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Biomedical subjects

H Lui

Publications and source records attributed to H Lui.

At least 19 recordsLinked to original sources
PubMed2004

Restoration of hair growth in mice with an alopecia areata-like disease using topical anthralin.

Anthralin is a widely used topical anti-psoriatic drug that may have an immunomodulating effect on alopecia areata (AA) as it does in psoriasis. The aims of the present study were to investigate the effects of anthralin on hair growth in balding C3H/HeJ mice affected by an AA-like disease and to study the underlying mechanisms. Affected C3H/HeJ mice were treated daily for 10 weeks on half of the dorsal skin with 0.2% anthralin and the contra-lateral side was treated with the vehicle ointment. The percentage of surface hair coverage and hair density was graded weekly for both sides and hair growth indices were calculated using these two variables. Hair regrowth was observed in 9/14 mice on the treated sides. Four mice displayed near complete replacement of normal density and length hairs. All the vehicle-treated sides showed either no change or continued hair loss. An RNase protection assay (RPA) showed that expression of tumor necrosis factor-alpha (TNF-alpha) and -beta were inhibited by anthralin upon successful treatment. It appears that anthralin may be an effective therapy for C3H/HeJ mice with AA and certain cytokines may be involved in the therapeutic effects of anthralin on restoring hair regrowth in AA-affected C3H/HeJ mice.

Administration, Topical↗
PubMed2004

Efficacy of once-daily treatment regimens with calcipotriol/betamethasone dipropionate ointment and calcipotriol ointment in psoriasis vulgaris.

BACKGROUND: A two-compound ointment containing calcipotriol 50 micro g g-1 and betamethasone dipropionate 0.5 mg g-1 has recently been shown to be an effective treatment for psoriasis. OBJECTIVES: This study was designed to investigate efficacy and safety of different treatment regimens with the two-compound product (Daivobet/Dovobet; LEO Pharma, Ballerup, Denmark) and calcipotriol 50 micro g g-1 ointment (Daivonex/Dovonex; LEO Pharma). METHODS: In total, 972 patients with psoriasis vulgaris were randomized to one of three treatment regimens: group 1, the two-compound product once daily for 8 weeks followed by calcipotriol ointment once daily for 4 weeks; group 2, the two-compound product once daily for 4 weeks followed by 8 weeks of treatment with calcipotriol ointment once daily on weekdays and the two-compound product once daily at weekends; and group 3, calcipotriol ointment twice daily for 12 weeks. The efficacy was evaluated by Psoriasis Area and Severity Index (PASI) and investigators' global assessments of disease severity. The primary response criteria were percentage reduction in PASI and proportion of patients with absent/very mild disease according to the investigators' global assessments after 8 weeks of treatment. RESULTS: The mean reduction in PASI from baseline to the end of 8 weeks of treatment was 73.3% for group 1, 68.2% for group 2 and 64.1% for group 3. The proportion of patients with absent/very mild disease at the end of 8 weeks of treatment was 55.3% for group 1, 47.7% for group 2 and 40.7% for group 3. For both primary response criteria, group 1 was statistically superior to group 3 (P < 0.001), whereas group 2 did not differ significantly from group 3. The difference between group 1 and group 2 was statistically significant with regard to PASI but not regarding the proportion of patients with absent/very mild disease. Patients receiving initial therapy with the two-compound product achieved the fastest treatment response, and the maximum treatment effect for these patients was seen after 5 weeks. This effect was maintained with continued treatment with the two-compound product for up to 8 weeks. After 12 weeks of treatment, no significant differences were seen between the three groups with regard to reduction in PASI, whereas the proportion of patients with absent/very mild disease in group 2 was superior to that in group 3. Patients receiving therapy with the two-compound product experienced fewer lesional/perilesional adverse drug reactions than the calcipotriol-treated patients (P < 0.001): 10.9% in group 1, 11.5% in group 2 and 22.3% in group 3. CONCLUSIONS: Two different short-term treatment regimens employing a recently developed two-compound product (calcipotriol/betamethasone dipropionate) provided rapid and marked clinical efficacy and were shown to be safe therapies for psoriasis vulgaris.

Adolescent↗
PubMed2003

Computerized morphometry and three-dimensional image reconstruction in the evaluation of scalp biopsy from patients with non-cicatricial alopecias.

BACKGROUND: A major challenge in the histopathological examination of scalp biopsies is to perform an adequate evaluation of all the hair follicles present in the tissue. Transverse sectioning is currently the preferred technique to demonstrate every follicular structure in a punch biopsy specimen, although diagnostic accuracy is dependent on subjective evaluation of follicular morphology and hair size. OBJECTIVES: To determine if computer-based morphometry and three-dimensional (3D) image reconstruction software can be used to evaluate scalp biopsies from patients with non-cicatricial alopecias. METHODS: Nine 4-mm scalp punches were taken from nine patients with noncicatricial alopecias and step-sectioned transversely at 0.1-mm intervals from the epidermal surface to the subcutaneous fat. Each tissue section was then digitized and analysed using morphometric and 3D image reconstruction software. Morphometric data and 3D images were collated with clinical and conventional light microscopic diagnoses, as well as follow-up information. RESULTS: In four of the nine patients, results of morphometric analysis concurred with conventional clinicopathological diagnoses. In the remaining five patients, morphometry revealed a lower telogen count in one patient and higher telogen count in four patients. One of the four patients with a higher telogen count also had a low mean hair diameter and miniaturized anagen follicles in the 3D image that were suggestive of early androgenetic alopecia (AGA). 3D virtual microscopic imagery allowed the direct visualization of colour-coded, scaled hair follicles which demonstrated characteristic changes in alopecia areata, AGA and telogen effluvium. CONCLUSIONS: Our study demonstrated the feasibility of using morphometric and 3D reconstruction software to evaluate scalp biopsies. With further validation, this technique may prove to be more sensitive to detect subtle quantitative and qualitative follicular changes in non-cicatricial alopecias.

Adolescent↗
PubMed2003

Once daily application of a combination of calcipotriol and betamethasone dipropionate (Dovobet, Daivobet) for the treatment of psoriasis.

This new compound product containing 50 micrograms/gram calcipotriol and 0.5 milligrams/gram betamethasone dipropionate was recently introduced in Canada for the treatment of psoriasis. Clinical trials demonstrated that this compound was more active than either agent used alone. Recent changes in the product monograph involving the reduction in dose to once daily use has raised questions about the relevance of some previous comparisons of twice daily Dovobet. Pooling the available data from 5,500 patients in clinical trials for Dovobet will allow an inter-trial comparison of the various treatment arms, demonstrating that Dovobet, when applied once daily is significantly more effective than with twice daily applications of either its individual components used alone.

Adult↗
PubMed2001

Systemic photodynamic therapy with aminolaevulinic acid delays the appearance of ultraviolet-induced skin tumours in mice.

BACKGROUND: Photodynamic therapy (PDT) with topical aminolaevulinic acid (ALA) has recently been approved by the US Food and Drug Administration for the treatment of actinic keratoses. OBJECTIVES: To determine whether weekly systemic suberythemogenic ALA-PDT could prevent the appearance of ultraviolet (UV) -induced skin tumours in hairless mice. METHODS: One group of 20 mice received daily UV radiation from FS 20 tubes, and weekly intraperitoneal injections of ALA 40 mg kg(-1), each followed 3 h later by 12 J cm(-2) of white light (ALA-PDT). Control groups consisted of mice exposed only to UV, to UV and ALA without white light, or UV and white light without ALA, as well as untreated mice. RESULTS: The tumour-free survival was significantly longer for mice exposed to daily UV and weekly ALA-PDT as compared with the control groups. Neither the mortality nor the incidence of large skin tumours was higher in the UV/ALA-PDT group than in mice exposed only to UV. In vivo fluorescence spectroscopy showed that the 635-nm fluorescence emission within tumours was lower than in normal skin 3 h after ALA administration. This was also confirmed by quantitative fluorescence microscopy. CONCLUSIONS: Systemic ALA-PDT can delay the appearance of UV-induced skin tumours in mice without increasing mortality or the incidence of large tumours.

Animals↗
PubMed2001

The treatment of moderate to severe psoriasis with a new anti-CD11a monoclonal antibody.

BACKGROUND: Anti-CD11a (hu1124) is a humanized monoclonal antibody directed against the CD11a subunit of LFA-1. This study investigated whether treatment with anti-CD11a antibody provides clinical benefit to patients with moderate to severe plaque psoriasis. METHODS: This was a double-blind, placebo-controlled, phase II, multicenter study. In total, 145 patients with minimum Psoriasis Area and Severity Index scores of 12 and affected body surface area of 10% or more were sequentially enrolled into low-dose (0.1 mg/kg, n = 22) or high-dose (0.3 mg/kg, n = 75) groups. Within groups, patients were randomized to treatment or placebo (n = 48) in a 2:1 ratio. Drug was administered intravenously at weekly intervals for 8 weeks. RESULTS: The percentage of subjects achieving more than 50% improvement in physician's global assessment at day 56 (1 week after final dose) was 15% and 48% for placebo and 0.3 mg/kg of drug, respectively (P =.002). A physician's global assessment of excellent (>75% improvement) was greater in the 0.3 mg/kg group versus placebo (25% vs 2%, P =.0003). Average Psoriasis Area and Severity Index scores at day 56 were 13.9 +/- 7.5 (placebo) and 10.9 +/- 8.4 (0.3 mg/kg) (P <.0001). Epidermal thickness was reduced in the 0.3 mg/kg group compared with the placebo group (37% vs 19%, P =.004). Treatment was well tolerated; mild to moderate flu-like complaints were the most common adverse events. White blood cell counts and lymphocyte counts transiently increased. Depletion of circulating lymphocytes did not occur. CONCLUSIONS: Anti-CD11a antibody administered intravenously in 8 weekly doses of 0.3 mg/kg was well tolerated and induced clinical and histologic improvements in psoriasis.

Adult↗
PubMed2001

Oral aminolevulinic acid induces protoporphyrin IX fluorescence in psoriatic plaques and peripheral blood cells.

Photodynamic therapy (PDT) with topical aminolevulinic acid (ALA) has been shown in previous studies to improve psoriasis. However, topical ALA-PDT may not be practical for the treatment of extensive disease. In order to overcome this limitation we have explored the potential use of oral ALA administration in psoriatic patients. Twelve patients with plaque psoriasis received a single oral ALA dose of 10, 20 or 30 mg/kg followed by measurement of protoporphyrin IX (PpIX) fluorescence in the skin and circulating blood cells. Skin PpIX levels were determined over time after ALA administration by the quantification of the 635 nm PpIX emission peak with in vivo fluorescence spectroscopy under 442 nm laser excitation. Administration of ALA at 20 and 30 mg/kg induced preferential accumulation of PpIX in psoriatic as opposed to adjacent normal skin. Peak fluorescence intensity in psoriatic and normal skin occurred between 3 and 5 h after the administration of 20 and 30 mg/kg, respectively. Ratios of up to 10 for PpIX fluorescence between psoriatic versus normal skin were obtained at the 30 mg/kg dose of ALA. Visible PpIX fluorescence was also observed on normal facial skin, and nonspecific skin photosensitivity occurred only in patients who received the 20 or 30 mg/kg doses. PpIX fluorescence intensity was measured in circulating blood cells by flow cytometry. PpIX fluorescence was higher in monocytes and neutrophils as compared to CD4+ and CD8+ T lymphocytes. PpIX levels in these cells were higher in patients who received higher ALA doses and peaked between 4 and 8 h after administration of ALA. There was only a modest increase in PpIX levels in circulating CD4+ and CD8+ T lymphocytes. In conclusion oral administration of ALA induced preferential accumulation of PpIX in psoriatic plaques as compared to adjacent normal skin suggesting that PDT with oral ALA should be further explored for the treatment of psoriasis.

Administration, Oral↗
PubMed2001

Vaniqa--eflornithine 13.9% cream.

Eflornithine HCl 13.9% cream is the first topical prescription treatment to be approved by the US FDA for the reduction of unwanted facial hair in women. It irreversibly inhibits ornithine decarboxylase (ODC), an enzyme that catalyzes the rate-limiting step for follicular polyamine synthesis, which is necessary for hair growth. In clinical trials eflornithine cream slowed the growth of unwanted facial hair in up to 60% of women. Improvement occurs gradually over a period of 4-8 weeks or longer. Most reported adverse reactions consisted of minor skin irritation.

Administration, Topical↗
PubMed2001

Predictive model for immunotherapy of alopecia areata with diphencyprone.

BACKGROUND: Immunotherapy with diphencyprone (diphenylcyclopropenone) is used in the treatment of alopecia areata (AA). Response rates have varied in the literature. OBJECTIVES: To determine the efficacy of diphencyprone therapy for AA in the largest reported cohort of patients; to identify patient and treatment factors predictive of therapeutic success; and to develop a practical model for predicting patient response. METHODS: The medical records of 148 consecutive patients treated with diphencyprone were reviewed. A clinically significant response to diphencyprone therapy was defined as a cosmetically acceptable response or greater than 75% terminal hair regrowth. Survival analyses using the Kaplan-Meier method and the Cox proportional hazards model were performed to determine significant factors predictive of regrowth and relapse. RESULTS: Using a survival analysis model, the cumulative patient response at 32 months was 77.9% (95% confidence interval, 56.8%-98.9%). Variables independently associated with clinically significant regrowth were age at onset of disease and baseline extent of AA. Older age at onset of AA portended a better prognosis. A cosmetically acceptable end point was obtained in 17.4% of patients with alopecia totalis/universalis, 60.3% with 75% to 99% AA, 88.1% with 50% to 74% AA, and 100% with 25% to 49% AA. A lag of 3 months was present between initiation of therapy and development of significant hair regrowth in the first responders. Relapse after achieving significant regrowth developed in 62.6% of patients. CONCLUSIONS: Response to diphencyprone treatment in AA is affected by baseline extent of AA and age at disease onset. A prolonged treatment course might be necessary. A predictive model has been developed to assist with patient prognostication and counseling.

Adolescent↗
PubMed2000

Topical photodynamic therapy with 5-aminolaevulinic acid does not induce hair regrowth in patients with extensive alopecia areata.

BACKGROUND: Photodynamic therapy (PDT) is a new modality involving the administration of a photosensitizer, or photosensitizer precursor, followed by its activation with light to generate a therapeutic effect. 5-Aminolaevulinic acid (ALA) is a photosensitizer precursor that is transformed by cells into protoporphyrin IX (PpIX), which can in turn be activated by red light. OBJECTIVES: To investigate the effect of PDT in alopecia areata (AA). METHODS: In six patients with extensive AA, topical ALA lotion at 5%, 10% and 20% as well as the vehicle lotion alone were applied separately to different scalp areas, followed 3 h later by exposure to red light at each treatment session. RESULTS: No significant hair growth was observed after 20 twice-weekly treatment sessions. A significant increase in erythema and pigmentation was observed for the three concentrations of ALA lotion vs. the vehicle, implying that a phototoxic PDT effect was achieved in the skin. In vivo fluorescence spectroscopy in one patient showed an increase in red PpIX fluorescence 3 h after ALA application followed by a decrease after light exposure. On fluorescence microscopy, bright red fluorescence was present in the epidermis and sebaceous glands, but not in the inflammatory infiltrate surrounding the hair follicle following ALA application. CONCLUSIONS: PDT was ineffective in the treatment of AA.

Adult↗
PubMed2000

The Arabidopsis Cdc2a-interacting protein ICK2 is structurally related to ICK1 and is a potent inhibitor of cyclin-dependent kinase activity in vitro.

Cyclin-dependent kinases (CDKs) are important regulators of the eukaryotic cell division cycle. To study protein-protein interactions involving plant CDKs, the Arabidopsis thaliana Cdc2aAt was used as bait in the yeast two-hybrid system. Here we report on the isolation of ICK2, and show that it interacts with Cdc2aAt, but not with a second CDK from Arabidopsis, Cdc2bAt. ICK2 contains a carboxy-terminal domain related to that of ICK1, a previously described CDK inhibitor from Arabidopsis, and to the CDK-binding domain of the mammalian inhibitor p27Kip1. Outside of this domain, ICK2 is distinct from ICK1, p27Kip1, and other proteins. At nanogram levels (8 nM), purified recombinant ICK2 inhibits p13Suc1-associated histone H1 kinase activity from Arabidopsis tissue extracts, demonstrating that it is a potent inhibitor of plant CDK activity in vitro. ICK2 mRNA was present in all tissues analysed by Northern hybridization, and its distribution was distinct from that of ICK1. These results demonstrate that plants possess a family of differentially regulated CDK inhibitors that contain a conserved carboxy terminal but with distinct amino terminal regions.

Amino Acid Sequence↗
PubMed2000

Practical management of hair loss.

OBJECTIVE: To describe an organized diagnostic approach for both nonscarring and scarring alopecias to help family physicians establish an accurate in-office diagnosis. To explain when ancillary laboratory workup is necessary to confirm the diagnosis. QUALITY OF EVIDENCE: Current diagnostic and therapeutic interventions for hair loss are based on randomized controlled studies, uncontrolled studies, and case series. MEDLINE was searched from January 1966 to December 1998 with the MeSH words alopecia, hair, and alopecia areata. Articles were selected on the basis of experimental design, with priority given to the most current large multicentre controlled studies. Overall global evidence for therapeutic intervention for hair loss is quite strong. MAIN MESSAGE: The most common forms of nonscarring alopecias are androgenic alopecia, telogen effluvium, and alopecia areata. Other disorders include trichotillomania, traction alopecia, tinea capitis, and hair shaft abnormalities. Scarring alopecia is caused by trauma, infections, discoid lupus erythematosus, or lichen planus. Key to establishing an accurate diagnosis is a detailed history, including medication use, systemic illnesses, endocrine dysfunction, hair-care practices, and family history. All hair-bearing sites should be examined. A 4-mm punch biopsy of the scalp is useful, particularly to diagnose scarring alopecias. Once a diagnosis has been established, specific therapy can be initiated. CONCLUSIONS: Diagnosis and management of hair loss is an interesting challenge for family physicians. An organized approach to recognizing characteristic differential features of hair loss disorders is key to diagnosis and management.

Adult↗
PubMed1999

Excess tissue friability during CO2 laser vaporization of nodular amyloidosis.

BACKGROUND: Nodular amyloidosis is a rare cutaneous disorder for which many treatments have been described, including carbon dioxide (CO2) laser vaporization. OBJECTIVE: We describe the intraoperative tissue effects encountered during successful treatment of nodular amyloidosis with CO2 laser surgery. METHODS: Two nodules of cutaneous amyloid on the nose of a patient were vaporized with a defocused, continuous-wave CO2 laser. RESULTS: The tissue was found to be highly friable and hemostasis was difficult to achieve during the surgery. These clinical observations were correlated with amyloid infiltration of the dermis and blood vessels on preoperative histologic examination. CONCLUSION: CO2 laser vaporization of nodular amyloidosis may be associated with prominent tissue friability and poor hemostasis.

Amyloidosis↗
PubMed1999

Treatment of refractory solar urticaria with plasma exchange.

BACKGROUND: Solar urticaria is a photodermatosis that can be very disabling for patients who are highly sensitive to light and can also be very resistant to therapy. OBJECTIVE: To correlate the results of serial phototesting in a patient with severe and refractory solar urticaria before and after treatment with plasma exchange. METHODS: Plasma exchange was performed five times over a period of 10 days. Phototesting to ultraviolet A (UVA) irradiation and visible light was performed with fluorescent ultraviolet tubes and an incandescent lamp. RESULTS: The urticaria that developed after very low light doses during baseline phototesting could not be provoked following plasma exchange. The patient is now almost symptom-free, with only occasional and transient hives more than 21 months after her last plasma exchange. CONCLUSIONS: Plasma exchange is a therapeutic modality to consider in highly light-sensitive patients when other treatments have failed.

Adult↗
PubMed1998

Advances in dermatologic lasers.

Lasers continue to fundamentally redefine the nature of dermatologic practice. Recent advances in dermatologic lasers have focused on refining the process of selective photothermolysis, as well as evaluating new devices and treatment indications. Despite the current multiplicity of available lasers and associated marketing claims, what is perhaps most lacking are data comparing the efficacy of different lasers that can be used to treat the same condition, and data on the long term benefits of laser treatment.

Clinical Trials as Topic↗