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Donor-specific HLA antibody (DSA) has been recognised as an independent risk factor for graft failure in patients undergoing haploidentical haematopoietic stem cell transplantation (HID HSCT). Therapeutic plasma exchange (TPE), as a first-line strategy for DSA desensitisation, can promptly reduce serum DSA levels. This study aimed to investigate DSA characteristics and identify a biomarker predicting the efficacy of DSA desensitisation in patients proceeding to HID HSCT. We retrospectively enrolled 32 patients with DSA from April 2021 to January 2024, and analysed the mean fluorescence intensity (MFI) value of DSA at the different time points of desensitisation treatment. Compared with baseline DSA level before TPE, the median MFI of HLA class I DSA was reduced from 8178.6 to 795.3 (p < 0.001), and HLA class II DSA decreased from 6210.9 to 808.8 (p < 0.001) after TPE. The DSA level in 1:16 diluted pre-TPE serum correlated well with DSA value in post-TPE serum (class I, r = 0.85, p < 0.0001; class II, r = 0.94, p < 0.0001), predicting TPE efficacy in 84.4% of patients. Based on the degree of DSA reduction after TPE, patients were divided into complete responders (decreased by >70%), partial responders (decreased by 30 to 70%) and non-responders (decreased by <30%) and the percentages were 43.8%, 25% and 31.2%, respectively. Non-responders receiving aggressive immunotherapy had longer overall survival compared to those receiving standard strategies (p < 0.05). The 1:16 diluted pre-TPE serum may predict the efficacy of TPE and allow for more rational immunotherapy strategy for patients with DSA proceeding to HID HSCT.
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Antígenos HLA , Transplante de Células-Tronco Hematopoéticas , Isoanticorpos , Humanos , Transplante de Células-Tronco Hematopoéticas/métodos , Masculino , Feminino , Adulto , Estudos Retrospectivos , Pessoa de Meia-Idade , Antígenos HLA/imunologia , Isoanticorpos/sangue , Isoanticorpos/imunologia , Doadores de Tecidos , Rejeição de Enxerto/imunologia , Troca Plasmática/métodos , Adolescente , Transplante Haploidêntico/métodos , Adulto Jovem , Biomarcadores/sangue , Dessensibilização Imunológica/métodosRESUMO
The glymphatic-lymphatic system is increasingly recognized as fundamental for the homeostasis of the brain milieu since it defines cerebral spinal fluid flow in the brain parenchyma and eliminates metabolic waste. Animal and human studies have uncovered several important physiological factors regulating the glymphatic system including sleep, aquaporin-4, and hemodynamic factors. Yet, our understanding of the modulation of the glymphatic system is limited, which has hindered the development of glymphatic-based treatment for aging and neurodegenerative disorders. Here, we present the evidence from fluorescence tracing, two-photon recording, and dynamic contrast-enhanced magnetic resonance imaging analyses that 40 Hz light flickering enhanced glymphatic influx and efflux independently of anesthesia and sleep, an effect attributed to increased astrocytic aquaporin-4 polarization and enhanced vasomotion. Adenosine-A2A receptor (A2AR) signaling emerged as the neurochemical underpinning of 40 Hz flickering-induced enhancement of glymphatic flow, based on increased cerebrofluid adenosine levels, the abolishment of enhanced glymphatic flow by pharmacological or genetic inactivation of equilibrative nucleotide transporters-2 or of A2AR, and by the physical and functional A2AR-aquaporin-4 interaction in astrocytes. These findings establish 40 Hz light flickering as a novel non-invasive strategy of enhanced glymphatic flow, with translational potential to relieve brain disorders.
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Protein C (PC), a vitamin K-dependent serine protease zymogen in plasma, can be activated by thrombin-thrombomodulin(TM) complex, resulting in the formation of activated protein C (APC). APC functions to downregulate thrombin generation by inactivating active coagulation factors V(FVa) and VIII(FVIIIa). Deficiency in PC increases the risk of venous thromboembolism (VTE). We have identified two unrelated VTE patients with the same heterozygous mutation (c.1384 T > C, p.Ter462GlnextTer17) in PROC. To comprehend the role of this mutation in VTE development, we expressed recombinant PC-Ter462GlnextTer17 in mammalian cells and evaluated its characteristics using established coagulation assay systems. Functional studies revealed a significant impairment in the activation of the mutant by thrombin or thrombin-TM complex. Furthermore, APC-Ter462GlnextTer17 demonstrated diminished hydrolytic activity towards the chromogenic substrate S2366. APTT and FVa degradation assays showed that both the anticoagulant activity of the mutant protein was markedly impaired, regardless of whether protein S was present or absent. These results were further supported by a thrombin generation assay conducted using purified and plasma-based systems. In conclusion, the Ter462GlnextTer17 mutation introduces a novel tail at the C-terminus of PC, leading to impaired activity in both PC zymogen activation and APC's anticoagulant function. This impairment contributes to thrombosis in individuals carrying this heterozygous mutation and represents a genetic risk factor for VTE.
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Mutação , Proteína C , Trombose Venosa , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Proteína C/metabolismo , Proteína C/genética , Trombose Venosa/genéticaRESUMO
Obstructive sleep apnea, typically characterized by chronic intermittent hypoxia (CIH), is linked to cognitive dysfunction in children. Ferroptosis, a novel form of cell death characterized by lethal iron accumulation and lipid peroxidation, is implicated in neurodegenerative diseases and ischemia-reperfusion injuries. Nevertheless, its contribution to CIH-induced cognitive dysfunction and its interaction with endoplasmic reticulum stress (ERS) remain uncertain. In this study, utilizing a CIH model in 4-week-old male mice, we investigated ferroptosis and its potential involvement in ERS regulation during cognitive dysfunction. Our findings indicate ferroptosis activation in prefrontal cortex neurons, leading to neuron loss, mitochondrial damage, decreased levels of GPX4, SLC7A11, FTL, and FTH, increased levels of reactive oxygen species (ROS), malondialdehyde (MDA), Fe2+, ACSL4, TFRC, along with the activation of ERS-related PERK-ATF4-CHOP pathway. Treatment with the ferroptosis inhibitor liproxstatin-1 (Lip-1) and the iron chelator deferoxamine (DFO) effectively mitigated the neuron injury and cognitive dysfunction induced by CIH, significantly reducing Fe2+ and partly restoring expression levels of ferroptosis-related proteins. Furhermore, the use of Lip-1 and DFO downregulated p-PERK, ATF4 and CHOP, and upregulated Nrf2 expression, suggesting that inhibiting ferroptosis reduce ERS and that the transcription factor Nrf2 is involved in the process. In summary, our findings indicate that cognitive impairment in CIH mice correlates with the induction of neuronal ferroptosis, facilitated by the System xc - GPX4 functional axis, lipid peroxidation, and the iron metabolism pathway, along with ferroptosis-mediated ERS in the prefrontal cortex. Nrf2 has been identified as a potential regulator of ferroptosis and ERS involved in the context of CIH.
Assuntos
Disfunção Cognitiva , Estresse do Retículo Endoplasmático , Ferroptose , Hipóxia , Neurônios , Animais , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Masculino , Hipóxia/metabolismo , Hipóxia/complicações , Disfunção Cognitiva/etiologia , Disfunção Cognitiva/metabolismo , Neurônios/metabolismo , Neurônios/patologia , Camundongos , Camundongos Endogâmicos C57BL , Córtex Pré-Frontal/metabolismo , Córtex Pré-Frontal/patologia , Desferroxamina/farmacologia , Desferroxamina/uso terapêutico , Cicloexilaminas/farmacologia , Modelos Animais de Doenças , Espécies Reativas de Oxigênio/metabolismo , Apneia Obstrutiva do Sono/complicações , Apneia Obstrutiva do Sono/metabolismo , Humanos , Quinoxalinas , Compostos de Espiro , Sistema y+ de Transporte de AminoácidosRESUMO
OBJECTIVE: Obstructive Sleep Apnea (OSA) during pregnancy is characterized by intermittent hypoxia (IH) during sleep and will lead to the rise of oxidative stress in the fetal body. Pyroptosis, a type of inflammatory and programmable cell death mediated by Gasdermin D (GSDMD), plays a substantial role in oxygen deprivation's contribution to neural system damage. Existing research shows that Nicotinamide Adenine Dinucleotide Phosphate (NADPH) plays a protective role in alleviating brain tissue pyroptosis. We speculate that exogenous NADPH may play a protective role in OSA during pregnancy. METHODS: A model of GIH group was established to simulate the pathophysiological mechanisms of OSA during pregnant and AIR group was established by giving the same frequency. Sham group was established by injecting NS and the NADPH group was established and given exogenous NADPH. We utilized the Morris Water Maze to assess cognitive function impairment, Luxol Fast Blue (LBF) staining to confirm myelin sheath formation, TUNEL staining to examine cell death in fetal mice brain tissue, and Western blotting to detect pertinent protein expressions. RESULTS: The GIH group offspring exhibited decreases in spatial learning and memory abilities, reduced numbers of oligodendrocytes and formed myelin, as well as increased expression of pyroptosis-related proteins. The NADPH group offspring showed restoration in spatial learning and memory abilities increased counts of oligodendrocytes and formed myelin sheaths, in addition to decreased expression of pyroptosis-related. CONCLUSIONS: This study demonstrates that early injection of exogenous NADPH can alleviate the damage to fetal brain development caused by gestational intermittent hypoxia (GIH).
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NADP , Piroptose , Animais , Gravidez , Feminino , Camundongos , NADP/metabolismo , Lesões Encefálicas/patologia , Lesões Encefálicas/metabolismo , Hipóxia/metabolismo , Encéfalo/patologia , Encéfalo/metabolismo , Modelos Animais de Doenças , Masculino , Camundongos Endogâmicos C57BL , Efeitos Tardios da Exposição Pré-NatalRESUMO
Background: Drug-induced immune hemolytic anemia (DIIHA) is a rare but serious condition, with an estimated incidence of one in 100,000 cases, associated with various antibiotics. This study reports on a case of ceftizoxime-induced hemolysis observed in a patient in China. Case description: A Chinese patient diagnosed with malignant rectal cancer underwent antimicrobial therapy after laparoscopic partial recto-sigmoid resection (L-Dixon). After receiving four doses of ceftizoxime, the patient developed symptoms including rash, itchy skin, and chest distress, followed by a rapid decline in hemoglobin levels, the presence of hemoglobin in the urine (hemoglobinuria), renal failure, and disseminated intravascular coagulation. Laboratory analysis revealed high-titer antibodies against ceftizoxime and red blood cells (RBCs) in the patient's serum, including immunoglobulin M (IgM) (1:128) antibodies and immunoglobulin G (IgG) (1:8) antibodies, with noted crossreactivity to ceftriaxone. Significant improvement in the patient's hemolytic symptoms was observed following immediate discontinuation of the drug, two plasma exchanges, and extensive RBC transfusion. Conclusion: This case, together with previous reports, underscores the importance of considering DIIHA in patients who exhibit unexplained decreases in hemoglobin levels following antibiotic therapy. A thorough examination of the patient's medical history can provide crucial insights for diagnosing DIIHA. The effective management of DIIHA includes immediate cessation of the implicated drug, plasma exchange, and transfusion support based on the identification of specific drug-dependent antibodies through serological testing.
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Antibacterianos , Ceftizoxima , Hemoglobinas , Insuficiência de Múltiplos Órgãos , Neoplasias Retais , Humanos , Neoplasias Retais/tratamento farmacológico , Neoplasias Retais/imunologia , Neoplasias Retais/cirurgia , Hemoglobinas/metabolismo , Antibacterianos/efeitos adversos , Masculino , Ceftizoxima/efeitos adversos , Insuficiência de Múltiplos Órgãos/etiologia , Pessoa de Meia-Idade , Anemia Hemolítica/induzido quimicamente , Anemia Hemolítica/imunologia , Anemia Hemolítica/diagnóstico , Anemia Hemolítica/etiologia , Anemia Hemolítica Autoimune/induzido quimicamente , Anemia Hemolítica Autoimune/imunologia , Anemia Hemolítica Autoimune/diagnóstico , China , População do Leste AsiáticoRESUMO
OBJECTIVES: The study aimed to explore the underlying mechanisms of OSA-related cognitive impairment by investigating the altered topology of brain white matter networks in children with OSA. METHODS: Graph theory was used to examine white matter networks' network topological properties in 46 OSA and 31 non-OSA children. All participants underwent MRI, polysomnography, and cognitive testing. The effects of the obstructive apnea-hypopnea index (OAHI) on topological properties of white matter networks and network properties on cognition were studied using hierarchical linear regression. Mediation analyses were used to explore whether white matter network properties mediated the effects of OAHI on cognition. RESULTS: Children with OSA had significantly higher assortativity than non-OSA children. Furthermore, OAHI was associated with the nodal properties of several brain regions, primarily in the frontal and temporal lobes. The relationship between OAHI and verbal comprehension index was mediated through clustering coefficients in the right temporal pole of the superior temporal gyrus. CONCLUSIONS: OSA affects the development of white matter networks in children's brains. Besides, the mediating role of white matter network properties between the OAHI and the verbal comprehension index provided neuroimaging evidence of impaired cognitive function in children with OSA.
Assuntos
Imageamento por Ressonância Magnética , Polissonografia , Apneia Obstrutiva do Sono , Substância Branca , Humanos , Masculino , Apneia Obstrutiva do Sono/fisiopatologia , Apneia Obstrutiva do Sono/complicações , Substância Branca/diagnóstico por imagem , Substância Branca/patologia , Feminino , Criança , Cognição/fisiologia , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Testes Neuropsicológicos/estatística & dados numéricos , Disfunção Cognitiva/fisiopatologia , Disfunção Cognitiva/diagnóstico por imagem , Disfunção Cognitiva/etiologiaRESUMO
AST-001 is a chemically synthesized inactive nitrogen mustard prodrug that is selectively cleaved to a cytotoxic aziridine (AST-2660) via aldo-keto reductase family 1 member C3 (AKR1C3). The purpose of this study was to investigate the pharmacokinetics and tissue distribution of the prodrug, AST-001, and its active metabolite, AST-2660, in mice, rats, and monkeys. After single and once daily intravenous bolus doses of 1.5, 4.5, and 13.5 mg/kg AST-001 to Sprague-Dawley rats and once daily 1 h intravenous infusions of 0.5, 1.5, and 4.5 mg/kg AST-001 to cynomolgus monkeys, AST-001 exhibited dose-dependent pharmacokinetics and reached peak plasma levels at the end of the infusion. No significant accumulation and gender differences were observed after 7 days of repeated dosing. In rats, the half-life of AST-001 was dose independent and ranged from 4.89 to 5.75 h. In cynomolgus monkeys, the half-life of AST-001 was from 1.66 to 5.56 h and increased with dose. In tissue distribution studies conducted in Sprague-Dawley rats and in liver cancer PDX models in female athymic nude mice implanted with LI6643 or LI6280 HepG2-GFP tumor fragments, AST-001 was extensively distributed to selected tissues. Following a single intravenous dose, AST-001 was not excreted primarily as the prodrug, AST-001 or the metabolite AST-2660 in the urine, feces, and bile. A comprehensive analysis of the preclinical data and inter-species allometric scaling were used to estimate the pharmacokinetic parameters of AST-001 in humans and led to the recommendation of a starting dose of 5 mg/m2 in the first-in-human dose escalation study.
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Compostos de Mostarda Nitrogenada , Pró-Fármacos , Animais , Feminino , Camundongos , Ratos , Membro C3 da Família 1 de alfa-Ceto Redutase/efeitos dos fármacos , Macaca fascicularis , Camundongos Nus , Ratos Sprague-Dawley , Compostos de Mostarda Nitrogenada/farmacocinética , Aziridinas/farmacocinética , Relação Dose-Resposta a DrogaRESUMO
BACKGROUND: Kawasaki disease (KD) is a systemic vasculitis accompanied by many systemic physiological and biochemical changes. Elucidating its molecular mechanisms is crucial for diagnosing and developing effective treatments. NLR Family CARD Domain Containing 4 (NLRC4) encodes the key components of inflammasomes that function as pattern recognition receptors. The purpose of this study was to investigate the potential of NLRC4 methylation as a biomarker for KD. METHODS: In this study, pyrosequencing was utilized to analyze NLRC4 promoter methylation in blood samples from 44 children with initial complete KD and 51 matched healthy controls. Methylation at five CpG sites within the NLRC4 promoter region was evaluated. RESULTS: Compared to controls, NLRC4 methylation significantly decreased in KD patients (CpG1: p = 2.93E-06; CpG2: p = 2.35E-05; CpG3: p = 6.46E-06; CpG4: p = 2.47E-06; CpG5: p = 1.26E-05; average methylation: p = 5.42E-06). These changes were significantly reversed after intravenous immunoglobulin (IVIG) treatment. ROC curve analysis demonstrated remarkable diagnostic capability of mean NLRC4 gene methylation for KD (areas under ROC curve = 0.844, sensitivity = 0.75, p = 9.61E-06, 95% confidence intervals were 0.762-0.926 for mean NLRC4 methylation). In addition, NLRC4 promoter methylation was shown to be significantly negatively correlated with the levels of central granulocyte percentage, age, mean haemoglobin quantity and mean erythrocyte volume. Besides, NLRC4 promoter methylation was positively correlated with lymphocyte percentage, lymphocyte absolute value. CONCLUSIONS: Our work revealed the role of peripheral NLRC4 hypomethylation in KD pathogenesis and IVIG treatment response, could potentially serve as a treatment monitoring biomarker, although its precise functions remain to be elucidated.
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Imunoglobulinas Intravenosas , Síndrome de Linfonodos Mucocutâneos , Criança , Humanos , Imunoglobulinas Intravenosas/uso terapêutico , Estudos de Casos e Controles , Síndrome de Linfonodos Mucocutâneos/diagnóstico , Síndrome de Linfonodos Mucocutâneos/tratamento farmacológico , Síndrome de Linfonodos Mucocutâneos/genética , Metilação de DNA , Biomarcadores , Proteínas de Ligação ao Cálcio/genética , Proteínas Adaptadoras de Sinalização CARD/genéticaRESUMO
Flickering light stimulation has emerged as a promising non-invasive neuromodulation strategy to alleviate neuropsychiatric disorders. However, the lack of a neurochemical underpinning has hampered its therapeutic development. Here, we demonstrate that light flickering triggered an immediate and sustained increase (up to 3 h after flickering) in extracellular adenosine levels in the primary visual cortex (V1) and other brain regions, as a function of light frequency and intensity, with maximal effects observed at 40 Hz frequency and 4000 lux. We uncovered cortical (glutamatergic and GABAergic) neurons, rather than astrocytes, as the cellular source, the intracellular adenosine generation from AMPK-associated energy metabolism pathways (but not SAM-transmethylation or salvage purine pathways), and adenosine efflux mediated by equilibrative nucleoside transporter-2 (ENT2) as the molecular pathway responsible for extracellular adenosine generation. Importantly, 40 Hz (but not 20 and 80 Hz) light flickering for 30 min enhanced non-rapid eye movement (non-REM) and REM sleep for 2-3 h in mice. This somnogenic effect was abolished by ablation of V1 (but not superior colliculus) neurons and by genetic deletion of the gene encoding ENT2 (but not ENT1), but recaptured by chemogenetic inhibition of V1 neurons and by focal infusion of adenosine into V1 in a dose-dependent manner. Lastly, 40 Hz light flickering for 30 min also promoted sleep in children with insomnia by decreasing sleep onset latency, increasing total sleep time, and reducing waking after sleep onset. Collectively, our findings establish the ENT2-mediated adenosine signaling in V1 as the neurochemical basis for 40 Hz flickering-induced sleep and unravel a novel and non-invasive treatment for insomnia, a condition that affects 20% of the world population.
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Distúrbios do Início e da Manutenção do Sono , Humanos , Criança , Animais , Camundongos , Sono , Transdução de Sinais , Adenosina , AstrócitosRESUMO
HLA-B*48:01:13 differs from HLA-B*48:01:01:01 by one nucleotide in exon 5.
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Antígenos HLA-B , Nucleotídeos , Humanos , Alelos , Análise de Sequência de DNA , Antígenos HLA-B/genética , ChinaRESUMO
BACKGROUND: The dysfunction of the ABO glycosyltransferase (GT) enzyme, which is caused by mutations in the ABO gene, can lead to weak ABO phenotypes. In this study, we have discovered a novel weak ABO subgroup allele and investigated the underlying mechanism to causing its Aweak phenotype. MATERIALS AND METHODS: The ABO phenotyping and genotyping were performed by serological studies and direct DNA sequencing of ABO gene. The role of the novel single nucleotide polymorphism (SNP) was evaluated by 3D model, predicting protein structure changes, and in vitro expression assay. The total glycosyltransferase transfer capacity in supernatant of transfected cells was examined. RESULTS: The results of serological showed the subject was Aweak phenotype. A novel SNP c.424A > G (p. M142V) based on ABO*A1.02 was identified, and the genotype of the subject was AW-var/O.01 according to the gene analysis. In silico analysis showed that the SNP c.424A > G on the A allele may change the local conformation by damaging the hydrogen bonds and reduce the stability of GT. In vitro expression study showed that SNP p.M142V impaired H to A antigen conversion, although it did not affect the generation of A glycosyltransferase (GTA). CONCLUSIONS: One novel AW allele was identified and the SNP c.424A > G (p.M142V) can cause the Aweak phenotype through damaging the hydrogen bonds and reducing stability of the GTA.
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BACKGROUND: Fruquintinib has demonstrated significant improvement in overall survival (OS) among previously treated metastatic colorectal cancer (mCRC) patients. However, the utilization of fruquintinib has been constrained by various toxicities, such as hand-foot skin reaction (HFSR) and hypertension, particularly in elderly patients with reduced tolerance to the standard dosage. This study aims to investigate the efficacy and safety of fruquintinib dose-escalation strategy for elderly refractory mCRC patients. PATIENTS AND METHODS: This open-label, single-arm, phase II trial included patients aged 65 years or over with mCRC who had progressed after two or more lines of chemotherapy. Fruquintinib was administered for 21 consecutive days of a 28-day treatment cycle. The starting dose of fruquintinib was 3 mg/day and escalated to 4 mg/day in Week 2 and 5 mg/day in Week 3 if no significant drug-related toxicity was observed. The highest tolerated dose from Cycle 1 would be administered in Cycle 2 and all subsequent cycles. Before commencing treatment, all enrolled patients underwent a G8 questionnaire and comprehensive geriatric assessments. The primary endpoint of the study was progression-free survival (PFS). RESULTS: A total of 29 patients were enrolled and all started fruquintinib at 3 mg/day. Fifteen patients (51.7%) were subsequently escalated to 4 mg/day and 4 (13.8%) to 5 mg/day. Only four (13.8%) patients discontinued treatment due to adverse events (AEs). The median PFS was 3.8 months (95% CI, 2.7-4.9), and the median OS was 7.6 months (95% CI, 6.5-8.7). Treatment-related adverse events (TRAEs) were observed in all 29 patients (100%). The most frequently occurring (>10%) TRAEs greater than Grade 3 were HFSR (20.7%), hypertension (20.7%), and diarrhea (10.3%). CONCLUSION: Our study indicated that a dose of 4 mg/day was well tolerated by most elderly patients, suggesting that fruquintinib dose-escalation strategy during the first cycle could serve as a viable alternative to the standard 5 mg/day dosing.
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Benzofuranos , Neoplasias do Colo , Neoplasias Colorretais , Hipertensão , Neoplasias Retais , Idoso , Humanos , Neoplasias Colorretais/patologia , Neoplasias do Colo/tratamento farmacológico , Benzofuranos/efeitos adversos , Neoplasias Retais/tratamento farmacológico , Hipertensão/induzido quimicamente , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêuticoRESUMO
BACKGROUND AND OBJECTIVES: ABO antigens are produced from H antigen by the activity of glycosyltransferase enzyme encoded by the ABO gene. Variants in the ABO gene can produce a weak ABO phenotype. In this study, we identify a novel ABO*BW allele and investigate the underlying mechanism leading to the Bweak phenotype. MATERIALS AND METHODS: The ABO phenotype and genotype of the sample were determined using serological and direct DNA sequencing methods. We assessed the impact of the novel variant by three-dimensional modelling to predict protein stability changes (ΔΔG), and carried out an in vitro expression assay. The total glycosyltransferase transfer capacity in the supernatant of transfected cells was also examined. RESULTS: Serological analysis confirmed the Bweak phenotype in the subject, and gene sequencing identified a novel variant c.761C>T (p.A254V) on the ABO*B.01 allele, resulting in a BW-var/O.01.02 genotype. In silico analysis suggested that the p.A254V variant on the B allele may reduce the stability of glycosyltransferase B (GTB), as indicated by the ΔΔG values. In vitro expression studies showed that the variant p.A254V impaired H to B antigen conversion, although it did not affect the expression of GTB. CONCLUSION: We identified a novel BW allele and demonstrated that the variant c.761C>T (p.A254V) can cause the Bweak phenotype by reducing the stability of GTB.
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Obstructive sleep apnea-hypopnea syndrome (OSAHS) is involved in cognitive impairment of children. Chronic intermittent hypoxia (CIH) is considered as the critical pathophysiological mechanism of OSAHS. Calcium sensitive receptor (CaSR) mediated apoptosis in many neurological disease models by endoplasmic reticulum stress (ERS)-related pathway. However, little is known about the role of CaSR in OSAHS-induced cognitive dysfunction. In this study, we explored the effect of CaSR on CIH-induced cognitive impairment and possible mechanisms on regulation of PERK-ATF4-CHOP pathway in vivo and in vitro. CIH exposed for 9 h in PC12 cells and resulted in the cell apoptosis, simulating OSAHS-induced neuronal injury. CIH upregulated the level of CaSR, p-PERK, ATF4 and CHOP, contributing to the cell apoptosis. Treated with CaSR inhibitor (NPS-2143) or p-PERK inhibitor (GSK2656157) before CIH exposure, CIH-induced PC12 cell apoptosis was alleviated via inhibition of CaSR by downregulating p-PERK, ATF4 and CHOP. In addition, we established CIH mice model. With CIH exposure for 4 weeks in mice, more spatial memory errors were observed during 8-arm radial maze test. CIH significantly increased apoptotic cells in hippocampus via upregulating cleaved Caspase-3 and downregulating ratio of Bcl-2 to Bax. Besides, treatment of CaSR inhibitor alleviated the hippocampal neuronal apoptosis following CIH with downregulated p-PERK, ATF4 and CHOP, suggesting that CaSR contributed to CIH-induced neuronal apoptosis in hippocampus via ERS pathway. Sum up, our results demonstrated that CaSR accelerated hippocampal apoptosis via PERK-ATF4-CHOP pathway, holding a critical function on CIH-mediated cognitive impairment. Conversely, inhibition of CaSR suppressed PERK-ATF4-CHOP pathway and alleviated cognitive impairment.
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Disfunção Cognitiva , Apneia Obstrutiva do Sono , Ratos , Camundongos , Animais , Receptores de Detecção de Cálcio , Hipóxia , Disfunção Cognitiva/tratamento farmacológico , Disfunção Cognitiva/etiologia , Modelos Animais de Doenças , Apoptose , Estresse do Retículo EndoplasmáticoRESUMO
Background: We investigated the expression and the potential value of plasma transfer RNA-derived fragments (tRFs) of children with obstructive sleep apnea-hypopnea syndrome (OSAHS) as screening biomarkers. Methods: At first, we randomly selected five plasma samples from the case group and the control group for high-throughput RNA sequencing. Secondly, we screened two tRFs with different expression between the two groups, amplified it by quantitative reverse transcription-PCR (qRT-PCR) on all samples. Then we analyzed the diagnostic value of the tRFs and their correlation with the clinical data. Results: A total of 50 OSAHS children and 38 healthy controls were included. Our results demonstrated that the plasma levels of tRF-16-79MP9PD and tRF-28-OB1690PQR304 were significantly down-regulated in OSAHS children. Receiver operating characteristic curve (ROC) showed that the area under the curve (AUC) of tRF-16-79MP9PD and tRF-28-OB1690PQR304 was 0.7945 and 0.8276. In addition, the AUC of the combination reached 0.8303 with 73.46% and 76.42% sensitivity and specificity. Correlation analysis showed that the degree of tonsil enlargement, hemoglobin (Hb) and triglyceride (TG). were related to the expression levels of tRF-16-79MP9PD and tRF-28-OB1690PQR304. Multivariable linear regression analysis showed that degree of tonsil enlargement, Hb and TG related to tRF-16-79MP9PD while degree of tonsil enlargement and Hb related to tRF-28-OB1690PQR304. Conclusions: The expression levels of tRF-16-79MP9PD and tRF-28-OB1690PQR304 in the plasma of OSAHS children decreased significantly which were closely related to the degree of tonsil enlargement, Hb and TG, may become novel biomarkers for the diagnosis of pediatric OSAHS.
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HLA-B*40:536N differs from HLA-B*40:03:01:01 by one nucleotide in exon 3.
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População do Leste Asiático , Antígenos HLA-B , Humanos , Alelos , Análise de Sequência de DNA , Antígenos HLA-B/genética , NucleotídeosRESUMO
HLA-B*51:381 differs from HLA-B*51:01:01:01 by one nucleotide in exon 5.
Assuntos
Antígenos HLA-B , Humanos , Alelos , População do Leste Asiático/genética , Antígenos HLA-B/genética , Nucleotídeos , Análise de Sequência de DNARESUMO
Objective: Obstructive sleep apnea (OSA) seriously affects the children's cognitive functions, but the neuroimaging mechanism of cognitive impairment is still unclear. The purpose of our study was to explore the difference in brain local gray matter volume (GMV) between children with OSA and non-OSA, and the correlation between the difference regions of brain gray matter volume and cognitive, the severity of OSA. Method: Eighty-three children aged 8-13 years were recruited in our study, 52 children were diagnosed as OSA by polysomnography, and 31 as the non-OSA. All the subjects were underwent high-resolution 3-dimensional T1-weighted magnetic resonance images. The voxel-based morphometry (VBM) was be used to analyse the local GMV. The Das-Naglieri cognitive assessment system (DN: CAS) was used to assess the subjects' cognitive. The difference of local GMV between the two groups was analyzed by two-sample T-test. The PSG variables and the scores of DN: CAS between the OSA group and non-OSA group were compared by independent samples t-tests. Pearson correlation was used to calculate the association between the difference areas of gray matter volumes in brain and DN: CAS scores, obstructive apnea/hypopnea index (OAHI, an index of the severity of OSA). Results: The gray matter volume of the right Middle Frontal Gyrus (MFG_R) in OSA children were larger than the non-OSA children, and the OSA children had lower scores of the Word Series in DN: CAS. There was negative correlation between the scores of Expressive Attention in DN: CAS and the gray matter volume of the right middle frontal gyrus, and it was no significantly correlation between OAHI and the gray matter volume of the right middle frontal gyrus. Conclusion: Our results suggest that the development of gray matter volume in frontal cortex, which associated with attention, were sensitive to the effects of OSA, provides neuroimaging evidence for cognitive impairment in children with OSA.