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2.
Sci Total Environ ; 806(Pt 1): 150505, 2022 Feb 01.
Article En | MEDLINE | ID: mdl-34844323

Climate-induced changes in precipitation and land-use intensification affect the discharge of streams worldwide, which, together with eutrophication and loss of riparian canopy, can affect periphyton biomass and composition, and therefore, ultimately the stream functioning. We investigated the responses of periphyton biomass and life-forms (i.e., high profile, low profile and motile) to these changes applying an experimental approach by modulating nutrients (nutrient diffusion substrates enriched with 0.5 M NH4NO3 + 0.031 M KH2PO4 and without nutrient enrichment) and light availability (50% shade and full light) along a gradient in discharge ranging from 0.46 to 3.89 L/s (0.7 to 6.5 cm/s) in twelve large-sized (12- m long) outdoor flumes resembling lowland streams. We also analysed the potential effects of other environmental variables including macroinvertebrates on the responses of periphyton to discharge, nutrients, and light. Light and nutrient availability drastically affected periphyton biomass and composition responses to discharge. Periphyton biomass decreased with increasing discharge when shaded but this did not happen when exposed to full light. Under full light conditions, nutrient enrichment mediated an increase in the periphyton biomass with increasing discharge, possibly reflecting an increased metabolism, but this did not happen under non-enriched conditions. Enrichment further affected the compositional responses of periphyton to discharge, with an increase in the biomass of motile, fast-growing, small-sized flagellated at low discharge conditions, and mitigating a loss of high profile periphyton under higher discharges. Light did not affect periphyton composition, and the abundance or feeding-group composition of the macroinvertebrates did not affect biomass or composition of the periphyton either. Our results suggest that nutrient enrichment and light play an important synergistic role in the responses of the periphyton biomass and composition to discharge and emphasize the relevance of riparian canopy conservation and eutrophication control to avoid periphyton growth under increased discharge scenarios in small lowland streams.


Periphyton , Biomass , Ecosystem , Eutrophication , Nutrients , Rivers
3.
Sci Total Environ ; 797: 148998, 2021 Nov 25.
Article En | MEDLINE | ID: mdl-34346382

Warming, eutrophication, and increased omnivory by small-sized fish are global change processes that induce major effects on the food web structure and primary producers of shallow lakes. Despite the key relevance of phytoplankton and periphyton in freshwaters, the combined and potential synergistic effects of fish omnivory, warming and eutrophication, especially on periphyton, remains little addressed, particularly for subtropical shallow lakes. We experimentally tested the food web effects on phytoplankton and periphyton induced by small visually feeding omnivorous fish (Rhodeus ocellatus), high nutrient enrichment and warming (+4.5 °C) in thirty-two 1000 L-mesocosms simulating littoral conditions of subtropical shallow lakes. We aimed at analysing the mechanisms and responses of periphyton and phytoplankton to these experimental factors. All mesocosms included the submerged macrophytes Vallisneria denseserrulata and Potamogeton lucens and artificial plants at 50% plant volume inhabited, plankton and macroinvertebrates. Small-sized visually feeding omnivorous fish enhanced phytoplankton dominance and periphyton loss. These changes coincided with a decrease in zooplankton biomass and a diversity loss of both zooplankton and macroinvertebrates as well as an increase in snail abundance. Fish presence led to a collapse of cladocerans, thereby releasing the grazing pressure on phytoplankton, and predator and collector macroinvertebrates were replaced with small snails (Radix peregra < 0.5 cm) resulting in enhanced grazing on periphyton. Eutrophication reinforced the fish effects, while warming had weak or no effects. Our results indicate that omnivory by small-sized visually feeding fish may induce stronger effects on the food webs of shallow lakes, towards phytoplankton-dominated states, than the combined effect of nutrient enrichment and warming under the present experimental conditions.


Food Chain , Lakes , Animals , Biomass , Eutrophication , Phytoplankton , Zooplankton
4.
Int. j. morphol ; 37(4): 1305-1309, Dec. 2019. tab
Article Es | LILACS | ID: biblio-1040129

En la enseñanza de la anatomía, el uso de los epónimos es cada vez más escaso, sin embargo su uso aún es evidente incluso en la literatura actualizada, en este caso el uso del epónimo se acompaña generalmente del término correcto según la Terminología Anatómica Internacional (TAI). El denominado "Tubérculo de Gerdy" (TG) es un epónimo ampliamente usado en la literatura y la comunidad científica para denominar un reparo óseo ubicado en el cóndilo lateral de la tibia, corresponde a un referente anatómico y clínico importante para inserción de músculos, ligamentos y procedimientos medicoquirúrgicos de la rodilla. A pesar de esta amplia denominación, y en comparación con otros epónimos, la TAI no la incluye y no relaciona algún término oficial con esta estructura anatómica. El objetivo del trabajo fue revisar libros usados en la enseñanza de la anatomía y artículos científicos actualizados para ver la presencia y descripción de esta estructura a fin de proponer un término que se ajuste a los principios básicos de la Terminología Anatómica Internacional en concordancia con la tarea del Programa Federativo Internacional de Terminología Anatómica (FIPAT), organismo de la Federación Internacional de Asociaciones de Anatomistas (IFAA). El TG se describe como una estructura ubicada entre la tuberosidad de la tibia y la cabeza de la fíbula, refiriéndose a él con sinónimos como tubérculo del músculo tibial anterior, tubérculo del músculo tensor de la fascia lata, tubérculo del tracto iliotibial y tubérculo anterolateral de la tibia. En revistas morfológicas aparece en artículos actuales relacionados al ligamento anterolateral. Según la descripción de la literatura proponemos como término anatómico para esta estructura "Tuberculum anterolateralis tibiae", cuya traducción es usada como sinónimo por otros autores, ajustándose así a los principios básicos de la TAI. Pretendemos que estos antecedentes sean discutidos por los expertos que conforman el FIPAT.


In teaching anatomy, the use of eponyms is increasingly scarce. Nonetheless, eponyms remain evident in updated literature, in this case the use of the eponym is accompanied by the correct term according to the International Anatomical terminology (TAI) Gerdy´s tubercle (GT) is an eponym widely used in the literature and scientific community to name a lateral tubercle of the tibia. It is an insertion site of muscles and ligaments and an important anatomical reference in knee surgical procedures. Despite its importance, it is not included in the International Anatomical Terminology (IAT) and an official name for this structure is lacking. The aim of this work was to review classic books used in the anatomy teaching and recent scientific papers, and further, to propose an anatomical term for the Gerdy tubercle that fit IAT basic principles, in agreement with the International Federal Program of Anatomical Terminology (IFPAT), and organism that is part of the International Federation of Anatomist Associations (IFAA). The TG is described as a structure located between the tuberosity of the tibia and the head of the fibula, referring to it with synonyms such as tubercle of the anterior tibia, tubercle of the tensor fascia lata, tubercle of iliotibial tract and anterolateral tibial tubercle. In morphological journals it appears in current articles related to the anterolateral ligament. We propose as an anatomical term for the Gerdy´s tubercle the name of "Tuberculum anterolteralis tibiae" its translation is used as a synonym by other authors and fits the basic principles of TAI. We hope that this information be considered by the experts that make up the FIPAT.


Humans , Tibia/anatomy & histology , Eponyms , Terminology as Topic
5.
Int. j. morphol ; 37(3): 953-958, Sept. 2019. tab, graf
Article Es | LILACS | ID: biblio-1012380

La correcta utilización de los términos morfológicos está estandarizada por las terminologías, una de ellas es la Terminologia Histologica (TH). Éstas sugieren la exclusión de los epónimos. Pese a esto, existen estructuras que continúan en esta condición. Específicamente, "Poros de Kohn, Canales de Martin y Canales de Lambert" son términos que componen la ventilación colateral (VC) y son ejemplo de esta situación. Así, el objetivo del presente estudio fue identificar en TH los términos asociados a la VC a fin de proponer denominaciones siguiendo las recomendaciones de la Federación Internacional de Programas de Terminologías Anatómicas (FIPAT). Se buscaron los términos relacionados a la VC en TH, posteriormente, se efectuó el mismo ejercicio en textos de histología, además de esto, en base de datos MedLine a través de su buscador PudMed con el siguiente algoritmo: (lung) AND (alveoli pulmonary) AND (airway) AND (collateral) AND (ventilation). En TH se encontró el término Porus septalis (H3. 05.02.0.00036) para referirse al término Poros de Kohn, en seis textos de histología se menciona el término Poros de Kohn, en 21 artículos revisados se menciona la VC, de estos, en diez se utiliza el epónimo Poro de Kohn, para referirse a los poros septales, el epónimo Canales de Lambert fue utilizado en seis artículos y el epónimo Canales de Martin, apareció en cinco artículos. A partir de la información encontrada, su desarrollo histórico, sumado a los lineamientos de la FIPAT, proponemos complementar e incluir en TH los términos Porus septalis alveolaris para los poros de Kohn, Ductus bronchiolaris alveolaris para los Canales de Lambert y Ductus interbronquiolaris para los canales de Martin, respectivamente.


The correct use of morphological terms is standardized by the Terminologies, one of them is the Histological Terminology (HT) For these Terminologies, the exclusion of eponyms is recommended. Despite this, there are structures that remain as eponyms. Three in particular: Pores of Kohn, Martin Channels and Lambert Channels are terms that make up collateral ventilation (CV) and are an example of this. Thus, the objective of the present study was to identify in the HT the terms associated with the CV in order to propose denominations following the recommendations of the Federative International Programme on Anatomical Terminologies (FIPAT). The terms related to CV in the TH were researched, and subsequently, the same exercise was carried out in histology texts. The MedLine database was also used through its PudMed search engine with the following algorithm: (lung) AND (alveoli pulmonary) AND (airway) AND (collateral) AND (ventilation). In HT the term Porus Septalis" (H3.05.0.0.036) was found to refer to the term "Pores of Kohn, in six histology texts the term Pores of Kohn is mentioned, in 21 reviewed articles the CV is mentioned, of these, in ten the eponymous Pores of Kohn is used, to refer to the Septal Pores, the eponymous Lambert Channels was used in six articles and the eponymous Martin Channels appeared in five articles. From the information found, its historical development, added to the guidelines of the FIPAT, we propose complementing and including in the HT the terms "Porus septalis alveolaris" for pores of Kohn, "Ductus bronchiolaris alveolaris" for the Lambert Channels and "Ductus interbronquiolaris" for the Martin Channels, respectively.


Humans , Pulmonary Alveoli/anatomy & histology , Bronchi/anatomy & histology , Terminology as Topic , Pulmonary Ventilation , Eponyms
6.
Environ Monit Assess ; 190(4): 254, 2018 Mar 28.
Article En | MEDLINE | ID: mdl-29594627

Streams of the Pampasic plain in Southeastern South America are ecosystems affected by both water pollution and habitat alteration mainly due to agricultural activity. Water quality is influenced by the quality of habitats and both depend on land use and watershed morphology. The objective of this study was to determine the relationship between the variables of four factors: (1) the morphology of the watershed, (2) land use in the watershed, (3) river habitat, and (4) water quality of wadeable streams in Uruguay, as well as to determine the most representative variables to quantify such factors. We studied 28 watersheds grouped into three ecoregions and four principal activities, which generated seven zones with three to five streams each. Correlations between the variables of each factor allowed reducing the total number of variables from 57 to 32 to perform principal component analyses (PCA) by factor, reducing the number of variables to 18 for a general PCA. The first component was associated with water quality and elevation. The second was associated with the stream and watershed size, the third with habitat quality, and the fourth to the use of neighboring soils and objects in the channel. Our results indicate that agricultural intensity and elevation are the main factors associated with the habitat and water quality of these lowland streams. These factors must be especially considered in the development of water quality monitoring programs.


Agriculture/statistics & numerical data , Ecosystem , Environmental Monitoring , Rivers/chemistry , Uruguay , Water Pollution/statistics & numerical data , Water Quality
7.
Int. j. morphol ; 28(2): 583-590, June 2010. ilus
Article Es | LILACS | ID: lil-577157

El conocimiento detallado de la inervación de las estructuras de la mano permite la restauración de sus funciones frente a lesiones a las que se encuentra frecuentemente sometida. El objetivo de esta investigación fue determinar la distribución del ramo profundo del nervio ulnar en los músculos intrínsecos del dedo mínimo, localizando el origen de cada ramo y su punto de ingreso en el vientre muscular en un grupo de individuos chilenos. Se disecaron 23 manos de cadáveres formolizados de individuos chilenos, adultos, pertenecientes a la Unidad de Anatomía de la Universidad de la Frontera, Chile, en las cuales se realizó disección de la región palmar, exponiendo los músculos hipotenares y el ramo profundo del nervio ulnar (RPNU) localizando a los ramos dirigidos a los músculos del dedo mínimo, determinando su origen, identificando ramos independientes o comunes y registrando el punto de ingreso en el músculo. La distribución del ramo profundo del nervio ulnar se clasificó en 4 tipos: en el tipo I hubo 1 ramo independiente para el músculo abductor del dedo mínimo (ADM) y un ramo común para los músculos flexor corto ( FCM) y oponente (ODM) del dedo mínimo en 43,4 por ciento; el tipo II, un ramo común para el ADM y FCDM y un ramo independiente para el ODM en 21,7 por ciento; el tipo III, 3 ramos independientes, uno para cada músculo propio del dedo mínimo en 30,4 por ciento y el tipo IV, 2 ramos independientes, uno para el ADM y el otro para ODM en 4,3 por ciento, destacando en este tipo la ausencia del FCDM. El conocimiento de los padrones y variaciones aquí descritas es un importante aporte para la anatomía quirúrgica de la mano.


Detailed knowledge of the innervation of the structures of the hand allows the restoration of normal function when dealing with injuries to which are frequently subject. The present study aims to observe the distribution of the deep branch of ulnar nerve in the intrinsic muscles of the digiti minimi, determining the origin of each branch and its point of entry into the muscle belly in a group of Chilean individuals. 23 formalized hands of Chilean individuals belonging to the unit of Anatomy at the Universidad de La Frontera, Chile, Were dissected. Dissection was performed in palmar regions, exposing the hypothenar muscles and the deep branch of ulnar nerve following muscular branches to determine the origin as independent or common trunk and recording the entry point into the muscle. According to the findings we classified the distribution of the deep branch of the ulnar nerve in 4 types: type I, we found 1 independent branch for abductor digiti minimi (ADM) and a common branch in flexor digiti minimi brevis (FDMB) and opponens digiti minimi (ODM) in 43.4 percent; in type II, a common branch for ADM and independent FDMB and an independent branch for the ODM in 21.7 percent; in type III, 3 independent branches, one for each muscle of the digiti minimi in 30.4 percent and a type IV, 2 independent branches, one for the ADM and the other for ODM, highlighting the absence of the FDMB. The knowledge of these patterns and variations is an important contribution for the surgical anatomy of the hand.


Humans , Hand/innervation , Muscle, Skeletal/innervation , Ulnar Nerve/anatomy & histology , Cadaver , Chile
8.
Rev. biol. trop ; 57(supl.1): 381-387, nov. 2009. tab
Article Es | LILACS, SaludCR | ID: lil-637951

Frecuency of the allele causing the axonal form of autosomal recessive Charcot-Marie-Tooth in Palmares, Costa Rica. The Charcot-Marie-Tooth disease constitutes is among the most frequent hereditary peripheral neuropathies world-wide. We identified a family from Palmares (Alajuela, Costa Rica) with 18 affected members. Their neuropathy is axonal, with an autosomal recessive pattern of inheritance; the responsible gene is at the 19q13.33 chromosomal region. Later the mutation was identified in gene MED25. We studied the frequency and geographic distribution of the mutant allele. In a random sample of 103 individuals, six were heterozygote and were widely distributed in Palmares. There was no person in homozigote state for the mutant allele. Clinical characteristics do not differ significantly between individuals that are homozygous for the wildtype allele and individuals hetero zygous for the mutation. A 5.83 % of the population is heterozygote and the frequency of the Ala335Val allele is 0.029, six times higher than in a sample of the Costa Rican population. Werecommend a molecular analysis of carriers to detect additional cases in the region. Rev. Biol. Trop. 57 (Suppl.1): 381-387. Epub 2009 November 30.


La enfermedad de Charcot-Marie-Tooth constituye elgrupo de neuropatías periféricas hereditarias más común a nivel mundial. Una familia con 18 afectados del cantón de Palmares (Alajuela, Costa Rica) con una neuropatía de tipo axonal y herencia autosómica recesiva, permitió localizar el gen responsable en la región 19q13.33. Posteriormente se identificó la mutación causante en el gen MED25. El presente estudio determinó la frecuencia del alelo mutante, así como la distribución geográfica de este alelo. En una muestra al azar de 103 individuos se encontraron seis individuos heteroigotas para la mutación, distribuidos por todo el cantón. No se encontró ninguna persona en estado homocigota para este alelo. No hallamos algunacaracterística clínica que difiera significativamente entre los individuos homocigotos silvestres y los heterocigotos para la mutación. El 5.83% de la población es heterocigota y la frecuencia del alelo Ala335Val es de 0.029, seis veces mayor que en una muestra de toda la población costarricense. Por esta razón se recomienda un análisis molecular de portadores con el fin de alertar sobre la posibilidad de aparición de más casos en el cantón.


Humans , Molecular Structure , Charcot-Marie-Tooth Disease/diagnosis , Gene Frequency , Costa Rica
9.
Rev. bras. ortop ; 28(8): 537-40, ago. 1993. ilus
Article Pt | LILACS | ID: lil-199626

Os autores descrevem uma modificaçäo de técnica na reconstruçäo do ligamento cruzado anterior do joelho (LCA) por via artroscópica, utilizando enxerto de tendäo patelar (osso-tendäo-osso) e parafusos de Kurosaka para fixaçäo no fêmur e na tíbia. Mencionam a importância da isometricidade e da escolha do tamanho ideal do enxerto, determinado após a tunelizaçäo simultânea na tíbia e no fêmur. No período compreendido entre março e setembro de 1992, 12 substituiçöes do LCA utilizando a técnica foram realizadas no Hospital de Tráumato-Ortopedia do Rio de Janeiro (HTO/RJ)


Humans , Male , Female , Adult , Middle Aged , Anterior Cruciate Ligament/surgery , Patellar Ligament/transplantation , Tendon Transfer/methods , Arthroscopy , Postoperative Period
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