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1.
C5a and C5a des Arg are potent complement-derived mediators that bind receptors on peripheral blood leukocytes and tissue-specific cellular elements to elicit and amplify inflammatory and immunomodulatory reactions. To study the interactions of C5a and C5a des Arg with these cells, fluorescein conjugates of these ligands were prepared by a new technique and their binding to monocytes, neutrophils, platelets, and endothelial cells was studied with flow cytometry. Fluoresceinated C5a produced neutrophil myeloperoxidase release and chemotaxis and also bound rabbit anti-C5a antibody much like native anaphylatoxin; likewise, fluoresceinated C5a des Arg demonstrated retention of biologic and antigenic activities. Both fluorescein-conjugated C5a and C5a des Arg bound to monocytes and neutrophils in a concentration-dependent, saturable, and homogeneous manner, but 10- to 15-fold higher concentrations of C5a des Arg were required to attain saturable binding of these leukocytes. Ligand binding was specifically inhibited by native purified human C5a in a concentration-dependent manner, while it was unaffected by C3a or N-formyl-methionyl-leucyl-phenylalanine-lysine. There was no evidence of a C5a receptor-negative subpopulation of monocytes or neutrophils. Moreover, comparative binding experiments with leukocytes from multiple normal volunteers showed that a greater percentage of monocytes than neutrophils bound C5a at less than saturable concentrations of ligand (P less than 0.05, 0.5 to 5.0 nM). A representative half-maximal binding of fluorescein-conjugated C5a (C5a des Arg) binding to monocytes and neutrophils was 1.2 nM (30 nM) and 2.6 nM (68 nM), respectively. In contrast, fluorescein-conjugated C5a did not specifically bind to human platelets or umbilical vein endothelial cells.  相似文献   

2.
Spitzoid melanoma is a subtype of melanoma that, clinically and histologically, resembles a Spitz nevus. Clinically, spitzoid melanomas usually evolve from amelanotic nodular lesions, growing to 1 cm or more in diameter. They often remain clinically undiagnosed because of their wide variety of clinical appearances and a lack of pigmentation. Distinguishing a Spitz nevus from a spitzoid melanoma can be extremely difficult. Features that favor the diagnosis of a spitzoid melanoma are asymmetrical shape, diameter greater than 1 cm, a lesion with a deep invasive component, and a high degree of cytologic atypia. There have been only rare reports in the literature of the presence of giant cells in malignant melanoma, and the presence of these cells may result in its misdiagnosis as a histiocytic tumor. We present a case of spitzoid melanoma on the right ankle of a 22-year-old-woman.  相似文献   

3.
Chagas disease is an endemic zoonosis caused by a protozoan agent called Trypanosoma cruzi. It is mainly transmitted by a hematophagous vector, and less frequently by blood transfusion, transplacental and solid organ transplant. In most cases, primary infection is not diagnosed and the disease progresses to a chronic phase. Immunosuppressed patients are a vulnerable population that may present an acute, atypical and severe reactivation of the chronic form of this disease. We hereby report a case of a female patient, who received a renal transplant with immunosuppressive treatment, who was diagnosed with a chagasic hypodermitis secondary to an acute reactivation of a chronic phase of this disease. We describe the clinical features, epidemiological and histopathological findings, treatment and course.  相似文献   

4.
5.
Abstract: Trichothiodystrophy is characterized by sparse, short, sulfur-deflclent hair. Numerous symptom complexes have been described in which the hair abnormaiity represents a constant feature. We report a boy with trichothiodystrophy, ichthyotic skin changes, onychodystrophy, chronic neutropenia, osteoscierosis, hypothyroidism, nystagmus, growth and mentai retardation, and microcephaiy, who developed a progressive encephalopathy with ataxia and optic atrophy at 2.5 years of age. in addition to a deficient cystine ievei identified on a hair sampie, a disturbance in the composition of other amino acids was present. Ai-though features were reminiscent of osteoscierosis, ichthyosis, brittie hair due to trichothiodystrophy, impaired inteliigence, decreased fertiiity, and short stature (SIBIDS) and couid represent a variant of this disorder, findings in our patient may refiect a new trichothiodystrophy symptom compiex that carries a poor prognosis for survivai beyond chiidhood.  相似文献   

6.
The proliferative nodule is a lesion that develops within a congenital nevus. It is usually small (less than 5 mm), sometimes multiple, with a slow growth rate, and has a black or dark brown, smooth, shiny surface. It usually involutes spontaneously. We report a newborn infant who, at birth, had a giant congenital nevus with a nodular, ulcerative, hemorrhagic lesion within it. Physical and neurologic examinations were normal. Radiologic studies at birth and subsequently were normal. A fragment of the lesion was biopsied and histologic findings were compatible with a diagnosis of proliferative nodule in a giant congenital nevus. The rest of the nodule regressed spontaneously after 4 months.  相似文献   

7.
To investigate the structure, function, and control of CD1a, we have cloned a 1.6-kbp cDNA which encodes the expressed CD1a protein and includes untranslated 5' and 3' sequences and the poly-A tail. As the protein recognized by the monoclonal antibody OKT6, CD1a is a useful marker for Langerhans cells (LC). CD1a is found on these cells and on thymocytes, suggesting an important immunologic role for this molecule. We constructed a cDNA library in lambda gt10 using mRNA from MOLT-4, a cell line that expresses the CD1a surface antigen. We then screened the library with an oligonucleotide synthesized according to a known partial sequence for CD1a, and subcloned the cDNA and its restriction fragments into pGEM for sequencing and probe production. Based on this sequence the CD1a protein is predicted to consist of three extracellular domains (alpha 1-3), a hydrophobic transmembrane region, and a cytoplasmic tail. DNA 5' to the alpha 1 region may undergo alternative exon splicing. There is high sequence identity between the beta-2 microglobulin binding region of MHC I molecules and CD1a. The secondary structure predicted for CD1a is very similar to the actual structure of HLA-A2, a classical MHC I molecule. The similarity includes the beta pleated sheets and alpha helices which form the antigen binding groove of the alpha-1 and alpha-2 domains. The homology predicted between CD1a and HLA-A2 in these regions appears to exist on the level of secondary structure despite low primary nucleotide and amino acid sequence identity. The structural data and probes we have developed should facilitate studies of the function of CD1a as well as novel investigations of LC.  相似文献   

8.
Systemic lupus erythematosus (SLE) is a multisystem disorder with a diverse spectrum of clinical abnormality. Despite advances in our understanding of the disease, the aetiology and outcome remains unknown. We describe a 13-year-old boy who presented with paronychia, mouth ulcers and associated neutropenia. Appropriate investigations including a bone-marrow biopsy revealed a shift to the left, and in the absence of any other immunological abnormalities, a diagnosis of idiopathic neutropenia was made. The patient was successfully treated with granulocyte colony-stimulating factor but subsequently re-presented during the winter months with a purpuric facial eruption affecting his cheeks and ears. On histological examination of a biopsy taken from the ear, a microvascular thrombosis was seen. Laboratory investigations were positive for anticardiolipin antibodies, neutropenia and antinuclear antibodies (ANA), suggesting a diagnosis of juvenile (J)JSLE with antiphospholipid syndrome. This is an unusual presentation of SLE in a prepubertal white boy, with a malar and helical vasculopathy as a novel cutaneous presentation of JSLE.  相似文献   

9.
Onychomatricoma (OM) is an uncommon benign tumor clinically characterized by a thickened yellowish nail with transverse over curvature. A pigmented variant has recently been described. Histologically, the diagnosis requires 3 prerequisites: (1) a fibroepithelial tumor consisting of 2 portions: the proximal zone (under the proximal nailfold, characterized by deep epithelial invaginations and a fibrillary and fibrocytic stroma), whereas the distal zone (corresponding to the lunula) presents with multiple digitations along its connective tissue axes; (2) a matricial tumor typified by a thick keratogenous zone; and (3) a thick nail plate, perforated by cavities. We describe a case that appears clinically identical to a pigmented OM, but with histologic malignant patterns. Because histologic features were consistent with Bowen's disease, we ruled out a malignant OM. We report a new variant of Bowen's disease presenting as OM, and this observation underlines the necessity for a histologic assessment of all forms of OM, especially those associated with a pigmented band (a sign sometimes observed in Bowen's disease).  相似文献   

10.
BACKGROUND: Moderate xerotic eczema, characterized by stratum corneum desquamation, erythema, and pruritis is a common condition that can be induced or worsened by skin cleansing. Traditional dermatologic therapy includes the use of emollients, medium or high potency topical corticosteroids, and a change in bathing habits. OBJECTIVE: To investigate the effect of two cleansing systems: a synthetic detergent bar soap applied with a cotton washcloth and a petrolatum-delivering body wash applied with a polyethylene puff as part of a topical treatment approach to moderate xerotic eczema. METHOD: Sixty patients with moderate xerotic eczema were enrolled in a 4-week investigator-blinded study. Half were randomly treated with a strong topical corticosteroid cream (0.05% fluocinonide) and a traditional cleansing system consisting of a synthetic detergent bar soap applied with a washcloth. The remaining patients were treated with a weaker, medium strength topical corticosteroid cream (0.1% triamcinolone acetonide) and a novel cleansing system consisting of a petrolatum-delivering body wash applied with a polyethylene puff. Dermatologist investigator evaluations and patient self-assessments were conducted at baseline, 2 weeks, and 4 weeks. RESULTS: Patients using the novel petrolatum-delivering body wash and polyethylene puff cleansing system and the lower potency corticosteroid cream demonstrated significantly greater clinical improvement than those patients using the traditional cleansing system of a synthetic detergent beauty bar and washcloth system and the higher potency corticosteroid cream after both 2 and 4 weeks of treatment. CONCLUSION: The cleansing system of a petrolatum-delivering body wash delivered by a polyethylene puff may be useful as a cleanser for patients with moderate xerotic eczema.  相似文献   

11.
We performed an exploratory study to evaluate 2 self-administered questionnaires assessing hand dermatitis and to investigate a possible exposure-response relation between dermal exposure to semi-synthetic metal working fluids (SMWF) and dermatitis. In a cross-sectional survey on dermatitis, a symptom-based questionnaire and a picture-based skin-screening list were applied in 80 SMWF-exposed workers and 67 referents. To evaluate accuracy of the questionnaires, 47 subjects were examined by a dermatologist. Dermal exposure levels to SMWF were assessed on the hands, forearms, and face with an observational method that was validated with a fluorescent-tracer method. The symptom-based questionnaire had a relatively high sensitivity (0.86) but moderate specificity (0.64), the skin-screening list had a low sensitivity (0.36) and a relatively high specificity (0.84). The skin-screening list seemed to represent the more severe cases of dermatitis and showed a significant relation to exposure, for dermatitis on hands, forearms, or face. In epidemiological surveys where workers are not seen by a dermatologist, the skin-screening list seems to be more appropriate to detect cases of dermatitis, as its higher specificity results in less false positives. Alternatively, it would be preferable to apply the symptom-based questionnaire; workers with symptoms should be seen by a dermatologist to identify false positives.  相似文献   

12.
Autoimmune lymphoproliferative syndrome is a disorder due to a defect of lymphocyte apoptosis, whose clinical manifestations consist of hyperplasia of lymphoid tissues and autoimmune diseases. We report on a 26-month-old child who presented with frequent eruptions of weals and angioedema without any apparent triggering factor, who subsequently developed an erythematopapular rash with a histological pattern of a lymphoplasmacellular infiltrate. Familial anamnesis revealed a history of lymphoadenomegaly and massive spleen and liver enlargement in her sister. Functional and molecular analysis led to a diagnosis of type 1a autoimmune lymphoproliferative syndrome. Immunophenotyping of the cutaneous lesion revealed the presence of an inflammatory infiltrate with a considerably high number of Langerhans cells. Cutaneous features such as urticaria, angioedema and vasculitis in children with a personal and familial history of hyperplasia of lymphoid tissues may be a presenting sign of a systemic disease, such as autoimmune lymphoproliferative syndrome.  相似文献   

13.
OBJECTIVES: To determine the attitudes of male and female patients to the use of chaperones during genital examination within a sexually transmitted diseases clinic. STUDY DESIGN: An anonymous, self-completed questionnaire was administered to patients attending the Melbourne Sexual Health Centre, Australia, between September and October 2006. RESULTS: The participation rate among male and female patients was 60% (166 of 276) and 73% (153 of 210), respectively. Among male patients, only 7.3% and 6.0% expressed a desire for a chaperone when being examined by a male and female practitioner, respectively. Among female patients, 26.8% desired a chaperone if they were going to be examined by a male practitioner when compared with 5.5% for a female practitioner (P <0.001). Around one-third of male and female patients indicated they would feel uncomfortable having a chaperone present and this did not vary by the sex of the practitioner (P >0.48). For female patients being examined by a male practitioner, the desire for a chaperone was associated with having had a previous cervical smear (odds ratio, OR = 0.35, 95% CI: 0.12-0.98, P = 0.04) and feeling comfortable about the presence of a chaperone present (OR = 28.9; 95% CI: 11.1-75.0; P <0.001), but not age (P = 0.16) or previous genital examination (OR = 0.55, 95% CI: 0.21-1.45, P = 0.2). CONCLUSIONS: In a sexual health setting, female patients undergoing genital examination by a male clinician should be asked whether they would like a chaperone to be present.  相似文献   

14.
Abstract:  Bullous pemphigoid (BP) is a disease typical of the elderly, and rare in children. With appropriate therapy, the clinical course is usually self-limited. We report on a 5-month-old boy with a severe BP, unresponsive to systemic corticosteroids, intravenous immunoglobulins, dapsone, and cyclosporine A. There is growing evidence for rituximab as a treatment option in refractory autoimmune bullous diseases also in children. We saw a marked improvement in skin lesions within a couple of days after the first dose of rituximab, and blisters disappeared. Monitoring of CD19-positive cells showed a fast decrease to almost zero and a slow recovery within 4 weeks. At this time, new blisters appeared and another dose of rituximab was given. After the second dose of rituximab a long-lasting effect without development of new bullae was observed.  相似文献   

15.
Flank organs of hamster are useful for studying androgen-dependent growth of hair follicles and sebaceous glands. To elucidate the mechanism of gene expression regulated by androgen, we constructed a cDNA library from flank organs of male hamsters and screened by a differential hybridization method using cDNA probes from normal and castrated males. We isolated a cDNA clone, termed FAR-17a, whose expression was found to be highly sensitive to androgen. FAR-17a mRNA of 1.8 kb was reduced after castration and reappeared after testosterone treatments. Among several tissues examined, FAR-17a gene was expressed at a high level in flank organ and a low level in testis and earlobe. FAR-17a probe detected a few fragments in genomic DNA of hamster, mouse, suncus, pig, and human, suggesting that this gene is phylogenetically conserved. The sequence of FAR-17a cDNA predicts a protein of 231 amino acids (27,216 daltons) having basic properties. The deduced protein has no significant homologies to proteins previously described.  相似文献   

16.
We report a case of a 27-year-old woman with a nonpigmented lesion on the right scalp. Histological examination showed a malignant nodular neoplasm with 2 distinct but intimately admixed components: a malignant melanoma with a spindle component and an unusual glandular component. Immunohistochemical studies demonstrated epithelial differentiation on the basis of cytokeratin (CAM5.2 and AE1/AE3) expression in the glandular component and melanocytic differentiation (HMB-45, PNL2, MITF, and S-100) of the spindle cell component. A single melanocytic marker (MITF) was expressed in both components, raising the possibility of dual differentiation in a single tumor, rather than the alternative considerations of a collision tumor or a reactive pseudoepitheliomatous hyperplasia with eccrine duct lumen formation within a melanoma. This unusual tumor with both melanocytic and epithelial components may represent a true melanocarcinoma, which becomes a plausible consideration, in view of melanoma plasticity and recent experimental evidence and speculation about the role of stem cells in melanoma.  相似文献   

17.
Leukoderma in association with congenital melanocytic nevi is a rare phenomenon; nevertheless several reports have been published in the literature. We present a 15-year-old boy born with a pigmented lesion on the lower and upper eyelid diagnosed as a congenital divided nevus of the eyelid. At the age of 13, he developed a depigmented area around the nevus and was diagnosed at first as having a halo nevus in a congenital nevus. Over the next two years, an area of depigmentation appeared around the contralateral eye. At the present time, the patient has bilateral periocular depigmentation. Congenital divided nevus of the eyelid is a rare lesion, and no reports have been published to date of depigmentation in association with this lesion. Our patient presented with depigmentation around the nevus as in a halo nevus phenomenon, although at the present time, the depigmented area has a symmetric periocular distribution, and therefore can be labeled as periocular vitiligo associated with a congenital divided nevus.  相似文献   

18.
P53 is rarely mutated in cutaneous T-cell lymphoma (CTCL) and is therefore a promising target for innovative therapeutic approaches. Nutlin-3a is an inhibitor of MDM2 (human homolog of murine double minute 2), which disrupts its interaction with p53, leading to the stabilization and activation of p53. To investigate the potential therapeutic use of nutlin-3a in CTCL, we screened CTCL lines Hut-78, SeAx, MyLa2000, Mac1, and Mac2a by measuring p53 levels after nutlin-3a treatment. In MyLa2000, Mac1, and Mac2a, we observed the increase in p53, indicating the fully functional p53. In the remaining cell lines, P53 mutation analysis identified a homozygous nonsense mutation (R196Stop in Hut-78) and a homozygous missense mutation (G245S in SeAx). In MyLa2000, Mac1, and Mac2a carrying wild-type P53, nutlin-3a induced apoptosis and senescence demonstrated by permanent G0/G1 cell-cycle block and expression of the senescence-associated β-galactosidase. This effect was abolished in cells in which p53 was silenced by small interfering RNA. Sézary cells lack functional p53 and were resistant to nutlin-3a. However, nutlin-3a potentiated the efficacy of conventional chemotherapeutics not only in cells with intact p53 but also in Hut-78, SeAx, and Sézary cells. Thus, targeting p53 by nutlin-3a may constitute a therapeutic approach in CTCL because of increased apoptosis and senescence of tumor cells.  相似文献   

19.
Dermatoscopic white circles, seen with both non-polarized and polarized dermatoscopy, are a known clue to actinic keratosis in a flat lesion and invasive squamous cell carcinoma in a raised lesion. We have not discovered a previous published example of this clue in a melanoma. We present a case report of a 70-year-old Australian male with a pigmented superficial spreading melanoma on the face, Breslow thickness 1 mm, with dermatoscopic white circles displayed with both polarized and non-polarized dermatoscopy, and with dermatopathological correlation.  相似文献   

20.
A 4‐year‐old girl presented with sparse, brittle hair on her entire scalp and keratosis pilaris on the nape of her neck. Subtle microscopic and macroscopic diagnostic features presented a challenge for physicians. Only repeated, optimized light microscopy revealed the diagnosis of monilethrix, a rare genetic hair shaft disorder with a variable phenotypic expression and inheritance pattern. We provide a short overview of methods that maximize the diagnostic yield in a clinical setting and of light microscopy to reach a rapid and accurate diagnosis in difficult cases. We conclude with essential learning points, including a link to assistance with hair microscopy from a tertiary center.  相似文献   

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