Untersuchungen zur stereokontrollierten Synthese von 3-Mercaptolysinderivaten und Untersuchungen zur Synthese von Ansa-Seco-Steroiden

Untersuchungen zur stereokontrollierten Synthese von 3-Mercaptolysinderivaten: 3-Mercaptolysin und Peptide mit einer 3-Mercaptolysin-Einheit sind als Liganden für Nukleardiagnostika in der Kontrastmittelforschung von großem Interesse. Für das Screening Gewebe-selektiver Diagnostika sollten Mercaptolysinderivate, die sich für den Einbau in Peptide eignen, stereokontrolliert aufgebaut werden. Als Grundlage wurde im Rahmen dieser Arbeit eine sehr effiziente Synthese von Methoxymethyl-(4-oxo-butyl)-carbaminsäure-tert-butylester aus Pent-4-en-1-ol entwickelt. Nach Olefinierung des Aldehyds konnten Auxiliar-substituierte 6-Amino-hexensäure-derivate in guten Ausbeuten erhalten werden. Diese bildeten die Startmaterialien für auxiliargesteuerte Aziridinierungen mit anschließender Ringöffnung durch Schwefel-Nukleophile. Zudem wurden Azidierungen an Auxiliar-bewehrten Substraten, Michael-Additionen von Schwefel-Nukleophilen an Dehydroaminosäuren und viele weitere Reaktionen untersucht. Es galt dabei auf patentrechtlich geschützte Reaktionen zu verzichten, weil die Produkte ggf. in großem Maßstab kommerziell genutzt werden sollen. Dabei konnten alle vier stereoisomeren 2-Acetylamino-6-(tert-butoxycarbonyl-methoxymethyl-amino)-3-(4-methoxy-benzylsulfanyl)-hexansäurementhylester in guter Ausbeute synthetisiert werden. Nach Herstellung größerer Mengen der entsprechenden am Schwefelatom ungeschützten N-Fmoc-Aminosäurederivate sollen alle vier Stereoisomere in Peptide eingebaut und auf ihre Eignung als Liganden in Nukleardiagnostika untersucht werden. Untersuchungen zur Synthese neuartiger Ansa-Steroide: Über die Synthese von Ansa-Seco-Steroiden mittels eine Kaskade von intermolekularer Diels-Alder-Reaktion und anschließender Retro-Diels-Alder-Reaktion an 5,6,7,8-Tetradehydrosteroiden wurde erstmals 1986 von E. Winterfeldt et al. berichtet. Die damit eröffnete Möglichkeit eines völlig neuen Zugangs zu pharmakologisch interessanten Makrolid-Substraten konnte aber bislang nicht effektiv genutzt werden, weil insbesondere im Zusammenhang mit der Diels-Alder-Reaktion erhebliche präparative Probleme auftraten: Brauchbare Reaktivität nur bei sehr wenigen Dienophilen, Regioselektivitätsprobleme, etc. Hier galt es zu untersuchen, inwiefern sich diese Probleme durch die intramolekulare Reaktionsführung der Cycloaddition unterdrücken lassen können. Für die intramolekulare Diels-Alder-Reaktion zwischen der 5,7-Dien-Einheit des Steroids und einer an das Substrat gebundenen Dienophil-Einheit ist die Möglichkeit einer günstigen Anordnung der beiden Reaktanden-Gruppen entscheidend. Dafür wurden umfangreiche Untersuchungen zur alpha-konfigurierten Anbindung eines Dienophils in die 3-Position an 3-Hydroxy-5,6,7,8-Tetradehydrosteroiden durchgeführt: Mitsunobu-Reaktionen, Oxidations-Reduktions-Sequenzen, Oxidations-Ketalisierungs-Sequenzen, etc. Hierbei wurden zahlreiche neue Steroide synthetisiert. Es gelang jedoch nicht, 5,6,7,8-Tetradehydrosteroide mit axial in Position 3 eingebundenen Dienophilen in präparativ nutzbaren Mengen zu synthetisieren. Bei der Untersuchung intermolekularer Diels-Alder-Reaktionen zwischen Ergosterol und Brommaleinsäureanhydrid wurde vorzugsweise die Bildung der Addukte des 7,8,14,15-Tetradehydroisomers des Ergosterols beobachtet.

Aufbau und Kupplung von Schlüsselintermediaten zur enantioselektiven Steroidsynthese

Steroide sind im Organismus weit verbreitete, vielfältig substituierte Naturstoffe mit einem breiten biologischen Wirkungsspektrum. C/D-cis-verknüpfte Steroide kommen in der Natur zwar selten vor, sie sind aber in ihrer pharmakologischen Aktivität nicht weniger interessant. Total- bzw. Partialsynthesen sind bisher in der Literatur kaum beschrieben worden. Die Arbeit beschäftigt sich mit grundlegenden Reaktionen zur enantioselektiven Synthese eines 13,14-cis-verknüpften Steroids. Als Fernziel wurde C/D-cis-verknüpftes Östradiol ausgewählt mit der Option, das Substitutionsmuster dieses Steroids vielfältig variieren zu können. Der Syntheseplan beinhaltet zunächst den Aufbau des Kohlenstoffgerüsts im Sinne einer konvergenten Synthese, abschließende Cyclisierungen sollten dann das vollständige Molekül ergeben. Im Rahmen dieser Arbeit wurde zunächst das C/D-Ringfragment als Allylamin hergestellt. Das Amin ist dabei als chirales Auxiliar ausgelegt. Als A,B-Ringfragment wurden eine Reihe 4-Aryl-2,3-ungesättigte Carbonsäurefluoride synthetisiert. Im Verknüpfungsschritt, einer zwitterionischen Aza-Claisen-Umlagerung, konnten nun beide Fragmente mit hoher simpler, aber mäßiger induzierter Diastereoselektivität gekuppelt werden. Das Entfernen der Doppelbindung im Produkt erwies sich als erhebliche Hürde, die jedoch durch die Verwendung eines Enolethers genommen werden konnte. Das im Rahmen der Arbeit hergestellte Material sollte nun in wenigen Stufen zum C/D- cis-verknüpften Steroid umgesetzt werden können.

Valutazione dell'efficacia e della sicurezza dell'Infliximab e della Ciclosporina Orale Microemulsione (Neoral) nei pazienti con colite ulcerosa severa refrattari agli steroidi per via endovenosa. Risultati preliminari di uno studio randomizzato controllato

Background. Intravenous steroids represent the mainstay of therapy for severe attacks of Ulcerative Colitis (UC). In steroid refractory patients, both iv cyclosporine (CsA) and infliximab (IFX) are valid rescue therapies. Several studies have shown that oral microemulsion CsA (Neoral) is equivalent to iv CsA in term of safety and efficacy in UC patients. Aim. To investigate the efficacy and safety of oral microemulsion CsA vs IFX in patients with severe attack of UC, refractory to iv steroids. Material and methods. From May 2006, all consecutive pts admitted for severe UC were considered eligible. Pts were treated with iv steroid, according to the Oxford regime. After 1 week of intensive treatment, pts non responder to the therapy and not candidate to the surgery, were asked to participate to the trial. They were randomised to receive IFX 5 mg/kg or oral CsA 5 mg/kg. Results. A total of 30 patients were randomised, 17 in the IFX group and 13 in the CsA group. One month after study inclusion, 9 patients of the IFX group (53%) and 7 pts of the CsA group (54%) were in clinical remission (p=0.96), with a Powell-Tuck index ≤ 3. At the end of the follow-up, 7 pts in the IFX group (41%) vs 4 in the CsA group (31%) (p=0.35) underwent colectomy. The total cost of the IFX therapy with IFX was 8.052,84 € versus 1.106,82 €, for each patient. Conclusions. Oral microemulsion CsA and IFX seem to be equivalent in term of efficacy and safety in severe UC patients refractory to iv steroids. In patients treated with IFX the cost of therapy were significantly higher.

Alterazioni del metabolismo osseo e fratture vertebrali dopo trapianto di rene

Introduction:Persistent Hyperparathyroidism after transplantation (HPT),bone disease and vertebral fractures are an important clinical problem in renal transplant patients. Several factors such as renal osteodystrophy, immunosuppressive therapy, deficit/insufficiency Vitamin D may contribute to that.In literature are described different percentages of HPT, vertebral fractures and Osteoporosis/Osteopenia that may be due to the different therapy and to the different employ of steroid. We analyzed 90 patients who received a renal graft between 2005 e 2010. Patients and Methods: 44 male and 46 female. Average age 52,2± 10,1 years, follow-up 31,3±16,6 months, time on dialysis 37±29,6 months. Patients who had creatinine level greater than 2,5 mg/dl were excluded. Immunosuppressive therapy was based on basiliximab, steroids (1.6 to 2 mg/kg/day progressively reduced to 5 mg/day after 45 days from the transplantation) in all patients + calcineurin inhibitor+ mycophenolate mophetil/mycophenolic acid in 88,8% of patients or Everolimus± calcineurin inhibitor in the others. Patients were studied with X-ray of the spine, dual-energy-X-ray, PTH, 25(OH)VitD. Results: 41,1% had HPT; 41,1% had osteopenia at femoral neck and 36,7% at vertebral column; 16,7% had osteoporosis at femoral neck and 15,6% at vertebral column. 10 patients (11%) had vertebral fractures. Patients with normal bone mineral density, compared to those with osteoporosis/osteopenia, are more younger (average age 46,4±11,7 years vs 54.3±8,6); they have spent less time on dialysis (26,5±14,8 months vs 40,7±32,6) and they have values of 25(OH)VitD higher (22,1±7,6 ng/ml vs 17,8±8,5). Patients with vertebral fractures have values of 25(OH)VitD lowest (14,1±6,4 ng/ml vs 19,7±8,5) and they had transplant since more time (29,1±16,2 vs 48,1±8,7 months). There is a significant correlation between HPT and PTH pre transplantation; HPT and levels of VitD (p<0,05) Conclusion: Prevention of Bone disease and vertebral fractures after renal transplant includes: a)treatment before transplantation b)supplementation of vitamin D with cholecalciferol or calcidiol c)shorten the dialysis time.

Rare and complicated forms of infantile hemangiomas: new therapeutic outlooks

Infantile hemangiomas (IHs) are the most common benign neoplastic pathology of childhood; their natural history generally involves three phases: after the onset, which usually occurs in the first weeks of life, there is the proliferation phase where the IH reaches its maximum development and it is followed by the spontaneous involution which leads to the IH regression. The duration and the extent of these phases may vary widely even though in most of the cases the involution process begins around twelve months of life and the regression, complete or partial, is completed around seventh-ninth year of life. The majority of the IHs does not require any treatment. However, 10%-20% is likely to develop serious complications, functional impairments or aesthetic alterations and entail a timely treatment. Although there is no treatment protocol currently shared, therapies usually used in cases with a complication risk consist in: systemic or intralesional steroids as a first choice; interferon α, vincristine and/or bleomicin as second or third choice and/or surgical treatment. Propranolol, a non-selective beta-blocker, has been used for cardiovascular diseases even in childhood for decades. Since 2008 it has been widely used in the IHs treatment, although it is still "off-label". In literature there are hundreds of cases and some clinical studies that show the effectiveness and safety of this drug for this indication. Thanks to a multidisciplinary team (Dermatologists, Cardiologists, Paediatricians, and Radiologists) of S. Orsola-Malpighi Hospital, a clinical study, which has been previously approved by the ethics committee, is carried out in order to evaluate the efficacy and safety of systemic propranolol in the treatment of IHs in paediatric age. At the end of 2012, 78 patients underwent this treatment: the results we have obtained so far show a good efficacy and safety profile in agreement with the data provided by the literature.

Decorso delle coliti severe: un confronto tra colite ulcerosa e di Crohn

Pochi sono i dati disponibili sul decorso clinico della malattia di Crohn del colon severa(CD). L'obiettivo è quello di descrivere il decorso clinico della colite di Crohn severa (CC) in una coorte di pazienti isolata con CD del colon o ileocolica, e di confrontarlo con il decorso clinico di pazienti affetti da colite ulcerosa severa (UC). 34 pazienti con CC severa sono stati identificati retrospettivamente nella nostra coorte di 593 pazienti ricoverati (2003-2012) attraverso la valutazione di CDAI score e HBI. 169 pazienti con UC severa sono stati identificati retrospettivamente in una coorte di 449 pazienti ricoverati (2003-2012) attraverso la valutazione del score di Lichtiger e di Truelove-Witts. Abbiamo valutato questi risultati: risposta agli steroidi, risposta ai farmaci biologici, tasso di colectomia acuta, tasso di colectomia durante il follow-up, megacolon e tasso di infezione da citomegalovirus. Non abbiamo trovato differenze significative nella risposta agli steroidi e biologici, della percentuale di infezione da citomegalovirus e di megacolon, mentre il tasso di colectomia in acuto è risultato essere maggiore nei pazienti con CC rispetto ai pazienti con UC; anche la differenza tra i tassi di colectomia alla fine del follow-up è risultata non significativa. Con l'analisi univariata la giovane età alla diagnosi è associata ad un aumentato rischio di colectomia in assoluto (p = 0,024) e in elezione (p = 0.022), ma non in acuto. Il tasso globale di colectomia nei pazienti con CC severa è superiore a quella dei pazienti con UC severa , ma questo dato non è supportato da una diversa risposta clinica alla terapia steroidea o terapia di salvataggio con biologici. Il vero decorso clinico della colite di Crohn severa necessita di essere chiarito da studi prospettici che includano un numero maggiore di pazienti con questo sottogruppo di malattia.

Der Wirkungsmechanismus von Neurosteroiden auf das Cytoskelett neuronaler Zellen

Neurosteroide können langsame genomische und schnelle nicht-genomische Effekte zeigen. Die Synthese und der Metabolismus von Neurosteroiden werden entwicklungsbedingt reguliert. In den letzten Jahren sind immer mehr schnelle Steroideffekte bekannt geworden, die sowohl über klassische als auch über nicht-klassische Rezeptoren laufen. Zum heutigen Stand der Forschung sind die morphologischen Effekte von Neurosteroiden auf das neuronale Cytoskelett und die involvierten Signalkaskaden noch weitgehend unerforscht. In diesem Zusammenhang stellen sich auch die Fragen nach den verantwortlichen Rezeptoren und dem Transportmechanismus sowie der subzellulären Lokalisation der Steroide. Die im Rahmen meiner Promotion erhaltenen Ergebnisse zeigen, dass die Steroide DHEA und Testosteron eine Reorganisation des Aktincytoskeletts in neuronalen Zellen induzieren und dass diese Effekte diesen Steroiden und nicht ihren Folgemetaboliten zuzuordnen sind. DHEA bewirkt die Kontraktion der Zellen, eine erhöhte Ausbildung von Stressfasern und fokalen Adhäsionskomplexen sowie die Bildung von Filopodien. Der diesen Effekten zu Grunde liegende Signalweg konnte eindeutig identifiziert werden. DHEA induziert in neuronalen Zellen die Aktivierung des Rho-Signalwegs. Diese Aktivierung führt zu einem erhöhten Phosphorylierungsstatus der regulatorischen leichten Kette von Myosin II (MRLC) an Serin 19 und der damit verbundenen erhöhten Myosin-Aktin-Interaktion. Die Ausbildung von Filopodien wird vermutlich über eine Aktivierung der GTPase Cdc42 vermittelt. Testosteron induziert das Auswachsen langer Neuriten sowie eine Verminderung von Stressfasern in neuronalen Zellen. Diese Effekte sind abhängig von der Aktivität der PI3-Kinase. Die im Rahmen dieser Arbeit gewonnenen Erkenntnisse deuten darauf hin, dass Testosteron über die PI3-Kinase und FAK den Rac-Signalweg induziert, da es zu einer Inhibierung des Rho-Signalwegs kommt. Zahlreiche Erkenntnisse weisen darauf hin, dass DHEA und Testosteron die Aktivierung der beteiligten Signalwege über einen G-Protein gekoppelten Rezeptor induzieren. DHEA und Testosteron beeinflussen auch die Expression und die Lokalisation der regulatorischen leichten Ketten von Myosin II. Im Gegensatz zu DHEA (Lokalisation der MRLC in der kortikalen Region der Zelle), induziert Testosteron eine Umlokalisation der MRLC in den Zellkern. Daher ist es denkbar, dass die MRLCs, wie auch Aktin, als Transkriptionsfaktoren wirken können. Die Synthese eines funktionalen, fluoreszierenden DHEA-Derivats (DHEA-Bodipy) ermöglichte erstmals, den Transport und die subzelluläre Lokalisation von DHEA in neuronalen Zellen zu beobachten. DHEA-Bodipy wird in neuronalen Zellen in den Mitochondrien lokalisiert. Diese Lokalisation ergibt völlig neue Ansätze im Verständnis zellulärer Wirkungsorte von Steroiden und beteiligter Rezeptoren. Das in meiner Arbeit vorgestellte Verfahren zur Fluoreszenzmarkierung von Steroiden bietet vielfältige Möglichkeiten im Einsatz zellbiologischer Methoden. Nach diesem Verfahren hergestellte, fluoreszierende Steroide eignen sich aufgrund ihrer Stabilität sehr gut für die Untersuchung des Transports und der subzellulären Lokalisation von Steroiden an fixierten und lebenden Zellen sowie für Colokalisationsexperimente. Diese Methode grenzt somit auch die Anzahl möglicher molekularer Interaktionspartner ein. Für Testosteron konnte ebenfalls ein fluoreszierendes Testosteron-Derivat (Testosteron-Bodipy) synthetisiert werden. Die Aufklärung der Effekte von Steroiden auf das neuronale Cytoskelett und der beteiligten Signalkaskaden sowie die Identifizierung der zellulären Wirkungsorte ermöglichen therapeutische Ansätze zur Behandlung neurodegenerativer Erkrankungen, deren Ursachen in Abnormitäten des Cytoskeletts oder fehlregulierter Neurosteroidogenese zu begründen sind.

Controlled reproduction in Anguilla anguilla (L.): advanced studies on broodstock management, spawning techniques and system design for artificial seed production.

The thesis aims to expose the advances achieved in the practices of captive breeding of the European eel (Anguilla anguilla). Aspects investigated concern both approaches livestock (breeding selection, response to hormonal stimulation, reproductive performance, incubation of eggs) and physiological aspects (endocrine plasma profiles of players), as well as engineering aspects. Studies conducted on various populations of wild eel have shown that the main determining factor in the selection of wild females destined to captive breeding must be the Silver Index which may determine the stage of pubertal development. The hormonal induction protocol adopted, with increasing doses of carp pituitary extract, it has proven useful to ovarian development, with a synchronization effect that is positively reflected on egg production. The studies on the effects of photoperiod show how the condition of total darkness can positively influence practices of reproductions in captivity. The effects of photoperiod were also investigated at the physiological level, observing the plasma levels of steroids ( E2, T) and thyroid hormones (T3 and T4) and the expression in the liver of vitellogenin (vtg1 and vtg2) and estradiol membrane receptor (ESR1). From the comparison between spontaneous deposition and insemination techniques through the stripping is inferred as the first ports to a better qualitative and quantitative yield in the production of eggs capable of being fertilized, also the presence of a percentage of oocytes completely transparent can be used to obtain eggs at a good rate of fertility. Finally, the design and implementation of a system for recirculating aquaculture suited to meet the needs of species-specific eel showed how to improve the reproductive results, it would be preferable to adopt low-flow and low density incubation.

Fistole retto-vaginali Crohn-relate trattate mediante trasposizione del muscolo gracile: risultati a lungo termine e qualità della vita

OBIETTIVO: Le fistole retto-vaginali Crohn-relate hanno un impatto significativo sulla qualità della vita. Quando il canale anale è alterato da ulcerazioni e stenosi o in pazienti con difetti estesi del perineo, la chirurgia locale produce risultati insoddisfacenti. Lo scopo di questo studio è quello di valutare l'efficacia della trasposizione del muscolo gracile nelle fistole retto-vaginali Crohn-relate e determinare i suoi effetti sulla qualità della vita. MATERIALI E METODI: Da gennaio 2012 a ottobre 2014 sono state trattate 10 pazienti; sono state raccolte alcune variabili (età, BMI, il fumo, CDAI, setone perioperatorio, precedenti procedure, uso di immunomodulatori e steroidi). Tutte le pazienti sono state sottoposte ad ileostomia temporanea prima della graciloplastica. La percentuale di successo è stata misurata come numero di pazienti con fistola guarita dopo la chiusura della stomia. Sono stati utilizzati tre questionari prima della graciloplastica e 3 mesi dopo la chiusura della stomia al fine di valutare la qualità della vita (SF-36), l’ incontinenza fecale e la funzione sessuale. RISULTATI: La fistola retto-vaginale è stata chiusa in 9 pazienti su 10 dopo graciloplastica, con un follow-up medio di chiusura della stomia di 19 mesi (range 4 -34). È stata documentata una recidiva di RVF. Il tempo operatorio era 90-150 minuti (media, 120). La degenza postoperatoria era 7-16 giorni (media 10). Complicanze postoperatorie precoci includevano deiscenza delle suture perineali in 2 casi. Le complicanze a lungo termine includevano disestesia della cicatrice perineale. Nei dati post-operatori abbiamo riportato un miglioramento della qualità di vita, della funzione sessuale e della continenza fecale. CONCLUSIONI: La chiusura della fistola retto-vaginale utilizzando la trasposizione del muscolo gracile è associata a morbidità minima e un alto tasso di successo.

Synthetic studies towards a new fulvestrant analogue

A study towards the synthesis of a new fulvestrant analogue with improved bioavailability was carried out. In this work a twelve-step synthetic route starting from β-estradiol was optimized and a palladium (Pd)-catalyzed endo-selective Heck reaction for the functionalization of an advanced intermediate was investigated.

Retrospective comparison of maternal vs. HPA-matched donor platelets for treatment of fetal alloimmune thrombocytopenia

In fetal alloimmune thrombocytopenia (FAIT), transplacental maternal antibodies cause destruction of fetal platelets. FAIT is similar to fetal Rhesus haemolytic disease, but half of the affected fetuses are born to primiparous women. In 10-20% of cases, prenatal and perinatal intracranial haemorrhages are reported. Different therapeutic approaches have been described, including maternally administered high-dose intravenous immunoglobulin (high dose IVIG) without or with steroids or intrauterine transfusion (IUT) of compatible platelets. For the latter, the use of plasma-free maternal and donor platelets has been described, but a comparison of these two sources of platelets has not been reported.

Eosinophilic vasculitis: an inhabitual and resistant manifestation of a vasculitis

A 55-year-old woman was referred because of diffuse pruritic erythematous lesions and an ischemic process of the third finger of her right hand. She was known to have anaemia secondary to hypermenorrhea. She presented six months before admission with a cutaneous infiltration on the left cubital cavity after a paravenous leakage of intravenous iron substitution. She then reported a progressive pruritic erythematous swelling of her left arm and lower extremities and trunk. Skin biopsy of a lesion on the right leg revealed a fibrillar, small-vessel vasculitis containing many eosinophils.Two months later she reported Raynaud symptoms in both hands, with a persistent violaceous coloration of the skin and cold sensation of her third digit of the right hand. A round 1.5 cm well-delimited swelling on the medial site of the left elbow was noted. The third digit of her right hand was cold and of violet colour. Eosinophilia (19 % of total leucocytes) was present. Doppler-duplex arterial examination of the upper extremities showed an occlusion of the cubital artery down to the palmar arcade on the right arm. Selective angiography of the right subclavian and brachial arteries showed diffuse alteration of the blood flow in the cubital artery and hand, with fine collateral circulation in the carpal region. Neither secondary causes of hypereosinophilia nor a myeloproliferative process was found. Considering the skin biopsy results and having excluded other causes of eosinophilia, we assumed the diagnosis of an eosinophilic vasculitis. Treatment with tacrolimus and high dose steroids was started, the latter tapered within 12 months and then stopped, but a dramatic flare-up of the vasculitis with Raynaud phenomenon occurred. A new immunosuppressive approach with steroids and methotrexate was then introduced. This case of aggressive eosinophilic vasculitis is difficult to classify into the usual forms of vasculitis and constitutes a therapeutic challenge given the resistance to current immunosuppressive regimens.

[Spontaneous hematomas and isolated prolongation of aPTT]

We report a case of a 64 year old woman with spontaneous hematomas. A prior history of bleeding disorder was not known up to now. The result of investigation of coagulation was an isolated prolonged aPTT that was caused by an inhibitor of factor VIII without underlying disease (idiopathic acquired hemophilia A). Therapy with steroids and cyclophosphamid resulted in partial remission.

Differential effects of dexamethasone on the chondrogenesis of mesenchymal stromal cells: influence of microenvironment, tissue origin and growth factor

Mesenchymal stromal cells (MSCs), which reside within various tissues, are utilized in the engineering of cartilage tissue. Dexamethasone (DEX)--a synthetic glucocorticoid--is almost invariably applied to potentiate the growth-factor-induced chondrogenesis of MSCs in vitro, albeit that this effect has been experimentally demonstrated only for transforming-growth-factor-beta (TGF-β)-stimulated bone-marrow-derived MSCs. Clinically, systemic glucocorticoid therapy is associated with untoward side effects (e.g., bone loss and increased susceptibility to infection). Hence, the use of these agents should be avoided or limited. We hypothesize that the influence of DEX on the chondrogenesis of MSCs depends upon their tissue origin and microenvironment [absence or presence of an extracellular matrix (ECM)], as well as upon the nature of the growth factor. We investigated its effects upon the TGF-β1- and bone-morphogenetic-protein 2 (BMP-2)-induced chondrogenesis of MSCs as a function of tissue source (bone marrow vs. synovium) and microenvironment [cell aggregates (no ECM) vs. explants (presence of a natural ECM)]. In aggregates of bone-marrow-derived MSCs, DEX enhanced TGF-β1-induced chondrogenesis by an up-regulation of cartilaginous genes, but had little influence on the BMP-2-induced response. In aggregates of synovial MSCs, DEX exerted no remarkable effect on either TGF-β1- or BMP-2-induced chondrogenesis. In synovial explants, DEX inhibited BMP-2-induced chondrogenesis almost completely, but had little impact on the TGF-β1-induced response. Our data reveal that steroids are not indispensable for the chondrogenesis of MSCs in vitro. Their influence is context dependent (tissue source of the MSCs, their microenvironment and the nature of the growth-factor). This finding has important implications for MSC based approaches to cartilage repair.

Evidence-based management of bullous pemphigoid

Bullous pemphigoid (BP) is the most common autoimmune subepidermal bullous disease typically affecting the elderly. Although different therapeutic regimens have been proposed, a review of the evidence is needed to aid clinicians in their decision making and management. Systemic therapies such as corticosteroids and adjuvants are effective in BP but are plagued with adverse effects, and potent topical steroids are an alternative treatment. This article reviews the evidence supporting different therapeutic options in the management of BP.