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ABSTRACTThe in vitroeffects of 18 dinuclear thiolato-bridged arene ruthenium complexes (1 monohiolato compound, 4 dithiolato compounds, and 13 trithiolato compounds), originally designed as anticancer agents, on the apicomplexan parasite Toxoplasma gondiigrown in human foreskin fibroblast (HFF) host cells were studied. Some trithiolato compounds exhibited antiparasitic efficacy at concentrations of 250 nM and below. Among those, complex 1 and complex 2 inhibited T. gondiiproliferation with 50% inhibitory concentrations (IC50s) of 34 and 62 nM, respectively, and they did not affect HFFs at dosages of 200 μM or above, resulting in selectivity indices of >23,000. The IC50s of complex 9 were 1.2 nM for T. gondiiand above 5 μM for HFFs. Transmission electron microscopy detected ultrastructural alterations in the matrix of the parasite mitochondria at the early stages of treatment, followed by a more pronounced destruction of tachyzoites. However, none of the three compounds applied at 250 nM for 15 days was parasiticidal. By affinity chromatography using complex 9 coupled to epoxy-activated Sepharose followed by mass spectrometry, T. gondiitranslation elongation factor 1α and two ribosomal proteins, RPS18 and RPL27, were identified to be potential binding proteins. In conclusion, organometallic ruthenium complexes exhibit promising activities against Toxoplasma, and the potential mechanisms of action of these compounds as well as their prospective applications for the treatment of toxoplasmosis are discussed.

Background. Few data have been published regarding long-term mortality in patients with Parkinson’s disease treated with DBS. Methods. This study analyzed long-term mortality rates, causes, and correlates in PD patients treated with DBS. Results. 184 consecutive patients were included; mean follow-up was 50 months. Fifteen deaths occurred (total 8.15%, annual mortality rate 1.94%). Mean age at disease onset and at surgery was 48±2.4 and 63±1.6 years, respectively. Mean disease duration until death was 21±7.8 years. Most deaths related to stroke, myocardial infarction, other vascular/heart disorders, or severe infection; one suicide was recorded. Deceased PD patients were mostly male and had lower motor benefit after DBS, but univariate analysis failed to show significant differences regarding gender and motor benefit. Survival was 99% and 94% at 3 and 5 years. Conclusions. Long-term survival is to be expected in PD patients treated with DBS, possibly higher than previously expected. Death usually supervenes due to vascular events or infection.

The bone marrow (BM) niche is known to exert a protective effect on lymphoid tumors, such as multiple myeloma (MM), where mesenchymal stem cell interactions with clonal plasma cells increase tumor proliferation and survival. However, certain cells within the BM milieu, such as mature osteoblasts and osteocytes, have demonstrated the potential to inhibit tumor growth; utilizing these cells presents a promising new anti-cancer approach. Hence, designing better methods of bone-specific delivery for both direct cancer cell treatment and indirect treatment through the modulation of bone cells may result in a potent, two-pronged anti-cancer strategy. Our work aimed to develop a novel system to target both MM and bone cells to induce greater osteogenesis and hamper tumor growth.PEG–PLGA nanoparticles (NPs) coupled to alendronate (“bone-targeted”) or alone (“non-targeted”) were formulated and loaded with bortezomib (“BTZ-NPs”) or left empty (“BTZ-free”). NPs were characterized for their physiochemical properties, including size (using dynamic light scattering; surface charges (Zeta potential); and bone affinity (using hydroxyapatite binding). NPs were engineered with different formulation methods and those with the optimal physiochemical characteristics and drug encapsulation efficiency were used for further studies. BTZ release kinetics were analyzed using HPLC. Anti-MM effects were assessed in vitro using MTT, bioluminescence (BLI) and Annexin V/PI apoptosis flow cytometry analysis on MM1S cells. In vivo, efficacy was measured by mouse weight, BLI and survival after i.v. cancer cell injections in mice. Cellular uptake was assessed in vitro by flow cytometry and in vivo biodistribution was assessed using fluorescent whole body and fixed section imaging. Bone specificity was assessed in vitro by co-culture of bone-targeted and non-targeted NPs with bone chips or hydroxyapatite using fluorescence and TEM imaging.In an in vivo model of myeloma treatment, female Nod/SCID beige mice were injected i.v. with 4 × 106 Luc+/GFP+ MM1S cells and, at day 21, treated with a) BTZ, b) BTZ-bone-targeted NPs, c) BTZ-non-targeted NPs or d) BTZ-free bone-targeted NPs. Using an in vivo model of pre-treatment for cancer prevention, mice were pre-treated with i.p. injections of BTZ-bone-targeted NPs and appropriate controls thrice weekly for 3 weeks. They were then injected i.v. with Luc+/GFP+ 5TGM1 or MM1S cells and monitored for BLI and survival. Static and dynamic bone histomorphometry and μCT were used to assess effects of pre-treatment on bone formation and osteolysis prevention.Our biodegradable, NPs had uniform size distribution within the range of 100 to 200 nm based on the type of formulation, with a zeta potential of ±5mV. Bone- targeted NPs showed high affinity towards bone mineral in vitro and better skeletal accumulation in vivo compared to non-targeted NPs. NPs were easily up-taken by cells in vitro, and BTZ release kinetics showed a burst followed by a sustained-release pattern over 60 hrs. BTZ-NPs induced apoptosis in MM cells in vitro. Importantly, BTZ-bone-targeted-NP pre-treated mice showed significantly less tumor burden (BLI) and longer survival than free drug or drug-free bone-targeted NPs, thus demonstrating a tumor-inhibiting effect unique to the BTZ-bone-targeted-NPs. Pre-treatment with BTZ increased bone formation in tibias and femurs, as measured by μCT of bone volume/total volume, and trabecular thickness and number, suggesting that increased bone volume may inhibit MM. In a second mouse model, both BTZ-bone-targeted NPs and BTZ-free NPs were equally able to reduce tumor growth in vivo when given after tumor formation.Bone-targeted nanoparticles hold great potential for clinical applications in delivering chemotherapies to bone marrow niches, reducing off-target effects, increasing local drug concentrations, and lengthening the therapeutic window. BTZ-bone-targeted NPs are able to slow tumor growth and increase survival in mice when used as a pre-treatment. This may result, at least in part, from BTZ-induced increased bone formation. These findings indicate that BTZ-bone-targeted NPs exert a chemopreventive effect in MM in vivo, thus suggesting their potential use in the clinical setting.Basto: BIND Therapeutics: Patent licensed by BIND, Patent licensed by BIND Patents & Royalties. Farokhzad:BIND Therapeutics: Employment, Equity Ownership; Selecta Biosciences: Employment, Equity Ownership. Ghobrial:Onyx: Membership on an entity’s Board of Directors or advisory committees; BMS: Membership on an entity’s Board of Directors or advisory committees; BMS: Research Funding; Sanofi: Research Funding; Novartis: Membership on an entity’s Board of Directors or advisory committees.

A letter to the editor is presented about the role of the expansion of the Earth's crust in the frequency and severity of earthquakes.

Gliosarcomas are rare and poorly characterized malignant brain tumors that exhibit a biphasic tissue pattern with areas of gliomatous and sarcomatous differentiation. These tumors are histological variants of glioblastoma, displaying a similar genetic profile and dismal prognosis. Up-regulation of PDGFR subfamily of tyrosine kinase members, PDGFR-α and c-Kit, and their intracellular effectors RAS/RAF/MAPK has a crucial role in the cancer development. In addition, signal transduction mediated by activating mutations of c-Kit and PDGFR can be effectively blocked by specific tyrosine kinase inhibitors, such as Imatinib mesylate. The aim of this study was to characterize the molecular alterations of PDGFR signaling in gliosarcomas. Six cases were analyzed by immunohistochemistry for the expression of PDGFR-α, c-Kit and their ligands PDGF-A and SCF, respectively. The cases were further evaluated for the presence of activating mutations of PDGFR-α (exons 12 and 18) and c-kit (exons 9, 11, 13, and 17), as well as B-RAF (exons 11 and 15). Expression of PDGF-A was found in all cases and co-expression of PDGFR-α was observed in three cases. Four cases showed expression of SCF, and c-Kit was observed only in one case that also expressed SCF. Generally, immunoreaction predominates in the glial component. The mutational analysis of PDGFR-α showed the presence of an IVS17-50insT intronic insertion in two cases, one of them also with a 2472C > T silent mutation; this silent mutation was also found in another case. Glioma cell line analysis of IVS17-50insT insertion showed no influence on PDGFR-α gene splicing. No mutations were detected in c-kit and B-RAF oncogenes. Our Results indicate that activating mutations of PDGFR-α, c-kit and B-RAF are absent in gliosarcomas. Nevertheless, the presence of a PDGFR-a/PDGFA and c-Kit/SCF autocrine/paracrine stimulation loop in a proportion of cases, supports the potential role of specific tyrosine kinase inhibitors in the treatment of gliosarcomas.

Pretendemos avaliar a eficácia da VNI em doentes com SOH. Foram comparados os efeitos da VNI em dois grupos de doentes com insuficiência respiratória crónica hipercápnica: um grupo com SOH (n=13, média de idades=63 anos) e outro com cifoescoliose (n=23, média de idades=62,5 anos).

With the aim of finding a relation between the decrease in systolic blood pressure (SBP) with Diltiazem with the previous SBP values, we studied a group of 29 patients (14 men) with a mean age of 55.2±9.4 years by 24 hour ABPM. Individual hourly SBP values were evaluated in a randomised, crossover study after a period of 4 weeks with a daily dose of Diltiazem 180 mg in slow release capsules or after 4 weeks with placebo. We obtained 632 pairs of values with an average SPB after placebo = 143.8±21.6 mm Hg and after Diltiazem = 139.1±17.7 mm Hg (p<0.0001). We divided the SBP values in 4 groups and verified that there was a significant decrease when SBP was > 140 mm Hg, and that below this value there was not any decrease. (See Table below) PlaceboDiltiazemSBP fallSBP GroupNSBP (mmHg)SBP (mmHg)(mmHg)Significance*Mean±SDMean±SDMean±SD>160 mm Hg110178.3±16.4157.7±17.820.6±14.5p<0.0001>140 < 161 mm Hg218149.8±5.8142.2±12.87.7±12.8p<0.001>120 < 141 mm Hg231132.0±5.1132.9±12.9-0.7±13.0Not Significant<121 mm Hg73111.4±8.9121.5±16.0-10.0±15.6p<0.001Total632143.9±21.7139.1±17.74.8±16.3p<0.001* (paired samples t-test) We found with Diltiazem a close correlation between the SBP values and the SBP decrease with a correlation coefficient = 0.6 and a 2-tailed p < 0.0001 (Pearsons correlation). Diltiazem 180 mg in slow release capsules has a proportional effect on blood pressure evaluated by 24 hour ABPM: it produces a proportional decrease in the elevated blood pressure without inducing hypotension when patients present normal or low blood pressure values.

An antihypertensive drug taken once-a-day must cover the 24 hours with a trough:peak ratio greater than 50%. We evaluated the trough:peak ratio of slow release capsules of Diltiazem 180 mg taken in a single dose in the morning (8-10 a.m.) in 23 patients with essential hypertension with systolic or diastolic tensional load > 20%. Patients were submitted to a 24 hour Ambulatory Blood Pressure Monitoring (ABPM) after a double blind, crossover period of 4 weeks with Diltiazem 180 mg or placebo. Diltiazem 180 mg in slow release capsules significantly decreases Systolic Blood Pressure (SBP), Diastolic Blood Pressure (DBP) and Mean Blood Pressure (MBP) (24h mean, daytime - 08-23h - and night-time - 24-07h) (table). ABPM Results (Mean±SD)PlaceboDiltiazemSignificance24 h SBP (mm Hg)148.6 ± 7.0142.3 ± 6.4p<0.000124 h DBP (mm Hg)93.8 ± 8.187.9 ± 6.4p<0.000124 h MBP (mm Hg)121.2 ± 7.3115.1 ± 6.3p<0.0001Daytime SBP (mm Hg)152.6 ± 4.1145.2 ± 3.6p<0.0001Daytime DBP (mm Hg)98.5 ± 5.591.4 ± 4.2p<0.0001Daytime MBP (mm Hg)125.5 ± 4.3118.7 ± 3.9p<0.0001Night-time SBP (mm Hg)140.7 ± 4.2135.2 ± 4.0p=0.001Night-time DBP (mm Hg)84.6 ± 3.180.8 ± 3.3p=0.001Night-time MBP (mm Hg)112.7 ± 3.6108.0 ± 3.4p=0.001 The trough:peak ratio was calculated using the mean blood pressures at 8, 9 and 10 hours (trough) and at 18, 19, 20 hours (peak) for SBP, DBP and MBP. The comparison of the circadian curves of SBP between placebo and the therapeutic active period demonstrated that Diltiazem 180 mg in this formulation taken in the morning has a peak effect 10 to 13 hours after the dose and the anti-hypertensive effect is maintained for 22-24 hours. At night the curves get closer with no nocturnal hypotension. The calculated trough:peak ratios were high (90.4% for SBP, 89.4% for DBP and 81.0% for MBP). We concluded that Diltiazem 180mg in slow release capsules taken once daily in the morning efficaciously decreases blood pressure during 24 hours and respects the circadian blood pressure variation with a high trough:peak ratio and without nocturnal hypotension.

Verbal autopsies (VA) are frequently used to determine causas of death for individuals for whom there is no reliable clinical information regarding the terminal illness. VA interviews are used to note key symptoms and signs recalled by relatives of the deceased and diagnoses ascribed according to the symptom complexes. The VA technique assumes that individual disease entities have discrete symptom complexes and that these can be accurately recognized and recalled by the interewees. We have examined the accuracy with which specific symptoms are recalled over time by mothers or normal guardians of 491 children who died on the paediatric wards of two district hospitals in East Africa. Kwashiorkor, measles, trauma, generalized convulsions and neonatal tetanus were all reported with a high degree of accuracy for children who died of these conditions and had low false positive rates for children without these conditions. Recall was similar within 1 month of death compared to recall after 6 months for most symptoms and signs except neonatal tetanus where false positive reports by mothers increaaed with time since death. Symptoms and signs commonly used to describe malaria, respiratory tract and diarrhoea-related deaths were reported by mothers to have been present during the terminal illnes in 43% of cases where these features were absent. Recall abilities differed between the two communities studied for some symptoms and signs highlighting the importance of such studies in every setting where VA are applied.