[Aerobiological study in Lima, Perú. ¿Tipuana-Tipu, perhaps a new allergen?] / Estudio aerobiológico en Lima, Perú. ¿Tipuana-Tipu, tal vez un nuevo alérgeno?

OBJECTIVE: To report the Tipuana tipu pollen as a new allergen capable of triggering allergic symptoms. METHODS: The pollen counts were made according to standardized technique with a Burkard seven days following the European Aerobiology Society´s Network Group recommendations.1 The trap was installed on the roof of Clinica SANNA, El Golf, San Isidro, which is 20 m high, 12°5'54"S 77°3'6"W in the west-south of the Lima urban area. The sampling period was performed from September 2020 to October 2021. Collection of Tipuana tipu pollens and Preparation of Tipuana tipu pollen extracts 1:20 w/v was done using a previously described method.2 We carried out systematic skin prick testing with Tipuana tipu pollen extract and other aeroallergens (Dermatophagoides pteronyssinus, Dermatophagoides farinae, Blomia tropicalis), molds (Cladosporium herbarum, Alternaria alternata, Aspergillus fumigatus, Penicillium notatum), cat and dog danders, Periplaneta americana, grass six mix, weed mix (Inmunotek, Spain) on 80 patients (18 to 50 years old) seen in our allergy center, they suffering from november to january rhinitis and/or conjunctivitis symptoms. The majority living near avenues and large green areas, where Tipuana trees grew. RESULTS: We found a total of 952 grains/m3 of Tipuana tipu pollen between November 2020 to january 2021, with the maximum concentration of 37 grains/m3 on December 10th. We also found other airborne pollen Types: Poaceae, Myrtaceae, Compositae and Betulaceae. 14/80 patients (17,5%) showed positive skin prick test only to Tipuana tipu extract. Most of the patients with positive tests to Tipuana extract presented symptoms of rhinoconjunctivitis during the Tipuana pollination period. Four patients showed positive skin prick test to Tipuana tipu and grass 6 mix extracts, most of the rest of our patients were sensitized to dust mites' extracts (Dermatophagoides pteronyssinus). CONCLUSIONS: The west-south population of Lima urban city is exposed to Tipuana tipu pollen. We do not foud previous publications about Tipuana tipu allergy. Almost 18% of the patients tested in our sample were mono-sensitized to this pollen. The results of this study should be compared with data from the forthcoming years, to identify seasonal and annual fluctuations, extend the traps to other locations in Lima, and of course try to standardize and improve the Tipuana tipu pollen extract.

OBJETIVO: Reportar al polen de Tipuana tipu como un nuevo alérgeno capaz de desencadenar síntomas alérgicos. MÉTODOS: Los conteos de polen se realizaron según la técnica estandarizada con un equipo colector tipo Hirst, Burkard spore trap for seven days, siguiendo las recomendaciones del grupo de la Red Europea de Sociedades de Aerobiología1. El equipo se instaló en la azotea de la Clínica SANNA El Golf, San Isidro, a 20 m de altura desde el nivel del suelo, 12°5'54"S 77°3'6"O en la zona suroeste del área urbana de Lima. El periodo de captación se llevó a cabo entre septiembre de 2020 y octubre de 2021. La recolección de granos de polen de Tipuana tipu, y la preparación del extracto alergénico (peso/volumen) 1:20 p/v, se realizó usando metodología previamente descrita2. Se realizaron estudios de pruebas cutáneas (skin prick test), en 80 pacientes (entre 18 y 50 años), con sintomatología de rinoconjuntivitis; referían, además, mayor intensidad de sus síntomas entre noviembre y enero. La mayoría de pacientes dijeron vivir cerca a avenidas y parques donde había árboles de Tipuana tipu. Fueron evaluados en el servicio de Alergología de la Clínica SANNA, El Golf, San Isidro. Se aplicaron extractos de polen de Tipuana tipu, y otros aeroalérgenos como ácaros del polvo (Dermatophagoides pteronyssinus, Dermatophagoides farinae, Blomia tropicalis), hongos ambientales (Cladosporium herbarum, Alternaria alternata, Aspergillus fumigatus, Penicillium notatum), epitelios de gato y perro, Periplaneta americana, mezclas de seis gramíneas, mezclas de malezas (Inmunotek, España). RESULTADOS: Encontramos un total de 952 granos/m3 de polen de Tipuana tipu entre noviembre de 2020 y enero de 2021; con la máxima concentración de 37 granos/m3 el 10 de diciembre. También identificamos otras familias polínicas: Poaceae, Myrtaceae, Compositae y Betulaceae. 14/80 pacientes (el 17,5%), resultaron positivos solo al extracto de Tipuana tipu, en el skin prick test. La mayoría de los pacientes con resultado positivo al extracto de Tipuana tipu referían síntomas de rinoconjuntivitis durante el periodo de polinización de los árboles de Tipuana. Cuatro pacientes tuvieron positividad al extracto de Tipuana tipu, y al extracto en mezcla de seis gramíneas; la mayoría del resto de pacientes mostraron sensibilidad a ácaros del polvo doméstico (Dermatophagoides pteronyssinus). CONCLUSIONES: Los habitantes de la zona suroeste de la ciudad urbana de Lima están expuestos al polen de Tipuana tipu. No hemos encontrado publicaciones previas sobre alergia a este tipo de polen. Casi un 18% de pacientes estudiados en nuestra muestra, estuvieron monosensibilizados al extracto del polen de Tipuana tipu. Los resultados de este estudio deberían ampliarse y ser comparados con data en los años siguientes, identificar fluctuaciones estacionales y anuales, extender los captadores a otras locaciones en Lima, y por supuesto, intentar estandarizar y mejorar el extracto del polen de Tipuana Tipu.

Predatory Arthropods Associated with the Invasive Tipu Psyllid, Platycorypha nigrivirga, in Southern Spain.

Platycorypha nigrivirga Burckhardt (Hemiptera: Psyllidae) is a neotropical invasive species strictly associated with the tipu tree, Tipuana tipu (Benth.) Kuntze (Fabaceae: Papilionoideae). This psyllid has rapidly spread to several temperate areas of Spain and Portugal causing considerable problems in urban landscapes. The aim of this study was to determine the arthropod predator complex of this exotic insect and report the possibility of its biological control. Three urban green areas were surveyed in southern Spain during 2018 and 2019. Platycorypha nigrivirga populations increased during the spring months and reached a maximum level between late May and mid-June, declining greatly during the summer. A large complex of generalist predator species was found to exert a certain natural control on the pest, belonging to Anthocoridae (68.53%), Coccinellidae (18.39%), Chrysopidae (5.67%), Miridae (4.39%) and Araneae (3.02%). Anthocoris nemoralis (Fabricius) (Hemiptera: Anthocoridae) was the most abundant predatory species, followed by Orius laevigatus (Fieber) (Hemiptera: Anthocoridae) and Scymnus laetificus Weise (Coleoptera: Coccinellidae). High levels of abundance of anthocorids coincided with the highest abundance of the pest, showing a significant relationship with the psyllid density. Anthocoris nemoralis seems to be a promising candidate to control P. nigrivirga in the urban green areas of southern Spain, but more studies are needed to define the optimum management strategies.

Intra-annual oxygen isotopes in the tree rings record precipitation extremes and water reservoir levels in the Metropolitan Area of São Paulo, Brazil.

The impacts of climate change on precipitation and the growing demand for water have increased the water risks worldwide. Water scarcity is one of the main challenges of the 21st century, and the assessment of water risks is only possible from spatially distributed records of historical climate and levels of water reservoirs. One potential method to assess water supply is the reconstruction of oxygen isotopes in rainfall. We here investigated the use of tree-ring stable isotopes in urban trees to assess spatial/temporal variation in precipitation and level of water reservoirs. We analyzed the intra-annual variation of δ13C and δ18O in the tree rings of Tipuana tipu trees from northern and southern Metropolitan Area of São Paulo (MASP), Brazil. While variation in δ13C indicates low leaf-level enrichments from evapotranspiration, δ18O variation clearly reflects precipitation extremes. Tree-ring δ18O was highest during the 2014 drought, associated with the lowest historical reservoir levels in the city. The δ18O values from the middle of the tree rings have a strong association with the mid-summer precipitation (r = -0.71), similar to the association between the volume of precipitation and its δ18O signature (r = -0.76). These consistent results allowed us to test the association between tree-ring δ18O and water-level of the main reservoirs that supply the MASP. We observed a strong association between intra-annual tree-ring δ18O and the water-level of reservoirs in the northern and southern MASP (r = -0.94, r = -0.90, respectively). These results point to the potential use of high-resolution tree-ring stable isotopes to put precipitation extremes, and water supply, in a historical perspective assisting public policies related to water risks and climate change. The ability to record precipitation extremes, and previously reported capacity to record air pollution, place Tipuana tipu in a prominent position as a reliable environmental monitor for urban locations.