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2.
Rev Sci Instrum ; 90(3): 035102, 2019 Mar.
Article in English | MEDLINE | ID: mdl-30927801

ABSTRACT

We demonstrate the use of a 3D printed radial collimator in X-ray powder diffraction and surface sensitive grazing incidence X-ray diffraction. We find a significant improvement in the overall signal to background ratio of up to 100 and a suppression of more than a factor 3 · 105 for undesirable Bragg reflections generated by the X-ray "transparent" windows of the sample environment. The background reduction and the removal of the high intensity signals from the windows, which limit the detector's dynamic range, enable significantly higher sensitivity in experiments within sample environments such as vacuum chambers and gas- or liquid-cells. Details of the additively manufactured steel collimator geometry, alignment strategies using X-ray fluorescence, and data analysis are also briefly discussed. The flexibility and affordability of 3D prints enable designs optimized for specific detectors and sample environments, without compromising the degrees of freedom of the diffractometer.

3.
Arch Gynecol Obstet ; 292(6): 1361-6, 2015 Dec.
Article in English | MEDLINE | ID: mdl-26112357

ABSTRACT

OBJECTIVE: "Every colposcopic criterion must be mirrored by histopathology". We investigated the histomorphologic equivalent of four colposcopic criteria, which are associated with CIN 2 and/or CIN 3 and therefore called pathognomonic. PATIENTS AND METHODS: We diagnosed inner border sign, ridge sign, rag sign and/or cuffed gland openings using VITOM(®) videocolposcopy in 255 patients which are consistent with major change. Histopathologic examination included immunohistochemical staining for p16, Ki 67 and stathmin-1 and micro-photographic documentation. RESULTS: The histopathologic pattern specific for each of the four pathognomonic colposcopic criteria was reproducibly identified: inner border sign showed a sharp demarcation between low- and high-grade CIN, in ridge sign high-grade CIN adjoined directly the squamocolumnar junction, in rag sign, high-grade CIN was detached from stroma, and in cuffed gland openings, the entrance to a gland was rimmed by CIN, respectively. In 255 patients, the leading pathognomonic sign was inner border in 12.1 %, ridge in 34.1 %, rag in 18 %, and cuffed glands in 35.7 %, respectively. Inner border sign, ridge sign, rag sign and/or cuffed gland openings were associated with CIN 2 or 3 in 97, 98, 98 and 98 %, respectively. In 153 out of 255 patients, we found a combination of pathognomonic signs with ridge sign being the most frequent combined criterion (in 21 % of patients as second pathognomonic sign). CONCLUSION: The morphology of the four pathognomonic colposcopic criteria, inner border sign, ridge sign, rag sign and cuffed crypt openings, is reproduced in histopathology. These criteria are highly associated with CIN 2 or CIN 3.


Subject(s)
Colposcopy/methods , Uterine Cervical Dysplasia/diagnosis , Uterine Cervical Neoplasms/diagnosis , Adult , Aged , Carcinoma, Squamous Cell/pathology , Female , Humans , Middle Aged , Photography , Physical Examination , Predictive Value of Tests , Pregnancy , Reproducibility of Results
4.
J Exp Bot ; 66(8): 2187-97, 2015 Apr.
Article in English | MEDLINE | ID: mdl-25821072

ABSTRACT

Biotic stress and diseases caused by pathogen attack pose threats in crop production and significantly reduce crop yields. Enhancing immunity against pathogens is therefore of outstanding importance in crop breeding. However, this must be balanced, as immune activation inhibits plant growth. This immunity-coupled growth trade-off does not support resistance but is postulated to reflect the reallocation of resources to drive immunity. There is, however, increasing evidence that growth-immunity trade-offs are based on the reconfiguration of hormone pathways, shared by growth and immunity signalling. Studies in roots revealed the role of hormones in orchestrating growth across different cell types, with some hormones showing a defined cell type-specific activity. This is apparently highly relevant for the regulation of the cell cycle machinery and might be part of the growth-immunity cross-talk. Since plants are constantly exposed to Immuno-activating microbes under agricultural conditions, the transition from a growth to an immunity operating mode can significantly reduce crop yield and can conflict our efforts to generate next-generation crops with improved yield under climate change conditions. By focusing on roots, we outline the current knowledge of hormone signalling on the cell cycle machinery to explain growth trade-offs induced by immunity. By referring to abiotic stress studies, we further introduce how root cell type-specific hormone activities might contribute to growth under immunity and discuss the feasibility of uncoupling the growth-immunity cross-talk.


Subject(s)
Cell Cycle/drug effects , Plant Development/drug effects , Plant Growth Regulators/pharmacology , Plant Immunity/drug effects , Signal Transduction/drug effects , Stress, Physiological/drug effects
5.
J Exp Bot ; 66(8): 2177-86, 2015 Apr.
Article in English | MEDLINE | ID: mdl-25743160

ABSTRACT

Plant root rhizosphere interactions with mutualistic microbes are diverse and numerous, having evolved over time in response to selective pressures on plants to attain anchorage and nutrients. These relationships can be considered to be formed through a combination of architectural connections: molecular architecture interactions that control root-microbe perception and regulate the balance between host and symbiont and developmental architecture interactions that enable the microbes to be 'housed' in the root and enable the exchange of compounds. Recent findings that help to understand the common architecture that exists between nodulation and mycorrhizal interactions, and how this architecture could be re-tuned to develop new symbioses, are discussed here.


Subject(s)
Biological Evolution , Introduced Species , Microbial Interactions , Plant Roots/microbiology , Symbiosis , Plant Root Nodulation/genetics , Plant Roots/genetics , Symbiosis/genetics
6.
Geburtshilfe Frauenheilkd ; 75(10): 1063-1068, 2015 Oct.
Article in English | MEDLINE | ID: mdl-28435170

ABSTRACT

Introduction: To evaluate, if targeted strip biopsies decrease trauma/pain perception while maintaining diagnostic accuracy in patients with the diagnosis of high-grade squamous intraepithelial lesions of the uterine cervix. Patients and Methods: Between July 1st and December 31st 2014 we performed colposcopically directed strip biopsies in 102 patients with colposcopic suspicion of high-grade squamous intraepithelial lesions of the uterine cervix. We used a 3 mm curette for harvesting tissue samples under VITOM® videocolposcopy. So far, 60 patients underwent additional loop excision. Histologic examination of strip biopsies and loop specimens included routine hematoxylin and eosin staining as well as immunohistochemical staining for p16, Ki 67 and stathmin-1. Results: 55 patients (53 %), were histologically diagnosed with cervical intraepithelial neoplasia grade 3 on strip biopsies. Adenocarcinoma in situ was diagnosed in 2 patients (2 %), cervical intraepithelial neoplasia grade 2 in 35 patients (34 %), and cervical intraepithelial neoplasia grade 1 in 10 patients (10 %). The agreement between histologic results of strip biopsy and loop specimen was highly significant: In all 60 strip biopsies diagnosed with high-grade squamous intraepithelial lesions this diagnosis was confirmed histologically during follow-up loop specimen excision (high-grade squamous intraepithelial lesions in 58 patients, invasive disease in 2 patients). The pain level experienced during strip biopsy was rated on average 0.25 on a scale from 0 to 10. No clinically significant bleeding was reported. Conclusion: Targeted strip biopsies with a 3 mm curette are a reliable procedure to diagnose high-grade squamous intraepithelial lesions of the uterine cervix and yield high patient satisfaction (Video 1).

7.
Nat Commun ; 5: 5388, 2014 Nov 05.
Article in English | MEDLINE | ID: mdl-25369851

ABSTRACT

Molecular semiconductors are increasingly used in devices, but understanding of elementary nanoscopic processes in molecular film growth is in its infancy. Here we use real-time in situ specular and diffuse X-ray scattering in combination with kinetic Monte Carlo simulations to study C60 nucleation and multilayer growth. We determine a self-consistent set of energy parameters describing both intra- and interlayer diffusion processes in C60 growth. This approach yields an effective Ehrlich-Schwoebel barrier of EES=110 meV, diffusion barrier of ED=540 meV and binding energy of EB=130 meV. Analysing the particle-resolved dynamics, we find that the lateral diffusion is similar to colloids, but characterized by an atom-like Schwoebel barrier. Our results contribute to a fundamental understanding of molecular growth processes in a system, which forms an important intermediate case between atoms and colloids.

8.
Cell Signal ; 26(9): 2016-29, 2014 Sep.
Article in English | MEDLINE | ID: mdl-24882690

ABSTRACT

Apremilast, an oral small molecule inhibitor of phosphodiesterase 4 (PDE4), is in development for chronic inflammatory disorders, and has shown efficacy in psoriasis, psoriatic arthropathies, and Behçet's syndrome. In March 2014, the US Food and Drug Administration approved apremilast for the treatment of adult patients with active psoriatic arthritis. The properties of apremilast were evaluated to determine its specificity, effects on intracellular signaling, gene and protein expression, and in vivo pharmacology using models of innate and adaptive immunity. Apremilast inhibited PDE4 isoforms from all four sub-families (A1A, B1, B2, C1, and D2), with IC50 values in the range of 10 to 100 nM. Apremilast did not significantly inhibit other PDEs, kinases, enzymes, or receptors. While both apremilast and thalidomide share a phthalimide ring structure, apremilast lacks the glutarimide ring and thus fails to bind to cereblon, the target of thalidomide action. In monocytes and T cells, apremilast elevated intracellular cAMP and induced phosphorylation of the protein kinase A substrates CREB and activating transcription factor-1 while inhibiting NF-κB transcriptional activity, resulting in both up- and down-regulation of several genes induced via TLR4. Apremilast reduced interferon-α production by plasmacytoid dendritic cells and inhibited T-cell cytokine production, but had little effect on B-cell immunoglobulin secretion. In a transgenic T-cell and B-cell transfer murine model, apremilast (5mg/kg/day p.o.) did not affect clonal expansion of either T or B cells and had little or no effect on their expression of activation markers. The effect of apremilast on innate immunity was tested in the ferret lung neutrophilia model, which allows monitoring of the known PDE4 inhibitor gastrointestinal side effects (nausea and vomiting). Apremilast significantly inhibited lung neutrophilia at 1mg/kg, but did not induce significant emetic reflexes at doses <30 mg/kg. Overall, the pharmacological effects of apremilast are consistent with those of a targeted PDE4 inhibitor, with selective effects on innate immune responses and a wide therapeutic index compared to its gastrointestinal side effects.


Subject(s)
Immunity, Innate/drug effects , Phosphodiesterase 4 Inhibitors/pharmacology , Thalidomide/analogs & derivatives , Adaptive Immunity/drug effects , Animals , B-Lymphocytes/drug effects , B-Lymphocytes/immunology , B-Lymphocytes/metabolism , Cell Line , Cyclic AMP/metabolism , Cyclic Nucleotide Phosphodiesterases, Type 4/chemistry , Cyclic Nucleotide Phosphodiesterases, Type 4/metabolism , Cytokines/metabolism , Disease Models, Animal , Female , Ferrets , Humans , Jurkat Cells , Lung Diseases/drug therapy , Male , Mice , Mice, Transgenic , Phosphodiesterase 4 Inhibitors/metabolism , Phosphodiesterase 4 Inhibitors/therapeutic use , Protein Binding , T-Lymphocytes/drug effects , T-Lymphocytes/immunology , T-Lymphocytes/metabolism , Thalidomide/metabolism , Thalidomide/pharmacology , Thalidomide/therapeutic use , Vomiting/prevention & control
9.
Z Gastroenterol ; 52(1): 22-6, 2014 Jan.
Article in German | MEDLINE | ID: mdl-24420795

ABSTRACT

Rudolf Schindler (1888 - 1968) accelerated the spread of gastroscopy in various ways. Together with the technical expert Georg Wolf he developed in 1932 the semiflexible gastroscope, which for about 25 years was the standard gastroscope worldwide before the onset of the fiberscopic era. With his previously constructed rigid gastroscope he became the founder of routine gastroscopy. His Lehrbuch und Atlas der Gastroskopie made him the leading endoscopic authority. He founded the ambulant gastroenterological-endoscopic practice. He was the first to describe and differentiate gastritis. In 1941 he founded the American Gastroscopic Club, he was its first president and the first editor of the journal of this society. For about 40 years he practiced gastroscopy every day with his wife Gabriele. Last but not least, Schindler was a leading authority, which attracted a steadily increasing number of pupils. Schindler was born and grew up in Berlin. He made most of his innovations in Munich between 1920 and 1934. An arrest by the Nazis of two months duration in 1934 drove him away from Germany. In the next decade he made Chicago the Mekka of gastroscopy. In 1943 he moved to California, From 1958 through to 1950 he worked in Belo Horizonte, Brasil. He spent his last years again in Munich. Schindler, possibly the best known digestive endoscopist and an innovative artistical personality, received worldwide high acceptance.


Subject(s)
Gastroenterology/history , Gastroscopy/history , Germany , History, 20th Century
11.
Eur Arch Otorhinolaryngol ; 271(1): 133-40, 2014 Jan.
Article in English | MEDLINE | ID: mdl-23812585

ABSTRACT

The aim of the study was to compare device life of more recent indwelling voice prostheses Provox Vega and Blom-Singer Dual Valve to device life of well-known standard devices (Provox 2, Blom-Singer Classic). In a prospective, non-randomised study, device life of Blom-Singer Classic, Blom-Singer Dual Valve, Provox2, Provox Vega and Provox ActiValve voice prostheses was recorded in a group of 102 laryngectomised patients. In total 749 voice prosthesis were included. Average overall life time was 108 days, median 74 days. The prosthesis with the longest dwell time was the Provox ActiValve (median 291 days). Provox Vega had longer device life compared with Provox2 (median 92 days vs 66 days; p = 0.006) and compared with Blom-Singer Classic (median 92 days vs 69 days; p = 0.004). In conclusion, device lifetimes of Provox Vega and ActiValve were better than those of Provox2 and the Blom-Singer Classic. New voice prostheses, with a defined valve opening pressure (Provox Vega, Provox ActiValve, Blom-Singer Dual Valve) had longer lifetimes than prostheses without a defined opening pressure (Blom-Singer Classic and Provox 2).


Subject(s)
Larynx, Artificial , Prosthesis Design , Adult , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Prospective Studies
12.
Infection ; 41(4): 799-809, 2013 Aug.
Article in English | MEDLINE | ID: mdl-23435720

ABSTRACT

OBJECTIVES: Current guidelines provide limited evidence as to which patients with urinary tract infection (UTI) require hospitalisation. We evaluated the currently used triage routine and tested whether a set of criteria including biomarkers like proadrenomedullin (proADM) and urea have the potential to improve triage decisions. METHODS: Consecutive adults with UTI presenting to our emergency department (ED) were recruited and followed for 30 days. We defined three virtual triage algorithms, which included either guideline-based clinical criteria, optimised admission proADM or urea levels in addition to a set of clinical criteria. We compared actual treatment sites and observed adverse events based on the physician judgment with the proportion of patients assigned to treatment sites according to the three virtual algorithms. Adverse outcome was defined as transfer to the intensive care unit (ICU), death, recurrence of UTI or rehospitalisation for any reason. RESULTS: We recruited 127 patients (age 61.8 ± 20.8 years; 73.2 % females) and analysed the data of 123 patients with a final diagnosis of UTI. Of these 123 patients, 27 (22.0 %) were treated as outpatients. Virtual triage based only on clinical signs would have treated only 22 (17.9 %) patients as outpatients, with higher proportions of outpatients equally in both biomarker groups (29.3 %; p = 0.02). There were no significant differences in adverse events between outpatients according to the clinical (4.5 %), proADM (2.8 %) or urea groups (2.8 %). The mean length of stay was 6.6 days, including 2.2 days after reaching medical stability. CONCLUSIONS: Adding biomarkers to clinical criteria has the potential to improve risk-based triage without impairing safety. Current rates of admission and length of stay could be shortened in patients with UTI.


Subject(s)
Biomarkers/analysis , Clinical Laboratory Techniques/methods , Clinical Medicine/methods , Hospitalization , Urinary Tract Infections/diagnosis , Urinary Tract Infections/drug therapy , Adult , Aged , Aged, 80 and over , Female , Humans , Length of Stay/statistics & numerical data , Male , Middle Aged , Prospective Studies , Urinary Tract Infections/pathology
13.
Hernia ; 17(6): 809-12, 2013 Dec.
Article in English | MEDLINE | ID: mdl-23011737

ABSTRACT

In this paper, we present a rare case of a small bowel obstruction secondary to an incarcerated inguinal hernia as a short-term complication of a penile prosthesis implantation. The patient underwent prosthesis implantation to treat refractory erectile dysfunction after a robotic-assisted laparoscopic radical prostatectomy. He presented 2 weeks later with the incarcerated hernia to our emergency department and surgical service. The hernia was repaired in a tension-free manner, and the bowel was uncompromised. The patient is symptom free at follow-up.


Subject(s)
Hernia, Inguinal/etiology , Intestinal Obstruction/etiology , Intestine, Small , Penile Prosthesis , Postoperative Complications , Prosthesis Implantation , Hernia, Inguinal/diagnosis , Humans , Intestinal Obstruction/diagnosis , Male , Middle Aged , Postoperative Complications/diagnosis
14.
J Chem Phys ; 136(20): 204709, 2012 May 28.
Article in English | MEDLINE | ID: mdl-22667583

ABSTRACT

We compare the growth dynamics of the three n-alkanes C(36)H(74), C(40)H(82), and C(44)H(90) on SiO(2) using real-time and in situ energy-dispersive x-ray reflectivity. All molecules investigated align in an upright-standing orientation on the substrate and exhibit a transition from layer-by-layer growth to island growth after about 4 monolayers under the conditions employed. Simultaneous fits of the reflected intensity at five distinct points in reciprocal space show that films formed by longer n-alkanes roughen faster during growth. This behavior can be explained by a chain-length dependent height of the Ehrlich-Schwoebel barrier. Further x-ray diffraction measurements after growth indicate that films consisting of longer n-alkanes also incorporate more lying-down molecules in the top region. While the results reveal behavior typical for chain-like molecules, the findings can also be useful for the optimization of organic field effect transistors where smooth interlayers of n-alkanes without coexistence of two or more molecular orientations are required.

15.
Leukemia ; 26(11): 2326-35, 2012 Nov.
Article in English | MEDLINE | ID: mdl-22552008

ABSTRACT

Thalidomide and the immunomodulatory drug, lenalidomide, are therapeutically active in hematological malignancies. The ubiquitously expressed E3 ligase protein cereblon (CRBN) has been identified as the primary teratogenic target of thalidomide. Our studies demonstrate that thalidomide, lenalidomide and another immunomodulatory drug, pomalidomide, bound endogenous CRBN and recombinant CRBN-DNA damage binding protein-1 (DDB1) complexes. CRBN mediated antiproliferative activities of lenalidomide and pomalidomide in myeloma cells, as well as lenalidomide- and pomalidomide-induced cytokine production in T cells. Lenalidomide and pomalidomide inhibited autoubiquitination of CRBN in HEK293T cells expressing thalidomide-binding competent wild-type CRBN, but not thalidomide-binding defective CRBN(YW/AA). Overexpression of CRBN wild-type protein, but not CRBN(YW/AA) mutant protein, in KMS12 myeloma cells, amplified pomalidomide-mediated reductions in c-myc and IRF4 expression and increases in p21(WAF-1) expression. Long-term selection for lenalidomide resistance in H929 myeloma cell lines was accompanied by a reduction in CRBN, while in DF15R myeloma cells resistant to both pomalidomide and lenalidomide, CRBN protein was undetectable. Our biophysical, biochemical and gene silencing studies show that CRBN is a proximate, therapeutically important molecular target of lenalidomide and pomalidomide.


Subject(s)
Adjuvants, Immunologic/pharmacology , Antineoplastic Agents/pharmacology , Peptide Hydrolases/drug effects , Thalidomide/analogs & derivatives , Adaptor Proteins, Signal Transducing , HEK293 Cells , Humans , Lenalidomide , Thalidomide/pharmacology , Ubiquitin-Protein Ligases , Ubiquitination
16.
Orthopade ; 41(1): 15-9, 2012 Jan.
Article in German | MEDLINE | ID: mdl-22273702

ABSTRACT

Preoperative diagnosis of periprosthetic infections is particularly important before revision of knee and hip arthroplasties because of the therapeutic consequences. Therefore, periprosthetic infections should be ruled out before any revision surgery is performed. Of the different diagnostic methods direct techniques which allow the direct detection of microorganisms with testing of antibiotic sensitivity are recommended. This allows microorganism-specific systemic and local antibiotic therapies and helps to reduce the risk of development of resistance. In our studies it could be shown that the time for incubation to detect microorganisms should be 14 days and that biopsy of periprosthetic tissues is superior to aspiration alone because it combines several diagnostic methods (microbiological and histological). It is preferable to repeating an aspiration when data are unclear, i.e. in cases of potentially false positives or negatives results of aspiration.


Subject(s)
Anti-Bacterial Agents/therapeutic use , Bacterial Infections/pathology , Bacterial Infections/prevention & control , Biopsy, Needle/methods , Prosthesis-Related Infections/pathology , Prosthesis-Related Infections/prevention & control , Humans , Reoperation
17.
Geburtshilfe Frauenheilkd ; 72(5): 412-418, 2012 May.
Article in English | MEDLINE | ID: mdl-25298546

ABSTRACT

Hamartomas can occur in different areas of the breast, but they are rarely found in the breast. Myoid hamartomas with smooth muscle cells of the type described here are particularly unusual. The pathogenesis of this benign entity with its tendency to growth and recurrence is not clear. Excision is the therapy of choice. Capillary hemangiomas are rare vascular malformations of the breast which, in contrast to cavernous hemangiomas, usually remain clinically occult. It is important to differentiate these benign findings from malignant angiosarcoma. The possible heterogeneities between myoid hamartoma and capillary hemangioma using current breast imaging methods for the differential diagnosis (high-resolution ultrasound, duplex sonography, shear wave elastography, digital mammography, minimally invasive intervention) are discussed together with an overview of the literature.

18.
Neuroscience ; 168(3): 820-30, 2010 Jul 14.
Article in English | MEDLINE | ID: mdl-20144696

ABSTRACT

Endothelin-1 exerts potent vasoconstrictor and vasodilatory effects through its actions on its receptors A (ETrA) and B (ETrB), respectively. While ETrA and B have classically been thought to be expressed on vascular cell types, more recent evidence suggests that, particularly following brain injury, their expression may be seen in other, non-vascular cell types. To date no studies have comprehensively studied the cellular location of endothelin receptors following traumatic brain injury (TBI). Therefore, this study investigates the cellular localization of ETrA and B in normal and traumatized brains using an impact acceleration device. Adult male Sprague-Dawley rats were subjected to TBI by weight drop (450 g) from either 1.5, a distance known to elicit mild TBI in the absence of changed in cerebral blood flow (CBF) or 2 m, a distance shown to cause a significant reduction in CBF. One set of impacted brains were processed for Western determination of ETrA and B expression. Another set were processed for immunofluorescence (IF). For IF, ETrA and ETrB antibodies were combined with cell markers for neurons, astrocytes, microglia, oligodendrocytes, smooth muscle cells and endothelial cells of blood vessels. While ETrA and B was upregulated after more moderate to severe injury (2 m) overall receptor expression was unchanged in response to mild trauma (1.5 m). Double labeling IF confirmed prominent ETrA and ETrB labeling in NeuN labeled pyramidal neurons and interneurons in sensorymotor cortex (smCx) and hippocampus (hipp) post TBI. ETrA rather than ETrB was preferentially co-localized in vascular smooth muscle cells. After injury, a subpopulation of astrocytes in white matter co-localized ETrA but not ETrB. Localization of either receptor in endothelial cells was sparse. No prominent IF was detected in microglia and oligodendrocytes. Taken together with previous findings in other pathological states that show an apparent shift in the localization of ETrA and B, the observed receptor shifts in this work may underlie the ET-1-mediated pathotrajectory of TBI including hypoperfusion.


Subject(s)
Brain Injuries/metabolism , Brain/metabolism , Receptor, Endothelin A/biosynthesis , Receptor, Endothelin B/biosynthesis , Animals , Astrocytes/metabolism , Brain/blood supply , Disease Models, Animal , Endothelial Cells/metabolism , Interneurons/metabolism , Male , Myocytes, Smooth Muscle/metabolism , Oligodendroglia/metabolism , Pyramidal Cells/metabolism , Rats , Rats, Sprague-Dawley
19.
Br J Pharmacol ; 159(4): 842-55, 2010 Feb.
Article in English | MEDLINE | ID: mdl-20050849

ABSTRACT

BACKGROUND AND PURPOSE: Apremilast is an orally administered phosphodiesterase-4 inhibitor, currently in phase 2 clinical studies of psoriasis and other chronic inflammatory diseases. The inhibitory effects of apremilast on pro-inflammatory responses of human primary peripheral blood mononuclear cells (PBMC), polymorphonuclear cells, natural killer (NK) cells and epidermal keratinocytes were explored in vitro, and in a preclinical model of psoriasis. EXPERIMENTAL APPROACH: Apremilast was tested in vitro against endotoxin- and superantigen-stimulated PBMC, bacterial peptide and zymosan-stimulated polymorphonuclear cells, immunonoglobulin and cytokine-stimulated NK cells, and ultraviolet B light-activated keratinocytes. Apremilast was orally administered to beige-severe combined immunodeficient mice, xenotransplanted with normal human skin and triggered with human psoriatic NK cells. Epidermal skin thickness, proliferation index and inflammation markers were analysed. KEY RESULTS: Apremilast inhibited PBMC production of the chemokines CXCL9 and CXCL10, cytokines interferon-gamma and tumour necrosis factor (TNF)-alpha, and interleukins (IL)-2, IL-12 and IL-23. Production of TNF-alpha by NK cells and keratinocytes was also inhibited. In vivo, apremilast significantly reduced epidermal thickness and proliferation, decreased the general histopathological appearance of psoriasiform features and reduced expression of TNF-alpha, human leukocyte antigen-DR and intercellular adhesion molecule-1 in the lesioned skin. CONCLUSIONS AND IMPLICATIONS: Apremilast displayed a broad pattern of anti-inflammatory activity in a variety of cell types and decreased the incidence and severity of a psoriasiform response in vivo. Inhibition of TNF-alpha, IL-12 and IL-23 production, as well as NK and keratinocyte responses by this phosphodiesterase-4 inhibitor suggests a novel approach to the treatment of psoriasis.


Subject(s)
Anti-Inflammatory Agents/pharmacology , Phosphodiesterase 4 Inhibitors , Phosphodiesterase Inhibitors/pharmacology , Psoriasis/drug therapy , Skin/drug effects , Thalidomide/analogs & derivatives , Administration, Oral , Adult , Animals , Anti-Inflammatory Agents/administration & dosage , Cell Proliferation/drug effects , Cyclic Nucleotide Phosphodiesterases, Type 4/metabolism , Cytokines/genetics , Cytokines/metabolism , Disease Models, Animal , Dose-Response Relationship, Drug , Enterotoxins/immunology , Gene Expression Regulation/drug effects , Humans , Inflammation Mediators/metabolism , Keratinocytes/drug effects , Keratinocytes/enzymology , Keratinocytes/immunology , Killer Cells, Natural/drug effects , Killer Cells, Natural/enzymology , Killer Cells, Natural/immunology , Leukocytes, Mononuclear/drug effects , Leukocytes, Mononuclear/enzymology , Leukocytes, Mononuclear/immunology , Lipopolysaccharides/pharmacology , Mice , Mice, SCID , Middle Aged , Phosphodiesterase Inhibitors/administration & dosage , Psoriasis/enzymology , Psoriasis/genetics , Psoriasis/immunology , Psoriasis/pathology , RNA, Messenger/metabolism , Severity of Illness Index , Skin/enzymology , Skin/immunology , Skin/pathology , Skin/radiation effects , Skin Transplantation , Thalidomide/administration & dosage , Thalidomide/pharmacology , Time Factors , Transplantation, Heterologous , U937 Cells , Ultraviolet Rays , Zymosan/metabolism
20.
Curr Cancer Drug Targets ; 10(2): 155-67, 2010 Mar.
Article in English | MEDLINE | ID: mdl-20088798

ABSTRACT

To determine the effect of dexamethasone on the antimyeloma effects of lenalidomide, we tested in vitro proliferation, tumor suppressor gene expression, caspase activity, cell cycling, and apoptosis levels in a series of multiple myeloma (MM) and plasma cell leukemia cell lines treated with lenalidomide and dexamethasone, alone or in combination. The effect of dexamethasone on the immunomodulatory activities of lenalidomide such as T cell and natural killer (NK) cell activation was measured via interleukin [IL]-2 production, and interferon-gamma and granzyme B production respectively. Lenalidomide inhibited proliferation in most cell lines tested, and this effect was enhanced by dexamethasone. This effect was observed in MM cells containing the high-risk cytogenetic abnormalities t(4;14), t(14;16), del17p, del13, and hypodiploidy. Mechanistically, lenalidomide plus dexamethasone synergistically induced expression of the tumor suppressor genes Egr1, Egr2, Egr3, p15, p21, and p27 in MM cell lines and MM patient cells. The combination activated caspases 3, 8, and 9; and induced cell cycle arrest and apoptosis. Lenalidomide alone increased T cell production of IL-2, and NK cell production of interferon-gamma and granzyme B. Notably, dexamethasone antagonized these immunostimulatory effects of lenalidomide in a dose-dependent manner. These data further elucidate the mechanism of action of lenalidomide and dexamethasone in MM, and suggest that use of low-dose dexamethasone with lenalidomide may retain the antiproliferative effect of lenalidomide while permitting greater immunomodulatory effects of this combination regimen.


Subject(s)
Dexamethasone/therapeutic use , Killer Cells, Natural/immunology , Multiple Myeloma/drug therapy , T-Lymphocytes/immunology , Thalidomide/analogs & derivatives , Adenosine Triphosphate/metabolism , Apoptosis/drug effects , Biomarkers, Tumor/genetics , Biomarkers, Tumor/metabolism , Blotting, Western , Caspase Inhibitors , Caspases/metabolism , Cell Proliferation/drug effects , Drug Synergism , Gene Expression Profiling , Humans , Immunomodulation/drug effects , Interferon-gamma/metabolism , Interleukin-2/metabolism , Lenalidomide , Multiple Myeloma/immunology , Multiple Myeloma/pathology , Oligonucleotide Array Sequence Analysis , Phosphorylation/drug effects , Retinoblastoma Protein/metabolism , Thalidomide/therapeutic use , Tumor Cells, Cultured , Tumor Suppressor Proteins/genetics , Tumor Suppressor Proteins/metabolism
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