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1.
Mol Cell ; 81(22): 4722-4735.e5, 2021 11 18.
Artículo en Inglés | MEDLINE | ID: mdl-34626566

RESUMEN

Rapid protein degradation enables cells to quickly modulate protein abundance. Dysregulation of short-lived proteins plays essential roles in disease pathogenesis. A focused map of short-lived proteins remains understudied. Cycloheximide, a translational inhibitor, is widely used in targeted studies to measure degradation kinetics for short-lived proteins. Here, we combined cycloheximide chase assays with advanced quantitative proteomics to map short-lived proteins under translational inhibition in four human cell lines. Among 11,747 quantified proteins, we identified 1,017 short-lived proteins (half-lives ≤ 8 h). These short-lived proteins are less abundant, evolutionarily younger, and less thermally stable than other proteins. We quantified 103 proteins with different stabilities among cell lines. We showed that U2OS and HCT116 cells express truncated forms of ATRX and GMDS, respectively, which have lower stability than their full-length counterparts. This study provides a large-scale resource of human short-lived proteins under translational arrest, leading to untapped avenues of protein regulation for therapeutic interventions.


Asunto(s)
Proteínas/química , Proteoma , Proteómica/métodos , Alanina/análogos & derivados , Alanina/química , Línea Celular , Línea Celular Tumoral , Cicloheximida/química , Cicloheximida/farmacología , Fucosa/química , Geminina/química , Células HCT116 , Células HEK293 , Humanos , Péptidos/química , Análisis de Componente Principal , Biosíntesis de Proteínas , Proteínas/efectos de los fármacos , Control de Calidad , ARN Interferente Pequeño/metabolismo , Telómero/química
2.
Proc Natl Acad Sci U S A ; 121(12): e2317218121, 2024 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-38483997

RESUMEN

Across the animal kingdom, visual predation relies on motion-sensing neurons in the superior colliculus (SC) and its orthologs. These neurons exhibit complex stimulus preferences, including direction selectivity, which is thought to be critical for tracking the unpredictable escape routes of prey. The source of direction selectivity in the SC is contested, and its contributions to predation have not been tested experimentally. Here, we use type-specific cell removal to show that narrow-field (NF) neurons in the mouse SC guide predation. In vivo recordings demonstrate that direction-selective responses of NF cells are independent of recently reported stimulus-edge effects. Monosynaptic retrograde tracing reveals that NF cells receive synaptic input from direction-selective ganglion cells. When we eliminate direction selectivity in the retina of adult mice, direction-selective responses in the SC, including in NF cells, are lost. However, eliminating retinal direction selectivity does not affect the hunting success or strategies of mice, even when direction selectivity is removed after mice have learned to hunt, and despite abolishing the gaze-stabilizing optokinetic reflex. Thus, our results identify the retinal source of direction selectivity in the SC. They show that NF cells in the SC guide predation, an essential spatial orienting task, independent of their direction selectivity, revealing behavioral multiplexing of complex neural feature preferences and highlighting the importance of feature-selective manipulations for neuroethology.


Asunto(s)
Neuronas , Conducta Predatoria , Ratones , Animales , Neuronas/fisiología , Colículos Superiores/fisiología , Retina , Vías Visuales/fisiología
3.
Proc Natl Acad Sci U S A ; 121(6): e2311733121, 2024 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-38285951

RESUMEN

In contrast to prevalent strategies which make use of ß-sheet mimetics to block Aß fibrillar growth, in this study, we designed a series of sulfonyl-γ-AApeptide helices that targeted the crucial α-helix domain of Aß13-26 and stabilized Aß conformation to avoid forming the neurotoxic Aß oligomeric ß-sheets. Biophysical assays such as amyloid kinetics and TEM demonstrated that the Aß oligomerization and fibrillation could be greatly prevented and even reversed in the presence of sulfonyl-γ-AApeptides in a sequence-specific and dose-dependent manner. The studies based on circular dichroism, Two-dimensional nuclear magnetic resonance spectroscopy (2D-NMR) spectra unambiguously suggested that the sulfonyl-γ-AApeptide Ab-6 could bind to the central region of Aß42 and induce α-helix conformation in Aß. Additionally, Electrospray ionisation-ion mobility spectrometry-mass spectrometry (ESI-IMS-MS) was employed to rule out a colloidal mechanism of inhibitor and clearly supported the capability of Ab-6 for inhibiting the formation of Aß aggregated forms. Furthermore, Ab-6 could rescue neuroblastoma cells by eradicating Aß-mediated cytotoxicity even in the presence of pre-formed Aß aggregates. The confocal microscopy demonstrated that Ab-6 could still specifically bind Aß42 and colocalize into mitochondria in the cellular environment, suggesting the rescue of cell viability might be due to the protection of mitochondrial function otherwise impaired by Aß42 aggregation. Taken together, our studies indicated that sulfonyl-γ-AApeptides as helical peptidomimetics could direct Aß into the off-pathway helical secondary structure, thereby preventing the formation of Aß oligomerization, fibrillation and rescuing Aß induced cell cytotoxicity.


Asunto(s)
Amidas , Péptidos beta-Amiloides , Amiloide , Amiloide/química , Conformación Proteica en Hélice alfa , Conformación Molecular , Péptidos beta-Amiloides/metabolismo , Fragmentos de Péptidos/metabolismo
4.
FASEB J ; 38(2): e23409, 2024 01 31.
Artículo en Inglés | MEDLINE | ID: mdl-38193628

RESUMEN

Diabetic kidney disease (DKD) is one of the severe complications of diabetes mellitus, yet there is no effective treatment. Exploring the development of DKD is essential to treatment. Podocyte injury and inflammation are closely related to the development of DKD. However, the mechanism of podocyte injury and progression in DKD remains largely unclear. Here, we observed that FTO expression was significantly upregulated in high glucose-induced podocytes and that overexpression of FTO promoted podocyte injury and inflammation. By performing RNA-seq and MeRIP-seq with control podocytes and high glucose-induced podocytes with or without FTO knockdown, we revealed that serum amyloid A2 (SAA2) is a target of FTO-mediated m6A modification. Knockdown of FTO markedly increased SAA2 mRNA m6A modification and decreased SAA2 mRNA expression. Mechanistically, we demonstrated that SAA2 might participate in podocyte injury and inflammation through activation of the NF-κB signaling pathway. Furthermore, by generating podocyte-specific adeno-associated virus 9 (AAV9) to knockdown SAA2 in mice, we discovered that the depletion of SAA2 significantly restored podocyte injury and inflammation. Together, our results suggested that upregulation of SAA2 promoted podocyte injury through m6A-dependent regulation, thus suggesting that SAA2 may be a therapeutic target for diabetic kidney disease.


Asunto(s)
Dioxigenasa FTO Dependiente de Alfa-Cetoglutarato , Nefropatías Diabéticas , Podocitos , Proteína Amiloide A Sérica , Animales , Ratones , Dioxigenasa FTO Dependiente de Alfa-Cetoglutarato/genética , Nefropatías Diabéticas/genética , Glucosa , Inflamación/genética , FN-kappa B , ARN Mensajero/genética , Transducción de Señal , Proteína Amiloide A Sérica/genética
5.
Drug Resist Updat ; 73: 101038, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38181587

RESUMEN

AIMS: Although cefiderocol (FDC) is not prescribed in China, FDC-resistant pandrug-resistant hypervirulent Klebsiella pneumoniae (PDR-hvKp) is emerging. In this study, we performed FDC susceptibility testing of clinical Kp isolates to explore the prevalence of FDC-resistant isolates and the mechanism of FDC-resistance. METHODS: We retrospectively selected 151 carbapenem-resistant Kp isolates to assess FDC susceptibility. Seven isolates harboring blaSHV-12 from two patients were enrolled for whole-genome sequencing. The antimicrobial resistance, virulence, blaSHV-12 expression, and fitness costs in different media were examined. The amplification of blaSHV-12 was further investigated by qPCR and long-read sequencing. RESULTS: The 151 isolates showed a low MIC50/MIC90 (1/4 mg/L) of FDC. The seven isolates were ST11 PDR-hvKp, and two represented FDC-resistance (MIC=32 mg/L). The IncR/IncFII plasmids of two FDC-resistant isolates harbored 6 and 15 copies of blaSHV-12, whereas four FDC-susceptible isolates carried one copy and one harbored three copies. These blaSHV-12 genes concatenated together and were located within the same 7.3 kb fragment flanked by IS26, which contributed to the increased expression and FDC resistance without fitness costs. The amplification of blaSHV-12 and FDC resistance could be induced by FDC in vitro and reversed during continuous passage. CONCLUSIONS: The amplification of blaSHV-12 and the consequent dynamic within-host heteroresistance are important concerns for the rational application of antibiotics. Long-read sequencing might be a superior way to detect resistance gene amplification rapidly and accurately.


Asunto(s)
Infecciones por Klebsiella , Klebsiella pneumoniae , Humanos , Klebsiella pneumoniae/genética , Cefiderocol , Estudios Retrospectivos , Infecciones por Klebsiella/tratamiento farmacológico , Infecciones por Klebsiella/epidemiología , Pruebas de Sensibilidad Microbiana , Antibacterianos/farmacología , Antibacterianos/uso terapéutico
6.
BMC Microbiol ; 24(1): 56, 2024 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-38347440

RESUMEN

BACKGROUND: The occurrence of multidrug-resistant and hypervirulent Klebsiella pneumoniae (MDR-hvKp) worldwide poses a great challenge for public health. Few studies have focused on ST218 MDR-hvKp. METHODS: Retrospective genomic surveillance was conducted at the Peking University Third Hospital from 2017 and clinical information was obtained. To understand genomic and microbiological characteristics, antimicrobial susceptibility testing, plasmid conjugation and stability, biofilm formation, serum killing, growth curves and whole-genome sequencing were performed. We also assessed the clinical and microbiological characteristics of ST218 compared with ST23. RESULTS: A total of eleven ST218 Kp isolates were included. The most common infection type was lower respiratory tract infection (72.7%, 8/11) in our hospital, whereas ST23 hvKp (72.7%, 8/11) was closely associated with bloodstream infection. Notably, nosocomial infections caused by ST218 (54.5%, 6/11) was slightly higher than ST23 (36.4%, 4/11). All of the ST218 and ST23 strains presented with the virulence genes combination of iucA + iroB + peg344 + rmpA + rmpA2. Interestingly, the virulence score of ST218 was lower than ST23, whereas one ST218 strain (pPEKP3107) exhibited resistance to carbapenems, cephalosporins, ß-lactamase/inhibitors and quinolones and harbored an ~ 59-kb IncN type MDR plasmid carrying resistance genes including blaNDM-1, dfrA14 and qnrS1. Importantly, blaNDM-1 and qnrS1 were flanked with IS26 located within the plasmid that could successfully transfer into E. coli J53. Additionally, PEKP2044 harbored an ~ 41-kb resistance plasmid located within tetA indicating resistance to doxycycline. CONCLUSION: The emergence of blaNDM-1 revealed that there is great potential for ST218 Kp to become a high-risk clone for MDR-hvKp, indicating the urgent need for enhanced genomic surveillance.


Asunto(s)
Infecciones por Klebsiella , Klebsiella pneumoniae , Humanos , beta-Lactamasas/genética , Estudios Retrospectivos , Escherichia coli , Resistencia a Múltiples Medicamentos , Infecciones por Klebsiella/microbiología , Antibacterianos/farmacología , Antibacterianos/uso terapéutico
7.
Opt Lett ; 49(20): 5897-5900, 2024 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-39404566

RESUMEN

To build a galvanometer-driven dual-camera sensing system, it is important to accurately correlate the wide-view image coordinates with the pan-tilt mirror angles for adjusting the incident light path of the zoom-in camera. Existing optical modeling methods assume sufficient target distance and simplify dual-camera optical centers as coincident. However, this simplification is not valid in many practical cases and might cause severe system malfunctions, such as complete loss tracking of important targets. To address this problem, we propose a novel approach, to the best of our knowledge, to facilitate high-precision optical modeling and calibration of galvanometer-driven dual-camera systems. The proposed method takes into consideration the dual-camera optical center misalignment issue and builds a model for accurate estimation and rectification of target localization errors under various optical configurations. Qualitative and quantitative experimental results demonstrate the superiority of our method, improving the performance of galvanometer-driven dual-camera systems for high-precision optical sensing applications.

8.
Opt Lett ; 49(20): 5707-5710, 2024 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-39404518

RESUMEN

Liquid crystal (LC) distributed feedback (DFB) lasers hold significant potential for integrated photonics applications. However, limitations in wavelength spacing for wavelength switching, device size, and compatibility with other technologies have impeded advancements of the LC DFB laser in integration and responsiveness. Herein, we propose a thin-film multi-wavelength DFB laser array utilizing high-resolution patterned programmable nematic LC polymers, enabling rapid switching with high-resolution wavelength spacing between wavelength division multiplexing channels while maintaining a stable single longitudinal mode (SLM) for each laser. The underlying physical mechanism involves modulating the effective refractive index of the DFB laser by varying the LC molecules' orientation angles between adjacent regions of the LC grating to achieve wavelength modulation. Additionally, a specialized LC waveguide design connects the DFB lasers, facilitating wavelength modulation as well as straight-line and bending propagation of the laser. Furthermore, the laser array demonstrates a relatively low energy threshold, facilitating its applications in high-integration scenarios.

9.
Chemistry ; : e202402302, 2024 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-39327935

RESUMEN

Antibiotic resistance has been threatening public health for a long period, while the COVID pandemic aggravated the scenario. To combat antibiotic resistance strains, host defense peptides (HDPs) mimicking molecules have attracted considerable attention. Herein, we reported a series of polycarbonates bearing cationic lysine amino acid residues that could mimic the mechanism of action of HDPs and possess broad-spectrum antimicrobial activity. Moreover, those polymers had negligible toxicity toward red blood cells and mammalian cells. The membrane-disruption mechanism endows the lysine-containing polycarbonates with low possibility of resistance development and the fast killing kinetics, making them promising candidates for antimicrobial development.

10.
BMC Public Health ; 24(1): 807, 2024 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-38486191

RESUMEN

BACKGROUND: The objective of this study was to detect the urinary levels of chlorpyrifos, paraquat, and cyproconazole in residents living in Fuyang City and to analyze the correlation between these urinary pesticides levels and the severity of fatty liver disease (FLD). METHODS: All participants' fat fraction (FF) values were recorded by MRI (Magnetic resonance imaging). First-morning urine samples were collected from 53 participants from Fuyang Peoples'Hospital. The levels of three urinary pesticides were measured using ß-glucuronidase hydrolysis followed by a. The results were analyzed by using Pearson correlation analysis and binary logistic regression analysis to reveal the correlation between three urinary pesticides and the severity of fatty liver. RESULTS: 53 individuals were divided into 3 groups based on the results from MRI, with 20 cases in the normal control group, 16 cases in the mild fatty liver group, and 17 cases in the moderate and severe fatty liver group. Urinary chlorpyrifos level was increased along with the increase of the severity of fatty liver. Urinary paraquat level was significantly higher both in the low-grade fatty liver group and moderate & serve grade fatty liver group compared with the control group. No significant differences in urinary cyproconazole levels were observed among the three groups. Furthermore, urinary chlorpyrifos and paraquat levels were positively correlated with FF value. And chlorpyrifos was the risk factor that may be involved in the development of FLD and Receiver Operating Characteristic curve (ROC curve) analysis showed that chlorpyrifos and paraquat may serve as potential predictors of FLD. CONCLUSION: The present findings indicate urinary chlorpyrifos and paraquat were positively correlated with the severity of fatty liver. Moreover, urinary chlorpyrifos and paraquat have the potential to be considered as the predictors for development of FLD. Thus, this study may provide a new perspective from the environmental factors for the diagnosis, prevention, and treatment of FLD.


Asunto(s)
Cloropirifos , Enfermedad del Hígado Graso no Alcohólico , Plaguicidas , Triazoles , Humanos , Cloropirifos/orina , Paraquat , Imagen por Resonancia Magnética
11.
Drug Resist Updat ; 68: 100957, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36990047

RESUMEN

Resistance to epidermal growth factor receptor (EGFR) inhibitors, from the first-generation erlotinib to the third generation osimertinib, is a clinical challenge in the treatment of patients with EGFR-mutant lung adenocarcinoma. Our previous work found that a novel allosteric inhibitor of phosphoglycerate mutase 1 (PGAM1), HKB99, restrains erlotinib resistance in lung adenocarcinoma cells. However, the role of HKB99 in osimertinib resistance and its underlying molecular mechanism remains to be elucidated. Herein, we found that IL-6/JAK2/STAT3 signaling pathway is aberrantly activated in both erlotinib and osimertinib resistant cells. Importantly, HKB99 significantly blocks the interaction of PGAM1 with JAK2 and STAT3 via the allosteric sites of PGAM1, which leads to inactivation of JAK2/STAT3 and thereby disrupts IL-6/JAK2/STAT3 signaling pathway. Consequently, HKB99 remarkably restores EGFR inhibitor sensitivity and exerts synergistic tumoricidal effect. Additionally, HKB99 alone or in combination with osimertinib down-regulated the level of p-STAT3 in xenograft tumor models. Collectively, this study identifies PGAM1 as a key regulator in IL-6/JAK2/STAT3 axis in the development of resistance to EGFR inhibitors, which could serve as a therapeutic target in lung adenocarcinoma with acquired resistance to EGFR inhibitors.


Asunto(s)
Adenocarcinoma del Pulmón , Neoplasias Pulmonares , Humanos , Clorhidrato de Erlotinib/farmacología , Clorhidrato de Erlotinib/uso terapéutico , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/genética , Interleucina-6/genética , Interleucina-6/farmacología , Interleucina-6/uso terapéutico , Fosfoglicerato Mutasa/metabolismo , Fosfoglicerato Mutasa/farmacología , Resistencia a Antineoplásicos , Adenocarcinoma del Pulmón/tratamiento farmacológico , Adenocarcinoma del Pulmón/genética , Adenocarcinoma del Pulmón/patología , Receptores ErbB , Transducción de Señal , Inhibidores de Proteínas Quinasas/farmacología , Inhibidores de Proteínas Quinasas/uso terapéutico , Mutación , Línea Celular Tumoral , Janus Quinasa 2/genética , Janus Quinasa 2/metabolismo , Janus Quinasa 2/farmacología
12.
Ecotoxicol Environ Saf ; 281: 116563, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38878560

RESUMEN

Evodiamine (EVO), the main active alkaloid in Evodia rutaecarpa, was shown to exert various pharmacological activities, especially anti-tumor. Currently, it is considered a potential anti-cancer drug due to its excellent anti-tumor activity, which unfortunately has adverse reactions, such as the risk of liver and kidney injury, when Evodia rutaecarpa containing EVO is used clinically. In the present study, we aim to clarify the potential toxic target organs and toxicity mechanism of EVO, an active monomer in Evodia rutaecarpa, and to develop mitigation strategies for its toxicity mechanism. Transcriptome analysis and related experiments showed that the PI3K/Akt pathway induced by calcium overload was an important step in EVO-induced apoptosis of renal cells. Specifically, intracellular calcium ions were increased, and mitochondrial calcium ions were decreased. In addition, EVO-induced calcium overload was associated with TRPV1 receptor activation. In vivo TRPV1 antagonist and calcium chelator effects were observed to significantly reduce body weight loss and renal damage in mice due to EVO toxicity. The potential nephrotoxicity of EVO was further confirmed by an in vivo test. In conclusion, TRPV1-mediated calcium overload-induced apoptosis is one of the mechanisms contributing to the nephrotoxicity of EVO due to its toxicity, whereas maintaining body calcium homeostasis is an effective measure to reduce toxicity. These studies suggest that the clinical use of EVO-containing herbal medicines should pay due attention to the changes in renal function of patients as well as the off-target effects of the drugs.


Asunto(s)
Apoptosis , Calcio , Evodia , Homeostasis , Riñón , Quinazolinas , Quinazolinas/toxicidad , Quinazolinas/farmacología , Animales , Homeostasis/efectos de los fármacos , Calcio/metabolismo , Ratones , Apoptosis/efectos de los fármacos , Riñón/efectos de los fármacos , Riñón/patología , Evodia/química , Masculino , Canales Catiónicos TRPV/metabolismo , Quelantes del Calcio/farmacología
13.
Ren Fail ; 46(1): 2326186, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38466161

RESUMEN

BACKGROUND: Immune checkpoint inhibitor-associated acute kidney injury (ICI-AKI) is the most common renal complication and has attracted increasing amounts of attention. However, studies on this topic in Chinese cancer patients are very limited. Therefore, we conducted a retrospective study on the incidence, risk factors, clinical features and renal recovery of ICI-AKI in all patients with malignancies treated with ICIs in Shandong Provincial Hospital Affiliated to Shandong First Medical University. METHODS: In this single-center retrospective cohort study, the data of 904 patients who received immune checkpoint inhibitors (ICIs) treatment were retrospectively analyzed. Multivariable logistic regression was used to identify the predictors of ICI-AKI. RESULTS: A total of 46 of 904 patients receiving ICIs developed ICI-AKI, and the incidence of ICI-AKI was 5.1%. Patients developed ICI-AKI at a median of 9 weeks (IQR 3-23) after ICIs initiation. A lower baseline estimated glomerular filtration rate (eGFR) and use of antibiotics were associated with a higher risk of ICI-AKI. Renal recovery occurred in 17 patients (46%) at a median of 4 weeks (IQR 2-8) after ICI-AKI, including 16 (43%) with complete recovery and 1 (3%) with partial recovery. Of the 14 rechallenged patients, only one developed recurrent ICI-AKI. CONCLUSIONS: Patients with ICI-AKI were more likely to have impaired renal function at baseline and after treatment with antibiotics. Approximately half of the patients achieved renal recovery.


Asunto(s)
Lesión Renal Aguda , Inhibidores de Puntos de Control Inmunológico , Humanos , Estudios Retrospectivos , Inhibidores de Puntos de Control Inmunológico/efectos adversos , Lesión Renal Aguda/inducido químicamente , Lesión Renal Aguda/epidemiología , Riñón , Antibacterianos
14.
J Neurosci ; 42(13): 2678-2689, 2022 03 30.
Artículo en Inglés | MEDLINE | ID: mdl-35169021

RESUMEN

Dendrite and axon arbor sizes are critical to neuronal function and vary widely between different neuron types. The relative dendrite and axon sizes of synaptic partners control signal convergence and divergence in neural circuits. The developmental mechanisms that determine cell-type-specific dendrite and axon size and match synaptic partners' arbor territories remain obscure. Here, we discover that retinal horizontal cells express the leucine-rich repeat domain cell adhesion molecule AMIGO1. Horizontal cells provide pathway-specific feedback to photoreceptors-horizontal cell axons to rods and horizontal cell dendrites to cones. AMIGO1 selectively expands the size of horizontal cell axons. When Amigo1 is deleted in all or individual horizontal cells of either sex, their axon arbors shrink. By contrast, horizontal cell dendrites and synapse formation of horizontal cell axons and dendrites are unaffected by AMIGO1 removal. The dendrites of rod bipolar cells, which do not express AMIGO1, shrink in parallel with horizontal cell axons in Amigo1 knockout (Amigo1 KO) mice. This territory matching maintains the function of the rod bipolar pathway, preserving bipolar cell responses and retinal output signals in Amigo1 KO mice. We previously identified AMIGO2 as a scaling factor that constrains retinal neurite arbors. Our current results identify AMIGO1 as a scaling factor that expands retinal neurite arbors and reveal territory matching as a novel homeostatic mechanism. Territory matching interacts with other homeostatic mechanisms to stabilize the development of the rod bipolar pathway, which mediates vision near the threshold.SIGNIFICANCE STATEMENT Neurons send and receive signals through branched axonal and dendritic arbors. The size of these arbors is critical to the function of a neuron. Axons and dendrites grow during development and are stable at maturity. The mechanisms that determine axon and dendrite size are not well understood. Here, we identify a cell surface protein, AMIGO1, that selectively promotes axon growth of horizontal cells, a retinal interneuron. Removal of AMIGO1 reduces the size of horizontal cell axons without affecting the size of their dendrites or the ability of both arbors to form connections. The changes in horizontal cell axons are matched by changes in synaptic partner dendrites to stabilize retinal function. This identifies territory matching as a novel homeostatic plasticity mechanism.


Asunto(s)
Dendritas , Retina , Animales , Axones/fisiología , Dendritas/fisiología , Ratones , Células Bipolares de la Retina/fisiología , Células Fotorreceptoras Retinianas Conos/fisiología
15.
Neurobiol Dis ; 182: 106138, 2023 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-37105261

RESUMEN

Frontotemporal dementia (FTD) is an early onset dementia characterized by neuropathology and behavioural changes. A common genetic cause of FTD is haploinsufficiency of the gene progranulin (GRN). Mouse models of progranulin deficiency have provided insight into progranulin neurobiology, but the description of phenotypes with preclinical relevance has been limited in the currently available heterozygous progranulin-null mice. The identification of robust and reproducible FTD-associated behavioural, neuropathological, and biochemical phenotypes in progranulin deficient mice is a critical step in the preclinical development of therapies for FTD. In this work, we report the generation of a novel, 'humanized' mouse model of progranulin deficiency that expresses a single, targeted copy of human GRN in the absence of mouse progranulin. We also report the in-depth, longitudinal characterization of humanized progranulin-deficient mice and heterozygous progranulin-null mice over 18 months. Our analysis yielded several novel progranulin-dependent physiological and behavioural phenotypes, including increased marble burying, open field hyperactivity, and thalamic microgliosis in both models. RNAseq analysis of cortical tissue revealed an overlapping profile of transcriptomic dysfunction. Further transcriptomic analysis offers new insights into progranulin neurobiology. In sum, we have identified several consistent phenotypes in two independent mouse models of progranulin deficiency that are expected to be useful endpoints in the development of therapies for progranulin-deficient FTD. Furthermore, the presence of the human progranulin gene in the humanized progranulin-deficient mice will expedite the development of clinically translatable gene therapy strategies.


Asunto(s)
Demencia Frontotemporal , Enfermedad de Pick , Ratones , Humanos , Animales , Progranulinas/genética , Demencia Frontotemporal/patología , Transcriptoma , Ratones Noqueados , Mutación
16.
Br J Cancer ; 128(2): 168-176, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36396817

RESUMEN

BACKGROUND: The association between the use of angiotensin-converting enzyme inhibitors (ACEIs) and lung cancer risk remains controversial. This study evaluated the association between the use of ACEIs and lung cancer risk. METHODS: Records from five databases were searched from inception to 26 January 2022. Clinical studies involving persons aged ≥18 years with at least one year of follow-up and reporting adverse events, including lung cancer, were recorded with separate outcome reports supplied for the ACEIs and control groups. Data were extracted independently by three authors and pooled using a random-effects model. The primary outcome was lung cancer development. Odds ratios (ORs) with 95% confidence intervals (CIs) and lung cancer-related morbidity were calculated. RESULTS: Of 2400 records screened, 13,061,226 patients were included from seven cohort studies and four case-control studies. Pooled results showed that ACEIs use was linked to increased lung cancer risk (OR 1.19, 95% CI 1.05-1.36; P = 0.008), with high heterogeneity (I2 = 98%). CONCLUSIONS: ACEI usage is a greater risk factor for lung carcinogenesis than angiotensin receptor blocker use, especially in Asian patients. Further randomised controlled trials are needed to confirm the causal association between the use of ACEIs and lung cancer risk.


Asunto(s)
Inhibidores de la Enzima Convertidora de Angiotensina , Neoplasias Pulmonares , Humanos , Adolescente , Adulto , Inhibidores de la Enzima Convertidora de Angiotensina/efectos adversos , Antagonistas de Receptores de Angiotensina , Factores de Riesgo , Neoplasias Pulmonares/epidemiología , Estudios de Casos y Controles
17.
Pharmacol Res ; 197: 106955, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37820855

RESUMEN

Pancreatic ductal adenocarcinoma (PDAC) is one of the most aggressive and lethal malignancies lacking effective therapies. KRAS mutations that occur in over 90% of PDAC are major oncogenic drivers of PDAC. The MAPK signaling pathway plays a central role in KRAS-driven oncogenic signaling. However, pharmacological inhibitors of the MAPK pathway are poorly responded in KRAS-mutant PDAC, raising a compelling need to understand the mechanism behind and to seek new therapeutic solutions. Herein, we perform a screen utilizing a library composed of 800 naturally-derived bioactive compounds to identify natural products that are able to sensitize KRAS-mutant PDAC cells to the MAPK inhibition. We discover that tetrandrine, a natural bisbenzylisoquinoline alkaloid, shows a synergistic effect with MAPK inhibitors in PDAC cells and xenograft models. Mechanistically, pharmacological inhibition of the MAPK pathway exhibits a double-edged impact on the TRAIL-death receptor axis, transcriptionally upregulating TRAIL yet downregulating its agonistic receptors DR4 and DR5, which may explain the limited therapeutic outcomes of MAPK inhibitors in KRAS-mutant PDAC. Of great interest, tetrandrine stabilizes DR4/DR5 protein via impairing ubiquitination-mediated protein degradation, thereby allowing a synergy with MAPK inhibition in inducing apoptosis in KRAS-mutant PDAC. Our findings identify a new combinatorial approach for treating KRAS-mutant PDAC and highlight the role of TRAIL-DR4/DR5 axis in dictating the therapeutic outcome in KRAS-mutant PDAC.


Asunto(s)
Bencilisoquinolinas , Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Humanos , Proteínas Proto-Oncogénicas p21(ras)/genética , Neoplasias Pancreáticas/tratamiento farmacológico , Neoplasias Pancreáticas/genética , Carcinoma Ductal Pancreático/tratamiento farmacológico , Carcinoma Ductal Pancreático/genética , Bencilisoquinolinas/farmacología , Bencilisoquinolinas/uso terapéutico , Inhibidores de Proteínas Quinasas/farmacología , Inhibidores de Proteínas Quinasas/uso terapéutico , Receptores de Muerte Celular , Neoplasias Pancreáticas
18.
Malar J ; 22(1): 21, 2023 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-36658578

RESUMEN

BACKGROUND: Mass screening and treatment (MSAT) for malaria elimination lacks an ideal diagnostic tool to allow sensitive and affordable test of the target population in the field. This study evaluated whether Capture and Ligation Probe-PCR (CLIP-PCR) could be used in a field MSAT in Laiza City, Myanmar. METHODS: On day 0, two dried blood spots were collected from each participant. On day 1, all samples were screened for Plasmodium in a 20 m2 laboratory with workbench, a biosafety cabinet, a refrigerator, a benchtop shaking incubator and a qPCR machine, by four technicians using CLIP-PCR with sample pooling, at a health clinic of the Chinese bordering town of Nabang. On day 2, all positives were followed up and treated. RESULTS: Of 15,038 persons (65% of the total population) screened, 204 (1.36%) were CLIP-PCR positives. Among them, 188, 14, and 2 were infected with Plasmodium vivax, Plasmodium falciparum, and P. vivax/P. falciparum mix, respectively. The testing capacity was 538 persons/day, with a cost of US$0.92 /person. The proportion of submicroscopic infection was 64.7%. All positive individuals received treatment within 72 h after blood collection. CONCLUSION: Using CLIP-PCR in MSAT in low transmission settings can support the malaria elimination efforts in the China-Myanmar border region.


Asunto(s)
Malaria Falciparum , Malaria Vivax , Malaria , Humanos , Mianmar , Malaria/diagnóstico , Malaria/prevención & control , Plasmodium falciparum/genética , Plasmodium vivax/genética , Reacción en Cadena de la Polimerasa/métodos , China/epidemiología , Malaria Vivax/diagnóstico , Malaria Vivax/prevención & control , Malaria Vivax/epidemiología , Malaria Falciparum/epidemiología
19.
Ann Clin Microbiol Antimicrob ; 22(1): 11, 2023 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-36788555

RESUMEN

BACKGROUND: Klebsiella Pneumoniae (Kp) sequence type (ST) 147 has emerged globally and spread rapidly, particularly the extensively drug resistant (XDR) isolates. However, the infections caused by this subtype is rare reported in China for now. The clinical, microbiological and genomic characteristics are unclear. METHODS: A systemic retrospective study was conducted in a Chinese tertiary hospital. Clinical information of the infection cases was collected, and whole-genome sequencing and phenotypic experiments were performed on the ST147 isolates. The resistance and virulence genes were identified, and the plasmids harboring these genes were further studied. RESULTS: Six ST147 isolates from six patients among 720 available clincial Kp isolates were detected. Notably, two isolates, PEKP4035 and PEKP4265, represented both XDR and hypervirulence by acquiring blaOXA-48, blaCTX-M-15 and key virulence genes, iucA + rmpA2, representing no fitness cost and resulting fatal infection. Four of the six ST147 isolates presented with more nucleotide differences, whereas the PEKP4035 and PEKP4265 both isolated from the intensive care unit possessed 20 single nucleotide polymorphisms among one year, indicating the prolonged survive and transmission. Interestingly, the two isolates harbored the same fused plasmid composed of sul2 and iucA + rmpA2, which might be generated by recombination of a plasmid like KpvST101_OXA-48 with the pLVPK plasmid via IS26. Besides, two ~ 70 kb plasmids conferring multiple-drug resistance were also identified among the two isolates, which presented resistance genes including blaOXA-48, blaCTX-M-16, strA and strB. Interestingly, we reported that blaCTX-M-15, a common resistance gene within ST147, has successfully transferred into the chromosome by ISEcp1. CONCLUSIONS: XDR hypervirulent ST147 Kp is emerging, suggesting enhanced surveillance is essential.


Asunto(s)
Infecciones por Klebsiella , Klebsiella pneumoniae , Humanos , Klebsiella pneumoniae/genética , Klebsiella/genética , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Estudios Retrospectivos , Infecciones por Klebsiella/microbiología , Plásmidos/genética , beta-Lactamasas/genética
20.
Anesth Analg ; 137(4): 859-869, 2023 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-37010960

RESUMEN

BACKGROUND: We aimed to determine the preventive and therapeutic efficacy of modified manual chest compression (MMCC), a novel noninvasive and device-independent method, in reducing oxygen desaturation events in patients undergoing upper gastrointestinal endoscopy under deep sedation. METHODS: A total of 584 outpatients who underwent deep sedation during upper gastrointestinal endoscopy were enrolled. In the preventive cohort, 440 patients were randomized to the MMCC group (patients received MMCC when their eyelash reflex disappeared, M1 group) or control group (C1 group). In the therapeutic cohort, 144 patients with oxygen desaturation of a Sp o2 < 95% were randomized to MMCC group (patients who subsequently received MMCC, M2 group) or the conventional treatment group (C2 group). The primary outcomes were the incidence of desaturation episodes with an Sp o2 < 95% for the preventive cohort and the time spent below 95% Sp o2 for the therapeutic cohort. Secondary outcomes included the incidence of gastroscopy withdrawal and diaphragmatic pause. RESULTS: In the preventive cohort, MMCC reduced the incidence of desaturation episodes <95% (14.4% vs 26.1%; RR, 0.549; 95% confidence interval [CI], 0.37-0.815; P = .002), gastroscopy withdrawal (0% vs 2.29%; P = .008), and diaphragmatic pause at 30 seconds after propofol injection (74.5% vs 88.1%; RR, 0.846; 95% CI, 0.772-0.928; P < .001). In the therapeutic cohort, patients who received MMCC had a significantly shorter time spent below 95% Sp o2 (40 [20-69] seconds vs 91 [33-152] seconds, median difference [95% CI], -39 [-57 to -16] seconds, P < .001), a lower incidence of gastroscopy withdrawal (0% vs 10.4%, P = .018), and more enhanced diaphragmatic movement at 30 seconds after Sp o2 <95% (1.11 [0.93-1.4] cm vs 1.03 [0.7-1.24] cm; median difference [95% confidence interval], 0.16 [0.02-0.32] cm; P = .015). CONCLUSIONS: MMCC may exert preventive and therapeutic effects against oxygen desaturation events during upper gastrointestinal endoscopy.


Asunto(s)
Sedación Profunda , Propofol , Insuficiencia Respiratoria , Humanos , Sedación Consciente , Sedación Profunda/efectos adversos , Endoscopía Gastrointestinal/efectos adversos , Gastroscopía/efectos adversos , Oxígeno
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