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Jain S, Curwood V, White SA, Furness PN, Nicholson ML. Sub-clinical acute rejection detected using protocol biopsies in patients with delayed graft function. Transpl Int 2001; 13 Suppl 1:S52-5. [PMID: 11111961 DOI: 10.1007/s001470050274] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Acute rejection in renal transplants is difficult to diagnose when patients have delayed graft function (DGF) in the early post-transplant period. In this study protocol, renal transplant biopsies were performed in an attempt to detect sub-clinical acute rejection episodes. Eighty-three patients were eligible for the study, of whom 33 had DGE All had protocol renal transplant biopsies performed under ultrasound control at 7 days post-transplant, and those with DGF had further biopsies weekly until the graft functioned. All histologically confirmed acute rejection episodes were treated. Sub-clinical acute rejection was detected in 6/33 (18%) patients with DGF compared to 2/50 (4%) in the other patients (P < 0.05). Borderline rejection was present in 4/33 (12%) and 4/50 (8%) patients, respectively. Because of the high detection rate of sub-clinical acute rejection and the low morbidity of renal transplant biopsies, their use is recommended in patients with DGF.
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Tiong HY, White SA, Khanna DS, Furness PN, Nicholson ML. An unusual presentation of follicular carcinoma of the thyroid. Thyroid 2001; 11:591-3. [PMID: 11442007 DOI: 10.1089/105072501750302903] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Lovering AL, Hyde EI, Searle PF, White SA. The structure of Escherichia coli nitroreductase complexed with nicotinic acid: three crystal forms at 1.7 A, 1.8 A and 2.4 A resolution. J Mol Biol 2001; 309:203-13. [PMID: 11491290 DOI: 10.1006/jmbi.2001.4653] [Citation(s) in RCA: 91] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Escherichia coli nitroreductase is a flavoprotein that reduces a variety of quinone and nitroaromatic substrates. Its ability to convert relatively non-toxic prodrugs such as CB1954 (5-[aziridin-1-yl]-2,4-dinitrobenzamide) into highly cytotoxic derivatives has led to interest in its potential for cancer gene therapy. We have determined the structure of the enzyme bound to a substrate analogue, nicotinic acid, from three crystal forms at resolutions of 1.7 A, 1.8 A and 2.4 A, representing ten non-crystallographically related monomers. The enzyme is dimeric, and has a large hydrophobic core; each half of the molecule consists of a five-stranded beta-sheet surrounded by alpha-helices. Helices F and F protrude from the core region of each monomer. There is an extensive dimer interface, and the 15 C-terminal residues extend around the opposing monomer, contributing the fifth beta-strand. The active sites lie on opposite sides of the molecule, in solvent-exposed clefts at the dimer interface. The FMN forms hydrogen bonds to one monomer and hydrophobic contacts to both; its si face is buried. The nicotinic acid stacks between the re face of the FMN and Phe124 in helix F, with only one hydrogen bond to the protein. If the nicotinamide ring of the coenzyme NAD(P)H were in the same position as that of the nicotinic acid ligand, its C4 atom would be optimally positioned for direct hydride transfer to flavin N5. Comparison of the structure with unliganded flavin reductase and NTR suggests reduced mobility of helices E and F upon ligand binding. Analysis of the structure explains the broad substrate specificity of the enzyme, and provides the basis for rational design of novel prodrugs and for site-directed mutagenesis for improved enzyme activity.
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White SA, Robertson GS, London NJ, Dennison AR. Human islet autotransplantation to prevent diabetes after pancreas resection. Dig Surg 2001; 17:439-50. [PMID: 11124546 DOI: 10.1159/000051938] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/10/2022]
Abstract
In severe cases of chronic pancreatitis pain relief can often only be achieved by pancreas resection, however this may render the patient diabetic. In an effort to prevent diabetes some patients may be suitable for a simultaneous islet autotransplant. The last report from the International Islet Transplant Registry has reported 222 cases. This review discusses the current progress in human islet autotransplantation.
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White SA, Davies JE, Pollard C, Swift SM, Clayton HA, Sutton CD, Weymss-Holden S, Musto PP, Berry DP, Dennison AR. Pancreas resection and islet autotransplantation for end-stage chronic pancreatitis. Ann Surg 2001; 233:423-31. [PMID: 11224632 PMCID: PMC1421260 DOI: 10.1097/00000658-200103000-00018] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
OBJECTIVE To assess the safety and efficacy of islet autotransplantation (IAT) combined with total pancreatectomy (TP) to prevent diabetes. SUMMARY BACKGROUND DATA There have been recent concerns regarding the safety of TP and IAT. This is thought to be related to the infusion of large volumes of unpurified pancreatic digest into the portal vein. Minimizing the volume of islet tissue by purifying the pancreatic digest has not been previously evaluated in terms of the postoperative rate of death and complications, pain relief, and insulin independence. METHOD During a 54-month period, 24 patients underwent pancreas resection with IAT. Islets were isolated using collagenase and a semiautomated method of pancreas digestion. Where possible, islets were purified on a density gradient and COBE processor. Islets were embolized into the portal vein, within the spleen and portal vein, or within the spleen alone. The total median volume of digest was 9.9 mL. RESULTS The median number of islets transplanted was 140,419 international islet equivalents per kilogram. The median increase in portal pressure was 8 mmHg. Early complications included duodenal ischemia, a wedge splenic infarct, partial portal vein thrombosis, and splenic vein thrombosis. Intraabdominal adhesions were the main source of long-term problems. Eight patients developed transient insulin independence. Three patients were insulin-independent as of this writing. Patients had significantly decreased insulin requirements and glycosylated hemoglobin levels compared with patients undergoing TP alone. Of the patients alive and well as of this writing, four had failed to gain relief of their abdominal pain and were still opiate-dependent. CONCLUSION Combined TP and IAT can be a safe surgical procedure. Unfortunately, almost all patients were still insulin-dependent, but they had decreased daily insulin requirements and glycosylated hemoglobin levels compared with patients undergoing TP alone. A prospective randomized study is therefore needed to assess the long-term benefit of TP and IAT on diabetic complications.
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Cotton NP, White SA, Peake SJ, McSweeney S, Jackson JB. The crystal structure of an asymmetric complex of the two nucleotide binding components of proton-translocating transhydrogenase. Structure 2001; 9:165-76. [PMID: 11250201 DOI: 10.1016/s0969-2126(01)00571-8] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
BACKGROUND Membrane-bound ion translocators have important functions in biology, but their mechanisms of action are often poorly understood. Transhydrogenase, found in animal mitochondria and bacteria, links the redox reaction between NAD(H) and NADP(H) to proton translocation across a membrane. Linkage is achieved through changes in protein conformation at the nucleotide binding sites. The redox reaction takes place between two protein components located on the membrane surface: dI, which binds NAD(H), and dIII, which binds NADP(H). A third component, dII, provides a proton channel through the membrane. Intact membrane-located transhydrogenase is probably a dimer (two copies each of dI, dII, and dIII). RESULTS We have solved the high-resolution crystal structure of a dI:dIII complex of transhydrogenase from Rhodospirillum rubrum-the first from a transhydrogenase of any species. It is a heterotrimer, having two polypeptides of dI and one of dIII. The dI polypeptides fold into a dimer. The loop on dIII, which binds the nicotinamide ring of NADP(H), is inserted into the NAD(H) binding cleft of one of the dI polypeptides. The cleft of the other dI is not occupied by a corresponding dIII component. CONCLUSIONS The redox step in the transhydrogenase reaction is readily visualized; the NC4 atoms of the nicotinamide rings of the bound nucleotides are brought together to facilitate direct hydride transfer with A-B stereochemistry. The asymmetry of the dI:dIII complex suggests that in the intact enzyme there is an alternation of conformation at the catalytic sites associated with changes in nucleotide binding during proton translocation.
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White SA, Pollard C, Davies JE, Sutton CD, Hales CN, Dennison AR. Temporal relationship of insulin, intact proinsulin and split proinsulin after islet autotransplantation. Transplant Proc 2001; 33:680. [PMID: 11267014 DOI: 10.1016/s0041-1345(00)02199-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Evans NJ, White SA, Bicknell GR, Furness PN, Nicholson ML. The expression of endothelin and inducible nitric oxide synthase in human renal allografts and their role in chronic renal allograft nephropathy. Transplant Proc 2001; 33:1181. [PMID: 11267247 DOI: 10.1016/s0041-1345(00)02375-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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Nicholson ML, Metcalfe MS, White SA, Waller JR, Doughman TM, Horsburgh T, Feehally J, Carr SJ, Veitch PS. Corrections to “A comparison of the results of renal transplantation from non-heat-beating, conventional cadaveric, and living donors. Kidney Int 58:2585–2591, 2000”. Kidney Int 2001. [DOI: 10.1046/j.1523-1755.2001.90033.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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135
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Metcalfe MS, White SA, Saunders RN, Murphy GJ, Horsburgh T, Knight AJ, Nicholson ML. Long-term results of renal transplantation using organs from non-heart-beating donors. Transplant Proc 2001; 33:826. [PMID: 11267083 DOI: 10.1016/s0041-1345(00)02332-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Abstract
BACKGROUND Islet transplantation has the potential to cure diabetes mellitus. Nevertheless despite successful reversal of diabetes in many small animal models, the clinical situation has been far more challenging. The aim of this review is to discuss why insulin-independence after islet allotransplantation has been so difficult to achieve. METHODS A literature review was undertaken using Medline from 1975 to July 2000. Results reported to the International Islet Transplant Registry (ITR) up to December 1998 were also analysed. RESULTS Up to December 1998, 405 islet allotransplants have been reported the ITR. Of those accurately documented between 1990 and 1998 (n = 267) only 12% have achieved insulin-independence (greater than 7 days). However with refined peri-transplant protocols insulin independence at 1 year can reach 20%. CONCLUSIONS There are many factors which can explain the failure of achieving insulin-independence after islet allotransplantation. These include the use of diabetogenic immunosuppressive agents to abrogate both islet allo-immunity and auto-immunity, the critical islet mass to achieve insulin-independence and the detrimental effects of transplanting islets in an ectopic site. However recent evidence most notably from the Edmonton group demonstrates that islet allotransplantation still has great potential to become an established treatment option for diabetic patients.
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Abstract
We have expressed and purified a protein fragment from Entamoeba histolytica. It catalyses transhydrogenation between analogues of NAD(H) and NADP(H). The characteristics of this reaction resemble those of the reaction catalysed by a complex of the NAD(H)- and NADP(H)-binding subunits of proton-translocating transhydrogenases from bacteria and mammals. It is concluded that the complete En. histolytica protein, which, along with similar proteins from other protozoan parasites, has an unusual subunit organisation, is also a proton-translocating transhydrogenase. The function of the transhydrogenase, thought to be located in organelles which do not have the enzymes of oxidative phosphorylation, is not clear.
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White SA, Nicholson ML. Islet cell transplantation and type 1 diabetes mellitus. Diabet Med 2001; 18 Suppl 1:6-9. [PMID: 11289191] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
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White SA. Peripheral intravenous therapy-related phlebitis rates in an adult population. JOURNAL OF INTRAVENOUS NURSING : THE OFFICIAL PUBLICATION OF THE INTRAVENOUS NURSES SOCIETY 2001; 24:19-24. [PMID: 11836840] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
Abstract
To determine the incidence of peripheral intravenous therapy-related phlebitis in an adult population, 305 peripheral i.v. catheter sites were observed from the time of admission of the patient (or initiation of the first peripheral i.v. catheter) to the time of the participant's discharge from the facility (or 48 hours after the removal of the final catheter). Parameters monitored included patient demographics, diagnosis, i.v. fluids and medications, type of peripheral catheter, dwell time, and dressing integrity. Results showed that of the 10 cases of phlebitis found in nine study subjects, all were associated with catheters indwelling less than 72 hours. In three cases, although the catheter site was clear at the time of catheter removal, postinfusion phlebitis developed within 24 hours. Catheter site locations, diagnoses, medications, and i.v. fluids in these cases were varied.
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Nicholson ML, Metcalfe MS, White SA, Waller JR, Doughman TM, Horsburgh T, Feehally J, Carr SJ, Veitch PS. A comparison of the results of renal transplantation from non-heart-beating, conventional cadaveric, and living donors. Kidney Int 2000; 58:2585-91. [PMID: 11115095 DOI: 10.1046/j.1523-1755.2000.00445.x] [Citation(s) in RCA: 168] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
BACKGROUND In an attempt to address the shortage of conventional kidney donors, a non-heart-beating donor (NHBD) organ retrieval program has been established. We compared the results of kidney transplants from NHBDs (N = 77) with those from heart-beating cadaveric (HBD; N = 224) and living donors (LD; N = 49), performed in the same eight-year period. METHODS Patients dying after failed attempts at resuscitation in the accident department or after intracerebral hemorrhage/anoxia were considered as potential NHBDs. After death, in situ kidney perfusion and cooling were achieved using an intra-aortic catheter inserted via a femoral artery cut down. Kidney retrieval and transplant operations were performed using standard techniques. RESULTS The median (range) warm ischemic time for NHBD kidneys was 25 minutes (5 to 53 min). The initial function rates for NHBD, HBD, and LD transplants were 6.5, 76.3, and 93%, respectively. Primary nonfunction occurred in 5 of 75 evaluable NHBD transplants (7%) compared with only 6 out of 224 (2.7%) HBD and 1 out of 49 (2%) LD transplants (P = NS). Eighty-four percent of NHBD kidney recipients required postoperative dialysis for a median of 19 days. The mean (SD) serum creatinine at 12 months was 179 (73) micromol/L in NHBD kidneys compared with 152 (57) micromol/L for HBD kidneys and 138 (44) micromol/L for LD kidneys. The actuarial five-year graft survival rates for NHBD, HBD, and LD transplants were 79, 75, and 78%, respectively. During the period under study, NHBD organs accounted for 22% of the total renal transplant program. CONCLUSIONS Despite being associated with poor initial graft function, the long-term allograft survival of NHBD kidneys does not differ significantly from the results of HBD and LD transplants.
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Tiong HY, White SA, Roop L, Furness PN, Nicholson ML. Paraganglioma-an unusual solitary nodule of the thyroid. EUROPEAN JOURNAL OF SURGICAL ONCOLOGY 2000; 26:720-1. [PMID: 11078623 DOI: 10.1053/ejso.2000.0990] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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White SA, Sutton CD, Robertson GS, Furness PN, Dennison AR. Incidental adult nesidioblastosis after distal pancreatectomy for endocrine microadenoma. Eur J Gastroenterol Hepatol 2000; 12:1147-9. [PMID: 11057462 DOI: 10.1097/00042737-200012100-00013] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/10/2022]
Abstract
Persistent hyperinsulinaemic hypoglycaemia (nesidioblastosis) presenting with hypoglycaemia is extremely rare in adults. The features are suggestive of an insulinoma with a vague presentation and delayed diagnosis. We describe a report of adult nesidioblastosis in association with a pancreatic endocrine microadenoma.
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Abstract
BACKGROUND The recent expansion of renal replacement therapy programmes has been associated with an increase in the number and complexity of patients requiring permanent vascular access. The introduction of strategies designed to maximize secondary access patency is, therefore, increasingly important as a means of prolonging patient survival on dialysis, reducing morbidity and reducing the escalating cost of such programmes. METHODS A review of the current literature on the planning of vascular access, access surveillance methods and treatment of the most common complications was performed. RESULTS Multidisciplinary vascular access planning, increased use of preoperative imaging and the preferential use of autogeneous vein are essential to obtain the best long-term results. While vascular access surveillance, in particular protocols involving direct measurement of access flow, enables the prospective detection and treatment of venous stenosis, the precise indications for treating venous stenosis remain unclear. Surgical revision remains the gold standard for the treatment of failing arteriovenous fistulas, but recent advances in interventional radiological techniques along with the suitability of arteriovenous fistulas for percutaneous intervention may offer an effective alternative. The effect of both these interventions on access patency requires comparison in a randomized trial. CONCLUSION The introduction of strategies to improve access patency rates will change vascular access surgical practice away from the construction of new fistulas towards an increase in outpatient percutaneous intervention and surgical revisional procedures. The role of surgical interventions requires clearer definition.
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White SA, Nicholson ML, Hering BJ. Can islet cell transplantation treat diabetes? BMJ (CLINICAL RESEARCH ED.) 2000; 321:651-2. [PMID: 10987752 PMCID: PMC1118541 DOI: 10.1136/bmj.321.7262.651] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Doyle E, Fowles SE, McDonnell DF, McCarthy R, White SA. Rapid determination of gemifloxacin in human plasma by high-performance liquid chromatography-tandem mass spectrometry. JOURNAL OF CHROMATOGRAPHY. B, BIOMEDICAL SCIENCES AND APPLICATIONS 2000; 746:191-8. [PMID: 11076071 DOI: 10.1016/s0378-4347(00)00333-9] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
A method was developed for the determination of gemifloxacin (I) in human plasma using high-performance liquid chromatography-tandem mass spectrometry. Prior to analysis, the protein in plasma samples was precipitated with acetonitrile containing [13C2H3] gemifloxacin (II) to act as an internal standard. The supernatant was injected onto a PLRP-S column without any further clean-up. The mass spectrometer was operated in positive ion mode, employing a heat assisted nebulisation. electrospray interface. Ions were detected in multiple reaction monitoring (MRM) mode. The assay requires 50 microl of plasma and is precise and accurate within the range 10-5,000 ng/ml. The average within-run and between-run coefficients of variation were <11% at 10 ng/ml and greater concentrations. The average accuracy of validation standards was generally within +/-7% of the nominal concentration. There was no evidence of instability of I in human plasma following three complete freeze-thaw cycles and samples can safely be stored for at least 6 months at -20 degrees C. The method proved very robust and was successfully applied to the analysis of clinical samples from patients dosed with gemifloxacin.
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Sutton CD, White SA, Berry DP, Dennison AR. Intrahepatic biliary cystadenoma causing luminal common bile duct obstruction. Dig Surg 2000; 17:297-9. [PMID: 10867471 DOI: 10.1159/000018857] [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: 01/12/2023]
Abstract
BACKGROUND Biliary cystadenomas are rare cystic tumours that arise in the liver or less frequently in the extrahepatic biliary system. They are commoner in middle-aged women, their most favoured site is the right hepatic lobe. METHODS Case report and review of the literature. RESULTS We present only the second case of an intrahepatic cystadenoma causing luminal obstruction of the common bile duct. Clinical presentation is often non-specific and can prove to be a diagnostic challenge. CONCLUSION Wide local excision of biliary cystadenomas is recommended, with regular radiological follow-up.
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Buckley PA, Baz Jackson J, Schneider T, White SA, Rice DW, Baker PJ. Protein-protein recognition, hydride transfer and proton pumping in the transhydrogenase complex. Structure 2000; 8:809-15. [PMID: 10997900 DOI: 10.1016/s0969-2126(00)00171-4] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
BACKGROUND Membrane-bound ion pumps are involved in metabolic regulation, osmoregulation, cell signalling, nerve transmission and energy transduction. How the ion electrochemical gradient interacts with the scalar chemistry and how the catalytic machinery is gated to ensure high coupling efficiency are fundamental to the mechanism of action of such pumps. Transhydrogenase is a conformationally coupled proton pump linking a proton gradient to the redox reaction between NAD(H) and NADP(H). The enzyme has three components; dI binds NAD(H), dII spans the membrane and dIII binds NADP(H). RESULTS The first crystal structure of a transhydrogenase dI component (from Rhodospirillum rubrum) has been determined at 2.0 A resolution. The monomer comprises two domains. Both are involved in dimer formation, and one has a Rossmann fold that binds NAD+ in a novel mode. The two domains can adopt different conformations. In the most closed conformation, the nicotinamide ring is expelled from the cleft between the two domains and is exposed on the outside of the protein. In this conformation it is possible to dock the structure of dI/NAD+ with that of a dIII/NADP+ complex to provide the first insights into the molecular basis of the hydride-transfer step. CONCLUSIONS Analysis of the model of the dI/dIII complex identifies residues potentially involved in dI/dIII interaction and shows how domain motion in dI results in a shift in position of the nicotinamide ring of NAD+. We propose that this movement is responsible for switching between the forbidden and allowed states for hydride transfer during proton pumping.
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White SA, LoBuglio AF, Arani RB, Pike MJ, Moore SE, Barlow DL, Conry RM. Induction of anti-tumor immunity by intrasplenic administration of a carcinoembryonic antigen DNA vaccine. J Gene Med 2000. [PMID: 10809147 DOI: 10.1002/(sici)1521-2254(200003/04)2:2<135::aid-jgm88>3.0.co;2-o] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
BACKGROUND We have previously reported that intramuscular, intradermal or epidermal gene gun administration of a plasmid encoding carcinoembryonic antigen (CEA) under transcriptional regulatory control of the cytomegalovirus (CMV) early promoter/enhancer elicits CEA-specific humoral and cellular immune responses in mice with resultant immunoprotection against challenge with syngeneic, CEA-expressing colon adenocarcinoma cells. METHODS In the present work, we examine the ability of this DNA vaccine construct (pCEA) to elicit CEA-specific immunity following intrasplenic administration. Groups of mice were immunized with pCEA by intrasplenic or intramuscular injection. Six weeks later, mice were evaluated for the presence of anti-CEA humoral responses and were challenged with syngeneic, CEA-expressing colon carcinoma cells. RESULTS Intrasplenic administration of pCEA produced a frequency of CEA-specific antibody responses comparable to that elicited by intramuscular pCEA inoculation. Both intrasplenic and intramuscular administration of pCEA generated IgG2a antibody responses to CEA, consistent with the induction of T helper-1-biased immune responses. In addition, partial immunoprotection against tumor challenge was observed after a single plasmid DNA dose by either route of administration. Subsequent studies revealed that antibody responses to intrasplenic DNA vaccination are dose and schedule dependent. CONCLUSION These findings support future investigations of DNA vaccination strategies that specifically promote the uptake of plasmid by splenocytes.
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Nicholson ML, Wheatley TJ, Doughman TM, White SA, Morgan JD, Veitch PS, Furness PN. A prospective randomized trial of three different sizes of core-cutting needle for renal transplant biopsy. Kidney Int 2000; 58:390-5. [PMID: 10886586 DOI: 10.1046/j.1523-1755.2000.00177.x] [Citation(s) in RCA: 121] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
BACKGROUND Needle-core biopsy remains one of the most important investigations in cases of renal allograft dysfunction. The size and quality of the biopsy material are likely to be important factors in achieving an accurate diagnosis. The aim of this study was to compare the success and complication rates of renal transplant biopsy procedures using three differently sized needles. METHODS One hundred renal allograft recipients undergoing transplant biopsy using an automated needle core method were randomized to a 14, 16, or 18 gauge (G) needle. The size of each biopsy core was measured, and the presence or absence of renal cortical and medullary tissue and the number of glomeruli were recorded. Assessments of the ease with which the procedure was performed, the diagnostic usefulness of the biopsy material, and the discomfort associated with the procedure were made using verbal response and linear analog scales. RESULTS Fourteen G biopsy cores (N = 33) were larger than both 16G (N = 33) and 18G (N = 34) cores and contained more gomeruli (mean number for 14G, 16G, and 18G = 15, 11 and 9, respectively). There were no differences in the ease of use of the three needle types, but scores for diagnostic usefulness were higher for 14G versus 18G and 16G versus 18G. The 14G needle was associated with significantly more pain than the two smaller needles when this was assessed using a linear analog score. Macroscopic hematuria occurred in eight patients, but there were no differences in complications rates between the three groups. CONCLUSIONS All three needle sizes are safe for use in renal allograft biopsy using a semiautomated biopsy gun. The larger needles provide more tissue and glomeruli and, thus, are more diagnostically useful. Use of a 14G needle may be associated with more pain, and the 16G needle appears to offer the best compromise between diagnostic usefulness and patient acceptability.
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Murphy GJ, White SA, Knight AJ, Doughman T, Nicholson ML. Long-term results of arteriovenous fistulas using transposed autologous basilic vein. Br J Surg 2000; 87:819-23. [PMID: 10928809 DOI: 10.1046/j.1365-2168.2000.01435.x] [Citation(s) in RCA: 75] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
BACKGROUND The transposed autologous basilic vein to brachial artery arteriovenous fistula provides vascular access in the absence of adequate superficial vein. The long-term patency and complication rates of this conduit are largely unreported. PATIENTS AND METHODS Seventy-four brachiobasilic fistulas were performed in 65 patients. This was a secondary or tertiary access procedure in 84 per cent of patients. RESULTS Of the 74 fistulas performed, 50 were successfully used for dialysis (68 per cent) and 24 (32 per cent) were never used, including 13 fistulas that failed without being used for dialysis. Of the 74 fistulas, 46 per cent failed (n = 34), 10 patients died with a functioning fistula (n = 10) and five were transplanted. The 30-day secondary patency was 73 per cent at 1 year, 53 per cent at 2 years and 43 per cent at 3 years rate was 96 per cent. Cumulative secondary patency was 73 per cent at 1 year, 53 per cent at 2 years and 43 per cent at 3 years. Nineteen (26 per cent) fistulas underwent a further 19 operative procedures. Fifty-one (69 per cent) fistulas developed complications. The most common complications were arm oedema (24 per cent), thrombosis (22 per cent) and bleeding (18 per cent). CONCLUSION In high-risk patients the autologous transposed brachiobasilic fistula has equivalent patency and lower complication rates than those reported for polytetrafluoroethylene interposition grafts.
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