ABSTRACT
Twenty-five years ago, a seminal paper demonstrated that warm temperatures increase auxin levels to promote hypocotyl growth in Arabidopsis thaliana. Here we highlight recent advances in auxin-mediated thermomorphogenesis and identify unanswered questions. In the warmth, PHYTOCHROME INTERACTING FACTOR 4 (PIF4) and PIF7 bind the YUCCA8 gene promoter and, in concert with histone modifications, enhance its expression to increase auxin synthesis in the cotyledons. Once transported to the hypocotyl, auxin promotes cell elongation. The meta-analysis of expression of auxin-related genes in seedlings exposed to temperatures ranging from cold to hot shows complex patterns of response. Changes in auxin only partially account for these responses. The expression of many SMALL AUXIN UP RNA (SAUR) genes reaches a maximum in the warmth, decreasing towards both temperature extremes in correlation with the rate of hypocotyl growth. Warm temperatures enhance primary root growth, the response requires auxin, and the hormone levels increase in the root tip but the impacts on cell division and cell expansion are not clear. A deeper understanding of auxin-mediated temperature control of plant architecture is necessary to face the challenge of global warming.
Subject(s)
Arabidopsis Proteins , Arabidopsis , Arabidopsis Proteins/genetics , Arabidopsis Proteins/metabolism , Indoleacetic Acids/metabolism , Temperature , Arabidopsis/metabolism , Hypocotyl , Gene Expression , Gene Expression Regulation, Plant , Basic Helix-Loop-Helix Transcription Factors/metabolism , DNA-Binding Proteins/geneticsABSTRACT
Tocochromanols constitute the different forms of vitamin E (VTE), essential components of the human diet, and display a high membrane protectant activity. By combining interval mapping and genome-wide association studies (GWAS), we unveiled the genetic determinants of tocochromanol accumulation in tomato (Solanum lycopersicum) fruits. To enhance the nutritional value of this highly consumed vegetable, we dissected the natural intraspecific variability of tocochromanols in tomato fruits and genetically engineered their biosynthetic pathway. These analyses allowed the identification of a total of 25 quantitative trait loci interspersed across the genome pinpointing the chorismate-tyrosine pathway as a regulatory hub controlling the supply of the aromatic head group for tocochromanol biosynthesis. To validate the link between the chorismate-tyrosine pathway and VTE, we engineered tomato plants to bypass the pathway at the arogenate branch point. Transgenic tomatoes showed moderate increments in tocopherols (up to approximately 20%) and a massive accumulation of tocotrienols (up to approximately 3400%). Gene expression analyses of these plants reveal a trade-off between VTE and natural variation in chorismate metabolism explained by transcriptional reprogramming of specific structural genes of the pathway. By restoring the accumulation of alpha-tocotrienols (α-t3) in fruits, the plants produced here are of high pharmacological and nutritional interest.
Subject(s)
Chorismic Acid/metabolism , Solanum lycopersicum/metabolism , Vitamin E/analysis , Chromosome Mapping , Fruit/chemistry , Fruit/metabolism , Genes, Plant/genetics , Genetic Engineering , Genetic Loci , Genetic Variation , Genome-Wide Association Study , Solanum lycopersicum/chemistry , Solanum lycopersicum/genetics , Metabolic Networks and Pathways/genetics , Plants, Genetically Modified , Polymorphism, Single Nucleotide , Quantitative Trait, Heritable , Tyrosine/metabolism , Vitamin E/metabolismABSTRACT
En la intención de continuar explorando la utilización de las técnicas proyectivas gráficas de diagnóstico en la detección y comprensión de la organización psíquica del sujeto con trastornos somáticos, se implementa el Test "Dos Personas", originalmente creado para evaluar el vínculo de pareja internalizado. Por la estructura de la técnica (gráficoverbal) ponemos, ahora, a prueba su aplicación para la captación de las particularidades de la imagen corporal y de la mentalización, aspectos decisivos en la organización psíquica del sujeto vulnerable somático. Se presentan los resultados obtenidos en 100 sujetos de 25 a 35 años con afecciones somáticas. Con un diseño exploratorio descriptivo se investigan las características del grafismo y del relato de estos sujetos, comparándolos con un grupo equivalente sin afecciones somáticas. Se siguió una metodología cualicuantitativa en función de categorías de análisis predeterminadas relevantes en la metapsicología psicosomática. Se arriba a resultados concordantes con la teoría psicosomática psicodinámica.(AU)
In order to continue exploring the use of projective graphic diagnostic techniques in the detection and understanding of the psychic organization in individuals with somatic disorders, the present study looks into the application of the "Two Persons" Test, originally created to evaluate the internalized couple bond. Taking into account the structure of the technique (graphicverbal) this investigation now tests the applicability of the test to capture particularities of body image and mentalization, decisive aspects in the vulnerable psychic organization of somatic individuals. Results were obtained from a sample of 100 individuals aged 25 to 35 years old with somatic afflictions. A descriptive exploratory design is applied to investigate the characteristics of the graphics and the narrative of these individuals, comparing them with those of an equivalent group without somatic afflictions. A qualitative quantitative methodology was privileged in accordance with predetermined categories of analysis relevant in psychosomatic metapsychology. The results are consistent with the psychodynamic psychosomatic theory.(AU)
Subject(s)
Adult , Projective Techniques , Psychology , Psychophysiologic DisordersABSTRACT
En Enterococcus spp. aislados de quesos de oveja se investigó la resistencia in vitro a antimicrobianos de utilización clínica. Se determinó la concentración inhibitoria mínima (CIM) para gentamicina, estreptomicina, vancomicina, teicoplanina, ampicilina, imipenem, linezolid y tigeciclina. Se detectó la producción de β-lactamasa y se realizaron experimentos de conjugación para transferir resistencia a gentamicina. En un aislamiento de E. faecalis y en 10 de E. faecium se observó resistencia a ampicilina; se demostró la producción de β-lactamasa en un E. faecalis. En E. faecium, 15 aislamientos fueron resistentes a imipenem; 4 a linezolid y 5 a glucopéptidos. En 4 aislamientos de E. faecalis se demostró alto nivel de resistencia plasmídica a gentamicina. No se observaron aislamientos resistentes a tigeciclina. El queso de oveja es un reservorio de enterococos resistentes con potencial diseminación al hombre a través de la cadena alimentaria.
In vitro resistance to clinically used antimicrobials was investigated in Enterococcus spp. isolated from goat cheese. The gentamycin, streptomycin, vancomycin, teicoplanin, ampicillin, imipenem, linezolid and tigecyclin minimum inhibitory concentration (MIC) was determined. Β-lactamase production was detected and conjugation experiments were carried out for transferring gentamycin resistance. In one E. faecalis and in 10 E. faecium isolates there was ampicillin resistance and β-lactamase production was demonstrated in one E. faecalis. Fifteen E. faecalis were imipenenem resistant; 4 linezolid resistant and 5 glucopeptide resistant. There was a high level of plasmidic resistance to tigecyclin in 4 E. faecalis isolates. There were no tigecyclin resistant isolates. Goat cheese is a reservoir of resistant enterococci with potencial human dissemination through the food chain.
ABSTRACT
Enterococci are part of the indigenous microbiota of human gastrointestinal tract and food of animal origin. Enterococci inhabiting non-human reservoirs play a critical role in the acquisition and dissemination of antimicrobial resistance determinants. The aim of this work was to investigate the antimicrobial resistance in Enterococcus faecalis and Enterococcus faecium strains recovered from artisanal food of animal origin. Samples of goat cheese (n = 42), cow cheese (n = 40), artisanal salami (n = 30), and minced meat for the manufacture of hamburgers (n = 60) were analyzed. Phenotypic and genotypic tests for species-level identification of the recovered isolates were carried out. Minimum inhibitory concentration (MIC) study for in vitro quantitative antimicrobial resistance assessment was performed, and 71 E. faecalis and 22 E. faecium were isolated. The recovered enterococci showed different multi-drug resistance patterns that included tretracycline, erythromycin, ciprofloxacin, linezolid, penicillin, ampicillin, vancomycin, teicoplanin, gentamicin (high-level resistance), and streptomycin (high-level resistance). VanA-type E. faecium were detected. ß-lactamase activity was not observed. Artisanal foods of animal origin act as a non-human reservoir of E. faecalis and E. faecuim strains, expressing multi-resistance to antimicrobials. In conclusion, the implementation of a continuous antimicrobial resistance surveillance in enterococci isolated from artisanal food of animal origin is important.
Subject(s)
Drug Resistance, Multiple, Bacterial , Enterococcus faecalis/drug effects , Enterococcus faecalis/isolation & purification , Enterococcus faecium/drug effects , Enterococcus faecium/isolation & purification , Food Microbiology , Animals , Anti-Bacterial Agents/pharmacology , Argentina , Bacterial Proteins/genetics , Bacterial Proteins/isolation & purification , Bacterial Proteins/metabolism , Carbon-Oxygen Ligases/genetics , Carbon-Oxygen Ligases/isolation & purification , Carbon-Oxygen Ligases/metabolism , Cattle , Ciprofloxacin/pharmacology , Dairy Products/microbiology , Food Contamination/analysis , Genotype , Gentamicins/pharmacology , Goats , Meat Products/microbiology , Microbial Sensitivity Tests , Penicillins/pharmacology , Phenotype , Streptomycin/pharmacology , Teicoplanin/pharmacology , Vancomycin/pharmacology , beta-Lactamases/metabolismABSTRACT
Se informan dos casos de celulitis cutánea en trabajadores de un mismo criadero de aves a corral del área rural de la ciudad de Tandil, Argentina. En ambos pacientes fue identificado E. rhusiopathiae a partir de cultivos de muestras obtenidas por biopsia. La investigación del reservorio evidenció que en todas las muestras de las excretas de aves y en dos muestras de los residuos del alimento, se aisló E. rhusiopathiae con idéntico perfil bioquímico y de resistencia antimicrobiana al de las cepas aisladas de los dos casos clínicos. Si bien son necesarios estudios moleculares para establecer la relación epidemiológica entre las cepas aisladas de los pacientes y las del criadero, se puede inferir que la fuente de infección humana fue el criadero extensivo de aves de corral.
This report describes two cases of cutaneous cellulitis in workers at the same poultry farm in the rural area of Tandil, Argentina. In both patients E. rhusiopathiae was identified from culture samples obtained through biopsy. Investigation of the reservoir showed that, in all samples of fowl waste and in 2 samples of feed, E. rhusiopathiae was isolated with identical biochemical and antibiotic resistance profiles to those of the isolated strains in the case reports. Even though molecular analyses are required to establish an epidemiologic relation between the strains found in the patients and those on the farm, it can be inferred that the source of human infection was the extensive poultry farm.
Subject(s)
Humans , Male , Adult , Middle Aged , Cellulite , Erysipelothrix , Poultry , Rural Workers , MicrobiologyABSTRACT
We evaluate the prevalence of intestinal parasites in 504 people and the degree of association between environmental variables and parasites found in population, soil and water in a rural area of Argentina during 2002-2003. A structured survey was used to evaluate the environmental variables and fecal-human, soil and water samples were analyzed. The prevalence of parasites was 45.4%. Most prevalent protozoa were Blastocystis hominis (27.2%) and Giardia lamblia (6.9%), while the most prevalent helminth was Ascaris lumbricoides (3.8%). The analyzed environmental variables showing association (p < 0.05) with presence of parasites in population were: cardboard-tin or wooden house, dirt floor, home or communal water pump, faucet outside the house or public faucet and cesspool or latrine. Parasite forms were found in 82.3% of the soil samples and in 84.2% of the water samples. In both samples we found parasites that were also found in people. In this study we have found deficient sanitary conditions associated with presence of parasites in population and we have evidenced that contaminated soil and water were the source of these parasites.
Subject(s)
Helminthiasis/epidemiology , Intestinal Diseases, Parasitic/epidemiology , Protozoan Infections/epidemiology , Animals , Argentina/epidemiology , Humans , Prevalence , Rural Population , Sanitation , Socioeconomic Factors , Soil/parasitology , Urban Population , Water/parasitologyABSTRACT
The work described in this paper presents an evaluation of disinfection by-products generation in four different biological treatment plant effluents, making use of sodium hypochlorite and sodium ferrate (IV) at varying concentration and reaction time. Correlations between pH, chemical oxygen demand, total organic carbon, ammonium nitrogen, combined chlorine and trihalomethanes (THMs) and haloacetic acids (HAAs) were carried out. Disinfection by-products generation presented a direct relation with concentration and sodium hypochlorite reaction time. For the highest hypochlorite concentration employed (20 mg L(-1)) and highest reaction time (168 h), the THMs total did not exceed 312.96 microg L(-1), a value that lies below the Brazilian emission standard for treated effluents (1 mg L(-1) of chloroform). The THMs presented an inverse correlation with ammonium nitrogen, when inverse (R(2) = 0.646; P < 0.001) and exponential (R(2) = 0.707; P < 0.001) function were used. As per HAAs this same relation was observed for logarithmic (R(2) = 0.0397 P < 0.001) and exponential (R(2) = 0.508; P < 0.001) functions. The more nitrified the effluent, the bigger the chlorinated disinfection by-product generation. The disinfectant sodium ferrate (IV) does not lead to halogenated by-product formation.
Subject(s)
Acetates/analysis , Disinfectants/chemistry , Iron/chemistry , Quaternary Ammonium Compounds/chemistry , Sodium Hypochlorite/chemistry , Sodium/chemistry , Trihalomethanes/analysis , Water Pollutants, Chemical/analysis , Brazil , Data Interpretation, Statistical , Evaluation Studies as Topic , Industrial Waste , Quaternary Ammonium Compounds/analysis , Sewage , Time Factors , Waste Disposal, Fluid , Water Pollutants, Chemical/chemistry , Water Purification/methodsABSTRACT
The phenomenon known as one-trial tolerance (OTT) to the anxiolytic effects of benzodiazepines observed in rats submitted to the elevated plus-maze test (EPM) is considered to be due to the emergence of phobic states across the test/retest sessions. Antinociception is a usual component of the defense reaction. Until now, no study has examined antinociception and OTT together in freely behaving rats in the EPM. This work is a new approach looking at the sensorimotor gatings underlying OTT through the examination of the changes in reactivity to noxious stimuli during OTT development. We used the tail-flick test to assess the reactivity of rats to noxious stimulus during the effects of midazolam in test/retest sessions using two types of EPM, one with opaque (standard EPM) and another one with transparent walls (modified EPM). The authors had previously shown that this modified test caused an overall stressful situation more related to anxiety while the standard test coursed with a mixture of anxiety and high fear levels. In both plus mazes, the study was conducted in two experiments: (i) midazolam before the first trial, and (ii) midazolam before the second trial. In each experimental condition the effects of midazolam were tested under two doses (0.5 and 1.0 mg/kg) against a control group that received injections of saline. The anxiolytic effects of midazolam were more pronounced in animals tested in the modified EPM than in the standard EPM. Stressful stimuli present in both types of maze were able to elicit one-trial tolerance to midazolam on re-exposure. However, anxiolytic-insensitive behaviors in the first and the reduction in exploratory activity in the second trial are more pronounced in the standard EPM indicating that this test is more prone to transfer fear-related states across trials than the modified maze test. Antinociception is not present upon the re-exposure of rats to the EPM. These findings show that animals tested in the modified EPM showed higher sensitivity to the anxiolytic effects of midazolam than the standard EPM. Antinociception was not a concomitant of the shift in the emotional state present in the retest sessions of the EPM. These results are in agreement with the premises that repeated stressful experience leads to anxiolytic-insensitive fear state different from anxiety.
Subject(s)
Analgesia , Anti-Anxiety Agents/pharmacology , Anxiety/psychology , Fear/drug effects , Fear/physiology , Midazolam/pharmacology , Animals , Behavior, Animal/drug effects , Exploratory Behavior/drug effects , Male , Pain Measurement/drug effects , Physical Stimulation , Rats , Reaction Time/drug effectsABSTRACT
The aim of this study was to relate personal data, socio-cultural and environmental characteristics, and the presence of symptoms/signs with the frequencies of Giardia spp. and Blastocystis hominis among a rural population in Buenos Aires Province, Argentina. Of the surveyed population (350), 3.7% were infected with only Giardia spp. or 22.9% with B. hominis, and 2.3% were infected with both protozoa. The frequency of infection according to sex; 6.1% of males were infected and 1.6% of females by Giardia spp., 26.7% and 19.5% by B. hominis, and 2.4% and 2.2% by both parasites, respectively. Giardia spp. was detected in only three adults (over 14 years), but B. hominis was more frequent in adults than in children. The prevalences of these protozoa in this community are lower than those reported by other Argentinean studies, which is probably associated with the low density of the studied population (5.95 inhab/km2). Statistical analysis revealed that a male sex, flooding of the home, the use of a latrine, and an abdominal pain were correlated with the presence of these parasites, which indicate the importance of these factors in rural communities.
Subject(s)
Blastocystis Infections/epidemiology , Blastocystis hominis/isolation & purification , Giardiasis/epidemiology , Adolescent , Adult , Age Factors , Animals , Argentina/epidemiology , Child , Feces/parasitology , Female , Giardia/isolation & purification , Health Surveys , Humans , Hygiene , Male , Population Density , Prevalence , Rural Population , Sex FactorsABSTRACT
AIM: To evaluate the relationships between the personal, sociocultural, and environmental characteristics, and the presence or absence of symptoms with the detection of Enterobius vermicularis (E. vermicularis) in a population sample in our region (General Mansilla, Province of Buenos Aires, Argentina), by individual and familiar analyses. METHODS: E. vermicularis was diagnosed in 309 people from 70 family units residing in the urban area and the rural area of the city of General Mansilla. Each of them was surveyed so as to register personal, environmental and sociocultural data. Questions about the presence or absence of anal itch, abdominal pain and sleeping disorder were also asked. Significant associations were determined by square chi tests. Logistic regression models were adjusted by using a backward conditional stepwise method to determine the presence of this parasite in the individuals and in the families. RESULTS: The parasites were found in 29.12% (90/309) of the individuals, with a frequency of 14.28% (20/140) among the heads of the families and of 41.42% (70/169) among the children. The only variables showing a significant association were affiliation, where the risk category was "being the son/daughter of", and the symptoms were abdominal pain, sleeping disorder, and anal itch. Families with a member infected with parasite were considered Positive Families (PF) and they were 40/70 (57.14%), only 5% (2/40) of the PF had 100% of their members infected with the parasite. The logistic regression models applied showed that the risk categories were mainly affiliation (son/daughter) and housing (satisfactory) among others. CONCLUSION: The presence of E. vermicularis was proved in one third of the studied population. The frequency of families with all their members infected with the parasite was very low. Most of the studied personal, sociocultural, and environmental variables did not turn out to be significantly associated with the presence of the parasite. An association with the category of "son/daughter" and housing classified as "satisfactory" was determined. The latter may be due to the fact that the people living in that category of housing have hygienic practices at home that favour the distribution of the eggs in the environment. The presence of the analysed symptoms was associated with the presence of the parasite, thus strengthening the need of periodical control of the population showing at least one of these symptoms.
Subject(s)
Enterobiasis/epidemiology , Enterobius , Abdominal Pain/epidemiology , Abdominal Pain/parasitology , Adult , Anal Canal , Animals , Argentina/epidemiology , Child , Family Health , Female , Humans , Male , Pruritus/epidemiology , Pruritus/parasitology , Risk Factors , Rural Population , Sanitation , Socioeconomic Factors , Urban PopulationABSTRACT
It has been suggested that antinociception is part of the animal's defensive reaction to threatening situations. Chemical or electrical stimulation of the ventrolateral portion of the periaqueductal gray (vlPAG) produces both defensive freezing behavior and antinociception, supporting the view that the vlPAG is a critical structure in the coordination of the defensive reaction. The present study indicated that electrical stimulation of the vlPAG, at a current intensity sufficient to induce defensive freezing, caused a decrease in reactivity to a phasic escapable noxious stimulus (as measured in the tail-flick test) and to a tonic, inescapable noxious stimulus (as measured in the formalin test). These antinociceptive effects were reversed by microinjections of the opioid antagonist naltrexone or the specific 5-HT2A receptor antagonist ketanserin into the stimulation sites. These results suggest that (a) activation of neural circuits of the vlPAG, responsible for the production of freezing behavior, reduces the reactivity to nociceptive stimuli (as evaluated by the tail-flick and formalin tests) and that (b) opioid- and 5-HT2A-mediated mechanisms are called into action for regulating the antinociceptive response that accompanies the freezing behavior induced by vlPAG stimulation.
Subject(s)
Formaldehyde , Pain Measurement/drug effects , Pain/physiopathology , Periaqueductal Gray/physiology , Reaction Time/drug effects , Receptor, Serotonin, 5-HT2A/physiology , Receptors, Opioid/physiology , Algorithms , Animals , Electric Stimulation , Ketanserin/administration & dosage , Ketanserin/pharmacology , Male , Microinjections , Naltrexone/administration & dosage , Naltrexone/pharmacology , Narcotic Antagonists/administration & dosage , Narcotic Antagonists/pharmacology , Pain/chemically induced , Rats , Rats, Wistar , Serotonin Antagonists/administration & dosage , Serotonin Antagonists/pharmacology , Stereotaxic TechniquesABSTRACT
Con el objeto de recuperar e identificar contaminantes parasitarios se estudiaron muestras de suelo de todos los paseos públicos del área urbana de La Plata, Argentina. Se analizaron 23 paseos durante los meses de marzo y abril de 2000 y al mismo tiempo se evaluó el pH y la humedad de cada muestra. Se observaron 552 elementos parasitarios, 98 correspondieron a quistes de protozoos, 106 a huevos de helmintos y 348 a larvas de nematodos. Se demostró que los suelos de los paseos analizados estaban contaminados con parásitos de origen humano y animal
Subject(s)
Humans , Intestines , Soil Microbiology , Environmental Pollution , Argentina , Eukaryota , Helminths , Hydrogen-Ion Concentration , Nematoda , Parasite Egg Count , Recreational Zones , Urban AreaABSTRACT
A survey for intestinal parasites was performed on 38 individuals within the urban area of La Plata city (province of Buenos Aires, Argentina). This community is composed of brick-factory workers who also live in the factory premises. An analysis for intestinal parasites was done on fecal samples collected serially and by means of anal swabs and there after preserved in formol solution. At the same time, the ocurrence of the parasites under study as well as that of commensal organisms was investigated in water and soil samples within the factory environs. Information was also obtained from the members of this community as their age, sex, birthplace and recent travels, either abroad or to the interior of Argentina. The prevalence of the pathogens and commensal parasites was 89,5 percent. The frecuency of protozoans and helminths was: G. lamblia 26,3 percent; B. hominis 65,8 percent; A. lumbricoides 7,9 percent; H. nana 2,6 percent; uncinaria sp. 7,9 percent; S. stercoralis 2,6 percent and E. vermicularis 42,1 percent. None of these parasite or commensal organisms were present in the water samples investigated. Four out of 20 soil samples analyzed contained parasitic elements T. canis eggs (one); G. liamblia cysts (two) and A. lumbricoides eggs (one). These results indicated that most important factors causing such a high prevalence of coproparasites were the poor conditions of personal and community hygiene in combination with the frequent travels to the north and the northeast of the country, regions which are endemic parasitic areas. The implementation of programs on health education and communal sanitation would contribute in the control of this health problem