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1.
J Environ Manage ; 354: 120318, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38387347

RESUMO

In desert wetlands, the decline in ground water table results in desertification, triggering soil carbon and nutrient loss. However, the impacts of desertification on soil dissolved organic carbon (DOC) properties which determine the turnover of soil carbon and nutrients are unclear. Here, the desertification gradient was represented by the distance from the wetland center (0∼240 m) traversing reed marshes, desert shrubs and bare sandy land in the Hongjian Nur Basin, north China. Soil DOC properties were determined by ultraviolet and fluorescence spectroscopy coupled with parallel factor analysis (PARAFAC). Results showed that soil DOC content decreased significantly from 107.23 mg kg-1 to 8.44 mg kg-1 by desertification (p < 0.05). However, the proportion of DOC to soil organic carbon (SOC) was gradually significantly increased. According to spectral parameters, microbial-derived DOC decreased from 0 to 120 m (reed marshes to desert shrubs) but increased from 120 to 240 m (desert shrubs to bare sandy lands), with a reverse hump-shaped distribution pattern. The molecular weight and aromaticity of DOC increased from 0 to 120 m but decreased from 120 to 240 m, with a hump-shaped distribution pattern. For the DOC composition, although the relative abundances of humic-acid components remained stable (p > 0.05), they were ultimately decreased by serious desertification and the amino acids became the dominant component. A similar change pattern was also found for humification index. Additionally, MBC and C:N were the two most important variables in determining the content and spectral properties, respectively. Together, these findings relationships between the soil DOC properties and desertification degree, especially the increase in DOC proportion and the decrease in humification degree, which may reduce soil C stabilization in the Hongjian Nur Basin.


Assuntos
Areia , Solo , Solo/química , Áreas Alagadas , Matéria Orgânica Dissolvida , Carbono/análise , Conservação dos Recursos Naturais , China
2.
BMC Cardiovasc Disord ; 23(1): 218, 2023 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-37118657

RESUMO

BACKGROUND: The cardiac magnetic resonance tissue tracking (CMR-TT) technique was used to obtain left atrial strain and strain rate in patients with myocardial infarction (MI) and to evaluate the utility of this technique in the quantitative assessment of myocardial infarction for distinguishing acute from chronic myocardial infarction. METHODS: We retrospectively analyzed 36 consecutive patients with acute myocardial infarction (AMI) and 29 patients with chronic myocardial infarction (CMI) who underwent CMR and 30 controls. Left atrial (LA) and ventricular functions were quantified by volumetric, and CMR-TT derived strain analysis from long and short left ventricular view cines. Receiver Operating Characteristics (ROC) analysis was used to determine the diagnostic accuracy of CMR-TT strain parameters for discriminating between acute and chronic myocardial infarction. RESULTS: AMI and CMI participants had impaired LA reservoir function, conduit function and LA booster pump dysfunction compared to the controls. LA strain was more sensitive than LV global strain for the assessment of the MI stage. Peak late-negative SR yielded the best areas under the ROC curve (AUC) of 0.879, showing differentiation between acute and chronic myocardial infarction of all the LA strain parameters obtained. The highest significant differences between chronic myocardial infarction and normal myocardium were also found in the LV strain (p < 0.001) and LA functional parameters (p < 0.001), but there was no difference between AMI and normals. CONCLUSIONS: CMR-TT-derived LA strain is a potential and robust tool in demonstrating impaired LA mechanics and quantifying LA dynamics, which have high sensitivity and specificity in the differential diagnosis of acute versus chronic myocardial infarction. Their use is thus worth popularizing in clinical application.


Assuntos
Fibrilação Atrial , Infarto do Miocárdio , Humanos , Estudos Retrospectivos , Imagem Cinética por Ressonância Magnética/métodos , Função do Átrio Esquerdo , Infarto do Miocárdio/diagnóstico por imagem , Função Ventricular Esquerda
3.
Geriatr Nurs ; 49: 157-163, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36543041

RESUMO

This study aimed to compare the diagnostic values of SARC-F (strength, assistance with walking, rising from a chair, climbing stairs, and falls), SARC-Calf (SARC-F combined with calf circumference), CC (calf circumference), and the Yubi-wakka (finger-ring) test for screening for sarcopenia in community-dwelling older adults. The Asian Working Group for Sarcopenia (AWGS) 2019 criteria were used as a standard reference. A total of 209 participants were enrolled, and 40.7% were identified as sarcopenia. The sensitivity, specificity, and AUC were respectively 54.1%, 70.2%, and 0.687 for SARC-F; 76.5%, 73.4% and 0.832 for SARC-calf, 86.7%, 82.4%, and 0.906 for CC in men, and 85.5%, 63.3%, and 0.877 for CC in women. Relative to the "bigger," a significant association between sarcopenia and the Yubi-wakka test ("just fits" OR: 4.1, 95% CI: 1.57-10.98; "small" OR: 27.5, 95% CI: 10.14-74.55) was observed. The overall accuracy of CC was better than SARC-Calf for sarcopenia screening.


Assuntos
Sarcopenia , Masculino , Humanos , Feminino , Idoso , Sarcopenia/diagnóstico , Vida Independente , Perna (Membro) , Caminhada , Avaliação Geriátrica/métodos , Inquéritos e Questionários
4.
Eur Radiol ; 32(11): 7824-7832, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35475935

RESUMO

OBJECTIVES: We aimed to investigate the correlation between an overall cerebral small vessel disease (CSVD) burden and outcomes after endovascular treatment (EVT) for patients with acute ischemic stroke (AIS) due to large vessel occlusion (LVO). METHODS: In a multicenter registry study, we enrolled patients with EVT for anterior-circulation LVO-stroke. In 3.0-T MR imaging, we assessed 4 CSVD imaging markers, lacunes, white matter hyperintensities, cerebral microbleeds, and enlarged perivascular spaces, each assigned a score of 0 or 1 and summed up to an overall CSVD burden score of 0-4. We dichotomized the overall CSVD severity as none to mild (score 0-2) and moderate to severe (3-4). Primary outcome was 90-day functional dependence or death (modified Rankin Scale (mRS) 3-6). Secondary outcomes included increase in NIH Stroke Scale ≥ 4 within 24 h (early neurological deterioration (END)) and within 7 days, symptomatic intracranial hemorrhage, 90-day mRS 2-6, and 90-day mortality. RESULTS: Among 311 patients (63.0% male; mean age 65.1 ± 12.7 years), 260 (83.6%) had none-to-mild and 51 (16.4%) had moderate-to-severe overall CSVD burden. Moderate-to-severe CSVD burden was not significantly associated with the primary outcome (47.1% versus 45.4%; p > 0.05 in univariate and multivariate logistic regression), or the secondary outcomes except for a higher risk of END (11.8% versus 3.1%; p < 0.05 in multivariate analyses). Sensitivity analyses with 0-1 versus 2-4 of the CSVD burden score, and the score as an ordinal variable, showed similar results. CONCLUSIONS: An overall moderate-to-severe CSVD burden was not associated with 90-day functional dependence or death, after EVT for anterior-circulation LVO. TRIAL REGISTRATION: ChiCTR1900022154 KEY POINTS: • Moderate-to-severe cerebral small vessel disease burden on MRI should not be an exclusion indicator in determining the eligibility of an acute ischemic stroke patient for endovascular treatment.


Assuntos
Isquemia Encefálica , Doenças de Pequenos Vasos Cerebrais , AVC Isquêmico , Acidente Vascular Cerebral , Humanos , Masculino , Pessoa de Meia-Idade , Idoso , Feminino , Doenças de Pequenos Vasos Cerebrais/diagnóstico por imagem , Trombectomia , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/complicações , Efeitos Psicossociais da Doença , Isquemia Encefálica/diagnóstico por imagem , Isquemia Encefálica/cirurgia , Isquemia Encefálica/complicações
5.
Stroke ; 52(4): 1473-1477, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33657858

RESUMO

BACKGROUND AND PURPOSE: Intraluminal thrombus (ILT) is an emerging imaging marker in acute ischemic stroke. We aimed to investigate the association of ILT with outcomes of acute large vessel occlusion (LVO) patients receiving endovascular treatment. METHODS: Acute LVO stroke patients who underwent endovascular treatment within 24 hours, in a prospective, nationwide registry were enrolled. Pretreatment digital subtraction angiography was reviewed for the presence of ILT. The primary outcome was 90-day functional dependence (modified Rankin Scale scores, 3-6). Secondary outcomes included 24-hour LVO, 90-day death, and symptomatic intracranial hemorrhage. RESULTS: Among 711 patients enrolled, 75 (10.5%) with ILT were less likely to have 90-day functional dependence compared with those without ILT (adjusted odds ratio, 0.53 [95% CI, 0.31-0.90]; P=0.021). The same trend was found among those with successful reperfusion (modified Thrombolysis in Cerebral Infarction 2b-3; P=0.008) but not in those without successful reperfusion (P=0.107). Presence of ILT was also independently associated with a lower rate of 24-hour LVO (adjusted odds ratio 0.34 [95% CI, 0.13-0.89]; P=0.028). However, those with or without ILT had similar risks of symptomatic intracranial hemorrhage and 90-day death. CONCLUSIONS: Among acute LVO patients receiving endovascular treatment, pretreatment ILT-positive patients may have a better 90-day functional outcome (versus ILT-negative) but similar risk of death and symptomatic intracranial hemorrhage. The possibly favorable effect of ILT patients remained in those with successful reperfusion. Registration: URL: http://www.chictr.org.cn; Unique identifier: ChiCTR1900022154.


Assuntos
Procedimentos Endovasculares/métodos , AVC Isquêmico/patologia , AVC Isquêmico/cirurgia , Trombose/patologia , Idoso , Angiografia Digital , Feminino , Humanos , AVC Isquêmico/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Trombose/diagnóstico por imagem , Trombose/cirurgia , Resultado do Tratamento
6.
Stroke ; 51(9): 2742-2751, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32811382

RESUMO

BACKGROUND AND PURPOSE: We aimed to evaluate the impact of cortical microinfarcts (CMIs) on functional outcome after endovascular treatment in patients with acute ischemic stroke. METHODS: In a multicenter registration study for RESCUE-RE (a registration study for Critical Care of Acute Ischemic Stroke After Recanalization), eligible patients with large vessel occlusion stroke receiving endovascular treatment, who had undergone 3T magnetic resonance imaging on admission or within 24 hours after endovascular treatment were analyzed. We evaluated the presence and numbers of CMIs with assessment of axial T1, T2-weighted images, and fluid-attenuated inversion recovery images. The primary outcome was functional dependence or death defined as modified Rankin Scale scores of 3 to 6 at 90 days. Secondary outcomes included early neurological improvement, any intracranial hemorrhage, symptomatic intracranial hemorrhage, and mortality. We investigated the independent associations of CMIs with the outcomes using multivariable logistic regression in overall patients and in subgroups. RESULTS: Among 414 patients (enrolled from July 2018 to May 2019) included in the analyses, 96 (23.2%) patients had at least one CMI (maximum 6). Patients with CMI(s) were more likely to be functionally dependent or dead at 90 days, compared with those without (55.2% versus 37.4%; P<0.01). In multivariable logistic regression analyses, presence of CMI(s) (adjusted odds ratio, 1.78 [95% CI, 1.04-3.07]; P=0.04) and multiple CMIs (CMIs ≥2; adjusted odds ratio, 7.41 [95% CI, 2.48-22.17]; P<0.001) were independently, significantly associated with the primary outcome. There was no significant difference between subgroups in the associations between CMI presence and the primary outcome. CONCLUSIONS: Acute large vessel occlusion stroke patients receiving endovascular treatment with CMI(s) were more likely to have a poor functional outcome at 90 days, independent of patients' characteristics. Such associations may be dose-dependent. Registration: URL: http://www.chictr.org.cn; Unique identifier: ChiCTR1900022154.


Assuntos
Isquemia Encefálica/complicações , Isquemia Encefálica/cirurgia , Córtex Cerebral , Infarto Cerebral/complicações , Procedimentos Endovasculares/métodos , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Arteriopatias Oclusivas/complicações , Arteriopatias Oclusivas/cirurgia , Isquemia Encefálica/diagnóstico por imagem , Córtex Cerebral/diagnóstico por imagem , Infarto Cerebral/diagnóstico por imagem , Infarto Cerebral/mortalidade , Feminino , Humanos , Hemorragias Intracranianas/etiologia , Angiografia por Ressonância Magnética , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Sistema de Registros , Acidente Vascular Cerebral/diagnóstico por imagem , Resultado do Tratamento
7.
Hu Li Za Zhi ; 67(2): 33-44, 2020 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-32281081

RESUMO

BACKGROUND: Middle-aged and older individuals suffer from skeletal muscle loss due to aging, increasing the risk of sarcopenia. Muscular dystrophy reduces lower-extremity muscle endurance. The annual incidence of falls in the community is about 30-40%. Falls contribute to disability and fractures, affect quality of life, reduce mental health, and, in severe cases, result in death. Therefore, preventing lower limb muscle weakness in middle-aged and older individuals should be taken seriously. PURPOSE: The purpose of this study was to promote community health with a focus on older, community-dwelling individuals. The effects of a lower-extremity exercise intervention on middle-aged and older individuals in terms of improving functional fitness, physiological indexes, exercise self-efficacy, sleep quality, and mental health were explored. METHODS: This study used convenience sampling to recruit community residents over 55 years old as participants, with 50 participants assigned to the control group and to the experimental group, respectively. The experimental group participated in a 50-min lower extremity exercise intervention three times a week for 12 weeks. Differences in functional fitness, basic physiological index, exercise self-efficacy, sleep quality, and mental health variables between the two groups were assessed at the conclusion of the intervention. RESULTS: The lower-extremity muscle exercise program significantly improved functional fitness, physiological indexes, exercise self-efficacy, sleep quality, and overall mental health status in the experimental group, as compared to the control group (p < .05). CONCLUSIONS / IMPLICATIONS FOR PRACTICE: It is recommended that the concept and application of lower extremity movement intervention should be popularized among middle-aged and older individuals to promote physical and mental health, prevent the decline and loss of lower extremity muscle strength, and help realize healthy aging goals.


Assuntos
Exercício Físico/fisiologia , Exercício Físico/psicologia , Promoção da Saúde/métodos , Extremidade Inferior/fisiologia , Idoso , Humanos , Vida Independente , Saúde Mental/estatística & dados numéricos , Pessoa de Meia-Idade , Aptidão Física/fisiologia , Avaliação de Programas e Projetos de Saúde , Autoeficácia , Sono/fisiologia
8.
J Am Chem Soc ; 141(34): 13654-13663, 2019 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-31398288

RESUMO

Postsynthetic metalation (PSM) has been employed as a robust method for the postsynthetic modification of metal-organic frameworks (MOFs). However, the lack of relevant information that can be obtained for the postsynthetically introduced metallic ions has hindered the development of PSM applications. Thanks to the advancement in single-crystal X-ray diffraction (SCXRD) technology, there have been a few recent examples in which successful postsynthetic introduction of single metal ions into MOFs occurred at the defined chelating sites. These works have provided useful explanations about the complicated host-guest chemistry involved in PSMs. On the other hand, there are only limited examples with crystallographic snapshots of the postsynthetic installation of metal clusters into the pores of MOFs using an ordinary SCXRD due to the loss of crystallinity of parent matrix during the PSM process. Herein, by the careful selection of starting materials and controlling the reaction conditions, we report the first crystallographic visualization of metal clusters inserted into Zr-based MOFs via PSM. The structural advantages of the parent Zr-MOF, which are inherited from the stable Zr6 cluster and triazole-containing dicarboxylate ligand, ensure both the preservation of high crystallinity and the presence of flexible coordination sites for PSM. Furthermore, PSM of metal clusters in a MOF pore space enhances stability of the final samples while also imparting the functionality of a successful catalyst toward ethylene dimerization reaction. The related construction ideas and structural information detailed in this work can help lay the foundation for further advancements using the postmodification of MOFs as well as open new doors for the utilization of SCXRD technology in the field of MOFs.

9.
Hu Li Za Zhi ; 66(1): 21-26, 2019 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-30648242

RESUMO

Oral health impacts the physical and psychological comfort and the quality of life of clients in long-term care. The programs to prevent or delay disability care advocated under Taiwan's Long-Term Care Plan 2.0 address oral health care, highlighting the importance of oral health care for clients in long-term care. This article discusses three concepts of oral health care for clients who are in long-term care. These include: the relationship between oral conditions and general health, oral care and dysphagia, and oral health and hydration. In addition, oral health care strategies for long-term care facilities are discussed. It is hoped that this article will encourage long-term care practitioners to pay close attention to the issue of oral health and to implement appropriate oral health care for their long-term-care clients.


Assuntos
Assistência Odontológica , Transtornos de Deglutição/epidemiologia , Humanos , Assistência de Longa Duração , Saúde Bucal , Qualidade de Vida , Taiwan/epidemiologia
10.
Zhongguo Dang Dai Er Ke Za Zhi ; 21(10): 972-976, 2019 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-31642429

RESUMO

OBJECTIVE: To study the types and characteristics of TUBB1 mutation in children with congenital hypothyroidism (CH) and thyroid dysgenesis (TD) in Shandong, China. METHODS: Mutations of the whole coding region of the TUBB1 gene were analyzed for 289 children with CH and TD in Shandong. Whole-genome DNA was extracted from peripheral blood leukocytes. PCR multiplication was performed for the whole coding region of the TUBB1 gene. Sanger sequencing was performed for the PCR products, and a biological information analysis was performed. RESULTS: Among the 289 children with CH and TD, 4 (1.4%) were found to have a c.952C>T(p.R318W) heterozygous mutation in the TUBB1 gene, resulting in the change of tryptophan into arginine at codon 318 of TUBB1 protein. This mutation was evaluated as "potentially pathogenic" based on the classification criteria and guidelines for genetic variation by American College of Medical Genetics and Genomics. CONCLUSIONS: A novel mutation is detected in the exon of the TUBB1 gene in children with CH and TD in Shandong, suggesting that the TUBB1 gene may be a candidate pathogenic gene for CH children with TD.


Assuntos
Hipotireoidismo Congênito , Disgenesia da Tireoide , Tubulina (Proteína)/genética , Criança , China , Hipotireoidismo Congênito/genética , Análise Mutacional de DNA , Humanos , Mutação , Disgenesia da Tireoide/genética
11.
J Neuroinflammation ; 15(1): 4, 2018 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-29304864

RESUMO

BACKGROUND: Cognitive impairment is one of common complications of acute respiratory distress syndrome (ARDS). Increasing evidence suggests that interleukin-1 beta (IL-1ß) plays a role in inducing neuronal apoptosis in cognitive dysfunction. The lung protective ventilatory strategies, which serve to reduce pulmonary morbidity for ARDS patients, almost always lead to hypercapnia. Some studies have reported that hypercapnia contributes to the risk of cognitive impairment and IL-1ß secretion outside the central nervous system (CNS). However, the underlying mechanism of hypercapnia aggravating cognitive impairment under hypoxia has remained uncertain. This study was aimed to explore whether hypercapnia would partake in increasing IL-1ß secretion via activating the NLRP3 (NLR family, pyrin domain-containing 3) inflammasome in the hypoxic CNS and in aggravating cognitive impairment. METHODS: The Sprague-Dawley (SD) rats that underwent hypercapnia/hypoxemia were used for assessment of NLRP3, caspase-1, IL-1ß, Bcl-2, Bax, and caspase-3 expression by Western blotting or double immunofluorescence, and the model was also used for Morris water maze test. In addition, Z-YVAD-FMK, a caspase-1 inhibitor, was used to treat BV-2 microglia to determine whether activation of NLRP3 inflammasome was required for the enhancing effect of hypercapnia on expressing IL-1ß by Western blotting or double immunofluorescence. The interaction effects were analyzed by factorial ANOVA. Simple effects analyses were performed when an interaction was observed. RESULTS: There were interaction effects on cognitive impairment, apoptosis of hippocampal neurons, activation of NLRP3 inflammasome, and upregulation of IL-1ß between hypercapnia treatment and hypoxia treatment. Hypercapnia + hypoxia treatment caused more serious damage to the learning and memory of rats than those subjected to hypoxia treatment alone. Expression levels of Bcl-2 were reduced, while that of Bax and caspase-3 were increased by hypercapnia in hypoxic hippocampus. Hypercapnia markedly increased the expression of NLRP3, caspase-1, and IL-1ß in hypoxia-activated microglia both in vivo and in vitro. Pharmacological inhibition of NLRP3 inflammasome activation and release of IL-1ß might ameliorate apoptosis of neurons. CONCLUSIONS: The present results suggest that hypercapnia-induced IL-1ß overproduction via activating the NLRP3 inflammasome by hypoxia-activated microglia may augment neuroinflammation, increase neuronal cell death, and contribute to the pathogenesis of cognitive impairments.


Assuntos
Disfunção Cognitiva/metabolismo , Hipercapnia/metabolismo , Hipóxia/metabolismo , Interleucina-1beta/biossíntese , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Fatores Etários , Animais , Disfunção Cognitiva/psicologia , Hipercapnia/psicologia , Hipóxia/psicologia , Masculino , Aprendizagem em Labirinto/fisiologia , Ratos , Ratos Sprague-Dawley
12.
BMC Neurosci ; 18(1): 32, 2017 03 14.
Artigo em Inglês | MEDLINE | ID: mdl-28288585

RESUMO

BACKGROUND: Ischemic stroke is a major disease that threatens human health in ageing population. Increasing evidence has shown that neuroinflammatory mediators play crucial roles in the pathophysiology of cerebral ischemia injury. Notch signaling is recognized as the cell fate signaling but recent evidence indicates that it may be involved in the inflammatory response in activated microglia in cerebral ischemia. Previous report in our group demonstrated hypertonic saline (HS) could reduce the release of interleukin-1 beta and tumor necrosis factor-alpha in activated microglia, but the underlying molecular and cellular mechanisms have remained uncertain. This study was aimed to explore whether HS would partake in regulating production of proinflammatory mediators through Notch signaling. RESULTS: HS markedly attenuated the expression of Notch-1, NICD, RBP-JK and Hes-1 in activated microglia both in vivo and in vitro. Remarkably, HS also reduced the expression of iNOS in vivo, while the in vitro levels of inflammatory mediators Phos-NF-κB, iNOS and ROS were reduced by HS as well. CONCLUSION: Our results suggest that HS may suppress of inflammatory mediators following ischemia/hypoxic through the Notch signaling which operates synergistically with NF-κB pathway in activated microglia. Our study has provided the morphological and biochemical evidence that HS can attenuate inflammation reaction and can be neuroprotective in cerebral ischemia, thus supporting the use of hypertonic saline by clinicians in patients with an ischemia stroke.


Assuntos
Isquemia Encefálica/tratamento farmacológico , Hipóxia Celular/efeitos dos fármacos , Microglia/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Receptores Notch/metabolismo , Solução Salina Hipertônica/farmacologia , Animais , Isquemia Encefálica/imunologia , Isquemia Encefálica/patologia , Hipóxia Celular/fisiologia , Linhagem Celular , Modelos Animais de Doenças , Avaliação Pré-Clínica de Medicamentos , Masculino , Camundongos , Microglia/imunologia , Microglia/patologia , Óxido Nítrico Sintase Tipo II/metabolismo , Distribuição Aleatória , Ratos Sprague-Dawley , Traumatismo por Reperfusão/tratamento farmacológico , Traumatismo por Reperfusão/imunologia , Traumatismo por Reperfusão/patologia , Transdução de Sinais/efeitos dos fármacos
13.
Chemistry ; 23(33): 7990-7996, 2017 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-28326629

RESUMO

An unprecedented reversible dynamic transformation is reported in a metal-organic framework involving bond formation, which is accompanied by two important structural changes; achiral to chiral and two- to three-dimensions. Using two bent organic ligands (diimpym=4,6-di(1H-imidazol-1-yl)pyrimidine; H2 npta=5-nitroisophthalic acid) and CoII (NO3 )2 ⋅6 H2 O the coordination polymer Co(diimpym)(npta)⋅CH3 OH, (1⋅CH3 OH), was obtained solvothermally. Its structure consists of knitted pairs of square layers (44 -sql net) of five-coordinated Co and disordered methanol, and it crystallized in the achiral Pbca space group at room temperature. It undergoes a single crystal to single crystal (SC-SC) transformation to a 3D interpenetrated framework (α-polonium-type net, pcu) of six-coordinated Co and ordered methanol in the chiral P21 21 21 space group below 220 K. Most unusual is the dynamic temperature-dependent shortening of a Co⋅⋅⋅O connection from a non-bonded 2.640 Š(298 K) to a bonded 2.347 Šdistance (100 K) transforming the square pyramidal cobalt polyhedron to a distorted octahedron. The desolvated crystals (1) obtained at 480 K retain the full crystallinity and crystallize in the achiral Pbca space group between 100 and 298 K but the dynamic shortening of the Co⋅⋅⋅O distance connecting the layers into the 3D pcu framework structure is observed. Following post-synthetic insertion of ethanol (1⋅CH3 CH2 OH) it does not exhibit the transformation and retains the knitted 2D achiral Pbca structure for all temperatures (100-298 K) and the ethanol is always disordered. The structural analyses thus conclude that the ordering of the methanol induces the chirality while the available space controls the dynamic motion of the knitted 2D networks into the 3D interpenetrated framework. Consequently, 1 selectively adsorbs CO2 to N2 and exhibits Type-III isotherms indicating dynamic motion of the 2D networks to accommodate the CO2 at 273 and 298 K in contrast to the rigidity of the 3D framework at 77 K preventing N2 from penetrating the solid. The magnetic properties are also reported.

15.
J Neuroinflammation ; 11: 102, 2014 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-24916922

RESUMO

BACKGROUND: Hypertonic saline (HS) has been successfully used clinically for treatment of various forms of cerebral edema. Up-regulated expression of Na-K-Cl Cotransporter 1 (NKCC1) and inflammatory mediators such as tumor necrosis factor alpha (TNF-α) and interleukin-1 beta (IL-1ß) has been demonstrated to be closely associated with the pathogenesis of cerebral edema resulting from a variety of brain injuries. This study aimed to explore if alleviation of cerebral edema by 10% HS might be effected through down-regulation of inflammatory mediator expression in the microglia, and thus result in decreased NKCC1 expression in astrocytes in the cerebral cortex bordering the ischemic core. METHODS: The Sprague-Dawley (SD) rats that underwent right-sided middle cerebral artery occlusion (MCAO) were used for assessment of NKCC1, TNF-α and IL-1ß expression using Western blotting, double immunofluorescence and real time RT-PCR, and the model also was used for evaluation of brain water content (BWC) and infarct size. SB203580 and SP600125, specific inhibitors of the p38 and JNK signaling pathways, were used to treat primary microglia cultures to determine whether the two signaling pathways were required for the inhibition of HS on microglia expressing and secreting TNF-α and IL-1ß using Western blotting, double immunofluorescence and enzyme-linked immunosorbent assay (ELISA). The effect of TNF-α and IL-1ß on NKCC1 expression in primary astrocyte cultures was determined. In addition, the direct inhibitory effect of HS on NKCC1 expression in primary astrocytes was also investigated by Western blotting, double immunofluorescence and real time RT-PCR. RESULTS: BWC and infarct size decreased significantly after 10% HS treatment. TNF-α and IL-1ß immunoexpression in microglia was noticeably decreased. Concomitantly, NKCC1 expression in astrocytes was down-regulated. TNF-α and IL-1ß released from the primary microglia subjected to hypoxic exposure and treatment with 100 mM HS were decreased. NKCC1 expression in primary astrocytes was concurrently and progressively down-regulated with decreasing concentration of exogenous TNF-α and IL-1ß. Additionally, 100 mM HS directly inhibited NKCC1 up-regulation in astrocytes under hypoxic condition. CONCLUSIONS: The results suggest that 10% HS alleviates cerebral edema through inhibition of the NKCC1 Cotransporter, which is mediated by attenuation of TNF-α and IL-1ß stimulation on NKCC1.


Assuntos
Edema Encefálico/tratamento farmacológico , Citocinas/metabolismo , Microglia/efeitos dos fármacos , Solução Salina Hipertônica/uso terapêutico , Membro 2 da Família 12 de Carreador de Soluto/metabolismo , Regulação para Cima/efeitos dos fármacos , Animais , Edema Encefálico/etiologia , Edema Encefálico/patologia , Células Cultivadas , Modelos Animais de Doenças , Lateralidade Funcional , Proteína Glial Fibrilar Ácida/metabolismo , Infarto da Artéria Cerebral Média/complicações , Interleucina-1beta/metabolismo , Masculino , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Membro 2 da Família 12 de Carreador de Soluto/genética , Fatores de Tempo , Fator de Necrose Tumoral alfa/metabolismo
16.
Environ Sci Technol ; 48(2): 938-46, 2014 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-24328143

RESUMO

Soil and leaf litter are significant global sources of small oxidized volatile organic compounds, VOCs (e.g., methanol and acetaldehyde). They may also be significant sources of larger VOCs that could act as precursors to secondary organic aerosol (SOA) formation. To investigate this, soil and leaf litter samples were collected from the University of Idaho Experimental Forest and transported to the laboratory. There, the VOC emissions were characterized and used to drive SOA formation via dark, ozone-initiated reactions. Monoterpenes dominated the emission profile with emission rates as high as 228 µg-C m(-2) h(-1). The composition of the SOA produced was similar to biogenic SOA formed from oxidation of ponderosa pine emissions and α-pinene. Measured soil and litter monoterpene emission rates were compared with modeled canopy emissions. Results suggest surface soil and litter monoterpene emissions could range from 12 to 136% of canopy emissions in spring and fall. Thus, emissions from leaf litter may potentially extend the biogenic emissions season, contributing to significant organic aerosol formation in the spring and fall when reduced solar radiation and temperatures reduce emissions from living vegetation.


Assuntos
Aerossóis/análise , Poluentes Atmosféricos/análise , Poluição do Ar/análise , Compostos Orgânicos/análise , Folhas de Planta/química , Solo/química , Florestas , Oxirredução , Estações do Ano , Terpenos/análise , Fatores de Tempo , Compostos Orgânicos Voláteis/análise
17.
Org Lett ; 26(24): 5092-5097, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38848493

RESUMO

New carbonyl sulfoxonium ylide glyco-reagents have been developed, enabling the synthesis of versatile heteroarene C-glycosides through a Ru-catalyzed C-H activation/annulation strategy. These reactions tolerate various saccharide donors and represent a significant advance in the stereoselective synthesis of heterocyclic C-glycosides. Furthermore, the strategy and methods could be applied to large-scale reactions and late-stage modifications of some structurally complex natural products or drugs.

18.
Chem Commun (Camb) ; 60(5): 598-601, 2024 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-38099839

RESUMO

A new Cp*Rh(III)-catalyzed regioselective cyclization reaction of aromatic amides with allenes is reported. The use of allenyl derivatives bearing a directing-group assistant as a reaction promoter was the key to the success of this protocol. In this catalytic system, N-(pivaloyloxy)benzamide substrates react with allenes via Rh-σ-alkenyl intermediates, while N-(pivaloyloxy) indol substrates react via Rh-π-allyl intermediates. These reactions were characterized by mild reaction conditions, a broad substrate scope, and high functional-group compatibility to yield several high-value isoquinolinone and pyrimido[1,6-a]indol-1(2H)-one skeleton-containing compounds. The synthetic applications and primary mechanisms were also investigated.

19.
EClinicalMedicine ; 72: 102595, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38638180

RESUMO

Background: Endovascular therapy (EVT) was demonstrated effective in acute large vessel occlusion (LVO) with large infarction. Revealing subgroups of patients who would or would not benefit from EVT will further inform patient selection for EVT. Methods: This post-hoc analysis of the ANGEL-ASPECT trial, a randomised controlled trial of 456 adult patients with acute anterior-circulation LVO and large infarction, defined by ASPECTS 3-5 or infarct core volume 70-100 mL, enrolled from 46 centres across China, between October 2, 2020 and May 18, 2022. Patients were randomly assigned (1:1) to receiving EVT and medical management or medical management alone. One patient withdrew consent, 455 patients were included in this post-hoc analysis and categorised into 4 subgroups by lower or higher NIHSS (< or ≥16) and smaller or larger infarct core (< or ≥70 mL). Those with lower NIHSS & smaller core, and higher NIHSS & larger core were considered clinical-radiological matched subgroups; otherwise clinical-radiological mismatched subgroups. Primary outcome was 90-day modified Rankin Scale (mRS). ANGEL-ASPECT is registered with ClinicalTrials.gov, NCT04551664. Findings: Overall, 139 (30.5%) patients had lower NIHSS & smaller core, 106 (23.3%) higher NIHSS & larger core, 130 (28.6%) higher NIHSS & smaller core, and 80 (17.6%) lower NIHSS & larger core. There was significant ordinal shift in the 90-day mRS toward a better outcome with EVT in clinical-radiological matched subgroups: lower NIHSS & smaller core (generalised OR, 1.76; 95% CI, 1.18-2.62; p = 0.01) and higher NIHSS & larger core (1.64; 1.06-2.54; 0.01); but not in the two clinical-radiological mismatched subgroups. Interpretation: Our findings suggested that in patients with anterior-circulation LVO and large infarction, EVT was associated with improved 90-day functional outcomes in those with matched clinical and radiological severities, but not in those with mismatched clinical and radiological severities. Simultaneous consideration of stroke severity and infarct core volume may inform patient selection for EVT. Funding: Unrestricted grants from industry [Covidien Healthcare International Trading (Shanghai), Johnson & Johnson MedTech, Genesis MedTech (Shanghai), and Shanghai HeartCare Medical Technology].

20.
J Neurointerv Surg ; 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38697808

RESUMO

BACKGROUND: The relationship between post-endovascular thrombectomy (EVT) blood pressure (BP) and outcomes in patients with acute ischemic stroke (AIS) remains contentious. We aimed to explore whether this association differs with different cerebral perfusion statuses post-EVT. METHODS: In a multicenter observational study of patients with AIS with large vessel occlusion who underwent EVT, we enrolled those who accepted CT perfusion (CTP) imaging within 24 hours post-EVT. We recorded post-EVT systolic (SBP) and diastolic BP. Patients were stratified into favorable perfusion and unfavorable perfusion groups based on the hypoperfusion intensity ratio (HIR) on CTP. The primary outcome was good functional outcome (90-day modified Rankin Scale score of ≤3). Secondary outcomes included early neurological deterioration, infarct size growth, and symptomatic intracranial hemorrhage. RESULTS: Of the 415 patients studied (mean age 62 years, 75% male), 233 (56%) achieved good functional outcomes. Logistic regression showed that post-EVT HIR and 24-hour mean SBP were significantly associated with functional outcomes. Among the 326 (79%) patients with favorable perfusion, SBP <140 mmHg was associated with a higher percentage of good functional outcomes compared with SBP ≥140 mmHg (68% vs 52%; aOR 1.70 (95% CI 1.00 to 2.89), P=0.04). However, no significant difference was observed between SBP and functional outcomes in the unfavorable perfusion group. There was also no discernible difference between SBP and secondary outcomes across the different perfusion groups. CONCLUSIONS: In patients with favorable perfusion post-EVT, SBP <140 mmHg was associated with good functional outcomes, which underscores the need for further investigations with larger sample sizes or a more individualized BP management strategy. CLINICAL TRIAL REGISTRATION: ChiCTR1900022154.

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