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1.
Plant Divers ; 44(3): 290-299, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35769593

RESUMO

Delimiting species requires multiple sources of evidence. Here, we delimited two varieties of Halenia elliptica (Gentianaceae) using several lines of evidence, including morphological traits and mating system in a sympatric population, phylogenetic relationships based on nrITS and cpDNA (rpl16) data, and complete chloroplast genome sequences. Comparative analysis of 21 morphological traits clearly separates the two varieties of H. elliptica. Examination of the flowering process and pollination treatments indicate that H. elliptica var. grandiflora produces seeds via outcrossing, whereas H. elliptica var. elliptica produces seeds via mixed mating. Furthermore, hand-pollinated hybridization of the two varieties produced no seeds. Observations of pollinators showed that when bees began a pollination bout on H. elliptica var. grandiflora they preferred to continue pollinating this variety; however, when they began a pollination bout on H. elliptica var. elliptica, they showed no preference for either variety. Phylogenetic analysis confirmed the monophyly of H. elliptica, which was further divided into two monophyletic clades corresponding to the two varieties. A large number of variants from the chloroplast genomes reflected remarkable genetic dissimilarities between the two varieties of H. elliptica. We recommend that the two varieties of H. elliptica should be revised as two species (H. elliptica and H. grandiflora). Our findings indicate that H. elliptica varieties may have split into two separate species due to a shift in mating system, changes in flowering phenology and/or post-pollination reproductive isolation.

2.
Evol Bioinform Online ; 16: 1176934320908261, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32127748

RESUMO

Understanding the evolution of flower diversity is a central topic in plant evolutionary ecology, and natural selection on floral traits via male fitness could be estimated quantitatively using microsatellites. Here, based on RNA sequencing, we developed simple sequence repeat primers and verified polymorphisms in 2 wild populations of Herpetospermum pedunculosum (Cucurbitaceae), a dioecious annual plants native to the Himalaya Mountains. A total of 131 paired primers were designed; 15 paired primers were found to be polymorphic, with the expected heterozygosity varying between 0.280 and 0.767. We also identified 58 genotypes in 20 plants from the 2 populations. Conclusively, these primers could be effective in examining male fitness and population genetic structure of H pedunculosum in future studies.

3.
Front Genet ; 9: 223, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29988524

RESUMO

Halenia (Gentianaceae) originated from the mountain regions of East Asia, and diversified in America following long migrations via Beringia. While Halenia elliptica, one species of the genus in China, migrated toward high latitudes in China. Spur length of H. elliptica is highly variable. We examined the relationship between spur length and mating pattern along a latitude gradient. Field experiments were performed in two populations of H. elliptica, and we found that this species could produce seeds via both autonomous selfing and the aid of pollinators, suggesting a mixed mating system. In seven populations of H. elliptica along a latitudinal gradient, we found a trend of decrease in spur length with the increase of latitude. Based on molecular data from 11 microsatellite loci, we found that multilocus outcrossing rate decreased with the increase of latitude while the estimated inbreeding depression increased significantly, indicating that a high degree of inbreeding depression might have prevented evolution toward complete selfing in the high latitude populations with short spur length, and thus maintained mixed mating system of H. elliptica. Our results suggest that the mixed mating system of this species might be helpful in overcoming pollinator scarcity in newly colonized populations toward high latitudes after its origination in the mountain regions of China, and the decrease of spur length in the high latitude populations could result from reduced resource allocation to pollinator associated traits.

4.
Sci Rep ; 7: 42466, 2017 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-28195162

RESUMO

Climatic tolerance, especially drought tolerance, is one of the major factors shaping the geographic distributions of plant species. Thus, the general decline in rainfall from the Himalaya-Hengduan Mountains (HHM) to the inner Qinghai-Tibet Plateau (QTP) might account for the significant differences in species distributions and richness between the two regions. To test this hypothesis, we conducted a water stress experiment using four Anisodus species (A. tanguticus, A. luridus, A. carniolicoides and A. acutangulus), which were treated with different levels of water stress in a glasshouse, and examined their differences in physiological responses. The results suggest that A. tanguticus, which inhabits the inner QTP, generally has higher fitness under severe water stress than the other species based on its high root:shoot ratio, long-term water use efficiency and photosynthetic rate, indicating that it possesses a genetically based drought tolerance mechanism. Our results suggest that plant species inhabiting the inner QTP may be more drought tolerant than those inhabiting the HHM regions. This provides a new example supporting the hypothesis that climatic tolerance plays a major role in shaping plant distributions on the QTP and its adjacent highlands and presents new insights into the patterns of geographic distribution and diversity of the plants inhabiting these areas.


Assuntos
Adaptação Biológica , Secas , Meio Ambiente , Solanaceae/fisiologia , Estresse Fisiológico , Biomassa , Clorofila/metabolismo , Nitrogênio/metabolismo , Característica Quantitativa Herdável , Solo/química , Tibet , Água
5.
J Exp Clin Cancer Res ; 28: 70, 2009 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-19476635

RESUMO

BACKGROUND: Insulin-like growth factor binding protein (IGFBPs) have been as potential tumor suppressors in the occurrence and development of tumors. Cellular Fas-associated death domain-like interleukin-1beta-converting enzyme (FLICE)-like inhibitory protein (cFLIP) contains a death effect domain (DED), which blocks death receptor pathway and inhibits apoptosis. METHODS: We collected normal cervical tissues from 28 subjects, CIN samples from 37 patients, and cervical cancer tissues from 40 patients. In these samples, we then measured the expression levels of IGFBP-5 and cFLIP via RT-PCR and immunohistochemistry, and we detected the presence of high-risk HPV by Hybrid capture II assays in cervical secretions provided by the subjects. RESULTS: significant differences in the expression of IGFBP-5 protein among the normal, CIN, and CC tissues (P < 0.05). The highest expression of IGFBP-5 protein was found in CIN stage II and III tissues, whereas the expression of IGFBP-5 in CC samples was decreased relative to controls. The expression level was affected by factors such as clinical stage, pathological differentiation, and lymph node metastasis. Relative to the controls, IGFBP-5 mRNA content was higher in the CC group and lower in the CIN group (P < 0.05). No expression of cFLIP protein or mRNA was detected in normal cervical tissues. However, the degree of pathological changes correlated with increasing expression of cFLIP protein and mRNA, and significant differences were therefore detected between groups (P < 0.05). The HPV infection rates in the CIN and CC groups were much higher than in the normal group (P < 0.05). CONCLUSION: IGFBP-5 expression is up-regulated in response to progression of CIN and down-regulated in invasive cervical carcinoma. Detection of IGFBP-5 and cFLIP expression levels, may prove particularly useful for diagnosing and differentiating CIN and CC.


Assuntos
Proteína Reguladora de Apoptosis Semelhante a CASP8 e FADD/genética , Proteína Reguladora de Apoptosis Semelhante a CASP8 e FADD/metabolismo , Proteína 5 de Ligação a Fator de Crescimento Semelhante à Insulina/genética , Proteína 5 de Ligação a Fator de Crescimento Semelhante à Insulina/metabolismo , Displasia do Colo do Útero/genética , Neoplasias do Colo do Útero/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Apoptose , Colo do Útero/metabolismo , Colo do Útero/virologia , Feminino , Humanos , Técnicas Imunoenzimáticas , Pessoa de Meia-Idade , Papillomaviridae/genética , Papillomaviridae/metabolismo , Infecções por Papillomavirus/genética , Infecções por Papillomavirus/patologia , Infecções por Papillomavirus/virologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Neoplasias do Colo do Útero/metabolismo , Neoplasias do Colo do Útero/virologia , Displasia do Colo do Útero/metabolismo , Displasia do Colo do Útero/virologia
6.
Zhonghua Fu Chan Ke Za Zhi ; 42(10): 683-7, 2007 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-18241544

RESUMO

OBJECTIVE: To evaluate efficacy and toxicity of topotecan and cisplatin (TP) as first line chemotherapy in epithelial ovarian cancer, and its effect on prognosis of the patients. METHODS: Totally 94 eligible patients with pathologically verified stage II - IV epithelial ovarian cancer were enrolled into 3 groups of this clinical trial. (1) TP group: 30 patients were treated with topotecan, 0.75 mg.m(-2).d(-1), for 5 days, and cisplatin, 75 mg/m(2), on day 1. (2) Paclitaxel and carboplatin (TC) group: 31 patients were treated with paclitaxel, 135 mg/m(2), on day 1, and carboplatin, given to an area under the curve (AUC) of 5, on day 1. (3) Cyclophosphamide and cisplatin (PC) group: 33 patients were treated with cyclophosphamide, 500 mg/m(2), on day 1, cisplatin 75 mg/m(2), on day 1. Cycles were repeated every 21 - 28 days. EFFICACY of the three combination regimens were evaluated after 6 - 8 courses. RESULTS: (1) EFFICACY: the overall response rate (ORR) in the TP group was 70%. Of the 30 patients, 8 achieved a complete response (CR) and 13 a partial response (PR). The ORR in the TC group was 77%. Of the 31 patients, 10 achieved a CR and 14 a PR. While the ORR in the PC group was 42%. Of the 33 patients, 5 achieved a CR and 9 a PR. There was no significant difference in clinical efficacy between TP group and TC group (P > 0.05). But there was a significant difference between TP group and PC group (P < 0.05). (2) Disease free survival (DFS): after median follow-up of 25 months, one-year disease free survival rate was 67% in TP group, 71% in TC group and 42% in PC group (P > 0.05). Two-year disease free survival rate was 57% in TP group, 64% in TC group and 39% in PC group (P > 0.05). (3) Overall survival (OS): One-year survival rate was 93% in TP group, 97% in TC group and 91% in PC group (P > 0.05). Two-year survival rate was 77% in TP group, 84% in TC group and 67% in PC group (P > 0.05). (4) TOXICITY: Grade III - IV myelosuppression was 60% (18/30) in TP group, 26% (8/31) in TC group and 30% (10/33) in PC group. The TP regimen had the greatest hematologic toxicity (P < 0.05). Nonhematologic toxicities were not significantly different among the three regimens (P > 0.05). CONCLUSIONS: As first line chemotherapy in epithelial ovarian cancer, TP regimen comparable to the standard chemotherapy regimen.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Cistadenocarcinoma Seroso/tratamento farmacológico , Neoplasias Ovarianas/tratamento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Carboplatina/administração & dosagem , Carboplatina/efeitos adversos , Cisplatino/administração & dosagem , Cisplatino/efeitos adversos , Ciclofosfamida/administração & dosagem , Ciclofosfamida/efeitos adversos , Cistadenocarcinoma Seroso/mortalidade , Cistadenocarcinoma Seroso/patologia , Intervalo Livre de Doença , Esquema de Medicação , Feminino , Febre/induzido quimicamente , Seguimentos , Humanos , Leucopenia/induzido quimicamente , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Neutropenia/induzido quimicamente , Neoplasias Ovarianas/mortalidade , Neoplasias Ovarianas/patologia , Paclitaxel/administração & dosagem , Paclitaxel/efeitos adversos , Prognóstico , Taxa de Sobrevida , Topotecan/administração & dosagem , Topotecan/efeitos adversos , Resultado do Tratamento
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