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Endomelanconiopsis, a new anamorph genus in the Botryosphaeriaceae
Get PDFA new lineage is discovered within the Botryosphaeriaceae (Ascomycetes, Dothideomycetes, incertae sedis). Consistent with current practice of providing generic names for independent lineages, this lineage is described as Endomelanconiopsis gen. nov., with the anamorphic species E. endophytica sp. nov. and E. microspora comb. nov. (5 Endomelanconium microsporum). Endomelanconiopsis is characterized by eustromatic conidiomata and holoblastically produced, brown, nonapiculate, unicellular conidia, each with a longitudinal germ slit. Phylogenetic analysis of partial sequences of LSU, ITS and translation elongation factor 1 alpha (tef1) indicate that E. endophytica is sister of E. microspora and that they are nested within the Botryosphaeriaceae. However because there is no support for the ‘‘backbone’’ of the Botryosphaeriacae we are not able to see the interrelationships among the many genera in the family. Neither species is known to have a teleomorph. Endomelanconiopsis differs from Endomelanconium because conidia of the type species of Endomelanconium, E. pini, are papillate at the base, conidiogenous cells proliferate sympodially and the pycnidial wall is thinner; we postulate that the teleomorph of E. pini as yet unknown is an inoperculate discomycete. Endomelanconiopsis endophytica was isolated as an endophyte from healthy leaves of Theobroma cacao (cacao, Malvaceae) and Heisteria concinna (Erythroplaceae) in Panama. Endomelanconiopsis microspora was isolated from soil in EuropeA new lineage is discovered within the Botryosphaeriaceae (Ascomycetes, Dothideomycetes, incertae sedis). Consistent with current practice of providing generic names for independent lineages, this lineage is described as Endomelanconiopsis gen. nov., with the anamorphic species E. endophytica sp. nov. and E. microspora comb. nov. (5 Endomelanconium microsporum). Endomelanconiopsis is characterized by eustromatic conidiomata and holoblastically produced, brown, nonapiculate, unicellular conidia, each with a longitudinal germ slit. Phylogenetic analysis of partial sequences of LSU, ITS and translation elongation factor 1 alpha (tef1) indicate that E. endophytica is sister of E. microspora and that they are nested within the Botryosphaeriaceae. However because there is no support for the ‘‘backbone’’ of the Botryosphaeriacae we are not able to see the interrelationships among the many genera in the family. Neither species is known to have a teleomorph. Endomelanconiopsis differs from Endomelanconium because conidia of the type species of Endomelanconium, E. pini, are papillate at the base, conidiogenous cells proliferate sympodially and the pycnidial wall is thinner; we postulate that the teleomorph of E. pini as yet unknown is an inoperculate discomycete. Endomelanconiopsis endophytica was isolated as an endophyte from healthy leaves of Theobroma cacao (cacao, Malvaceae) and Heisteria concinna (Erythroplaceae) in Panama. Endomelanconiopsis microspora was isolated from soil in Europ
A review on the wettability of dental implant surfaces I: Theoretical and experimental aspects
Get PDFThe surface wettability of biomaterials determines the biological cascade of events at the biomaterial/ host interface. Wettability is modulated by surface characteristics, such as surface chemistry and surface topography. However, the design of current implant surfaces focuses mainly on specific micro- and nanotopographical features, and is still far from predicting the concomitant wetting behavior. There is an increasing interest in understanding the wetting mechanisms of implant surfaces and the role of wettability in the biological response at the implant/bone or implant/soft tissue interface. Fundamental knowledge related to the influence of surface roughness (i.e. a quantification of surface topography) on titanium and titanium alloy surface wettability, and the different associated wetting regimes, can improve our understanding of the role of wettability of rough implant surfaces on the biological outcome. Such an approach has been applied to biomaterial surfaces only in a limited way. Focusing on titanium dental and orthopaedic implants, the present study reviews the current knowledge on the wettability of biomaterial surfaces, encompassing basic and applied aspects that include measurement techniques, thermodynamic aspects of wetting and models predicting topographical and roughness effects on the wetting behavior.The surface wettability of biomaterials determines the biological cascade of events at the biomaterial/ host interface. Wettability is modulated by surface characteristics, such as surface chemistry and surface topography. However, the design of current implant surfaces focuses mainly on specific micro- and nanotopographical features, and is still far from predicting the concomitant wetting behavior. There is an increasing interest in understanding the wetting mechanisms of implant surfaces and the role of wettability in the biological response at the implant/bone or implant/soft tissue interface. Fundamental knowledge related to the influence of surface roughness (i.e. a quantification of surface topography) on titanium and titanium alloy surface wettability, and the different associated wetting regimes, can improve our understanding of the role of wettability of rough implant surfaces on the biological outcome. Such an approach has been applied to biomaterial surfaces only in a limited way. Focusing on titanium dental and orthopaedic implants, the present study reviews the current knowledge on the wettability of biomaterial surfaces, encompassing basic and applied aspects that include measurement techniques, thermodynamic aspects of wetting and models predicting topographical and roughness effects on the wetting behavior
Tuberculosis remains a challenge despite economic growth in Panama
Get PDFTuberculosis (TB) is a disease associated with inequality, and wise investment of economic resources is considered critical to its control. Panama has recently secured its status as an upper-middle-income country with robust economic growth. However, the prioritisation of resources for TB control remains a major challenge. In this article, we highlight areas that urgently require action to effectively reduce TB burden to minimal levels. Our conclusions suggest the need for fund allocation and a multidisciplinary approach to ensure prompt laboratory diagnosis, treatment assurance and workforce reinforcement, complemented by applied and operational research, development and innovation.Tuberculosis (TB) is a disease associated with inequality, and wise investment of economic resources is considered critical to its control. Panama has recently secured its status as an upper-middle-income country with robust economic growth. However, the prioritisation of resources for TB control remains a major challenge. In this article, we highlight areas that urgently require action to effectively reduce TB burden to minimal levels. Our conclusions suggest the need for fund allocation and a multidisciplinary approach to ensure prompt laboratory diagnosis, treatment assurance and workforce reinforcement, complemented by applied and operational research, development and innovation
Anti-malarial activity and HS-SPME-GC-MS chemical profiling of Plinia cerrocampanensis leaf essential oil
Get PDFBackground Plinia cerrocampanensis is an endemic plant of Panama. The leaf essential oil of this plant has shown antibacterial activity. However, anti-malarial activity and chemical profiling by HS-SPME-GC-MS of this essential oil have not been reported before.
Methods Anti-malarial activity of the essential oil (EO) was evaluated in vitro against chloroquine-sensitive HB3 and chloroquine-resistant W2 strains of Plasmodium falciparum. Synergistic effect of chloroquine and the EO on parasite growth was evaluated by calculating the combination index. A methodology involving headspace solid phase microextraction and gas chromatography-mass spectrometry (HS-SPME-GC-MS) was developed to investigate the composition of Plinia cerrocampanensis EO.
Results Plinia cerrocampanensis EO showed a high anti-malarial activity and a synergistic interaction with chloroquine. The Plinia cerrocampanensis EO inhibited P. falciparum growth in vitro at an IC50 of 7.3 μg/mL. Chloroquine together with the EO decreased the IC50 of chloroquine from 0.1 μg/mL to 0.05 μg/mL, and of the EO from 7.3 μg/mL to 1.1 μg/mL. The measured combination index was 0.58, which clearly indicates that the EO acts synergistically with chloroquine. Since the EO maintained its inhibitory activity on the chloroquine-sensitive strain of the parasite, it could be acting by a different mechanism of action than chloroquine. The best HS-SPME-GC-MS analytical conditions were obtained when the temperature of extraction was 49°C, incubation time 14 min, and the time of extraction 10 min. This method allowed for the identification of 53 volatile constituents in the EO, including new compounds not reported earlier.
Conclusions The anti-malarial activity exhibited by the Plinia cerrocampanensis EO may lend support for its possible use as an alternative for anti-malarial therapy.Background Plinia cerrocampanensis is an endemic plant of Panama. The leaf essential oil of this plant has shown antibacterial activity. However, anti-malarial activity and chemical profiling by HS-SPME-GC-MS of this essential oil have not been reported before.
Methods Anti-malarial activity of the essential oil (EO) was evaluated in vitro against chloroquine-sensitive HB3 and chloroquine-resistant W2 strains of Plasmodium falciparum. Synergistic effect of chloroquine and the EO on parasite growth was evaluated by calculating the combination index. A methodology involving headspace solid phase microextraction and gas chromatography-mass spectrometry (HS-SPME-GC-MS) was developed to investigate the composition of Plinia cerrocampanensis EO.
Results Plinia cerrocampanensis EO showed a high anti-malarial activity and a synergistic interaction with chloroquine. The Plinia cerrocampanensis EO inhibited P. falciparum growth in vitro at an IC50 of 7.3 μg/mL. Chloroquine together with the EO decreased the IC50 of chloroquine from 0.1 μg/mL to 0.05 μg/mL, and of the EO from 7.3 μg/mL to 1.1 μg/mL. The measured combination index was 0.58, which clearly indicates that the EO acts synergistically with chloroquine. Since the EO maintained its inhibitory activity on the chloroquine-sensitive strain of the parasite, it could be acting by a different mechanism of action than chloroquine. The best HS-SPME-GC-MS analytical conditions were obtained when the temperature of extraction was 49°C, incubation time 14 min, and the time of extraction 10 min. This method allowed for the identification of 53 volatile constituents in the EO, including new compounds not reported earlier.
Conclusions The anti-malarial activity exhibited by the Plinia cerrocampanensis EO may lend support for its possible use as an alternative for anti-malarial therapy
New Perspectives on Oxidized Genome Damage and Repair Inhibition by Pro-Oxidant Metals in Neurological Diseases
Get PDFThe primary cause(s) of neuronal death in most cases of neurodegenerative diseases, including Alzheimer’s and Parkinson’s disease, are still unknown. However, the association of certain etiological factors, e.g., oxidative stress, protein misfolding/aggregation, redox metal accumulation and various types of damage to the genome, to pathological changes in the affected brain region(s) have been consistently observed. While redox metal toxicity received major attention in the last decade, its potential as a therapeutic target is still at a cross-roads, mostly because of the lack of mechanistic understanding of metal dyshomeostasis in affected neurons. Furthermore, previous studies have established the role of metals in causing genome damage, both directly and via the generation of reactive oxygen species (ROS), but little was known about their impact on genome repair. Our recent studies demonstrated that excess levels of iron and copper observed in neurodegenerative disease-affected brain neurons could not only induce genome damage in neurons, but also affect their repair by oxidatively inhibiting NEIL DNA glycosylases, which initiate the repair of oxidized DNA bases. The inhibitory effect was reversed by a combination of metal chelators and reducing agents, which underscore the need for elucidating the molecular basis for the neuronal toxicity of metals in order to develop effective therapeutic approaches. In this review, we have focused on the oxidative genome damage repair pathway as a potential target for reducing pro-oxidant metal toxicity in neurological diseases.The primary cause(s) of neuronal death in most cases of neurodegenerative diseases, including Alzheimer’s and Parkinson’s disease, are still unknown. However, the association of certain etiological factors, e.g., oxidative stress, protein misfolding/aggregation, redox metal accumulation and various types of damage to the genome, to pathological changes in the affected brain region(s) have been consistently observed. While redox metal toxicity received major attention in the last decade, its potential as a therapeutic target is still at a cross-roads, mostly because of the lack of mechanistic understanding of metal dyshomeostasis in affected neurons. Furthermore, previous studies have established the role of metals in causing genome damage, both directly and via the generation of reactive oxygen species (ROS), but little was known about their impact on genome repair. Our recent studies demonstrated that excess levels of iron and copper observed in neurodegenerative disease-affected brain neurons could not only induce genome damage in neurons, but also affect their repair by oxidatively inhibiting NEIL DNA glycosylases, which initiate the repair of oxidized DNA bases. The inhibitory effect was reversed by a combination of metal chelators and reducing agents, which underscore the need for elucidating the molecular basis for the neuronal toxicity of metals in order to develop effective therapeutic approaches. In this review, we have focused on the oxidative genome damage repair pathway as a potential target for reducing pro-oxidant metal toxicity in neurological diseases
American Cutaneous Leishmaniasis in Panama: a historical review of entomological studies on anthropophilic Lutzomyia sand fly species
Get PDFWe review existing information on the epidemiology of American Cutaneous Leishmaniasis (ACL) in Panama, with emphasis on the bionomics of anthropophilic Lutzomyia sand fly species. Evidence from Panamanian studies suggests that there are six anthropophilic species in the country: Lutzomyia trapidoi, Lu. panamensis, Lu. gomezi, Lu. ylephiletor, Lu. sanguinaria and Lu. pessoana (Henceforth Lu. carrerai thula). In general, these taxa are abundant, widespread and feed opportunistically on their hosts, which make them potential transmitters of pathogens to a broad range of wildlife, domesticated animals and humans. Furthermore, nearly all man-biting species in Panama (with the exception of Lu. gomezi) expand demographically during the rainy season when transmission is likely higher due to elevated Leishmania infection rates in vector populations. Despite this, data on the distribution and prevalence of ACL suggest little influence of vector density on transmission intensity. Apart from Lu. trapidoi, anthropophilic species seem to be most active in the understory, but vertical stratification, as well as their opportunistic feeding behavior, could vary geographically. This in turn seems related to variation in host species composition and relative abundance across sites that have experienced different degrees of human alteration (e.g., deforestation) in leishmaniasis endemic regions of Panama.We review existing information on the epidemiology of American Cutaneous Leishmaniasis (ACL) in Panama, with emphasis on the bionomics of anthropophilic Lutzomyia sand fly species. Evidence from Panamanian studies suggests that there are six anthropophilic species in the country: Lutzomyia trapidoi, Lu. panamensis, Lu. gomezi, Lu. ylephiletor, Lu. sanguinaria and Lu. pessoana (Henceforth Lu. carrerai thula). In general, these taxa are abundant, widespread and feed opportunistically on their hosts, which make them potential transmitters of pathogens to a broad range of wildlife, domesticated animals and humans. Furthermore, nearly all man-biting species in Panama (with the exception of Lu. gomezi) expand demographically during the rainy season when transmission is likely higher due to elevated Leishmania infection rates in vector populations. Despite this, data on the distribution and prevalence of ACL suggest little influence of vector density on transmission intensity. Apart from Lu. trapidoi, anthropophilic species seem to be most active in the understory, but vertical stratification, as well as their opportunistic feeding behavior, could vary geographically. This in turn seems related to variation in host species composition and relative abundance across sites that have experienced different degrees of human alteration (e.g., deforestation) in leishmaniasis endemic regions of Panama
The lipid content and fatty acid composition of four eastern central Pacific native fish species
Get PDFFish is an important source of nutritious n-3 fatty acids, which are necessary for the prevention of cardiovascular and neurological diseases. The lipid content and fatty acid composition of economically important fishes from the eastern central Pacific, namely, Caranx caballus, Cynoscion phoxocephalus, Lutjanus guttatus and Scomberomorus sierra, were determined. Seasonal variations in their n-3 fatty acid composition were investigated as well. The lipid content of all these fish species was less than 4% by weight. In general, the studied species have moderate proportions of n-3 fatty acids. C. caballus was the fish species with the highest concentration of eicosapentaenoic acid (EPA) plus docosahexaenoic acid (DHA) (898 mg/100 g) followed by S. sierra (596 mg/100 g), C. phoxocephalus (421 mg/100 g) and L. guttatus (342 mg/100 g). The n-3/n-6 ratio of all the species studied ranged from 4.86 to 8.12. Results of this study indicate that all these fish species are highly recommended as a source of low calorie food that can meet the n-3 fatty acid dietary requirements of the Panamanian population.Fish is an important source of nutritious n-3 fatty acids, which are necessary for the prevention of cardiovascular and neurological diseases. The lipid content and fatty acid composition of economically important fishes from the eastern central Pacific, namely, Caranx caballus, Cynoscion phoxocephalus, Lutjanus guttatus and Scomberomorus sierra, were determined. Seasonal variations in their n-3 fatty acid composition were investigated as well. The lipid content of all these fish species was less than 4% by weight. In general, the studied species have moderate proportions of n-3 fatty acids. C. caballus was the fish species with the highest concentration of eicosapentaenoic acid (EPA) plus docosahexaenoic acid (DHA) (898 mg/100 g) followed by S. sierra (596 mg/100 g), C. phoxocephalus (421 mg/100 g) and L. guttatus (342 mg/100 g). The n-3/n-6 ratio of all the species studied ranged from 4.86 to 8.12. Results of this study indicate that all these fish species are highly recommended as a source of low calorie food that can meet the n-3 fatty acid dietary requirements of the Panamanian population
A review of therapeutic effects of mesenchymal stem cell secretions and induction of secretory modification by different culture methods
Get PDFThe mesenchymal stem cell (MSC) is being broadly studied in clinical trials. Contrary to the early paradigm of cell replacement and differentiation as a therapeutic mechanism of action, evidence is mounting that the secretions of the cells are responsible for their therapeutic effects. These secretions include molecules and extracellular vesicles that have both local and distant effects. This review summarizes the up- and down-regulation of MSC anti-inflammatory, immune modulating, anti-tumor, and regenerative secretions resulting from different stimuli including: a) hypoxia, which increases the production of growth factors and anti-inflammatory molecules; b) pro-inflammatory stimuli that induce the secretion of immune modulating and anti-inflammatory factors; and c) 3 dimensional growth which up regulates the production of anti-cancer factors and anti-inflammatory molecules compared to monolayer culture. Finally we review in detail the most important factors present in conditioned medium of MSC that can be considered protagonists of MSC physiological effects including HGF, TGF-b, VEGF, TSG-6, PGE2 and galectins 1, and 9. We conclude that there is potential for the development of acellular therapeutic interventions for autoimmune, inflammatory, and malignant diseases and tissue regeneration from cellular secretions derived from MSCs cultured under the appropriate conditions.The mesenchymal stem cell (MSC) is being broadly studied in clinical trials. Contrary to the early paradigm of cell replacement and differentiation as a therapeutic mechanism of action, evidence is mounting that the secretions of the cells are responsible for their therapeutic effects. These secretions include molecules and extracellular vesicles that have both local and distant effects. This review summarizes the up- and down-regulation of MSC anti-inflammatory, immune modulating, anti-tumor, and regenerative secretions resulting from different stimuli including: a) hypoxia, which increases the production of growth factors and anti-inflammatory molecules; b) pro-inflammatory stimuli that induce the secretion of immune modulating and anti-inflammatory factors; and c) 3 dimensional growth which up regulates the production of anti-cancer factors and anti-inflammatory molecules compared to monolayer culture. Finally we review in detail the most important factors present in conditioned medium of MSC that can be considered protagonists of MSC physiological effects including HGF, TGF-b, VEGF, TSG-6, PGE2 and galectins 1, and 9. We conclude that there is potential for the development of acellular therapeutic interventions for autoimmune, inflammatory, and malignant diseases and tissue regeneration from cellular secretions derived from MSCs cultured under the appropriate conditions
Chemical and bioactive natural products from Microthyriaceae sp., an endophytic fungus from a tropical grass
Get PDFIn screening for natural products with antiparasitic activity, an endophytic fungus, strain F2611, isolated from above-ground tissue of the tropical grass Paspalum conjugatum (Poaceae) in Panama, was chosen for bioactive principle elucidation. Cultivation on malt extract agar (MEA) followed by bioassayguided chromatographic fractionation of the extract led to the isolation of the new polyketide integrasone B (1) and two known mycotoxins, sterigmatocystin (2) and secosterigmatocystin (3). Sterigmatocystin (2) was found to be the main antiparasitic compound in the fermentation extract of this fungus, possessing potent and selective antiparasitic activity against Trypanosoma cruzi, the cause of Chagas disease, with an IC50 value of 0 13 lmol l1 . Compounds 2 and 3 showed high cytotoxicity against Vero cells (IC50 of 0 06 and 0 97 lmol l1 , respectively). The new natural product integrasone B (1), which was co-purified from the active fractions, constitutes the second report of a natural product possessing an epoxyquinone with a lactone ring and exhibited no significant biological activity. Strain F2611 represents a previously undescribed taxon within the Microthyriaceae (Dothideomycetes, Ascomycota)In screening for natural products with antiparasitic activity, an endophytic fungus, strain F2611, isolated from above-ground tissue of the tropical grass Paspalum conjugatum (Poaceae) in Panama, was chosen for bioactive principle elucidation. Cultivation on malt extract agar (MEA) followed by bioassayguided chromatographic fractionation of the extract led to the isolation of the new polyketide integrasone B (1) and two known mycotoxins, sterigmatocystin (2) and secosterigmatocystin (3). Sterigmatocystin (2) was found to be the main antiparasitic compound in the fermentation extract of this fungus, possessing potent and selective antiparasitic activity against Trypanosoma cruzi, the cause of Chagas disease, with an IC50 value of 0 13 lmol l1 . Compounds 2 and 3 showed high cytotoxicity against Vero cells (IC50 of 0 06 and 0 97 lmol l1 , respectively). The new natural product integrasone B (1), which was co-purified from the active fractions, constitutes the second report of a natural product possessing an epoxyquinone with a lactone ring and exhibited no significant biological activity. Strain F2611 represents a previously undescribed taxon within the Microthyriaceae (Dothideomycetes, Ascomycota
A systematic account of the genus Plagiostoma (Gnomoniaceae, Diaporthales) based on morphology, host-associations, and a four-gene phylogeny
No full textMembers of the genus Plagiostoma inhabit leaves, stems, twigs, and branches of woody and herbaceous plants predominantly in the temperate Northern Hemisphere. An account of all known species of Plagiostoma including Cryptodiaporthe is presented based on analyses of morphological, cultural, and DNA sequence data. Multigene phylogenetic analyses of DNA sequences from four genes (β-tubulin, ITS, rpb2, and tef1-α) revealed eight previously undescribed phylogenetic species and an association between a clade composed of 11 species of Plagiostoma and the host family Salicaceae. In this paper these eight new species of Plagiostoma are described, four species are redescribed, and four new combinations are proposed. A key to the 25 accepted species of Plagiostoma based on host, shape, and size of perithecia, perithecial arrangement in the host, and microscopic characteristics of the asci and ascospores is provided. Disposition of additional names in Cryptodiaporthe and Plagiostoma is also discussedMembers of the genus Plagiostoma inhabit leaves, stems, twigs, and branches of woody and herbaceous plants predominantly in the temperate Northern Hemisphere. An account of all known species of Plagiostoma including Cryptodiaporthe is presented based on analyses of morphological, cultural, and DNA sequence data. Multigene phylogenetic analyses of DNA sequences from four genes (β-tubulin, ITS, rpb2, and tef1-α) revealed eight previously undescribed phylogenetic species and an association between a clade composed of 11 species of Plagiostoma and the host family Salicaceae. In this paper these eight new species of Plagiostoma are described, four species are redescribed, and four new combinations are proposed. A key to the 25 accepted species of Plagiostoma based on host, shape, and size of perithecia, perithecial arrangement in the host, and microscopic characteristics of the asci and ascospores is provided. Disposition of additional names in Cryptodiaporthe and Plagiostoma is also discusse