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1.
Neuroimage ; : 120789, 2024 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-39159702

RESUMO

Interpersonal emotion regulation (IER) is a crucial ability for effectively recovering from negative emotions through social interaction. It has been emphasized that the empathy network, cognitive control network, and affective generation network sustain the deployment of IER. However, the temporal dynamics of functional connectivity among these networks of IER remains unclear. This study utilized IER task-fMRI and sliding window approach to examine both the stationary and dynamic functional connectivity (dFC) of IER. Fifty-five healthy participants were recruited for the present study. Through clustering analysis, four distinct brain states were identified in dFC. State 1 demonstrated situation modification stage of IER, with strong connectivity between affective generation and visual networks. State 2 exhibited pronounced connectivity between empathy network and both cognitive control and affective generation networks, reflecting the empathy stage of IER. Next, a 'top-down' pattern is observed between the connectivity of cognitive control and affective generation networks during the cognitive control stage of state 3. The affective response modulation stage of state 4 mainly involved connections between empathy and affective generation networks. Specifically, the degree centrality of the left middle temporal gyrus (MTG) mediated the association between one's IER tendency and the regulatory effects in state 2. The betweenness centrality of the left ventrolateral prefrontal cortex (VLPFC) mediated the association between one's IER efficiency and the regulatory effects in state 3. Altogether, these findings revealed that dynamic connectivity transitions among empathy, cognitive control, and affective generation networks, with the left VLPFC and MTG playing dominant roles, evident across the IER processing.

2.
Biochem Biophys Res Commun ; 737: 150502, 2024 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-39180962

RESUMO

Ribosome biogenesis is a highly regulated multistep process aided by energy-consuming auxiliary factors. GTPases form the largest class of auxiliary factors used by bacterial, cytosolic, and mitochondrial ribosomes for their maturation. Mtg3, a circularly permuted YqeH family of GTPase, is implicated in the mitoribosome small subunit biogenesis. However, its precise mechanistic role has yet to be characterized. Mtg3 is likely to bind precursor mitoribosome molecules during subunit maturation in vivo. However, this interaction has yet to be observed with mitoribosomes biochemically. In this study, we delineate the specific conditions necessary for preserving the association of Mtg3 with mitoribosomes on a sucrose density gradient. We show that the C-terminal domain of Mtg3 is required for robust binding to the mitoribosome. Furthermore, point mutants likely to abrogate GTP/GDP binding and GTPase activity compromise protein function in vivo. Surprisingly, the association with the mitoribosome was not compromised in mutants likely to be deficient for nucleotide binding/hydrolysis. Thus, our finding supports a model wherein Mtg3 binds to a precursor mitoribosome through its C-terminus to facilitate a conformational change or validate a folding intermediate driven by the GTP/GDP binding and hydrolysis cycle.

3.
Cryobiology ; 111: 142-145, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37001845

RESUMO

The CryoPreservation Media (CPM) for mouse sperm using raffinose and skim milk have been improved by adding either monothioglycerol (MTG) or l-glutamine to reduce the oxidative damage during sperm freezing and thawing. The CARD-CPM utilizing l-glutamine, but not MTG, has been widely used to meet the rising demand for cryopreservation of genetically modified mice, as the CARD method also improved sperm capacitation and in vitro fertilization (IVF). However, the viability of sperm frozen in the CARD-CPM is highly variable, indicating a room for improvement. To develop a more dependable technique for mouse sperm cryopreservation, we investigate whether combining MTG and l-glutamine in the CPM (MG-CPM) can produce a synergistic impact on sperm thawing and IVF rate. We found that MG-CPM reduced the incidence of infertility and increased the IVF success rate. Therefore, cryopreservation of mouse sperm in MG-CPM is a reliable method to ensure embryo generation from frozen sperm.


Assuntos
Criopreservação , Glutamina , Camundongos , Masculino , Animais , Criopreservação/métodos , Glutamina/farmacologia , Crioprotetores/farmacologia , Camundongos Endogâmicos C57BL , Sêmen , Espermatozoides
4.
Histopathology ; 81(6): 841-846, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36177509

RESUMO

Angiomyofibroblastoma (AMF), a rare benign vulvovaginal mesenchymal tumour, poses a diagnostic challenge due to histologic and immunohistochemical overlap with other vulvar mesenchymal tumours. Recently, MTG1-CYP2E1 fusion transcripts were reported in 5/5 AMFs; no other genetic alterations have been described to date. Herein, we sought to investigate the frequency of the MTG1-CYP2E1 fusion and the presence of other potential genetic alterations in a cohort of AMFs (n = 7, patient age range: 28-49 years). Tumours demonstrated classic morphologic features including alternating hypo/hypercellular areas, capillary channels surrounded by epithelioid/spindled tumour cells, and variable amounts of mature adipose tissue. reverse transcription-polymerase chain reaction (RT-PCR) for MTG1-CYP2E1 fusion, performed in all seven cases, showed the fusion transcript in five of six cases (one case with technical failure). Two tumours, including the one lacking the fusion, were subjected to targeted next-generation sequencing (104 genes) and a sarcoma fusion assay (28 genes); the fusion negative AMF also underwent RNA sequencing. No additional mutations, copy number alterations, or fusion genes were identified with the assays employed. We conclude that the majority of AMFs harbour recurrent MTG1-CYP2E1 fusion transcripts and identification of this fusion may aid in the diagnosis.


Assuntos
Sarcoma , Neoplasias de Tecidos Moles , Neoplasias Vulvares , Adulto , Feminino , Humanos , Pessoa de Meia-Idade , Citocromo P-450 CYP2E1/genética , Sarcoma/genética , Análise de Sequência de RNA , Neoplasias de Tecidos Moles/genética , Neoplasias Vulvares/patologia , Recidiva
5.
J Biol Chem ; 295(44): 14866-14877, 2020 10 30.
Artigo em Inglês | MEDLINE | ID: mdl-32817168

RESUMO

Group 2 innate lymphoid cells (ILC2s) represent a subset of newly discovered immune cells that are involved in immune reactions against microbial pathogens, host allergic reactions, as well as tissue repair. The basic helix-loop-helix transcription factors collectively called E proteins powerfully suppress the differentiation of ILC2s from bone marrow and thymic progenitors while promoting the development of B and T lymphocytes. How E proteins exert the suppression is not well understood. Here we investigated the underlying molecular mechanisms using inducible gain and loss of function approaches in ILC2s and their precursors, respectively. Cross-examination of RNA-seq and ATAC sequencing data obtained at different time points reveals a set of genes that are likely direct targets of E proteins. Consequently, a widespread down-regulation of chromatin accessibility occurs at a later time point, possibly due to the activation of transcriptional repressor genes such as Cbfa2t3 and Jdp2 The large number of genes repressed by gain of E protein function leads to the down-regulation of a transcriptional network important for ILC2 differentiation.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Diferenciação Celular , Redes Reguladoras de Genes , Imunidade Inata , Linfócitos/metabolismo , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Linhagem Celular , Cromatina/metabolismo , Expressão Gênica , Linfócitos/citologia , Linfócitos/imunologia , Camundongos
6.
Anal Biochem ; 592: 113584, 2020 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-31953047

RESUMO

Celiac disease (CD) is a chronic immune-mediated disease in which gluten ingestion leads to damage of the small intestinal mucosa in genetically susceptible individuals. The enteropathy is mainly induced by the production of IFN-γ from intestinal CD4+T cells that recognise gliadin peptides following deamidation by tissue transglutaminase. The only available therapy is a strict, lifelong gluten-free diet (GFD). This diet is strongly demanding for patients, which justifies the search for alternative strategies. The enzyme approach is one promising strategy to address this issue. In particular, transamidation of wheat gliadin by microbial transglutaminase (mTG) was fully effective at inhibiting gliadin-specific IFN-γ secretion in intestinal T cells from CD patients. Furthermore, transamidated gliadin induced higher levels of the anti-inflammatory IL-10 than native gliadin in different in vitro models. These data suggest that a more balanced immune response could be induced by mTG-treated gliadin in the small intestine of celiac patients. Furthermore, the highlighted biological property of mTG-treated gliadin could be exploited to induce tolerance to native gliadin in at-risk individuals.


Assuntos
Linfócitos T CD4-Positivos/efeitos dos fármacos , Doença Celíaca/tratamento farmacológico , Gliadina/metabolismo , Mucosa Intestinal/efeitos dos fármacos , Transglutaminases , Triticum , Bactérias/enzimologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/patologia , Farinha , Humanos , Interleucina-10/metabolismo , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Transglutaminases/farmacologia , Transglutaminases/uso terapêutico , Triticum/efeitos dos fármacos , Triticum/metabolismo
7.
Neurosurg Focus ; 48(2): E7, 2020 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-32006945

RESUMO

OBJECTIVE: The functional importance of the superior temporal lobe at the level of Heschl's gyrus is well known. However, the organization and function of these cortical areas and the underlying fiber tracts connecting them remain unclear. The goal of this study was to analyze the area formed by the organization of the intersection of Heschl's gyrus-related fiber tracts, which the authors have termed the "Heschl's gyrus fiber intersection area" (HGFIA). METHODS: The subcortical connectivity of Heschl's gyrus tracts was analyzed by white matter fiber dissection and by diffusion tensor imaging tractography. The white matter tracts organized in relation to Heschl's gyrus were isolated in 8 human hemispheres from cadaveric specimens and in 8 MRI studies in 4 healthy volunteers. In addition, these tracts and their functions were described in the surgical cases of left temporal gliomas next to the HGFIA in 6 patients who were awake during surgery and underwent intraoperative electrical stimulation mapping. RESULTS: Five tracts were observed to pass through the HGFIA: the anterior segment of the arcuate fasciculus, the middle longitudinal fasciculus, the acoustic radiation, the inferior fronto-occipital fasciculus, and the optic radiation. In addition, U fibers originating at the level of Heschl's gyrus and heading toward the middle temporal gyrus were identified. CONCLUSIONS: This investigation of the HGFIA, a region where 5 fiber tracts intersect in a relationship with the primary auditory area, provides new insights into the subcortical organization of Wernicke's area. This information is valuable when a temporal surgical approach is planned, in order to assess the surgical risk related to language disturbances.


Assuntos
Córtex Auditivo/diagnóstico por imagem , Córtex Auditivo/fisiologia , Vias Auditivas/diagnóstico por imagem , Vias Auditivas/fisiologia , Percepção Auditiva/fisiologia , Idioma , Adulto , Idoso , Idoso de 80 Anos ou mais , Córtex Auditivo/anatomia & histologia , Vias Auditivas/anatomia & histologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fibras Nervosas/fisiologia , Vias Neurais/diagnóstico por imagem , Vias Neurais/fisiologia
8.
Neuroimage ; 203: 116199, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31536804

RESUMO

Valence is a dimension of emotion and can be either positive, negative, or neutral. Valences can be expressed through the visual and auditory modalities, and the valences of each modality can be conveyed by different types of stimuli (face, body, voice or music). This study focused on the modality-general representations of valences, that is, valence information can be shared across not only visual and auditory modalities but also different types of stimuli within each modality. Functional magnetic resonance imaging (fMRI) data were collected when subjects made affective judgment on silent videos (face and body) and audio clips (voice and music). The searchlight analysis helped to locate four areas that might be sensitive to the representations of modality-general valences, including the bilateral postcentral gyrus, left middle temporal gyrus (MTG) and right middle frontal gyrus (MFG). Further cross-modal classification based on multivoxel pattern analysis (MVPA) was performed as a validation analysis, which suggested that only the left postcentral gyrus could successfully distinguish three valences (positive versus negative and versus neutral: PvsNvs0) across different types of stimuli (face, body, voice or music), and the classification was also successful in left MTG across the stimuli types of face and body. The univariate analysis further found the valence-specific activation differences across stimulus types in MTG. Our study showed that the left postcentral gyrus was informative to valence representations, and extended the research about valence representation that the modality-general representation of valences across not only visual and auditory modalities but also different types of stimuli within each modality.


Assuntos
Percepção Auditiva/fisiologia , Encéfalo/fisiologia , Emoções/fisiologia , Percepção Visual/fisiologia , Estimulação Acústica , Adulto , Mapeamento Encefálico , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Estimulação Luminosa , Adulto Jovem
9.
Neuroimage ; 132: 129-137, 2016 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-26892858

RESUMO

During public addresses, speakers accompany their discourse with spontaneous hand gestures (beats) that are tightly synchronized with the prosodic contour of the discourse. It has been proposed that speech and beat gestures originate from a common underlying linguistic process whereby both speech prosody and beats serve to emphasize relevant information. We hypothesized that breaking the consistency between beats and prosody by temporal desynchronization, would modulate activity of brain areas sensitive to speech-gesture integration. To this aim, we measured BOLD responses as participants watched a natural discourse where the speaker used beat gestures. In order to identify brain areas specifically involved in processing hand gestures with communicative intention, beat synchrony was evaluated against arbitrary visual cues bearing equivalent rhythmic and spatial properties as the gestures. Our results revealed that left MTG and IFG were specifically sensitive to speech synchronized with beats, compared to the arbitrary vision-speech pairing. Our results suggest that listeners confer beats a function of visual prosody, complementary to the prosodic structure of speech. We conclude that the emphasizing function of beat gestures in speech perception is instantiated through a specialized brain network sensitive to the communicative intent conveyed by a speaker with his/her hands.


Assuntos
Lobo Frontal/fisiologia , Gestos , Linguística , Percepção da Fala/fisiologia , Lobo Temporal/fisiologia , Percepção Visual/fisiologia , Adulto , Encéfalo/fisiologia , Sinais (Psicologia) , Feminino , Mãos , Humanos , Imageamento por Ressonância Magnética , Masculino , Adulto Jovem
10.
J Clin Immunol ; 36 Suppl 1: 100-7, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-27003914

RESUMO

Antibody drug conjugates (ADCs), a promising class of cancer biopharmaceuticals, combine the specificity of therapeutic antibodies with the pharmacological potency of chemical, cytotoxic drugs. Ever since the first ADCs on the market, a plethora of novel ADC technologies has emerged, covering as diverse aspects as antibody engineering, chemical linker optimization and novel conjugation strategies, together aiming at constantly widening the therapeutic window for ADCs. This review primarily focuses on novel chemical and biotechnological strategies for the site-directed attachment of drugs that are currently validated for 2nd generation ADCs to promote conjugate homogeneity and overall stability.


Assuntos
Biotecnologia , Imunoconjugados , Aminoácidos/química , Animais , Biotecnologia/métodos , Biotecnologia/tendências , Dissulfetos/química , Humanos , Imunoconjugados/química , Imunoconjugados/genética , Terapia de Alvo Molecular/tendências
11.
Am J Physiol Gastrointest Liver Physiol ; 308(6): G562-71, 2015 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-25573176

RESUMO

Myeloid translocation genes (MTGs) are transcriptional corepressors implicated in development, malignancy, differentiation, and stem cell function. While MTG16 loss renders mice sensitive to chemical colitis, the role of MTG16 in the small intestine is unknown. Histological examination revealed that Mtg16(-/-) mice have increased enterocyte proliferation and goblet cell deficiency. After exposure to radiation, Mtg16(-/-) mice exhibited increased crypt viability and decreased apoptosis compared with wild-type (WT) mice. Flow cytometric and immunofluorescence analysis of intestinal epithelial cells for phospho-histone H2A.X also indicated decreased DNA damage and apoptosis in Mtg16(-/-) intestines. To determine if Mtg16 deletion affected epithelial cells in a cell-autonomous fashion, intestinal crypts were isolated from Mtg16(-/-) mice. Mtg16(-/-) and WT intestinal crypts showed similar enterosphere forming efficiencies when cultured in the presence of EGF, Noggin, and R-spondin. However, when Mtg16(-/-) crypts were cultured in the presence of Wnt3a, they demonstrated higher enterosphere forming efficiencies and delayed progression to mature enteroids. Mtg16(-/-) intestinal crypts isolated from irradiated mice exhibited increased survival compared with WT intestinal crypts. Interestingly, Mtg16 expression was reduced in a stem cell-enriched population at the time of crypt regeneration. This is consistent with MTG16 negatively regulating regeneration in vivo. Taken together, our data demonstrate that MTG16 loss promotes radioresistance and impacts intestinal stem cell function, possibly due to shifting cellular response away from DNA damage-induced apoptosis and towards DNA repair after injury.


Assuntos
Proliferação de Células , Raios gama , Mucosa Intestinal/metabolismo , Intestino Delgado/metabolismo , Proteínas Nucleares/metabolismo , Lesões Experimentais por Radiação/metabolismo , Regeneração , Fatores de Transcrição/metabolismo , Animais , Apoptose , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular , Dano ao DNA , Feminino , Regulação da Expressão Gênica , Células Caliciformes/metabolismo , Células Caliciformes/patologia , Histonas/metabolismo , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/patologia , Intestino Delgado/efeitos dos fármacos , Intestino Delgado/patologia , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas Nucleares/deficiência , Proteínas Nucleares/genética , Fenótipo , Lesões Experimentais por Radiação/etiologia , Lesões Experimentais por Radiação/patologia , Tolerância a Radiação , Regeneração/efeitos dos fármacos , Proteínas Repressoras , Transdução de Sinais , Células-Tronco/metabolismo , Células-Tronco/patologia , Técnicas de Cultura de Tecidos , Fatores de Transcrição/deficiência , Fatores de Transcrição/genética , Proteína Wnt3A/farmacologia
12.
J Sleep Res ; 24(5): 576-82, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25871325

RESUMO

The story-like organization of dreams is characterized by a pervasive bizarreness of events and actions that resembles psychotic thought, and largely exceeds that observed in normal waking fantasies. Little is known about the neural correlates of the confabulatory narrative construction of dreams. In this study, dreams, fantasies elicited by ambiguous pictorial stimuli, and non-imaginative first- and third-person narratives from healthy participants were recorded, and were then studied for brain blood oxygen level-dependent functional magnetic resonance imaging on a 3.0-Tesla scanner while listening to their own narrative reports and attempting a retrieval of the corresponding experience. In respect to non-bizarre reports of daytime activities, the script-driven recall of dreams and fantasies differentially activated a right hemisphere network including areas in the inferior frontal gyrus, and superior and middle temporal gyrus. Neural responses were significantly greater for fantasies than for dreams in all regions, and inversely proportional to the degree of bizarreness observed in narrative reports. The inferior frontal gyrus, superior and middle temporal gyrus have been implicated in the semantic activation, integration and selection needed to build a coherent story representation and to resolve semantic ambiguities; in deductive and inferential reasoning; in self- and other-perspective taking, theory of mind, moral and autobiographical reasoning. Their degree of activation could parallel the level of logical robustness or inconsistency experienced when integrating information and mental representations in the process of building fantasy and dream narratives.


Assuntos
Encéfalo/anatomia & histologia , Encéfalo/citologia , Sonhos , Fantasia , Rememoração Mental/fisiologia , Neurônios/fisiologia , Adulto , Percepção Auditiva , Encéfalo/fisiologia , Mapeamento Encefálico , Sonhos/psicologia , Feminino , Humanos , Lógica , Imageamento por Ressonância Magnética , Masculino , Narração , Estimulação Luminosa , Autorrelato , Semântica
13.
J Mol Cell Cardiol ; 67: 26-37, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24362314

RESUMO

Myocardial ischemia/reperfusion (I/R) injury is a major clinical problem leading to cardiac dysfunction and myocyte death. It is widely held that I/R causes damage to membrane phospholipids, and is a significant mechanism of cardiac I/R injury. Molecular dissection of sarcolemmal damage in I/R, however, has been difficult to address experimentally. We studied here cardiac I/R injury under conditions targeting gain- or loss-of sarcolemma integrity. To implement gain-in-sarcolemma integrity during I/R, synthetic copolymer-based sarcolemmal stabilizers (CSS), including Poloxamer 188 (P188), were used as a tool to directly stabilize the sarcolemma. Consistent with the hypothesis of sarcolemmal stabilization, cellular markers of necrosis and apoptosis evident in untreated myocytes were fully blocked in sarcolemma stabilized myocytes. Unexpectedly, sarcolemmal stabilization of adult cardiac myocytes did not affect the status of myocyte-generated oxidants or lipid peroxidation in two independent assays. We also investigated the loss of sarcolemmal integrity using two independent genetic mouse models, dystrophin-deficient mdx or dysferlin knockout (Dysf KO) mice. Both models of sarcolemmal loss-of-function were severely affected by I/R injury ex vivo, and this was lessened by CSS. In vivo studies also showed that infarct size was significantly reduced in CSS-treated hearts. Mechanistically, these findings support a model whereby I/R-mediated increased myocyte oxidative stress is uncoupled from myocyte injury. Because the sarcolemma stabilizers used here do not transit across the myocyte membrane this is evidence that intracellular targets of oxidants are not sufficiently altered to affect cell death when sarcolemma integrity is preserved by synthetic stabilizers. These findings, in turn, suggest that sarcolemma destabilization, and consequent Ca(2+) mishandling, as a focal initiating mechanism underlying myocardial I/R injury.


Assuntos
Traumatismo por Reperfusão Miocárdica/prevenção & controle , Miócitos Cardíacos/patologia , Estresse Oxidativo , Sarcolema/metabolismo , Animais , Bioensaio , Caspase 3/metabolismo , Sobrevivência Celular , Células Cultivadas , Camundongos Endogâmicos C57BL , Modelos Cardiovasculares , Ratos
14.
Biochim Biophys Acta ; 1827(10): 1213-25, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23850549

RESUMO

Polyethylenimines (PEIs) are highly efficient non-viral transfectants, but can induce cell death through poorly understood necrotic and apoptotic processes as well as autophagy. Through high resolution respirometry studies in H1299 cells we demonstrate that the 25kDa branched polyethylenimine (25k-PEI-B), in a concentration and time-dependent manner, facilitates mitochondrial proton leak and inhibits the electron transport system. These events were associated with gradual reduction of the mitochondrial membrane potential and mitochondrial ATP synthesis. The intracellular ATP levels further declined as a consequence of PEI-mediated plasma membrane damage and subsequent ATP leakage to the extracellular medium. Studies with freshly isolated mouse liver mitochondria corroborated with bioenergetic findings and demonstrated parallel polycation concentration- and time-dependent changes in state 2 and state 4o oxygen flux as well as lowered ADP phosphorylation (state 3) and mitochondrial ATP synthesis. Polycation-mediated reduction of electron transport system activity was further demonstrated in 'broken mitochondria' (freeze-thawed mitochondrial preparations). Moreover, by using both high-resolution respirometry and spectrophotometry analysis of cytochrome c oxidase activity we were able to identify complex IV (cytochrome c oxidase) as a likely specific site of PEI mediated inhibition within the electron transport system. Unraveling the mechanisms of PEI-mediated mitochondrial energy crisis is central for combinatorial design of safer polymeric non-viral gene delivery systems.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/metabolismo , Respiração Celular/efeitos dos fármacos , Complexo de Proteínas da Cadeia de Transporte de Elétrons/metabolismo , Neoplasias Pulmonares/metabolismo , Mitocôndrias Hepáticas/metabolismo , Polietilenoimina/farmacologia , Prótons , Trifosfato de Adenosina/metabolismo , Animais , Carcinoma Pulmonar de Células não Pequenas/patologia , Morte Celular/efeitos dos fármacos , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Transporte de Elétrons/efeitos dos fármacos , Complexo de Proteínas da Cadeia de Transporte de Elétrons/antagonistas & inibidores , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Metabolismo Energético , Feminino , Humanos , Neoplasias Pulmonares/patologia , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Camundongos , Oxirredução , Fosforilação Oxidativa/efeitos dos fármacos , Consumo de Oxigênio/efeitos dos fármacos
15.
Neuroimage ; 84: 265-78, 2014 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-23962957

RESUMO

The complementary learning systems account of declarative memory suggests two distinct memory networks, a fast-mapping, episodic system involving the hippocampus, and a slower semantic memory system distributed across the neocortex in which new information is gradually integrated with existing representations. In this study, we investigated the extent to which these two networks are involved in the integration of novel words into the lexicon after extensive learning, and how the involvement of these networks changes after 24h. In particular, we explored whether having richer information at encoding influences the lexicalization trajectory. We trained participants with two sets of novel words, one where exposure was only to the words' phonological forms (the form-only condition), and one where pictures of unfamiliar objects were associated with the words' phonological forms (the picture-associated condition). A behavioral measure of lexical competition (indexing lexicalization) indicated stronger competition effects for the form-only words. Imaging (fMRI) results revealed greater involvement of phonological lexical processing areas immediately after training in the form-only condition, suggesting that tight connections were formed between novel words and existing lexical entries already at encoding. Retrieval of picture-associated novel words involved the episodic/hippocampal memory system more extensively. Although lexicalization was weaker in the picture-associated condition, overall memory strength was greater when tested after a 24hour delay, probably due to the availability of both episodic and lexical memory networks to aid retrieval. It appears that, during lexicalization of a novel word, the relative involvement of different memory networks differs according to the richness of the information about that word available at encoding.


Assuntos
Aprendizagem por Associação/fisiologia , Hipocampo/fisiologia , Memória Episódica , Neocórtex/fisiologia , Rede Nervosa/fisiologia , Semântica , Aprendizagem Verbal/fisiologia , Adolescente , Adulto , Mapeamento Encefálico , Feminino , Humanos , Masculino , Vias Neurais/fisiologia , Adulto Jovem
16.
Gut ; 62(10): 1446-55, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22833394

RESUMO

OBJECTIVE: The myeloid translocation genes (MTGs) are transcriptional corepressors with both Mtg8(-/-) and Mtgr1(-/-) mice showing developmental and/or differentiation defects in the intestine. We sought to determine the role of MTG16 in intestinal integrity. METHODS: Baseline and stress induced colonic phenotypes were examined in Mtg16(-/-) mice. To unmask phenotypes, we treated Mtg16(-/-) mice with dextran sodium sulphate (DSS) or infected them with Citrobacter rodentium and the colons were examined for ulceration and for changes in proliferation, apoptosis and inflammation. RESULTS: Mtg16(-/-) mice have altered immune subsets, suggesting priming towards Th1 responses. Mtg16(-/-) mice developed increased weight loss, diarrhoea, mortality and histological colitis and there were increased innate (Gr1(+), F4/80(+), CD11c(+) and MHCII(+); CD11c(+)) and Th1 adaptive (CD4) immune cells in Mtg16(-/-) colons after DSS treatment. Additionally, there was increased apoptosis and a compensatory increased proliferation in Mtg16(-/-) colons. Compared with wild-type mice, Mtg16(-/-) mice exhibited increased colonic CD4;IFN-γ cells in vehicle-treated and DSS-treated mice. Adoptive transfer of wild-type marrow into Mtg16(-/-) recipients did not rescue the Mtg16(-/-) injury phenotype. Isolated colonic epithelial cells from DSS-treated Mtg16(-/-) mice exhibited increased KC (Cxcl1) mRNA expression when compared with wild-type mice. Mtg16(-/-) mice infected with C rodentium had more severe colitis and greater bacterial colonisation. Last, MTG16 mRNA levels were reduced in human ulcerative colitis versus normal colon tissues. CONCLUSIONS: These observations indicate that MTG16 is critical for colonocyte survival and regeneration in response to intestinal injury and provide evidence that this transcriptional corepressor regulates inflammatory recruitment in response to injury.


Assuntos
Colite/patologia , Proteínas Nucleares/fisiologia , Fatores de Transcrição/fisiologia , Imunidade Adaptativa , Transferência Adotiva , Animais , Transplante Ósseo , Proliferação de Células , Colite/induzido quimicamente , Colite/imunologia , Colite/fisiopatologia , Colite Ulcerativa/metabolismo , Colo/imunologia , Sulfato de Dextrana , Enterócitos/patologia , Feminino , Humanos , Imunidade Inata , Imunofenotipagem , Absorção Intestinal/fisiologia , Mucosa Intestinal/patologia , Mucosa Intestinal/fisiopatologia , Masculino , Camundongos , Camundongos Knockout , Proteínas Nucleares/deficiência , Proteínas Nucleares/genética , Permeabilidade , Proteínas Repressoras , Células Th1/imunologia , Fatores de Transcrição/deficiência , Fatores de Transcrição/genética
17.
Artigo em Inglês | MEDLINE | ID: mdl-38387807

RESUMO

Procrastination has adverse consequences across cultural contexts. Behavioral research found a positive correlation between punishment sensitivity and procrastination. However, little is known about the neural substrates underlying the association between them. We employed voxel-based morphometry (VBM) and resting-state functional connectivity (RSFC) methods to address this issue with two independent samples. In Sample 1, behavioral results found that punishment sensitivity was positively related to procrastination. The VBM analysis showed that punishment sensitivity was negatively correlated with gray matter volume in left putamen. Subsequently, the RSFC results revealed that left putamen - left middle temporal gyrus (MTG) connectivity was positively associated with punishment sensitivity. More crucially, mediation analysis indicated that left putamen - left MTG connectivity mediated the relationship between punishment sensitivity and procrastination. The aforementioned results were validated in Sample 2. Altogether, left putamen - left MTG connectivity might be the neural signature of the association between punishment sensitivity and procrastination.


Assuntos
Mapeamento Encefálico , Procrastinação , Mapeamento Encefálico/métodos , Putamen/diagnóstico por imagem , Punição , Imageamento por Ressonância Magnética/métodos , Substância Cinzenta , Lobo Temporal/diagnóstico por imagem
18.
Cells ; 13(10)2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38786053

RESUMO

Peroxisome proliferator-activated receptor alpha (PPARA) is a ligand-activated transcription factor that is a key mediator of lipid metabolism and metabolic stress in the liver. Accumulating evidence shows that PPARA regulates the expression of various protein coding and non-coding genes that modulate metabolic stress in the liver. CBFA2/RUNX1 partner transcriptional co-repressor 3 (CBFA2T3) is a DNA-binding transcription factor that belongs to the myeloid translocation gene family. Many studies have shown that CBFA2T3 is associated with acute myeloid leukemia. Especially, CBFA2T3-GLIS2 fusion is a chimeric oncogene associated with a poor survival rate in pediatric acute megakaryocytic leukemia. A previous study identified that PPARA activation promoted Cbfa2t3 induction in liver and that Cbfa2t3 may have a modulatory role in metabolic stress. However, the effect of CBFA2T3 gene expression on metabolic stress is not understood. In this study, the PPARA ligand WY14643 activated Cbfa2t3 expression in mouse liver. Glucose tolerance test and insulin tolerance test data showed that insulin resistance is increased in Cbfa2t3-/- mice compared to Cbfa2t3+/+ mice. Hepatic CBFA2T3 modulates heat shock protein family A member 1b and carbonic anhydrase 5a expression. Histology analysis revealed lipid droplet and lipid accumulation in the liver of fasting Cbfa2t3-/- mice but not Cbfa2t3+/+ mice. The expression of lipid accumulation-related genes, such as Cd36, Cidea, and Fabp1, was increased in the liver of fasting Cbfa2t3-/- mice. Especially, basal expression levels of Cidea mRNA were elevated in the liver of Cbfa2t3-/- mice compared to Cbfa2t3+/+ mice. Much higher induction of Cidea mRNA was seen in the liver of Cbfa2t3-/- mice after WY14643 administration. These results indicate that hepatic CBFA2T3 is a PPARA-sensitive gene that may modulate metabolic stress in mouse liver.


Assuntos
Jejum , Metabolismo dos Lipídeos , Fígado , PPAR alfa , Animais , Metabolismo dos Lipídeos/genética , Fígado/metabolismo , Camundongos , PPAR alfa/metabolismo , PPAR alfa/genética , Masculino , Camundongos Endogâmicos C57BL , Resistência à Insulina , Camundongos Knockout , Pirimidinas/farmacologia
19.
Neuroimage ; 83: 937-50, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23872496

RESUMO

Functional connectivity (FC) as measured by correlation between fMRI BOLD time courses of distinct brain regions has revealed meaningful organization of spontaneous fluctuations in the resting brain. However, an increasing amount of evidence points to non-stationarity of FC; i.e., FC dynamically changes over time reflecting additional and rich information about brain organization, but representing new challenges for analysis and interpretation. Here, we propose a data-driven approach based on principal component analysis (PCA) to reveal hidden patterns of coherent FC dynamics across multiple subjects. We demonstrate the feasibility and relevance of this new approach by examining the differences in dynamic FC between 13 healthy control subjects and 15 minimally disabled relapse-remitting multiple sclerosis patients. We estimated whole-brain dynamic FC of regionally-averaged BOLD activity using sliding time windows. We then used PCA to identify FC patterns, termed "eigenconnectivities", that reflect meaningful patterns in FC fluctuations. We then assessed the contributions of these patterns to the dynamic FC at any given time point and identified a network of connections centered on the default-mode network with altered contribution in patients. Our results complement traditional stationary analyses, and reveal novel insights into brain connectivity dynamics and their modulation in a neurodegenerative disease.


Assuntos
Mapeamento Encefálico/métodos , Encéfalo/fisiologia , Esclerose Múltipla Recidivante-Remitente/fisiopatologia , Vias Neurais/fisiologia , Análise de Componente Principal , Descanso/fisiologia , Adulto , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino
20.
Open Life Sci ; 18(1): 20220737, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37791057

RESUMO

Microbial transglutaminases (mTGs) belong to the family of global TGs, isolated and characterised by various bacterial strains, with the first being Streptomyces mobaraensis. This literature review also discusses TGs of animal and plant origin. TGs catalyse the formation of an isopeptide bond, cross-linking the amino and acyl groups. Due to its broad enzymatic activity, TG is extensively utilised in the food industry. The annual net growth in the utilisation of enzymes in the food processing industry is estimated to be 21.9%. As of 2020, the global food enzymes market was valued at around $2.3 billion USD (mTG market was estimated to be around $200 million USD). Much of this growth is attributed to the applications of mTG, benefiting both producers and consumers. In the food industry, TG enhances gelation and modifies emulsification, foaming, viscosity, and water-holding capacity. Research on TG, mainly mTG, provides increasing insights into the wide range of applications of this enzyme in various industrial sectors and promotes enzymatic processing. This work presents the characteristics of TGs, their properties, and the rationale for their utilisation. The review aims to provide theoretical foundations that will assist researchers worldwide in building a methodological framework and furthering the advancement of biotechnology research.

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