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1.
Proc Natl Acad Sci U S A ; 118(6)2021 02 09.
Artigo em Inglês | MEDLINE | ID: mdl-33536341

RESUMO

Tuberous sclerosis complex (TSC) is caused by mutations in either TSC1 or TSC2 genes and affects multiple organs, including kidney, lung, and brain. In the kidney, TSC presents with the enlargement of benign tumors (angiomyolipomata) and cysts, which eventually leads to kidney failure. The factors promoting cyst formation and tumor growth in TSC are incompletely understood. Here, we report that mice with principal cell-specific inactivation of Tsc1 develop numerous cortical cysts, which are overwhelmingly composed of hyperproliferating A-intercalated (A-IC) cells. RNA sequencing and confirmatory expression studies demonstrated robust expression of Forkhead Transcription Factor 1 (Foxi1) and its downstream targets, apical H+-ATPase and cytoplasmic carbonic anhydrase 2 (CAII), in cyst epithelia in Tsc1 knockout (KO) mice but not in Pkd1 mutant mice. In addition, the electrogenic 2Cl-/H+ exchanger (CLC-5) is significantly up-regulated and shows remarkable colocalization with H+-ATPase on the apical membrane of cyst epithelia in Tsc1 KO mice. Deletion of Foxi1, which is vital to intercalated cells viability and H+-ATPase expression, completely abrogated the cyst burden in Tsc1 KO mice, as indicated by MRI images and histological analysis in kidneys of Foxi1/Tsc1 double-knockout (dKO) mice. Deletion of CAII, which is critical to H+-ATPase activation, caused significant reduction in cyst burden and increased life expectancy in CAII/Tsc1 dKO mice vs. Tsc1 KO mice. We propose that intercalated cells and their acid/base/electrolyte transport machinery (H+-ATPase/CAII/CLC-5) are critical to cystogenesis, and their inhibition or inactivation is associated with significant protection against cyst generation and/or enlargement in TSC.


Assuntos
Anidrase Carbônica II/genética , Fatores de Transcrição Forkhead/genética , Insuficiência Renal/genética , Proteína 1 do Complexo Esclerose Tuberosa/genética , Animais , Cistos/genética , Cistos/patologia , Modelos Animais de Doenças , Humanos , Rim/metabolismo , Rim/patologia , Camundongos , Mutação/genética , ATPases Translocadoras de Prótons/genética , Insuficiência Renal/patologia , Canais de Cátion TRPP/genética , Esclerose Tuberosa
2.
Plant Cell Environ ; 46(2): 363-378, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36444099

RESUMO

Photosynthesis is a process that uses solar energy to fix CO2 in the air and converts it into sugar, and ultimately powers almost all life activities on the earth. C3 photosynthesis is the most common form of photosynthesis in crops. Current efforts of increasing crop yields in response to growing global food requirement are mostly focused on improving C3 photosynthesis. In this review, we summarized the strategies of C3 photosynthesis improvement in terms of Rubisco properties and photorespiratory limitation. Potential engineered targets include Rubisco subunits and their catalytic sites, Rubisco assembly chaperones, and Rubisco activase. In addition, we reviewed multiple photorespiratory bypasses built by strategies of synthetic biology to reduce the release of CO2 and ammonia and minimize energy consumption by photorespiration. The potential strategies are suggested to enhance C3 photosynthesis and boost crop production.


Assuntos
Fenômenos Bioquímicos , Ribulose-Bifosfato Carboxilase , Ribulose-Bifosfato Carboxilase/metabolismo , Dióxido de Carbono , Fotossíntese/fisiologia , Produtos Agrícolas/fisiologia
3.
J Thromb Thrombolysis ; 56(1): 111-120, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37193832

RESUMO

Cerebral white matter lesions (WMLs) increase the risk of bleeding after intravenous thrombolysis (IVT) but are also considered to require IVT. Its risk factors and predictive models are still poorly studied. The aim of this study is to develop a clinically applicable model for post-IVT haemorrhage. It offers the possibility to prevent symptomatic intracranial hemorrhage (sICH) in patients with IVT in severe WMLs. A large single-center observational study conducted a retrospective analysis of IVT in patients with severe WMLs from January 2018 to December 2022. Univariate and multi-factor logistic regression results were used to construct nomogram model, and a series of validations were performed on the model. More than 2,000 patients with IVT were screened for inclusion in this study after cranial magnetic resonance imaging evaluation of 180 patients with severe WMLs, 28 of whom developed sICH. In univariate analysis, history of hypertension (OR 3.505 CI 2.257-4.752, p = 0.049), hyperlipidemia (OR 4.622 CI 3.761- 5.483, p < 0.001), the NIHSS score before IVT (OR 41.250 CI 39.212-43.288, p < 0.001), low-density lipoprotein levels (OR 1.995 CI 1.448-2.543, p = 0.013), cholesterol levels (OR 1.668 CI 1.246-2.090, p = 0.017), platelet count (OR 0.992 CI 0.985-0.999, p = 0.028), systolic blood pressure (OR 1.044 CI 1.022-1.066, p < 0.001), diastolic blood pressure (OR 1.047 CI 1.024-1.070, p < 0.001) were significantly associated with sICH. In a multifactorial analysis, the NIHSS score before IVT (OR 94.743 CI 92.311-97.175, p < 0.001), and diastolic blood pressure (OR 1.051 CI 1.005-1.097, p = 0.033) were considered to be significantly associated with sICH after IVT as risk factors for the occurrence of sICH. The four most significant factors from logistic regression are subsequently fitted to create a predictive model. The accuracy was verified using ROC curves, calibration curves, decision curves, and clinical impact curves, and the model was considered to have high accuracy (AUC 0.932, 95% 0.888-0.976). The NHISS score before IVT and diastolic blood pressure are independent risk factors for sICH after IVT in patients with severe WMLs. The models based on hyperlipidemia, the NIHSS score before IVT, low-density lipoprotein and diastolic blood pressure are highly accurate and can be applied clinically to provide a reliable predictive basis for IVT in patients with severe WMLs.


Assuntos
Acidente Vascular Cerebral , Substância Branca , Humanos , Fibrinolíticos/efeitos adversos , Acidente Vascular Cerebral/tratamento farmacológico , Hemorragia Cerebral/tratamento farmacológico , Estudos Retrospectivos , Nomogramas , Terapia Trombolítica/efeitos adversos , Hemorragias Intracranianas/induzido quimicamente , Resultado do Tratamento , Ativador de Plasminogênio Tecidual/uso terapêutico
4.
Int J Mol Sci ; 23(18)2022 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-36142437

RESUMO

Current imaging approaches used to monitor tumor progression can lack the ability to distinguish true progression from pseudoprogression. Simultaneous metabolic 2-deoxy-2-[18F]fluoro-D-glucose ([18F]FDG) positron emission tomography (PET) and magnetic resonance imaging (MRI) offers new opportunities to overcome this challenge by refining tumor identification and monitoring therapeutic responses to cancer immunotherapy. In the current work, spatial and quantitative analysis of tumor burden were performed using simultaneous [18F]FDG-PET/MRI to monitor therapeutic responses to a novel silicified cancer cell immunotherapy in a mouse model of disseminated serous epithelial ovarian cancer. Tumor progression was validated by bioluminescence imaging of luciferase expressing tumor cells, flow cytometric analysis of immune cells in the tumor microenvironment, and histopathology. While PET demonstrated the presence of metabolically active cancer cells through [18F]FDG uptake, MRI confirmed cancer-related accumulation of ascites and tissue anatomy. This approach provides complementary information on disease status without a confounding signal from treatment-induced inflammation. This work provides a possible roadmap to facilitate accurate monitoring of therapeutic responses to cancer immunotherapies.


Assuntos
Fluordesoxiglucose F18 , Neoplasias Ovarianas , Animais , Feminino , Glucose , Humanos , Imunoterapia , Imageamento por Ressonância Magnética/métodos , Camundongos , Neoplasias Ovarianas/diagnóstico por imagem , Neoplasias Ovarianas/terapia , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Tomografia por Emissão de Pósitrons/métodos , Compostos Radiofarmacêuticos , Microambiente Tumoral
5.
Mol Cell Biochem ; 476(8): 2951-2961, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33755879

RESUMO

Circular RNAs (circRNAs) are implicated in the tumorigenesis of human cancers. However, the effects of circRNAs on laryngeal squamous cell carcinoma (LSCC) are largely unknown. Here, we aimed to explore the roles of circ_0023028 in LSCC development. Quantitative real-time polymerase chain reaction (qRT-PCR) was performed to measure circ_0023028, miR-486-3p, and Lin-Isl-Mec (LIM) and SH3 domain protein 1 (LASP1) mRNA. The characteristics of circ_0023028 were determined by RNase R digestion assay and Actinomycin D assay. Cell Counting Kit-8 (CCK-8) assay and colony formation assay were utilized for cell proliferation. Transwell assay was adopted for cell invasion and migration. Flow cytometry analysis was carried out to analyze cell cycle and apoptosis. RNA pull-down assay and dual-luciferase reporter assay were used to explore the association between miR-486-3p and circ_0023028 or LASP1. Western blot assay was adopted to measure LASP1 protein level. Murine xenograft model was executed to investigate the function of circ_0023028 in vivo. High expression of circ_0023028 was observed in LSCC tissues and cells. Circ_0023028 was stable and possessed a loop structure. Circ_0023028 silencing suppressed LSCC cell proliferation, metastasis and cell cycle process and induced apoptosis in vitro and hampered tumor growth in vivo. Further mechanism analysis demonstrated that circ_0023028 could sponge miR-486-3p to regulate LASP1 expression in LSCC cells. The malignant behaviors of LSCC cells mediated by circ_0023028 knockdown were rescued by the inhibition of miR-486-3p. Moreover, miR-486-3p suppressed LSCC cell progression via binding to LASP1. Circ_0023028 knockdown might impede the progression of LSCC by regulating miR-486-3p/LASP1 axis, which could provide a novel insight on the mechanism of LSCC progression.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Biomarcadores Tumorais/metabolismo , Carcinoma de Células Escamosas/patologia , Proteínas do Citoesqueleto/metabolismo , Regulação Neoplásica da Expressão Gênica , Proteínas com Domínio LIM/metabolismo , Neoplasias Laríngeas/patologia , MicroRNAs/genética , RNA Circular/genética , Proteínas Adaptadoras de Transdução de Sinal/genética , Animais , Apoptose , Biomarcadores Tumorais/genética , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/metabolismo , Proliferação de Células , Proteínas do Citoesqueleto/genética , Progressão da Doença , Feminino , Humanos , Proteínas com Domínio LIM/genética , Neoplasias Laríngeas/genética , Neoplasias Laríngeas/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Pessoa de Meia-Idade , Prognóstico , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
6.
Neuroimage ; 223: 117343, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32898676

RESUMO

Chronic pain often predicts the onset of psychological distress. Symptoms including anxiety and depression after pain chronification reportedly are caused by brain remodeling/recruitment of the limbic and reward/aversion circuitries. Pain is the primary precipitating factor that has caused opioid overprescribing and continued overuse of opioids leading to the current opioid epidemic. Yet experimental pain therapies often fail in clinical trials. Better understanding of underlying pathologies contributing to pain chronification is needed to address these chronic pain related issues. In the present study, a chronic neuropathic pain model persisting 10 weeks was studied. The model develops both anxiety- and pain-related behavioral measures to mimic clinical pain. The manganese-enhanced magnetic resonance imaging (MEMRI) utilized improved MRI signal contrast in brain regions with higher neuronal activity in the rodent chronic constriction trigeminal nerve injury (CCI-ION) model. T1-weighted MEMRI signal intensity was increased compared to controls in supraspinal regions of the anxiety and aversion circuitry, including anterior cingulate gyrus (ACC), amygdala, habenula, caudate, ventrolateral and dorsomedial periaqueductal gray (PAG). Despite continuing mechanical hypersensitivity, MEMRI T1 signal intensity as the neuronal activity measure, was not significantly different in thalamus and decreased in somatosensory cortex (S1BF) of CCI-ION rats compared to naïve controls. This is consistent with decreased fMRI BOLD signal intensity in thalamus and cortex of patients with longstanding trigeminal neuropathic pain reportedly associated with gray matter volume decrease in these regions. Significant increase in MEMRI T2 signal intensity in thalamus of CCI-ION animals was indication of tissue water content, cell dysfunction and/or reactive astrogliosis. Decreased T2 signal intensity in S1BF cortex of rats with CCI-ION was similar to findings of reduced T2 signals in clinical patients with chronic orofacial pain indicating prolonged astrocyte activation. These findings support use of MEMRI and chronic rodent models for preclinical studies and therapeutic trials to reveal brain sites activated only after neuropathic pain has persisted in timeframes relevant to clinical pain and to observe treatment effects not possible in short-term models which do not have evidence of anxiety-like behaviors. Potential improvement is predicted in the success rate of preclinical drug trials in future studies with this model.


Assuntos
Ansiedade/fisiopatologia , Encéfalo/fisiopatologia , Neuralgia/fisiopatologia , Animais , Ansiedade/etiologia , Mapeamento Encefálico/métodos , Meios de Contraste , Imageamento por Ressonância Magnética/métodos , Masculino , Manganês , Vias Neurais/fisiopatologia , Neuralgia/complicações , Ratos Sprague-Dawley
7.
J Neurosci Res ; 95(4): 1025-1035, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-27452502

RESUMO

Traumatic brain injury (TBI) is a major public health issue, with recently increased awareness of the potential long-term sequelae of repetitive injury. Although TBI is common, objective diagnostic tools with sound neurobiological predictors of outcome are lacking. Indeed, such tools could help to identify those at risk for more severe outcomes after repetitive injury and improve understanding of biological underpinnings to provide important mechanistic insights. We tested the hypothesis that acute and subacute pathological injury, including the microgliosis that results from repeated mild closed head injury (rmCHI), is reflected in susceptibility-weighted magnetic resonance imaging and diffusion-tensor imaging microstructural abnormalities. Using a combination of high-resolution magnetic resonance imaging, stereology, and quantitative PCR, we studied the pathophysiology of male mice that sustained seven consecutive mild traumatic brain injuries over 9 days in acute (24 hr) and subacute (1 week) time periods. rmCHI induced focal cortical microhemorrhages and impaired axial diffusivity at 1 week postinjury. These microstructural abnormalities were associated with a significant increase in microglia. Notably, microgliosis was accompanied by a change in inflammatory microenvironment defined by robust spatiotemporal alterations in tumor necrosis factor-α receptor mRNA. Together these data contribute novel insight into the fundamental biological processes associated with repeated mild brain injury concomitant with subacute imaging abnormalities in a clinically relevant animal model of repeated mild TBI. These findings suggest new diagnostic techniques that can be used as biomarkers to guide the use of future protective or reparative interventions. © 2016 Wiley Periodicals, Inc.


Assuntos
Lesões Encefálicas Traumáticas/patologia , Encéfalo/patologia , Microglia/patologia , Fibras Nervosas Mielinizadas/patologia , Animais , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Lesões Encefálicas Traumáticas/complicações , Lesões Encefálicas Traumáticas/diagnóstico por imagem , Proteínas de Ligação ao Cálcio/metabolismo , Citocinas/genética , Citocinas/metabolismo , Imagem de Tensor de Difusão , Modelos Animais de Doenças , Regulação da Expressão Gênica/fisiologia , Hemorragias Intracranianas/etiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Proteínas dos Microfilamentos/metabolismo , Microglia/metabolismo , Óxido Nítrico Sintase Tipo II/genética , Óxido Nítrico Sintase Tipo II/metabolismo , RNA Mensageiro/metabolismo , Estatísticas não Paramétricas
8.
J Neurosci ; 35(36): 12446-64, 2015 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-26354913

RESUMO

A multifunctional microRNA, miR-155, has been recently recognized as an important modulator of numerous biological processes. In our previous in vitro studies, miR-155 was identified as a potential regulator of the endothelial morphogenesis. The present study demonstrates that in vivo inhibition of miR-155 supports cerebral vasculature after experimental stroke. Intravenous injections of a specific miR-155 inhibitor were initiated at 48 h after mouse distal middle cerebral artery occlusion (dMCAO). Microvasculature in peri-infarct area, infarct size, and animal functional recovery were assessed at 1, 2, and 3 weeks after dMCAO. Using in vivo two-photon microscopy, we detected improved blood flow and microvascular integrity in the peri-infarct area of miR-155 inhibitor-injected mice. Electron microscopy revealed that, in contrast to the control group, these animals demonstrated well preserved capillary tight junctions (TJs). Western blot analysis data indicate that improved TJ integrity in the inhibitor-injected animals could be associated with stabilization of the TJ protein ZO-1 and mediated by the miR-155 target protein Rheb. MRI analysis showed significant (34%) reduction of infarct size in miR-155 inhibitor-injected animals at 21 d after dMCAO. Reduced brain injury was confirmed by electron microscopy demonstrating decreased neuronal damage in the peri-infarct area of stroke. Preservation of brain tissue was reflected in efficient functional recovery of inhibitor-injected animals. Based on our findings, we propose that in vivo miR-155 inhibition after ischemia supports brain microvasculature, reduces brain tissue damage, and improves the animal functional recovery. Significance statement: In the present study, we investigated an effect of the in vivo inhibition of a microRNA, miR-155, on brain recovery after experimental cerebral ischemia. To our knowledge, this is the first report describing the efficiency of intravenous anti-miRNA injections in a mouse model of ischemic stroke. The role of miRNAs in poststroke revascularization has been unexplored and in vivo regulation of miRNAs during the subacute phase of stroke has not yet been proposed. Our investigation introduces a new and unexplored approach to cerebral regeneration: regulation of poststroke angiogenesis and recovery through direct modulation of specific miRNA activity. We expect that our findings will lead to the development of novel strategies for regulating neurorestorative processes in the postischemic brain.


Assuntos
Infarto da Artéria Cerebral Média/terapia , MicroRNAs/genética , Terapêutica com RNAi , Animais , Injeções Intravenosas , Camundongos , Camundongos Endogâmicos C57BL , Microvasos/metabolismo , Microvasos/patologia , Oligonucleotídeos Antissenso/administração & dosagem , Oligonucleotídeos Antissenso/uso terapêutico , Proteínas de Junções Íntimas/metabolismo , Junções Íntimas/metabolismo , Junções Íntimas/ultraestrutura
9.
Neurobiol Dis ; 95: 12-21, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27388935

RESUMO

Zinc ions are stored in synaptic vesicles and cerebral ischemia triggers their release from the terminals of neurons. Zinc accumulation in neurons has been shown to play an important role in neuronal death following ischemia. However, almost nothing is known about whether zinc is involved in ischemia-induced blood-brain barrier (BBB) disruption. Herein, we investigated the contribution of zinc to ischemia-induced acute BBB disruption and the possible molecular mechanisms using both cellular and animal models of cerebral ischemia. Zinc greatly increased BBB permeability and exacerbated the loss of tight junction proteins (Occludin and Claudin-5) in the endothelial monolayer under oxygen glucose deprivation conditions. In cerebral ischemic rats, a dramatically elevated level of zinc accumulation in microvessels themselves was observed in isolated microvessels and in situ, showing the direct interaction of zinc on ischemic microvessels. Treatment with a specific zinc chelator N,N,N',N'-tetrakis(2-pyridylmethyl) ethylenediamine (TPEN), even at 60-min post-ischemia onset, could greatly attenuate BBB permeability in the ischemic rats as measured by Evan's Blue extravasation, edema volume and magnetic resonance imaging. Furthermore, zinc accumulation in microvessels activated the superoxide/matrix metalloproteinase-9/-2 pathway, which leads to the loss of tight junction proteins (Occludin and Claudin-5) and death of endothelial cells in microvessels themselves. Our findings reveal a novel mechanism of cerebral ischemia-induced BBB damage, and implicate zinc as an effective and viable new target for reducing acute BBB damage following ischemic stroke.


Assuntos
Barreira Hematoencefálica/patologia , Isquemia Encefálica/metabolismo , Permeabilidade/efeitos dos fármacos , Zinco/metabolismo , Animais , Barreira Hematoencefálica/efeitos dos fármacos , Isquemia Encefálica/fisiopatologia , Etilenodiaminas/farmacologia , Infarto da Artéria Cerebral Média/patologia , Masculino , Metaloproteinase 9 da Matriz/metabolismo , Ratos Sprague-Dawley , Traumatismo por Reperfusão/tratamento farmacológico , Traumatismo por Reperfusão/metabolismo , Acidente Vascular Cerebral/tratamento farmacológico , Acidente Vascular Cerebral/patologia , Proteínas de Junções Íntimas/metabolismo
10.
Crit Care Med ; 44(8): e633-8, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-26974548

RESUMO

OBJECTIVES: We recently showed that increased intracranial pressure to 50 mm Hg in the healthy rat brain results in microvascular shunt flow characterized by tissue hypoxia, edema, and increased blood-brain barrier permeability. We now determined whether increased intracranial pressure results in neuronal injury by Fluoro-Jade stain and whether changes in cerebral blood flow and cerebral metabolic rate for oxygen suggest nonnutritive microvascular shunt flow. DESIGN: Intracranial pressure was elevated by a reservoir of artificial cerebrospinal fluid connected to the cisterna magna. Arterial blood gases, cerebral arterial-venous oxygen content difference, and cerebral blood flow by MRI were measured. Fluoro-Jade stain neurons were counted in histologic sections of the right and left dorsal and lateral cortices and hippocampus. SETTING: University laboratory. SUBJECTS: Male Sprague Dawley rats. INTERVENTIONS: Arterial pressure support if needed by IV dopamine infusion and base deficit corrected by sodium bicarbonate. MEASUREMENTS AND MAIN RESULTS: Fluoro-Jade stain neurons increased 2.5- and 5.5-fold at intracranial pressures of 30 and 50 mm Hg and cerebral perfusion pressures of 57 ± 4 (mean ± SEM) and 47 ± 6 mm Hg, respectively (p < 0.001) (highest in the right and left cortices). Voxel frequency histograms of cerebral blood flow showed a pattern consistent with microvascular shunt flow by dispersion to higher cerebral blood flow at high intracranial pressure and decreased cerebral metabolic rate for oxygen. CONCLUSIONS: High intracranial pressure likely caused neuronal injury because of a transition from normal capillary flow to nonnutritive microvascular shunt flow resulting in tissue hypoxia and edema, and it is manifest by a reduction in the cerebral metabolic rate for oxygen.


Assuntos
Circulação Cerebrovascular/fisiologia , Hipertensão Intracraniana/fisiopatologia , Neurônios/patologia , Animais , Velocidade do Fluxo Sanguíneo/fisiologia , Fluoresceínas , Pressão Intracraniana , Imageamento por Ressonância Magnética , Masculino , Oxigênio/sangue , Ratos , Ratos Sprague-Dawley
11.
J Neuroinflammation ; 12: 26, 2015 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-25889169

RESUMO

BACKGROUND: Minocycline reduces reperfusion injury by inhibiting matrix metalloproteinases (MMPs) and microglia activity after cerebral ischemia. Prior studies of minocycline investigated short-term neuroprotective effects during subacute stage of stroke; however, the late effects of minocycline against early reperfusion injury on neurovascular remodeling are less well studied. We have shown that spontaneous angiogenesis vessels in ischemic brain regions have high blood-brain barrier (BBB) permeability due to lack of major tight junction proteins (TJPs) in endothelial cells at three weeks. In the present study, we longitudinally investigated neurological outcome, neurovascular remodeling and microglia/macrophage alternative activation after spontaneous and minocycline-induced stroke recovery. METHODS: Adult spontaneously hypertensive rats had a 90 minute transient middle cerebral artery occlusion. At the onset of reperfusion they received a single dose of minocycline (3 mg/kg intravenously) or a vehicle. They were studied at multiple time points up to four weeks with magnetic resonance imaging (MRI), immunohistochemistry and biochemistry. RESULTS: Minocycline significantly reduced the infarct size and prevented tissue loss in the ischemic hemispheres compared to vehicle-treated rats from two to four weeks as measured with MRI. Cerebral blood flow measured with arterial spin labeling (ASL) showed that minocycline improved perfusion. Dynamic contrast-enhanced MRI indicated that minocycline reduced BBB permeability accompanied with higher levels of TJPs measured with Western blot. Increased MMP-2 and -3 were detected at four weeks. Active microglia/macrophage, surrounding and within the peri-infarct areas, expressed YM1, a marker of M2 microglia/macrophage activation, at four weeks. These microglia/macrophage expressed both pro-inflammatory factors tumor necrosis factors-α (TNF-α) and interleukin-1ß (IL-1ß) and anti-inflammatory factors transforming growth factor-ß (TGF-ß) and interleukin-10 (IL-10). Treatment with minocycline significantly reduced levels of TNF-α and IL-1ß, and increased levels of TGF-ß, IL-10 and YM1. CONCLUSIONS: Early minocycline treatment against reperfusion injury significantly promotes neurovascular remodeling during stroke recovery by reducing brain tissue loss, enhancing TJP expression in ischemic brains and facilitating neuroprotective phenotype alternative activation of microglia/macrophages.


Assuntos
Barreira Hematoencefálica/efeitos dos fármacos , Infarto da Artéria Cerebral Média/tratamento farmacológico , Infarto da Artéria Cerebral Média/patologia , Macrófagos/efeitos dos fármacos , Microglia/efeitos dos fármacos , Minociclina/uso terapêutico , Recuperação de Função Fisiológica/efeitos dos fármacos , Animais , Barreira Hematoencefálica/fisiologia , Circulação Cerebrovascular/efeitos dos fármacos , Citocinas/metabolismo , Modelos Animais de Doenças , Regulação da Expressão Gênica/efeitos dos fármacos , Imageamento por Ressonância Magnética , Masculino , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Ratos , Ratos Endogâmicos SHR , Recombinases Rec A/metabolismo , Reperfusão , Fatores de Tempo
12.
Toxicol Appl Pharmacol ; 275(2): 73-8, 2014 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-24412707

RESUMO

Abuse of methamphetamine (METH) is a major and significant societal problem in the US, as a number of studies have suggested that METH is associated with increased cerebrovascular events, hemorrhage or vasospasm. Although cellular and molecular mechanisms involved in METH-induced toxicity are not completely understood, changes in brain O2 may play an important role and contribute to METH-induced neurotoxicity including dopaminergic receptor degradation. Given that O2 is the terminal electron acceptor for many enzymes that are important in brain function, the impact of METH on brain tissue pO2 in vivo remains largely uncharacterized. This study investigated striatal tissue pO2 changes in male C57BL/6 mice (16-20 g) following METH administration using EPR oximetry, a highly sensitive modality to measure pO2 in vivo, in situ and in real time. We demonstrate that 20 min after a single injection of METH (8 mg/kg i.v.), the striatal pO2 was reduced to 81% of the pretreatment level and exposure to METH for 3 consecutive days further attenuated striatal pO2 to 64%. More importantly, pO2 did not recover fully to control levels even 24 h after administration of a single dose of METH and continual exposure to METH exacerbates the condition. We also show a reduction in cerebral blood flow associated with a decreased brain pO2 indicating an ischemic condition. Our findings suggests that administration of METH can attenuate brain tissue pO2, which may lead to hypoxic insult, thus a risk factor for METH-induced brain injury and the development of stroke in young adults.


Assuntos
Hipóxia Encefálica/patologia , Metanfetamina/toxicidade , Neostriado/efeitos dos fármacos , Oximetria/métodos , Oxigênio/metabolismo , Animais , Circulação Cerebrovascular , Relação Dose-Resposta a Droga , Espectroscopia de Ressonância de Spin Eletrônica , Hipóxia Encefálica/induzido quimicamente , Masculino , Metanfetamina/administração & dosagem , Camundongos , Camundongos Endogâmicos C57BL , Neostriado/patologia
13.
Med Phys ; 51(1): 224-238, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37401203

RESUMO

BACKGROUND: Photon counting detectors (PCDs) provide higher spatial resolution, improved contrast-to-noise ratio (CNR), and energy discriminating capabilities. However, the greatly increased amount of projection data in photon counting computed tomography (PCCT) systems becomes challenging to transmit through the slip ring, process, and store. PURPOSE: This study proposes and evaluates an empirical optimization algorithm to obtain optimal energy weights for energy bin data compression. This algorithm is universally applicable to spectral imaging tasks including 2 and 3 material decomposition (MD) tasks and virtual monoenergetic images (VMIs). This method is simple to implement while preserving spectral information for the full range of object thicknesses and is applicable to different PCDs, for example, silicon detectors and CdTe detectors. METHODS: We used realistic detector energy response models to simulate the spectral response of different PCDs and an empirical calibration method to fit a semi-empirical forward model for each PCD. We numerically optimized the optimal energy weights by minimizing the average relative Cramér-Rao lower bound (CRLB) due to the energy-weighted bin compression, for MD and VMI tasks over a range of material area density ρ A , m ${\rho }_{A,m}$ (0-40 g/cm2 water, 0-2.16 g/cm2 calcium). We used Monte Carlo simulation of a step wedge phantom and an anthropomorphic head phantom to evaluate the performance of this energy bin compression method in the projection domain and image domain, respectively. RESULTS: The results show that for 2 MD, the energy bin compression method can reduce PCCT data size by 75% and 60%, with an average variance penalty of less than 17% and 3% for silicon and CdTe detectors, respectively. For 3 MD tasks with a K-edge material (iodine), this method can reduce the data size by 62.5% and 40% with an average variance penalty of less than 12% and 13% for silicon and CdTe detectors, respectively. CONCLUSIONS: We proposed an energy bin compression method that is broadly applicable to different PCCT systems and object sizes, with high data compression ratio and little loss of spectral information.


Assuntos
Compostos de Cádmio , Pontos Quânticos , Raios X , Silício , Telúrio , Fótons , Imagens de Fantasmas
14.
Aging Dis ; 2024 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-38916732

RESUMO

Endothelial dysfunction and blood-brain barrier (BBB) leakage have been suggested as a fundamental role in the development of cerebral small vessel disease (SVD) pathology. However, the molecular and cellular mechanisms that link cerebral hypoxic hypoperfusion and BBB disruption remain elusive. Sphingosine-1-phosphate (S1P) regulates the BBB integrity by binding to its receptor isoform 1 (S1PR1) on endothelial cells. This study tested the hypothesis that hypoxic hypoperfusion triggers capillary endothelial S1PR1 disruption, which compromises BBB integrity and leads to SVD-related neuropathological changes, using a chronic hypoxic hypoperfusion model with BBB dysfunction. Spontaneously hypertensive rat stroke-prone underwent unilateral carotid artery occlusion (UCAO) followed by a Japanese permissive diet (JPD) for up to 9 weeks. Selective S1PR1 agonist SEW2871 was used to activate S1PR1. Significant progressive reduction of S1PR1 was detected in rat brains from 4 to 9 weeks following UCAO/JPD onset, which was also detected in cerebral vasculature in human SVD. S1PR1 activation by SEW2871 significantly reduced lesions in both white and grey matter and ameliorated cerebral blood flow. SEW2871 reversed the loss of endothelial S1PR1 and tight junction proteins, and significantly attenuated UCAO/JPD induced accumulation of neuronal phosphorylated tau. This protective role of SEW2871 is associated with promotion of Akt phosphorylation and inhibition of S1PR2/Erk1/2 activation. Our data suggest S1PR1 signalling as a potential molecular mechanistic basis that links hypoxic hypoperfusion with BBB damage in the neuropathological cascades in SVD. The reversal of BBB disruption through pharmacological intervention of S1PR1 signalling likely reveals a novel therapeutic target for SVD.

15.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 30(6): 701-5, 2013 Dec.
Artigo em Zh | MEDLINE | ID: mdl-24327151

RESUMO

OBJECTIVE: To investigate polymorphisms of killer cell immunoglobulin-like receptor gene (KIR) in renal transplant recipients from southern Zhejiang. METHODS: KIR genotypes were analyzed by PCR-SSP in 416 renal transplant recipients, and the genotype frequencies were compared with populations from Eastern China and worldwide. RESULTS: All 16 known KIR genes were detected in the renal transplant recipients, and KIR2DL4, 3DL2-3, 3PD1 were found in all. As a pseudogene, 2DP1 has a high genotype frequency (99%). The frequencies of KIR2DL1, 2DL3, 3DL1, 2DS4 have ranged from 92.1% to 98.8%. Compared with 11 groups in Eastern China and other countries, the KIR2DL2 phenotype frequency was higher (34.6%) than those of Shanghai, Zhejiang and Jiangsu populations (P<0.05). Among 41 genotypes, three have not been reported previously. The most common genotype was AA1, with a frequency of 43.51%, which was significantly lower than those of Jiangsu and Northern Zhejiang. CONCLUSION: Renal transplant recipients from southern Zhejiang share similar features with Eastern China Han population with regard to KIR polymorphisms, but also have unique frequencies for KIR genotypes.


Assuntos
Transplante de Rim/métodos , Receptores KIR/genética , Adolescente , Adulto , Idoso , China , Feminino , Frequência do Gene , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo Genético , Adulto Jovem
16.
Sci Rep ; 13(1): 22375, 2023 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-38104231

RESUMO

Composites are widely used in high performance structures such as aerospace structures due to their excellent properties. The analysis of failure evolution of composite perforated structures by finite element simulation is of great significance for practical work as engineering composite structures often contain notches and voids. In this paper, the numerical simulation of failure evolution and failure modes of carbon fiber reinforced resin composite laminates with large openings was carried out. A UMAT subroutine was written based on the 3D Hashin-Ye failure criterion and progressive damage model theory. The characteristic length and viscosity coefficient were introduced into the model to reduce mesh dependency and improve computational convergence. The nonlinear shear constitutive relationship defined by the Ramberg-Osgood equation was introduced into the continuous damage degradation model. The effect of nonlinear shear on the failure evolution of laminates with different stacking sequence was studied.

17.
J Orthop Surg Res ; 18(1): 38, 2023 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-36639752

RESUMO

OBJECTIVE: To clarify the clinical efficacy of styloid incision truncation via percutaneous punching in treating styloid process (styloid) syndrome. METHODS: The clinical data of 40 styloid syndrome patients treated in our hospital from July 2018 to August 2021 were chosen and divided into an observation group and a control group in a random manner, with 20 cases in each. The control group received treatment with styloid truncation via an external cervical approach, and the observation group received treatment with styloid incision truncation via percutaneous punching. The operation time, intraoperative blood loss, length of truncated styloid, clinical efficacy, pain scores, postoperative complications and inflammatory cytokine levels were assessed in the both groups. RESULTS: The intraoperative blood loss, operation time, length of truncated styloid and hospital stay in the observation group were significantly lower than those in the control group (P < 0.05). VAS pain scores were higher in both groups after the operation compared to before the operation. However, the observation group showed a statistically significant reduction in comparison with the control group (P < 0.05). The treatment effectiveness and complication rates of the two groups exhibited significant differences (P < 0.05). After the operation, TNF-α, CRP, and IL-6 levels in both groups were elevated compared to those before the operation. The observation group, however, showed significant depletion compared to the control group (P < 0.05). CONCLUSION: Styloid incision truncation via percutaneous punching was not only effective in treating styloid syndrome, but also caused less trauma and fewer complications. It promotes patient recovery and requires a simple operation, making it worthy of promotion in hospitals.


Assuntos
Perda Sanguínea Cirúrgica , Ferida Cirúrgica , Humanos , Resultado do Tratamento , Complicações Pós-Operatórias , Dor , Estudos Retrospectivos
18.
Sci Rep ; 13(1): 13513, 2023 08 19.
Artigo em Inglês | MEDLINE | ID: mdl-37598251

RESUMO

Metastasis is a major cause of treatment failure and poor outcomes in cancer patients. The data used in the current study was downloaded from TCGA and GEO databases. Differentially expressed metastasis-related genes were identified and the biological functions were implemented. Kaplan-Meier analysis univariate, and, multivariate Cox regression analyses were performed to identify robust prognostic biomarkers, followed by construction of the risk model and nomogram. Gene set enrichment analysis was performed to identify pathways enriched in low- and high-risk groups. POLR2J3 and MYH11 were treated as prognostic biomarkers in LSCC and the risk model was constructed. Receiver operating characteristic curves revealed the good performance of the risk model. A nomogram with high accuracy was constructed, as evidenced by calibration and decision curves. Moreover, we found that the expressions of POLR2J3 and MYH11 was significantly higher in metastasis tissues compared with those in non-metastasis tissues by RT-qPCR and IHC. Our study identified novel metastasis-related prognostic biomarkers in LSCC and constructed a unique nomogram for predicting the prognosis of LSCC patients. Moreover, we explored the related mechanisms of metastasis-related genes in regulating LSCC.


Assuntos
Neoplasias de Cabeça e Pescoço , Nomogramas , Humanos , Prognóstico , Carcinoma de Células Escamosas de Cabeça e Pescoço , Biomarcadores
19.
J Neurotrauma ; 40(13-14): 1481-1494, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36869619

RESUMO

Abstract Traumatic brain injury (TBI) continues to be a major cause of death and disability worldwide. This study assessed the effectiveness of non-invasive vagus nerve stimulation (nVNS) in reducing brain lesion volume and improving neurobehavioral performance in a rat model of TBI. Animals were randomized into three experimental groups: (1) TBI with sham stimulation treatment (Control), (2) TBI treated with five lower doses (2-min) nVNS, and (3) TBI treated with five higher doses (2 × 2-min) nVNS. We used the gammaCore nVNS device to deliver stimulations. Magnetic resonance imaging studies were performed 1 and 7 days post-injury to confirm lesion volume. We observed smaller brain lesion volume in the lower dose nVNS group compared with the control group on days 1 and 7. The lesion volume for the higher dose nVNS group was significantly smaller than either the lower dose nVNS or the control groups on days 1 and 7 post-injury. The apparent diffusion coefficient differences between the ipsilateral and contralateral hemispheres on day 1 were significantly smaller for the higher dose (2 × 2 min) nVNS group than for the control group. Voxel-based morphometry analysis revealed an increase in the ipsilateral cortical volume in the control group caused by tissue deformation and swelling. On day 1, these abnormal volume changes were 13% and 55% smaller in the lower dose and higher dose nVNS groups, respectively, compared with the control group. By day 7, nVNS dampened cortical volume loss by 35% and 89% in the lower dose and higher dose nVNS groups, respectively, compared with the control group. Rotarod, beam walking, and anxiety performances were significantly improved in the higher-dose nVNS group on day 1 compared with the control group. The anxiety indices were also improved on day 7 post-injury compared with the control and the lower-dose nVNS groups. In conclusion, the higher dose nVNS (five 2 × 2-min stimulations) reduced brain lesion volume to a level that further refined the role of nVNS therapy for the acute treatment of TBI. Should nVNS prove effective in additional pre-clinical TBI models and later in clinical settings, it would have an enormous impact on the clinical practice of TBI in both civilian and military settings, as it can easily be adopted into routine clinical practice.


Assuntos
Lesões Encefálicas Traumáticas , Estimulação do Nervo Vago , Ratos , Animais , Estimulação do Nervo Vago/métodos , Método Duplo-Cego , Lesões Encefálicas Traumáticas/diagnóstico por imagem , Lesões Encefálicas Traumáticas/terapia , Encéfalo/diagnóstico por imagem
20.
Sci Data ; 10(1): 701, 2023 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-37838726

RESUMO

Oryza coarctata (2n = 4X = 48, KKLL) is an allotetraploid, undomesticated relative of rice and the only species in the genus Oryza with tolerance to high salinity and submergence. Therefore, it contains important stress and tolerance genes/factors for rice. The initial draft genome published was limited by data and technical restrictions, leading to an incomplete and highly fragmented assembly. This study reports a new, highly contiguous chromosome-level genome assembly and annotation of O. coarctata. PacBio high-quality HiFi reads generated 460 contigs with a total length of 573.4 Mb and an N50 of 23.1 Mb, which were assembled into scaffolds with Hi-C data, anchoring 96.99% of the assembly onto 24 chromosomes. The genome assembly comprises 45,571 genes, and repetitive content contributes 25.5% of the genome. This study provides the novel identification of the KK and LL genome types of the genus Oryza, leading to valuable insights into rice genome evolution. The chromosome-level genome assembly of O. coarctata is a valuable resource for rice research and molecular breeding.


Assuntos
Genoma de Planta , Oryza , Cromossomos , Oryza/genética , Filogenia , Salinidade
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