bluuebunny/crossref_metadata_2025_split huggingface dataset:
A retrospective review of PUVA therapy at the National Skin Centre of Singapore
Authors: Tran D. , Kwok Y. K. , Goh C. L. 
Published: March 2003

Background: Photochemotherapy (PUVA) is beneficial for the treatment of various dermatoses. The introduction of ultraviolet B and narrow‐band ultraviolet B phototherapy has had a significant impact on the role of PUVA in dermatology. This study aims to assess the current role of PUVA in treating dermatoses, in a predominantly Asian population, at the National Skin Centre in Singapore.Materials and methods:We reviewed the clinical data of 115 patients who were started on PUVA treatment at the National Skin Centre, Singapore in 1998. We analysed the epidemiology data, the clinical response rate and the adverse effects of PUVA therapy. All of the patients continued to have ongoing maintenance treatment.Results: Most of our patients were Chinese (74.8%) and male (58.3%), ranging from the ages of 4 to 74 years. Vitiligo (60.9%) was the commonest skin disorder treated with PUVA, followed by psoriasis (20.9%), endogenous eczema (11.3%), mycosis fungoides (3.5%), lichen amyloidosis (2.6%) and prurigo nodularis (0.9%). Most of our patients received paint PUVA (50.4%), 33.9% oral PUVA and 15.7% bath PUVA. The best clinical response – those patients achieving a greater that 50% clearance – was observed in patients with endogenous eczema, psoriasis and mycosis fungoides (76.8%, 73.9% and 60%, respectively). Of the vitiliginous patients, 54.3% experienced a poor response to PUVA therapy. The main side effects were mild erythema and pruritus.Conclusion: PUVA remains a valuable, well‐tolerated therapeutic option for a variety of dermatoses.
Ultraviolet radiation enhances both the nodular and ulcerative forms of Mycobacterium ulcerans infection in a Crl:IAF(HA)‐hrBR hairless guinea pig model of Buruli ulcer disease
Authors: Cope R. B. , Hartman J. A. , Morrow C. K. , Haschek W. M. , Small P. L. C. 
Published: March 2003

Background:
Ultraviolet radiation (UV) pre‐exposure enhances intracellular mycobacterial infections, however, its effect upon the pathogenesis of the extracellular Mycobacterium ulcerans parasite had not been previously examined. The hypothesis tested was that UV pre‐exposure enhances both the nodular and ulcerative forms of M. ulcerans infection in the Crl:IAF(HA)‐hrBR hairless guinea pig. Methods:
Groups of five animals were exposed to total cumulative UV doses of 0 (control), 3 or 30 kJ/m2 followed 3 days later by subcutaneous infection with 3 × 104 CFU of M. ulcerans in order to induce the nodular form of the disease. The resultant nodules were then measured for the next 22 days. The experiment was then repeated using intradermal infection with 2 × 106 CFU in order to induce the ulcerative form of the disease. The resultant ulcers were measured for the next 30 days. In both experiments, the animals were tested for delayed‐type hypersensitivity (DTH) reactivity to Burulin‐S as a marker of the onset of the reactive phase of the disease. Results:
Following low inoculum subcutaneous infection, distinct, well‐demarcated, subcutaneously situated skin nodules were present at infected skin sites between 7 and 22 days post‐infection. Between days 14 and 21, the mean nodule diameters of the UV irradiated groups were significantly (P < 0.03) greater than that of the control group. UV pre‐exposure resulted in significant (P < 0.035) suppression of DTH responses to Burulin‐S challenge. High inoculum intradermal infection resulted in the development of ulcerative lesions. Between 10 and 30 days post‐infection, the mean lesion diameters and mean ulcer development times of UV irradiated groups were significantly (P < 0.05) greater than those of the controls. However, UV irradiation did not affect DTH responses to Burulins in the high inoculum experiment. In both experiments, the lesions were histologically consistent with human Buruli ulcer disease. These results demonstrate that UV pre‐exposure results in enhanced M. ulcerans infection in the hairless guinea pig model of Buruli ulcer disease and suggest that UV exposure may be a relevant factor in the pathogenesis of human forms of the disease.
Effects of subchronic and chronic melatonin treatment on somatostatin binding and its effects on adenylyl cyclase activity in the rat frontoparietal cortex
Authors: Izquierdo‐Claros Rosa María , Boyano‐Adánez María del Carmen , Arilla‐Ferreiro Eduardo 
Published: March 2003

Abstract: Melatonin and somatostatin are known to exert similar effects on locomotor activity. We have previously demonstrated that acute melatonin treatment regulates somatostatin receptor function in the rat frontoparietal cortex. However, the effects of subchronic and chronic melatonin treatment on the somatostatin receptor‐G protein–adenylyl cyclase system in the rat frontoparietal cortex are unknown. Melatonin was administered subcutaneously at a daily dose of 25 μg/kg for 4 days, 1 wk or 2 wk. Twenty‐four hours after the last injection, the animals were sacrificed. Melatonin did not alter the somatostatin‐like immunoreactivity content in the frontoparietal cortex from control and melatonin‐treated rats during any of the previously indicated periods. Four days of melatonin administration induced both an increase in the number of [125I]‐Tyr11‐somatostatin receptors and a decrease in the affinity of somatostatin for its receptors in frontoparietal cortical membranes. The increased number of somatostatin receptors in the melatonin‐treated rats was associated with an increased capacity of somatostatin to inhibit basal and forskolin‐stimulated adenylyl cyclase activity. Melatonin administration for 4 days induced a higher adenylyl cyclase activity both under basal conditions and after direct stimulation of the enzyme with forskolin. No significant differences were observed in the function of Gi proteins in the 4‐day melatonin‐treated rats. Western blot analyses showed that the 4‐day melatonin treatment reduced Giα2 levels, without altering the amount of Giα1. These melatonin‐induced changes reverted to control values after 7 or 14 days of treatment. Altogether, the present findings suggest that subchronic melatonin treatment modulates the somatostatin receptor/effector system in the rat frontoparietal cortex.
Reproducibility of repeated measurements on healthy skin with Minolta Chromameter CR‐300
Authors: Kerckhove Eric , Staes Filip , Flour Mieke , Stappaerts Karel , Boeckx Willy 
Published: March 2003

Background/aims: In this report the reproducibility of measurements with the Minolta Chromameter CR‐300 on healthy skin was investigated.Methods: Intra‐ and inter‐rater reproducibility, reproducibility with two instruments and repeated measurements with a 1 week time lapse were examined on healthy skin of 30 volunteers by means of intra‐class correlation coefficients (ICC) and standard error of measurements (SEM).Results: Results showed excellent values for ICC in all the four conditions.Conclusions: On the basis of these results we concluded that the instrument provides reliable information and can be used in comparative clinical trials.
Impact of stress of marital dissolution on skin barrier recovery: tape stripping and measurement of trans‐epidermal water loss (TEWL)
Authors: Muizzuddin Neelam , Matsui Mary S. , Marenus Kenneth D. , Maes Daniel H. 
Published: March 2003

Background: Psychological stress of marital disruption is associated with significant increases in a variety of psychological and physical disorders. The effect of stress on the immune system is well documented and skin disorders have been reported to exacerbate during stressful situations. This study was designed to observe the effects of stress on skin barrier strength and recovery. Twenty‐eight healthy females age 21–45 who were in the process of marital separation were tested for skin barrier strength and recovery. The panel was chosen on the basis of the intensity of self perceived stress. The control group was an age‐matched group of self perceived ‘happy’ subjects. Servomed evaporimeter was used to measure trans‐epidermal water loss (TEWL) from cheek area of the face, before and after removing stratum corneum layers with tape strippings. Skin barrier strength was defined as the number of tape strippings required to disrupt skin barrier, which is a TEWL of 18 g/m2/h or more. Barrier recovery was denoted by the level of TEWL, 3 h and 24 h after barrier disruption.Results: There was no correlation between the degree of stress and barrier strength. However, individuals with high stress recovered slower than the individuals with low stress after 3 h (R = 0.64) and 24 h (R = 0.74).Conclusions: Psychological stress of marital dissolution does not appear to change skin barrier strength but has a negative impact on skin barrier recovery.
Analysis of skin line pattern for lesion classification
Authors: She Zhishun , Fish Peter J. 
Published: March 2003

Background/purpose: It has been observed that skin patterning tends to be disrupted by malignant but not by benign skin lesions. This suggests that measurements of skin pattern disruption on simply captured white light optical skin images could be a useful contribution to a diagnostic feature set. Previous work using a measurement of line strength by a consistent high‐value profiling technique followed by local variance measurement or a region agglomerative classifier to measure skin line pattern disruption was extremely promising but computationally intensive, suggesting that the idea of measuring skin pattern disruption was useful but a simpler method was required.Methods: The skin pattern was extracted by high‐pass filtration and enhanced by adaptive anisotropic (spatial variant) filtering which smoothes along skin lines but not across them. The skin line main direction and direction variance were estimated using a local image gradient matrix and the difference of these measures across the lesion image boundary was used as a lesion classifier.Results: A set of images of malignant melanoma and benign naevi were processed as above and the scatter plot of results in a two‐dimensional feature (line direction and line variation difference) space showed excellent separation of benign and malignant lesions. An ROC plot enclosed an area of 0.88.Conclusions: The experimental results showed that the local line direction and the local line variation were promising features for distinguishing malignant melanoma from benign lesion and the methods used were effective and computationally low‐cost.
Iron and vitamin deficiencies, endocrine and immune status in patients with primary Sjögren's syndrome
Authors: Lundström IMC , Lindström FD 
Published: March 2003

OBJECTIVES: To study the prevalence of iron and vitamin deficiencies, endocrine disorders and immunological parameters in patients with primary Sjögren's syndrome (1°SS).DESIGN AND SUBJECTS: At the time of the establishment of the diagnosis of 1°SS in 43 consecutive patients, a clinical examination including haematological analyses was performed. The patients' medical records were also reviewed.SETTING: Patients referred for diagnosis to The University Hospital, Linköping, a secondary or tertiary referral hospital serving the middle part of southern Sweden.RESULTS: In total, current or previously treated iron and vitamin deficiencies were registered for 63% of the 1°SS patients (iron 51%, vitamin B12 25%, folate 9%). Current low ferritin was noted in 24%, low iron saturation in 37%, decreased vitamin B12 in 13% and folate in 9%. Thyroid disease was found in a total of 33% and 30% had had autoimmune thyroiditis. Three patients (7%) had verified diabetes mellitus. Erythrocyte sedimentation rate (ESR) was raised in 65% of the patients and 84% had a polyclonal increase of Ig. Rheumatoid factor (RF) was detected in 85%, antinuclear antibody (ANA) in 74%, anti‐SS‐A in 88% and anti‐SS‐B in 73% of the patients.CONCLUSION: Iron and vitamin deficiencies and thyroid diseases are common in patients with 1°SS. Since these disorders often are treatable and may affect the patients' distress as well as their immune and exocrine function, an active, recurrent search for deficiencies, endocrine diseases and other frequently recorded disorders is recommended.
Oral lichen planus: a preliminary clinical study on treatment with tazarotene
Authors: Petruzzi M , De Benedittis M , Grassi R , Cassano N , Vena G , Serpico R 
Published: March 2003

OBJECTIVE: The rationale for using tazarotene in oral lichen planus (OLP) is its regulatory action on the growth and differentiation of keratinocytes and on inflammation. This randomized, placebo‐controlled study addresses evaluation of the effects of topic tazarotene in the treatment of OLP.DESIGN: The degree of lesions before and after treatment scored by a 6‐score scale in six cases treated with tazarotene was statistically compared with those of six controls treated with placebo.SUBJECTS: Twelve patients with hyperkeratosic OLP were randomly allocated to treatment with tazarotene gel 0.1% b.i.d. or with placebo for eight consecutive weeks.METHODS: The statistical comparison was executed by means of Wilcoxon analysis for paired data.RESULTS: Patients treated with tazarotene presented a significant reduction of their lesions as compared with the control group. Among transitory side‐effects, burning sensation and taste abnormalities were observed.CONCLUSION: Topical tazarotene may be a valuable therapeutic tool in the treatment of hyperkeratotic OLP.
Telomeres, Telomerase, and Telomerase Inhibition: Clinical Implications for Cancer
Authors: Ahmed Ali , Tollefsbol Trygve 
Published: March 2003

Telomeres are located at the ends of eukaryotic chromosomes. The enzyme telomerase synthesized them, and they are responsible for maintaining the lengths of chromosomes. Absence of telomerase is associated with telomere shortening and aging of somatic cells, but high telomerase activity is observed in over 90% of human cancer cells. Although the disappearance of telomerase with aging is considered a natural defense against development of cancer, it is not known what triggers the reappearance of telomerase in cancer cells. Telomerase activity is directly correlated with the expression of its active catalytic component, the human telomerase reverse transcriptase (hTERT), which is controlled primarily at the level of transcription.An earlier paper discussed the relationship of telomerase with aging. In this article, the contemporary literature is reviewed to explore the associations between telomerase, telomerase inhibition, and cancer. Because most cancers occur in old age, with the aging of the population, the number of people suffering from cancer is expected to increase in the coming decades. It is not known what roles telomerase and hTERT play in the complex relationship between aging and cancer. Data from experimental studies suggest that telomerase assay could potentially play a role in the diagnosis and prognosis of cancers. There is also evidence that telomerase inhibitors might be used as anticancer agents. As the knowledge of the relationships between telomerase and cancer and between telomerase and aging advances, it is hoped that more about the interacting relationships between telomerase, aging, and cancer will be learned.
Effects of Early Undernutrition on the Brain Insulin‐Like Growth Factor‐I System
Authors: Chowen J. A. , Goya L. , Ramos S. , Busiguina S. , García‐Segura L. M. , Argente J. , Pascual‐Leone A. M. 
Published: March 2003

AbstractUndernutrition reduces circulating concentrations of insulin‐like growth factor (IGF)‐I, but how it affects the brain IGF system, especially during development, is largely unknown. We have studied IGF‐I, IGF‐II, IGF receptor and IGF binding protein (BP)‐2 mRNA expression in the hypothalamus, cerebellum and cerebral cortex of neonatal rats that were food restricted beginning on gestational day 16. One group was refed starting on postnatal day 14. Rats were killed on postnatal day 8 or 22. Undernutrition did not produce an overall reduction in brain weight at either age but, at 22 days, both the cerebellum and hypothalamus weighed significantly less. At 8 days, no change was detected in the central IGF axis in response to undernutrition. However, in 22‐day‐old undernourished rats, IGF‐I and IGF receptor mRNA expression were increased in both the hypothalamus and cerebellum, while IGFBP‐2 was decreased, but only in the hypothalamus. Refeeding had no effect on any of these parameters. These results suggest that the hypothalamus and cerebellum respond to malnutrition and the decrease in circulating IGF‐I, a peptide fundamental for growth and development, by increasing the local production of both the growth factor and its receptor in attempt to maintain normal development.
The role of epidermal turgor in stomatal interactions following a local perturbation in humidity
Authors: Mott K. A. , Franks P. J. 
Published: March 2003

AbstractHumidity in a small area of a Vicia faba L. leaf was perturbed with a flow of dry air from an 80 µm (inside diameter) needle, while the remainder of the leaf was maintained at high and constant humidity. The influence of the needle flow on the humidity at the leaf surface was quantified by using a spatially explicit dewpoint hygrometer to observe condensation patterns. When the dry air from a needle was applied to the leaf, stomata within the influence of the needle opened within the first few minutes of the perturbation, and local epidermal turgor pressure declined within the same time frame. When the needle flow was removed from the leaf, these responses were reversed, but with more variable kinetics. Stomata and epidermal cells outside the influence of the needle flow, which were exposed to a constant and high humidity, showed similar, but smaller, responses when the needle flow was applied to the leaf. Since the opening of these stomata should have had only a small effect on transpiration (because of the high humidity), it is likely that the reduction in epidermal turgor was the cause (rather than the result) of the stomatal opening. The magnitude of the turgor response was only loosely related to the distance from the needle flow up to distances of almost 400 µm. The data support the idea that neighbouring stomata can interact through the influence of transpiration on epidermal turgor.
A quantitative study of day–night changes in the spatial distribution of insects in a stony stream
Authors: Elliott J. M. 
Published: March 2003

Summary

As many invertebrates are nocturnal, their spatial distribution may change from day to night. This behavioural aspect of their population dynamics has been ignored, but is now examined for the first time by testing the hypotheses: (i) a power function was a suitable model for the spatial distribution of common species of Ephemeroptera, Plecoptera and Trichoptera in a stony stream; (ii) the spatial distribution varied between species but was similar within species for larvae greater and smaller than half‐size; (iii) diurnal and nocturnal spatial distributions were significantly different for each species. To ensure that the conclusions were consistent, large samples (n = 30) were taken near midday and midnight in April, June and November over 4 years.
Twenty–one species were taken in sufficient numbers for the analyses; seven species were too sparse to be included. The first hypothesis was supported. A power function, relating spatial variance (s2) to mean (m), was an excellent fit in all the analyses (P < 0·001, r2 > 0·95), i.e. the spatial variance was density–dependent. The power b, often used as an ‘index of aggregation’, varied in the range 0·88–2·50.
Most analyses supported the second hypothesis. For four species, the difference between the two size groups was just significant (P < 0·05), but was due to inadequate data for three species. Large larvae of the fourth species, the caddis Odontocerum albicorne, were less aggregated than small larvae at night, and were the only group with a b‐value less than one.
The third hypothesis was partially supported. The distribution did not change significantly (P > 0·05) for nine species; five burrowers in gravel, moss or mud, two highly mobile predators, one sedentary, case–building, Trichoptera species, and one net–spinning Trichoptera species. Aggregation was reduced significantly (P < 0·001) at night for four species, all case–building Trichoptera larvae. Aggregation increased significantly (P < 0·001) at night, except at low densities, for the remaining eight species, one being a nocturnal predator and the others being herbivorous species; all occurred frequently in night samples of invertebrate drift. Day–night changes in spatial distribution were therefore an essential part of the behavioural dynamics of 12 of the 21 species, and should be investigated in other species, including terrestrial species.
The distribution of the anti‐HIV drug, 2′3′‐dideoxycytidine (ddC), across the blood–brain and blood–cerebrospinal fluid barriers and the influence of organic anion transport inhibitors
Authors: Gibbs J. E. , Thomas S. A. 
Published: March 2003

AbstractThe brain and CSF distribution of the HIV reverse transcriptase inhibitor, 2′3′‐dideoxycytidine (ddC), was investigated by the in situ brain perfusion and isolated incubated choroid plexus methods in the guinea pig. Multiple‐time brain perfusions indicated that the distribution of [3H]ddC to the brain and CSF was low and the unidirectional rate constant (Kin) for the brain uptake of this nucleoside analogue (0.52 ± 0.10 µL/min/g) was not significantly different to that for the vascular marker, [14C]mannitol (0.44 ± 0.09 µL/min/g). The influence of unlabelled ddC, six organic anion transport inhibitors and 3′‐azido 3′‐deoxythymidine (AZT) on the CNS uptake of [3H]ddC was examined in situ and in vitro. ddC, probenecid and 2,4‐dichlorophenoxyacetic acid altered the distribution of [3H]ddC into the brain and choroid plexuses, indicating that the limited distribution of [3H]ddC was a result of an organic anion efflux transporter, in addition to the low lipophilicity of this drug (octanol‐saline partition coefficient, 0.047 ± 0.001). The CNS distribution was also sensitive to p‐aminohippurate and deltorphin II, but not digoxin, suggesting the involvement of organic anion transporters (OAT1/OAT3‐like) and organic anion transporting polypeptides (OATP1/OATPA‐like). AZT did not effect the accumulation of [3H]ddC, indicating that when these nucleoside analogues are used in anti‐HIV combination therapy, the CNS distribution of ddC is unchanged.
Mitochondria regulate Ca2+ wave initiation and inositol trisphosphate signal transduction in oligodendrocyte progenitors
Authors: Haak Laurel L. , Grimaldi Maurizio , Smaili Soraya S. , Russell James T. 
Published: March 2003

AbstractMitochondria in oligodendrocyte progenitor cells (OPs) take up and release cytosolic Ca2+ during agonist‐evoked Ca2+ waves, but it is not clear whether or how they regulate Ca2+ signaling in OPs. We asked whether mitochondria play an active role during agonist‐evoked Ca2+ release from intracellular stores. Ca2+ puffs, wave initiation, and wave propagation were measured in fluo‐4 loaded OP processes using linescan confocal microscopy. Mitochondrial depolarization, measured by tetramethyl rhodamine ethyl ester (TMRE) fluorescence, accompanied Ca2+ puffs and waves. In addition, waves initiated only where mitochondria were localized. To determine whether energized mitochondria were necessary for wave generation, we blocked mitochondrial function with the electron transport chain inhibitor antimycin A (AA) in combination with oligomycin. AA decreased wave speed and puff probability. These effects were not due to global changes in ATP. We found that AA increased cytosolic Ca2+, markedly reduced agonist‐evoked inositol trisphosphate (IP3) production, and also enhanced phosphatidylinositol 4,5‐bisphosphate (PIP2) binding to the Ca2+ dependent protein gelsolin. Thus, the reduction in puff probability and wave speed after AA treatment may be explained by competition for PIP2 between phospholipase C and gelsolin. Energized mitochondria and low cytosolic Ca2+ concentration may be required to maintain PIP2, a substrate for IP3 signal transduction.