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1.
Artículo en Inglés | MEDLINE | ID: mdl-38570918

RESUMEN

CONTEXT: Medullary thyroid cancer (MTC) often exhibits aggressive growth with distant organ metastasis, leading to poor survival. OBJECTIVE: The question of whether primary tumor resection (PTR) is beneficial for patients with metastatic MTC remains a subject of debate. In this study, we evaluated the prognostic significance of organ-specific metastases and the number of metastatic organs in these patients, and we also conducted an analysis to determine the therapeutic value of PTR in managing this rare malignancy. MATERIALS AND METHODS: Patients initially diagnosed with metastatic MTC were identified within the Surveillance, Epidemiology, and End Results (SEER) database. Univariable and multivariable Cox proportional hazards regression models were performed to identify survival predictors. Survival outcomes were calculated using the Kaplan-Meier method and compared using the log-rank tests. RESULTS: A total of 186 patients with metastatic MTC at initial diagnosis from 2010 to 2020 were included. Bone, lung and liver were the most common metastatic organs. Patients with brain metastasis had significantly worse overall survival (OS) (p = 0.007) and cancer-specific survival (CSS) (p = 0.0013). Among all patients, 105 (56.45%) underwent PTR, and this group showed reduced overall mortality (OM) and cancer-specific mortality (CSM) (all p < 0.05). When analyzing different metastatic patterns, PTR significantly lowered the risk of OM and CSM for patients with bone, lung, liver, or distant lymph node (DLN) involvement (all p < 0.05). Additionally, among patients with one or two metastases, those undergoing surgical resection were significantly associated with favorable OS (p = 0.008) and CSS (p = 0.0247). CONCLUSIONS: PTR may confer therapeutic benefits for carefully selected individuals with metastatic MTCs. To integrate these insights into clinical decision-making settings, it is imperative to undertake multicenter prospective studies in the future.

2.
Huan Jing Ke Xue ; 44(4): 2083-2092, 2023 Apr 08.
Artículo en Chino | MEDLINE | ID: mdl-37040958

RESUMEN

Environmental heterogeneity can not only increase species diversity to some extent but also affect the stability of terrestrial communities. However, how environmental heterogeneity affects species diversity of epilithic diatom communities in aquatic ecosystems is rarely reported. In this study, therefore, epilithic diatoms and their roles in driving species diversity were explored by quantifying and comparing the environmental heterogeneity in Xiangxi River, a tributary of the Three Gorges Reservoir Area (TGR), on a time scale. The results showed that environmental heterogeneity, taxonomic ß-diversity, and functional ß-diversity in non-impoundment periods were significantly higher than those in impoundment periods. Moreover, the turnover components in the two hydrological periods showed the highest contribution to ß-diversity. However, the taxonomic α-diversity in impoundment periods was significantly higher than that in non-impoundment periods. In addition, functional richness in functional α-diversity was significantly higher in non-impoundment periods than that in impoundment periods, whereas there was no significant difference in other functional α-diversity, i.e., functional dispersion and functional evenness, found between the two periods. Multiple regression on (dis)similarity matrices (MRM) analysis indicated that ammonium nitrogen (NH4+-N) and silicate (SiO32--Si) were the key environmental heterogeneous factors affecting the epilithic diatom community in Xiangxi River during the non-impoundment periods, whereas the key heterogeneous factors were ammonium nitrogen (NH4+-N), silicate (SiO32--Si), and total phosphorus (TP) during the impoundment periods. These results suggested that the environmental heterogeneity during different hydrological periods in TGR can significantly affect the community structure of epilithic diatoms, resulting in the differentiation of species within the community and even affecting the stability of aquatic ecosystems.


Asunto(s)
Diatomeas , Ríos , Ecosistema , Monitoreo del Ambiente/métodos , Nitrógeno/análisis
3.
Huan Jing Ke Xue ; 44(2): 857-867, 2023 Feb 08.
Artículo en Chino | MEDLINE | ID: mdl-36775609

RESUMEN

In order to investigate the relationship between phytoplankton community functional group compositions and resource use efficiency in important tributaries of the Three Gorges Reservoir, phytoplankton and environment parameters were sampled from five tributaries, the Xiangxi River, Daning River, Meixi River, Pengxi River, and Huangjin River, in August and November, 2020. There were 119 species (variants) belonging to 62 genera and 7 phyla identified in summer, whereas 118 species (variants) belonging to 7 divisions of 58 genera were found in winter. According to Padisak's theory, all phytoplankton were divided into 25 functional groups, of which there were six important functional groups in both summer and winter:L0, H1, D, Y, MP, and P in summer and L0, H1, A, M, MP, and Y in winter. The α-diversity of the phytoplankton functional group in summer was higher than that in winter. Moreover, a higher α-diversity was also found in downstream samples relative to that in upstream samples, indicating that the community structure was more complex, and the community stability was relatively better in downstream regions of the rivers. Redundancy analysis (RDA) showed that the environment factors, i.e., ν, pH, permanganate index, WT, and RUETN, significantly affected phytoplankton functional groups (P<0.05). Variance partitioning analysis (VPA) indicated that environmental factors had a higher explanatory degree for the change in functional group composition in summer (45.23%); on the contrary, resource use efficiency had a higher explanatory degree in winter (42.33%). The linear fitted model showed that functional groups L0, H1, D, and Y showed a significant positive correlation relationship with RUETN and RUETP in summer, whereas only four functional groups (M, MP, Y, and A) had a linear relationship with RUETP, and all function groups had a good linear relationship with RUETN in winter. These results indicated that the functional groups belonging to cyanobacteria, dinoflagellates, and cryptophyta were more efficient at using limited resources in summer, whereas the diatoms had a good linear relationship with resource use efficiency and formed a dominant group in the low temperature environment of winter. These results suggest that the impounding of the Three Gorges Reservoir area can significantly change the resource use efficiency of phytoplankton, resulting in changes in the phytoplankton functional group composition and community structure.


Asunto(s)
Cianobacterias , Diatomeas , Fitoplancton , Monitoreo del Ambiente/métodos , Fósforo/análisis , Estaciones del Año , China
4.
Huan Jing Ke Xue ; 43(10): 4480-4488, 2022 Oct 08.
Artículo en Chino | MEDLINE | ID: mdl-36224134

RESUMEN

The succession of dominant species always occurs during cyanobacterial blooms because there are certain conditions for cyanobacterial blooms formed by different cyanobacteria; this results in more uncertain and complex effects in cyanobacterial blooms. However, the succession pattern and consequences of dominant species and its driving factors have not received enough attention during cyanobacteria blooms. In this study, the phytoplankton community characteristics and water environment factors of Nanpeng Reservoir, a drinking water source in Chongqing, were monitored and analyzed from April to September 2018. The results showed that:① a total of 108 species of phytoplankton belonging to 59 genera and 8 phyla were identified in Nanpeng Reservoir. Of this, 13 species of 4 phyla were identified as dominant species, among which the dominance index of Cylindrospermopsis raciborskii was the highest, followed by that of Pseudoanabaena sp. ② The most dominant cyanobacteria were Pseudoanabaena and Cylindrospermopsis in May and July, respectively, in which cyanobacteria density peaked, whereas the Shannon-Weiner diversity and Pielou evenness were significantly lower than those in the other months. ③ NMDS results showed that the correlation between Cylindrospermopsis or Pseudoanabaena and the ambient phytoplankton community was 0.58 and 0.48, respectively. Moreover, the VPA results showed that 47.51% of the community variation could be explained by environmental factors, and only 12.04% and 12.74% of variation in community composition could be explained by Cylindrospermopsis and Pseudoanabaena, respectively. ④ The abundance of Cylindrospermopsis was significantly positively affected by WT, pH, and RUEN and negatively affected by SD and RUEP. However, the abundance of Pseudoanabaena was significantly positively affected by permanganate index and negatively affected by EC and DO. These results suggested that both dominating cyanobacteria had significant effects on the surrounding phytoplankton community. Relative to that of Pseudoanabaena, however, Cylindrospermopsis had a more obvious impact on the aquatic ecosystem. Moreover, the synergistic effect of N limitation and warming of the water column may have caused the replacement of Pseudoanabaena with Cylindrospermopsis to form a dominant population.


Asunto(s)
Cianobacterias , Agua Potable , Ecosistema , Eutrofización , Fitoplancton
5.
Minim Invasive Ther Allied Technol ; 30(1): 12-20, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31597487

RESUMEN

INTRODUCTION: Microwaves (MWs) quickly deliver relatively high temperatures into tumors and cover a large ablation zone. We present a research protocol for using water-cooled double-needle MW ablation arrays for tumor ablation here. MATERIAL AND METHODS: Our research program includes computer modeling, tissue-mimicking phantom experiments, and in vitro swine liver experiments. The computer modeling is based on the finite element method (FEM) to evaluate ablation temperature distributions. In tissue-mimicking phantom and in vitro swine liver ablation experiments, the performances of the new device and the single-needle MW device currently used in clinical practice are compared. RESULTS: FEM shows that the maximum transverse ablation diameter (MTAD) is 4.2 cm at 100 W output and 300 s (assessed at the 50 °C isotherm). In the tissue-mimicking phantom, the MTDA is 2.6 cm at 50 W and 300 s in single-needle MW ablation, and 4 cm in double needle MW ablation array. In in vitro swine liver experiments, the MTAD is 2.820 ± 0.127 cm at 100 W and 300 s in single-needle MW ablation, and 3.847 ± 0.103 cm in MW ablation array. CONCLUSION: A new type of water-cooled MW ablation array is designed and tested, and has potential advantages over currently used devices.


Asunto(s)
Ablación por Catéter , Microondas , Animales , Computadores , Hígado/cirugía , Porcinos , Agua
6.
PLoS Genet ; 16(2): e1008300, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-32092051

RESUMEN

Craniofrontonasal syndrome (CFNS) is a rare X-linked disorder characterized by craniofacial, skeletal, and neurological anomalies and is caused by mutations in EFNB1. Heterozygous females are more severely affected by CFNS than hemizygous males, a phenomenon called cellular interference that results from EPHRIN-B1 mosaicism. In Efnb1 heterozygous mice, mosaicism for EPHRIN-B1 results in cell sorting and more severe phenotypes than Efnb1 hemizygous males, but how craniofacial dysmorphology arises from cell segregation is unknown and CFNS etiology therefore remains poorly understood. Here, we couple geometric morphometric techniques with temporal and spatial interrogation of embryonic cell segregation in mouse mutant models to elucidate mechanisms underlying CFNS pathogenesis. By generating EPHRIN-B1 mosaicism at different developmental timepoints and in specific cell populations, we find that EPHRIN-B1 regulates cell segregation independently in early neural development and later in craniofacial development, correlating with the emergence of quantitative differences in face shape. Whereas specific craniofacial shape changes are qualitatively similar in Efnb1 heterozygous and hemizygous mutant embryos, heterozygous embryos are quantitatively more severely affected, indicating that Efnb1 mosaicism exacerbates loss of function phenotypes rather than having a neomorphic effect. Notably, neural tissue-specific disruption of Efnb1 does not appear to contribute to CFNS craniofacial dysmorphology, but its disruption within neural crest cell-derived mesenchyme results in phenotypes very similar to widespread loss. EPHRIN-B1 can bind and signal with EPHB1, EPHB2, and EPHB3 receptor tyrosine kinases, but the signaling partner(s) relevant to CFNS are unknown. Geometric morphometric analysis of an allelic series of Ephb1; Ephb2; Ephb3 mutant embryos indicates that EPHB2 and EPHB3 are key receptors mediating Efnb1 hemizygous-like phenotypes, but the complete loss of EPHB1-3 does not fully recapitulate the severity of CFNS-like Efnb1 heterozygosity. Finally, by generating Efnb1+/Δ; Ephb1; Ephb2; Ephb3 quadruple knockout mice, we determine how modulating cumulative receptor activity influences cell segregation in craniofacial development and find that while EPHB2 and EPHB3 play an important role in craniofacial cell segregation, EPHB1 is more important for cell segregation in the brain; surprisingly, complete loss of EPHB1-EPHB3 does not completely abrogate cell segregation. Together, these data advance our understanding of the etiology and signaling interactions underlying CFNS dysmorphology.


Asunto(s)
Movimiento Celular/genética , Anomalías Craneofaciales/genética , Efrina-B1/genética , Cresta Neural/embriología , Cráneo/anomalías , Animales , Anomalías Craneofaciales/diagnóstico , Modelos Animales de Enfermedad , Embrión de Mamíferos , Desarrollo Embrionario/genética , Efrina-B1/metabolismo , Femenino , Heterocigoto , Humanos , Masculino , Ratones , Ratones Noqueados , Mosaicismo , Mutación , Cresta Neural/citología , Fenotipo , Receptores de la Familia Eph/genética , Receptores de la Familia Eph/metabolismo , Índice de Severidad de la Enfermedad , Factores Sexuales , Cráneo/embriología , Cromosoma X/genética
7.
Int J Ophthalmol ; 12(11): 1731-1736, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31741862

RESUMEN

AIM: To investigate the clinical features, treatment and prognosis of primary ocular adnexal mucosa-associated lymphoid tissue lymphoma (POAML). METHODS: A retrospective analysis was performed on 64 patients with POAML who were admitted to the First Affiliated Hospital of Zhengzhou University from January 2006 to December 2018. RESULTS: With a median follow-up of 61mo (range, 2-156mo), estimated overall survival (OS) rate and progression-free survival (PFS) rate at 10y reached 94.5% and 61.5%, respectively. Median OS time and PFS time were not reached. During this period, only 3 patients died, but none of them died directly due to disease progression. One patient (1.6%) developed transformation to diffuse large B-cell lymphoma (DLBCL). Of the 56 patients achieved complete remission after first-line treatment, 5 (8.9%) developed local and/or systemic relapse eventually. Patients ≥60y had significantly shorter PFS than younger patients (P=0.01). For patients with early stages (Ann Arbor stage I and stage II), univariate analysis confirmed that radiotherapy dose lower than 32 Gy were independently associated with shorter PFS (P=0.04). Other factors including gender, bone marrow involvement, the initial location of the disease, and the laterality were not associated with PFS. CONCLUSION: The data from our center indicate that POAML has a slow clinical progression and has an excellent clinical outcome. Patients with POAML harbor a continual risk of relaps and transformation to aggressive subtype of lymphoma.

8.
Mar Biotechnol (NY) ; 21(2): 206-216, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30632018

RESUMEN

Knowledge on sex determination has proven valuable for commercial production of the prawn Macrobrachium rosenbergii due to sex dimorphism of the male and female individuals. Previous studies indicated that prawn sex is determined by a ZW-ZZ chromosomal system, but no genomic information is available for the sex chromosome. Herein, we constructed a genomic bacterial artificial chromosome (BAC) library and identified the ZW-derived BAC clones for initial analysis of the sex chromosomal DNA sequence. The arrayed BAC library contains 200,448 clones with average insert size of 115.4 kb, corresponding to ∼ 4× coverage of the estimated 5.38 Gb genome. Based on a short female-specific marker, a Z- and a W-fragment were retrieved with the genomic walking method. Screening the BAC library using a ZW-specific marker as probe resulted in 12 positive clones. From these, a Z-derived (P331M17) and a W-derived (P122G2) BAC clones were randomly selected and sequenced by PacBio method. We report the construction of a large insert, deep-coverage, and high-quality BAC library for M. rosenbergii that provides a useful resource for positional cloning of target genes, genomic organization, and comparative genomics analysis. Our study not only confirmed the ZW/ZZ system but also discovered sex-linked genes on ZW chromosomes for the first time, contributing to a comprehensive understanding of the genomic structure of sex chromosomes in M. rosenbergii.


Asunto(s)
Cromosomas Artificiales Bacterianos , Palaemonidae/genética , Cromosomas Sexuales/genética , Animales , Femenino , Biblioteca Genómica , Masculino , Análisis de Secuencia de ADN , Procesos de Determinación del Sexo
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