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La tromboembolia pulmonar (TEP) sigue siendo un desafío importante para la medicina clínica, pues en unos casos puede llevar a una muerte rápida, mientras que en otros no presenta sintomatología y pude pasar desapercibida, además, es la tercera causa de muerte de origen cardiovascular. Esta enfermedad es ocasionada por la migración de un coágulo, proveniente principalmente de miembros pélvicos, que se aloja en una arteria pulmonar ocasionando su obstrucción parcial o completa. El propósito de esta revisión es describir la epidemiología, factores de riesgo y fisiopatología de la TEP y, analizar el diagnóstico y cuadro clínico de la enfermedad, así como su tratamiento y seguimiento.

Introduction: Ovarian cancer is one of the most lethal diseases in the female population worldwide. Indeed, the survival rate of ovarian cancer is very low when diagnosed lately and the success rate of current chemotherapy regimens is not very efficient. One of the main chemotherapy treatment regimens is the use of platinum drugs, specifically carboplatin (CBDCA). Nevertheless, one of the main reasons for this low success rate is the acquired chemoresistance of these cancers during their progression. The mechanisms responsible for this chemoresistance are numerous, including efflux pumps, repair mechanisms, survival pathways and tumor suppressors. In the last decade, lncRNAs have been identified as a new element responsible in the regulation of chemoresistant phenotype since they have been linked to multiple biological processes and acting in combination with other mechanism involved in chemoresistant. However, little is known about their role in carboplatin resistance in OC. This study seeks to characterize the effect of lncRNA expression on the chemoresistant phenotype and its correlation with the hyperactivation of drug efflux pumps. Materials and Methods: Ovarian cancer cell lines A2780-R-CBDCA, A2780-P, UCI-101, OVCAR3 and SKOV3 were used in this study. Chemosensitivity to carboplatin was measured by MTT Assay in 96-well plates after 24, 48 and 72h treatment for determinating IC50 values. Relative expression of MNX1-AS1 associated with CBDCA-resistant phenotype and efflux pumps were evaluated by qRT-PCR. Results: It was observed that A2780-R-CBDCA, SKOV3 and OVCAR3 cell lines presented the highest resistance indices in contrast to UCI-101 and A2780-P, which turned out to be highly sensitive to treatment with CBDCA. The relative expression of MNX1-AS1 was found elevated in those lines that presented higher levels of resistance to the drug, while in those more sensitive to treatment, the expression of MNX1-AS1 was found to be decreased. On the other hand, the expression levels of the ABCB1 and ABCC1 efflux pumps showed contradictory results in relation to their expression compared to the resistance index shown in each cell line. Mainly, it could be observed that ABCB1 presented a decreased expression in A2780-R-CBDCA, while ABCC1 was found to be increased in the same line. Conclusion: Our results indicate that the expression of MNX1-AS1 could contribute to the development or maintenance of a chemoresistant phenotype to platinum drugs. Meanwhile, the effect of the expression of MNX1-AS1 on the efflux pumps is not yet possible to relate as a modulator of its hyperactivation. However, their potential participation in this mechanism is not ruled out and new analyzes are necessary to rule out this possible relationship. Citation Format: Kurt Buchegger Mena, Tamara Viscarra Alvarez, Daniela León Garrido, Ramón Silva Pezoa, Carmen Ili Gangas, Sindy Cabarca Barreto, Marcela Berrios Flores, Jorge Sapunar Zenteno, Priscilla Brebi Mieville. MNX1-AS1 expression is positively correlates with expression of drug efflux pumps in ovarian cancer. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 3897.

Introduction: Photodynamic therapy (PDT) is a treatment for non melanoma skin cancer. PDT kills cells through reactive oxygen species (ROS), produced by interaction between cellular O2 and an excited photosensitizer (PS) by a specific light. One of the most used PS in dermatology is Protoporphyrin IX (PpIX) and its precursor methyl aminolevulinate (MAL). MAL enters into cells and is converted to PpIX by enzymes of the heme group synthesis pathway. The insertion of ferrous iron into PpIX forms a heme molecule, which has no PS action. A previous study shows that efficacy of PDT, in resistant cells, can be improved by addition of epigallocatechin gallate (EGCG), a green tea polyphenol. Therefore, the aim of this work is to evaluate the rol of EGCG on PPIX synthesis. Material and methods: It was used a A-431 cell line from skin squamous cell carcinoma. The EC50 of EGCG was determined by MTT assay after 24 hours. Clonogenic assay was carried out using EGCG 10, 20 and 40 μM, for 4 and 24 hours of incubation. To evaluate PpIX and ROS, A-431 cells were exposed to EGCG (10, 20, 40 μM) with or without MAL 2 mM. After 4 hours, some plates were irradiated with red light to generate ROS. PpIX and ROS were detected by flow cytometry. Gene expression of enzymes of heme synthesis was analyzed by RT-qPCR. Intracellular iron was measured using a commercial kit. Results: EC50 determined a concentration of 50 μM of EGCG at 24 hours. EGCG concentrations from 10 μM reduced cell clonogenic capacity, even with only 4 hours of incubation. A-431 cells show PDT resistance with MAL 2 mM and a fluence of 4 J/cm2. The addition of EGCG to MAL-PDT showed a decrement of cell viability with an increase of PpIX and ROS. Besides, incubation with EGCG for 4 hours, triggered an increment of HMBS enzyme and decrease of FECH. In addition, EGCG reduced intracellular iron concentrations. Conclusion: These findings show that EGCG has a PDT enhancing effect, decreasing intracellular iron levels and modulating gene expression of heme synthesis enzymes, which are directly related with high levels of PpIX production and ROS levels, causing the death of resistant cells.Acknowledgements: Postdoctoral FONDECYT Nº 3210618, IDeA I+D FONDEF ID21I10027 Citation Format: Daniela León, Álvaro Gutiérrez, Helga Weber, Ramón Silva, María Elena Reyes, Tamara Viscarra, Kurt Buchegger, Carmen Ili, Priscilla Brebi. PpIX synthesis increases PDT resistant cells due to the modulating effect of EGCG on the heme synthesis pathway [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 2845.

COVID-19 pandemic confinement caused changes in families and children’s routines worldwide. Studies conducted at the beginning of the pandemic have examined the harmful effects of these changes on mental health, including sleep disturbances. As sleep is essential for optimal childhood development, this study was designed to determine preschool-aged (3–6 years old) children’s sleep parameters and mental well-being during the COVID-19 pandemic in Mexico. Using a cross-sectional design, a survey was applied to parents of preschool children, inquiring about their children’s confinement status, routine changes, and electronics use. The parents responded to the Children’s Sleep Habits Questionnaire and the Strengths and Difficulties Questionnaire to assess children’s sleep and mental well-being. To provide objective sleep data, the children wore wrist actigraphy for seven days. Fifty-one participants completed the assessment. The children’s mean age was 5.2 years, and the prevalence of sleep disturbances was 68.6%. The use of electronic tablets in the bedroom near bedtime and symptoms of mental health deterioration (i.e., emotional distress and behavioral difficulties) were associated with sleep disturbances and their severity. The COVID-19 pandemic’s confinement-related routine changes greatly impacted preschool children’s sleep and well-being. We recommend establishing age-tailored interventions to manage children at higher risk.

Con la aparición de SARS-CoV-2 el mundo ha entrado en estado de emergencia y se ha puesto en cuarentena desde finales del 2019. SARS-CoV-2 varía su periodo de incubación, grado de contagio y letalidad de acuerdo a diversos índices de varios países. Según estudios de secuenciación se ha descubierto que es un virus que mutó de la cepa de un virus endémico de ciertos murciélagos, este se adhiere con facilidad a los receptores de ECA-II, los cuales se expresan de manera amplia a nivel de la mucosa del sistema respiratorio. Su principal forma de transmisión es a través de gotitas respiratorias que se producen cuando hablamos, tosemos o estornudamos. La mayoría de casos son asintomáticos, lo que dificulta el diagnóstico y el control de la tasa de contagios. En aquellos casos sintomáticos se puede presentar un cuadro gripal con síntomas generales, neumonía o síndrome de distrés respiratorio agudo, Para su diagnóstico nos podemos auxiliar de la prueba de PCR, radiografía torácica y en algunos casos TAC como principales herramientas. Actualmente no existe ningún fármaco específico para la enfermedad, pero existen tratamientos auxiliares y de soporte que han mostrado su eficacia en algunos pacientes. Se está a la espera de una vacuna.

RESUMEN Etiella zinckenella es una plaga cosmopolita de distribución mundial que ataca principalmente a especies de la familia Fabaceae, considerándose la soya como su principal hospedero. La larva del insecto ingresa a las vainas y se alimenta de las semillas, produciendo fecas que se acumulan y generan la pérdida de las semillas. En Chile, se ha reportado la presencia de E. zinckenella en la Región Metropolitana, sin especificar el hospedero en el cual se detectó. Durante el período febrero-marzo de 2019, se prospectaron poblaciones de Alstroemeria spp. nativas (A. angustifolia, A. cummingiana y A. marticorenae) en el sector de Rodelillo Alto, Viña del Mar, para la colecta de frutos con la finalidad de identificar el agente causal de perforaciones detectadas en éstos. En las cápsulas recolectadas se registró la presencia de larvas de E. zinckenella alimentándose de las semillas. La determinación del insecto a nivel de especie se realizó con un análisis morfológico de las larvas, ratificado a través de la observación de genitalias de hembras y machos adultos obtenidos en crianza. En este estudio se documenta la primera detección e identificación de E. zinckenella en poblaciones de Alstroemerias nativas en Chile.

Simple Summary Cancer is the second leading cause of death in humans, and in 2020, 9.8 million cancer-related deaths were reported worldwide. In the last 20 years, it has become apparent that small vesicles released by cancer cells, referred to as extracellular vesicles (EVs), are key players in cell–cell communication in the tumor environment, and as a consequence, research in this area has increased dramatically. This review summarizes the recent advances in our understanding of how EVs serve as mediators of communication between cancer cells and with their surroundings in order to promote the acquisition of specific characteristics that permit their aberrant behavior. In addition, we dwell on how EVs aid in the development of drug resistance, which is a frequent cause of treatment failure in chemotherapy. Finally, we discuss an exciting new area of research that envisions harnessing the unique characteristics of EVs for therapeutic and diagnostic purposes (theranostics). Taken together, the available literature suggests that advances in our understanding of EV biology in the next decades will likely be critical to achieving more effective treatments in cancer patients. Abstract Cancer remains a leading cause of death worldwide despite decades of intense efforts to understand the molecular underpinnings of the disease. To date, much of the focus in research has been on the cancer cells themselves and how they acquire specific traits during disease development and progression. However, these cells are known to secrete large numbers of extracellular vesicles (EVs), which are now becoming recognized as key players in cancer. EVs contain a large number of different molecules, including but not limited to proteins, mRNAs, and miRNAs, and they are actively secreted by many different cell types. In the last two decades, a considerable body of evidence has become available indicating that EVs play a very active role in cell communication. Cancer cells are heterogeneous, and recent evidence reveals that cancer cell-derived EV cargos can change the behavior of target cells. For instance, more aggressive cancer cells can transfer their “traits” to less aggressive cancer cells and convert them into more malignant tumor cells or, alternatively, eliminate those cells in a process referred to as “cell competition”. This review discusses how EVs participate in the multistep acquisition of specific traits developed by tumor cells, which are referred to as “the hallmarks of cancer” defined by Hanahan and Weinberg. Moreover, as will be discussed, EVs play an important role in drug resistance, and these more recent advances may explain, at least in part, why pharmacological therapies are often ineffective. Finally, we discuss literature proposing the use of EVs for therapeutic and prognostic purposes in cancer.

Simple Summary The Epstein–Barr virus (EBV) has been implicated in several human neoplastic diseases. The EBV-1 can transform B cells into LCL more efficiently than EBV-2, and EBV-2 preferentially infects T-cell lymphocytes. The EBNA3A oncoprotein has an essential role in B-cell transformation. The six peptide motifs called nuclear localization signals (NLSs) from EBNA3A ensure nucleocytoplasmic protein trafficking. Multiple NLSs have been suggested to enhance EBNA3 function or different specificities to different cell types; however, a comprehensive assessment of their genetic variability has not been addressed. Our objective was to study the NLSs’ variability and their relationship with EBV types. Based on a comprehensive analysis of over a thousand EBNA3A sequences from different clinical manifestations and geographic locations, we found that EBNA3A from EBV-2 has two of the six NLSs altered, and genetic patterns in the NLSs are associated with EBV-1 and EBV-2. Abstract The Epstein–Barr virus (EBV) is a globally dispersed pathogen involved in several human cancers of B-cell and non-B-cell origin. EBV has been classified into EBV-1 and EBV-2, which have differences in their transformative ability. EBV-1 can transform B-cells into LCL more efficiently than EBV-2, and EBV-2 preferentially infects T-cell lymphocytes. The EBNA3A oncoprotein is a transcriptional regulator of virus and host cell genes, and is required in order to transform B-cells. EBNA3A has six peptide motifs called nuclear localization signals (NLSs) that ensure nucleocytoplasmic protein trafficking. The presence of multiple NLSs has been suggested to enhance EBNA3 function or different specificities in different cell types. However, studies about the NLS variability associated with EBV types are scarce. Based on a systematic sequence analysis considering more than a thousand EBNA3A sequences of EBV from different human clinical manifestations and geographic locations, we found differences in NLSs’ nucleotide structures among EBV types. Compared with the EBNA3A EBV-1, EBNA3A EBV-2 has two of the six NLSs altered, and these mutations were possibly acquired by recombination. These genetic patterns in the NLSs associated with EBV-1 and EBV-2 provide new information about the traits of EBNA3A in EBV biology.

Photodynamic therapy (PDT) has been used to treat certain types of non-melanoma skin cancer with promising results. However, some skin lesions have not fully responded to this treatment, suggesting a potential PDT-resistant phenotype. Therefore, novel therapeutic alternatives must be identified that improve PDT in resistant skin cancer. In this study, we analyzed the cell viability, intracellular protoporphyrin IX (PpIX) content and subcellular localization, proliferation profile, cell death, reactive oxygen species (ROS) detection and relative gene expression in PDT-resistant HSC-1 cells. PDT-resistant HSC-1 cells show a low quantity of protoporphyrin IX and low levels of ROS, and thus a low rate of death cell. Furthermore, the resistant phenotype showed a downregulation of HSPB1, SLC15A2, FECH, SOD2 and an upregulation of HMBS and BIRC5 genes. On the other hand, epigallocatechin gallate catechin enhanced the MAL-PDT effect, increasing levels of protoporphyrin IX and ROS, and killing 100% of resistant cells. The resistant MAL-PDT model of skin cancer squamous cells (HSC-1) is a reliable and useful tool to understand PDT cytotoxicity and cellular response. These resistant cells were successfully sensitized with epigallocatechin gallate catechin. The in vitro epigallocatechin gallate catechin effect as an enhancer of MAL-PDT in resistant cells is promising in the treatment of difficult skin cancer lesions.

Few studies have focused on the specific subtype of gamblers who present lotteries as their main gambling problem. This study aimed to explore empirical subgroups of treatment-seeking patients who endorsed lotteries as their preferred form of gambling. The sample included n = 342 patients who were included in two-step cluster analysis procedures using sociodemographic and clinical measures as indicator variables. Three clusters were identified: (a) Cluster 1 (labeled as “severely impaired young men”, n = 108, 31.6%) included mainly single young men that were employed, with short disorder duration, high gambling severity and high levels of comorbid psychopathology; (b) Cluster 2 (labeled as “moderate severity and highly functional”, n = 120, 35.1%) included patients that were middle-aged, highly educated, married, employed, with high socioeconomic position indexes and functional personality traits; and (c) Cluster 3 (labeled as “older, moderately impaired patients”, n = 114, 33.3%) included older patients, the highest percentage of separated or divorced subjects, high unemployment, low socioeconomic status and low levels of education. This study indicates that gambling disorder profiles characterized by lotteries as a preferred form of gambling constitute a heterogeneous group in which distinct, empirically based phenotypes can be identified. These factors should be taken into account for the development of reliable assessment instruments and for the design of effective prevention and treatment programs.

El presente artículo pretende comparar las lecturas filosóficas que hacen Deleuze y Descombes de la Recherche, con el fin de mostrar las semejanzas y diferencias metódicas. Nos interesa mostrar el cambio de enfoque y del sentido de ‘lectura filosófica’ de una novela. Deleuze hace un estudio sistemático-taxonómico centrado en los tipos de signos y su aprendizaje. Descombes se centra en la forma novelesca, concretamente, en la técnica y pensamiento del novelista como creador.

The plural forms of peace have existed throughout history; they have been expressed in local, particular and especially imperfect ways which have allowed life itself to thrive. However, forms of violence have hidden them under the premise of fear devices that break subjectivities and identities with an obvious outcome of exerting hegemonic power over others. Among conflict of territories that have been historically marked by sustained impoverishment in a violent way, there are groups that deploy actions recognized as pacifists mediations and allow the emergence of “other forms” of inhabiting territories, in which life is enhanced in its most generic way and configures forms of political action as re-existence possibilities in the face of opacities of hegemonic forms which invalidate inhabitants. This document approaches the question about local mobilization forms centered in pacifist and nonviolent practices for the configuration of inhabitation forms and the realities that need to be transform.

Globally, human papillomavirus (HPV) is the most frequent sexually transmitted infection (STI) and it affects men and women equally. In men, HPV has been mainly associated with skin lesions like ano-genital warts and intraepithelial neoplasia of penis and anus in recent years. HPV prevalence in men varies extremely due to kind of sample and detection techniques. The most widely used samples to study HPV in men are: penile shaft, glans, prepuce, coronal sulcus, urine and semen, and its detection is usually performed with techniques like reverse line blot (RLB) and hybrid capture (HC). Given that the highest infection rates are in Africa and Latin America, the aim of this review is to describe the pathogenesis of HPV and its main detection techniques in men.

Ethanol (EtOH) enhances glycinergic currents in the central nervous system (CNS). Because evidence for an interaction between the α1 subunit of the glycine receptor (α1GlyR) and the G protein Gβγ subunit exists in vitro and because cAMP levels are known to increase in response to EtOH, we wanted to investigate the interaction between Gβγ and α1GlyR in response to EtOH treatment in HEK293 cells and to explore the possible sites of interaction between EtOH and the Gαs subunit. His pull-down assays in GlyR-His6-transfected HEK293 cells incubated with ethanol or propofol revealed that only EtOH treatment increased the binding of Gβγ heterodimers to α1GlyR. Using molecular modelling (protein structure prediction), was modelled the hGαs protein for the first time and validated this model by site-directed mutagenesis. By molecular docking, we identified some potential regions of interaction between hGαs and EtOH that are located on the SIII and SI regions of the Gαs. Therefore, we conclude that ethanol increases the interaction between α1GlyR and Gβγ in HEK293 cells, an effect that might be attributed to the interaction between EtOH and hGαs, which consequently stimulates hGαs.

Los bosques andinos de la Cordillera Oriental son prioridad de conservación en Colombia, dado el estado vulnerable de especies como Quercus humboldtii (Fagaceae) que habita en estos ecosistemas. La apicultura se considera una alternativa de uso compatible con la conservación de los bosques andinos, sin embargo se conoce muy poco sobre cómo contribuye la flora de estos ecosistemas a la producción de miel y polen apícola. Específicamente se analiza la contribución de los bosques andinos a la producción de polen apícola, dado su potencial productivo en la zona y la importancia comercial de este producto. Para tal fin se realizaron análisis palinológicos de 25 muestras de polen apícola, provenientes de apiarios que tienen bosques andinos en su área de influencia, ubicados en los departamentos de Cundinamarca, Boyacá y Santander. Se encontró que Q. humboldtii es una fuente importante de polen con alto potencial para la producción de polen apícola monofloral. Además, las abejas recolectan polen de plantas asociadas a los bosques andinos como Weinmannia tomentosa, Viburnum spp. y Morella spp. El polen apícola puede convertirse en un incentivo para llevar a cabo prácticas de conservación del bosque dentro del manejo apícola. The Andean forests of the Eastern Andean high-lands of Colombia have a high conservation priority given the vulnerable condition of species such as Quercus humboldtii (Fagaceae) that inhabit these ecosystems. Beekeeping is regarded as an alternative activity that could play a role in the conservation of Andean forests, but little is known about how the floras of these ecosystems contribute to honey and bee pollen production. We analyzed the contribution of Andean forests to bee pollen production, given the productive potential and commercial importance of this product. Pollen analyses were performed on 25 samples from apiaries near Andean forests located in the states of Cundinamarca, Boyacá and Santander. We found that Q. humboldtii is an important source of pollen with high potential for monofloral bee pollen production. In addition, bees collect pollen from other Andean forests species such as Weinmannia tomentosa, Viburnum spp. and Morella spp. Utilization of bee pollen could lead to incentives to carry out forest conservation practices through beekeeping management.

Introduction: Squamous skin cancer is one of the most common neoplasia worldwide and may be preceded by Bowen's disease (BD) and Actinic Keratosis (AK). These preneoplastic lesions can be treated with photodynamic therapy (PDT). PDT causes cell death mainly by reactive oxygen species (ROS) produced through a combination of O2, a photosensitizer and light. BD and AK have well overcomes after PDT. However, high recurrence rates of some lesions have been reported. Objective: To generate resistant cells to PDT as an in vitro model for future studies. Methodology: HSC-1 cells from human squamous cell cancer (SCC) of skin were used. Cells were treated with a total of 16 cycles of PDT. Every PDT cycle was carried out incubating cells with methyl aminolevulinate (MAL), as a protoporphyrin IX (PpIX) precursor, for 4 hours in the dark. Then, cells were irradiated with red light (630 nm). The light fluence used for the four first cycles was 1 J/cm2, for subsequent cycles light fluence increased to 2, 3 and 4 J/cm2. Cell viability was evaluated 1 and 24 hours after PDT by flow cytometry and MTT assay respectively. Intracellular PpIX was detected by flow cytometry and the PpIX content was quantified using a standard curve. By flow cytometry using a CM-H2DCFDA probe intracellular ROS was detected. Results: After 24 hours of PDT (4 J/cm2), viability in parental HSC-1 cells was 5%, meanwhile in resistant cells was 70% (P < 0.05). On the other hand, 88% of parental cells produced PpIX (40 ng/mg protein) and 18% of resistant cells produced PpIX (17 ng/mg protein) (P < 0.05). No significant differences were found in ROS detection in both parental and resistant cells. Conclusion: The results indicate that it was possible to obtain HSC-1 cells two-fold resistant to PDT compared to their parental cells. Acknowledgments: Financial support by CONICYT. CONICYT-PCHA/Doctorado Nacional/2012-21120665, CORFO 09CN14-5960, Corfo N°12IDL2-18157, FONDECYT N° 11150802, FONDECYT N°11150622. Citation Format: Daniela Leon, Ramon Silva, Natalia Inada, Cristina Kurachi, Carmen Gloria Ili, Priscilla Brebi, Juan Carlos Roa. Resistance to Photodynamic Therapy in Non-Melanoma Skin Cancer Cells. [abstract]. In: Proceedings of the AACR Precision Medicine Series: Cancer Cell Cycle - Tumor Progression and Therapeutic Response; Feb 28-Mar 2, 2016; Orlando, FL. Philadelphia (PA): AACR; Mol Cancer Res 2016;14(11_Suppl):Abstract nr B30.

The jungle is the habitat for millions of species. Not only does it play an important role in our economy in providing timber and non-timber products, but it also provides such environmental services as carbon sequestration and the conservation of biodiversity. For these reasons, it is important to guarantee the sustainable use of the Peruvian Amazon forest. Sustainability involves meeting present human needs without endangering the welfare of future generations; however, it does not imply failing to take advantage of the growth opportunities that the forest offers.Madre de Dios is a Peruvian department of enormous natural wealth, but lacking in infrastructure and with a poorly developed timber sector (which is the region’s most important source of economic activity). How do we explain the low impactthat the growth of the timber sector has had on the living conditions for people living in Madre de Dios? This study shows that insufficient infrastructure has been one of the main impediments to developing this cluster’s competitiveness. However, projects such as paving the Interoceanic Highway and the San Gabán hydroelectric connection will help drive this competitiveness. This is a necessary condition to generate profitability from sustainable exploitation of the jungle. Similarly, gains in competitiveness are important in generating positive externalities for the region., Los bosques son el hábitat de millones de especies de flora y fauna. Entre los servicios ambientales y sociales que proporcionan, están la conservación de la diversidad biológica, la captación del carbono para mitigar el cambio climático mundial y la conservación de suelos y aguas (FAO). Por ello, resulta de suma relevancia el aprovechamiento sostenible de los bosques de más de setenta millones de hectáreas en la Amazonía peruana. El término «sostenibilidad» implica satisfacer las necesidades de las generaciones presentes sin comprometer las necesidades de las generaciones futuras; sin embargo, ello no implica subaprovechar las oportunidades de crecimiento económico que los bosques brindan a los agentes pertenecientes a su entorno.En este contexto, se observa departamentos de la selva amazónica, como Madre de Dios (MdeD), con gran riqueza en recursos naturales pero con altos índices de pobreza en infraestructura y un desarrollo incipiente del sector forestal, una de sus principales actividades económicas. ¿Cómo explicar el reducido impacto que ha tenido el crecimiento del sector forestal sobre las condiciones de vida de la población? MdeD no ha sabido dirigir los ingresos provenientes del aprovechamiento del recurso hacia políticas públicas que generen los incentivos necesarios para promover una situación de competitividad que haga rentable el manejo sostenible del recurso.La coyuntura actual provee oportunidades para el desarrollo de un cluster forestal competitivo y articulado, que genere externalidades positivas para la región. Por ende, la presente investigación tiene como objetivo central analizar el grado de madurez del cluster forestal maderero de MdeD y evaluar sus posibilidades de crecimiento en la actual coyuntura. El estudio refleja que la carencia de infraestructura ha sido una de las principales limitaciones de la competitividad del sector; sin embargo, proyectos como la Carretera Interoceánica Sur (IOS) y la hidroeléctrica de San Gabán actuarían como una fuente importante de competitividad para algunos agentes del cluster.

Se presentan las descripciones morfológicas y fotografías de los granos de polen de 122 especies distribuidas en 54 familias, correspondientes a morfotipos encontrados en miel de Apis mellifera producida en la Sierra Nevada de Santa Marta. Se incluye información adicional sobre nombres comunes, presencia de nectarios, rangos de abundancia en la miel y observaciones ecológicas complementarias. Las familas que aportan el mayor número de especies son las siguientes: Asteraceae, Fabaceae, Malvaceae, Euphorbiaceae, Melastomataceae, Myrtaceae, Poaceae y Sapindaceae. Entre las especies nectaríferas predominantes en la miel se encuentran Austroeupatorium inulifolium, Critonia morifolia, Bursera simaruba, Croton hirtus (Croton spp.), Gliricidia sepium, Inga oerstediana, Adenaria floribunda, Heliocarpus americanus, Muntingia calabura, Rubus urticifolius (Rubus spp.), Coffea arabica y Vitis tiliifolia. Entre las especies no productoras de néctar aparecen como predominantes Astronium graveolens, Carludovica palmata, Begonia guaduensis (Begonia spp.), Trema micrantha, Hediosmum racemosum, Doliocarpus dentatus, Mimosa albida, Mimosa pudica, Poulsenia armata (Moraceae spp.), Piper aduncum (Piper spp.) y Cecropia peltata. Este trabajo se realizó con el fin de aportar una herramienta para los trabajos en melisopalinología que se vienen desarrollando en las regiones cafeteras de la Sierra Nevada de Santa Marta y otras zonas de Colombia. We present pollen grain morphological descriptions and photographies of 122 species distributed in 54 families, corresponding to morfotypes found in Apis mellifera honey produced in the Sierra Nevada de Santa Marta. Additional information about common names, presence of necteries, abundance range and complementary ecological observations is included. The families with the most number of species were Asteraceae, Fabaceae, Malvaceae, Euphorbiaceae, Melastomataceae, Myrtaceae, Poaceae and Sapindaceae. Preponderant nectar species were Austroeupatorium inulifolium, Critonia morifolia, Bursera simaruba, Croton hirtus (Croton spp), Gliricidia sepium, Inga oerstediana, Adenaria floribunda, Heliocarpus americanus, Muntingia calabura, Rubus urticifolius (Rubus spp.), Coffea arabica and Vitis tiliifolia. Major nectarless species were Astroniumgraveolens, Carludovica palmata, Begonia guaduensis (Begonia spp.), Trema micrantha, Hediosmum racemosum, Doliocarpus dentatus,Mimosa albida, Mimosa pudica, Poulsenia armata (Moraceaespp.), Piper aduncum (Piper spp.) and Cecropia peltata. This catalog was done with the aim of providing a work tool for melisopalynological analysis undertaken inthe Sierra Nevada de Santa Marta and other coffee-growing regions in Colombia.

RESUMEN El presente artículo señala los resultados de una investigación correspondiente a un estudio cualitativo-interpretativo, que describe los elementos comunes y diferenciadores en las trayectorias vitales de estudiantes de psicología, sociología y trabajo social, relacionados con su opción de formación profesional. Teniendo en consideración el papel desvalorizado de las disciplinas de las ciencias sociales en el contexto socioeconómico actual y la obtención de bajos salarios de estas profesiones en el campo laboral, se problematiza la idea de que aun así, sigue siendo de las áreas más demandadas por los estudiantes al momento de su ingreso a la educación superior, en ello radica la importancia de conocer los elementos en las trayectorias de vida de los estudiantes que inciden en su elección profesional al optar por el área de las ciencias sociales y por las diferentes profesiones en particular. Palabras Clave: Trayectorias de vida - Ciencias sociales - Formación profesional - Vocación profesional Trajetórias de vida e eleição profissional: elementos que influenciam a eleição profissional de estudantes de psicologia, sociologia e trabalho social RESUMO O presente artigo indica os resultados de uma investigação correspondente a um estudo cualitativo-interpretativo, que descreve os elementos comuns e diferenciadores nas trajetórias vitais de estudantes de psicologia, sociologia e trabalho social, relacionados com sua opção de formação profissional. Tendo em consideração o papel desvalorizado das disciplinas das ciências sociais no contexto socioeconômico atual e a obtenção dos baixos salários destas profissões no campo laboral, problematiza-se a ideia de que ainda assim, continuam sendo as disciplinas mais demandadas pelos estudantes ao momento de seu ingresso na educação superior. Nisto radica a importância de conhecer os elementos nas trajetórias de vida dos estudantes que incidem em sua eleição profissional ao optar pelo campo das ciências sociais e pelo as diferentes profissões em particular. Palavras Chave: Trajetórias de vida - Ciências sociais - Formação profissional - Vocação profissional Trajectories of life and professional training choice: influential elements in professional training choice of psychology, sociology and social work students ABSTRACT This article outlines the results of a qualitative-interpretive study, which describes the commonalities and differentiators in the life trajectories of students of psychology, sociology and social work related to their professional training options. Considering the devalued role of social science disciplines in the current economic context and low wages of related-field professions in the workplace, it is argued that they still remain the most preferred options among students at the time of starting their higher education studies. Hence it is critical to identify the elements in the life trajectories of students that influence their professional training choice of the social sciences disciplines and professions. Keywords: Trajectories of Life - Social Sciences - Professional Training - Professional Vocation