose have markedly different profiles. New work has shown that these differences are mainly due to the relatively impermeable granulomatous sheath which develops around the implanted tissue chambers. The concentrations of an antibiotic in tissue-cage fluid are therefore not representative of its concentration in "interstitial fluid" or extravascular fluid in general. Tissue-cage levels are probably more representative of antibiotic levels to be found inside abscesses, in chronic disease situations, or relatively avascular sites in the body.

Animals↗
PubMed1994

Tissue inhibitor of metalloproteinases-3 (TIMP-3) is an extracellular matrix-associated protein with a distinctive pattern of expression in mouse cells and tissues.

We have isolated cDNA clones corresponding to a novel mouse metalloproteinase inhibitor. Five overlapping cDNA clones contain most of the information for a prominent 4.5-kilobase transcript that was detected in RNA from mouse fibroblasts and adult tissues. Sequence analysis revealed an open reading frame (ORF) for a protein of 212 amino acids that is 80% identical to chicken inhibitor of metalloproteinases-3 (ChIMP-3). The 3'-untranslated sequence also showed remarkable conservation with the chicken gene. The ORF directed the expression of a 24-kDa protein in COS-1 cells that localized to the extracellular matrix (ECM). On the basis of these similarities we propose to identify the new gene as murine tissue inhibitor of metalloproteinases-3 (TIMP-3). Mouse C3H 10T1/2 fibroblasts produced a 24-kDa metalloproteinase inhibitor that also localized to the ECM and was recognized by a polyclonal antibody to ChIMP-3. Like TIMP-1, TIMP-3 was highly inducible in mouse C3H 10T1/2 fibroblasts by phorbol ester (PMA), epidermal growth factor (EGF), and transforming growth factor-beta 1, but nuclear run-on assays showed that the on/off transcription kinetics were faster for TIMP-3 than TIMP-1. A major difference in vitro was the stimulation of expression of TIMP-3 by dexamethasone which inhibits EGF- and PMA-induced TIMP-1 transcription. Also, TIMP-3 showed a distinctive pattern of expression in adult tissues with abundant transcripts detected in kidney, lung, and brain but only low levels detected in bone, a prominent location of TIMP-1 transcripts. We propose that TIMP-3 functions in a tissue-specific fashion as part of an acute response to remodeling stimuli.

Amino Acid Sequence↗
PubMed2000

Laser-tissue interaction with a continuous wave 3-mcm fibre laser: preliminary studies with soft tissue.

BACKGROUND AND OBJECTIVE: Lasers operating at wavelengths in the mid-infrared region have become increasingly popular for applications in areas of surgery and medicine. Advances in fibre laser technology have introduced a highly efficient, compact, diode-pumped source operating at around the 3-mcm wavelength. This study examines the effects of this recently developed laser on soft biological tissue. STUDY DESIGN/MATERIALS AND METHODS: Chicken breast and liver tissue samples were exposed to 800 mW continuous wave laser power, at a wavelength of 2.71 mcm, with incident spot sizes of around 150 mcm. Samples were inspected grossly immediately after laser irradiation and also prepared for histologic processing. RESULTS: After irradiation, visual assessment of changes at sample surfaces indicated a region of thermally affected tissue surrounding the ablation crater. This region was observed to grow in size to around 1.0 mm in diameter after 3 seconds of laser exposure at 800 mW. An ablation velocity of 0.80 mm.s(-1) was determined in chicken breast for the same incident laser parameters. Analysis of samples irradiated at 800 mW and processed for histology revealed minimal damage at hole boundaries and no signs of char formation, providing incident exposure times were restricted to below around 0. 5 seconds. CONCLUSION: This fibre laser source has demonstrated its potential to fulfil medical applications, enabling accurate, precise tissue removal to proceed at a rapid ablation rate. The efficiency and small size of the laser are attractive features.

Animals↗
PubMed2000

High-performance liquid chromatographic assay for the determination of novel triazole antifungal agents in tissue. Application to tissue distribution studies.

A simple and rugged reversed-phase high-performance liquid chromatographic method with ultraviolet absorbance detection at 263 nm was developed and validated for the analysis of novel triazole antifungal agents SYN-2869 and its derivatives in tissues. The method involved homogenization with 0.01 M phosphate buffer (pH 7.8) for lung, brain and spleen tissues. The liver and kidneys were homogenized with acetonitrile:acetone (1:1). The plasma proteins were precipitated with ice-cold acetonitrile and supernatent was evaporated to dryness. The reconstituted samples were injected onto an HPLC system. SYN-2869 was separated from the matrix components on a symmetry C(18) column using a aqueous mobile phase of acetonitrile and water with a flow rate of 1 mL/min. A step gradient of 40-80% acetonitrile eluted SYN-2869 and the internal standard (SYN-2506). The linear range was 0.5-10 microgram/g (r(2) > 0.99). The limit of quantitation was 0.5 microgram/g. The inter-day precision and accuracy for SYN 2869 standard concentration were from 2.6 to 7.4% and from -1.56 to +3.29%, respectively. The method was applied to tissue samples collected from single intravenous administration to mice to evaluate the distribution of these novel antifungal agents to different tissues.

Animals↗
PubMed1989

Tissue localization of photosensitizers and the mechanism of photodynamic tissue destruction.

This paper outlines our present knowledge of photosensitizer tissue distribution, derived from preclinical animal studies, and relates it to the observed biological response to photodynamic therapy (PDT). Emphasis is placed on porphyrins (haematoporphyrin derivative (HpD), Photofrin II) and phthalocyanines (aluminum phthalocyanine sulphonate AlPcS). In mice, both groups of sensitizers show multiphasic plasma clearance kinetics with an initial rapid decline followed by further slow reduction. Residual amounts of Photofrin II are detectable 75 days after injection. Drug elimination occurs through urine and faeces, but faecal elimination predominates for Photofrin II. Circulating sensitizer greatly influences the mouse ear-swelling response, but not the foot response. Tumours and normal skin can be destroyed by vascular damage, if illumination occurs at times of maximal plasma sensitizer concentration, with no detectable sensitizer accumulation in tumour cells. Organ retention for both photosensitizer groups is similar and persistent. Organs rich in reticuloendothelial elements (liver, kidney, spleen) accumulate and retain the highest levels, skin and muscle the lowest, while normal brain tissue excludes sensitizer. The adrenal and pancreatic glands, as well as urinary bladder, also retain high amounts of Photofrin II. Tumour/skin ratios of 1 to 3:1 and 2 to 7:1 have been reported for porphyrins and sulphonated phthalocyanines respectively. Tissue destruction upon light exposure is not always correlated with photosensitizer levels, as is exemplified by liver and pancreas. Stromal sensitizer localization usually predominates in tumour and normal tissue, and often determines tumour response. Certain compounds, such as monosulphonated tetraphenylporphyrin and AlPcS, may favour parenchymal localization. The formed blood elements remain free of photosensitizer, while mast cells and macrophages accumulate especially large amounts and, upon illumination, release an array of vasoactive inflammatory and immune mediators.

Animals↗
PubMed1984

Connective tissue activation. XXVIII. A connective tissue activating peptide from human urine.

A protein factor in human urine which has the ability to activate connective tissue cells has been identified and partially purified; it appears to be different from epidermal growth factor and IgG. This urinary connective tissue activating factor (CTAP-U) is nondialyzable, labile to protease, stable to thiols, heat, and acid, and has an acidic isoelectric point. Purified preparations of CTAP-U have biologic activities that cause human connective tissue cells to synthesize incremental amounts of 14C-hyaluronic acid, 35S-proteoglycans, and 3H-DNA in vitro. The cell spectrum responsive to this substance includes human synovial cells, human chondrocytes, and skin fibroblasts. CTAP-U does not react with antisera to connective tissue activating peptide-III or to antibodies against IgG or its Fc and Fab fragments. Furthermore, CTAP-U does not cross-react in a radioreceptor assay for insulin, basic somatomedin, or epidermal growth factor-urogastrone. Utilizing standardized isolation conditions, CTAP-U preparations with these properties have been isolated from the urine of 6 normal individuals.

Cartilage↗
PubMed1986

A monoclonal antibody reacting with endothelial cells of budding vessels in tumors and inflammatory tissues, and non-reactive with normal adult tissues.

This report describes a monoclonal antibody (MAb) generated by immunization of mice with cell suspensions of capillary-rich fragments of mammary carcinomas. The antibody (EN 7/44) belongs to the IgM class and detects a 30.5 kDa antigen which is found in the cytoplasm of human placental and umbilical vein-endothelial cells (HUVEC) and on the surface of tumor endothelium. Using indirect immunofluorescence and immunoperoxidase techniques, we did not find the MAb in peripheral blood cells or in any human cell lines tested, nor in endothelial cells from normal, nonproliferating adult tissues. Positively staining endothelium was found in the placenta, the umbilical vein and in proliferating normal tissues (intestine). Positive endothelial cells were found in acute inflammatory reactions and in tumors. In the latter, the strongest reactions were seen in newly formed budding capillaries, which were identified by their reactivity with Ulex europaeus I-lectin and antibodies against F VIII-RAG. In tumor tissues, large vessels could be positively stained with the EN 7/44 antigen, in contrast to inflammatory tissues. It is concluded that endothelial cells at the tip of a budding capillary express distinct phenotypic characteristics.

Adult↗
PubMed1991

Tissue and urokinase plasminogen activators in bone tissue and their regulation by parathyroid hormone.

The identification of the plasminogen activator (PA) types present in bone and the regulation of their activity by parathyroid hormone (PTH) were investigated in cultures of fetal mouse calvariae with the use of either a chromogenic substrate or a zymographic assay. PA was detected essentially in the tissue extracts of the explanted bones, with only 1-2% of the total activity released in the surrounding culture media. From their electrophoretic behavior compared to PAs of other mouse tissues and from their response to a specific antibody raised against the tissue type PA (tPA), two major molecular species, of 70 and 48 kD were identified as tPA and urokinase (uPA), respectively, a third minor species of 105 kD being likely to correspond to complexes between tPA and an inhibitor; the culture fluids, moreover, contained enzymatically active degradation products of uPA of 42 and 29 kD. The PA activity of the bone extracts was only minimally affected by the addition of fibrinogen fragments to the chromogenic assays. PTH induced bone resorption and stimulated in parallel the accumulation of PA in the tissue; other bone-resorbing agents, 1,25-dihydroxyvitamin D3 and prostaglandin E2, had similar effects. Densitometric scanning of the zymograms of the bone extracts indicated that PTH stimulated only the production of tPA and had no effect on that of uPA. However, PTH also enhanced the release of uPA (both the 48 kD and the 29 kD forms) from the bones into the media. Although inhibiting bone resorption, calcitonin had no effect on the PTH-induced accumulation of PA in bone or on the release of tPA, but it prevented the PTH-induced accumulation of 29 kD uPA in the culture fluids. Thus these studies support the view that tPA and possibly also uPA may have a role in the physiology of bone; the nature of this role remains to be elucidated, however.

Antibodies↗
PubMed2004

The transillumination possibility of imidazole-osmium postfixed muscle tissue and its consequences for the handling of muscle tissue samples.

The osmium postfixation of tissue leads to good results for transmission electron microscopy, but also produces completely blackened tissue samples that do not allow the recognition of internal structures. With imidazole-osmium postfixation, one achieves comparable results in high electron microscopic resolution as with routine osmium postfixation. But the tissue samples are not blackened and can, therefore, be transilluminated with point light sources. The new postfixation technique makes it possible to recognize histological details such as vessels, nerve fibers, and the cross-banding pattern in an untrimmed block. This makes it possible to screen-embedded tissue samples for appropriate ultrastructural processing.

Animals↗
PubMed1986

Single pass mean residence time in peripheral tissues: a distribution parameter intrinsic to the tissue affinity of a drug.

The single pass mean residence time in peripheral tissues, tp1, is a characteristic constant of linear pharmacokinetic systems and nonlinear systems with linear distribution kinetics. It is descriptive of distribution kinetics in such systems and is not dependent on elimination kinetics as are other related parameters, e.g., mean residence time in peripheral tissues, tp. Equations are derived which permit estimation of tp1 from experimental data for systems in which no peripheral elimination occurs. The type of data required are systemic drug levels resulting from iv administration. The probability density function for single pass residence time in peripheral tissues is derived. It is shown that tp1 is related to the amount of drug in the peripheral tissues at steady state according to (Ap)ss = CLdCsstp1, where CLd is the distribution clearance, and Css is the steady-state systemic drug level. Values of tp1 are presented for several drugs.

Humans↗
PubMed1997

In vitro hydration kinetics of recent post-mortem tissue versus pre-dried corneal stromal tissue.

Both recent post-mortem and pre-dried corneal tissue has been used for laboratory studies of stromal swelling, but it has yet to be defined whether the same hydration (H value, mg H2O/mg dry mass) is obtained after extended re-hydration. Fresh or pre-dried pieces (8x8 mm squares) of ovine stromas were immersed in 1% NaCl for 24 hr at 37 degrees C, with the wet mass assessed regularly. Pre-drying was achieved in air for 7 days (with sulphuric acid, CaSO4 or silica gel as desiccants), or in an oven for 24 hr at 60, 70 or 80 degrees C. Fresh stroma preparations (</=2 hr post-mortem) had initial H values of 3.1, which increased to 27.8 after 24 hr in saline. After pre-drying over sulphuric acid, CaSO4 or silica gel, the H values after 24 hr in saline were 19.1, 13.1 and 7.3 respectively (all statistically different from fresh tissue (P<0.01). Following oven drying at 60, 70, and 80 degrees C, final H values of 8.5, 6.6, and 5.0 were obtained after 24 hr in saline. Recent post-mortem material showed sustained swelling over at least 24 hr. For pre-dried tissue, initial rates of hydration change over 1 hr were higher, but subsequent rates were substantially less after 2 hr. These studies indicate that fresh tissue should be used in studies concerning the swelling properties of the corneal stroma.

Animals↗
PubMed1994

Immunohistochemical detection of tissue factor (TF) on paraffin sections of routinely fixed human tissue.

Tissue factor (TF), a 47 kDa transmembrane glycoprotein, is the essential receptor and cofactor for factor VII/VIIa. Its distribution in normal tissues and in tumours has been recently investigated immunohistochemically with monoclonal and polyclonal anti-TF antibodies in frozen sections. The cardinal problem of this technique is the difficulty of determining exactly the localization of the reaction product at least in certain tissues. Here, we demonstrate a method using monoclonal anti-TF antibodies to detect TF in routinely fixed, microwaved, paraffin-embedded tissues. Generally, there were no fundamental differences in TF distribution in frozen and paraffin-embedded material. However, in most cases, the paraffin sections allow a better cellular localization of TF. For example, the staining pattern for TF in both kinds of sections is identical in kidney, brain and skin. The paraffin-embedded material, however, clearly shows that TF expression is restricted to the parietal and the visceral epithelia of Bowman's capsule of glomeruli in the kidney, and to astrocytes and their processes in the brain. TF reactivity in the skin is revealed to be cell membrane-bound; in cardiomyocytes TF shows an exclusively sarcolemmal localization. The immunohistological detection of TF in paraffin sections is a powerful tool for systematic studies on the possible role of TF in the context of physiological and pathological studies.

Antibodies, Monoclonal↗
PubMed1992

Does malignant transformation of benign soft-tissue tumours occur? A clinicomorphological study of ten initially misdiagnosed soft-tissue sarcomas.

Ten soft-tissue sarcomas out of a consecutive series of 201 neoplasms are described, in which the clinical histories were suggestive of malignant transformation of a benign lesion excised from the same location 2-97 months before. Each of the 10 preceding soft-tissue neoplasms was reviewed histologically and reclassified as either highly (n = 8) or moderately differentiated (n = 2) sarcomas. Irrespective of the primary treatment, these initially misdiagnosed tumours showed an overall better prognosis than the whole group of soft-tissue sarcomas (5- and 10-year survival rates 76% versus 44%, and 52% versus 30% respectively). Their clinical course was, however, characterized by up to 6 (mean 2.9) local recurrences. From the total series of 201 tumours the authors conclude that soft-tissue sarcomas other than malignant schwannomas in the setting of von Recklinghausen's disease only exceptionally, if ever, arise from benign precursors.

Adult↗
PubMed1983

Systematic protocol for the accumulation of fatty acid data from multiple tissue samples: tissue handling, lipid extraction and class separation, and capillary gas chromatographic analysis.

A systematic procedure was developed for detailed fatty acid profiling of both neutral and polar lipid fractions isolated from hundreds of related bovine muscle and adipose tissue samples. A regimen was established for a nonbiased handling of tissue samples, which included their handling in a predetermined random order. Lipid class separation was accomplished concomitantly during the extraction of the tissues by a selective dry column method, which allowed a detailed analysis of minor but important polyunsaturated fatty acids associated with the polar fraction. Neutral lipids were derivatized to fatty acid methyl esters (FAME) by a literature procedure. However, to protect against lysis of plasmalogens in the polar fraction, a modified nonacidic esterification procedure was developed. FAME profiles were obtained on a programmable high resolution capillary gas chromatograph (GC). Run programs for unattended GC operation and data storage are described. By this overall procedure, the quantitation and peak identification were obtained for major and minor fatty acid constituents from bovine tissue in a manner that prepares for valid statistical interpretation of the resulting data.

Adipose Tissue↗
PubMed1999

Expression of mRNA encoding tissue-nonspecific alkaline phosphatase in human dental tissues.

Tissue-nonspecific-type alkaline phosphatase (TNSALP) is found in the bone, liver, kidney, and other tissues, and its gene consists of 12 exons with the coding sequence beginning in the second exon. Recently, a noncoding first exon was identified in the liver message (liver type) which differed from that of the previously known osteoblast-derived cDNA sequence (bone type). Although these two mRNAs produce an identical protein, they have different promoter regions. It is known that ALPs in dental pulp and periodontal ligament are classified into TNSALP by their enzymatic and immunological properties, but little is known about the expression of ALP mRNAs and the transcriptional mechanisms. In order to examine the expression of their mRNA type, specific oligonucleotide primers corresponding to two types of mRNAs of human TNSALP were designed and amplified by reverse transcription-polymerase chain reaction (RT-PCR). It was found that bone-type mRNA was expressed in the human dental tissues such as dental pulp, periodontal ligament, and dental sac, whereas liver-type mRNA was not expressed. Thus, it was concluded that the human dental tissues express the bone-type isozymes and are regulated by the same transcriptional mechanism as in the bone.

Alkaline Phosphatase↗
PubMed2001

Tissue-specific cadmium accumulation, metallothionein induction, and tissue zinc and copper levels during chronic sublethal cadmium exposure in juvenile rainbow trout.

Juvenile rainbow trout, on 3% of body weight daily ration, were exposed to 0 (control) or 3 microg/L Cd (as Cd(NO3)2*4H2O) in moderately hard (140 mg/L as CaCO3), alkaline (95 mg/L as CaCO3, pH 8.0) water for 30 days. Particular attention focused on Cd burden in tissues (gills, liver, kidney, and whole body) and induction of metallothionein (MT) in gills, liver, and kidney during chronic Cd exposure. Mortality in Cd-exposed fish was minimal ( approximately 10%), and no growth effects occurred over the 30-day exposure. Cd accumulated in a time-dependent fashion to 9 times (gills), 3 times (liver), 20 times (kidney), 2 times (carcass), and 2 times (whole body) control levels by 30 days; absolute concentrations were in the order kidney > gill > liver > whole body > carcass. Tissue (gills, liver, and kidney) Zn and Cu burdens were not altered by chronic exposure to 3 microg/L Cd. MT concentrations in all tissues increased over the 30 days of Cd exposure, but the increases were much less than those of Cd on a molar binding site basis. Absolute MT concentrations were in the order liver > kidney > gill, but relative increases were greatest in kidney (fourfold), followed by gills (twofold) and liver (1.3-fold). MT levels were sufficient to bind all Cd in gill, liver, and kidney under control conditions, and after chronic Cd exposure remained sufficient in liver and kidney, but not in gills. Total metal levels (Cd + Zn + Cu) greatly exceeded MT binding capacity in all tissues under all conditions.

Animals↗