Regional trends in Portuguese gastric cancer mortality (1984-1999).

The international decline in gastric cancer is mainly attributed to improved socio-economic conditions. However, some southern and eastern European countries showed slower and later decline, reflecting a less favourable general environment The same probably applies to regional differences within countries, making national indicators potentially misleading. Fitting log-linear Poisson models we compared trends in gastric cancer mortality (1984-1999) across 18 Portuguese regions. Pearson correlation coefficients were computed to assess the regional association between decline in cancer mortality and baseline cancer mortality and variation in indices of social development and medical care. National gastric cancer mortality changed -2.0% year in men and -2.2% year in women. The regional yearly variation in mortality ranged from -3.5% [95% confidence interval (CI) -4.5 to -2.5] to -0.6% (95% CI -1.4 to 0.2) in men, and from -3.7% (95% CI -4.8 to -2.7) to -0.8% (95% CI -1.6 to 0.0) in women. Regional variation was not significantly associated with baseline gastric cancer mortality (r = 0.18, P = 0.47), but with the variation in post-neonatal mortality (r = 0.59, P = 0.01). In Portugal, gastric cancer shows a wide regional variation in frequency trends. The correlation with known indicators of social and economic development indicates that future improvement in gastric cancer rates is expected in parallel with a more widespread development.     

Opioid-based micro and nanoparticulate formulations: alternative approach on pain management

Context Opioids have been used as the reference treatment on chronic pain. However, they are related to serious adverse effects which affect the patient compliance to treatment, as well as, his quality of life. Particulate formulations have been investigated as an alternative to improve opioid efficacy and safety. Objective Summarise the available studies concerning micro and nanoencapsulated opioid formulations discussing their biopharmaceutical characteristics, such as composition, size, in vitro release, pharmacokinetic and antinociceptive profile. Methods Papers available in 1995–2015 at Medline, Science Direct and Web of Science databases were collected and assessed. Searches were performed using varied combinations of the keywords of this work. Results Opioid-loaded particles showed prolonged drug release with maintenance of serum therapeutic concentrations and extended analgesia when compared with the free drugs. The side effects incidences were reduced or maintained the same. Conclusion Particulate formulations can significantly increase both potency and safety profiles of opioids.     

Rational design of large flat nitrogen-doped graphene oxide quantum dots with green-luminescence suitable for biomedical applications

Rational synthesis and simple methodology for the purification of large (35–45 nm in lateral size) and flat (1.0–1.5 nm of height) nitrogen-doped graphene oxide quantum dots (GOQDs) are presented. The methodology allows robust metal-free and acid-free preparation of N-GOQDs with a yield of about 100% and includes hydrothermal treatment of graphene oxide with hydrogen peroxide and ammonia. It was demonstrated that macroscopic impurities can be separated from N-GOQD suspension by their coagulation with 0.9% NaCl solution. Redispersible in water and saline solutions, particles of N-GOQDs were characterized using tip-enhanced Raman spectroscopy (TERS), photoluminescent, XPS, and UV-VIS spectroscopies. The size and morphology of N-GOQDs were studied by dynamic light scattering, AFM, SEM, and TEM. The procedure proposed allows nitrogen-doped GOQDs to be obtained, having 60–51% of carbon, 34–45% of oxygen, and up to 7.2% of nitrogen. The N-GOQD particles obtained in two hours of synthesis contain only pyrrolic defects of the graphene core. The fraction of pyridine moieties grows with the time of synthesis, while the fraction of quaternary nitrogen declines. Application of TERS allows demonstration that the N-GOQDs consist of a graphene core with an average crystallite size of 9 nm and an average distance between nearest defects smaller than 3 nm. The cytotoxicity tests reveal high viability of the monkey epithelial kidney cells Vero in the presence of N-GOQDs in a concentration below 60 mg L⁻¹. The N-GOQDs demonstrate green luminescence with an emission maximum at 505 nm and sedimentation stability in the cell culture medium.

This paper reveals the methodology for robust preparation of purified nitrogen-doped graphene oxide quantum dots with non-cytotoxic activity against monkey epithelial kidney cells (Vero ATCC® CCL-81™).