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AIMS: This study investigated the diversity of Colletotrichum isolates recovered from Conyza bonariensis leaves through the use of morphological characteristics, growth rate, carbon sources utilization and phylogenetic analysis. METHODS AND RESULTS: In all, 30 Colletotrichum isolates recovered from C. bonariensis leaves showing symptoms of disease were included in the present study. Based on the analysis of morphology and sequences, the isolates were distributed into six Colletotrichum species complexes. The concatenated alignment of GAPDH and ITS sequences showed that 20 out of 30 isolates were included in four species complexes which comprise the most important pathogens causing anthracnose in soybean or anthracnose and stalk rot in maize: C. truncatum, C. orchidearum, C. gloeosporioides and C. graminicola. The remaining 10 isolates were included in the C. boninense and C. destructivum species complexes or could not be assigned to any complex with the available information. CONCLUSION: Weeds belonging to genus Conyza are host to soybean and maize potential pathogenic species of Colletotrichum and could have a role as inoculum reservoir for cross contamination in the agroecosystem. SIGNIFICANCE AND IMPACT OF THE STUDY: The combined use of morphological, kinetics and physiological parameters of growth and phylogenetic analysis in Colletotrichum isolates from Conyza leaves allowed the detection of species complexes previously not identified in Argentina.

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INTRODUCTION: The surgical treatment of acromioclavicular dislocation remains controversial. We describe herein a combined two-stage technique that includes an arthroscopic approach followed by a mini-invasive approach. MATERIAL AND METHODS: 41 patients with acromioclavicular dislocation grades III, IV and V. Acute and chronic lesions and revision surgeries were included during the follow-up. Patients with other shoulder conditions were excluded. Mean age was 28.6 years. Patients were assessed preoperatively with the UCLA and Constant scores, and the pain visual analog scale. The 6- and 12-month postoperative evaluation included X-rays to assess coronal and axial stability, coracoclavicular ossifications, signs of acromioclavicular arthrosis and/or distal clavicular osteolysis. RESULTS: The Constant scores were as follows: 41.3 preoperatively; 89.4 at 6 months; 92.3 at 12 months. The UCLA scores were as follows: 21.7 preoperatively; 29.1 at 6 months; 31.4 at 12 months. The VAS scores were 8.4, 2.3 and 1.2, for the same periods respectively. Two cases had repeated injury due to trauma and one case was dissatisfied with the cosmetic appearance of the scar. The X-ray assessment showed two cases of loss of stability and one case of distal clavicular osteolysis. CONCLUSION: The combination of two reduction methods, a synthetic one and a biological one allows for a solid anatomical reconstruction that is stable in the coronal and axial planes and good medium-term results.

INTRODUCCIÓN: el tratamiento quirúrgico de la luxación acromioclavicular es aún motivo de controversia. En esta publicación se describirá una técnica combinada en la que se realizó un primer tiempo artroscópico y un segundo tiempo con abordaje miniinvasivo. MATERIAL Y MÉTODOS: 41 pacientes con luxación acromioclavicular grados III, IV y V. Para el seguimiento se incluyeron luxaciones agudas, crónicas y cirugías de revisión; se excluyeron pacientes con otras patologías de hombro, la edad promedio fue de 28.6 años. Los pacientes fueron evaluados con el. RESULTADOS: score de UCLA Constant, la escala visual analógica para dolor preoperatorio y control radiológico para evaluar la estabilidad tanto en plano coronal como axial, osificaciones coracoclaviculares, signos de artrosis acromioclavicular y/o osteólisis distal de clavícula a los 6 y 12 meses postoperatorio. se obtuvo un score de Constant preoperatorio de 41.3; 6 meses: 89.4; 12 meses: 92.3. El. CONCLUSIÓN: score de UCLA preoperatorio: 21.7; 6 meses: 29.1 y 12 meses: 31.4. VAS: 8.4; 2.3; 1.2. Hubo dos casos de relesión por trauma y un caso de insatisfacción estética de la cicatriz. En cuanto al examen radiológico se presentaron dos casos de pérdida de estabilidad y un caso de osteólisis distal de clavícula. la combinación de dos métodos de reducción, uno sintético y otro biológico, permitió una reconstrucción anatómica sólida, estable en plano coronal y axial con muy buenos resultados a mediano plazo.

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AIMS: The main purpose of this study was to determine whether the Arachis hypogaea L. root oxidative burst, produced at early stages of its symbiotic interaction with Bradyrhizobium sp. SEMIA 6144, and the bacterial antioxidant system are required for the successful development of this interaction. METHODS AND RESULTS: Pharmacological approaches were used to reduce both plant oxidative burst and bacterial peroxidase enzyme activity. In plants whose H2 O2 levels were decreased, a low nodule number, a reduction in the proportion of red nodules (%) and an increase in the bacteroid density were found. The symbiotic phenotype of plants inoculated with a Bradyrhizobium sp. SEMIA 6144 culture showing decreased peroxidase activity was also affected, since the biomass production, nodule number and percentage of red nodules in these plants were lower than in plants inoculated with Bradyrhizobium sp. control cultures. CONCLUSIONS: We demonstrated for the first time that the oxidative burst triggered at the early events of the symbiotic interaction in peanut, is a prerequisite for the efficient development of root nodules, and that the antioxidant system of bradyrhizobial peanut symbionts, particularly the activity of peroxidases, is counteracting this oxidative burst for the successful establishment of the symbiosis. SIGNIFICANCE AND IMPACT OF THE STUDY: Our results provide new insights into the mechanisms involved in the development of the symbiotic interaction established in A. hypogaea L. a legume infected in an intercellular way.

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Resumen: Introducción: el tratamiento quirúrgico de la luxación acromioclavicular es aún motivo de controversia. En esta publicación se describirá una técnica combinada en la que se realizó un primer tiempo artroscópico y un segundo tiempo con abordaje miniinvasivo. Material y métodos: 41 pacientes con luxación acromioclavicular grados III, IV y V. Para el seguimiento se incluyeron luxaciones agudas, crónicas y cirugías de revisión; se excluyeron pacientes con otras patologías de hombro, la edad promedio fue de 28.6 años. Los pacientes fueron evaluados con el score de UCLA Constant, la escala visual analógica para dolor preoperatorio y control radiológico para evaluar la estabilidad tanto en plano coronal como axial, osificaciones coracoclaviculares, signos de artrosis acromioclavicular y/o osteólisis distal de clavícula a los 6 y 12 meses postoperatorio. Resultados: se obtuvo un score de Constant preoperatorio de 41.3; 6 meses: 89.4; 12 meses: 92.3. El score de UCLA preoperatorio: 21.7; 6 meses: 29.1 y 12 meses: 31.4. VAS: 8.4; 2.3; 1.2. Hubo dos casos de relesión por trauma y un caso de insatisfacción estética de la cicatriz. En cuanto al examen radiológico se presentaron dos casos de pérdida de estabilidad y un caso de osteólisis distal de clavícula. Conclusión: la combinación de dos métodos de reducción, uno sintético y otro biológico, permitió una reconstrucción anatómica sólida, estable en plano coronal y axial con muy buenos resultados a mediano plazo.

Abstract: Introduction: The surgical treatment of acromioclavicular dislocation remains controversial. We describe herein a combined two-stage technique that includes an arthroscopic approach followed by a mini-invasive approach. Material and methods: 41 patients with acromioclavicular dislocation grades III, IV and V. Acute and chronic lesions and revision surgeries were included during the follow-up. Patients with other shoulder conditions were excluded. Mean age was 28.6 years. Patients were assessed preoperatively with the UCLA and Constant scores, and the pain visual analog scale. The 6- and 12-month postoperative evaluation included X-rays to assess coronal and axial stability, coracoclavicular ossifications, signs of acromioclavicular arthrosis and/or distal clavicular osteolysis. Results: The Constant scores were as follows: 41.3 preoperatively; 89.4 at 6 months; 92.3 at 12 months. The UCLA scores were as follows: 21.7 preoperatively; 29.1 at 6 months; 31.4 at 12 months. The VAS scores were 8.4, 2.3 and 1.2, for the same periods respectively. Two cases had repeated injury due to trauma and one case was dissatisfied with the cosmetic appearance of the scar. The X-ray assessment showed two cases of loss of stability and one case of distal clavicular osteolysis. Conclusion: The combination of two reduction methods, a synthetic one and a biological one allows for a solid anatomical reconstruction that is stable in the coronal and axial planes and good medium-term results.

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AIMS: We evaluated whether reactive oxygen species (ROS) production and the plant antioxidant system are involved in the symbiotic interaction between bradyrhizobia and legumes infected by crack entry, without intracellular infection threads (IT) formation, such as Arachis hypogaea L. (peanut). The role of bradyrhizobial Nod factors (NF) in modulating the plants' oxidative burst was also analysed. METHODS AND RESULTS: Histochemical and quantitative procedures were used to detect ROS levels in inoculated and in NF-treated peanut roots. Increase in root H2O2 production was determined at 10 min postinoculation with Bradyrhizobium sp. SEMIA 6144 or after NF addition. ROS production was modulated by NF. From 15 to 30 min postinoculation, the compatibility of Bradyrhizobium sp.-peanut interaction depends mostly on the H2O2 detoxification via catalase. CONCLUSIONS: We demonstrated for the first time that the early events of the symbiotic interaction in legumes invaded by crack entry trigger an increase in ROS production (represented exclusively by a higher H2O2 content) in which NADPH-oxidase seems not to be involved. NF modulate this response by enhancing the plant antioxidant machinery, contributing to the creation of adequate conditions for symbiosis development. SIGNIFICANCE AND IMPACT OF THE STUDY: Our data provide new insights into the mechanism involves in the symbiotic interaction that establish legumes infected by crack entry and suggest that ROS response shows differences compared with legumes invaded by IT formation.

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The objectives of the present study were: (i) to identify the frequency of cattle farms with a cohabitation of Amblyomma cajennense and Rhipicephalus microplus, (ii) to determine the status of susceptibility or resistance to acaricides used in Veracruz, Mexico, on A. cajennense populations and (iii) to identify factors associated with A. cajennense resistant to acaricides. Fifty farms were visited to determine the presence of ticks (A. cajennense and R. microplus) and to collect engorged A. cajennense individuals. From these, 24 A. cajennense populations were evaluated in resistance bioassays using discriminating doses of acaricides. The acaricides tested were organophosphates (chlorpiriphos, coumaphos and diazinon), pyrethroids (flumethrin, deltamethrin and cypermethrin), amidines (amitraz) and fipronil (a broad spectrum N-phenylpyrazole insecticide). A. cajennense infesting bovines were identified in 86% (43/50) of the farms visited, and 100% of the farms sampled (43/43) had cohabitation between R. microplus and A. cajennense. Of the farm owners or managers surveyed, 87.5% could not distinguish the morphological difference between tick genera. Populations of A. cajennense were 100%, 91.7% and 12.5% resistant to diazinon, coumaphos and chlorpyriphos (organophosphates), respectively, and 12.5% to amitraz, as were those susceptible to flumethrin and fipronil. In conclusions, populations of A. cajennense showed a high frequency of resistance to the organophosphates tested and to amitraz. Factors associated with the resistance to acaricides in A. cajennense were not identified.

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Nod factors are among the best-studied molecules implicated in the signal exchange that leads to legume-rhizobia symbiosis. The role of these molecules in symbiosis development has been primarily studied in legumes invaded through infection threads. In these plants, Nod factors generate several responses required for nodulation, including the induction of cortical cell division to form the nodule primordium. Arachis hypogaea L. (peanut) exhibits a specific mode of rhizobial infection and nodule morphogenetic programme in which infection threads are never formed. The role of Nod factors in this particular mechanism is unknown. In this work, a peanut symbiont mutant strain unable to produce Nod factors was obtained and characterised. The strain Bradyrhizobium (Arachis) sp. SEMIA 6144 V2 is altered in the nodC gene, which encodes an N-acetylglucosaminyl transferase involved in the first step of the Nod factor biosynthetic pathway. Further research revealed that, although its ability to colonise peanut roots was unaffected, it is not capable of inducing the division of cortical cells. The results obtained indicate that rhizobial Nod factors are essential for the induction of cortical cell division that leads to nodule primordium formation.

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Different laboratory cultures of the acarine tick Rhipicephalus (Boophilus) microplus (Canestrini, 1888) (Ixodida: Ixodidae) were infested by small Megaselia scalaris (Loew, 1866) (Diptera: Phoridae) flies. Larvae of this species exhibited opportunistic parasitism predominantly on engorged female ticks, causing severe damage to their cuticle through which the flies were able to reach R. microplus internal organs, on which they fed until developing into pupae in the tick's remains. The flies were kept by continuous propagation on fresh ticks over six generations during which the same parasitoid behaviour was observed. Here we report on an ixodid tick laboratory culture used for rearing M. scalaris.

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The leguminous crop Arachis hypogaea L. (peanut) is originally from South America and then was disseminated to tropical and subtropical regions. The dissemination of the crop resulted in peanut plants establishing a symbiotic nitrogen-fixing relationship with a wide diversity of indigenous soil bacteria. We present in this review, advances on the molecular basis for the crack-entry infection process involved in the peanut-rhizobia interaction, the diversity of rhizobial and fungal antagonistic bacteria associated with peanut plants, the effect of abiotic and biotic stresses on this interaction and the response of peanut to inoculation.

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Langerhans cells granulomatosis is a rare disease characterized by the clonal proliferation of the Langerhans cell, a cell element pertaining to the mononuclear phagocytes system. Hepatic involvement may be presented, particularly in the multifocal or disseminated form, together with the remaining surrounding organs. Radiologic findings have recently been reported including echographic, computerized tomography and magnetic resonance of the hepatic lesion of the disease. The case of a patient whose initial radiographic study suggested the existence of hepatic metastasis and which was later diagnosed with multifocal granulomatosis of Langerhans cells with hepatic involvement is reported. Radiologic and histologic images are provided and the data reported in the literature concerning this disease are reviewed.

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