Chao-Chun Yang

National Cheng Kung University Hospital, Tainan, Taiwan, Taiwan

Are you Chao-Chun Yang?

Claim your profile

Publications (18)59.92 Total impact

  • Article: Linear lupus panniculitis of the scalp presenting as alopecia along Blaschko's lines: a distinct variant of lupus panniculitis in East Asians?
    [show abstract] [hide abstract]
    ABSTRACT: A 32-year-old Taiwanese man presented to our clinic with a 6-month history of linear hair loss in a wavy and curved pattern across the parietal and occipital scalp, resembling the distribution of Blaschko's lines. Physical examination showed interfollicular erythema and follicular plugging without skin atrophy or sclerotic change. Histopathology revealed a lymphoplasmacytic infiltrate in the perifollicular dermis and subcutis with abundant mucin deposition, consistent with the diagnosis of lupus panniculitis. Treatment with hydroxychloroquine and local steroid injection resulted in complete hair regrowth but recurrence was noted. Linear lupus panniculitis of the scalp presenting as alopecia along Blaschko's lines had so far been reported exclusively in five East Asians. Apart from classical lupus panniculitis, it had distinct clinical and histopathological features such as younger age of onset, male predominance, reversible clinical course without scarring, fewer associations with systemic lupus erythematosus, exclusive involvement of scalp, sparse inflammatory infiltration, abundant mucin deposition, higher degree of hyaline fat degeneration and negative results of immunofluorescent studies. Therefore, we propose linear lupus panniculitis of the scalp to be a distinct variant of lupus panniculitis and should be included in the differential diagnosis for focal or linear alopecia, especially in East Asians.
    The Journal of Dermatology 12/2011; 39(4):385-8. · 1.49 Impact Factor
  • Article: Bald scalp in men with androgenetic alopecia retains hair follicle stem cells but lacks CD200-rich and CD34-positive hair follicle progenitor cells.
    [show abstract] [hide abstract]
    ABSTRACT: Androgenetic alopecia (AGA), also known as common baldness, is characterized by a marked decrease in hair follicle size, which could be related to the loss of hair follicle stem or progenitor cells. To test this hypothesis, we analyzed bald and non-bald scalp from AGA individuals for the presence of hair follicle stem and progenitor cells. Cells expressing cytokeratin15 (KRT15), CD200, CD34, and integrin, α6 (ITGA6) were quantitated via flow cytometry. High levels of KRT15 expression correlated with stem cell properties of small cell size and quiescence. These KRT15(hi) stem cells were maintained in bald scalp samples. However, CD200(hi)ITGA6(hi) and CD34(hi) cell populations--which both possessed a progenitor phenotype, in that they localized closely to the stem cell-rich bulge area but were larger and more proliferative than the KRT15(hi) stem cells--were markedly diminished. In functional assays, analogous CD200(hi)Itga6(hi) cells from murine hair follicles were multipotent and generated new hair follicles in skin reconstitution assays. These findings support the notion that a defect in conversion of hair follicle stem cells to progenitor cells plays a role in the pathogenesis of AGA.
    The Journal of clinical investigation 02/2011; 121(2):613-22. · 15.39 Impact Factor
  • Article: Hair loss in elderly women.
    [show abstract] [hide abstract]
    ABSTRACT: Hair loss in elderly women has been becoming a major topic in the daily practice of dermatology. Aging of hair follicles seems to affect hair growth and pigmentation, the molecular mechanisms of which remain to be elucidated. Further senile changes in physiology and immunity may influence the onset and course of hair diseases. Some preexisting diseases such as androgenetic alopecia usually worsen after menopause, while others, like discoid lupus erythematosus, may attenuate. Hormone surveying, especially with regard to internal androgen-producing tumors, is indicated in postmenopausal women with androgenetic alopecia of sudden exacerbation or with unusual manifestation or other virilizing signs. The prevalence of alopecia totalis and alopecia universalis appears to be much lower in postmenopausal ages as compared to earlier onset. Acute or chronic telogen effluvium is not uncommonly superimposed on androgenetic alopecia. Trichotillomania shows a marked female predominance in the senile age group with a higher rate of psychopathology. Worldwide, tinea capitis has been increasingly observed in postmenopausal women. Frontal fibrosing alopecia, giant cell arteritis and erosive pustular dermatosis involve mainly elder women leading to scarring alopecia. Alopecia induced by tumor metastasis to the scalp must be considered in women with underlying neoplasms, especially breast cancer. Overall, hair loss in postmenopausal women is often multifactorial and warrants a close inspection.
    European journal of dermatology: EJD 02/2010; 20(2):145-51. · 2.53 Impact Factor
  • Article: Review of hair follicle dermal cells.
    Chao-Chun Yang, George Cotsarelis
    [show abstract] [hide abstract]
    ABSTRACT: Hair follicle stem cells in the epithelial bulge are responsible for the continual regeneration of the hair follicle during cycling. The bulge cells reside in a niche composed of dermal cells. The dermal compartment of the hair follicle consists of the dermal papilla and dermal sheath. Interactions between hair follicle epithelial and dermal cells are necessary for hair follicle morphogenesis during development and in hair reconstitution assays. Dermal papilla and dermal sheath cells express specific markers and possess distinctive morphology and behavior in culture. These cells can induce hair follicle differentiation in epithelial cells and are required in hair reconstitution assays either in the form of intact tissue, dissociated freshly prepared cells or cultured cells. This review will focus on hair follicle dermal cells since most therapeutic efforts to date have concentrated on this aspect of the hair follicle, with the idea that enriching hair-inductive dermal cell populations and expanding their number by culture while maintaining their properties, will establish an efficient hair reconstitution assay that could eventually have therapeutic implications.
    Journal of dermatological science 12/2009; 57(1):2-11. · 3.71 Impact Factor
  • Source
    Article: Juvenile pityriasis rubra pilaris: report of 28 cases in Taiwan.
    [show abstract] [hide abstract]
    ABSTRACT: Pityriasis rubra pilaris (PRP) is a papulosquamous dermatosis uncommon in juveniles. Large-scale studies are limited, especially from Asian countries. We sought to analyze the clinical manifestations of juvenile PRP in Taiwanese patients and compare them with reported series in the literature. The diagnosis of juvenile PRP was made based on clinical-histopathologic correlation. The therapeutic response and disease course were followed up by re-examination of the patients or by telephone. A total of 47 patients were identified, with histopathologic confirmation of the clinical diagnosis of juvenile PRP in 28 cases. A preponderance of Griffiths' type IV PRP (85.7%) rather than type III PRP (14.3%) was found. Palmoplantar hyperkeratosis appeared to be a cardinal feature. In patients with type IV PRP, skin lesions in areas other than the elbows/knees and palms/soles were common. Treatment with systemic acitretin in 6 patients failed to effect a dose- or time-dependent improvement. In contrast with other studies, two thirds of our patients with type III and IV juvenile PRP had a protracted course lasting more than 3 years. This study was a retrospective review. Patient compliance with treatment was frequently poor. Type IV juvenile PRP predominated but our cases showed a wider distribution of skin lesions than is typically described. When children present with an acute onset of diffuse palmoplantar hyperkeratosis, a diagnosis of juvenile PRP should be considered. Because of the divergent clinical manifestations of juvenile PRP in different populations, there is a need to modify and re-evaluate classification systems based on regional differences.
    Journal of the American Academy of Dermatology 10/2008; 59(6):943-8. · 3.99 Impact Factor
  • Article: Giant café-au-lait macule in neurofibromatosis 1: a type 2 segmental manifestation of neurofibromatosis 1?
    [show abstract] [hide abstract]
    ABSTRACT: Type 2 segmental manifestation of autosomal dominant dermatoses refers to pronounced segmental lesions superimposed on the ordinary nonsegmental phenotype, indicating loss of heterozygosity occurring at an early stage of embryogenesis. We describe a 20-year-old Taiwanese woman with typical lesions of neurofibromatosis type 1 (NF1) in the form of characteristic café-au-lait spots, neurofibromas, axillary freckling and Lisch nodules. In addition, a giant garment-like or "bathing-trunk" café-au-lait macule involved the lower half of the trunk, the buttocks, and parts of the thighs, being superimposed on the ordinary smaller spots of NF1. This large café-au-lait macule may be best explained as an example of type 2 segmental NF1. A novel mutation (3009delG) in exon 23 was also identified in this patient, which has not yet been described in sporadic and familial NF1.
    Journal of the American Academy of Dermatology 04/2008; 58(3):493-7. · 3.99 Impact Factor
  • Article: Expression of sex-determining genes in the scalp of men with androgenetic alopecia.
    [show abstract] [hide abstract]
    ABSTRACT: The regulation of the cutaneous steroidogenesis in patients with androgenetic alopecia remains largely unclear. The purpose of this study was to quantify the expression of the sex-determining genes in different scalp areas. Paired scalp specimens from frontal and occipital scalp areas of 10 patients were examined by real-time RT-PCR for mRNA expression and of 40 patients (mean age 34.9 years, range 22-58) by Western blotting for protein analysis. The SOX-9 mRNA was most abundant in the skin, while SF-1 mRNA was sparsely detected. The protein levels of DAX-1, SRY and WT-1 were significantly higher in the bald scalp (p=0.003, 0.004 and 0.03, respectively). Only the SRY expression showed a positive correlation with the baldness severity in Norwood-Hamilton classification (p=0.024). There was no association between patient's age and the protein levels. Immunostaining of SOX-9 was detected in the outer root sheath keratinocytes of hair follicles but not in the dermal papillae. Further study on a larger population, including normal subjects and female patients, is needed to confirm the pathogenic role of sex-determining genes in androgenetic alopecia.
    Dermatology 02/2007; 214(3):199-204. · 2.05 Impact Factor
  • Article: Case of co-morbidity of alopecia areata and pityriasis lichenoides in a five year old boy for two years.
    The Journal of Dermatology 11/2006; 33(10):724-6. · 1.49 Impact Factor
  • Article: Hypersensitivity syndrome and pure red cell aplasia following allopurinol therapy in a patient with chronic kidney disease.
    [show abstract] [hide abstract]
    ABSTRACT: To report a rare case of combined hypersensitivity syndrome and pure red cell aplasia (PRCA) following allopurinol therapy. A 43-year-old woman with underlying mesangioproliferative glomerulonephritis developed fever, generalized morbilliform rash, leukocytosis with marked eosinophilia, and hepatic dysfunction 3 weeks after starting allopurinol therapy (300 mg/day for 3 days followed by 200 mg/day) for hyperuricemia and arthritis. The clinical findings were judged to be a probable drug reaction according to the Naranjo probability scale. The drug-induced hypersensitivity syndrome (DHS) resolved after withdrawal of allopurinol and initiation of systemic corticosteroid therapy. However, there was progressive worsening of anemia with reticulocytopenia; PRCA was suspected. PRCA was judged to be a possible drug reaction according to the Naranjo probability scale. The patient refused blood transfusion and bone marrow biopsy. Recombinant human erythropoietin was initiated in addition to prednisolone 15 mg daily. Eleven days later (approximately 7 wk after allopurinol withdrawal), both the hemoglobin level and reticulocyte count began to rise. The patient consented to a bone marrow study at that time, which confirmed the presence of dysplasia involving only the erythroid lineage. Allopurinol may induce DHS, aplastic anemia, and, in rare instances, PRCA. We report the first case of PRCA concurrent with allopurinol-induced DHS in a patient with chronic kidney disease. Discontinuation of allopurinol is the first step in the treatment of such cases. The slow recovery of PRCA might be partly attributed to her underlying chronic kidney disease. To minimize serious DHS, proper indications for treatment and dosage adjustment should be closely observed when starting allopurinol therapy in patients with chronic kidney disease.
    Annals of Pharmacotherapy 10/2005; 39(9):1552-6. · 2.13 Impact Factor
  • Article: Histopathology of persistent papules and plaques in adult-onset Still's disease.
    [show abstract] [hide abstract]
    ABSTRACT: Persistent plaques and linear pigmentation have been reported as specific skin lesions in some patients with adult-onset Still's disease (AOSD). We sought to characterize the histologic findings of AOSD-associated persistent rash in 11 cases and correlate the histologic findings with the clinical features. From 1988 to 2004, 17 cases fulfilling Yamaguchi's criteria for AOSD in our hospital were reviewed and 11 (65%) manifested persistent papules and plaques. The pathology of 13 biopsy specimens of persistent eruption from 9 patients was reviewed. The 11 patients consisted of 3 men and 8 women with age of onset ranging from 19 to 67 years (average 34.7 years). Evanescent Still's rash was recorded in 9 patients. The persistent rash manifested as pruritic, red, violaceous, or brownish scaly or crusted lichenoid papules and plaques usually widely distributed over the trunk, neck, face, and extensor sides of the extremities. Lesions arranged in a bizarre linear pattern resulting from scratching were noted in some patients. Three patients died of severe disease, systemic complications, or both. The histology of persistent papules and plaques was characterized by: (1) multiple individual necrotic keratinocytes, singly or in aggregates, mainly located in the upper epidermis, including the normal or parakeratotic horny layer; and (2) infiltration of lymphocytes and neutrophils in the papillary and middermis. Other less common findings included basal vacuolar alteration, nuclear dust, and subcorneal or intracorneal pustules. A clinically and pathologically distinct form of persistent lichenoid eruption was commonly observed in our patients with AOSD. The combination of multiple individual necrotic keratinocytes in the upper epidermis and a dermal infiltrate of neutrophils allow for histologic differentiation of this persistent eruption from most other lichenoid and interface dermatitides and may facilitate an earlier diagnosis of AOSD.
    Journal of the American Academy of Dermatology 07/2005; 52(6):1003-8. · 3.99 Impact Factor
  • Article: Patients with a large prostate show a higher prevalence of androgenetic alopecia.
    [show abstract] [hide abstract]
    ABSTRACT: Androgenetic alopecia (AGA) and benign prostatic hyperplasia (BPH) are both androgen-dependent disorders, displaying in situ high levels of dihydrotestosterone with a good therapeutic response to finasteride. Embryological development of both the hair follicle and the prostate depends on mesenchymal-epithelial interaction, which is influenced by the expression of type 2 5alpha-reductase. The aim of this study was to elucidate the association between the size of the prostate gland and the prevalence and severity of AGA. A total of 46 patients age between 56 and 87 years were retrospectively recruited. They fulfilling the clinical diagnosis of BPH defined as (1) prostate volume > 30 cm3, measured by transrectal ultrasound, (2) maximal urine flow rate < 15 ml/s and mean urine flow rate < 10 ml/s, and (3) prostate serum albumin < 10 ng/ml. The control group comprised 34 patients aged between 49 and 81 years with urogenital infection, cystitis or urolithiasis. The expression and severity of AGA were evaluated by dermatologists using modified Norwood/Hamilton classification. Patients with a prostate volume > 30 cm3 had a higher prevalence of AGA than patients with a smaller prostate (< 30 cm3) (83.3% vs 61.3%; P < 0.05). The prostate size, however, did not correlate with the severity of AGA in either group or in the whole patient group. The prevalence of AGA was not significantly different in patients with or without BPH (85.7% vs 70.6%). The prostate was slightly larger among patients with AGA than among those without AGA (mean+/-SD 42.7+/-17.4 vs 35.4+/-14.9 cm3), but this was not statistically significant. There was no significant correlation between the age of onset of AGA and the development of BPH. Our results suggest that a larger prostate is associated with a higher prevalence of AGA. It remains to be seen if long-term use of finasteride in AGA patients will prophylactically lower the incidence of BPH.
    Archives for Dermatological Research 12/2004; 296(6):245-9. · 2.28 Impact Factor
  • Article: Histopathological differential diagnosis of keloid and hypertrophic scar.
    [show abstract] [hide abstract]
    ABSTRACT: Distinguishing hypertrophic scar (HS) from keloid histopathologically is sometimes difficult because thickened hyalinized collagen (keloidal collagen), the hallmark of keloid, is not always detectable and alpha-smooth muscle actin (alpha-SMA), a differentiating marker of HS, is variably expressed in both forms of scar. The aim of this study was to investigate additional distinguishing features to facilitate differentiation between keloid and HS. We compared various histologic features and the expression of alpha-SMA in 40 specimens of keloid and 10 specimens of HS. The features more commonly seen in keloids were: (a) no flattening of the overlying epidermis, (b) no scarring of the papillary dermis, (c) presence of keloidal collagen, (d) absence of prominent vertically oriented blood vessels, (e) presence of prominent disarray of fibrous fascicles/nodules, (f) presence of a tongue-like advancing edge underneath normal-appearing epidermis and papillary dermis, (g) horizontal cellular fibrous band in the upper reticular dermis, and (h) prominent fascia-like fibrous band. The last three features were found in keloid specimens only, including the ones lacking detectable keloidal collagen. Our study confirmed the diagnostic value of keloidal collagen, but it was only found in 55% of keloid specimens. Alpha-SMA expression was found in both HS (70%) and keloid (45%), thus it would not be a differentiating marker. In scars with no detectable keloidal collagen, the presence of the following feature(s) favors the diagnosis of keloid: non-flattened epidermis, non-fibrotic papillary dermis, a tongue-like advancing edge, horizontal cellular fibrous band in the upper reticular dermis, and prominent fascia-like band.
    American Journal of Dermatopathology 11/2004; 26(5):379-84. · 1.20 Impact Factor
  • Article: Acute generalized exanthematous pustulosis caused by celecoxib.
    Chao-Chun Yang, Julia Yu-Yun Lee, Wen-Chieh Chen
    [show abstract] [hide abstract]
    ABSTRACT: Acute generalized exanthematous pustulosis (AGEP) is a rapidly evolving, febrile, widespread, non-follicular pustular eruption mainly provoked by drugs. Celecoxib, a selective cyclooxygenase-2 (COX-2) inhibitor containing a sulfonamide substitute, is now clinically widely used due to its advantage of lower rate of gastrointestinal irritation. We report a case of AGEP in a 61-year-old woman who presented with fever, widespread maculopapules, vesicles, bullae, tiny pustules and leukocytosis soon after the ingestion of celecoxib. The condition resolved rapidly within 10 days. AGEP was diagnosed based on clinical and histopathological findings. Skin patch testing showed positive reaction to 1% celecoxib without cross-reactivity to 1% sulfamethoxazole-trimethoprim.
    Journal of the Formosan Medical Association 08/2004; 103(7):555-7. · 1.13 Impact Factor
  • Article: Folliculitis decalvans associated with Micronychia.
    Dermatology 02/2004; 208(3):227-8. · 2.05 Impact Factor
  • Source
    Article: Expression of peroxisome proliferator-activated receptor and CCAAT/enhancer binding protein transcription factors in cultured human sebocytes.
    [show abstract] [hide abstract]
    ABSTRACT: Lipid synthesis and accumulation represent a major step in sebocyte differentiation and it may be of importance for sebocytes to express two families of transcription factors, CCAAT/enhancer binding proteins (c/EBPs) and peroxisome proliferator-activated receptors (PPARs), which were found to play a crucial role in the differentiation of adipocytes. Using the immortalized human sebaceous gland cell line SZ95 we examined the expression of the molecules before and after treatment with testosterone, 5alpha-dihydrotestosterone, dexamethasone, 17beta-estradiol and genistein, at 6, 12, 24, and 48 h, respectively. Reverse transcription-PCR analysis showed expression of peroxisome proliferator-activated receptors -alpha, -delta, -gamma1, -gamma2 and CCAAT/enhancer binding proteins-alpha, -beta, -gamma-delta in native SZ95 sebocytes. In western blot studies, high levels of CCAAT/enhancer binding proteins-alpha and -beta, and peroxisome proliferator-activated receptors-gamma were expressed at 6, 24, and 12 h, respectively. Immunostaining of the cultured sebocytes showed the CCAAT/enhancer binding proteins-alpha and -beta mainly localized within nuclei, whereas peroxisome proliferator-activated receptors-gamma in the cytoplasm. Strong staining of sebocytes was immunohistochemically revealed in the basal layer of sebaceous glands in human scalp and sebaceous nevus. Genistein down-regulated the expression of CCAAT/enhancer binding proteins-alpha and -beta, and peroxisome proliferator-activated receptors-gamma on the protein level. Treatment with linoleic acid for 48 h induced further differentiation of sebocytes leading to abundant lipid synthesis.
    Journal of Investigative Dermatology 10/2003; 121(3):441-7. · 6.31 Impact Factor
  • Article: Mutation analysis of X-linked hypohidrotic ectodermal dysplasia in a Taiwanese family.
    [show abstract] [hide abstract]
    ABSTRACT: X-linked hypohidrotic ectodermal dysplasia (XLHED, OMIM 305100) is the most common form among the ectodermal dysplasias, a rare group of hereditary diseases characterized by abnormal development of eccrine sweat glands, hair, and teeth. Heterozygous carriers of XLHED often manifest minor or moderate degrees of hypotrichosis, hypodontia, and hypohidrosis. ED1, the gene involved in XLHED, encodes ectodysplasin A, a new member of the tumor necrosis factor family. The majority of mutations in XLHED are missense mutations, but one-fifth are insertion/deletions. In this report, we describe the mutation analysis of a Taiwanese pedigree with XLHED. A 35-bp deletion in exon 5 of the ED1 gene was found in the 3 affected males and in 5 female carriers. Mutation analysis in families with XLHED allows for genetic counseling, prenatal diagnosis, and confirmation of carrier status.
    Journal of the Formosan Medical Association 07/2003; 102(6):412-7. · 1.13 Impact Factor
  • Article: Adult-onset Still's disease with persistent skin eruption and fatal respiratory failure in a Taiwanese woman.
    European journal of dermatology: EJD 16(5):593-4. · 2.53 Impact Factor
  • Article: Febrile ulceronecrotic Mucha-Habermann disease with extensive skin necrosis in intertriginous areas.
    Chao-Chun Yang, Julia Yu-Yun Lee, WenChieh Chen
    [show abstract] [hide abstract]
    ABSTRACT: Febrile ulceronecrotic Mucha-Habermann disease (FUMHD) is a severe variant of pityriasis lichenoides et varioliformis acuta characterized by high fever and papulonecrotic skin lesions. Here we report a case of a 14-year-old boy with typical features of FUMHD and unusual manifestation of extensive skin necrosis in intertriginous regions including axillae, neck, inguinal and antecubital areas. Systemic administration of corticosteroid and erythromycin led to rapid healing of ulcerations without residual scar formation. Review of the literature showed male-predominance and favorable outcome in pediatric cases of FUMHD.
    European journal of dermatology: EJD 13(5):493-6. · 2.53 Impact Factor