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1.
Aging Cell ; : e14187, 2024 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-38716507

RESUMEN

Behavioral changes or neuropsychiatric symptoms (NPSs) are common features in dementia and are associated with accelerated cognitive impairment and earlier deaths. However, how NPSs are intertwined with cognitive decline remains elusive. In this study, we identify that the basolateral amygdala (BLA) is a key brain region that is associated with mood disorders and memory decline in the AD course. During the process from pre- to post-onset in AD, the dysfunction of parvalbumin (PV) interneurons and pyramidal neurons in the amygdala leads to hyperactivity of pyramidal neurons in the basal state and insensitivity to external stimuli. We further demonstrate that serotonin (5-HT) receptors in distinct neurons synergistically regulate the BLA microcircuit of AD rather than 5-HT levels, in which both restrained inhibitory inputs by excessive 5-HT1AR signaling in PV interneurons and depolarized pyramidal neurons via upregulated 5-HT2AR contribute to aberrant neuronal hyperactivity. Downregulation of these two 5-HT receptors simultaneously enables neurons to resist ß-amyloid peptides (Aß) neurotoxicity and ameliorates the mood and cognitive defects. Therefore, our study reveals a crucial role of 5-HT receptors for regulating neuronal homeostasis in AD pathogenesis, and this would provide early intervention and potential targets for AD cognitive decline.

2.
Med Phys ; 2024 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-38652084

RESUMEN

BACKGROUND: The application of deep learning methods in rapid bone scintigraphy is increasingly promising for minimizing the duration of SPECT examinations. Recent works showed several deep learning models based on simulated data for the synthesis of high-count bone scintigraphy images from low-count counterparts. Few studies have been conducted and validated on real clinical pairs due to the misalignment inherent in multiple scan procedures. PURPOSE: To generate high quality whole-body bone images from 2× and 3× fast scans using deep learning based enhancement method. MATERIALS AND METHODS: Seventy-six cases who underwent whole-body bone scans were enrolled in this prospective study. All patients went through a standard scan at a speed of 20 cm/min, which followed by fast scans consisting of 2× and 3× accelerations at speeds of 40 and 60 cm/min. A content-attention image restoration approach based on Residual-in-Residual Dense Block (RRDB) is introduced to effectively recover high-quality images from fast scans with fine-details and less noise. Our approach is robust with misalignment introduced from patient's metabolism, and shows valid count-level consistency. Learned Perceptual Image Patch Similarity (LPIPS) and Fréchet Inception Distance (FID) are employed in evaluating the similarity to the standard bone images. To further prove our method practical in clinical settings, image quality of the anonymous images was evaluated by two experienced nuclear physicians on a 5-point Likert scale (5 =  excellent) . RESULTS: The proposed method reaches the state-of-the-art performance on FID and LPIPS with 0.583 and 0.176 for 2× fast scans and 0.583 and 0.185 for 3× fast scans. Clinic evaluation further demonstrated the restored images had a significant improvement compared to fast scan in image quality, technetium 99m-methyl diphosphonate (Tc-99 m MDP) distribution, artifacts, and diagnostic confidence. CONCLUSIONS: Our method was validated for accelerating whole-body bone scans by introducing real clinical data. Confirmed by nuclear medicine physicians, the proposed method can effectively enhance image diagnostic value, demonstrating potential for efficient high-quality fast bone imaging in practical settings.

3.
Acta Crystallogr D Struct Biol ; 79(Pt 11): 1018-1025, 2023 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-37860963

RESUMEN

In recent years, the emergence of serial crystallography, initially pioneered at X-ray free-electron lasers (XFELs), has sparked a growing interest in collecting macromolecular crystallographic data at room temperature. Various fixed-target serial crystallography techniques have been developed, ranging from commercially available chips to in-house designs implemented at different synchrotron facilities. Nevertheless, there is currently no commercially available chip (known to the authors) specifically designed for the direct handling of oxygen-sensitive samples. This study presents a methodology employing silicon nitride chips arranged in a `sandwich' configuration, enabling reliable room-temperature data collection from oxygen-sensitive samples. The method involves the utilization of a custom-made 3D-printed assembling tool and a MX sample holder. To validate the effectiveness of the proposed method, deoxyhemoglobin and methemoglobin samples were investigated using the BioMAX X-ray macromolecular crystallography beamline, the Balder X-ray absorption spectroscopy beamline and UV-Vis absorption spectroscopy.


Asunto(s)
Oxígeno , Sincrotrones , Cristalografía , Anaerobiosis , Cristalografía por Rayos X , Sustancias Macromoleculares
4.
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi ; 39(10): 898-903, 2023 Oct.
Artículo en Chino | MEDLINE | ID: mdl-37882713

RESUMEN

Objective To investigate the fluorescence resonance energy transfer (FRET) effect between dylight (DL) and AuNP (AuNP), and to construct a new fluorescence immunoassay for insulin in combination with the immunocompetition method. Methods Insulin antigen (Ag) and insulin antibody (Ab) were conjugated with DL and AuNP respectively to form DL-Ag conjugate and AUNp-AB conjugate. A novel fluorescence immunoassay for insulin was developed on the basis of FRET effect and the immune competition response between them. Then the performance of the method was evaluated and its application in actual samples was explored. Results The fluorescence immunoassay showed high sensitivity (0.015 ng/mL), short measurement time (4 min) and good specificity. It was successfully used in the measurement of serum insulin, and the recovery was between 96.9% and 121.1%. Conclusion FRET effect between AuNP and DL can be applied to develop a fluorescence immunoassay for the measurement of serum insulin.


Asunto(s)
Transferencia Resonante de Energía de Fluorescencia , Insulina , Inmunoensayo
5.
IUCrJ ; 10(Pt 6): 729-737, 2023 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-37830774

RESUMEN

Serial and time-resolved macromolecular crystallography are on the rise. However, beam time at X-ray free-electron lasers is limited and most third-generation synchrotron-based macromolecular crystallography beamlines do not offer the necessary infrastructure yet. Here, a new setup is demonstrated, based on the JUNGFRAU detector and Jungfraujoch data-acquisition system, that enables collection of kilohertz serial crystallography data at fourth-generation synchrotrons. More importantly, it is shown that this setup is capable of collecting multiple-time-point time-resolved protein dynamics at kilohertz rates, allowing the probing of microsecond to second dynamics at synchrotrons in a fraction of the time needed previously. A high-quality complete X-ray dataset was obtained within 1 min from lysozyme microcrystals, and the dynamics of the light-driven sodium-pump membrane protein KR2 with a time resolution of 1 ms could be demonstrated. To make the setup more accessible for researchers, downstream data handling and analysis will be automated to allow on-the-fly spot finding and indexing, as well as data processing.

6.
J Synchrotron Radiat ; 30(Pt 5): 885-894, 2023 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-37526994

RESUMEN

In X-ray macromolecular crystallography (MX), single-wavelength anomalous dispersion (SAD) and multi-wavelength anomalous dispersion (MAD) techniques are commonly used for obtaining experimental phases. For an MX synchrotron beamline to support SAD and MAD techniques it is a prerequisite to have a reliable, fast and well automated energy scan routine. This work reports on a continuous energy scan procedure newly implemented at the BioMAX MX beamline at MAX IV Laboratory. The continuous energy scan is fully automated, capable of measuring accurate fluorescence counts over the absorption edge of interest while minimizing the sample exposure to X-rays, and is about a factor of five faster compared with a conventional step scan previously operational at BioMAX. The implementation of the continuous energy scan facilitates the prompt access to the anomalous scattering data, required for the SAD and MAD experiments.

7.
Artículo en Chino | MEDLINE | ID: mdl-37549952

RESUMEN

Myoepithelioma, also known as malignant myoepithelioma, is a rare malignant tumor originating from myoepithelial cell. This article reports a patient with a huge tumor in the neck and left elbow who underwent fine needle aspiration under local anesthesia. The pathological diagnosis was a myoepithelioma. Under general anesthesia, giant tumors in the lower neck, posterior cranial fossa, neck, and left elbow were removed, and postoperative pathology showed that they were all myoepithelial tumors. Immunohistochemistry showed AE1/AE3 (+), P63 (+), CK7 (+), CK5 (+), and CD138 (+). The clinical characteristics and diagnosis and treatment process of this case are reported and relevant literature is reviewed.


Asunto(s)
Carcinoma , Mioepitelioma , Humanos , Mioepitelioma/patología , Inmunohistoquímica , Células Epiteliales , Cuello/patología
9.
Phys Med Biol ; 68(13)2023 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-37307847

RESUMEN

Objectives. To evaluate the clinical performance of deep learning-enhanced ultrafast single photon emission computed tomography/computed tomography (SPECT/CT) bone scans in patients with suspected malignancy.Approach. In this prospective study, 102 patients with potential malignancy were enrolled and underwent a 20 min SPECT/CT and a 3 min SPECT scan. A deep learning model was applied to generate algorithm-enhanced images (3 min DL SPECT). The reference modality was the 20 min SPECT/CT scan. Two reviewers independently evaluated general image quality, Tc-99m MDP distribution, artifacts, and diagnostic confidence of 20 min SPECT/CT, 3 min SPECT/CT, and 3 min DL SPECT/CT images. The sensitivity, specificity, accuracy, and interobserver agreement were calculated. The lesion maximum standard uptake value (SUVmax) of the 3 min DL and 20 min SPECT/CT images was analyzed. The peak signal-to-noise ratio (PSNR) and structure similarity index measure (SSIM) were evaluated.Main results. The 3 min DL SPECT/CT images showed significantly superior general image quality, Tc-99m MDP distribution, artifacts, and diagnostic confidence than the 20 min SPECT/CT images (P< 0.0001). The diagnostic performance of the 20 min and 3 min DL SPECT/CT images was similar for reviewer 1 (pairedX2= 0.333,P= 0.564) and reviewer 2 (pairedX2= 0.05,P= 0.823). The diagnosis results for the 20 min (kappa = 0.822) and 3 min DL (kappa = 0.732) SPECT/CT images showed high interobserver agreement. The 3 min DL SPECT/CT images had significantly higher PSNR and SSIM than the 3 min SPECT/CT images (51.44 versus 38.44,P< 0.0001; 0.863 versus 0.752,P< 0.0001). The SUVmaxof the 3 min DL and 20 min SPECT/CT images showed a strong linear relationship (r= 0.991;P< 0.0001).Significance.Ultrafast SPECT/CT with a 1/7 acquisition time can be enhanced by a deep learning method to achieve comparable image quality and diagnostic value to those of standard acquisition.


Asunto(s)
Aprendizaje Profundo , Medronato de Tecnecio Tc 99m , Humanos , Estudios Prospectivos , Tomografía Computarizada por Tomografía Computarizada de Emisión de Fotón Único , Tomografía Computarizada de Emisión de Fotón Único/métodos
10.
Int J Clin Exp Pathol ; 16(3): 67-75, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37033394

RESUMEN

Salivary duct carcinoma (SDC) is a rare malignant tumor of the salivary gland and is most commonly found in the parotid gland, followed by the submandibular gland. Due to its rarity, there is no consensus on its treatment. Surgical resection is currently the only curative treatment. Considering its high degree of malignancy, extensive tumor resection and postoperative adjuvant radiotherapy are recommended. We report a rare case of SDC of the submandibular gland. A 62-year-old man presented to our hospital with complaints of swelling in the right submaxillary area for 4 months, rapidly growing, with pain for 10 days. After admission, fine needle aspiration (FNA) revealed right submandibular gland ductal carcinoma. Considering its aggressiveness, large size, and invasion of parapharyngeal and oral floor soft tissues, the patient received two cycles of neoadjuvant chemotherapy followed by extended surgical resection. Postoperatively, the patient received four cycles of concurrent chemoradiotherapy, followed by afatinib targeted therapy. No recurrence or metastasis was observed in a 45-month follow-up. Thus we present a comprehensive treatment for salivary duct carcinoma combining neoadjuvant chemotherapy with surgery, postoperative concurrent radiotherapy, and chemotherapy followed by afatinib targeted therapy.

11.
J Appl Crystallogr ; 56(Pt 2): 449-460, 2023 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-37032973

RESUMEN

Serial femtosecond crystallography was initially developed for room-temperature X-ray diffraction studies of macromolecules at X-ray free electron lasers. When combined with tools that initiate biological reactions within microcrystals, time-resolved serial crystallography allows the study of structural changes that occur during an enzyme catalytic reaction. Serial synchrotron X-ray crystallography (SSX), which extends serial crystallography methods to synchrotron radiation sources, is expanding the scientific community using serial diffraction methods. This report presents a simple flow cell that can be used to deliver microcrystals across an X-ray beam during SSX studies. This device consists of an X-ray transparent glass capillary mounted on a goniometer-compatible 3D-printed support and is connected to a syringe pump via light-weight tubing. This flow cell is easily mounted and aligned, and it is disposable so can be rapidly replaced when blocked. This system was demonstrated by collecting SSX data at MAX IV Laboratory from microcrystals of the integral membrane protein cytochrome c oxidase from Thermus thermophilus, from which an X-ray structure was determined to 2.12 Šresolution. This simple SSX platform may help to lower entry barriers for non-expert users of SSX.

12.
Artículo en Chino | MEDLINE | ID: mdl-36987964

RESUMEN

Neuroendocrine carcinoma(NEC) is a malignant tumor derived from neuroendocrine cells, with distinct clinical, morphological and immunohistochemical characteristics. Neuroendocrine carcinoma of the head and neck is very rare in clinic. Larynx is the most common affected site, and the root of the tongue is extremely rare. The clinical manifestations are mainly eating pain, cauliflower like mass in the mouth, and ulcerative lesions that have not healed for a long time. Maxillofacial MRI and contrastenhanced CT are the most commonly used examination tools for such diseases, which can detect the spaceoccupying lesions of tumors. Neuroendocrine granules found in the cytoplasm under pathological light microscope can be diagnosed as neuroendocrine carcinoma. However, for most cases, it is difficult to make a diagnosis only under light microscope, and it is often necessary to make a diagnosis by means of immunohistochemistry and other technical means. This paper reports a case of neuroendocrine carcinoma of the root of the tongue, introduces its characteristics, diagnosis and treatment, and reviews the relevant literature of this case.


Asunto(s)
Carcinoma Neuroendocrino , Laringe , Humanos , Carcinoma Neuroendocrino/patología , Lengua , Cuello/patología , Laringe/patología , Boca/patología
14.
Proc Natl Acad Sci U S A ; 120(9): e2219952120, 2023 02 28.
Artículo en Inglés | MEDLINE | ID: mdl-36802416

RESUMEN

Social behavior starts with dynamic approach prior to the final consummation. The flexible processes ensure mutual feedback across social brains to transmit signals. However, how the brain responds to the initial social stimuli precisely to elicit timed behaviors remains elusive. Here, by using real-time calcium recording, we identify the abnormalities of EphB2 mutant with autism-associated Q858X mutation in processing long-range approach and accurate activity of prefrontal cortex (dmPFC). The EphB2-dependent dmPFC activation precedes the behavioral onset and is actively associated with subsequent social action with the partner. Furthermore, we find that partner dmPFC activity is responsive coordinately to the approaching WT mouse rather than Q858X mutant mouse, and the social defects caused by the mutation are rescued by synchro-optogenetic activation in dmPFC of paired social partners. These results thus reveal that EphB2 sustains neuronal activation in the dmPFC that is essential for the proactive modulation of social approach to initial social interaction.


Asunto(s)
Corteza Prefrontal , Receptor EphB2 , Conducta Social , Animales , Ratones , Encéfalo , Neuronas/fisiología , Corteza Prefrontal/fisiología , Receptor EphB2/genética , Receptor EphB2/fisiología
15.
Transl Neurodegener ; 12(1): 1, 2023 01 09.
Artículo en Inglés | MEDLINE | ID: mdl-36624510

RESUMEN

BACKGROUND: Ribosomal protein S6 kinase 1 (S6K1) is a serine-threonine kinase that has two main isoforms: p70S6K (70-kDa isoform) and p85S6K (85-kDa isoform). p70S6K, with its upstream mammalian target of rapamycin (mTOR), has been shown to be involved in learning and memory and participate in the pathophysiology of Alzheimer's disease (AD). However, the function of p85S6K has long been neglected due to its high similarity to p70S6k. The role of p85S6K in learning and memory is still largely unknown. METHODS: We fractionated the postsynaptic densities to illustrate the differential distribution of p85S6K and p70S6K. Coimmunoprecipitation was performed to unveil interactions between p85S6K and the GluA1 subunit of AMPA receptor. The roles of p85S6K in synaptic targeting of GluA1 and learning and memory were evaluated by specific knockdown or overexpression of p85S6K followed by a broad range of methodologies including immunofluorescence, Western blot, in situ proximity ligation assay, morphological staining and behavioral examination. Further, the expression level of p85S6K was measured in brains from AD patients and AD model mice. RESULTS: p85S6K, but not p70S6K, was enriched in the postsynaptic densities. Moreover, knockdown of p85S6K resulted in defective spatial and recognition memory. In addition, p85S6K could interact with the GluA1 subunit of AMPA receptor through synapse-associated protein 97 and A-kinase anchoring protein 79/150. Mechanistic studies demonstrated that p85S6K could directly phosphorylate GluA1 at Ser845 and increase the amount of GluA1 in synapses, thus sustaining synaptic function and spine densities. Moreover, p85S6K was found to be specifically decreased in the synaptosomal compartment in the brains of AD patients and AD mice. Overexpression of p85S6K ameliorated the synaptic deficits and cognitive impairment in transgenic AD model mice. CONCLUSIONS: These results strongly imply a significant role for p85S6K in maintaining synaptic and cognitive function by interacting with GluA1. The findings provide an insight into the rational targeting of p85S6K as a therapeutic potential for AD.


Asunto(s)
Enfermedad de Alzheimer , Disfunción Cognitiva , Animales , Ratones , Enfermedad de Alzheimer/genética , Receptores AMPA , Disfunción Cognitiva/genética , Cognición , Ratones Transgénicos , Mamíferos
17.
Med Phys ; 50(6): 3612-3622, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36542389

RESUMEN

BACKGROUND: Ultra-high resolution computed tomography (UHRCT) has shown great potential for the detection of pulmonary diseases. However, UHRCT scanning generally induces increases in scanning time and radiation exposure. Super resolution is a gradually prosperous application in CT imaging despite higher radiation dose. Recent works have proved that the convolution neural network especially the generative adversarial network (GAN) based model could generate high-resolution CT using phantom images or simulated low resolution data without extra dose. Research that used clinical CT particularly lung images are rare due to the difficulty in collecting paired dataset. PURPOSE: To generate clinical UHRCT in lung from low resolution computed tomography (LRCT) using a GAN model. METHODS: 43 clinical scans with LRCT and UHRCT were collected in this study. Paired patches were selected using the structural similarity index measure (SSIM) and the peak signal-to-noise ratio (PSNR) threshold. A relativistic GAN with gradient guidance was trained to learn the mapping from LRCT to UHRCT. The performance of the proposed method was evaluated using PSNR and SSIM. A reader study with five-point Likert score (five for the worst and one for the best) is also applied to assess the proposed method in terms of general quality, diagnostic confidence, sharpness and denoise level. RESULTS: Experimental results show that our method got PSNR 32.60 ± 2.92 and SSIM 0.881 ± 0.057 on our clinical CT dataset, outperforming other state-of-the-art methods based on the simulated scenarios. Moreover, reader study shows that our method reached the good clinical performance in terms of general quality (1.14 ± 0.36), diagnostic confidence (1.36 ± 0.49), sharpness (1.07 ± 0.27) and high denoise level (1.29 ± 0.61) compared to other SR methods. CONCLUSION: This study demonstrated the feasibility of generating UHRCT images from LRCT without longer scanning time or increased radiation dose.


Asunto(s)
Procesamiento de Imagen Asistido por Computador , Tomografía Computarizada por Rayos X , Procesamiento de Imagen Asistido por Computador/métodos , Tomografía Computarizada por Rayos X/métodos , Redes Neurales de la Computación , Pulmón , Relación Señal-Ruido
18.
ACS Omega ; 7(45): 41013-41020, 2022 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-36406567

RESUMEN

Materials with a high specific surface area including a porous structure have been widely researched due to the applicability in the adsorption of various organic dyes. However, further application of porous materials is limited by the complicated and expensive preparation process. Herein, a Sn-Ni coating with a polyporous structure is successfully prepared via a simple and high-efficiency electrodeposition approach in deep eutectic solvents (DESs). The prepared Sn-Ni coating exhibits a uniform polyporous structure with a diameter of 15 µm. Furthermore, the coating shows excellent adsorption capacity in the removal of acid grain black organic dyestuff. With the rise of preparation temperature from 85 to 105 °C, the electrochemical active surface area and the ratio of nickel increase, which further enhance dye adsorption capacity.

19.
Nat Commun ; 13(1): 5540, 2022 09 21.
Artículo en Inglés | MEDLINE | ID: mdl-36130959

RESUMEN

Threat and extinction memories are crucial for organisms' survival in changing environments. These memories are believed to be encoded by separate ensembles of neurons in the brain, but their whereabouts remain elusive. Using an auditory fear-conditioning and extinction paradigm in male mice, here we discovered that two distinct projection neuron subpopulations in physical proximity within the insular cortex (IC), targeting the central amygdala (CeA) and nucleus accumbens (NAc), respectively, to encode fear and extinction memories. Reciprocal intracortical inhibition of these two IC subpopulations gates the emergence of either fear or extinction memory. Using rabies-virus-assisted tracing, we found IC-NAc projection neurons to be preferentially innervated by intercortical inputs from the orbitofrontal cortex (OFC), specifically enhancing extinction to override fear memory. These results demonstrate that IC serves as an operation node harboring distinct projection neurons that decipher fear or extinction memory under the top-down executive control from OFC.


Asunto(s)
Extinción Psicológica , Miedo , Animales , Extinción Psicológica/fisiología , Miedo/fisiología , Masculino , Ratones , Neuronas/fisiología , Núcleo Accumbens/fisiología , Corteza Prefrontal/fisiología
20.
Anal Biochem ; 658: 114899, 2022 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-36126761

RESUMEN

In this study, a homogeneous enzyme-free ratiometric (HOMO- EF-RA) immunoassay was developed for the sensitive detection of C-peptide. In the immunoassay, there have been a miscible detection system by mixing with the fluorescent quantum dots conjugated antigen (QD-Ag conjugates) and the dylight dye conjugated antibody (DL-Ab conjugates). When connecting between Ag-QD conjugate and Ab-DL conjugate by specific recognition, the system emitted fluorescence resonant energy transfer (FRET). The target C-peptide can inhibit the connection and FRET formation between QD-Ag conjugates and DL-Ab conjugates, thus changing the dual fluorescence. By measuring the ratio dual fluorescence changes of the system, the content of C-peptide was evaluated without any enzyme used and multiple incubation and washing steps. This immunoassay realized the highly sensitive (as low as 0.12 ng mL-1), selective and rapid (as less as 6 min) detection of C-peptide. Furthermore, the simple and convenient immunoassay was applied successfully to the determination of C-peptide in real serum samples.


Asunto(s)
Puntos Cuánticos , Péptido C , Puntos Cuánticos/química , Inmunoensayo , Espectrometría de Fluorescencia , Anticuerpos/química , Transferencia Resonante de Energía de Fluorescencia
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