Tuning the sensitivity of lanthanide-activated NIR nanothermometers in the biological windows

Lanthanide-activated SrF₂ nanoparticles with a multishell architecture were investigated as optical thermometers in the biological windows. A ratiometric approach based on the relative changes in the intensities of different lanthanide (Nd³⁺ and Yb³⁺) NIR emissions was applied to investigate the thermometric properties of the nanoparticles. It was found that an appropriate doping with Er³⁺ ions can increase the thermometric properties of the Nd³⁺-Yb³⁺ coupled systems. In addition, a core containing Yb³⁺ and Tm³⁺ can generate light in the visible and UV regions upon near-infrared (NIR) laser excitation at 980 nm. The multishell structure combined with the rational choice of dopants proves to be particularly important to control and enhance the performance of nanoparticles as NIR nanothermometers.

Nucleation, Growth Mechanism, and Controlled Coating of ZnO ALD onto Vertically Aligned N-Doped CNTs

Zinc oxide thin films were deposited on vertically aligned nitrogen-doped carbon nanotubes (N-CNTs) by atomic layer deposition (ALD) from diethylzinc and water. The study demonstrates that doping CNTs with nitrogen is an effective approach for the "activation" of the CNTs surface for the ALD of metal oxides. Conformal ZnO coatings are already obtained after 50 ALD cycles, whereas at lower ALD cycles an island growth mode is observed. Moreover, the process allows for a uniform growth from the top to the bottom of the vertically aligned N-CNT arrays. X-ray photoelectron spectroscopy demonstrates that ZnO nucleation takes place at the N-containing species on the surface of the CNTs by the formation of the Zn-N bonds at the interface between the CNTs and the ZnO film.

A randomized trial of intensive versus minimal surveillance of patients with resected Dukes B2-C colorectal carcinoma

BACKGROUND

Colorectal cancer is the third most common and the third most lethal cancer in both men and women in developed countries. About 75% of cases are first diagnosed when the disease is classified as localized or regional, undergo potentially curative treatment and enter a post-treatment surveillance program. Although such programs drain significant resources from health systems, empirical evidence of their efficacy is scanty.

PATIENTS AND METHODS

Dukes B2-C colorectal cancer patients who had no evidence of disease at the end of their front-line treatment (surgery and adjuvant radiochemotherapy, if indicated) were eligible for the trial and randomized to two different surveillance programs. These programs differed greatly in the frequency of diagnostic imaging. They had similar schedules of physical examinations and carcinoembryonic antigen (CEA) assessments. Patients received baseline and yearly health-related quality-of-life (HR-QoL) questionnaires. Primary outcomes were overall survival (OS) and QoL.

RESULTS

From 1998 to 2006, 1228 assessable patients were randomized, 933 with colon cancer and 295 with rectal cancer. More than 90% of patients had the expected number of diagnostic procedures. Median follow-up duration was 62 months [interquartile range (IQR) 51-86] in the minimal surveillance group and 62 months (IQR 50-85) in the intensive group. At primary analysis, 250 patients had recurred and 218 had died. Intensive surveillance anticipated recurrence, as shown by a significant difference in mean disease-free survival of 5.9 months. Comparison of OS curves of the whole intention-to-treat population showed no statistically significant differences. HR-QoL of life scores did not differ between regimens.

CONCLUSION

Our findings support the conclusions of other randomized clinical trials, which show that early diagnosis of cancer recurrence is not associated with OS benefit.

CLINICALTRIALSGOV

NCT02409472.

A general nonaqueous route to crystalline alkaline earth aluminate nanostructures

A nonaqueous route based on the solvothermal reaction of alkaline earth precursors with aluminium isopropoxide in benzyl alcohol is introduced. This simple process leads to crystalline complex nanostructures of alkaline earth aluminates, which, up to now, could only be obtained by solid state reaction at temperatures above 1100 degrees C or by sol-gel and further calcination at temperatures only slightly lower ( approximately 800 degrees C). The approach appears to be rather general since under the same reaction conditions BaAl(2)O(4), CaAl(4)O(7), and SrAl(4)O(7) could be obtained. The as-synthesized materials were characterized by X-ray diffraction, electron microscopy techniques, solid-state NMR and FT-IR spectroscopies. The reaction mechanism, which was studied as well, indicates the in-situ formation of benzoate species. These can preferentially bind to particular crystallographic facets of the aluminates via bridging bonds, thereby stabilizing the surfaces that give rise to the peculiar complex structure of the final material. In order to supplement the synthesis approach and to investigate the formation of impurity phases, pure aluminium oxide hybrid nanostructures were synthesized under similar conditions and fully characterized.

Synthesis, antiviral and antiproliferative activity of a new class of 5-(alkyl or arylthio)-6-vinyl uracils

Uracil derivatives bearing substituted or unsubstituted vinyl groups at position C6 and alkyl- or arylthio groups at position C5 were synthesized and tested in vitro for antiviral and antiproliferative activity. None of the compounds were active against HIV-1. However, some of them inhibited the proliferation of leukemia, lymphoma and solid tumor-derived cell lines at micromolar concentrations. The maximum potency of antiproliferative activity correlates with the presence of unsubstituted vinyl groups and alkyl- or arylthio substituents.

3,6-Disubstituted 1,2,4-triazolo[3,4-b][1,3,4]thiadiazoles: synthesis, antimicrobial and antiviral activity. II

A series of novel 3,6-disubstituted 1,2,4-triazolo[3,4-b][1,3,4] thiadiazole derivatives was prepared and tested to evaluate their antimycotic and antibacterial activities. Anti-HIV-1 activity has also been investigated. Among the test compounds, derivatives 10a-14a and 16c showed anti-HIV-1 activity at concentrations slightly below those cytotoxic. Substitutions at 3 and 6 positions seems to be important in lowering the cytotoxicity of compounds.

Fibronectin, cholesterol and triglycerides ascitic fluid concentration in the prediction of malignancy

There have been few trials comparing the efficacy of determinations of cholesterol, fibronectin and triglycerides for diagnosis of malignant ascites. In this study we measured these in 200 ascitic fluids from 93 cirrhotic patients (Group A), 47 hepatocellular-carcinoma patients (Group B), 60 extra-hepatic tumour patients (Group C), 44 of them with malignant cells (Group Cpos) and 16 without (Group Cneg). Anova one-way and the Bonferroni test for multiple comparisons showed that fibronectin and cholesterol were significantly higher in the ascitic fluids of patients of group C than of groups A and B (mean +/- ESM) (Cholesterol in A: 27.2 +/- 2.8; in B 23.5 +/- 1.5; in C: 68.6 +/- 5.3 mg/dl. Fibronectin in A: 32.7 +/- 2.8; in B 31.3 +/- 2.6; in C 127.7 +/- 11.1 mg/l). Both were significantly higher in Group Cpos than in Group Cneg (Cholesterol in Cneg: 41.2 +/- 6.7; in Cpos: 78.6 +/- 6.2 mg/dl. Fibronectin in Cneg: 55.0 +/- 11.2; in Cpos 154 +/- 12.3 mg/dl). We found no differences between cirrhotic ascites and malignant ascites due to primary liver hepatocellular-carcinoma. No difference at all in triglycerides were detected. With the Receiver-Operating Characteristic (ROC) curve, cholesterol had the best Youden Index (57%) at a cut-off of 32 mg/dl (sensitivity 78.3%, specificity 79.3% at this level); the best Youden Index (64%) for fibronectin had a cut-off of 60 mg/dl (sensitivity 65%, specificity 89.3%). Triglycerides appeared to be a great deal less effective as a diagnostic marker, with their best Youden Index (23%) at a cut-off 32 mg/dl (sensitivity 66.7%, specificity 56.4%).(ABSTRACT TRUNCATED AT 250 WORDS)

Correlation between histochemically assessed hormonal receptor content and clinical course in breast cancer. Presentation of 1,005 cases

Lee's histochemical method was used to assess hormonal receptors in 1,005 patients with breast cancer. Patients were from 8 oncological departments in northern Italy. The group was subdivided into four subgroups in relation to menopausal status and presence or absence of axillary node metastasis. Overall survival (OS) and disease-free survival (DFS) were analysed in all subgroups in relation to receptorial status. We observed: (1) when hormonal receptors are present, OS and DFS are longer in all subgroups; (2) the presence of hormonal receptors influences favourably both DFS and OS, but it seems to play a more important role for DFS; (3) the positive receptorial status is a better prognostic factor in groups without axillary node metastasis, especially in premenopausal patients. We conclude that the histochemical assessment of hormonal receptors is a valid method for the prognostic evaluation of patients with breast cancer.