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J Sutherland

Publications and source records attributed to J Sutherland.

At least 19 recordsLinked to original sources
PubMed2006

Validation of candidate bovine reference genes for use with real-time PCR.

Accurate quantification with real-time PCR requires the use of stable endogenous controls. Recently, there has been much debate concerning the stability of commonly used reference or housekeeping genes. To address this concern, a number of statistical approaches have been designed to analyse data and assist in determining the most appropriate reference genes for experimental comparisons. In this study, three programs, BestKeeper, Norm Finder, and geNorm were used to assess four candidate reference genes: 18S rRNA, glyceraldehyde-3-phosphate dehydrogenase (GAPDH), acidic ribosomal protein large (RPLP0) and beta-actin, for use in expression profiling of individuals from divergent cattle genotypes subject to parasitic challenge with the cattle tick Boophilus microplus. Results demonstrated beta-actin and GAPDH were the most suitable reference genes in blood and could be used either individually or combined as an index to normalise data. RPLP0 was identified as the least stable gene, while 18S rRNA was omitted as being too highly expressed. As the recommendations on the most suitable reference genes varied between the programs, it is recommended that more than one should be utilised, to ensure the most robust experimental tools are selected.

Actins↗
PubMed2006

Liposomal encapsulated doxorubicin (Caelyx) in the treatment of relapsed aggressive non-Hodgkin's lymphoma: a phase II study.

Aggressive non-Hodgkin's lymphoma (NHL), such as diffuse large B-cell lymphoma, can be cured in approximately 50% of cases, but those cases that recur and are not amenable to high-dose chemotherapy rely on palliative chemotherapy to improve symptoms and prolong life. Anthracyclines are associated with a high response rate in aggressive NHL but extended treatment results in cardiotoxicity. Liposomal encapsulated doxorubicin has been shown in other tumor types to allow for extended treatment with doxorubicin, but is associated with a low cardiac risk. The present study aimed to assess the response rate, survival and cardiac risk of patients with relapsed aggressive NHL treated with liposomal encapsulated doxorubicin. Eighteen patients with relapsed aggressive NHL were treated with liposomal encapsulated doxorubicin (40 - 50 mg/m2) for a planned six cycles. Some 83% of patients had diffuse large B-cell or mantle cell NHL. Four patients had a partial response (23%), whereas five patients had stable disease. None had a complete response. Eight patients progressed when receiving the liposomal encapsulated doxorubicin therapy. The median survival time was 34 weeks, and the median progression-free survival was 15.7 weeks. Overall survival was 50% at 6 months and 39% at 12 months. Progression-free survival was 33% at 6 months and was 28% at 12 months. The mean ejection fraction pre- and post-liposomal encapsulated doxorubicin treatment remained the same. Only one patient had a drop in ejection fraction to <50%. Liposomal encapsulated doxorubicin offers another choice to patients seeking palliation from their lymphoma recurrence with a response rate of 23% that was well tolerated and had a minimal cardiotoxic risk.

Aged↗
PubMed2005

In vitro function of platelet concentrates prepared after filtration of whole blood or buffy coat pools.

BACKGROUND/METHOD: Data on the quality of platelet concentrates (PC) produced by the buffy coat method and stored beyond 5 days in plasma are limited. We therefore evaluated the quality of PCs prepared by leucocyte depletion of whole blood (Terumo WBSP, n = 10) or a buffy coat pool (Pall Autostop, n = 10), and stored for 7 days in plasma by assessing platelet parameters and markers of platelet activation. RESULTS: In both types of PC, levels of glucose decreased during storage but were not totally depleted (> 11 mM on day 7). In contrast, lactate levels increased on storage and was consistently < 20 mM throughout, with pH maintained at > 6.8 in all units. Hypotonic shock response scores were > 47% in all units at day 7. On day 1, markers of platelet activation were significantly higher in WBSP PC, but by day 7 were similar for percentage CD63+ and CD62P + (40%) with levels of platelet microparticles and annexin V binding two-fold higher in WBSP. The expression of CD61 did not alter during storage and the percentage of platelets expressing CD42b was > 88% in all units on day 7. RANTES (Regulated on activation, normal, T-cell expressed and secreted) and TGFbeta released from platelets by day 7 was < 800 ng/ml and 90 ng/ml, respectively. C3a(desarg) increased throughout storage in both types of PC, but without a commensurate increase in the terminal complex SC5b-9 or activation of factor XII. CONCLUSION: Our data indicates that the in vitro characteristics of PCs prepared using these methods is maintained over storage for 7 days in plasma and is not associated with significant deterioration of platelet function. ONE SENTENCE SUMMARY: In vitro function of platelet concentrates prepared by either filtration of whole blood, or pooled buffy coats.

Analysis of Variance↗
PubMed2004

Treatment of MTBE by air stripping, carbon adsorption, and advanced oxidation: technical and economic comparison for five groundwaters.

An investigation was made of the treatability of methyl tert-butyl ether (MTBE) in five groundwaters with highly varied water quality characteristics. Air stripping, granular activated carbon (GAC) adsorption, and the O(3)/H(2)O(2) and UV/H(2)O(2) advanced oxidation processes were compared in a mobile water treatment pilot plant under a variety of process conditions. Air stripping was shown to have the lower unit treatment costs for higher flowrates (i.e., 3800L/min), although relatively tall towers were required for greater treatment requirements. At low flowrates (i.e., 38L/min), advanced oxidation provided the lowest treatment costs for four of five waters (but was ineffective for a high chemical oxygen demand water). Both the O(3)/H(2)O(2) and UV/H(2)O(2) processes were more efficient at pH 7 versus 9 due in part to increased scavenging at higher pH. GAC was examined using rapid small-scale column tests (RSSCT). GAC was effective at most conditions, although it was also the most costly alternative for most waters. The results of this study can help to provide specific guidance into process selection for treating MTBE in contaminated groundwaters.

Adsorption↗
PubMed2004

A simple spectrophotometric method for the quantification of residual haemoglobin in platelet concentrates.

BACKGROUND AND OBJECTIVES: High levels of residual haemoglobin (Hb 0.1 g/l) are known to decrease the efficiency of pathogen-inactivation systems. We evaluated three separate methods to quantify Hb in platelet concentrates (PC). MATERIALS AND METHODS: Nine PC prepared in platelet additive solution (PASIII) (median platelet yield of 283 x 10(9)/unit, range 46-353) were spiked to known Hb concentrations with whole blood and the samples were measured by using each of three methods: the 3,3',5,5'-tetramethylbenzidine (TMB) oxidation method (Sigma Diagnostics, 527-A); the Harboe spectrophotometric method; and the HemoCue plasma low-Hb photometer (PLHP). RESULTS: The TMB and Harboe methods showed linear results compared to expected Hb (r2 > or = 0.981, P < 0.001) over the range tested (0.09-0.28 g/l) when the samples were haemolysed. The TMB method underestimated by an average of 6%, at and around 0.1 g/l Hb, compared to a 4% overestimation by the Harboe method and a threefold overestimation by the PLHP. The Harboe intra-assay coefficient of variation was < or = 1.85% across all concentrations, which contrasted with 30% at and around 0.1 g/l for the TMB method. CONCLUSIONS: The Harboe spectrophotometric method is convenient, safe, accurate and reproducible, and outperforms the TMB and PLHP methods for quantification of residual Hb in PC.

Blood Preservation↗
PubMed2003

Expression of a plant-derived peptide harboring water-cleaning and antimicrobial activities.

Drinking water is currently a scarce world resource, the preparation of which requires complex treatments that include clarification of suspended particles and disinfection. Seed extracts of Moringa oleifera Lam., a tropical tree, have been proposed as an environment-friendly alternative, due to their traditional use for the clarification of drinking water. However, the precise nature of the active components of the extract and whether they may be produced in recombinant form are unknown. Here we show that recombinant or synthetic forms of a cationic seed polypeptide mediate efficient sedimentation of suspended mineral particles and bacteria. Unexpectedly, the polypeptide was also found to possesses a bactericidal activity capable of disinfecting heavily contaminated water. Furthermore, the polypeptide has been shown to efficiently kill several pathogenic bacteria, including antibiotic-resistant isolates of Staphylococcus, Streptococcus, and Legionella species. Thus, this polypeptide displays the unprecedented feature of combining water purification and disinfectant properties. Identification of an active principle derived from the seed extracts points to a range of potential for drinking water treatment or skin and mucosal disinfection in clinical settings.

Amino Acid Sequence↗
PubMed2003

The influence of platelet additive solutions on cytokine levels and complement activation in platelet concentrates during storage.

BACKGROUND AND OBJECTIVES: The accumulation of platelet-derived cytokines in platelet concentrates (PC) during storage may contribute towards non-haemolytic transfusion reactions (NHTR). We investigated the effect of platelet storage medium on platelet activation, complement activation and cytokine levels in leucocyte-reduced PC. MATERIALS AND METHODS: Hyperconcentrated platelets (3000-6000 x 109/l) were collected by apheresis and diluted in 100% plasma, 70% PASIII, or 70% or 80% PASIII supplemented with magnesium and potassium (PAS IIIM). RESULTS: Levels of transforming growth factor-beta (TGF-beta) and regulated on activation, normal, T-cell expressed, and secreted (RANTES) increased during storage, as did the expression of P-selectin (CD62P), and were highest in PC stored in PASIII. In PC stored in PASIIIM, however, levels of TGF-beta and RANTES were not significantly different from PC stored in plasma. Levels of CD62P expression, however, remained higher in PASIIIM PC than in those stored in plasma by day 5, but were lower than PC stored in PASIII. C3a des arg levels increased during storage in all media with the exception of PASIII and, on day 7, were higher in PC stored in plasma compared to PC stored in the other media. CONCLUSIONS: Our results indicate that replacing plasma in PC with unmodified PASIII for storage results in higher levels of platelet-derived cytokines in PC. Furthermore, it appears that the nature of the medium used for storage of PC has a significant impact on platelet activation and cytokine levels of the PC. These implications should be taken into account when considering replacement of plasma with PAS.

Blood Platelets↗
PubMed2002

Molecular mechanisms of nickel carcinogenesis.

Humans are exposed to carcinogenic nickel (Ni) compounds both occupationally and environmentally. In this paper, molecular mechanisms of nickel carcinogenesis are considered from the point-of-view of the uptake of nickel sulfide particles in cells, their dissolution and their effects on heterochromatin. Molecular mechanisms by which nickel induces gene silencing, DNA hypermethylation and inhibition of histone acetylation, will be discussed.

Acetylation↗
PubMed2001

Mutation analysis of the tyrosinase gene in oculocutaneous albinism.

Type I oculocutaneous albinism (OCA) is an autosomal recessive disorder caused by the reduction or the absence of tyrosinase (TYR) activity in melanocytes of the skin, hair and eyes. Here we report an analysis of 45 patients with OCA. We found five novel mutations in the tyrosinase gene involved in the pathogenesis of oculocutaneous albinism type IA or type IB (OCA-1A/B) in five unrelated patients. Three mutations are missense mutations (G109R, P205T and H256Y) and two are nucleotide deletions (336-337delCA and 678-680delAGG). One patient is homozygous for the previously known V275F mutation but has an extremely mild OCA phenotype and has no eye features typical of OCA. In several patients we discovered only one or even no mutation in the coding sequence of the TYR gene. Thus, this disease may also result from mutations in non coding regions of the gene or in another gene involved in the biosynthesis of melanin. Hum Mutat 17:352, 2001.

Albinism↗
PubMed2001

The effect of leucocyte depletion on the quality of fresh-frozen plasma.

The aim of this study was to evaluate the quality of leucodepleted (LD) fresh-frozen plasma (FFP) produced using one of five whole blood filters (Baxter RS2000 & RZ2000, NPBI T2926, Macopharma LST1 and Terumo WBSP) or two plasma filters (Pall LPS1 and Baxter FGR7014). Whole blood or plasma was filtered within 8 h of collection at an ambient temperature. Samples were taken pre- and post filtration for analysis of coagulation factors and complement activation (n = 7--12 for each type of filter). All filtered units (209--286 ml) contained < 5 x 10(6) residual leucocytes and < 30 x 10(9)/l platelets. Statistically significant losses of factors V, VIII, IX, XI and XII and increases in markers of coagulation activation were observed (0--21%), which were dependent on filter type. None of the filters had a significant effect on von Willebrand factor (VWF) multimeric distribution or the activity of VWF and factors II, VII or X. The effect on levels of C3a appeared to be related to the filter surface charge: positively charged filters resulted in C3a generation, whereas negatively charged resulted in C3a removal. None of the observed changes are likely to be clinically significant unless subsequent processing of plasma (such as pathogen inactivation) results in further losses of coagulation factors.

Blood Coagulation Factors↗
PubMed2001

Residual subset population analysis in WBC-reduced blood components using real-time PCR quantitation of specific mRNA.

BACKGROUND: Implementation of WBC reduction of the blood supply increases the importance of measurement of residual WBC subtypes responsible for immunologic and infectious complications of transfusion. STUDY DESIGN AND METHODS: Real-time RT-PCR assays were developed to detect mRNA encoding lineage-specific WBC markers. Primers and fluorescent probes were designed for CD45 (pan-WBC), CD3 (T-lymphocyte), CD19 (B-lymphocyte), CD14 (monocyte), and CD66 (granulocyte), and the specificity was assessed by comparison with flow cytometric analysis of enriched cell populations. WBC subsets were examined in WBC-reduced whole blood prepared with filters (WBF2, Pall; and RZ2000, Baxter) and in platelet concentrates prepared with other filters (Autostop, Pall; and PLX-5, Baxter) and apheresis (COBE Spectra LRS, Gambro). RESULTS: All real-time RT-PCR assays were linear over >5 log concentration range, allowing pre-WBC-reduction and post-WBC-reduction comparisons. Sensitivity limits ranged from 10 cells per mL (CD45) to 200 cells per mL (CD19). Assay specificity was confirmed by the close correlation of real-time RT-PCR and immunophenotyping results by flow cytometry. For all subsets, >3.8 log and >3.1 log reduction was obtained during WBC reduction of whole blood and platelets, respectively. CONCLUSION: Real-time RT-PCR assays are suitable for analysis of subset removal during WBC reduction. There was no significant difference between the two whole-blood filters or between platelet filtration and apheresis in the removal of any WBC subset.

Antigens, CD↗
PubMed2001

Anaesthesia for amiodarone-induced thyrotoxicosis: a case review.

Amiodarone-induced thyrotoxicosis is a life-threatening problem that is very effectively managed by total thyroidectomy, although often many of these patients are considered "too unfit" for anaesthesia. The aim of this study was to review the safety of anaesthesia for total thyroidectomy in the acute management of amiodarone-induced thyrotoxicosis. Information was obtained retrospectively from a prospective endocrine surgical database and from hospital records. Data, including outcomes and morbidity, are presented from 12 patients who underwent anaesthesia for total thyroidectomy as an urgent procedure for amiodarone-induced thyrotoxicosis. Despite the fact that these patients had uncontrolled thyrotoxicosis and marked cardiac failure at the time of anaesthesia, no anaesthetic or surgical mortality was seen. We conclude that a challenging patient with amiodarone-induced thyrotoxicosis that has not responded to conservative measures may be considered for total thyroidectomy early in their management. Total thyroidectomy can be performed under general or local anaesthesia with apparent relative safety.

Adult↗
PubMed2001

Power to the PDA.

Explore the source record for details and available documents.

Computer Communication Networks↗
PubMed2001

Clustered DNA damages induced by high and low LET radiation, including heavy ions.

Clustered DNA damages--here defined as two or more lesions (strand breaks, oxidized purines, oxidized pyrimidines or abasic sites) within a few helical turns--have been postulated as difficult to repair accurately, and thus highly significant biological lesions. Further, attempted repair of clusters may produce double strand breaks (DSBs). However, until recently, there was no way to measure ionizing radiation-induced clustered damages, except DSB. We recently described an approach for measuring classes of clustered damages (oxidized purine clusters, oxidized pyrimidine clusters, abasic clusters, along with DSB). We showed that ionizing radiation (gamma rays and Fe ions, 1 GeV/amu) does induce such clusters in genomic DNA in solution and in human cells. These studies also showed that each damage cluster results from one radiation hit (and its track), thus indicating that they can be induced by very low doses of radiation, i.e. two independent hits are not required for cluster induction. Further, among all complex damages, double strand breaks comprise--at most-- ~20%, with the other clustered damages being at least 80%.

Cells, Cultured↗
PubMed2000

Discriminative stimulus effects of two doses of fentanyl in rats: pharmacological selectivity and effect of training dose on agonist and antagonist effects of mu opioids.

RATIONALE: Discriminative stimulus effects of mu opioids vary systematically as a function of training dose. Differences among training doses may arise from multiple mechanisms. OBJECTIVES: In vivo apparent pA(2) analyses were used to examine the contributions of opioid mechanisms to stimulus control by low and high training doses of the mu opioid fentanyl. METHODS: Saline and one of two doses of fentanyl, administered s.c., were established as discriminative stimuli in two groups of rats (low training dose group: 0.01 mg/kg; high training dose group: 0.04 mg/kg). Generalization tests and in vivo apparent pA(2) analyses were used to evaluate receptor mechanisms of stimulus control. RESULTS: Fentanyl, etonitazene, methadone, and morphine evoked full fentanyl generalization in both groups but were more potent in the low-dose group. Spiradoline and d-amphetamine did not evoke generalization in either group. Naltrexone antagonized stimulus and rate-altering effects of fentanyl in both groups, with apparent pA(2) values of 7. 6 in the low-dose group and 7.5 in the high-dose group. Nalbuphine and nalorphine evoked full generalization in the low-dose group but less than 40% generalization in the high-dose group. In the high-dose group, nalbuphine and nalorphine antagonized the stimulus and rate-altering effects of fentanyl with apparent pA(2) values of 5.3 and 6.1, respectively, demonstrating lower efficacy mu actions. CONCLUSIONS: Changes in fentanyl training dose preserved the mu opioid selectivity of stimulus control but altered the intensity of the transduced mu opioid stimulus required for generalization. These differences in intensity of the fentanyl stimulus determined whether low efficacy mu opioids would evoke or antagonize fentanyl generalization.

Analgesics, Opioid↗
PubMed2000

Thyroid surgery and anaesthesia following head and neck irradiation for childhood malignancy.

BACKGROUND: Increasing numbers of adolescents and young adults are undergoing thyroid surgery because of the risk of malignancy following previous irradiation for childhood malignancy. Irradiation to the head and/or neck regions may induce changes in the soft tissues and larynx that are far from normal with respect to both size and mobility. The aim of the present study was to evaluate the possible impact of such changes on both surgical and anaesthetic technique during thyroidectomy. METHODS: This was a retrospective ease study. Thirty consecutive patients undergoing total thyroidectomy following previous irradiation for childhood malignancy formed the study group. RESULTS: There were no permanent surgical or anaesthetic complications in the group. In particular there were no cases of either permanent recurrent laryngeal nerve palsy or permanent hypoparathyroidism. Twenty-eight patients had an uneventful intubation and two were unable to be intubated directly, one requiring fibre-optic bronchoscopic intubation and the other having surgery performed with a laryngeal mask following failed bronchoscopy. Both of these patients had received high-dose direct irradiation to the larynx for solid tumours. CONCLUSIONS: Despite potential difficulties associated with the heavily irradiated larynx, thyroid surgery and anaesthesia can be performed safely with minimal complications in experienced hands.

Adolescent↗
PubMed2000

Molecular characterisation of congenital glaucoma in a consanguineous Canadian community: a step towards preventing glaucoma related blindness.

Glaucoma is a leading cause of irreversible blindness in Canada. Congenital glaucoma usually manifests during the first years of life and is characterised by severe visual loss and autosomal recessive inheritance. Two disease loci, on chromosomes 1p36 and 2p21, have been associated with various forms of congenital glaucoma. A branch of a large six generation family from a consanguineous Amish community in south western Ontario was affected with congenital glaucoma and was studied by linkage and mutational analysis to identify the glaucoma related genetic defects. Linkage analysis using the MLINK component of the LINKAGE package (v 5.1) showed evidence of linkage to the 2p21 region (Zmax=3.34, theta=0, D2S1348 and D2S1346). Mutational analysis of the primary candidate gene, CYP1B1, was done by direct cycle sequencing, dideoxy fingerprinting analysis, and fragment analysis. Two different disease causing mutations in exon 3, 1410del13 and 1505G-->A, both segregated with the disease phenotype. The two different combinations of these alleles appeared to result in a variable expressivity of the phenotype. The compound heterozygote appeared to have a milder phenotype when compared to the homozygotes for the 13 bp deletion. The congenital glaucoma phenotype for this large inbred Amish family is the result of mutations in CYP1B1 (2p21). The molecular information derived from this study will be used to help identify carriers of the CYP1B1 mutation in this community and optimise the management of those at risk of developing glaucoma.

Adolescent↗