Population Structure and Evidence for Both Clonality and Recombination among Brazilian Strains of the Subgenus Leishmania (Viannia)

Background/Objectives: Parasites of the subgenus Leishmania (Viannia) cause varying clinical symptoms ranging from cutaneous leishmaniases (CL) with single or few lesions, disseminated CL (DL) with multiple lesions to disfiguring forms of mucocutaneous leishmaniasis (MCL). In this population genetics study, 37 strains of L. (V.) guyanensis, 63 of L. (V.) braziliensis, four of L. (V.) shawi, six of L. (V.) lainsoni, seven of L. (V.) naiffi, one each of L. (V.) utingensis and L. (V.) lindenbergi, and one L. (V.) lainsoni/L. naiffi hybrid from different endemic foci in Brazil were examined for variation at 15 hyper-variable microsatellite markers. Methodology/Principal findings: The multilocus microsatellite profiles obtained for the 120 strains were analysed using both model- and distance-based methods. Significant genetic diversity was observed for all L. (Viannia) strains studied. The two cluster analysis approaches identified two principal genetic groups or populations, one consisting of strains of L. (V.) guyanensis from the Amazon region and the other of strains of L. (V.) braziliensis isolated along the Atlantic coast of Brazil. A third group comprised a heterogeneous assembly of species, including other strains of L. braziliensis isolated from the north of Brazil, which were extremely polymorphic. The latter strains seemed to be more closely related to those of L. (V.) shawi, L. (V.) naiffi, and L. (V.) lainsoni, also isolated in northern Brazilian foci. The MLMT approach identified an epidemic clone consisting of 13 strains of L. braziliensis from Minas Gerais, but evidence for recombination was obtained for the populations of L. (V.) braziliensis from the Atlantic coast and for L. (V.) guyanensis. Conclusions/Significance: Different levels of recombination versus clonality seem to occur within the subgenus L. (Viannia). Though clearly departing from panmixia, sporadic, but long-term sustained recombination might explain the tremendous genetic diversity and limited population structure found for such L. (Viannia) strains.     

Comparative genomic analysis of Leishmania (Viannia) peruviana and Leishmania (Viannia) braziliensis

Background

The Leishmania (Viannia) braziliensis complex is responsible for most cases of New World tegumentary leishmaniasis. This complex includes two closely related species but with different geographic distribution and disease phenotypes, L. (V.) peruviana and L. (V.) braziliensis. However, the genetic basis of these differences is not well understood and the status of L. (V.) peruviana as distinct species has been questioned by some.Here we sequenced the genomes of two L. (V.) peruviana isolates (LEM1537 and PAB-4377) using Illumina high throughput sequencing and performed comparative analyses against the L. (V.) braziliensis M2904 reference genome. Comparisons were focused on the detection of Single Nucleotide Polymorphisms (SNPs), insertions and deletions (INDELs), aneuploidy and gene copy number variations.

Results

We found 94,070 variants shared by both L. (V.) peruviana isolates (144,079 in PAB-4377 and 136,946 in LEM1537) against the L. (V.) braziliensis M2904 reference genome while only 26,853 variants separated both L. (V.) peruviana genomes.Analysis in coding sequences detected 26,750 SNPs and 1,513 indels shared by both L. (V.) peruviana isolates against L. (V.) braziliensis M2904 and revealed two L. (V.) braziliensis pseudogenes that are likely to have coding potential in L. (V.) peruviana. Chromosomal read density and allele frequency profiling showed a heterogeneous pattern of aneuploidy with an overall disomic tendency in both L. (V.) peruviana isolates, in contrast with a trisomic pattern in the L. (V.) braziliensis M2904 reference.Read depth analysis allowed us to detect more than 368 gene expansions and 14 expanded gene arrays in L. (V.) peruviana, and the likely absence of expanded amastin gene arrays.

Conclusions

The greater numbers of interspecific SNP/indel differences between L. (V.) peruviana and L. (V.) braziliensis and the presence of different gene and chromosome copy number variations support the classification of both organisms as closely related but distinct species.The extensive nucleotide polymorphisms and differences in gene and chromosome copy numbers in L. (V.) peruviana suggests the possibility that these may contribute to some of the unique features of its biology, including a lower pathology and lack of mucosal development.

Electronic supplementary material

The online version of this article (doi:10.1186/s12864-015-1928-z) contains supplementary material, which is available to authorized users.     

The Genome Sequence of Leishmania (Leishmania) amazonensis: Functional Annotation and Extended Analysis of Gene Models

We present the sequencing and annotation of the Leishmania (Leishmania) amazonensis genome, an etiological agent of human cutaneous leishmaniasis in the Amazon region of Brazil. L. (L.) amazonensis shares features with Leishmania (L.) mexicana but also exhibits unique characteristics regarding geographical distribution and clinical manifestations of cutaneous lesions (e.g. borderline disseminated cutaneous leishmaniasis). Predicted genes were scored for orthologous gene families and conserved domains in comparison with other human pathogenic Leishmania spp. Carboxypeptidase, aminotransferase, and 3′-nucleotidase genes and ATPase, thioredoxin, and chaperone-related domains were represented more abundantly in L. (L.) amazonensis and L. (L.) mexicana species. Phylogenetic analysis revealed that these two species share groups of amastin surface proteins unique to the genus that could be related to specific features of disease outcomes and host cell interactions. Additionally, we describe a hypothetical hybrid interactome of potentially secreted L. (L.) amazonensis proteins and host proteins under the assumption that parasite factors mimic their mammalian counterparts. The model predicts an interaction between an L. (L.) amazonensis heat-shock protein and mammalian Toll-like receptor 9, which is implicated in important immune responses such as cytokine and nitric oxide production. The analysis presented here represents valuable information for future studies of leishmaniasis pathogenicity and treatment.     

Nectar and pollen sources for honeybees in Kafrelsheikh province of northern Egypt

This study was conducted at the apiary of the Beekeeping Research Section at the Sakha Agricultural Research Station, ARC, Kafrelsheikh, and other apiaries in Kafrelsheikh province, during two successive years 2015 and 2016. The study aimed to survey nectar and pollen floral resources in Kafrelsheikh province. Ninty seven plant species belonging to 33 families were recorded as nectar sources, and 82 plant species belonging to 36 families were recorded as pollen sources during the whole year. The largest amount of monthly trapped pollen was obtained during May followed by August. It can be concluded that, beekeepers in Kafrelsheikh province can harvest good honey yield at the end of blooming seasons of citrus (Citrus spp.) during March and April, Egyptian clover (Trifolium alexandrinum L.) during May and June, loofah (Luffa aegyptiaca Mill.) during June to October, cotton (Gossypium spp.) during July and August, and banana (Musa spp.) during August and September. They also, could be trapping pollen loads collected from faba bean (Vicia faba L.) and flax (Linum usitatissimum L.) during January to March, date palm (Phoenix dactylifera L.) during March and April, Egyptian clover during May and June, summer seed watermelon (Citrullus lanatus var. colothynthoides L.) during June and July, loofah and maize (Zea mays L.) during June to November.     

New crop residues and forages for Western Canada: Assessment of feeding value in vitro and response to ammonia treatment

A survey was conducted on the feed value for ruminants of a variety of crop residues and forages, with particular emphasis on crop residues and forages not currently grown extensively in Western Canada. Crop residues with feed values significantly higher than wheat (Triticum aestivum L.) or barley (Hordeum vulgare L.) straw were investigated, and the response to ammonia treatment was evaluated, to determine which materials could be appreciably improved in feed value by this technique. Some of the crop residues evaluated by digestibility in vitro and crude-protein content had a significantly higher feed value, without chemical processing, than the cereal straws often given to cattle in Western Canada. Ammonia treatment improved both the organic matter digestibility in vitro and crude-protein content of some residues significantly, while other materials showed only an improvement in crude protein. The organic matter digestibility in vitro of sunflower (Helianthus annus L.) crop residue and Jerusalem-artichoke (Helianthus tuberosis L.) forage and residue was initially higher than that of alfalfa (Medicago sativa L.) or sweet clover [Melilotus officinalus (L.) Lam] and did not increase appreciably with ammonia treatment. Faba-bean (Vicia faba L.) residue was only slightly inferior to these materials and showed a moderate improvement after treatment with ammonia. Untreated bullrush-millet [Pennisetum americanum (L.) Schum] whole-crop forage was equivalent to alfalfa and sweet clover in digestibility in vitro and responded quite well to ammonia treatment. Kochia (Kochia scoparia Shrad) forage had a relatively high digestibility in vitro and crude-protein content when harvested at the flowering stage. Mature kochia had a digestibility in vitro equivalent to barley straw and did not respond well to ammonia treatment.     

Ammonium and nitrate uptake by aquatic plants from poorly buffered and acidified waters

In the Netherlands, atmospheric deposition of ammonia compounds, particularly ammonium sulphate, is an important source for the acidification of oligotrophic soft waters. As a consequence, the acidified waters are generally nitrogen enriched, ammonium being the dominant N form. In this study, it is examined how this alteration in the nitrogen household affects the aquatic plant communities in acidifying waters.The uptake of ammonium and nitrate by leaves and roots of two groups of freshwater plants has been studied using glass incubation chambers. The forst group (Littorella uniflora (L.) Aschers.; Lobelia dortmanna L.; Luronium natans (L.) Raf.; Echinodorus ranunculoides (L.) Engelm.) is characteristic of nitrogen-poor soft waters, whereas the second group (Juncus bulbosus L.; Sphagnum flexuosum Dozy & Molk.;Agrostis canina L.; Drepanocladus fluitans (Hedw.) Warnst.) often occurs in dense stands in nitrogen-enriched, acid waters. Both groups have typical adaptations to the nitrogen condition of their aquatic environment. The soft-water species show a nitrate-dominated (63–73%) nitrogen utilization, with the roots as the major (83%) uptake site. Moreover, they are able to survive at very low nitrogen concentrations. The acid-tolerant species have an ammonium-dominated (85–90%) nitrogen utilization, with the leaves as the major (71–82%) uptake site. This group profits from the increased ammonium levels in acid waters. It is concluded that in the case of acidification increased ammonium concentrations additionally account for the suppression of typical soft-water communities by communities dominated by Juncus bulbosus and Sphagnum spp.     

Constitutive nitric oxide synthase-like enzyme in two species involved in cutaneous and mucocutaneous leishmaniasis

Leishmania is an obligate intracellular parasite that primarily inhabits macrophages. The destruction of the parasite in the host cell is a fundamental mechanism for infection control. In addition, inhibition of the leishmanicidal activity of macrophages seems to be related to the ability of some species to inhibit the production of nitric oxide (NO) by depleting arginine. Some species of Leishmania have the ability to produce NO from a constitutive nitric oxide synthase-like enzyme (cNOS-like). However, the localization of cNOS-like in Leishmania has not been described before. As such, this study was designed to locate cNOS-like enzyme and NO production in promastigotes of Leishmania (Leishmania) amazonensis and Leishmania (Viannia) braziliensis. NO production was initially quantified by flow cytometry, which indicated a significant difference in NO production between L. (L.) amazonensis (GMFC = 92.17 +/− 4.6) and L. (V.) braziliensis (GMFC = 18.89 +/− 2.29) (P < 0.05). Analysis of cNOS expression by immunoblotting showed more expression in L. (L.) amazonensis versus L. (V.) braziliensis. Subsequently, cNOS-like immunolabeling was observed in promastigotes in regions near vesicles, the flagellar pocket and mitochondria, and small clusters of particles appeared to be fusing with vesicles suggestive of glycosomes, peroxisome-like-organelles that compartmentalize the glycolytic pathway in trypanosomatid parasites. In addition, confocal microscopy analysis demonstrated colocalization of cNOS-like and GAPDH, a specific marker for glycosomes. Thus, L. (L.) amazonensis produces greater amounts of NO than L. (V.) braziliensis, and both species present the cNOS-like enzyme inside glycosomes.     

Effects of pH,water stress and temperature on in vitro cultures of ectomycorrhizal fungi from Mediterranean forests

A comparative study of the growth of eight species of ectomycorrhizal fungi [Hebeloma edurum Métrod ex Bon, Lactarius deliciosus (L.: Fr.) S.F. Gray., Rhizopogon roseolus (Corda) Th.M.Fr., Suillus collinitus (Fr.) Kuntze, Suillus granulatus (L.: Fr.) Roussel, Suillus luteus (L.: Fr.) Roussel, Tricholoma focale (Fr.) Ricken, Tricholoma striatum (Schaeff.) Sacc.] in pure culture at different pH values, water potentials and temperatures was carried out. The biomass production and mycelial growth of each strain were assessed and characterised morphologically. H. edurum and L. deliciosus showed a clear affinity for neutral or slightly basic media. Most species had the lowest colony diameters and biomass production at pH 2.5. Only H. edurum, R. roseolus and S. collinitus grew at the highest water stress levels (−13.85 and −15.45 bar). All species grew at the lowest values of temperature whereas only R. roseolus and S. collinitus did at 30 °C.     

Pollen morphology of Lathyrus (Fabaceae) taxa in the Platystylis section from Turkey

In this study, the pollen morphology of 18 wild taxa of Lathyrus L. grown in Turkey: L. pallescens (Bieb.) Koch, L. brachypterus Cel., L. haussknechtii Sirj., L. karsianus P. H. Davis, L. satdaghensis P. H. Davis, L. nivalis Hand.-Mazz, L. atropatanus (Grossh.) Sir., L. armenus (Boiss. and Huet) Sirj., L. cyaneus (Stev.) Koch var. cyaneus, L. cyaneus var. pinnatus?Davis, L. digitatus (Bieb.) Fiori, L. tukhtensis Czecz., L. variabilis (Boiss. and Ky.) Maly, L. spathulatus Cel. L. elongatus (Bornm.) Sirj., L. cilicicus Hayek and Siehe, L. boissieri Sirj., and L. bitlisicus Pe?men was examined by light microscopy and scanning electron microscopy. The pollen grains were 3-zonocolporate, of spheroidal-subprolate-prolate (P/E?=?0.957?C1.252) types, and medium in size. Equatorial view: rectangular or elliptical-obtuse-convex, polar view: circular, triangular or quinquangular-obtuse-convex. The smallest pollen grains belonged to L. elongatus (P?=?36.972/E?=?38.636) and the largest to L. cyaneus var. cyaneus (P?=?46.332/E?=?32.864). The ornamentation was perforate-foveolate or slightly reticulate. Some photographs included in this work were taken using both light microscopy and scanning electron microscopy.     

In Vitro and In Vivo Activity of an Organic Tellurium Compound on Leishmania (Leishmania) chagasi

Tellurium compounds have shown several biological properties and recently the leishmanicidal effect of one organotellurane was demonstrated. These findings led us to test the effect of the organotellurium compound RF07 on Leishmania (Leishmania) chagasi, the agent of visceral leishmaniasis in Latin America. In vitro assays were performed in L. (L.) chagasi-infected bone marrow derived macrophages treated with different concentrations of RF07. In in vivo experiments Golden hamsters were infected with L. (L.) chagasi and injected intraperitoneally with RF07 whereas control animals received either Glucantime or PBS. The effect of RF07 on cathepsin B activity of L. (L.) chagasi amastigotes was assayed spectrofluorometrically using fluorogenic substrates. The main findings were: 1) RF07 showed significant leishmanicidal activity against intracellular parasites at submicromolar concentrations (IC50 of 529.7±26.5 nM), and the drug displayed 10-fold less toxicity to macrophages (CC50 of 5,426±272.8 nM); 2) kinetics assays showed an increasing leishmanicidal action of RF07 at longer periods of treatment; 3) one month after intraperitoneal injection of RF07 L. (L.) chagasi-infected hamsters showed a reduction of 99.6% of parasite burden when compared to controls that received PBS; 4) RF07 inhibited the cathepsin B activity of L. (L.) chagasi amastigotes. The present results demonstrated that the tellurium compound RF07 is able to destroy L. (L.) chagasi in vitro and in vivo at concentrations that are non toxic to the host. We believe these findings support further study of the potential of RF07 as a possible alternative for the chemotherapy of visceral leishmaniasis.     

Mucosal Leishmaniasis caused by Leishmania (Viannia) braziliensis and Leishmania (Viannia) guyanensis in the Brazilian Amazon

Background

Leishmania (Viannia) braziliensis is a parasite recognized as the most important etiologic agent of mucosal leishmaniasis (ML) in the New World. In Amazonia, seven different species of Leishmania, etiologic agents of human Cutaneous Leishmaniasis, have been described. Isolated cases of ML have been described for several different species of Leishmania: L. (V.) panamensis, L. (V.) guyanensis and L. (L.) amazonensis.

Methodology

Leishmania species were characterized by polymerase chain reaction (PCR) of tissues taken from mucosal biopsies of Amazonian patients who were diagnosed with ML and treated at the Tropical Medicine Foundation of Amazonas (FMTAM) in Manaus, Amazonas state, Brazil. Samples were obtained retrospectively from the pathology laboratory and prospectively from patients attending the aforementioned tertiary care unit.

Results

This study reports 46 cases of ML along with their geographical origin, 30 cases caused by L. (V.) braziliensis and 16 cases by L. (V.) guyanensis. This is the first record of ML cases in 16 different municipalities in the state of Amazonas and of simultaneous detection of both species in 4 municipalities of this state. It is also the first record of ML caused by L. (V.) guyanensis in the states of Pará, Acre, and Rondônia and cases of ML caused by L. (V.) braziliensis in the state of Rondônia.

Conclusions/Significance

L. (V.) braziliensis is the predominant species that causes ML in the Amazon region. However, contrary to previous studies, L. (V.) guyanensis is also a significant causative agent of ML within the region. The clinical and epidemiological expression of ML in the Manaus region is similar to the rest of the country, although the majority of ML cases are found south of the Amazon River.

Author Summary

Leishmaniasis is considered a neglected disease with 1.5 million new cases of cutaneous leishmaniasis (CL) occurring each year. In the Amazon region and in the Americas in general, ML is caused by Leishmania (Viannia) braziliensis, though in rare cases it has been related to other species. ML, which is associated with inadequate treatment of CL, normally manifests itself years after the occurrence of CL. Clinical features evolve slowly and most often affect the nasal cavity, in some cases causing perforation, or even destruction, of the septum. Diagnosis is made using the Montenegro skin test, serology and histopathology of the patients'' mucosal tissues, or by isolation of the parasites. PCR is the best way to identify the species of leishmaniasis and is therefore the diagnostic method of choice. This paper describes 46 cases of ML and their geographical origin, 30 cases associated with L. (V.) braziliensis and 16 with L. (V.) guyanensis. The species of leishmaniasis was identified using mucosal biopsies taken from Amazonian patients who were diagnosed and treated for ML in the tertiary care unit, in Manaus, Amazonas state, Brazil. This is the highest number of ML cases caused by L. (V.) guyanensis that has ever been reported.     

Pollen morphology of Lathyrus (Leguminosae) taxa belonging to Lathyrus, Orobastrum and Cicercula sections from Turkey

The pollen morphology of 20 wild taxa belonging to Lathyrus (Syn: Eulathyrus), Orobastrum (Taub.) Boiss. and Cicercula (Medic.) Gren. & Godr. sections of Lathyrus L. grown in Turkey (L. rotundifolius Wild. subsp. miniatus (Bieb. ex Steven) P.H. Davis, L. grandiflorus Sibth. & Sm., L. saxatilis (Vent.) Vis., L. vinealis Boiss. & No?, L. inconspicuus L. var. inconspicuus, L. inconspicuus var. stenophyllus (Boiss.) Rech. f., L. tauricola P.H. Davis, L. woronowii Bornm., L. hierosolymitanus Boiss., L. cassius Boiss., L. gorgoni Parl. var. gorgoni, L. pseudo-cicera Pamp., L. sativus L., L. blepharicarpus Boiss., L. stenophyllus Boiss. & Heldr., L. belinensis Maxted & Goyder, L. phaselitanus Hub.-Mor. & P.H.Davis, L. chrysanthus Boiss., L. chloranthus Boiss., and L. trachycarpus (Boiss.) Boiss were examined by light microscopy (LM) and scanning electron microscopy (SEM) in this study. The pollen grains were 3-zonocolporate, spheroidal, subprolate, and prolate (P/E?=?0.99–1.48) types, and were medium in size (equatorial view: rectangular or elliptical-obtuse-convex; polar view: circular, triangular and quinquangular-obtuse-convex). The smallest pollen grains belonged to L. tauricola (P?=?30.94/E?=?31.20) and the largest to L. grandiflorus (P?=?50.60/E?=?36.40). The ornamentation was reticulate and reticulate-granulate in the mesocolpium, and usually psilate in the apocolpium. Some photographs included in this work were taken using both LM and SEM.     

A review of sciarids of the genus <Emphasis Type="Italic">Leptosciarella</Emphasis> Tuomikoski 1960 (Diptera,Sciaridae) in the Altai fauna,with description of three new species

The taxonomy of the genus Leptosciarella Tuomikoski, 1960 in the Altai Area within Altai Territory and the Altai Republic was studied. Eleven species were recognized, including three new species which are described and illustrated here: Leptosciarella (L.) ulagana Komarova sp. n., L. (L.) angustistylus Komarova sp. n., L. (L.) senex Komarova sp. n. Additionally, L. (L.) fuscipalpa (Mohrig et Mamaev 1979) and L. (L.) truncata (Tuomikoski 1960) are recorded from Altai for the first time. A key to the Altai species is provided.     

Effect of seven species of the family Asteraceae on longevity and nutrient levels of Episyrphus balteatus

Adult hoverflies feed on pollen, nectar and honeydews. Thus, the implementation of floristically diverse resources in agroecosystems can enhance biological control of pests by increasing populations of these natural enemies. The objective of this work was to study the effect of seven species of Asteraceae (Andryala integrifolia L., Anthemis arvensis L., Calendula arvensis L., Carduus tenuiflorus Curtis, Chamaemelum nobile (L.) All., Coleostephus myconis (L.) Rchb.f. and Crepis vesicaria L.) on adult longevity and nutrient levels of Episyrphus balteatus (De Geer) (Diptera: Syrphidae). Crepis vesicaria and C. nobile gave the highest mean longevities while, for the other plant species, longevities were not significantly different from those in the water only treatment. In addition, all species tested resulted in significantly lower longevities than the positive control (glucose). In terms of nutrient levels, C. nobile generated high levels of total sugars and C. vesicaria high levels of lipids which suggests the consumption of flower resources. However, the majority of the plants tested would not allow hoverflies to complete their life cycle. Thus, further experimentation needs to be done before considering these plants for implementation in agroecosystems.     

The effect of sodium chloride on enzyme activities from four halophyte species of chenopodiaceae

The in vitro effect of sodium chloride on the enzyme activity of four halophytes, Beta vulgaris ssp. maritima (L.) Thell., Halimione portulacoides (L.) Aell., Salicornia ramosissima Woods and Suaeda maritima (L.) Dum. was investigated. The activity was, in general, affected by sodium chloride in a similar manner to that reported for salt sensitive species. The most notable exceptions were the sodium chloride stimulated ATPases of Beta and Salicornia.     

Chloroplast Biogenesis 49 : Differences among Angiosperms in the Biosynthesis and Accumulation of Monovinyl and Divinyl Protochlorophyllide during Photoperiodic Greening

Various angiosperms differed in their monovinyl and divinyl protochlorophyllide biosynthetic capabilities during the dark and light phases of photoperiodic growth. Some plant species such as Cucumis sativus L., Brassica juncea (L.) Coss., Brassica kaber (DC.) Wheeler, and Portulaca oleracea L. accumulated mainly divinyl protochlorophyllide at night. Monocotyledonous species such as Avena sativa L., Hordeum vulgare L., Triticum secale L., Zea mays L., and some dicotyledonous species such as Phaseolus vulgaris L., Glycine max (L.) Merr., Chenopodium album L., and Lycopersicon esculentum L. accumulated mainly monovinyl protochlorophyllide at night.

Under low light intensities meant to simulate the first 60 to 80 minutes following daybreak divinyl protochlorophyllide appeared to contribute much more to chlorophyll formation than monovinyl protochlorophyllide in species such as Cucumis sativus L. Under the same light conditions, species which accumulated mainly monovinyl protochlorophyllide at night appeared to form chlorophyll preferably via monovinyl protochlorophyllide.

These results were interpreted in terms of: (a) a differential contribution of monovinyl and divinyl protochlorophyllide to chlorophyll formation at daybreak in various plant species; and (b) a differential regulation of the monovinyl and divinyl protochlorophyllide biosynthetic routes by light and darkness.

     

Endogenous Plant Growth Substances in Developing Fruit of Prunus cerasus L: VII. Isolation of Gibberellin A(32)

A polar gibberellin active in the dwarf rice (Oryza sativa L.) seedling and barley (Hordeum vulgare L.) half-seed assays was extracted from immature sour cherry (Prunus cerasus L.) seed and identified as gibberellin A₃₂ by gas-liquid chromatography and selected ion monitoring.     

Insight into the structure and chemistry of glandular trichomes of Labiatae, with emphasis on subfamily Lamioideae

Glandular trichomes of Labiatae are among the most investigated secretory structures. Most species studied belong to subfamily Nepetoidae, including plants with aromatic properties, while so far a few species of subfamily Lamioideae were examined. In this work, we studied the micromorphology, ultrastructure, type and release of secretion of the glandular trichomes present on leaves and flowers of several species belonging to subfamily Lamioideae, (Stachys alopecuros (L.) Bentham subsp. alopecuros, S. officinalis (L.) Trevisan subsp. officinalis, S. germanica L. subsp. germanica, S. germanica L. subsp. salviifolia (Ten.) Gams, S. sylvatica L., S. heraclea All., S. plumosa Griseb., S. annua L., Prasium majus L., Sideritis romana L.) and one to the sister group Scutellarioideae (Scutellaria galericulata L.). Besides the well-known peltate and small capitate trichomes, widely described in the literature, other types of glandular trichomes were encountered; stalked peltate hairs and large capitate hairs. In particular, a new type of capitate trichome, exclusive of calices and corollas, which presents a mode and release of secretion never described before, is reported.     

In vitro and in vivo activity of a palladacycle complex on Leishmania (Leishmania) amazonensis

Background

Antitumor cyclopalladated complexes with low toxicity to laboratory animals have shown leishmanicidal effect. These findings stimulated us to test the leishmanicidal property of one palladacycle compound called DPPE 1.2 on Leishmania (Leishmania) amazonensis, an agent of simple and diffuse forms of cutaneous leishmaniasis in the Amazon region, Brazil.

Methodology/Principal Findings

Promastigotes of L. (L.) amazonensis and infected bone marrow-derived macrophages were treated with different concentrations of DPPE 1.2. In in vivo assays foot lesions of L. (L.) amazonensis-infected BALB/c mice were injected subcutaneously with DPPE 1.2 and control animals received either Glucantime or PBS. The effect of DPPE 1.2 on cathepsin B activity of L. (L.) amazonensis amastigotes was assayed spectrofluorometrically by use of fluorogenic substrates. The main findings were: 1) axenic L. (L.) amazonensis promastigotes were destroyed by nanomolar concentrations of DPPE 1.2 (IC50 = 2.13 nM); 2) intracellular parasites were killed by DPPE 1.2 (IC50 = 128.35 nM), and the drug displayed 10-fold less toxicity to macrophages (CC50 = 1,267 nM); 3) one month after intralesional injection of DPPE 1.2 infected BALB/c mice showed a significant decrease of foot lesion size and a reduction of 97% of parasite burdens when compared to controls that received PBS; 4) DPPE 1.2 inhibited the cysteine protease activity of L. (L.) amazonensis amastigotes and more significantly the cathepsin B activity.

Conclusions/Significance

The present results demonstrated that DPPE 1.2 can destroy L. (L.) amazonensis in vitro and in vivo at concentrations that are non toxic to the host. We believe these findings support the potential use of DPPE 1.2 as an alternative choice for the chemotherapy of leishmaniasis.     

Taxonomic significance of trichomes micromorphology in cucurbits

Studies on trichomes micromorphology using Scanning Electron Microscope (SEM) were undertaken in 23 species with one variety under 13 genera of the family Cucurbitaceae (viz., Benincasa hispida (Thunb.) Cogn., Citrullus lanatus (Thunb.) Matsum. & Nakai, Cucumis melo var. agrestis Naudin, Cucumis sativus L., Diplocyclos palmatus (L.) C. Jeffrey, Edgaria dargeelingensis C.B. Clarke, Gynostemma burmanicum King ex Chakr., Gynostemma pentaphyllum (Thunb.) Makino, Gynostemma pubescens (Gagnep.) C.Y. Wu, Hemsleya dipterygia Kuang & A.M. Lu, Lagenaria siceraria (Molina) Standl., Luffa acutangula (L.) Roxb., Luffa cylindrica M. Roem., Luffa echinata Roxb., Melothria heterophylla (Lour.) Cogn., Melothria leucocarpa (Blume) Cogn., Melothria maderspatana (L.) Cogn., Sechium edule (Jacq.) Sw., Thladiantha cordifolia (Blume) Cogn., Trichosanthes cucumerina L., T. cucumerina var. anguina (L.) Haines, Trichosanthes dioica Roxb., Trichosanthes lepiniana (Naudin) Cogn. and T. tricuspidata Lour.). The trichomes in the family Cucurbitaceae vary from unicellular to multicellular, conical to elongated, smooth to ridges, with or without flattened disk at base and cyctolithic appendages, thin to thick walled, curved at apices to blunt. Trichomes micromorphology in the family Cucurbitaceae was found significant taxonomically.