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Mark R Pittelkow

Publications and source records attributed to Mark R Pittelkow.

At least 19 recordsLinked to original sources
PubMed2007

Early cutaneous gene transcription changes in adult atopic dermatitis and potential clinical implications.

Atopic dermatitis (AD) is a common pruritic dermatitis with macroscopically non-lesional skin that is often abnormal. Therefore, we used high-density oligonucleotide arrays to identify cutaneous gene transcription changes associated with early AD inflammation as potential disease control targets. Skin biopsy specimens analysed included normal skin from five healthy non-atopic adults and both minimally lesional skin and nearby or contralateral non-lesional skin from six adult AD patients. Data were analysed on an individual gene basis and to identify biologically relevant gene networks. Transcription levels of selected genes were also analysed by quantitative PCR. Differential transcription occurring early in AD skin was indicated for (i) individual genes such as C-C chemokine ligand (CCL)18, CCL13, and interferon-alpha2 (IFNalpha2), (ii) genes associated with peroxisome proliferator-activated receptor (PPAR)alpha- and PPARgamma-regulated transcription, and possibly for (iii) immunoglobulin J-chain and heavy chain isotype transcripts. These data suggest that local changes in immunoglobulin-associated transcription may favour IgE over secretory immunoglobulin (multimeric IgM and IgA) expression in AD skin. Decreased PPAR activity appears common to both AD and psoriasis, and reduced cutaneous IFNalpha2 transcription also appears characteristic of AD. Identification of these genes and pathways will direct future research towards controlling AD.

Adult↗
PubMed2006

Calciphylaxis: natural history, risk factor analysis, and outcome.

BACKGROUND: Calciphylaxis is characterized by ischemic cutaneous ulceration, high mortality, and ineffective treatment. METHODS: We conducted a retrospective study of 64 patients with calciphylaxis (including 49 dialysis patients age- and sex-matched to 98 dialysis controls). RESULTS: The estimated 1-year survival rate of calciphylaxis was 45.8%. Risk factors for calciphylaxis included obesity, liver disease, systemic corticosteroid use, calcium-phosphate product more than 70 mg(2)/dL(2), and serum aluminum greater than 25 ng/mL. Survival rates were similar for 16 patients who received parathyroidectomy and 47 who did not. An estimated 1-year survival rate of 61.6% was observed for 17 patients receiving surgical debridement compared with 27.4% for the 46 who did not (P = .008). LIMITATIONS: The study was limited by its retrospective design and there was no control group for the 15 nondialysis cases. CONCLUSIONS: Calciphylaxis is multifactorial and usually fatal. Prevention of calciphylaxis may include correction of risk factors identified in this study. Surgical debridement was associated with improved survival, but parathyroidectomy was not.

Adult↗
PubMed2006

Up-regulation of transient receptor potential canonical 1 (TRPC1) following sarco(endo)plasmic reticulum Ca2+ ATPase 2 gene silencing promotes cell survival: a potential role for TRPC1 in Darier's disease.

The mechanism(s) involved in regulation of store operated calcium entry in Darier's disease (DD) is not known. We investigated the distribution and function of transient receptor potential canonical (TRPC) in epidermal skin cells. DD patients demonstrated up-regulation of TRPC1, but not TRPC3, in the squamous layers. Ca2+ influx was significantly higher in keratinocytes obtained from DD patients and showed enhanced proliferation compared with normal keratinocytes. Similar up-regulation of TRPC1 was also detected in epidermal layers of SERCA2+/- mice. HaCaT cells expressed TRPC1 in the plasma membrane. Expression of sarco(endo)plasmic reticulum Ca2+ ATPase (SERCA)2 small interfering RNA (siRNA) in HaCaT cells increased TRPC1 levels and thapsigargin-stimulated Ca2+ influx, which was blocked by store-operated calcium entry inhibitors. Thapsigargin-stimulated intracellular Ca2+ release was decreased in DD cells. DD keratinocytes exhibited increased cell survival upon thapsigargin treatment. Alternatively, overexpression of TRPC1 or SERCA2-siRNA in HaCaT cells demonstrated resistance to thapsigargin-induced apoptosis. These effects were dependent on external Ca2+ and activation of nuclear factor-kappaB. Isotretinoin reduced Ca2+ entry in HaCaT cells and decreased survival of HaCaT and DD keratinocytes. These findings put forward a novel consequence of compromised SERCA2 function in DD wherein up-regulation of TRPC1 augments cell proliferation and restrict apoptosis. We suggest that the anti-apoptotic effect of TRPC1 could potentially contribute to abnormal keratosis in DD.

Animals↗
PubMed2006

Expression profiling of UVB response in melanocytes identifies a set of p53-target genes.

Epidermal melanocytes execute specific physiological programs in response to UV radiation (UVR) at the cutaneous interface. Many melanocytic responses, including increased dendrite formation, enhanced melanogenesis/melanization, and cell cycle arrest impact the ability of melanocytes to survive and to attenuate the UVR insult. Although some of the molecules that underlie these UVR programs are known, a coherent view of UVR-induced transcriptional changes is lacking. Using primary melanocyte cultures, we assessed for UVR-mediated alterations in over 47,000 transcripts using Affymetrix Human Genome U133 Plus 2.0 microarrays. From the 100 most statistically robust changes in transcript level, there were 84 genes that were suppressed >2.0-fold by UVR; among these transcripts, the identities of 48 of these genes were known. Similarly, there were 99 genes that were induced >2.0-fold by UVR; the identity of 57 of these genes were known. We then subjected these top 100 changes to the Ingenuity Pathway analysis program and identified a group of p53 targets including the cell cycle regulator CDKN1A (p21CIP), the WNT pathway regulator DKK1 (dickkopf homolog 1), the receptor tyrosine kinase EPHA2, growth factor GDF15, ferrodoxin reductase (FDXR), p53-inducible protein TP53I3, transcription factor ATF3, DNA repair enzyme DDB2, and the beta-adrenergic receptor ADBR2. These genes were also found to be consistently elevated by UVR in six independent melanocyte lines, although there were interindividual variations in magnitude. WWOX, whose protein product interacts and regulates p53 and p73, was found to be consistently suppressed by UVR. There was also a subgroup of neurite/axonal developmental genes that were altered in response to UVR, suggesting that melanocytic and neuronal arborization may share similar mechanisms. When compared to melanomas, the basal levels of many of these p53-responsive genes were greatly dysregulated. Three genes--CDKN1A, DDB2 and ADRB2--exhibited a trend towards loss of expression in melanomas thereby raising the possibility of a linked role in tumorigenesis. These expression data provide a global view of UVR-induced changes in melanocytes and, more importantly, generate novel hypotheses regarding melanocyte physiology.

Cell Line, Tumor↗
PubMed2006

Extensive acrochordons and pancreatic islet-cell tumors in tuberous sclerosis associated with TSC2 mutations.

Acrochordons are frequently encountered benign skin lesions that may occasionally represent underlying pathology. Pancreatic islet-cell tumors are rare neoplasms and few cases have been described in patients with tuberous sclerosis complex (TSC). A 39-year-old man presenting in acute renal failure was referred to us for further diagnostic evaluation of coincidentally noted dysmorphic features. Physical examination revealed over 1,000 acrochordons in addition to findings meeting criteria for TSC. The diagnosis was confirmed by disclosure of mutation in the TSC2 gene. Further evaluation revealed pancreatic islet cell tumors. Acrochordons are a common skin lesion, but when presenting in an atypical manner or unusual number may be a sign of TSC and underlying occult pathology thereby warranting evaluation of TSC2. Additionally, mutations in TSC2 gene may be a risk factor for developing pancreatic islet-cell tumors.

Adenoma, Islet Cell↗
PubMed2006

Livedoid vasculopathy: further evidence for procoagulant pathogenesis.

OBJECTIVE: To further characterize the clinical and pathologic features, disease associations, and laboratory abnormalities of livedoid vasculopathy. DESIGN: Retrospective study of patients identified from our institutional database from January 1, 1990, to December 31, 2000. SETTING: Tertiary care institution. Patients Forty-five patients with biopsy-proved livedoid vasculopathy. MAIN OUTCOME MEASURES: Clinical presentation, histopathologic diagnosis, results of testing for coagulation abnormalities, and assessment of vascular status. RESULTS: Thirty-two patients (71.1%) were female (mean age, 45 years; age range, 10-85 years). Bilateral lower extremity disease occurred in 36 patients (80.0%), ulceration in 31 (68.9%), and atrophie blanche in 32 (71.1%). In patients tested, transcutaneous oximetry measurements were decreased in 20 (74.1%) of 27, and factor V Leiden mutation (heterozygous) was noted in 2 (22.2%) of 9, decreased activity for protein C or protein S in 2 (13.3%) of 15, prothrombin G20210A gene mutation in 1 (8.3%) of 12, and lupus anticoagulant in 5 (17.9%) of 28. Anticardiolipin antibodies were present in 8 (28.6%) of 28 patients, and elevated homocysteine levels in 3 (14.3%) of 21. Intraluminal thrombosis was observed in 44 (97.8%) of 45 skin biopsy specimens. Direct immunofluorescence disclosed multiple vascular conjugates in 31 (86.1%) of 36 biopsy specimens. CONCLUSIONS: Livedoid vasculopathy was predominantly bilateral, affected the lower extremities, and was associated with ulceration and atrophie blanche. Histologic evidence of intraluminal thrombosis was observed in almost all biopsy specimens reviewed. Laboratory testing revealed numerous heterogeneous coagulation abnormalities, providing further evidence of procoagulant mechanisms.

Adolescent↗
PubMed2006

Cutaneous complications of intravesical treatments for bladder cancer: granulomatous inflammation of the penis following BCG therapy and penile gangrene following mitomycin therapy.

Transitional cell carcinoma of the bladder is frequently treated with intravesical injection of immunotherapeutic (eg, BCG) or chemotherapeutic (eg, mitomycin C) agents. The aim of this study was to report cutaneous complications of intravesical therapy in 2 patients with transitional cell carcinoma of the bladder. A 69-year-old man had an ulceration at the base of the penis and papules involving the glans penis 1 month after injection of intravesical BCG. Biopsy findings showed granulomatous inflammation with foci of dermal necrosis suggestive of a BCG-related granulomatous reaction. The second patient was a 73-year-old man with penile gangrene. Erythema involving his penis and perineum had developed within 24 hours after intravesical administration of mitomycin C, which spilled onto his perineum during catheter removal. The resulting penile gangrene required penectomy 3 months after the injection. Mitomycin C patch testing showed a clear allergic contact reaction. Dermatologists should be aware of these potential cutaneous complications.

Administration, Intravesical↗
PubMed2006

Adrenergic and cholinergic control in the biology of epidermis: physiological and clinical significance.

The presence of an autocrine adrenergic and cholinergic intra/intercellular signal transduction network in the human epidermis contributes significantly to homeostatic and compensatory responses regulating vital functions in keratinocytes and melanocytes. The ligands produced control autocrine and paracrine loops to initiate responses through cognate receptors expressed within the same or adjacent cells. The epidermal adrenergic signal controls calcium homeostasis, cell growth, differentiation, motility, and pigmentation via the beta2 and alpha1 adrenoceptors. The cholinergic system is highly complex comprising both nicotinic and muscarinic receptors with multiple subtypes and this system plays an important role in keratinocyte cell cycle progression, differentiation, directional migration, adhesion, and apoptotic secretion. Moreover, lymphocytes also express adrenergic and cholinergic receptors. Both types of signal transduction receptors are coupled to classical intracellular second messenger pathways, including cAMP-, cGMP-, and calcium-mediated downstream responses. To date, it has been recognized that several dermatoses such as psoriasis, atopic dermatitis, Mal de Meleda, vitiligo, palmoplantar pustulosis, and pemphigus may be mediated, in part, by the non-neuronal adrenergic/cholinergic systems. A detailed understanding of the physiology and pathophysiology of the adrenergic/cholinergic network in the skin could offer the development of specific drugs for novel treatment modalities.

Animals↗
PubMed2006

Paraneoplastic autoimmune multiorgan syndrome: review of the literature and support for a cytotoxic role in pathogenesis.

Paraneoplastic autoimmune multiorgan syndrome (PAMS), first described as paraneoplastic pemphigus in 1990, is an autoimmune blistering disease associated with neoplasia. Patients with this rare disorder have severe blistering and painful erosions of the oral cavity and various other cutaneous findings ranging from classic pemphigus vulgaris-like erosions to targetoid lesions resembling erythema multiforme and papular to more confluent lichenoid eruptions. This syndrome involves multiple organ systems, and its high rate of mortality often stems from constrictive bronchiolitis obliterans. The histologic findings are as diverse as the clinical presentation, often making diagnosis difficult initially. Immunodermatologic and serologic laboratory findings typically establish the diagnosis. These results can be confirmed with immunoprecipitation profiling of specific molecular weight protein markers. The proposed pathogenesis of PAMS continues to evolve, and recent reports implicate the involvement of cell-mediated, cytotoxic immunity, in addition to humoral autoantibodies. This review characterizes and summarizes the clinical, pathologic, and immunohistologic features of PAMS and outlines the possible role of cytotoxic T lymphocytes in the pathogenesis of this syndrome.

Autoimmune Diseases↗
PubMed2006

Peptide vaccination of patients with metastatic melanoma: improved clinical outcome in patients demonstrating effective immunization.

OBJECTIVES: Therapeutic peptide vaccines for melanoma continue to only demonstrate anecdotal success. We set out to evaluate the impact of low-dose GM-CSF emulsified in Montanide ISA-51 on the immunogenicity of HLA-A2 restricted melanoma differentiation antigen peptide vaccines (MART-1, gp100 and tyrosinase) administered in separate subcutaneous injections. METHODS: We conducted a randomized phase II clinical trial of HLA-A2+ patients with metastatic melanoma that were immunized every 3 weeks with one of the following vaccine preparations: (A) peptides + Montanide ISA-51; (B) peptides + Montanide ISA-51 + GM-CSF (10 microg); (C) peptides + Montanide ISA-51 + GM-CSF (50 microg). Immunization efficacy was determined by quantification of vaccine specific tetramer positive cytotoxic T cells in peripheral blood. Global assessment of immune competence was ascertained using DTH testing to common recall antigens as well as peripheral blood immunophenotyping. RESULTS: Twenty-five eligible patients were equally distributed across all 3 treatment groups. Only 9 patients demonstrated evidence of immunization. Most commonly, immune response was achieved to the gp100 peptide. The addition of low-dose GM-CSF did not impact immunization efficacy. DTH reactivity to Candida appeared predictive of successful immunization. Successful immunization with the peptide vaccines was associated with improved clinical outcomes. CONCLUSIONS: The addition of low dose GM-CSF to peptide vaccines did not enhance immunogenicity. Higher doses of GM-CSF may be needed to achieve this effect and this is a testable hypothesis. Likewise, better patient selection based on immunologic status (DTH reactivity) may be helpful to better understand the clinical impact of therapeutic cancer vaccines.

Adjuvants, Immunologic↗
PubMed2006

A comparison of morphologic features, flow cytometry, TCR-Vbeta analysis, and TCR-PCR in qualitative and quantitative assessment of peripheral blood involvement by Sézary syndrome.

The strengths and weaknesses of various laboratory methods for peripheral blood (PB) Sézary cell quantitation have not been compared rigorously. In this study, manual Sézary cell counting, qualitative and quantitative flow cytometry, T-cell receptor (TCR) Vbeta flow cytometry, and TCR polymerase chain reaction were performed on PB specimens from 11 patients with Sézary syndrome (SS), 9 with reactive erythroderma, 6 with mycosis fungoides, and 11 healthy control subjects. These methods identified neoplastic cells in more than 90% of SS cases. The diagnostic specificities of these tests varied; they were enhanced by applying criteria proposed by the International Society for Cutaneous Lymphoma. Comparison of sequentially analyzed specimens from 6 patients with SS revealed that although the absolute number of clonal cells was reduced, in some cases, these cells still constituted the vast majority of the CD4+ T-cell subset, suggesting that quantitative subset analysis might be sufficient to monitor changes in the PB tumor burden.

Adult↗
PubMed2006

Plasmapheresis for refractory urticarial vasculitis in a patient with B-cell chronic lymphocytic leukemia.

BACKGROUND: Urticarial vasculitis is a form of cutaneous leukocytoclastic vasculitis clinically characterized by persistent and often painful urticarial lesions. Numerous systemic diseases have been associated with urticarial vasculitis, including certain hematologic disorders. This distinctive form of cutaneous necrotizing vasculitis can be resistant to standard therapeutic modalities, necessitating more aggressive intervention. METHODS: We report a case of refractory urticarial vasculitis developing in association with B-cell chronic lymphocytic leukemia in a 46-year-old man. We also reviewed the literature to identify other cases of urticarial vasculitis managed with this therapeutic modality. RESULTS: The disease progressively improved during 6 treatments with plasmapheresis (plasma exchange). In the additional cases identified in the literature, plasmapheresis was generally effective and well tolerated. CONCLUSION: On the basis of these findings, we propose that plasmapheresis be considered a treatment option for refractory urticarial vasculitis.

Antineoplastic Agents, Alkylating↗
PubMed2005

Bexarotene treatment of late-stage mycosis fungoides and Sézary syndrome: development of extracutaneous lymphoma in 6 patients.

Bexarotene is a retinoid drug that is approved for the treatment of cutaneous T-cell lymphoma. We report 6 cases in which the initiation of bexarotene therapy for cutaneous T-cell lymphoma was temporally associated with the progression of internal disease despite improvement in cutaneous signs and symptoms. It is possible that bexarotene contributed to this progression. Although bexarotene therapy may alleviate symptoms and signs of cutaneous T-cell lymphoma, careful surveillance of lymph nodes and solid organs during treatment is advised.

Adult↗
PubMed2005

Increased metastasis and mortality from cutaneous squamous cell carcinoma in patients with chronic lymphocytic leukemia.

In patients with chronic lymphocytic leukemia, squamous cell carcinoma behaves aggressively. Our purpose was to compare squamous cell carcinoma metastasis and mortality between patients with chronic lymphocytic leukemia and control subjects. Medical records were assessed retrospectively for 28 patients with chronic lymphocytic leukemia who underwent surgical excision of cutaneous squamous cell carcinoma and for 56 matched control subjects. The rate of metastasis and mortality from cutaneous squamous cell carcinoma were determined on a per-patient basis. Three of 28 patients with chronic lymphocytic leukemia had metastasis and died of metastatic disease. No metastases or deaths occurred among the 56 control subjects. Compared with control subjects, chronic lymphocytic leukemia patients with cutaneous squamous cell carcinoma were more likely to have metastasis (P = .0031) and die of metastasis (P = .0033). No significant association was detected between metastasis and history of chemotherapy administration for chronic lymphocytic leukemia. Among patients with chronic lymphocytic leukemia, surveillance for skin cancer and a decreased threshold for biopsy of suspect lesions are warranted.

Aged↗