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Spasm following coronary artery bypass graft surgery has been well established in arterial grafts, especially in grafts utilizing the internal mammary. Venous graft spasms are uncommon and are only observed in vein grafts during or soon after the coronary artery bypass surgery. It is exceedingly rare to see spasm of venous graft beyond one year of surgery. We report a 72-year-old female who had coronary artery bypass graft three years ago and presented with new onset chest pain for one month. The coronary angiogram revealed severe spasm of the proximal aspect of a patent saphenous venous graft which was relieved by intracoronary nitroglycerine. Patient was successfully managed using combination of antispasmodic medications (nitrates and calcium channel blockers) leading to long-term resolution of her anginal symptoms. [ABSTRACT FROM AUTHOR]

Background Autologous venous grafts generally give best results for arterial bypass grafting in cases of arterial stenosis. When no suitable venous graft can be found, synthetic prosthetic graft may be an alternative. Prostheses are easily accessible but susceptible to infection. In these cases, the replacement of infected prosthesis by the human arterial allograft is the best treatment option. The question arises whether we could prepare a graft meeting mechanical conditions of an artery immunologically inert and resistant to bacterial infection. Materials and methods LEW and BN rat aortic segments were placed in dehydrated sodium chloride and stored for 1 to 12 mo. Then, they were transplanted orthotopically as aortic grafts for 3 to 15 mo in syngenic and allogenic combination. No immunosuppression was used. Patency, pulsation, and frequency of development of aneurysms were studied. The tensile strength and maximum intraluminal pressures were measured. Morphology of grafts was evaluated on histology and electron microscopy. The endothelial and infiltrating cells were identified. Results Transplanted allogeneic aortic grafts preserved in anhydrous sodium chloride up to 12 mo remained patent for 15 mo. Hypertrophy of intima with endothelial cells lining the inner surface and single muscle cells between elastic fibers were seen. Normal structure of collagen and elastic fibers was maintained. Only minor-host mononuclear infiltrates were seen around the preserved allografts. Conclusions Rat aortas preserved in anhydrous sodium chloride retain patency and function even 15 mo after transplantation. Such grafts retain their wall structure and evoke only minor recipient reaction. Our results confirm that anhydrous sodium chloride may be used for arterial grafts preservation. Low immunogenicity is additional advantage. [ABSTRACT FROM AUTHOR]

BACKGROUND: Reoperations for bypass surgery increase the need for new grafts. We investigated early changes in both the normal human saphenous vein and in ectatic varicose veins externally supported by PTFE (polytetrafluoroethylene) graft and exposed to arterial pressure in an IN VITRO non-pulsatile flow model. MATERIAL AND METHODS: A total of 24 saphenous vein pieces (11 of them normal, the other 13 with varicosities) with a length of 6 centimeters were divided into equal parts; half of these parts were wrapped in PTFE grafts. All vein parts were placed in a perfusion circuit. Tissue biopsies were obtained from the vein segments. Light and electron microscopy examinations were performed, and endothelial continuity, elastic laminate continuity, medial connective tissue uniformity, medial smooth muscle uniformity, and adventitial connective tissue uniformity parameters were identified. RESULTS: All parameters in the PTFE protected vein groups were better. The fewest morphological changes among all four groups were detected in the vein walls from normal veins with PTFE protection. There was no significant difference in endothelial continuity and adventitial connective tissue uniformity between the normal vein group and the varicose vein group with PTFE protection. CONCLUSIONS: It is suggested that supporting vein grafts externally with PTFE sufficiently protects the vein walls against damage from exposure to arterial pressure. If varicose veins are used as arterial grafts, supporting them with PTFE may be useful because of the good protection of endothelial and medial connective tissues, resulting in similar parameters to those of normal vein walls. [ABSTRACT FROM AUTHOR]

Background: Cold storage of arteries for reconstructive and bypass surgery may result in injury of endothelial cells which may promote low perfusion and graft vasculopathy. Methods: A recently developed N-acetyl histidine-buffered, potassium-chloride enriched, and amino acid-fortified vascular storage solution augmented with iron chelators deferoxamine (100 μmol/L) and LK 614 (20 μmol/L) was studied in the rat superior mesenteric artery and aorta with respect to: (1) potassium-induced vessel tone, (2) endothelium-dependent and -independent relaxation, and (3) endothelial nitric oxide synthase (eNOS) protein expression over 4-days cold storage (4°C).This solution was compared with traditional storage solutions, histidine-tryptophan-ketoglutarate (HTK) and physiological saline solution (PSS). Results: Vessels stored for 4 days in the new solution were significantly better protected than those stored in traditional HTK or PSS. The protective effects comprised: (1) vessel tone development after stimulation with potassium-chloride solution, (2) endothelium-dependent and -independent vessel relaxation, and (3) eNOS expression. With iron chelators (deferoxamine 100 μM, LK 614 20 μM) present in the storage solution, endothelium-dependent relaxations (eNOS-dependent and KCa-channel-dependent) were fully maintained after 96 hours of cold storage. Endothelial cell structure was significantly better maintained after 96 hours in the new solution than in HTK or PSS solutions. Already, 2 hours of cold storage in HTK resulted in a significant loss of structurally intact endothelium. The structural changes correlated significantly with the diminished vessel relaxation capacity. Furthermore, tissue reductive capacity was only preserved after 96 hours storage if the new solution was used. Conclusion: The new storage solution is superior to traditional HTK and PSS cold storage with respect to: (1) preservation of vessel structure and function; (2) the presence of iron chelators significantly improved protection of endothelial function; and (3) the new solution permits cold vessel storage for a minimum of 4 days with full maintenance of endothelial function and its coupling to smooth muscle. [Copyright &y& Elsevier]

Abstract: N-nitrosodiethylamine (NDEA) is one of the important carcinogenic nitrosamines frequently present in human environment and food chain that poses a significant human health hazard. This study was planned to investigate the protective role of dietary fibre on NDEA-induced toxicity in hypercholesterolemic rats. Oral administration of NDEA at a dose of 100mg/kg diet to experimental rats under hypercholesterolemic conditions evoked severe biochemical and pathological changes. Supplementation of chickpea (Cicer arietinum L.) seed coat fibre in the diet along with NDEA reduced its biochemical and pathological effects. There was a reduction in the hepatotoxic effects of NDEA as evidenced by decreased hepatic degeneration and improved liver weight index. Administration of NDEA resulted in a significant increase in the osmotic fragility of erythrocytes. The antioxidant activity of experimental animals decreased in the NDEA-fed group, which was evident by increased in vitro lipid peroxidation (LPO) of erythrocytes. However, chickpea seed coat fibre considerably reduced the peroxidative damage done by NDEA. Administration of NDEA also resulted in a significant increase in LPO in all the tissues to a varying degree, although the effect on antioxidant potential was variable in different tissues. However, chickpea seed coat fibre reduced the effect of NDEA on LPO and antioxidant potential of various tissues, providing reasonable protection against NDEA-induced oxidative stress and hence its toxicity. Histopathological analysis of different tissues (heart, liver and lungs) showed decrease in the severity of pathological changes among the experimental animals when they were given NDEA along with chickpea seed coat fibre in the diet as compared with giving NDEA alone. Our study therefore, emphasizes the importance of including dietary fibre in the diet, in combating the ill-effects of nitrosamines such as NDEA, particularly on the antioxidant status of the body. [Copyright &y& Elsevier]

Abstract: The present study was designed to understand the effects of sublethal dosages of dichlorvos (DIC) and methyl parathion (MP) on acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) in various tissues of rats exposed to 5 and 10ppm of DIC and MP in drinking water ad libitum for 28days continuously. According to the results, AChE activity was significantly decreased in all the tissues of rats treated with both dosages of DIC and MP except for in the lungs treated with both dosages of DIC. With regard to the BChE, MP caused a significant decrease in the liver, heart and lungs with 5ppm dosage whereas it did not change the BChE activity in the other tissues with two dosages. Also, DIC caused a significant decrease in BChE activity in the heart tissue treated with both dosages and in the brain of rats treated with 5ppm. The observations presented led us to conclude that the administrations of MP and DIC at sublethal concentrations inhibited AChE and BChE activities in the rats. These results suggest that inhibition of AChE may be a better biomarker for the assessment of neurotoxic effects in the living. [Copyright &y& Elsevier]

Tomographic biomedical images are commonly affected by an imaging artefact known as the partial volume (PV) effect. The PV effect produces voxels composed of a mixture of tissues in anatomical magnetic resonance imaging (MRI) data resulting in a continuity of these tissue classes. Anatomical MRI data typically consist of a number of contiguous regions of tissues or even contiguous regions of PV voxels. Furthermore discontinuities exist between the boundaries of these contiguous image regions. The work presented here probabilistically models the PV effect using spatial regularization in the form of continuous Markov random fields (MRFs) to classify anatomical MRI brain data, simulated and real. A unique approach is used to adaptively control the amount of spatial regularization imposed by the MRF. Spatially derived image gradient magnitude is used to identify the discontinuities between image regions of contiguous tissue voxels and PV voxels, imposing variable amounts of regularization determined by simulation. Markov chain Monte Carlo (MCMC) is used to simulate the posterior distribution of the probabilistic image model. Promising quantitative results are presented for PV classification of simulated and real MRI data of the human brain. [ABSTRACT FROM AUTHOR]

Abstract: Iron overload may enhance oxidative damage. Growth hormone (GH) and insulin-like growth factor-I (IGF-I) are involved in oxidative processes, lipid peroxidation (LPO) included. The aim of the study was to evaluate the in vivo effects of GH, IGF-I and/or iron on LPO in rat tissues. Male Wistar rats were administered iron (Fe2+; 3mg/100g b.w., i.p., on the 8th day) and/or GH (0.2IU/100g b.w.), and/or IGF-I (2μg/100g b.w.) once daily for 8 days. LPO products (malondialdehyde+4-hydroxyalkenals) were measured in rat brain, lung, small intestine, liver, kidney, testis, spleen and serum. Iron injection increased LPO only in the small intestine and that effect was completely prevented by either GH or IGF-I. In the brain, GH decreased, whereas IGF-I increased, the basal LPO. GH and IGF-I possess some ability to prevent iron-induced oxidative damage in iron sensitive tissues, but contribute to oxidative imbalance in other tissues. [Copyright &y& Elsevier]

Abstract: Culture of the pleasure oyster Crassostrea corteziensis is emerging as an alternative to the Pacific oyster (Crassostrea gigas) for oyster producers, who face severe mortalities since 1997 in Northwest México. For determining the health status of this species, we conducted a histopathological analysis of cultured populations from two estuaries in the Pacific coast of México. Macroscopical analysis revealed animals with transparent and retracted mantle. Histopathological analysis of these specimens showed tissue alterations and parasitic forms consistent with Perkinsus sp. infection. Stages of the parasite identified included tomont and trophozoites with an eccentric vacuole characteristic of Perkinsus spp. Pieces of tissues of infected oysters were incubated in Fluid Thioglycollate Medium (FTM) resulting in blue–black hypnospores after incubation. The identity of the parasite was confirmed by species specific PCR-based assay in DNA samples from oysters, tissue fractions from FTM cultures, and deparaffined samples with Perkinsus-like parasite detected by histology. Sequencing of positive amplified fragments (307bp) showed a sequence similar to Perkinsus marinus strain TXsc NTS ribosomal RNA gene (100% coverage and 98% identity, GenBank Accession No. AF497479.1) and to P. marinus, Genomic DNA, (100% coverage and 97% identity, GenBank Accession No. S78416.1). The prevalence of P. marinus varied from 1 to 5% in Boca del Camichín and from 1 to 6% in Pozo Chino. In general, the intensity of infection was moderate. The infection was observed in oysters from 31 to 110mm of shell length. This is the first record of P. marinus in oysters from the North America Pacific coast and the first record in C. corteziensis. The origin of this parasite in the area is unknown, but it may be associated to introductions of Crassostrea virginica from the East coast of United States of America or Gulf of México. [Copyright &y& Elsevier]

Abstract: In this paper, a fully variational constitutive model of soft biological tissues is formulated in the finite strain regime. The model includes Ogden-type hyperelasticity, finite viscosity, deviatoric and volumetric plasticity, rate and microinertia effects. Variational updates are obtained via time discretization and pre-minimization of a suitable objective function with respect to internal variables. Genetic algorithms are used for model parameter identification due to their suitability for non-convex, high dimensional optimization problems. The material behavior predicted by the model is compared to available tests on swine and human brain tissue. The ability of the model to predict a wide range of experimentally observed behavior, including hysteresis, cyclic softening, rate effects, and plastic deformation is demonstrated. [Copyright &y& Elsevier]

Abstract: A validation of fluorescence in situ hybridization (FISH) assays for paraffin-embedded tissues (PET) is required before clinical use. Although the FISH probe validation process for hematologic disorders has been described during recent years, none of these descriptions, to our knowledge, address the validation process for paraffin-embedded tissues in detail. We describe an applicable preclinical validation process. The following five-step validation is outlined: (1) pathologist''s review of slide; (2) probe validation on metaphases to assess sensitivity and specificity; (3) a pilot study using FISH probes on PET; (4) analytical validation using normal and abnormal PET samples to establish a normal reference range or cutoff; and (5) application of the cutoffs to test samples. Although the procedure focuses on dual-color, dual-fusion FISH assays, the same steps could be used for any type of probe. We have described a preclinical validation for probes on paraffin-embedded tissue. ©2008 Elsevier Inc. All rights reserved. [Copyright &y& Elsevier]

Abstract: A panorama of sample preparation methods has been composed from 481 references, with a highlight of some promising methods fast developed during recent years and a somewhat brief introduction on most of the well-developed methods. All the samples were commonly referred to molecular composition, being extendable to particles including cells but not to organs, tissues and larger bodies. Some criteria to evaluate or validate a sample preparation method were proposed for reference. Strategy for integration of several methods to prepare complicated protein samples for proteomic studies was illustrated and discussed. [Copyright &y& Elsevier]

Abstract: The influence of past depositional environments on the chemistry of sub-fossil Juncus seed coats (testa) from the top 1m (corresponding to ca. 900years of peat accumulation) of a peat bog in the Faroe Islands was examined. The chemistry of the testa of fresh Juncus seeds were characterised using thermally assisted pyrolysis and methylation (THM) in the presence of tetramethyl ammonium hydroxide (TMAH) and ‘type’ compounds were identified, representative of the major chemical groups in the testa (cellulose-related sugars, lignin-related phenolics, fatty acids). The abundance of the ‘type’ compounds in the products from sub-fossil testae (the internal tissues of the seeds do not survive beyond the very early stages of decomposition) was then quantified at contiguous 1cm depth intervals. Major losses of C18 unsaturated fatty acid methyl esters and sugars were associated with the fresh to sub-fossil transition at ca. 7cm depth. The preservation of the phenolic ferulic acid in the seed testa appears to be favoured by the input of small basaltic particles from the nearby stream channel. The mechanism by which inwash of inorganic material may be responsible for the improved chemical preservation of the Juncus seed testa is, however, unclear. The sugars were easily metabolised by microorganisms under aerobic conditions of low water table and preserved under anoxic conditions with high water table, suggesting that a drier mire surface may result in the more efficient depletion of polysaccharides and cellulose during the initial stage of decomposition in the acrotelm. [Copyright &y& Elsevier]

Background: Techniques to preserve the sub-valvular apparatus in order to reduce morbidity and mortality following mitral valve replacement have been frequently reported. However, it is uncertain what impact sub-valvular apparatus preservation techniques have on long-term outcomes following mitral valve replacement. This study investigated the effect of sub-valvular apparatus preservation on long-term survival and quality of life following mitral valve replacement. Methods: A microsimulation model was used to compare long-term survival and quality-adjusted life years following mitral valve replacement after conventional valve replacement and sub-valvular apparatus preservation. Probabilistic sensitivity analysis and alternative analysis were performed to investigate uncertainty associated with the results. Results: Our Analysis suggests that patients survive longer if the sub-valvular apparatus are preserved (65.7% SD 1.5%, compared with 58.1% SD 1.6% at 10 years). The quality adjusted life years gained over a 10 year period where also greater after sub-valvular apparatus preservation. (6.54 QALY SD 0.07 QALY, compared with 5.61 QALY, SD 0.07 QALY). The superiority of preservation techniques was insensitive to patient age, parameter or model uncertainty. Conclusion: This study suggests that long-term outcomes may be improved when the sub-valvular apparatus are preserved. Given the lack of empirical data further research is needed to investigate health-related quality of life after mitral valve replacement, and to establish whether outcomes differ between preservation techniques. [ABSTRACT FROM AUTHOR]

Abstract: An analysis of the protein profiles of intact worms and isolated tissues of adult male and female Toxocara canis worms was conducted. Soluble proteins recovered from homogenized whole specimens and dissected tissues (body wall, reproductive tract, esophagus and intestine) of T. canis adults from several different canine hosts were separated by size using gradient sodium dodecyl sulfate electrophoresis (SDS-PAGE) and visualized with silver staining. SDS-PAGE profiles of worms from different hosts were found to be virtually identical irrespective of sex or tissue type. Recovered proteins ranged in size from 3.4 to 325kDa. As expected, variations existed between the protein profiles of different body tissues, with only slight variations between the sexes. The largest number of recovered proteins was present in the female reproductive tract extracts. [Copyright &y& Elsevier]

Abstract: We have cloned a novel KRAB-related zinc finger gene, ZNF307, encoding a protein of 545aa. ZNF307 is conserved across species in evolution and is differentially expressed in human adult and fetal tissues. The fusion protein of EGFP-ZNF307 localizes in the nucleus. Transcriptional activity assays show ZNF307 suppresses transcriptional activity of L8G5-luciferase. Overexpressing ZNF307 in different cell lines also inhibits the transcriptional activities of p53 and p21. Moreover, ZNF307 works by reducing the p53 protein level and p53 protein reduction is achieved by increasing transcription of MDM2 and EP300. ZNF307 might suppress p53–p21 pathway through activating MDM2 and EP300 expression and inducing p53 degradation. [Copyright &y& Elsevier]

Abstract: Recruiting Akt to the membrane-bound phosphatidylinositol (3,4,5) trisphosphate (PIP3) is required for Akt activation. While PI3 kinase (PI3K) produces PIP3, PTEN dephosphorylates the 3-position phosphate from PIP3, thereby directly inhibiting Akt activation. PTEN is the dominant PIP3 phosphatase, as knockdown of PTEN results in increases in Akt activation in mice. The PTEN tumor suppressor gene is frequently mutated in a variety of human cancers, consistent with an inverse correlation between levels of the PTEN protein and Akt activation. We have examined PTEN expression and Akt activation in 35 primary clear cell renal cell carcinomas RCCs (ccRCCs) and 9 papillary RCCs (pRCCs) and their respective non-tumor kidney tissues. The PTEN protein was reduced in 16 ccRCCs (16/35=45.7%) and 8 pRCCs (8/9=88.9%). In these RCCs, 25.0% (4/16) of ccRCCs and 25.0% (2/8) of pRCCs expressed elevated Akt activation. 19 ccRCCc (19/35=54.3%) expressed comparable or higher levels of PTEN. Of these ccRCCs, 31.6% (6/19) showed increases in Akt activation. As PTEN dominantly inhibits Akt activation, the coexistence of high levels of the PTEN protein with enhanced Akt activation suggests the existence of novel mechanisms which attenuate PTEN function in ccRCC. These mechanisms may reduce PTEN function or increase PIP3 production. [Copyright &y& Elsevier]

Abstract: In eukaryotes, mitogen-activated protein kinases (MAPKs) play important roles in various developmental processes and in environmental stress responses. Here, we show that alternative splicing of the OsBWMK1, a member of the rice MAPK family, generates three transcript variants, OsBWMK1L, OsBWMK1M, and OsBWMK1S. The OsBWMK1L transcript variant was highly and constitutively expressed in all rice tissues tested and its expression was not altered by various stress conditions, whereas OsBWMK1M and OsBWMK1S were normally expressed at low levels but were induced by various stresses. A transient expression assay demonstrated that OsBWMK1L::GFP and OsBWMK1M::GFP were predominantly localized in the cytoplasm, whereas most OsBWMK1S::GFP was localized in the nucleus. Moreover, treatment with defense signaling related molecules, such as H2O2 and SA, induced translocation of OsBWMK1 isoforms from the cytoplasm to the nucleus. Thus, our results suggest that alternative splicing of OsBWMK1 generates three different transcript variants that produce proteins with different subcellular localizations. [Copyright &y& Elsevier]

Abstract: The objective of this study was to investigate the level of expression of five cytokines in four different articular tissues from the joints of dogs with and without osteoarthritis (OA). Articular tissues were harvested from the stifle (fat, cranial cruciate ligament, synovial membrane) or hip (articular cartilage) from eight dogs with OA secondary to cranial cruciate ligament disease (stifle) or hip dysplasia (hip), undergoing routine surgical treatment for the condition, and from five dogs euthanatized without orthopaedic disease. The mRNA transcript numbers for interleukin-1β (IL-1β), interleukin-6 (IL-6), interleukin-8 (IL-8), interleukin-10 (IL-10) and interleukin-17 (IL-17) were determined by quantitative real-time reverse transcription polymerase chain reaction (RT-qPCR). Increased expression of IL-1β, IL-6 and IL-10 in OA synovial membrane, increased expression of IL-1β and IL-6 in ruptured (OA) ligament, and reduced expression of IL-8 in OA synovial membrane were identified. Cytokine expression was detected in multiple tissues within the articular joint, but differential expression in OA was detected primarily in the synovial membrane and cranial cruciate ligament. [Copyright &y& Elsevier]

Focuses on the late complications of arterial grafts. Complications associated with the insertion of vascular grafts; Causes of anastomotic aneurysms; Factors to increase survival of grafts.

A case of coarctation of the abdominal aorta, diagnosed as such preoperatively and treated with a homologous arterial graft, preserved for 42 days, is presented. Its functioning had been shown by oscillometry; nevertheless this therapy did not have any repercussion on the generalized hypertensive picture, rather a worsening of the renal function was observed. [ABSTRACT FROM AUTHOR]

The article presents an opinion on the use of hypogastric branch device during endovascular abdominal aortic aneurysm repair with iliac aneurysms. There are benefits of preserving an internal iliac artery. The hypogastric branch devices was successful in terms of maintaining a patent branch. The application of this approach, however, is a challenge for physicians.

Immunotoxicology has developed into an integral regulatory requirement of the toxicological assessment of xenobiotics. Enhanced pathological assessment of tissues can provide genuine insight into perturbations of lymphoid cell populations. To facilitate this we have endeavoured to develop a panel of immunohistochemical techniques to demonstrate T-cells and T-cell subsets in formalin-fixed paraffin-embedded rat lymphoid tissues. We were successful in developing methods for CD3 and CD8 but failed to arrive at a satisfactory technique for the direct demonstration of CD4 in these tissues. Taking the assumption that the majority of mature T-cells are either CD4+ or CD8+ we have combined our methods for CD3 and CD8 in a novel dual-labelling IHC method to simultaneously demonstrate CD3, CD8 and, by implication, CD4. [Copyright &y& Elsevier]

In developmental toxicity studies, the investigation of soft tissues from rat fetuses is routinely performed using Wilson''s free hand razor cross sectioning technique. The unstained slices are investigated with a stereomicroscope for developmental variations or malformations. However, for some findings the correlation with tissue structures or their categorization may remain equivocal based on this technique. Histopathology may then be used for further clarification since the slices are prefixed in a conventional fixative (e.g. Davidson''s solution) and thus give good technical results when paraffin histotechnique is applied. Examples of the usefulness of the combination of Wilson slices and histopathology are presented. A cyst-like structure at the mouth floor proved to be part of the oral cavity and was hence no abnormal finding. A case of enlarged laryngeal lumen could be traced back by histology to a differing section plane. In the eyes, retinal folding as a developmental anomaly could be distinguished from artificial retinal detachment and folding. These examples show that in developmental toxicity studies, histopathology may be valuable for the differentiation between technical artifacts and spontaneous or induced changes in soft tissues. [Copyright &y& Elsevier]