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1.
PLoS Pathog ; 15(3): e1007511, 2019 03.
Article in English | MEDLINE | ID: mdl-30893371

ABSTRACT

While much is known about acute infection pathogenesis, the understanding of chronic infections has lagged. Here we sought to identify the genes and functions that mediate fitness of the pathogen Pseudomonas aeruginosa in chronic wound infections, and to better understand the selective environment in wounds. We found that clinical isolates from chronic human wounds were frequently defective in virulence functions and biofilm formation, and that many virulence and biofilm formation genes were not required for bacterial fitness in experimental mouse wounds. In contrast, genes involved in anaerobic growth, some metabolic and energy pathways, and membrane integrity were critical. Consistent with these findings, the fitness characteristics of some wound impaired-mutants could be represented by anaerobic, oxidative, and membrane-stress conditions ex vivo, and more comprehensively by high-density bacterial growth conditions, in the absence of a host. These data shed light on the bacterial functions needed in chronic wound infections, the nature of stresses applied to bacteria at chronic infection sites, and suggest therapeutic targets that might compromise wound infection pathogenesis.


Subject(s)
Cell Proliferation/physiology , Pseudomonas aeruginosa/growth & development , Wound Healing/physiology , Adult , Animals , Bacteria/growth & development , Bacterial Infections/metabolism , Biofilms/growth & development , Disease Models, Animal , Female , Genetic Fitness , Host Microbial Interactions/physiology , Humans , Male , Mice , Pseudomonas Infections , Pseudomonas aeruginosa/metabolism , Pseudomonas aeruginosa/pathogenicity , Virulence/physiology , Wound Infection/metabolism , Wound Infection/microbiology
2.
Wound Repair Regen ; 24(2): 373-83, 2016 03.
Article in English | MEDLINE | ID: mdl-26748963

ABSTRACT

Biofilms have been implicated in delayed wound healing, although the mechanisms by which biofilms impair wound healing are poorly understood. Many species of bacteria produce exotoxins and exoenzymes that may inhibit healing. In addition, oxygen consumption by biofilms and by the responding leukocytes, may impede wound healing by depleting the oxygen that is required for healing. In this study, oxygen microsensors to measure oxygen transects through in vitro cultured biofilms, biofilms formed in vivo within scabs from a diabetic (db/db) mouse wound model, and ex vivo human chronic wound specimens was used. The results showed that oxygen levels within mouse scabs had steep gradients that reached minima ranging from 17 to 72 mmHg on live mice and from 6.4 to 1.1 mmHg on euthanized mice. The oxygen gradients in the mouse scabs were similar to those observed for clinical isolates cultured in vitro and for human ex vivo specimens. To characterize the metabolic activities of the bacteria in the mouse scabs, transcriptomics analyses of Pseudomonas aeruginosa biofilms associated with the db/db mice wounds was performed. The results demonstrated that the bacteria expressed genes for metabolic activities associated with cell growth. Interestingly, the transcriptome results also indicated that the bacteria within the wounds experienced oxygen-limitation stress. Among the bacterial genes that were expressed in vivo were genes associated with the Anr-mediated hypoxia-stress response. Other bacterial stress response genes highly expressed in vivo were genes associated with stationary-phase growth, osmotic stress, and RpoH-mediated heat shock stress. Overall, the results supported the hypothesis that bacterial biofilms in chronic wounds promote chronicity by contributing to the maintenance of localized low oxygen tensions, through their metabolic activities and through their recruitment of cells that consume oxygen for host defensive processes.


Subject(s)
Biofilms/growth & development , Biosensing Techniques , Diabetes Mellitus, Experimental/metabolism , Oxygen/metabolism , Pseudomonas Infections/microbiology , Transcriptome/physiology , Wound Infection/metabolism , Animals , Diabetes Mellitus, Experimental/pathology , Disease Models, Animal , Humans , Mice , Osmotic Pressure , Pseudomonas Infections/pathology , Wound Healing/physiology , Wound Infection/pathology
3.
Wound Repair Regen ; 23(5): 745-52, 2015 Sep.
Article in English | MEDLINE | ID: mdl-26171654

ABSTRACT

Evidence-based ulcer care guidelines detail optimal components of care for treatment of ulcers of different etiologies. We investigated the impact of providing specific evidence-based ulcer treatment components on healing outcomes for lower limb ulcers (LLU) among veterans in the Pacific Northwest. Components of evidence-based ulcer care for venous, arterial, diabetic foot ulcers/neuropathic ulcers were abstracted from medical records. The outcome was ulcer healing. Our analysis assessed the relationship between evidence-based ulcer care by etiology, components of care provided, and healing, while accounting for veteran characteristics. A minority of veterans in all three ulcer-etiology groups received the recommended components of evidence-based care in at least 80% of visits. The likelihood of healing improved when assessment for edema and infection were performed on at least 80% of visits (hazard ratio [HR] = 3.20, p = 0.009 and HR = 3.54, p = 0.006, respectively) in patients with venous ulcers. There was no significant association between frequency of care components provided and healing among patients with arterial ulcers. Among patients with diabetic/neuropathic ulcers, the chance of healing increased 2.5-fold when debridement was performed at 80% of visits (p = 0.03), and doubled when ischemia was assessed at the first visit (p = 0.045). Veterans in the Pacific Northwest did not uniformly receive evidence-based ulcer care. Not all evidence-based ulcer care components were significantly associated with healing. At a minimum, clinicians need to address components of ulcer care associated with improved ulcer healing.


Subject(s)
Compression Bandages , Debridement/methods , Evidence-Based Medicine/methods , Leg Ulcer/therapy , Negative-Pressure Wound Therapy/methods , Veterans , Wound Healing , Aged , Chronic Disease , Female , Humans , Incidence , Leg Ulcer/epidemiology , Male , Northwestern United States/epidemiology , Retrospective Studies , Treatment Outcome
4.
Dermatol Online J ; 19(11): 20409, 2013 Nov 15.
Article in English | MEDLINE | ID: mdl-24314784

ABSTRACT

Cutaneous angiosarcoma of the head and neck is a rare, highly malignant neoplasm; prognosis is heavily influenced by tumor size, resectability, and stage at initial diagnosis. Most patients present with one to several erythematous to violaceous patches, plaques, or nodules. However, the clinical presentation is highly variable and leads to delayed diagnosis. We report cutaneous angiosarcoma in a 43-year-old man who presented with an 11-month history of progressive solid (non-pitting) edema involving his entire face, scalp, eyelids, and neck without characteristic clinical features of cutaneous angiosarcoma. A skin biopsy had shown non-specific findings consistent with solid facial edema or rosacea. Various etiologies were considered but there was no significant improvement after directed medical therapy. Repeat skin biopsies revealed angiosarcoma involving the dermis and sub-cutis. Computed tomography (CT) of the chest showed multiple lung nodules bilaterally and a lytic lesion in the T6 vertebra consistent with metastases. He was treated with single agent chemotherapy (paclitaxel), and had a partial response that restored his ability to open both eyes spontaneously; However, his edema has recently progressed 7 months after diagnosis. This is a rare example of cutaneous angiosarcoma presenting as progressive solid facial edema, which underscores the diverse range of clinical manifestations associated with this neoplasm.


Subject(s)
Edema/etiology , Facial Neoplasms/pathology , Hemangiosarcoma/secondary , Skin Neoplasms/pathology , Adult , Antineoplastic Agents, Phytogenic/therapeutic use , Facial Neoplasms/complications , Facial Neoplasms/drug therapy , Hemangiosarcoma/complications , Hemangiosarcoma/drug therapy , Humans , Lung Neoplasms/secondary , Male , Paclitaxel/therapeutic use , Skin Neoplasms/complications , Skin Neoplasms/drug therapy , Spinal Neoplasms/drug therapy , Spinal Neoplasms/secondary , Thoracic Vertebrae
5.
Wound Repair Regen ; 20(2): 253-61, 2012.
Article in English | MEDLINE | ID: mdl-22332802

ABSTRACT

Bacteria colonizing chronic wounds often exist as biofilms, yet their role in chronic wound pathogenesis remains unclear. Staphylococcus aureus biofilms induce apoptosis in dermal keratinocytes, and given that chronic wound biofilms also colonize dermal tissue, it is important to investigate the effects of bacterial biofilms on dermal fibroblasts. The effects of a predominant wound pathogen, methicillin-resistant S. aureus, on normal, human, dermal fibroblasts were examined in vitro. Cell-culture medium was conditioned with equivalent numbers of either planktonic or biofilm methicillin-resistant S. aureus and then fed to fibroblast cultures. Fibroblast response was evaluated using scratch, viability, and apoptosis assays. The results suggested that fibroblasts experience the same fate when exposed to the soluble products of either planktonic or biofilm methicillin-resistant S. aureus, namely limited migration followed by death. Enzyme-linked immunosorbent assays demonstrated that fibroblast production of cytokines, growth factors, and proteases were differentially affected by planktonic and biofilm-conditioned medium. Planktonic-conditioned medium induced more interleukin-6, interleukin-8, vascular endothelial growth factor, transforming growth factor-ß1, heparin-bound epidermal growth factor, matrix metalloproteinase-1, and metalloproteinase-3 production in fibroblasts than the biofilm-conditioned medium. Biofilm-conditioned medium induced more tumor necrosis factor-α production in fibroblasts compared with planktonic-conditioned medium, and suppressed metalloproteinase-3 production compared with controls.


Subject(s)
Biofilms/growth & development , Fibroblasts/metabolism , Keratinocytes/microbiology , Methicillin-Resistant Staphylococcus aureus/pathogenicity , Plankton/metabolism , Wound Healing , Cells, Cultured , Culture Media, Conditioned , Cytokines/metabolism , Enzyme-Linked Immunosorbent Assay , Fibroblasts/microbiology , Humans , Keratinocytes/metabolism , Plankton/microbiology
6.
Wound Repair Regen ; 20(3): 342-52, 2012.
Article in English | MEDLINE | ID: mdl-22564229

ABSTRACT

Bacterial biofilm has been shown to play a role in delaying wound healing of chronic wounds, a major medical problem that results in significant health care burden. A reproducible animal model could be very valuable for studying the mechanism and management of chronic wounds. Our previous work showed that Pseudomonas aeruginosa (PAO1) biofilm challenge on wounds in diabetic (db/db) mice significantly delayed wound healing. In this wound time course study, we further characterize the bacterial burden, delayed wound healing, and certain aspects of the host inflammatory response in the PAO1 biofilm-challenged db/db mouse model. PAO1 biofilms were transferred onto 2-day-old wounds created on the dorsal surface of db/db mice. Control wounds without biofilm challenge healed by 4 weeks, consistent with previous studies; none of the biofilm-challenged wounds healed by 4 weeks. Of the biofilm-challenged wounds, 64% healed by 6 weeks, and all of the biofilm-challenged wounds healed by 8 weeks. During the wound-healing process, P. aeruginosa was gradually cleared from the wounds while the presence of Staphylococcus aureus (part of the normal mouse skin flora) increased. Scabs from all unhealed wounds contained 10(7) P. aeruginosa, which was 100-fold higher than the counts isolated from wound beds (i.e., 99% of the P. aeruginosa was in the scab). Histology and genetic analysis showed proliferative epidermis, deficient vascularization, and increased inflammatory cytokines. Hypoxia inducible factor expression increased threefold in 4-week wounds. In summary, our study shows that biofilm-challenged wounds typically heal in approximately 6 weeks, at least 2 weeks longer than nonbiofilm-challenged normal wounds. These data suggest that this delayed wound healing model enables the in vivo study of bacterial biofilm responses to host defenses and the effects of biofilms on host wound healing pathways. It may also be used to test antibiofilm strategies for treating chronic wounds.


Subject(s)
Biofilms/growth & development , Diabetes Mellitus, Experimental/microbiology , Pseudomonas Infections/microbiology , Pseudomonas aeruginosa/growth & development , Wound Healing , Animals , Diabetes Mellitus, Experimental/pathology , Male , Mice , Mice, Inbred NOD , Pseudomonas Infections/pathology , Time Factors
7.
BMC Microbiol ; 11: 143, 2011 Jun 21.
Article in English | MEDLINE | ID: mdl-21693040

ABSTRACT

BACKGROUND: Many chronic diseases, such as non-healing wounds are characterized by prolonged inflammation and respond poorly to conventional treatment. Bacterial biofilms are a major impediment to wound healing. Persistent infection of the skin allows the formation of complex bacterial communities termed biofilm. Bacteria living in biofilms are phenotypically distinct from their planktonic counterparts and are orders of magnitude more resistant to antibiotics, host immune response, and environmental stress. Staphylococcus aureus is prevalent in cutaneous infections such as chronic wounds and is an important human pathogen. RESULTS: The impact of S. aureus soluble products in biofilm-conditioned medium (BCM) or in planktonic-conditioned medium (PCM) on human keratinocytes was investigated. Proteomic analysis of BCM and PCM revealed differential protein compositions with PCM containing several enzymes involved in glycolysis. Global gene expression of keratinocytes exposed to biofilm and planktonic S. aureus was analyzed after four hours of exposure. Gene ontology terms associated with responses to bacteria, inflammation, apoptosis, chemotaxis, and signal transduction were enriched in BCM treated keratinocytes. Several transcripts encoding cytokines were also upregulated by BCM after four hours. ELISA analysis of cytokines confirmed microarray results at four hours and revealed that after 24 hours of exposure, S. aureus biofilm induced sustained low level cytokine production compared to near exponential increases of cytokines in planktonic treated keratinocytes. The reduction in cytokines produced by keratinocytes exposed to biofilm was accompanied by suppressed phosphorylation of MAPKs. Chemical inhibition of MAPKs did not drastically reduce cytokine production in BCM-treated keratinocytes suggesting that the majority of cytokine production is mediated through MAPK-independent mechanisms. CONCLUSIONS: Collectively the results indicate that S. aureus biofilms induce a distinct inflammatory response compared to their planktonic counterparts. The differential gene expression and production of inflammatory cytokines by biofilm and planktonic cultures in keratinocytes could have implications for the formation and persistence of chronic wounds. The formation of a biofilm should be considered in any study investigating host response to bacteria.


Subject(s)
Biofilms/growth & development , Cytokines/metabolism , Gene Expression Regulation , Keratinocytes/immunology , Keratinocytes/microbiology , Signal Transduction , Staphylococcus aureus/immunology , Cells, Cultured , Culture Media, Conditioned , Extracellular Signal-Regulated MAP Kinases/metabolism , Gene Expression Profiling , Humans , Phosphorylation , Staphylococcus aureus/growth & development
8.
Am J Dermatopathol ; 33(5): 483-91, 2011 Jul.
Article in English | MEDLINE | ID: mdl-21552102

ABSTRACT

Multicolor flow cytometry (FC) is indispensable for lymphoma diagnosis and classification, but its utility in evaluating skin biopsies for mycosis fungoides (MF) is not well established. We describe the largest series to date of skin biopsies evaluated by FC for MF (n = 33), and we compare the flow cytometric results with the histologic, molecular, and clinical findings. Abnormal T-cell populations were identified by FC in 14 of 18 patients (78%) having histologically confirmed MF and in no patient whose histology was negative or indeterminate for MF (n = 14). One patient had histologic, flow cytometric, and molecular findings compatible with MF, but this patient's clinical course was more suggestive of a drug eruption. Fourteen of 15 abnormal T-cell populations showed definitive aberrant expression of at least 2 surface antigens, including CD2 (47%), CD3 (67%), CD4, CD5 (87%), CD7, and CD45 (67%); most cases (67%) had light scatter properties suggesting increased cell size and/or cytoplasmic complexity. The high specificity of FC suggests that it will be a useful adjunct to routine histology in the evaluation of diagnostic skin biopsies for MF.


Subject(s)
Cell Separation , Flow Cytometry , Mycosis Fungoides/pathology , Skin Neoplasms/pathology , Adult , Aged , Aged, 80 and over , Antigens, CD/biosynthesis , Biopsy , Female , Humans , Immunophenotyping , Male , Middle Aged , Sensitivity and Specificity , T-Lymphocytes/metabolism , T-Lymphocytes/pathology , Young Adult
9.
Wound Repair Regen ; 18(5): 467-77, 2010.
Article in English | MEDLINE | ID: mdl-20731798

ABSTRACT

Chronic wounds are a major clinical problem that lead to considerable morbidity and mortality. We hypothesized that an important factor in the failure of chronic wounds to heal was the presence of microbial biofilm resistant to antibiotics and protected from host defenses. A major difficulty in studying chronic wounds is the absence of suitable animal models. The goal of this study was to create a reproducible chronic wound model in diabetic mice by the application of bacterial biofilm. Six-millimeter punch biopsy wounds were created on the dorsal surface of diabetic (db/db) mice, subsequently challenged with Pseudomonas aeruginosa (PAO1) biofilms 2 days postwounding, and covered with semiocclusive dressings for 2 weeks. Most of the control wounds were epithelialized by 28 days postwounding. In contrast, none of biofilm-challenged wounds were closed. Histological analysis showed extensive inflammatory cell infiltration, tissue necrosis, and epidermal hyperplasia adjacent to challenged wounds-all indicators of an inflammatory nonhealing wound. Quantitative cultures and transmission electron microscopy demonstrated that the majority of bacteria were in the scab above the wound bed rather than in the wound tissue. The model was reproducible, allowed localized cutaneous wound infections without high mortality, and demonstrated delayed wound healing following a biofilm challenge. This model may provide an approach to study the role of microbial biofilms in chronic wounds as well as the effect of specific biofilm therapy on wound healing.


Subject(s)
Biofilms/growth & development , Diabetes Mellitus, Experimental/complications , Pseudomonas Infections/microbiology , Pseudomonas aeruginosa/physiology , Wound Healing/physiology , Wound Infection/microbiology , Animals , Chronic Disease , Female , Follow-Up Studies , Mice , Pilot Projects , Pseudomonas Infections/complications , Pseudomonas Infections/pathology , Time Factors , Wound Infection/complications , Wound Infection/pathology
10.
J Cutan Pathol ; 37(1): 8-14, 2010 Jan.
Article in English | MEDLINE | ID: mdl-19602072

ABSTRACT

BACKGROUND: Algorithmic scoring approaches for evaluating early cases of mycosis fungoides (MF) provide a degree of diagnostic standardization. At the UWMC, biopsies from clinically concerning cases for MF are individually reviewed by a panel of pathologists and an average score is assigned to each biopsy reflecting the degree of suspicion for a diagnosis of MF; however, such an approach may not be practical outside of an academic center. METHODS: 78 cases characterized in our institution, with the diagnosis confirmed by clinicopathologic correlation/clinical follow-up were evaluated with two different algorithms, based entirely on histologic evaluation (Guitart algorithm) and partial implementation of the ISCL algorithm evaluating histology, immunohistochemistry and T-cell clonality. RESULTS: A receiver operating characteristic curve comparing the results of the two approaches in early MF cases showed no statistical difference between the areas under the two curves. Increased stages of MF showed variable loss of T-cell antigens by immunohistochemistry and higher rates of detectable clonality. CONCLUSION: We could not document a statistically significant advantage of adding ancillary immunohistochemical and molecular testing to careful histologic evaluation in the workup of suspected cases of early MF. A systemic approach to histologic diagnosis by a single pathologist correlated favorably to the MF panel diagnosis.


Subject(s)
Algorithms , Mycosis Fungoides/diagnosis , Biomarkers, Tumor/metabolism , Clone Cells , Humans , Immunohistochemistry , Mycosis Fungoides/metabolism , Neoplasm Staging , ROC Curve , Reproducibility of Results , Retrospective Studies , T-Lymphocytes/pathology
11.
J Histochem Cytochem ; 57(2): 123-42, 2009 Feb.
Article in English | MEDLINE | ID: mdl-18824633

ABSTRACT

Subsequent to wounding, keratinocytes must quickly restore barrier function. In vitro wound models have served to elucidate mechanisms of epithelial closure and key roles for integrins alpha6beta4 and alpha3beta1. To extrapolate in vitro data to in vivo human tissues, we used ultrathin cryomicrotomy to simultaneously observe tissue ultrastructure and immunogold localization in unwounded skin and acute human cutaneous wounds. Localization of the beta4 integrin subunit in unwounded skin shows dominant hemidesmosomal association and minor basal keratinocyte lateral filopodic cell-cell expression. After wounding, beta4 dominantly localized to cytokeratin-rich regions (trailing edge hemidesmosomes) and minor association with lamellipodia (leading edge). beta4 colocalizes with alpha3 within filopodia juxtaposed to wound matrix, and increased concentrations of beta4 were found in cytoplasmic vesicles within basal keratinocytes of the migrating tongue. alpha3 integrin subunit dominantly localized to filopodia within basal keratinocyte lateral cell-cell interfaces in unwounded skin and both cell-cell and cell-matrix filopodic interactions in wounded skin. This study indicates that beta4 interacts with the extracellular environment through both stable and transient interactions and may be managed through a different endosomal trafficking pathway than alpha3. alpha3 integrin, despite its ability to respond to alternate ligands after wounding, does so through a single structure, the filopodia.


Subject(s)
Integrin alpha3/metabolism , Integrin beta4/metabolism , Skin/injuries , Skin/metabolism , Cell Movement , Cytoplasm/metabolism , Epithelium/metabolism , Epithelium/ultrastructure , Frozen Sections , Hemidesmosomes/metabolism , Humans , Immunohistochemistry , Keratins/metabolism , Protein Subunits/metabolism , Pseudopodia/metabolism , Skin/ultrastructure
12.
J Cell Biol ; 167(3): 555-62, 2004 Nov 08.
Article in English | MEDLINE | ID: mdl-15534005

ABSTRACT

Phosphorylation of connexin43 (Cx43) on serine368 (S368) has been shown to decrease gap junctional communication via a reduction in unitary channel conductance. Examination of phosphoserine368 (pS368) in normal human skin tissue using a phosphorylation site-specific antibody showed relatively even distribution throughout the epidermal layers. However, 24 h after wounding, but not at 6 or 72 h, pS368 levels were dramatically increased in basal keratinocytes and essentially lost from suprabasal layers adjacent to the wound (i.e., within 200 microm of it). Scratch wounding of primary human keratinocytes caused a protein kinase C (PKC)-dependent increase in pS368 in cells adjacent to the scratch, with a time course similar to that found in the wounds. Keratinocytes at the edge of the scratch also transferred dye much less efficiently at 24 h, in a manner dependent on PKC. However, keratinocyte migration to fill the scratch required early (within <6 h) gap junctional communication. Our evidence indicates that PKC-dependent phosphorylation of Cx43 at S368 creates dynamic communication compartments that can temporally and spatially regulate wound healing.


Subject(s)
Cell Communication , Connexin 43/metabolism , Gap Junctions/physiology , Protein Kinase C/physiology , Wound Healing , Cell Movement , Gap Junctions/metabolism , Humans , Keratinocytes/enzymology , Keratinocytes/pathology , Keratinocytes/physiology , Kinetics , Phosphorylation , Phosphoserine/analysis , Protein Kinase C/metabolism , Skin/chemistry , Skin/cytology
13.
Wound Repair Regen ; 17(5): 690-9, 2009.
Article in English | MEDLINE | ID: mdl-19671124

ABSTRACT

Bacteria colonizing chronic wounds are believed to exist as polymicrobial, biofilm communities; however, there are few studies demonstrating the role of biofilms in chronic wound pathogenesis. This study establishes a novel method for studying the effect of biofilms on the cell types involved in wound healing. Cocultures of Staphylococcus aureus biofilms and human keratinocytes (HK) were created by initially growing S. aureus biofilms on tissue culture inserts then transferring the inserts to existing HK cultures. Biofilm-conditioned medium (BCM) was prepared by culturing the insert-supported biofilm in cell culture medium. As a control planktonic-conditioned medium (PCM) was also prepared. Biofilm, BCM, and PCM were used in migration, cell viability, and apoptosis assays. Changes in HK morphology were followed by brightfield and confocal microscopy. After only 3 hours exposure to BCM, but not PCM, HK formed dendrite-like extensions and displayed reduced viability. After 9 hours, there was an increase in apoptosis (p< or =0.0004). At 24 hours, biofilm-, BCM-, and PCM-exposed HK all exhibited reduced scratch closure (p< or =0.0001). The results demonstrated that soluble products of both S. aureus planktonic cells and biofilms inhibit scratch closure. Furthermore, S. aureus biofilms significantly reduced HK viability and significantly increased HK apoptosis compared with planktonic S. aureus.


Subject(s)
Apoptosis , Biofilms , Cell Survival , Keratinocytes/pathology , Staphylococcal Infections/physiopathology , Staphylococcus aureus , Chronic Disease , Humans , Staphylococcal Infections/microbiology , Tissue Culture Techniques
14.
J Drugs Dermatol ; 8(9): 870-2, 2009 Sep.
Article in English | MEDLINE | ID: mdl-19746680

ABSTRACT

Autoimmune phenomena are common in both hepatitis C infection and interferon alfa treatment; however, the development of antiphospholipid syndrome is rare. This article reports the case of a patient who developed antiphospholipid syndrome in addition to cutaneous sarcoidosis in the setting of pegylated interferon alfa and ribavirin treatment for hepatitis C.


Subject(s)
Antiphospholipid Syndrome/chemically induced , Antiviral Agents/adverse effects , Sarcoidosis/chemically induced , Antiviral Agents/therapeutic use , Female , Hepatitis C, Chronic/drug therapy , Humans , Interferon-alpha/adverse effects , Interferon-alpha/therapeutic use , Middle Aged , Polyethylene Glycols/chemistry , Ribavirin/adverse effects , Ribavirin/therapeutic use
15.
J Histochem Cytochem ; 56(7): 687-96, 2008 Jul.
Article in English | MEDLINE | ID: mdl-18413645

ABSTRACT

Epithelialization of normal acute wounds occurs by an orderly series of events whereby keratinocytes migrate, proliferate, and differentiate to restore barrier function. The keratinocytes in the epidermis of chronic ulcers fail to execute this series of events. To better understand the epithelial dynamics of chronic ulcers, we used immunohistochemistry to evaluate proliferation, differentiation, adhesion, and migration in keratinocytes along the margin of chronic ulcers from patients with diabetes mellitus. We compared these features with keratinocytes from the migrating epithelial tongues of acute incisional and excisional wounds from normal volunteers. Keratinocytes at the chronic ulcer edge are highly proliferative (Ki67 proliferation marker), have an activated phenotype (K16), do not stain for keratins involved in epidermal differentiation (K10 and K2), and show a reduced expression of LM-3A32 (uncleaved, precursor of the alpha3 chain of laminin 5), a key molecule present on migrating epithelium. In contrast, keratinocytes in normal acute wound migrating epithelium do not express the proliferation marker Ki67 but do express K10, K2, and LM-3A32. A better understanding of molecular mechanisms involved in keratinocyte migration may lead to molecular targets for therapies for impaired wound healing.


Subject(s)
Diabetic Foot/pathology , Keratinocytes/pathology , Keratinocytes/physiology , Skin/injuries , Skin/pathology , Aged , Arm , Cell Adhesion , Cell Differentiation , Cell Movement , Cell Proliferation , Chronic Disease , Female , Humans , Immunohistochemistry , In Situ Hybridization , Leg , Male , Wound Healing
16.
J Am Acad Dermatol ; 59(2): 346-9, 2008 Aug.
Article in English | MEDLINE | ID: mdl-18485525

ABSTRACT

Scleromyxedema is notable for significant morbidity and mortality. A generalized eruption of waxy papules in the absence of thyroid disease with histologic findings of mucin deposition, increased fibroblast proliferation, and fibrosis are the characteristic features of scleromyxedema. We report a case of scleromyxedema that, on histology, was associated with interstitial granuloma annulare-like features. Based on our literature review, this is a rare presentation of this disease. Familiarity with the histologic aspects of scleromyxedema, as described in this report, can help to improve the accuracy of this diagnosis, particularly in atypical presentations.


Subject(s)
Granuloma Annulare/diagnosis , Scleromyxedema/diagnosis , Diagnosis, Differential , Granuloma Annulare/complications , Granuloma Annulare/pathology , Humans , Male , Middle Aged , Pruritus/etiology , Scleromyxedema/complications , Scleromyxedema/pathology
17.
J Cutan Pathol ; 35 Suppl 1: 50-4, 2008 Oct.
Article in English | MEDLINE | ID: mdl-18840155

ABSTRACT

The development of juvenile xanthogranuloma (JXG) as a sequel to langerhans cell histiocytosis (LCH) treated with chemotherapy is rare and the hypothesis is intriguing. This is a case of a 19-year-old woman who presented with progressive development of tan-red papules on the axilla and eyelids over a 1.5-year time span. A biopsy of an axillary lesion showed a prominent dermal infiltrate of foamy histiocytoid cells with occasional Touton-type multinucleate giant cells, consistent with JXG. Three years later, the patient presented with additional similar papules on the axilla and vulva as well as a painful mass in the pelvic bone and diabetes insipidus with an associated pituitary mass. An iliac crest bone biopsy showed an eosinophil-rich infiltrate admixed with histiocytoid cells with reniform nuclei, which expressed S100 and CD1a, consistent with a diagnosis of LCH. Nonetheless, an additional axillary papule was once again consistent with JXG, with negative reaction for S100 and CD1a with no Birbeck granules by electron microscopy. This case is unique by the co-existing presentation of multiple cutaneous JXG lesions and internally confined LCH lesions without an apparently associated chemotherapy, corroborating the concept that JXG and LCH may share a common histogenesis.


Subject(s)
Histiocytosis, Langerhans-Cell/complications , Histiocytosis, Langerhans-Cell/pathology , Xanthogranuloma, Juvenile/complications , Xanthogranuloma, Juvenile/pathology , Adult , Anti-Inflammatory Agents/administration & dosage , Antineoplastic Agents/administration & dosage , Clobetasol/administration & dosage , Cytarabine/administration & dosage , Female , Histiocytosis, Langerhans-Cell/drug therapy , Humans , Immunosuppressive Agents/administration & dosage , Methotrexate/administration & dosage , Prednisone/administration & dosage , Vincristine/administration & dosage , Xanthogranuloma, Juvenile/drug therapy
18.
J Cutan Pathol ; 35(6): 579-84, 2008 Jun.
Article in English | MEDLINE | ID: mdl-18005171

ABSTRACT

CD4+/CD56+ hematodermic neoplasm (HN), formerly known as a blastic natural killer (NK) cell lymphoma, is a rare subtype of a cutaneous dendritic cell neoplasm notable for highly aggressive behavior. The characteristic features are: expression of the T-helper/inducer cell marker CD4 and the NK-cell marker CD56 in the absence of other T cell or NK-cell specific markers. In particular, CD3 (surface or cytoplasmic) and CD2 are not expressed. Although T-cell receptor (TCR) genes are generally reported to be in a germline configuration, we present an unusual variant of a CD4+/CD56+ HN with a clonal rearrangement of TCR genes. This feature of a CD4+/CD56+ HN has been only rarely reported. Recognition of the presence of clonal TCR gene rearrangements in a small subset of CD4+/CD56+ HN is important to avoid misdiagnosis of this entity as an unusual variant of a cutaneous T-cell lymphoma.


Subject(s)
CD4 Antigens/analysis , CD56 Antigen/analysis , Gene Rearrangement, gamma-Chain T-Cell Antigen Receptor/genetics , Lymphoma, T-Cell, Cutaneous/pathology , Skin Neoplasms/pathology , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Biomarkers, Tumor/analysis , Cyclophosphamide/therapeutic use , DNA, Neoplasm/genetics , Dexamethasone/therapeutic use , Doxorubicin/therapeutic use , Flow Cytometry , Humans , Immunohistochemistry , Lymphoma, T-Cell, Cutaneous/chemistry , Lymphoma, T-Cell, Cutaneous/drug therapy , Lymphoma, T-Cell, Cutaneous/genetics , Male , Middle Aged , Skin Neoplasms/chemistry , Skin Neoplasms/drug therapy , Skin Neoplasms/genetics , Vincristine/therapeutic use
19.
J Dermatol Sci ; 48(3): 177-88, 2007 Dec.
Article in English | MEDLINE | ID: mdl-17719208

ABSTRACT

BACKGROUND: Keratinocyte migration is essential for wound healing and diabetic wound keratinocytes migrate poorly. Keratinocyte migration and anchorage appears to be mediated by laminin-332 (LM-332). Impaired diabetic wound healing may be due to defective LM-332 mediated keratinocyte migration. OBJECTIVE: To evaluate LM-332 expression in diabetic (db/db) and control (db/-) mice and to test LM-332 wound healing effects when applied to mouse wounds. METHODS: LM-332 expression in mouse wounds was evaluated using immunohistochemistry. LM-332 wound healing effects were evaluated by directly applying soluble LM-332, a LM-332 biomaterial, or a control to mouse wounds. Percent wound closure and histology score, based on healing extent, were measured. RESULTS: Precursor LM-332 expression was markedly reduced in db/db when compared to db/- mice. In vitro, soluble LM-332 and LM-332 biomaterial demonstrated significant keratinocyte adhesion. In vivo, soluble LM-332 treated wounds had the highest histology score, but significant differences were not found between wound treatments (p>0.05). No differences in percentage wound closure between treatment and control wounds were found (p>0.05). CONCLUSION: The db/db wounds express less precursor LM-332 when compared to db/-. However, LM-332 application did not improve db/db wound healing. LM-332 purified from keratinocytes was primarily physiologically cleaved LM-332 and may not regulate keratinocyte migration. Application of precursor LM-332 rather than cleaved LM-332 may be necessary to improve wound healing, but this isoform is not currently available in quantities sufficient for testing.


Subject(s)
Cell Adhesion Molecules/therapeutic use , Diabetes Complications/drug therapy , Wounds and Injuries/drug therapy , Administration, Topical , Animals , Basement Membrane/metabolism , Basement Membrane/pathology , Cell Adhesion Molecules/administration & dosage , Cell Adhesion Molecules/metabolism , Cell Movement/drug effects , Cell Movement/physiology , Collagen/metabolism , Diabetes Complications/metabolism , Diabetes Complications/pathology , Integrins/metabolism , Keratinocytes/metabolism , Keratinocytes/pathology , Keratinocytes/physiology , Male , Mice , Mice, Inbred C57BL , Mice, Inbred NOD , Mice, Mutant Strains , Wound Healing/drug effects , Wounds and Injuries/metabolism , Wounds and Injuries/pathology , Kalinin
20.
J Biomed Opt ; 11(6): 064002, 2006.
Article in English | MEDLINE | ID: mdl-17212525

ABSTRACT

Ultrahigh-resolution optical coherence tomography (OCT) was used for noninvasive in vivo evaluation of the wound healing process. Cutaneous wounds were induced by 2.5-mm diameter full-thickness punch biopsies on the dorsal surface of seven mice. OCT imaging was performed to assess the structural characteristics associated with the healing process. The OCT results were compared to corresponding histology. Two automated quantitative analysis routines were implemented to identify the dermal-epidermal junction and segment the OCT images. Hallmarks of cutaneous wound healing such as wound size, epidermal migration, dermal-epidermal junction formation, and differences in wound composition were readily identified on the OCT images. Blister formation was also observed. Preliminary findings suggest OCT is a viable tool to noninvasively monitor wound healing in vivo.


Subject(s)
Artificial Intelligence , Image Enhancement/methods , Image Interpretation, Computer-Assisted/methods , Skin/injuries , Skin/ultrastructure , Wound Healing , Wounds, Penetrating/pathology , Algorithms , Animals , Feasibility Studies , Male , Mice , Pattern Recognition, Automated/methods , Reproducibility of Results , Sensitivity and Specificity , Subtraction Technique
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