A synergic approach of X-ray powder diffraction and Raman spectroscopy for crystal structure determination of 2,3-thienoimide capped oligothiophenes.

This work presents a Raman based approach for the rapid identification of the molecular conformation in a series of new 2,3-thienoimide capped quaterthiophenes, whose crystal structures were determined by synchrotron radiation X-ray powder diffraction. These systems display two conformational polymorphs, known as forms A and B, as a result of the anti-anti-anti and syn-anti-syn arrangements of the quaterthiophene cores. In a micro-Raman and computational study, the spectroscopic differences between the conformers were detected and proved to be suitable markers for polymorph identification. Thus, the synergic employment of diffraction and Raman spectroscopy techniques yields a full and reliable characterization of 2,3-thienoimide capped quaterthiophene compounds in their solid state.

Biomimetic graphene for enhanced interaction with the external membrane of astrocytes.

Graphene and graphene substrates display huge potential as material interfaces for devices and biomedical tools targeting the modulation or recovery of brain functionality. However, to be considered reliable neural interfaces, graphene-derived substrates should properly interact with astrocytes, favoring their growth and avoiding adverse gliotic reactions. Indeed, astrocytes are the most abundant cells in the human brain and they have a crucial physiological role to maintain its homeostasis and modulate synaptic transmission. In this work, we describe a new strategy based on the chemical modification of graphene oxide (GO) with a synthetic phospholipid (PL) to improve interaction of GO with brain astroglial cells. The PL moieties were grafted on GO sheets through polymeric brushes obtained by atom-transfer radical-polymerization (ATRP) between acryloyl-modified PL and GO nanosheets modified with a bromide initiator. The adhesion of primary rat cortical astrocytes on GO-PL substrates increased by about three times with respect to that on glass substrates coated with standard adhesion agents (i.e. poly-d-lysine, PDL) as well as with respect to that on non-functionalized GO. Moreover, we show that astrocytes seeded on GO-PL did not display significant gliotic reactivity, indicating that the material interface did not cause a detrimental inflammatory reaction when interacting with astroglial cells. Our results indicate that the reported biomimetic approach could be applied to neural prosthesis to improve cell colonization and avoid glial scar formation in brain implants. Additionally, improved adhesion could be extremely relevant in devices targeting neural cell sensing/modulation of physiological activity.

Interaction of graphene-related materials with human intestinal cells: an in vitro approach.

Graphene-related materials (GRM) inherit unique combinations of physicochemical properties which offer a high potential for technological as well as biomedical applications. It is not clear which physicochemical properties are the most relevant factors influencing the behavior of GRM in complex biological environments. In this study we have focused on the interaction of GRM, especially graphene oxide (GO), and Caco-2 cells in vitro. We mimiked stomach transition by acid-treatment of two representative GRM followed by analysis of their physicochemical properties. No significant changes in the material properties or cell viability of exposed Caco-2 cells in respect to untreated GRM could be detected. Furthermore, we explored the interaction of four different GO and Caco-2 cells to identify relevant physicochemical properties for the establishment of a material property-biological response relationship. Despite close interaction with the cell surface and the formation of reactive oxygen species (ROS), no acute toxicity was found for any of the applied GO (concentration range 0-80 µg ml(-1)) after 24 h and 48 h exposure. Graphene nanoplatelet aggregates led to low acute toxicity at high concentrations, indicating that aggregation, the number of layers or the C/O ratio have a more pronounced effect on the cell viability than the lateral size alone.

Solution-phase microwave-assisted synthesis of unsubstituted and modified alpha-quinque- and sexithiophenes.

The facile synthesis of poorly soluble unsubstituted and modified alpha-quinque- and sexithiophenes under microwave irradiation in the liquid phase is described. The use of microwave irradiation allowed these compounds to be prepared in a few minutes and at high yields by means of the Suzuki cross-coupling reaction. Unsubstituted sexithiophene was obtained in 10 min via the one-pot borylation/Suzuki reaction, purified according to a very simple procedure, and isolated in 84% yield. The efficient synthesis of two new methylated quinque- and sexithiophenes displaying liquid crystalline properties is reported. A new microwave-assisted methodology for the conversion of aldehyde-terminated quinque- and sexithiophenes into the corresponding cyano derivatives is also described. The use of microwaves was extended to the Sonogashira coupling reaction and found to be very effective in the preparation of a quinquethiophene containing acetylenic spacers. The electronic and optical characterization of this compound is reported and discussed in relation to that of unsubstituted quinquethiophene.

An assessment of factors related to tumor thickness and delay in diagnosis of melanoma in southern Italy.

BACKGROUND: Since survival of patients with melanoma is strongly correlated with the Breslow tumor thickness of the primary lesion, factors that influence stage at diagnosis and delay in diagnosis are considered to be crucial. To test the relationship between tumor thickness and some social and clinical variables (including diagnosis/treatment delay) and the relationship between the diagnosis/treatment delay and some clinical variables, we analyzed data on 530 patients with melanoma from our Institute. METHODS: In the analysis, Breslow tumor thickness was categorized into two categories (< or =1.49, > or =1.5). Three time intervals were examined to evaluate diagnostic delay: patient delay, time from first symptom to seeking medical advice; medical delay, time from first medical consultation to hospital admission; total delay, time from first symptom to resection. The variables evaluated in the analysis were: age at diagnosis, education, occupational status, first symptom, visibility of tumor, anatomic site, and physician who made the initial diagnosis. RESULTS: A significant risk of having a Breslow tumor thickness > or =1.5 mm was noted in patients who had a low level of education (odds ratio 3.0, 95% confidence interval 1.9-5.0) or who were unemployed (odds ratio 1.7, 95% confidence interval 1.1-2.8). With respect to patient delay, a delay >3 months for anatomic locations visible to patients was associated with significant risk (odds ratio 1.7, 95% confidence interval 1.1-2.6); with respect to medical delay, a delay >3 months was associated with a higher risk in patients examined by a dermatologist (odds ratio 2.0, 95% confidence interval 1.2-3.4). CONCLUSIONS: Our results clearly indicate that in Southern Italy poorly educated and unemployed subjects are at risk of being diagnosed at a more advanced stage, and admission to an oncological hospital causes a delay (waiting list) in the time interval related to the doctor (medical delay).

Intermediate dose recombinant interferon-alpha as second-line treatment for patients with recurrent cutaneous melanoma who were pretreated with low dose interferon.

BACKGROUND: Interferon (IFN) is widely considered the most effective agent in the adjuvant therapy of patients with cutaneous melanoma (CM). However, little is known about the effect of IFN on pretreated CM patients who experience disease recurrence. The authors conducted a Phase II study to determine whether intermediate doses of IFN could be beneficial for these patients. METHODS: A series of 24 consecutive CM patients who had undergone surgery for local, in-transit, or lymph node disease recurrence during adjuvant therapy with low dose IFN (IFNalpha-2b, 3 million units [MU] per day, three times per week) were enrolled for second-line therapy with intermediate dose IFN (IFNalpha-2b, 10 MU per day) for one year. RESULTS: IFN was discontinued in 7 patients (29.2%) because of toxicity. Several patients complained of impairment in their daily activities. Progression of disease was registered in 17 patients (70. 8%), with a median disease free survival of 5.5 months (95% confidence interval, 3.4-14.2). The median follow-up for the 7 patients who did not experience disease recurrence was 15 months (range, 13-22 months). CONCLUSIONS: An increased dose of IFN as second-line adjuvant treatment was poorly tolerated and produced negative clinical outcomes in patients with CM. However, these patients probably were unresponsive to IFN regardless of the dosage level. In fact, the first adjuvant IFN treatment was ineffective in all patients. Thus, the key factor in the treatment of CM seems to be patient responsiveness to IFN rather than the total dosage achieved.

Sensitivity and specificity of epiluminescence microscopy: evaluation on a sample of 2731 excised cutaneous pigmented lesions. The Melanoma Cooperative Study.

To evaluate the role of epiluminescence microscopy (ELM) in the differential diagnosis of cutaneous pigmented lesions, and to improve the early diagnosis of cutaneous malignant melanoma (CMM), 15,719 pigmented lesions from 8782 consecutive patients were evaluated using ELM with a hand-held video microscope imaging system (MS 500B Micro-Scopeman, Moritex). Comparison between risk levels as inferred from ELM screening and histology was performed on 2731 surgically excised lesions. ELM sensitivity, specificity, positive and negative predictive values, as well as agreement with histological results for the different subgroups of lesions, were determined. Overall agreement was 87.3% (ranging from 85.1% to 92.2% for melanocytic and non-melanocytic lesions, respectively); sensitivity and specificity were high (values ranging from 87.3% to 96.3% among different subsets of ELM-analysed lesions) and statistically significant (P < 0.0001). ELM screening identified 165 new cases of CMM with a high proportion of lesions (115; 70%) in an early phase of tumour growth (Breslow thickness

Cisplatin, dacarbazine, and fotemustine plus interferon alpha in patients with advanced malignant melanoma. A multicenter phase II study of the Italian Cooperative Oncology Group.

BACKGROUND: In a previous study, the authors tested the combination of fotemustine (FM) 100 mg/m(2) intravenously (i.v.) on Day 1, dacarbazine (DTIC) 250 mg/m(2) i.v. on Days 2-5, and interferon alpha (IFNalpha) 3 MIU intramuscularly three times per week in 43 patients with advanced melanoma. An overall response rate of 40% and a median survival of 40 weeks were obtained. To evaluate whether the addition of cisplatin (CDDP) to this regimen could improve these results, the authors conducted a preliminary Phase I study and concluded that CDDP 25 mg/m(2) i.v. for 2 days can be combined safely with DTIC, FM, and IFNalpha. Herein, the authors report the results of a Phase II trial with this regimen. METHODS: From June 1996 to February 1999, 64 patients with metastatic melanoma who were not amenable to surgery were enrolled in this study. Sixty eligible patients (32 males and 28 females; median age, 53 years) were treated with a combination of FM 100 mg/m(2) i.v. on Day 1, DTIC 300 mg/m(2) i.v. on Days 2-4, and CDDP 25 mg/m(2) i.v. on Days 3 and 4 recycled every 3 weeks. IFN alpha2b was administered at a dose of 3 MIU intramuscularly 3 times per week until disease progression. RESULTS: A total of 189 courses were administered, with a median number of 3 courses per patient (range, 1-8 courses per patient). Eleven complete responses and 12 partial responses were observed, for an overall response rate of 38.3% (95% exact confidence interval, 26.1-51.8%). The median survival was 36 weeks. Neutropenia and thrombocytopenia affected 85% of patients and 68% patients and was World Health Organization Grade 3-4 in 40% and 50%, respectively. The side effects attributable to IFN alpha2b were mild and manageable. The other side effects were moderate and well controlled by supportive therapy. CONCLUSIONS: The schedule used in this study demonstrated significant activity in patients with advanced, untreated melanoma. The addition of CDDP in the management of the patients in this series seemed to increase significantly both the proportion of patients who achieved a complete response and the probability of long term survival compared with a previous series of patients who were treated by the authors. However, considering the currently available therapies, this regimen does not seem to offer a special advantage in the treatment of patients with this disease. New agents and new protocols are needed.