Somatic embryogenesis in Simarouba glauca

Frequency of somatic embryogenesis from callus cultures derived from immature cotyledon explants of Simarouba glauca Linn. was highest on solid MS medium supplemented with 11.1 M benzyladenine and 13.42 M -naphthaleneacetic acid. On transfer of the somatic embryos into maturation medium containing half-strength MS medium supplemented with 1.89 M abscisic acid (ABA) and 2% (w/v)sucrose, 20–25 % of embryos germinated within 20 days of culture with distinct cotyledon, hypocotyl and radicle.     

Diarrhea outbreak during U.S. military training in El Salvador

Infectious diarrhea remains a major risk to deployed military units worldwide in addition to their impact on travelers and populations living in the developing world. This report describes an outbreak of diarrheal illness in the U.S. military’s 130^th Maneuver Enhancement Brigade deployed in San Vicente, El Salvador during a training and humanitarian assistance mission. An outbreak investigation team from U.S. Naval Medical Research Unit – Six conducted an epidemiologic survey and environmental assessment, patient interviews, and collected stool samples for analysis in an at risk population of 287 personnel from May 31^st to June 3^rd, 2011. Personnel (n = 241) completed an epidemiological survey (87% response rate) and 67 (27%) reported diarrhea and/or vomiting during the past two weeks. The median duration of illness was reported to be 3 days (IQR 2–4 days) and abdominal pain was reported among 30 (49%) individuals. Presentation to the medical aid station was sought by (62%) individuals and 9 (15%) had to stop or significantly reduce work for at least one day. Microscopy and PCR analysis of 14 stool samples collected from previously symptomatic patients, Shigella (7), Cryptosporidium (5), and Cyclospora (4) were the most prevalent pathogens detected. Consumption of food from on-base local vendors (RR = 4.01, 95% CI = 1.53–10.5, p-value <0.001) and arriving on base within the past two weeks (RR = 2.79, 95% confidence [CI] = 1.35–5.76, p-value = 0.001) were associated with increased risk of developing diarrheal disease. The risk of infectious diarrhea is great among reserve military personnel during two week training exercises. The consumption of local food, prepared without proper monitoring, is a risk factor for deployed personnel developing diarrheal illness. Additional information is needed to better understand disease risks to personnel conducting humanitarian assistance activities in the Latin America Region.     

New bioactive chalcones in propolis from El Salvador

2',3'-Dihydroxy-4,4'-dimethoxychalcone (1) and 2',3',4-trihydroxy-4'-methoxy-chalcone, two new chalcones, were isolated from propolis from El Salvador. The compounds showed significant antibacterial and antifungal activity and moderate toxicity to Artemia salina nauplii.     

The echinoderms (Echinodermata) from El Salvador

A list of echinoderms from El Salvador (tropical eastern Pacific) is presented. The results were obtained from field surveys (between the years 2000 and 2004), the scarce literature sources, and Internet information. A total of 37 species and six genera are reported. The most abundant echinoderms in rocky shores were: Phataria unifascialis, Echinometra vanbrunti, Holothuria kefersteini, as well as Astropecten armatus in soft bottoms.     

Mitochondrial Echoes of First Settlement and Genetic Continuity in El Salvador

Background

From Paleo-Indian times to recent historical episodes, the Mesoamerican isthmus played an important role in the distribution and patterns of variability all around the double American continent. However, the amount of genetic information currently available on Central American continental populations is very scarce. In order to shed light on the role of Mesoamerica in the peopling of the New World, the present study focuses on the analysis of the mtDNA variation in a population sample from El Salvador.

Methodology/Principal Findings

We have carried out DNA sequencing of the entire control region of the mitochondrial DNA (mtDNA) genome in 90 individuals from El Salvador. We have also compiled more than 3,985 control region profiles from the public domain and the literature in order to carry out inter-population comparisons. The results reveal a predominant Native American component in this region: by far, the most prevalent mtDNA haplogroup in this country (at ∼90%) is A2, in contrast with other North, Meso- and South American populations. Haplogroup A2 shows a star-like phylogeny and is very diverse with a substantial proportion of mtDNAs (45%; sequence range 16090–16365) still unobserved in other American populations. Two different Bayesian approaches used to estimate admixture proportions in El Salvador shows that the majority of the mtDNAs observed come from North America. A preliminary founder analysis indicates that the settlement of El Salvador occurred about 13,400±5,200 Y.B.P.. The founder age of A2 in El Salvador is close to the overall age of A2 in America, which suggests that the colonization of this region occurred within a few thousand years of the initial expansion into the Americas.

Conclusions/Significance

As a whole, the results are compatible with the hypothesis that today''s A2 variability in El Salvador represents to a large extent the indigenous component of the region. Concordant with this hypothesis is also the observation of a very limited contribution from European and African women (∼5%). This implies that the Atlantic slave trade had a very small demographic impact in El Salvador in contrast to its transformation of the gene pool in neighbouring populations from the Caribbean facade.     

In vitro antiplasmodial investigation of medicinal plants from El Salvador

In vitro antiplasmodial activities of extracts from Albizia saman, Fabaceae, Calea tenuifolia (C. zacatechichi), Asteraceae, Hymenaea courbaril, Fabaceae, Jatropha curcas, Euphorbiaceae, Momordica charantia, Cucurbitaceae, and Moringa oleifera, Moringaceae were evaluated. From the lipophilic extract of C tenuifolia five active flavones were obtained. 4',5-Dihydroxy-7-methoxyflavone [genkwanin] and 5-hydroxy-4',7-dimethoxyflavone [apigenin 4',7-dimethylether] exhibited the strongest antiplasmodial activity against a chloroquine-sensitive strain (poW) and a chloroquine-resistant strain (Dd2) of Plasmodium falciparum [IC50 values: 17.1-28.5 microM). Furthermore octadeca-9,12-dienoic acid [linoleic acid] [IC50] values of 21.8 microM (poW) and 31.1 microM (Dd2)] and octadeca-9,12,15-trienoic acid (alpha-linolenic acid) were isolated.     

Studies on the Santa Lucia (El Salvador) strain of Plasmodium falciparum in Aotus trivirgatus monkeys.

The Santa Lucia strain of Plasmodium falciparum was isolated from El Salvador, Central America, and established in Aotus trivirgatus monkeys. Transmission from monkey to monkey via the bites of infected Anopheles freeborni, A. maculatus, and A, albimanus mosquitoes was obtained in 20 of 27 attempts. Prepatent periods in the monkeys ranged from 17 to 46 days with a mean of 24.3 days. Parasitemias and mortality were higher following sporozoite inoculation into animals which had been previously infected with P. vivax than in those with no previous malaria experience. Monkeys previously infected with P. vivax and P. cynomolgi had lower maximum parasitemias than those previously infected with P. vivax only.     

Biological control ofAleurocanthus woglumi [Homoptera: Aleyrodidae] in El Salvador

The citrus blackfly,Aleurocanthus woglumi Ash., was first observed in El Salvador in 1965. Its dispersal was followed during a three-year period (1969–1972) in which it infested most citrus orchards in the country. Indigenous natural enemies as the predatorsDelphastus sp. andChrysopa sp., and the pathogenic fungusAschersonia aleyrodis Web. are unable to exert any economic control of the pest. The introduction of the parasiteProspaltella opulenta Silvestri from Mexico brought about the successful biological control of the pest. Life table studies carried out before and after introduction of the parasite helped to assess the value ofP. opulenta as an effective natural enemy of the citrus blackfly.

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Résumé L'Aleurode des citrus,Aleurocanthus woglumi Ash. a été observé pour la première fois en Salvador en 1965. Son extension a été suivie pendant trois ans de 1969 à 1972, au cours desquels il a envahi la plupart des vergers d'agrumes du pays. Les ennemis naturels indigènes, tels que les prédateursDelphastus sp. etChrysopa sp. ainsi que le champignon pathogèneAschersonia aleyrodis Web. ne sont pas capables d'avoir un effet économiquement satisfaisant. L'introduction du Mexique du parasiteProspaltella opulenta Silvestri a été un succès pour la lutte biologique contre ce ravageur. L'étude des tables de vie effectuée avant et après cette introduction confirme la valeur deP. opulenta comme ennemi naturel officace de l'Aleurode des citrus.

     

The red tide event in El Salvador, August 2001-January 2002

A red tide event occurred in El Salvador from August 2001 to January 2002. National health authorities usually measured toxin levels in Ostrea iridescens, however other species were analyzed during this microalgae bloom: Anadara similis, Anadara tuberculosa and Modiolus sp. El Salvador authorities consider 400 mouse units/100 g the highest value that is safe for human health. During this period toxin levels in 0. iridescens and Modiolus sp. increased from values under 400 to 3977 and 15,468 mouse units/100 g, respectively. Persistent and higher levels were recorded in oyster and mussel banks on the west part of the country. The Ministry of Health and Social Assistance treated 41 slight to moderate intoxications associated to bivalve mollusks consumption.     

Anti-inflammatory activity of two diterpenes of Hyptis suaveolens from El Salvador

Separation and isolation of the two main compounds suaveolol and methyl suaveolate from leaves of chichinguaste (Hyptis suaveolens Poit., Lamiaceae) could be achieved by means of repeated column chromatography and repeated preparative thin layer chromatography. Their chemical structures were approved by MS, 1H NMR, 13C NMR and 2D-NMR experiments. The anti-inflammatory activity of the two compounds was tested for the first time as inhibition of croton oil-induced dermatitis of the mouse ear. Suaveolol and methyl suaveolate showed nearly the same dose-dependent topical anti-inflammatory activity, only two to three times lower than that of the reference drug indomethacin. The anti-inflammatory properties of these compounds could contribute to the antiphlogistic activity of extracts of Hyptis species and confirm the rational use of Hyptis suaveolens extracts in dermatological diseases.     

Threat Assessment and Conservation Prioritization of the Herpetofauna of El Salvador

We applied the IUCN Red List method for threat assessment to the amphibians and reptiles of El Salvador, the smallest Central American country. Seventy-six out of 130 species were found to be threatened or endangered at the national level. In general, most threatened taxa were aquatic organisms in lowland habitats or cloud-forest specialists in highland areas. The IUCN method was biased by collecting effort and was unable to classify 25 species that were categorized as ȁ8data deficientȁ9. We used the number and distribution of threatened species and a complementarity analysis to identify departments in El Salvador that require higher priority for conservation action. We applied a method for evaluating inventory completeness to our data set, and used species from reasonably well-surveyed taxonomic groups (Anura and Sauria) to carryout the complementarity analysis. The anurans (frogs) and saurians (lizards) had been inventoried relatively completely in 10 of 14 departments. The department with the most threatened species (35 of 76 threatened amphibians and reptiles) is Santa Ana, where many threatened species occur in pine-oak and cloud forest in Montecristo National Park.     

Irrigation planning to transform subsistence agriculture: Lessons From El Salvador

Experience with irrigation schemes designed to improve the productivity of subsistence farmers in Latin America seems to parallel the results of the green revolution in Southeast Asia. Although in some cases the impact on the productivity has been significant, in far too many cases the pervasive pattern of inequity has been reinforced. This case study of the Irrigation District of Zapotitan in El Salvador analyses some of the reasons for the unexpected results, with particular reference to the planning process. It essentially illustrates that the transformation of subsistence agriculture through irrigation demands new institutions designed not only to service agricultural production but also to ensure the accrual of benefits on the targeted group.