Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Tissues”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 631 records · Page 35Linked to original sources

Human esophageal cancer is distinguished from adjacent esophageal tissue by tissue cysteine concentrations.

Recent studies have suggested that cysteine, in addition to glutathione, may play a role in the genesis, pathobiology, and treatment response of rodent and human cancers. We examined the relative concentrations of cysteine and glutathione in human esophageal cancer and adjacent, minimally involved esophageal tissue. Small biopsies from tumors and adjacent esophageal tissues were placed into cold acid to allow extraction of low-molecular-mass compounds and simultaneous precipitation of macromolecules. Supernatants were analyzed by high-performance liquid chromatography with electrochemical detection for thiol content. While there was no statistically significant difference between the glutathione content of tumor versus adjacent tissue (2.2 mM vs 2.1 mM, respectively), tumor tissue had significantly higher levels of cysteine than adjacent tissue (0.21 mM vs 0.13 mM, respectively). In conclusion, cysteine content distinguishes tumor from adjacent more normal tissue.

Adenocarcinoma↗

Progress of National Multi-tissue Bank in Uruguay in the International Atomic Energy Agency (IAEA) Tissue Banking Programme.

The transplant law of 1971 based on informed consent, allows people to register their willingness to be a donor upon death. Since 1978 the governmental Institution, the National Bank of Organs and Tissues (BNOT), have been regulated the organ and tissue donation. Important progress was implemented in the BNOT and specially in the National Multi-tissue Bank (NMTB). Since 2001 with the participation in the IAEA Tissue Banking Programme, Quality System Management has been implemented in the NMTB. New bio-production for radiosterilized tissues for the first time and improved procedures were carried out. As a result an increased production of high-quality tissues was obtained and distributed for clinical use.

Journal Article↗

Integrated backscatter during harmonic and fundamental frequency imaging--effect of depth, mechanical index, and tissue anisotropy: implications for myocardial tissue characterization.

OBJECTIVE: To explore the potential advantages of tissue harmonic imaging (THI) versus fundamental frequency imaging (FFI) when applied to tissue characterization. METHODS: A Philips Medical Systems Sonos 5500 echocardiograph equipped with a broadband transducer (S4) and an on-line quantitative analysis software package (Acoustic Densitometry) was used for imaging. The effect of mechanical index (MI), imaging depth, and anisotropy on relative backscatter amplitude was evaluated. RESULTS: This study demonstrated that imaging with tissue harmonics generated relatively greater backscatter values at clinically relevant imaging depths and instrument settings referenced to FFI. This effect was dependent on MI setting. A direct relationship between backscatter amplitude and MI was demonstrated. Additionally, tissue anisotropy had similar effects on integrated backscatter amplitude during both THI and FFI. However, relative backscatter values at each fiber orientation are greater during THI at similar instrument settings when referenced to FFI. CONCLUSION: Tissue harmonic imaging may offer advantages over FFI for myocardial tissue characterization.

Animals↗

Resonance sensor measurements of stiffness variations in prostate tissue in vitro--a weighted tissue proportion model.

Prostate cancer is the most common type of cancer in men in Europe and the US. The methods to detect prostate cancer are still precarious and new techniques are needed. A piezoelectric transducer element in a feedback system is set to vibrate with its resonance frequency. When the sensor element contacts an object a change in the resonance frequency is observed, and this feature has been utilized in sensor systems to describe physical properties of different objects. For medical applications it has been used to measure stiffness variations due to various patho-physiological conditions. In this study the sensor's ability to measure the stiffness of prostate tissue, from two excised prostatectomy specimens in vitro, was analysed. The specimens were also subjected to morphometric measurements, and the sensor parameter was compared with the morphology of the tissue with linear regression. In the probe impression interval 0.5-1.7 mm, the maximum R(2) > or = 0.60 (p < 0.05, n = 75). An increase in the proportion of prostate stones (corpora amylacea), stroma, or cancer in relation to healthy glandular tissue increased the measured stiffness. Cancer and stroma had the greatest effect on the measured stiffness. The deeper the sensor was pressed, the greater, i.e., deeper, volume it sensed. Tissue sections deeper in the tissue were assigned a lower mathematical weighting than sections closer to the sensor probe. It is concluded that cancer increases the measured stiffness as compared with healthy glandular tissue, but areas with predominantly stroma or many stones could be more difficult to differ from cancer.

Aged↗

Effects of dietary calcium on blood and tissue lipids, tissue phospholipids, calcium and magnesium levels in rabbits fed diets containing beef tallow.

Levels of lipids, calcium and magnesium in blood and tissue were examined in rabbits to determine the effects of 20% beef tallow diets containing three levels of calcium, less than 0.02, 0.8 or 1.6%. In plasma, the calcium-deficient (less than 0.02%) diet contributed to elevated cholesterol and phospholipid, but had no effect on triglyceride levels. Plasma calcium decreased in the calcium-deficient group and plasma magnesium decreased in the high-calcium (1.6%) group of rabbits. Lipid levels of some tissues varied with the level of dietary calcium. Cholesterol, total phospholipid, sphingomyelin and phosphatidylethanolamine were generally elevated in livers of calcium-deficient rabbits, but the individual phospholipids were decreased in skeletal muscle. Lungs of the calcium-deficient group also had lower phospholipid levels than the high-calcium group. Liver, kidneys, brain and adipose tissue triglyceride levels were highest in the high-calcium group. The calcium level of skeletal muscle was lower in the calcium-deficient group than in the high-calcium group. Calcium in brain and adipose tissue were highest in the calcium-deficient group. Except for adipose tissue, magnesium levels of the tissues studied were not affected by dietary calcium.

Animals↗

Tissue-dependent isoforms of mammalian Fox-1 homologs are associated with tissue-specific splicing activities.

An intronic hexanucleotide UGCAUG has been shown to play a critical role in the regulation of tissue-specific alternative splicing of pre-mRNAs in a wide range of tissues. Vertebrate Fox-1 has been shown to bind to this element, in a highly sequence-specific manner, through its RNA recognition motif (RRM). In mammals, there are at least two Fox-1-related genes, ataxin-2 binding protein 1 (A2BP1)/Fox-1 and Fxh/Rbm9, which encode an identical RRM. Here, we demonstrate that both mouse Fxh and A2BP1 transcripts undergo tissue-specific alternative splicing, generating protein isoforms specific to brain and muscle. These tissue-specific isoforms are characterized for their abilities to regulate neural cell-specific alternative splicing of a cassette exon, N30, in the non-muscle myosin heavy chain II-B pre-mRNA, previously shown to be regulated through an intronic distal downstream enhancer (IDDE). All Fxh and A2BP1 isoforms with the RRM are capable of binding to the IDDE in vitro through the UGCAUG elements. Each isoform, however, shows quantitative differences in splicing activity and nuclear distribution in transfected cells. All Fxh isoforms and a brain isoform of A2BP1 show a predominant nuclear localization. Brain isoforms of both Fxh and A2BP1 promote N30 splicing much more efficiently than do the muscle-specific isoforms. Skeletal muscles express additional isoforms that lack a part of the RRM. These isoforms are incapable of activating neural cell-specific splicing and, moreover, can inhibit UGCAUG-dependent N30 splicing. These findings suggest that tissue-specific isoforms of Fxh and A2BP1 play an important role in determining tissue specificity of UGCAUG-mediated alternative splicing.

Alternative Splicing↗

Inter-Tissue Correlations in Organ Fragments: Organogenetic Capacity of Tissues Excised from Stem Segments of Torenia fournieri Lind Cultured Separately in Vitro.

In order to study the effect of inter-tissue correlations on the organogenetic capacities of various tissues of stem segments of Torenia fournieri Lind, different types of explants were excised and grown separately: epidermis, subepidermal parenchyma, epidermis plus subepidermal parenchyma but devoid of vascular tissue and stem segments devoid of epidermis.The epidermis, normally capable of bud formation in the context of a stem segment, dies if grown in culture alone; however, it can form buds after callus formation if, after excision, it is replaced on the original stem segment. Subepidermal parenchyma, normally mitotically inactive in the stem segment, forms roots when grown alone and buds and roots when grown with the epidermis. A stem segment devoid of epidermis forms only roots. The histological study showed that, in explants composed of epidermal and a few subepidermal parenchyma layers, buds can arise exclusively from the epidermis or from both epidermal and subepidermal cells, whereas roots are exclusively formed by parenchyma tissue.The break in correlations among tissues by the culture of each tissue separately seems to "liberate" masked capacities in certain tissues and to repress the expression of capacities in others.

Journal Article↗

Expression of bone marrow stromal cell specific antigen during murine development: its expression in embryonic hematopoietic tissues as well as in other developing tissues.

Monoclonal antibody R4-A9 demonstrated specificity for a cell surface antigen of stromal cells in murine bone marrow and spleen. In order to identify patterns of expression that may elucidate the potential role of R4-A9 antigen, the developmental expression of this antigen in mouse embryos from 8 days post-coitum to 5 days post-partum was investigated by immunohistochemistry. At an early developmental stage, weak staining for R4-A9 antigen could be detected in the yolk sac. At later stages, strong staining of this antigen was detected predominantly in the embryonic liver, the main site of embryonic hematopoiesis. However, concomitant with the decreased staining in the liver, increased expression of this antigen was observed in bone marrow and spleen. Therefore, the changes in expression in those hematopoietic tissues suggest that its expression is coordinately regulated during the developmental stage of the sites of embryonic hematopoiesis. Compared with the distribution of R4-A9 antigen in adult tissues as previously reported, the expression of this antigen in fetal tissues was more widespread during the period of organogenesis, and was most abundant in other developing tissues, including the heart, skin, and lung. In contrast, fetal expression detected in hematopoietic and other developing tissues was lost after birth. These results taken together show a marked gradient of R4-A9 antigen expression, with the highest level at the peak of organ development, raising the possibility that this molecule may act as a growth/differentiation factor both in hematopoietic and other developing tissues in a fetus.

ADP-ribosyl Cyclase↗

Use of tissue-tinted porcelain to restore soft-tissue defects.

Anterior, partially edentulous residual ridges often have hard-tissue and soft-tissue defects that create esthetic and functional problems when conventional fixed prostheses are used to replace the missing teeth. However, tissue-tinted porcelain can be used in conjunction with fixed prostheses to solve many of these problems. Proper prosthesis design and shade matching are important considerations in the fabrication of fixed prostheses that incorporate tissue-tinted porcelain to restore hard-tissue and soft-tissue defects.

Cuspid↗

Methods for localization of hepatitis B surface antigen in liver tissue. An evaluation of different staining- and tissue preparation methods.

To investigate different staining techniques for demonstration of hepatitis B-surface antigen a series of 250 liver biopsies were stained with direct immunofluorescence (I.F.) on frozen tissue and indirect immunoperoxidase (I.P.), direct I.F., orcein and haema toxylin-eosin (H.E.) on paraffin embedded tissue. Examination of different fixatives and various fixation times of formalin fixed tissue on the demonstration of HBsAg was performed on liver tissue from one case with large amounts of HBsAg in the tissue. Among 70 HBsAg sero-positive cases only 27 were tissue positive. In 51 sero-positive AVH cases, 11 were positive with I.F., 3 with I.P., one with orcein and none with H.E. In the remaining 19 sero-positive cases, representing 9 cases with chronic hepatitis, 6 cases with cirrhosis, 3 cases with non-specific reactive changes and one case without pathological changes, 15 cases were positive with I.F. as well as with I.P., 9 with orcein and 5 with H.E. Membrane related staining reaction was best preserved when using Bouin's and Clarke's fixative. No difference was observed between different fixatives as regards intracytoplasmic staining reaction. Formalin fixation for more than 7 hours duration caused a decrease in the amount of demonstrable HBsAg, which only to a limited extent could be restored by pre-treatment with proteolytic enzyme.

Acute Disease↗

The determination of ofloxacin in human skin tissue by high-performance liquid chromatography and correlation between skin tissue concentration and serum level of ofloxacin.

A simple high-performance liquid chromatographic (HPLC) assay was developed for the measurement of ofloxacin in skin tissue, and the correlation between serum levels and skin tissue levels of ofloxacin was determined. The homogenized skin samples were directly introduced into an HPLC system after filtering through a Molcut II membrane filter to remove proteins. The filtrate was concentration on a pre-column using a phenyl-stationary phase and was then introduced to an analytical column using an ODS-stationary phase by column-switching techniques. Ofloxacin and lomefloxacin as an internal standard were detected by UV absorbance at 300 nm. Determination was possible for ofloxacin over the concentrated range 250-3000 ng (g skin tissue)-1; the limit of detection was 100 ng g-1. The absolute recovery of ofloxacin added to skin tissue homogenate was over 72% with a coefficient of variation of less than 4.1%. This method is applied to determination of skin tissue level of ofloxacin in patients after treatment with ofloxacin. The correlation between serum levels and skin tissue levels of ofloxacin was determined for 30 patients after oral administration of ofloxacin. Good correlation was obtained and the coefficient of correlation was 0.84.

Administration, Oral↗

Analysis of histone gene expression in adult tissues of the sea urchins Strongylocentrotus purpuratus and Lytechinus pictus: tissue-specific expression of sperm histone genes.

We analyzed the histone mRNA population found in several adult tissues of the sea urchin Strongylocentrotus purpuratus and in testis of Lytechinus pictus. Unique species of H1 and H2b mRNAs encoding the sperm-specific histone subtypes can be found exclusively in testis RNA. S. purpuratus contains two distinct testis-specific H1 transcripts, while L. pictus contains one such transcript. Each of these mRNAs is larger than either early or late embryonic H1 mRNAs. Other somatic adult tissues contain transcripts derived from members of the late embryonic H1 histone gene family. S. purpuratus contains one H2b transcript found exclusively in testis, while L. pictus contains two such H2b mRNAs. Similarly, in tissues other than testis, late H2b transcripts were found. While there is no sperm-specific H2a protein, a limited set of late histone H2a genes encoding primarily the H2a-beta subtype is expressed in testis. The majority of the H2a protein found in diploid adult tissues is also the H2a-beta subtype; however, the size of the H2a transcripts differs between testis and other tissues. We conclude that different members of the late H2a gene family are differentially expressed in embryos and adult tissues. We prepared and characterized cDNA clones encoding the sperm-specific H2b protein as well as the H2a-beta protein found in testis.

Amino Acid Sequence↗

Differential expression of CD34 in normal colorectal tissue, peritumoral inflammatory tissue, and tumour stroma.

AIMS: To investigate the role of CD34 positive stromal cells, namely dendritic interstitial cells, in the desmoplastic stroma formation of malignant epithelial neoplasms the distribution of CD34 positive stromal cells was examined in human colorectal adenocarcinomas, peritumoral inflammatory tissue, and normal tissue. METHODS: Forty one surgically resected human colorectal adenocarcinomas and their corresponding peritumoral inflammatory and normal tissues were examined. To distinguish CD34 positive stromal cells from vascular endothelial cells, immunostaining for both CD34 and CD31 was performed. The distribution of myofibroblasts was also analysed immunohistochemically, and double staining with CD34 and alpha smooth muscle actin (ASMA) was performed. RESULTS: Most of the stromal cells in the normal colorectal submucosa, muscularis propria, subserosa, and perirectal tissue were positive for CD34. In contrast, the peritumoral inflammatory tissue and the tumour stroma had no CD34 positive stromal cells. The distribution of myofibroblasts was almost the same as in the aforementioned series. No stromal cells double positive for CD34 and ASMA were detected in the peritumoral inflammatory tissues. CONCLUSIONS: Most stromal fibroblasts are CD34 positive stromal cells (dendritic interstitial cells). In colorectal adenocarcinomas, a lack of CD34 expression in stromal cells is associated with desmoplastic reaction.

Adenocarcinoma↗

Expression of the AQP-1 water channel in normal human tissues: a semiquantitative study using tissue microarray technology.

Aquaporin water channels are a family of membrane proteins that facilitate water movement across biological membranes. Aquaporin-1 (AQP-1) has been found to be important in osmotic water movement across cell membranes of epithelial and endothelial barriers. However, the distribution of AQP-1 in many normal human tissues is still unknown. The aim of this study was to use immunohistochemistry and semiquantitative histomorphometric analysis to determine the tissue distribution and relative expression of AQP-1 in normal human tissues using tissue microarray (TMA) technology. The normal human TMAs employed in this study included cardiovascular, respiratory, gastrointestinal, hepatic and pancreatobiliary, oral, salivary, nasal, mammary, fetal, endocrine, genital tract, central and peripheral nervous systems, urinary tract, skin, cartilage, and other soft connective tissues. Immunohistochemistry and semiquantitative histomorphometric analysis confirmed the presence of AQP-1 in endothelial barriers of almost all tissues and in many epithelial barriers. AQP-1 was highly expressed in the renal cortex, choroid plexus, and pancreatic ducts. AQP-1 expression levels were surprisingly high in the anus, gallbladder, and liver; moderate expression was also detected in the hippocampus and ependymal cells of the central nervous system. This is the first report of AQP-1 protein distribution in normal human TMAs. These findings confirm the presence of AQP-1 in human endothelia and selected water-transporting epithelia and several new locations, including mammary epithelium, articular chondrocytes, synoviocytes, and synovial microvessels where AQP-1 may be involved in milk production, chondrocyte volume regulation, synovial fluid secretion, and homeostasis, respectively.

Aquaporin 1↗

Expression profile of cancer-testis genes in 121 human colorectal cancer tissue and adjacent normal tissue.

PURPOSE: Among tumor antigens identified to date, cancer-testis (CT) antigens, which are coded by CT genes, are identified as a group of highly attractive targets for cancer vaccines. This study is the first to analyze the mRNA expression and possible correlation with pathologic characteristics of multiple CT genes in a large cohort of colorectal cancer (CRC) patients. EXPERIMENTAL DESIGN: The expression of 10 individual CT genes in 121 CRC and adjacent tissues were analyzed by RT-PCR method. The presence of autologous antibodies against NY-ESO-1 was examined in serum samples by ELISA. To confirm the protein expression, immunohistochemistry was done for detecting the NY-ESO-1 antigen in mRNA-positive CRC tissues. RESULTS: The CT genes were detected with various frequencies in CRC tissue, SCP-1, 1.7%; SSX-2, 2.5%; SSX-4, 2.5%; SSX-1, 5.0%; CT10, 6.6%; NY-ESO-1, 9.9%; MAGE-1, 11.6%; LAGE-1, 15.7%; MAGE-4, 22.3%; and MAGE-3, 27.3%. In 56.2% of tumor tissues examined in this study, at least one CT gene was detected. In contrast, no CT gene expression was found in cancer adjacent tissues. Among 10 CT genes investigated, NY-ESO-1 and LAGE-1 are of particular interest because their mRNA expression in CRC was rarely reported before. In our study, NY-ESO-1 mRNA was found to express in 9.9% of the samples, and also correlated significantly with stages (P = 0.041) and local lymph node metastasis (P = 0.002). In addition, we also identified one NY-ESO-1 antibody-positive serum sample. MAGE-4 mRNA was expressed at a high frequency in tumor tissues with vessel emboli samples (P = 0.025). CONCLUSIONS: These results suggested that CT genes, especially NY-ESO-1 and LAGE-1, do express in CRC. More than 50% of the CRC patients in this study express at least one CT gene, making them eligible for CT vaccination. NY-ESO-1 gene may serve as a marker for local metastasis and advanced disease. MAGE-4 gene is significantly associated with the vessel emboli.

Adult↗

Estrogen-receptor-negative breast cancer tissue is chemosensitive in vitro compared with estrogen-receptor-positive tissue.

The chemosensitivities of 18 estrogen-receptor-positive (ER+) tissues were compared with that of 38 estrogen-receptor-negative (ER-) tissues, using the in vitro succinate dehydrogenase inhibition test. These human breast tissue were exposed to six antitumor drugs: carboquone, adriamycin, mitomycin C, aclacinomycin A, cisplatin and 5-fluorouracil. Decrease in succinate dehydrogenase activity was noted in ER- compared to ER+ tissues, exposed to six antitumor drugs, in particular to adriamycin (p less than 0.001) and aclacinomycin A (p less than 0.05). The sensitive rates were higher in ER- than in ER+ tissues, against all six antitumor drugs. The resistance rates to all drugs tested were 25% in ER- and 45% in ER+ tissues. A higher chemosensitivity is associated with the absence of ER. It appeared that the ER status in case of breast cancer is an important predictor of the response to chemotherapy.

Aging↗

Antigen retrieval in formalin-fixed, paraffin-embedded tissues: an enhancement method for immunohistochemical staining based on microwave oven heating of tissue sections.

We describe a new approach for retrieval of antigens from formalin-fixed, paraffin-embedded tissues and their subsequent staining by immunohistochemical techniques. This method of antigen retrieval is based on microwave heating of tissue sections attached to microscope slides to temperatures up to 100 degrees C in the presence of metal solutions. Among 52 monoclonal and polyclonal antibodies tested by this method, 39 antibodies demonstrated a significant increase in immunostaining, nine antibodies showed no change, and four antibodies showed reduced immunostaining. In particular, excellent immunostaining results were obtained with a monoclonal antibody to vimentin as well as several different keratin antibodies on routine formalin-fixed tissue sections after pre-treatment of the slides with this method. These results showed that after antigen retrieval: (a) enzyme predigestion of tissues could be omitted; (b) incubation times of primary antibodies could be significantly reduced, or dilutions of primary antibodies could be increased; (c) adequate staining could be achieved in long-term formalin-fixed tissues that failed to stain by conventional methods; and (d) certain antibodies which were typically unreactive with formalin-fixed tissues gave excellent staining.

Antibodies, Monoclonal↗

Effects of N-acetylcysteine on tissue oxygenation in patients with multiple organ failure and evidence of tissue hypoxia.

Covert tissue hypoxia, particularly of the splanchnic region, appears important in the pathogenesis of multiple organ failure (MOF). This investigation evaluates the effects of N-acetylcysteine (NAC) upon several measures of tissue oxygenation in 10 patients with severe MOF and evidence of splanchnic hypoxia (as suggested by a pathologically low value (< 7.32) of the pH of the gastric mucosa (pHi)). Patients were studied following a prospective, randomized, placebo-controlled, cross-over design. Measurements included pulmonary and systemic haemodynamics, cardiac output by thermodilution, arterial and mixed venous blood gas values, blood lactate concentration, whole-body oxygen uptake by analysis of the expired gases, and pHi by tonometry. A complete set of measurements was obtained before and 45 min after the infusion of NAC (150 mg.kg-1 in 250 mL of saline) and, also, before and 45 min after the infusion of an equivalent volume of saline. NAC increased the cardiac index and vasodilated the systemic circulation (p < 0.01). However, O2 delivery to the tissues did not increase because the arterial oxygen content fell after NAC (p < 0.01). Mean O2 extraction or lactate concentration did not change after NAC, and pHi fell slightly (from 7.11 +/- 0.21 to 7.07 +/- 0.21; p < 0.05). The infusion of saline did not modify any variable significantly. The O2 extraction fraction increased exponentially in those patients with reduced O2 transport to the tissues. These results argue against a beneficial effect of N-acetylcysteine upon tissue oxygenation in patients with severe multiple organ failure and evidence of splanchnic hypoxia. Furthermore, they suggest that the mechanisms controlling the extraction of oxygen by the peripheral tissues in these patients were not impaired.

Acetylcysteine↗