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1.
PLoS Biol ; 21(11): e3002386, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37983249

RESUMO

Defensive responses to visually threatening stimuli represent an essential fear-related survival instinct, widely detected across species. The neural circuitry mediating visually triggered defensive responses has been delineated in the midbrain. However, the molecular mechanisms regulating the development and function of these circuits remain unresolved. Here, we show that midbrain-specific deletion of the transcription factor Brn3b causes a loss of neurons projecting to the lateral posterior nucleus of the thalamus. Brn3b deletion also down-regulates the expression of the neuropeptide tachykinin 2 (Tac2). Furthermore, Brn3b mutant mice display impaired defensive freezing responses to visual threat precipitated by social isolation. This behavioral phenotype could be ameliorated by overexpressing Tac2, suggesting that Tac2 acts downstream of Brn3b in regulating defensive responses to threat. Together, our experiments identify specific genetic components critical for the functional organization of midbrain fear-related visual circuits. Similar mechanisms may contribute to the development and function of additional long-range brain circuits underlying fear-associated behavior.


Assuntos
Medo , Mesencéfalo , Animais , Camundongos , Medo/fisiologia , Mesencéfalo/fisiologia , Neurônios/fisiologia , Tálamo
2.
Development ; 146(14)2019 07 22.
Artigo em Inglês | MEDLINE | ID: mdl-31332038

RESUMO

Developmental control of long-range neuronal connections in the mammalian midbrain remains unclear. We explored the mechanisms regulating target selection of the developing superior colliculus (SC). The SC is a midbrain center that directs orienting behaviors and defense responses. We discovered that a transcription factor, Rorß, controls establishment of axonal projections from the SC to two thalamic nuclei: the dorsal lateral geniculate nucleus (dLGN) and the lateral posterior nucleus (LP). A genetic strategy used to visualize SC circuits revealed that in control animals Rorß+ neurons abundantly innervate the dLGN but barely innervate the LP. The opposite phenotype was observed in global and conditional Rorb mutants: projections to the dLGN were strongly decreased, and projections to the LP were increased. Furthermore, overexpression of Rorb in the wild type showed increased projections to the dLGN and decreased projections to the LP. In summary, we identified Rorß as a key developmental mediator of colliculo-thalamic innervation. Such regulation could represent a general mechanism orchestrating long-range neuronal connections in the mammalian brain.


Assuntos
Axônios/fisiologia , Mesencéfalo/embriologia , Mesencéfalo/crescimento & desenvolvimento , Neurônios/metabolismo , Membro 2 do Grupo F da Subfamília 1 de Receptores Nucleares/fisiologia , Vias Visuais/metabolismo , Animais , Animais Recém-Nascidos , Embrião de Mamíferos , Feminino , Corpos Geniculados/fisiologia , Células HEK293 , Humanos , Masculino , Mesencéfalo/citologia , Camundongos , Camundongos Transgênicos , Membro 2 do Grupo F da Subfamília 1 de Receptores Nucleares/genética , Membro 2 do Grupo F da Subfamília 1 de Receptores Nucleares/metabolismo , Gravidez , Colículos Superiores/fisiologia
3.
J Neurosci ; 38(15): 3753-3766, 2018 04 11.
Artigo em Inglês | MEDLINE | ID: mdl-29572434

RESUMO

Inhibitory interneurons sculpt the outputs of excitatory circuits to expand the dynamic range of information processing. In mammalian retina, >30 types of amacrine cells provide lateral inhibition to vertical, excitatory bipolar cell circuits, but functional roles for only a few amacrine cells are well established. Here, we elucidate the function of corticotropin-releasing hormone (CRH)-expressing amacrine cells labeled in Cre-transgenic mice of either sex. CRH cells costratify with the ON alpha ganglion cell, a neuron highly sensitive to positive contrast. Electrophysiological and optogenetic analyses demonstrate that two CRH types (CRH-1 and CRH-3) make GABAergic synapses with ON alpha cells. CRH-1 cells signal via graded membrane potential changes, whereas CRH-3 cells fire action potentials. Both types show sustained ON-type responses to positive contrast over a range of stimulus conditions. Optogenetic control of transmission at CRH-1 synapses demonstrates that these synapses are tuned to low temporal frequencies, maintaining GABA release during fast hyperpolarizations during brief periods of negative contrast. CRH amacrine cell output is suppressed by prolonged negative contrast, when ON alpha ganglion cells continue to receive inhibitory input from converging OFF-pathway amacrine cells; the converging ON- and OFF-pathway inhibition balances tonic excitatory drive to ON alpha cells. Previously, it was demonstrated that CRH-1 cells inhibit firing by suppressed-by-contrast (SbC) ganglion cells during positive contrast. Therefore, divergent outputs of CRH-1 cells inhibit two ganglion cell types with opposite responses to positive contrast. The opposing responses of ON alpha and SbC ganglion cells are explained by differing excitation/inhibition balance in the two circuits.SIGNIFICANCE STATEMENT A goal of neuroscience research is to explain the function of neural circuits at the level of specific cell types. Here, we studied the function of specific types of inhibitory interneurons, corticotropin-releasing hormone (CRH) amacrine cells, in the mouse retina. Genetic tools were used to identify and manipulate CRH cells, which make GABAergic synapses with a well studied ganglion cell type, the ON alpha cell. CRH cells converge with other types of amacrine cells to tonically inhibit ON alpha cells and balance their high level of excitation. CRH cells diverge to different types of ganglion cell, the unique properties of which depend on their balance of excitation and inhibition.


Assuntos
Células Amácrinas/fisiologia , Hormônio Liberador da Corticotropina/metabolismo , Vias Visuais/citologia , Potenciais de Ação , Células Amácrinas/metabolismo , Animais , Feminino , Neurônios GABAérgicos/metabolismo , Neurônios GABAérgicos/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Células Ganglionares da Retina/metabolismo , Células Ganglionares da Retina/fisiologia , Potenciais Sinápticos , Vias Visuais/fisiologia
4.
Circ J ; 82(12): 2962-2969, 2018 11 24.
Artigo em Inglês | MEDLINE | ID: mdl-30259899

RESUMO

BACKGROUND: The relationship between anemia and sudden cardiac arrest (SCA) is unclear in the general population, so we assessed it in a nationwide cohort.Methods and Results: We studied 494,948 subjects (mean age, 47.8 years; 245,333 men [49.6%]) with national health check-up data from the Korean National Health Insurance Database Cohort. During a mean follow-up period of 5.4 years, SCA occurred in 616 participants (396 men, 220 women). The incidence rates of SCA increased across the 4 anemia groups in both men (0.3, 1.5, 5.3, and 4.5 per 1,000 person-years) and women (0.2, 0.5, 0.5, and 1.2 per 1,000 person-years). The SCA risk per 1-unit decrease in hemoglobin (Hb) increased by 21% and 24%, respectively, in multivariable models adjusted for cardiovascular factors, in men (95% confidence interval [CI], 13-29%; P<0.001) and women (95% CI, 13-37%; P<0.001). A negative correlation between QTc interval and Hb level was observed in men, and a trend was observed in women. CONCLUSIONS: Anemia was associated with an increased risk of SCA even after accounting for concomitant conditions in a South Korean nationwide cohort. The correlation between anemia and SCA might be explained by an increase in arrhythmic risks, such as QTc prolongation.


Assuntos
Anemia/mortalidade , Morte Súbita Cardíaca/etiologia , Adulto , Idoso , Feminino , Seguimentos , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , República da Coreia/epidemiologia , Fatores de Risco , Fatores Sexuais
5.
J Neurosci ; 35(30): 10685-700, 2015 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-26224854

RESUMO

Visual processing in the retina depends on coordinated signaling by interneurons. Photoreceptor signals are relayed to ∼20 ganglion cell types through a dozen excitatory bipolar interneurons, each responsive to light increments (ON) or decrements (OFF). ON and OFF bipolar cell pathways become tuned through specific connections with inhibitory interneurons: horizontal and amacrine cells. A major obstacle for understanding retinal circuitry is the unknown function of most of the ∼30-40 amacrine cell types, each of which synapses onto a subset of bipolar cell terminals, ganglion cell dendrites, and other amacrine cells. Here, we used a transgenic mouse line in which vasoactive intestinal polypeptide-expressing (VIP+) GABAergic interneurons express Cre recombinase. Targeted whole-cell recordings of fluorescently labeled VIP+ cells revealed three predominant types: wide-field bistratified and narrow-field monostratified cells with somas in the inner nuclear layer (INL) and medium-field monostratified cells with somas in the ganglion cell layer (GCL). Bistratified INL cells integrated excitation and inhibition driven by both ON and OFF pathways with little spatial tuning. Narrow-field INL cells integrated excitation driven by the ON pathway and inhibition driven by both pathways, with pronounced hyperpolarizations at light offset. Monostratified GCL cells integrated excitation and inhibition driven by the ON pathway and showed center-surround spatial tuning. Optogenetic experiments showed that, collectively, VIP+ cells made strong connections with OFF δ, ON-OFF direction-selective, and W3 ganglion cells but weak, inconsistent connections with ON and OFF α cells. Revealing VIP+ cell morphologies, receptive fields and synaptic connections advances our understanding of their role in visual processing. SIGNIFICANCE STATEMENT: The retina is a model system for understanding nervous system function. At the first stage, rod and cone photoreceptors encode light and communicate with a complex network of interneurons. These interneurons drive the responses of ganglion cells, which form the optic nerve and transmit visual information to the brain. Presently, we lack information about many of the retina's inhibitory amacrine interneurons. In this study, we used genetically modified mice to study the light responses and intercellular connections of specific amacrine cell types. The results show diversity in the shape and function of the studied amacrine cells and elucidate their connections with specific types of ganglion cell. The findings advance our understanding of the cellular basis for retinal function.


Assuntos
Interneurônios/citologia , Interneurônios/fisiologia , Retina/citologia , Retina/fisiologia , Vias Visuais/citologia , Vias Visuais/fisiologia , Animais , Células Cultivadas , Feminino , Imuno-Histoquímica , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Microscopia Confocal , Optogenética , Técnicas de Patch-Clamp , Peptídeo Intestinal Vasoativo/biossíntese
6.
Geriatr Nurs ; 37(4): 292-5, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27168423

RESUMO

The objective of this study was to validate fork test which is a simple tool to assess the consistency of food. The consistencies of 27 water and thickener mixtures were measured with a viscometer. These measures were then compared to those obtained with fork test to evaluate the validity of fork test. The inter-observer and intra-observer reliabilities of the fork test were assessed with an intra-class correlation coefficient. The viscometer was used to obtain reference values for three categories (0-300 cP, 300-10,000 cP, and >10,000 cP) in order to categorize water and thickener mixtures into grade 1, grade 2, or grade 3 according to the results of fork test. Our results revealed that the fork test showed excellent validity (r = -0.889, p < 0.05), intra-observer reliability, and inter-observer reliability. Therefore, fork test may be used as a practical tool to assess food consistency.


Assuntos
Transtornos de Deglutição/dietoterapia , Dieta/métodos , Viscosidade , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Reprodutibilidade dos Testes
7.
J Neurosci ; 34(11): 3976-81, 2014 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-24623775

RESUMO

Direction selectivity represents a fundamental visual computation. In mammalian retina, On-Off direction-selective ganglion cells (DSGCs) respond strongly to motion in a preferred direction and weakly to motion in the opposite, null direction. Electrical recordings suggested three direction-selective (DS) synaptic mechanisms: DS GABA release during null-direction motion from starburst amacrine cells (SACs) and DS acetylcholine and glutamate release during preferred direction motion from SACs and bipolar cells. However, evidence for DS acetylcholine and glutamate release has been inconsistent and at least one bipolar cell type that contacts another DSGC (On-type) lacks DS release. Here, whole-cell recordings in mouse retina showed that cholinergic input to On-Off DSGCs lacked DS, whereas the remaining (glutamatergic) input showed apparent DS. Fluorescence measurements with the glutamate biosensor intensity-based glutamate-sensing fluorescent reporter (iGluSnFR) conditionally expressed in On-Off DSGCs showed that glutamate release in both On- and Off-layer dendrites lacked DS, whereas simultaneously recorded excitatory currents showed apparent DS. With GABA-A receptors blocked, both iGluSnFR signals and excitatory currents lacked DS. Our measurements rule out DS release from bipolar cells onto On-Off DSGCs and support a theoretical model suggesting that apparent DS excitation in voltage-clamp recordings results from inadequate voltage control of DSGC dendrites during null-direction inhibition. SAC GABA release is the apparent sole source of DS input onto On-Off DSGCs.


Assuntos
Potenciais de Ação/fisiologia , Ácido Glutâmico/metabolismo , Células Bipolares da Retina/fisiologia , Células Ganglionares da Retina/fisiologia , Sinapses/fisiologia , Transmissão Sináptica/fisiologia , Acetilcolina/metabolismo , Células Amácrinas/fisiologia , Animais , Dendritos/fisiologia , Feminino , Corantes Fluorescentes , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Microscopia de Fluorescência , Modelos Neurológicos , Ácido gama-Aminobutírico/metabolismo
8.
J Biomed Sci ; 22: 73, 2015 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-26362652

RESUMO

BACKGROUND: Adiponectin levels have been shown to be associated with colorectal cancer (CRC). Furthermore, a newly identified adiponectin receptor, T-cadherin, has been associated with plasma adiponectin levels. Therefore, we investigated the potential for a genetic association between T-cadherin and CRC risk. RESULT: We conducted a case-control study using the Korean Cancer Prevention study-II cohort, which is composed of 325 CRC patients and 977 normal individuals. Study results revealed that rs3865188 in the 5' flanking region of the T-cadherin gene (CDH13) was significantly associated with CRC (p = 0.0474). The odds ratio (OR) for the TT genotype as compared to the TA + AA genotype was 1.577 (p = 0.0144). In addition, the interaction between CDH13 and the adiponectin gene (APN) for CRC risk was investigated using a logistic regression analysis. Among six APN single nucleotide polymorphisms (rs182052, rs17366568, rs2241767, rs3821799, rs3774261, and rs6773957), an interaction with the rs3865188 was found for four (rs2241767, rs3821799, rs3774261, and rs6773957). The group with combined genotypes of TT for rs3865188 and GG for rs377426 displayed the highest risk for CRC development as compared to those with the other genotype combinations. The OR for the TT/GG genotype as compared to the AA/AA genotype was 4.108 (p = 0.004). Furthermore, the plasma adiponectin level showed a correlation with the gene-gene interaction, and the group with the highest risk for CRC had the lowest adiponectin level (median, 4.8 µg/mL for the TT/GG genotype vs.7.835 µg/mL for the AA/AA genotype, p = 0.0017). CONCLUSIONS: The present study identified a new genetic factor for CRC risk and an interaction between CDH13 and APN in CRC risk. These genetic factors may be useful for predicting CRC risk.


Assuntos
Adiponectina/genética , Caderinas/genética , Neoplasias Colorretais/genética , Epistasia Genética , Proteínas de Neoplasias/genética , Polimorfismo de Nucleotídeo Único , Adulto , Feminino , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco
9.
Proc Natl Acad Sci U S A ; 109(36): E2391-8, 2012 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-22891316

RESUMO

The retina reports the visual scene to the brain through many parallel channels, each carried by a distinct population of retinal ganglion cells. Among these, the population with the smallest and densest receptive fields encodes the neural image with highest resolution. In human retina, and those of cat and macaque, these high-resolution ganglion cells act as generic pixel encoders: They serve to represent many different visual inputs and convey a neural image of the scene downstream for further processing. Here we identify and analyze high-resolution ganglion cells in the mouse retina, using a transgenic line in which these cells, called "W3", are labeled fluorescently. Counter to the expectation, these ganglion cells do not participate in encoding generic visual scenes, but remain silent during most common visual stimuli. A detailed study of their response properties showed that W3 cells pool rectified excitation from both On and Off bipolar cells, which makes them sensitive to local motion. However, they also receive unusually strong lateral inhibition, both pre- and postsynaptically, triggered by distant motion. As a result, the W3 cell can detect small moving objects down to the receptive field size of bipolar cells, but only if the background is featureless or stationary--an unusual condition. A survey of naturalistic stimuli shows that W3 cells may serve as alarm neurons for overhead predators.


Assuntos
Retina/citologia , Células Ganglionares da Retina/citologia , Visão Ocular/fisiologia , Potenciais de Ação/fisiologia , Animais , Fluorescência , Camundongos , Camundongos Transgênicos , Microscopia Confocal , Modelos Biológicos , Estimulação Luminosa
10.
Proc Natl Acad Sci U S A ; 109(43): 17663-8, 2012 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-23045641

RESUMO

Single progenitors can give rise to any and all of the main retinal cell types: photoreceptors, interneurons (horizontal, bipolar, and amacrine cells), retinal ganglion cells (RGCs), and glia. Many of these types are divisible into multiple functionally, structurally, and molecularly distinct subtypes (e.g., ~25 for RGCs). It remains unknown when and how progenitors become committed to generate such subtypes. Here, we determine the origin of RGCs that respond selectively to vertical motion and express cadherin 6 (cdh6). Using Cre recombinase-based lineage tracing, we show that these RGCs arise from progenitors that themselves express cdh6. These progenitors are capable of generating all major retinal cell types, but the RGCs they generate are predominantly of the single direction-selective subtype. In contrast, cdh6-positive progenitors retain the ability to generate multiple subtypes of amacrine and bipolar cells. Our results demonstrate that type and subtype specification are regulated in different ways and suggest that multipotential but fate-restricted progenitors contribute to subtype specification in retina.


Assuntos
Células-Tronco Multipotentes/citologia , Células Ganglionares da Retina/citologia , Animais , Linhagem da Célula , Hibridização In Situ , Camundongos , Camundongos Endogâmicos C57BL
11.
Nature ; 452(7186): 478-82, 2008 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-18368118

RESUMO

The retina contains complex circuits of neurons that extract salient information from visual inputs. Signals from photoreceptors are processed by retinal interneurons, integrated by retinal ganglion cells (RGCs) and sent to the brain by RGC axons. Distinct types of RGC respond to different visual features, such as increases or decreases in light intensity (ON and OFF cells, respectively), colour or moving objects. Thus, RGCs comprise a set of parallel pathways from the eye to the brain. The identification of molecular markers for RGC subsets will facilitate attempts to correlate their structure with their function, assess their synaptic inputs and targets, and study their diversification. Here we show, by means of a transgenic marking method, that junctional adhesion molecule B (JAM-B) marks a previously unrecognized class of OFF RGCs in mice. These cells have asymmetric dendritic arbors aligned in a dorsal-to-ventral direction across the retina. Their receptive fields are also asymmetric and respond selectively to stimuli moving in a soma-to-dendrite direction; because the lens reverses the image of the world on the retina, these cells detect upward motion in the visual field. Thus, JAM-B identifies a unique population of RGCs in which structure corresponds remarkably to function.


Assuntos
Moléculas de Adesão Celular/metabolismo , Movimento (Física) , Retina/citologia , Células Ganglionares da Retina/citologia , Células Ganglionares da Retina/metabolismo , Animais , Biomarcadores/análise , Contagem de Células , Forma Celular , Dendritos/metabolismo , Imunoglobulinas , Camundongos , Modelos Neurológicos , Estimulação Luminosa , Retina/efeitos da radiação , Células Ganglionares da Retina/efeitos da radiação
12.
Trends Neurosci ; 47(4): 239-240, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38514350

RESUMO

A recent study by Cheung, Pauler, Koppensteiner et al. combining lineage tracing with single-cell RNA sequencing (scRNA-seq) has revealed unexpected features of the developing superior colliculus (SC). Extremely multipotent individual progenitors generate all types of SC neurons and glial cells that were found to localize in a non-predetermined pattern, demonstrating a remarkable degree of unpredictability in SC development.


Assuntos
Neurônios , Colículos Superiores , Humanos , Colículos Superiores/fisiologia , Neurônios/fisiologia , Neuroglia , Neurogênese
13.
Plants (Basel) ; 13(6)2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38592930

RESUMO

Gamma-ray irradiation is one of the most widely used mutagens worldwide. We previously conducted mutation breeding using gamma irradiation to develop new Citrus unshiu varieties. Among these mutants, Gwonje-early had an ovate shape, a protrusion of the upper part of the fruit, and a large fruit size compared with wild-type (WT) fruits. We investigated the external/internal morphological characteristics and fruit sugar/acid content of Gwonje-early. Additionally, we investigated genome-wide single-nucleotide polymorphisms (SNPs) and insertion/deletion (InDel) variants in Gwonje-early using whole-genome re-sequencing. Functional annotation by Gene Ontology analysis confirmed that InDels were more commonly annotated than SNPs. To identify specific molecular markers for Gwonje-early, allele-specific PCR was performed using homozygous SNPs detected via Gwonje-early genome re-sequencing. The GJ-SNP1 and GJ-SNP4 primer sets were effectively able to distinguish Gwonje-early from the WT and other commercial citrus varieties, demonstrating their use as specific molecular markers for Gwonje-early. These findings also have important implications in terms of intellectual property rights and the variety protection of Gwonje-early. Our results may provide insights into the understanding of morphological traits and the molecular breeding mechanisms of citrus species.

14.
Comput Biol Med ; 172: 108241, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38489987

RESUMO

Bolus segmentation is crucial for the automated detection of swallowing disorders in videofluoroscopic swallowing studies (VFSS). However, it is difficult for the model to accurately segment a bolus region in a VFSS image because VFSS images are translucent, have low contrast and unclear region boundaries, and lack color information. To overcome these challenges, we propose PECI-Net, a network architecture for VFSS image analysis that combines two novel techniques: the preprocessing ensemble network (PEN) and the cascaded inference network (CIN). PEN enhances the sharpness and contrast of the VFSS image by combining multiple preprocessing algorithms in a learnable way. CIN reduces ambiguity in bolus segmentation by using context from other regions through cascaded inference. Moreover, CIN prevents undesirable side effects from unreliably segmented regions by referring to the context in an asymmetric way. In experiments, PECI-Net exhibited higher performance than four recently developed baseline models, outperforming TernausNet, the best among the baseline models, by 4.54% and the widely used UNet by 10.83%. The results of the ablation studies confirm that CIN and PEN are effective in improving bolus segmentation performance.


Assuntos
Transtornos de Deglutição , Deglutição , Humanos , Fluoroscopia/métodos , Transtornos de Deglutição/diagnóstico por imagem , Algoritmos , Processamento de Imagem Assistida por Computador/métodos
15.
Plants (Basel) ; 12(19)2023 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-37836096

RESUMO

'Miyagawa-wase' mandarin (Citrus unshiu Marc. cv. Miyagawa-wase early) is one of the most widely cultivated citrus varieties on Jeju Island in Korea. Mutation breeding is a useful tool for the induction of genetic diversity for the rapid creation of new plant variants. We previously reported the use of gamma irradiation for the development of new citrus varieties. Here, we report a new mutant, Ara-unshiu, with a unique late fruit ripening phenotype. We investigated the fruit morphological characteristics including weight, vertical/transverse diameter, peel thickness, hardness, and color difference, as well as sugar and acid contents of the Ara-unshiu compared to wild-type controls. We then used whole genome re-sequencing and functional annotation by gene ontology to identify and characterize single nucleotide polymorphism (SNP) and insertion/deletion (InDel) variants in the Ara-unshiu, finding a greater abundance of annotated genes containing InDels compared to SNPs. Finally, we used allele-specific PCR to identify molecular markers among the homozygous SNPs detected from the Ara-unshiu genome sequencing. We report a primer set that effectively distinguishes the Ara-unshiu from the wild-type control and other citrus varieties. Our findings provide insights into the mechanisms controlling the timing of fruit ripening and tools for the molecular breeding of citrus varieties.

16.
Bioengineering (Basel) ; 10(11)2023 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-38002403

RESUMO

We propose a novel transfer learning framework for pathological image analysis, the Response-based Cross-task Knowledge Distillation (RCKD), which improves the performance of the model by pretraining it on a large unlabeled dataset guided by a high-performance teacher model. RCKD first pretrains a student model to predict the nuclei segmentation results of the teacher model for unlabeled pathological images, and then fine-tunes the pretrained model for the downstream tasks, such as organ cancer sub-type classification and cancer region segmentation, using relatively small target datasets. Unlike conventional knowledge distillation, RCKD does not require that the target tasks of the teacher and student models be the same. Moreover, unlike conventional transfer learning, RCKD can transfer knowledge between models with different architectures. In addition, we propose a lightweight architecture, the Convolutional neural network with Spatial Attention by Transformers (CSAT), for processing high-resolution pathological images with limited memory and computation. CSAT exhibited a top-1 accuracy of 78.6% on ImageNet with only 3M parameters and 1.08 G multiply-accumulate (MAC) operations. When pretrained by RCKD, CSAT exhibited average classification and segmentation accuracies of 94.2% and 0.673 mIoU on six pathological image datasets, which is 4% and 0.043 mIoU higher than EfficientNet-B0, and 7.4% and 0.006 mIoU higher than ConvNextV2-Atto pretrained on ImageNet, respectively.

17.
J Neurosci ; 31(21): 7753-62, 2011 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-21613488

RESUMO

The retina contains ganglion cells (RGCs) that respond selectively to objects moving in particular directions. Individual members of a group of ON-OFF direction-selective RGCs (ooDSGCs) detect stimuli moving in one of four directions: ventral, dorsal, nasal, or temporal. Despite this physiological diversity, little is known about subtype-specific differences in structure, molecular identity, and projections. To seek such differences, we characterized mouse transgenic lines that selectively mark ooDSGCs preferring ventral or nasal motion as well as a line that marks both ventral- and dorsal-preferring subsets. We then used the lines to identify cell surface molecules, including Cadherin 6, CollagenXXVα1, and Matrix metalloprotease 17, that are selectively expressed by distinct subsets of ooDSGCs. We also identify a neuropeptide, CART (cocaine- and amphetamine-regulated transcript), that distinguishes all ooDSGCs from other RGCs. Together, this panel of endogenous and transgenic markers distinguishes the four ooDSGC subsets. Patterns of molecular diversification occur before eye opening and are therefore experience independent. They may help to explain how the four subsets obtain distinct inputs. We also demonstrate differences among subsets in their dendritic patterns within the retina and their axonal projections to the brain. Differences in projections indicate that information about motion in different directions is sent to different destinations.


Assuntos
Percepção de Movimento/fisiologia , Estimulação Luminosa/métodos , Células Ganglionares da Retina/citologia , Células Ganglionares da Retina/metabolismo , Vias Visuais/citologia , Vias Visuais/metabolismo , Animais , Axônios/metabolismo , Axônios/ultraestrutura , Caderinas/biossíntese , Dendritos/metabolismo , Dendritos/ultraestrutura , Metaloproteinases da Matriz Associadas à Membrana/biossíntese , Camundongos , Camundongos Transgênicos , Retina/citologia , Retina/metabolismo
18.
Plants (Basel) ; 11(10)2022 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-35631762

RESUMO

Satsuma mandarin (Citrus unshiu Marc. cv. Miyagawa-wase) is the most widely cultivated citrus variety in Korea. Although most varieties are imported from Japan, efforts have focused on developing new domestic varieties. We produced mutants by irradiating C. unshiu Marc. cv. Miyagawa-wase scions with gamma rays and grafting them onto C. unshiu Marc. cv. Miyagawa-wase branches. We compared the characteristics of these mutants with Miyagawa-wase fruit as a control. A mutant line named Jedae-unshiu with a unique fruit shape was selected for investigation in detail. The phenotype of Jedae-unshiu fruit demonstrated vertical troughs on the flavedo, smooth albedo without rough protruding fibers, and good adhesion between peel and flesh. In addition, Jedae-unshiu had thicker peels and higher fruit hardness than the control. Higher levels of hesperetin and narirutin, representative flavonoids, accumulated in the peel and flesh of Jedae-unshiu than those of the control. Cellular-level microscopic observations of the mature fruit peels demonstrated epidermal cell disruption in the control but not in Jedae-unshiu. Our results suggest that Jedae-unshiu has high possibility for development as a good storage variety containing large amounts of flavonoids, in addition to potential for ornamental value due to the unique shape of the fruit.

19.
J Clin Med ; 11(11)2022 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-35683477

RESUMO

Self-expandable metallic stents (SEMSs) are typically inserted in patients with unresectable malignant biliary obstruction. However, SEMSs are susceptible to occlusion. To overcome this issue, we developed a large-bore, dumbbell-shaped, fully covered SEMS (FCSEMS-L) and compared its efficacy and safety with those of a conventional FCSEMS (FCSEMS-C) in patients with malignant biliary obstruction. METHODS: Patients with unresectable distal malignant biliary obstruction were retrospectively enrolled between January 2011 and February 2021. All patients underwent endoscopic insertion of FCSEMSs. Recurrent biliary obstruction (RBO), patient survival time, complications, and prognosis were analyzed. RESULTS: RBO occurred in 31 patients (35.6%) who received an FCSEMS-L, and in 34 (45.9%) who received an FCSEMS-C. Stent occlusion occurred in 19 patients (21.8%) who received an FCSEMS-L, and in 22 (29.7%) who received an FCSEMS-C. Stent migration occurred in 12 patients (13.8%) with an FCSEMS-L and 12 (16.2%) with an FCSEMS-C. The median time to RBO (TRBO) was 301 days with an FCSEMS-L and 203 days with an FCSEMS-C. The median survival time was 479 days with an FCSEMS-L and 523 days with an FCSEMS-C. The TRBO and patient survival time did not significantly differ between the two groups. CONCLUSIONS: There were no significant differences in efficacy and complication rates between the fully covered large bore SEMSs and conventional fully covered SEMSs.

20.
J Liver Cancer ; 22(1): 84-90, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37383537

RESUMO

There are various methods for treating advanced hepatocellular carcinoma with portal vein invasion, such as systemic chemotherapy, transarterial chemoembolization, transarterial radioembolization, and concurrent chemoradiotherapy. These methods have similar clinical efficacy but are designed with a palliative aim. Herein, we report a case that experienced complete remission through "associating liver partition and portal vein ligation for staged hepatectomy (ALPPS)" after concurrent chemoradiotherapy and hepatic artery infusion chemotherapy. In this patient, concurrent chemoradiotherapy and hepatic artery infusion chemotherapy induced substantial tumor shrinkage, and hypertrophy of the nontumor liver was sufficiently induced by portal vein ligation (stage 1 surgery) followed by curative resection (stage 2 surgery). Using this approach, long-term survival with no evidence of recurrence was achieved at 16 months. Therefore, the optimal use of ALPPS requires sufficient consideration in cases of significant hepatocellular carcinoma shrinkage for curative purposes.

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