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1.
Respir Res ; 22(1): 149, 2021 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-33985501

RESUMO

BACKGROUND: To investigate whether the administration of hydrogen/oxygen mixture was superior to oxygen in improving symptoms in patients with acute exacerbation of chronic obstructive pulmonary disease (AECOPD). METHODS: This prospective, randomized, double-blind, controlled clinical trial in 10 centres enrolled patient with AECOPD and a Breathlessness, Cough, and Sputum Scale (BCSS) score of at least 6 points. Eligible patients were randomly assigned (in a 1:1 ratio) to receive either hydrogen/oxygen mixture or oxygen therapy. Primary endpoint was the change from baseline in BCSS score at day 7. Adverse events (AEs) were recorded to evaluate safety. RESULTS: Change of BCSS score in Hydrogen/oxygen group was larger than that in Oxygen group (- 5.3 vs. - 2.4 point; difference: - 2.75 [95% CI - 3.27 to - 2.22], meeting criteria for superiority). Similar results were observed in other time points from day 2 through day 6. There was a significant reduction of Cough Assessment Test score in Hydrogen/oxygen group compared to control (- 11.00 vs. - 6.00, p < 0.001). Changes in pulmonary function, arterial blood gas and noninvasive oxygen saturation did not differ significantly between groups as well as other endpoints. AEs were reported in 34 (63.0%) patients in Hydrogen/oxygen group and 42 (77.8%) in Oxygen group. No death and equipment defects were reported during study period. CONCLUSIONS: The trial demonstrated that hydrogen/oxygen therapy is superior to oxygen therapy in patient with AECOPD with acceptable safety and tolerability profile. TRIAL REGISTRATION: Name of the registry: U.S National Library of Medicine Clinical Trials; Trial registration number: NCT04000451; Date of registration: June 27, 2019-Retrospectively registered; URL of trial registry record: https://www.clinicaltrials.gov/ct2/show/study/NCT04000451?term=04000451&draw=2&rank=1 .


Assuntos
Hidrogênio/administração & dosagem , Pulmão/fisiopatologia , Oxigenoterapia , Doença Pulmonar Obstrutiva Crônica/terapia , Administração por Inalação , Idoso , China , Progressão da Doença , Método Duplo-Cego , Feminino , Humanos , Hidrogênio/efeitos adversos , Masculino , Pessoa de Meia-Idade , Oxigenoterapia/efeitos adversos , Estudos Prospectivos , Doença Pulmonar Obstrutiva Crônica/diagnóstico , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Fatores de Tempo , Resultado do Tratamento
2.
J Chem Phys ; 154(5): 054903, 2021 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-33557527

RESUMO

The external voltage-driven polymer translocation through a conical pore (with a large opening at the entry and a small tip at the exit) is studied by using the Langevin dynamics simulation in this paper. The entire translocation process is divided into an approaching stage and a threading stage. First, the approaching stage starts from the polymer entering the large opening and ends up at a terminal monomer reaching the pore tip. In this stage, the polymer will undergo the conformation adjustment to fit the narrowed cross-sectional area of the pore, leading to three approaching modes: the non-stuck mode with a terminal monomer arriving at the pore tip smoothly, the weak-stuck mode for the polymer stuck inside the pore for a short duration with minor conformational adjustments, and the strong-stuck mode with major conformational changes and a long duration. The approaching times (the duration of the approaching stage) of the three approaching modes show different behavior as a function of the pore apex angle. Second, the threading stage describes that the polymer threads through the pore tip with a linear fashion. In this stage, an increase in the apex angle causes the reduction of the threading time (the duration of the threading stage) due to the increase in the driving force with the apex angle at the tip. Moreover, we also find that with the increase in the apex angle or the polymer length, the polymer threading dynamics will change from the quasi-equilibrium state to the non-equilibrium state.

3.
Macromol Rapid Commun ; 41(15): e2000260, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32648310

RESUMO

Polymerization-induced self-assembly has been demonstrated to be a powerful strategy for fabricating polymeric nanoparticles in the last two decades. However, the stringent requirements for the monomers greatly limit the chemical versatility of PISA-based functional nanoparticles and expanding the monomer family of PISA is still highly desirable. Herein, a camptothecin analogue (CPTM) is first used as the monomer in PISA. Prodrug nanoparticles with reduction-responsive camptothecin release behavior are fabricated at 10% solid concentration (100 mg g-1 ). Poly(N-(2-hydroxypropyl)methacrylamide) (PHPMA) and poly(2-(diethylamino)ethyl methacrylate) (PDEAEMA) are used as the macro RAFT agents to comediate the RAFT dispersion polymerization of CPTM in ethanol to produce the PHPMA/PDEAEMA-stabilized nanoparticles. The PDEAEMA chains become hydrophobic and are in the collapsed state at physiological pH values. In contrast, in the vicinity of an acidic tumor, the tertiary amine groups of PDEAEMA chains are rapidly protonated, leading to fast hydrophobic-hydrophilic transitions and charge reversal. Such fast charge-reversal results in enhanced cancer cell internalization of the prodrug nanoparticles, thus achieving superior anticancer efficacy.


Assuntos
Portadores de Fármacos/química , Nanopartículas/química , Pró-Fármacos/química , Sobrevivência Celular/efeitos dos fármacos , Liberação Controlada de Fármacos , Etanol/química , Células HeLa , Humanos , Concentração de Íons de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Metacrilatos/química , Microscopia Eletrônica de Transmissão , Nanopartículas/ultraestrutura , Nylons/química , Polimerização , Polímeros/química , Ácidos Polimetacrílicos/química , Água/química
4.
Bioconjug Chem ; 30(2): 284-292, 2019 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-30543405

RESUMO

The rapid developments of gene therapy are benefit from the construction of efficient gene vectors, which help therapy genes efficiently overcome the barriers in the transport and transfection. Condensing DNA into nanoparticles is a crucial role in gene transfection, and the electrostatic interactions of synthetic cationic liposomes and cationic polymers with DNA are generally used for condensing DNA. Recent research has shown that the introduction of the hydrophobic interaction, hydrogen bonding, and coordinative interactions to the gene delivery vectors is also very important for DNA condensation, delivery, and transfection. This review focuses on the four types of interactions in condensed DNA nanoparticles, which could provide a new perspective for improving gene transfection efficacy.


Assuntos
DNA/administração & dosagem , DNA/química , Técnicas de Transferência de Genes , Animais , Cátions/química , DNA/genética , Humanos , Ligação de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Lipossomos/química , Nanopartículas/química , Conformação de Ácido Nucleico , Polímeros/química , Eletricidade Estática , Transfecção/métodos
5.
J Chem Phys ; 150(2): 024904, 2019 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-30646715

RESUMO

The polymer translocation through a spherical pore is studied using the Langevin dynamics simulation. The translocation events are classified into two types: one is the trapped translocation in which the entire polymer is trapped in the pore and the other is the non-trapped translocation where the pore cannot hold the whole polymer. We find that the trapped translocation is favored at large spheres and small external voltages. However, the monomer-pore attraction would lead to the non-monotonic behavior of the trapped translocation possibility out of all translocation events. Moreover, both the trapped and non-trapped translocation times are dependent on the polymer length, pore size, external voltage, and the monomer-pore attraction. There exist two pathways for the polymer in the trapped translocation: an actively trapped pathway for the polymer trapped in the pore before the head monomer arrives at the pore exit, and a passively trapped pathway for the polymer trapped in the pore while the head monomer is struggling to move out of the pore. The studies of trapped pathways can provide a deep understanding of the polymer translocation behavior.

6.
J Cell Physiol ; 233(1): 79-87, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28181235

RESUMO

Transmembrane protein 88 (TMEM88), a newly discovered protein localized on the cell membrane. Recent studies showed that TMEM88 was involved in the regulation of several types of cancer. TMEM88 was expressed at significantly higher levels in breast cancer (BC) cell line than in normal breast cell line with co-localized with Dishevelled (DVL) in the cytoplasm of BC cell line. TMEM88 silencing in the ovarian cancer cell line CP70 resulted in significant upregulation of Wnt downstream genes (c-Myc, cyclin-D1) and other Wnt target genes including JUN, PTIX2, CTNNB1 (ß-catenin), further supporting that TMEM88 inhibits canonical Wnt signaling pathway. Wnt signaling pathway has been known to play important roles in many diseases, especially in cancer. For instance, hepatocellular carcinoma (HCC) has become one of the most common tumors harboring mutations in the Wnt signaling pathway. As the inhibitor of Wnt signaling, TMEM88 has been considered to act as an oncogene or a tumor suppressor. Up-regulated TMEM88 or gene therapy approaches could be an effective therapeutic approach against tumor as TMEM88 inhibits Wnt signaling through direct interaction with DVL. Here, we review the current knowledge on the functional role and potential clinical application of TMEM88 in the control of various cancers. Highlights Wnt signaling displays an important role in several pathogenesis of cancer. Wnt signaling pathway is activated during cancer development. TMEM88 has an impact on cancer by inhibiting canonical Wnt signaling. We discuss the importance and new applications of TMEM88 in cancer therapy.


Assuntos
Transformação Celular Neoplásica/metabolismo , Proteínas de Membrana/metabolismo , Neoplasias/metabolismo , Via de Sinalização Wnt , Animais , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/patologia , Progressão da Doença , Proteínas Desgrenhadas/genética , Proteínas Desgrenhadas/metabolismo , Regulação Neoplásica da Expressão Gênica , Terapia Genética/métodos , Humanos , Proteínas de Membrana/genética , Neoplasias/genética , Neoplasias/patologia , Neoplasias/terapia
7.
BMC Pulm Med ; 17(1): 196, 2017 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-29233130

RESUMO

BACKGROUND: Acute exacerbation of chronic obstructive pulmonary disease (AECOPD) is the most common reason for the hospitalization and death of pulmonary patients. The use of antibiotics as adjuvant therapy for AECOPD, however, is still a matter of debate. METHODS: In this study, we searched the PubMed, EmBase, and Cochrane databases for randomized controlled trials published until September 2016 that evaluated the use of antibiotics for AECOPD treatment. The major outcome variables were clinical cure rate and adverse effects. The microbiological response rate, relapse of exacerbation, and mortality were also analysed. A random-effect network was used to assess the effectiveness and tolerance of each antibiotic used for AECOPD treatment. RESULTS: In this meta-analysis, we included 19 articles that assessed 17 types of antibiotics used in 5906 AECOPD patients. The cluster ranking showed that dirithromycin had a high clinical cure rate with a low rate of adverse effects. Ofloxacin, ciprofloxacin, and trimethoprim-sulfamethoxazole had high clinical cure rates with median rates of adverse effects. In terms of the microbiological response rate, only doxycycline was significantly better than placebo (odds ratio (OR), 3.84; 95% confidence interval (CI), 1.96-7.54; p < 0.001). There were no other significant results with respect to the frequency of recurrence or mortality. CONCLUSIONS: Our study indicated that dirithromycin is adequate for improving the clinical cure rate of patients with AECOPD with few adverse effects. Ofloxacin, ciprofloxacin, and trimethoprim-sulfamethoxazole are also recommended for disease treatment. However, caution should still be exercised when using antibiotics to treat AECOPD. Trial Registration Not applicable.


Assuntos
Antibacterianos/farmacologia , Doença Pulmonar Obstrutiva Crônica , Humanos , Doença Pulmonar Obstrutiva Crônica/diagnóstico , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico , Resultado do Tratamento
8.
J Cell Mol Med ; 20(7): 1276-86, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-26915688

RESUMO

Small guanosine triphosphate (GTP)-binding protein RhoB is an important stress sensor and contributes to the regulation of cytoskeletal organization, cell proliferation and survival. However, whether RhoB is involved in the hypoxic response and action of glucocorticoid (GC) is largely unknown. In this study, we investigated the effects of hypoxia or/and GC on the expression and activition of RhoB in the lung of rats and human A549 lung carcinoma cells, and further studied its mechanism and significance. We found that hypoxia and dexamethasone (Dex), a synethic GC, not only significantly increased the expression and activation of RhoB independently but also coregulated the expresion of RhoB in vitro and in vivo. Up-regulation of RhoB by hypoxia was in part through stabilizing the RhoB mRNA and protein. Inhibiting hypoxia-activated hypoxia-inducible transcription factor-1α (HIF-1α), c-Jun N-terminal kinase (JNK) or extracellular signal-regulated kinase (ERK) with their specific inhibitors significantly decreased hypoxia-induced RhoB expression, indicating that HIF-1α, JNK and ERK are involved in the up-regulation of RhoB in hypoxia. Furthermore, we found that knockdown of RhoB expression by RhoB siRNA not only significantly reduced hypoxia-enhanced cell migration and cell survival in hypoxia but also increased the sensitivity of cell to paclitaxel (PTX), a chemotherapeutic agent, and reduced Dex-enhanced resistance to PTX-chemotherapy in A549 cells. Taken together, the novel data revealed that hypoxia and Dex increased the expression and activation of RhoB, which is important for hypoxic adaptation and hypoxia-accelerated progression of lung cancer cells. RhoB also enhanced the resistance of cell to PTX-chemotherapy and mediated the pro-survival effect of Dex.


Assuntos
Glucocorticoides/farmacologia , Pulmão/metabolismo , Regulação para Cima/efeitos dos fármacos , Proteína rhoB de Ligação ao GTP/metabolismo , Células A549 , Animais , Antineoplásicos/farmacologia , Hipóxia Celular/efeitos dos fármacos , Hipóxia Celular/genética , Movimento Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Dexametasona/farmacologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Pulmão/efeitos dos fármacos , Modelos Biológicos , Estabilidade de RNA/efeitos dos fármacos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos Sprague-Dawley , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Proteína rhoB de Ligação ao GTP/genética
9.
J Mater Chem B ; 12(23): 5628-5644, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38747238

RESUMO

Hydrogels with strong adhesion to wet tissues are considered promising for wound dressings. However, the clinical application of adhesive hydrogel dressing remains a challenge due to the issues of secondary damage during dressing changes. Herein, we fabricated an adhesion-switchable hydrogel formed with poly(acrylamide)-co-poly(N-isopropyl acrylamide), quaternary ammonium chitosan and tannic acid. This hydrogel forms instant and robust adhesion to the skin at body temperature. However, as the temperature rises above the lower critical solution temperature (LCST), the hydrogel loses its adhesion towards the wound area due to the temperature-dependent volume phase transition of the copolymer, occurring around 45 °C. Consequently, the designed hydrogel can be easily detached from adhered tissues upon demand, providing a facile and effective method for painless dressing changes without secondary damage. This hydrogel holds great promise for long-term application in wound dressings.


Assuntos
Bandagens , Quitosana , Hidrogéis , Hidrogéis/química , Hidrogéis/farmacologia , Animais , Quitosana/química , Resinas Acrílicas/química , Taninos/química , Taninos/farmacologia , Camundongos , Cicatrização/efeitos dos fármacos , Temperatura
10.
Ying Yong Sheng Tai Xue Bao ; 35(1): 212-218, 2024 Jan.
Artigo em Zh | MEDLINE | ID: mdl-38511458

RESUMO

We investigated the effects and mechanisms of nitrogen additions (0, 1, 2, 4, 8, 16, 24, 32 g N·m-2·a-1) on contents of anion and cation in rhizosphere soil, bulk soil, and mixed rhizosphere and bulk soil in the heavily salinized grassland in the agro-pastoral ecotone of North China. The results showed that pH of rhizosphere, mixed and bulk soils decreased significantly with the increases of nitrogen addition levels. Moreover, pH of three soil types under the 32 g N·m-2·a-1 treatment decreased by 1.2, 0.9, and 0.6, respectively, while pH of rhizosphere soil decreased by 0.44 compared with the bulk soil. Na+ content of rhizosphere, mixed and bulk soils significantly decreased, while the NO3- content significantly increased. The proportion of Na+ content in total soluble salt content in rhizosphere soil decreased by 14% and that in bulk soil decreased by 12% after the 32 g N·m-2·a-1 addition. NO3- content increased by 29% in rhizosphere soil and by 26% in bulk soil. There was significant negative correlation between pH and NO3- content, and significant positive correlation between pH and Na+ content. The total soluble salt content of rhizosphere soil under the 32 g N·m-2·a-1 treatment was significantly reduced by 31.5%. Collectedly, nitrogen deposition could reduce soil pH and total soluble salt content of rhizosphere soil and alleviate saline-alkali stress.


Assuntos
Rizosfera , Solo , Solo/química , Pradaria , Nitrogênio/análise , Ânions , Cátions , China , Microbiologia do Solo
11.
Zhonghua Nan Ke Xue ; 19(9): 806-10, 2013 Sep.
Artigo em Zh | MEDLINE | ID: mdl-24386859

RESUMO

OBJECTIVE: To investigate the role of the HoxA13 gene from the HOX family in the development of hypospadias by detecting the transcription and expression of HoxA13 in the prepuce and urethral plate of hypospadias patients. METHODS: We collected the tissues from the prepuce and urethral plate of 30 hypospadias patients aged 3.3 - 11.6 years, the prepuce of 10 phimosis children aged 3.1 - 10.4 years and the urethra of 10 penile carcinoma patients aged 48.1 - 75.6 years with no urethral involvement, the latter 20 taken as controls. We divided the tissue samples into a distal, an intermedial, a proximal and a control group, and detected the expressions of HoxA13 mRNA and protein in different groups by RT-PCR and immunohistochemistry. RESULTS: RT-PCR showed that the HoxA13 mRNA expressions in the prepuce and urethral plate were significantly higher in the control group (1.409 +/- 0.441 and 1.270 +/- 0.209) than in the intermedial (0.848 +/- 0.338 and 0.684 +/- 0.228) and proximal group (0.497 +/- 0.218 and 0.464 +/- 0.164) (P < 0.05 or P < 0.01), and so were they in the distal (1.071 +/- 0.342 and 1.054 +/- 0.189) than in the proximal group (P < 0.05). Immunohistochemistry revealed that the HoxA13 protein expressions in the prepuce and urethral plate were remarkably higher in the control group (12 050 +/- 4 112 and 13 420 +/- 2 636) than in the intermedial (5 217 +/- 1 993 and 5 238 +/- 3 065) and proximal group (2 095 +/- 1 591 and 2 238 +/- 2 217) (P < 0.05 or P < 0.01), and so were they in the distal (8 223 +/- 3 212 and 10 450 +/- 2 123) than in the proximal group (P < 0.05). CONCLUSION: The transcription and expression of HoxA13 in the prepuce and urethral plate of hypospadias patients are closely related with the abnormal position of the urethral meatus, and their abnormal expressions may affect the development and formation of the urethra.


Assuntos
Prepúcio do Pênis/metabolismo , Proteínas de Homeodomínio/metabolismo , Hipospadia/metabolismo , Idoso , Estudos de Casos e Controles , Criança , Pré-Escolar , Proteínas de Homeodomínio/genética , Humanos , Hipospadia/genética , Masculino , Pessoa de Meia-Idade , Uretra/metabolismo
12.
Chin J Cancer Res ; 25(5): 593-9, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24255584

RESUMO

OBJECTIVES: To investigate the effects of adenovirus-mediated inducible nitric oxide synthase gene transfection on bladder transitional cell carcinoma T24 cells, and to provide novel insights and approaches to clinical therapies against bladder transitional cell carcinoma. METHODS: Firstly, construct recombinant adenovirus vector pAd-iNOS of iNOS, followed by transfection of pAd-iNOS into HECK293 packaging cells. Thirdly, harvest recombinant adenovirus rAd-iNOS after amplification and purification procedures. Finally, transfect the recombinant adenovirus rAd-iNOS into human bladder carcinoma T24 cells and examine the effect of rAd-iNOS transfection on apoptosis of T24 and possible mechanism. RESULTS: As shown by this study, the recombinant adenovirus rAd-iNOS was constructed successfully. The virus titer was 5.8×10(8) PFU/mL and recombinant was verified by PCR analysis. Transfection of adenovirus rAd-iNOS into T24 cells could induce secretion of high NO concentration, P53 protein expression up-regulation, as well as promotion of T24 cell apoptosis. CONCLUSIONS: The transfection of human bladder carcinoma T24 cells from recombinant adenovirus rAd-iNOS was confirmed to induce intracellular iNOS over-expression, high production of NO, up-regulation of intracellular P53 expression and promotion of cell apoptosis.

13.
Ying Yong Sheng Tai Xue Bao ; 34(1): 67-74, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36799378

RESUMO

We explored the impacts of nitrogen (N) inputs and the rhizosphere effect on the properties of rhizosphere and bulk soils in a salinized grassland in Northern Shanxi under N addition rates of 0, 1, 2, 4, 8, 16, 24 and 32 g N·m-2·a-1. The results showed that N addition significantly decreased soil pH, but significantly increased Ca2+, NO3--N and inorganic nitrogen contents in rhizosphere and bulk soil. With the increases of N addition rates, the contents of Ca2+, NO3--N, inorganic nitrogen in rhizosphere and bulk soils and total nitrogen in rhizosphere soil increased gradually, whereas the contents of Na+, K+, Mg2+, NH4+-N and amino acid in rhizosphere soil, and total nitrogen in bulk soil first increased and then decreased. Results of the principal component analysis showed that the responses of soil properties to low (≤8 g·m-2·a-1) and high nitrogen addition rates (>8 g·m-2·a-1) were significantly different. Compared with bulk soil, soil pH, the contents of organic acids and amino acids in rhizosphere soil were significantly lower by 0.71 units, 44.3% and 9.8%, respectively, while the contents of K+, Ca2+, Mg2+, NH4+-N, inorganic nitrogen, total carbon and total nitrogen in rhizosphere soil were significantly higher by 51.0%, 47.6%, 20.8%, 215.5%, 139.3%, 31.7% and 65.3%, respectively. These results indicated that rhizosphere effect on soil properties was stronger than that of nitrogen addition.


Assuntos
Rizosfera , Solo , Solo/química , Nitrogênio/análise , Pradaria , Microbiologia do Solo
14.
Adv Healthc Mater ; 12(21): e2203252, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37154112

RESUMO

Gene therapy holds great promise as an effective treatment for many diseases of genetic origin. Gene therapy works by employing cationic polymers, liposomes, and nanoparticles to condense DNA into polyplexes via electronic interactions. Then, a therapeutic gene is introduced into target cells, thereby restoring or changing cellular function. However, gene transfection efficiency remains low in vivo due to high protein binding, poor targeting ability, and substantial endosomal entrapment. Artificial sheaths containing PEG, anions, or zwitterions can be introduced onto the surface of gene carriers to prevent interaction with proteins; however, they reduce the cellular uptake efficacy, endosomal escape, targeting ability, thereby, lowering gene transfection. Here, it is reported that linking dipicolylamine-zinc (DPA-Zn) ions onto polyplex nanoparticles can produce a strong hydration water layer around the polyplex, mimicking the function of PEGylation to reduce protein binding while targeting cancer cells, augmenting cellular uptake and endosomal escape. The polyplexes with a strong hydration water layer on the surface can achieve a high gene transfection even in a 50% serum environment. This strategy provides a new solution for preventing protein adsorption while improving cellular uptake and endosomal escape.


Assuntos
Neoplasias , Zinco , Ligação Proteica , Polímeros/metabolismo , DNA/metabolismo , Cátions , Transfecção , Técnicas de Transferência de Genes , Polietilenoglicóis/metabolismo , Neoplasias/terapia
15.
Ying Yong Sheng Tai Xue Bao ; 33(3): 648-654, 2022 Mar.
Artigo em Zh | MEDLINE | ID: mdl-35524515

RESUMO

Global changes have profound impacts on the structure and function of terrestrial ecosystems. It is a prerequisite to realize the sustainable use of ecosystem to clarify the response and adaptation mechanism of ecosystems to global changes. Network of control experiment is an important way to understand the response and adaptation of the structure and function of ecosystems to global change factors at regional and global scales. The scientific top-level design is conducive to the integration, comparison and analysis of integrative network-data, and then supports the development of universal ecological theory. We comprehensively expounded the theoretical basis, methodological principles and brand-new concepts of experimental network design for future global change control experiment networks design from several aspects, such as research progress, development needs, innovative design and research prospects. Taking Chinese grassland ecosystems as an example, based on the concept of space reference points (mean point of water and heat), the innovative design technology system of China's grassland ecosystem networking experiment was proposed, in order to promote the development of networking research of control experiments at both regional and global scales in the future.


Assuntos
Ecossistema , Pradaria , China , Temperatura Alta , Água
16.
Ying Yong Sheng Tai Xue Bao ; 32(7): 2389-2396, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34313056

RESUMO

To explore the responses of soil net nitrogen (N) mineralization rate to precipitation varia-tion and nitrogen deposition in salinized grassland, we set precipitation manipulation and nitrogen addition experiments in the typical agro-pastoral ecotone saline-alkaline grassland of Northern Shanxi Province, China. The in situ soil net N mineralization rate was determined by top-cover buried PVC cylinder from May to September in 2019. The results showed that there were seasonal dynamics in soil net N mineralization rate. Soil net N mineralization rate was not affected by increase/decrease precipitation (±50%), nitrogen addition (10 g·m-2·a-1) or the combination of nitrogen addition and increase 50% precipitation treatments. The combination of nitrogen addition and 50% reduction of precipitation significantly improved soil net nitrification rate and net N mine-ralization rate by 10.8 and 8.6 times, respectively. Soil net nitrogen mineralization rate was positively related to soil water content, and negatively related to soil pH. The effects of nitrogen addition on soil nitrogen mineralization rate were dependent on precipitation conditions. Soil water content and pH were important factors regulating soil net nitrogen mineralization rate in the saline-alkaline grassland of Northern Shanxi Province. Therefore, to roundly assess the response model of soil N mine-ralization process to global change, it is necessary to consider the interaction of precipitation changes and nitrogen addition, and the soil physical and chemical properties of salinized grassland.


Assuntos
Nitrogênio , Solo , China , Pradaria , Nitrificação , Nitrogênio/análise
17.
Chin Med J (Engl) ; 134(18): 2166-2174, 2021 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-34553699

RESUMO

BACKGROUND: The effectiveness of bronchial thermoplasty (BT) has been reported in patients with severe asthma. This study compared the effects of BT and cryoballoon ablation (CBA) therapy on the airway smooth muscle (ASM). METHODS: Eight healthy male beagle dogs were included in this experiment. In the preliminary experiment, one dog received BT treatment for both lower lobe bronchus, another dog received CBA treatment for 7 s on the upper and lower lobe of right bronchus, and 30 s on the left upper and lower lobe. The treatments were performed twice at an interval of 1 month. In subsequent experiments, the right lower lobe bronchus was treated with BT, and the left lower lobe bronchus was treated with CBA. The effects of treatment were observed after 1 (n = 3) month and 6 months (n = 3). Hematoxylin-eosin staining, Masson trichrome staining, and immunohistochemical staining were used to compare the effects of BT and CBA therapy on the ASM thickness, collagen fibers synthesis, and M3 receptor expression after treatment. One-way analysis of variance with Dunnett post hoc test was used to analyze the differences among groups. RESULTS: In the preliminary experiment, the ASM ablation effect of 30-s CBA was equivalent to that of 7-s CBA (ASM thickness: 30.52 ±â€Š7.75 µm vs. 17.57 ±â€Š15.20 µm, P = 0.128), but the bronchial mucociliary epithelium did not recover, and large numbers of inflammatory cells had infiltrated the mucosal epithelium at 1-month post-CBA with 30-s freezing. Therefore, we chose 7 s as the CBA treatment time in our follow-up experiments. Compared with the control group (35.81 ±â€Š11.02 µm), BT group and CBA group (13.41 ±â€Š4.40 µm and 4.81 ±â€Š4.44 µm, respectively) had significantly decreased ASM thickness after 1 month (P < 0.001). Furthermore, the ASM thickness was significantly lower in the 1-month post-CBA group than in the 1-month post-BT group (P = 0.015). There was no significant difference in ASM thickness between the BT and CBA groups after six months (9.92 ±â€Š4.42 µm vs. 7.41 ±â€Š7.20 µm, P = 0.540). Compared with the control group (0.161 ±â€Š0.013), the average optical density of the ASM M3 receptor was significantly decreased in 6-month post-BT, 1-month post-CBA, and 6-month post-CBA groups (0.070 ±â€Š0.022, 0.072 ±â€Š0.012, 0.074 ±â€Š0.008, respectively; all P < 0.001). There was no significant difference in the average optical density of ASM M3 receptor between the BT and CBA therapy groups after six months (P = 0.613). CONCLUSIONS: CBA therapy effectively ablates the ASM, and its ablation effect is equivalent to that of BT with a shorter onset time. A neural mechanism is involved in both BT and CBA therapy.


Assuntos
Termoplastia Brônquica , Criocirurgia , Animais , Brônquios/cirurgia , Broncoscopia , Cães , Humanos , Masculino , Músculo Liso
18.
Ying Yong Sheng Tai Xue Bao ; 32(7): 2433-2439, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34313061

RESUMO

Grazing is the dominant land use way for natural grasslands. Different grazing intensities could affect soil stoichiometry in grasslands by influencing the selective feeding by livestock, litter input, and microbial community structure. In this study, a grazing experiment was carried out in a grassland of agro-pastoral ecotone in Northern China for three years (2017-2019). The concentrations of total carbon (TC), total nitrogen (TN), dissolved organic carbon (DOC), dissolved nitrogen (DN), microbial biomass carbon (MBC), and microbial biomass nitrogen (MBN) in soils were measured. We analyzed the stoichiometric characteristics of those parameters. The results showed that different grazing intensities (1, 2, 4 sheep·0.2 hm-2) had no significant effect on soil TC after three years. The moderate grazing intensity significantly reduced soil TN in 10-20 cm layer in 2019. The light, moderate, and heavy grazing intensities significantly increased soil C/N at 10-20 cm layer, while grazing intensities did not affect soil DOC, DN and DOC/DN. The soil DOC and DN content showed a decreasing trend with the increase of grazing intensity in 2019. It indicated that continuous high intensity grazing might reduce soil dissolved nutrients. The light grazing inten-sity increased soil MBC, while heavy grazing intensity reduced soil MBC significantly, with the increase of grazing year. Different grazing intensities did not affect soil MBN and MBC/MBN.


Assuntos
Pradaria , Solo , Animais , Biomassa , Carbono/análise , China , Nitrogênio/análise , Ovinos
19.
Zhonghua Yi Xue Za Zhi ; 90(8): 540-6, 2010 Mar 02.
Artigo em Zh | MEDLINE | ID: mdl-20367966

RESUMO

OBJECTIVE: To evaluate the efficacy and safety of oral theophylline versus placebo in patients with stable chronic obstructive pulmonary disease (COPD). METHODS: The databases Medline, Embase, Web of Science, Cochrane Central Register of Controlled Trials and Chinese Biomedical Database were retrieved by using the key words "Uniphyl or Theophylline or Theo-Dur or theo or Theotrim or Elixophyllin or Elixophyllin or Phyllocontin or aminophylline or Methylxanthine or nuelin or doxofylline" and "obstructive or bronchitis or pulmonary emphysema or bronchial hyperreactivity or COPD or COLD or emphysema" so as to search the materials about the randomized controlled clinical trials comparing the effectiveness of stable COPD treated by oral theophylline and placebo. A meta-analysis was conducted. For continuous variables, the results of individual studies were pooled using fixed-effect weighted mean difference (WMD) with a corresponding 95% confidence interval (CI). Where the results were expressed as dichotomous variables, the relative risk (RR) with 95%CI was calculated. RESULTS: Thirty-four documents about randomized controlled clinical trials, including a total of 2087 patients, from the retrieved 2010 documents accorded to the demand of enrollment. The results of meta-analysis showed that theophylline significantly improved the forced expiratory volume in 1 s, forced vital capacity and peak expiratory flow rate (WMD 0.09 L, 95%CI 0.09 - 0.09; WMD 0.14 L, 95%CI 0.13 - 0.14; WMD 17.0 L/min and 95%CI 6.9 - 27.2 respectively). Arterial oxygen tension and arterial carbon dioxide tension at rest both improved with treatment (WMD 2.89 mm Hg, 95%CI 1.11 - 4.66; WMD -2.05 mm Hg and 95%CI -3.59 to -1.42 respectively). Six-minute walk distance significantly improved (WMD 38.89 meters, 95%CI 21.55 - 56.22) in treatment group. The RR of acute exacerbations was smaller between both groups (RR 0.74, 95%CI 0.59 - 0.93). The RR of total adverse events was similar (RR 1.05, 95%CI 0.95 - 1.16) while RR of drug-related adverse events was greater (RR 2.54, 95%CI 1.37 - 4.70). And there was significant statistical difference. CONCLUSION: Compared with the placebo, theophylline can improve lung function, arterial blood gas tensions and walking distance while the incidence of drug-related adverse events is higher.


Assuntos
Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico , Teofilina/efeitos adversos , Teofilina/uso terapêutico , Administração Oral , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , Testes de Função Respiratória , Teofilina/administração & dosagem
20.
Ying Yong Sheng Tai Xue Bao ; 31(2): 417-423, 2020 Feb.
Artigo em Zh | MEDLINE | ID: mdl-32476333

RESUMO

As a natural disturbance agent, soil erosion could affect secondary distribution and species composition of soil seed bank. The composition, storage and distribution pattern of the soil seed banks in five different vegetation recovery areas, including bare ground (1), pine forest land (2-4) and secondary forest (5) in the typical red soil erosion area, were studied to explore the effects of soil erosion on soil seed bank during vegetation restoration. The results showed that a total of 21 species were recorded in the soil seed bank. Species richness was low, and dominated by herbaceous species. The density of soil seed bank varied from 56.7 to 793.3 seeds·m-2 and differed significantly among the sampling plots. Further, the density of soil seed bank decreased obviously with the increasing soil erosion intensity. The seed bank density of 0-2 cm soil layer increased along uphill, middle slope, and downhill. The soil seed banks of severely eroded and strongly eroded plots were mainly distributed in the 5-10 cm soil layer, with almost no seeds in 0-2 cm soil layer on the middle slope and uphill. Soil erosion made the distribution of soil seed bank to deeper soil layer, the accumulation of which will need a long time after vegetation restoration.


Assuntos
Banco de Sementes , Solo , Florestas , Sementes
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