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C Thompson

Publications and source records attributed to C Thompson.

At least 73 records · Page 4Linked to original sources
PubMed2000

Compliance with antidepressant medication in the treatment of major depressive disorder in primary care: a randomized comparison of fluoxetine and a tricyclic antidepressant.

OBJECTIVE: Many claims have been made for superior compliance with selective serotonin reuptake inhibitors (SSRIs) compared with tricyclic antidepressants, but to date meta-analyses have not confirmed reduced dropouts in randomized controlled trials. The authors used a randomized study design to evaluate differential compliance with antidepressant medications in a primary care setting. METHOD: A total of 152 patients treated in 10 primary care practices in the United Kingdom were included in a randomized, open-label, parallel-group study of fluoxetine and dothiepin at therapeutic doses for 12 weeks. Compliance was assessed by using pill count, patient questionnaires, and the Medication Event Monitoring System. RESULTS: The level of compliance with fluoxetine was numerically higher than the level of compliance with dothiepin on all three primary outcome measures, although the differences were not significant. In a secondary analysis using data from the Medication Event Monitoring System, both a survival analysis for length of time without a gap in medicine taking and a derived compliance index showed a significant advantage to fluoxetine. Patients in the fluoxetine group reported superior response on the health transition scale of the 36-item Short-Form Health Survey Questionnaire and numerically greater improvement on the Hamilton Depression Rating Scale. In both treatment arms patients with a superior compliance index were more likely to have improved in Hamilton depression scale scores by the last study visit. CONCLUSIONS: This study supports recent meta-analyses of SSRIs versus tricyclic antidepressants in finding no significant differences in crude indices of compliance between fluoxetine and dothiepin, despite marked differences in side effect profile and dose regimen. However, both a survival analysis and a new measure that takes account of prolonged periods of noncompliance distinguished between the treatments and was associated with improvement in both groups.

Adolescent↗
PubMed2000

Genital herpes simplex typing in genitourinary medicine: 1995-1999.

Retrospective study of all culture-positive first episode genital herpes (HSV) presenting to genitourinary medicine (GUM) over a 4-year period, showing a high prevalence of type 1 (71%) HSV infection, most marked in women. This has implications for counselling patients and for the use of type-specific serological testing.

Adult↗
PubMed2000

Profile of epidermal growth factor receptor (EGFr) expression in human malignancies: effects of exposure to EGF and its biological influence on established human tumour cell lines.

The aim of this study was to compare the profile of EGFr expression in transitional cell carcinoma of the bladder (TCC) and in oral squamous cell carcinoma (OSCC). In addition, to study the influence of EGF stimulation on the expression of major histocompatibility complex class I antigens, placental alkaline phosphatase (PLAP) as well as changes in tumour cell sensitivity to cisplatin using immunocytochemical staining, a colorimetric assay and SDS-gel electrophoresis. The results showed that: a) strong EGFr expression could be seen in 22/88 (27%) cases of TCCs. In oral tumours the values for non-invasive ameloblastoma and invasive OSCC were 4/25 (16%) and 30/41 (73%) respectively. b) EGFr expression in tumour cell lines paralleled that of tumour biopsies. The number of lines expressing high and low EGFr expression amongst TCCs were 4 and 4 and in OSCCs were 3 and 1 respectively. c) Exposure of tumour cell lines to EGF led to: i) an increase in EGFr expression (stimulatory indices SI, ranged from 1.06 to 2.58) for TCCs but a decrease in the case of OSCCs (SI ranged from 0.01 to 0.85). The corresponding SI values for class I antigens were 0.95-1.16 and 0.10-0.84. ii) A significant reduction in expression of PLAP by OSCC cell lines. iii) An increased susceptibility of OSCC cell lines to cisplatin by as much as 14% (p<0.001). These data demonstrated the overexpression of EGFr in a significant proportion of TCCs. As for oral tumours it depended on whether they were of an invasive or non-invasive type. In the invasive cases the majority overexpressed EGFr. The exposure of OSCC but not TCC tumour cells to EGF resulted in down regulation of EGFr and class I antigens. The expression of PLAP was also significantly reduced. Exposure of OSCC cells to EGF resulted in their increased susceptibility to cisplatin. The data supports the notion that the mitogenic activation of some tumour cells by EGF resulted in a reduction of their immune visibility, differentiation status and an increase in chemosensitivity.

Alkaline Phosphatase↗
PubMed2000

Effect of climate and type of storage container on aflatoxin production in corn and its associated risks to wildlife species.

The effects of grain storage containers on aflatoxin production, and the relationship between the level of aflatoxin and the number and weight of fluorescing kernels were determined in corn (Zea maize) stored in controlled climate regimes. Two hundred and forty 100-g samples were held up to 3 mos using four types of storage containers placed in four climates. Storage containers included corn placed in metal cans, paper bags, plastic bags, and paper bags placed in plastic bags. Climates were constant during the duration of the project and included a combination of temperatures and humidities. Temperatures were 29-32 C and 14-18 C; relative humidities were 85-88% and 35-40%. In addition, corn was exposed to environmental conditions conductive for aflatoxin production and 100 g samples were randomly collected, examined under ultraviolet light for fluorescence, and then quantified for aflatoxin levels. Corn samples tested negative for aflatoxin at the beginning of the project. Main (i.e., container, climate, and month) and interactive effects were not observed. Mean levels of aflatoxin ranged from 0 to 151 microg/kg. Aflatoxin was produced regardless of type of storage container, time of storage, and climatic conditions; however, only 8% of the samples produced aflatoxin levels that exceeded 50 microg/kg. Fluorescing corn ranged from 0 to 19 kernels per sample, while aflatoxin levels ranged from 0 to 1,375 microg/kg for the same samples. No relationships were found between the number and weight of fluorescing kernels of corn and aflatoxin levels. The black light test yielded a false negative rate of 23% when in fact the aflatoxin concentrations exceeded 50 microg/kg. Therefore, quantifying fluorescing grain under UV light should not be considered a feasible alternative for aflatoxin testing of grain intended for wildlife.

Aflatoxins↗
PubMed1999

Mutational analysis of avidity and fine specificity of anti-levan antibodies.

Using the polyfructose, bacterial levan, as a model polysaccharide, we analyzed how V regions affect binding in anti-polysaccharide mAbs. Previously, panels of mAb were constructed from bacterial levan-immunized BALB/c and CBA/Ca mice. The BALB/c mAb were mostly germline VHJ606:Vkappa11, and a subset contained presumed somatic mutations in the complementarity-determining regions (CDRs) that correlated with increases in avidity for the beta(2-->1) inulin linkage of levan. The CBA/Ca mAb were more heterogeneous in V gene usage, but a subset of inulin-nonreactive mAb were VHJ606:Vlambda and had VH sequence differences in the CDRs from the VHJ606 regions of the BALB/c mAb. In this report, VHJ606 Abs containing various combinations of specifically mutated H and L chains were produced by engineered transfectants and tested for inulin avidity and levan binding. Two presumed somatic mutations seen in CDRs of the BALB/c hybridomas were shown to directly cause marked increases in avidity for inulin (VH N53H, 9-fold; VL N53I, 20-fold; together, 46-fold) but not for beta(2-->6) levan. Exchange of either positions 50 or 53 in VH or the H3 loop between the BALB/c and CBA/Ca mAb resulted in either fine specificity shift or total loss of bacterial levan binding. Three-dimensional models of the V regions suggested that residues that affect binding to inulin alone are near the edge of the CDR surface, while residues involved with binding both forms of levan and affecting fine specificity are in the VH:VL junctional area.

Amino Acid Sequence↗
PubMed1999

Hard Burst Emission from the Soft Gamma Repeater SGR 1900+14.

We present evidence for burst emission from SGR 1900+14 with a power-law high-energy spectrum extending beyond 500 keV. Unlike previous detections of high-energy photons during bursts from soft gamma repeaters (SGRs), these emissions are not associated with extraordinarily bright flares. Not only is the emission hard, but the spectra are better fitted by D. Band's gamma-ray burst (GRB) function rather than by the traditional optically thin thermal bremsstrahlung model. We find that the spectral evolution within these hard events obeys a hardness/intensity anticorrelation. Temporally, these events are distinct from typical SGR burst emissions in that they are longer ( approximately 1 s) and have relatively smooth profiles. Despite a difference in peak luminosity of greater, similar1011 between these bursts from SGR 1900+14 and cosmological GRBs, there are striking temporal and spectral similarities between the two kinds of bursts, aside from spectral evolution. We outline an interpretation of these events in the context of the magnetar model.

Journal Article↗
PubMed1999

Statistical Properties of SGR 1900+14 Bursts.

We study the statistics of soft gamma repeater (SGR) bursts using a database of 187 events detected with BATSE and 837 events detected with the Rossi X-Ray Timing Explorer Proportional Counter Array; all events are from SGR 1900+14 during its 1998-1999 active phase. We find that the fluence or energy distribution of bursts is consistent with a power law of index 1.66, over 4 orders of magnitude. This scale-free distribution resembles the Gutenberg-Richter law for earthquakes and gives evidence for self-organized criticality in SGRs. The distribution of time intervals between successive bursts from SGR 1900+14 is consistent with a lognormal distribution. There is no correlation between burst intensity and the waiting times till the next burst, but there is some evidence for a correlation between burst intensity and the time elapsed since the previous burst. We also find a correlation between the duration and the energy of the bursts, but with significant scatter. In all these statistical properties, SGR bursts resemble earthquakes and solar flares more closely than they resemble any known accretion-powered or nuclear-powered phenomena. Thus, our analysis lends support to the hypothesis that the energy source for SGR bursts is internal to the neutron star and plausibly magnetic.

Journal Article↗
PubMed1999

Robots.

Explore the source record for details and available documents.

Gait↗
PubMed1999

Differential regulation of mammalian period genes and circadian rhythmicity by cryptochromes 1 and 2.

Cryptochromes regulate the circadian clock in animals and plants. Humans and mice have two cryptochrome (Cry) genes. A previous study showed that mice lacking the Cry2 gene had reduced sensitivity to acute light induction of the circadian gene mPer1 in the suprachiasmatic nucleus (SCN) and had an intrinsic period 1 hr longer than normal. In this study, Cry1(-/-) and Cry1(-/-)Cry2(-/-) mice were generated and their circadian clocks were analyzed at behavioral and molecular levels. Behaviorally, the Cry1(-/-) mice had a circadian period 1 hr shorter than wild type and the Cry1(-/-)Cry2(-/-) mice were arrhythmic in constant darkness (DD). Biochemically, acute light induction of mPer1 mRNA in the SCN was blunted in Cry1(-/-) and abolished in Cry1(-/-)Cry2(-/-) mice. In contrast, the acute light induction of mPer2 in the SCN was intact in Cry1(-/-) and Cry1(-/-)Cry2(-/-) animals. Importantly, in double mutants, mPer1 expression was constitutively elevated and no rhythmicity was detected in either 12-hr light/12-hr dark or DD, whereas mPer2 expression appeared rhythmic in 12-hr light/12-hr dark, but nonrhythmic in DD with intermediate levels. These results demonstrate that Cry1 and Cry2 are required for the normal expression of circadian behavioral rhythms, as well as circadian rhythms of mPer1 and mPer2 in the SCN. The differential regulation of mPer1 and mPer2 by light in Cry double mutants reveals a surprising complexity in the role of cryptochromes in mammals.

Animals↗
PubMed1999

Effect of antidepressant drug counselling and information leaflets on adherence to drug treatment in primary care: randomised controlled trial.

OBJECTIVES: To evaluate two different methods of improving adherence to antidepressant drugs. DESIGN: Factorial randomised controlled single blind trial of treatment leaflet, drug counselling, both, or treatment as usual. SETTING: Primary care in Wessex PARTICIPANTS: 250 patients starting treatment with tricyclic antidepressants. MAIN OUTCOME MEASURES: Adherence to drug treatment (by confidential self report and electronic monitor); depressive symptoms and health status. RESULTS: 66 (63%) patients continued with drugs to 12 weeks in the counselled group compared with 42 (39%) of those who did not receiving counselling (odds ratio 2.7, 95% confidence interval 1.6 to 4.8; number needed to treat=4). Treatment leaflets had no significant effect on adherence. No differences in depressive symptoms were found between treatment groups overall, although a significant improvement was found in patients with major depressive disorder receiving drug doses of at least 75 mg (depression score 4 (SD 3.7) counselling v 5.9 (SD 5.0) no counselling, P=0.038). CONCLUSIONS: Counselling about drug treatment significantly improved adherence, but clinical benefit was seen only in patients with major depressive disorder receiving doses >/=75 mg. Further research is required to evaluate the effect of this approach in combination with appropriate targeting of treatment and advice about dosage.

Adult↗
PubMed1999

Vancomycin derivatives that inhibit peptidoglycan biosynthesis without binding D-Ala-D-Ala.

Vancomycin is an important drug for the treatment of Gram-positive bacterial infections. Resistance to vancomycin has begun to appear, posing a serious public health threat. Vancomycin analogs containing modified carbohydrates are very active against resistant microorganisms. Results presented here show that these carbohydrate derivatives operate by a different mechanism than vancomycin; moreover, peptide binding is not required for activity. It is proposed that carbohydrate-modified vancomycin compounds are effective against resistant bacteria because they interact directly with bacterial proteins involved in the transglycosylation step of cell wall biosynthesis. These results suggest new strategies for designing glycopeptide antibiotics that overcome bacterial resistance.

Anti-Bacterial Agents↗
PubMed1999

Glyceryl trinitrate and ritodrine in tocolysis: an international multicenter randomized study. GTN Preterm Labour Investigation Group.

OBJECTIVE: To compare the efficacy of transdermal glyceryl trinitrate and intravenous (IV) ritodrine as tocolytics. METHODS: Two hundred forty-five women with preterm labor and intact membranes between 24 and 36 weeks' gestation were randomized to transdermal glyceryl trinitrate or intravenous ritodrine. Treatment was continued until contractions stopped or a maximum of 7 days. Glyceryl trinitrate was administered as a 10- or 20-mg transdermal patch. Intravenous ritodrine was administered according to nationally available guidelines. The primary outcome was prolongation of gestation expressed as a percentage of the time from entry to 37 weeks. Secondary outcomes were proportion of women who delivered the same day, next day, or within 7 and 14 days of entry, and by 32, 34, and 37 weeks. Analysis was by intention to treat. RESULTS: Twelve women (5%) were lost to follow-up. Glyceryl trinitrate and ritodrine prolonged gestation by 74% of time to 37 weeks (difference glyceryl trinitrate-ritodrine 0%; 95% confidence interval (CI) -10%, +10%). There was no significant difference in the proportion of women receiving glyceryl trinitrate or ritodrine who delivered within the specified days from study entry or weeks of gestation; however, 42 women who received glyceryl trinitrate and 58 women who received ritodrine delivered by 37 weeks (difference -11%; 95% CI -24%, +2%). No serious maternal side effects were reported for ritodrine or glyceryl trinitrate. CONCLUSION: We found no overall difference between glyceryl trinitrate and ritodrine in the acute tocolysis of preterm labor but a suggested advantage of glyceryl trinitrate over ritodrine in reducing preterm delivery rate. The maternal side effect profile and treatment discontinuation rates were fewer for glyceryl trinitrate, suggesting it was a safer alternative to ritodrine.

Adolescent↗