Visceral Leishmaniasis and Natural Infection Rates of Leishmania in Lutzomyia longipalpis in Latin America

Leishmaniasis, a neglected disease caused by protozoans of the Leishmania genus, is still present in 98 countries with about two million new cases yearly worldwide. It is transmitted by female phlebotomine sandflies and presents itself as cutaneous, mucocutaneous and visceral clinical forms, depending on the Leishmania species and the parasite‐host relationship. Visceral leishmaniasis (VL) is caused by Leishmania (Leishmania) infantum chagasi, endemic in 12 countries of Latin America, with 90% of the cases reported in Brazil. VL is characterized by irregular bouts of fever, weight loss, hepatosplenomegaly and pancytopenia, being highly fatal with no treatment. The main strategy in limiting the expansion of VL, besides the treatment of human cases, is the control of the vector Lutzomyia longipalpis and its reservoirs. There are only few studies on the natural infection of Leishmania species, especially in relation to its endemic distribution. Epidemiological studies of leishmaniasis may indicate the infection rate of parasites in sandflies in order to assess the populations at risk and to direct public health control strategies. In this context, we aimed to review the main features of VL with regard the distribution of disease cases and natural infection rates of Leishmania in Lu. longipalpis in Latin America

Ammonia Airship Cooling: An Option for Renewable Cooling in the Tropics

The world is warming, and the demand for cooling is increasing. Developing a future green hydrogen economy will also increase the demand for cooling for hydrogen liquefaction. This increase in cooling demand will happen mainly in tropical and developing countries due to their increase in population, improvements in quality of life, and the export of their renewable potential with liquid hydrogen. To solve this increase in demand for cooling, this paper proposes the use of ammonia airship cooling (AAC). AAC extracts cold from the tropopause (−80 °C) with airships and ammonia refrigeration cycles. The liquid ammonia is then transported back to the surface to provide low temperature cooling services (−33 °C). This cooling service is particularly interesting for lowering the electricity consumption in hydrogen liquefaction plants. If all the technological challenges mentioned in the paper are addressed, it is estimated that the cost of cooling with the technology is 8.25 USD/MWht and that AAC could reduce the electricity demand for hydrogen liquefaction by 30%. AAC is an innovative renewable cooling technology that has the potential to complement other renewable energy sources in a sustainable future

Evaluation of acute oral toxicity and diuretic activity of Rudgea viburnoides (Cham.) Benth. (congonha-de-bugre)

Rudgea viburnoides é utilizada popularmente como diurética, hipotensora, antirreumática, antissifilítica, depurativa do sangue e tratamento da dispepsia. Este trabalho teve como objetivos avaliar a toxicidade aguda e a atividade diurética do extrato etanólico bruto (EEBFRV) das folhas da R. viburnoides. Na toxicidade aguda empregou-se o teste de Classe, nas doses de 2000 e 5000 mg/kg, dose única, gavage, em camundongos Swiss e ratos Wistar (ambos os sexos). Na atividade diurética administrou-se em ratas Wistar o extrato bruto (40, 80 e 160 mg/kg, furosemida 20 mg/kg (controle +) e solução salina 0,9% (controle -). Não houve letalidade ou sinais de intoxicação, indicando baixa toxicidade desse extrato. O efeito diurético foi dose-dependente nas 24 h, com aumento dos parâmetros: volume de urina 24 h, excreção dos eletrólitos sódio, potássio e cloreto, uréia e creatinina. Os resultados até o momento, podem justificar a sua utilização popular como diurética.Rudgea viburnoides is popularly used as anti-hypertensive, anti-rheumatic, antissifilitic, blood depurative and for treatment of dyspepsia (leaves, bark, tea). The acute toxicity of ethanolic extract (EEBFRV) in single dose was performed by gavage of doses of 2000 and 5000 mg/kg in Swiss mice and Wistar rats, both sexes, by the class test. To diuretic activity in Wistar rats, it was used the EEBFRV at the doses of 40, 80 and 160 mg/kg, furosemide 20 mg/kg (control +), and saline solution 0.9 % (control -). Regarding acute toxicity, no mortality and no toxicity signs at the dose levels were observed, indicating low toxicity of the extract. The EEBFRV showed statistically significant dose-dependent diuretic effect in 24 h, increasing all parameters evaluated (24h urine volume, excretion of Na+, K+ and Cl- electrolytes, urea (BUN) and creatinine). Thus, the results so far may justify the popular use of Rudgea viburnoides as diuretic.Colegio de Farmacéuticos de la Provincia de Buenos Aire

Twenty-six years of HIV science: an overview of anti-HIV drugs metabolism

From the identification of HIV as the agent causing AIDS, to the development of effective antiretroviral drugs, the scientific achievements in HIV research over the past twenty-six years have been formidable. Currently, there are twenty-five anti-HIV compounds which have been formally approved for clinical use in the treatment of AIDS. These compounds fall into six categories: nucleoside reverse transcriptase inhibitors (NRTIs), nucleotide reverse transcriptase inhibitors (NtRTIs), non-nucleoside reverse transcriptase inhibitors (NNRTIs), protease inhibitors (PIs), cell entry inhibitors or fusion inhibitors (FIs), co-receptor inhibitors (CRIs), and integrase inhibitors (INIs). Metabolism by the host organism is one of the most important determinants of the pharmacokinetic profile of a drug. Formation of active or toxic metabolites will also have an impact on the pharmacological and toxicological outcomes. Therefore, it is widely recognized that metabolism studies of a new chemical entity need to be addressed early in the drug discovery process. This paper describes an overview of the metabolism of currently available anti-HIV drugs.Da identificação do HIV como o agente causador da AIDS, ao desenvolvimento de fármacos antirretrovirais eficazes, os avanços científicos na pesquisa sobre o HIV nos últimos vinte e seis anos foram marcantes. Atualmente, existem vinte e cinco fármacos anti-HIV formalmente aprovados pelo FDA para utilização clínica no tratamento da AIDS. Estes compostos são divididos em seis classes: inibidores nucleosídeos de transcriptase reversa (INTR), inibidores nucleotídeos de transcriptase reversa (INtTR), inibidores não-nucleosídeos de transcriptase reversa (INNTR), inibidores de protease (IP), inibidores da entrada celular ou inibidores de fusão (IF), inibidores de co-receptores (ICR) e inibidores de integrase (INI). O metabolismo consiste em um dos maiores determinantes do perfil farmacocinético de um fármaco. A formação de metabólitos ativos ou tóxicos terá impacto nas respostas farmacológicas ou toxicológicas do fármaco. Portanto, é amplamente reconhecido que estudos do metabolismo de uma nova entidade química devem ser realizados durante as fases iniciais do processo de desenvolvimento de fármacos. Este artigo descreve uma abordagem do metabolismo dos fármacos anti-HIV atualmente disponíveis na terapêutica

The geochemistry of modern calcareous barnacle shells and applications for palaeoenvironmental studies

Thoracican barnacles of the Superorder Thoracicalcarea Gale, 2016 are sessile calcifiers which are ubiquitous in the intertidal zone and present from very shallow to the deepest marine environments; they also live as epiplankton on animals and detritus. The geochemical composition of their shell calcite has been shown to yield information about environmental conditions, but comprehensive analyses of barnacle shell geochemistry are so far lacking. Here, a dataset is reported for Mg/Ca, Sr/Ca, Mn/Ca, Fe/Ca, as well as carbon and oxygen isotope ratios for 42 species from the Balaniformes, Verruciformes, Scalpelliformes and Lepadiformes. Barnacles predominantly form low-Mg-calcite with very high Sr/Ca ratios averaging 4.2 mmol/mol. The Mn/Ca and Fe/Ca ratios in shell plates are variable and can exceed > 4mmol/mol in barnacles that are attached to manmade structures or live close to (anthropogenic) sources of Mn and Fe. No strong phylogenetic control on the average element/Ca ratios is observed in barnacles. The Balaniformes show a ca. 40 % enrichment of Mg in their scuta and terga as compared to other shell plates — a pattern which is not seen in other barnacles. The combination of low to medium Mg/Ca ratios and high Sr/Ca ratios is rare for marine biogenic calcite and Barnacles may thus become important for robustly reconstructing past seawater composition, if this signature is also present in fossil barnacle calcite and can be used alongside other fossil taxa with different Sr incorporation behaviour. Carbon and oxygen isotope data support the view that the oxygen isotope thermometer for barnacles is robust and that most barnacle species form their calcite in, or near, isotopic equilibrium with ambient water. The Lepadiformes, however, show a tendency for strong co-variation of δ13C with δ18O values and depletion in 13C and 18O which is attributed to isotopic disequilibrium during shell secretion. Strong systematic fluctuations in Mg/Ca ratios over length scales of ca. 5 to 15 µm are exhibited by the scalpelliform species Capitulum mitella, the only studied species which consistently forms high-Mg-calcite, and are tentatively linked to tidal control on the shell secretion pattern. Cathodoluminescence images for this species suggest that additionally a seasonal pattern of Mn distribution in its shell plates is recorded, pointing to a potential use for reconstruction of seasonal changes in terrestrial element supply