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Background: Lower heart rate (HR) increases during exercise and slower HR recovery (HRR) after exercise are markers of worse autonomic function that may be associated with risk of acute respiratory events (ARE)., Methods: Data from 6-min walk testing (6MWT) in COPDGene were used to calculate the chronotropic index (CI) [(HR immediately post 6MWT - resting HR)/((220 - age) - resting HR)] and HRR at 1 min after 6MWT completion. We used zero-inflated negative binomial regression to test associations of CI and HRR with rates of any ARE (requiring steroids and/or antibiotics) and severe ARE (requiring emergency department visit or hospitalization), among all participants and in spirometry subgroups (normal, chronic obstructive pulmonary disease [COPD], and preserved ratio with impaired spirometry)., Results: Among 4,484 participants, mean follow-up time was 4.1 years, and 1,966 had COPD. Among all participants, CI-6MWT was not associated with rate of any ARE [adjusted incidence rate ratio (aIRR) 0.98 (0.95-1.01)], but higher CI-6MWT was associated with lower rate of severe ARE [0.95 (0.92-0.99)]. Higher HRR was associated with a lower rate of both any ARE [0.97 (0.95-0.99)] and severe ARE [0.95 (0.92-0.98)]. Results were similar in the COPD spirometry subgroup., Conclusion: Heart rate measures derived from 6MWT tests may have utility in predicting risk of acute respiratory events and COPD exacerbations., (Published by Elsevier Ltd.)

Purpose: Meaningful participation in research for both faculty and residents is generally viewed to be an essential component of residency training. To better understand best practices in residency research, the authors conducted a survey among Internal Medicine (IM) Residency Programs with experience in research., Methods: Phone interviews were conducted with a convenience sample of Residency Program Directors (PDs). Survey responses were analyzed across the following domains: size and makeup of the residency and research programs, resources for research, role of the PD/research director (RD), profile of trainees doing research, curriculum description, scope of research, role of mentors, career choices and determinants of success., Results: Fifteen programs were included in the study. Across these programs, approximately two-thirds of residents were involved in research during their training . Eighty percent of the programs required an application for residents to engage in research. Ninety-two percent of the programs had a RD but only 58% had a formal research curriculum. Clinical research projects were the most common types of research. On average, two-thirds of residents involved in research submitted abstracts to regional and/or national meetings. The factor most frequently associated with resident research success was an effective faculty research mentor., Conclusions: Research success during residency is multifactorial. The authors propose that having a robust structure for research that is led by a residency RD, and the presence of effective mentors and strong administrative support are critical for success., (Published by Elsevier Inc.)

Background: The practice patterns for adjuvant therapies for stage I seminoma are rapidly evolving, and surveillance is currently preferred. How these recommendations have affected contemporary practice in an equal-access US population is unknown., Materials and Methods: A total of 436 men diagnosed with clinical stage IA-IB seminoma from 2001 to 2011 were identified in the Automated Central Tumor Registry (ACTUR). The ACTUR is the cancer registry system for the Department of Defense. Logistic regression models analyzed the association between patient characteristics and adjuvant therapy. Overall and recurrence-free survival were determined from Kaplan-Meier analysis., Results: The use of adjuvant radiotherapy in this population decreased significantly from 2001 to 2011. In 2001, 83.9% of patients received radiotherapy compared with only 24.0% in 2011. During that period, a concomitant increase occurred in the use of chemotherapy from 0% to 38.0%. A later year of diagnosis was significantly associated with a greater rate of receiving chemotherapy relative to radiotherapy (P < .001 for 2006-2011 vs. 2001-2005; relative rate ratio, 19.3; 95% confidence interval [CI], 8.04-46.13). A later year of diagnosis was not significantly associated with the receipt of surveillance (P = .412 for 2006-2011 vs. 2001-2005; odds ratio, 0.83; 95% CI, 0.54-1.29). Black race or age was not significantly associated with adjuvant therapy. With a median follow-up period of 4.7 years, the 5-year overall and recurrence-free survival rates were 98.0% and 77.0%, respectively., Conclusion: The use of adjuvant radiotherapy has been replaced by chemotherapy for clinical stage I testicular seminoma in an equal-access system. The lack of an increase in active surveillance in our cohort might represent overtreatment of the population., (Published by Elsevier Inc.)

Peri-urban floodplains are an important interface between developed land and the aquatic environment and may act as a source or sink for contaminants moving from urban areas towards surface water courses. With increasing pressure from urban development the functioning of floodplains is coming under greater scrutiny. A number of peri-urban sites have been found to be populated with legacy landfills which could potentially cause pollution of adjacent river bodies. Here, a peri-urban floodplain adjoining the city of Oxford, UK, with the River Thames has been investigated over a period of three years through repeated sampling of groundwaters from existing and specially constructed piezometers. A nearby landfill has been found to have imprinted a strong signal on the groundwater with particularly high concentrations of ammonium and generally low concentrations of nitrate and dissolved oxygen. An intensive study of nitrogen dynamics through the use of N-species chemistry, nitrogen isotopes and dissolved nitrous oxide reveals that there is little or no denitrification in the majority of the main landfill plume, and neither is the ammonium significantly retarded by sorption to the aquifer sediments. A simple model has determined the flux of total nitrogen and ammonium from the landfill, through the floodplain and into the river. Over an 8 km reach of the river, which has a number of other legacy landfills, it is estimated that 27.5 tonnes of ammonium may be delivered to the river annually. Although this is a relatively small contribution to the total river nitrogen, it may represent up to 15% of the ammonium loading at the study site and over the length of the reach could increase in-stream concentrations by nearly 40%. Catchment management plans that encompass floodplains in the peri-urban environment need to take into account the likely risk to groundwater and surface water quality that these environments pose., (Crown Copyright © 2014. Published by Elsevier B.V. All rights reserved.)

Background: A newly discovered DNA virus, transfusion-transmitted virus (TTV), has been implicated as a cause of post-transfusion hepatitis. We investigated the frequency of TTV viraemia in UK blood donors, and the extent to which TTV contaminates blood products such as factor VIII and IX clotting factors. We also investigated the possible aetiological role of TTV in cryptogenic fulminant hepatic failure (FHF)., Methods: We extracted DNA from plasma of blood donors and patients with FHF, and from blood products (factor VIII and IX clotting-factor concentrates, immunoglobulin preparations). We detected TTV by PCR using primers from a conserved region in the TTV genome., Findings: TTV viraemia was detected in 19 (1.9%) of 1000 non-remunerated regular blood donors. Infection occurred more frequently in older donors (mean age 53 years), compared with the age prolife of donors infected with hepatitis C virus and other parenterally-transmitted viruses. TTV contamination was found in ten (56%) of 18 batches of factor VIII and IX concentrate manufactured from such non-remunerated donors, and in seven (44%) of 16 batches of commercially available products. Whereas solvent or detergent treatment had little effect on the detection of TTV in factor VIII and IX by PCR, this virucidal step seemed to inactivate TTV infectivity. TTV infection was detected in four (19%) of 21 patients with FHF; in three cases, infection was detected at the onset of disease and could thus not be excluded from its aetiology., Interpretation: TTV viraemia is frequent in the blood-donor population, and transmission of TTV through transfusion of blood components may have occurred extensively. Clinical assessment of infected donors and recipients of blood and blood products, and assessment of TTV's aetiological role in hepatic and extra-hepatic disease, are urgently needed.

E-selectin is an endothelial adhesion molecule that binds carbohydrate epitopes on leukocytes and has been implicated in a potential pathway of tumor metastasis. Keratinocyte cell lines express similar carbohydrate epitopes, one of which, sialyl Lewis X (SL-X) is a ligand for E-selectin and is also expressed by squamous cell carcinomas (SCC) in situ. The functional role of keratinocyte selectin ligands was investigated using a soluble E-selectin chimaeric protein (pE-sel-Ig) containing pig lectin-like and epidermal growth factor-like domains fused to human IgG. After incubation of keratinocyte cell lines (A431 and SVK14) and normal keratinocytes with pE-sel Ig, binding was quantified by flow cytometry. Frozen sections of SCC were overlaid with pE-sel Ig and binding was visualized immunoenzymatically. Immunolabeling was undertaken using monoclonal antibodies (CSLEX-1 and HECA-452), which label E-selectin ligands including sialyl Lewis X. E-selectin bound strongly to A431 and SVK14 cells; the degree of binding paralleled staining intensity with CSLEX-1 antibody. HECA-452 antibody stained A431 cells strongly but SVK14 cells only weakly. Normal keratinocytes and normal epidermis did not express CSLEX-1 or HECA-452 antigens or bind E-selectin. Serial sections of SCC revealed close correlation between fusion protein binding and antibody staining. Antibody pretreatment of tumor sections with CSLEX-1 blocked fusion protein binding, whereas HECA-452 antibody only slightly reduced fusion protein binding. pE-sel Ig pretreated with YT11.1 antibody failed to bind to A431 or SVK14 cells or to SCC. These studies provide functional evidence that SL-X/E-selectin pathways may be important in SCC metastasis and that A431 and SVK14 cells provide a good model to investigate these mechanisms.

Recent evidence suggests that interactions between endothelial selectins and tumor surface selectin ligands may be of importance in cancer metastasis. To investigate the role of such mechanisms in cutaneous tumors, whole skin biopsies were examined immunohistochemically for a variety of selectin ligands including sialyl-Lewis-X, sialyl-Lewis-A (S-Le(a)), sulfatides, and CD15. In 12 of 12 squamous cell carcinomas (SCCs), there was expression of sialyl-Lewis-X and CD15, but no tumor expressed S-Le(a). Occasional keratinocytes in eight of 12 SCCs expressed sulfatides. All selectin ligands were absent on keratinocytes in basal cell carcinomas (BCCs, n = 8) and normal skin (n = 8), with the exception of one BCC that expressed S-Le(a). E-selectin was not present in normal skin, but was strongly expressed by dermal endothelium in both SCC and BCC. Keratinocyte cell lines A431, HaCaT, and SVK14 were investigated by flow cytometry, which demonstrated sialyl-Lewis-X and S-Le(a) expression by all three, whereas normal human keratinocytes did not express these molecules. These findings suggest a potential role for selectin-mediated events in early and late metastasis, and differential expression of these ligands by BCC and SCC may explain the relatively low metastatic potential of the former.

Recombinant human interferon-gamma was administered intradermally (10 micrograms in 0.1 ml) to healthy adult human volunteers from day 1 to day 3, and epidermal cell proliferation was measured on whole skin biopsies at day 6. Three independent parameters were assessed, namely, a) epidermal keratin-16 expression, b) keratinocyte proliferating cell nuclear antigen expression, and c) keratinocyte silver nucleolar organizer region counts. Significantly increased scores for each parameter were observed after interferon-gamma injection (P < 0.01 in each case) compared to site-matched controls. Keratin-16 expression was confined to suprabasal epidermis, whereas proliferating cell nuclear antigen and silver nucleolar organizer region counts were particularly elevated in the basal epidermis. Taken together with previous findings, these studies indicate both proinflammatory and growth regulatory roles for interferon-gamma in human skin. These data are likely to be of particular importance to pathophysiological mechanisms of psoriasis and related cutaneous inflammatory diseases.

Endothelial leukocyte adhesion molecule-1 (ELAM-1), vascular cell adhesion molecule-1 (VCAM-1), and intercellular adhesion molecule-1 (ICAM-1) are cytokine-regulated cell-surface leukocyte adhesion molecules. We have investigated the in vivo kinetics and pattern of expression of these adhesion molecules in relation to tissue accumulation of leukocytes in the photodermatosis, polymorphic light eruption (PMLE), which is characterized by dense perivascular leukocytic infiltration. Immunohistology was performed on biopsies taken at varying time points from PMLE lesions induced in 11 subjects by suberythemal solar simulated irradiation. Vascular endothelial ELAM-1 expression was first observed at 5 h, maximal at 24 to 72 h, and remained elevated at 6 d. VCAM-1, minimally expressed in control skin, was induced above background levels on endothelium and some perivascular cells after 24 h and maintained at 6 d. Endothelial cell ICAM-1 expression was increased above control levels at 72 h and 6 d. Keratinocyte ICAM-1 expression, most marked overlying areas of dermal leukocytic infiltration, began at 5 h and was strong at 72 h and 6 d. In addition to lymphocytes, significant numbers of neutrophils but not eosinophils were detected in the dermal leukocytic infiltrate that appeared at 5 h and persisted at 6 d. The pattern of adhesion molecule expression that we have observed is similar to that seen in normal skin during a delayed hypersensitivity reaction. These observations support an immunologic basis for PMLE.

We have examined the expression of three endothelial adhesion molecules (intercellular adhesion molecule-1 [ICAM-1], endothelial leukocyte adhesion molecule-1 [ELAM-1], and vascular cell adhesion molecule-1 [VCAM-1]) in normal human skin following intradermal injection of stratum corneum-derived interleukin-1 alpha (SCIL-1 alpha). In control skin, constitutive expression of ICAM-1 was found on endothelial cells and at low levels on dermal dendritic cells but not on keratinocytes. ELAM-1 and VCAM-1 were present in low levels on endothelium and perivascular dendritic cells, respectively. SCIL-1 alpha injection produced marked endothelial ELAM-1 upregulation. Double staining with neutrophil elastase demonstrated that many ELAM-1-positive vessels contained marginating neutrophils and that interstitial neutrophils were clustered around ELAM-1-positive vessels. An increase in dermal dendritic cell ICAM-1 expression occurred and in two of three biopsies there was keratinocyte expression of ICAM-1 in the SCIL-1 alpha-injected tissue. Also, there was upregulation of VCAM-1 on vascular endothelium and an increase in the dermal dendritic cell expression of this molecule. These results give in vivo confirmation that SCIL-1 alpha modulated endothelial and dermal dendritic cell adhesion molecule expression, and show that endothelial VCAM-1 is regulated in vivo by SCIL-1 alpha, thus providing a regulatable ICAM-1-independent means of mononuclear cell recruitment.

A systematic study of keratin expression in epidermal lesions (six actinic keratoses, 10 Bowen's disease, seven squamous cell carcinomas) has been undertaken by using a large panel of monospecific monoclonal antibodies to individual keratins. Expression of differentiation-specific keratins was frequently delayed or lost from dysplastic regions. Novel expression of the embryonic, or simple epithelial, keratins 8 and 18 was widely observed in intradermal areas of poorly differentiated squamous cell carcinomas. In addition, the most proliferative of in situ malignancies (Bowen's disease) also contained small numbers of cells expressing simple epithelial keratins. These observations suggest that the expression of simple epithelial keratins may be of functional importance in malignancy of keratinocytes and could be related to tumor invasion and/or to changes in epithelial-mesenchymal interactions.

The purpose of this study was to determine the effect of interferon-gamma on keratinocyte major histocompatibility complex class II gene transcription. Transformed human foreskin keratinocytes (SVK14 cells) were incubated with recombinant IFN-gamma in the presence or absence of the protein synthesis inhibitor cycloheximide. Total cellular RNA was extracted from the cells and Northern blot analysis carried out using cDNA probes for all the functional class II genes. We report that 1) there is co-ordinate activation of all the class-II genes; 2) the rate of transcription varies between gene loci after activation; and 3) de novo protein synthesis is required for IFN-gamma activation of class II transcription.

An immunoelectron microscopic method was developed using T6 antiserum in an immunoperoxidase technique to label the dendritic cells of the epidermis in mycosis fungoides (MF). The technique allows simultaneous identification of intracellular Birbeck granules and T6 membrane positivity. Ultrastructural examination of the epidermal infiltrate of MF, using this method, confirmed the T6-positive nature of Langerhans cells and indeterminate cells. All Sézariform and mature lymphocytes were T6-negative and a small population of T6-negative histiocytic cells were also observed.

An immunoelectronomicroscopic method has been employed to demonstrate in situ the T lymphocyte nature of the dermal and epidermal infiltrates to mycosis fungoides. A specific antiserum to the human T lymphocyte surface antigen (HTLA) was used in an indirect reaction with a peroxidase labeled anti-immunoglobulin. After histochemically revealing the peroxidase activity, T cells were easily identified by the deposition of electron dense material on the cytoplasmic membrane. Counterstaining with uranyl acetate and lead citrate enabled us morphologically to observe the maturity of infiltrating T lymphocytes and to identify Sézary cells and other cells such as eosinophils in the infiltrate. Our results confirm the T cell nature of the dermal infiltrate in mycosis fungoides and show that the epidermal infiltrate of cells forming Pautrier micro-abscesses are predominantly T lymphocytes.

Beta 2-microglobulin (beta 2M) is part of the HLA molecule, and is found on the cell surface of human nucleated cells. In certain skin tumors, malignant change has been associated with a loss of this surface beta 2M, indicating a possible diagnostic value for this marker. At present beta 2M is best identified in paraffin-embedded tissue by means of a triple-layer peroxidase-antiperoxidase technique, using mammalian polyclonal antisera. Recently a polyclonal antiserum against human beta 2M has been produced in chickens. Because of the phylogenetic differences between the species, the resulting antiserum is likely to recognize more epitopes on the beta 2M and show greater sensitivity than antisera raised in mammalian species. To confirm this hypothesis, the avian antiserum was compared to both mammalian polyclonal (rabbit) and monoclonal (mouse) antibody in vitro. beta 2M fixed to plastic surfaces combined with more avian than mammalian antibody. Furthermore, insolubilized chicken antibody could bind more secondary antibody-horseradish peroxidase conjugate than could insolubilized mammalian antibody, thus showing even greater enhancement with this system. Immunohistochemical analysis of these systems confirmed that the chicken strategy has greater sensitivity, and can be used in an indirect system with consequent reduction in nonspecific background activity. It is the most suitable technique for the investigation of the distribution of beta 2M in paraffin-embedded tissue.

The influence of the sequential stages of conventional formaldehyde fixation and paraffin embedding of cutaneous tissue on monoclonal antibody labeling of cell surface antigens is described. The effects of variation in fixation time, dehydration, clearing, wax embedding, and enzyme treatment of cutaneous sections were examined. By curtailing fixation time, using cold ethanol dehydration, and limited cold clearing with xylene, immunoreactivity of several important monoclonal antibodies was retained. Wax embedding could be achieved at 58 degrees C for 1 h or by using low-melting-point wax at 42 degrees C for 3 h. Thus was derived an optimal processing procedure which afforded good tissue morphology and allowed reliable reproducible labeling by monoclonal antibodies to cell surface antigens.

Lymphocyte function associated antigen 1 (LFA-1) and its ligand intercellular adhesion molecule 1 (ICAM-1) are cell surface adhesion molecules important in many lymphocyte-mediated responses. Recent in vitro studies have demonstrated that the cytokine interferon-gamma (IFN-gamma) can induce ICAM-1 expression by keratinocytes, and that lymphocytes adhere to IFN-gamma treated keratinocytes. In view of the importance of keratinocyte/lymphocyte interactions in the pathogenesis of cutaneous disease, we have examined the effects of in vivo IFN-gamma on cutaneous expression of LFA-1 and ICAM-1. Fourteen volunteers received intradermal IFN-gamma (dose: 1 or 10 micrograms) daily for 3 d. Biopsy was obtained on day 6. Cryostat sections were stained by the peroxidase antiperoxidase technique employing murine monoclonal antibodies to CD11, CD18, and ICAM-1. IFN-gamma intensified ICAM-1 expression by dermal endothelial cells and induced keratinocyte expression of ICAM-1. Furthermore, after administration of 10 micrograms of IFN-gamma LFA-1 positive (LFA + ve) lymphocytes were observed along the basement membrane zone closely related to ICAM-1 + ve basal keratinocytes and also surrounding dermal endothelium. Exposure to IFN-gamma induced expression of both CD11a and CD18 antigens on epidermal Langerhans cells. These studies suggest that the distribution of adherence molecules expression within cutaneous tissue in vivo is modulated by IFN-gamma, and that these alterations may be important in interactions involving cutaneous immunocompetent cells.

Both type I and type IV hypersensitivity reactions have been implicated in the pathogenesis of atopic dermatitis. Using monoclonal antibodies we have identified IgE on the surface of cutaneous dendritic cells in both lesional and nonlesional skin. Double immunofluorescence labeling demonstrates these cells to be antigen-presenting cells. Immunoglobulin E (IgE) was not identified on such cells either in atopic individuals with no history of dermatitis or in patients with a range of other dermatoses. Further studies are consistent with IgE being bound to the cell surface via an Fc-IgE receptor. We conclude that this finding is specific for atopic dermatitis and thus may provide a link between the two types of hypersensitivity reactions frequently observed.

It has been proposed that immune dysfunction in psoriasis is a consequence of aberrant cyclic nucleotide metabolism. We have examined cyclic AMP responses to isoprenaline, histamine, and prostaglandin E2 in peripheral blood mononuclear leukocytes from patients with psoriasis, in the presence and absence of a potent cyclic AMP phosphodiesterase inhibitor. Stimulated and basal cyclic AMP levels in mononuclear leukocytes from psoriatics did not differ from those observed in mononuclear leukocytes from normal subjects, irrespective of the stimulant employed, either in the presence or in the absence of the phosphodiesterase inhibitor. These findings do not support the hypothesis that psoriasis is associated with either impaired beta-adrenergic reactivity or a more generalized abnormality of mononuclear leukocyte cyclic nucleotide metabolism.

Polyethylene glycol (PEG) was used as a probe molecule to investigate intestinal absorption in eight patients with eczema and evidence of food allergy and ten with eczema alone. In both groups absorption of molecules of larger molecular weight was greater than in normal subjects but absorption of molecules of low molecular weight was normal. There was no difference in absorption between eczema patients with or without food allergy. These results suggest that there is an intestinal mucosal defect in eczema which exists whether or not there is coexistent food allergy. Half the patients with eczema alone and two of the eight with food allergy had more of the large molecular weight PEG recovered in their urine in the second 12 h after ingestion than in the first 12 h. This could be the result of abnormal permeability in the more distal small bowel or even in the colon.

The ultrastructure of the human mucocutaneous end organ is described. The corpuscle is divided into sublobular units comprising axon terminals surrounded by generally concentric lamellar processes which are derived from laminar cells whose nuclei are situated towards the periphery of the sublobules. Interlamellar substance which contains elastic tissue, collagen and coarse periodicity crossbanded structures intervenes between lamellar processes. Specialized zones of contact resembling desmosomes are found at intervals seemingly connecting adjacent lamellar processes and axons with lamellar processes. The ultrastructural features of this end organ are similar to that of the Meissner corpuscle despite minor differences of the light microscopical appearance, which supports the view that differences in sensory end organs are merely variations on a common organizational basis.