bluuebunny/crossref_metadata_2025 huggingface dataset:
New chromogenic dipeptide substrate for continuous assay of the d‐alanyl‐d‐alanine dipeptidase VanX required for high‐level vancomycin resistance
Authors: Anissimova M. , Yaouancq L. , Badet‐Denisot M.‐A. , Badet B.
Published: June 2003

Abstract: A direct continuous UV–Vis spectrophotometric assay has been developed for VanX, a d‐alanyl‐d‐alanine aminodipeptidase necessary for vancomycin resistance. This method is based on the hydrolysis of the alternative substrate d‐alanyl‐α‐(R)‐phenylthio‐glycine d‐Ala‐d‐Gly(S‐Ph)‐OH (H‐dAla‐dPsg‐OH, 5a). Spontaneous decomposition of the released phenylthioglycine generates thiophenol, which is quantified using Ellman's reagent. The dipeptide behaved as an excellent substrate of VanX, exhibiting Michaelis–Menten kinetics with a kcat of 76 ± 5/s and a KM of 0.83 ± 0.08 mm (kcat = 46 ± 3/s and KM = 0.11 ± 0.01 mm for d‐Ala‐d‐Ala). Determination of the kinetic parameters of the previously reported mechanism‐based inhibitor d‐Ala‐d‐Gly(SΦp‐CHF2)‐OH (H‐d‐Ala‐dPfg‐OH, 5c) [Araoz, R., Anhalt, E., René, L., Badet‐Denisot, M.‐A., Courvalin, P. & Badet, B. (2000) Biochemistry39, 15971–15979] using the substrate reported in the present study yielded values of Kirr of 22 ± 1 μm and kinact of 9.3 ± 0.4/min in good agreement with values previously obtained in our laboratory (Kirr = 30 ± 1 mm; kinact = 7.3 ± 0.3/min). In addition, inhibition by the competing substrate d‐Ala‐d‐Ala resulted in determination of a Ki = 70 ± 6 μm close to the previously reported KM value. These results demonstrate that the present assay is a convenient, rapid and sensitive tool in the search for VanX inhibitors.
Conformation of the transmembrane domains in peripheral myelin protein 22. Part 1. Solution‐phase synthesis and circular dichroism study of protected 17‐residue partial peptides in the first putative transmembrane domain*
Authors: Yamada K. , Sato J. , Oku H. , Katakai R.
Published: June 2003

Abstract:  Charcot‐Marie‐Tooth disease (CMT) is the most commonly inherited peripheral neuropathy. DNA duplication and point mutation of the gene encoding peripheral myelin protein 22 (PMP22) have been found in CMT type 1A dominants. To investigate the influence of the point mutation of PMP22 on the secondary structure, protected partial peptides in the putative first transmembrane domain, wild type Boc‐IVLH(Bom)VAVLVLLFVSTIV‐OMe (1) and its Pro16 mutant Boc‐IVLH(Bom)VAVPVLLFVSTIV‐OMe (2) were synthesized. Circular dichorism (CD)‐spectral analysis suggested that peptide 1 adopts a stable α‐helical conformation in membrane‐mimetic solvent,1‐BuOH/1,1,1,3,3,3‐hexafluoro‐2‐propanol (HFIP) system. On the contrary, the mutant 2 favors β‐sheet conformation in the same solvent system. Interestingly, α‐helix to β‐sheet transition of 2 was observed at higher contents of 1‐BuOH than 70%.
Catatonia and other psychiatric symptoms with vitamin B12 deficiency
Authors: Berry N. , Sagar R. , Tripathi B. M.
Published: June 2003

Objective: To study unusual psychiatric manifestation of vitamin B12 deficiency and related issues.

Method: A case study of 52‐year‐old female and review of relevant literature.

Results: Complete remission of psychiatric symptoms without recurrence for the next 4 years with vitamin B12 as the only specific therapy instituted.

Conclusion: Importance of B12 estimation and replacement in patients with varied psychiatric manifestations.
Cognitive remediation of working memory deficits: durability of training effects in severely impaired and less severely impaired schizophrenia
Authors: Bell M. , Bryson G. , Wexler B. E.
Published: June 2003

Objective: To determine whether augmenting work therapy (WT) with neurocognitive enhancement therapy (NET) yields greater improvement in working memory performance than WT alone and whether there is an interaction with severity of impairment.

Method: A total of 102 participants with schizophrenia or schizoaffective disorder were categorized as severely or less severely cognitively impaired and randomly assigned to receive NET + WT or WT alone. NET consisted of cognitive training exercises in attention, memory, executive function, and social information processing, and WT was a 6‐month work program.

Results: Comparison on Digits Backwards from intake to follow‐up revealed significantly greater improvement for participants receiving NET + WT, but there was no interaction with severity group. Follow‐up 6 months after training showed that training effects endured.

Conclusion: NET + WT improved working memory for most participants regardless of impairment severity. Intensity and duration of training may have contributed to duration of effects. Findings support continued exploration of cognitive remediation.
Alterations in theory of mind in patients with schizophrenia and non‐psychotic relatives
Authors: Janssen I. , Krabbendam L. , Jolles J. , Van Os Jim
Published: June 2003

Objective: It has been proposed that alterations in theory of mind underlie specific symptoms of psychosis. The present study examined whether alterations in theory of mind reflect a trait that can be detected in non‐psychotic relatives of patients with schizophrenia.

Method: Participants were 43 patients with schizophrenia or schizoaffective disorder, 41 first‐degree non‐psychotic relatives and 43 controls from the general population. Theory of mind was assessed using a hinting task and a false‐belief task.

Results: There was a significant association between schizophrenia risk and failure on the hinting task (OR linear trend = 2.01, 95% CI: 1.22–3.31), with relatives having intermediate values between patients and controls. Adjustment for IQ and neuropsychological factors reduced the association by small amounts. The association between schizophrenia risk and failure on the false‐belief tasks was not significant.

Conclusion: Changes in theory of mind are associated with schizophrenia liability. General cognitive ability and neuropsycholo‐ gical measures seem to mediate only part of this association.
Personality and self‐variables: important determinants of subjective quality of life in schizophrenia out‐patients
Authors: Eklund M. , Bäckström M. , Hansson L.
Published: June 2003

Objective: To investigate factors determining severely mentally ill patients’ self‐rated quality of life. The study hypothesized that objective life circumstances, personality, self‐variables, and psychopathology would be determinants of quality of life.

Method: A total of 117 individuals with schizophrenia and related disorders were investigated. Structural equation modelling was used to: 1) investigate if one or more subfactors best described the covariance within each potential determinant and quality of life, 2) explore the relations between all variables and factors extracted in step 1.

Results: A multi‐factorial model indicated that a self‐factor and two psychopathology factors worked as mediators of self‐rated quality of life, in turn composed of an internal and an external aspect. Personality dimensions and objective life circumstances accounted directly or indirectly for substantial parts of quality of life.

Conclusion: The relative importance of individual characteristics and objective indices was shown. Trait‐like properties, such as the self‐factor and personality, explained most of the variation in self‐rated quality of life.
Anomalies of subjective experience in schizophrenia and psychotic bipolar illness
Authors: Parnas J. , Handest P. , Sæbye D. , Jansson L.
Published: June 2003

Objective: Contemporary psychopathology, as a result of behaviourally dominated epistemological stance, downplays anomalies of the patient's subjectivity. This neglect has probably deleterious consequences for research in the causes and the boundaries of the schizophrenia spectrum conditions. The purpose of this study is to explore frequency of qualitative, not‐yet‐psychotic, anomalies of subjective experience in patients with residual schizophrenia and psychotic bipolar illness in remission.

Method: The patients were examined with the Danish version of the Bonn Scale for the Assessment of Basic Symptoms (BSABS). Anomalies of experience were condensed into rational scales with good internal consistencies.

Results: Diagnosis of schizophrenia was associated with elevated scores on the scales measuring perplexity (loss of immediate meaning), disorders of perception, disorders of self‐awareness, and marginally so, disorders of cognition.

Conclusion: These findings, in conjunction with those from other, methodologically similar studies, suggest that certain anomalies of subjective experience aggregate significantly in schizophrenia. These experiential anomalies appear to be relevant for early differential diagnosis and therefore potentially useful in the preonset detection of the schizophrenia spectrum illness.
A 20‐year follow‐up study on schizophrenia in Singapore
Authors: Kua J. , Wong K. E. , Kua E. H. , Tsoi W. F.
Published: June 2003

Objective: To assess the outcome and predictors of patients with schizophrenia 20 years later.

Method: The patients, aged 15–39 years, with diagnosis of schizophrenia and first admitted to a national mental hospital in Singapore in 1975 were included. In 1980, 1985, 1990 and 1995, their hospital records were examined and the patients were interviewed to determine their working and treatment status. Possible predictors of good outcome and suicide data were determined.

Results: A total of 402 patients were included. Over 20 years, there was lower percentage of patients working full time and proportionately more patients were receiving out‐patient treatment. Overall, about two‐third of the patients had a good/fair outcome. Shorter illness duration before admission was significantly associated with a good outcome. The suicide rate was the highest in the first 10 years.

Conclusion: Most patients with schizophrenia had a good/fair outcome at 20 years.
Neurological soft signs in never‐treated schizophrenia
Authors: Venkatasubramanian G. , Latha V. , Gangadhar B. N. , Janakiramaiah N. , Subbakrishna D. K. , Jayakumar P. N. , Keshavan M. S.
Published: June 2003

Objective:Studies of Neurological Soft Signs (NSS) in schizophrenia are confounded by handedness, inconsistent methodology, and prior treatment with neuroleptics. The study objective is to examine NSS in never‐treated schizophrenia.

Method:We examined the NSS in treatment‐naïve schizophrenia patients (n = 21) and age, sex, education, and handedness matched normal controls (n = 21) using the modified Neurological Evaluation Scale with good inter‐rater reliability.

Results:Schizophrenia patients had significantly more NSS than normals. No significant correlation was found between illness duration and NSS.

Conclusion:Higher neurological signs in never‐treated patients and their lack of association with illness duration suggest neurodevelopmental etiopathogenesis of schizophrenia.
Association between minor physical anomalies and lateral ventricular enlargement in childhood and adolescent onset schizophrenia
Authors: Hata K. , Iida J. , Iwasaka H. , Negoro H. , Kishimoto T.
Published: June 2003

Objective: The primary purpose of this study was to investigate the association between morphological abnormalities of brain and minor physical anomalies (MPAs) in childhood and adolescent onset schizophrenia.

Method: Twenty‐seven patients who had been diagnosed with schizophrenia according to DSM‐IV criteria before 18 years of age were included in the study. MPAs were evaluated with the modified version of Waldrop scale (WS) by Green et al. Morphological abnormalities of brain was evaluated with ventricular‐brain ratio (VBR) by using cerebral magnetic resonance imaging (MRI) examination.

Results: A significant positive correlation was observed between WS scores and VBRs.

Conclusion: This result indicates a relationship between MPAs and lateral ventricular enlargement, and supports neurodevelopmental etiology in childhood or adolescent onset schizophrenia.
The neurology of learning and behavioural problems in pre‐adolescent children
Authors: Batstra L. , Neeleman J. , Hadders‐Algra M.
Published: June 2003

Objective: The aim of the study was to evaluate whether in pre‐adolescent children specific types of minor neurological dysfunction (MND) are related to specific types of learning and behavioural problems, and whether it is the type or the severity of neurological dysfunction that matters most.

Method: A total of 1186, 5.5–11‐year‐old, children were examined for the presence of clusters of signs of MND. Parents and teachers completed brief behaviour rating scales. In school‐aged children (n = 580) cognitive achievement was assessed using standardized Dutch tests. Least‐squares regression was used to examine neurobehavioural and neurocognitive links.

Results: Children with more MND clusters performed worse scholastically and had more signs of attention deficit than others. Externalizing and internalizing behaviour were only linked to specific forms of MND.

Conclusion: Evaluation of the neurological condition of the child with learning and behavioural problems offers insight into the aetiology and pathogenesis of these problems.
Neuropsychological and neurophysiological findings in individuals suspected to be at risk for schizophrenia: preliminary results from the Basel early detection of psychosis study – Früherkennung von Psychosen (FEPSY)
Authors: Gschwandtner U. , Aston J. , Borgwardt S. , Drewe M. , Feinendegen C. , Lacher D. , Lanzarone A. , Stieglitz R.‐D. , Riecher‐Rössler A.
Published: June 2003

Objective: Our study aims to establish a scientific basis for the very early detection of patients at risk for schizophrenia during the nonspecific prodromal phase of the disorder and to predict its outbreak.

Method: A multidomain approach is used. After screening, approved psychopathological, neurophysiological, neuropsychological and neuroradiological investigations are used to assess a sample of individuals suspected to be at risk for schizophrenia.

Results: Neuropsychological and fine motor functioning tests as well as eye movement measurements showed statistically significant differences (P<0.01) between individuals suspected to be at risk for schizophrenia and healthy controls.

Conclusion: Individuals suspected to be at risk for schizophrenia show specific impairments in various investigations including neuropsychological and fine motor functioning tests as well as eye movement measurements. A set of methods sensitive to even subtle changes in normal functioning may prove useful in predicting the subsequent outbreak of schizophrenia.
Serious psychiatric and neurological adverse effects of herbal medicines – a systematic review
Authors: Ernst E.
Published: June 2003

Objective: Psychiatric and neurological patients frequently try herbal medicines often under the assumption that they are safe. The aim of this systematic review was to provide a summary of recent data on severe psychiatric and neurological adverse effects of herbal remedies.

Method: Computerized literature searches were carried out to identify all reports of psychiatric and neurological adverse effects associated with herbal medicines. These data were subsequently extracted, validated and summarized in narrative and tabular form.

Results: Numerous case reports comprise a diverse array of adverse events including cerebral arteritis, cerebral oedema, delirium, coma, confusion, encephalopathy, hallucinations, intracerebral haemorrhage, and other types of cerebrovascular accidents, movement disorders, mood disturbances, muscle weakness, paresthesiae and seizures. Several fatalities are on record. They are caused by improper use, toxicity of herbal ingredients, contamination and adulteration of preparations and herb/drug interactions.

Conclusion: Herbal medicines can cause serious psychiatric and neurological adverse effects.
Topical ascorbic acid on photoaged skin. Clinical, topographical and ultrastructural evaluation: double‐blind study vs. placebo
Authors: Humbert Philippe G. , Haftek Marek , Creidi Pierre , Lapière Charles , Nusgens Betty , Richard Alain , Schmitt Daniel , Rougier André , Zahouani Hassan
Published: June 2003

Abstract:  Vitamin C is known for its antioxidant potential and activity in the collagen biosynthetic pathway. Photoprotective properties of topically applied vitamin C have also been demonstrated, placing this molecule as a potential candidate for use in the prevention and treatment of skin ageing.

A topically applied cream containing 5% vitamin C and its excipient were tested on healthy female volunteers presenting with photoaged skin on their low‐neck and arms in view to evaluate efficacy and safety of such treatment. A double‐blind, randomized trial was performed over a 6‐month period, comparing the action of the vitamin C cream vs. excipient on photoaged skin. Clinical assessments included evaluation at the beginning and after 3 and 6 months of daily treatment. They were performed by the investigator and compared with the volunteer self assessment. Skin relief parameters were determined on silicone rubber replicas performed at the same time‐points. Cutaneous biopsies were obtained at the end of the trial and investigated using immunohistochemistry and electron microscopy. Clinical examination by a dermatologist as well as self‐assessment by the volunteers disclosed a significant improvement, in terms of the ‘global score’, on the vitamin C‐treated side compared with the control. A highly significant increase in the density of skin microrelief and a decrease of the deep furrows were demonstrated. Ultrastructural evidence of the elastic tissue repair was also obtained and well corroborated the favorable results of the clinical and skin surface examinations.

Topical application of 5% vitamin C cream was an effective and well‐tolerated treatment. It led to a clinically apparent improvement of the photodamaged skin and induced modifications of skin relief and ultrastructure, suggesting a positive influence of topical vitamin C on parameters characteristic for sun‐induced skin ageing.
SPR1 gene near HLA‐C is unlikely to be a psoriasis susceptibility gene
Authors: Chang Y. T. , Tsai S. F. , Lin M. W. , Liu H. N. , Lee D. D. , Shiao Y. M. , Chin P. J. , Wang W. J.
Published: June 2003

Abstract:  Although genetics analyses have identified the HLA‐Cw6 allele to be the major risk allele for psoriasis vulgaris (PV) in many racial groups, it has been proposed that other putative genes near the HLA‐C locus are involved in PV susceptibility and that the association of Cw6 is a result of linkage disequilibrium. The SPR1 gene, a predicted gene located 128 kb telomeric to the HLA‐C locus, is considered to be one potential candidate gene of PV. Until now, no association study of the SPR1 gene has been conducted on psoriasis patients. We investigated the SPR1 gene for disease association by direct sequencing of the SPR1 gene in 116 Chinese patients with PV and 116 normal subjects. Genotyping for HLA‐Cw6 was also carried out using polymerase chain reaction/restriction fragment length polymorphism. Significant increase of the HLA‐Cw6 allele was found in psoriasis patients (32.8% vs. 13.8%, P = 0.001). We found that the SPR1 gene is a highly polymorphic gene containing 13 single nucleotide polymorphisms (SNPs), two of which have not been previously reported, and four SNPs cause amino acid change. No significantly different allelic distribution of 13 SPR1 SNPs could be found between the patients with PV and controls after correction for multiple testing. If the frequencies of SPR1 SNPs were compared between the early onset psoriatics and control subjects, early onset patients were more likely to have G allele at position 988 (60% vs. 35.3%, P = 0.001). However, the significance disappeared upon stratification for the Cw6 status. Haplotype‐based association analysis showed two susceptibility haplotypes (types 8 and 19) in early onset psoriasis patients. Nonetheless, the significance also disappeared after stratification of the Cw6 status. Our results suggest that HLA‐Cw6 remains the major risk allele in Chinese psoriatics, and that the SPR1 gene might not play an important role in the causation of PV.
Role for Id‐1 in immunobiology of normal keratinocytes and in basal cell carcinoma
Authors: Chaturvedi Vijaya , Bonish Brian , Bacon Patricia , Qin Jian‐Zhong , Denning Mitchell F. , Foreman Kimberly , Diaz Manuel O. , Robinson June , Nickoloff Brian J.
Published: June 2003

Abstract:  It has been established that Id proteins can block the basic helix–loop–helix (HLH) transcription factors, thereby impacting the onset of senescence in keratinocytes, as well as influencing tumorigenesis involving squamous cell carcinomas. However, the ability of Id‐1 to influence the immunologic response of epithelial cells to cytokines implicated in cutaneous oncology such as gamma interferon (IFN‐γ) has not been determined. Using a whole population of human keratinocytes infected with a retrovirus to induce over‐expression of Id‐1, the influence on early differentiation of rapidly proliferating keratinocytes was assessed, as was the response to IFN‐γ. While induction of involucrin, a marker of early differentiation, was not altered in Id‐1 overexpressing keratinocytes, the IFN‐γ mediated increase in intercellular adhesion molecule‐1 (ICAM‐1) and HLA‐DR was reduced. No change in constitutive or inducible levels of MHC class I antigen, CD95 (Fas antigen) or LFA‐3 (CD58) was observed in this system. Immunostaining and Western blot analysis revealed over‐expression of Id‐1 in basal cell carcinomas (BCCs). These tumors not only strongly and diffusely expressed Id‐1, but were also characterized by reduced ICAM‐1 and HLA‐DR expression. Thus, dysregulated Id‐1 may not only contribute to delaying the senescence program in keratinocytes, it may also contribute to the escape of the relatively undifferentiated tumor cells in BCC from immune surveillance.
Increased epidermal functioning wild‐type p53 expression in vitiligo
Authors: Schallreuter Karin U. , Behrens‐Williams Stefanie , Khaliq Tahira P. , Picksley Steven M. , Peters Eva M. J. , Marles Lee K. , Westerhof Wiete , Miehe Bärbel , Fanghänel Jochen
Published: June 2003

Abstract:  Despite the lack of protective melanin and increased oxidative stress due to mM concentrations of epidermal H2O2 in vitiligo, there is no significantly increased risk for chronic actinic damage and non‐melanoma skin cancer. Therefore the question arises, which protective mechanisms could be involved in the skin of these patients preventing the initiation of these cancers. Recently an overexpression of p53 has been shown in vitiligo. Unfortunately there was no further characterization of this elevated p53. Employing a functional colour yeast assay, the study presented herein demonstrates for the first time the overexpression of a functioning wild‐type p53 protein in both depigmented and ‘normal’ pigmented epidermis of patients with vitiligo compared with healthy controls. Surprisingly long‐term narrowband UVB (311 nm) treatment does not alter this expression. Moreover, MDM‐2, PCNA and p21 protein expression remain unchanged compared with healthy controls. This increased epidermal p53 in vitiligo coincides with decreased thioredoxin reductase (TR) protein levels in both depigmented and pigmented skin whereas mRNA expression is unaffected. Because TR is one transcriptional target of p53, these results support a wild‐type functionality, which was further supported by the specific p53 FASAY yeast test. To our knowledge this is the first example of persistent elevated functioning wild‐type p53 in humans. Based on our results we hypothesize that the low incidence for actinic damage, basal cell and squamous cell carcinoma as documented in vitiligo could well reside in a protective function of up‐regulated wild‐type p53.
Communication network in the follicular papilla and connective tissue sheath through gap junctions in human hair follicles
Authors: Iguchi Makiko , Hara Masahiro , Manome Hideaki , Kobayasi Hiromi , Tagami Hachiro , Aiba Setsuya
Published: June 2003

Abstract: Epithelial–mesenchymal interactions play a crucial role in the induction of life‐long cyclic transformations of hair follicles. Many studies have already demonstrated several candidates for the soluble factors secreted from the mesenchymal components of the hair follicle, i.e. the follicular papilla (FP) and connective tissue sheath (CTS), which may be responsible for hair cycling. In this paper, we focused on cell‐cell contact between FP cells (FPCs), between CTS cells (CTSCs), and between FPCs and CTSCs that may allow these mesenchymal components to function as a syncytium during hair cycling. Electron microscopic examination of the FP and the CTS obtained from human scalp revealed a tri‐lamellar structure of the plasma membranes, which is a characteristic of gap junctions at the cell‐cell contacting area. The immunohistochemical study with anticonnexin 43 Ab using a confocal laser scanning microscope demonstrated numerous spotted positive signals scattered throughout the FP. In the CTS, spotted positive signals were arranged linearly along the basement membrane of the hair follicle. In particular, these positive spots were aggregated in the transitional region between the FP and the CTS. By Western blot analysis of total protein extracts from the cultured FPCs and neonatal human dermal fibroblasts using anticonnexin 43 antibody, a positive band corresponding to connexin 43 was detected at 43 kDa on both the FPC lane and fibroblast lane. These findings suggest that the FP and the CTS form a communicating network through gap junctions, which may play a role in controlling the dynamic structural changes of hair follicles during hair cycling.
Identification of two novel nonsense mutations in the transglutaminase 1 gene in a Hungarian patient with congenital ichthyosiform erythroderma
Authors: Becker K. , Csikós M. , Sárdy M. , Szalai ZS. , Horváth A. , Kárpáti S.
Published: June 2003

Abstract: Congenital ichthyosiform erythroderma (CIE) belongs together with lamellar ichthyosis (LI) to the group of autosomal recessive congenital ichthyoses (ARCI). Mutations in the transglutaminase (TGase) 1 gene (TGM1) have been identified in several families with LI and in some families with CIE. We report a case of CIE with two new nonsense mutations: a C7780G transversion in exon 11 resulting in a premature stop codon at aminoacid residue Y503X and a C8533G transversion in exon 13 leading to a nonsense mutation at S669X. These mutations were also identified in a heterozygous pattern in the unaffected parents. These two termination‐codons result in the translation of a truncated protein at the C‐terminal end domain of the TGM 1 molecule. B.C1 monoclonal antibody failed to detect TGase 1 in the patient's skin sample, and TGase activity measured by monodansyl cadaverine‐incorporation showed the reduced TGase activity at the distribution of TGase 1 in the epidermis.
Combined use of SSRIs and NSAIDs increases the risk of gastrointestinal adverse effects
Authors: De Jong Jeroen C. F. , Van Den Berg Paul B. , Tobi Hilde , De Jong Lolkje T. W. , Van Den Berg ‐
Published: June 2003

Aims  To investigate the relationship between the use of antidepressants with or without NSAIDs and the risk of gastrointestinal side‐effects.

Methods  This was a population‐based cohort study. Medication data of 180 000 patients from 16 pharmacies in The Netherlands were studied. The subjects were a group of 15 445 new users of antidepressants with or without NSAIDs. A review of patient profiles for cases of gastrointestinal adverse effects caused by first time use of antidepressants with or without NSAIDs was carried out. The number of first prescriptions for peptic ulcer drugs (Anatomical Therapeutic Chemical classification A02B) in the period from day 2 after starting antidepressants with or without NSAIDs until 10 days after the last dose was the main outcome measure.

Results  In the reference group of 619 new users of nonselective antidepressants (TCAs), the incidence of first prescriptions for peptic ulcer drugs was 0.051 (95% confidence interval 0.021, 0.105). The use of SSRIs (n = 1181) caused a slightly higher incidence rate ratio (IRR) of 1.2 (0.5, 2.8). The combined use of SSRIs and NSAIDs (n = 86) increased the IRR to 12.4 (3.2, 48.0). In contrast, the combination of nonselective antidepressants and NSAIDs (n = 74) increased the IRR to 2.5 (0.3, 20.3).

Conclusions  SSRIs increase the risk of gastrointestinal adverse effects in first time users as compared with nonselective antidepressants. The combined use of SSRIs and NSAIDs strongly increases the risk of gastrointestinal adverse effects and should be avoided. The combination of nonselective antidepressants and NSAIDs does not have this effect.
Population pharmacokinetics of levosimendan in patients with congestive heart failure
Authors: Jonsson E. Niclas , Antila Saila , McFadyen Lynn , Lehtonen Lasse , Karlsson Mats O.
Published: June 2003

Aims  The aim of this study was to characterize the population pharmacokinetics of levosimendan in patients with heart failure (NYHA grades III and IV) and its relationship to demographic factors, disease severity and concomitant use of digoxin and β‐blocking agents.

Methods  Data from two efficacy studies with levosimendan administered by intravenous infusion were combined (190 patients in total). The data were analysed using a nonlinear mixed‐effects modelling approach as implemented in the NONMEM program. The model development was done in three sequential steps. First the best structural model was determined (e.g. a one‐, two‐ or three‐compartment pharmacokinetic model). This was followed by the identification and incorporation of important covariates into the model. Lastly the stochastic part of the model was refined.

Results  A two‐compartment model best described levosimendan pharmacokinetics. Clearance and the central volume of distribution were found to increase linearly with bodyweight. No other covariates, including concomitant use of digoxin and β‐blocking agents, influenced the pharmacokinetics. In the final model, a 76‐kg patient was estimated to have a clearance ± s.e. of 13.3 ± 0.4 l h−1 and a central volume of distribution of 16.8 ± 0.79 l. The interindividual variability was estimated to be 39% and 60% for clearance and central volume of distribution, respectively. Weight changed clearance by 1.5% [95% confidence interval (CI) 0.9%, 2.1%] and the central volume of distribution by 0.9% (95% CI 0.5%, 1.3%) per kg.

Conclusions  The population pharmacokinetics parameters of levosimendan in this patient group were comparable to those obtained by traditional methods in healthy volunteers and patients with mild heart failure. Bodyweight influenced the clearance and the central volume of distribution, which in practice is accounted for by weight adjusting doses. None of the other covariates, including digoxin and β‐blocking agents, significantly influenced the pharmacokinetics of levosimendan.
Comparison of the micro‐ and macro‐vascular effects of glimepiride and gliclazide in metformin‐treated patients with Type 2 diabetes: a double‐blind, crossover study
Authors: Dhindsa Pash , Davis Karl R. , Donnelly Richard
Published: June 2003

Aims  To compare the metabolic and vascular effects of two sulphonylureas (SU), gliclazide (specific for the pancreatic [SUR1] receptor) and glimepiride (a nonspecific agent that also binds to vascular and cardiac [SUR2] receptors), during chronic administration in metformin‐treated patients with Type 2 diabetes (T2DM).

Methods  A randomized, double‐blind, crossover study of gliclazide 80 mg BID and glimepiride 2 mg OD, each for 4 weeks as add‐on therapy to metformin, with a 4‐week washout period. Patients attended four study mornings after first dose and 4 weeks’ SU treatment for measurements of arterial distensibility (Ax), pressor responsiveness to i.v. angiotensin II (ANGII), and cutaneous microvascular vasodilator responses to iontophoresis of acetylcholine (ACh) and sodium nitroprusside (SNP).

Results  Glycaemic responses were similar (e.g. serum fructosamine was 315 vs 329 µmol l−1 after 4 weeks), and there was no change in augmentation index during treatment with either SU (9.1 vs 9.8 mmHg after 4 weeks [95% confidence interval −8.1, 10.5]). Similarly, there were no differences between treatments in pressor responsiveness (e.g. PD10[dose of agonist required to increase mean BP by 10 mmHg] for ANGII was 1.37 vs 1.68 ng kg−1 min−1[−4.3, 6.9]) or cutaneous microvascular vasodilator responses (peak ACh response 68 ± 36 vs 63 ± 34 perfusion units [−82.7, 79.1]).

Conclusions  There is no evidence that SUR1‐specific and nonspecific SUs have differential effects on arterial distensibility, endothelial function or vasodilator mechanisms in metformin‐treated patients with T2DM.
Population pharmacokinetics of netilmicin in short‐term prophylactic treatment
Authors: Jauregizar Nerea , Wald Jeff A. , Astobieta Ander , Sasiain Jose M. Rodriguez , Lukas John C. , Calvo Rosario
Published: June 2003

Aims  To characterize the population pharmacokinetics of netilmicin, an aminoglycoside antibiotic, in adult urology patients and to develop a covariate model for improved dose titration.

Methods  Data from 62 adult patients (55 male, seven female), undergoing urological surgery and treated with netilmicin for short‐term prophylaxis, were evaluated retrospectively. The group had (median, range) ages 68, 31–92 years, weights 72, 43–106 kg and heights 167, 148–182 cm. No patient showed renal impairment before netilmicin treatment (serum creatinine ≤1.9 mg dl−1). Netilmicin (100 mg) was administered as a maximum of four successive intravenous infusions of 30 min, at 8‐h intervals. A total of five blood samples were collected from each patient. Prior to analysis, the dataset was divided into ‘index’ (n = 44) and ‘validation’ (n = 18) groups at random. The time courses of netilmicin concentrations from all subjects were analysed using a mixed effects, population, nonlinear modelling package (WinNonMix). For covariate model development, a stepwise procedure was used with backward elimination followed by forward inclusion based on age, sex, weight, height, creatinine clearance and type of surgery. The final covariate model parameters from the index group were used to simulate concentrations in the validation group and the bias and precision were compared with the observations.

Results  A bi‐compartmental open model with a proportional residual error best described the data. The population parameters for central and peripheral volumes of distribution were (typical population value [interindividual CV%]) Vc = 14.5 l [56%] and Vp = 10.2 l [not estimated], and the systemic and intercompartmental clearances were CL = 3.9 l h−1[42%] and CLQ = 10.1 l h−1[not estimated], respectively. The final population covariate relationships were based on sex (SEX) and creatinine clearance (CrCL): (Vc, l) = 18.9 − 5.9 × SEX [29%] and (CL, l h−1) = 0.06 × CrCL [33%]. Compared with the observations in the validation group, this model showed a bias (95% confidence interval) of −0.028 (−0.28, 0.25) and precision of 1.22 (0.78, 1.34).

Conclusion  Bi‐compartmental pharmacokinetic parameters of netilmicin have been estimated from clinical data in urological surgery patients using a population approach. A given single dose results in large variability in plasma concentrations and thus the population covariate final model can be used for direct estimation of initial dosing in patients.
Genotype and allele frequencies of TPMT, NAT2, GST, SULT1A1 and MDR‐1 in the Egyptian population
Authors: Hamdy Samar I. , Hiratsuka Masahiro , Narahara Kaori , Endo Naomi , El‐Enany Mervat , Moursi Nadia , Ahmed Mohammed S.‐E. , Mizugaki Michinao
Published: June 2003

Aims  The goal of this study was to determine the frequencies of important allelic variants in the TPMT, NAT2, GST, SULT1A1 and MDR‐1 genes in the Egyptian population and compare them with the frequencies in other ethnic populations.

Methods  Genotyping was carried out in a total of 200 unrelated Egyptian subjects. TPMT*2 was detected using an allele‐specific polymerase chain reaction (PCR) assay. TPMT*3C and NAT2 variants (*5,*6 and *7) were detected using an allele‐specific real‐time PCR assay. Detection of GSTM1 and GSTT1 null alleles was performed simultaneously using a multiplex PCR assay. Finally, a PCR‐restriction fragment length polymorphism assay was applied for the determination of TPMT*3A (*3B), SULT1A1*2 and MDR‐1 (3435T) variants.

Results  Genotyping of TPMT revealed frequencies of 0.003 and 0.013 for TPMT*3A and TPMT*3C, respectively. No TPMT*2 or *3B was detected in the analysed samples. The frequencies of specific NAT2 alleles were 0.215, 0.497, 0.260 and 0.028 for *4 (wild‐type), *5 (341C), *6 (590A) and *7 (857A), respectively. GSTM1 and GSTT1 null alleles were detected in 55.5% and 29.5% of the subjects, respectively. SULT1A1*2 was detected at a frequency of 0.135. Finally, the frequencies of the wild‐type allele (3435C) and the 3435T variant in the MDR‐1 gene were found to be 0.6 and 0.4, respectively.

Conclusions  We found that Egyptians resemble other Caucasians with regard to allelic frequencies of the tested variants of NAT2, GST and MDR‐1. By contrast, this Egyptian population more closely resemble Africans with respect to the TPMT*3C allele, and shows a distinctly different frequency with regard to the SULT1A1*2 variant. The predominance of the slow acetylator genotype in the present study (60.50%) could not confirm a previously reported higher frequency of the slow acetylator phenotype in Egyptians (92.00%), indicating the possibility of the presence of other mutations not detectable as T341C, G590A and G857A. The purpose of our future studies is to investigate for new polymorphisms, which could be relatively unique to the Egyptian population.
Effect of carbocysteine on cough reflex to capsaicin in asthmatic patients
Authors: Ishiura Yoshihisa , Fujimura Masaki , Yamamori Chihiro , Nobata Kouichi , Myou Shigeharu , Kurashima Kazuyoshi , Michishita Yasukatsu , Takegoshi Tadayoshi
Published: June 2003

Aims  Cough, one of the main symptoms of bronchial asthma, is a chronic airway inflammatory disease with functionally damaged bronchial epithelium. Recently, we established an animal model with cough hypersensitivity after antigen challenge and clearly showed the protective effect of carbocysteine in this model. This study was designed to investigate the clinical effect of carbocysteine for cough sensitivity in patients with bronchial asthma.

Methods  The effects of the two orally active mucoregulatory drugs, carbocysteine and ambroxol hydrochloride, on cough response to inhaled capsaicin were examined in 14 patients with stable asthma. Capsaicin cough threshold, defined as the lowest concentration of capsaicin eliciting five or more coughs, was measured as an index of airway cough sensitivity.

Results  Geometric mean values of the cough threshold at run‐in (baseline) and after 4 weeks’ treatment of placebo, 1500 mg day−1 of carbocysteine and 45 mg day−1 of ambroxol hydrochloride were 12.8 µM (95% confidence interval [CI] 5.5, 29.6), 11.0 µM (95% CI 4.4, 27.5), 21.0 µM (95% CI 8.8, 50.2) and 11.6 µM (95% CI 5.8, 23.3), respectively. The cough threshold for carbocysteine was significantly greater than those of ambroxol hydrochloride (P = 0.047) and placebo (P = 0.047), respectively.

Conclusions  These findings indicate that carbocysteine administration may be a novel therapeutic option for asthmatic patients, especially with cough variant asthma.
A novel metabolic pathway of morphine: formation of morphine glucosides in cancer patients
Authors: Chen X. Y. , Zhao L. M. , Zhong D. F.
Published: June 2003

Aims  To characterize directly the conjugated metabolites of morphine in urine samples of cancer patients.

Methods  Urine samples from the patients were treated by solid‐phase extraction method and chromatographed using three high‐performance liquid chromatography systems. Conjugated metabolites were directly detected with liquid chromatographic/ion trap mass spectrometric (LC/MSn) technique by selected ion monitoring, full scan MS/MS and MS3 modes.

Results  Six conjugated metabolites including two new metabolites M5 and M6 were found. Morphine‐3‐glucuronide (M‐3‐G) and morphine‐6‐glucuronide (M‐6‐G) were identified by comparing their l.c. retention times and multistage mass spectra with those of the reference substances. Two novel metabolites, morphine‐3‐glucoside and morphine‐6‐glucoside, as well as normorphine glucuronides were identified by comparing their mass fragment patterns and l.c. retention times with those of M‐3‐G and M‐6‐G. Hydrolysis of urine samples with β‐glucosidase and β‐glucuronidase provided further evidence of the metabolites M5 and M6 as morphine glucosides. The excretion amounts of morphine conjugates in urines were in the order of morphine glucuronides, morphine glucosides and normorphine glucuronides.

Conclusions  In the present study, the applications of l.c. separation and multistage mass spectra have permitted the direct identification of conjugated metabolites of morphine. To our knowledge, this is the first report about O‐linked glucosides of morphine at 3‐aromatic and 6‐aliphatic hydroxyl groups.
Central nervous system effects of moxonidine experimental sustained release formulation in patients with mild to moderate essential hypertension
Authors: Kemme Michiel J. B. , Post Jeroen P. vd , Schoemaker Rik C. , Straub Matthias , Cohen Adam F. , Van Gerven Joop M. A.
Published: June 2003

Objectives  The primary aim was to demonstrate that moxonidine, given in an experimental sustained release (SR) formulation, had no clinically relevant central nervous system (CNS) effects after 4 weeks of treatment. A clinically relevant CNS effect was predefined as more than 45° s−1 reduction in saccadic peak velocity (SPV), corresponding to the effects of one night's sleep deprivation.

Methods  In a randomized, double‐blind fashion, 35 patients with mild to moderate essential hypertension received placebo run‐in medication for 2 weeks, followed by 4 weeks’ moxonidine sustained release (1.5 mg o.d.) or placebo. On the first day and 1 and 4 weeks following the start of treatment, blood pressure was measured and CNS effects were assessed using SPV, visual analogue scales and EEG.

Results  On day 1 there was a significant, but not clinically relevant, reduction in the time‐corrected area under the effect curve (AUEC) for SPV in the moxonidine group compared with placebo [difference of 38° s−1; 95% confidence interval (CI) 23, 52]. This difference was no longer significant after one (9° s−1; 95% CI −17, 35) and 4 weeks (6.9° s−1; 95% CI −16, 30). Visual analogue scales for alertness showed similar results. A decrease in EEG α‐ and β‐power and an increase in δ‐power were only found on day 1 of moxonidine treatment. The AUEC for systolic/diastolic blood pressure relative to placebo was 23 (95% CI 17, 29)/13 (9, 16) mmHg lower on day 1 and remained reduced by 20 (11, 30)/12 (6, 17) and 15 (6, 25)/9 (3, 15) mmHg after 1 and 4 weeks’ moxonidine treatment.

Conclusions  Four weeks’ treatment with an experimental SR formulation resulted in tolerance to CNS effects (equivalence to placebo) while blood pressure‐lowering effects remained adequate. The tolerance to CNS effects was already observed after 1 week of treatment.
Penetration of piperacillin and tazobactam into pneumonic human lung tissue measured by in vivo microdialysis
Authors: Tomaselli Florian , Dittrich Peter , Maier Alfred , Woltsche Michael , Matzi Veronika , Pinter Johannes , Nuhsbaumer Stephan , Pinter Hans , Smolle Josef , Smolle‐Jüttner Freyja M.
Published: June 2003

Objectives  The pharmacokinetic profile of antibiotics at the site of anti‐infective action is one of the most important determinants of drug response, since it correlates with antimicrobial effect. Up to now, only limited information on the lung tissue pharmacokinetics of antibiotic agents has been available. The aim of this study was to measure, using a new microdialysis‐based approach, antibiotic penetration into the extracellular space fluid of pneumonic human lung parenchyma.

Patients and methods  The lung penetration of a combination of piperacillin and tazobactam, substances with low protein binding, was determined in five patients suffering from pneumonia and metapneumonic pleural empyema. The condition was treated by decortication after lateral thoracotomy. Intra‐, or post‐operatively, respectively, two microdialysis probes were inserted into pneumonic lung tissue, and into healthy skeletal muscle to obtain reference values. Serum and microdialysis samples were collected at 20‐min intervals for at last 8 h following i.v. administration of a single dose of 4 g piperacillin and 500 mg tazobactam.

Results  The mean free interstitial concentration profiles of piperacillin in infected lung tissue and serum showed a maximal tissue concentration (Cmax) of 176.0 ± 105.0 mg l−1 and 326.0 ± 60.6 mg l−1, respectively. The mean AUC (area under the curve) for infected lung tissue was 288.0 ± 167.0 mg.h l−1 and for serum 470.0 ± 142.0 mg.h l−1. There was a statistically significant difference between AUC (lung) and AUC (serum) (P = 0.018) as well as between AUC (lung) and AUC (muscle) (P = 0.043). The intrapulmonary concentrations of piperacillin and tazobactam exceeded the minimum inhibitory concentrations (MIC) for most relevant bacteria for 4–6 h. The procedure was well tolerated by all patients and no adverse events or microdialysis‐associated side‐effects were observed.

Conclusion  This microdialysis technique enabled continuous tissue pharmacokinetic measurement of free, unbound anti‐infective agents in the lung tissue of patients with pneumonia. The present data corroborate the use of piperacillin and tazobactam in the treatment of lung infections caused by extracellular bacteria and demonstrate the distribution of piperacillin and tazobactam in the interstitial space of pneumonic lung tissue.
CYP3A5 phenotype‐genotype correlations in a British population
Authors: King Barry P. , Leathart Julian B. S. , Mutch Elaine , Williams Faith M. , Daly Ann K.
Published: June 2003

Aims  To develop a polymerase chain reaction (PCR)‐restriction fragment length polymorphism (RFLP)‐based assay to genotype for hepatic CYP3A5 expression and to use this assay to study a British population.

Methods  CYP3A5‐specific PCR primers were designed with one including a base‐pair mismatch to create a RsaI site in samples positive for A6986 (CYP3A5*1 allele). Following PCR and RsaI digestion, different band patterns on electrophoresis were predicted for individuals positive for CYP3A5 (CYP3A5*1 allele) compared with those who do not express the gene (CYP3A5*3 homozygotes). The assay was validated by DNA sequencing. DNA samples from a human liver bank consisting of 22 livers whose CYP3A5 expression had been determined by immunoblotting and a group of random individuals (n = 100) from the North‐east of England were genotyped by the new assay.

Results  In the liver bank, five out of 22 samples expressed CYP3A5 at significant levels (>20 pmol mg−1 protein) and were found to have the genotype CYP3A5*1/CYP3A5*3 by the PCR‐RFLP assay. All other liver DNA samples were CYP3A5*3 homozygotes. In the group of 100 random individuals, 13 had the genotype CYP3A5*1/CYP3A5*3 and all others were CYP3A5*3 homozygotes, predicting that 13% (95% confidence interval (CI) 6%, 20%) would show significant hepatic CYP3A5 expression. The frequency for the CYP3A5*1 allele was 0.065 (95% CI 0.032, 0.097).

Conclusions  We have developed a simple assay for the detection of the CYP3A5*1/CYP3A5*3 alleles and shown that in a British population their frequency is similar to that reported previously. We have also shown a good correlation between hepatic CYP3A5 expression and genotype for a British Caucasian liver bank.