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1.
Braz. j. biol ; 84: e253852, 2024. tab, graf
Article in English | LILACS, VETINDEX | ID: biblio-1355905

ABSTRACT

Abstract The aim objective of this study was to determine the trophic ecology of juvenile and adult Acestrorhynchus falcirostris during the rising and flood (high-water) period in six island lakes adjacent to the Solimões River. As such, we investigated: i) the trophic position, through the fractional trophic niche; ii) the niche breadth; iii) niche overlap and iv) the food strategy of the species. The specimens were collected during the years 2014 to 2017, using gillnets with mesh sizes ranging from 30 to 120mm between opposite knots. Through the analysis of stomach contents, the preference in the consumption of items of animal origin was observed. Juveniles consumed insects in greater proportions (IAi% = 50%), while adults consumed fish (IAi%=99,98%). Despite the large supply of food items available in the high-water period, juveniles were the only ones to consume items of allochthonous origin, such as insects. Juveniles presented a different dietary strategy and dietary composition to adults. Juveniles were omnivores with a generalist strategy, while adults were piscivores with a specialist strategy. Thus, the food composition, niche breadth, trophic position and feeding strategy of Acestrorhynchus falcirostris change due to the stage of development.


Resumo O objetivo deste estudo foi determinar a ecologia trófica de juvenis e adultos de Acestrorhynchus falcirostris durante o período de enchente e cheia em seis lagos de ilha adjacentes ao rio Solimões. Assim, investigamos: i) a posição trófica, através do nicho trófico fracional; ii) a largura de nicho; iii) sobreposição de nicho; iv) a estratégia alimentar. Os espécimes foram coletados durante os anos de 2014 a 2017, utilizando redes de emalhar com malha variando de 30 a 120mm entre nós opostos. Por meio da análise do conteúdo estomacal, observamos a preferência no consumo de itens de origem animal. Os juvenis consumiram insetos em maiores proporções (IAi% = 50%), enquanto os adultos consumiram preferencialmente peixes (IAi% = 99,98%). Apesar da grande oferta de alimentos disponíveis no período da cheia, os juvenis eram os únicos a consumir itens de origem alóctone, como por exemplo, os insetos. Os juvenis apresentaram uma estratégia alimentar e composição alimentar diferente para os adultos. Os juvenis foram considerados onívoros com uma estratégia generalista, enquanto os adultos foram considerados piscívoros com uma estratégia alimentar mais especialista. Assim, a composição alimentar, amplitude do nicho, posição trófica e a estratégia alimentar de Acestrorhynchus falcirostris muda em função do estágio de desenvolvimento.


Subject(s)
Animals , Rivers , Characiformes , Seasons , Lakes , Ecosystem , Food Chain , Fishes , Gastrointestinal Contents
2.
Braz. j. biol ; 842024.
Article in English | LILACS-Express | LILACS, VETINDEX | ID: biblio-1469327

ABSTRACT

Abstract The aim objective of this study was to determine the trophic ecology of juvenile and adult Acestrorhynchus falcirostris during the rising and flood (high-water) period in six island lakes adjacent to the Solimões River. As such, we investigated: i) the trophic position, through the fractional trophic niche; ii) the niche breadth; iii) niche overlap and iv) the food strategy of the species. The specimens were collected during the years 2014 to 2017, using gillnets with mesh sizes ranging from 30 to 120mm between opposite knots. Through the analysis of stomach contents, the preference in the consumption of items of animal origin was observed. Juveniles consumed insects in greater proportions (IAi% = 50%), while adults consumed fish (IAi%=99,98%). Despite the large supply of food items available in the high-water period, juveniles were the only ones to consume items of allochthonous origin, such as insects. Juveniles presented a different dietary strategy and dietary composition to adults. Juveniles were omnivores with a generalist strategy, while adults were piscivores with a specialist strategy. Thus, the food composition, niche breadth, trophic position and feeding strategy of Acestrorhynchus falcirostris change due to the stage of development.


Resumo O objetivo deste estudo foi determinar a ecologia trófica de juvenis e adultos de Acestrorhynchus falcirostris durante o período de enchente e cheia em seis lagos de ilha adjacentes ao rio Solimões. Assim, investigamos: i) a posição trófica, através do nicho trófico fracional; ii) a largura de nicho; iii) sobreposição de nicho; iv) a estratégia alimentar. Os espécimes foram coletados durante os anos de 2014 a 2017, utilizando redes de emalhar com malha variando de 30 a 120mm entre nós opostos. Por meio da análise do conteúdo estomacal, observamos a preferência no consumo de itens de origem animal. Os juvenis consumiram insetos em maiores proporções (IAi% = 50%), enquanto os adultos consumiram preferencialmente peixes (IAi% = 99,98%). Apesar da grande oferta de alimentos disponíveis no período da cheia, os juvenis eram os únicos a consumir itens de origem alóctone, como por exemplo, os insetos. Os juvenis apresentaram uma estratégia alimentar e composição alimentar diferente para os adultos. Os juvenis foram considerados onívoros com uma estratégia generalista, enquanto os adultos foram considerados piscívoros com uma estratégia alimentar mais especialista. Assim, a composição alimentar, amplitude do nicho, posição trófica e a estratégia alimentar de Acestrorhynchus falcirostris muda em função do estágio de desenvolvimento.

3.
Rev. biol. trop ; 71(1): e54636, dic. 2023. tab, graf
Article in Spanish | LILACS, SaludCR | ID: biblio-1550730

ABSTRACT

Resumen Introducción: La Rata de Magdalena, Xenomys nelsoni, es un roedor endémico de México, de distribución restringida a las selvas bajas caducifolias densas, en una pequeña región de la costa del Pacífico mexicano. Es una especie poco conocida, catalogada como "En Peligro" de acuerdo con la Unión Internacional para la Conservación de la Naturaleza (IUCN). Este desconocimiento unido a la alta tasa de deforestación de su hábitat hace que su conservación sea prioritaria. Objetivo: Realizar un recuento histórico de los registros depositados en las colecciones científicas, generar mapas de distribución potencial y analizar el estado de conservación de la especie. Método: Los datos de ocurrencia de las especies se obtuvieron de la literatura y bases de datos digitales y se analizaron por décadas. Se utilizaron los programas GARP y MaxEnt para generar los modelos de nicho ecológico. La importancia de las variables en el modelo se estimó mediante un análisis Jackknife. Resultados: A lo largo de 129 años 19 recolectores registraron 69 ejemplares, de los cuales 65 están depositados en siete colecciones internacionales y una nacional. Aunque la especie sólo se ha recolectado en Jalisco y Colima, la distribución potencial de X. nelsoni incluye también el estado de Michoacán. De esta área estimada, sólo el 1.5 % se encuentra dentro de un Área Natural Protegida. Conclusiones: Los resultados de la distribución potencial podrían ser utilizados para verificar la presencia de la especie en lugares donde no ha sido recolectada como el norte de la Reserva de la Biosfera Chamela-Cuixmala y en algunas zonas de la provincia fisiográfica Costas del Sur en el estado de Michoacán. Es necesario incrementar los muestreos en regiones poco estudiadas predichas por el modelo y aumentar el área de protección.


Abstract Introduction: The Magdalena Rat, Xenomys nelsoni, is a rodent endemic to Mexico, whose distribution is restricted to dense tropical dry forests in a small region on the Pacific coast of Mexico. It is a poorly known species categorized as "Endangered" by the International Union for Conservation of Nature (IUCN). This lack of knowledge and the high rates of deforestation of its habitat makes its conservation a priority. Objective: To summarize the historical records deposited in scientific collections, to create potential distribution maps, and to analyze the conservation status of the species. Methods: We obtained species occurrence data from literature and digital databases, analyzing them by the decade. We used GARP and MaxEnt software to generate the ecological niche models. The importance of the variables in the model was estimated using the Jackknife technique. Results: Over 129 years, 19 collectors registered 69 specimens, of which 65 are deposited in one national and seven international collections. Although the species has only been collected in Jalisco and Colima, the potential distribution for X. nelsoni also includes the state of Michoacán. Of this estimated area, only 1.5 % is in a Protected Natural Area. Conclusions: The results of the potential distribution could be used to verify the presence of the species in places where it has not been collected, such as the northern part of the Chamela-Cuixmala Biosphere Reserve and in some areas of the physiographic province Costas del Sur in the state of Michoacán. It is needed to increase samplings in the least studied regions predicted by the model and expand the area of protection.


Subject(s)
Animals , Rats , Rats/anatomy & histology , Ecosystem , Endangered Species , Mexico
4.
Rev. bras. ginecol. obstet ; 45(6): 333-336, June 2023. graf
Article in English | LILACS | ID: biblio-1449749

ABSTRACT

Abstract Isthmocele is a discontinuation of the myometrium at the uterine scar site in a patient with a previous cesarian section (CS). The cause of isthmocele appears to be multifactorial. Poor surgical technique, low incision location, uterine retroflection, obesity, smoking, inadequate healing of scars, and maternal age are possible related factors. Most patients with this condition are asymptomatic. However, women can present with postmenstrual bleeding, pelvic pain, subfertility, dysmenorrhea, infertility, and scar abscess. Brazil has one of the world s highest cesarean section rates. One of the consequences of the rising rate of CS is the isthmocele, an emerging female health problem. Here we report a case of mucinous cystadenoma arising in a uterine isthmocele, a complication, as far as we could investigate, not yet described in the literature.


Resumo Istmocele é a descontinuidade do miométrio no local da cicatriz uterina em paciente com cesariana anterior. A causa da istmocele parece ser multifatorial. Má técnica cirúrgica, baixa localização da incisão, retroflexão uterina, obesidade, tabagismo, cicatrização inadequada de cicatrizes e idade materna são possíveis fatores relacionados. A maioria dos pacientes com esta condição é assintomática. No entanto, as mulheres podem apresentar sangramento pós-menstrual, dor pélvica, subfertilidade, dismenorreia, infertilidade e abscesso cicatricial. O Brasil tem uma das maiores taxas de cesariana do mundo. Uma das consequências da taxa crescente de cesarianas é a istmocele, um problema emergente de saúde feminina. Aqui relatamos um caso de cistoadenoma mucinoso originado em uma istmocele uterina, uma complicação ainda não descrita, até onde pudemos investigar.


Subject(s)
Humans , Female , Middle Aged , Uterus/injuries , Cystadenoma, Mucinous
5.
Journal of Traditional Chinese Medicine ; (12): 2077-2081, 2023.
Article in Chinese | WPRIM | ID: wpr-997264

ABSTRACT

Based on the concept of “imbalance of qi movement with the latent cancer toxin”, it is believed that the development process of tumor pre-metastatic niche (PMN) could be summarized as tumor derived secretory factors, exosomes and other “cancer toxin”, which latent in the body, were diffusion-prone by means of meridians and membrane-sources. Besides, the latent toxin induced the imbalance of qi movement, especially the distant weakest qi, and the local sweat pore and collateral vessels were blocked, which resulted in phlegm and blood stasis, and the cross-aggregation of poison. We also proposed therapeutic principles of PMN as first regulating qi and then clearing and expelling toxin, and tried to discuss the theoretical model of traditional Chinese medicine for PMN based on the theory of qi regulation and detoxification, aimed at providing ideas for the future theory construction of traditional Chinese medicine prevention and treatment for malignant tumor metastasis.

6.
Tropical Biomedicine ; : 253-258, 2023.
Article in English | WPRIM | ID: wpr-1006801

ABSTRACT

@#Black soldier fly (Hermetia illucens (Linnaeus, 1758)) larvae inhibit oviposition of house fly (Musca domestica Linnaeus, 1758) by releasing a semiochemical, although in some situations, inhibition is only partial. We hypothesized that there is a certain period in the life cycle of black soldier fly when it can cause antibiosis of the house fly. Choice and non-choice tests were used to separately examine the effectiveness of each developmental stage of black soldier fly (egg, larval (phase I, II, and III), prepupal and pupal stages) and crude extract of larvae on house fly oviposition. Tests using each developmental stage were compared with controls lacking black soldier fly. The effects of black soldier fly on the number of newly hatched house fly larvae were evaluated and there was a significant difference between the test and control in the number of eggs laid by house fly for all phases of the black soldier fly larval stage. Strong inhibition was found in some black soldier fly larval phases. Significant differences in the numbers of house fly eggs oviposited in food containers treated with crude extract were found when compared with a control, confirming that chemicals from black soldier fly larvae resulted in inhibition of oviposition of house fly. The results from experiment also indicated that chemicals from black soldier larvae influenced the number of house fly larvae newly hatched from eggs.

7.
Chinese Pharmacological Bulletin ; (12): 1819-1823, 2023.
Article in Chinese | WPRIM | ID: wpr-1013688

ABSTRACT

Pericytes are essential components of vessel mural cells that function to regulate blood flow, clear or phagocytose debris, and are contractile cells enwrapping capillaries throughout the body. It controls vascular permeability and is involved in the development of blood vessels and is an important regulator and potential drug target of angiogenesis and vascular function. Pericytes are also thought to play a key role in the tumor microenvironment, especially during tumor growth and distal metastasis. Therefore,in this review we discuss the relationship between pericytes involved in tumor angiogenesis and tumor metastasis, as well as the use of targeted pericytes to treat tumors,with a view to providing a basis for subsequent studies.

8.
Rev. biol. trop ; 70(1)dic. 2022.
Article in English | LILACS, SaludCR | ID: biblio-1387708

ABSTRACT

Abstract Introduction: Neotropical seasonally dry forest (NSDF) climatic constraints increased endemism, and phylogenetic niche conservatism in species that are restricted to this biome. NSDF have a large number of endemic Capparaceae taxa, but it is unknown if phylogenetic niche conservatism has played a role in this pattern. Objective: We carried out an evolutionary analysis of the climatic niche of neotropical species of Capparaceae to identify whether the climatic constraints of NSDF have played a major role throughout the family's evolutionary history. Methods: Using three chloroplastic (ndhF, matK, rbcL) and one ribosomal (rsp3) DNA sequences, we proposed a date phylogeny to reconstruct the evolutionary climatic niche dynamics of 24 Neotropical species of Capparaceae. We tested the relationship between niche dissimilarity and phylogenetic distance between species using the Mantel test. Likewise, we used a set of phylogenetic comparative methods (PGLS) on the phylogeny of Capparaceae to reconstruct the main evolutionary historic events in their niche. Results: Capparaceae originated in humid regions and subsequently, convergent evolution occurred towards humid and dry forest during the aridification phases of the Middle Miocene (16-11 Mya). However, adaptation towards drought stress was reflected only during the precipitation of the coldest quarter, where we found phylogenetic signal (Pagel λ) for gradual evolution and, therefore, evidence of phylogenetic niche conservatism. We found convergent species-specific adaptations to both drought stress and rainfall during the Miocene, suggesting a non-phylogenetic structure in most climatic variables. Conclusions: Our study shows how the Miocene climate may have influenced the Capparaceae speciation toward driest environments. Further, highlights the complexity of climatic niche dynamics in this family, and therefore more detailed analyses are necessary in order to better understand the NSDF climatic constrictions affected the evolution of Capparaceae.


Resumen Introducción: Las limitaciones climáticas del bosque neotropical estacionalmente seco (NSDF) produjeron endemismo y conservadurismo filogenético del nicho en especies restringidas a este bosque. En las Caparáceas neotropicales se ha encontrado endemismo en los NSDF, pero se desconoce si el conservadurismo de nicho filogenético ha influido en su evolución. Objetivos: Se llevó a cabo un análisis evolutivo del nicho climático de las especies neotropicales de Capparaceae para evaluar si las limitaciones climáticas del bosque neotropical estacionalmente seco (NSDF) han jugado un papel importante a lo largo de la historia evolutiva de la familia. Métodos: Usando tres secuencias de ADN cloroplastico (ndhF, matK, rbcL) y una ribosomal (rsp3) se propuso una filogenia datada para reconstruir la dinámica evolutiva del nicho climático de 24 especies Neotropicales de Capparaceae. Utilizando la prueba de Mantel, se realizaron análisis para establecer si hay diferencia de nicho y la distancia filogenética entre especies. Asimismo, se emplearon un conjunto de métodos comparativos filogenéticos sobre la filogenia de la familia para reconstruir los principales eventos históricos evolutivos en su nicho. Resultados: Capparaceae se originó en regiones húmedas y posteriormente se dio una evolución convergente hacia bosque húmedo y seco durante las fases de aridificación del Mioceno Medio (16-11 Ma). Sin embargo, la adaptación al estrés por sequía se reflejó solo en la precipitación del cuarto más frío del año, donde se evidencio señal filogenética, evolución gradual y, por lo tanto, evidencia de conservadurismo de nicho filogenético. También se hallaron especies con adaptaciones convergentes específicas tanto al estrés por sequía como a las lluvias durante el Mioceno, sugiriendo la carencia de estructura filogenética en la mayoría de las variables climáticas. Conclusiones: Este estudio muestra cómo el clima del Mioceno pudo haber influenciado la especiación de Capparaceae hacia ambientes mas secos. Además, la compleja dinámica del nicho climático en esta familia y, por lo tanto, la necesidad de realizar análisis más detallados para comprender mejor como las constricciones climáticas del NSDF afectaron la evolución de Capparaceae.


Subject(s)
Climate Change , Forests , Capparaceae
9.
Femina ; 50(4): 240-245, 2022. ilus
Article in Portuguese | LILACS | ID: biblio-1380697

ABSTRACT

A istmocele (ou "defeito cicatricial de cesariana") é uma alteração anatômica na parede uterina responsável por formar um "nicho", que é visualizado como uma área hipoecoica por histerografia ou por outros métodos de imagem, devido a uma cicatrização inapropriada de uma cesárea anterior. Essa modificação leva a complicações ginecológicas e obstétricas. Este estudo pretendeu analisar, entre os fatores de risco, a relação da istmocele com a técnica de fechamento uterino, comparando a sutura em camada simples com a dupla. Foi realizada uma revisão de literatura por meio de pesquisa bibliográfica em diferentes bases de dados eletrônicos. Foram encontrados 31 artigos, todavia apenas 13 estudos foram incluídos no presente estudo após avaliação criteriosa. A técnica de fechamento uterino é um dos fatores de risco possível de prevenir, sendo que a sutura em camada simples é associada a maior chance de se desenvolver a istmocele. A sutura de camada simples (ancorada) incluindo o endométrio está relacionada a menor espessura miometrial residual, associada a probabilidade de ruptura uterina e a istmocele, que a camada dupla não ancorada com a exclusão do endométrio.(AU)


The isthmocele is an anatomical alteration in the uterine wall responsible for forming a "niche", which is visualized as a hypoechoic area by hysterography or other imaging methods, due to inappropriate healing of a previous cesarean section. This modification leads to gynecological and obstetric complications. This study aimed to analyze among the risk factors the relation of isthmocele and the uterine closure technique comparing the single- and double-layer suture. It was conducted an electronic based search in different electronic databases. The research led to the retrieval of 31 articles; however only 13 studies were included in the present research after careful reading. The uterine closure technique is one of the possible risk factors to be modified; the single-layer suture is associated with a greater chance of developing isthmocele. The locked single-layer suture including the decidua is related to the decreased residual myometrial thickness, associated with the likelihood of uterine rupture and the isthmocele, than the double-layer unlocked excluding the decidua.(AU)


Subject(s)
Humans , Female , Pregnancy , Cesarean Section/adverse effects , Cesarean Section/methods , Abdominal Wound Closure Techniques/adverse effects , Uterine Rupture , Risk Factors , Databases, Bibliographic
10.
Neotrop. ichthyol ; 20(1): e210103, 2022. tab, graf
Article in English | LILACS, VETINDEX | ID: biblio-1365205

ABSTRACT

We assessed the flood pulse effect on the diet composition, trophic niche breadth, and the amount of food intake of two Amazonian auchenipterids with different feeding strategies. Sampling was carried out quarterly (from April/2012 to January/2014) on the middle Xingu River, using gillnets. We measured specimens for standard length and total weight. The specimens' stomachs were removed, weighed, and had their contents identified. We analyzed 360 stomachs of Auchenipterus nuchalis and 584 of Tocantinsia piresi. The diet of A. nuchalis was mainly composed of aquatic insects and crustaceans, while T. piresi fed on fruits and seeds. The diet composition of both species varied seasonally, but only T. piresi changed its trophic niche breadth in response to hydrological changes, becoming more specialist during the higher water periods (filling and flood). Both species also showed differences in their amount of food intake between hydrological periods, with A. nuchalis feeding more intensely in lower water periods (ebb and dry), while T. piresi in the higher water periods. We evidenced different responses to the hydrological periods for the related species. We emphasize that studies considering the relationship between flood pulse and feeding ecology of the organisms are essential to understanding river floodplain systems' dynamics.(AU)


Avaliamos o efeito do pulso de inundação na composição da dieta, amplitude de nicho trófico e quantidade de alimento ingerido de dois auchenipterídeos amazônicos com diferentes estratégias alimentares. Os espécimes foram amostrados trimestralmente entre abril/2012 e janeiro/2014 no médio rio Xingu, utilizando malhadeiras. Estes foram mensurados quanto ao comprimento padrão e peso total. Os estômagos dos espécimes foram removidos, pesados e seu conteúdo identificado. Analisamos 360 estômagos de Auchenipterus nuchalis e 584 de Tocantinsia piresi. A dieta de A. nuchalis foi predominantemente composta por insetos aquáticos e crustáceos, enquanto para T. piresi frutos e sementes predominaram. A composição da dieta de ambas as espécies variou sazonalmente, mas apenas para T. piresi a amplitude de nicho trófico variou entre períodos hidrológicos, sendo mais especialista nos períodos de águas altas (enchente e cheia). Ambas as espécies diferiram na quantidade de alimento ingerido entre os períodos hidrológicos, sendo maior para A. nuchalis nos períodos de águas baixas (vazante e seca) e para T. piresi nos períodos de águas altas. Evidenciamos diferentes respostas à variação hidrológica pelas espécies. Enfatizamos que estudos considerando a relação entre a dinâmica do pulso de inundação e a ecologia alimentar dos organismos é fundamental para um melhor entendimento da dinâmica das planícies de inundação.(AU)


Subject(s)
Animals , Catfishes , Crustacea , Eating , Trophic Levels/analysis , Seeds
11.
Acta Pharmaceutica Sinica B ; (6): 364-377, 2022.
Article in English | WPRIM | ID: wpr-929300

ABSTRACT

Up to 70% of patients with late-stage breast cancer have bone metastasis. Current treatment regimens for breast cancer bone metastasis are palliative with no therapeutic cure. Disseminated tumor cells (DTCs) colonize inside the osteogenic niches in the early stage of bone metastasis. Drug delivery into osteogenic niches to inhibit DTC colonization can prevent bone metastasis from entering its late stage and therefore cure bone metastasis. Here, we constructed a 50% DSS6 peptide conjugated nanoparticle to target the osteogenic niche. The osteogenic niche was always located at the endosteum with immature hydroxyapatite. Arsenic-manganese nanocrystals (around 14 nm) were loaded in osteogenic niche-targeted PEG-PLGA nanoparticles with an acidic environment-triggered arsenic release. Arsenic formulations greatly reduced 4T1 cell adhesion to mesenchymal stem cells (MSCs)/preosteoblasts (pre-OBs) and osteogenic differentiation of osteoblastic cells. Arsenic formulations also prevented tumor cell colonization and dormancy via altering the direct interaction between 4T1 cells and MSCs/pre-OBs. The chemotactic migration of 4T1 cells toward osteogenic cells was blocked by arsenic in mimic 3D osteogenic niche. Systemic administration of osteogenic niche-targeted arsenic nanoparticles significantly extended the survival of mice with 4T1 syngeneic bone metastasis. Our findings provide an effective approach for osteogenic niche-specific drug delivery and suggest that bone metastasis can be effectively inhibited by blockage of tumor cell colonization in the bone microenvironment.

12.
Acta Pharmaceutica Sinica ; (12): 2601-2611, 2022.
Article in Chinese | WPRIM | ID: wpr-941493

ABSTRACT

The bone marrow microenvironment, also known as the bone marrow niche, plays a critical role in maintaining the functions of hematopoietic stem cells. Under physiological conditions, various bone marrow cells regulate each other to sustain hematopoietic homeostasis. However, bone marrow cells gain abnormal function under pathological conditions to cause and promote the occurrence of leukemia and induce drug resistance. Recent findings indicate that abnormal proliferation and differentiation are not the sole reason to cause leukemia. Different types of bone marrow cells also induce intercellular adhesion, abnormally secrete cytokines and chemokines, accelerating leukemia's progress. This article reviews the multiple signaling pathways that regulate the formation and progress of leukemia bone marrow niche, such as C-X-C motif chemokine ligand 12/C-X-C motif chemokine receptor 4 signaling pathway, et al. It emphasizes that targeting leukemia bone marrow niche is a vital strategy for improving the leukemia treatment.

13.
Chinese Pharmacological Bulletin ; (12): 975-979, 2022.
Article in Chinese | WPRIM | ID: wpr-1014049

ABSTRACT

Breast cancer is currently one of the caneers with the highest incidence.Clinically, most breast eaneer patients often die due to distant metastasis.In the complex easeade of metasta¬sis, the formation of the pre-metastasis niche ( PMN) has been considered to he cnrcial in the process of distant metastasis of tumors in recent years.Tumors at the primary site secrete tumor- derived secretory factors (TDSF) , extracellular vesicles ( EV) and so on to metastasize target organs.thereby changing the mi- croenvironment of the target organs to adapt to the subsequent distant metastasis of the tumor.Breast cancer is a kind of cancer number of studies have revealed the mechanism of the breast cancer pre-metastatic niche, showing that inhibiting the PMN can reduce breast cancer metastasis.The multi-target and multi- component features of traditional Chinese medicine have been re¬ported to effectively interfere with the formation of PMN.This review summarizes the breast cancer's mechanism of lung pre- metastatic niche formation and traditional Chinese medicine in¬tervention.

14.
Chinese Pharmacological Bulletin ; (12): 1681-1687, 2022.
Article in Chinese | WPRIM | ID: wpr-1013990

ABSTRACT

Aim To investigate the injury of 5-fluorouracil(5-FU)to perivascular hematopoietic niche via isolating mouse bone marrow perivascular mesenchymal progenitor cells in vitro and its related mechanism. Methods The perivascular mesenchymal progenitor cells were isolated from femurs and tibias of C57BL/6J mice with type Ⅱ collagenase and cultured in vitro. Agarose gel electrophoresis was used to detect specific niche genes expression. The viable cells were counted by Trypan blue; the cellular proliferation was detected by CCK-8; the apoptosis was detected by Annexin V/PI double staining, and the cell senescence was detected by β-galactosidase staining. The levels of malondialdehyde(MDA)and superoxide dismutase(SOD)were detected by enzymatic assay. Osteogenic and adipogenic differentiation potential of cells were detected by osteogenic and adipogenic differentiation experiment and osteogenic related genes qRT-PCR assay. The mRNA expression of hematopoietic growth factors was detected by qRT-PCR. Hematopoietic cells were co-cultured with perivascular mesenchymal progenitor cells, and the adhesion molecules and signal molecules between stromal cells and hematopoietic cells were detected, also hematopoietic cell activity, redox indicators and β-galactosidase specific cell senescence were detected. Results 5-FU caused simultaneous apoptosis and senescence of perivascular mesenchymal progenitor cells, inhibited cell proliferation, induced oxidative stress, led to osteogenic/adipogenic differentiation imbalance, and down-regulated the transcription of hematopoietic factors SCF, CXCL12, and G-CSF. For the interaction between stromal cells and hematopoietic cells, the binding effects of VLA-4/VCAM-1, ICAM-1/LFA1 were weakened and TPO/MPL and ANG-1/Tie-2 signals were impaired, leading to oxidative stress of hematopoietic cells and cell senescence. Conclusions 5-FU induces oxidative damage of perivascular mesenchymal progenitor cells and indirectly induces premature senescence of hematopoietic cells.

15.
Acta biol. colomb ; 26(3): 352-364, sep.-dic. 2021. tab, graf
Article in Spanish | LILACS-Express | LILACS | ID: biblio-1360030

ABSTRACT

RESUMEN En Ecuador las especies exóticas invasoras (EEI) provocan consecuencias negativas en los aspectos ecológicos, económicos y de seguridad alimentaria. Los agroecosistemas hacen parte de los sectores productivos a nivel mundial, pero son vulnerables a sufrir invasiones biológicas por la constante actividad humana y por el traslado de vegetación, tierra y semillas, por lo que deben ser constantemente monitoreados, pues desempeñan un papel importante en la economía al ser fuente de empleo. El objetivo de esta investigación fue evaluar la influencia potencial de las EEI sobre los agroecosistemas de Ecuador continental a través del modelado del nicho ecológico. Se usó como método de modelación el algoritmo de máxima entropía y se emplearon los registros de presencia de seis especies de plantas, tres insectos y un molusco en sus regiones nativas y en zonas invadidas a nivel mundial. Los registros provienen de Global Biodiversity Information Facility y de Tropicos. Como variables explicativas se emplearon 19 variables bioclimáticas y seis variables de vegetación. Se obtuvieron los mapas de distribución geográfica potencial, las áreas de superposición de la distribución de las especies y la delimitación de las zonas de mayor riesgo. Se determinó que las condiciones ambientales de las regiones Sierra y Amazónica son idóneas para una posible invasión de seis y siete especies. Además, más del 50 % de la cobertura agropecuaria del país podría ser afectada por las especies Wasmannia rochai, Spondias purpurea L., Lissachatina fúlica y Conium maculatum L., siendo los cultivos de ciclo corto los más vulnerables a la invasión por estas especies.


ABSTRACT In Ecuador, invasive alien species (IAS) cause negative consequences in ecology, economy, and food security. Agroecosystems belong to one of the productive sectors worldwide but are vulnerable to biological invasions by constant human activity and the transfer of vegetation, soil, and seeds, so they must be constantly monitored because of their important role in the economy to be a source of employment. The objective of this research was to evaluate the potential influence of IAS on the agroecosystems of continental Ecuador through the modeling of the ecological niche. The maximum entropy algorithm was used as a modeling method, and the presence register in the native region and invaded areas at a global level of six plant species, three insect species and one mollusc species were used. Data were obtained from the Global Biodiversity Information Facility and Tropicos. As explanatory variables, 19 bioclimatic variables, and six vegetation variables were used. Maps of potential geographical distribution, the overlap areas of the distribution of the species, and the delimitation of the zones of greater risk were obtained. It was determined that the environmental conditions of the Sierra and the Amazonian regions are ideal for a possible invasion of most species. Moreover, more than 50 % of the agricultural coverage of the country could be affected by Wasmannia rochai, Spondias purpurea L., Lissachatina fulica, and Conium maculatum L., with short cycle crops being the most vulnerable to invasion.

16.
Rev. biol. trop ; 69(4)dic. 2021.
Article in English | LILACS, SaludCR | ID: biblio-1387691

ABSTRACT

Abstract Introduction: Resource partitioning by promoting coexistence is essential to determine species richness and composition in natural communities. However, the partitioning of time has been questioned as a mechanism that promotes the coexistence of ecologically similar species. Objective: To determine the importance of the partitioning of time as a mechanism that promotes coexistence, we compared the activity patterns of tropical frugivorous bats. Methods: We captured bats with mist nets from sunset to sunrise in three study sites (tropical dry forest, wet forest, and rainforest) to calculate activity patterns of the species using Kernel density estimation. We used the superposition coefficient (Δ1) to compare activity patterns between (1) bat assemblages of study sites, (2) frugivorous species in the same site, and (3) populations of the same species among different sites. To determine whether the overlap in the activity patterns was related to the ecological similarity of species, we evaluated the association between Δ1 and similarity in abundances and body mass and phylogenetic closeness. Results: We found geographical variations in the overall activity patterns of the assemblages of the three localities. Likewise, we found variations in activity patterns between species at each study site and between populations in different study sites. Overlap in activity patterns tended to decrease as species were phylogenetically more closely related and similar in abundance and body size. Conclusions: Our results provide empirical support for the role of temporal segregation in activity patterns as a mechanism that promotes the coexistence of ecologically similar species in nature.


Resumen Introducción: La partición de recursos es esencial para determinar la riqueza y composición de especies en las comunidades naturales. Sin embargo, la segregacion temporal ha sido cuestionada como un mecanismo que promueve la coexistencia de especies ecológicamente similares. Objetivo: Con el fin de determinar la importancia de la segregación en los patrones de actividad, como mecanismo que promueve la coexistencia; se compararon los patrones de actividad de murciélagos frugívoros neotropicales. Métodos: Se capturaron murciélagos con redes de niebla desde el atardecer hasta el amanecer en tres localidades (bosque seco tropical, bosque muy húmedo y bosque lluvioso submontano) con el fin de calcular los patrones de actividad de las especies empleando la estimación de densidad Kernel. Se utilizó el coeficiente de superposición (Δ) para comparar patrones de actividad entre: (1) ensamblajes de murciélagos de los sitios de estudio, (2) especies frugívoras en el mismo sitio, y (3) poblaciones de la misma especie en diferentes sitios. Resultados: Se encontraron variaciones geográficas en los patrones de actividad de los ensamblajes en las tres localidades. Asimismo, se encontraron variaciones en los patrones de actividad entre especies en cada sitio y entre poblaciones en diferentes sitios. Determinamos que la superposición en los patrones de actividad disminuyó a medida que las especies estaban más relacionadas filogenéticamente, similares en abundancia y tamaño corporal; lo que sugiere una tendencia hacia la segregación temporal de especies ecológicamente similares. Conclusión: Estos resultados proveen apoyo empírico del papel de la segregación temporal en los patrones de actividad como un mecanismo que promueve la coexistencia de especies ecológicamente similares en la naturaleza.


Subject(s)
Animals , Chiroptera/classification , Biota
17.
Rev. peru. biol. (Impr.) ; 28(3)jul. 2021.
Article in English | LILACS-Express | LILACS | ID: biblio-1508861

ABSTRACT

Activity, microhabitat use, and diet are patterns commonly used to define the saurian community structure, because of differential exploitation allowing coexistence at the same time and place. We analyze resource partitioning between two sympatric saurian species, Stenocercus puyango and Microlophus occipitalis, in the transitional area of the Pacific Tropical Forest and the Dry Forest inside Cerros de Amotape National Park (PNCA) in Tumbes, northwestern of Peru. Microlophus occipitalis and S. puyango both showed a unimodal activity pattern with higher activity around 13:00 h, with a mean body temperature of 34.83 °C and 32.17 °C respectively, observing a significant relationship between body and environmental (air and substrate) temperatures. Rocks and tree trunks were the most frequent microhabitats used by M. occipitalis while S. puyango were registered more frequently over leaf litter. The diets of both tropidurids were composed by arthropods, ants, and insect larvae mainly. Similarities in activity times (temporal niche) and diet (trophic niche) should be related to phylogenetic relationship and environmental characteristics of PNCA (seasonality, vegetal composition) meanwhile differences in space use and microhabitat thermal quality will be related to thermal quality in the area.


Los horarios de actividad, el uso de microhábitat y dieta, son patrones comúnmente utilizados para dilucidar la estructura de una comunidad de saurios, ya que estos hacen un uso diferenciado de los recursos que explotan, lo que les permite coexistir de forma adecuada en el mismo tiempo y lugar. Analizamos la repartición de recursos entre dos especies simpátridas de saurios, Stenocercus puyango y Microlophus occipitalis, en la zona transicional entre el Bosque Tropical del Pacifico y el Bosque Seco en el Parque Nacional Cerros de Amotape (PNCA), departamento de Tumbes, analizando el solapamiento del nicho espacial, temporal y trófico entre ambas especies, incluyendo algunos aspectos de sus ecologías termales. Microlophus occipitalis y S. puyango presentaron un patrón de actividad unimodal con un pico de actividad hacia las 13:00 horas y una temperatura corporal promedio de 34.83 °C y 32.17 °C, respectivamente, registrándose una relación significativa entre la temperatura corporal y las temperaturas ambientales (aire y suelo). Los microhábitats más utilizados por M. occipitalis fueron los troncos caídos y rocas, mientras que S. puyango fue registrado principalmente sobre hojarasca. La dieta de ambos tropidúridos estuvo compuesta por artrópodos, principalmente hormigas y larvas de insectos. Las similitudes encontradas tanto en los horarios de actividad (nicho temporal) como en la dieta (nicho trófico), estarían asociadas a su parentesco filogenético y a características ambientales propias dentro del PNCA (estacionalidad, composición vegetal), mientras que las diferencias en el uso del espacio y temperaturas corporales entre ambas especies estarían relacionada a la calidad térmica de los microhábitats presentes en el área.

18.
Rev. biol. trop ; 69(2)jun. 2021.
Article in English | LILACS, SaludCR | ID: biblio-1387655

ABSTRACT

Abstract Introduction: One of the significant threats to aquatic ecosystems is introducing non-native species in natural environments. This represents one of the principal causes of biodiversity loss in the world. Pangasianodon hypophthalmus is an introduced species in Colombia that shares life characteristics and habitat with endangered native species, such as Ageneiosus pardalis, Sorubim cuspicaudus, and Pseudoplatystoma magdaleniatum. However, its distribution is little-known, and scientists have barely explored the effects on the native fauna. Objectives: To evaluate the P. hypophthalmus invasive potential in some of the Colombian basins, which drain into the Caribbean Sea. Methods: Using records available in various databases, we performed a niche conservatism analysis between the native and introduced records of P. hypophthalmus using the R package Ecospat. Subsequently, we modeled the potential invasion area of P. hypophthalmus and the distribution areas of three native species, performing ecological niche modeling (ENM) using the Maxent algorithm. Finally, we calculated a geographic niche overlap between the non-native and native species. Results: The Ecospat spatial analysis indicated that P. hypophthalmus retains some environmental niche attributes through space. For this reason, we can use ENM as an approximation to its range of distribution in the invaded area. Our results using ENM demonstrated that the four species analyzed prefer low and slightly rocky regions; therefore, the geographical overlap of the three native species' ecological niches and the introduced species exceed 80 %. Conclusions: There are adequate conditions in the study basins to fully establish the species P. hypophthalmus, representing a high risk for aquatic ecosystems and native ichthyofauna. Knowledge of the potential distribution areas is essential to implement control of the species.


Resumen Introducción: Una de las amenazas importantes para los ecosistemas acuáticos es la introducción de las especies no nativas en ambientes naturales. Esto representa una de las principales causas de pérdida de biodiversidad en el mundo. Pangasianodon hypophthalmus es una especie introducida en Colombia que comparte características de vida y hábitat con especies nativas en peligro de extinción como: Ageneiosus pardalis, Sorubim cuspicaudus y Pseudoplatystoma magdaleniatum. Sin embargo, poco se conoce de su distribución y los efectos en la fauna nativa han sido poco explorados. Objetivo: Evaluar el potencial invasivo de P. hypophthalmus en algunas de las cuencas colombianas que desembocan en el Mar Caribe. Métodos: Utilizando registros disponibles en varias bases de datos, realizamos un análisis de conservadurismo de nicho entre los registros nativos e introducidos de P. hypophthalmus usando el paquete de R Ecospat. Posteriormente, modelamos el área potencial de invasión de P. hypophthalmus y las áreas de distribución de tres especies nativas realizando modelos de nicho ecológico (MNE) utilizando el algoritmo de Maxent. Finalmente, calculamos una superposición de nicho geográfico entre las especies nativas y no nativas. Resultados: El análisis espacial de Ecospat indica que P. hypophthalmus conserva algunos atributos del nicho ambiental a través del espacio. Por esta razón, podemos usar los MNE como una aproximación a su rango de distribución en el área invadida. Nuestros resultados usando MNE demostraron que las cuatro especies analizadas prefieren regiones bajas y ligeramente rocosas; por ello, la superposición geográfica de los nichos ecológicos de las tres especies nativas y la especie introducidas superan el 80 %. Conclusiones: Existen condiciones adecuadas en las cuencas de estudio para el establecimiento completo de la especie P. hypophthalmus, lo que representa un alto riesgo para los ecosistemas acuáticos y la ictiofauna nativa. El conocimiento de las áreas de distribución potencial es fundamental para implementar controles sobre la especie.


Subject(s)
Animals , Catfishes , Introduced Species , Fishes , Colombia
19.
Rev. bras. entomol ; 65(1): e20200026, 2021. tab, graf
Article in English | LILACS-Express | LILACS | ID: biblio-1156004

ABSTRACT

Abstract A challenge for studies on the organization of ant assemblages in forest ecosystems is to disentangle the causal effects of species occurrences. The structural and functional attributes of trees can act as environmental filters for ground-dwelling ant species influencing resource availability and the microclimate. The biotic interactions, especially competition, can work together with plant characteristics influencing ant species occurrences. To test the importance of tree traits and species interactions on co-occurrence patterns of ants, we collected ground-dwelling ants, with pitfalls and litter sampling, beneath the canopies of four tree species during the rainy and dry seasons in a restored forest. We used five predictors (tree identity, crown size, trunk circumference, litter depth, and leaves density) to model the presence probabilities of ants . Hence, we applied habitat constrained null models in pairwise analyses to disentangle the causal effects of ants co-occurrences. The random pattern predominated in the assemblages, making up 96% of all possible species pairs combinations. Overall, 50% of the species pairs that showed nonrandomness in the ant occurrences were interpreted as resulting from environmental filters, 36% as negative associations and 14% as positive associations. Additionally, we found that the effects of season and the sampling technique on the ant assemblages were also important. We suggest that the ideas of the trees as templates and the paradigm of competition are both useful for understanding pairwise occurrence patterns in ant assemblages, and can be tested using tree traits as predictors in ant species distribution models for running constrained null models.

20.
Biota Neotrop. (Online, Ed. ingl.) ; 22(1): e20201145, 2021. tab, graf
Article in English | LILACS-Express | LILACS | ID: biblio-1355775

ABSTRACT

Abstract: Information on distribution, number of populations, and biotic interactions are essential for assessing the threat status of species and to establish more effective conservation initiatives. Ecological niche modeling have been successfully applied to identify the potential distribution, even for rare species that have few recorded occurrence points. In this study, we evaluated the potential distribution and additionally generated the first data on the reproductive biology of Discocactus ferricola, due to its degree of threat and the absence of ecological data for that species. The potential distribution map highlighted areas with higher probability of occurrence of D. ferricola on the Residual Plateau of Maciço do Urucum located in Mato Grosso do Sul, Brazil. The occurrence of D. ferricola populations was limited to outcrops of flat ironstone (cangas) distributed in patches across the landscape, increasing the chances of serious threats, such as habitat loss due to mining and species extraction. We also found that D. ferricola is xenogamous. Therefore, in situ conservation actions must prioritize the maintenance of interactions with pollinators by preserving the flora and fauna of rocky outcrops and adjacent forests in areas of greater environmental suitability for D. ferricola. Our study highlights the use of ecological niche modeling and data on biotic interactions to evaluate species potential distribution, to guide new sampling efforts, and to assist conservation and management initiatives.


Resumo: Informações sobre distribuição, número de populações e interações bióticas são essenciais para avaliar o status de ameaça das espécies e estabelecer iniciativas de conservação mais eficazes. A modelagem de nicho ecológico tem sido aplicada com sucesso para identificar a distribuição potencial, mesmo para espécies raras que possuem poucos pontos de ocorrência registrados. Neste estudo, avaliamos a distribuição potencial e adicionalmente geramos os primeiros dados sobre a biologia reprodutiva de Discocactus ferricola, devido ao seu grau de ameaça e à ausência de dados ecológicos para essa espécie. O mapa de distribuição potencial destacou áreas com maior probabilidade de ocorrência de D. ferricola no Planalto Residual do Maciço do Urucum localizado em Mato Grosso do Sul, Brasil. A ocorrência de populações de D. ferricola foi limitada aos afloramentos ferruginosos planos (cangas) que são distribuídos em manchas pela paisagem, aumentando as chances de ameaças graves, como perda de habitat devido à mineração e extração da espécie. Também descobrimos que D. ferricola é xenogâmica. Portanto, ações de conservação in situ devem priorizar a manutenção das interações com os polinizadores através da preservação da flora e da fauna nos afloramentos rochosos e florestas adjacentes nas áreas de maior adequabilidade ambiental para D. ferricola. Nesse estudo, nós destacamos o uso da modelagem de nicho ecológico e de dados sobre interações bióticas para avaliar a distribuição potencial de espécies, orientar novos esforços de amostragem e auxiliar iniciativas de conservação e manejo.

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