Erika Varga

Detection of Merkel cell polyomavirus DNA in Merkel cell carcinomas

Background  Merkel cell carcinoma (MCC) is a rare, aggressive tumour for which an increasing incidence has been reported. A new human polyomavirus, Merkel cell polyomavirus (MCV), was recently isolated from these tumours by applying digital transcriptome subtraction methodology.

Comparative solution equilibrium studies of anticancer gallium(III) complexes of 8-hydroxyquinoline and hydroxy(thio)pyrone ligands

The stoichiometry and stability constants of the Ga(III) complexes of 8-hydroxyquinoline (HQ), 8-hydroxyquinoline-5-sulfonate (HQS), maltol, thiomaltol, allomaltol and thioallomaltol were determined by means of pH-potentiometry, UV-vis spectrophotometry, spectrofluorometry and (1)H NMR spectroscopy in aqueous solution. Spectrofluorometry was used to determine the stability constants of the Ga(III)-HQ species in water. Formation of [GaL](2+), [GaL(2)](+) and [GaL(3)] complexes was found and the Ga(III) binding ability of the ligands followed the order: thioallomaltol<thiomaltol<allomaltol<maltol≪HQS~HQ. As a result of the outstanding stability of tris(8-hydroxyquinolinato)gallium(III) (KP46) the dissociation of the complex is negligible at physiological pH even in the biologically relevant low concentration range. Thus KP46 is able to preserve its original entity more considerably than other Ga(III) complexes. Moreover, intrinsic fluorescence of KP46 allows the monitoring of the cellular accumulation and distribution in human cancer cells by fluorescence microscopy.

Neglected Basal cell carcinomas in the 21st century.

Although tumors on the surface of the skin are considered to be easily recognizable, neglected advanced skin neoplasms are encountered even in the 21st century. There can be numerous causes of the delay in the diagnosis: fear of the diagnosis and the treatment, becoming accustomed to a slowly growing tumor, old age, a low social milieu, and an inadequate hygienic culture are among the factors leading some people not to seek medical advice. The treatment of such advanced neoplasms is usually challenging. The therapy of neglected cases demands an individual multidisciplinary approach and teamwork. Basal cell carcinoma (BCC), the most common cutaneous tumor, usually develops in the elderly, grows slowly, and has an extremely low metastatic potential; these factors are suggesting that BCCs might well be the “ideal candidates” for neglected tumors. Five neglected advanced cases of BCC were diagnosed in our dermatological institute between 2000 and 2009. The clinical characteristics and treatment modalities of these neoplasms are discussed, together with the possible causes of the neglect.

Influence of gold additives on the stability and phase transformation of titanate nanostructures

Gold nanoparticles were prepared and characterized on protonated (H-form) titanate nanotubes (TiONTs) and nanowires (TiONWs). The chemical nature and morphology of gold particles were monitored by X-ray photoelectron spectroscopy (XPS), Raman spectroscopy, X-ray diffraction (XRD) and high resolution electron microscopy (HRTEM). The optical properties of Au-containing titanate nanowires were explored by means of ultraviolet-visible diffuse reflectance spectroscopy. The size distribution and homogeneity of gold particles depend on the reduction mode from the corresponding gold salt to metal particles. Smaller clusters (3-8 nm) were obtained with the NaBH4 reactant at 293 K than with molecular hydrogen reduction. An unexpectedly high binding energy gold state was found by XPS in gold-loaded titanate nanostructures. This state was absent from the spectra of gold-loaded TiO2(110). A likely explanation for this phenomenon, supported also by the characteristic decrease of band gap energy from 3.10 eV to 2.74 eV with increasing Au content, is that depending on the metal loading and titanate structure, Au is stabilized on titanate nanowires partially in positively charged gold form by ion exchange and also as Au clusters. Our important new finding is that the thermal annealing behavior of Au-loaded titanate nanotubes and nanowires is different. The former lose their tubular morphology and are readily transformed into anatase even at a very low temperature of 473 K. On the other hand, gold stabilizes the layered structure of titanate nanowires up to 873 K.

Melanoma and melanocytic nevi in decorative tattoos: three case reports.

Background: In response to the demands of style and fashion, the number of decorative tattoos has been increasing worldwide. This has been paralleled by a rising incidence of melanocytic proliferations, including melanoma. The coincidence of various dermatological diseases and skin tumors with tattoos has been documented with some frequency, but reports of melanoma associated with tattoos are exceedingly rare. To date, only 13 cases have been documented in the English language literature. The possibility of an association between melanocytic proliferations and tattoos remains an area for further study.

Probing the interaction of Rh, Co and bimetallic Rh–Co nanoparticles with the CeO2 support: catalytic materials for alternative energy generation

The interaction of CeO2-supported Rh, Co and bimetallic Rh-Co nanoparticles, which are active catalysts in hydrogen production via steam reforming of ethanol, a process related to renewable energy generation, was studied by X-ray diffraction (XRD), high resolution electron microscopy (HRTEM), X-ray photoelectron spectroscopy (XPS) and low energy ion scattering (LEIS). Furthermore, diffuse reflectance infrared spectroscopy (DRIFTS) of adsorbed CO as a probe molecule was used to characterize the morphology of metal particles. At small loadings (0.1%), Rh is in a much dispersed state on ceria, while at higher contents (1-5%), Rh forms 2-8 nm particles. Between 473-673 K pronounced oxygen transfer from ceria to Rh is observed and at 773 K significant agglomeration of Rh occurs. On reduced ceria, XPS indicates a possible electron transfer from Rh to ceria. The formation of smaller ceria crystallites upon loading with Co was concluded from XRD and HRTEM; for 10% Co, the CeO2 particle size decreased from 27.6 to 10.7 nm. A strong dissolution of Co into ceria and a certain extent of encapsulation by ceria were deduced by XRD, XPS and LEIS. In the bimetallic system, the presence of Rh enhances the reduction of cobalt and ceria. During thermal treatments, reoxidation of Co occurs, and Rh agglomeration as well as oxygen migration from ceria to Rh are hindered in the presence of cobalt.

BRAFV600E mutation in cutaneous lesions of patients with adult Langerhans cell histiocytosis

Langerhans cell histiocytosis (LCH) is characterized by the proliferation of pathologic Langerhans cells. The disease can develop in any age and can affect almost any organ. Cutaneous involvement is frequent in LCH. The recent demonstration of the activating, oncogenic BRAFV600E gene mutation in LCH samples strongly supports the neoplastic origin of the disease.

Successful treatment of multiple basaliomas with bleomycin-based electrochemotherapy: a case series of three patients with Gorlin-Goltz syndrome.

Gorlin-Goltz syndrome is a rare multisystemic disease, characterized by numerous basal cell carcinomas. The ideal approach for patients with the syndrome would be a treatment with a high cure rate, minimal scarring, short healing time and mild side-effects. Electrochemo-therapy is a novel therapeutic option that ablates tumours with electrical current and simultaneously administered anticancer drugs. Three patients with Gorlin-Goltz syndrome were treated with electrochemotherapy using intravenous bleomycin. Clinical response was obtained in 98 (99%) of the lesions, 86 (87%) of them showed complete response. In 2 tumours, regression was confirmed with histological examination. Long-term cosmetic results were excellent. We consider electrochemotherapy to be an additional tool in the therapeutic armamentarium for Gorlin-Goltz syndrome, and suggest using it as early as possible in selected patients to avoid disfiguring scarring.

Strontium ranelate-induced DRESS syndrome with persistent autoimmune hepatitis

A relatively new drug used in the treatment of osteoporosis, strontium ranelate has been associated with several side effects, including increased relative risk of venous thromboembolism (including pulmonary embolism), transient increases in creatine kinase levels, mild gastrointestinal, nervous system and muscular disorders, and drug-induced hypersensitivity syndrome, also called DRESS syndrome (1). DRESS syndrome is a severe, acute drug reaction defined by the presence of fever, skin eruptions and systemic symptoms, including enlarged lymph nodes, abnormal liver function, renal impairment, and pulmonary and cardiac infiltrates, as well as haematological abnormalities, primarily hypereosinophilia and lymphocytosis (2, 3). We report here a case of a patient with strontium ranelate-induced DRESS who developed persistent autoimmune hepatitis.

Stability and Temperature-Induced Agglomeration of Rh Nanoparticles Supported by CeO2

The effects of reduction by H2 and by heat treatment in vacuum and in O2 flow on Rh particle size changes of Rh/CeO2 samples were studied by X-ray photoelectron spectroscopy (XPS), high-resolution electron microscopy (HRTEM), and CO adsorption followed by diffuse reflectance infrared spectroscopy (DRIFTS). Low-temperature (373-423 K) reduction of Rh without agglomeration is demonstrated. An average particle size of 2.3 ± 1.1 nm was measured by HRTEM regardless of the metal loading (1-5%). On Rh/CeO2, a significant particle size increase of the Rh particles was detected on heating (773 K). In this work, we suggest that the temperature-induced surface decrease resulting from the sintering of Rh is favored only for well-dispersed particles. XP spectra revealed that the mobile oxygens of CeO2 fundamentally determine the oxidation state of the supported metals. At elevated temperature, the oxidation of the reduced support surface as well as the metal component takes place because of the segregation of ceria oxygens. When the aggregated particles were reoxidized, the redispersion of Rh was observed probably because of the formation of Rh-O-Ce bonds.