One way to reduce dental fluorosis is by reducing the fluoride (F) concentration in dentifrice, but low-F dentifrice should be as effective as a standard dentifrice. This study evaluated in vitro whether the supplementation with sodium trimetaphosphate (TMP) of a dentifrice with low F content (500 μg/g) would provide a similar effect to that of a standard dentifrice. Bovine enamel blocks were submitted to a pH cycling regime incorporating daily exposures to a slurry of dentifrice: a low-F dentifrice with or without 0.1–3.0% TMP; an F-free, phosphate-free dentifrice (negative control), or a dentifrice with 1,100 μg/g F (positive control). The addition of TMP to dentifrice with or without F was associated with higher surface hardness and decreased loss of integrated subsurface hardness after pH cycling. The combination of 1% TMP and 500 μg F/g had a greater effect than the positive control dentifrice. It is concluded that the addition of TMP to the 500-μg F/g dentifrice allowed a similar or larger effect as compared with a standard dentifrice in this in vitro model.

Chagas disease is one of the most neglected tropical diseases in the world, affecting nearly 15 million people, primarily in Latin America. Only two drugs are used for the treatment of this disease, nifurtimox and benznidazole. These drugs have limited efficacy and frequently induce adverse effects, limiting their usefulness. Consequently, new drugs must be found. In this study, we demonstrated the in vitro trypanocidal effects of a series of four gallic acid derivatives characterized by a gallate group linked to a triphenylphosphonium (TPP+) moiety (a delocalized cation) via a hydrocarbon chain of 8, 10, 11, or 12 atoms (TPP+-C8, TPP+-C10, TPP+-C11, and TPP+-C12, respectively). We analyzed parasite viability in isolated parasites (by MTT reduction and flow cytometry) and infected mammalian cells using T. cruzi Y strain trypomastigotes. Among the four derivatives, TPP+-C10 and TPP+-C12 were the most potent in both models, with EC50 values (in isolated parasites) of 1.0 ± 0.6 and 1.0 ± 0.7 μM, respectively, and were significantly more potent than nifurtimox (EC50 = 4.1 ± 0.6 μM). At 1 μM, TPP+-C10 and TPP+-C12 induced markers of cell death, such as phosphatidylserine exposure and propidium iodide permeabilization. In addition, at 1 μM, TPP+-C10 and TPP+-C12 significantly decreased the number of intracellular amastigotes (TPP+-C10: 24.3%, TPP+-C12: 19.0% of control measurements, as measured by DAPI staining) and the parasite’s DNA load (C10: 10%, C12: 13% of control measurements, as measured by qPCR). Based on the previous mode of action described for these compounds in cancer cells, we explored their mitochondrial effects in isolated trypomastigotes. TPP+-C10 and TPP+-C12 were the most potent compounds, significantly altering mitochondrial membrane potential at 1 μM (measured by JC-1 fluorescence) and inducing mitochondrial transition pore opening at 5 μM. Taken together, these results indicate that the TPP+-C10 and TPP+-C12 derivatives of gallic acid are promising trypanocidal agents with mitochondrial activity.

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cARlos deRosAs 8 , susAnA elguetA 9 comité asesor para alistamiento y priorización para trasplante hepático en chile Analysis of the organ allocation system for liver transplantation in Chile Background: In Chile, organ allocation for liver transplantation (LT) in adults is prioritized according to the MELD-Na score. Exceptions such as Hepatocellular Carcinoma (HCC) and other non-HCC exceptions receive a score called Operational MELD score. Aim: To evaluate the effectiveness of the MELD-Na score and the operational MELD score as a prioritization system for LT in Chile. Material and Methods: Retrospective analysis of the waiting list (WL) of adult candidates (≥ 15 years) for elective LT in Chile from 2011 to 2017. The probability of leaving the WL, defined by death or contraindication for LT was compared in three groups: 1) Cirrhotic patients prioritized according to their real MELD-Na score (CPM), 2) HCC and 3) other non-HCC exceptions. Results: We analyzed 730 candidates for LT, with a median age of 57 years, 431 (56%) were men. In the study period, 352 LT were performed (48%). The annual exit rate was significantly higher in the CPM group (45.5%) compared to HCC (33.1%) and non-HCC (29.3%), (p < 0.001). Post LT survival was 86% at 1 year and 85% at 5 years, without significant differences between groups. In the CPM group, post-transplant survival was significantly lower (p < 0.05) in patients with MELD-Na ≥ 30 at transplant (81% per year) compared to patients with patients with MELD-Na < 30 (91% per year). Conclusions: MELD-Na score can discriminate very well patients who have a higher risk of death in the short and medium term. However, the assignment of operational scores for situations of exception produces inequities in the allocation of organs for LT and must therefore be carefully adjusted.

Una de las grandes controversias dentro del manejo médico integral del carcinoma hepatocelular es la estimación precisa de la efectividad de la terapia con quimioembolización transarterial. Las evidencias demuestran que la misma hace parte del núcleo de tratamiento para aquellos pacientes con tumores no resecables y, comparado con la resección hepática y ablación por radiofrecuencia, oferta supervivencia a largo plazo si cumplen las características de nódulo hasta 3 cm o menores sin invasión vascular. Presentamos un caso clínico de carcinoma hepatocelular atípico con manejo médico integral, mediante la quimioembolización transarterial, evidenciando por imágenes y macroscópicamente la efectividad de la misma hasta el trasplante hepático ortotópico.

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