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1.
Medicine (Baltimore) ; 102(45): e35782, 2023 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-37960814

RESUMO

RATIONALE: Dural arteriovenous fistulas (DAVFs) are rare cerebral abnormal arteriovenous anastomoses. It is uncommon for DAVFs with parkinsonism and dementia, so it is easily misdiagnosed. Neuroimaging examinations show that multifocal DAVFs are related to venous thrombosis and white matter changes, suggesting that cerebral circulatory disorders caused by venous hypertensive encephalopathy lead to dementia in patients. Digital subtraction angiography confirmed the diagnosis and subsequent treatment of DAVFs. PATIENT CONCERNS: We report 2 cases, one caused by bilateral white matter lesions and the other caused by bilateral thalamus lesions. Their symptoms are all manifested as progressive dementia and parkinsonism. DIAGNOSIS: They were diagnosed with dural arteriovenous fistulas by digital subtraction angiography. OUTCOMES: The first patient developed progressive cognitive impairment, 6 months later, the patient developed bedridden, incontinence, and severe cognitive function.The second patient became increasingly bedridden 3 months after discharge and died of aspiration pneumonia. LESSONS: There are few reports of progressive dementia and parkinsonism in DAVF patients, and neurologists should be vigilant to avoid misdiagnosing DAVF.


Assuntos
Malformações Vasculares do Sistema Nervoso Central , Demência , Transtornos Parkinsonianos , Humanos , Malformações Vasculares do Sistema Nervoso Central/diagnóstico , Demência/diagnóstico , Transtornos Parkinsonianos/diagnóstico
2.
Int J Gen Med ; 16: 4099-4107, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37720176

RESUMO

Background: Although numerous prognostic markers for cerebral venous thrombosis (CVT) have been reported, inconsistencies exist in their predictive values, leading to contradictory forecasts. This study was designed to develop a comprehensive clinical outcome prediction score for Chinese patients with CVT, integrating key prognostic markers to furnish an overall prognosis. Methods: Participants were selected from the CCC cohort, a multicenter study encompassing 26 tertiary hospitals across mainland China. Between January 2021 and May 2022, 170 patients with CVT were prospectively recruited. Potential prognostic markers were extracted from the CCC database and subsequently analyzed. Results: Age, diastolic blood pressure (DBP), neutrophil-to-lymphocyte ratio (NLR), and neuron-specific enolase (NSE) emerged as significant prognostic markers for CVT after a multivariate logistic analysis. Specific cut-off values were identified: Age > 27.5 years, DBP > 79.5 mmHg, NLR > 6.6, and NSE >16.5 ng/mL. The points assigned were: one each for age and NSE level, two for DBP, and three for NLR, based on the adjusted odds ratio. A positive correlation was found between the baseline CVT outcome score and the mRS at six months' follow-up. A CVT outcome score of 3.5 served as an effective cut-off value for predicting CVT clinical outcomes. Further analysis revealed that patients with CVT outcome scores > 3 exhibited significantly higher mRS scores than those with scores ≤ 3. Conclusion: This study led to the development of the CVT outcome score, consisting of age, DBP, NLR, and NSE level, specifically for Chinese patients with CVT. The baseline CVT outcome score positively correlated with the mRS score at the six-month follow-up. A CVT outcome score of > 3 serves as a reliable indicator to identify patients at a higher risk of unfavorable clinical outcomes. These patients may benefit from additional care and early interventions to avert potential deterioration.

3.
Biomolecules ; 12(12)2022 11 23.
Artigo em Inglês | MEDLINE | ID: mdl-36551160

RESUMO

The core-1 ß1-3galactosyltransferase-specific chaperone 1 (Cosmc) is a unique molecular chaperone of core-1 ß1-3galactosyltransferase(C1GALT1), which typically functions inside the endoplasmic reticulum (ER). Cosmc helps C1GALT1 to fold correctly and maintain activity. It also participates in the synthesis of the T antigen, O-glycan, together with C1GALT1. Cosmc is a multifaceted molecule with a wide range of roles and functions. It involves platelet production and the regulation of immune cell function. Besides that, the loss of function of Cosmc also facilitates the development of several diseases, such as inflammation diseases, immune-mediated diseases, and cancer. It suggests that Cosmc is a critical control point in diseases and that it should be regarded as a potential target for oncotherapy. It is essential to fully comprehend Cosmc's roles, as they may provide critical information about its involvement in disease development and pathogenesis. In this review, we summarize the recent progress in understanding the role of Cosmc in normal development and diseases.


Assuntos
Doença , Chaperonas Moleculares , Humanos , Retículo Endoplasmático/metabolismo , Chaperonas Moleculares/metabolismo , Glicosilação
4.
Front Pharmacol ; 13: 965661, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36204225

RESUMO

Dexmedetomidine (DEX) is a highly selective α2 receptor agonist that is routinely used in the clinic for sedation and anesthesia. Recently, an increasing number of studies have shown that DEX has a protective effect against brain injury caused by traumatic brain injury (TBI), subarachnoid hemorrhage (SAH), cerebral ischemia and ischemia-reperfusion (I/R), suggesting its potential as a neuroprotective agent. Here, we summarized the neuroprotective effects of DEX in several models of neurological damage and examined its mechanism based on the current literature. Ultimately, we found that the neuroprotective effect of DEX mainly involved inhibition of inflammatory reactions, reduction of apoptosis and autophagy, and protection of the blood-brain barrier and enhancement of stable cell structures in five way. Therefore, DEX can provide a crucial advantage in neurological recovery for patients with brain injury. The purpose of this study was to further clarify the neuroprotective mechanisms of DEX therefore suggesting its potential in the clinical management of the neurological injuries.

5.
Drug Des Devel Ther ; 16: 3071-3085, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36118165

RESUMO

Background: Dihydromyricetin (DHM) exerts protective effects in various brain diseases. The aim of this research was to investigate the biological role of DHM in cerebral ischemia reperfusion (I/R) injury. Methods: We generated a rat model of cerebral I/R injury by performing middle cerebral artery occlusion/reperfusion (MCAO/R). The neurological score and brain water content of the experimental rats was then evaluated. The infarct volume and extent of apoptosis in brain tissues was then assessed by 2,3,5-triphenyltetrazolium (TTC) and TdT-mediated dUTP nick end labeling (TUNEL) staining. Hippocampal neuronal cells (HT22) were subjected to oxygen-glucose deprivation/reperfusion (OGD/R) and cell counting kit-8 (CCK-8) assays and flow cytometry were performed to detect cell viability and apoptosis. The levels of lipid reactive oxygen species (ROS) and iron were detected and the expression levels of key proteins were assessed by Western blotting. Results: DHM obviously reduced neurological deficits, brain water content, infarct volume and cell apoptosis in the brain tissues of MCAO/R rats. DHM repressed ferroptosis and inhibited the sphingosine kinase 1 (SPHK1)/mammalian target of rapamycin (mTOR) pathway in MCAO/R rats. In addition, DHM promoted cell viability and repressed apoptosis in OGD/R-treated HT22 cells. DHM also suppressed the levels of lipid ROS and intracellular iron in OGD/R-treated HT22 cells. The expression levels of glutathione peroxidase 4 (GPX4) was enhanced while the levels of acyl-CoA synthetase long-chain family member 4 (ACSL4) and phosphatidylethanolamine binding protein 1 (PEBP1) were reduced in OGD/R-treated HT22 cells in the presence of DHM. Moreover, the influence conferred by DHM was abrogated by the overexpression of SPHK1 or treatment with MHY1485 (an activator of mTOR). Conclusion: This research demonstrated that DHM repressed ferroptosis by inhibiting the SPHK1/mTOR signaling pathway, thereby alleviating cerebral I/R injury. Our findings suggest that DHM may be a candidate drug for cerebral I/R injury treatment.


Assuntos
Ferroptose , Traumatismo por Reperfusão , Animais , Coenzima A/metabolismo , Coenzima A/farmacologia , Coenzima A/uso terapêutico , Flavonóis , Glucose/farmacologia , Infarto da Artéria Cerebral Média/tratamento farmacológico , Infarto da Artéria Cerebral Média/metabolismo , Ferro , Ligases/metabolismo , Ligases/farmacologia , Ligases/uso terapêutico , Lipídeos/farmacologia , Mamíferos/metabolismo , Oxigênio/metabolismo , Proteína de Ligação a Fosfatidiletanolamina/metabolismo , Proteína de Ligação a Fosfatidiletanolamina/farmacologia , Proteína de Ligação a Fosfatidiletanolamina/uso terapêutico , Fosfolipídeo Hidroperóxido Glutationa Peroxidase , Fosfotransferases (Aceptor do Grupo Álcool) , Ratos , Espécies Reativas de Oxigênio/metabolismo , Traumatismo por Reperfusão/tratamento farmacológico , Traumatismo por Reperfusão/metabolismo , Transdução de Sinais , Serina-Treonina Quinases TOR/metabolismo , Água
6.
Nat Commun ; 13(1): 5525, 2022 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-36130948

RESUMO

Leaf functional traits are important indicators of plant growth and ecosystem dynamics. Despite a wealth of knowledge about leaf trait relationships, a mechanistic understanding of how biotic and abiotic factors quantitatively influence leaf trait variation and scaling is still incomplete. We propose that leaf water content (LWC) inherently affects other leaf traits, although its role has been largely neglected. Here, we present a modification of a previously validated model based on metabolic theory and use an extensive global leaf trait dataset to test it. Analyses show that mass-based photosynthetic capacity and specific leaf area increase nonlinearly with LWC, as predicted by the model. When the effects of temperature and LWC are controlled, the numerical values for the leaf area-mass scaling exponents converge onto 1.0 across plant functional groups, ecosystem types, and latitudinal zones. The data also indicate that leaf water mass is a better predictor of whole-leaf photosynthesis and leaf area than whole-leaf nitrogen and phosphorus masses. Our findings highlight a comprehensive theory that can quantitatively predict some global patterns from the leaf economics spectrum.


Assuntos
Ecossistema , Água , Nitrogênio/metabolismo , Fósforo/metabolismo , Fotossíntese , Folhas de Planta/metabolismo
7.
New Phytol ; 235(3): 907-922, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35491493

RESUMO

A trait coordination network is constructed through intercorrelations of functional traits, which reflect trait-based adaptive strategies. However, little is known about how these networks change across spatial scales, and what drivers and mechanisms mediate this change. This study bridges that gap by integrating functional traits related to plant carbon gain and water economy into the coordination network of Siberian elm (Ulmus pumila), a eurybiont that survives along a 3800 km environmental gradient from humid forest to arid desert. Our results demonstrated that both stomatal density and stomatal size reached a physiological threshold at which adjustments in these traits were not sufficient to cope with the increased environmental stress. Network analysis further revealed that the mechanism for overcoming this threshold, the stomatal opening ratio, gratio , was represented by the highest values for centrality across different spatial scales, and therefore mediated the changes in the trait coordination network along environmental gradients. The mediating roles manifested as creating the highest maximum theoretical stomatal conductance (gsmax ) but lowest possible gratio for pathogen defense in humid regions, while maintaining the gratio 'sweet spot' (c. 20% in this region) for highest water use efficiency in semihumid regions, and having the lowest gsmax and highest gratio for gas exchange and leaf cooling in arid regions. These results suggested that the stomatal traits related to control of stomatal movement play fundamental roles in balancing gas exchange, leaf cooling, embolism resistance and pathogen defense. These insights will allow more accurate model parameterization for different regions, and therefore better predictions of species' responses to global change.


Assuntos
Estômatos de Plantas , Ulmus , Adaptação Fisiológica , Fenótipo , Folhas de Planta/fisiologia , Estômatos de Plantas/fisiologia , Ulmus/fisiologia , Água/fisiologia
8.
BMC Surg ; 22(1): 127, 2022 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-35366868

RESUMO

BACKGROUND: To explore the application value of free omental wrapping and modified pancreaticojejunostomy in pancreaticoduodenectomy (PD). METHODS: The clinical data of 175 patients who underwent pancreaticoduodenectomy from January 2015 to December 2020 were retrospectively analysed. In total, 86 cases were divided into Group A (omental wrapping and modified pancreaticojejunostomy) and 89 cases were divided into Group B (control group). The incidences of postoperative pancreatic fistula and other complications were compared between the two groups, and univariate and multivariate logistic regression analyses were used to determine the potential risk factors for postoperative pancreatic fistula. Risk factors associated with postoperative overall survival were identified using Cox regression. RESULTS: The incidences of grade B/C pancreatic fistula, bile leakage, delayed bleeding, and reoperation in Group A were lower than those in Group B, and the differences were statistically significant (P < 0.05). Group A had an earlier drainage tube extubation time, earlier return to normal diet time and shorter postoperative hospital stay than the control group (P < 0.05). The levels of C-reactive protein (CRP), interleukin-6 (IL-6), and procalcitonin (PCT) inflammatory factors 1, 3 and 7 days after surgery also showed significant. Univariate and multivariate logistic regression analyses showed that a body mass index (BMI) ≥ 24, pancreatic duct diameter less than 3 mm, no isolation of the greater omental flap and modified pancreaticojejunostomy were independent risk factors for pancreatic fistula (P < 0.05). Cox regression analysis showed that age ≥ 65 years old, body mass index ≥ 24, pancreatic duct diameter less than 3 mm, no isolation of the greater omental flap isolation and modified pancreaticojejunostomy, and malignant postoperative pathology were independent risk factors associated with postoperative overall survival (P < 0.05). CONCLUSIONS: Wrapping and isolating the modified pancreaticojejunostomy with free greater omentum can significantly reduce the incidence of postoperative pancreatic fistula and related complications, inhibit the development of inflammation, and favourably affect prognosis.


Assuntos
Pancreaticoduodenectomia , Pancreaticojejunostomia , Idoso , Humanos , Pancreatectomia/efeitos adversos , Fístula Pancreática/epidemiologia , Fístula Pancreática/etiologia , Pancreaticoduodenectomia/efeitos adversos , Pancreaticojejunostomia/efeitos adversos , Estudos Retrospectivos
9.
Physiol Plant ; 174(1): e13617, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35199364

RESUMO

The classical theory of safety-efficiency trade-off is a common theme in plant sciences. Despite safety and efficiency partly compensating for each other physiologically (namely, there is a compensation effect, CE, among traits from the "whole" organism perspective), they are always mathematically described as a trade-off against one another. However, the compensation effect has never been defined and quantified, let alone its role in the xylem water transport and subsequently photosynthesis. Here, we developed an alternative theory to define the CE as a positive relationship between safety and efficiency, and further define a new trade-off index, SETO, that is expressed as CE multiplied by a trade-off factor (differing from the classical average trade-off value). Then, we tested SETO- and CE-photosynthetic rate relationships across different levels based on a common garden experiment using nine conifers and published data for gymnosperms. The results demonstrated that the compensation effect in xylem functions was the dominant force in facilitating photosynthetic rates from species- to phylum-scale. By integrating the compensation effect into the xylem hydraulic functional strategy, our study clearly indicated that the compensation effect is the evolutionary basis for the coordination of xylem hydraulic and photosynthesis physiology.


Assuntos
Cycadopsida , Traqueófitas , Evolução Biológica , Fotossíntese , Água/fisiologia , Xilema/fisiologia
10.
BMC Neurol ; 21(1): 199, 2021 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-33992070

RESUMO

BACKGROUND: Diseases caused by nontyphoid Salmonella can range from mild, to self-limiting gastroenteritis and severe invasive infection. Relatively rarely, Salmonella may cause severe encephalopathy. CASE PRESENTATION: We report a suspected case of Bickerstaff's brainstem encephalitis caused by Salmonella Dublin. A young man presented with impaired consciousness, ataxia, dysarthria, limb weakness, and restricted eyeball abduction. His clinical symptoms were consistent with Bickerstaff's brainstem encephalitis. CONCLUSIONS: This is the first case report of Bickerstaff's brainstem encephalitis caused by Salmonella Dublin in the literature. After treatment, he recovered and was discharged. Early antibiotic treatment of sepsis may control the disease and avoid serious encephalopathy.


Assuntos
Tronco Encefálico/microbiologia , Encefalite/diagnóstico , Salmonella/isolamento & purificação , Adulto , Ataxia/etiologia , Disartria/etiologia , Humanos , Masculino , Infecções por Salmonella/diagnóstico
11.
J Fungi (Basel) ; 7(4)2021 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-33920042

RESUMO

Acid rain (AR) is an increasingly serious environmental problem that frequently occurs in Southern China with sulfuric acid rain (SAR) as the main type. SAR can negatively affect the growth and physiological properties of trees, but mycorrhizal associations may mitigate such detrimental effects. However, the mechanisms by which arbuscular mycorrhizal fungi control SAR-induced impacts on Torreya grandis plants remain unclear. A pot experiment was conducted on T. grandis seedlings, an economically important tree species in Southern China, in which inoculated and non-inoculated T. grandis seedlings were subjected to three simulated SAR regimes (pH of 5.6, 4.0, and 2.5, respectively) to examine the effects on the growth, osmotic regulation, and nutrient absorption of these seedlings. The results show that, although SAR had no effect on the accumulation of biomass, it significantly decreased the concentrations of proline and soluble protein, shoot Zn2+, P, K+, and Ca2+ concentrations, and the Fe2+ and Mn2+ concentrations of shoots and roots. Mycorrhizal inoculation, especially with Rhizophagus irregularis, significantly increased total biomass, proline concentration, and the Zn2+, P, and K+ concentrations in the shoots of T. grandis under lower pH conditions. Moreover, our findings suggest that the combination of root colonization, acid tolerance, and the concentrations of shoot-P, shoot-Zn2+, and root-Fe2+ of T. grandis jointly conferred mycorrhizal benefits on the plants under SAR conditions. Given the enhancement of the nutritional quality of T. grandis owing to mycorrhizal associations, inoculation with R. irregularis may be preferable for the culturing and management of these plants under acidic conditions.

12.
Medicine (Baltimore) ; 100(11): e25188, 2021 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-33726009

RESUMO

RATIONALE: The HLH-94 protocol is a standard induction treatment for hemophagocytic lymphohistiocytosis. However, about 30% of patients may not respond. Ruxolitinib has been clinically proven to be an effective treatment for hemophagocytic lymphohistiocytosis (HLH). PATIENT CONCERNS: A previously healthy 14-year-old girl presented to the local hospital with a 4-day history of persistent fever and sore throat. DIAGNOSIS: Clinical and laboratory tests revealed fever >38.5°C, hepatosplenomegaly, pancytopenia, hypertriglyceridemia, hypofibrinogenemia, hyperferritinemia, and an elevated interleukin-2 receptor level. INTERVENTION: This patient was treated with ruxolitinib and the HLH-94 protocol. OUTCOMES: The patient's clinical and some laboratory indices improved. Unfortunately, vital signs such as respiratory function and consciousness did not improve. LESSONS: This case report highlights the effect of using ruxolitinib in conjunction with the HLH-94 protocol. However, safety evaluation of this regimen was not performed because critically ill patient died too fast.


Assuntos
Infecções por Vírus Epstein-Barr/tratamento farmacológico , Herpesvirus Humano 4 , Linfo-Histiocitose Hemofagocítica/tratamento farmacológico , Pirazóis/administração & dosagem , Adolescente , Protocolos Clínicos , Dexametasona/administração & dosagem , Doxorrubicina/administração & dosagem , Doxorrubicina/análogos & derivados , Quimioterapia Combinada , Infecções por Vírus Epstein-Barr/complicações , Etoposídeo/administração & dosagem , Evolução Fatal , Feminino , Humanos , Quimioterapia de Indução , Unidades de Terapia Intensiva , Linfo-Histiocitose Hemofagocítica/virologia , Metilprednisolona/administração & dosagem , Nitrilas , Polietilenoglicóis/administração & dosagem , Pirimidinas , Resultado do Tratamento
13.
J Mater Chem B ; 8(18): 4080-4092, 2020 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-32239064

RESUMO

Due to the untargeted release of chemical drugs, the efficacy of chemotherapy is often compromised along with serious side effects on patients. Recently, the development of targeted delivery systems using nanomaterials as carriers has provided more alternatives for chemical drug transportation. In this study, we developed a novel targeted nanocomplex of GOQD-ICG-DOX@RBCM-FA NPs (GID@RF NPs). First, PEG modified graphene oxide quantum dots (GOQDs) were used to co-load the photosensitizer of indocyanine green (ICG) and DOX, to form GOQD-ICG-DOX NPs (GID NPs). Then, the red blood cell membrane (RBCM) was applied for GID NP camouflage to avoid immune clearance. Finally, folic acid was used to endow the targeting ability of GID@RF NPs. MTT assay showed that the survival rate of HeLa cells reduced by 71% after treatment with GID@RF NPs and laser irradiation. Meanwhile, membrane camouflage significantly prolonged the blood circulation time and enhanced the immune evading ability of GID NPs. Moreover, the drug accumulation at tumor sites was significantly improved through the strong interaction between FA and FA receptor highly expressed on the tumor cells. In vivo assay demonstrated the strongest tumor growth inhibition ability of the combinational chemo/photothermal therapy. H&E analysis indicated no significant abnormalities in the major organs of mice undergoing GID@RF NPs treatment. The level of blood and biochemical parameters remained stable as compared to the control. In summary, this combinational therapy system provides a safe, rapid and effective alternative for the treatment of cervical cancer in the future.


Assuntos
Antibióticos Antineoplásicos/farmacologia , Materiais Biomiméticos/química , Doxorrubicina/farmacologia , Membrana Eritrocítica/química , Nanopartículas/química , Fotoquimioterapia , Fármacos Fotossensibilizantes/farmacologia , Neoplasias do Colo do Útero/tratamento farmacológico , Animais , Antibióticos Antineoplásicos/química , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Doxorrubicina/química , Feminino , Células HeLa , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Neoplasias Experimentais/diagnóstico por imagem , Neoplasias Experimentais/tratamento farmacológico , Imagem Óptica , Tamanho da Partícula , Fármacos Fotossensibilizantes/química , Propriedades de Superfície , Neoplasias do Colo do Útero/diagnóstico por imagem
14.
Sci Rep ; 10(1): 5396, 2020 03 25.
Artigo em Inglês | MEDLINE | ID: mdl-32214162

RESUMO

As the second largest carbon flux in terrestrial ecosystems, the soil CO2 flux is closely related to the atmospheric CO2 concentration. The soil CO2 flux is the sum of biotic respiration and abiotic geochemical CO2 exchange; however, little is known about abiotic CO2 fluxes in arid areas. To investigate the relative contribution of abiotic and biotic soil CO2 fluxes over a diurnal course, the abiotic CO2 flux was distinguished by autoclaving sterilization in both saline and alkaline soils at an arid site in northwestern China. The results demonstrated that: (1) Over the diurnal course, the abiotic CO2 was a significant component of the soil CO2 flux in both saline and alkaline soil, which accounted for more than 56% of the diurnal soil CO2 flux. (2) There was a dramatic difference in the temperature response between biotic and abiotic CO2 fluxes: the response curves of biotic respiration were exponential in the saline soil and quadratic in the alkaline soil, while the abiotic CO2 flux was linearly correlated with soil temperature. They were of similar magnitude but with opposite signs: resulting in almost neutral carbon emissions on daily average. (3) Due to this covering up effect of the abiotic CO2 flux, biotic respiration was severely underestimated (directly measured soil CO2 flux was only one-seventh of the biotic CO2 flux in saline soil, and even an order of magnitude lower in alkaline soil). In addition, the soil CO2 flux masked the temperature-inhibition of biotic respiration in the alkaline soil, and veiled the differences in soil biological respiration between the saline and alkaline soils. Hence, the soil CO2 flux may not be an ideal representative of soil respiration in arid soil. Our study calls for a reappraisal of the definition of the soil CO2 flux and its temperature dependence in arid or saline/alkaline land. Further investigations of abiotic CO2 fluxes are needed to improve our understanding of arid land responses to global warming and to assist in identifying the underlying abiotic mechanisms.

15.
Biomed Pharmacother ; 99: 402-410, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29367109

RESUMO

Colorectal cancer (CRC) is one of the major causes of cancer deaths worldwide. Wild-type p53-induced protein 1 (WIP1) is overexpressed in multiple human cancers and acted as an oncogene. This study was aimed to investigate the effect of WIP1 in colorectal cancer growth and analyzed underlying mechanisms. Herein, we determined WIP1 expression in CRC tissues and cell lines, as well as evaluated its detailed function in CRC cell proliferation. Several factors have been reported to mediate WIP1 effects; herein, we examined the involvement of mTOR and p21 in WIP1 regulation of CRC cell proliferation. Moreover, NF-κB has been regarded as a positive transcriptional regulator of WIP1 to activate its expression. NF-κB knockdown suppressed CRC cell proliferation, which could be reversed by WIP1 overexpression, through p21 and mTOR. Further, we examined the binding of NF-κB to the promoter region of WIP1. In CRC tissues, NF-κB expression was significantly up-regulated, and positively correlated with WIP1 expression, suggesting that inhibiting NF-κB expression to attenuate its activating effect on WIP1 expression presented a promising strategy of controlling excess proliferation of CRC cell. In summary, WIP1 promotes CRC proliferation through p21 and mTOR, both downstream targets of p53; NF-κB served as a positive transcriptional regulator of WIP1 to activate its expression and affect its function in CRC cells. Our finding provided a novel strategy for treatment for CRC.


Assuntos
Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , NF-kappa B/metabolismo , Proteína Fosfatase 2C/metabolismo , Transdução de Sinais , Serina-Treonina Quinases TOR/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/genética , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Feminino , Regulação Neoplásica da Expressão Gênica , Técnicas de Silenciamento de Genes , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Prognóstico , Regiões Promotoras Genéticas/genética , Modelos de Riscos Proporcionais , Ligação Proteica , Proteína Fosfatase 2C/genética , Regulação para Cima/genética
16.
AoB Plants ; 82016.
Artigo em Inglês | MEDLINE | ID: mdl-27073036

RESUMO

The response of plants to drought is controlled by the interaction between physiological regulation and morphological adjustment. Although recent studies have highlighted the long-term morphological acclimatization of plants to drought, there is still debate on how plant biomass allocation patterns respond to drought. In this study, we performed a greenhouse experiment with first-year seedlings of a desert shrub in control, drought and re-water treatments, to examine their physiological and morphological traits during drought and subsequent recovery. We found that (i) biomass was preferentially allocated to roots along a fixed allometric trajectory throughout the first year of development, irrespective of the variation in water availability; and (ii) this fixed biomass allocation pattern benefited the post-drought recovery. These results suggest that, in a stressful environment, natural selection has favoured a fixed biomass allocation pattern rather than plastic responses to environmental variation. The fixed 'preferential allocation to root' biomass suggests that roots may play a critical role in determining the fate of this desert shrub during prolonged drought. As the major organ for resource acquisition and storage, how the root system functions during drought requires further investigation.

17.
Sci Rep ; 5: 12174, 2015 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-26190745

RESUMO

Species competitive abilities and their distributions are closely related to functional traits such as biomass allocation patterns. When we consider how nutrient supply affects competitive abilities, quantifying the apparent and true plasticity in functional traits is important because the allometric relationships among traits are universal in plants. We propose to integrate the notion of allometry and the classical reaction norm into a composite theoretical framework that quantifies the apparent and true plasticity. Combining the framework with a meta-analysis, a series of field surveys and a competition experiment, we aimed to determine the causes of the dune/interdune distribution patterns of two Haloxylon species in the Gurbantonggut Desert. We found that (1) the biomass allocation patterns of both Haloxylon species in responses to environmental conditions were apparent rather than true plasticity and (2) the allometric allocation patterns affected the plants' competition for soil nutrient supply. A key implication of our results is that the apparent plasticity in functional traits of plants determines their response to environmental change. Without identifying the apparent and true plasticity, we would substantially overestimate the magnitude, duration and even the direction of plant responses in functional traits to climate change.


Assuntos
Clima Desértico , Plantas , Dinâmica Populacional , Característica Quantitativa Herdável , Biomassa , Fenótipo , Raízes de Plantas , Estações do Ano , Plântula , Solo/química
18.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 39(4): 416-22, 2014 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-24820283

RESUMO

Comprehensive evaluation methods are generally used to assess the population data. When we need to estimate the sample data in special situations, the impacts brought by the sampling error should be considered. Due to lack of the accurate measurement for the sensitivity and stability in the comprehensive evaluation methods, sampling errors usually cannot be estimated in the sampling research. Monte Carlo simulation was used in this article to solve the probability of the ordering results, and the matlab programs were presented. Based on the simulated results, we change the conventional "absolute conclusion" of comprehensive evaluation methods to "probability results" for the sample data, and put forward a new sorting and ranking method for the results of comprehensive evaluation.


Assuntos
Pesquisa Biomédica , Método de Monte Carlo
19.
PLoS One ; 7(7): e41502, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22911802

RESUMO

In resource-poor environments, adjustment in plant biomass allocation implies a complex interplay between environmental signals and plant development rather than a delay in plant development alone. To understand how environmental factors influence biomass allocation or the developing phenotype, it is necessary to distinguish the biomass allocations resulting from environmental gradients or ontogenetic drift. Here, we compared the development trajectories of cotton plants (Gossypium herbaceum L.), which were grown in two contrasting soil textures during a 60-d period. Those results distinguished the biomass allocation pattern resulting from ontogenetic drift and the response to soil texture. The soil texture significantly changed the biomass allocation to leaves and roots, but not to stems. Soil texture also significantly changed the development trajectories of leaf and root traits, but did not change the scaling relationship between basal stem diameter and plant height. Results of nested ANOVAs of consecutive plant-size categories in both soil textures showed that soil gradients explained an average of 63.64-70.49% of the variation of biomass allocation to leaves and roots. Ontogenetic drift explained 77.47% of the variation in biomass allocation to stems. The results suggested that the environmental factors governed the biomass allocation to roots and leaves, and ontogenetic drift governed the biomass allocation to stems. The results demonstrated that biomass allocation to metabolically active organs (e.g., roots and leaves) was mainly governed by environmental factors, and that biomass allocation to metabolically non-active organs (e.g., stems) was mainly governed by ontogenetic drift. We concluded that differentiating the causes of development trajectories of plant traits was important to the understanding of plant response to environmental gradients.


Assuntos
Aclimatação/fisiologia , Biomassa , Gossypium/crescimento & desenvolvimento , Gossypium/fisiologia , Desenvolvimento Vegetal/genética , Solo/química , Análise de Variância , Tamanho Corporal , Gossypium/anatomia & histologia , Tamanho da Partícula , Folhas de Planta/anatomia & histologia , Folhas de Planta/crescimento & desenvolvimento , Raízes de Plantas/anatomia & histologia , Raízes de Plantas/crescimento & desenvolvimento , Caules de Planta/anatomia & histologia , Caules de Planta/crescimento & desenvolvimento , Característica Quantitativa Herdável
20.
Acta Crystallogr Sect E Struct Rep Online ; 66(Pt 4): m368, 2010 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-21580481

RESUMO

The title centrosymmetric dinuclear Ni(II) complex, [Ni(C(14)H(8)O(4)S)(C(3)H(7)NO)](n), was prepared via reaction of Ni(NO(3))(2)·6H(2)O and thio-salicylic acid, with H(2)O and dimethyl-formamide (DMF) as the mixed solvent. The central Ni(II) ion is five-coordinated by five O atoms from DMF and from the carboxyl-ate groups of the organic ligand. The symmetry-related coordination polyhedra inter-link into centrosymmetric dimeric units and these, in turn, are linked into infinite chains propagating parallel to [100].

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