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1.
Plant Physiol Biochem ; 201: 107827, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37329689

RESUMO

Woody bamboos are important resource of industrial fibres. Auxin signaling plays a key role in multiple plant developmental processes, as yet the role of auxin/indole acetic acid (Aux/IAA) in culm development of woody bamboos has not been previously characterized. Dendrocalamus sinicus Chia et J. L. Sun is the largest woody bamboo documented in the world. Here, we identified two alleles of DsIAA21 gene (sIAA21 and bIAA21) from the straight- and bent-culm variants of D. sinicus, respectively, and studied how the domains I, i, and II of DsIAA21 affect the gene transcriptional repression. The results showed that bIAA21 expression was rapidly induced by exogenous auxin in D. sinicus. In transgenic tobacco, sIAA21 and bIAA21 mutated in domains i, and II significantly regulated plant architecture and root development. Stem cross sections revealed that parenchyma cells were smaller in transgenic plants than that in wild type plants. Domain i mutation changed the leucine and proline at position 45 to proline and leucine (siaa21L45P and biaa21P45L) strongly repressed cell expansion and root elongation by reducing the gravitropic response. Substitution of isoleucine with valine in domain II of the full length DsIAA21 resulted in dwarf stature in transgenic tobacco plants. Furthermore, the DsIAA21 interacted with auxin response factor 5 (ARF5) in transgenic tobacco plants, suggesting that DsIAA21 might inhibit stem and root elongation via interacting with ARF5. Taken together, our data indicated that DsIAA21 was a negative regulator of plant development and suggested that amino acid differences in domain i of sIAA21 versus bIAA21 affected their response to auxin, and might play a key role in the formation of the bent culm variant in D. sinicus. Our results not only shed a light on the morphogenetic mechanism in D. sinicus, but also provided new insights into versatile function of Aux/IAAs in plants.


Assuntos
Fator V , Nicotiana , Nicotiana/genética , Nicotiana/metabolismo , Fator V/genética , Fator V/metabolismo , Leucina/genética , Leucina/metabolismo , Ácidos Indolacéticos/metabolismo , Mutação/genética , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Regulação da Expressão Gênica de Plantas
2.
PeerJ ; 10: e13847, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35935247

RESUMO

Climate change will significantly affect the distribution area of species. Through establishing distribution model, we can simulate the current and future potential distribution range and provide reference for the introduction and cultivation planning of rare or economic plants. Dendrocalamus sinicus, endemic to Yunnan Province of China, is the strongest woody bamboo in the world. In the present study, the MaxEnt model was performed to simulate the distribution of different types of D. sinicus in China and neighboring countries or regions. The results suggested that the suitable distribution range of "straight type", the main type for cultivation and utilization, was 8°-30°N and 73°-122°E under the current climate conditions, while the potential distribution range of "bending type" was 6°-31°N and 79°-109°E. The two most key climate variables associated with distribution of "straight type" were "Temperature Annual Range" with 36.6% contribution rate and "Temperature Seasonality" (32.4%), while "Isothermality" (47.8%) and "Precipitation of Driest Month" (24.8%) for "bending type". Under different climate change scenarios (SSP1-2.6, SSP5-8.5) and periods (2050, 2090), the potential distribution area of the "straight type" were apparently different, indicating that the distribution area of D. sinicus will be affected significantly by climate changes in the future. Our findings would be not only beneficial to understanding limiting factors for natural distribution of D. sinicus, but also helpful for further germplasm conservation, introduction and cultivation planning of this rare woody bamboo.


Assuntos
Mudança Climática , Madeira , China , Temperatura , Previsões
3.
J Cancer ; 12(5): 1356-1364, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33531980

RESUMO

Purpose: To evaluate diagnostic and predictive values of the serum vascular endothelial growth factor-A (VEGF-A) level and systemic immune-inflammation index (SII) in small cell lung cancer (SCLC) patients. Methods: From January 2018 to April 2020, we prospectively enrolled 59 untreated SCLC patients in the study group and 50 non-neoplastic patients in the control group. Blood samples were collected at baseline, after the first two cycles of chemotherapy and at progression in the study group and at entry in the control group. Serum VEGF-A was measured by chemiluminescence, SII was calculated based on complete blood count results, and the relationship between the VEGF-A/SII and clinicopathological characteristics, chemotherapeutic efficacy and progression-free survival (PFS) of SCLC patients was analyzed. Results: Baseline serum VEGF-A was significantly higher in SCLC patients than in non-neoplastic patients (P<0.001), while baseline SII was not (P=0.114). There was no correlation between baseline VEGF-A and SII in SCLC patients (P=0.123); however, there was a significant correlation between baseline VEGF-A and disease stage and central nervous system (CNS) metastasis (P=0.021 and P=0.012, respectively), as well as between baseline SII and disease stage and liver metastasis (P=0.026 and P=0.018, respectively). Serum VEGF-A was significantly lower than the pretreatment level after 2 cycles of treatment (P=0.049) but was not different at progression (P=0.247). Baseline VEGF-A was correlated with the treatment response of first-line chemotherapy (P=0.001), while baseline SII was not (P=0.392). Kaplan-Meier survival analysis suggested that the PFS of first-line chemotherapy was significantly longer in the low-VEGF-A group at baseline than the high-VEGF-A group (11.37 vs. 6.17 months, P<0.001). There was a trend toward longer PFS of first-line chemotherapy in the low-SII group at baseline than the high-SII group, but the difference was not significant (12.10 vs. 9.10 months, P>0.050). Univariate and multivariate Cox regression analyses suggested that baseline VEGF-A (HR: 3.443, 95% CI: 1.330-8.908, P=0.011) was an independent prognostic factor for PFS in SCLC patients. Conclusions: Baseline serum VEGF-A and SII are associated with important clinicopathological characteristics of SCLC patients. VEGF-A, but not SII, has the ability of diagnosis and predicting first-line chemotherapeutic efficacy and prognosis in SCLC patients.

4.
Ann Rheum Dis ; 79(11): 1460-1467, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32737104

RESUMO

OBJECTIVES AND METHODS: With 432 513 samples from UK Biobank dataset, multivariable linear/logistic regression were used to estimate the relationship between psoriasis/psoriatic arthritis (PsA) and estimated bone mineral density (eBMD)/osteoporosis, controlling for potential confounders. Here, confounders were set in three ways: model0 (including age, height, weight, smoking and drinking), model1 (model0 +regular physical activity) and model2 (model1 +medication treatments). The eBMD was derived from heel ultrasound measurement. And 4904 patients with psoriasis and 847 patients with PsA were included in final analysis. Mendelian randomisation (MR) approach was used to evaluate the causal effect between them. RESULTS: Lower eBMD were observed in patients with PsA than in controls in both model0 (ß-coefficient=-0.014, p=0.0006) and model1 (ß-coefficient=-0.013, p=0.002); however, the association disappeared when conditioning on treatment with methotrexate or ciclosporin (model2) (ß-coefficient=-0.005, p=0.28), mediation analysis showed that 63% of the intermediary effect on eBMD was mediated by medication treatment (p<2E-16). Patients with psoriasis without arthritis showed no difference of eBMD compared with controls. Similarly, the significance of higher risk of osteopenia in patients with PsA (OR=1.27, p=0.002 in model0) could be eliminated by conditioning on medication treatment (p=0.244 in model2). Psoriasis without arthritis was not related to osteopenia and osteoporosis. The weighted Genetic Risk Score analysis found that genetically determined psoriasis/PsA were not associated with eBMD (p=0.24 and p=0.88). Finally, MR analysis showed that psoriasis/PsA had no causal effect on eBMD, osteoporosis and fracture. CONCLUSIONS: The effect of PsA on osteoporosis was secondary (eg, medication) but not causal. Under this hypothesis, psoriasis without arthritis was not a risk factor for osteoporosis.


Assuntos
Antirreumáticos/uso terapêutico , Densidade Óssea/efeitos dos fármacos , Osteoporose/epidemiologia , Psoríase/complicações , Psoríase/tratamento farmacológico , Humanos , Análise da Randomização Mendeliana
5.
BMC Plant Biol ; 19(1): 418, 2019 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-31604418

RESUMO

BACKGROUND: So far, little is known in detail about mating systems of woody bamboos. Paternity analysis of offspring improved our understanding of these systems, and contributed to their germplasm conservation and genetic improvement. RESULTS: In this study, a paternity analysis of offspring from two consecutive mass or sporadically flowering events of Dendrocalamus membranaceus and D. sinicus were conducted to determine their mating system and pollen dispersal using the program COLONY based on simple sequence repeat (SSR) markers. Two sporadically flowering populations of D. sinicus (C1, C2) obtained relatively high paternity assignments rates (69.0-71.4%). Meanwhile, among three populations of D. membranaceus, the sporadically flowering population A also had much higher paternity assignments rates (56.4%) than mass flowering populations B1(28.6%) and B2 (42.5%). Both D. membranaceus and D. sinicus had mixed mating systems while their mating patterns were variable depending on pollination conditions. The maximum pollen dispersal distances were 90 m and 4378 m for D. membranaceus and D. sinicus populations, respectively, and the mating distances of these two species focused on ranges of ca. 0-50 m and 0-1500 m, respectively. CONCLUSIONS: These results revealed for the first time variable mating patterns in woody bamboos. This suggests half-sib seeds from the same bamboo clump may have different male parents and it is crucial to clarify genetic origin in woody bamboos' breeding programs. The results also indicate the importance of pollinators in the mating systems of tropical woody bamboos.


Assuntos
Poaceae/fisiologia , Polinização , Marcadores Genéticos , Repetições de Microssatélites , Poaceae/genética , Reprodução/genética , Especificidade da Espécie
6.
Sci Rep ; 8(1): 16933, 2018 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-30446690

RESUMO

Evolutionary processes, speciation in woody bamboos are presently little understood. Here we used Dendrocalamus sinicus Chia & J.L. Sun as a model species to investigate dispersal or vicariance speciation in woody bamboos. Variation in three chloroplast DNA (cpDNA) fragments and eight simple sequence repeat markers (SSR) among 232 individuals sampled from 18 populations across the known geographic range of D. sinicus was surveyed. D. sinicus populations exhibited a high level of genetic differentiation which divided them into two groups that are consistent with different culm types. Eleven haplotypes and two lineages (Straight-culm and Sinuous-culm lineages) were identified from phylogenetic analyses, and a strong phylogeographic structure across the distribution range was found. The demographic and spatial expansion times of the Straight-culm lineage were calculated as 11.3 Kya and 20.8 Kya, respectively. The populations of D. sinicus had experienced dispersal and long-term isolation, although this trace was diluted by contemporary gene flow revealed by SSR data. Our results provide an phylogeographic insight to better understand the speciation processes of woody bamboos.


Assuntos
Evolução Molecular , Variação Genética , Genética Populacional , Poaceae/genética , DNA de Cloroplastos/genética , Haplótipos , Repetições de Microssatélites , Filogenia , Polimorfismo Genético
7.
AoB Plants ; 9(3): plx021, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28685014

RESUMO

An understanding of the breeding systems and pollination of agriculturally important plants is critical to germplasm improvement. Breeding system characteristics greatly influence the amount and spatial distribution of genetic variation within and amongst populations and influence the rarity and extinction vulnerability of plant species. Many woody bamboos have a long vegetative period (20-150 years) followed by gregarious monocarpy. Relatively, little is known about their pollination and breeding systems. We studied these characteristics in wild Dendrocalamus membranaceus populations and cultivated Dendrocalamus sinicus populations distributed in the Yunnan Province of China. Floral morphology, flower visitors and breeding system were studied from 2013 to 2015. Both bamboos were protogynous, but flowering periods of florets overlapped providing opportunities for self-pollination amongst florets, especially in D. membranaceus. There was no agamospermy in either species. Seed set of D. sinicus was low (0.42 ± 0.42 %) under natural pollination but higher (8.89 ± 2.55 %) after artificial xenogamy. Seed set of D. membranaceus was higher (7.49 ± 0.82 %) in mass flowering populations and 2.14 ± 0.25 % in sporadically flowering populations. The Asian honeybee Apis cerana could provide cross-pollination of D. membranaceus and D. sinicus, and flower visitation peaked at 1000-1200 h. Pollination limitation due to lack of pollinators or pollen was detected in the cultivated populations of D. sinicus and sporadically flowering populations of D. membranaceus. Pollination limitation was not obvious within mass flowering populations. Hand pollination could significantly increase seed set of these two bamboo species. Dendrocalamus membranaceus and D. sinicus were self-compatible and have a mixed-mating system with outcrossing being pre-dominant. Their seed production was limited by the quantity of pollen and pollinator activity. Honeybees were observed as effective pollinators.

8.
PLoS One ; 11(4): e0153845, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27077651

RESUMO

The flowering periods of woody bamboos, seed set, natural regeneration and death after flowering have been rarely observed and evaluated in the field. Dendrocalamus membranaceus Munro, a tropical woody bamboo mainly distributed in the Yunnan, displayed both sporadic as well as gregarious (mass) flowering and fruited from 2006 to 2013 following severe droughts. The aim of this study is to examine potential differences in seed set and natural regeneration between the two flowering patterns in natural D. membranaceus forests. We investigated and analyzed seed set, seed germination, seedling growth and mortality in both mass and sporadic flowering populations. Observations were made over a period of three years to record changes in bamboo seedling density, height and culm diameter. We observed a low natural seed set ranging from 1.76% to 7.49%, and a relatively high seed germination rate in the nursery from 59.6% to 71.0% for both types of flowering populations. Seeds germinated in 5-7 days after sowing and the germination period lasted 10-15 days. Seed set and germination rates in mass-flowering populations were significantly higher than those of sporadically flowering stands. The seedlings within sporadically flowering populations died within two years. In comparison, seedling mortality in the mass flowering population increased over two periods of observation from 64.92% to 98.89%, yet there was good seedling establishment left over, which showed mean height and mean culm diameter increasing by 1053.25% and 410.71%, respectively, in the second year of observations, and 137.10%, and 217.48%, respectively, in the third year. There are significant differences in seed set, natural regeneration ability and sustainability of bamboo populations between the mass flowering and sporadically flowering populations of D. membranaceus. Sporadic flowering populations failed to produce effective regeneration, while mass flowering populations were able to regenerate successfully. This study provides useful insights for conservation and natural forest management of D. membranaceus. We consider the merits of introducing other genetic provenances towards long-term maintenance of the stand features at sporadically flowering sites; meanwhile, the most economic option for mass flowering stands is to allow natural regeneration to take place through protecting such sites from further disturbance.


Assuntos
Bambusa/fisiologia , Flores/fisiologia , Regeneração , Plântula/fisiologia , Sementes/fisiologia , Bambusa/crescimento & desenvolvimento , China , Conservação dos Recursos Naturais , Flores/crescimento & desenvolvimento , Florestas , Geografia , Germinação , Plântula/crescimento & desenvolvimento , Sementes/crescimento & desenvolvimento , Fatores de Tempo
9.
Zhen Ci Yan Jiu ; 38(2): 134-9, 2013 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-23819216

RESUMO

OBJECTIVE: To observe the effect of different moxibustion intervention on expression of interleukin-1 (IL-l) and tumor necrosis factor-alpha (TNF-alpha) in the synovial fluid of hind-knee joint in rheumatoid arthritis (RA) rabbits. METHODS: Forty Japanese big-ear white rabbits (half male and half female) were randomized into normal control, RA model, direct-moxibustion, ginger-partitioned moxibustion and warm moxibustion groups (n= 8). RA model was established by injection of Freund's Complete Adjuvant (0. 5 mL/kg) into the articular cavities of the rabbits' bilateral hind-limbs. Moxibustion intervention was applied to unilateral "Shenshu" (BL 23) and "Zusanli"(ST 36) regions alternatively for 20 min from the 7th day on after modeling, once daily for 3 weeks except Sundays. The circumference of the hindlimb-knee joint was measured using a tape measure and the contents of IL-1 and TNF-alpha in the synovial fluid of articular cavities were detected by ELISA. RESULTS: In comparison with the normal control group, the circumference values of the bilateral hind-knee joints, and the contents of IL-1 and TNF-alpha in the synovial fluid of articular cavities in the model group were significantly increased (P<0. 01). After the moxibustion treatment, compared with the model group, the circumference values of the bilateral hind-knee joints, and IL-1 and TNF-alpha contents of the synovial fluid in the warm moxibustion, direct moxibustion and ginger-partitioned moxibustion groups were remarkably reduced (P<0.01, P<0.05). The effects of the ginger-partitioned group were significantly superior to those of both warm moxibustion and direct moxibustion groups in decreasing the swelled hind-knee joint circumference on day 21 after the treatment and down-regulating synovial fluid inflammatory cytokines IL-1 and TNF-alpha levels (P<0. 05). CONCLUSION: Warm, direct and ginger-separated moxibustion interventions all can reduce inflammatory reactions of the knee-joint and suppress inflammatory cytokine IL-1 and TNF-alpha levels of the synovial fluid in RA rabbits, which may contribute to its effect in improving RA in clinic. The therapeutic effect of ginger-partitioned muxibustion intervention is apparently better.


Assuntos
Artrite Reumatoide/genética , Artrite Reumatoide/terapia , Interleucina-1/genética , Moxibustão/métodos , Fator de Necrose Tumoral alfa/genética , Pontos de Acupuntura , Animais , Artrite Reumatoide/imunologia , Feminino , Humanos , Interleucina-1/imunologia , Masculino , Coelhos , Fator de Necrose Tumoral alfa/imunologia
10.
Zhongguo Zhen Jiu ; 33(3): 241-6, 2013 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-23713311

RESUMO

OBJECTIVE: To observe the specificity relationship between acupuncture at "Hegu" (LI 4) and the facial muscular movement in rhesus monkeys under the physiological state by using neuromuscular electrical measurement technique. METHODS: Eighteen rhesus monkeys were randomized into a Hegu group, a Houxi group and a Waiguan group, 6 monkeys in each one. Under the physiological state, EMG was detected on the frontal muscle, zygomatic muscle and orbicular muscle before and after acupuncture at different acupoints. The impacts of acupuncture on the facial EMG were studied and compared among different acupoints. RESULTS: With acupuncture at "Hegu" (LI 4), the latency was reduced (P < 0.01) and the peak value and area were increased (P < 0.05, P < 0.01) in the frontal EMG; the area and the peak value were increased (P < 0.01, P < 0.05) and latency was reduced (P < 0.05) in the zygomatic EMG; the frequency was increased (P < 0.01) and the latency was reduced (P < 0.05) in the orbicular EMG. Before and after acupuncture at "Hegu" (LI 4), the change rates of EMG frequency, peak value, area and latency on the frontal, zygomatic and orbicular muscles were higher than those at "Houxi" (SI 3) and "Waiguan" (TE 5) (P < 0.05, P < 0.01) separately. CONCLUSION: The relative specificity presents between Hegu (LI 4) and facial muscular movement.


Assuntos
Pontos de Acupuntura , Terapia por Acupuntura , Face/fisiologia , Animais , Eletromiografia , Feminino , Humanos , Macaca mulatta , Masculino , Modelos Animais
11.
Am J Bot ; 99(9): e347-9, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22933358

RESUMO

PREMISE OF THE STUDY: Microsatellite primers were developed in the strongest and most economically important bamboo species, Dendrocalamus sinicus, to investigate its genetic variability. METHODS AND RESULTS: Using the Fast Isolation by AFLP of Sequences COntaining Repeats (FIASCO) protocol, 16 polymorphic primer sets were identified within 24 individuals from two geographic locations. The number of alleles per locus ranged from two to four, with a mean of 2.6. The observed and expected heterozygosities varied from 0 to 1.000 and from 0.311 to 0.754, respectively. The cross-amplification of the 16 primer pairs was tested in four other Dendrocalamus species, and nine to 13 (56.3-81.3%) primer pairs were successfully amplified. CONCLUSIONS: These markers will be useful for studies on the genetic diversity of D. sinicus, which may facilitate conservation of this species.


Assuntos
Bambusa/genética , Repetições de Microssatélites/genética , Madeira/genética , China , Primers do DNA/metabolismo , Dados de Sequência Molecular , Polimorfismo Genético , Especificidade da Espécie
12.
Int J Mol Sci ; 13(4): 4446-4457, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22605989

RESUMO

Dendrocalamus membranaceus Munro is a woody bamboo with a high economic and ecological value that often occurs as natural stands, such as in the large-scale forested areas of China's Yunnan Province. Due to its overexploitation, the habitat of D. membranaceus in Yunnan has been dramatically reduced, and the quality of the stands has declined. As a preliminary analysis in considering the effective protection for these germplasm resources, we assessed the genetic diversity of 12 natural populations in Yunnan, using inter-simple sequence repeat (ISSR) markers. From 10 ISSR primers, we generated 155 bands, of which 153 were polymorphic (98.71%). Compared with other species in the genus, this species demonstrated a greater genetic diversity (S = 0.349) and lower genetic differentiation (G(ST) = 0.252). Our analysis of molecular variance revealed that the genetic differentiation among the populations is significant. A large proportion of the genetic variation (78.95%) resides among the individuals within populations, whereas only 21.05% are found among populations. Mantel tests indicated no significant correlation between genetic and geographic distances among the populations. Given the low sexual reproducibility and characteristics of monocarpic plants, we recommend implementing in situ conservation measures for all of the D. membranaceus populations in Yunnan and collecting sufficient samples for ex situ conservation. Furthermore, the conservation area should be extended to its main natural habitats, the Lancang-Mekong River Valley.


Assuntos
DNA de Plantas/genética , Repetições de Microssatélites/genética , Sasa/genética , China , Conservação dos Recursos Naturais , DNA de Plantas/análise , Ecossistema , Genética Populacional , Geografia , Filogenia , Polimorfismo Genético
13.
Mol Phylogenet Evol ; 48(3): 809-24, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18593600

RESUMO

This study presented the first molecular phylogenetic analysis of the major clades of woody bamboos of the Old World tropics based on nuclear and chloroplast sequences (ITS, GBSSI and trnL-F). Sequence data from 53 species, representing 17 paleotropical woody bamboo genera, were analyzed using the maximum parsimony and Bayesian inference methods. All examined ingroup taxa were clustered into two clades, i.e., the Bambusinae+Dinochloa clade and the Melocanninae clade. The former clade included Bambusa, Bonia, Dendrocalamus, Dendrocalamopsis, Dinochloa, Gigantochloa, Molecalamus, Neomicrocalamus, Neosinocalamus, Oxytenanthera s. str. (sensu stricto), Racemobambos and Thyrsostachys. The Melocanninae clade consisted of Cephalostachyum, Leptocanna (better treated as part of Cephalostachyum), Melocanna, Pseudostachyum and Schizostachyum s. str. The subtribe Racemobambosinae and tribes Dendrocalameae and Oxytenanthereae were not supported and may be better placed in subtribe Bambusinae. The ovary characters seemed to be good criteria to distinguish these two clades. The reconstruction of ancestral fruit characters indicated that the bacoid caryopsis, namely, fleshy or berry-like fruits, was found to be scattered in three lineages of the examined paleotropical woody bamboos. Fruit characters are thus not reliable indicators of phylogeny and bacoid caryopsis likely represents a specialization for particular ecological conditions.


Assuntos
Bambusa/genética , Plastídeos/genética , Sintase do Amido/genética , Teorema de Bayes , Análise por Conglomerados , Primers do DNA/química , DNA Intergênico , Ecologia , Evolução Molecular , Genes de Plantas , Filogenia , Análise de Sequência de DNA
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