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Background: Anthropogenic activities significantly impact natural ecosystems, leading to alterations in plant and pollinator diversity and abundance. These changes often result in shifts within interacting communities, potentially reshaping the structure of plant-pollinator interaction networks. Given the escalating human footprint on habitats, evaluating the response of these networks to anthropization is critical for devising effective conservation and management strategies. Methods: We conducted a comprehensive review of the plant-pollinator network literature to assess the impact of anthropization on network structure. We assessed network metrics such as nestedness measure based on overlap and decreasing fills (NODF), network specialization (H2'), connectance (C), and modularity (Q) to understand structural changes. Employing a meta-analytical approach, we examined how anthropization activities, such as deforestation, urbanization, habitat fragmentation, agriculture, intentional fires and livestock farming, affect both plant and pollinator richness. Results: We generated a dataset for various metrics of network structure and 36 effect sizes for the meta-analysis, from 38 articles published between 2010 and 2023. Studies assessing the impact of agriculture and fragmentation were well-represented, comprising 68.4% of all studies, with networks involving interacting insects being the most studied taxa. Agriculture and fragmentation reduce nestedness and increase specialization in plant-pollinator networks, while modularity and connectance are mostly not affected. Although our meta-analysis suggests that anthropization decreases richness for both plants and pollinators, there was substantial heterogeneity in this regard among the evaluated studies. The meta-regression analyses helped us determine that the habitat fragment size where the studies were conducted was the primary variable contributing to such heterogeneity. Conclusions: The analysis of human impacts on plant-pollinator networks showed varied effects worldwide. Responses differed among network metrics, signaling nuanced impacts on structure. Activities like agriculture and fragmentation significantly changed ecosystems, reducing species richness in both pollinators and plants, highlighting network vulnerability. Regional differences stressed the need for tailored conservation. Despite insights, more research is crucial for a complete understanding of these ecological relationships.
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Efeitos Antropogênicos , Ecossistema , Polinização , Animais , Agricultura , Biodiversidade , Conservação dos Recursos Naturais , Insetos/fisiologia , PlantasRESUMO
Abstract Introduction The suspension of clinical practices in the nursing profession during COVID-19 generated a decrease in the students՚ abilities and skills which made them vulnerable to more frequent to clinical practice stressors and levels of anxiety. Objective To determine the relation between clinical practice stressors and anxiety levels in nursing students during COVID-19. Method A descriptive correlational study with convenience sampling was carried out in 169 students enrolled from third to eight semesters in a public university in the city of Saltillo, Coahuila. For the measurement of variables a sociodemographic data card, the KEZKAK Questionnaire in its Spanish version to measure the clinical practice stressors and the Beck Anxiety Inventory were used. Data collection was through a digital link during August-December 2021. Descriptive and inferential statistics were sued through SPSS V.26. Results 57.4% reported a medium level of stress and 62.7% a low level of anxiety; however, there are stressors from clinical practice that lead to increased anxiety. A statistically significant positive correlation was found between the study variables (r = .411, p<.001). Discussion and conclusion The challenges in clinical practice experienced during COVID-19 highlight that generations of future nursing professionals face a scenario that is the product of a post-pandemic era, so it is necessary to strengthen their knowledge and confidence to motivate them to feel safe within the hospital context.
Resumen Introducción La suspensión en las prácticas clínicas en la profesión de enfermería durante la COVID-19, generó en los estudiantes disminución de sus habilidades y destrezas que los hizo vulnerables a presentar con mayor frecuencia estresores de la práctica clínica y niveles de ansiedad. Objetivo Determinar la relación entre los estresores de la práctica clínica y los niveles de ansiedad en estudiantes de enfermería durante la COVID-19. Método Se realizó un estudio de tipo descriptivo correlacional con muestreo por conveniencia en 169 estudiantes de tercero a octavo semestre matriculados en una universidad pública de la ciudad de Saltillo Coahuila. Para la medición de variables se utilizó la cédula de datos sociodemográficos, el Cuestionario KEZKAK para medir los estresores de la práctica clínica y el Inventario de Ansiedad de Beck. La colecta de datos fue a través de un enlace digital durante agosto-diciembre 2021. Se utilizó estadística descriptiva e inferencial a través del SPSS V.26. Resultados El 57.4% refiere un nivel medio de estrés y el 62.7% un bajo nivel de ansiedad; sin embargo, existen estresores provenientes de la práctica clínica que propician el aumento de ansiedad. Se encontró una correlación positiva estadísticamente significativa entre las variables de estudio (r = .411, p<.001). Discusión y conclusión Los retos en la práctica clínica experimentados durante la COVID-19, resaltan que las generaciones de futuros profesionistas en enfermería se enfrentan a un panorama producto de una época post-pandemia, por lo que es necesario afianzar sus conocimientos y su confianza para motivarlos a sentirse seguros dentro del contexto hospitalario.
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The coronavirus disease 2019 (COVID-19) has caused over six million deaths worldwide since its emergence in Wuhan China, factors associated with COVID-19 mortality, such as comorbidities, age, and observed symptomatology still remain a major subject of study. In the present work, a total of 16,345 SARS-CoV-2 positive cases from Durango Mexico diagnosed from May 2020 to December 2021 were analyzed to establish an association of COVID-19 mortality with clinical and demographic variables in a case-control study. Selected variables include patient age, smoking status, sex, presence of comorbidities such as hypertension, diabetes and obesity, as well as patient symptomatology such as fever, dyspnea, abdominal pain and diarrhea. Results indicate that among analyzed data, the median age was 43 years; 54% were female, with a mortality rate of 5.66%. Multivariate regression analysis indicated that the comorbidities associated with the highest risk factor were advanced age (>60) with an odds ratio of 4.127 (IC 95%, 3.37-5.05), hypertension with 1.961 (IC 95%, 1.57-2.45), diabetes with 1.753 (IC 95%, 1.39-2.20) and obesity with 1.413 (IC 95%, 1.11-1.78) respectively. On the other hand, the symptom associated with the highest risk factor was dyspnea with an odds ratio of 18.369 (IC 95%, 14.42-23.39). Our data suggests an association between hypertension and old age with COVID-19 mortality. Other findings include the prevalence of dyspnea, polypnea and cyanosis as a major predictor for COVID-19 mortality, as well as lower mortality risks among health workers.
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COVID-19 , Diabetes Mellitus , Hipertensão , Humanos , Feminino , Adulto , Masculino , COVID-19/epidemiologia , COVID-19/complicações , SARS-CoV-2 , Estudos de Casos e Controles , México/epidemiologia , Fatores de Risco , Comorbidade , Obesidade/epidemiologia , Obesidade/complicações , Diabetes Mellitus/epidemiologia , Hipertensão/epidemiologia , Hipertensão/complicações , Dispneia/epidemiologiaRESUMO
BACKGROUND: Ant-plant mutualistic networks tend to have a nested structure that contributes to their stability, but the ecological factors that give rise to this structure are not fully understood. Here, we evaluate whether ant abundance and dominance hierarchy determine the structure of the ant-plant networks in two types of vegetation: oak and grassland, in two temperate environments of Mexico: Flor del Bosque State Park (FBSP) and La Malinche National Park (MNP). We predicted that dominant and abundant ant species make up the core, and submissives, the periphery of the network. We also expected a higher specialization level in the ant trophic level than in plant trophic level due to competition among the ant species for the plant-derived resources. METHODS: The ant-plant interaction network was obtained from the frequency of ant-plant interactions. We calculated a dominance hierarchy index for the ants using sampling with baits and evaluated their abundance using pitfall traps. RESULTS: In MNP, the Formica spp. species complex formed the core of the network (in both the oak forest and the grassland), while in FBSP, the core species were Prenolepis imparis (oak forest) and Camponotus rubrithorax (grassland). Although these core species were dominant in their respective sites, they were not necessarily the most dominant ant species. Three of the four networks (oak forest and grassland in FBSP, and oak forest in MNP) were nested and had a higher number of plant species than ant species. Although greater specialization was observed in the ant trophic level in the two sites and vegetations, possibly due to competition with the more dominant ant species, this was not statistically significant. In three of these networks (grassland and oak forest of MNP and oak forest of FBSP), we found no correlation between the dominance hierarchy and abundance of the ant species and their position within the network. However, a positive correlation was found between the nestedness contribution value and ant dominance hierarchy in the grassland of the site FBSP, which could be due to the richer ant-plant network and higher dominance index of this community. CONCLUSIONS: Our evidence suggests that ant abundance and dominance hierarchy have little influence on network structure in temperate ecosystems, probably due to the species-poor ant-plant network and a dominance hierarchy formed only by the presence of dominant and submissive species with no intermediate dominant species between them (absence of gradient in hierarchy) in these ecosystems.
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The role of human papillomavirus (HPV) infection in penile carcinoma (PeC) is currently reported and about half of the PeC is associated with HPV16 and 18. We used a PCR-based strategy by using HPV general primers to analyze 86 penile carcinomas paraffin-embedded tissues. Some clinical data, the histological subtype, growth pattern, and differentiation degree were also collected. The amplified fragments were then sequenced to confirm the HPV type and for HPV16/18 variants. DNA samples were also subjected to relative real time PCR for hTERC gene copy number. Some clinical data were also collected. Global HPV frequency was 77.9%. Relative contributions was for HPV16 (85%), 31 (4.4%), 11 (4.4%), 58, 33, 18, and 59 (1.4% each one). Sequence analysis of HPV16 identified European variants and Asian-American (AAb-c) variants in 92% and in 8% of the samples, respectively. Furthermore hTERC gene amplification was observed in only 17% of the cases. Our results suggest that some members of HPV A9 group (represented by HPV16, 58, and 31) are the most frequent among PeC patients studied with an important contribution from HPV16 European variant. The hTERC gene amplification could be poorly related to penile epithelial tissue.
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Carcinoma/virologia , Papillomavirus Humano 16/isolamento & purificação , Infecções por Papillomavirus/virologia , Neoplasias Penianas/virologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/genética , Biópsia , Carcinoma/epidemiologia , Carcinoma/genética , Carcinoma/patologia , Distribuição de Qui-Quadrado , DNA Viral/isolamento & purificação , Amplificação de Genes , Genótipo , Testes de DNA para Papilomavírus Humano , Papillomavirus Humano 16/genética , Humanos , Masculino , México/epidemiologia , Pessoa de Meia-Idade , Infecções por Papillomavirus/epidemiologia , Inclusão em Parafina , Neoplasias Penianas/epidemiologia , Neoplasias Penianas/genética , Neoplasias Penianas/patologia , Fenótipo , Valor Preditivo dos Testes , RNA/genética , Reação em Cadeia da Polimerase em Tempo Real , Fatores de Risco , Telomerase/genética , Adulto JovemRESUMO
Miniaturization encourages the development of new manufacturing processes capable of fabricating features, like micro-channels, in order to use them for different applications, such as in fuel cells, heat exchangers, microfluidic devices and micro-electromechanical systems (MEMS). Many studies have been conducted on heat and fluid transfer in micro-channels, and they appeared significantly deviated from conventional theory, due to measurement errors and fabrication methods. The present research, in order to deal with this opportunity, is focused on a set of experiments in the micro-milling of channels made of aluminum, titanium alloys and stainless steel, varying parameters, such as spindle speed, depth of cut per pass (ap), channel depth (d), feed per tooth (fz) and coolant application. The experimental results were analyzed in terms of dimensional error, channel profile shape deviation from rectangular and surface quality (burr and roughness). The micro-milling process was capable of offering quality features required on the micro-channeled devices. Critical phenomena, like run-out, ploughing, minimum chip thickness and tool wear, were encountered as an explanation for the deviations in shape and for the surface quality of the micro-channels. The application of coolant and a low depth of cut per pass were significant to obtain better superficial quality features and a smaller dimensional error. In conclusion, the integration of superficial and geometrical features on the study of the quality of micro-channeled devices made of different metallic materials contributes to the understanding of the impact of calibrated cutting conditions in MEMS applications.
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BACKGROUND: One of the most frequent malignancies in women worldwide is carcinoma of the uterine cervix. High-risk human papillomavirus (HPV) infection is considered the most important etiological factor of uterine cervical cancer. Our aim was to identify novel cellular genes that could potentially act as predictive molecular markers for human cervical cancer by means of cDNA arrays. METHODS: We used cDNA arrays to examine the expression profiles of six cell lines derived from human cervical cancer, three HPV+ tumor samples and three normal (HPV-) epithelium tissues. Data normalization was performed and the top overexpressed genes were obtained. Hierarchical cluster was performed and, to validate some of the differentially expressed genes between normal and carcinogenic samples, semi-quantitative RT-PCR, in situ hybridization and immunohistochemistry were performed in tissue samples. RESULTS: Four genes were demonstrated to be consistently overexpressed in invasive cervical cancer biopsies; three novel genes not previously related to cervical cancer: MMP10, Lamc2 and Claudin 1. Moreover, overexpression of IL6 and VEGF was corroborated. CONCLUSIONS: The identification of characteristic molecular changes in cervical cells by carcinogenesis and HPV infection can lead to a better understanding of cervical cancer. cDNA arrays are beginning to provide new possible molecular markers for prognosis and diagnosis. This technology could eventually help to elucidate the biological differences of the particular mechanisms associated with each different HPV-type infection and those with a poor prognosis.
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Análise de Sequência com Séries de Oligonucleotídeos , Papillomaviridae/genética , Neoplasias do Colo do Útero/genética , Neoplasias do Colo do Útero/virologia , Linhagem Celular Tumoral , Feminino , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Imuno-Histoquímica , Hibridização In Situ , Infecções por Papillomavirus/complicações , Distribuição Aleatória , Neoplasias do Colo do Útero/etiologia , Neoplasias do Colo do Útero/patologiaRESUMO
BACKGROUND: Chromosomal Comparative Genomic Hybridization (CGH) has been applied to all stages of cervical carcinoma progression, defining a specific pattern of chromosomal imbalances in this tumor. However, given its limited spatial resolution, chromosomal CGH has offered only general information regarding the possible genetic targets of DNA copy number changes. METHODS: In order to further define specific DNA copy number changes in cervical cancer, we analyzed 20 cervical samples (3 pre-malignant lesions, 10 invasive tumors, and 7 cell lines), using the GenoSensor microarray CGH system to define particular genetic targets that suffer copy number changes. RESULTS: The most common DNA gains detected by array CGH in the invasive samples were located at the RBP1-RBP2 (3q21-q22) genes, the sub-telomeric clone C84C11/T3 (5ptel), D5S23 (5p15.2) and the DAB2 gene (5p13) in 58.8% of the samples. The most common losses were found at the FHIT gene (3p14.2) in 47% of the samples, followed by deletions at D8S504 (8p23.3), CTDP1-SHGC- 145820 (18qtel), KIT (4q11-q12), D1S427-FAF1 (1p32.3), D9S325 (9qtel), EIF4E (eukaryotic translation initiation factor 4E, 4q24), RB1 (13q14), and DXS7132 (Xq12) present in 5/17 (29.4%) of the samples. CONCLUSION: Our results confirm the presence of a specific pattern of chromosomal imbalances in cervical carcinoma and define specific targets that are suffering DNA copy number changes in this neoplasm.
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Aberrações Cromossômicas , Deleção Cromossômica , DNA de Neoplasias , Regulação Neoplásica da Expressão Gênica , Hibridização de Ácido Nucleico , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Neoplasias do Colo do Útero/genética , Linhagem Celular Tumoral , DNA/genética , Primers do DNA/química , Feminino , Células HeLa , Humanos , Processamento de Imagem Assistida por Computador , Perda de Heterozigosidade , Papillomaviridae/genética , Reação em Cadeia da Polimerase , Neoplasias do Colo do Útero/diagnóstico , Neoplasias do Colo do Útero/metabolismoRESUMO
BACKGROUND: Cervical carcinoma (CC) is one of the most common cancers among women worldwide and the first cause of death among the Mexican female population. CC progression shows a continuum of neoplastic transitions until invasion. Matrix metalloproteinases (MMPs) and cathepsins play a central role on the enhancement of tumor-induced angiogenesis, cell migration, proliferation, apoptosis and connective tissue degradation. MMPs -2 and -9 expression has been widely studied in cervical cancer. Nevertheless, no other metalloproteinases or cathepsins have been yet related with the progression and/or invasion of this type of cancer. METHODS: Three HPV18 CC cell lines, two HPV16 CC cell lines and three HPV16 tumor CC tissues were compared with three morphologically normal, HPV negative, cervical specimens by cDNA arrays. Overexpression of selected genes was confirmed by end point semiquantitative reverse transcription-PCR with densitometry. In situ hybridization and protein expression of selected genes was further studied by means of two tissue microarrays, one consisting of 10 HSIL and 15 CC and the other one of 15 normal cervical and 10 LSIL tissues. RESULTS: TIMP1, Integrins alpha 1 and 4, cadherin 2 and 11, Cathepsins F, B L2, MMP 9, 10 11 and 12 were upregulated and Cathepsin S, L, H and C, Cadherins 3 and 4, TIMP3, MMP 13, Elastase 2 and Integrin beta 8 were found to be downregulated by cDNA arrays. Endpoint RT-PCR with densitometry gave consistent results with the cDNA array findings for all three genes selected for study (CTSF, MMP11 and MMP12). In situ hybridization of all three genes confirmed overexpression in all the HSIL and CC. Two of the selected proteins were detected in LSIL, HSIL and CC by immunohistochemistry. CONCLUSION: Novel undetected CC promoting genes have been identified. Increased transcription of these genes may result in overexpression of proteins, such as CTSF, MMP11 and MMP12 which could contribute to the pathogenesis of CC.
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Carcinoma/metabolismo , Catepsinas/biossíntese , Regulação Enzimológica da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Metaloendopeptidases/biossíntese , Neoplasias do Colo do Útero/enzimologia , Catepsina F , DNA Complementar/metabolismo , Progressão da Doença , Feminino , Células HeLa , Humanos , Imuno-Histoquímica , Hibridização In Situ , Metaloproteinase 11 da Matriz , Metaloproteinase 12 da Matriz , Hibridização de Ácido Nucleico , Análise de Sequência com Séries de Oligonucleotídeos , Sondas de Oligonucleotídeos/química , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transcrição GênicaRESUMO
Objetivo. Evaluar la respuesta a bezafibrato en la dieta de sujetos con hipertensión arterial, hiperinsulinemia, hiperlipidemia mixta e hiperfibrinogenemia. Métodos. Se usó un diseño comparativo, doble ciego de placebo (N = 13) ó 400 mg/día de bezafibrato (N = 15) añadidos a una dieta hipolipémica pobre en azúcares refinados durante 90 días de tratamiento. Al inicio y al final del tratamiento se midieron fibrinógeno, lípidos, insulina y péotido C y se hizo una curva de tolerancia a la glucosa. Resultados. Los grupos fueron similares en edad, presión arterial e IMC. Al final de tratamiento hubo disminución de fibrinógeno, colesterol, triglicéridos y LDL-C en ambos grupos, pero sólo en el grupo de bezafibrato hubo: a) una disminución significativa de triglicéridos (64 mg/dL, p 0.01); y b) cambios marginales en fibrinógeno (disminuyó 35 mg/dL, p = 0.09), colesterol (disminuyó 26 mg/dL, p= 0.10) y en la relación glucosa/insulina (aumentó de 4.4 a 5.2, p= 0.09). El bezafibrato disminuyó ligeramente los niveles de insulina pero no afectó al péptido C. La correlación de los cambios de nivel de fibrinógeno versus la insulina de 60 min de la curva de tolerancia fue mayor en el grupo de bezafibrato (r = 0.61) que en el de placebo (r = 0.23). Conclusiones. En pacientes resistentes a insulina y con riesgo cardiovascular elevado, el bezafibrato y el placebo añadidos a una dieta hipolipémica disminuyeron el fibrinógeno plasmático. El bezafibrato bajó significativamente los niveles de triglicéridos en estos pacientes