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Aug 2018
F. Favaro PatriciaCorresponding author
Department of Veterinary Medicine and Animal Health, School of Veterinary Medicine and Animal Science (FMVZ), University of São Paulo (USP), São Paulo - SP, Brazil
This brief report summarizes equine influenza activity in South America, noting clinical presentation, transmission dynamics, and recent outbreaks. It reviews vaccination strategies, biosecurity measures, and surveillance needs for controlling spread. Practical guidance is provided for veterinarians and stable managers to reduce risk during regional circulation.
Aug 2017 DOI 10.14302/issn.2575-1212.jvhc-17-1661
Parreño VivianaCorresponding author
National Council of Scientific and Technical Research - CONICET, Buenos Aires, Argentina.
Serum samples from wild and domestic South American Camelids (SAC) from Argentina, collected before (2008), during (2009) and after (2010) the 2009 H1N1 influenza pandemic were tested by hemagglutination-inhibition assay (HIA) to evaluate the seroprevalence of antibodies (Ab) against different subtypes of influenza A viruses: A(H1N1)pdm09, A/sw/Argentina/SIV/2009(H3N2) and A/eq/Argentina/97(H3N8). For A(H1N1), an ELISA using a recombinant H1-hemmaglutinin from a reference strain (HA0 PuertoRico/8/1934) was also conducted. Serum samples from Guanacos (126), vicugnas (21) and llamas (100) from Jujuy, Mendoza and Río Negro provinces were analyzed; no clinical signs of respiratory disease were detected, reason for which no nasal swabs were obtained. No seropositive reactors to H3N2 nor H3N8 variants were detected, nevertheless high incidence of Ab reactive to A(H1N1)pdm09 were found by HIA; results which were confirmed by ELISA. The Ab seropositive animals to H1-like IAV found in llamas from Jujuy, and Mendoza (2009) were 78% and 86% by HIA and ELISA, respectively. Thirty-seven samples taken over the three years from guanacos kept in captivity in Rio Negro showed 62% of seropositive animals, while wild guanacos from Mendoza sampled in 2010 showed 36% seropositive animals to H1-like IAV, by both techniques. Finally, wild vicugnas from Jujuy, sampled in 2008 showed 38% and 52% seropositive animals to H1-like IAV by HIA and ELISA, respectively. Our results could indicate the potential role of these species as a reservoir of this zoonotic viral agent of high impact in Public Health, and may suggest that SAC populations might have been infected with an influenza strain antigenically related to H1 IAV. . Surprisingly, for llama and guanaco populations sampled over time in Jujuy and Río Negro, respectively, the HIA and ELISA geometric mean Ab titers (GMT) for 2008 were significantly higher than the ones of 2010. In addition, HIA and ELISA Ab titers found in domestic llamas were significantly higher than those detected in wild vicugnas sampled during that year (2008) in Jujuy. New field campaigns are in progress to collect serum samples and nasal swabs in order to isolate and characterize the virus responsible for triggering H1 reactive Abs. These findings remark the need to better understand the dynamics and ecology of influenza A virus within Sacs populations.
Jul 2024 DOI 10.14302/issn.3070-3379.jwc-24-5072
Gobato RicardoCorresponding author
Extratropical cyclones are common in the South Atlantic. They generally arise with the passage of cold fronts to the south of the South American continent, crossing the south of Chile and Argentina, in the regions of Puerto Natales, Punta Arenas (Chile), Rio Galegos, Rio Grande, El Calafate and Ushuaia (Argentina). The extratropical cyclone analyzed presented at its peak the very characteristic shape of a Chinese dragon. Other cyclones in the form of a Cote's spiral curve are part of this analysis (Gobato et al., 2018-2023). They present a mathematical form of a double Cotes Spiral curve. Here called the Dragonhead cyclone, indicate a structural similarity with spiral galaxies, especially NGC 5247, in the constellation Virgo. With an area of influence and a size of around 3,247 thousand km2 at its peak, it moved quickly in a west-northwest (WNW) direction, with an average speed of 76 km/h, with winds of 84 km/h at 100 km from the nucleus, as it passed north of the Falkland Islands (Malvinas Islands). The cyclone temperature during its trajectory varies from -45ºC to -50ºC at its edge, while at its core it varies between -10ºC to -25ºC. In the data collected (Gobato et al., 2018-2023), and analyzed from the Dragonhead cyclone, it is clear that all extratropical cyclones that appear south of the South American continent, below 40° latitude, have the shape of a spiral curve, like the spiral galaxy. Most of these are in the form of a double Cote’s spiral curve.
Sep 2022 DOI 10.14302/issn.3070-3379.jwc-22-4202
Gobato RicardoCorresponding author
Green Land Landscaping and Gardening, Seedling Growth Laboratory, 86130-000, Parana, Brazil.
A subtropical cyclone is a weather system that has some characteristics of a tropical cyclone and some characteristics of an extratropical cyclone. They can form between the equator and the 50th parallel. In mathematics, a spiral is a curve which emanates from a point, moving farther away as it revolves around the point. The characteristic shape of hurricanes, cyclones, typhoons is a spiral. There are several types of turns, and determining the characteristic equation of which spiral the Extratropical Cyclone (EC) fits into is the goal of the work. The study demonstrates a double spiral for the extratropical cyclone, similarly Lindblad (1964) demonstrates a double spiral, to demonstrate the structure of spiral galaxies. Despite the data obtained in the EC that passed through the southern tip of South America west and east of the Falklands Islands, everything indicates that the short occurrence ECs indicate the double spiral structure, but with the structure of a Cote’s double spiral.
Sep 2020 DOI 10.14302/issn.2372-6601.jhor-20-3544
Manuel Vargas-Hernández VíctorCorresponding author
Gynecology Service, Hospital Juárez de México; Mexican Academy of Surgery
In Mexico, breast cancer is the second most common site of cancer in women and in most developed and emerging countries. Incidence rates have increased in many countries, although in some, mortality has remained stable with a slight reduction. There are geographical differences with high rates of breast cancer in North America, Northern Europe and Oceania, and lower rates in Central and South America, South and East Europe; in addition to emerging countries in Africa and Asia. Genetic and hereditary factors constitute less than 5% of breast cancer cases and other risk factors for breast cancer are related to the reproductive life of the woman. This work was carried out in order to determine if the risk factors considered classic are really associated with breast cancer in our sample of Mexican women studied.
Jul 2020 DOI 10.14302/issn.2471-2140.jaa-20-3478
R.A. Mans DennisCorresponding author
Department of Pharmacology, Faculty of Medical Sciences, Anton de Kom University of Suriname, Paramaribo, Suriname
Plant-based preparations are commonly used in Suriname (South America) as adaptogens. In this study, fifteen alleged adaptogenic Surinamese plants have been assessed for their antioxidant activity (AA), total phenolic contents (TPC), and total flavonoid contents (TFC). The investigated plants were Anacardium occidentale, Spondiasdulcis, Annona muricata, Euterpe oleracea, Oenocarpus bacaba, Luffa acutangula, Punicagranatum, Malpighia emarginata, Syzygiumaqueum, Syzygiumcumini, Averrhoa carambola, and Renealmiaalpinia (fruit); Hibiscus sabdariffa (calyx); as well as Aloe vera and Cestrum latifolium (leaf). Aqueous extracts (1 - 3,000 μg/ mL) were prepared. AA was determined by the FRAP and the DPPH assay. TPC and TFC were determined by the Folin-Ciocalteu’s and an AlCl3 colorimetric method, respectively, using gallic acid (GA) and rutin (R), respectively, as standards. Data are means ± SDs (n ≥ 3; P < 0.05). FRAP values and DPPH-scavenging activities correlated positively with each other and with TPC but not with TFC. The preparations from M. emarginata, A. carambola, A. occidentale, O. bacaba, C. latifolium, and H. sabdariffa displayed the highest FRAP values (54 ± 14 to 412 ± 30 µM Fe2+/100 μg), DPPH-scavenging activities (IC50 values of 33 ± 14 to 250 ± 50 μg/mL), and TPC (51 ± 4 to 280 ± 78 µM GAE/100 µg). TFC of all samples were ≤ 10 ± 3 RE/100 µg. The adaptogenic properties of these plants may (partially) be attributed to their high content of antioxidant phenolic compounds and may make them candidates of novel sources of health-promoting antioxidants.