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Multiplexed 3D atlas of state transitions and immune interaction in colorectal cancer. Cell 2023; 186:363-381.e19. [PMID: 36669472 PMCID: PMC10019067 DOI: 10.1016/j.cell.2022.12.028] [Citation(s) in RCA: 55] [Impact Index Per Article: 55.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2021] [Revised: 09/26/2022] [Accepted: 12/16/2022] [Indexed: 01/20/2023]
Abstract
Advanced solid cancers are complex assemblies of tumor, immune, and stromal cells characterized by high intratumoral variation. We use highly multiplexed tissue imaging, 3D reconstruction, spatial statistics, and machine learning to identify cell types and states underlying morphological features of known diagnostic and prognostic significance in colorectal cancer. Quantitation of these features in high-plex marker space reveals recurrent transitions from one tumor morphology to the next, some of which are coincident with long-range gradients in the expression of oncogenes and epigenetic regulators. At the tumor invasive margin, where tumor, normal, and immune cells compete, T cell suppression involves multiple cell types and 3D imaging shows that seemingly localized 2D features such as tertiary lymphoid structures are commonly interconnected and have graded molecular properties. Thus, while cancer genetics emphasizes the importance of discrete changes in tumor state, whole-specimen imaging reveals large-scale morphological and molecular gradients analogous to those in developing tissues.
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Abstract
The imminent release of tissue atlases combining multi-channel microscopy with single cell sequencing and other omics data from normal and diseased specimens creates an urgent need for data and metadata standards that guide data deposition, curation and release. We describe a Minimum Information about highly multiplexed Tissue Imaging (MITI) standard that applies best practices developed for genomics and other microscopy data to highly multiplexed tissue images and traditional histology.
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Human model of burn injury that quantifies the benefit of cooling as a first aid measure. Br J Surg 2019; 106:1472-1479. [PMID: 31441049 DOI: 10.1002/bjs.11263] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2019] [Revised: 03/18/2019] [Accepted: 05/13/2019] [Indexed: 02/11/2024]
Abstract
BACKGROUND Burn injuries are a major cause of morbidity and mortality worldwide. Cooling is widely practised as a first aid measure, but the efficacy of cooling burns in human skin has not been demonstrated. A safe, consistent, ethically acceptable model of burning and cooling in live human skin in vivo was developed, and used to quantify the effects of cooling. METHODS Novel apparatus was manufactured to create and cool burns in women who were anaesthetized for breast reconstruction surgery using a deep inferior epigastric artery perforator flap. Burns were excised between 1 and 3 h after creation, and analysed using histopathological assessment. RESULTS All 25 women who were approached agreed to take part in the study. There were no adverse events. Increased duration of contact led to increased burn depth, with a contact time of 7·5 s at 70°C leading to a mid-dermal burn. Burn depth progressed over time following injury, but importantly this was modified by cooling the burn at 16°C for 20 min. On average, cooling salvaged 25·2 per cent of the dermal thickness. CONCLUSION This study demonstrated the favourable effects of cooling on human burns. Public heath messaging should emphasize cooling as first aid for burns. This model will allow analysis of the molecular effects of cooling burns, and provide a platform for testing novel therapies aimed at reducing the impact of burn injury.
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283 An Epidemiological Study of First Aid Techniques for Pediatric Burns in Different Ethnic Groups and an Analysis of Outcomes. J Burn Care Res 2018. [DOI: 10.1093/jbcr/iry006.205] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
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Abstract
Aims and methodTo compare an existing crisis resolution service with a new crisis resolution team (CRT) in Wales. The impact of the new team was measured by changes in bed days and admissions. A random sample of patients from each service was assessed for service satisfaction, social functioning and quality of life after first presentation.ResultsThe total number of bed days was reduced following the introduction of the new CRT (27.3%). The frequency and duration of compulsory admissions increased by 31% in the CRT between the first and second years and by 7% in the control service, offset by a greater reduction in informal admissions in the CRT (23.5%) compared with the control group (13.3%); overall bed usage was unchanged. Service satisfaction, social functioning and quality of life showed no important differences between the services.Clinical implicationsCrisis resolution teams may reduce informal admissions in the short term but at the cost of more compulsory admissions later.
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Potential errors in relative dose measurements in kilovoltage photon beams due to polarity effects in plane-parallel ionisation chambers. Phys Med Biol 2016; 61:8395-8407. [DOI: 10.1088/0031-9155/61/23/8395] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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PO-0819: The effect of the flattening filter on detector response in small radiation fields. Radiother Oncol 2015. [DOI: 10.1016/s0167-8140(15)40811-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Abstract
INTRODUCTION Approximately 45,000 women are diagnosed with breast cancer in the UK each year. The success of screening and the introduction of adjuvant therapies have meant that prognosis is improving and an increasing number of patients are seeking reconstruction following mastectomy. The purpose of this study was to evaluate the deep inferior epigastric perforator (DIEP) flap reconstructions performed in Stoke Mandeville Hospital and, through analysis of complications, detail the evolution of the current care pathway. METHODS A retrospective analysis was performed of all the DIEP flap reconstructions performed by the senior author (MT) between July 2003 and December 2010. RESULTS Overall, 159 flaps were performed on 141 patients (including 36 bilateral flaps). The average patient age was 49 years (range: 28-70 years) and 13% of flaps were risk reducing for BRCA1/2. Twenty-six per cent of patients suffered one or more complication post-operatively, including systemic complications (pulmonary embolism 2%) and flap specific complications (partial flap necrosis 9%, reanastomosis 3%, fat necrosis 9%). Seventy-four per cent had further elective operations including nipple reconstruction (72%), contralateral breast reduction (36%) and scar revision (21%). CONCLUSIONS DIEP flaps are a safe and reliable option for breast reconstructions. This series illustrates the significant leaning curve, with complications, operative time and ischaemic time reducing through the series and post-operative haemoglobin increasing. The complications experienced in this series of 159 flaps with no total flap loss provide the framework for the evolution of the current care pathway including pre-operative imaging, peri-operative deep vein thrombosis prophylaxis and analgesia.
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Two millimetre biopsy punch: a painless and practical instrument for evacuation of subungual haematomas in adults and children. J Hand Surg Eur Vol 2011; 36:615-7. [PMID: 21724686 DOI: 10.1177/1753193411414629] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
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The organ donor crisis: the missed organ donor potential from the accident and emergency departments. Transplant Proc 2008; 40:1008-11. [PMID: 18555101 DOI: 10.1016/j.transproceed.2008.03.059] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
The critical shortage of cadaveric donor organs for transplant purposes is a worldwide concern. The disparity between the number of cadaveric organs donated for transplant purposes and those patients awaiting transplant operations continues to widen. This article reports on the findings of an audit of deaths undertaken in 10 accident and emergency (A&E) departments in North Thames region, UK. The audit itself was borne out of informal anecdotal accounts from colleagues working in the A&E department who suggested that there was a potential pool of organ and tissue donors that were not being realized. The article discusses how those audit findings helped shape the current A&E education strategy in the North Thames region. The result has been that the North Thames region has seen a dramatic increase in the number of referrals from the A&E departments, resulting in solid organ transplantation. Although the results are very encouraging, the program is still very much in its infancy and a long way from the desired 100% referral rate. In order to maximize the number of organs from the potential donor pool, the transplant community needs to focus more attention toward donation from the A&E departments.
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Too close for comfort: accidental burn following subcutaneous mastectomy and immediate implant reconstruction. J R Soc Med 2008; 101:39-40. [PMID: 18263913 DOI: 10.1258/jrsm.2007.070032] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
We report a case of an accidental burn from a self-applied heat pack following subcutaneous mastectomy and implant reconstruction. Such patients are at increased risk of accidental burns not only due to loss of protective sensation, but also because of the thinner, less vascular overlying skin. We have changed our practice so that all patients undergoing breast reconstructive surgery are warned postoperatively to protect the skin from externally applied heat sources.
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Human Delta1-pyrroline-5-carboxylate synthase: function and regulation. Amino Acids 2008; 35:665-72. [PMID: 18401542 DOI: 10.1007/s00726-008-0075-0] [Citation(s) in RCA: 78] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2007] [Accepted: 03/24/2008] [Indexed: 11/25/2022]
Abstract
Mammalian Delta(1)-pyrroline-5-carboxylate synthase (P5CS) is a bifunctional ATP- and NAD(P)H-dependent mitochondrial enzyme that catalyzes the coupled phosphorylation and reduction-conversion of L: -glutamate to P5C, a pivotal step in the biosynthesis of L: -proline, L: -ornithine and L: -arginine. Previously, we reported cloning and characterization of two P5CS transcript variants generated by exon sliding that encode two protein isoforms differing only by a two amino acid-insert at the N-terminus of the gamma-glutamyl kinase active site. The short form (P5CS.short) is highly expressed in the gut and is inhibited by ornithine. In contrast, the long form (P5CS.long) is expressed ubiquitously and is insensitive to ornithine. Interestingly, we found that all the established human cell lines we have studied expressed P5CS.long but not P5CS.short. In addition, expression of P5CS.long can be modulated by hormones: downregulation by hydrocortisone and dexamethasone and upregulation by estradiol, for example. Using a quantitative proteomic approach, we showed that P5CS.long is upregulated by p53 in p53-induced apoptosis in DLD-1 colorectal cancer cells. Functional genomic analysis confirmed that there are two p53-binding consensus sequences in the promoter region and in the intron 1 of the human P5CS gene. Interestingly, overexpression of P5CS by adenoviruses harboring P5CS.long or P5CS.short in various cell types has no effect on cell growth or survival. It would be of importance to further investigate the role of P5CS as a p53 downstream effector and how P5CS.short expression is regulated by hormones and factors of alternative splicing in cells isolated from model animals.
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Ischaemic preconditioning of the liver before transplantation. S AFR J SURG 2007; 45:122-126. [PMID: 18069578] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
PURPOSE Assessment of the effect of a short ischaemic time prior to liver transplantation on the liver graft. METHODS White X Landrace pigs (N=10) were subjected to liver transplantation. Before being removed from the donor animal, the livers were randomised into two groups: group 1--pre-procurement ischaemia (15 minutes' temporary arrest of portal venous and hepatic arterial inflow to the liver, followed by reperfusion of these vessels for a period of 15 minutes); group 2--no prior inflow occlusion (control group). In group 1 a spleno-jugular bypass was established to prevent venous congestion, portal venous hypertension, intestinal oedema and bacterial translocation. The livers were perfused with Eurocollins solution (4 degrees C), after which they were stored on ice for a period of 3 hours' cold ischaemic time. Hepatocellular injury was assessed according to liver cell function tests (aspartate aminotransferase, AST), biochemical indicators of reperfusion injury (malondialdehyde) and histopathology. RESULTS There was a significant rise of AST in both groups 1 hour after transplantation (from 51 +/- 27 IU/l to 357 +/- 152 IU/l in group 1 and from 29 +/- 10 IU/l to 359 +/- 198 IU/l in group 2). AST levels were marginally lower in group 1 at 2 and 4 hours after transplantation. There was also a rise in malondialdehyde levels in both groups at 5, 20, 40 and 60 minutes after transplantation. Levels of malondialdehyde were lower in the primed group at 5, 20 and 40 minutes, while the levels at 60 minutes after transplantation were comparable. Histological changes, as measured by vacuolisation, neutrophil infiltration and hepatic cell necrosis, were less in livers transplanted after ischaemic preconditioning, although the difference was not significant. CONCLUSIONS Ischaemic preconditioning of the donor liver seems to decrease hepatocellular damage, reperfusion injury and histological changes in the liver after transplantation. Further studies with larger numbers are indicated.
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Biochemical and immunohistochemical characterisation of mucins in 8 cases of colonic disease--a pilot study. S AFR J SURG 2007; 45:18-23. [PMID: 17969773] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
OBJECTIVES To characterise mucins in cancer of the colon and compare these with controls using stringent biochemical measures to avoid endogenous proteolysis. DESIGN Crude mucus scrapings were collected from 12 specimens obtained by colectomy. Specimens from 3 traumatic colectomies and 1 sigmoid volvulus were used as controls, and compared with 6 specimens from colons resected for adenocarcinoma and 2 irradiated colons. SUBJECTS The median age of the 4 female patients was 76 years (range 49 - 82 years), and of the 8 male patients 46.5 years (range 16 - 74 years). RESULTS AND CONCLUSIONS The crude mucus scrapings in the 9 specimens ranged in weight from 353 mg to 7 697 mg (median 4 928 mg). The median of purified mucin in the 9 specimens was 0.72 microg/mg wet weight of scraped material. Eight samples gave non-extractable pellet material, and were treated with DTT to reduce disulphide bonds for further analysis. One of these 8 pellets was resistant to reduction and had to be digested with papain before analysis. Only 5 of these pellets had mucin. Gel filtration and SDS-PAGE (sodium dodecyl sulphate polyacrylamide gel electrophoresis) analysis revealed different populations of mucin based on size and extent of degradation. Western blotting and immunohistochemical analysis confirmed the presence of MUC2 in all samples, MUC5AC in 2 and MUC5B in 5 diseased specimens. Immunohistochemical analysis showed that there was no MUC1 in the normal specimens, MUC1 apoprotein (MUC1 core) in 2 cancer specimens and MUC1 in 1 cancer specimen. Histochemical analysis showed that normal tissue expressed neutral and acidic mucins and diseased specimens predominantly expressed acidic mucins. The electrophoretic behaviour of MUC2 in sigmoid volvulus was different from that in cancer of the colon.
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Abstract
Besides its potent immunosuppressive properties, rapamycin also has antitumor and antifungal effects. Rapamycin also inhibits the proliferation of fibroblasts and therefore may impair the healing of various tissues. We investigated the effect of rapamycin on the healing of the bile duct anastomosis. The study was undertaken in pigs that were subjected to a laparotomy under general anesthesia. The bile duct was mobilized and divided and immediately reanastomosed. The animals were randomly allocated to receive either rapamycin or placebo. The animals were sacrificed on the postoperative day 5, then the biliary anastomosis was excised and used to determine the tensile strength, hydroxyproline levels, and the histological changes. The tensile strength and the hydroxyproline levels in the biliary anastomosis were lower in the animals treated with rapamycin. The liver function tests were normal. These studies show that rapamycin may impair the healing of the biliary anastomosis.
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Restoration of liver mass after partial hepatectomy--implications for living donor liver transplantation. S AFR J SURG 2005; 43:70-2. [PMID: 16180390] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
In living donor liver transplantation, the recipient liver undergoes more rapid regeneration than the remnant liver in the donor. In this study we investigated the factors which may be responsible for the difference in the regenerative response between the donor and the recipient. Long Evans rats were subjected to either partial hepatectomy (PH) or sham operation (SH) and were treated with liver cytosol (C) and cyclosporine (Cy). The rats were sacrificed at 24, 48, 72 and 96 hours and 1 and 2 weeks postoperatively. The livers were removed to determine the liver weight/body weight (LW/BW) ratio and the mitotic index. The mitotic index, serum aspartate transferase (AST) and serum alanine transferase (ALT), although unchanged in the SH groups, were increased in the rats treated with PH + C + Cy, and were greater than after PH only. However LW/BW ratios increased after PH but had returned to preoperative levels by 2 weeks. The changes in LW/BW ratio were not modified by the cytosol or cyclosporine.
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Abstract
Rapamycin is a potent immunosuppressive agent that also inhibits fibroblastic activity and therefore may affect the healing of various tissues. The aim of this study was to investigate the effect of rapamycin on wound healing and the healing of the ureteric anastomosis. Large White/Landrace pigs were subjected to a laparotomy and division and immediate anastomosis of the ureter. The animals were randomly allocated to receive either rapamycin or placebo. The animals were sacrificed on postoperative day 5, and strips of the skin and fascia closure and the ureteric anastomosis excised and used to determine the tensile strength, hydroxyproline levels, and histological changes. The tensile strength and the hydroxyproline levels in the ureter and fascia were lower in the rapamycin-treated animals. There was no difference in the tensile strength in the skin, although the hydroxyproline levels were lower. This study shows that healing of the ureteric anastomosis and fascia and skin closure may be impaired by rapamycin.
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Histological assessment after different methods of reperfusion following liver transplantation. S AFR J SURG 2002; 40:95-8. [PMID: 12387218] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/26/2023]
Abstract
INTRODUCTION Preservation-reperfusion injury is a major cause of graft failure after liver transplantation. This injury refers to a variety of insults after reperfusion of the graft, independent of technical errors, vascular problems, immunological reactions or infection. Significant injuries occur during the period of cold preservation. Loss of sinusoidal endothelial attachments to the underlying extracellular matrix results in loss of the normal antithrombogenic milieu. Reperfusion with recipient blood results in platelet aggregation and neutrophil sludging in all areas of denudation, preventing adequate reoxygenation. Early histopathological findings in biopsy specimens can predict poor graft outcome. OBJECTIVE To analyse the effect of early rearterialisation on histological findings of the liver biopsies after liver transplantation. METHODS Twenty young Large White X Landrace pigs (weight 22-28 kg) were subjected to orthotopic liver transplantation. Livers were stored in Eurocollins solution for 3 hours on ice and the animals were randomised into four different groups of increasingly early arterialisation. Groups were aligned from delayed rearterialisation (group 1) to early rearterialisation (group 4). Biopsies were taken before and after cold storage, as well as 1 hour post transplantation. RESULTS Results show that both hepatocyte vacuolisation and neutrophil infiltration were significantly reduced in group 4 (early rearterialisation), compared with groups 1, 2 and 3. Single cell necrosis and group cell necrosis of the hepatocytes were both significantly reduced in groups 3 and 4 compared with groups 1 and 2 (early venous reperfusion). CONCLUSION This study demonstrates that early rearterialisation is associated with a decrease in early histopathological changes in the transplanted pig liver.
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Outcomes of family-centered residential treatment. CHILD WELFARE 2001; 80:351-379. [PMID: 11380046] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
This article describes a family-centered residential treatment model and presents results from a quasiexperimental study examining its effectiveness in achieving permanency outcomes for children. Greater postdischarge stability was achieved for participants in the family-centered program than in the agency's standard residential treatment service. Implications for child welfare policy and practice are highlighted.
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Abstract
BACKGROUND Initially, preservation solutions were developed to maintain cell function of the transplanted organs. However, recently developed preservation solutions also contain a variety of substances to reduce the reperfusion injury. AIM To study the effect of three different preservation solutions on the liver cell injury, endothelial cell function and reperfusion injury after liver transplantation. MATERIAL AND METHODS Large White X Landrace pigs of either sex were subjected to orthotopic liver transplantation. Donor livers were flushed and stored in University of Wisconsin Solution, Eurocollins Solution or Celsior Solution for 3 hours. Blood samples were taken at various times post transplantation for assessment of aspartate aminotransferase, hyaluronic acid, malondialdehyde and Vitamin A levels. RESULTS Serum aspartate aminotransferase levels were lower in the livers preserved in the Wisconsin solution. Plasma malondialdehyde levels were lower and serum Vitamin A levels were higher in the livers preserved in Celsior solution. Serum hyaluronic acid levels increased after liver transplantation but were similar with all three solutions. CONCLUSIONS There was less hepato-cellular injury in the livers preserved in Wisconsin solution and less reperfusion injury with the Celsior solution. The endothelial cell injury was similar with all three solutions.
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Effect of early arterialization of the porcine liver allograft on reperfusion injury, hepatocellular injury, and endothelial cell dysfunction. Liver Transpl 2001; 7:32-7. [PMID: 11150419 DOI: 10.1053/jlts.2001.20774] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The conventional technique of liver transplantation involves the initial perfusion of the graft with portal blood. However, recent evidence suggests that initial arterialization of the graft may be better. The aim of this study is to evaluate the timing of arterialization on reperfusion injury, hepatocellular injury, and endothelial cell function after liver transplantation. Large white X Landrace pigs (n = 24) were subjected to orthotopic liver transplantation. The animals were randomly assigned to 4 groups, ranging from late arterialization (60 minutes after portal reperfusion) to early rearterialization (20 minutes before portal reperfusion). Aspartate aminotransferase levels continued to increase 4 hours posttransplantation in group 1 (late arterialization), but remained stable after 1 hour posttransplantation in group 4 (early rearterialization). Levels of malondialdehyde doubled in all groups after portal reperfusion with the exception of group 4, in which the liver received arterial blood before portal reperfusion. Vitamin A levels decreased in all groups after revascularization, but the decrease was more pronounced and prolonged in groups 1 and 2 (late arterialization) compared with groups 3 and 4 (early rearterialization). Hyaluronic acid levels continued to increase in all groups until 1 hour posttransplantation except in group 4, in which the level decreased from 20 minutes posttransplantation. Results of this study show that early rearterialization is associated with less hepatocellular damage, less reperfusion injury, and improved liver endothelial cell function. In conclusion, our results indicate that early rearterialization of the graft is beneficial to the transplanted liver.
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Assessment of the value of the vertebral heart scale in the radiographic diagnosis of cardiac disease in dogs. Vet Rec 2000; 146:687-90. [PMID: 10887980 DOI: 10.1136/vr.146.24.687] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
In order to assess the influence of the vertebral heart scale (VHS) on the accuracy of the radiographic diagnosis of cardiac disease, thoracic radiographs of 50 dogs with proven cardiac disease, 26 with other thoracic diseases, and 50 with no clinical signs of cardiovascular or respiratory disease were mixed and examined by three independent, blinded observers chosen to represent a range of radiographic abilities. They first examined all the radiographs without making measurements of VHS and made a diagnosis. They then re-examined the radiographs, and measured VHS on both lateral and dorsoventral or ventrodorsal radiographs before again recording a diagnosis without reference to their original diagnoses. For all the observers, the dogs with cardiac disease had a higher mean VHS than the normal dogs. A VHS over 10.7 on the lateral radiograph was a moderately accurate sign of cardiac disease. The observers' accuracy of diagnosis did not change significantly as a result of using VHS as an adjunct to a subjective assessment of the radiographs.
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The changes in circulating hepatocyte growth factor after partial hepatectomy in the baboon. S AFR J SURG 1999; 37:31-7. [PMID: 10450655] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/13/2023]
Abstract
There is no established model of regenerative liver resection in the baboon, and no study comparing the circulating hepatocyte growth factor (HGF) response with the DNA synthetic response after liver resection. A mean 20% partial hepatectomy (PH) was performed in 19 baboons and a sham operation comprising liver mobilisation only was performed in 20 baboons. Blood HGF levels were measured up to 5 days after either procedure, using the human HGF enzyme-linked immunosorbent assay (ELISA) kit (Otsuka, Japan). The white cell count (WCC), aspartate transaminase (AST) and bilirubin were also measured. Liver regeneration, reflected by an increase in DNA synthesis, was determined from serial liver biopsies in 23 baboons, using a tritiated thymidine assay of liver thymidine kinase (TK). Liver resection and WCC had a significant influence on circulating HGF levels. There was a linear relationship between WCC and circulating HGF levels, which was independent of PH. For a constant value of WCC, resection produced a peaking of HGF over time, with the maximal levels occurring between 2 and 3 days, compared with the linear response in HGF in sham-operated baboons. Liver damage, as reflected by AST levels, was found to have no significant influence on circulating HGF levels. The 20% PH produced a significant increase in liver TK, with maximum levels evident between 2 and 4 days. Accordingly in this baboon model of PH the increase in biologically active, circulating HGF preceded the increase in liver DNA synthesis over 5 days. This observation supports the role of HGF in hepatocyte proliferation and as an initiator of liver regeneration, and suggests that further investigation into the potential endocrine action of HGF could be studied in this established liver regenerative primate model.
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Abstract
The combination of two-dimensional polyacrylamide gel electrophoresis (2-D PAGE), computer image analysis and several protein identification techniques allowed the Escherichia coli SWISS-2DPAGE database to be established. This is part of the ExPASy molecular biology server accessible through the WWW at the URL address http://www.expasy.ch/ch2d/ch2d-top.html . Here we report recent progress in the development of the E. coli SWISS-2DPAGE database. Proteins were separated with immobilized pH gradients in the first dimension and sodium dodecyl sulfate-polyacrylamide gel electrophoresis in the second dimension. To increase the resolution of the separation and thus the number of identified proteins, a variety of wide and narrow range immobilized pH gradients were used in the first dimension. Micropreparative gels were electroblotted onto polyvinylidene difluoride membranes and spots were visualized by amido black staining. Protein identification techniques such as amino acid composition analysis, gel comparison and microsequencing were used, as well as a recently described Edman "sequence tag" approach. Some of the above identification techniques were coupled with database searching tools. Currently 231 polypeptides are identified on the E. coli SWISS-2DPAGE map: 64 have been identified by N-terminal microsequencing, 39 by amino acid composition, and 82 by sequence tag. Of 153 proteins putatively identified by gel comparison, 65 have been confirmed. Many proteins have been identified using more than one technique. Faster progress in the E. coli proteome project will now be possible with advances in biochemical methodology and with the completion of the entire E. coli genome.
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Abstract
Genome sequences are available for increasing numbers of organisms. The proteomes (protein complement expressed by the genome) of many such organisms are being studied with two-dimensional (2D) gel electrophoresis. Here we have investigated the application of short N-terminal and C-terminal sequence tags to the identification of proteins separated on 2D gels. The theoretical N and C termini of 15, 519 proteins, representing all SWISS-PROT entries for the organisms Mycoplasma genitalium, Bacillus subtilis, Escherichia coli, Saccharomyces cerevisiae and human, were analysed. Sequence tags were found to be surprisingly specific, with N-terminal tags of four amino acid residues found to be unique for between 43% and 83% of proteins, and C-terminal tags of four amino acid residues unique for between 74% and 97% of proteins, depending on the species studied. Sequence tags of five amino acid residues were found to be even more specific. To utilise this specificity of sequence tags for protein identification, we created a world-wide web-accessible protein identification program, TagIdent (http://www.expasy.ch/www/tools.html), which matches sequence tags of up to six amino acid residues as well as estimated protein pI and mass against proteins in the SWISS-PROT database. We demonstrate the utility of this identification approach with sequence tags generated from 91 different E. coli proteins purified by 2D gel electrophoresis. Fifty-one proteins were unambiguously identified by virtue of their sequence tags and estimated pI and mass, and a further 11 proteins identified when sequence tags were combined with protein amino acid composition data. We conlcude that the TagIdent identification approach is best suited to the identification of proteins from prokaryotes whose complete genome sequences are available. The approach is less well suited to proteins from eukaryotes, as many eukaryotic proteins are not amenable to sequencing via Edman degradation, and tag protein identification cannot be unambiguous unless an organism's complete sequence is available.
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Candidal colonization and oral candidiasis in patients undergoing oral and pharyngeal radiation therapy. ORAL SURGERY, ORAL MEDICINE, ORAL PATHOLOGY, ORAL RADIOLOGY, AND ENDODONTICS 1997; 84:149-53. [PMID: 9269016 DOI: 10.1016/s1079-2104(97)90061-5] [Citation(s) in RCA: 104] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
OBJECTIVES Radiotherapy-induced hyposalivation encourages oral candidal colonization that often leads to oral/pharyngeal candidiasis. The purpose of this study was to quantitate oral candidal colonization, assess signs, symptoms, and response to antifungal management, speciate Candida, and evaluate the influence of smoking and dentures. STUDY DESIGN Forty-six patients undergoing radiation therapy for oral/pharyngeal squamous cell carcinoma were evaluated clinically and by Candidal cultures before, during, and after irradiation. RESULTS All patients complained of progressive xerostomia. There was a significant increase in the prevalence of positive candidal cultures (P = < 0.0001): baseline 43%, completion of radiotherapy 62%, and follow-up timepoint 75%. Smoking and denture wearing were not statistically significant risk factors for increased candidal colonization (p = 0.085 and p = 0.420, respectively). Eight patients developed clinical candidiasis. Although five responded clinically to systemic antifungal medication, all follow-up cultures remained positive. Candida albicans was the predominant species at baseline and completion of radiation (85% and 68%, respectively). CONCLUSIONS When salivary glands are included in the field of radiation, xerostomia occurs, causing progressive increases in oral Candida colonization. Because 17.4% developed clinical candidiasis during radiotherapy and the question of fungal resistance remains speculative, a recommendation for the prophylactic use of antifungal medication is unresolved.
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Abstract
The actions of potent mammalian neurotoxins isolated from the venom of two Australian funnel-web spiders were investigated using both electrophysiological and neurochemical techniques. Whole-cell patch clamp recording of sodium currents in rat dorsal root ganglion neurons revealed that versutoxin (VTX), isolated from the venom of Hadronyche versuta, produced a concentration-dependent slowing or removal of tetrodotoxin-sensitive (TTX-S) sodium current inactivation and a reduction in peak TTX-S sodium current. In contrast, VTX had no effect on tetrodotoxin-resistant (TTX-R) sodium currents or potassium currents. VTX also shifted the voltage dependence of sodium channel activation in the hyperpolarizing direction and increased the rate of recovery from inactivation. Ion flux studies performed in rat brain synaptosomes also revealed that robustoxin (RTX), from the venom of Atrax robustus, and VTX both produced a partial activation of 22Na+ flux and an inhibition of batrachotoxin-activated 22Na+ flux. This inhibition of flux through batrachotoxin-activated channels was not due to an interaction with neurotoxin receptor site 1 since [3H]saxitoxin binding was unaffected. In addition, the partial activation of 22Na+ flux was not enhanced in the presence of alpha-scorpion toxin and further experiments suggest that VTX also enhances [3H]batrachotoxin binding. These selective actions of funnel-web spider toxins on sodium channel function are comparable to those of alpha-scorpion and sea anemone toxins which bind to neurotoxin receptor site 3 on the channel to slow channel inactivation profoundly. Also, these modifications of sodium channel gating and kinetics are consistent with actions of the spider toxins to produce repetitive firing of action potentials.
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Changes of fitness during prolonged traiing in Standardbred horses. PFERDEHEILKUNDE 1996. [DOI: 10.21836/pem19960424] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Abstract
Questionnaire data concerning hand preference from the parents of 686 schizophrenic patients were used to test predictions relevant to neurodevelopmental models of schizophrenia. In line with predictions, left-handed patients (n = 94) had a more frequent history of difficult birth, more childhood cognitive and behavioural abnormalities and more persistent auditory hallucinations than did right-handed patients.
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Regeneration after in situ flushing of partially hepatectomised rat livers. S AFR J SURG 1995; 33:78-81. [PMID: 8545730] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The effect of various components of the transplant procedure upon the regenerative process in reduced liver grafts is not known. In this study, partially hepatectomised rat liver remnants were flushed with 5 ml of either Ringer's lactate, Euro Collins solution or University of Wisconsin solution at 4 degrees C and then 5 ml Ringer's lactate at 4 degrees C. After partial hepatectomy alone, the peak increase in thymidine kinase was measured at 24 hours (36,021 +/- 8,060 disintegrations per minute per milligram protein; the mitotic index was 25 +/- 7). In all the groups in which the remnant was flushed, peak thymidine kinase and mitotic index were measured at 48 hours. The pattern of ornithine decarboxylase activity was disorganised in all groups. Flushing of the liver remnant therefore delays the regenerative response by 24 hours. In large animals, including humans, regeneration appears to commence within the first 5 days after resection. A comparable delay doubling this time might coincide with the onset of rejection and further compromise liver function.
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36
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Reconstruction of composite mandibular defects. Plast Reconstr Surg 1995; 95:1127-8. [PMID: 7732131 DOI: 10.1097/00006534-199505000-00037] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
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37
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Right to nurse. Talk about it. Nurs Stand 1995; 9:40-1. [PMID: 7703132 DOI: 10.7748/ns.9.22.40.s47] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
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Abstract
Four cases of ear reduction for congenital macrotia and ear asymmetry are presented. To minimize the visible scarring the technique of helical advancement was used. The indications for this uncommon procedure are discussed with a review of the literature. This simple technique has been effective in achieving the desired reduction, leaving the scar hidden in the eaves of the helix, and we endorse its wider use.
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The effect of administration of FK506 on delayed regeneration in flushed partially hepatectomized livers. Transplantation 1994; 57:655-8. [PMID: 7511255 DOI: 10.1097/00007890-199403150-00003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
It has been shown previously that liver regeneration after partial hepatectomy in rats is delayed if the liver is subjected to either concurrent ischaemia, flushing with cold solution, or grafting. We have shown recently that treatment with CsA preoperatively overcomes the suppressive effect of flushing and returns the regenerative response to a normal time scale. The present study was designed to investigate whether administration of FK506 would also return the observed delayed regenerative response to normal. Long-Evans rats weighing 250-350 g were subjected to standard 68% partial hepatectomy. Group 1 had no further treatment; in group 2, the liver remnant was flushed with 10 ml cold (4 degrees C) Ringers lactate solution, and in group 3, FK506 (1 mg/kg/day) was administered by intramuscular injection for 3 days before the partial hepatectomy and flushing as in group 2; a final dose was given after completion of the procedures. Animals were killed in sets of 6 per group at 4, 24, 48, 72, and 96 hr after surgery and blood samples were taken for measurement of plasma aspartate amino-transferase. Liver biopsies were analyzed for measurement of thymidine kinase and ornithine decarboxylase activity and for counting of mitotic figures. While the highest recorded thymidine kinase activity occurred in group 1 at 24 hr, this was delayed to 48 hr in both group 2 and 3 and counts remained high up to 96 hr in group 3. Mitotic indices were only significantly elevated (compared with group 1 at 96 hr), while ornithine decarboxylase activity did not correlate with these changes being significantly lower than in groups 2 and 3 at 4 hr and in group 3 also at 24 hr. Plasma aspartate aminotransferase was also significantly higher in group 3. It is concluded that the administration of FK506 preoperatively to rats subjected to partial hepatectomy and flushing did not restore the delayed regenerative response to normal but enhanced the response (as measured by thymidine kinase but not by mitotic indices) which commenced at 48 hr and was still present at 96 hr.
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The regenerative response in intact young livers grafted into different sized recipient pigs. J Hepatol 1994; 20:309-10. [PMID: 8006413 DOI: 10.1016/s0168-8278(05)80077-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
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Does liver transplantation in the rat cause a regenerative response. The effect of arterialisation of the graft. HPB SURGERY : A WORLD JOURNAL OF HEPATIC, PANCREATIC AND BILIARY SURGERY 1994; 7:211-7. [PMID: 8155587 PMCID: PMC2423698 DOI: 10.1155/1994/96762] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
This study was conducted to determine the pattern of early regenerative response to orthotopic intact liver transplantation in the rat and to investigate whether the response differed in grafts with or without revascularisation of the arterial bed. Outbred male Long Evans (LE-LE allogeneic, non rejector) rats weighing 300-350g were subjected to orthotopic intact liver allograft using a "sleeve" anastomosis for the hepatic artery. Total warm ischaemia ranged from 19 to 34 minutes and no storage was employed. Comparison was made with a group of control rats which were subjected to 25 minutes total inflow occlusion and regeneration was measured with tissue thymidine kinase (TK) and mitotic figures. Samples were taken at 1, 2, 4, 7, 10 and 20 days post-operatively. Plasma aspartate aminotransferase (AAT) and light microscopy were used to evaluate hepatocyte necrosis. There was a brief sharp increase in TK and AAT in the first 24 hours after sham operation but no appearance of mitotic figures. A similar but more prolonged increase in TK occurred in the arterialized transplant group with the highest levels recorded on day 4. The level remained significantly elevated above pre-operative until 10 days and declined within 20 days. Mitotic figures appeared at 2 days, reached significance at 7 and 10 days and had disappeared by 20 days. The pattern of changes was accentuated in animals in which the artery was not reanastomosed and the increases in TK and AAT were still significant at 20 days. Whilst similar degrees of peri-portal cellular infiltrate occurred in both groups of rats, bile duct proliferation was most obvious in non-arterialized animals.(ABSTRACT TRUNCATED AT 250 WORDS)
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A case for changing the way schizophrenia is conceptualised, using a questionnaire to relatives. Med Hypotheses 1993; 41:195-200. [PMID: 7903114 DOI: 10.1016/0306-9877(93)90229-j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
In view of dissatisfaction among philosophers and many doctors with the DSM III criteria for schizophrenia a new conceptualization is needed. Recent research results showing the complex influences on the development and functions of the brain suggest that the primary problem is a reduced capacity for information processing and not the more obvious symptoms of acute episodes. An analysis of a questionnaire to relatives (members of the National Schizophrenia Fellowship) has been used to illustrate how data from relatives can provide useful indicators of some of the factors such as possible metabolic abnormalities and immune system deficiencies which may contribute to this problem. It is suggested that a broad data-base is needed to study such contributory factors and point the way to forms of treatment which might make lower levels of maintenance neuroleptic medication possible.
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Liver regeneration after hepatic ischemia and reduced liver autotransplantation in the rat. Hepatology 1993; 17:273-9. [PMID: 8428725] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/05/2022]
Abstract
Current knowledge of liver regeneration after reduced liver transplantation is limited. Warm ischemia is one component of the reduced liver transplantation procedure that could have an impact on the regenerative response. To study this effect, we performed partial hepatectomy on male Long-Evans rats, with animals divided into four groups: group 1 underwent partial hepatectomy only; group 2 underwent partial hepatectomy and 40 min of ischemia; group 3 underwent partial hepatectomy, 40 min of ischemia and portocaval shunt surgery; and group 4 underwent partial hepatectomy and orthotopic autograft surgery. Group 5 consisted of sham-operated animals. Animals were killed 4, 24, 48, 72 and 96 hr after surgery. Thymidine kinase activity, mitotic index, a liver mass index and ornithine decarboxylase levels were used as parameters of liver regeneration. Aspartate transaminase was recorded. Maximal thymidine kinase and mitotic index were observed in group 1 animals at 24 hr. In groups 2, 3 and 4 maximal thymidine kinase activity and mitotic activity were observed 24 hr later at 48 hr. The magnitude of the peak response in these groups appeared to correlate with the duration of portal venous occlusion, with greatest increases occurring in those groups where portal stasis was most prolonged. The increase in liver mass for these groups was also delayed with respect to group 1 animals. The anticipated peak in ornithine decarboxylase levels was seen at 4 hr in group 1. The ornithine decarboxylase response in the other groups was disorganized, with delay of the recorded peaks.(ABSTRACT TRUNCATED AT 250 WORDS)
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Abstract
Elevation of serum insulin and plasma glucagon have been reported during and immediately after clinical and experimental liver transplantation and in patients with cirrhosis and surgically created or spontaneous portacaval shunts. There is controversy about the relative roles of portal diversion and impaired liver function in the genesis of these elevated levels of pancreatic hormones. End-to-side portacaval shunt was made in normal pigs which were fitted with catheters which allowed transhepatic sampling during and for 4 hr after the operation. Within 5 min of opening the shunt, there was a sixfold increase in portal venous insulin concentrations but hepatic clearance of insulin and the arterial concentration were unaltered. The increase in insulin was sustained for 2 hr. A twofold increase occurred within 1 hr in portal venous glucagon concentration which appeared to be predominantly of pancreatic origin and which continued for the 4 hr of the study. Hepatic glucose uptake did not occur after portacaval shunting despite levels of glucose elevated two-fold by iv infusion. There were no changes in aspartate aminotransferase, hepatic tissue energy charge, or total adenine nucleotides, suggesting that hepatic function was intact. It is concluded that portal diversion results in an increase in insulin and glucagon secretion and in the absence of hepatic uptake of glucose. This is a novel observation with relevance especially in liver transplantation when portal diversion for at least 1 hr forms part of the procedure.(ABSTRACT TRUNCATED AT 250 WORDS)
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Identification of the loci of the collagen-associated Ehrlich chromogen in type I collagen confirms its role as a trivalent cross-link. Biochem J 1992; 283 ( Pt 1):129-36. [PMID: 1567360 PMCID: PMC1131004 DOI: 10.1042/bj2830129] [Citation(s) in RCA: 64] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Collagenous peptides containing the Ehrlich chromogen (EC) were selectively isolated from a tryptic digest of bovine tendon by coupling to a diazotized polyacrylamide support. The isolated p-phenol-azo-EC peptides were purified and characterized by amino acid and sequence analyses. EC occurred in stoichiometric amounts in trimeric cross-linked chains originating from the known cross-link regions of type-I collagen. The major locus of the EC was alpha 2(I)Hyl-933 x alpha 1(I)Lys(Hyl)-9N x alpha 2(I)Lys(Hyl)-5N but it was also shown to occur at the loci alpha 1(I)Hyl-87 x alpha 1(I)Lys(Hyl)-16C x alpha 1(I)Lys(Hyl)-16C and alpha 1(I)Hyl-930 x alpha 1(I)Lys(Hyl)-9N x alpha 2(I)Lys(Hyl)-5N. After sequence analyses of the C-terminal helical cross-link region alpha 2(I)928-963, corrections are presented for residues 927, 930, 932 and 933 of the bovine alpha 2(I) chain. The collagen-associated EC is postulated to be a trisubstituted pyrrole formed by the reaction of the aldehyde form of a telopeptidyl lysine residue with a bifunctional keto amino cross-link. It is also proposed that when the telopeptidyl lysine residue is hydroxylated the above reaction will result in pyridinoline formation.
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Abstract
It has been suggested recently that patients with fulminant liver failure should be prepared for transplantation by early hepatectomy, yet the acute effects of removal of the liver upon the coagulation profile and certain hormones are not known. This study was conducted on totally hepatectomized pigs that survived up to 27 hr. Measurements were made of serum insulin, plasma glucagon (IRG and GLI), glucose, catecholamines, and the coagulation profile. The increase in serum insulin was directly related to levels of plasma glucose--there was a 100-fold increase in animals with plasma glucose levels greater than 400 mg/100 ml and none when blood glucose was less than 100 mg/100 ml. Plasma glucagon showed a sharp transient increase within 1 hr of hepatectomy and a slow rise thereafter with levels apparently unrelated to serum insulin or plasma glucose. There was a transient increase in plasma adrenaline but a sharp continuous increase in plasma norepinephrine. No changes of note occurred in the coagulation profile--even levels of fibrinogen only declined by 20% in 27 hr. The study has shown that early total hepatectomy is safe as far as changes in coagulation are concerned but changes in serum insulin and especially plasma norepinephrine may be of more significance.
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Energy charge as an indication of liver viability. A comparison of changes in livers that remained intact with those subjected to autografting. Transplantation 1992; 53:540-5. [PMID: 1549844 DOI: 10.1097/00007890-199203000-00009] [Citation(s) in RCA: 28] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
As efforts to assess the viability of liver grafts continue, the recent description of noninvasive measurement by fluorimetry or magnetic resonance spectrometry of adenine nucleotides has brought energy charge into focus again as an index of viability. Many previous studies have been conducted in human donor livers that have clinical relevance but which cannot be standardized, or in rats in which the hepatic artery is not anastomosed. In the present study, pig livers were definitively rendered ischemic for 1 or 2 hr. In one group the livers were then revascularized (intact) while in the other, the livers were removed during the final 20-30 min of the ischemic period and were subjected to autograft. There was a marked difference in survival between the intact and the autograft groups. One hour of ischemia in the intact group was associated with survival comparable to that of autograft controls (8-100 days); 2 hr of ischemia caused shortened survival, ranging from 2 to 18 days. In the recipients of autografts, survival after 1 hr of ischemia ranged from 3 to 16 days; after 2 hr of ischemia no autograft recipient survived overnight. The energy charge returned to the preoperative level after 2 hr of ischemia in both intact and autograft groups. The concentrations remained depressed after 2 hr of ischemia in autografted animals, thus being associated with survival. However, the patterns of total adenine nucleotide and adenosine triphosphate were not always similar to those of energy charge. The concentrations of aspartate aminotransferase were similarly elevated in all ischemic groups irrespective of duration or subsequent survival. There was, however, a close association between euglobulin lysis times (ELT) and survival. In the autograft recipients of livers subjected to 2 hr of ischemia that did not survive overnight the ELT remained significantly shortened. It is concluded that adenine nucleotide metabolism is important as an index of viability, but that concentrations of total and individual adenine nucleotides and the energy change all need to be computed. There does, however, appear to be an absolute relationship between survival and euglobulin lysis time that would be clinically useful in patients undergoing liver transplantation or hepatic vascular exclusion.
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