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Roselle (Hibiscus sabdariffa L.) is a crop of economic importance, refreshing drinks are prepared from its calyces, it is also attributed to antioxidant, antibacterial, and antihypertensive properties (Da-Costa-Rocha et al. 2014). In November 2022, in municipality of Iguala (18.355592N, 99.548546W, 749 m above sea level), Guerrero, México, roselle plants of approximately 1.5 months of age with basal rot were detected under greenhouse conditions. The symptoms consisted of wilting, yellowing, and root and stem rot with constriction in the base of the stem. The symptoms were detected in approximately 15% of plants at the operation. From symptomatic tissue, cuts were made into approximately 0.5 cm pieces, sterilized with 2% NaClO, washed with sterile distilled water, transferred to PDA medium amended with 50 mg/liter of Chloramphenicol, and incubated in the dark for four days at 28 °C. Rhizoctonia-like colonies were consistently obtained, and nine isolates were selected and purified by the hyphal-tip method. After four days, isolates developed a mycelium was light-white that became brown with age. Right-angled hyphal branching was also observed, in addition to a slight constriction at the base of the branches. In some older cultures, numerous dark brown sclerotia were observed. They were multinucleate cell with three to eight nuclei and measured from 1 to 2 mm in diameter. Together these characteristics were consistent with the description of Rhizoctonia solani Kühn (Parmeter 1970). The anastomosis group (AG) was confirmed by amplifying the ITS region with the primers ITS1 and ITS4 (White et al. 1990) of the RIJAM3 and RIJAM5 strains. The sequences were deposited in GenBank (Nos. OR364496 and OR364497 for RIJAM3 and RIJAM5, respectively). BLAST analysis, both isolates indicated 99.7 identity to R. solani AG-4 HG-I (GenBank: KM013470) strain ICMP 20043 (Ireland et al. 2015). The phylogenetic analysis of AGs sequences allowed assignment of isolates RIJAM3 and RIJAM5 to the AG-4 HG-1 clade. A pathogenicity test was performed on 20 one-month-old roselle plants. Mycelium of RIJAM3 isolate was inserted into the base of the stem with a sterile toothpick. As a control, a sterile toothpick with no mycelium was inserted in ten healthy plants. Additionally, 50 eight-day-old seedlings were inoculated by placing a 5-mm diameter agar plug colonized with mycelium of RIJAM3 at the base of the stem 10 mm below the soil surface. As control treatments, uncolonized PDA plugs were deposited at the base of 25 seedlings. The inoculated plants were incubated in a greenhouse with an average temperature and relative humidity of 28°C and 85%, respectively. Following inoculation, symptoms similar to those observed in the original outbreak were observed in plants after six days and only after four days in seedlings. In both experiments, the control plants and seedlings remained asymptomatic. R. solani was re-isolated from plants and seedlings, complying with Koch's postulates. The pathogenicity testing was repeated twice, with concordant results. In Nigeria and Malaysia R. solani was reported to seedling death to cause seedling dieback in roselle (Adeniji 1970; Eslaminejad and Zakaria 2011). In México R. solani AG-4 has been previously reported in crops of potato, chili and tomato (Montero-Tavera et al. 2013; Ortega-Acosta et al. 2022; Virgen-Calleros et al. 2000). To the best of our knowledge, this is the first report of R. solani AG-4 HG-I as a causing of root and basal stem rot on roselle in Mexico. This research provides information essential for informing the management of this disease, and may help design measures to prevent the spread of the pathogen to other regions.
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The guava (Psidium guajava L.) is a plant native to the tropical region of America. In Mexico, the area established with guava cultivation is 20,525 ha (SIAP 2021). Guava is commonly consumed as fresh fruit, being rich in nutrients such as vitamins and minerals (Murthy et al. 2020). During October 2020, in the municipality of Cocula (18.207835N, 99.670322W, 595 m above sea level), Guerrero, Mexico, severely infected immature guava fruits were observed. The incidence of disease in 150 sampled fruits was 12%. Were collected fifteen symptomatic fruits. The symptoms were circular to irregular dark brown spots that varied in size (0.5 to 2.5 cm). From symptomatic fruits, tissues were cut approximately 3 x 3 mm and disinfested with 1% NaOCl, washed three times with sterile distilled water, and transferred to PDA medium amended with streptomycin and tetracycline, and incubated at 28°C. Developing colonies were retransferred to new culture PDA medium, and purified by hyphal tip technique. Two representative isolates (PHYGUA7 and PHYGUA3) were selected for morphological and molecular characterization. After 15 days in PDA at 28°C in an incubator, colonies were flat, irregular, granular and greenish gray, pycnidia were black, granular, and grouped. The conidia were hyaline and ellipsoid, unicellular and smooth-walled, 7-11×5-6.5 µm (n=50), these characteristics were consistent with those described for the fungus Phyllosticta capitalensis (Wikee et al. 2013). Molecular identification was performed by partially sequencing the internal transcribed spacer gene (ITS), the actin gene (ACT), and the translation elongation factor 1-alpha (EF-1α) gene, using primers ITS1 and ITS4, ACT-512F/ ACT-783R, and EF1-728F/EF1-986R, respectively (White et al. 1990; Carbone and Kohn 1999). The resulting sequences were deposited in GenBank (PHYGUA7: OP810947, PHYGUA3: OP810948 for ITS, PHYGUA7: OP819845, PHYGUA3: OP819846 for ACT, and PHYGUA7: OP819847, PHYGUA3: OP819848 for EF-1α). Phylogenetic analysis using maximum likelihood concatenated sequences ITS, ACT and EF-1α with MEGA X, indicated that PHYGUA7 and PHYGUA3 isolated grouped with P. capitalensis (CPC 18848 type strain). For pathogenicity test of P. capitalensis, 15 healthy immature fruits in a field experiment in the fruits on the trees, and 15 healthy mature guava fruits (detached fruits) were superficially disinfected with 70% ethanol, wounded with a sterile toothpick, and inoculated at two equidistant points by inserting PHYGUA7 isolate mycelium. As a control treatment, 10 healthy immature fruits and 10 healthy mature fruits were only injured with a sterile toothpick. After 3 days symptoms were observed in mature fruits and numerous dark pycnidia developed, and seven days later symptoms were observed in immature fruits in all the points inoculated with the PHYGUA7 isolate, similar to the symptoms observed in the field. The control fruits remained asymptomatic. The fungus P. capitalensis was re-isolated from inoculated fruits, thus confirming Koch's postulates. In Mexico P. capitalensis has been reported in Mangifera indica, Epidendrum sp., and Schomburgkia tibicinis (Farr and Rossman, 2022). In Egypt and China P. capitalensis causes black spot on guava fruits (Arafat 2016; Liao et al. 2020). To our knowledge, this is the first report of P. capitalensis as the cause of brown spot on immature guava fruit in Mexico. This research provides relevant information to the design of disease management strategies.
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Pest outbreaks, harmful algal blooms and population collapses are extreme events with critical consequences for ecosystems. Therefore, understanding the ecological mechanisms underlying these extreme events is crucial. We evaluated theoretical predictions on the size scaling and variance of extreme population abundance by combining (i) the generalized extreme value (GEV) theory and (ii) the resource-limited metabolic restriction hypothesis for population abundance. Using the phytoplankton data from the L4 station in the English Channel, we showed a negative size scaling of the expected value of maximal density, whose confidence interval included the predicted metabolic scaling (α = -1) supporting theoretical predictions. The role of resources and temperature in the distribution of the size-abundance pattern and residuals was well characterized by the GEV distribution. This comprehensive modelling framework will allow to elucidate community structure and fluctuations and provide unbiased return times estimates, thereby improving the prediction accuracy of the timing of the population outbreaks.
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Ecossistema , Fitoplâncton , Densidade Demográfica , Tamanho Corporal , TemperaturaRESUMO
A recent paper by Beretta-Blanco and Carrasco-Letelier (2021) claims that agricultural eutrophication is not one of the main causes for cyanobacterial blooms in rivers and artificial reservoirs. By combining rivers of markedly different hydrological characteristics e.g., presence/absence and number of dams, river discharge and geological setting, the study speculates about the role of nutrients for modulating phytoplankton chlorophyll-a. Here, we identified serious flaws, from erratic and inaccurate data manipulation. The study did not define how erroneous original dataset values were treated, how the variables below the detection/quantification limit were numerically introduced, lack of mandatory variables for river studies such as flow and rainfall, arbitrary removal of pH > 7.5 values (which were not outliers), and finally how extreme values of other environmental variables were included. In addition, we identified conceptual and procedural mistakes such as biased construction/evaluation of model prediction capability. The study trained the model using pooled data from a short restricted lotic section of the (large) Uruguay River and from both lotic and reservoir domains of the Negro River, but then tested predictability within the (small) Cuareim River. Besides these methodological considerations, the article shows misinterpretations of the statistical correlation of cause and effect neglecting basic limnological knowledge of the ecology of harmful algal blooms (HABs) and international research on land use effects on freshwater quality. The argument that pH is a predictor variable for HABs neglects overwhelming basic paradigms of carbon fluxes and change in pH because of primary productivity. As a result, the article introduces the notion that HABs formation are not related to agricultural land use and water residence time and generate a great risk for the management of surface waterbodies. This reply also emphasizes the need for good practices of open data management, especially for public databases in view of external reproducibility.
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Negro ou Afro-Americano , Rios , Monitoramento Ambiental , Eutrofização , Proliferação Nociva de Algas , Humanos , Fósforo/análise , Reprodutibilidade dos Testes , UruguaiRESUMO
Microcystis aeruginosa complex (MAC) encompasses noxious colonial bloom forming cyanobacteria. MAC representatives bloom in eutrophic freshwater and brackish ecosystems with stagnant water, were temperature and salinity are the main variables modulating their distribution, biomass and toxicity. Cell abundance and biovolume of MAC colonies define regulatory standards for public health. These variables depend upon colony size that in turn changes with environmental conditions. Here, we conducted two series of experiments to evaluate the response of MAC colonies morphological traits (length, volume, mucilage and number of cells) to temperature and salinity. In two series of experiments in the laboratory, we exposed natural MAC communities to three different temperatures (10, 21 and 30 °C) and four salinity levels (0, 5, 10 and 25 ppt) typically found in estuaries. We found that average colony length, volume and mucilage thickness did not change with temperature, but the cell-free space inside the colonies was smaller at the highest evaluated temperature (30 °C). Salinity fostered an increase in colony length, volume and mucilage thickness, while cell-free space diminished, resulting in higher cell density. The number of cells per colony was significantly related to colony size (length and volume) and both, temperature and salinity, affected the parameters of the relationships. Based on present results we propose statistical models to predict cell number per colony based on length and volume and accounting for the effect of salinity and temperature on these traits. This is applicable to ecological studies and to the monitoring of estuarine aquatic environments, by means of a fast and more accurate estimation of cell numbers to define MAC toxic populations early warning systems. A protocol is suggested for its application while the analysis of the interaction of temperature and salinity, as well as the variability in natural environments are objectives for future researches.
Assuntos
Monitoramento Ambiental/métodos , Microcystis/fisiologia , Águas Salinas/química , Salinidade , Temperatura , Microbiologia da ÁguaRESUMO
The Microcystis aeruginosa complex (MAC) clusters many of the most common freshwater and brackish bloom-forming cyanobacteria. In monitoring protocols, biovolume estimation is a common approach to determine MAC colonies biomass and useful for prediction purposes. Biovolume (µm3 mL-1) is calculated multiplying organism abundance (orgL-1) by colonial volume (µm3org-1). Colonial volume is estimated based on geometric shapes and requires accurate measurements of dimensions using optical microscopy. A trade-off between easy-to-measure but low-accuracy simple shapes (e.g. sphere) and time costly but high-accuracy complex shapes (e.g. ellipsoid) volume estimation is posed. Overestimations effects in ecological studies and management decisions associated to harmful blooms are significant due to the large sizes of MAC colonies. In this work, we aimed to increase the precision of MAC biovolume estimations by developing a statistical model based on two easy-to-measure dimensions. We analyzed field data from a wide environmental gradient (800â¯km) spanning freshwater to estuarine and seawater. We measured length, width and depth from ca. 5700 colonies under an inverted microscope and estimated colonial volume using three different recommended geometrical shapes (sphere, prolate spheroid and ellipsoid). Because of the non-spherical shape of MAC the ellipsoid resulted in the most accurate approximation, whereas the sphere overestimated colonial volume (3-80) especially for large colonies (MLD higher than 300⯵m). Ellipsoid requires measuring three dimensions and is time-consuming. Therefore, we constructed different statistical models to predict organisms depth based on length and width. Splitting the data into training (2/3) and test (1/3) sets, all models resulted in low training (1.41-1.44%) and testing average error (1.3-2.0%). The models were also evaluated using three other independent datasets. The multiple linear model was finally selected to calculate MAC volume as an ellipsoid based on length and width. This work contributes to achieve a better estimation of MAC volume applicable to monitoring programs as well as to ecological research.
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Monitoramento Ambiental/métodos , Microcystis/citologia , Microcystis/crescimento & desenvolvimento , Biomassa , Água Doce/microbiologia , Modelos Lineares , Água do Mar/microbiologia , UruguaiRESUMO
BACKGROUND: Sorafenib is a standard treatment for patients (pts) with advanced hepatocellular carcinoma (aHCC), although the clinical benefit is heterogeneous between different pts groups. Among novel prognostic factors, a low baseline neutrophil-to-lymphocyte ratio (bNLR) and early-onset diarrhoea have been linked with a better prognosis. PURPOSE: To identify prognostic factors in pts with aHCC treated with 1st-line sorafenib and to develop a new prognostic score to guide management. MATERIALS AND METHODS: Retrospective review of 145 pts bNLR, overall toxicity, early toxicity rates and overall survival (OS) were assessed. Univariate and multivariate analysis of prognostic factors for OS was performed. The prognostic score was calculated from the coefficients found in the Cox analysis. ROC curves and pseudoR2 index were used for internal validation. Discrimination ability and calibration were tested by Harrel's c-index (HCI) and Akaike criteria (AIC). RESULTS: The optimal bNLR cut-off for the prediction of OS was 4 (AUC 0.62). Independent prognostic factors in multivariate analysis for OS were performance status (PS) (p < .0001), Child-Pugh (C-P) score (p = 0.005), early-onset diarrhoea (p = 0.006) and BNLR (0.011). The prognostic score based on these four variables was found efficient (HCI = 0.659; AIC = 1.180). Four risk groups for OS could be identified: a very low-risk (median OS = 48.6 months), a low-risk (median OS = 11.6 months), an intermediate-risk (median OS = 8.3 months) and a high-risk group (median OS = 4.4 months). CONCLUSIONS: PS and C-P score were the main prognostic factors for OS, followed by early-onset diarrhoea and bNLR. We identified four risk groups for OS depending on these parameters. This prognostic model could be useful for patient stratification, but an external validation is needed.
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Antineoplásicos/uso terapêutico , Carcinoma Hepatocelular/tratamento farmacológico , Inflamação/patologia , Neoplasias Hepáticas/tratamento farmacológico , Niacinamida/análogos & derivados , Compostos de Fenilureia/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Área Sob a Curva , Carcinoma Hepatocelular/patologia , Diarreia/induzido quimicamente , Diarreia/epidemiologia , Feminino , Humanos , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/patologia , Contagem de Linfócitos , Masculino , Pessoa de Meia-Idade , Neutrófilos , Niacinamida/uso terapêutico , Prognóstico , Modelos de Riscos Proporcionais , Curva ROC , Estudos Retrospectivos , Índice de Gravidade de Doença , Sorafenibe , Resultado do TratamentoRESUMO
RESUMEN La carne de cerdo se considera fuente de alto valor nutritivo por su alto contenido de proteína; sin embargo, su transporte representa un eslabón crítico, por cuanto genera pérdidas económicas, cuando se producen alteraciones en el bienestar animal que repercuten en los parámetros nutricionales, disminuyen la capacidad de retención de agua y ocasionan pérdidas de proteína. El objetivo de este estudio fue relacionar las características de los transportes con las características nutricionales de la carne porcina destinada a consumo humano en el Valle de Aburrá (Antioquia, Colombia) en 2017. Se visitaron tres plantas de sacrificio del Valle de Aburrá con muestreo probabilístico estratificado por planta y afijación igual, obteniendo información de 338 animales. Se analizaron los parámetros nutricionales de las muestras cárnicas, así como variables sociodemográficas, de infraestructura, bienestar animal y prácticas de conducción de los transportistas. Se realizaron pruebas de ji-cuadrado (χ 2) para variables cualitativas dicotómicas, regresión logística para variables cualitativas politómicas y U de Mann-Whitney para variables cuantitativas. Se encontró asociación entre varios de los parámetros indagados con valores p estadísticamente significativos (p = 0,000; así, no tener suministro de agua permanente para los animales incrementa en 46,55 veces (IC 18,08 - 120,07) la posibilidad de presentar carnes nutricionalmente inadecuadas. Se concluye que factores como la falta de suministro de agua a los cerdos, el mal estado de pisos y separadores, la deficiente capacitación de los transportistas, la falta de supervisión a los animales, no tener el certificado técnico-mecánico y la velocidad promedio de 80 km/h, se asocian con la generación de productos cárnicos nutricionalmente inadecuados.
ABTRACT Pork meat is considered a source of high nutritional value due to its high protein content, however, transport is a critical link to generate economic losses by producing alterations in animal welfare, which have an impact on nutritional parameters, decreasing the capacity of water retention, and generating protein losses. The objective of this study was to relate the characteristics of transport, with the nutritional characteristics of pork for human consumption in the Valle de Aburrá (Antioquia, Colombia) in 2017. In this location, three slaughterhouses were visited with probabilistic sampling stratified by plant and equal affixation, obtaining information from 338 animals. The nutritional parameters of the meat samples and sociodemographic variables, infrastructure, animal welfare and driving practices of the transporters were analyzed. ji-square (χ 2) tests were performed for dichotomous qualitative variables, logistic regression for qualitative polytomous variables and Mann-Whitney U test for quantitative variables. An association was found between several of the parameters investigated with statistically significant p values (p = 0,000), where, having no permanent water supply for the animals increases in 46.55 times (IC 18.08 - 120.07) the possibility of presenting nutritionally inadequate meats. It was concluded that factors such as lack of water supply to pigs, poor condition of the floors and separators, lack of training in transporters, lack of supervision of animals, lack of mechanical technical certification and average speed of 80 km/h are associated with the generation of nutritionally inadequate meat products.
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Determining statistical patterns irrespective of interacting agents (i.e. macroecology) is useful to explore the mechanisms driving population fluctuations and extinctions in natural food webs. Here, we tested four predictions of a neutral model on the distribution of community fluctuations (CF) and the distributions of persistence times (APT). Novel predictions for the food web were generated by combining (1) body size-density scaling, (2) Taylor's law and (3) low efficiency of trophic transference. Predictions were evaluated on an exceptional data set of plankton with 15 years of weekly samples encompassing c. 250 planktonic species from three trophic levels, sampled in the western English Channel. Highly symmetric non-Gaussian distributions of CF support zero-sum dynamics. Variability in CF decreased while a change from an exponential to a power law distribution of APT from basal to upper trophic positions was detected. Results suggest a predictable but profound effect of trophic position on fluctuations and extinction in natural communities.
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Extinção Biológica , Cadeia Alimentar , Plâncton/fisiologia , Inglaterra , Modelos Biológicos , Oceanos e Mares , Dinâmica PopulacionalRESUMO
The amount of biomass production per unit of food consumed (P/Q) represents an important quantity in ecosystem functioning, because it indicates how efficient a population transforms ingested food into biomass. Several investigations have noticed that P/Q remains relatively constant (or invariant) across fish population that feed at the same food-type level (carnivorous/herbivorous). Nevertheless, theoretical explanation for this invariant is still lacking. In this paper, we demonstrate that P/Q remains invariant across fish populations with stable-age distribution. Three key assumptions underpin the P/Q invariant: (1) the ratio between natural mortality M and von Bertalanffy growth parameter k (M/k ratio) should remain invariant across fish populations; (2) a parameter defining the fraction of ingested food available for growth needs to remain constant across fish that feed at the same trophic level; (3) third, the ratio between length at age 0 ([Formula: see text]) and asymptotic length ([Formula: see text]) should be constant across fish populations. The influence of these assumptions on the P/Q estimates were numerically assessed considering fish populations of different lifespan. Numerical evaluations show that the most critical condition highly relates to the first assumption, M/k. Results are discussed in the context of the reliability of the required assumption to consider the P/Q invariant in stable-age distributed fish populations.
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Biomassa , Comportamento Alimentar , Peixes/fisiologia , Animais , Comportamento Animal , Ecossistema , Modelos Lineares , Modelos Biológicos , Reprodutibilidade dos Testes , Especificidade da EspécieRESUMO
Snakebite envenoming is an important problem in the livestock industry in Costa Rica. Of the 22 species of venomous snakes in the country, Bothrops asper is involved in most animal envenomings. Envenomation is typically characterised by swelling and bleeding at the bite site, coagulopathy, systemic haemorrhage, and, in some cases, death. The aims of the present study were to describe the clinical manifestations of B. asper envenomation in cattle and to evaluate the treatment efficacy of antivenom administration. The clinical effects of naturally occurring envenomation were reproduced experimentally in cattle by giving an intramuscular injection of either 10 mg or 50 mg venom to replicate mild and severe envenomings, respectively. Intravenous antivenom given 6 h after experimental venom injection controlled the symptoms; a dose of 120 mL was found to be appropriate for moderate and 200 mL for severe naturally occurring envenomings. Although administration of antivenom within the first 6 h following a snakebite prevented systemic effects, it did not reduce the extent of swelling at the bite site. Delayed administration of antivenom was not effective in saving naturally envenomed animals. The results indicate that, when promptly administered, antivenom constitutes an effective treatment for B. asper snakebite envenomation in cattle.
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Antivenenos/uso terapêutico , Bothrops , Doenças dos Bovinos/tratamento farmacológico , Mordeduras de Serpentes/veterinária , Animais , Antivenenos/efeitos adversos , Antivenenos/sangue , Bovinos , Doenças dos Bovinos/etiologia , Costa Rica , Venenos de Crotalídeos , Mordeduras de Serpentes/fisiopatologiaRESUMO
BACKGROUND AND OBJECTIVES: Instituto Clodomiro Picado has developed an immunoglobulin G (IgG) plasma fractionation process combining a polyethylene glycol/phosphate aqueous two-phase system (ATPS), caprylic acid precipitation and anion-exchange membrane chromatography. We evaluated the purity and in vitro thrombogenicity of such IgG, in line with current international requirements. MATERIALS AND METHODS: Contributions of the different production steps to reduce thrombogenicity were assessed at 0·2 l-scale, and then the methodology was scaled-up to a 10 l-scale and final products (n = 3) were analysed. Purity, immunoglobulin composition, and subclass distribution were determined by electrophoretic and immunochemical methods. The in vitro thrombogenic potential was determined by a thrombin generation assay (TGA) using a Technothrombin fluorogenic substrate. Prekallikrein activator (PKA), plasmin, factor Xa, thrombin and thrombin-like activities were assessed using S-2302, S-2251, S-2222, S-2238 and S-2288 chromogenic substrates, respectively, and FXI by an ELISA. RESULTS: The thrombogenicity markers were reduced mostly during the ATPS step and were found to segregate mostly into the discarded liquid upper phase. The caprylic acid precipitation eliminated the residual procoagulant activity. The IgG preparations made from the 10 l-batches contained 100% gamma proteins, low residual IgA and undetectable IgM. The IgG subclass distribution was not substantially affected by the process. TGA and amidolytic activities revealed an undetectable in vitro thrombogenic risk and the absence of proteolytic enzymes in the final product. CONCLUSIONS: Fractionating human plasma by an ATPS combined with caprylic acid and membrane chromatography resulted in an IgG preparation of high purity and free of a detectable in vitro thrombogenic risk.
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Fracionamento Químico/métodos , Cromatografia/métodos , Imunoglobulina G/isolamento & purificação , Plasma/química , Caprilatos/química , Ensaio de Imunoadsorção Enzimática , Fator XIIa/análise , Humanos , Imunoglobulina G/química , Oligopeptídeos/química , Trombina/biossínteseRESUMO
Understanding the mechanisms that maintain biodiversity is a fundamental problem in ecology. Competition is thought to reduce diversity, but hundreds of microbial aquatic primary producers species coexist and compete for a few essential resources (e.g., nutrients and light). Here, we show that resource competition is a plausible mechanism for explaining clumpy distribution on individual species volume (a proxy for the niche) of estuarine phytoplankton communities ranging from North America to South America and Europe, supporting the Emergent Neutrality hypothesis. Furthermore, such a clumpy distribution was also observed throughout the Holocene in diatoms from a sediment core. A Lotka-Volterra competition model predicted position in the niche axis and functional affiliation of dominant species within and among clumps. Results support the coexistence of functionally equivalent species in ecosystems and indicate that resource competition may be a key process to shape the size structure of estuarine phytoplankton, which in turn drives ecosystem functioning.
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Biodiversidade , Biomassa , Ecossistema , Fitoplâncton/fisiologia , Diatomáceas , Ecologia , Estuários , Modelos BiológicosRESUMO
In December 2011, edible sunflower sprouts (Helianthus annus) of two different commercially grown cultivars (Sungrown and Tiensvold) exhibiting stem and cotyledon lesions were submitted to the New Mexico State University Plant Clinic for disease diagnosis. The sample originated from an organic farm in Santa Fe County where the grower utilizes a small indoor growing facility. Stem lesions were elongate, reddish brown, and often constricted, resulting in stem girdling. Lesions on the cotyledons were dark brown with tan centers and round to irregular in shape. In some cases, the entire cotyledon was blighted. Fungal hyphae were observed on some lesions using a dissecting microscope. Colletotrichum acutatum was isolated from stem and cotyledon lesions when symptomatic tissue was plated on water agar. Conidia were fusiform ranging from 6.4 to 18.4 µm long and 2.1 to 5.1 µm wide and averaged 11.9 µm × 3.4 µm. Spores were measured from cream-colored colonies produced on acidified potato dextrose agar. PCR amplification and sequence analysis of 5.8S ribosomal DNA and internal transcribed spacers I and II was performed using primers ITS4 and ITS6 (2). An amplification product of approximately 600 base pairs in size was directly sequenced (GenBank Accession No. JX444690). A BLAST search of the NCBI total nucleotide collection revealed a 99% identity to multiple C. acutatum (syn: C. simmondsii) isolates. Four isolates were identified as C. acutatum based on morphological characteristics and DNA analysis. Koch's postulates were performed using four isolates of the pathogen and the two commercial sunflower cultivars (Sungrown and Tiensvold) originally submitted for disease analysis. Sunflower seeds were imbibed in distilled water for 24 h then sewn into peat plugs. Prior to seed germination, 5 ml of a C. acutatum spore solution (1 × 106/ml) from each isolate was applied to five peat plugs using an atomizer. Control plants were inoculated with distilled water and otherwise treated identically. Both sunflower cultivars were inoculated with each isolate of the pathogen and the test was replicated twice. The sewn peat plugs were incubated for 5 days at 21°C and 50% relative humidity. Symptoms similar to the original samples were present on 100% of the sprouts after 5 days. PCR and sequence analysis performed on cultures obtained from lesions showed a 100% match to the original New Mexico isolates fulfilling Koch's postulates. In an indoor organic facility, such as the one in NM, this disease has the potential to be very difficult to manage and the potential to infect a high percentage of the crop resulting in significant economic losses. To our knowledge, this is the second report of C. acutatum on sunflower sprouts in the United States (1) and the first report in New Mexico. References: (1) S. T. Koike et al. Plant Dis. 93:1351, 2009. (2) T. J. White et al. Page 315 in: PCR Protocols: A Guide to Methods and Applications. M. A. Innis et al., eds. Academic Press, San Diego, 1990.
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Species of the genus Bothrops induce the vast majority of snakebite envenomings in Latin America. A preclinical study was performed in the context of a regional network of public laboratories involved in the production, quality control and development of antivenoms in Latin America. The ability of seven polyspecific antivenoms, produced in Argentina, Brazil, Peru, Bolivia, Colombia and Costa Rica, to neutralize lethal, hemorrhagic, coagulant, defibrinogenating and myotoxic activities of the venoms of Bothrops neuwiedi (diporus) (Argentina), Bothrops jararaca (Brazil), B. neuwiedi (mattogrossensis) (Bolivia), Bothrops atrox (Peru and Colombia) and Bothrops asper (Costa Rica) was assessed using standard laboratory tests. Despite differences in the venom mixtures used in the immunization of animals for the production of these antivenoms, a pattern of extensive cross-neutralization was observed between these antivenoms and all the venoms tested, with quantitative differences in the values of effective doses. This study reveals the capacity of these antivenoms to neutralize, in preclinical tests, homologous and heterologous Bothrops venoms in Central and South America, and also highlight quantitative differences in the values of Median Effective Doses (ED50s) between the various antivenoms.
Assuntos
Antivenenos/imunologia , Bothrops/fisiologia , Venenos de Crotalídeos/imunologia , Fatores Imunológicos/imunologia , Testes de Neutralização/métodos , Animais , Coagulação Sanguínea/efeitos dos fármacos , Creatina Quinase/sangue , Venenos de Crotalídeos/efeitos adversos , Avaliação Pré-Clínica de Medicamentos , Feminino , Fibrinólise/efeitos dos fármacos , Hemorragia/induzido quimicamente , América Latina , Dose Letal Mediana , Masculino , Camundongos , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/enzimologia , Miosite/induzido quimicamenteRESUMO
The relative proportion of the circulating luteinizing hormone isoforms in goats during follicular phase (pre-ovulatory peak; F) and anestrus (A) was investigated. Estrus was synchronized in six goats with a prostaglandin analogue. After estrus was detected, blood samples were taken at 1 h intervals for 24 h. Four anestrous goats received 100 microg i.v. of GnRH and blood samples were collected every 15 min for 5 h. Samples with the greatest LH concentration in follicular phase and after GnRH administration (anestrus) were analyzed by chromatofocusing and eluted with a pH gradient from 10.5 to 3.5. For quantification purposes eluted LH was grouped into basic (pH> or =7.5), neutral (pH 7.4-6.5) and acidic isoforms (pH< or =6.4) as well as by pH unit. In both physiological conditions (PC), basic and acidic isoforms were greater than the neutral. With this grouping criteria, there was an interaction between PC and pH group, with the proportion of neutral isoforms being greater (p<0.05) in A (12.0+/-0.8%) as compared with F (5+/-2%). Analysis by pH unit showed a very basic group of eluted isoforms (pH> or =10), which amounted to a percentage of 6.0+/-0.4% of the total observed during A, and 3+/-1% during F (p<0.05). Predominant isoforms in A eluted in the pH range 9.99-9.0 (42+/-3%) as compared to 7+/-3% (p<0.01) in that pH range in F. In contrast, the predominant isoforms in F eluted in the pH range 8.99-8.0, representing 55+/-8%, while in A the proportion was 11+/-2% (p<0.01). Isoforms eluted at the pH range 7.9-7 represented a significantly greater proportion during A (5.0+/-0.6%) as compared with F (3+/-1%). This is the first report on goat LH circulating isoforms. During A the LH isoforms secreted by the pituitary are more basic than during F.
Assuntos
Anestro/metabolismo , Fase Folicular/metabolismo , Cabras/fisiologia , Hormônio Luteinizante/química , Hormônio Luteinizante/metabolismo , Anestro/efeitos dos fármacos , Animais , Feminino , Fase Folicular/efeitos dos fármacos , Hormônio Liberador de Gonadotropina/farmacologia , Isoformas de Proteínas/química , Isoformas de Proteínas/metabolismoRESUMO
This paper intends to compare quality of life and its relationships with depressive symptomatology in alcoholic patients. We selected two groups the first, patients assisting a recovery center for alcoholics, and the second, patients that had attended this center in the past. Both groups received the SF-36 and the Beck Depression Inventory. Comparing the results from both groups, we could not find a significant direct relationship between patients appreciation about quality of life, measured by SF-36, and presence of depression, measured in the Beck Inventory.
El objetivo del presente estudio es comprar el nivel de calidad de vida y su vinculación con la sintomatología depresiva en sujetos alcohólicos. Para estos fines se han considerado dos muestras de sujetos, aquellos que están en tratamiento en un club de recuperados alcohólicos en el momento del estudio y aquellos que han pertenecido a esta institución y se encontraban en sus hogares sin asistir a las actividades de este centro. Ambas muestras se aplicaron los instrumentos de evaluación de calidad de vida (SF-36) y de presencia de síntomas depresivos (Inventario de Depresión de Beck). Al comparar ambos grupos y al efectuar las pruebas estadísticas, no se logró establecer una directa relación entre las apreciaciones acerca de la calidad de vida y la presencia de síntomas depresivos en el conjunto de la población estudiada.
Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Idoso de 80 Anos ou mais , Alcoolismo , Qualidade de Vida , DepressãoRESUMO
Se diseñó un estudio de Farmacovigilancia (FVG), centrado en tres Hospitales Públicos de Córdoba, buscando detectar Reacciones Adversas por medicamentos. A tal fin se realizaron cursos formadores de recursos humanos en FVG. Se distribuyeron fichas de FVG., de diseño propio, recuperadas luego. Para cálculo estadístico se aplicó el INFO 4. Se recuperaron 84 fichas informadas Los grupos de medicamentos involucrados: fueron: Antibióticos (22%), cardiovasculares (16%), antiulcerosos (10%), ansiolíticos (8.75%), AINEs (8%), oncológicos (6%), anticonvulsivantes (3.75%), hipolipemiantes (3.5%), hormonas sexuales (2.5%), hipoglucemiantes (2.5%), expansores plasmáticos (2.5%). Los órganos afectados por RAM fueron: SNC (25%), piel (25%), gastrointestinal (17.5%), Sangre (7.5%), cardiovascular (7.5%), respiratorio (7%), inmunes (6%), renal (4%). El análisis de imputabilidad indicó: RAM Definidas: 10% - RAM Probables: 90%.(AU)
There were designed Monitorings study (FVG), centred on three Public Hospitals of C6rdoba, seeking to detect Adverse Reactions for medicines. To such purpose there were realized forming courses of human resources in FVG. FVGs cards were distributed, of own design, recovered then. For statistical calculation there was applied the INFO 4. 84 informed cards were recovered. The groups of involved medicines: they were: Antibiotics (22%), cardiovascular (16%), antiulcerous (10%), anxiolytics (8.75%), nonsteroidal anti-inflammatory (8%), onchologics (6%), anticonvulsants (3.75%), hypolypemics (3.5%), sexual hormones (2.5%), hypoglycemics (2.5%), plasmatic expansors (2.5%). The organs affected by RAM were: Central Nervous System (25%), skin (25%), gastrointestinal (17.5%), Bleeds (7.5%), cardiovascular (7.5%), respiratory (7%), immune (6%), renal (4%). The analysis of imputability indicated: Definite RAM: 10 % Probable RAM: 90%.(AU)
Assuntos
Humanos , Monitoramento de Medicamentos , Preparações Farmacêuticas/efeitos adversos , Sistemas de Notificação de Reações Adversas a Medicamentos , ArgentinaRESUMO
Se diseñó un estudio de Farmacovigilancia (FVG), centrado en tres Hospitales Públicos de Córdoba, buscando detectar Reacciones Adversas por medicamentos. A tal fin se realizaron cursos formadores de recursos humanos en FVG. Se distribuyeron fichas de FVG., de diseño propio, recuperadas luego. Para cálculo estadístico se aplicó el INFO 4. Se recuperaron 84 fichas informadas Los grupos de medicamentos involucrados: fueron: Antibióticos (22%), cardiovasculares (16%), antiulcerosos (10%), ansiolíticos (8.75%), AINEs (8%), oncológicos (6%), anticonvulsivantes (3.75%), hipolipemiantes (3.5%), hormonas sexuales (2.5%), hipoglucemiantes (2.5%), expansores plasmáticos (2.5%). Los órganos afectados por RAM fueron: SNC (25%), piel (25%), gastrointestinal (17.5%), Sangre (7.5%), cardiovascular (7.5%), respiratorio (7%), inmunes (6%), renal (4%). El análisis de imputabilidad indicó: RAM Definidas: 10% - RAM Probables: 90%.
There were designed Monitorings study (FVG), centred on three Public Hospitals of C6rdoba, seeking to detect Adverse Reactions for medicines. To such purpose there were realized forming courses of human resources in FVG. FVG's cards were distributed, of own design, recovered then. For statistical calculation there was applied the INFO 4. 84 informed cards were recovered. The groups of involved medicines: they were: Antibiotics (22%), cardiovascular (16%), antiulcerous (10%), anxiolytics (8.75%), nonsteroidal anti-inflammatory (8%), onchologics (6%), anticonvulsants (3.75%), hypolypemics (3.5%), sexual hormones (2.5%), hypoglycemics (2.5%), plasmatic expansors (2.5%). The organs affected by RAM were: Central Nervous System (25%), skin (25%), gastrointestinal (17.5%), Bleeds (7.5%), cardiovascular (7.5%), respiratory (7%), immune (6%), renal (4%). The analysis of imputability indicated: Definite RAM: 10 % Probable RAM: 90%.
Assuntos
Humanos , Monitoramento de Medicamentos , Preparações Farmacêuticas/efeitos adversos , Sistemas de Notificação de Reações Adversas a Medicamentos , ArgentinaRESUMO
PROTEKT (Prospective Resistant Organism Tracking and Epidemiology for the Ketolide Telithromycin) is a global surveillance study established in 1999 to monitor antibacterial resistance of respiratory tract organisms. Thirteen centers from Argentina, Brazil and Mexico participated during 1999-2000; they collected 1806 isolates (Streptococcus pneumoniae 518, Haemophilus influenzae 520, Moraxella catarrhalis 140, Staphylococcus aureus 351, S. pyogenes 277). Overall, 218 (42.1%) of the S. pneumoniae isolates had reduced susceptibility to penicillin, 79 (15.3%) were penicillin-resistant and 79 (15.3%) were erythromycin-resistant. Mexico had the highest prevalence of penicillin (76.5%) and erythromycin (31.2%) resistance. Of 77 erythromycin-resistant S. pneumoniae tested for resistance genotype, 43 possessed mef(A), 33 possessed erm(B) and 1 possessed both erm(B) and mef(A) mechanism. All S. pneumoniae isolates were fully susceptible to telithromycin, linezolid, teicoplanin and vancomycin. Among H. influenzae isolates, 88 (16.9%) produced beta-lactamase, ranging from 11% (Brazil) to 24.5% (Mexico). Among M. catarrhalis isolates, 138 (98.6%) produced beta-lactamase. Twenty-four (8.7%) of the S. pyogenes isolates were erythromycin-resistant; resistance being attributable to mefA (n=18), ermTR (n=5) and ermB (n=1). All H. influenzae, M. catarrhalis and S. pyogenes were fully susceptible to telithromycin. Methicillin resistance was found in 26.5% of the S. aureus isolates (Argentina 15%; Mexico 20%; Brazil 31.3%). Telithromycin was effective against 97.7% of methicillin-susceptible isolates. PROTEKT confirms that antibacterial resistance is an emerging problem in Latin America. The previously reported high levels of pneumococcal resistance to the beta-lactam and macrolides were exceeded. New agents that do not induce resistance or that exert low selective pressure, e.g. telithromycin, are essential to safeguard future antibacterial efficacy.