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BACKGROUND: Exosome, a component of liquid biopsy, loaded protein, DNA, RNA and lipid gradually emerges as biomarker in tumors. However, exosomal circRNAs as biomarker and function mechanism in gastric cancer (GC) are not well understood. METHODS: Differentially expressed circRNAs in GC and healthy people were screened by database. The identification of hsa_circ_000200 was verified by RNase R and sequencing, and the expression of hsa_circ_000200 was evaluated using qRT-PCR. The biological function of hsa_circ_000200 in GC was verified in vitro. Western blot, RIP, RNA fluorescence in situ hybridization, and double luciferase assay were utilized to explore the potential mechanism of hsa_circ_000200. RESULTS: Hsa_circ_000200 up-regulated in GC tissue, serum and serum exosomes. Hsa_circ_000200 in serum exosomes showed better diagnostic ability than that of tissues and serum. Combined with clinicopathological parameters, its level was related to invasion depth, TNM staging, and distal metastasis. Functionally, knockdown of hsa_circ_000200 inhibited GC cells proliferation, migration and invasion in vitro, while its overexpression played the opposite role. Importantly, exosomes with up-regulated hsa_circ_000200 promoted the proliferation and migration of co-cultured GC cells. Mechanistically, hsa_circ_000200 acted as a "ceRNA" for miR-4659a/b-3p to increase HBEGF and TGF-ß/Smad expression, then promoted the development of GC. CONCLUSIONS: Our findings suggest that hsa_circ_000200 promotes the progression of GC through hsa_circ_000200/miR-4659a/b-3p/HBEGF axis and affecting the expression of TGF-ß/Smad. Serum exosomal hsa_circ_000200 may serve as a potential biomarker for GC.
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Tibet's ancient topography and its role in climatic and biotic evolution remain speculative due to a paucity of quantitative surface-height measurements through time and space, and sparse fossil records. However, newly discovered fossils from a present elevation of â¼4,850 m in central Tibet improve substantially our knowledge of the ancient Tibetan environment. The 70 plant fossil taxa so far recovered include the first occurrences of several modern Asian lineages and represent a Middle Eocene (â¼47 Mya) humid subtropical ecosystem. The fossils not only record the diverse composition of the ancient Tibetan biota, but also allow us to constrain the Middle Eocene land surface height in central Tibet to â¼1,500 ± 900 m, and quantify the prevailing thermal and hydrological regime. This "Shangri-La"-like ecosystem experienced monsoon seasonality with a mean annual temperature of â¼19 °C, and frosts were rare. It contained few Gondwanan taxa, yet was compositionally similar to contemporaneous floras in both North America and Europe. Our discovery quantifies a key part of Tibetan Paleogene topography and climate, and highlights the importance of Tibet in regard to the origin of modern Asian plant species and the evolution of global biodiversity.
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PREMISE: Microclimatic differences between the periphery and the interior of tree crowns result in a variety of adaptive leaf macromorphological and anatomical features. Our research was designed to reveal criteria for sun/shade leaf identification in two species of evergreen oaks, applicable to both modern and fossil leaves. We compared our results with those in other species similarly studied. METHODS: For both Quercus bambusifolia and Q. myrsinifolia (section Cyclobalanopsis), leaves from single mature trees with well-developed crowns were collected in the South China Botanical Garden, Guangzhou, China. We focus on leaf characters often preserved in fossil material. SVGm software was used for macromorphological measurement. Quantitative analyses were performed and box plots generated using R software with IDE Rstudio. Leaf cuticles were prepared using traditional botanical techniques. RESULTS: Principal characters for distinguishing shade and sun leaves in the studied oaks were identified as leaf lamina length to width ratio (L/W), and the degree of development of venation networks. For Q. myrsinifolia, shade and sun leaves differ in tooth morphology and the ratio of toothed lamina length to overall lamina length. The main epidermal characters are ordinary cell size and anticlinal wall outlines. For both species, plasticity within shade leaves exceeds that of sun leaves. CONCLUSIONS: Morphological responses to sun and shade in the examined oaks are similar to those in other plant genera, pointing to useful generalizations for recognizing common foliar polymorphisms that must be taken into account when determining the taxonomic position of both modern and fossil plants.
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Quercus , China , Folhas de Planta , Plantas , ÁrvoresRESUMO
The thelypteroid ferns are widely distributed across tropical regions around the world, but information about their fossil representatives is scarce. A new species, Cyclosorus scutum Naugolnykh, Wang, Han et Jin was discovered from the Eocene Changchang Formation of Hainan Island, South China, and is described on the basis of sterile and fertile leaves, sori, sporangia and spores preserved in situ. Discovery of this new species clearly shows that climatic conditions of that time in this area were humid, i.e. warm and wet.
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Clima , Gleiquênias/anatomia & histologia , Gleiquênias/fisiologia , Fósseis/anatomia & histologia , Dispersão Vegetal , China , Mudança Climática , Gleiquênias/classificaçãoRESUMO
A new species Camellia nanningensis was described on the basis of well-preserved mummified wood from the upper Oligocene Yongning Formation of Nanning Basin in Guangxi Province, South China. This represents the most ancient fossil wood assigned to Camellia, and the earliest fossil record of the family Theaceae in China. This fossil material shows that Camellia occurred in China as early as the late Oligocene, suggesting more ancient radiation of this genus than estimated by molecular dating.
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Camellia/anatomia & histologia , Fósseis , Madeira/anatomia & histologia , Ásia Oriental , Geografia , Especificidade da EspécieRESUMO
BACKGROUND: Postoperative urination dysfunction is a common complication after surgery in patients with cervical cancer. Portable bladder ultrasound are commonly utilized in clinical practice for measuring residual urine volume. This study aimed to the effect of bladder function training combined with portable ultrasound monitoring on bladder function recovery in patients with cervical cancer after training. METHODS: A total of 40 postoperative patients with cervical cancer were randomly divided into a control group (A) and an experimental group (B) of 20 cases each. Group A was given routine postoperative care, while group B was given bladder function training. Urgent urine bladder volume were taken twice daily after removal of the urinary catheter and monitored for five consecutive days. The difference of urgent urine bladder volume and bladder filling rate were compared by t-test and chi-square test respectively. The 36-item Short Form Health Survey (SF-36) was used to evaluate the quality of life of patients before and after intervention, and compared by Mann-Whitney U test. RESULTS: There was no significant difference in preoperative urgent urine volume between the two groups. After catheter removal, the bladder volume of patients in the B increased, while the bladder volume of patients in the A increased less and fluctuated greatly. The bladder filling rate in the A was significantly lower than that in the B (5/15 vs 17/18, p < 0.05). After intervention, the quality of life of the experimental group was better than that of the control group, including scores of general health, mental health, vitality, and physical role (p < 0.05). CONCLUSION: Postoperative cervical cancer patients trained to hold urine by portable ultrasound monitoring are able to recover bladder function.
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Liquidambar L. is a significant constituent of the Cenozoic flora in the Northern Hemisphere. Currently, this genus exhibits a discontinuous distribution across Asia and North America, with the center of diversity being in southeastern Asia. This study presents the first occurrence of Liquidambar in the Oligocene of South China. Fossil sweetgum infructescences, associated pollen, and leaves have been found in the Nanning Basin, Guangxi. A new species, Liquidambar nanningensis sp. nov., is described based on the morphological and anatomical characteristics of three-dimensionally preserved infructescences. The Liquidambar fossils from the Nanning Basin show a combination of features indicative of the former genera of Altingiaceae, Altingia, Liquidambar s. str., and Semiliquidambar. The new occurrence expands the taxonomic and morphological diversity of the Paleogene Liquidambar species in South China.
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Although it is well documented that mountains tend to exhibit high biodiversity, how geological processes affect the assemblage of montane floras is a matter of ongoing research. Here, we explore landform-specific differences among montane floras based on a dataset comprising 17,576 angiosperm species representing 140 Chinese mountain floras, which we define as the collection of all angiosperm species growing on a specific mountain. Our results show that igneous bedrock (granitic and karst-granitic landforms) is correlated with higher species richness and phylogenetic overdispersion, while the opposite is true for sedimentary bedrock (karst, Danxia, and desert landforms), which is correlated with phylogenetic clustering. Furthermore, we show that landform type was the primary determinant of the assembly of evolutionarily older species within floras, while climate was a greater determinant for younger species. Our study indicates that landform type not only affects montane species richness, but also contributes to the composition of montane floras. To explain the assembly and differentiation of mountain floras, we propose the 'floristic geo-lithology hypothesis', which highlights the role of bedrock and landform processes in montane floristic assembly and provides insights for future research on speciation, migration, and biodiversity in montane regions.
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Biodiversidade , Magnoliopsida , Filogenia , China , Magnoliopsida/crescimento & desenvolvimento , Altitude , Fenômenos Geológicos , EcossistemaRESUMO
Anatomical structure of mummified wood of Cryptocarya (Lauraceae) from the Upper Pleistocene of Maoming, South China and the woods of 15 extant species of Cryptocarya from China and Malaysia were examined. The fossil wood has been convincingly attributed to extant species Cryptocarya chinensis (Hance) Hemsl. This is the first reliable fossil record of Cryptocarya in Asia. The finding combined with the results of Biomod2 species distribution modeling suggest that the range of C. chinensis in the Late Pleistocene in South China and North Vietnam was very restricted due to increased continental aridity and enhanced temperature seasonality in this region. Thus, modern populations of C. chinensis in Maoming can be considered as glacial relicts. The mines (larval tunnels) produced by the larvae of flies from the genus Phytobia Lioy (Agromyzidae, Diptera) were observed in fossil wood under study. These cambial miners have never been reported in Cryptocarya.
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Quercus is the largest genus within the Fagaceae and has a rich fossil record. Most of the fossil material is attributed to the subgenus Quercus based on leaves, pollen or rarely acorns and nuts. Fossil records of Q. section Cyclobalanopsis characterized by ring-cupped acorns are relatively few and especially those described based on nuts are scant. In this study, we described four new species of Quercus section Cyclobalanopsis based on mummified acorns and nuts: Q. paleodisciformis X.Y. Liu et J.H. Jin sp. nov., Q. paleohui X.Y. Liu et J.H. Jin sp. nov., Q. nanningensis X.Y. Liu et J.H. Jin sp. nov. and Q. yongningensis X.Y. Liu et J.H. Jin sp. nov. These species closely resemble the extant species Q. disciformis, Q. hui, Q. kerrii, and Q. dinghuensis. The occurrence of Q. section Cyclobalanopsis in the Oligocene stratum of Guangxi, South China, suggests that the section has diversified within its extant distribution center since the Oligocene. By combining records from other areas, we propose that the section first appeared in the middle Eocene of East Asia (Sino-Japan), has diversified in situ with a few elements scattering into West Asia and southern Europe since the Oligocene and Pliocene, respectively, and finally became restricted in East Asia since the Pleistocene. This indicates that the section originated and diversified in East Asia, before spreading into West Asia no later than the Oligocene and into southern Europe by the Pliocene. Subsequently it disappeared from South Europe and West Asia due to the appearance of the (summer dry) Mediterranean climate and widespread cooling during the Pleistocene.
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Objective: To investigate the effect of different bladder filling states on positioning errors in radiotherapy for cervical cancer and obtain the reference range of bladder filling consistency during radiotherapy.Methods: Patients who underwent postoperative radiotherapy for cervical cancer in Nantong Tumor Hospital from October 2018 to December 2019 were selected. According to the bladder filling deviation, they were divided into group A1 (deviation < 20%) and group B1 (deviation ≥ 20%). The bladder filling variations of the two groups were compared with different positioning errors. Group A2 has a positioning error of <0.4 cm, and group B2 has a positioning error of ≥0.4 cm. The reference range of bladder filling consistency during radiotherapy is obtained by analyzing the composition ratio of different positioning errors of bladder filling deviation.Results: This study included 195 patients with cervical cancer. The error of longitudinal and vertical position in group B1 was significantly higher than that in group A1 (0.50 ± 0.34 vs. 0.26 ± 0.22 cm, p < 0.001, and 0.22 ± 0.17 vs. 0.16 ± 0.12 cm, p < 0.001). Compared with group B2, the absolute deviation of bladder filling in group A2 (54.1% ± 54.4% vs. 25.6% ± 22.7%, p < 0.001) was slight. The chi-square test showed significant differences in the proportion of the positioning state of different bladder filling forms (χ2 = 31.006, p < 0.001). In addition, there was a significant difference in the proportion of stability errors in patients with poor stability in different directions (χ2 = 118.551, p < 0.001).Conclusion: In patients with cervical cancer fixed in the supine position, a bladder capacity deviation <20% is easier to achieve excellent positioning with, and it can better control the positioning error of radiotherapy and ensure the positioning accuracy of dose distribution to the target area. It can also achieve good tumor treatment effects. This range can be used as a reference for bladder filling consistency in patients with cervical cancer undergoing radiotherapy.
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Neoplasias do Colo do Útero , Feminino , Humanos , Neoplasias do Colo do Útero/radioterapia , Neoplasias do Colo do Útero/cirurgia , Bexiga Urinária/cirurgia , Histerectomia , Valores de ReferênciaRESUMO
OBJECTIVE: To observe the changes of sex hormones and sexual function in male patients with Graves' disease (GD) after Radioiodine-131 (I-131) therapy. METHODS: Thirty-four male GD patients, aged 21 -40 (32.3 +/- 6.7) years, were treated with I-131 at the dose of 111 - 407 (237.8 +/- 51.8) MBq. The levels of serum sex hormones were measured, and the patients'scores on erectile function (IIEF-5) were obtained before and 3 and 6 months after the treatment. Another 20 healthy men aged 25 - 37 (31 +/- 3.1) years were enlisted as controls. RESULTS: The baseline levels of estrogen (E2), testosterone (T) and luteinizing hormone (LH) were (132.5 +/- 40.4) pmol/L, (21.6 +/- 4.6) nmol/L and (10.1 +/- 4.4) IU/L in the GD patients, significantly higher than (80.4 +/- 31.2) pmol/L, (14.5 +/- 4.2) nmol/L and (6.2 +/- 1.9) IU/L in the healthy controls (P < 0.05). The E2, T and LH levels showed a significant decrease in the GD patients after 3 months of treatment ([110.2 +/- 20.6] pmol/L, [17.7 +/- 5.5] nmol/L and (9.4 +/- 3.9) IU/L, P < 0.05), but exhibited no statistically significant differences from the healthy controls at 6 months ([82.6 +/- 30.1] pmol/L, [13.8 +/- 3.4 ] nmol/L and [6.6 +/- 1.5] IU/L, P > 0.05). The IIEF-5 score of the GD patients was 5 - 25 (15.5 +/- 3.5) before I-131 treatment, significantly lower than that of the controls (19 - 25, 24 +/- 0.5) (P < 0.05), and it was 8 - 25 (19.5 +/- 1.0) at 3 months and 10 - 25 (23.5 +/- 1.5) at 6 months, significantly higher in the latter than in the former (P < 0.05), and with no significant difference between the 6-month treated patients and the healthy controls (P > 0.05). CONCLUSION: The E2, T and LH levels are increased while the IIEF-5 score decreased markedly in male GD patients. Six-month treatment with I-131 can not only restore the E2, T and LH levels to normal but also significantly improve the patient's sexual function.
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Estrogênios/sangue , Doença de Graves/sangue , Doença de Graves/terapia , Radioisótopos do Iodo/uso terapêutico , Testosterona/sangue , Adulto , Estudos de Casos e Controles , Hormônio Foliculoestimulante/sangue , Humanos , Hormônio Luteinizante/sangue , Masculino , Adulto JovemRESUMO
The genus Woodwardia, which together with the genera Anchistea and Lorinseria comprise the subfamily Woodwardioideae of Blechnaceae, has a disjunct distribution across Central and North America, Europe and the temperate to tropical areas of Asia. Fossil records of Woodwardia occur throughout the Paleogene and Neogene of North America, Europe and Asia. However, well-preserved fertile pinna fossils of this genus have not yet been reported in South China. In this paper, a new species, W. changchangensis Naugolnykh et Song, sp. nov. is described from the middle Eocene of the Changchang Basin, Hainan Island, South China. Macromorphological and micromorphological features of the fertile pinna show a straight pinna rachis, alternate, subtriangular pinnules, acute pinnule apices, almost entire or slightly undulate pinnule margins, long-ovoid sori, stalked sporangia and spores with wing-like folds on the surface, which are characterised in detail. Overall, the present fossil is most similar to the extant species Woodwardia japonica, which mostly grows in warm and moist environments. The discovery of this new species from the Changchang Basin of Hainan Island indicates that this genus has been distributed in the low-latitude tropical regions of South China from as early as the middle Eocene. Based on this find, and previous studies of other ferns from the same site, we infer that the climate of the Palaeo-Hainan landscape during deposition of the Changchang Formation was warm and humid, similar to conditions prevailing today across this region.
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The new species Eriobotryacrassifolia, collected from Yunnan Province, China, is characterised and illustrated. A phylogeny based on chloroplast genomes supported its closest affinity with E.tengyuehensis, while a phylogeny based on 197 single-copy nuclear genes supported its closest affinity with E.fragrans and E.deflexa. Morphologically, however, it resembles E.angustissima. Nevertheless, it can be easily distinguished from E.angustissima by its abaxially retroflexed and sharply serrate leaf margins, densely rusty tomentose inflorescences, and oblong or elliptic leaves.
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Cycas is often considered a living fossil, thereby providing a unique model for revealing the evolution of spermatophytes. To date, the genetic inheritance of these archaic plants is not fully understood. The present study seeks to document the process of organelle inheritance in an interspecific cross of Cycas species. Extranuclear organelle DNA from chloroplasts and mitochondria was analyzed using both polymerase chain reaction-restriction fragment length polymorphism analysis and microscopy. Here, we show that the chloroplasts and mitochondria in the progeny of interspecific crosses between Cycas taitungensis and Cycas ferruginea were exclusively inherited from the female parent. Epifluorescence microscopic analyses of the pollen cells from Cycas elongata indicated that there was a significant degradation of organelle DNA in male reproductive cells following maturation; the DNA fluorescent signals were only seen after pollen mitosis two, but not detectable at mature stage. Lack of organelle DNA fluorescent signal in prothallial cells was confirmed by the absence of plastids and mitochondria in electronic microscopic images. In conclusion, these data suggest that the maternal plastid and mitochondrial inheritance in Cycas, native to the old world, are the same as seen in seed plants.
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Cruzamentos Genéticos , Cycas/genética , Padrões de Herança , Mitocôndrias/genética , Plastídeos/genética , Evolução Biológica , Cycas/ultraestrutura , DNA Mitocondrial , DNA de Plantas , Microscopia Eletrônica , OrganelasRESUMO
OBJECTIVE: To explore the expression of phosphatase and tensin homolog deleted on chromosome ten (PTEN) in low rectal cancer on neoadjuvant chemoradiotherapy with capecitabine plus radiotherapy. METHODS: Sixty-six patients with low rectal cancer on therapy with capecitabine (1650 mg×m(-2)×d(-1) in 2 divided doses) for two course and concurrent radiotherapy (50 Gy, 2 Gy/day, 5 days a week). Then the investigators analyzed the relationship between the preoperative neoadjuvant chemoradiotherapy and prognosis and measured the expression of PTEN during neoadjuvant chemoradiotherapy. RESULTS: 92.4% (61/66) of patients received neoadjuvant chemoradiotherapy as planned. 87.9% (58/66) tumor stages were down-staged, tumor size decreased while the distance from anal edge increased. And curative resection with sphincter-sparing was carried out in all patients. The rate of sphincter preservation was 90.9% (60/66). Among which, 85.5% patients showed an excellent function of sphincter. The 2-year survival rate was 87.9% (58/66). The survival period was an average of 35.3 months (range: 25-60). The PTEN mRNA and protein expression in cancer tissues on neoadjuvant chemoradiotherapy were significantly higher than those before neoadjuvant chemoradiotherapy (P=0.0079, 0.0269). CONCLUSIONS: The preoperative neoadjuvant chemoradiotherapy in lower rectal cancer patients has shown its efficacy in down-staging cancer, enhancing resectability, offering sphincter preservation, up-regulating PTEN expression, promoting the apoptosis of cancer cell and achieving a better survival rate. Thus preoperative neoadjuvant chemoradiotherapy is an effective adjuvant measure.
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Terapia Neoadjuvante , PTEN Fosfo-Hidrolase/metabolismo , Neoplasias Retais/metabolismo , Adulto , Idoso , Quimioterapia Adjuvante , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Radioterapia Adjuvante , Neoplasias Retais/tratamento farmacológico , Neoplasias Retais/radioterapiaRESUMO
We demonstrate with morphological characters that the species Pterostyrax burmanicus W.W.Sm. & Farrer and Parastyrax macrophyllus C.Y.Wu & K.M.Feng (Styracaceae) are best placed in the genus Rehderodendron Hu. Rehderodendron burmanicum (W.W.Sm. & Farrer) W.Y.Zhao, P.W.Fritsch & W.B.Liao, comb. nov. and Rehderodendron macrophyllum (C.Y.Wu & K.M.Feng) W.Y.Zhao, P.W.Fritsch & W.B.Liao, comb. nov., are created. We also provide a lectotype for R. macrophyllum. These revisions result in the reduction of Pterostyrax Siebold & Zucc. to three species and this genus is no longer considered to be documented from Myanmar. Further, Parastyrax W.W.Sm. becomes a monotypic genus comprising only P. lacei (W.W.Sm.) W.W.Sm., distributed in Kachin State, northeast Myanmar and Yunnan Province, south-western China.
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Saxifraga damingshanensis (Saxifragaceae), a new species from Damingshan Nature Reserve in Guangxi Province, is described and illustrated. A morphological comparison between the new species and its putative relatives, S. mengtzeana and S. luoxiaoensis, is presented. The new species is morphologically similar to S. mengtzeana, but it can be easily distinguished by its non-peltate leaf, both surfaces of mature leaf blade covered with white glandular trichome, petals 3-veined and margin entire. Phylogenetic analysis, based on two chloroplast DNA regions (matK and psbA-trnH), confirmed that the new species belongs to S. sect. Irregulares. The new species is currently only known from Damingshan, Guangxi and we assign it an IUCN Red List preliminary status as Data Deficient.
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Cervical cancer is one of the most common malignant carcinomas in the female reproductive system. Long non-coding RNAs (lncRNAs) have been verified to participate in the tumorigenesis of cervical cancer. In present study, we investigate the role of lncRNA XLOC_008466 in the occurrence and progression of cervical cancer. Results showed that XLOC_008466 expression was up-regulated in cervical cancer tissue and cells compared to normal controls. In vitro functional experiments, CCK-8 assay and colony formation assay showed that XLOC_008466 knockdown suppressed the proliferation of cervical cancer cells. Flow cytometry and transwell assay showed that XLOC_008466 knockdown induced G0/G1 phase arrest and aggravated the apoptosis. In vivo, XLOC_008466 knockdown inhibited the tumor growth. Bioinformatics analysis revealed that XLOC_008466 sponged miR-216b with the complementary binding sites at 3'-UTR. Overall, our study reveals the tumor promoting role of XLOC_008466 in cervical cancer carcinogenesis, providing a novel molecular mechanism and therapeutic target for cervical cancer.
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Carcinogênese/genética , RNA Longo não Codificante/genética , Neoplasias do Colo do Útero/genética , Neoplasias do Colo do Útero/patologia , Regiões 3' não Traduzidas/genética , Animais , Apoptose/genética , Pontos de Checagem do Ciclo Celular/genética , Linhagem Celular Tumoral , Proliferação de Células/genética , Feminino , Fase G1/genética , Células HeLa , Humanos , Camundongos , Camundongos Nus , Fase de Repouso do Ciclo Celular/genética , Regulação para Cima/genéticaRESUMO
The genus Schima includes about 20 species and is distributed only in southern China and adjacent areas of Asia. The previous molecular phylogenetic analysis suggested Schima is in the tribe Gordoniae, along with Gordonia and Franklinia. However, because few fossils have been reported, the biogeographic origin of Schima is still poorly known. In this paper mummified fossil fruits of Schima are described from the upper Oligocene Yongning Formation of the Nanning Basin, Guangxi, South China. In gross morphology, the new fossil species, Schima kwangsiensis, is similar to the extant S. superba by its pentacarpellate, loculicidally dehiscent capsules, 5 imbricate sepals, pedicels with bracteoles and marginally winged seeds. Due to its excellent preservation, the new species may provide sufficient details for understanding the early evolutionary and phytogeographic history of the genus. Morphological clustering analysis shows that the new fossil species is closely related to two extant species (S. wallichii and S. superba) in the genus, implying that they may belong to an ancient taxon that occurs earlier than the others. More importantly, this discovery represents the earliest record of this genus in Asia and it explicitly moves the fossil record back to the late Oligocene in this region.