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1.
Front Cell Infect Microbiol ; 14: 1373036, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38873095

RESUMO

Serratia marcescens, as a Gram-negative opportunistic pathogen, is a rare cause of peritonitis and has worse clinical outcomes than Gram-positive peritonitis. In this case report, we describe a case of Serratia marcescens associated peritonitis that was successfully cured without catheter removal. A 40-year-old male patient with peritoneal dialysis who worked in the catering industry was admitted to the hospital for 16 hours after the discovery of cloudy peritoneal dialysate and abdominal pain. Ceftazidime and cefazolin sodium were immediately given intravenously as an empirical antibiotic regimen. After detecting Serratia marcescens in the peritoneal diasate culture, the treatment was switched to ceftazidime and levofloxacin. The routine examination of peritoneal dialysate showed a significant decrease in white blood cells, the peritoneal dialysate became clear, and the peritoneal dialysis catheter was retained. The patient was treated for 2 weeks and treated with oral antibiotics for 1 week. It is necessary to further strengthen the hygiene of work environment to prevent Serratia marcescens infection in peritoneal dialysis patients. We recommend that patients with Serratia marcescens associated peritonitis should be treated with a combination of antibiotics as early as possible empirically, and at the same time, the peritoneal dialysis fluid culture should be improved, and the antibiotic regimen should be timely adjusted according to the drug sensitivity results. For patients with clinical symptoms for more than 3 days, considering the strong virulence of Serratia marcescens, whether to use meropenem directly or not can provide a reference for clinical decision-making. Further clinical studies are needed to achieve more precise anti-infective treatment.


Assuntos
Antibacterianos , Diálise Peritoneal , Peritonite , Infecções por Serratia , Serratia marcescens , Humanos , Serratia marcescens/isolamento & purificação , Masculino , Peritonite/microbiologia , Peritonite/tratamento farmacológico , Adulto , Infecções por Serratia/microbiologia , Antibacterianos/uso terapêutico , Antibacterianos/administração & dosagem , Diálise Peritoneal/efeitos adversos , Resultado do Tratamento , Remoção de Dispositivo , Levofloxacino/uso terapêutico , Ceftazidima/uso terapêutico , Ceftazidima/administração & dosagem , Cefazolina/uso terapêutico
2.
Plants (Basel) ; 12(18)2023 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-37765433

RESUMO

Understanding the water status of specific organs can be helpful in evaluating the life activities and growth conditions of maize. To accurately judge organ growth conditions and thus design appropriate interventions, it is necessary to clarify the true water dynamics of each maize organ. Using multiple maize cultivars with different growth periods, spatio-temporal water dynamics were analyzed here in the leaves, stalks, and ear components. Leaf water content was found to gradually decrease from both the bottom and top of the plant to the middle, whereas stalk water content decreased sequentially from the top to the bottom. Each successively higher node from the bottom of the plant was associated with decreases of 0.99% and 1.27% water content in the leaves and stalks, respectively. The water dynamics in leaves and internodes showed three clear stages: the slow loss, rapid loss, and balance stage. A water content of 60% appeared to be an irreversible turning point for initiation of senescence. Using normalized growth period as a measure, each of the tested cultivars could be assigned into one of two types based on their water dynamics: stay-water or general type. General-type cultivars had a shorter duration with a high water content and a water loss rate approximately twice as high as that of the stay-water type. This may have been related to the leaf senescence characteristics. However, the stay-water trait did not interfere with water dynamics of the ear components. Therefore, it may not be robust to evaluate the kernel dehydration of maize according to leaf senescence conditions due to the weak correlation between kernel water content and leaf senescence characteristics.

3.
Front Neurol ; 14: 1201964, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37492853

RESUMO

A Solitary Fibrous Tumor (SFT) is a rare, aggressive, and metastasis- and recurrence- prone mesenchymal tumor. In this case report and review, we describe a rare instance of intracranial SFT, discovered for the first time. It was discovered in 2008 and following total surgical removal, the pathology was categorized as hemangiopericytoma cell tumor (HPC) at the time by WHO tumor criteria. An imaging review 8 months after surgery revealed a tumor recurrence: combined radiation and gamma-knife therapy was continued throughout this time. The tumor did not metastasis until June 2018 when it presented in the pancreas with ruptured bleeding and a postoperative pathology was suggestive of SFT. Fortunately, the patient is still alive nearly 3 years after the 2020 surgery, after staged surgical resection and combined multimedia therapy, with no imaging or clinical evidence of a recurrent intracranial primary lesions. To our knowledge, there is no previous record of using a combined treatment modality for Intracranial Solitary Fibrous Tumor (ISFT). Combined with an account of the patient's experience, we empirically describe a combined approach with a preference for gross-total resection (GTR), supplemented by multimodal assistance with stereotactic (radiotherapy), gamma knife (GK), molecular targeting, and immunization for patients admitted acutely, with accurate preoperative identification and aggressive management after intraoperative case response to maximize treatment of recurrent ISFT and improve prognosis. We recommend multimodal management for SFT with prolonged-term recurrence and metastases, both for the control benefits of GTR, RT, or GK for local recurrence and for the positive prognosis of targeted and immune metastases.

4.
Sci Total Environ ; 883: 163507, 2023 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-37059139

RESUMO

Increasing crop yields to ensure food security while also reducing agriculture's environmental impacts to ensure green sustainable development are great challenges for global agriculture. Plastic film, widely used to improve crop yield, also creates plastic film residue pollution and greenhouse gas emissions that restricts the development of sustainable agriculture. So, one of those challenges is to reduce plastic film use while also ensuring food security, and thus promote green and sustainable development. A field experiment was conducted during 2017-2020 at 3 farmland areas, each with different altitudes and climate conditions, in northern Xinjiang, China. We investigated the effects on maize yield, economic returns, and greenhouse gas (GHG) emissions of plastic film mulching (PFM) versus no mulching (NM) methods in drip-irrigated maize production. We also chose maize hybrids with 3 different maturation times and used 2 planting densities to further investigate how those differences more specifically affect maize yield, economic returns, and greenhouse gas (GHG) emissions under each mulching method. We found that by using maize varieties with a utilization rate of accumulated temperature (URAT) <86.6 % with NM, and increasing the planting density by 3 plants m-2, yields and economic returns improved and GHG emissions reduced by 33.1 %, compared to those of PFM maize. The maize varieties with URATs between 88.2 % to 89.2 %, had the lowest GHG emissions. We discovered that by matching the required accumulated temperatures of various maize varieties to environmental accumulated temperatures, along with filmless and higher density planting, and modern irrigation and fertilization practices, yields increased and residual plastic film pollution and carbon emissions reduced. Therefore, these advances in agronomic management are important steps toward reducing pollution and achieving carbon peak and carbon neutrality goals.


Assuntos
Gases de Efeito Estufa , Zea mays , Carbono , Solo/química , Gases de Efeito Estufa/análise , Plásticos , Agricultura/métodos , Segurança Alimentar , China , Fertilizantes
5.
J Sci Food Agric ; 103(10): 5061-5069, 2023 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-36990972

RESUMO

BACKGROUND: Global warming has led to methods of planting late-maturing maize varieties in northeast China that have hindered the development of physiological maturity (PM) at harvest and the use of mechanical grain harvesting (MGH). Under these conditions it is difficult to balance the drying characteristics of maize varieties and to make full use of accumulated temperature resources in such a way as to reduce grain moisture content (GMC) at harvest. RESULTS: The effective accumulated temperature (AcT) and the drying rates of different varieties vary. In northeast China, with a GMC of 25%, the growth periods of a fast-drying variety (FDV) and a slow-drying variety (SDV) were 114-192 days and 110-188 days respectively. After PM, the FDV needed 47 days and the SDV needed 51 days to reduce the GMC to be ready for MGH. Harvested with a GMC of 20%, the growth period for the FDV was 97-175 days and for the SDV it was 90-171 days. After PM, the FDV required 64 days and the SDV needed 70 days to reduce the GMC to be ready for MGH. CONCLUSION: Matching cultivars with AcT can help farmers to choose suitable varieties. Promoting MGH may boost maize production, thus ensuring China's food security. © 2023 Society of Chemical Industry.


Assuntos
Grão Comestível , Zea mays , Temperatura , Grão Comestível/química , Aquecimento Global , China
6.
Front Plant Sci ; 14: 1006245, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36844043

RESUMO

Quantifying the effects of various environmental conditions on maize leaf number is essential to understanding the environmental adaptations and population structure of maize plants and for enhancing maize productivity. In this study, seeds of three temperate-adapted maize cultivars, each belonging to different maturity classes, were sown on eight different dates. Sowing dates ranged from the middle of April to early July, which allowed us to cover a wide range of environmental conditions. Random forest regression and multiple regression models with variance partitioning analyses were used to assess the effects of environmental factors on the number of leaves and their distributions on maize primary stems. We demonstrated that the total leaf number (TLN) increased in the three cultivars in the following order: FK139 < JNK728 < ZD958, and variations in TLN for each cultivar were 1.5, 1.76, and 2.75 leaves, respectively. The variation in TLN was ascribed to changes in LB (leaf number below the primary ear), which were higher than variations in LA (leaf number above the primary ear). Variations in TLN and LB were mainly affected by the photoperiod during growth stages V7 to V11, and differences in TLN and LB in response to different photoperiods ranged from 1.34 to 2.95 leaves h-l. Variations in LA was mainly affected by temperature-related factors. Therefore, the results of this study enhanced our current understanding of key environmental conditions that affect maize leaf numbers, and provides scientific support for the benefits of adjusting sowing dates and selecting suitable cultivars to mitigate the effects of climate change on maize production.

7.
Plant Physiol Biochem ; 196: 454-462, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36758292

RESUMO

Phyllochron, the reciprocal of the leaf appearance rate, is a critical genetic parameter in crop models for predicting growth characteristics and yield. Previous studies have shown that existing observations and predictive algorithms do not adequately represent a broad range of cultivars and environments. Here, we conducted a series of experiments in the field to quantify and disentangle the effects of sowing date and cultivar on maize leaf collar appearance (LCA). A bilinear model was found to accurately fit maize LCA (R2adj > 0.99); this model revealed a slower rate of LCA for the first leaves compared to the last leaves. Turning points in the model occurred between the 9.2th and the 13.1th leaf, nearly always below the ear leaf and around a leaf age index (LAI) of 60.0%. The phyllochron before the turning point (PHYLL Ⅰ) was significantly higher than the phyllochron after the turning point (PHYLL Ⅱ) for all three maize cultivars, and PHYLL Ⅰ was approximately two times higher than PHYLL Ⅱ on average. Both PHYLL Ⅰ and PHYLL Ⅱ were significantly affected by sowing date and cultivar. Variations in PHYLL Ⅰ and PHYLL Ⅱ indicated strong plasticity in maize phyllochron at different leaf ranks. The results of this study are critical for improvement of maize management practices and extend the applicability of phyllochron-collar measurements in crop models.


Assuntos
Folhas de Planta , Zea mays , Zea mays/genética , Algoritmos
8.
AoB Plants ; 14(6): plac053, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36545299

RESUMO

Nitrogen (N) utilization for crop production under N deficiency conditions is subject to a trade-off between maintaining specific leaf N content (SLN) important for radiation-use efficiency versus maintaining leaf area (LA) development, important for light capture. This paper aims to explore how maize deals with this trade-off through responses in SLN, LA and their underlying traits during the vegetative and reproductive growth stages. In a 10-year N fertilization trial in Jilin province, Northeast China, three N fertilizer levels have been maintained: N deficiency (N0), low N supply (N1) and high N supply (N2). We analysed data from years 8 and 10 of this experiment for two common hybrids. Under N deficiency, maize plants maintained LA and decreased SLN during vegetative stages, while both LA and SLN decreased comparably during reproductive stages. Canopy SLA (specific leaf area, cm2 g-1) decreased sharply during vegetative stages and slightly during reproductive stages, mainly because senesced leaves in the lower canopy had a higher SLA. In the vegetative stage, maize maintained LA at low N by maintaining leaf biomass (albeit hence having N content/mass) and slightly increasing SLA. These responses to N deficiency were stronger in maize hybrid XY335 than in ZD958. We conclude that the main strategy of maize to cope with low N is to maintain LA, mainly by increasing SLA throughout the plant but only during the vegetative growth phase.

9.
Plants (Basel) ; 11(20)2022 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-36297747

RESUMO

While plastic film mulching and proper high-density planting are important methods that can improve maize yield, years of accumulated residual film have created soil pollution and degraded soil, and thus has impeded sustainable agriculture development. Here, we compared the stalk and root lodging resistances of three maize cultivars grown at two planting densities both with (FM) and without (NM) plastic film mulch. Our aim was to provide a theoretical basis that may help assure a future of successful no-film planting with increased planting density. The results showed that, compared with FM, the average dry weight per unit length and bending strength of basal internode decreased for all cultivars at both planting densities in the NM treatment. At 9.0 × 104 plants ha-1, the stalk breaking force (SFC) of Xinyu77, KWS9384, and KWS2030 in the NM treatment decreased by 4%, 21%, and 22%, respectively. At 12.0 × 104 plants ha-1, SFC of Xinyu77 and KWS2030 increased by 14% and 1%, respectively, while KWS9384 decreased by 10%. Additionally, the root diameter, length, volume, width, depth, and the vertical root-pulling force of maize decreased. Although the lodging resistance of maize grown without film mulch was lower than that of maize grown with it, those adverse effects can be mitigated by selecting suitable cultivars and by using proper high-density planting and appropriate cultivation measures.

10.
Front Plant Sci ; 13: 906060, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35755643

RESUMO

A quantitative understanding of the factors driving changes in grain filling is essential for effective prioritization of increasing maize yield. Grain filling is a significant stage in maize yield formation. Solar radiation is the energy source for grain filling, which is the ultimate driving factor for final grain weight and grain filling capacity that determine maize yield. Here, we first confirmed the quantitative relationships between grain filling parameters and photosynthetically active radiation (PAR) by conducting field experiments using different shading and plant density conditions and cultivars in 2019 and 2020 in Xinjiang, China. The results showed that with every 100 MJ m-2 increase in PAR, the average grain filling rate (G ave), maximum grain-filling rate (G max), and the kernel weight at the time of maximum grain-filling rate (W max) increased by 0.073 mg kernel-1 day-1, 0.23 mg kernel-1 day-1, and 0.24 mg kernel-1, and the time of maximum grain-filling rate (T max) delayed by 0.91 day. Relative changes in PAR were significantly and positively correlated with relative changes in yield and G ave. With every 1% change in PAR, yield and G ave changed by 1.16 and 0.17%, respectively. From the perspective of grain filling capacity, DH618 was a more shade-resistant cultivar than XY335 and ZD958. It is urgent to breed maize cultivars with low light tolerance and high grain yield in the face of climate change, particularly the decrease in solar radiation.

11.
Front Plant Sci ; 12: 727134, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34603357

RESUMO

Solar radiation is the energy source for crop growth, as well as for the processes of accumulation, distribution, and transfer of photosynthetic products that determine maize yield. Therefore, learning the effects of different solar radiation amounts on maize growth is especially important. The present study focused on the quantitative relationships between solar radiation amounts and dry matter accumulations and transfers in maize. Over two continuous years (2017 and 2018) of field experiments, maize hybrids XY335 and ZD958 were grown at densities of 4.5 × 104 (D1), 7.5 × 104 (D2), 9 × 104 (D3), 10.5 × 104 (D4), and 12 × 104 (D5) plants/ha at Qitai Farm (89°34'E, 44°12'N), Xinjiang, China. Shading levels were 15% (S1), 30% (S2), and 50% (S3) of natural light and no shading (CK). The results showed that the yields of the commonly planted cultivars XY335 and ZD958 at S1, S2, and S3 (increasing shade treatments) were 7.3, 21.2, and 57.6% and 11.7, 31.0, and 61.8% lower than the control yields, respectively. Also, vegetative organ dry matter translocation (DMT) and its contribution to grain increased as shading levels increased under different densities. The dry matter assimilation amount after silking (AADMAS) increased as solar radiation and planting density increased. When solar radiation was <580.9 and 663.6 MJ/m2, for XY335 and ZD958, respectively, the increase in the AADMAS was primarily related to solar radiation amounts; and when solar radiation was higher than those amounts for those hybrids, an increase in the AADMAS was primarily related to planting density. Photosynthate accumulation is a key determinant of maize yield, and the contributions of the vegetative organs to the grain did not compensate for the reduced yield caused by insufficient light. Between the two cultivars, XY335 showed a better resistance to weak light than ZD958 did. To help guarantee a high maize yield under weak light conditions, it is imperative to select cultivars that have great stay-green and photosynthetic efficiency characteristics.

12.
Plant Methods ; 16(1): 148, 2020 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-33292355

RESUMO

BACKGROUND: The accurate evaluation of the stalk-lodging resistance during the late stage of maize growth can provide a basis for the selection of cultivars, the evaluation of cultivation techniques, and timely mechanical grain harvesting. In this study, the critical wind speed of stalk breaking, plant morphology, stalk mechanical strength, and lodging rate were investigated in 10 maize cultivars to identify the parameters evaluate lodging resistance during the later growth stage of maize. Clarify the relationship with the stalk mechanical strength, critical wind speed of stalk breaking, and natural lodging rate in the field. RESULTS: The results showed that, in the late growth stage, with increasing number of days after physiological maturity, (1) the stalk lodging rate gradually increased, (2) the stalk breaking force and rind penetration strength (RPS) of the third internode above the soil gradually decreased, and (3) the critical wind speed of stalk breaking increased first and then decreased, and was highest at about 16-24 days after physiological maturity. The position of stalk lodging mostly occurred between second and fifth internodes. The torque at the base of maize plant increased as wind speed increased, and the different of torque was excited among different maize cultivars under same wind speed. Furthermore, the stalk lodging rate was significantly negatively correlated with the critical wind speed of stalk breaking. Additionally, the critical wind speed of stalk breaking was significantly positively correlated with the stalk breaking force and the RPS. CONCLUSION: This indicates that the critical wind speed of stalk breaking is a superior way to determine the stalk lodging resistance. These results suggest that, in the late growth stage, the decrease in the stalk mechanical strength is an important reason for the decrease in the critical wind speed of stalk breaking and the increase in the lodging rate.

13.
Sci Rep ; 10(1): 15378, 2020 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-32958804

RESUMO

Marginal superiority is a common phenomenon in crops, and is caused by the competitiveness of individual plant for resources and crop adaptability to crowded growth conditions. In this study, in order to clarify the response of marginal superiority to maize morphology and plant-density tolerance, field experiments without water and nutrition stress were conducted at Qitai Farm in Xinjiang, China, in 2013-2014 and 2016-2019. The results showed that no more than three border rows of all the cultivars had marginal superiority under high density, about 90% of all the cultivars had no more than two border row that had marginal superiority and a significant negative correlation was observed between marginal superiority and population grain yield (first border row: y = - 2.193x + 213.9, p < 0.05; second border row: y = - 2.076x + 159.2, p < 0.01). Additionally, marginal superiority was found to have a significant positive relationship with plant density (first border row: y = 6.049x + 73.76, p < 0.01; second border row: y = 1.88x + 95.41, p < 0.05) and the average leaf angle above the ear (first border row: y = 2.306x + 103.1, p < 0.01). These results indicated that the smaller the leaf angle above the ear, the weaker the marginal superiority and the higher the grain yield. It suggests that the magnitude of marginal superiority in the border rows can be an indicator for plant-density tolerance under high density. What's more, cultivars with small leaf angle above the ear can be selected to weaken the marginal superiority and improve grain yield under high plant density. Conversely, cultivars with a large leaf angle above the ear can be selected to achieve higher individual yield in intercropping systems with no more than four rows alternated with other crops.


Assuntos
Zea mays/crescimento & desenvolvimento , Agricultura/métodos , Biomassa , China , Produtos Agrícolas/crescimento & desenvolvimento , Folhas de Planta/crescimento & desenvolvimento , Água
14.
Int J Biometeorol ; 64(5): 827-839, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32040625

RESUMO

The stability of maize production is essential to global food security. Climate factors, such as temperature, precipitation, and solar radiation, directly affect the development of maize plants and hence the final grain yield. In this study, we investigated the spatial distributions and temporal trends of agro-climatic indices and severe weather indicators during the actual growing season for summer maize in Huanghuaihai region of China. The results showed that during the growing season, accumulated effective thermal time had significantly increased. From R3 to R6, accumulated effective thermal time, effective precipitation, and photosynthesis active radiation all showed an increasing trend, with the rate of 20.3 °C day, 1.1 mm, and 7.3 MJ m-2 per decade, respectively. From VE to R3, most of the study years showed a > 50% ratio of high-temperature days to subtotal days and > 7 consecutive days without available precipitation. During most of the study years, there were at least 0.5 thunderstorm events from V6 to VT stage in the locations of study; days with strong winds accounted for more than half the subtotal days during the V6-VT stage. And potential risk of lodging may be reduced by the decrease in days with strong wind. The results of this study could be used in optimizing agricultural management in summer maize production in order to take advantage of beneficial climatic elements while combating adverse climatic elements.


Assuntos
Mudança Climática , Zea mays , Agricultura , China , Clima Extremo , Estações do Ano
15.
Sci Rep ; 9(1): 4532, 2019 03 14.
Artigo em Inglês | MEDLINE | ID: mdl-30872703

RESUMO

Carcinoma metastasis is triggered by a subpopulation of circulating tumor cells (CTCs). And single immune checkpoint therapy is not good enough to inhibit CTC-induced metastasis. Here, we demonstrate that simultaneously blocking CD274 (programmed death ligand 1, PD-L1 or B7-H1) and CD47 checkpoints which were respectively signal of "don't find me" and "don't eat me" on CTCs by corresponding antibodies could enhance the inhibition tumor growth than single CD274 or CD47 antibody alone. In vitro flow cytometry data proved that CD47 and CD274 were overexpressed on the tested mouse tumor cell lines. The antibodies could effectively block the expressions of CD47 and CD274 on the cell surface and stably attached to tumor cell surface for several hours. The simultaneous blockade on both CD47 and CD274 checkpoints inhibited tumor growth and CTCs metastasis more potently than a single antibody inhibition or blank control on 4T1 tumor mouse model in vivo. Our results demonstrated that simultaneous dual targeting immune checkpoints, i.e., CD47 and CD274, by using specific antibodies may be more effective as an immunotherapeutics on CTCs than a CD47 or CD274 alone.


Assuntos
Anticorpos/imunologia , Antígeno B7-H1/imunologia , Antígeno CD47/imunologia , Neoplasias/terapia , Células Neoplásicas Circulantes/imunologia , Animais , Antígeno B7-H1/metabolismo , Antígeno CD47/metabolismo , Linhagem Celular Tumoral , Feminino , Imunoterapia , Células Matadoras Naturais/citologia , Células Matadoras Naturais/imunologia , Células Matadoras Naturais/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Células Neoplásicas Circulantes/metabolismo , Linfócitos T/citologia , Linfócitos T/imunologia , Linfócitos T/metabolismo , Transplante Homólogo
16.
Sci Rep ; 9(1): 3635, 2019 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-30842514

RESUMO

Matching of maize growth with solar radiation is of great importance for achieving high yield. We conducted experiments using different maize cultivars and planting densities under different solar radiations during grain filling to quantitatively analyze the relationships among these factors. We found that a decrease in solar radiation after silking caused a drop in maize grain yield and biomass, with lower solar radiation intensities leading to worse grain yields and biomass. Cultivar ZD958 was more sensitive to solar radiation changes than cultivar XY335; slight decreases in solar radiation (i.e., 15% shading) caused significant declines in ZD958 grain yield. When total solar radiation during grain filling was less than 486.9 MJ m-2 for XY335 and less than 510.9 MJ m-2 for ZD958, the two cultivars demonstrated high yields at lower planting density of 7.5 × 104 plants ha-1; average yields were 13.36 and 11.09 Mg ha-1, respectively. When radiation intensities were higher than 549.5 MJ m-2 for XY335 and higher than 605.8 MJ m-2 for ZD958, yields were higher at a higher planting density of 12 × 104 plants ha-1, with average yields of 20.58 Mg ha-1 for XY335 and 19.65 Mg ha-1 for ZD958.


Assuntos
Agricultura/métodos , Fotossíntese , Energia Solar , Zea mays/crescimento & desenvolvimento , Zea mays/fisiologia , Biomassa , Luz , Zea mays/efeitos da radiação
17.
Mol Pharm ; 16(5): 2235-2248, 2019 05 06.
Artigo em Inglês | MEDLINE | ID: mdl-30896172

RESUMO

Dual-targeted nanoparticles are gaining increasing importance as a more effective anticancer strategy by attacking double key sites of tumor cells, especially in chemophotodynamic therapy. To retain the nuclei inhibition effect and enhance doxorubicin (DOX)-induced apoptosis by mitochondrial pathways simultaneously, we synthesized the novel nanocarrier (HKH) based on hollow carbon nitride nanosphere (HCNS) modified with hyaluronic acid (HA) and the mitochondrial localizing peptide D[KLAKLAK]2 (KLA). DOX-loaded HKH nanoparticles (HKHDs) showed satisfactory drug-loading efficiency, excellent solubility, and very low hemolytic effect. HA/CD44 binding and electrostatic attraction between positively charged KLA and A549 cells facilitated HKHD uptake via the endocytosis mechanism. Acidic microenvironment, hyaluronidase, and KLA targeting together facilitate doxorubicin toward the mitochondria and nuclei, resulting in apoptosis, DNA intercalation, cell-cycle arrest at the S phase, and light-induced reactive oxygen species production. Intravascular HKHD inhibited tumor growth in A549-implanted mice with good safety. The present study, for the first time, systemically reveals biostability, targetability, chemophotodynamics, and safety of the functionalized novel HKHD.


Assuntos
Núcleo Celular , Doxorrubicina , Sistemas de Liberação de Medicamentos , Mitocôndrias , Nanosferas , Nitrilas , Fotoquimioterapia , Animais , Feminino , Humanos , Camundongos , Células A549 , Peptídeos Catiônicos Antimicrobianos/química , Apoptose/efeitos dos fármacos , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Doxorrubicina/química , Doxorrubicina/farmacologia , Doxorrubicina/uso terapêutico , Sistemas de Liberação de Medicamentos/métodos , Liberação Controlada de Fármacos , Endocitose/efeitos dos fármacos , Receptores de Hialuronatos/metabolismo , Ácido Hialurônico/química , Camundongos Endogâmicos BALB C , Camundongos Nus , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Nanosferas/química , Nitrilas/química , Fotoquimioterapia/métodos , Espécies Reativas de Oxigênio/metabolismo , Pontos de Checagem da Fase S do Ciclo Celular/efeitos dos fármacos , Solubilidade , Distribuição Tecidual , Carga Tumoral/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
18.
EBioMedicine ; 42: 281-295, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30878596

RESUMO

BACKGROUND: Treatment multiple tumors by immune therapy can be achieved by mobilizing both innate and adaptive immunity. The programmed death ligand 1 (PD-L1; or CD274, B7-H1) is a critical "don't find me" signal to the adaptive immune system. Equally CD47 is a critical "don't eat me" signal to the innate immune system and a regulator of the adaptive immune response. METHOD: Both of CD47 and PD-L1 are overexpressed on the surface of cancer cells to enable to escape immune-surveillance. We designed EpCAM (epithelial cell adhesion molecule)-targeted cationic liposome (LPP-P4-Ep) containing si-CD47 and si-PD-L1 could target high-EpCAM cancer cells and knockdown both CD47 and PD-L1 proteins. FINDINGS: Efficient silencing of CD47 and PD-L1 versus single gene silencing in vivo by systemic administration of LPP-P4-Ep could significantly inhibited the growth of solid tumors in subcutaneous and reduced lung metastasis in lung metastasis model. Target delivery of the complexes LPP-P4-Ep increased anti-tumor T cell and NK cell response, and release various cytokines including IFN-γ and IL-6 in vivo and in vitro. INTERPRETATION: This multi-nanoparticles showed significantly high-EpCAM tumor targeting and lower toxicity, and enhanced immune therapeutic efficacy. Our data indicated that dual-blockade tumor cell-specific innate and adaptive checkpoints represents an improved strategy for tumor immunotherapy. FUND: This research supported by the Ministry of Science and Technology of the People's Republic of China (grant number 2015CB931804); the National Natural Science Foundation of China (NSFC, grant numbers 81703555, U1505225 and 81773063), and the China Postdoctoral Science Foundation (grant number 2017 M620268).


Assuntos
Imunidade Adaptativa , Antígeno B7-H1/metabolismo , Antígeno CD47/metabolismo , Citocinas/metabolismo , Imunidade Inata , Neoplasias/imunologia , Neoplasias/metabolismo , Biomarcadores , Citotoxicidade Imunológica , Humanos , Imuno-Histoquímica , Neoplasias/patologia , Linfócitos T/imunologia , Linfócitos T/metabolismo
19.
Int J Oncol ; 53(6): 2590-2604, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30280201

RESUMO

Metastasis accounts for the majority of cancer-related mortalities, and the complex processes of metastasis remain the least understood aspect of cancer biology. Metabolic reprogramming is associated with cancer cell survival and metastasis in a hostile envi-ronment with a limited nutrient supply, such as solid tumors. Little is known regarding the differences of bioenergetic adaptation between primary tumor cells and metastatic tumor cells in unfavorable microenvironments; to clarify these differences, the present study aimed to compare metabolic reprogramming of primary tumor cells and metastatic tumor cells. SW620 metastatic tumor cells exhibited stronger bioenergetic adaptation in unfavorable conditions compared with SW480 primary tumor-derived cells, as determined by the sustained elevation of glycolysis and regulation of the cell cycle. This remarkable glycolytic ability of SW620 cells was associated with high expression levels of hexokinase (HK)1, HK2, glucose transporter type 1 and hypoxia-inducible factor 1α. Compared with SW480 cells, the expression of cell cycle regulatory proteins was effectively inhibited in SW620 cells to sustain cell survival when there was a lack of energy. Furthermore, SW620 cells exhibited a stronger mesenchymal phenotype and stem cell characteristics compared with SW480 cells; CD133 and CD166 were highly expressed in SW620 cells, whereas expression was not detected in SW480 cells. These data may explain why metastatic cancer cells exhibit greater microenvironmental adaptability and survivability; specifically, this may be achieved by upregulating glycolysis, optimizing the cell cycle and reprogramming cell metabolism. The present study may provide a target metabolic pathway for cancer metastasis therapy.


Assuntos
Trifosfato de Adenosina/metabolismo , Neoplasias do Colo/patologia , Glicólise , Células-Tronco Neoplásicas/metabolismo , Animais , Ciclo Celular , Linhagem Celular Tumoral , Sobrevivência Celular , Neoplasias do Colo/genética , Neoplasias do Colo/metabolismo , Metabolismo Energético , Regulação Neoplásica da Expressão Gênica , Transportador de Glucose Tipo 1/genética , Transportador de Glucose Tipo 1/metabolismo , Hexoquinase/genética , Hexoquinase/metabolismo , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Potencial da Membrana Mitocondrial , Camundongos , Metástase Neoplásica , Transplante de Neoplasias
20.
Ying Yong Sheng Tai Xue Bao ; 22(9): 2337-42, 2011 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-22126045

RESUMO

To understand the accumulated temperature (ACT) demand of maize for its normal maturation among years and regions as well as the use efficiency of local ACT, a group of work-net field experiments was conducted at 55 sites in 28 regions of Northeast China spring maize planting area (40 degrees 07'-48 degrees 08' N) in 2007-2009, taking an eurychoric maize variety Zhengdan 958 as test object. The meteorological conditions in the area had large difference. In the same regions, the active accumulated temperature above 10 degrees C in whole corn growth season (ACT10 for short) demand of Zhengdan 958 for completing its whole growth and development process had little difference among different years (P > 0.1). However, in different regions, this demand differed significantly (P < 0. 001) in the same years, with the largest difference occurred from seedling stage to emergence stage, followed by at post-silking stage, and the least at pre-silking stage. The maturity degree of Zhengdan 958 had significant correlations with local heat conditions, and there was a linear relationship between use efficiency and latitude. Zhengdan 958 could be safely matured in the regions with the ACT10 being more than 3000 degrees C, and had a risk of immaturity in the regions with the ACT10 less than 3000 degrees C. In conclusion, under certain meteorological conditions, the ACT demand of Zhengdan 958 for completing its growth process was relatively stable, and, due to the self physiological adjusting, the ACT10 demand of Zhengdan 958 at its different growth stages showed a significant difference among different regions.


Assuntos
Ecossistema , Temperatura , Zea mays/crescimento & desenvolvimento , China , Luz Solar , Zea mays/classificação
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