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1.
Artigo em Inglês | MEDLINE | ID: mdl-39008535

RESUMO

Blinatumomab is a CD3/CD19-directed bispecific T-cell engager used to treat relapsed or refractory B-cell precursor acute lymphoblastic leukemia (BCP-ALL). Although blinatumomab has shown efficacy, it can cause serious adverse events, including cytokine release syndrome and neurological events. Among the neurological events, encephalopathy is rare, and knowledge is lacking. Herein, we present a pediatric case of blinatumomab-associated encephalopathy that initially presented with refractory convulsions and later developed into a cerebral infarction. The patient experienced prolonged paralysis and increased brain damage.

2.
Bioengineering (Basel) ; 11(6)2024 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-38927780

RESUMO

This study aimed to evaluate walking independence in acute-care hospital patients using neural networks based on acceleration and angular velocity from two walking tests. Forty patients underwent the 10-m walk test and the Timed Up-and-Go test at normal speed, with or without a cane. Physiotherapists divided the patients into two groups: 24 patients who were monitored or independent while walking with a cane or without aids in the ward, and 16 patients who were not. To classify these groups, the Transformer model analyzes the left gait cycle data from eight inertial sensors. The accuracy using all the sensor data was 0.836. When sensor data from the right ankle, right wrist, and left wrist were excluded, the accuracy decreased the most. When analyzing the data from these three sensors alone, the accuracy was 0.795. Further reducing the number of sensors to only the right ankle and wrist resulted in an accuracy of 0.736. This study demonstrates the potential of a neural network-based analysis of inertial sensor data for clinically assessing a patient's level of walking independence.

3.
Geriatr Gerontol Int ; 2024 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-38943538

RESUMO

AIM: To identify factors associated with locomotive syndrome (LS) using medical questionnaire data and machine learning. METHODS: A total of 1575 participants underwent the LS risk tests from the third survey of the research on osteoarthritis/osteoporosis against disability study (ROAD) study. LS was defined as stage 1 or higher based on clinical decision limits of the Japanese Orthopaedic Association. A total of 1335 items of medical questionnaire data came from this study. The number of medical questionnaire items was reduced from 1335 to 331 in data cleaning. From the 331 items, identify factors associated with LS use by light gradient boosting machine-based recursive feature elimination with cross-validation. The performance of each set was evaluated using an average of seven performance metrics, including 95% confidence intervals, using a bootstrapping method. The smallest set of items is determined with the highest average of receiver operating characteristic area under the curve (ROC-AUC) under 20 items as association factors of LS. Additionally, the performance of the selected items was compared with the LS risk tests and Loco-check. RESULTS: The nine items have the best average ROC-AUC under 20 items. The nine items show an average ROC-AUC of 0.858 (95% confidence interval 0.816-0.898). Age and back pain during walking were strongly associated with the prevalence of LS. The ROC-AUC of nine items is higher than that of existing questionnaire-based LS assessments, including the 25-question Geriatric Locomotor Scale and Loco-check. CONCLUSIONS: The identified nine items could aid early LS detection, enhancing understanding and prevention. Geriatr Gerontol Int 2024; ••: ••-••.

5.
Osteoarthr Cartil Open ; 6(2): 100454, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38469555

RESUMO

Objective: Considering the joint space width and osteophyte area (OPA) of the knee joints of Japanese adults, this study elucidated the ten-year trends in medial minimum joint space width (mJSW) and OPA using data of two independent cohorts from a population-based cohort study. Methods: The baseline survey of the Research on Osteoarthritis/Osteoporosis Against Disability study was conducted from 2005 to 2007; 2975 participants (1041 men, 1934 women) completed all knee osteoarthritis (OA) examinations. The fourth survey was performed from 2015 to 2016; distinct 2445 participants (764 men, 1681 women) completed identical examinations. The medial mJSW and medial tibial OPA were measured bilaterally using an automated system. Results: The mean medial mJSW (standard deviation) was 3.22 (0.96) mm and 2.65 (0.95) mm at baseline and 3.81 (1.20) mm and 3.13 (1.15) mm in the fourth survey for men and women, respectively. The mean medial mJSW in the fourth survey was significantly greater in both men and women in all age groups than at baseline (p â€‹< â€‹0.01). The mean OPAs in men aged 40-49 and 60-69 years and women aged 40-49, 50-59, 60-69, and 70-79 years were significantly smaller in the fourth survey (p â€‹< â€‹0.05). The trend in mJSW remained the same even after adjusting for confounding factors in the multivariate analysis, but the trend in OPA was weakened. Conclusions: A significant improvement in the medial mJSW within 10 years could decrease the incidence and progression of knee OA and prevent the risk of walking disability.

6.
J Chemother ; : 1-11, 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38451087

RESUMO

Factors involved in the susceptibility of third-generation cephalosporins (3GCs) to bacteremia caused by Citrobacter freundii complex, Enterobacter cloacae complex, and Klebsiella aerogenes were investigated based on a case-case-control design. Antimicrobial therapy administered 30 days prior to bacteremia and hospitalization within 90 days were common risk factors for the 3GC susceptible and 3GC non-susceptible groups, while hospitalization from an institution or another hospital was a specific risk factor for the 3GC non-susceptible group. We also attempted to examine the factors affecting the clinical outcome of bacteremia. Hospitalization more than 14 days before the onset of bacteremia was an independent factor indicating poor clinical outcome. In contrast, the implementation of source control was an independent predictor of successful treatment. Although a longer hospital stay before the onset of bacteremia was associated with worse clinical outcomes, implementation of source control may have contributed to improved treatment outcomes for bacteremia.

7.
Hematol Rep ; 16(1): 98-105, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38534880

RESUMO

Severe congenital neutropenia (SCN) is characterized by chronic neutropenia with recurrent infections from early infancy and a predisposition to myelodysplastic syndrome/acute myeloid leukemia (AML). Allogeneic hematopoietic stem cell transplantation (HSCT) is the only curative treatment for patients with SCN who develop myelodysplastic syndrome/AML. We report an 8-year-old girl with SCN carrying an ELANE mutation that had been refractory to granulocyte colony-stimulating factor. The patient experienced recurrent infections and then developed AML. The counts of leukemic blasts that harbored both CSF3R and RUNX1 mutations spontaneously decreased with antimicrobial therapy, leading to partial remission. After AML recurrence, HSCT was successfully performed using modified chemotherapy and a conditioning regimen. Serial donor lymphocyte infusions against mixed chimerism induced complete donor chimerism over 4 years without any infections or AML relapse. This case suggests the importance of carefully managing neutropenia-related infections, leukemia progression, and HSCT in patients with SCN developing AML.

8.
Sci Rep ; 14(1): 4363, 2024 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-38388829

RESUMO

The purpose of this study was to compare the acceleration and surface electromyography (EMG) of the lower extremity and trunk muscles during straight-leg raising (SLR) in patients with incomplete cervical cord injury according to their levels of walking independence. Twenty-four patients were measured acceleration and EMG during SLR held for 10 s. Data were analyzed separately for the dominant and nondominant sides and compared between the nonindependent (NI) and independent (ID) groups based on their levels of walking independence. Frequency analysis of the EMG showed that the high-frequency (HF) band of the contralateral biceps femoris (BF) in the ID group and bands below the medium-frequency (MF) of the BF and the HF and MF bands of the rectus abdominis in the NI group were significantly higher during dominant and nondominant SLR. During the nondominant SLR, the low-frequency band of the internal oblique and the MF band of the external oblique were significantly higher in the NI group. The ID group mobilized muscle fiber type 2 of the BF, whereas the NI group mobilized type 1 of the BF and types 2 and 1 of the trunk muscles to stabilize the pelvis. This result was more pronounced during the nondominant SLR.


Assuntos
Medula Cervical , Traumatismos da Medula Espinal , Humanos , Perna (Membro)/fisiologia , Músculo Esquelético/fisiologia , Caminhada/fisiologia , Extremidade Inferior , Eletromiografia , Reto do Abdome
9.
Sci Rep ; 14(1): 1585, 2024 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-38238438

RESUMO

Femoroacetabular impingement has increasingly been recognized as a cause of primary hip osteoarthritis; however, its epidemiological indications remain unclear. We aimed to clarify the epidemiological indications and factors associated with cam deformity in a large-scale population-based cohort in Japan. Overall, 1480 participants (2960 hips) (491 men, 989 women; mean age, 65.3 years) analyzed in the third survey of the Research on Osteoarthritis/Osteoporosis Against Disability study were included. The α angle and spinopelvic parameters (lumbar lordosis, sacral slope, pelvic tilt, and pelvic incidence) were radiographically measured. Cam deformity was defined as α angle ≥ 60°. Overall, the cam deformity prevalence was 147/2960 (5.0%). Cam deformity prevalence tended to increase with age; in the univariate analysis, a higher percentage of men was observed in the group with cam deformity than in the group without it. No relationship was observed between cam deformity and hip pain. Factors associated with α angle were examined via multiple regression analysis for each gender; α angle was significantly associated with age and BMI in each gender. The α angle and PT were correlated in women. Thus, α angle and cam deformity prevalence increase with age in Japanese individuals. Accordingly, cam deformity can be considered a developmental disease.


Assuntos
Impacto Femoroacetabular , Articulação do Quadril , Masculino , Humanos , Feminino , Idoso , Japão/epidemiologia , Impacto Femoroacetabular/diagnóstico por imagem , Impacto Femoroacetabular/epidemiologia , Impacto Femoroacetabular/etiologia , Quadril , Pelve
10.
J Adolesc Young Adult Oncol ; 13(1): 197-202, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37535825

RESUMO

Purpose: Although fertility preservation for pediatric cancer patients is becoming more widespread in Japan, some facilities do not provide sufficient information regarding fertility. This study aimed to elucidate the problems pertaining to the lack of information about fertility among patients. Methods: Based on a 2020 survey, seminars addressing fertility preservation were held from the Designated Pediatric Cancer Care Hospitals in each of the seven blocks in Japan to their partner hospital (pediatric cancer hospitals). The seminar consisted of lectures and group discussions, and a questionnaire was also administered after each seminar. Results: In the group discussions, a lack of explanations to patients and explanatory materials for children were cited as issues by many facilities. The survey results revealed a lack of material explaining fertility preservation and a lack of knowledge among health care providers. There were also many requests to use the patient explanation videos presented at the seminar. Conclusion: The results indicate that further education for health care providers by seminar and other sources and enhancement of explanatory materials are important for fertility preservation in pediatric cancer hospitals in Japan.


Assuntos
Preservação da Fertilidade , Neoplasias , Humanos , Criança , Preservação da Fertilidade/métodos , Japão , Neoplasias/terapia , Fertilidade , Serviços de Saúde , Inquéritos e Questionários
11.
Tohoku J Exp Med ; 262(1): 5-12, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-37853608

RESUMO

The global coronavirus disease 2019 (COVID-19) pandemic has necessitated the establishment of new medical care systems worldwide. Medical staff treating COVID-19 patients perform their care duties in highly challenging and psychologically demanding situations, raising concerns about their impact on patient safety. Therefore, this study aimed to investigate and characterize incident reports related to COVID-19 patients to clarify the impact of COVID-19 on patient safety. The study included data from 557 patients admitted to the Critical Care Center of a tertiary-care teaching hospital in Osaka, Japan, from April 2020 to March 2021. The patients were divided into two groups: COVID-19 (n = 106) and non-COVID-19 (n = 451) and compared based on various characteristics, incident reporting rates, and the content of incident reports. The findings indicated a significantly higher rate of patients with incident reports in the COVID-19 group compared to the non-COVID-19 group (49.1% vs. 24.4%, P < 0.001). In addition, quantitative text analysis revealed that the topic ratio, consisting of "respiration," "circuit," "settings," "connection," "nursing," "ventilator," "control," "tape," "Oxylog®," and "artificial nose" was significantly higher in the incident reports of the COVID-19 group (P = 0.003). In conclusion, COVID-19 patients are more susceptible to adverse incidents and may face a higher risk of patient safety issues. The characteristic topics in incident reports involving COVID-19 patients primarily revolved around ventilator-related issues. In the future, the methodology used in the current study may be utilized to identify incident characteristics and implement appropriate countermeasures in the event of unknown patient safety issues.


Assuntos
COVID-19 , Humanos , Japão/epidemiologia , COVID-19/epidemiologia , Gestão de Riscos , Cuidados Críticos , Hospitais de Ensino
12.
Int J Hematol ; 118(5): 627-635, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37735323

RESUMO

Primary autoimmune neutropenia in young children is characterized by chronic neutropenia and positivity for antibodies against human neutrophil antigens (HNAs). This study analyzed the clinical characteristics of 402 children with neutropenia to identify differences between those with and without HNA-1 antibodies (HNA1abs). HNAabs in sera were detected by granulocyte immunofluorescence testing using flow cytometry. Relative fluorescence intensity (RFI) values were used to divide patients into positive (PG, n = 302), borderline (BG, n = 34), and negative (NG, n = 66) groups. The antibodies reacted to HNA-1a alone (59%), HNA-1b alone (1%), and HNA-1a/1b (40%). The PG had a significantly lower absolute neutrophil count before definitive diagnosis and a 1.6- to 2-times greater risk of hospitalization during neutropenia than the other groups. The median duration of neutropenia was longest in the PG at 25 months, followed by 20 months in the BG and 14 months in the NG. This large-scale cohort characterizes clinically distinct groups using the RFI value for HNA1abs in young children with neutropenia. Detection of HNA1abs may aid in understanding the clinical characteristics of children with neutropenia.


Assuntos
Neutropenia , Neutrófilos , Humanos , Criança , Pré-Escolar , Relevância Clínica , Neutropenia/diagnóstico , Autoanticorpos , Granulócitos , Isoantígenos
13.
Haemophilia ; 29(5): 1359-1365, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37639381

RESUMO

INTRODUCTION: Joint health is one of the most important factors contributing to a healthy life in patients with haemophilia. Recent study revealed that starting early prophylaxis was not enough to prevent joint disease in most paediatric patients with haemophilia. AIM: In this study, we aimed to determine the age-specific incidence of acute joint disease during childhood at single haemophilia treatment centre (HTC). METHOD: The joint health in 48 patients was evaluated based on consecutive US testing for 5 years at annual multidisciplinary comprehensive care. RESULTS: During the study period, 23 patients (47.9%) had no joint disease since the initial examination, whereas 13 patients (27.0%) showed development from negative to positive findings. The incidence of joint disease increased with age: 0% in preschool, 5.3% in elementary school, 14.3% in junior high school and 35% beyond high school age. Among the 13 patients who developed joint disease, two experienced acquired synovitis that resolved during the follow-up period. Statistical analysis revealed that the patients who routinely underwent follow-up by the HTC exhibited a significantly lower incidence of joint disease than did those followed up at other institutions (p < .001). CONCLUSION: These results indicated that close check-up, including routine joint examination using US as well as frequent assessment of pharmacokinetic profile at the HTC, might play an important role in avoiding joint disease among paediatric patients with haemophilia.


Assuntos
Hemofilia A , Artropatias , Sinovite , Humanos , Criança , Pré-Escolar , Hemofilia A/complicações , Hemofilia A/epidemiologia , Incidência , Artropatias/complicações , Artropatias/epidemiologia , Fatores Etários
14.
Mol Clin Oncol ; 19(1): 53, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37323249

RESUMO

Few large population-based studies have examined the prevalence of atrophic gastritis (AG) and Helicobacter pylori infection in Japan. The purpose of the present study was to estimate the prevalence of AG and H. pylori infection by age, in addition to investigating their change rates from 2005 to 2016 in Japan using data from a large population-based cohort. A total of 3,596 participants [1,690 in the baseline survey (2005-2006) and 1,906 at the fourth survey (2015-2016)] aged 18 to 97 years were included in the cohort. The prevalence of AG and H. pylori infection were examined at baseline and in the fourth survey based on serological tests for the H. pylori antibody titer and pepsinogen levels. The prevalence of AG and H. pylori infection were 40.1% (men, 44.1%; women, 38.0%) and 52.2% (men, 54.8%; women, 50.8%), respectively, at baseline. AG seropositivity rates showed a significant decrease from 40.1 to 25.8% in 10 years. H. pylori seropositivity rates decreased significantly from 52.2 to 35.5% in 10 years. Stratified for age, the prevalence of AG showed an increasing trend with age, whereas the prevalence of H. pylori infection increased with aging, except for in the elderly group, showing an inverted U-shaped association. In this population-based, cross-sectional study with a 10-year interval survey, the prevalence of AG and H. pylori infection decreased significantly. This change may influence the prevalence of H. pylori-related diseases, including extra-gastric disorders associated with H. pylori-induced systemic subclinical inflammation and hypochlorhydria, such as colorectal neoplasia and arteriosclerosis.

15.
Int J Hematol ; 118(3): 364-373, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37358749

RESUMO

Hematopoietic stem cell transplantation (HSCT) is only indicated for acute lymphoblastic leukemia (ALL) patients for whom other treatments are unlikely to be curative. However, outcomes of patients not in complete remission (CR) at HSCT remain very poor. To improve the outcomes of patients receiving HSCT, it is important to obtain detailed clinical information about patients with ALL receiving HSCT in CR and not in CR. Patients enrolled in the Japan Association of Childhood Leukemia Study ALL-02 who underwent HSCT and were not in CR (non-CR patients, n = 55) were examined. The 1-year overall survival (OS) rate of non-CR patients was 27.3%. Compared with CR patients, non-CR patients experienced very early and early relapse significantly more frequently and had poorer prognostic factors. Most interestingly, high hyperdiploid (HHD) patients showed an excellent 1-year OS of 80%. In addition, long-term survival among surviving HHD patients was longer than 5 years. All eight patients who survived after undergoing HSCT while not in CR were younger than 10 years at initial diagnosis and were negative for central nervous system involvement. While limited, these results suggest that a subset of patients may benefit from HSCT while not in CR.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Leucemia-Linfoma Linfoblástico de Células Precursoras , Humanos , Criança , Transplante de Células-Tronco Hematopoéticas/métodos , Indução de Remissão , Intervalo Livre de Doença , Transplante Homólogo , Leucemia-Linfoma Linfoblástico de Células Precursoras/terapia , Aneuploidia , Estudos Retrospectivos
16.
Children (Basel) ; 10(5)2023 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-37238419

RESUMO

Neuroblastoma (NB) is a neural crest-derived malignant tumor which is diagnosed during infancy in approximately 40% of cases; spontaneous regressions are observed, but there are varying degrees of severity. Treatment is indicated if an infant's condition is at risk of deterioration. Herein, we report the case of a 42-day-old boy who presented with hepatomegaly and was diagnosed with stage MS NB. A pathological diagnosis of "poorly differentiated neuroblastoma with low mitosis-karyorrhexis index, favorable histology" was made; his tumor cells were hyperdiploid and MYCN was not amplified. Because he had respiratory distress caused by the rapidly evolving hepatomegaly, two cycles of chemotherapy containing vincristine and cyclophosphamide were administered in the second and fourth weeks of admission; however, his abdominal tumor did not shrink. In the sixth week of admission, chemotherapy was revised to pirarubicin and cyclophosphamide, and the tumor began to shrink. After discharge, there was no re-elevation of tumor markers; after 1 year, the hepatomegaly and liver metastases disappeared. During the 5-year follow-up, his growth and development were normal and he progressed without sequelae. A regimen that includes pirarubicin could merit further study in the treatment of early infants with stage MS low-risk NB who are at risk of complications.

17.
PNAS Nexus ; 2(4): pgad104, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37077884

RESUMO

Advances in next-generation sequencing technology have identified many genes responsible for inborn errors of immunity (IEI). However, there is still room for improvement in the efficiency of genetic diagnosis. Recently, RNA sequencing and proteomics using peripheral blood mononuclear cells (PBMCs) have gained attention, but only some studies have integrated these analyses in IEI. Moreover, previous proteomic studies for PBMCs have achieved limited coverage (approximately 3000 proteins). More comprehensive data are needed to gain valuable insights into the molecular mechanisms underlying IEI. Here, we propose a state-of-the-art method for diagnosing IEI using PBMCs proteomics integrated with targeted RNA sequencing (T-RNA-seq), providing unique insights into the pathogenesis of IEI. This study analyzed 70 IEI patients whose genetic etiology had not been identified by genetic analysis. In-depth proteomics identified 6498 proteins, which covered 63% of 527 genes identified in T-RNA-seq, allowing us to examine the molecular cause of IEI and immune cell defects. This integrated analysis identified the disease-causing genes in four cases undiagnosed in previous genetic studies. Three of them could be diagnosed by T-RNA-seq, while the other could only be diagnosed by proteomics. Moreover, this integrated analysis showed high protein-mRNA correlations in B- and T-cell-specific genes, and their expression profiles identified patients with immune cell dysfunction. These results indicate that integrated analysis improves the efficiency of genetic diagnosis and provides a deep understanding of the immune cell dysfunction underlying the etiology of IEI. Our novel approach demonstrates the complementary role of proteogenomic analysis in the genetic diagnosis and characterization of IEI.

18.
Sci Rep ; 13(1): 4900, 2023 03 25.
Artigo em Inglês | MEDLINE | ID: mdl-36966180

RESUMO

The molecular pathophysiology underlying lumbar spondylosis development remains unclear. To identify genetic factors associated with lumbar spondylosis, we conducted a genome-wide association study using 83 severe lumbar spondylosis cases and 182 healthy controls and identified 65 candidate disease-associated single nucleotide polymorphisms (SNPs). Replication analysis in 510 case and 911 control subjects from five independent Japanese cohorts identified rs2054564, located in intron 7 of ADAMTS17, as a disease-associated SNP with a genome-wide significance threshold (P = 1.17 × 10-11, odds ratio = 1.92). This association was significant even after adjustment of age, sex, and body mass index (P = 7.52 × 10-11). A replication study in a Korean cohort, including 123 case and 319 control subjects, also verified the significant association of this SNP with severe lumbar spondylosis. Immunohistochemistry revealed that fibrillin-1 (FBN1) and ADAMTS17 were co-expressed in the annulus fibrosus of intervertebral discs (IVDs). ADAMTS17 overexpression in MG63 cells promoted extracellular microfibrils biogenesis, suggesting the potential role of ADAMTS17 in IVD function through interaction with fibrillin fibers. Finally, we provided evidence of FBN1 involvement in IVD function by showing that lumbar IVDs in patients with Marfan syndrome, caused by heterozygous FBN1 gene mutation, were significantly more degenerated. We identified a common SNP variant, located in ADAMTS17, associated with susceptibility to lumbar spondylosis and demonstrated the potential role of the ADAMTS17-fibrillin network in IVDs in lumbar spondylosis development.


Assuntos
Disco Intervertebral , Osteoartrite da Coluna Vertebral , Espondilose , Humanos , Fibrilina-1 , Fibrilinas/análise , Estudo de Associação Genômica Ampla , Disco Intervertebral/química , Microfibrilas , Espondilose/genética
20.
J Cereb Blood Flow Metab ; 43(1): 138-152, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36138557

RESUMO

Cerebral hemodynamics fluctuates spontaneously over broad frequency ranges. However, its spatiotemporal coherence of flow oscillations in cerebral microcirculation remains incompletely understood. The objective of this study was to characterize the spatiotemporal fluctuations of red blood cells (RBCs) and plasma flow in the rat cerebral microcirculation by simultaneously imaging their dynamic behaviors. Comparisons of changes in cross-section diameters between RBC and plasma flow showed dissociations in penetrating arterioles. The results indicate that vasomotion has the least effect on the lateral movement of circulating RBCs, resulting in variable changes in plasma layer thickness. Parenchymal capillaries exhibited slow fluctuations in RBC velocity (0.1 to 0.3 Hz), regardless of capillary diameter fluctuations (<0.1 Hz). Temporal fluctuations and the velocity of RBCs decreased significantly at divergent capillary bifurcations. The results indicate that a transit of RBCs generates flow resistance in the capillaries and that slow velocity fluctuations of the RBCs are subject to a number of bifurcations. In conclusion, the high-frequency oscillation of the blood flow is filtered at the bifurcation through the capillary networks. Therefore, a number of bifurcations in the cerebral microcirculation may contribute to the power of low-frequency oscillations.


Assuntos
Células Sanguíneas , Plasma , Ratos , Animais , Análise Espaço-Temporal
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