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Context.— Disagreement exists within the pathology community about the status of the job market for pathologists. Although many agree that jobs in pathology were harder to come by earlier this decade, recent evidence suggests improvement is occurring. Objective.— To assess the state of the job market for pathologists. Design.— We analyzed data from the 2018 College of American Pathologists Practice Leader Survey. This survey contains data from 253 practice leaders on practices' hiring (and retrenchments) in 2017, the skills and level of experience being sought, success in filling those positions, and expectations for hiring in the next 3 years. Results.— Among the surveyed practice leaders, 115 (45.5%) sought to hire at least 1 pathologist in 2017, and together tried to fill 246 full-time equivalent positions that year, of which 93.5 full-time equivalents (38%) were newly created. This hiring was not limited to larger, academic-based practices, but also occurred among smaller practices and practices based in nonacademic hospitals, independent laboratories, and other settings. Although some practices retrenched (60 full-time equivalents in 2017), the net increase was a healthy 187 full-time equivalents. Practices most frequently sought pathologists who had at least 2 years of experience, but the level of experience identified with the “optimal” candidate varied by desired areas of subspecialty expertise. Practice leaders also reported expected growth in hiring, with the number of positions they hope to fill in the next 3 years exceeding those vacated by retirement. Conclusions.— Our findings support the proposition that the demand for pathologists is strong, at least at the current time.

Scab is an important disease of wheat throughout the world. Fusarium graminearum is the species most frequently isolated in Argentina. Histopathological modifications observed in Pro INTA Oasis (a susceptible Argentine cultivar) and in Sumai 3 (a resistant Chinese cultivar) from the time of inoculation, at the spike emergence stage, until major disease expression (10.5 days postinoculation in the susceptible cultivar) are described. Both cultivars showed a horizontal progression of disease, from anthers to glumes, and a vertical progression, from anthers to rachis. Chlorenchyma was the most damaged tissue, with progressive chlorosis and necrosis. Walls of mesophyll, parenchyma, and epidermal cells around the lesions became thicker, particularly in the resistant cultivar. Vessels and sieve tubes were occluded, particularly the former in the susceptible cultivar and the latter in the resistant cultivar. Possible relationships between tissue changes generated during disease progression and known resistance mechanisms are discussed.

Introduction Bacterial sexually transmitted infections (STIs) have an important impact on reproductive health, highlighting the increase in Chlamydia trachomatis infection rates among young people. To reduce the costs of STI detection, the pooling strategy is beneficial for high-throughput tests in low-prevalence populations using non-invasive samples. Objectives (1) To describe the performance of a 7-STI PCR assay using the pooling of three urine samples to detect C. trachomatis, Neisseria gonorrhoeae and Mycoplasma genitalium; (2) to estimate the cost saving of the pooling strategy; (3) to describe the prevalence, risk factors and coinfections of C. trachomatis, N. gonorrhoeae and M. genitalium in young people ≤25 years in Catalonia. Methods cross-sectional prevalence study conducted in 2016 among young people ≤25 years of age seen in sexual and reproductive health centres throughout Catalonia from pools of three urine samples. A standardized questionnaire was used to collect clinical-epidemiological and behavioural variables. Results 1032 young people were tested. The prevalence of C. trachomatis, N. gonorrhoeae and M. genitalium was 8.5%, 0.6% and 3.5%, respectively. The pooling strategy provided a 33% savings in reagent costs. Conclusions The pooling strategy implemented for epidemiological studies in our context provides a savings that has an impact on the viability of STI detection programmes. In the same way, this study shows that C. trachomatis prevalence continues to increase in this population and, for the first time in Catalonia, the prevalence of M. genitalium in young people is shown.

Obesity and overweight have increased at an alarming rate in the world during the last three decades. Obesity is a crucial factor in the development of metabolic abnormalities, including glucose intolerance, insulin resistance, metabolic syndrome, low-grade inflammation and oxidative stress. A similar scinario occurs during the aging process where alterations of the energetic metabolism homeostasis and a chronic systematic low-grade inflammation have been observed. Oxidative stress and poor physical performance can increase the risk of metabolic disease. Despite the diverse studies on the pathophysiological effects of obesity, its impact related to gender and through life, particularly during aging, hasn’t received a reasonable attention. The purpose of this review is to outline the pathophysiological mechanisms and metabolic alterations associated with obesity, with an emphasis on the monosodium glutamate (MSG)-induced obese model. MSG-induced obesity associated inflammation and declined adiponectin were more obvious in male mice, while glucose tolerance, insulin sensitivity and the redox balance were altered with increased age of both male and female mice. These findings indicate that the metabolic alterations in MSG-induced obesity are associated with the gender as well as aging. Therefore, the MSG obesity model is of a resonable value to underlie the relationship between gender, aging and metabolic alterations in obesity. In addition, we reviewed the medicinal plants and their active constituents which have been used to treat MSG-induced obesity. Given the significat value of this model, studies are needed to scrutinize the benificial effects and underlying mechanisms of medicinal plants with proven anti-obesity activity.

Urban forests, which are highly valuable for the urban environment, include trees from city streets that might be susceptible to wood-decay fungi. Fungal endophytes can colonize healthy plant tissues without causing external disease symptoms in standing trees. In this study, the diversity of endophytes isolated from wood of Platanus acerifolia (Aiton) Willd. from Buenos Aires, Argentina, is described and related to different levels of urban disturbance, tree age, and presence of wood-decay basidiomycetes. Samples were obtained from 28 asymptomatic trees (1643 wood core fragments) and 75 symptomatic trees (1516 wood sample fragments) from four sites with different levels of human disturbance. Fungal isolates were morphologically identified, and potential wood-decay isolates were phylogenetically analyzed. Twenty-seven endophytic taxa, including five basidiomycetes, were identified. The multivariate analysis suggested that the endophyte community of wood is highly influenced by the level of urban disturbance, followed by tree age and presence of potential pathogenic basidiomycetes.

SummaryX-linked spinal and bulbar muscular atrophy (SBMA) is characterized by adult-onset muscle weakness and lower motor neuron degeneration. SBMA is caused by CAG-polyglutamine (polyQ) repeat expansions in the androgen receptor (AR) gene. Pathological findings include motor neuron loss, with polyQ-AR accumulation in intranuclear inclusions. SBMA patients exhibit myopathic features, suggesting a role for muscle in disease pathogenesis. To determine the contribution of muscle, we developed a BAC mouse model featuring a floxed first exon to permit cell-type-specific excision of human AR121Q. BAC fxAR121 mice develop systemic and neuromuscular phenotypes, including shortened survival. After validating termination of AR121 expression and full rescue with ubiquitous Cre, we crossed BAC fxAR121 mice with Human Skeletal Actin-Cre mice. Muscle-specific excision prevented weight loss, motor phenotypes, muscle pathology, and motor neuronopathy and dramatically extended survival. Our results reveal a crucial role for muscle expression of polyQ-AR in SBMA and suggest muscle-directed therapies as effective treatments.

Modifying the length of the Huntington's disease (HD) CAG repeat, the major determinant of age of disease onset, is an attractive therapeutic approach. To explore this we are investigating mechanisms of intergenerational and somatic HD CAG repeat instability. Here, we have crossed HD CAG knock-in mice onto backgrounds deficient in mismatch repair genes, Msh3 and Msh6, to discern the effects on CAG repeat size and disease pathogenesis. We find that different mechanisms predominate in inherited and somatic instability, with Msh6 protecting against intergenerational contractions and Msh3 required both for increasing CAG length and for enhancing an early disease phenotype in striatum. Therefore, attempts to decrease inherited repeat size may entail a full understanding of Msh6 complexes, while attempts to block the age-dependent increases in CAG size in striatal neurons and to slow the disease process will require a full elucidation of Msh3 complexes and their function in CAG repeat instability.

Phytophthora sojae causes root and stem rot, one of the most important diseases of soybean worldwide. Genetic diversity of 32 Phytophthora sojae isolates of different geographic origin from Argentina was evaluated with RAPD markers. The isolates were collected from diseased soybean plants and soil samples from Santa Fe, Buenos Aires, C6rdoba and Entre Rios provinces, in the Pampeana Region. DNA was amplified with 20 decanucleotides primers. Seven primers amplified 49 fragments, of which 35 were polymorphic, indicating high variability. RAPD analysis detected intraspecific variability even among isolates of the same geographic origin.

Conocer las características de cepas fúngicas locales aumenta nuestra capacidad de poder hacer uso de sus propiedades e implementar, en consecuencia, nuevas y mejores formas de aprovechamiento de los recursos biológicos nativos. Con el fin de contribuir al conocimiento de estos organismos, en este trabajo se presentan descripciones detalladas y estudios de cultivo de 5 especies previamente reportadas como basidiomicetes endofíticos: Coprinopsis cinerea, Granulobasidium vellereum, Inonotus rickii, Phanerochaete chrysosporium y Trichosporon sporotrichoides, aisladas como endofitos de madera de plátanos de sombra (Platanus acerifolia) en la Ciudad de Buenos Aires, Argentina. Coprinopsis cinerea es descripta por primera vez en cultivo y se señalan las diferencias que presentan los cultivos de G. vellereum e I. rickii con reportes previos. Los caracteres de cultivo de P. chrysosporium y T. sporotrichoides no presentaron diferencias apreciables con descripciones previas. The knowledge of local fungal strains' features increases our ability to make use of their properties and to implement, in consequence, new and better ways of using the native biological resources. To contribute to the knowledge of these organisms, in this work we present descriptions and cultural studies of 5 species previously reported as endophytic basidiomycetes: Coprinopsis cinerea, Granulobasidium vellereum, Inonotus rickii, Phanerochaete chrysosporium and Trichosporon sporotrichoides, isolated from wood of London plane trees (Platanus acerifolia) in Buenos Aires City, Argentina. Coprinopsis cinerea is described in culture for the first time and differences in cultures of G. vellereum and I. rickii with previous reports are listed. Culture characters of P. chrysosporium and T. sporotrichoides did not show appreciable differences with previous descriptions. Fil: Robles, Carolina Analía. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Micología y Botánica. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Micología y Botánica; Argentina Fil: Lopez, Silvia Edith. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Micología y Botánica. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Micología y Botánica; Argentina Fil: Carmaran, Cecilia Cristina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Biodiversidad y Biología Experimental; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Micología y Botánica. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Micología y Botánica; Argentina

Trees in urban landscapes provide a wide range of benefits to the environment; however, they are exposed to several stress factors that can make them vulnerable to decay by fungi. The presence and identity of wood decay Basidiomycetes affecting Platanus acerifolia, a common tree used in cities, were evaluated in sites with different levels of urban disturbances in order to analyze the relationships between human disturbance level, tree age, fungal pathogens and their degradative potential. We carried out morphological and cultural descriptions of the fungi detected, and studied their decay capacity. Eight species of Basidiomycetes were detected, being Inonotus rickii the most frequently isolated and the most widely distributed in the areas sampled. Bjerkandera adusta, although rarely detected, caused the greatest loss of dry weight. In some cases phylogenetic analyses were performed under both static and dynamic homologies. The age of the trees (estimated from DBH values) sampled seemed to be more important as a predisposing factor for decay tan anthropogenic distubance of sites. The correlation between tree age, presence and identity of fungi, degradative potential and environment conditions is dicussed. Fil: Robles, Carolina Analía. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Micología y Botánica. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Micología y Botánica; Argentina Fil: Carmaran, Cecilia Cristina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Micología y Botánica. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Micología y Botánica; Argentina Fil: Lopez, Silvia Edith. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Micología y Botánica. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Micología y Botánica; Argentina

Efectos De La Reestructuración En El Clima Organizacional: El Caso Del Área De Una Dependencia Pública

Sixty-six fungi isolated from cyclamen phylloplanes were identified and assessed in vitro for antagonism to B. cinerea on leaves, petals, petioles and peduncles. The estimation of pathogen conidial production was used as indicator of biocontrol ability of each of the strains. They were classified by cluster analysis resulting in four categories according to their behavior in the different organs. The most promising category included 34 isolates that significantly reduced pathogen inoculum in all the organs. Correspondence analysis showed association among leaf isolations, strains of Clonostachys rosea and Penicillium spp. and the best biocontrol performance. The statistical analysis was successful in dealing with this complex set of experimental data. Leaf fungal diversity was higher than those of petals and petiols, with Shannon values of 2.7, 0.9 and 0.5 respectively. Evidence for antibiosis and hyperparasitism was found for C. rosea. Fil: Rivera, Marta Carolina. Universidad de Buenos Aires. Facultad de Agronomía; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Lopez, Maria Virginia. Universidad de Buenos Aires. Facultad de Agronomía; Argentina Fil: Lopez, Silvia Edith. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Micología y Botánica. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Micología y Botánica; Argentina

Genetically precise models of Huntington's disease (HD), Hdh CAG knock-in mice, are powerful systems in which phenotypes associated with expanded HD CAG repeats are studied. To dissect the genetic pathways that underlie such phenotypes, we have generated Hdh(Q111) knock-in mouse lines that are congenic for C57BL/6, FVB/N and 129Sv inbred genetic backgrounds and investigated four Hdh(Q111) phenotypes in these three genetic backgrounds: the intergenerational instability of the HD CAG repeat and the striatal-specific somatic HD CAG repeat expansion, nuclear mutant huntingtin accumulation and intranuclear inclusion formation. Our results reveal increased intergenerational and somatic instability of the HD CAG repeat in C57BL/6 and FVB/N backgrounds compared with the 129Sv background. The accumulation of nuclear mutant huntingtin and the formation of intranuclear inclusions were fastest in the C57BL/6 background, slowest in the 129Sv background and intermediate in the FVB/N background. Inbred strain-specific differences were independent of constitutive HD CAG repeat size and did not correlate with Hdh mRNA levels. These data provide evidence for genetic modifiers of both intergenerational HD CAG repeat instability and striatal-specific phenotypes. Different relative contributions of C57BL/6 and 129Sv genetic backgrounds to the onset of nuclear mutant huntingtin and somatic HD CAG repeat expansion predict that the initiation of each of these two phenotypes is modified by different genes. Our findings set the stage for defining disease-related genetic pathways that will ultimately provide insight into disease mechanism.

Background In Huntington's disease (HD), an expanded CAG repeat produces characteristic striatal neurodegeneration. Interestingly, the HD CAG repeat, whose length determines age at onset, undergoes tissue-specific somatic instability, predominant in the striatum, suggesting that tissue-specific CAG length changes could modify the disease process. Therefore, understanding the mechanisms underlying the tissue specificity of somatic instability may provide novel routes to therapies. However progress in this area has been hampered by the lack of sensitive high-throughput instability quantification methods and global approaches to identify the underlying factors. Results Here we describe a novel approach to gain insight into the factors responsible for the tissue specificity of somatic instability. Using accurate genetic knock-in mouse models of HD, we developed a reliable, high-throughput method to quantify tissue HD CAG repeat instability and integrated this with genome-wide bioinformatic approaches. Using tissue instability quantified in 16 tissues as a phenotype and tissue microarray gene expression as a predictor, we built a mathematical model and identified a gene expression signature that accurately predicted tissue instability. Using the predictive ability of this signature we found that somatic instability was not a consequence of pathogenesis. In support of this, genetic crosses with models of accelerated neuropathology failed to induce somatic instability. In addition, we searched for genes and pathways that correlated with tissue instability. We found that expression levels of DNA repair genes did not explain the tissue specificity of somatic instability. Instead, our data implicate other pathways, particularly cell cycle, metabolism and neurotransmitter pathways, acting in combination to generate tissue-specific patterns of instability. Conclusion Our study clearly demonstrates that multiple tissue factors reflect the level of somatic instability in different tissues. In addition, our quantitative, genome-wide approach is readily applicable to high-throughput assays and opens the door to widespread applications with the potential to accelerate the discovery of drugs that alter tissue instability.

Blueberries (Vaccinium corymbosum) have recently become an important alternative crop in different ecological regions of Argentina. In surveys, a new disease characterized by leaf spots and twig and shoot blight has been observed on plants cultivated in Arrecifes, Mercedes, and San Pedro (provinces of Buenos Aires) and Concordia (province of Entre Ríos) since July 2004. Spots initially appear brown, circular, 1 to 2 mm in diameter, and irregularly distributed on the leaves and they eventually coalesce. Fruiting twig and shoot blight developed from the tips toward the base. Affected plants of cvs. O'Neal and Reveille were distributed randomly in the field and with a low incidence (average of 2%). The objective of this work was to identify the causal agent of this disease. Symptomatic plant material was surface disinfested with 0.2% NaOCl for 1 min and 70% ethanol for 1 min, washed once with sterile distilled water, blotted dry with paper towels, and plated on potato dextrose agar. Colonies were initially white, becoming light to dark gray with the onset of sporulation with black, sphaerical to subsphaerical conidia that measured 14 to 19 × 12 to 16 μm. These characteristics agree with published descriptions of Nigrospora sphaerica (Sacc.) Mason (1,4). To evaluate pathogenicity, all leaves, petioles, and stems of seven healthy potted plants of cv. O'Neal were punctured with flamed needles and sprayed with a suspension of 1 × 108 spores of the fungus per milliliter of sterile distilled water. Another seven nonwounded plants were sprayed with the spore suspension. Seven plants similarly injured and seven nonwounded plants were sprayed with sterile distilled water and served as controls. Each plant was covered with a water-sprayed polyethylene bag and maintained in a controlled environment chamber at 20°C with a 12-h photoperiod. The bags were removed after 3 days. All wounded inoculated plants began to show disease symptoms similar to those observed in the field 20 days after inoculation. Controls and nonwounded inoculated plants remained symptomless. The pathogen was reisolated from diseased tissues fulfilling Koch's postulates. N. sphaerica is a well-known saprophyte on many plant species but has been mentioned as pathogen on many hosts (2,3). To our knowledge, this is the first reference of N. sphaerica as a wound pathogen of blueberry. In the field, the fungus would have gained access to the plant through wounds caused by insects or frost after a long-term wetness duration. References: (1) M. B. Ellis. Dematiaceous Hyphomycetes. CMI, Kew, Surrey, UK, 1971. (2) D. F. Farr et al. Fungi on Plants and Plant Products in the United States. American Phytopathological Society, St. Paul, MN, 1989. (3) D. F. Farr et al. Fungal Databases. Systematic Botany and Mycology Laboratory. Online publication. ARS, USDA. 2007. (4) E. W. Mason. Trans. Brit. Mycol. Soc. 12:152, 1927.

Asian soybean rust (ASR), caused by Phakopsora pachyrhizi, is the most destructive disease of soybean (Glycine max) in many areas of the world. ASR was first detected in Argentina during 2002 in a limited area in the northern region of the country (2). During the 2004 growing season, P. pachyrhizi spread rapidly throughout most soybean growing areas of northwestern and northeastern Argentina. ASR was also was found in some fields in Entre Ríos and Santa Fe provinces. In all areas, symptoms were expressed late in the 2004 season (growth stages R5.5 to R7) and yield losses were minimal. The objectives of this study were to quantify P. pachyrhizi infection in the canopy and morphologically characterize the fungus from fields where it had been previously detected by polymerase chain reaction (PCR) (3). Incidence (percentage of plants affected) and severity (percentage of leaf area affected, including chlorosis) were visually estimated for 10 plants arbitrarily collected (April 2004) from each of three fields located in Charata (Chacabuco), Chaco Province (Sample 1, collected in the R6 stage), La Paloma (Moreno), Santiago del Estero Province (Sample 2, stage R6 to R7), and Tolloche (Anta), Salta Province (Sample 3, stage R5.5). Disease assessments were made for the lower, middle, and upper canopy from 15 leaves per plant. The number of pustules per cm2 and uredinia per lesion were recorded from the undersides of central leaflets for each trifoliolate observed. Tissue sections were made to observe fructifications of P. pachyrhizi. Incidence of affected plants was 100% in all fields. Disease severity for Sample 1 was 45% (range 30 to 60%), 20% (10 to 30%), and 10% (5 to 20%) for the lower, middle, and upper canopy, respectively; for Sample 2: 60% (30 to 80%), 40% (25 to 50%), and 25% (15 to 40%) for the lower, middle, and upper canopy, respectively; and for Sample 3: 25% (10 to 50%), 15% (10 to 20%), and 10% (5 to 15%) for the lower, middle, and upper canopy, respectively. The number of pustules per cm2 for Sample 1 was 156/cm2 (range 88 to 200); Sample 2: 172/cm2 (128 to 232); and Sample 3: 120/cm2 (72 to 232). The number of uredinia per lesion for Sample 1 was 6 per lesion (range 1 to 15); Sample 2: 5.5 per lesion (1 to 13), and Sample 3: 2.8 per lesion (1 to 5). The two spore types that were commonly observed were urediniospores and teliospores. Telia were found on infected leaves mixed with uredinia in every sample. Urediniospores measured 16 to 22 μm (mean 18.5 μm) × 25 to 30 μm (mean 27 μm). Teliospores measured 8 to 11 μm (mean 9 μm) × 19 to 27 μm (mean 23.8 μm). Spores sizes are in the range described by Ono et al. (1). To our knowledge, this is the first report of epidemiological and morphological characterization of ASR in Argentina and the first report of the telial stage of P. pachyrhizi on soybean in South America. Fil: Carmona, Marcelo Anibal. Universidad de Buenos Aires. Facultad de Agronomía; Argentina Fil: Gally, Marcela Edith. Universidad de Buenos Aires. Facultad de Agronomía; Argentina Fil: Lopez, Silvia Edith. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Micología y Botánica. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Micología y Botánica; Argentina

During the spring of 2003, flower spots were observed on French hydrangea (Hydrangea macrophylla (Thunb.) DC) in CETEFFHO-INTA-JICA experimental greenhouses in Castelar, Argentina. Brown, irregular spots randomly distributed on petals were detected on an old, whiteflowering variety of unknown origin, cultivated by growers. Small pieces of diseased tissue were surface disinfested with 2% NaOCl, plated on 2% potato dextrose agar (PDA) with pH 7, and incubated at 22 to 24°C. Dense, whitish mycelium developed within 48 h and turned gray after 72 h. Conidia were ellipsoid, hyaline, nonseptate, and formed in botryose heads. Spores from 10-day-old colonies that were developed on PDA in test tubes were removed with 4 ml of sterile water per tube. Prior to inoculation, inflorescences were detached and placed in water-filled glass vases. To test pathogenicity, eight healthy inflorescences were sprayed with a 5-ml suspension (2 × 104 conidia per ml of sterile distilled water). Another eight healthy inflorescences were sprayed with sterile distilled water. The inflorescences were maintained at 21°C and covered with polyethylene bags that were removed after 3 days. Brown, circular-to-irregular spots appeared on petals 5 days after inoculation, became coalescent, and covered 50 to 60% of each inflorescence in 8 days. Gray mold consisting of black conidiophores and gray-in-mass conidia was observed 3 days after the development of the symptoms. Controls remained symptomless. The same pathogen was recovered from inoculated flowers and was identified as Botrytis cinerea Pers.:Fr. (1). To our knowledge, this is the first report of this fungus on Hydrangea macrophylla in Argentina. Reference: (1) M. V. Ellis and J. M. Waller. Sclerotinia fuckeliana (condial state: Botrytis cinerea).No. 431 in: Descriptions of Pathogenic Fungi and Bacteria, CMI, Kew, Surrey, UK, 1974.

Brown necrotic spots surrounded by chlorotic areas have been observed on the leaf margins of Spathiphyllum sp. in many nurseries in and near Buenos Aires, Argentina, since 1997. Spots reached 0.7 × 2 cm and appeared mainly on older leaves of stressed plants. To determine the causal agent of the leaf spot, small pieces of diseased tissue were surface-sterilized for 2 min in 2% sodium hypochlorite and plated on potato dextrose agar. Gray olivaceous to almost black colonies developed in 3 to 4 days. Dark conidiophores, which formed singly or in small groups, were short, less than 100 μm, sometimes flexuous, and occasionally geniculate. The brown to black, obclavate, pyriform, or rostrate conidia were 20 to 25 μm long × 10 to 15 μm wide, with three to four transverse septa and one to three longitudinal or oblique septa. Chains of conidia 5 to 10 spores long were sometimes branched, appearing bushy. The foliage of 15 healthy potted plants previously injured with sterile needles and 15 healthy potted plants without injuries was inoculated with a suspension of 2.8 × 104 conidia per ml. Plants were maintained at 23°C and 100% relative humidity under fluorescent light (12 h light/12 h darkness) for 3 days. Chlorotic and necrotic spots began to develop on the apex and margins of injured and inoculated leaves after 10 days. Lesions tended to coalesce, finally measuring 2.2 × 0.7 cm after 26 days. Control plants, with and without injuries, sprayed with distilled water remained symptomless. Koch's postulates were satisfied after reisolating the fungus. Cultures in potato carrot agar and V8 agar after 7 days exhibited typical characteristics of Alternaria alternata (2–4). An Alternaria sp. has been found previously in the United States on Spathiphyllum sp. (1). This is the first report of Alternaria leaf spot of Spathiphyllum in Argentina. References: (1) D. F. Farr et al. 1989. Fungi on Plants and Plant Products in the United States. The American Phytopathological Society, St. Paul, MN. (2) E. G. Simmons. Alternaria themes and variations (226–235): Classification of Citrus pathogens. Mycotaxon 70:263, 1999. (3) E. G. Simmons. Alternaria themes and variations (236–243): Host specific toxin producers. Mycotaxon 70:325, 1999. (4) E. G. Simmons and R. G. Roberts. Alternaria themes and variations (73). Mycotaxon 48:109, 1993.

La obesidad y el sobrepeso se han incrementado de forma alarmante en el mundo durante las tres últimas décadas, lo que ocurre desde la infancia hasta la vejez, debido principalmente a los cambios en el estilo de vida. La obesidad es un factor crucial en el desarrollo de anormalidades metabólicas, tales como intolerancia a la glucosa, resistencia a la insulina e inflamación con estrés oxidante. Un panorama similar ocurre durante el proceso de envejecimiento, donde se observa alteración de la homeostasis del metabolismo energético y un estado de inflamación crónica sistémica de bajo grado. El estrés oxidante y un pobre funcionamiento físico llevan a un incremento del riesgo para desarrollar enfermedades metabólicas. A pesar de los diversos estudios que se han realizado sobre los efectos fisiopatológicos de la obesidad, su impacto asociado al género y a lo largo de la vida, en especial durante el envejecimiento, no ha recibido atención. El propósito de esta investigación fue determinar el estado metabólico general en un modelo de ratones obesos hembra y macho a lo largo de la vida desde los 4 hasta los 20 meses de edad. La obesidad se indujo mediante la administración neonatal de glutamato monosódico (GMS), y posteriormente se cuantificaron parámetros bioquímicos, perfil inflamatorio, tolerancia a la glucosa y sensibilidad a la insulina. Además, se evaluó el daño oxidante y la protección antioxidante en diferentes órganos. Los resultados muestran que el Índice Lee (IL), así como los niveles de colesterol y triglicéridos se incrementaron gradualmente en todos los grupos a través del tiempo. En general, los ratones obesos GMS mostraron los niveles más altos de colesterol en comparación de sus controles. Las hembras GMS mostraron niveles más altos en el contenido de triglicéridos que los machos obesos. Se evaluó la función hepática midiendo las actividades de las enzimas AST y ALT, y se encontró que ambas enzimas se incrementaron conforme aumentó la edad en todos los grupos, siendo las hembras quienes mostraron mayores niveles de ALT. Con relación con el perfil inflamatorio, se encontró que en el grupo de machos, particularmente los ratones obesos GMS, presentaron niveles elevados de TNF-α, IL10 e IL-6 a los 12 meses de edad, comparado con el grupo de hembras. Los niveles de adiponectina disminuyeron gradualmente a lo largo de la vida de los ratones obesos y en sus controles; los machos mostraron niveles bajos de adiponectina comparado con las hembras. También se encontraron alteraciones en la tolerancia a la glucosa y en la sensibilidad a la insulina, tanto en hembras como en machos obesos GMS desde etapas jóvenes, conservándose esta diferencia hasta el envejecimientos. Sin embargo, los ratones obesos machos mostraron los niveles más altos en estas alteraciones. De manera notoria, los aumentos en estos parámetros disminuyeron a los 20 meses de edad sin encontrarse diferencias estadísticas entre los 4 grupos. Los parámetros oxidantes y antioxidantes, tanto en plasma como en hígado, pulmón, corazón y riñón permitió conocer la influencia del daño oxidante por obesidad durante el proceso de envejecimiento y la respuesta antioxidante. Los ratones obesos GMS mostraron alteraciones metabólicas y susceptibilidad asociada al género a lo largo de la vida y durante el proceso de envejecimiento. El entendimiento de las diferencias metabólicas entre los géneros durante la vida, permitirá el descubrimiento de estrategias preventivas específicas para las enfermedades crónicas y contra la pérdida de la funcionalidad por envejecimiento.

La célula senescente se caracteriza por encontrarse detenida en las fases iniciales del ciclo celular, presentar resistencia ante la apoptosis y por diversas alteraciones en la expresión génica. Poco se conoce acerca de las aberraciones transcriptómicas ocasionadas por la senescencia en células epiteliales de próstata, existe evidencia parcial de que estas perturbaciones podrían contribuir con la aparición y progresión de diversas enfermedades prostáticas. En este trabajo se analizó el transcriptoma de las células HPEC inducidas a senescencia por SIPS con el objetivo de determinar cuáles son las alteraciones en los patrones de expresión de diversos transcritos como mRNA, lncRNA, circRNA y miRNA. Una vez determinados los análisis de expresión diferencial génica se realizaron análisis de enriquecimiento de vías de señalización y términos ontológicos para conocer las funciones moleculares, biológicas y los componentes celulares que resultan afectados por las alteraciones en la expresión génica. Los resultados de esos enriquecimientos mostraron afectaciones en vías de señalización como como NRF2, TGF-β, VEGFA-VEGFR e IFNγ, ErbB, Hippo, MAPK, PI3K-Akt y Wnt. Asimismo, en las células HPEC inducidas SIPS se confirmó la presencia de 20 genes que ya han sido reportados en otros modelos como parte del núcleo de genes asociados a la senescencia. De ellos, 9 genes presentan la mayor cantidad de interacciones proteína – proteína y patrones de co-expresión. Además, se realizaron redes de interacción mRNA – miRNA y mRNA – mirRNA – CircRNA para tratar de encontrar los mecanismos de regulación que rigen la expresión de estos genes. Las alteraciones presentes en el transcriptoma de HPEC provocadas por la senescencia se asocian con procesos como carcinogénesis, metástasis, aparición y progresión de neoplasias, disminución de la respuesta inmunológica y aumento de resistencia a la apoptosis The senescent cell is characterized by being arrested in the cell cycle, presenting resistance to apoptosis, and having various alterations in gene expression. Little is known about transcriptomic aberrations caused by senescence in prostate epithelial cells, there is partial evidence that these disturbances could contribute to the appearance and progression of multiple prostate diseases. In this work, the HPEC transcriptome was analyzed after SIPS induction in order to determine the alterations in the expression patterns of various transcripts such as mRNA, lncRNA, circRNA, and miRNA. Once the differential gene expression (DGE) analysis was determined, enrichment analysis of signaling pathways and ontological terms were performed to find the molecular, biological functions, and cellular components that are affected by alterations in gene expression. The results of these enrichments showed effects on signaling pathways such as Nrf2, TGF-β, VEGFA-VEGFR and IFNγ, ErbB, Hippo, MAPK, PI3K-Akt, and Wnt. These alterations are associated with processes such as carcinogenesis, metastasis, neoplasms onset and progression, decreased immune response and increased apoptotic resistance. Also, in HPEC induced to SIPS, the presence of 20 genes that have already been reported in other models as part of the nucleus of genes associated with senescence, was confirmed; and 9 genes of the 20 present the highest number of interactions and co-expression patterns. Besides, mRNA-miRNA and mRNA-miRNA-circRNA interaction networks were made to try to find the regulatory mechanisms that govern the expression of these genes. The alterations present in the HPEC transcriptome caused by senescence are associated with processes such as carcinogenesis, metastasis, onset and progression of neoplasms, decreased immune response and increased resistance to apoptosis.

La senescencia celular (SC) es un fenómeno en el que las células detienen su proliferación después de un número limitado de duplicaciones o como respuesta ante el estrés. En la SC hay cambios en la expresión génica, nula respuesta ante estímulos apoptóticos o mitogénicos, y el desarrollo de un secretoma denominado “Fenotipo Secretor Asociado a la Senescencia” (SASP). La senescencia puede establecerse en distintos tipos celulares, sin embargo, el modelo más estudiado es el de fibroblasto. Las diferencias que existen entre los diversos tipos celulares, hacen suponer que las células epiteliales senescentes pudieran tener un comportamiento distinto a lo descrito en los fibroblastos. Se ha observado una asociación entre las patologías en próstata, el estrés oxidante y la presencia de células epiteliales senescentes, sin embargo se desconoce de qué manera la senescencia contribuye al establecimiento y desarrollo de esas patologías. El objetivo de esta investigación fue evaluar los parámetros de senescencia prematura inducida por estrés (SIPS) y los componentes del SASP de células epiteliales de próstata humana (HPEC) senescentes, así como los efectos de este secretoma sobre la proliferación celular. Para lo cual se indujo SIPS en las HPEC con 12 μM de H2O2, concentración menor a lo reportado en fibroblastos de pulmón de ratón y humano (75 μM). La respuesta a estímulos mitogénicos dada por el Factor de Crecimiento Epidermal (EGF) a HPEC senescentes fue nula. El análisis del SASP del día 4 después de SIPS, mostró incrementos en la expresión de las citocinas IL-6, IL-8, de las quimiocinas GROα/β/γ (CXCL1/CXCL2/CXCL3) y del factor estimulante de colonias de granulocitos/macrófagos (GM-CSF); sin embargo, para el día 9, la concentración de estos componentes disminuyó y no promovió la proliferación en un cultivo HPEC sometido a este SASP. Por lo tanto la respuesta al estrés para la inducción de SIPS en las HPEC es diferente de los fibroblastos, sin embargo, la expresión de marcadores del estado senescente p16, p21, p53 y β-gal, el comportamiento dinámico en los componentes del SASP y la respuesta nula ante estímulos mitogénicos es similar a lo reportado en fibroblastos.

La senescencia celular (SC) es un fenómeno biológico que ocurre en respuesta a daño y se ha relacionado con distintos procesos biológicos y patológicos. Gran parte del conocimiento que se tiene de la senescencia celular ha sido descrito en fibroblastos, sin embargo, este no es el único tipo celular en el que se presenta la senescencia. El establecimiento de la senescencia puede darse por estrés oxidante que induce daño en el ADN. Aspectos como el metabolismo energético y el estado redox de células senescentes es poco estudiado. En este trabajo se indujo senescencia en la línea celular MCF10A por estrés oxidante. Se determinó el metabolismo energético de células senescentes midiendo la tasa de consumo de oxigeno (OCR) y la tasa de acidificación del medio extracelular (ECAR). Así como, el estado redox evaluando la presencia de especies reactivas de oxigeno (ERO) y el coeficiente de glutatión oxidado y reducido (GSH/ GSSG). Nuestros resultados muestran que las células senescentes MCF10A inducidas a senescencia por estrés oxidante presentan un metabolismo energético preferentemente dirigido hacia la glucólisis, y un estado redox pro-oxidante, debido a una elevación en el contenido de GSSG que coincide con un aumento de las ERO.

El cáncer de mama es una de las neoplasias más frecuentes en todo el mundo y constituye la primera causa de muerte por cáncer en mujeres en México. Su elevada mortalidad se debe principalmente a su gran capacidad metastásica, la cual se asocia a la transición epitelio-mesénquima (TEM). Durante este proceso, se disminuye la expresión de proteínas epiteliales y se incrementan las mesenquimales. Por otro lado, se ha demostrado que la dehidroepiandrosterona (DHEA), el esteroide más abundante en el plasma humano, inhibe la migración de células de cáncer de mama; sin embargo, los mecanismos que rigen este proceso aún no se han determinado. En este trabajo se evaluó el efecto de la DHEA en la expresión de algunas proteínas involucradas en la TEM, como la E-caderina (epitelial), la N-caderina y la vimentina (mesenquimales) en las células de cáncer de mama MDA-MB-231 (fenotipo mesenquimal, invasivas y metastásicas) y MCF-7 (fenotipo epitelial, no invasivas, no metastásicas) mediante el uso de inmunoanálisis e inmunofluorescencia. También se evaluó el efecto de la DHEA en el crecimiento de tumores de células MDA-MB-231 en un modelo de xenotransplante in vivo con ratones nu-/nu-. Nuestros resultados mostraron que la DHEA aumentó la expresión de la E-caderina y disminuyó la de la N-caderina y la vimentina en las células MDA-MB-231; sin embargo, en las células MCF-7 no tuvo ningún efecto, lo que sugiere que la DHEA revierte el fenotipo mesenquimal, pero no afecta al epitelial. En el modelo in vivo se observó una disminución en el tamaño de los tumores cuando la DHEA se administró una semana antes y al mismo tiempo en que se realizó la inoculación con las células de mama. En conclusión, la DHEA podría ser útil como un agente en el tratamiento contra el cáncer de mama que presenta un fenotipo mesenquimal y metastásico.