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In this study, the antifungal potential of chemical constituents from Piper pesaresanum and some synthesized derivatives was determined against three phytopathogenic fungi associated with the cocoa crop. The methodology included the phytochemical study on the aerial part of P. pesaresanum, the synthesis of some derivatives and the evaluation of the antifungal activity against the fungi Moniliophthora roreri, Fusarium solani and Phytophthora sp. The chemical study allowed the isolation of three benzoic acid derivatives (1-3), one dihydrochalcone (4) and a mixture of sterols (5-7). Seven derivatives (8-14) were synthesized from the main constituents, of which compounds 9, 10, 12 and 14 are reported for the first time. Benzoic acid derivatives showed strong antifungal activity against M. roreri, of which 11 (3.0 ± 0.8 µM) was the most active compound with an IC50 lower compared with positive control Mancozeb® (4.9 ± 0.4 µM). Dihydrochalcones and acid derivatives were active against F. solani and Phytophthora sp., of which 3 (32.5 ± 3.3 µM) and 4 (26.7 ± 5.3 µM) were the most active compounds, respectively. The preliminary structure-activity relationship allowed us to establish that prenylated chains and the carboxyl group are important in the antifungal activity of benzoic acid derivatives. Likewise, a positive influence of the carbonyl group on the antifungal activity for dihydrochalcones was deduced.

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Leishmaniasis is a parasite disease transmitted by the bites of sandflies. Cutaneous leishmaniasis is the most common form of the disease and it is endemic in the Americas. Around 70 animal species, including humans, have been found as natural reservoir hosts of leishmania parasites. Among the reservoirs, dogs are the most important ones due to their proximity to the human habitat. Infection by leishmaniasis does not invariably cause illness in the host, and it also can remain asymptomatic for a long period, specially in dogs. In this work we formulate a model to study the transmission of the disease among the vector, humans and dogs. Our main objective is to asses the impact of dogs as a reservoir as well as the impact of asymptomatic humans and dogs on the spread of leishmaniasis. For this end we calculate the Basic Reproduction Number of the disease and we carry out sensitivity analysis of this parameter with respect to the epidemiological and demographic parameters.

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Vector-borne diseases are one of the major public health problems in the world with the fastest spreading rate. Control measures have been focused on vector control, with poor results in most cases. Vaccines should help to reduce the diseases incidence, but vaccination strategies should also be defined. In this work, we propose a vector-transmitted SIR disease model with age-structured population subject to a vaccination program. We find an expression for the age-dependent basic reproductive number R(0), and we show that the disease-free equilibrium is locally stable for R(0) ≤ 1, and a unique endemic equilibrium exists for R(0) > 1. We apply the theoretical results to public data to evaluate vaccination strategies, immunization levels, and optimal age of vaccination for dengue disease.

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In this paper, we analyse the interaction of different species of birds and mosquitoes on the dynamics of West Nile virus (WNV) infection. We study the different transmission efficiencies of the vectors and birds and the impact on the possible outbreaks. We show that the basic reproductive number is the weighted mean of the basic reproductive number of each species, weighted by the relative abundance of its population in the location. These results suggest a possible explanation of why there are no outbreaks of WNV in Mexico.

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Objetivo: Valorar la satisfacción de los pacientes con el servicio de dispensación durante la realización del pilotaje del protocolo de dispensación en farmacia comunitaria. Material y métodos: Estudio observacional descriptivo transversal. Se midió la satisfacción con un cuestionario validado en farmacias comunitarias de las Provincias de Murcia y Málaga, España. El cuestionario auto administrado y anónimo midió dos áreas de satisfacción global del paciente: Referente al trato personal recibido y referente al servicio recibido. Resultados: De 60 farmacias participantes, se obtuvieron 335 cuestionarios, siendo válidos 329. El 71,2% de los pacientes se mostraron "muy satisfechos" respecto al trato del personal y respecto al servicio realizado se obtuvo un 59,1% "muy satisfecho". Discusión: El estudio refleja una gran aceptación y satisfacción de los pacientes con el servicio recibido, sin embargo, la mayoría de participantes son usuarios habituales de la farmacia, lo que puede sobreestimar los resultados obtenidos. Resultaría interesante valorar los cambios de satisfacción con el tiempo, siendo recomendable buscar nuevos enfoques que determinen las expectativas y preferencias de los pacientes, mostrando posibles causas de insatisfacción. Conclusión: La satisfacción de los pacientes con el trato personal y el servicio de dispensación recibido resultó muy elevada(AU)

Aim: To assess patient satisfaction with the service of dispensing during the pilot implementation of the protocol in community pharmacy dispensing. Methods: Made in community pharmacies of Murcia and Malaga provinces in Spain. Satisfaction was measured with a validated 10-item questionnaire, structured, multidimensional, with Likert scale of five continuous categories. The validated questionnaire measures two areas of overall patient satisfaction: 1. Concerning the personal treatment received. 2 .- Regarding the service received. Results: Of 60 participating community pharmacies, we obtained 335 questionnaires, from which 329 were valid. The results obtained were 71.2% very satisfied about the treatment of staff and a 59.1% very satisfied with the dispensation service. Discussion: The study shows a wide acceptance of patient satisfaction with the service, although mostly are frequent patients of participating pharmacies, which may overestimate the results. It would be interesting to evaluate changes in satisfaction over time and it is recommended to explore new approaches to determine the expectations and preferences of patients, showing possible causes of dissatisfaction. Further studies should be conducted in the future. Conclusions: The satisfaction of personal treatment received and the dispensing service was very high(AU)

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Chagas disease, also known as American trypanosomiasis, is a potentially life-threatening illness caused by the protozoan parasite, Trypanosoma cruzi. The main mode of transmission of this disease in endemic areas is through an insect vector called triatomine bug. Triatomines become infected with T. cruzi by feeding blood of an infected person or animal. Chagas disease is considered the most important vector borne infection in Latin America. It is estimated that between 16 and 18 millions of persons are infected with T. cruzi, and at least 20,000 deaths each year. In this work we formulate a model for the transmission of this infection among humans, vectors and domestic mammals. Our main objective is to assess the effectiveness of Chagas disease control measures. For this, we do sensitivity analysis of the basic reproductive number R0 and the endemic proportions with respect to epidemiological and demographic parameters.

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In this paper we analyze the impact of seasonal variations on the dynamics of West Nile Virus infection. We are interested in the generation of new epidemic peaks starting from an endemic state. In many cases, the oscillations generated by seasonality in the dynamics of the infection are too small to be observable. The interplay of this seasonality with the epidemic oscillations can generate new outbreaks starting from the endemic state through a mechanism of parametric resonance. Using experimental data we present specific cases where this phenomenon is numerically observed.

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Puerto Rico has implemented Health Care Reform legislation that shifted medically indigent and underserved persons from direct care by public sector institutions to managed care arrangements through the private sector. Our aim is to assess how previously underserved women with breast cancer have fared during the first three years of the Reform. Medical claims data were obtained on breast cancer cases in San Juan who were either enrolled in the capitated Reform plan or in a commercial policy offered by the same insurer. A set of indicators reflecting initial therapy, use of key services, and cumulative utilization rates of various medical procedures were constructed. Statistical tests were conducted to assess whether these indicators differed between Reform- and commercially-insured patients. Failure to reject null hypotheses of indicator differences were then used to judge Reform progress. We found some differences, but they were neither pervasive nor unidirectional. On balance, we conclude that previously underserved women are being treated for breast cancer roughly on par with other patients. This conclusion, however, is preliminary and subject to important qualifications.

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In this work we formulate and analyze a mathematical model for the transmission of West Nile Virus (WNV) infection between vector (mosquito) and avian population. We find the Basic Reproductive Number R0 in terms of measurable epidemiological and demographic parameters. R0 is the threshold condition that determines the dynamics of WNV infection: if R0< or =1 the disease fades out, and for R0 >1 the disease remains endemic. Using experimental and field data we estimate R0 for several species of birds. Numerical simulations of the temporal course of the infected bird proportion show damped oscillations approaching the endemic value.

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We formulate a non-linear system of differential equations that models the dynamics of dengue fever. This disease is produced by any of the four serotypes of dengue arbovirus. Each serotype produces permanent immunity to it, but only a certain degree of cross-immunity to heterologous serotypes. In our model we consider the relation between two serotypes. Our interest is to analyze the factors that allow the invasion and persistence of different serotypes in the human population. Analysis of the model reveals the existence of four equilibrium points, which belong to the region of biological interest. One of the equilibrium points corresponds to the disease-free state, the other three equilibria correspond to the two states where just one serotype is present, and the state where both serotypes coexist, respectively. We discuss conditions for the asymptotic stability of equilibria, supported by analytical and numerical methods. We find that coexistence of both serotypes is possible for a large range of parameters.

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