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1.
BMC Infect Dis ; 24(1): 96, 2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38233756

RESUMO

BACKGROUND: Whether human T-lymphotropic virus type 1 (HTLV-1) carriers can develop sufficient humoral immunity after coronavirus disease 2019 (COVID-19) vaccination is unknown. METHODS: To investigate humoral immunity after COVID-19 vaccination in HTLV-1 carriers, a multicenter, prospective observational cohort study was conducted at five institutions in southwestern Japan, an endemic area for HTLV-1. HTLV-1 carriers and HTLV-1-negative controls were enrolled for this study from January to December 2022. During this period, the third dose of the COVID-19 vaccine was actively administered. HTLV-1 carriers were enrolled during outpatient visits, while HTLV-1-negative controls included health care workers and patients treated by participating institutions for diabetes, hypertension, or dyslipidemia. The main outcome was the effect of HTLV-1 infection on the plasma anti-COVID-19 spike IgG (IgG-S) titers after the third dose, assessed by multivariate linear regression with other clinical factors. RESULTS: We analyzed 181 cases (90 HTLV-1 carriers, 91 HTLV-1-negative controls) after receiving the third dose. HTLV-1 carriers were older (median age 67.0 vs. 45.0 years, p < 0.001) and more frequently had diabetes, hypertension, or dyslipidemia than did HTLV-1-negative controls (60.0% vs. 27.5%, p < 0.001). After the third dose, the IgG-S titers decreased over time in both carriers and controls. Multivariate linear regression in the entire cohort showed that time since the third dose, age, and HTLV-1 infection negatively influenced IgG-S titers. After adjusting for confounders such as age, or presence of diabetes, hypertension, or dyslipidemia between carriers and controls using the overlap weighting propensity score method, and performing weighted regression analysis in the entire cohort, both time since the third dose and HTLV-1 infection negatively influenced IgG-S titers. CONCLUSIONS: The humoral immunity after the third vaccination dose is impaired in HTLV-1 carriers; thus, customized vaccination schedules may be necessary for them.


Assuntos
COVID-19 , Diabetes Mellitus , Dislipidemias , Infecções por HTLV-I , Vírus Linfotrópico T Tipo 1 Humano , Hipertensão , Humanos , Idoso , COVID-19/prevenção & controle , Vacinas contra COVID-19 , Imunidade Humoral , Estudos Prospectivos , Vacinação , Imunoglobulina G , Anticorpos Antivirais
2.
J Neurosci ; 42(45): 8460-8467, 2022 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-36351832

RESUMO

Dendrites receive the vast majority of a single neuron's inputs, and coordinate the transformation of these signals into neuronal output. Ex vivo and theoretical evidence has shown that dendrites possess powerful processing capabilities, yet little is known about how these mechanisms are engaged in the intact brain or how they influence circuit dynamics. New experimental and computational technologies have led to a surge in interest to unravel and harness their computational potential. This review highlights recent and emerging work that combines established and cutting-edge technologies to identify the role of dendrites in brain function. We discuss active dendritic mediation of sensory perception and learning in neocortical and hippocampal pyramidal neurons. Complementing these physiological findings, we present theoretical work that provides new insights into the underlying computations of single neurons and networks by using biologically plausible implementations of dendritic processes. Finally, we present a novel brain-computer interface task, which assays somatodendritic coupling to study the mechanisms of biological credit assignment. Together, these findings present exciting progress in understanding how dendrites are critical for in vivo learning and behavior, and highlight how subcellular processes can contribute to our understanding of both biological and artificial neural computation.


Assuntos
Dendritos , Células Piramidais , Dendritos/fisiologia , Células Piramidais/fisiologia , Neurônios/fisiologia , Hipocampo , Aprendizagem , Modelos Neurológicos , Potenciais de Ação/fisiologia
3.
BMC Endocr Disord ; 23(1): 276, 2023 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-38110958

RESUMO

BACKGROUND: Primary adrenal leiomyosarcoma is a rare and aggressive mesenchymal tumor derived from the smooth muscle wall of a central adrenal vein or its tributaries; therefore, tumors tend to invade the inferior vena cava and cause thrombosis. The great majority of tumors grow rapidly, which makes the disease difficult to diagnose in its early clinical stages and needs differentiation from adrenocortical carcinomas for the selection of chemotherapy including mitotane which causes adrenal insufficiency. CASE PRESENTATION: We presented two patients with adrenal leiomyosarcoma who were referred to our hospital with abdominal pain and harboring large adrenal tumors and inferior vena cava thrombosis. The endocrine findings, including serum catecholamine levels, were unremarkable. These two patients were considered clinically inoperable, and CT-guided core needle biopsy was performed to obtain the definitive histopathological diagnosis and determine the modes of therapy. The masses were subsequently diagnosed as primary adrenal leiomyosarcoma based on the histological features and positive immunoreactivity for SMA (smooth muscle actin), desmin, and vimentin. CONCLUSIONS: Adrenal leiomyosarcoma derived from the smooth muscle wall of a central adrenal vein or its tributaries is rare but should be considered a differential diagnosis in the case of nonfunctioning adrenal tumors extending directly to the inferior vena cava. CT-guided biopsy is considered useful for histopathological diagnosis and clinical management of patients with inoperable advanced adrenal tumors without any hormone excess.


Assuntos
Neoplasias do Córtex Suprarrenal , Neoplasias das Glândulas Suprarrenais , Leiomiossarcoma , Trombose , Humanos , Leiomiossarcoma/diagnóstico , Leiomiossarcoma/patologia , Trombose/diagnóstico , Neoplasias das Glândulas Suprarrenais/diagnóstico por imagem , Diagnóstico Diferencial , Neoplasias do Córtex Suprarrenal/diagnóstico
4.
J Phys Ther Sci ; 35(3): 257-264, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36866018

RESUMO

[Purpose] This study aimed to compare the predictive accuracy of walking ability at discharge among subacute stroke inpatients at 6 months post-discharge in terms of community ambulation level and establish optimal cut-off values. [Participants and Methods] This prospective observational study included 78 patients who completed follow-up assessments. Patients were classified into three groups based on the Modified Functional Walking Category (household/most limited community walkers, least limited community walkers, and unlimited community walkers) obtained by telephone survey at 6 months post-discharge. Predictive accuracy and cut-off values for discriminating among groups were calculated from 6-minute walking distance and comfortable walking speed measured at the time of discharge using receiver operating characteristic curves. [Results] Between household/most limited and least limited community walkers, 6-minute walking distance and comfortable walking speed offered similar predictive accuracy (area under the curve, 0.6-0.7), with cut-off values of 195 m and 0.56 m/s, respectively. Between least limited and unlimited community walkers, the areas under the curve were 0.896 for 6-minute walking distance and 0.844 for comfortable walking speed, with cut-off values of 299 m and 0.94 m/s, respectively. [Conclusion] Walking endurance and walking speed among inpatients with subacute stroke provided superior predictive accuracy for unlimited community walkers at 6 months post-discharge.

5.
J Xray Sci Technol ; 30(4): 777-788, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35527620

RESUMO

BACKGROUND: Head computed tomography (CT) is a commonly used imaging modality in radiology facilities. Since multiplanar reconstruction (MPR) processing can produce different results depending on the medical staff in charge, there is a possibility that the antemortem and postmortem images of the same person could be assessed and identified differently. OBJECTIVE: To propose and test a new automatic MPR method in order to address and overcome this limitation. METHODS: Head CT images of 108 cases are used. We employ the standardized transformation of statistical parametric mapping 8. The affine transformation parameters are obtained by standardizing the captured CT images. Automatic MPR processing is performed by using this parameter. The sphenoidal sinus of the orbitomeatal cross section of the automatic MPR processing of this study and the conventional manual MPR processing are cropped with a matrix size of 128×128, and the value of zero mean normalized correlation coefficient is calculated. RESULTS: The computed zero mean normalized cross-correlation coefficient (Rzncc) of≥0.9, 0.8≤Rzncc < 0.9 and 0.7≤Rzncc < 0.8 are achieved in 105 cases (97.2%), 2 cases (1.9%), and 1 case (0.9%), respectively. The average Rzncc was 0.96±0.03. CONCLUSION: Using the proposed new method in this study, MPR processing with guaranteed accuracy is efficiently achieved.


Assuntos
Processamento de Imagem Assistida por Computador , Tomografia Computadorizada por Raios X , Humanos , Neuroimagem
6.
J Org Chem ; 86(8): 5973-5982, 2021 04 16.
Artigo em Inglês | MEDLINE | ID: mdl-33829786

RESUMO

Boronic acid-catalyzed regioselective Koenigs-Knorr-type glycosylation is presented. The reaction of an unprotected or partially protected glycosyl acceptor with a glycosyl halide donor in the presence of silver oxide and a low catalytic amount of imidazole-containing boronic acid was found to proceed smoothly, which enables construction of a 1,2-trans glycosidic linkage with high regioselectivities. This is the first example of the use of a boronic acid catalyst to initiate regioselective glycosylation via the activation of cis-vicinal diols in glycosyl acceptors.


Assuntos
Ácidos Borônicos , Glicosídeos , Catálise , Glicosilação
7.
Cancer Sci ; 111(7): 2385-2399, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32385953

RESUMO

The tumor microenvironment (TME) consists of various components including cancer cells, tumor vessels, cancer-associated fibroblasts (CAFs), and inflammatory cells. These components interact with each other via various cytokines, which often induce tumor progression. Thus, a greater understanding of TME networks is crucial for the development of novel cancer therapies. Many cancer types express high levels of TGF-ß, which induces endothelial-to-mesenchymal transition (EndMT), leading to formation of CAFs. Although we previously reported that CAFs derived from EndMT promoted tumor formation, the molecular mechanisms underlying these interactions remain to be elucidated. Furthermore, tumor-infiltrating inflammatory cells secrete various cytokines, including TNF-α. However, the role of TNF-α in TGF-ß-induced EndMT has not been fully elucidated. Therefore, this study examined the effect of TNF-α on TGF-ß-induced EndMT in human endothelial cells (ECs). Various types of human ECs underwent EndMT in response to TGF-ß and TNF-α, which was accompanied by increased and decreased expression of mesenchymal cell and EC markers, respectively. In addition, treatment of ECs with TGF-ß and TNF-α exhibited sustained activation of Smad2/3 signals, which was presumably induced by elevated expression of TGF-ß type I receptor, TGF-ß2, activin A, and integrin αv, suggesting that TNF-α enhanced TGF-ß-induced EndMT by augmenting TGF-ß family signals. Furthermore, oral squamous cell carcinoma-derived cells underwent epithelial-to-mesenchymal transition (EMT) in response to humoral factors produced by TGF-ß and TNF-α-cultured ECs. This EndMT-driven EMT was blocked by inhibiting the action of TGF-ßs. Collectively, our findings suggest that TNF-α enhances TGF-ß-dependent EndMT, which contributes to tumor progression.


Assuntos
Transição Epitelial-Mesenquimal , Transdução de Sinais , Fator de Crescimento Transformador beta/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Biomarcadores , Fibroblastos Associados a Câncer/metabolismo , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patologia , Linhagem Celular , Células Cultivadas , Células Endoteliais/metabolismo , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Humanos , Mediadores da Inflamação/metabolismo , Neoplasias Bucais/tratamento farmacológico , Neoplasias Bucais/genética , Neoplasias Bucais/metabolismo , Neoplasias Bucais/patologia , NF-kappa B/metabolismo , Receptor do Fator de Crescimento Transformador beta Tipo I , Transdução de Sinais/efeitos dos fármacos , Proteína Smad2/metabolismo , Proteína Smad3/metabolismo , Fator de Crescimento Transformador beta/farmacologia , Microambiente Tumoral/genética , Fator de Necrose Tumoral alfa/farmacologia
8.
Shinrigaku Kenkyu ; 87(6): 579-89, 2017 Feb.
Artigo em Japonês | MEDLINE | ID: mdl-29630293

RESUMO

This study focuses on two questionnaire surveys that were conducted about the adoption of the Private Finance Initiative (PFI prison) method in Japan as a new correctional system. For study 1, a Web questionnaire was administered to residents of within a 30 km zone of Tokyo as well as those in Yamaguchi Prefecture to determine familiarity and resistance to the PFI prison systems. For study 2, a questionnaire survey was administered to residents of a neighborhood near a PFI prison in Mine city. The results showed that the attitudes toward the PFI prison were more positive in this area. Furthermore, contact with the correctional systems promoted residents' acceptance of prisoners and former prisoners. Finally, we discuss social and institutional support and contact with social systems to promote social inclusion.


Assuntos
Adaptação Psicológica , Prisioneiros/psicologia , Comportamento Social , Adulto , Idoso , Atitude , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prisões , Adulto Jovem
9.
Bioorg Med Chem Lett ; 25(3): 639-41, 2015 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-25529741

RESUMO

Incubation of bacteriopheophytin (BPhe) a, which was a demetalated pigment of bacteriochlorophyll a in photosynthetic bacteria, in CH2Cl2 in the presence of TiO2 particles with bubbling O2 in the dark produced a pigment absorbing 814nm. Detailed characterization of the novel pigment isolated from the CH2Cl2 suspension revealed that bacteriopurpurin-18 phytyl ester possessing an anhydride-type six-membered exocyclic E-ring was majorly formed by the treatment with TiO2 particles under oxygenic conditions. Oxidation of the bacteriochlorin ring in BPhe a, namely formations of derivatives of 3-acetyl pheophytin a and 3-acetyl protopheophytin a, can barely be detected through the conversion processes.


Assuntos
Oxigênio/química , Feofitinas/química , Porfirinas/química , Titânio/química , Catálise , Ésteres , Cloreto de Metileno/química , Oxirredução , Porfirinas/síntese química , Espectroscopia de Infravermelho com Transformada de Fourier
10.
Cereb Cortex ; 23(2): 293-304, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22314044

RESUMO

Cortical synaptic strengths vary substantially from synapse to synapse and exhibit a skewed distribution with a small fraction of synapses generating extremely large depolarizations. Using multiple whole-cell recordings from rat hippocampal CA3 pyramidal cells, we found that the amplitude of unitary excitatory postsynaptic conductances approximates a lognormal distribution and that in the presence of synaptic background noise, the strongest fraction of synapses could trigger action potentials in postsynaptic neurons even with single presynaptic action potentials, a phenomenon termed interpyramid spike transmission (IpST). The IpST probability reached 80%, depending on the network state. To examine how IpST impacts network dynamics, we simulated a recurrent neural network embedded with a few potent synapses. This network, unlike many classical neural networks, exhibited distinctive behaviors resembling cortical network activity in vivo. These behaviors included the following: 1) infrequent ongoing activity, 2) firing rates of individual neurons approximating a lognormal distribution, 3) asynchronous spikes among neurons, 4) net balance between excitation and inhibition, 5) network activity patterns that was robust against external perturbation, 6) responsiveness even to a single spike of a single excitatory neuron, and 7) precise firing sequences. Thus, IpST captures a surprising number of recent experimental findings in vivo. We propose that an unequally biased distribution with a few select strong synapses helps stabilize sparse neuronal activity, thereby reducing the total spiking cost, enhancing the circuit responsiveness, and ensuring reliable information transfer.


Assuntos
Potenciais de Ação/fisiologia , Região CA3 Hipocampal/fisiologia , Rede Nervosa/fisiologia , Transmissão Sináptica/fisiologia , Animais , Potenciais Pós-Sinápticos Excitadores/fisiologia , Feminino , Masculino , Técnicas de Patch-Clamp , Ratos , Ratos Wistar
11.
Chem Commun (Camb) ; 60(4): 448-451, 2024 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-38088060

RESUMO

A boronic acid-catalyzed peptide bond formation from α-amino acid methyl esters is described. The catalysis showed high chemoselectivity for ß-hydroxy-α-amino esters, affording the peptides in high to excellent yields with high functional group tolerance. This hydroxy-directed peptide bond formation could be applicable to oligopeptide syntheses. This is the first successful example of organoboron-catalyzed peptide bond formation from α-amino acid-derived inert esters.

12.
J Neurochem ; 126(3): 360-71, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23678982

RESUMO

Muscarinic acetylcholine receptors (mAChRs) are well known to transmit extracellular cholinergic signals into the cytoplasm from their position on the cell surface. However, we show here that M1-mAChRs are also highly expressed on intracellular membranes in neurons of the telencephalon and activate signaling cascades distinct from those of cell surface receptors, contributing uniquely to synaptic plasticity. Radioligand-binding experiments with cell-permeable and -impermeable ligands and immunohistochemical observations revealed intracellular and surface distributions of M1-mAChRs in the hippocampus and cortex of rats, mice, and humans, in contrast to the selective occurrence on the cell surface in other tissues. All intracellular muscarinic-binding sites were abolished in M1-mAChR-gene-knockout mice. Activation of cell surface M1-mAChRs in rat hippocampal neurons evoked phosphatidylinositol hydrolysis and network oscillations at theta rhythm, and transiently enhanced long-term potentiation. On the other hand, activation of intracellular M1-mAChRs phosphorylated extracellular-regulated kinase 1/2 and gradually enhanced long-term potentiation. Our data thus demonstrate that M1-mAChRs function at both surface and intracellular sites in telencephalon neurons including the hippocampus, suggesting a new mode of cholinergic transmission in the central nervous system.


Assuntos
Hipocampo/metabolismo , Plasticidade Neuronal/fisiologia , Receptor Muscarínico M1/metabolismo , Idoso , Idoso de 80 Anos ou mais , Animais , Western Blotting , Membrana Celular/química , Membrana Celular/metabolismo , Citoplasma/química , Citoplasma/metabolismo , Feminino , Humanos , Imuno-Histoquímica , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Pessoa de Meia-Idade , Neurônios/metabolismo , Técnicas de Patch-Clamp , Ratos , Ratos Wistar , Sinapses/metabolismo , Transmissão Sináptica/fisiologia
13.
Bioorg Med Chem Lett ; 23(3): 886-92, 2013 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-23273411

RESUMO

We synthesized various C8-naphthylethynylated 2'-deoxyadenosine derivatives and investigated their photophysical properties. Among them, cyano- and N,N-dimethylamino-substituted 8-naphthylethynylated 2'-deoxyadenosine derivatives ((cn)A and (dn)A) showed strong fluorescence with high quantum yields and a remarkable solvatofuorochromicity. In particular, fluorescence of N,N-dimethylamino-substituted (2,6dn)A was not quenched by neighboring guanines (Gs) when incorporated in DNA duplexes, in contrast to (cn)A. We developed a new fluorescent probe containing (2,6dn)A that can be used for the detection of target DNA via a bulge formation regardless of the neighboring sequences.


Assuntos
DNA/análise , Desoxiadenosinas/química , Corantes Fluorescentes/química , Naftalenos/química , DNA/química , Corantes Fluorescentes/síntese química , Limite de Detecção , Estrutura Molecular
15.
Proc Natl Acad Sci U S A ; 107(22): 10244-9, 2010 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-20479225

RESUMO

Spike synchronization underlies information processing and storage in the brain. But how can neurons synchronize in a noisy network? By exploiting a high-speed (500-2,000 fps) multineuron imaging technique and a large-scale synapse mapping method, we directly compared spontaneous activity patterns and anatomical connectivity in hippocampal CA3 networks ex vivo. As compared to unconnected pairs, synaptically coupled neurons shared more common presynaptic neurons, received more correlated excitatory synaptic inputs, and emitted synchronized spikes with approximately 10(7) times higher probability. Importantly, common presynaptic parents per se synchronized more than unshared upstream neurons. Consistent with this, dynamic-clamp stimulation revealed that common inputs alone could not account for the realistic degree of synchronization unless presynaptic spikes synchronized among common parents. On a macroscopic scale, network activity was coordinated by a power-law scaling of synchronization, which engaged varying sets of densely interwired (thus highly synchronized) neuron groups. Thus, locally coherent activity converges on specific cell assemblies, thereby yielding complex ensemble dynamics. These segmentally synchronized pulse packets may serve as information modules that flow in associatively parallel network channels.


Assuntos
Rede Nervosa/fisiologia , Potenciais de Ação , Animais , Mapeamento Encefálico/métodos , Região CA1 Hipocampal/citologia , Região CA1 Hipocampal/fisiologia , Região CA3 Hipocampal/citologia , Região CA3 Hipocampal/fisiologia , Sinalização do Cálcio , Fenômenos Eletrofisiológicos , Potenciais Pós-Sinápticos Excitadores , Técnicas In Vitro , Potenciais Pós-Sinápticos Inibidores , Modelos Neurológicos , Rede Nervosa/citologia , Neurônios/fisiologia , Técnicas de Patch-Clamp , Ratos , Ratos Wistar
16.
Jpn J Radiol ; 41(5): 561-568, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36538162

RESUMO

PURPOSE: The liver is the largest organ in the abdomen and is often irradiated in radiotherapy for non-hepatic malignancies. As most of the studies on changes in liver volume are on hepatocellular carcinoma based on liver dysfunction, there are few studies on healthy liver. In this study, we investigated the relationship between absorbed dose and changes in liver volume after chemoradiotherapy for esophageal cancer in patients without apparent pre-treatment liver dysfunction. MATERIALS AND METHODS: Liver volume was compared between pre-treatment, acute (< 4 months) and late post-treatment (≥ 4 and < 13 months) phases in 12 patients using abdominal plain CT images. Volume changes were evaluated separately for the right and left lobes. We investigated the relationship between the volume change and VxGy (percentage of volume received x Gy or more dose). In addition, volume change for each absorbed dose was investigated using deformable image registration. RESULTS: The volume of the left lobe showed a significant decrease between pre-treatment and acute post-treatment phases (p < 0.001), while the volume of right lobe and between acute and late post-treatment phase of left lobe did not. The mean value of the volume reduction rate of the left lobe was 51.1% and equivalent to the mean value of V30Gy. As a result of the volume change for each absorbed dose, the volume reduction rate increased as the absorbed dose increased, and a significant volume loss was observed at doses above 11 Gy. CONCLUSION: Volume of the liver significantly decreased only in the acute phase after chemoradiotherapy for esophageal cancer. The tolerable dose for a healthy liver is generally considered to be 30 Gy, but attention should be paid to lower doses to avoid radiation-induced liver injury.


Assuntos
Carcinoma Hepatocelular , Neoplasias Esofágicas , Neoplasias Hepáticas , Lesões por Radiação , Humanos , Dosagem Radioterapêutica , Carcinoma Hepatocelular/terapia , Carcinoma Hepatocelular/radioterapia , Neoplasias Esofágicas/diagnóstico por imagem , Neoplasias Esofágicas/terapia , Quimiorradioterapia/efeitos adversos , Neoplasias Hepáticas/terapia , Neoplasias Hepáticas/radioterapia , Abdome
17.
Trends Neurosci ; 46(11): 895-897, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37690954

RESUMO

The anterior lateral motor area (ALM) is crucial in preparing and executing voluntary movements through its diverse neuronal subpopulations that target different subcortical areas. A recent study by Xu et al. utilized an elaborate viral tracing strategy in mice to provide comprehensive whole-brain maps of monosynaptic inputs to the major descending pathways of ALM.


Assuntos
Encéfalo , Neurônios , Camundongos , Animais , Neurônios/fisiologia , Movimento
18.
Chem Commun (Camb) ; 59(48): 7391-7394, 2023 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-37232102

RESUMO

Although aqueous ammonia is an inexpensive and readily available safe source of ammonia, there have been no successful studies on direct catalytic dehydrative amidations of carboxylic acids with aqueous ammonia. In this study, we report a catalytic methodology for the synthesis of primary amides through diboronic acid anhydride (DBAA)-catalyzed dehydrative condensation of carboxylic acids with aqueous ammonia as the amine substrate.

19.
Diagnostics (Basel) ; 13(13)2023 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-37443680

RESUMO

In a few cases, postmortem computed tomography angiography (PMCTA) is effective in postmortem detection of cortical artery rupture causing subdural hematoma (SDH), which is difficult to detect at autopsy. Here, we explore the usefulness and limitations of PMCTA in detecting the sites of cortical arterial rupture for SDH. In 6 of 10 cases, extravascular leakage of contrast material at nine different places enabled PMCTA to identify cortical arterial rupture. PMCTA did not induce destructive arterial artifacts, which often occur during autopsy. We found that, although not in all cases, PMCTA could show the site of cortical arterial rupture causing subdural hematoma in some cases. This technique is beneficial for cases of SDH autopsy, as it can be performed nondestructively and before destructive artifacts from the autopsy occur.

20.
J Neurosci ; 31(37): 13168-79, 2011 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-21917800

RESUMO

Neural circuitry is a self-organizing arithmetic device that converts input to output and thereby remodels its computational algorithm to produce more desired output; however, experimental evidence regarding the mechanism by which information is modified and stored while propagating across polysynaptic networks is sparse. We used functional multineuron calcium imaging to monitor the spike outputs from thousands of CA1 neurons in response to the stimulation of two independent sites of the dentate gyrus in rat hippocampal networks ex vivo. Only pyramidal cells were analyzed based on post hoc immunostaining. Some CA1 pyramidal cells were observed to fire action potentials only when both sites were simultaneously stimulated (AND-like neurons), whereas other neurons fired in response to either site of stimulation but not to concurrent stimulation (XOR-like neurons). Both types of neurons were interlaced in the same network and altered their logical operation depending on the timing of paired stimulation. Repetitive paired stimulation for brief periods induced a persistent reorganization of AND and XOR operators, suggesting a flexibility in parallel distributed processing. We simulated these network functions in silico and found that synaptic modification of the CA3 recurrent excitation is pivotal to the shaping of logic plasticity. This work provides new insights into how microscopic synaptic properties are associated with the mesoscopic dynamics of complex microcircuits.


Assuntos
Região CA1 Hipocampal/fisiologia , Região CA3 Hipocampal/fisiologia , Giro Denteado/fisiologia , Vias Neurais/fisiologia , Células Piramidais/fisiologia , Transmissão Sináptica/fisiologia , Potenciais de Ação/fisiologia , Animais , Contagem de Células , Estimulação Elétrica/métodos , Feminino , Técnicas In Vitro , Masculino , Modelos Neurológicos , Ratos , Ratos Wistar
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