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1.
Cell ; 154(5): 1112-1126, 2013 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-23993099

RESUMO

Consensus holds that hematopoietic stem cells (HSCs) give rise to multipotent progenitors (MPPs) of reduced self-renewal potential and that MPPs eventually produce lineage-committed progenitor cells in a stepwise manner. Using a single-cell transplantation system and marker mice, we unexpectedly found myeloid-restricted progenitors with long-term repopulating activity (MyRPs), which are lineage-committed to megakaryocytes, megakaryocyte-erythroid cells, or common myeloid cells (MkRPs, MERPs, or CMRPs, respectively) in the phenotypically defined HSC compartment together with HSCs. Paired daughter cell assays combined with transplantation revealed that HSCs can give rise to HSCs via symmetric division or directly differentiate into MyRPs via asymmetric division (yielding HSC-MkRP or HSC-CMRP pairs). These myeloid bypass pathways could be essential for fast responses to ablation stress. Our results show that loss of self-renewal and stepwise progression through specific differentiation stages are not essential for lineage commitment of HSCs and suggest a revised model of hematopoietic differentiation.


Assuntos
Células-Tronco Hematopoéticas/citologia , Células Progenitoras Mieloides/citologia , Animais , Antígenos CD34 , Hematopoese , Células-Tronco Hematopoéticas/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Células Progenitoras Mieloides/metabolismo
2.
Blood ; 143(3): 243-257, 2024 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-37922454

RESUMO

ABSTRACT: Regulation of lineage biases in hematopoietic stem and progenitor cells (HSPCs) is pivotal for balanced hematopoietic output. However, little is known about the mechanism behind lineage choice in HSPCs. Here, we show that messenger RNA (mRNA) decay factors regnase-1 (Reg1; Zc3h12a) and regnase-3 (Reg3; Zc3h12c) are essential for determining lymphoid fate and restricting myeloid differentiation in HSPCs. Loss of Reg1 and Reg3 resulted in severe impairment of lymphopoiesis and a mild increase in myelopoiesis in the bone marrow. Single-cell RNA sequencing analysis revealed that Reg1 and Reg3 regulate lineage directions in HSPCs via the control of a set of myeloid-related genes. Reg1- and Reg3-mediated control of mRNA encoding Nfkbiz, a transcriptional and epigenetic regulator, was essential for balancing lymphoid/myeloid lineage output in HSPCs in vivo. Furthermore, single-cell assay for transposase-accessible chromatin sequencing analysis revealed that Reg1 and Reg3 control the epigenetic landscape on myeloid-related gene loci in early stage HSPCs via Nfkbiz. Consistently, an antisense oligonucleotide designed to inhibit Reg1- and Reg3-mediated Nfkbiz mRNA degradation primed hematopoietic stem cells toward myeloid lineages by enhancing Nfkbiz expression. Collectively, the collaboration between posttranscriptional control and chromatin remodeling by the Reg1/Reg3-Nfkbiz axis governs HSPC lineage biases, ultimately dictating the fate of lymphoid vs myeloid differentiation.


Assuntos
Medula Óssea , Células-Tronco Hematopoéticas , Linhagem da Célula/genética , Células-Tronco Hematopoéticas/metabolismo , Medula Óssea/metabolismo , Hematopoese/genética , RNA Mensageiro/metabolismo , Diferenciação Celular/genética
3.
Nature ; 571(7766): E12, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31289376

RESUMO

An Amendment to this paper has been published and can be accessed via a link at the top of the paper.

4.
Nature ; 571(7763): 117-121, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31142833

RESUMO

Multipotent self-renewing haematopoietic stem cells (HSCs) regenerate the adult blood system after transplantation1, which is a curative therapy for numerous diseases including immunodeficiencies and leukaemias2. Although substantial effort has been applied to identifying HSC maintenance factors through the characterization of the in vivo bone-marrow HSC microenvironment or niche3-5, stable ex vivo HSC expansion has previously been unattainable6,7. Here we describe the development of a defined, albumin-free culture system that supports the long-term ex vivo expansion of functional mouse HSCs. We used a systematic optimization approach, and found that high levels of thrombopoietin synergize with low levels of stem-cell factor and fibronectin to sustain HSC self-renewal. Serum albumin has long been recognized as a major source of biological contaminants in HSC cultures8; we identify polyvinyl alcohol as a functionally superior replacement for serum albumin that is compatible with good manufacturing practice. These conditions afford between 236- and 899-fold expansions of functional HSCs over 1 month, although analysis of clonally derived cultures suggests that there is considerable heterogeneity in the self-renewal capacity of HSCs ex vivo. Using this system, HSC cultures that are derived from only 50 cells robustly engraft in recipient mice without the normal requirement for toxic pre-conditioning (for example, radiation), which may be relevant for HSC transplantation in humans. These findings therefore have important implications for both basic HSC research and clinical haematology.


Assuntos
Técnicas de Cultura de Células/métodos , Autorrenovação Celular/efeitos dos fármacos , Transplante de Células-Tronco Hematopoéticas/métodos , Células-Tronco Hematopoéticas/citologia , Animais , Proliferação de Células/efeitos dos fármacos , Células Clonais/citologia , Células Clonais/efeitos dos fármacos , Meios de Cultura/química , Meios de Cultura/farmacologia , Feminino , Fibronectinas/farmacologia , Células-Tronco Hematopoéticas/efeitos dos fármacos , Masculino , Camundongos , Álcool de Polivinil/farmacologia , Albumina Sérica , Fator de Células-Tronco/farmacologia , Trombopoetina/farmacologia , Fatores de Tempo , Condicionamento Pré-Transplante
5.
Biochem Biophys Res Commun ; 693: 149355, 2024 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-38096617

RESUMO

Nardilysin (NRDC) is a multifunctional protein required for maintaining homeostasis in various cellular and tissue contexts. However, its role in hematopoietic stem cells (HSCs) remains unclear. Here, through the conditional deletion of NRDC in hematopoietic cells, we demonstrate that NRDC is required for HSCs expansion in vitro and the reconstitution of hematopoiesis in vivo after transplantation. We found NRDC-deficient HSCs lose their self-renewal ability and display a preferential bias to myeloid differentiation in response to replication stress. Transcriptome data analysis revealed the upregulation of heat shock response-related genes in NRDC-deficient HSCs. Additionally, we observed increased protein synthesis in cultured NRDC-deficient HSCs. Thus, loss of NRDC may cause the inability to control protein synthesis in response to replication induced protein stress, leading to the impaired HSC self-renewal ability. This highlights a novel model of action of NRDC specifically in HSCs.


Assuntos
Células-Tronco Hematopoéticas , Metaloendopeptidases , Células-Tronco Hematopoéticas/metabolismo , Metaloendopeptidases/metabolismo , Hematopoese/fisiologia , Regulação para Cima , Diferenciação Celular/genética
6.
Bioinformatics ; 39(11)2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-37871161

RESUMO

MOTIVATION: Double-stranded RNAs (dsRNAs) are potent triggers of innate immune responses upon recognition by cytosolic dsRNA sensor proteins. Identification of endogenous dsRNAs helps to better understand the dsRNAome and its relevance to innate immunity related to human diseases. RESULTS: Here, we report dsRID (double-stranded RNA identifier), a machine-learning-based method to predict dsRNA regions in silico, leveraging the power of long-read RNA-sequencing (RNA-seq) and molecular traits of dsRNAs. Using models trained with PacBio long-read RNA-seq data derived from Alzheimer's disease (AD) brain, we show that our approach is highly accurate in predicting dsRNA regions in multiple datasets. Applied to an AD cohort sequenced by the ENCODE consortium, we characterize the global dsRNA profile with potentially distinct expression patterns between AD and controls. Together, we show that dsRID provides an effective approach to capture global dsRNA profiles using long-read RNA-seq data. AVAILABILITY AND IMPLEMENTATION: Software implementation of dsRID, and genomic coordinates of regions predicted by dsRID in all samples are available at the GitHub repository: https://github.com/gxiaolab/dsRID.


Assuntos
Genoma , RNA de Cadeia Dupla , Humanos , RNA-Seq , Análise de Sequência de RNA , Sequência de Bases , Software
7.
BMC Musculoskelet Disord ; 25(1): 314, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38654188

RESUMO

BACKGROUND: The role of lactate level in selecting the timing of definitive surgery for isolated extremity fracture remains unclear. Therefore, we aimed to elucidate the use of preoperative lactate level for predicting early postoperative complications. METHODS: This was a single-center retrospective observational study of patients with isolated extremity fracture who underwent orthopedic surgery. Patients who underwent lactate level assessment within 24 h prior to surgery were included. The incidence of early postoperative complications was compared between patients with a preoperative lactate level of ≥ 2 and < 2 mmol/L. Moreover, subgroup analyses were performed based on the time from hospital arrival to surgery and fracture type. RESULTS: In total, 187 patients were included in the study. The incidence of postoperative complications was significantly higher in patients with a preoperative lactate level of ≥ 2 mmol/L than those with a preoperative lactate level of < 2 mmol/L. This result did not change after adjusting for age and severity. Further, a high preoperative lactate level was associated with a greater incidence of postoperative complications in patients who underwent definitive surgery within 6 h after arrival. CONCLUSION: A preoperative lactate level of ≥ 2 mmol/L was associated with a greater incidence of early postoperative complications in isolated extremity fractures. Nevertheless, this correlation was only observed among patients who underwent definitive fixation within 6 h after hospital arrival.


Assuntos
Fraturas Ósseas , Ácido Láctico , Complicações Pós-Operatórias , Humanos , Masculino , Feminino , Estudos Retrospectivos , Pessoa de Meia-Idade , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/sangue , Complicações Pós-Operatórias/diagnóstico , Ácido Láctico/sangue , Idoso , Adulto , Fraturas Ósseas/cirurgia , Fraturas Ósseas/sangue , Fraturas Ósseas/epidemiologia , Incidência , Fatores de Tempo , Período Pré-Operatório , Biomarcadores/sangue
8.
Pediatr Int ; 66(1): e15767, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38924178

RESUMO

BACKGROUND: Twin pregnancies are associated with a high risk of perinatal mortality and morbidity. Late preterm or early term delivery is frequently performed to avoid unexpected fetal death in uncomplicated twin pregnancies. Nonetheless, delivery before full term is associated with neonatal respiratory complications. This study aimed to evaluate perinatal respiratory complications in twins delivered between 36 and 38 weeks of gestation. METHODS: A retrospective cohort study was conducted on twins delivered between 36 and 38 weeks of gestation from January 2008 to June 2020. The primary outcomes were the incidence of composite neonatal respiratory morbidity, which included respiratory distress syndrome, transient tachypnea of the newborn, meconium aspiration syndrome, mechanical ventilation or continuous positive airway pressure according to gestational age at delivery, and chorionicity. The relationship between gestational age at delivery and composite neonatal respiratory morbidity was evaluated using multivariate logistic regression analysis adjusted for potential confounders. RESULTS: This study included 1608 twins (614 monochorionic diamniotic twins, 994 dichorionic diamniotic twins). At 36, 37, and 38 weeks of gestation, the frequencies of composite neonatal respiratory morbidity were 19.4%, 10.7%, and 9.2% in dichorionic diamniotic twins and 13.6%, 8.7%, and 9.4% in monochorionic diamniotic twins, respectively. In dichorionic diamniotic twins, the composite neonatal respiratory morbidity rate was higher for twins delivered at 36 weeks of gestation than for those delivered at 37 weeks. No significant differences between monochorionic diamniotic twins were detected. CONCLUSIONS: In uncomplicated dichorionic diamniotic twin pregnancies, delivery should be considered after 37 weeks of gestation to reduce neonatal respiratory complications.


Assuntos
Idade Gestacional , Gravidez de Gêmeos , Síndrome do Desconforto Respiratório do Recém-Nascido , Humanos , Recém-Nascido , Feminino , Estudos Retrospectivos , Gravidez , Síndrome do Desconforto Respiratório do Recém-Nascido/epidemiologia , Síndrome do Desconforto Respiratório do Recém-Nascido/etiologia , Masculino , Taquipneia Transitória do Recém-Nascido/epidemiologia , Síndrome de Aspiração de Mecônio/epidemiologia , Incidência , Respiração Artificial , Pressão Positiva Contínua nas Vias Aéreas , Gêmeos
9.
Sensors (Basel) ; 24(10)2024 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-38794075

RESUMO

The recent rapid growth in Internet of Things (IoT) technologies is enriching our daily lives but significant information security risks in IoT fields have become apparent. In fact, there have been large-scale botnet attacks that exploit undiscovered vulnerabilities, known as zero-day attacks. Several intrusion detection methods based on network traffic monitoring have been proposed to address this issue. These methods employ federated learning to share learned attack information among multiple IoT networks, aiming to improve collective detection capabilities against attacks including zero-day attacks. Although their ability to detect zero-day attacks with high precision has been confirmed, challenges such as autonomous labeling of attacks from traffic information and attack information sharing between different device types still remain. To resolve the issues, this paper proposes IDAC, a novel intrusion detection method with autonomous attack candidate labeling and federated learning-based attack candidate sharing. The labeling of attack candidates in IDAC is executed using information autonomously extracted from traffic information, and the labeling can also be applied to zero-day attacks. The federated learning-based attack candidate sharing enables candidate aggregation from multiple networks, and it executes attack determination based on the aggregated similar candidates. Performance evaluations demonstrated that IDS with IDAC within networks based on attack candidates is feasible and achieved comparable detection performance against multiple attacks including zero-day attacks compared to the existing methods while suppressing false positives in the extraction of attack candidates. In addition, the sharing of autonomously extracted attack candidates from multiple networks improves both detection performance and the required time for attack detection.

10.
BMC Gastroenterol ; 23(1): 108, 2023 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-37020263

RESUMO

BACKGROUND: Intestinal microinflammation with immune dysfunction due to severe acute respiratory syndrome coronavirus 2 reportedly precipitates post-infectious irritable bowel syndrome. This study aimed to elucidate potential risk factors for subsequent development of irritable bowel syndrome, hypothesizing that it is associated with specific symptoms or patient backgrounds. METHODS: This single-center retrospective observational study (2020-2021) included adults with confirmed coronavirus disease requiring hospital admission and was conducted using real-world data retrieved from a hospital information system. Patient characteristics and detailed gastrointestinal symptoms were obtained and compared between patients with and without coronavirus disease-induced irritable bowel syndrome. Multivariate logistic models were used to validate the risk of developing irritable bowel syndrome. Moreover, daily gastrointestinal symptoms during hospitalization were examined in patients with irritable bowel syndrome. RESULTS: Among the 571 eligible patients, 12 (2.1%) were diagnosed with irritable bowel syndrome following coronavirus disease. While nausea and diarrhea during hospitalization, elevated white blood cell count on admission, and intensive care unit admission were associated with the development of irritable bowel syndrome, nausea and diarrhea were identified as risk factors for its development following coronavirus disease, as revealed by the adjusted analyses (odds ratio, 4.00 [1.01-15.84] and 5.64 [1.21-26.31], respectively). Half of the patients with irritable bowel syndrome had both diarrhea and constipation until discharge, and constipation was frequently followed by diarrhea. CONCLUSIONS: While irritable bowel syndrome was rarely diagnosed following coronavirus disease, nausea and diarrhea during hospitalization precede the early signs of irritable bowel syndrome following coronavirus disease.


Assuntos
COVID-19 , Gastroenteropatias , Síndrome do Intestino Irritável , Adulto , Humanos , Síndrome do Intestino Irritável/complicações , COVID-19/complicações , Gastroenteropatias/complicações , Constipação Intestinal/diagnóstico , Diarreia/etiologia , Náusea
11.
Ann Emerg Med ; 82(1): 84-93, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36964008

RESUMO

STUDY OBJECTIVE: To elucidate the clinical utility of the Clinical Frailty Scale score for predicting poor neurologic functions in patients resuscitated from out-of-hospital cardiac arrest (OHCA). METHODS: This was a prospective, multicenter, observational study conducted between 2019 and 2021. The study included adults with nontraumatic OHCA admitted to the intensive care unit after return of spontaneous circulation (ROSC). Pre-arrest high Clinical Frailty Scale score was defined as 5 or more. Favorable neurologic outcomes defined as a Cerebral Performance Category score of 2 or less at 30 days after admission were compared between patients with and without high Clinical Frailty Scale scores. Multivariable logistic regression analyses fitted with generalized estimating equations were performed to adjust for patient characteristics, out-of-hospital information, and resuscitation content and account for within-institution clustering. RESULTS: Of 9,909 patients with OHCA during the study period, 1,216 were included, and 317 had a pre-arrest high Clinical Frailty Scale score. Favorable neurologic outcomes were fewer among patients with high Clinical Frailty Scale scores. The high Clinical Frailty Scale score group showed a lower percentage of favorable neurologic outcomes after OHCA than the low Clinical Frailty Scale score group (6.1% vs 24.4%; adjusted odds ratio, 0.45 [95% confidence interval 0.22 to 0.93]). This relationship remained in subgroups with cardiogenic OHCA, with ROSC after hospital arrival, and without a high risk of dying (Clinical Frailty Scale score of 7 or less), whereas the neurologic outcomes were comparable regardless of pre-arrest frailty in those with noncardiogenic OHCA and with ROSC before hospital arrival. CONCLUSIONS: Pre-arrest high Clinical Frailty Scale score was associated with unfavorable neurologic functions among patients resuscitated from OHCA. The Clinical Frailty Scale score would help predict clinical consequences following intensive care after ROSC.


Assuntos
Reanimação Cardiopulmonar , Fragilidade , Parada Cardíaca Extra-Hospitalar , Adulto , Humanos , Parada Cardíaca Extra-Hospitalar/terapia , Estudos Prospectivos , Hospitalização
12.
Crit Care ; 27(1): 131, 2023 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-37005646

RESUMO

BACKGROUND: Supraphysiologic oxygen administration causes unfavorable clinical outcomes in various diseases, including traumatic brain injury, post-cardiac arrest syndrome, and acute lung injury. Accidental hypothermia is a critical illness that reduces oxygen demands, and excessive oxygen is likely to emerge. This study aimed to determine whether hyperoxia would be associated with increased mortality in patients with accidental hypothermia. METHODS: A post-hoc analysis of a nationwide multicenter prospective observational study (ICE-CRASH study) on patients with accidental hypothermia admitted in 2019-2022 was conducted. Adult patients without cardiac arrest whose core body temperature was < 32 °C and whose arterial partial pressure of oxygen (PaO2) was measured at the emergency department were included. Hyperoxia was defined as a PaO2 level of 300 mmHg or higher, and 28-day mortality was compared between patients with and without hyperoxia before rewarming. Inverse probability weighting (IPW) analyses with propensity scores were performed to adjust patient demographics, comorbidities, etiology and severity of hypothermia, hemodynamic status and laboratories on arrival, and institution characteristics. Subgroup analyses were conducted according to age, chronic cardiopulmonary diseases, hemodynamic instability, and severity of hypothermia. RESULTS: Of the 338 patients who were eligible for the study, 65 had hyperoxia before rewarming. Patients with hyperoxia had a higher 28-day mortality rate than those without (25 (39.1%) vs. 51 (19.5%); odds ratio (OR) 2.65 (95% confidence interval 1.47-4.78); p < 0.001). IPW analyses with propensity scores revealed similar results (adjusted OR 1.65 (1.14-2.38); p = 0.008). Subgroup analyses showed that hyperoxia was harmful in the elderly and those with cardiopulmonary diseases and severe hypothermia below 28 °C, whereas hyperoxia exposure had no effect on mortality in patients with hemodynamic instability on hospital arrival. CONCLUSIONS: Hyperoxia with PaO2 levels of 300 mmHg or higher before initiating rewarming was associated with increased 28-day mortality in patients with accidental hypothermia. The amount of oxygen to administer to patients with accidental hypothermia should be carefully determined. TRIAL REGISTRATION: The ICE-CRASH study was registered at the University Hospital Medical Information Network Clinical Trial Registry on April 1, 2019 (UMIN-CTR ID, UMIN000036132).


Assuntos
Hiperóxia , Hipotermia , Adulto , Humanos , Idoso , Hipotermia/complicações , Hiperóxia/complicações , Estudos Retrospectivos , Mortalidade Hospitalar , Oxigênio
13.
Cost Eff Resour Alloc ; 21(1): 43, 2023 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-37455306

RESUMO

BACKGROUND: A health-economic evaluation related to COVID-19 is urgently needed to allocate healthcare resources efficiently; however, relevant medical cost data in Japan concerning COVID-19 are scarce. METHODS: This cross-sectional study investigated the healthcare cost for hospitalized COVID-19 patients in 2021 at Keio University Hospital. We calculated the healthcare costs during hospitalization using hospital claims data and investigated the variables significantly related to the healthcare cost with multivariable analysis. RESULTS: The median healthcare cost per patient for the analyzed 330 patients was Japanese yen (JPY) 1,304,431 (US dollars ~ 11,871) (interquartile range: JPY 968,349-1,954,093), and the median length of stay was 10 days. The median healthcare cost was JPY 798,810 for mild cases; JPY 1,113,680 for moderate I cases; JPY 1,643,909 for moderate II cases; and JPY 6,210,607 for severe cases. Healthcare costs increased by 4.0% for each additional day of hospitalization; 1.26 times for moderate I cases, 1.64 times for moderate II cases, and 1.84 times for severe cases compared to mild cases; and 2.05 times for cases involving ICU stay compared to those not staying in ICU. CONCLUSIONS: We clarified the healthcare cost for hospitalized COVID-19 patients by severity in a Japanese university hospital. These costs contribute as inputs for forthcoming health economic evaluations for strategies for preventing and treating COVID-19.

14.
Prenat Diagn ; 43(3): 393-399, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36726286

RESUMO

OBJECTIVE: To identify risk factors for preterm delivery (PTD) in patients who received fetoscopic laser photocoagulation (FLP) of placental anastomoses for twin-twin transfusion syndrome (TTTS). METHODS: This retrospective cohort study prospectively analyzed and recorded perioperative data in a cohort of patients who had FLP for TTTS, identifying perioperative risk factors for PTD using a Cox proportional hazard regression model. RESULTS: Of 304 patients included, 26 (8.6%) delivered within 4 weeks of FLP. Independent predictors of delivery within 4 weeks of FLP were a history of PTD (hazard ratio [HR]: 5.91, 95% confidence interval [CI]:1.21-28.82, p = 0.03), vaginal bleeding in the second trimester (HR: 6.62, 95% CI: 1.76-24.90, p < 0.01), and amnioreduction ≥1715 mL (HR: 3.16, 95% CI: 1.11-9.05, p < 0.03). CONCLUSION: Patients with a history of PTD, preoperative vaginal bleeding, and amnioreduction ≥1715 mL were more likely to deliver prematurely.


Assuntos
Transfusão Feto-Fetal , Nascimento Prematuro , Recém-Nascido , Gravidez , Humanos , Feminino , Transfusão Feto-Fetal/cirurgia , Nascimento Prematuro/epidemiologia , Nascimento Prematuro/etiologia , Estudos Retrospectivos , Placenta , Fetoscopia/efeitos adversos , Fotocoagulação a Laser/efeitos adversos , Fatores de Risco , Idade Gestacional , Lasers , Gravidez de Gêmeos
15.
Sensors (Basel) ; 23(6)2023 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-36991603

RESUMO

The potential of ad hoc networks, which enable flexible and dynamic network establishment only by mobile terminals equipped with wireless communication devices, has recently attracted attention for the coming IoT era. Although the nature of ad hoc networks shows the advantages of their autonomous and distributed network management, a manifestation of drawbacks owing to the nature of wireless communication and the mobility of terminals are inevitable. Many routing protocols have already been proposed to address the issues by adapting to nature and achieving a certain level of improvement. However, the routing protocols still suffer from difficulties in information collection for routing and adaptive route management during communication. Moreover, there is another issue that end pair-based routing procedures prevent other end pairs from reusing the routing information effectively. To address the drawbacks of conventional routing protocols, this paper proposes VORTEX, a novel routing protocol that employs an opportunistic routing strategy using hierarchization. One of the characteristic features of VORTEX is its network-driven opportunistic forwarding, in which packets travel toward destination terminals using hierarchy as a guide without conventional route discovery procedures. Moreover, another characteristic feature of VORTEX is that the hierarchical structure also contributes to adapting to communication environment changes in an autonomous manner. In other words, VORTEX enables flexible network-wide information-based routing only with the locally collected information. The simulation results show that the proposed VORTEX could provide better service quality and reliability with improved efficiency compared to the conventional routing protocols. Furthermore, the most significant contribution is not only in the communication performance but also VORTEX omits route discovery or route maintenance from routing protocols, and formed networks themselves have a function to deliver packets toward destination terminals.

16.
J Orthop Sci ; 28(1): 255-260, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34728113

RESUMO

BACKGROUND: While various strategies of fracture fixation for trauma patients have been discussed, optimal candidates remain unclear for early definitive fixation. The aim of this study was to integrate several clinical parameters into a scoring system and determine a cut-off value for safe early definitive surgery for extremity fractures. METHODS: We retrospectively identified patients with fracture in an extremity in Japanese Trauma Data Bank from 2004 to 2019. We included adult patients who underwent open reduction and internal fixation for extremity injury before any other surgical intervention and excluded those who arrived with cardiac arrest. Several clinical parameters, such as age, vital signs, abbreviated injury scale (AIS) in the chest, and injury severity score (ISS), were examined with multivariate logistic regression models to predict in-hospital mortality, and then integrated into a scoring system based on each odds ratio. To determine a cut-off value of the scoring system for safe early definitive surgery, in-hospital mortality and/or postoperative complications were compared between patients who underwent definitive fixation within 24 h of injury and patients who did not in subgroups based on the scores. RESULTS: Of 50,631 patients eligible for this study, 16,119 (31.8%) underwent early definitive fixation. A 0-15 scoring system with parameters including age >70 years, GCS <8, systolic blood pressure <90 mmHg, AIS in the chest ≥3, ISS ≥20, and transfusion requirement within 24 h of arrival was developed. At scores ≥10, early definitive fixation was found to be significantly associated with high in-hospital mortality, and at scores <10, in-hospital mortality was comparable between the two groups. CONCLUSIONS: We integrated clinical parameters into the scoring system with a scale of 0-15 and determined that a score of 10 is the cut-off score. We determined that patients with a score <10 can safely undergo early definitive fixation.


Assuntos
Fraturas Ósseas , Adulto , Humanos , Idoso , Estudos Retrospectivos , Fraturas Ósseas/cirurgia , Fixação de Fratura , Fixação Interna de Fraturas , Escala de Gravidade do Ferimento , Extremidades
17.
Int J Mol Sci ; 24(4)2023 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-36835151

RESUMO

Chronic stress can affect gene expression in the hippocampus, which alters neural and cerebrovascular functions, thereby contributing to the development of mental disorders such as depression. Although several differentially expressed genes in the depressed brain have been reported, gene expression changes in the stressed brain remain underexplored. Therefore, this study examines hippocampal gene expression in two mouse models of depression induced by forced swim stress (FSS) and repeated social defeat stress (R-SDS). Transthyretin (Ttr) was commonly upregulated in the hippocampus of both mouse models, as determined by microarray, RT-qPCR, and Western blot analyses. Evaluation of the effects of overexpressed Ttr in the hippocampus using adeno-associated virus-mediated gene transfer revealed that TTR overexpression induced depression-like behavior and upregulation of Lcn2 and several proinflammatory genes (Icam1 and Vcam1) in the hippocampus. Upregulation of these inflammation-related genes was confirmed in the hippocampus obtained from mice vulnerable to R-SDS. These results suggest that chronic stress upregulates Ttr expression in the hippocampus and that Ttr upregulation may be involved in the induction of depression-like behavior.


Assuntos
Depressão , Hipocampo , Pré-Albumina , Animais , Camundongos , Depressão/genética , Depressão/metabolismo , Modelos Animais de Doenças , Hipocampo/metabolismo , Camundongos Endogâmicos C57BL , Pré-Albumina/genética , Pré-Albumina/metabolismo , Estresse Psicológico/metabolismo , Regulação para Cima
18.
Psychogeriatrics ; 23(6): 1036-1042, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37726104

RESUMO

BACKGROUND: It is widely known that there is low striatal 123 I-2ß-Carbomethoxy-3ß-(4-iodophenyl)-N-(3- fluoropropyl) nortropane (123 I-FP-CIT) dopamine transporter single photon emission tomography (DaT-SPECT) uptake in patients with dementia with Lewy bodies (DLB). No studies to date have analyzed the association between longitudinal changes of clinical features and DaT uptake in patients with Parkinson syndrome, particularly those with DLB. The aim of this study was to investigate the association between the longitudinal changes in DaT uptake and the severity of parkinsonism and cognitive function in DLB patients. METHODS: A total of 35 outpatients with probable DLB who underwent DaT-SPECT twice (at the initial examination and the follow-up period) in the Memory Disorder Clinic at the Department of Geriatric Medicine, Tokyo Medical University, were enrolled in this study between April 2014 and September 2020. The correlation between annual changes in DaT uptake and clinical features (cognitive function decline and parkinsonism) of the patients was analyzed. RESULTS: A significant correlation was detected between annual changes in parkinsonism symptom severity and DaT uptake in the left posterior putamen (r = -0.39, P = 0.03), and between Mini-Mental State Examination scores and DaT uptake in all regions except the right posterior putamen (P < 0.05) in patients with DLB. CONCLUSIONS: Our results suggested that the pathway from the ventrolateral tier of the substantia nigra to the putamen might be more crucial for motor function than other pathways, not only in Parkinson's disease but also in DLB.


Assuntos
Doença por Corpos de Lewy , Doença de Parkinson , Idoso , Humanos , Corpo Estriado/diagnóstico por imagem , Corpo Estriado/metabolismo , Proteínas da Membrana Plasmática de Transporte de Dopamina/metabolismo , Doença por Corpos de Lewy/diagnóstico , Doença de Parkinson/diagnóstico por imagem , Tomografia Computadorizada de Emissão de Fóton Único/métodos
19.
Biochem Biophys Res Commun ; 624: 28-34, 2022 10 08.
Artigo em Inglês | MEDLINE | ID: mdl-35932576

RESUMO

Accumulating evidence suggests that the serotonergic (5-HT) system in the amygdala has significant effects on affective states. Dysregulation of the 5-HT system in the basolateral amygdaloid complex causes affective disorders. To search for therapeutic targets, subtype specification of 5-HT receptors is crucial. The present study was undertaken to identify the 5-HT receptor subtype responsible for the 5-HT-mediated suppression of excitatory transmission to principal neurons (PNs) in the lateral amygdala (LA). Whole-cell recordings were performed to record excitatory post synaptic currents (EPSCs) in acute rat brain slices. We confirmed that 5-HT and α-m-5-HT, a broad 5-HT2 receptor agonist, attenuated EPSCs in LA PNs. The extent of suppressions by 5-HT and α-m-5-HT remained unchanged in the presence of ritanserin, a broad 5-HT2 receptor antagonist. In the presence of NAS-181, a selective 5-HT1B receptor antagonist, the extent of EPSC suppressions by 5-HT and α-m-5-HT was diminished. CP93129, a selective 5-HT1B receptor agonist, attenuated EPSCs in LA PNs, and this effect was abolished in the presence of NAS-181. Additionally, the paired-pulse ratio of EPSCs was increased by CP93129. Thus, our results indicate that 5-HT and α-m-5-HT attenuate excitatory transmissions to LA PNs via presynaptic 5-HT1B receptors.


Assuntos
Receptor 5-HT1B de Serotonina , Serotonina , Tonsila do Cerebelo , Animais , Potenciais Pós-Sinápticos Excitadores , Neurônios , Ratos , Serotonina/farmacologia , Serotonina/fisiologia , Transmissão Sináptica
20.
Am J Obstet Gynecol ; 227(6): 899.e1-899.e6, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35841937

RESUMO

BACKGROUND: Cervical polyps removed during pregnancy have been reported to be associated with preterm birth; however, the association between unremoved cervical polyps and preterm birth has not been elucidated. OBJECTIVE: This study aimed to clarify the relationship between cervical polyps detected before 12 weeks of gestation managed expectantly and spontaneous preterm birth. STUDY DESIGN: This retrospective cohort study included pregnant women who visited a tertiary perinatal center before 12 weeks of gestation between January 2015 and December 2019. The exclusion criteria were as follows: multiple gestations, loss or termination of pregnancy before 12 weeks of gestation, major fetal anomalies, fetal chromosomal abnormalities, fetal demise, having undergone removal of cervical polyps before the first visit to our hospital, and moving to other hospitals before delivery. A vaginal speculum examination was routinely performed during a prenatal visit before 12 weeks of gestation. When a cervical polyp was detected on speculum examination, it was managed expectantly, unless gynecologic malignancy was suspected. Relationships between cervical polyps and spontaneous preterm birth before 34 weeks of gestation were evaluated using logistic regression analysis and Cox proportional-hazards analysis adjusted for known confounders for spontaneous preterm birth. RESULTS: A total of 4172 pregnant women were included, of whom 92 (2.2%) had a cervical polyp detected before 12 weeks of gestation. None of the women underwent polypectomy during pregnancy. The incidence of spontaneous preterm birth before 34 weeks of gestation was higher in pregnant women with cervical polyps than in those without them (5.4% vs 0.7%; P<.01). Logistic regression analysis revealed that cervical polyps were an independent risk factor for spontaneous preterm birth before 34 weeks of gestation (adjusted odds ratio, 4.09; 95% confidence interval, 1.70-9.81; P<.01). The adjusted hazard ratio for spontaneous preterm birth before 34 weeks of gestation among women with vs without cervical polyps was 2.95 (95% confidence interval, 1.32-6.62; P<.01). CONCLUSION: Cervical polyps detected before 12 weeks of gestation managed expectantly are a significant risk factor for spontaneous preterm birth before 34 weeks of gestation.


Assuntos
Pólipos , Nascimento Prematuro , Neoplasias do Colo do Útero , Feminino , Recém-Nascido , Gravidez , Humanos , Nascimento Prematuro/epidemiologia , Nascimento Prematuro/etiologia , Colo do Útero/patologia , Estudos Retrospectivos , Segundo Trimestre da Gravidez , Cuidado Pré-Natal , Pólipos/cirurgia , Pólipos/patologia , Neoplasias do Colo do Útero/patologia
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