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 163 records · Page 9Linked to original sources

Model of kinetic behavior of deoxyglucose in heterogeneous tissues in brain: a reinterpretation of the significance of parameters fitted to homogeneous tissue models.

Effects of tissue heterogeneity on regional CMRglc (rCMRglc) calculated by use of the deoxyglucose (DG) method at 45 min following the pulse of DG were evaluated in simulation studies. A theoretical model was developed to describe the kinetics of DG uptake and metabolism in heterogeneous brain tissues. Rate constants were fitted to simulation data for mixed tissue and rCMRglc computed on the basis of this tissue heterogeneity model. The results were compared with those obtained by use of the original model of the DG method for homogeneous tissue, both without (3K model) and with (4K model) a term to describe an apparent loss of deoxyglucose-6-phosphate (DG-6-P). As a direct consequence of tissue heterogeneity, the effective rate constant for phosphorylation of DG, k3*, declined with time. To compensate for the time-changing k3*, estimates of the dephosphorylation rate constant, k4*, were artifactually high when the 4K model was used, even though no dephosphorylation of DG-6-P actually occurred. The present study demonstrates that the finding of a significant k4*, at least within 45 min following a pulse of DG, may not represent dephosphorylation at all, but rather the consequence of measuring radioactivity in a heterogeneous tissue and applying a model designed for a homogeneous tissue. Furthermore, the high estimates of k4* resulted in significant overestimation of rCMRglc. When rCMRglc was computed with the conventional single-scan or autoradiographic method at 45 min after a pulse of DG, the 3K and tissue heterogeneity models yielded values that were within 5% of the true weighted average value for the heterogeneous tissue as a whole. We conclude that the effects of tissue heterogeneity alone can give the appearance of product loss, even when none occurs, and that the use of the 4K model with the assumption of product loss in the 45-min experimental period recommended for the DG method may lead to overestimation of the rates of glucose utilization.

Brain↗

Aryl hydrocarbon hydroxylase tissue-specific activities: evidence for baseline levels in mammalian tissues.

The tissue-specific activities (units per gram tissue) of arylhydrocarbon hydroxylase benzo[a]pyrene [AHH(BaP)] (EC 1.14.14.2) in human, mouse, rat, and hamster have been reviewed. Three categories of AHH activities are defined: baseline values from tissues that have been protected from adventitious exposures to AHH inducers; background levels from tissues where there have been no overt measures to protect against exposure; and induced levels resulting from overt exposure to chemical inducers. Evidence that the baseline category exists is derived from the observations that an upper limit of AHH tissue-specific activity of about 1.5 nmol/h . g tissue occurs in human placenta, human foreskin, lymphocyte, and epitheliod and fibroblastoid cell lines; mouse lung and liver; rat fetal liver, and noninducible rat cell lines from lung, liver, embryo kidney, and adrenals; and hamster kidney. The collected values for nonexposed tissues range from 0.02 nmol/h . g to values less than 1.5 nmol/h . g. The most consistent observation of this type was from human placental material from nonsmoking mothers. Animals raised under standard laboratory conditions without special dietary precautions show background AHH activities that range from 2 nmol/h . g to 200 nmol/h . g in portal of entry tissues such as liver, lung, and intestines. Almost all tissue samples showed induced AHH levels of up to 500 nmol/h . g when those tissues were overtly exposed to substances containing chemical inducers of AHH. Measurements of placental AHH from smoking mothers showed that more than 95% of those samples had AHH values exceeding 2.5 nmol/h . g. This natural bimodal distribution of AHH activities, across species and in different tissues, of baseline values of less than 1.5 nmol/h . g and background or induced AHH activities with values greater than 1.5 nmol/h . g, may provide a reference set of values for use in quantification of the role of AHH in the induction of disease.

Animals↗

Water transport in the midrib tissue of maize leaves : direct measurement of the propagation of changes in cell turgor across a plant tissue.

WATER MOVEMENT ACROSS PLANT TISSUES OCCURS ALONG TWO PATHS: from cell-to-cell and in the apoplasm. We examined the contribution of these two paths to the kinetics of water transport across the parenchymatous midrib tissue of the maize (Zea mays L.) leaf. Water relations parameters (hydraulic conductivity, Lp; cell elastic coefficient, epsilon; half-time of water exchange for individual cells, T((1/2))) of individual parenchyma cells determined with the pressure probe varied in different regions of the midrib. In the adaxial region, Lp = (0.3 +/- 0.3).10(-5) centimeters per second per bar, epsilon = 103 +/- 72 bar, and T((1/2)) = 7.9 +/- 4.8 seconds (n = seven cells); whereas, in the abaxial region, Lp = (2.5 +/- 0.9).10(-5) centimeters per second per bar, epsilon = 41 +/- 9 bar, and T((1/2)) = 1.3 +/- 0.5 seconds (n = 7). This zonal variation in Lp, epsilon, and T((1/2)) indicates that tissue inhomogeneities exist for these parameters and could have an effect on the kinetics of water transport across the tissue.The diffusivity of the tissue to water (D(t)) obtained from the sorption kinetics of rehydrating tissue was D(t) = (1.1 +/- 0.4).10(-6) square centimeters per second (n = 6). The diffusivity of the cell-to-cell path (D(c)) calculated from pressure probe data ranged from D(c) = 0.4.10(-6) square centimeters per second in the adaxial region to D(c) = 6.1.10(-6) square centimeters per second in the abaxial region of the tissue. D(t) approximately D(c) suggests substantial cell-to-cell transport of water occurred during rehydration. However, the tissue diffusivity calculated from the kinetics of pressure-propagation across the tissue (D(t)') was D(t)' = (33.1 +/- 8.0).10(-6) square centimeters per second (n = 8) and more than 1 order of magnitude larger than D(t). Also, the hydraulic conductance of the midrib tissue (Lp(m) per square centimeter of surface) estimated from pressure-induced flows across several parenchyma cell layers was Lp(m) = (8.9 +/- 5.6).10(-5) centimeters per second per bar (n = 5) and much larger than Lp.These results indicate that the preferential path for water transport across the midrib tissue depends on the nature of the driving forces present within the tissue. Under osmotic conditions, the cell-to-cell path dominates, whereas under hydrostatic conditions water moves primarily in the apoplasm.

Journal Article↗

The production of progesterone, androgens, and estrogens by granulosa cells, thecal tissue, and stromal tissue from human ovaries in vitro.

The concentrations of steroids in antral fluid, the number of granulosa cells, the status of the oocyte, and the diameter of each follicle were determined in human ovaries so that follicles at each stage of the menstrual cycle could be classified as large (greater than or equal to 8 mm diameter) or small (less than 8 mm diameter) and healthy or atretic. The granulosa cells and thecal-enriched tissue from each follicle and the stromal tissue from each ovary were cultured for 6 days in vitro. The amounts of progesterone (P), androstenedione (delta 4), testosterone, dihydrotestosterone, estrone, and estradiol (E2) generated by the different tissues were measured on days 0, 2, 4, and 6 of culture. It was found that granulosa cells, thecal tissue, and stromal tissue all have the biosynthetic capacity to produce P, delta 4, testosterone, dihydrotestosterone, estrone, and E2. No individual steroid-secreting compartment of the ovaries studied, whether part of the follicle or of the stroma, had the exclusive capability of producing any of the above-named steroids at any stage of the menstrual cycle or at any stage of antral follicle growth or atresia. Although the steroids produced by the human follicle appear not to be unique to any one cell type, the patterns of steroidogenesis by the granulosa and thecal compartments differ from one another and from the stroma throughout follicular maturation and atresia. During follicular development, granulosa cells produce large amounts of E2 and small amounts of delta 4. During the preovulatory phase, cells from large follicles (greater than or equal to 8 mm diameter) differentiate from an estrogen-secreting state into a P- and, to a lesser extent, an delta 4-secreting one. By contrast, during follicular atresia, granulosa cells continue to synthesize delta 4, but their capacity to synthesize estrogen is substantially reduced. Furthermore, granulosa cells from atretic follicles are incapable of transforming from an androgen-secreting state into a P-secreting one in tissue culture. During follicular growth, thecal tissue secretes about 2--3 times more delta 4 than E2. By contrast, during follicular atresia, thecal tissue retains its capacity to synthesize delta 4 but loses much of its capacity to synthesize E2. The in vitro capacity of thecal tissue to produce steroids exceeds that of the stroma (on a per weight basis) from 2- to 500-fold. Thecal tissue from healthy but not from atretic follicles is capable of differentiating from an androgen- and estrogen-secreting state to a predominantly P-secreting one in tissue culture. It is postulated that although steroid synthesis may not be rigidly compartmentalized during follicular development, appreciable amounts of the steroids secreted by the granulosa and theca may enter different compartments before leaving the ovary...

Adult↗

Automated assessment of the composition of breast tissue revealed on tissue-thickness-corrected mammography.

OBJECTIVE: Variations in the thickness of a compressed breast and the resulting variations in mammographic densities confound current automated procedures for estimating tissue composition of breasts from digitized mammograms. We sought to determine whether adjusting mammographic data for tissue thickness before estimating tissue composition could improve the accuracy of the tissue estimates. MATERIALS AND METHODS: We developed methods for locally estimating breast thickness from mammograms and then adjusting pixel values so that the values correlated with the tissue composition over the breast area. In our technique, the pixel values are corrected for the nonlinearity of the combined characteristic curve from the film and film digitizer; the approximate relative thickness as a function of distance from the skin line is measured; and the pixel values are adjusted to reflect their distance from the skin line. To estimate tissue composition, we created a backpropagation neural network classifier from features extracted from the histogram of pixel values, after the data had been adjusted for characteristic curve and tissue thickness. We used a 10-fold cross-validation method to evaluate the neural network. The averaged scores of three radiologists were our gold standard. RESULTS: The performance of the neural network was calculated as the percentage of correct classifications of images that were or were not corrected to reflect tissue thickness. With its parameters derived from the pixel-value histogram, the neural network based on corrected images performed better (71% accuracy) than that based on uncorrected images (67% accuracy) (p < 0.05). CONCLUSION: Our results show that adjusting tissue thickness before estimating tissue composition improved the performance of our estimation procedure in reproducing the tissue composition values determined by radiologists.

Aged↗

[Optical properties of human normal small intestine tissue with theoretical model of optics about biological tissues at Ar+ laser and 532 nm laser and their linearly polarized laser irradiation in vitro].

A double-integrating-spheres system, basic principle of measuring technology of ray radiation, and optical model of biological tissues were used for the study. Optical properties of human normal small intestine tissue at 476.5, 488, 496.5, 514.5 and 532 nm laser and their linearly polarized laser irradiation were studied. The results of measurement showed that the total attenuation coefficient and scattering coefficient of the tissue at these wavelengths of laser and their linearly polarized laser irradiation increased with decreasing wavelengths. And obviously there was a distinction at 514.5 to 532 nm wavelength between lasers and their linearly polarized laser irradiation. Absorption coefficient of tissue at these wavelengths of laser and their linearly polarized laser irradiation increased with decreasing wavelengths. Absorption coefficient of tissue at 514.5 to 532 nm wavelength of laser was obviously decreasing, which was independent of these wavelengths of laser or their linearly polarized laser irradiation. Mean cosine of scattering of tissue at these wavelengths of laser and their linearly polarized laser irradiation also increased with decreasing wavelengths. But penetration depth of tissue at these wavelengths of laser and their linearly polarized laser irradiation also increased with increasing of wavelengths. Refractive index of tissue between these wavelengths of laser was within 1.38 to 1.48. Absorption coefficient, scattering coefficient, total attenuation coefficient, effective attenuation coefficients of tissue in Kubelka-Munk two-flux model at the same wavelength of laser and their linearly polarized laser irradiation showed no prominent distinction (P>0.01). Absorption coefficient, scattering coefficient, total attenuation coefficient, effective attenuation coefficients of tissue in Kubelka-Munk two-flux model at different wavelength of laser and their linearly polarized laser irradiation showed obvious distinction. Optical properties of tissue at 514.5 to 532 nm wavelength of laser exhibited obvious distinction.

Absorption↗

[Transference of antibiotics into prostatic tissues: sampling method by transurethral resection for the measurement of the concentration of antibiotics in prostatic tissue].

The transeference of two antibiotics, i.e. cefmetazole (CMZ) and fosfomycin (FOM), into prostatic tissues was examined. Prostatic tissue samples were obtained from patients with benign prostatic hyperplasia while undergoing open prostatectomy or transurethral resection of the prostate (TUR-P). 2 g of CMZ or 4 g of FOM was intravenously administered within about 10 minutes starting 1 hour before the removal or resection of the prostate, and blood samples were collected at the end of the administration and during surgery. In TUR-P, resected prostatic tissues were washed with the TUR perfusate and the antibiotic in the tissue was presumed to be released into the perfusate. The following preliminary experiments were, therefore, carried out. The removed prostate was divided into three segments, i.e. urethral region, central region and capsular region, and the CMZ or FOM level in each tissue was measured. The remaining tissues were cut into small pieces for immersion in the TUR perfusate for 10-90 minutes. The tissue fragments were removed every 10 minutes to measure the tissue concentration of CMZ or FOM. The concentration of CMZ or FOM in the prostatic tissues did not vary among the three regions, however it markedly decreased with increase in the period of immersion. This suggested that the concentration of these agents into the prostatic tissues was represented by the concentration in the tissues near the urethra obtained immediately after the start of TUR-P.(ABSTRACT TRUNCATED AT 250 WORDS)

Anti-Bacterial Agents↗

Transplantation of parathyroid tissue in experimental hypoparathyroidism: in vitro and in vivo function of parathyroid tissue microencapsulated with a novel amitogenic alginate.

Microencapsulation of tissues is an alternative to postoperative immunosuppression in transplantation. In 1994 iso-, allo- and xenotransplantation of microencapsulated parathyroid tissue was achieved in vivo. However, continued analysis of the coating substance (an alginate) determined mitogenic properties. Here, we report on the in vitro and in vivo function of parathyroid tissue microencapsulated with a novel amitogenic alginate suitable for use in humans. To assess in vitro function, parathyroid tissue encapsulated with mitogenic and amitogenic alginate was exposed to rising concentrations of calcium. For in vivo experiments, it was isotransplanted into parathyroidectomized rats. PTH release into medium and PTH serum levels as well as calcium levels of recipient rats were analyzed and compared to native (non-microencapsulated) tissue and empty capsules, respectively. In vivo, transplants were excised and subjected to histologic examination six months after trans-plantation. In vitro, parathyroid tissue encapsulated with amitogenic alginate releases approximately half of the PTH of the native tissue, not different from tissue encapsulated with the mitogenic alginate. In vivo, the novel alginate preserved parathyroid function similar to that of native tissue over the six month period resulting in complete reversal of hypoparathyroidism. Correspondingly, histologic examination revealed vital parathyroid tissue in intact microcapsules. By establishing in vitro function and successful long-term transplantation, we have documented the principle of microencapsulation of parathyroid tissue to be effective also with the novel amitogenic alginate, which is suitable for clinical use.

Alginates↗

Adipose tissue engineering: the future of breast and soft tissue reconstruction following tumor resection.

Reconstructive surgeons have always been at the forefront of medical technology. The history of reconstructive surgery began with ablative surgery, which was followed by tissue and organ transplantation, leading to contemporary tissue reconstruction. The field of reconstructive surgery is poised at the next stage of its evolution, namely tissue regeneration. The field of tissue engineering has largely defined this evolutionary leap. One active area of investigation is the development of tissue engineering strategies for adipose tissue. Bioengineers, life scientists, and reconstructive surgeons are synergistically coupling expertise in areas such as cell culture technology, tissue transfer, cell differentiation, angiogenesis, computer modeling, and polymer chemistry to regenerate adipose tissue de novo for breast replacement and soft-tissue augmentation following tumor resection. This work presents the current state of the art in adipose tissue engineering, as well the clinically translatable strategies currently under development. Semin. Surg. Oncol. 19:302-311, 2000.

Adipose Tissue↗

Monkey leptin receptor mRNA: sequence, tissue distribution, and mRNA expression in the adipose tissue of normal, hyperinsulinemic, and type 2 diabetic rhesus monkeys.

OBJECTIVE: We have cloned the rhesus monkey leptin receptor and examined its mRNA expression levels in the adipose tissue of monkeys to investigate the regulation of gene expression of the leptin receptor. RESEARCH METHODS AND PROCEDURES: Monkey leptin receptor cDNA was cloned by reverse transcriptase-polymerase chain reaction (RT-PCR). Tissue distribution of monkey leptin receptor was examined by Northern blot analysis and RT-PCR. The mRNA levels of monkey leptin receptor in adipose tissue of normal (n=10), hyperinsulinemic obese (n=8), and type 2 diabetic monkeys (n=8) were measured by quantitative RT-PCR. RESULTS: Monkey leptin receptor cDNA had at least two alternatively spliced isoforms (long and short forms). The long form of the leptin receptor mRNA was expressed relatively highly in liver, adipose tissue, hypothalamus, and choroid plexus, whereas the total leptin receptors were expressed in every tissue examined. The mRNA levels of the long form of the leptin receptor in adipose tissue were not correlated to body weight, fasting plasma insulin, plasma glucose, or plasma leptin levels. The mRNA levels of the long form of the leptin receptor were highly correlated to that of the total leptin receptor (long and short form). DISCUSSION: The long form of leptin receptor mRNA existed in adipose tissue as well as in liver and hypothalamus, suggesting that the leptin receptor in adipose tissue may be functional in adipose tissue. The expression of the leptin receptor mRNA in adipose tissue is not affected by obesity, hyperinsulinemia, or diabetes.

Adipose Tissue↗

Mesenteric adipose tissue-derived monocyte chemoattractant protein-1 plays a crucial role in adipose tissue macrophage migration and activation in obese mice.

OBJECTIVE: To determine whether chemokines, which play a pivotal role in monocyte/macrophage trafficking, modulate macrophage infiltration into and activation in the adipose tissues. RESEARCH METHODS AND PROCEDURES: Various types of adipose tissue were isolated from different fat depots (e.g., mesenteric, epididymal, renal, and subcutaneous adipose tissues) from obese mice fed a high-fat diet and from non-obese controls fed a standard diet. The isolated tissues were cultured for 24, 48, and 72 hours. The level of monocyte chemoattractant protein-1 (MCP-1) expression and the amount of protein released were measured by reverse transcriptase-polymerase chain reaction or enzyme-linked immunosorbent assay, respectively. Chemotaxis assay was performed to measure the degree of macrophage migration. Macrophage activation was estimated by measuring the concentrations of nitric oxide and tumor necrosis factor alpha. RESULTS: The level of MCP-1 mRNA expression, protein content, and the amount of protein released significantly increased in the adipose tissues from the obese mice compared with those from the non-obese mice. The mesenteric adipose tissue produced the highest levels of MCP-1 protein among the four different fat depots. Mesenteric adipose tissue-conditioned medium induced the highest degree of macrophage migration and strongly induced macrophages to produce proinflammatory mediators such as nitric oxide and tumor necrosis factor alpha. The neutralization of MCP-1 in the adipose tissue-conditioned medium significantly inhibited the migration and activation of macrophages. DISCUSSION: Our findings suggest that MCP-1 plays a crucial role in adipose tissue inflammatory response by activating and inducing the infiltration of macrophages into adipose tissues. MCP-1 may be closely associated with visceral obesity-related complications and, thus, may be a useful therapeutic target for modulating visceral obesity-related diseases.

Adipose Tissue↗

Tissue-specific expression of the human aromatase cytochrome P-450 gene by alternative use of multiple exons 1 and promoters, and switching of tissue-specific exons 1 in carcinogenesis.

Extensive screening of aromatase cDNA was carried out in cDNA libraries from various human tissues. The DNA sequences of all the isolated cDNA clones were identical in the region encoded by exons 2-10 of the aromatase gene. However, tissue-specific sequences, which were classified into four groups, were observed in the 5' portions of the clones corresponding to the region encoded by exon 1. All of them were also found in clones isolated from a human genomic library and mapped between exons 1 and 2 of the human aromatase gene reported previously, suggesting the presence of multiple exons 1 and promoters in the gene. Reverse transcription-PCR analyses of aromatase mRNAs in various tissues revealed that aromatase transcripts are tissue-specifically spliced by alternative use of multiple exons 1, although minor forms of the transcripts were also present in each tissue. Aromatase mRNA is spliced from 10 exons in most tissues, but from 9 exons in the prostate and from 10 or 11 exons in the placenta. This suggests that tissue-specific regulation of the aromatase gene in various tissues may be explained by alternative use of multiple exons 1 flanked with tissue-specific promoters. The alternative use of multiple exons 1 for liver transcripts was found to change developmentally. Furthermore, switch from an adipose-specific exon 1 to another type of exon 1 was observed in aromatase transcripts of adipose tissues of three of five breast cancer patients.

Adipose Tissue↗

Rat mitochondrial glycerol-3-phosphate dehydrogenase gene: multiple promoters, high levels in brown adipose tissue, and tissue-specific regulation by thyroid hormone.

Mitochondrial FAD-linked glycerol-3-phosphate dehydrogenase (mtGPDH) is one of the two enzymes of the glycerol phosphate shuttle. This shuttle transfers reducing equivalents from the cytoplasm to the mitochondria in a unidirectional, exothermic manner. Here, the isolation and characterization of the rat nuclear gene (Gpd2) encoding mtGPDH is reported. The mtGPDH gene spans 100 kb and consists of 17 exons. The use of alternate promoters was suggested by the presence of three different first exons and confirmed by transient expression for two of them. The first exons are expressed in a tissue-restricted manner. Exon 1a was found primarily in brain, exon 1b was used in all tissues examined, and exon 1c was detected predominantly in testis. Depending on the tissue, different transcript lengths were also observed: 5.9 kb (all tissues), 3.6 kb (skeletal muscle), and 2.5 kb (testis). The length isoforms are attributable to alternate splicing and polyadenylation site use. Very high mtGPDH mRNA levels were found in brown adipose tissue, 75 fold greater than in white adipose tissue. Thyroid hormone increased mtGPDH mRNA levels in liver and heart but not in brown adipose tissue, brain, or testis. This pattern corresponds to that of thyroid hormone-induced oxygen consumption and is consistent with a role for mtGPDH in thyroid hormone-induced thermogenesis. Both thyroid-responsive and nonresponsive tissues used promoter 1b, suggesting that tissue-specific factor(s) contribute to the tissue-restricted responsiveness to thyroid hormone.

Adipose Tissue, Brown↗

Soft tissue for allograft reconstruction of the human knee: a survey of the American Association of Tissue Banks.

With increasing use and availability of musculoskeletal soft tissue allografts, orthopaedic surgeons need current knowledge about allograft processing, costs, and availability. In conjunction with the American Association of Tissue Banks, a comprehensive survey consisting of specific questions on several topics in tissue banking was sent to 42 member banks or banks undergoing accreditation review that distribute musculoskeletal tissues. Donors came from organ procurement organizations, coroners' offices, hospital morgues, and donations; the average age of the donors was 35. Most of the 36 tissue banks responding to the questionnaire harvest patellar and Achilles tendons. Patellar tendon demand exceeded supply. Tissue processing was done by outside organizations approximately 50% of the time. Of the four types of tissue sterilization processes performed, gamma irradiation was the most common. Doses of sterilizing gamma irradiation varied from 1 to 3.5 mrad. The average approximate costs of fresh-frozen tissue were $800 for patellar tendon allograft, $615 for Achilles tendon, and $640 for menisci. There was no consensus of opinion of how to size or sterilize meniscal allografts. As demand increases for soft tissue allografts, it is essential that the orthopaedic surgeon is knowledgeable about the clinical impact of tissue banking.

Adolescent↗

An informatics model for tissue banks--lessons learned from the Cooperative Prostate Cancer Tissue Resource.

BACKGROUND: Advances in molecular biology and growing requirements from biomarker validation studies have generated a need for tissue banks to provide quality-controlled tissue samples with standardized clinical annotation. The NCI Cooperative Prostate Cancer Tissue Resource (CPCTR) is a distributed tissue bank that comprises four academic centers and provides thousands of clinically annotated prostate cancer specimens to researchers. Here we describe the CPCTR information management system architecture, common data element (CDE) development, query interfaces, data curation, and quality control. METHODS: Data managers review the medical records to collect and continuously update information for the 145 clinical, pathological and inventorial CDEs that the Resource maintains for each case. An Access-based data entry tool provides de-identification and a standard communication mechanism between each group and a central CPCTR database. Standardized automated quality control audits have been implemented. Centrally, an Oracle database has web interfaces allowing multiple user-types, including the general public, to mine de-identified information from all of the sites with three levels of specificity and granularity as well as to request tissues through a formal letter of intent. RESULTS: Since July 2003, CPCTR has offered over 6,000 cases (38,000 blocks) of highly characterized prostate cancer biospecimens, including several tissue microarrays (TMA). The Resource developed a website with interfaces for the general public as well as researchers and internal members. These user groups have utilized the web-tools for public query of summary data on the cases that were available, to prepare requests, and to receive tissues. As of December 2005, the Resource received over 130 tissue requests, of which 45 have been reviewed, approved and filled. Additionally, the Resource implemented the TMA Data Exchange Specification in its TMA program and created a computer program for calculating PSA recurrence. CONCLUSION: Building a biorepository infrastructure that meets today's research needs involves time and input of many individuals from diverse disciplines. The CPCTR can provide large volumes of carefully annotated prostate tissue for research initiatives such as Specialized Programs of Research Excellence (SPOREs) and for biomarker validation studies and its experience can help development of collaborative, large scale, virtual tissue banks in other organ systems.

Databases as Topic↗

Perinodal adipose tissue and fatty acid composition of lymphoid tissues in patients with and without Crohn's disease and their implications for the etiology and treatment of CD.

The physiological bases for roles of adipose tissue and fatty acids in the symptoms and dietary treatments of Crohn's disease are poorly understood. The hypothesis developed from experiments on rodents that perinodal adipocytes are specialized to provision adjacent lymphoid tissues was tested by comparing the composition of triacylglycerol fatty acids in homologous samples of mesenteric adipose tissue and lymph nodes from patients with or without Crohn's disease. Mesenteric perinodal and other adipose tissue, and lymph nodes, were collected during elective surgery for Crohn's disease and other conditions. Fatty acids were extracted, identified, and quantified by thin-layer and gas-liquid chromatography. Perinodal adipose tissue contained more unsaturated fatty acids than other adipose tissue in controls, as reported for other mammals, but site-specific differences were absent in Crohn's disease. Lipids from adipose and lymphoid tissues had more saturated fatty acids, but fewer polyunsaturates in Crohn's disease patients than controls. In adipose tissue samples, depletion of n-3 polyunsaturates was greatest, but n-6 polyunsaturates, particularly arachidonic acid, were preferentially reduced in lymphoid cells. Ratios of n-6/n-3 polyunsaturates were higher in adipose tissue but lower in lymphoid cells in Crohn's disease patients than in controls. Site-specific differences in fatty acid composition in normal human mesentery are consistent with local interactions between lymph node lymphoid cells and adjacent adipose tissue. But these site-specific properties are absent in Crohn's disease, causing anomalies in composition of lymphoid cell fatty acids, which may explain the efficacy of elemental diets containing oils rich in n-6 polyunsaturates.

Adipose Tissue↗

[A study on guided tissue regeneration and tissue engineering-transplantation of collagen membrane seeded with cultured hyaline chondrocytes].

OBJECTIVE: Lack of transplant material is a main problem in the repair and reconstruction of tissue or organ defects. To seek the succedaneum of transplants, we studied and used tissue-engineered growth hyaline cartilage. METHODS: The articular hyaline cartilage obtained from newborn calf within 6 hours of sacrifice was enzymatically dissolved. The chondrocytes were then seeded onto the medical collagen membrane of guided tissue regeneration in a 24 well plate in RPMI1640 medium. One week later, the chondrocyte medical collagen membrane of guided tissue regeneration complex was implanted subcutaneously into the back of nude mice. Eight weeks after implantation, the animals were sacrificed. RESULTS: The present study seems to demonstrate that the cartilage-like tissue was strong enough to be transferred after being implanted for 8 weeks. The cartilage-like tissue was proved to be tissue-engineered hyaline cartilage by HE stain. The chondrocytes could secrete chondroitin sulfate as proved by Lev-Spicer stain. CONCLUSION: Tissue engineering technique was used to make tissue-engineered cartilage in vitro. It will provide a new transplant material for the repair of tissue or organ defects.

Animals↗

[Different types of tissue transplantation in repairing tissue defects and function reconstruction].

OBJECTIVE: To explore the clinical effect of different types of free tissue transplantation on repairing tissue defects and reconstructing functions. METHODS: From November 2001 to September 2004, 14 types of free tissue transplantation and 78 free tissue flaps were applied to repairing tissue defects and reconstructing functions in extremities and maxillofacial region in 69 cases. Of the 69 cases, there were 53 males and 16 females (their ages ranged from 18 to 56, 31 on average). Five cases were repaired because of skin defects in foot, 22 cases were repaired because of skin defects in leg, 36 cases were repaired as the result of skin defects in hand or forearm and finger reconstruction, 3 cases were restored by virtue of ulna or radius defects, and 3 cases were repaired in maxillofacial region. There were 55 cases of open wound, in which 16 cases were infectious wound, 6 cases were osteomyelitis or pyogenic arthritis. There were 14 cases of non-infectious wound. The area of these tissue flaps ranged from 2.0 cm x 1.5 cm to 43.0 cm x 12.0 cm. The length of bone transplantation ranged from 10 cm to 15 cm. RESULTS: Arterial crisis occurred in 2 cases, venous crisis occurred in 2 cases. Seventy-six flaps survived completely and 2 flaps survived partially which were later healed. Fifty-two cases were healed at stage I, 13 cases were healed at stage I (healing time ranged from 20 to 30 days), purulent infection occurred to 4 cases(healing time ranged from 3 to 11 months). Bone healing time ranged from 6 to 8 weeks in finger reconstruction. Bone healing time ranged from 4 to 6 months in fibula transplantation. The function reconstruction and appearance were satisfying. The functions of all regions, where free tissues were supplied, were not disturbed. CONCLUSION: Tissue transplantation and composite tissue transplantation are effective in repairing tissue defects and reconstructing functions.

Adolescent↗