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N Lowe

Publications and source records attributed to N Lowe.

At least 19 recordsLinked to original sources
PubMed2006

The analysis of 51 genes in DSM-IV combined type attention deficit hyperactivity disorder: association signals in DRD4, DAT1 and 16 other genes.

Attention deficit hyperactivity disorder (ADHD) is a common neurodevelopmental disorder, starting in early childhood and persisting into adulthood in the majority of cases. Family and twin studies have demonstrated the importance of genetic factors and candidate gene association studies have identified several loci that exert small but significant effects on ADHD. To provide further clarification of reported associations and identify novel associated genes, we examined 1,038 single-nucleotide polymorphisms (SNPs) spanning 51 candidate genes involved in the regulation of neurotransmitter pathways, particularly dopamine, norepinephrine and serotonin pathways, in addition to circadian rhythm genes. Analysis used within family tests of association in a sample of 776 DSM-IV ADHD combined type cases ascertained for the International Multi-centre ADHD Gene project. We found nominal significance with one or more SNPs in 18 genes, including the two most replicated findings in the literature: DRD4 and DAT1. Gene-wide tests, adjusted for the number of SNPs analysed in each gene, identified associations with TPH2, ARRB2, SYP, DAT1, ADRB2, HES1, MAOA and PNMT. Further studies will be needed to confirm or refute the observed associations and their generalisability to other samples.

Adolescent↗
PubMed2005

Association of the paternally transmitted copy of common Valine allele of the Val66Met polymorphism of the brain-derived neurotrophic factor (BDNF) gene with susceptibility to ADHD.

Attention deficit hyperactivity disorder (ADHD) is a common, highly heritable, neurodevelopmental disorder with onset in early childhood. Genes involved in neuronal development and growth are, thus, important etiological candidates and brain-derived neurotrophic factor (BDNF), has been hypothesized to play a role in the pathogenesis of ADHD. BDNF is a member of the neurotrophin family and is involved in the survival and differentiation of dopaminergic neurons in the developing brain (of relevance because drugs that block the dopamine transporter can be effective therapeutically). The common Val66Met functional polymorphism in the human BDNF gene (rs 6265) was genotyped in a collaborative family-based sample of 341 white UK or Irish ADHD probands and their parents. We found evidence for preferential transmission of the valine (G) allele of BDNF (odds ratio, OR=1.6, P=0.02) with a strong paternal effect (paternal transmissions: OR=3.2, P=0.0005; maternal transmissions: OR=1.00; P=1.00). Our findings support the hypothesis that BDNF is involved in the pathogenesis of ADHD. The transmission difference between parents raises the possibility that an epigenetic process may be involved.

Amino Acid Substitution↗
PubMed2005

Tryptophan hydroxylase 2 (TPH2) gene variants associated with ADHD.

Genetic and pharmacological studies have emphasised the role of serotonin 5-hydroxytryptamine (5-HT) as a possible etiologic factor in the development of attention-deficit hyperactivity disorder (ADHD). Tryptophan hydroxylase (TPH) is a rate-limiting enzyme in the biosynthesis of serotonin from tryptophan. Originally, the TPH gene was thought to be widely expressed, but a second form of TPH, TPH2, was recently identified and the TPH2 gene was found to be solely expressed in the brain. We examined eight single nucleotide polymorphisms (SNP) in the TPH2 gene for association with ADHD in 179 Irish nuclear families. Transmission disequilibrium test analysis revealed significant association between the T allele of marker rs1843809 with the disorder (chi2=12.2, P=0.0006, OR=2.36). Stratifying data by the sex of the transmitting parent showed that this association was enhanced when paternal transmission was considered (OR=3.7). In addition, several haplotypes (all including the associated marker) were associated with ADHD. These preliminary findings suggest that TPH2 is a susceptibility locus for ADHD. Further confirmation, preferably from different ethnic groups, is required to firmly implicate TPH2 in the pathophysiology of ADHD.

Attention Deficit Disorder with Hyperactivity↗
PubMed2004

Fluocinolone acetonide topical oil for scalp psoriasis.

Numerous preparations that are available for the treatment of psoriasis of the scalp contain high potency steroids, such as betamethasone dipropionate lotion or clobetasol propionate solution. Of special interest is a currently marketed oil preparation that contains the steroid fluocinolone acetonide (0.01%), classified as low potency (Class 6) steroid. Because the combination of emollients in the vehicle base are present to aid in softening the stratum corneum and allow penetration of the steroid component into the lower skin layer, it was thought this preparation would be an efficient treatment for psoriasis of the scalp. This study was designed to demonstrate the efficacy, tolerance and safety of fluocinolone acetonide 0.01% in oil, compared to its vehicle, for the treatment of scalp psoriasis. This was a randomized, double-blind, vehicle-controlled multi-center study in patients with moderate to severe scalp psoriasis. At the completion of the treatment period (21 days) all signs of psoriasis had improved in both treatment groups, the improvements in the FA group being significantly greater compared to those in the vehicle-treated group. The results of the physician global assessments of improvement in the signs of psoriasis from baseline confirmed the findings. Significantly more patients in the FA group had a good or better improvement from baseline compared to the number in the vehicle-treated group. The results of this study conclusively show that FA in an oil base that aids in the softening of the skin and allows penetration of the steroid into the stratum corneum, is an effective treatment for psoriasis of the scalp. This study also showed that the vehicle alone causes an improvement in the signs of psoriasis, but that the addition of 0.1% of the low potency steroid, fluocinolone acetonide, leads to a significantly better improvement.

Administration, Topical↗
PubMed2004

The place of botulinum toxin type A in the treatment of focal hyperhidrosis.

BACKGROUND: Hyperhidrosis (primary or secondary) is excessive sweating beyond that required to return body temperature to normal. It can be localized or generalized, commonly affecting the axillae, palms, soles or face, and can have a substantial negative effect on a patient's quality of life. IMPACT OF DISEASE: Objective evaluation comprising quantitative assessment (gravimetric and Minor's iodine starch test) and subjective evaluation (Dermatology Quality of Life Index and Hyperhidrosis Impact Questionnaire) allow accurate assessment of the impact of hyperhidrosis on patients. BOTULINUM TOXIN TYPE A: Botulinum toxin type A acts by inhibiting the release of acetylcholine at the presynaptic membrane of cholinergic neurones. It has proved useful in treating a number of diseases relating to muscular dystonia and is now proving beneficial in treating hyperhidrosis. Clinical trials investigating botulinum toxin type A use in axillary and palmar hyperhidrosis show significant benefits with few side-effects reported, with a favourable impact also being seen on patient quality of life. Botulinum toxin type A injections are generally well-tolerated with beneficial results lasting from 4 to 16 months. CONCLUSIONS: Botulinum toxin type A injections are an effective and well-tolerated treatment for hyperhidrosis. This paper proposes a positioning of this treatment along with current established treatments, and highlights the role of botulinum toxin type A as a valuable therapy for the treatment of hyperhidrosis.

Axilla↗
PubMed2004

Sustainable biosolids--welcomed practice through community partnership and the consequential economic benefits.

Technically, most people agree that conserving soil organic matter and completing nutrient cycles by applying animal manures, treated organic wastes and biosolids to land is the most sustainable option in the majority of situations. It is also generally the least expensive. There has been a huge amount of research into the hazards, and this has concluded that the risks can be managed to acceptable levels. But there has been insufficient attention to communicating this knowledge, as so often in the scientific and technological arena. Perception is reality. Nowadays compliance with regulations (whilst essential) is not enough; public and stakeholder attitudes can be of decisive importance. Sometimes policy-makers speculate what public attitudes might be without really asking them. This paper will describe an initiative to create a partnership open to anybody with an interest in the use of organic materials on land to develop consensus on good practice and to share knowledge. It summarises an attitude survey of more than 140 organisations, which was then debated at a workshop in July 2002. The conclusion from this study was that all parties considered a partnership is essential to share knowledge, build mutual trust and agree practices that are welcomed by all in the food chain. The paper will describe the steps to establishing a partnership organisation, its aims and objectives, the work to date and the plans for the future. The Environment Agency considers this very important and has largely funded the work to date. The consequences of failing to establish welcomed practices would be loss of the facility to use organic resources on land.

Conservation of Natural Resources↗
PubMed2003

Linkage disequilibrium mapping at DAT1, DRD5 and DBH narrows the search for ADHD susceptibility alleles at these loci.

Abnormalities in dopaminergic neurotransmission are now accepted as factors in predisposing to ADHD. Evidence of associations between dopamine transporter gene polymorphism and ADHD was first reported by Cook et al. We confirmed the DAT1 association and also identified two additional susceptibility loci at the DRD5 and DBH. Notably, none of the associated variants at these three genes are known to be expressed. Other variants within or closely mapped to the associated alleles are likely to be relevant. In this investigation, we analyse additional markers creating a high-density map across and flanking these genes, and measure intermarker linkage disequilibrium (LD). None of the newly examined markers were more strongly associated with ADHD. At DAT1, the pattern of intermarker LD and haplotype association with the phenotype between exon 9 and the 3' of the gene suggests that the functional variant at DAT1 may be located to this region. For DRD5, three markers, covering a region of approximately 68 kb including the single DRD5 exon are all associated with disease, and thus do not provide localizing information. However, the data for DBH point to a region close to the centre of the gene. Correlation between D' and physical distance was observed between markers at DAT1 and DRD5 for distances less than 50 kb. This was not the case for DBH, where LD breakdown was observed between the intron 5 and intron 9 polymorphisms although they are only 9 kb apart. Further genetic analysis is unlikely to refine the location of susceptibility variants and functional assessment of variants within associated regions is required.

Adolescent↗
PubMed2002

Evidence that variation at the serotonin transporter gene influences susceptibility to attention deficit hyperactivity disorder (ADHD): analysis and pooled analysis.

Reduced central serotonergic activity has been implicated in poor impulse regulation and aggressive behaviour in animals, adults and also young children.(1,2) Two recently published studies have implicated variation at a polymorphism in the promoter of the serotonin transporter (5HTT; hSERT) in influencing susceptibility to ADHD.(3,4) Consistent with these results we have also found a trend for the long allele of the promoter polymorphism to influence susceptibility to ADHD in a sample of 113 ADHD parent proband trios (65 transmissions vs 49 non-transmissions, chi(2) = 2.25, P = 0.13). A pooled analysis of our, and these published results demonstrated a significant over representation of the long allele of the promoter in ADHD probands compared to controls (chi(2) = 7.14, P = 0.008). We have also examined two other 5HTT polymorphisms (the VNTR in intron 2 and the 3' UTR SNP). TDT analysis demonstrated preferential transmission of the T allele of the 3' UTR SNP (chi(2) = 4.06, P = 0.04). In addition, ETDT analysis of haplotypes demonstrated significant preferential transmission of haplotypes containing the T allele of the 3' UTR SNP with the long allele of the promoter polymorphism (chi(2) = 13.18, 3 df, P = 0.004) and the 10 repeat of the VNTR (chi(2) = 8.77, 3 df, P = 0.03). This study provides further evidence for the possible involvement of the serotonin transporter in susceptibility to ADHD.

Adult↗
PubMed2001

Tramtrack69 interacts with the dMi-2 subunit of the Drosophila NuRD chromatin remodelling complex.

dMi-2, the ATPase subunit of the Drosophila nucleosome remodelling and histone deacetylation (dNuRD) complex, was identified in a two-hybrid screen as an interacting partner of the transcriptional repressor, Tramtrack69 (Ttk69). A short region of Ttk69 is sufficient to mediate this interaction. Ttk69, but not the Ttk88 isoform, co-purifies with the dNuRD complex isolated from embryo extracts. dMi-2 and Ttk69 co-immunoprecipitate from embryonic extracts, indicating that they can associate in vivo. Both dMi-2 and Ttk69 co-localize at a number of discrete sites on polytene chromosomes, showing that they bind common target loci. We also demonstrate that dMi-2 and Ttk interact genetically, indicating a functional interaction in vivo. We propose that Ttk69 represses some target genes by remodelling chromatin structure through the recruitment of the dNuRD complex.

Adenosine Triphosphatases↗
PubMed2001

Comparison of treatment of acne vulgaris with alternate-day applications of tazarotene 0.1% gel and once-daily applications of adapalene 0.1% gel: a randomized trial.

Tazarotene and adapalene are recently introduced topical retinoids that are useful in the treatment of acne vulgaris. The clinical benefits of each drug have now been compared in a multicenter, double-blind, randomized, parallel-group study involving 164 patients with mild-to-moderate facial acne vulgaris. Patients were randomized to receive 15 weeks' treatment with alternate-day tazarotene 0.1% gel, with vehicle gel on the intervening evenings, or once-daily adapalene 0.1% gel. Both regimens were comparably effective with no significant between-group differences in efficacy measures. A total of 74% of tazarotene-treated subjects and 73% of adapalene-treated subjects achieved at least a 50% improvement in their acne. In addition, there were no clinically significant differences in tolerability. It is concluded that an alternate-day tazarotene regimen offers efficacy and thus tazarotene treatment can be useful even in patients whose compliance may be suboptimal. An alternate-day regimen also offers the potential for considerable savings in drug costs.

Acne Vulgaris↗
PubMed2000

The structural basis for the recognition of acetylated histone H4 by the bromodomain of histone acetyltransferase gcn5p.

The bromodomain is an approximately 110 amino acid module found in histone acetyltransferases and the ATPase component of certain nucleosome remodelling complexes. We report the crystal structure at 1.9 A resolution of the Saccharomyces cerevisiae Gcn5p bromodomain complexed with a peptide corresponding to residues 15-29 of histone H4 acetylated at the zeta-N of lysine 16. We show that this bromodomain preferentially binds to peptides containing an N:-acetyl lysine residue. Only residues 16-19 of the acetylated peptide interact with the bromodomain. The primary interaction is the N:-acetyl lysine binding in a cleft with the specificity provided by the interaction of the amide nitrogen of a conserved asparagine with the oxygen of the acetyl carbonyl group. A network of water-mediated H-bonds with protein main chain carbonyl groups at the base of the cleft contributes to the binding. Additional side chain binding occurs on a shallow depression that is hydrophobic at one end and can accommodate charge interactions at the other. These findings suggest that the Gcn5p bromodomain may discriminate between different acetylated lysine residues depending on the context in which they are displayed.

Acetylation↗
PubMed2000

Two considerations for patients with psoriasis and their clinicians: what defines mild, moderate, and severe psoriasis? What constitutes a clinically significant improvement when treating psoriasis?

The definitions of psoriasis severity and clinically significant improvement in psoriasis are used to classify treatments, obtain Food and Drug Administration approval, and determine product labeling and reimbursement. The Medical Advisory Board of the National Psoriasis Foundation has addressed these issues because of their importance in the clinical trials that are conducted to gain FDA approval of indications. Narrow indications, which are without a sound rational basis, will-in this era of constant oversight by third party payers-affect physicians' ability to manage patients with psoriasis. Body surface area (BSA) is usually used to define severity for clinical trials. It is not optimal for defining psoriasis severity because there are some patients with low BSA involvement who have very severe psoriasis and some patients with high BSA involvement who have mild psoriasis. We conclude that a quality of life (QOL) standard is better than BSA measurement for identifying patients with severe psoriasis. The second issue is what defines clinically significant improvement for patients with psoriasis. Setting an arbitrarily high criterion of clinical efficacy for new psoriasis treatments will likely limit the development and approval of useful treatments. To maximize the availability of useful psoriasis treatments, it is our thesis that psoriasis treatments should be approved when they have been shown to produce a statistically significant level of improvement in well-designed clinical trials.

Humans↗
PubMed1999

The recognition of distorted DNA structures by HMG-D: a footprinting and molecular modelling study.

The high mobility group (HMG) domain is a DNA binding motif found in some eukaryotic chromosomal proteins and transcription factors. This domain binds in the minor groove of DNA inducing a sharp bend and also preferentially binds to certain distorted DNA structures. Although structures of sequence-specific HMG domains with their cognate double-helical DNA binding sites have been solved, the nature of the interaction of the domain with distorted DNA remains to be established. In this study we have investigated the interaction of HMG-D, a Drosophila counterpart of the vertebrate HMG1, with a DNA oligomer containing a bulge of two adenine residues. We show by footprinting that HMG-D binds preferentially on one side of the bulged DNA. Based on these data and on the published NMR structures of the HMG domain of HMG-D and the LEF-1-DNA complex, we modelled the HMG-D - bulged DNA complex. This model predicts that two residues, Val32 and Thr33, in the loop between alpha-helices I and II are inserted deep into the "hole" in the DNA formed by the two missing bases on one strand of the DNA bulge. Mutation of these residues confirmed that both are required for the efficient binding and bending of DNA by HMG-D. We discuss both the role of this loop in the recognition of distorted DNA structures by non-sequence specific HMG domain proteins and that of the basic tail in stabilising the induced DNA bend.

Amino Acid Sequence↗
PubMed1999

The effects of finasteride on scalp skin and serum androgen levels in men with androgenetic alopecia.

BACKGROUND: Data suggest that androgenetic alopecia is a process dependent on dihydrotestosterone (DHT) and type 2 5alpha-reductase. Finasteride is a type 2 5alpha-reductase inhibitor that has been shown to slow further hair loss and improve hair growth in men with androgenetic alopecia. OBJECTIVE: We attempted to determine the effect of finasteride on scalp skin and serum androgens. METHODS: Men with androgenetic alopecia (N = 249) underwent scalp biopsies before and after receiving 0.01, 0.05, 0.2, 1, or 5 mg daily of finasteride or placebo for 42 days. RESULTS: Scalp skin DHT levels declined significantly by 13.0% with placebo and by 14.9%, 61.6%, 56. 5%, 64.1%, and 69.4% with 0.01, 0.05, 0.2, 1, and 5 mg doses of finasteride, respectively. Serum DHT levels declined significantly (P <.001) by 49.5%, 68.6%, 71.4%, and 72.2% in the 0.05, 0.2, 1, and 5 mg finasteride treatment groups, respectively. CONCLUSION: In this study, doses of finasteride as low as 0.2 mg per day maximally decreased both scalp skin and serum DHT levels. These data support the rationale used to conduct clinical trials in men with male pattern hair loss at doses of finasteride between 0.2 and 5 mg.

5-alpha Reductase Inhibitors↗
PubMed1999

Clinical dose ranging studies with finasteride, a type 2 5alpha-reductase inhibitor, in men with male pattern hair loss.

BACKGROUND: Androgenetic alopecia is a common condition of adult men. Finasteride, a type 2 5alpha-reductase inhibitor, decreases the formation of dihydrotestosterone from testosterone. OBJECTIVE: Two separate clinical studies were conducted to establish the optimal dose of finasteride in men with this condition. METHODS: Men from 18 to 36 years of age with moderate vertex male pattern hair loss received finasteride 5, 1, 0.2, or 0.01 mg/day or placebo based on random assignment. Efficacy was determined by scalp hair counts, patient self-assessment, investigator assessment, and assessment of clinical photographs. Safety was assessed by clinical and laboratory measurements and by analysis of adverse experiences. RESULTS: Efficacy was demonstrated for all end points for finasteride at doses of 0.2 mg/day or higher, with 1 and 5 mg demonstrating similar efficacy that was superior to lower doses. Efficacy of the 0.01 mg dose was similar to placebo. No significant safety issues were identified in the trials. CONCLUSION: Finasteride 1 mg/day is the optimal dose for the treatment of men with male pattern hair loss and was subsequently identified for further clinical development.

5-alpha Reductase Inhibitors↗
PubMed1999

Effects of acitretin on the liver.

BACKGROUND: Therapy with aromatic retinoids for psoriasis is associated with abnormal liver function test findings and toxic hepatitis (in 1.5% of patients). OBJECTIVE: Our purpose was to determine the safety of acitretin with respect to liver function, on the basis of biopsy. METHODS: We treated 128 adults (with chronic, stable psoriasis) with oral acitretin (25-75 mg/day) for four 6-month intervals in a prospective, open-label, 2-year multicenter study. Liver biopsies were performed before and after study completion (2 years). RESULTS: Eighty-three available pairs of pretreatment and posttreatment liver biopsies demonstrated no change in 49 patients (59%), improvement in 20 (24%), and worsening in 14 (17%). Of these 14 patients with decrements in biopsy status, most changes were mild. There was no correlation between liver function test abnormalities or cumulative acitretin dose and changes in liver biopsy status. CONCLUSION: Acitretin therapy elicited no biopsy-proven hepatotoxicity in this prospective 2-year study. These findings suggest that periodic liver biopsy may not be necessary with acitretin treatment.

Acitretin↗
PubMed1998

Quality of life in patients with bioprostheses and mechanical prostheses. Evaluation of cohorts of patients aged 51 to 65 years at implantation.

BACKGROUND: The purpose of this study was 3-fold: to compare the quality of life (QOL) in age- and sex-matched patients who received biological and mechanical prosthetic valves in isolated aortic valve replacement, to compare the QOL of patients with aortic valve replacement with the general population, and to compare patients with biological and mechanical prostheses with certain valve-specific questions and relate these responses to overall QOL. METHODS AND RESULTS: Patient-perceived QOL was evaluated in 200 patients who were sampled from a population of 420 patients (age range 51 to 65 years) who underwent isolated aortic valve replacement in the period of 1986 to 1996. One hundred of the sampled patients had a mechanical valve inserted and an equal number had porcine bioprostheses. Three survey instruments were used to examine perceived QOL: the SF-12 form, a 7-valve specific question form, and the Lamy Smiley Faces form. The response to the questionnaires was 89.5% (179 patients). Patients with mechanical valves were more bothered by valve sounds (P < 0.01) and had a negative correlation (P < 0.01) between valve sound and QOL on the mental scale only. Patients with biological valves were more fearful of the need for reoperation (P < 0.01), but there was no correlation between fear and QOL. The mechanical valve group had a negative correlation (P < 0.01) between fear of reoperation and QOL on both the mental and physical scales. There was no difference between the 2 cohorts with respect to fear of valve failure. Patients with mechanical valves were more concerned about frequency of medical visits and blood tests (P < 0.01) as well as the possibility of anticoagulant-related bleeding events (P < 0.01). QOL was equivalent between the 2 groups and to the general population for the same age group. Ninety-seven percent of the patients indicated they would make the same surgical decision again with regard to valve replacement; there was no difference between the 2 valve groups on this question. CONCLUSIONS: Patient-perceived QOL is similar between patients with aortic mechanical and biological valve replacement in the studied age group and comparable to the general population of similar age. Although certain valve-specific differences exist between the 2 prosthetic types, these differences do not appear to affect overall QOL as described by these patients.

Aged↗