bluuebunny/crossref_metadata_2025 huggingface dataset:
Contribution of age, body size, and CYP2C9 genotype to anticoagulant response to warfarin
Authors: Kamali Farhad , Khan Tayyaba Irfan , King Barry P. , Frearson Richard , Kesteven Patrick , Wood Peter , Daly Ann K. , Wynne Hilary
Published: March 2004

Objective

Our objective was to assess the contribution of CYP2C9 genotype, age, body size, and vitamin K and lipid status to warfarin dose requirements.

Methods

Patients with stable warfarin dose requirements and an international normalized ratio (INR) of the prothrombin time within the target range of 2.0 to 3.0 were recruited to the study. On arrival at the clinic in the morning, after an overnight fast, a blood sample was taken from each patient for CYP2C9 genotyping and for determination of venous INR and plasma vitamin K, R‐ and S‐warfarin, and triglyceride concentrations.

Results

A total of 121 patients were recruited to the study. CYP2C9 genotyping showed that 74 patients were homozygous wild‐type (*1/*1), 30 were heterozygous *1/*2, and 15 were heterozygous *1/*3 genotype. One patient was found to have the genotype *2/*3, and another was found to have the genotype *3/*3. The mean warfarin daily dose requirement in milligrams fell from 4.06 ± 1.72 mg in homozygous wild‐type patients to 3.63 ± 1.78 mg for *1/*2‐positive patients and 2.70 ± 1.36 mg for *1/*3‐positive patients. The multiple linear regression model for warfarin dose indicated significant contributions from age (r = 0.41, P < .001), genotype (r = 0.24, P < .005), and age and genotype together (r = 0.45, P < .005). Although there were significant linear correlations between warfarin dose and body surface area (r = 0.21, P = .02), body weight (r = 0.25, P = .005), and plasma vitamin K concentration (r = 0.18, P < .05), none of these variables made a significant contribution to the regression model for warfarin dose. CYP2C9 genotype had a significant effect on S‐warfarin clearance (r = 0.34, P < .0001) but none on R‐warfarin clearance.

Conclusion

This study showed that age and CYP2C9 polymorphism affect warfarin dose requirements in patients receiving long‐term therapy and having stable control of anticoagulation. It is anticipated that using dosing regimens modified to take into account the contribution of age and CYP2C9 genotype has the potential to improve the safety of warfarin therapy.

Clinical Pharmacology & Therapeutics (2004) 75, 204–212; doi: 10.1016/j.clpt.2003.10.001
CYP2D6genotype and induction of intestinal drug transporters by rifampin predict presystemic clearance of carvedilol in healthy subjects
Authors: Giessmann Thomas , Modess Christiane , Hecker Ute , Zschiesche Michael , Dazert Peter , Kunert‐Keil Christiane , Warzok Rolf , Engel Georg , Weitschies Werner , Cascorbi Ingolf , Kroemer Heyo K. , Siegmund Werner
Published: March 2004

Background

Clinical trials have indicated that the combined β‐ and α‐adrenergic receptor blocker carvedilol improves the survival rate in patients with advanced chronic heart failure. The objective of our study was the identification and quantification of factors that modulate steady‐state serum concentrations of carvedilol and its enantiomers and that may influence therapeutic efficacy and safety.

Methods

The influence of genetic variants of cytochrome P450 (CYP) 2D6 and CYP2C9 and of transporter proteins (P‐glycoprotein, multidrug resistance protein 2 [MRP2]) on the disposition of carvedilol and its enantiomers after intravenous (5 mg) and long‐term oral administration (25 mg for 7 days) was assessed in 12 healthy subjects. The intestinal expression of P‐glycoprotein and MRP2 was analyzed by quantitative real‐time polymerase chain reaction and immunohistochemical techniques.

Results

The area under the serum concentration–time curve (AUC) values of carvedilol were significantly (P< .05) increased in 6 subjects with CYP2D6 deficiency, with effects being more pronounced forR(+)‐carvedilol (230 ± 72.6 ng · h/mL versus 93.9 ± 64.6 ng · h/mL in extensive metabolizers) than forS(−)‐carvedilol (62.9 ± 21.1 ng · h/mL versus 32.7 ± 14.5 ng · h/mL). The AUC and fecal excretion of intravenous carvedilol were correlated with the intestinal expression ofMDR1messenger ribonucleic acid (mRNA) (r= −0.67,P= .001;r= 0.83,P= .002) andMRP2mRNA (r= −0.74,P< .001;r= 0.70,P= .025). Furthermore, we measured the disposition of long‐term oral carvedilol after comedication of the pregnane X receptor ligand rifampin (INN, rifampicin) (600 mg, 9 days), which up‐regulates both P‐glycoprotein and MRP2 but not CYP2D6. Rifampin decreased the AUC of carvedilol to an extent independent of the CYP2D6 genotype (poor metabolizers, 341 ± 147 ng · h/mL versus 126 ± 41.7 ng · h/mL; extensive metabolizers, 173 ± 102 ng · h/mL versus 74 ± 41.4 ng · h/mL; bothP< .05). The AUC was significantly correlated with intestinal expression ofMDR1mRNA (r= −0.671,P= .001) andMRP2mRNA (r= −0.595,P< .006).

Conclusions

Variable plasma concentrations of carvedilol during long‐term administration are predicted by CYP2D6 genotype and intestinal expression of P‐glycoprotein and MRP2.

Clinical Pharmacology & Therapeutics(2004)75, 213–222; doi:10.1016/j.clpt.2003.10.004
Activities of Cytochrome P450 1A2, N‐acetyltransferase 2, Xanthine oxidase, and Cytochrome P450 2D6 are Unaltered in Children with Cystic Fibrosis
Authors: Kennedy Mary Jayne , Scripture Charity D. , Kashuba Angela D. M. , Scott Christy S. , Gaedigk Andrea , Kearns Gregory L.
Published: March 2004

The activities of hepatic cytochrome P450 (CYP) 1A2, N‐acetyltransferase 2 (NAT‐2), xanthine oxidase (XO), and CYP2D6 were evaluated in 12 young children (aged 3–8 years) with mild cystic fibrosis (CF) and 12 age‐matched healthy control subjects by use of standard caffeine and dextromethorphan phenotyping methods. Subjects were given 4 oz of Coca‐Cola (approximately 35 mg caffeine) (The Coca‐Cola Company, Atlanta, Ga) and a single 0.5‐mg/kg dose of dextromethorphan. Urine was collected for 8 hours after biomarker administration, and enzyme activity was assessed by use of previously validated caffeine and dextromethorphan molar ratios. CYP2D6 genotyping was also performed in 10 of 12 subjects with CF and 11 of 12 control subjects. There were no significant differences in the urinary molar ratios for any of the enzyme systems evaluated. These data suggest that CF does not alter the activities of CYP1A2, NAT‐2, XO, and CYP2D6. Altered biotransformation of drugs in this patient population is likely enzyme‐ and isoform‐specific and thus is apparent for only selected compounds that are substrates for enzymes other than CYP1A2, NAT‐2, XO, and CYP2D6.

Clinical Pharmacology & Therapeutics (2004) 75, 163–171; doi: 10.1016/j.clpt.2003.10.005
Systemic Exposure to Morphine and the Risk of Acute Chest Syndrome in Sickle Cell Disease
Authors: Kopecky Ernest A. , Jacobson Sheila , Joshi Prashant , Koren Gideon
Published: March 2004

Background

The etiology of acute chest syndrome, the most severe complication of the sickle cell crisis, is unknown.

Objective

Our objective was to assess exposure to morphine as an etiologic factor for acute chest syndrome in sickle cell disease.

Methods

A post hoc analysis of a randomized controlled trial comparing oral with continuous infusion of morphine was performed. Children (aged 5–17 years) with sickle cell crisis were randomized to receive oral sustained‐release morphine, 1.9 mg · kg−1 · 12 h−1, or a continuous intravenous infusion of morphine at 0.04 mg · kg−1 · h−1 by use of a double‐blind, placebo‐controlled design. In a subgroup of 15 patients, the pharmacokinetics of morphine and its active metabolite morphine‐6‐glucuronide were also studied.

Results

At baseline, demographic and physiologic characteristics were similar between groups. There were no differences in the number of previous rescue doses per day, painful sites per episode, physician contacts per year, and hospitalizations per year between treatment arms. There was a 2‐fold higher morphine area under the concentration‐time curve at steady state (AUCss) and a 3‐fold higher morphine‐6‐glucuronide AUCss with oral morphine than with a continuous intravenous infusion of morphine (P < .001 and P < .006, respectively). New onset of acute chest syndrome was 3‐fold more prevalent in the oral group (57%) versus the continuous intravenous infusion group (17%) (P < .001).

Conclusions

The risk of acute chest syndrome is significantly associated with high systemic exposure to morphine and its active metabolite morphine‐6‐glucuronide after oral administration of slow‐release morphine. Morphine may facilitate respiratory deterioration by eliciting a decrease in oxygen saturation, by inducing histamine release, or through an as‐yet‐unidentified mechanism. The safe systemic exposure to morphine in terms of area under the concentration‐time curve should be further studied in children with sickle cell disease.

Clinical Pharmacology & Therapeutics (2004) 75, 140–146; doi: 10.1016/j.clpt.2003.10.007
Pain management in cats—past, present and future. Part 1. The cat is unique
Authors: Taylor P.M. , Robertson S.A.
Published: March 2004

Cats are popular pets but until recently their perioperative and traumatic pain was seriously underestimated and under treated. There are several causes of this under treatment. First, it may be difficult to detect pain in cats, because they do not demonstrate overt pain-associated behaviour. Secondly, there are relatively few analgesic drugs with market authorisation for cats. Thirdly, cats have an unfortunate reputation for toxicity from analgesic drugs, particularly opioid-induced mania and classical non steroidal anti inflammatory drug toxicity. Fourthly, cats are deficient in some metabolic pathways used to metabolise analgesic drugs in other species; this may lead to genuine toxicity or to lack of effect. Recently, understanding of feline behaviour and physiology has improved, leading to better clinical management of this enigmatic species. Behavioural methods are proving to be the best means of assessing pain, and knowledge of unique feline physiology has enabled rational treatment protocols to be developed specifically for cats.
Diagnosis of feline haemoplasma infection in Australian cats using a real-time PCR assay
Authors: Tasker S. , Braddock J.A. , Baral R. , Helps C.R. , Day M.J. , Gruffydd-Jones T.J. , Malik R.
Published: March 2004

A total of 147 cats from the Sydney area of Australia that had blood samples submitted to veterinary laboratories were tested using a real-time polymerase chain reaction (PCR) assay able to detect and distinguish the two feline haemoplasma species. This sample number included two cats diagnosed with feline haemoplasma infection by routine blood smear examination. Statistical analysis was performed to evaluate associations between haemoplasma infection, age, sex, breed, haematocrit (HCT) values and anaemia status. One hundred and six cats (72.1%) were negative. Thirty-four cats (23.1%) were positive for ‘ Candidatus M. haemominutum’, six cats (4.1%) were positive for M. haemofelis and one cat (0.7%) was positive for both species. Older, male, non-pedigree cats, with lower HCT values were more likely to be infected with ‘ Candidatus M. haemominutum’. Significant inverse correlation was found between the amount of M. haemofelis DNA present in the blood and the HCT value. This report documents the existence of, and prevalence of, both haemoplasma species in a sample of cats in Australia and is the first to use quantitative real-time PCR in a prevalence study for haemoplasma infection.
Repair of Distal Biceps Tendon Ruptures Using a Suture Anchor and an Anterior Approach
Authors: BALABAUD L. , RUIZ C. , NONNENMACHER J. , SEYNAEVE P. , KEHR P. , RAPP E.
Published: March 2004

In a prospective study, eight consecutive patients with nine ruptures of the distal biceps tendon underwent repair through a single incision. All patients were satisfied with their clinical results and had full ranges of elbow and forearm motion. There were no radial nerve injuries and no radio-ulnar synostoses. Isokinetic testing, after correction for dominance, demonstrated a 6% strength deficit, but 7% higher endurance in the repaired extremity for the flexion-concentric test, and no strength deficit and 13% higher endurance for supination. The improved endurance is probably explained by initial reduced effort due to apprehension which minimized subsequent fatigue.
Assessment of mRNA Levels for Matrix Molecules and TGF-β1 in Rabbit Flexor and Peroneus Tendons Reveals Regional Differences in Steady-State Expression
Authors: BERGLUND M. , WIIG M. , TORSTENSSON M. , RENO C. , HART D. A.
Published: March 2004

This study analysed the differences on a molecular level between two segments of the deep flexor tendon, and compared the intrasynovial flexor tendon with the tendon sheath and the extrasynovial peroneus tendon in a rabbit model. The TRIspin method of RNA extraction was combined with the reverse transcription polymerase chain reaction to assess mRNA levels in the tissue segments. Significant differences were detected for all genes studied. mRNA levels for aggrecan, biglycan and collagen III were significantly higher in the fibrocartilaginous proximal segment of the flexor tendon. Collagen I was higher in the flexor tendon than the sheath and the peroneus tendon, and TGF-β1 was significantly lower in the peroneus tendon. This study demonstrates differences at the mRNA level between different segments of tendon, indicating that the tendon tissue may be adapted to its environment.
Tubular Repair of the Median or Ulnar Nerve in the Human Forearm: A 5-Year Follow-Up
Authors: LUNDBORG G. , ROSÉN B. , DAHLIN L. , HOLMBERG J. , ROSÉN I.
Published: March 2004

The long-term outcome from silicone tube nerve repair was compared with the outcome from routine microsurgical repair in a clinical randomized prospective study, comprising 30 patients with median or ulnar nerve injuries in the distal forearm. Postoperatively, the patients underwent neurophysiological and clinical assessments of sensory and motor function regularly over a 5-year period. After 5 years there was no significant difference in outcome between the two techniques except that cold intolerance was significantly less severe with the tubular technique. In the total group there was ongoing improvement of functional sensibility throughout the 5 years after repair. It is concluded that tubular repair of the median and ulnar nerves is at least as good as routine microsurgical repair, and results in less cold intolerance.
A Comparison of Two Indices for Ulnar Translation and Carpal Height in the Rheumatoid Wrist
Authors: BORISCH N. , LERCH K. , GRIFKA J. , HAUSSMANN P.
Published: March 2004

The indices for ulnar translation described by Chamay et al. (1983 , Annales de Chirurgie de la Main, Vol. 2, pp. 5–17), and Bouman et al. (1994 , Journal of Hand Surgery Vol. 19B, pp. 325–329), and for carpal height described by Youm et al. (1978 , Journal of Bone and Joint Surgery, Vol. 40A, pp. 423–431) and Bouman et al. (1994) were compared in pre- and postoperative wrist X-rays of 91 patients with rheumatoid arthritis undergoing radiolunate arthrodesis. Both indices described by Bouman had a higher applicability and sensitivity than the Chamay and Youm indices and are recommended for use with the rheumatoid wrist. However false-negative values may result when the Bouman index for ulnar translation is used to follow up radiolunate arthrodesis.
Minimally Invasive Fixation versus Conservative Treatment of Undisplaced Scaphoid Fractures: A Cost-Effectiveness Study
Authors: PAPALOIZOS M. Y. , FUSETTI C. , CHRISTEN T. , NAGY L. , WASSERFALLEN J. B.
Published: March 2004

This study compares the direct and indirect costs of conservative and minimally invasive treatment for undisplaced scaphoid fractures. Costs data concerning groups of non-operated and operated patients were analysed. Direct costs were higher in operated patients. Although highly variable, indirect costs were significantly smaller in operated patients and the total costs were higher in nonoperated patients. In conclusion, operative treatment of scaphoid fractures is initially more expensive than conservative treatment but markedly decreases the work compensation costs.
The Towel Test: A Useful Technique for the Clinical and Electromyographic Evaluation of Obstetric Brachial Plexus Palsy
Authors: BERTELLI J. A. , GHIZONI M. F.
Published: March 2004

The towel test consists of covering an infant’s face with a towel and seeing if he/she can remove it with either arm. In this study it has been used to aid the clinical and electromyographic assessment of 21 infants with obstetric brachial plexus palsy. At 2 to 3 months, none of the 21 infants succeeded in removing the towel, either with their normal or affected arm. At 6 months, all the infants succeeded in removing the towel with their normal arm, but 11 could not with their affected arm, and the same was observed at a further assessment at 9 months. The towel test is a reliable technique for evaluating children with obstetric brachial plexus injuries.
Acquired Localized Subcutaneous Cavernous Vascular Malformations of the Hand
Authors: AL-QATTAN M. M.
Published: March 2004

A series of 15 patients with acquired localized subcutaneous cavernous (venous) vascular malformations of the hand is reported. There were nine women and six men. The malformation was first noted at a mean age of 24 years (range, 16–40 years). Six patients had solitary lesions and nine had multiple lesions. A painful mass was the most common presenting symptom. Calcification within the malformation was noted radiologically in one-third of the patients. Patients were managed with simple excision of the symptomatic lesions with no recurrence.
The Indications for Toe Transfer after “Minor” Finger Injuries
Authors: PIÑAL F DEL
Published: March 2004

Toe-to-hand transfer is widely considered to be unjustified for “minor” finger injuries. In this invited personal view article the indications for toe-to-hand transfer for finger amputation and neurocutaneous and major pulp defects are discussed, and a classification of multidigital injury that has both prognostic and decision-making value is presented. In the author's opinion a toe transfer should always be considered as an option when reconstructing “minor” finger injuries, as it can reproduce significant long-term benefit to the hand and the patient's sense of well being. The procedure should be carried out in the acute period, not only because it is technically easier and better for hand function, but above all because the surgeon can save structures that will be lost if the transfer is delayed.
TNF‐α and IL‐4 regulate expression of fractalkine (CX3CL1) as a membrane‐anchored proadhesive protein and soluble chemotactic peptide on human fibroblasts
Authors: Yoshikawa Mamoru , Nakajima Toshiharu , Matsumoto Kenji , Okada Naoko , Tsukidate Toshiharu , Iida Makoto , Otori Nobuyoshi , Haruna Shin-ichi , Moriyama Hiroshi , Imai Toshio , Saito Hirohisa
Published: March 2004

The CX3C chemokine, fractalkine (FKN, CX3CL1), has multiple functions and exists as two distinct forms, a membrane‐anchored protein and a soluble chemotactic peptide that cleaves from the cell surface FKN. In this study, we first demonstrated the expression of FKN in tumor necrosis factor (TNF)‐α‐ and interleukin (IL)‐4‐stimulated human fibroblasts. The induction of FKN was observed for both forms. We also demonstrated monocyte chemotactic activity in the culture supernatant from the fibroblasts stimulated with these cytokines. These results suggest that TNF‐α‐ and IL‐4‐stimulated fibroblasts may play an important role in accumulation of monocytes at inflammatory sites.
Dynactins p25 and p27 are predicted to adopt the LβH fold
Authors: Parisi Gustavo , Fornasari Marı́a Silvina , Echave Julián
Published: March 2004

Dynactin is a multimeric protein essential for the minus‐end‐directed transport driven by microtubule‐based motor dynein. The pointed‐end subcomplex in dynactin contains p62, p27, p25, and Arp11 subunits, and is thought to participate in interactions with membranous cargoes. We used sequence and structure prediction analysis to study dynactins p25 and p27. Here we present evidence that strongly supports that dynactins p27 and p25 contain the isoleucine‐patch motif and adopt the left‐handed parallel β‐helix fold. The structural models we obtained could contribute to the understanding of the complex interactions that dynactins are able to establish with cargo particles, microtubules or other dynactin subunits.
Characterization of the human STAT5A and STAT5B promoters: evidence of a positive and negative mechanism of transcriptional regulation
Authors: Crispi Stefania , Sanzari Emma , Monfregola Jlenia , De Felice Nicola , Fimiani Giorgia , Ambrosio Raffaele , D'Urso Michele , Ursini Matilde Valeria
Published: March 2004

We recently published the genomic characterization of the STAT5A and STAT5B paralogous genes that are located head to head in the 17q21 chromosome and share large regions of sequence identity. We here demonstrate by transient in vitro transfection that STAT5A and STAT5B promoters are able to direct comparable levels of transcription. The expression of basal promoters is enhanced after Sp1 up‐regulation in HeLa and SL2 cells while DNA methylation associated to the recruitment of MeCP2 methyl CpG binding protein down‐regulates STAT5A and B promoters by interfering with Sp1‐induced transcription. In addition, cross‐species sequence comparison identified a bi‐directional negative cis‐acting regulatory element located in the STAT5 intergenic region.
Anti‐amyloid activity of neprilysin in plaque‐bearing mouse models of Alzheimer's disease
Authors: Mohajeri M.Hasan , Kuehnle Katrin , Li Hong , Poirier Raphael , Tracy Jay , Nitsch Roger M.
Published: March 2004

Abnormally high concentrations of β‐amyloid peptide (Aβ) and amyloid plaque formation in Alzheimer's disease (AD) may be caused either by increased generation or by decreased degradation of Aβ. Therefore, activation of mechanisms that lower brain Aβ levels is considered valuable for AD therapy. Neuronal upregulation of neprilysin (NEP) in young transgenic mice expressing the AD‐causing amyloid precursor protein mutations (SwAPP) led to reduction of brain Aβ levels and delayed Aβ plaque deposition. In contrast, a comparable increase of brain NEP levels in aged SwAPP mice with pre‐existing plaque pathology did not result in a significant reduction of plaque pathology. Therefore, we suggest that the potential of NEP for AD therapy is age‐dependent and most effective early in the course of AD pathophysiology.
A thermostable manganese‐containing superoxide dismutase from pathogen Chlamydia pneumoniae
Authors: Yu Jing , Yu Xiaomin , Liu Jianhua
Published: March 2004

The gene CP0718 encoding a putative manganese‐containing superoxide dismutase of Chlamydia pneumoniae AR39 was cloned and expressed in Escherichia coli. Characterization showed that the expressed protein with a monomeric molecular mass of 23.1 kDa had superoxide dismutase (SOD) activity and the cofactor of CpSOD was a bivalent manganese cation. It is unexpected that this enzyme was hyperthermostable, and maintained about 90% activity after incubation at 70°C for 60 min. Manganese binding residues found in the SOD sequences from different species are conserved in CpSOD. Bioinformatics analysis compared with Propionibacterium shermanii MnSOD was performed to elucidate the CpSOD hyperthermostability based on amino acid sequences.
Applied jasmonates accumulate extracellularly in tomato, but intracellularly in barley
Authors: Bücking Heike , Förster Hella , Stenzel Irene , Miersch Otto , Hause Bettina
Published: March 2004

Jasmonic acid (JA) and its derivatives are well‐characterized signaling molecules in plant defense and development, but the site of their localization within plant tissue is entirely unknown. To address the question whether applied JA accumulates extracellularly or intracellularly, leaves of tomato and barley were fed with 14C‐labeled JA and the label was localized in cryofixed and lyophilized leaf tissues by microautoradiography. In tomato the radioactivity was detectable within the apoplast, but no label was found within the mesophyll cells. By contrast, in barley leaf tissues, radioactivity was detected within the mesophyll cells suggesting a cellular uptake of exogenously applied JA. JA, applied to leaves of both plants as in the labeling experiments, led in all leaf cells to the expression of JA‐inducible genes indicating that the perception is completed by JA signal transduction.
Effect of N‐acetylglucosaminyltransferase V on the expressions of other glycosyltransferases
Authors: Guo Peng , Zhang Ying , Shen Zong-hou , Zhang Xia-ying , Chen Hui-li
Published: March 2004

Transfection of sense cDNA of N‐acetylglucosaminyltransferase V (GnTV) into H7721 human hepatocellular carcinoma cells resulted in the decreased expression of surface sialyl Lewis X (SLex), a sialylated fucose‐containing antigen. The enzymatic mechanisms were speculated to be the concomitantly decreased expression of α1,3‐fucosyltransferase (FucT)‐III, ‐VI, ‐VII and the branching enzyme of O‐glycans, core 2‐β1,6‐N‐acetylglucosaminyltransferase (C2GnT)‐I, ‐II. These two glycosyltransferase families were suggested to be the key enzymes in the synthesis of SLex. The expression of α2,3‐sialyltransferase (ST3)‐IV, but not ST3‐I, ‐II and ‐III was elevated by sense GnTV. However, it did not cause the increase of SLex synthesis. Transfection of antisense GnTV into H7721 cells showed entirely opposite effects on the expression of above‐mentioned SLex and glycosyltransferases as the sense GnTV.
Immediate response of the DnaK molecular chaperone system to heat shock
Authors: Siegenthaler Rahel K. , Grimshaw John P.A. , Christen Philipp
Published: March 2004

The familiar heat shock response in cells comprises the enhanced expression of molecular chaperones. In recent experiments with the Hsp70 system of Escherichia coli, the co‐chaperone GrpE has been found to undergo a reversible thermal transition in the physiological temperature range. Here, we tested whether this thermal transition is of functional significance in the complete DnaK/DnaJ/GrpE chaperone system. We found that a mere increase in temperature resulted in a higher fraction of fluorescence‐labeled peptides being sequestered by DnaK. This direct adaptation of the DnaK/DnaJ/GrpE chaperone system to heat shock conditions may serve to bridge the time lag of enhanced chaperone expression.
N‐linked glycosylation of platelet P2Y12 ADP receptor is essential for signal transduction but not for ligand binding or cell surface expression
Authors: Zhong Xiaotian , Kriz Ron , Seehra Jasbir , Kumar Ravindra
Published: March 2004

P2Y12 receptor is a Gi‐coupled adenosine diphosphate (ADP) receptor with a critical role in platelet aggregation. It contains two potential N‐linked glycosylation sites at its extra cellular amino‐terminus, which may modulate its activity. Studies of both tunicamycin treatment and site‐directed mutagenesis have revealed a dispensable role of the N‐linked glycosylation in the receptor's surface expression and ligand binding activity. However, the non‐glycosylated P2Y12 receptor is defective in the P2Y12‐mediated inhibition of the adenylyl cyclase activity. Thus the study uncovers an unexpected vital role of N‐linked glycans in receptor's signal transducing step but not in surface expression or ligand binding.
The archaeal sensory rhodopsin II/transducer complex: a model for transmembrane signal transfer
Authors: Klare Johann P , Gordeliy Valentin I , Labahn Jörg , Büldt Georg , Steinhoff Heinz-Jürgen , Engelhard Martin
Published: March 2004

Archaebacterial photoreceptors mediate phototaxis by regulating cell motility through two‐component signalling cascades. Homologs of this sensory pathway occur in all three kingdoms of life, most notably in enteric bacteria in which the chemotaxis has been extensively studied. Recent structural and functional studies on the sensory rhodopsin II/transducer complex mediating the photophobic response of Natronomonas pharaonis have yielded new insights into the mechanisms of signal transfer across the membrane. Electron paramagnetic resonance data and the atomic resolution structure of the receptor molecule in complex with the transmembrane segment of its cognate transducer provided a model for signal transfer from the receptor to the cytoplasmic side of the transducer. This mechanism might also be relevant for eubacterial chemoreceptor signalling.
Screening of functional antidotes of RNA aptamers against bovine thrombin
Authors: Liu Xuemei , Cao Guojun , Ding Hongmei , Zhang Dajin , Yang Guang , Liu Nongle , Fan Ming , Shen Beifen , Shao Ningsheng
Published: March 2004

A specific RNA aptamer (T705) against bovine thrombin had been obtained after seven rounds of SELEX (systematic evolution of ligands by exponential enrichment) selection from a random RNA library previously. In order to further investigate the relationship between the structure and function of this aptamer, three truncated RNA aptamers, T705a, T705b and T705c, were designed according to the secondary structure of T705 RNA. Our results showed that T705c keeping the precise stem–loop structure but lacking most of the stem region sequence of T705 could inhibit clot formation in vitro in the same way as its parental form. We also report here that single‐stranded DNA (ssDNA) antisense oligonucleotides, c′ and c′‐22, which were complementary to different portions of T705c could act as efficient antidotes reversing the inhibitory activity of T705. It is demonstrated for the first time that ssDNA antisense oligonucleotides are potential antidotes of RNA aptamers and this may be an effective, rapid strategy to find antidotes of RNA aptamers which would be of important usefulness in basic research and drug screening.
Gaining insight into the role of serine 282 in B. napus FAE1 condensing enzyme
Authors: Katavic Vesna , Barton Dennis L. , Giblin E.Michael , Reed Darwin W. , Kumar Arvind , Taylor David C.
Published: March 2004

To gain some insight whether there is an absolute requirement for the serine 282 to yield a functional fatty acid elongase 1 condensing enzyme we have introduced point mutations in the FAE1 coding sequence which led to the substitution of serine 282 with several aliphatic or aromatic amino acids. The mutated FAE1 polypeptides were expressed in yeast. Gas chromatography analyses of the fatty acid methyl esters from yeast lysates and fatty acid elongase activity assays demonstrated that there is not an absolute requirement for serine at position 282 to yield a functional FAE1 condensing enzyme.
The crystal structure of the Escherichia coli lipocalin Blc suggests a possible role in phospholipid binding
Authors: Campanacci Valérie , Nurizzo Didier , Spinelli Silvia , Valencia Christel , Tegoni Mariella , Cambillau Christian
Published: March 2004

Lipocalins form a large multifunctional family of small proteins (15–25 kDa) first discovered in eukaryotes. More recently, several types of bacterial lipocalins have been reported, among which Blc from Escherichia coli is an outer membrane lipoprotein. As part of our structural genomics effort on proteins from E. coli, we have expressed, crystallized and solved the structure of Blc at 1.8 Å resolution using remote SAD with xenon. The structure of Blc, the first of a bacterial lipocalin, exhibits a classical fold formed by a β‐barrel and a α‐helix similar to that of the moth bilin binding protein. Its empty and open cavity, however, is too narrow to accommodate bilin, while the alkyl chains of two fatty acids or of a phospholipid could be readily modeled inside the cavity. Blc was reported to be expressed under stress conditions such as starvation or high osmolarity, during which the cell envelope suffers and requires maintenance. These data, together with our structural interpretation, suggest a role for Blc in storage or transport of lipids necessary for membrane repair or maintenance.
Ceramide‐1‐phosphate: a novel regulator of cell activation
Authors: Gómez-Muñoz Antonio
Published: March 2004

Ceramide‐1‐phosphate (Cer‐1‐P) is emerging as a novel bioactive sphingolipid. It is formed by phosphorylation of ceramide catalyzed by ceramide kinase, and has been implicated in different cellular processes. Cer‐1‐P is mitogenic for fibroblasts, blocks apoptosis in macrophages, controls phagocytosis in neutrophils, and mediates inflammatory responses. Only recently have we started to uncover the signaling pathways that are affected by Cer‐1‐P. Recent work has demonstrated that cytosolic phospholipase A2 and acid sphingomyelinase are direct intracellular targets of Cer‐1‐P, and that it may also induce phosphorylation of extracellular signal‐regulated kinase‐2 and calcium mobilization. These actions of Cer‐1‐P seem to be cell type‐specific.
Peroxynitrite formation from the simultaneous reduction of nitrite and oxygen by xanthine oxidase
Authors: Millar Timothy M.
Published: March 2004

One electron reductions of oxygen and nitrite by xanthine oxidase form peroxynitrite. The nitrite and oxygen reducing activities of xanthine oxidase are regulated by oxygen with K
oxygen 26 and 100 μM and K
nitrite 1.0 and 1.1 mM with xanthine and NADH as donor substrates. Optimal peroxynitrite formation occurs at 70 μM oxygen with purine substrates. Kinetic parameters: V
max∼50 nmol/min/mg and K
m of 22, 36 and 70 μM for hypoxanthine, pterin and nitrite respectively. Peroxynitrite generation is inhibited by allopurinol, superoxide dismutase and diphenylene iodonium. A role for this enzyme activity can be found in the antibacterial activity of milk and circulating xanthine oxidase activity.
Ablation of SM22α decreases contractility and actin contents of mouse vascular smooth muscle
Authors: Zeidan Asad , Swärd Karl , Nordström Ina , Ekblad Eva , Zhang Janet C.L. , Parmacek Michael S. , Hellstrand Per
Published: March 2004

The actin‐binding protein SM22α marks contractile differentiation in smooth muscle, but its function is unknown. We tested its role in arterial contractility and stretch‐sensitive vascular protein synthesis. Active stress in depolarised mesenteric resistance arteries and portal veins was reduced by 40% in SM22α−/− mice. Passive and active arterial circumference–force relationships were shifted leftwards, whereas α1‐adrenergic responses were increased. Actin contents were 10–25% lower in vessels from SM22α−/− mice, but protein composition was otherwise similar. Synthesis of SM22α, calponin and α‐actin, but not β‐actin, was sensitive to stretch. Ablation of SM22α did not affect stretch sensitivity of any of these proteins. Thus, SM22α plays a role in contractility, possibly by affecting actin filament organisation.
Formation of circular polyribosomes in wheat germ cell‐free protein synthesis system
Authors: Madin Kairat , Sawasaki Tatsuya , Kamura Nami , Takai Kazuyuki , Ogasawara Tomio , Yazaki Kazumori , Takei Toshiaki , Miura Kin-Ichiro , Endo Yaeta
Published: March 2004

We report a morphological study of functioning ribosomes in a efficient and robust cell‐free protein synthesis system prepared from wheat embryos. Sucrose density gradient analysis of translated mixtures programmed with luciferase mRNAs having different 5′ and 3′ untranslated regions showed formation of large polysomes. Electron microscopic examination of translation mixtures programmed with those of capped and polyadenylated mRNA revealed that ribosomes assemble into a circular‐type polysome in vitro. Furthermore, a series of experiments using mRNAs lacking either cap, poly(A) tail or both also resulted in the formation of circular polysomes, which are indistinguishable from those with the original mRNA. The wheat germ cell‐free system may provide a good experimental system for understanding functional ribosomes at the molecular level.
Lignin dehydrogenative polymerization mechanism: a poplar cell wall peroxidase directly oxidizes polymer lignin and produces in vitro dehydrogenative polymer rich in β‐O‐4 linkage
Authors: Sasaki Shinya , Nishida Tomoaki , Tsutsumi Yuji , Kondo Ryuichiro
Published: March 2004

An investigation was performed to determine whether lignin dehydrogenative polymerization proceeds via radical mediation or direct oxidation by peroxidases. It was found that coniferyl alcohol radical transferred quickly to sinapyl alcohol. The transfer to syringaresinol was slower, however, the transfer to polymeric lignols occurred very slightly. This result suggests that the radical mediator theory does not sufficiently explain the mechanism for dehydrogenative polymerization of lignin. A cationic cell wall peroxidase (CWPO‐C) from poplar (Populus alba L.) callus showed a strong substrate preference for sinapyl alcohol and the sinapyl alcohol dimer, syringaresinol. Moreover, CWPO‐C was capable of oxidizing high‐molecular‐weight sinapyl alcohol polymers and ferrocytochrome c. Therefore, the CWPO‐C characteristics are important to produce polymer lignin. The results suggest that CWPO‐C may be a peroxidase isoenzyme responsible for the lignification of plant cell walls.
A comparison of the Faces Pain Scale and the Facial Affective Scale for children's estimates of the intensity and unpleasantness of needle pain during blood sampling
Authors: Goodenough Belinda , Van Dongen Katinka , Brouwer Nanda , Abu‐Saad Huda H. , Champion G. David
Published: March 2004

To what degree can facial expression scales help children differentiate between the sensory and emotional aspects of the pain experience? This study examined the relationship between children's ratings on the Faces Pain Scale (an intensity measure), the Facial Affective Scale (an affective measure), and a paired mechanical visual analogue (MVAS) method for measuring the intensity and unpleasantness of pain. It was predicted that ratings on the Faces Pain Scale should correlate best with the MVAS measure of pain intensity rather than unpleasantness. Likewise, ratings on the Facial Affective Scale should correlate best with the MVAS measure of pain unpleasantness (assumed to reflect an emotional dimension) rather than intensity. Eighty children scheduled for blood sampling were selected in two age groups: 4 to 6, and 7 to 10 years. Children rated needle pain using each pain scale. As hypothesized, ratings on the Faces Pain Scale correlated more highly with the MVAS ratings for intensity (r = 0.77) than for unpleasantness (r = 0.52). A smaller reverse finding was confirmed for the Facial Affective Scale which correlated more highly with the MVAS for unpleasantness (r = 0.64) than for intensity (r = 0.51). Factor analysis indicated that ‘pain dimension’ (intensity vs affect) was a relatively weak factor as compared with shared instrument variance (two MVAS vs two face scales). No systematic age effects were observed. In conclusion, the Faces Pain Scale and the Facial Affective Scale may partly measure different aspects of the pain experience in children, although it remains to be determined to what degree the obtained differences are clinically meaningful.
Impaired selective attention in chronic pain patients
Authors: Grisart Jacques M. , Plaghki Leon H.
Published: March 2004

Several recent studies have suggested that cognitive complaints among chronic pain patients could result from an interference between ongoing pain and mental tasks, as they share common and limited attentional resources. This study was intended to further explore that presumed relationship between chronic pain and attentional disorders. For this purpose, a more sensitive version of the conventional colour‐word Stroop task, with four subtasks of increasing difficulty, was used in a group of 33 consecutive patients with chronic nonmalignant pain and a group of 20 healthy subjects as controls. This task assesses specifically selective attention. Since the Stroop task is sensitive to dysthymic states, levels of anxiety and depression were also assessed in chronic pain patients.

As expected, the increase of response times was positively related to the difficulty of the subtasks. However, only the patients with chronic pain of high intensity presented a significant increase in the response times to each subtask as compared to controls. Response accuracy was not affected. Patients with high pain had higher scores on trait‐anxiety than those with low‐intensity pain. However, ANCOVA showed that trait‐anxiety scores × pain groups interactions were not significant and thus that trait‐anxiety was not useful for predicting task performance.

These results point to a disturbance of selective attention as a function of pain intensity in chronic pain patients.
Principles of economic evaluation for interventions of chronic musculoskeletal pain
Authors: Goossens Mariëlle E.J.B. , Evers Silvia M.A.A. , Vlaeyen Johan W.S. , Mölken Maureen P.M.H. Rutten‐van , van der Linden Sjef M.J.P.
Published: March 2004

Economic evaluation is attracting increasing attention to inform policy makers, insurers and other payers of the value of existing and new treatment modalities. Hence, it is desirable to assess not only the medical but also the economic consequences the new treatments produce. The available literature on economic evaluation revealed an urgent need for sound economic evaluation studies in the field of chronic musculoskeletal pain. Due to the generally weak methodology, the intended purpose of economic evaluation to help set funding priorities has often been bypassed. Although in general therapists have no direct responsibility for allocating scarce resources in the field of musculoskeletal pain, they are confronted with the results of these decisions in their everyday work. A clear understanding of the main principles of economic evaluation studies might therefore be advantageous. This paper addresses important methodological issues in economic evaluation research, such as the techniques for economic evaluation studies and the analytic perspective. In addition, the paper pays attention to the inclusion of costs and outcomes in economic evaluation research, sensitivity analysis, discounting, incremental analysis and ratios, and collecting of data.

Further emphasis is placed on the transparent reporting of methods and study results. A clear reporting may help therapists and other researchers interpret the results of published studies and apply them to their own studies, and it may help decision makers generalize results from one setting to another.
Opposite effects of spinal cord stimulation in different phases of carrageenan‐induced hyperalgesia
Authors: Cui Jian‐Guo , Meyerson Björn A. , Linderoth Bengt
Published: March 2004

A possibly beneficial effect of spinal cord stimulation (SCS) on acute and chronic nociceptive pain is still a controversial issue. In the present experimental study, SCS was applied, with parameters similar to those used clinically, to awake but restrained rats submitted to intraplantar injection of carrageenan (CAR). The paw circumference and the threshold of paw withdrawal and/or vocalization to pressure, applied by a pair of strain gauge calibrated flat forceps to the paw, were determined before and after CAR injection. As controls, one group of rats was treated by CAR injection only; a second group was subjected to SCS after CAR injection; a third group was pretreated with SCS for 3 days before the injection; a fourth group subjected to SCS only. In the acute phase, 3 h after the injection, SCS enhanced the CAR‐induced hyperalgesia and oedema. Conversely, in the subacute phase at day 3–5 after the injection, SCS suppressed the hyperalgesia which was, however, less marked than in the acute phase. However, in that phase, the oedema was still increased by SCS. Pretreatment by SCS influenced neither the natural time course of hyperalgesia nor that of oedema. Circumstantial evidence suggests that the oedema augmentation by SCS in the acute phase may be the result of enhanced vasodilatation with fluid extravasation, probably associated with peripheral release of several substances, such as CGRP. The concomitant increase of the hyperalgesia may reflect an enhanced release of substance P and 5‐HT, both peripherally and in the dorsal horn. The attenuation of hyperalgesia in the subacute phase may be due to an inhibitory effect of SCS on A‐fibre‐mediated wide‐dynamic‐range neuronal hyperactivity, presumably involving GABAergic mechanisms. However, a direct suppressive effect on sensitized nociceptive‐specific second‐order neurons cannot be excluded.
Palliative care in the past decade and today
Authors: Twycross Robert G.
Published: March 2004

The essence, principles, and philosophy of palliative care are timeless. However, the evolution of new concepts and the development of new therapeutic approaches have enhanced our ability to translate the principles of palliative care into practice. For example, new insights into the different pathways of action of the two variants of the cyclo‐oxygenase enzyme may ultimately permit the development of non‐steroidal anti‐inflammatory drugs with minimal adverse gastrointestinal events. In addition, we now understand that the different clinical effects of various opioids reflect the different affinities of these drugs for occupying and activating μ, κ, and Δ‐opioid receptors. Antagonists and blockers of the N‐methyl‐d‐aspartate glutamate receptor‐channel show promise for treating neuropathic pain. The introduction of modified‐release opioids and of new devices that permit the long‐term delivery of spinal analgesia have also opened up new possibilities in the management of pain. A transdermal formulation of fentanyl, which causes less constipation and possibly less nausea than morphine, may have the potential to enhance the quality of life for patients with terminal disease.
Gene therapy for Parkinson's disease
Authors: Lawlor Patricia A. , During Matthew J.
Published: March 2004

Parkinson's disease (PD) is a debilitating neurodegenerative disorder arising from loss of dopaminergic neurons in the substantia nigra pars compacta and subsequent depletion of striatal dopamine levels, which results in distressing motor symptoms. The current standard pharmacological treatment for PD is direct replacement of dopamine by treatment with its precursor, levodopa (L-dopa). However, this does not significantly alter disease progression and might contribute to the ongoing pathology. Several features of PD make this disease one of the most promising targets for clinical gene therapy of any neurological disease. The confinement of the major pathology to a compact, localised neuronal population and the anatomy of the basal ganglia circuitry mean that global gene transfer is not required and there are well-defined sites for gene transfer. The multifactorial aetiology of idiopathic PD means that it is unlikely any single gene will cure the disease, and as a result at least three separate gene-transfer strategies are currently being pursued: transfer of genes for enzymes involved in dopamine production; transfer of genes for growth factors involved in dopaminergic cell survival and regeneration; and transfer of genes to reset neuronal circuitry by switching cellular phenotype. The merits of these strategies are discussed here, along with remaining hurdles that might impede transfer of gene therapy technology to the clinic as a treatment for PD.