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1.
N Engl J Med ; 391(6): 526-537, 2024 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-39115062

RESUMO

BACKGROUND: In early-onset severe hemolytic disease of the fetus and newborn (HDFN), transplacental transfer of maternal antierythrocyte IgG alloantibodies causes fetal anemia that leads to the use of high-risk intrauterine transfusions in order to avoid fetal hydrops and fetal death. Nipocalimab, an anti-neonatal Fc receptor blocker, inhibits transplacental IgG transfer and lowers maternal IgG levels. METHODS: In an international, open-label, single-group, phase 2 study, we assessed treatment with intravenous nipocalimab (30 or 45 mg per kilogram of body weight per week) administered from 14 to 35 weeks' gestation in participants with pregnancies at high risk for recurrent early-onset severe HDFN. The primary end point was live birth at 32 weeks' gestation or later without intrauterine transfusions as assessed against a historical benchmark (0%; clinically meaningful difference, 10%). RESULTS: Live birth at 32 weeks' gestation or later without intrauterine transfusions occurred in 7 of 13 pregnancies (54%; 95% confidence interval, 25 to 81) in the study. No cases of fetal hydrops occurred, and 6 participants (46%) did not receive any antenatal or neonatal transfusions. Six fetuses received an intrauterine transfusion: five fetuses at 24 weeks' gestation or later and one fetus before fetal loss at 22 weeks and 5 days' gestation. Live birth occurred in 12 pregnancies. The median gestational age at delivery was 36 weeks and 4 days. Of the 12 live-born infants, 1 received one exchange transfusion and one simple transfusion and 5 received only simple transfusions. Treatment-related decreases in the alloantibody titer and IgG level were observed in maternal samples and cord blood. No unusual maternal or pediatric infections were observed. Serious adverse events were consistent with HDFN, pregnancy, or prematurity. CONCLUSIONS: Nipocalimab treatment delayed or prevented fetal anemia or intrauterine transfusions, as compared with the historical benchmark, in pregnancies at high risk for early-onset severe HDFN. (Funded by Janssen Research and Development; UNITY ClinicalTrials.gov number, NCT03842189.).


Assuntos
Anticorpos Monoclonais Humanizados , Transfusão de Sangue Intrauterina , Eritroblastose Fetal , Imunoglobulina G , Humanos , Feminino , Gravidez , Recém-Nascido , Anticorpos Monoclonais Humanizados/uso terapêutico , Anticorpos Monoclonais Humanizados/efeitos adversos , Adulto , Imunoglobulina G/sangue , Transfusão de Sangue Intrauterina/efeitos adversos , Nascido Vivo , Isoanticorpos/sangue , Receptores Fc , Idade Gestacional , Antígenos de Histocompatibilidade Classe I
3.
Am J Perinatol ; 2024 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-39197469

RESUMO

OBJECTIVE: Nipocalimab is a neonatal Fc receptor (FcRn)-blocking monoclonal antibody that inhibits placental immunoglobulin G (IgG) transfer and lowers circulating maternal IgG levels. In an open-label, single-arm, phase 2 study, nipocalimab demonstrated evidence of safety and efficacy that support further investigation in a pivotal phase 3 trial of recurrent hemolytic disease of the fetus and newborn (HDFN). The phase 3 AZALEA study aims to evaluate the efficacy and safety of nipocalimab in a larger population at risk for severe HDFN, defined as HDFN associated with poor fetal outcomes or neonatal death. STUDY DESIGN: AZALEA is a multicenter, randomized, placebo-controlled, double-blind, phase 3 study enrolling alloimmunized pregnant individuals (N≈120) at risk for severe HDFN based on obstetric history. Participants are randomized 2:1 to receive intravenous 45 mg/kg nipocalimab or placebo weekly from 13-16 to 35 weeks gestational age (GA). During the double-blind treatment period, participants receive standard-of-care weekly monitoring for fetal anemia until planned delivery at 37 to 38 weeks GA. Postnatal follow up periods are 24 weeks for maternal participants and 104 weeks for neonates/infants. RESULTS: The primary endpoint is the proportion of pregnancies that do not result in IUT, hydrops fetalis, or fetal loss/neonatal death from all causes. Key secondary endpoints include the severity of HDFN as measured by a composite HDFN severity index, the earliest time to occurrence of IUT or hydrops fetalis, the modified neonatal mortality and morbidity index in liveborn neonates, and the number of IUTs received. Other endpoints are safety, patient- and caregiver-reported outcomes, pharmacokinetics, pharmacodynamics (eg, IgG, FcRn receptor occupancy), and immunogenicity of nipocalimab. CONCLUSION: AZALEA, the first placebo-controlled, randomized, multicenter, prospective trial in severe HDFN, is designed to evaluate the safety and efficacy of nipocalimab, a potential preventive and noninvasive intervention, in at-risk HDFN pregnancies.

4.
Br J Nutr ; : 1-8, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38826083

RESUMO

Many improvements have been made to bring infant formula (IF) closer to human milk (HM) regarding its nutritional and biological properties. Nevertheless, the protein components of HM and IF are still different, which may affect their digestibility. This study aimed to evaluate and compare the protein digestibility of HM and IF using the infant INFOGEST digestion method. Pooled HM and a commercial IF were subjected to the infant INFOGEST method, which simulates the physiological digestion conditions of infants, with multiple directions, i.e. the curd state, gel images of SDS-PAGE, molecular weight distribution, free amino acid concentrations and in vitro protein digestion rate. HM underwent proteolysis before digestion and tended to have a higher protein digestion rate with finer curds during gastric digestion, than the IF. However, multifaceted analyses showed that the protein digestibility of HM and IF was not significantly different after gastrointestinal digestion. In conclusion, the infant INFOGEST method showed that the digestibility of HM and IF proteins differed to some extent before digestion and after gastric digestion, but not at the end of gastrointestinal digestion. The findings of this study will contribute to the refinement of IF with better protein digestibility in infant stomach.

5.
Clin Pharmacol Ther ; 115(6): 1251-1257, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38506485

RESUMO

Recent reports related to in utero exposure of marketed immunosuppressive biologics led to clinical recommendations to delay live vaccinations for infants due to the concern of reduced vaccine effectiveness and/or increased risk of vaccine-related disease. These delays can increase the risk of children contracting vaccine preventable diseases, yet the alternative cessation of biologics during pregnancy may result in increased autoimmune disease activity for the pregnant person, raising complex benefit-risk (B-R) considerations and trade-offs. Our goal is to develop a conceptual framework for B-R assessment based on the key benefits and risks pregnant people would consider for themselves and their children when continuing (vs. discontinuing) a biologic during pregnancy. The proposed framework defines the decision contexts, key domains and attributes for potential benefits, and risks of biologic use during pregnancy, informed by a literature review of indications for biologics and refined with key clinical stakeholders. The framework includes both the pregnant person taking the biologic and the infant potentially exposed to the biologic in utero, with potential benefit and risk domains and attributes for each participant. To advance this conceptual framework, there are considerations of potential biases and uncertainty of available data that will be imperative to address when quantifying the B-R framework. For these reasons, we recommend the formation of a consortium to ensure development of a robust, validated framework that can be adopted in the healthcare setting.


Assuntos
Produtos Biológicos , Humanos , Gravidez , Feminino , Produtos Biológicos/efeitos adversos , Produtos Biológicos/uso terapêutico , Medição de Risco , Imunossupressores/efeitos adversos , Imunossupressores/uso terapêutico , Vacinação/efeitos adversos , Efeitos Tardios da Exposição Pré-Natal/prevenção & controle
7.
Nutrients ; 15(3)2023 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-36771361

RESUMO

Maternal diet may affect human milk macronutrients, but it remains to be elucidated whether this is also influential in infant growth. This study aimed to examine (1) how maternal diet influences human milk macronutrients, and (2) to what extent the variation in milk macronutrients affects infant growth during the first month of life. In 71 Japanese lactating women, maternal dietary information was collected from the brief-type self-administered diet history questionnaire, and anthropometry of mother-infant dyads was collected from medical records. Macronutrients in milk were analyzed by a Human Milk Analyzer. Maternal retinol intake was associated with the carbohydrate content in human milk at 1-month postpartum (standardized ß coefficient: 0.287; p = 0.038). Moreover, the energy content in human milk was associated with an increase in the weight standard deviation score based on the WHO growth standard at 1 month of age (standardized ß coefficient: 0.399; p = 0.046). Nevertheless, the milk macronutrient was not associated with the risk of infant growth abnormalities. In conclusion, a part of the maternal diet impacts macronutrient contents in human milk, but milk macronutrients have a limited effect on infant growth only within the normal growth curve during the first month of life.


Assuntos
Lactação , Leite Humano , Humanos , Lactente , Feminino , Japão , Aleitamento Materno , Dieta
8.
J Agric Food Chem ; 71(5): 2503-2513, 2023 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-36695832

RESUMO

The INFOGEST method is a valuable tool for understanding and monitoring food digestion as an alternative to in vivo assays. However, few studies have compared animal and alternative protein sources in terms of protein quality using the INFOGEST method. This study aimed to evaluate the protein quality of milk-, plant-, and insect-based protein materials by in vitro protein digestibility and in vitro digestible indispensable amino acid score (DIAAS), following the INFOGEST method. Milk-based protein materials had the highest protein digestibility (86.1-90.8%), followed by soy (85.1%) and wheat (82.3%). These materials had significantly higher protein digestibility compared with zein (65.1%), cricket (63.6%), and mealworm (69.5%). Additionally, the mean values of in vitro DIAAS of milk-based protein materials (105.0-137.5) were higher than those of plant- and insect-based protein materials (1.9-91.0). Milk-based protein materials have higher protein quality than plant- and insect-based protein materials by the nutritional evaluation following the INFOGEST digestion method.


Assuntos
Íleo , Leite , Animais , Leite/metabolismo , Íleo/metabolismo , Digestão , Proteínas/metabolismo , Aminoácidos/metabolismo , Proteínas do Leite/metabolismo , Insetos/metabolismo
10.
Nutrients ; 13(6)2021 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-34067270

RESUMO

BACKGROUND: Plasma albumin (ALB) reflects protein nutritional status in rats, but it is not clear whether it is associated with dietary protein insufficiency in pregnant women and/or their risk of low birth weight delivery. This study aimed to investigate whether maternal serum ALB redox state reflects maternal protein nutritional status and/or is associated with infant birth weights. METHODS: The relationship between the serum reduced ALB ratio and infant birth weight was examined in an observational study of 229 Japanese pregnant women. A rat model simulating fetal growth restriction, induced by protein-energy restriction, was used to elucidate the relationship between maternal nutritional status, maternal serum ALB redox state, and birth weight of the offspring. RESULTS: In the human study, serum reduced ALB ratio in the third trimester was significantly and positively correlated with infant birth weight. In the rat study, serum reduced ALB ratio and birth weight in the litter decreased as the degree of protein-energy restriction intensified, and a significant and positive correlation was observed between them in late pregnancy. CONCLUSIONS: Maternal serum reduced ALB ratio in the third trimester is positively associated with infant birth weight in Japanese pregnant women, which would be mediated by maternal protein nutritional status.


Assuntos
Peso ao Nascer , Fenômenos Fisiológicos da Nutrição Materna , Estado Nutricional , Albumina Sérica/análise , Adulto , Animais , Proteínas Alimentares/administração & dosagem , Feminino , Retardo do Crescimento Fetal/epidemiologia , Humanos , Recém-Nascido de Baixo Peso , Recém-Nascido , Japão , Oxirredução , Gravidez , Terceiro Trimestre da Gravidez/sangue , Gestantes , Ratos , Ratos Wistar
11.
Front Nutr ; 8: 813690, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35071301

RESUMO

Background: The gut microbiome and fecal metabolites of breastfed infants changes during lactation, and are influenced by breast milk components. This study aimed to investigate dynamic associations of milk components with the infant gut microbiome and fecal metabolites throughout the lactation period in a mother-infant model. Methods: One month after delivery, breast milk and subsequent infant feces were collected in a pair for 5 months from a mother and an exclusively breastfed infant. Composition of the fecal microbiome was determined with 16S rRNA sequencing. Low-molecular-weight metabolites, including human milk oligosaccharides (HMOs), and antibacterial proteins were measured in feces and milk using 1H NMR metabolomics and enzyme-linked immunosorbent assays. The association of milk bioactive components with the infant gut microbiome and fecal metabolites was determined with Python clustering and correlation analyses. Results: The HMOs in milk did not fluctuate throughout the lactation period. However, they began to disappear in infant feces at the beginning of month 4. Notably, at this time-point, a bifidobacterium species switching (from B. breve to B. longum subsp. infantis) occurred, accompanied by fluctuations in several metabolites including acetate and butyrate in infant feces. Conclusions: Milk bioactive components, such as HMOs, might play different roles in the exclusively breastfed infants depending on the lactation period.

12.
Am J Perinatol ; 38(S 01): e309-e317, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-32380566

RESUMO

OBJECTIVE: The aim of this study is to assess the efficacy and safety of retosiban in spontaneous preterm labor (sPTL). STUDY DESIGN: Two multicenter, randomized, and double-blind trials compared retosiban with placebo and retosiban with atosiban in women with a singleton pregnancy and intact membranes in sPTL at 24 to 336/7 weeks' gestation. Coprimary endpoints in the placebo-controlled trial were time to delivery (TTD) or treatment failure (whichever occurred first) and neonatal composite morbidity and mortality. The primary endpoint of the atosiban comparator trial was TTD. RESULTS: The trials were terminated early because of slow recruitment. The placebo-controlled trial enrolled 23 participants (February 2016-July 2017; 2.6% of target);the atosiban-comparator trial enrolled 97 (March 2015-August 2017; 29% of target). Baseline participant characteristics were similar between treatments. In the placebo-controlled trial, mean gestational ages at randomization were 30.8 (retosiban, n = 10) and 30.5 weeks (placebo, n = 13), and mean times to delivery/treatment failure were 18.9 days (retosiban) and 11.1 days (placebo). Two and four neonates in the retosiban and placebo groups, respectively, had ≥1 component of the neonatal composite endpoint. In the atosiban-comparator trial, mean gestational age at randomization was 31.5 weeks (for both retosiban, n = 47, and atosiban, n = 50), and adjusted mean TTDs were 32.51 days (retosiban) and 33.71 days (atosiban; p > 0.05). Adverse events were no more common with retosiban than placebo or atosiban. CONCLUSION: Despite considerable efforts to conduct two adequate and well-controlled studies in patients with sPTL, both studies were unable to recruit effectively and consequently terminated prematurely. Key factors negatively affecting participation were patient and physician resistance to use of a placebo comparator, lack of investigator consensus on diagnostic criteria and acceptance of protocol procedures, and ethics committee decisions. Meaningful cooperation between pharmaceutical companies, regulatory authorities, and the obstetric community is essential for future development of drugs to treat sPTL.


Assuntos
Trabalho de Parto Prematuro/tratamento farmacológico , Piperazinas/uso terapêutico , Tocolíticos/uso terapêutico , Vasotocina/análogos & derivados , Adolescente , Adulto , Método Duplo-Cego , Feminino , Idade Gestacional , Humanos , Recém-Nascido , Piperazinas/efeitos adversos , Gravidez , Fatores de Tempo , Contração Uterina/efeitos dos fármacos , Vasotocina/efeitos adversos , Vasotocina/uso terapêutico , Adulto Jovem
13.
Br J Nutr ; 125(6): 633-643, 2021 03 28.
Artigo em Inglês | MEDLINE | ID: mdl-32814607

RESUMO

Protein undernutrition contributes to the development of various diseases in broad generations. Urinary metabolites may serve as non-invasive biomarkers of protein undernutrition; however, this requires further investigation. We aimed to identify novel urinary metabolites as biomarker candidates responsive to protein undernutrition. Adult rats were fed control (CT; 14 % casein) or isoenergetic low-protein (LP; 5 % casein) diets for 4 weeks. 1H NMR metabolomics was applied to urine, plasma and liver samples to identify metabolites responsive to protein undernutrition. Liver samples were subjected to mRNA microarray and quantitative PCR analyses to elucidate the mechanisms causing fluctuations in identified metabolites. Urinary taurine levels were significantly lower in the LP group than in the CT group at week 1 and remained constant until week 4. Hepatic taurine level and gene expression level of cysteine dioxygenase type 1 were also significantly lower in the LP group than in the CT group. Urinary trimethylamine N-oxide (TMAO) levels were significantly higher in the LP group than in the CT group at week 2 and remained constant until week 4. Hepatic TMAO level and gene expression levels of flavin-containing mono-oxygenase 1 and 5 were also significantly higher in the LP group than in the CT group. In conclusion, urinary taurine and TMAO levels substantially responded to protein undernutrition. Furthermore, changes in hepatic levels of these metabolites and gene expressions associated with their metabolic pathways were also reflected in their fluctuating urinary levels. Thus, taurine and TMAO could act as non-invasive urinary biomarker candidates to detect protein undernutrition.


Assuntos
Metilaminas/urina , Deficiência de Proteína/urina , Taurina/urina , Animais , Biomarcadores/urina , Cisteína Dioxigenase/genética , Cisteína Dioxigenase/metabolismo , Dieta com Restrição de Proteínas , Perfilação da Expressão Gênica , Ontologia Genética , Fígado/metabolismo , Espectroscopia de Ressonância Magnética , Masculino , Metaboloma , Deficiência de Proteína/sangue , Deficiência de Proteína/diagnóstico , Deficiência de Proteína/metabolismo , Ratos , Ratos Wistar , Transcriptoma
14.
Metabolomics ; 16(4): 48, 2020 04 10.
Artigo em Inglês | MEDLINE | ID: mdl-32274593

RESUMO

INTRODUCTION: Crohn's disease (CD) is a chronic, relapsing inflammatory bowel disease affecting the gastrointestinal tract. Although its precise etiology has not been fully elucidated, an imbalance of the intestinal microbiota has been known to play a role in CD. Fecal metabolites derived from microbiota may be related to the onset and progression of CD OBJECTIVES: This study aimed to clarify the transition of gut microbiota and fecal metabolites associated with disease progression using SAMP1/YitFc mice, a model of spontaneous CD METHODS: The ileum tissues isolated from SAMP1/YitFc mice at different ages were stained with hematoxylin-eosin for histologic characterization with CD progression. Feces from control, Institute of Cancer Research (ICR; n = 6), and SAMP1/YitFc (n = 8) mice at different ages were subjected to microbial analysis and 1H nuclear magnetic resonance (NMR) analysis to investigate fluctuations in gut microbiota and fecal metabolites with CD progression RESULTS: Relative abundance of the Lachnospiraceae, Ruminococcaceae, Bacteroidaceae, and Bacteroidales S24-7 at family-level gut microbiota and fecal metabolites, such as short-chain fatty acids, lactate, glucose, xylose, and choline, dramatically fluctuated with histologic progression of intestinal inflammation in SAMP1/YitFc mice. Unlike the other metabolites, fecal taurine concentration in SAMP1/YitFc mice was higher than ICR mice regardless of age CONCLUSION: The fecal metabolites showing characteristic fluctuations may help to understand the inflammatory mechanism associated with CD, and might be utilized as potential biomarkers in predicting CD pathology.


Assuntos
Doença de Crohn/metabolismo , Modelos Animais de Doenças , Fezes/microbiologia , Metabolômica , Animais , Doença de Crohn/patologia , Camundongos , Camundongos Endogâmicos ICR , Camundongos Mutantes
15.
Front Nutr ; 6: 12, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30828577

RESUMO

We recently reported that plasma albumin redox state, which correlates with albumin synthesis rate, could be associated with the quality of dietary protein. Aiming to elucidate the association between them, plasma albumin redox state was investigated in rats fed various kinds of AIN-93G-based low protein diets. Plasma albumin redox state was shifted to a more oxidized state in rats fed 3% casein (CN) diet than those fed 3% whey protein or 3% wheat gluten diet, while supplementing 3% CN diet with cystine reversed it to a more reduced state, indicating that cystine would complement the shortage of cysteine in CN, thereby increasing albumin synthesis rate. Supplementation with glutathione, a cysteine-containing antioxidative tripeptide, normalized hepatic glutathione redox state modulated by ingestion of 3% CN diet, but it only reversed the oxidized shift of plasma albumin redox state to an extent similar to cystine alone or the constituting amino acid mixture of glutathione (i.e., glutamic acid, cystine, and glycine), indicating that glutathione would primarily serve as a source of cysteine rather than exert its antioxidative activity. Plasma albumin would thus be influenced by amino acid balance in dietary proteins, and it could be useful as a biomarker that contributes to prevention of protein under-nutriton, caused by not only insufficient protein intake but also ingestion of poor-quality protein.

16.
Food Chem ; 277: 423-431, 2019 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-30502166

RESUMO

Physicochemical properties of casein (CN) materials manufactured using different processes are well studied; however, data on their bioaccessibility or bioactivity are limited. We compared the digestion patterns and glucagon-like peptide-1 (GLP-1)-releasing activities of micellar CN concentrate (MCC) and sodium caseinate (SCN). MCC and SCN mixed with whey protein isolate (SCN + WPI) were subjected to in vitro gastrointestinal digestion; the digestibility of MCC was higher than that of SCN + WPI, and both CN materials showed different patterns of peptides released after in vitro digestion. A comparison of GLP-1-releasing activities showed that MCC induced GLP-1 secretion to a greater extent than SCN + WPI. Candidate peptides identified from CN digesta were chemically synthesized to test their GLP-1-releasing activity. GPVRGPFPIIV identified only in the MCC digesta, could stimulate GLP-1 release. In conclusion, the digestion patterns and GLP-1-releasing activity of CN materials depend on the production process.


Assuntos
Caseínas/química , Células Enteroendócrinas/metabolismo , Trato Gastrointestinal/metabolismo , Peptídeo 1 Semelhante ao Glucagon/metabolismo , Modelos Biológicos , Animais , Linhagem Celular , Fenômenos Químicos , Cromatografia Líquida , Digestão , Camundongos , Peso Molecular , Tamanho da Partícula , Extração em Fase Sólida , Espectrometria de Massas em Tandem
17.
Front Nutr ; 5: 64, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30090810

RESUMO

The redox state of plasma albumin shifts in response to dietary protein intake in growing rats, and the shift is more sensitive than that of plasma albumin level, a classical marker of protein nutritional status. While it has been suggested that plasma albumin redox state could be useful as a novel marker of protein nutritional status, the above animal model is highly sensitive to dietary protein intake and the observation may not be extrapolated widely to humans. This study aimed to investigate whether albumin redox state also reflects protein nutritional status in adult rats, which have a lower dietary protein requirement and are less responsive to protein intake. Male adult rats were placed on AIN-93M diet (14% casein), or AIN-93M-based low protein diets (10 or 5% casein) ad libitum for 24 weeks. Whereas there was no significant difference in body weight between the groups at the end of the experimental period, the 5% casein diet group had the smallest gastrocnemius muscle weight among the groups, which was significantly lower than that of the 10% casein diet group. Plasma albumin level was also lower in the 5% casein diet group compared with the other groups, but the differences were limited and inconsistent during the experimental period. Among the albumin redox isoforms such as mercaptalbumin, non-mercaptalbumin-1, and non-mercaptalbumin-2, the ratio of non-mercaptalbumin-1 among total albumin was significantly higher in the 5% casein diet group, and the increase remained constant throughout the experimental period. Increased non-mercaptalbumin-1 ratio would thus demonstrate the presence of potential protein undernutrition in adult rats, as manifested only by a decreased gain in a specific type of skeletal muscle; non-mercaptalbumin-1 among total albumin ratio could be useful as a robust marker of protein nutritional status, contributing to prevention of protein undernutrition-related diseases such as frailty and sarcopenia.

19.
Artigo em Inglês | MEDLINE | ID: mdl-25570563

RESUMO

Novel diagnostic method named "sonocytometry", in which streaming blood cell is diagnosed by the reflection of high frequency ultrasound from the cell, is proposed. In the present study, the differentiation of the particle size is performed as a basic study on sonocytometry. Ultrasonic backscatter signal from either 80 or 100 µm diameter polystyrene particles was measured by an ultrasonic transducer with the central frequency of 30 MHz. The spectrum of the reflected signal showed different characteristics according to the particle diameter. Theoretical value of backscatter was calculated by Faran-Hickling model and the correlation coefficient of measured and theoretical value by varying the spherical diameter showed the local maximum value at either 80 or 100 µm diameter. The principle was also validated on the streaming particles in a flow channel. The method successfully classified the particle size. Sonocytometry would be clinically applied for diagnosis of malaria or leukemia.


Assuntos
Células Sanguíneas/citologia , Poliestirenos/química , Separação Celular , Humanos , Modelos Biológicos , Tamanho da Partícula , Imagens de Fantasmas , Ultrassonografia
20.
Eur J Neurosci ; 31(8): 1359-67, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20384770

RESUMO

We previously demonstrated that N-methyl-D-aspartate (NMDA) treatment (50 microM, 3 h) induced astrocytic production of monocyte chemoattractant protein-1 (MCP-1, CCL2), a CC chemokine implicated in ischemic and excitotoxic brain injury, in rat corticostriatal slice cultures. In this study, we investigated the signaling mechanisms for NMDA-induced MCP-1 production in slice cultures. The results showed a close correlation between NMDA-induced neuronal injury and MCP-1 production, and an abrogation of NMDA-induced MCP-1 production in NMDA-pretreated slices where neuronal cells had been eliminated. These results collectively indicate that NMDA-induced neuronal injury led to astrocytic MCP-1 production. NMDA-induced MCP-1 production was significantly inhibited by U0126, an inhibitor of extracellular signal-regulated kinase (ERK). Immunostaining for phosphorylated ERK revealed that transient neuronal ERK activation was initially induced and subsided within 30 min, followed by sustained ERK activation in astrocytes. Treatment with U0126 during only the early phase (U0126 was washed out at 15 or 30 min after NMDA administration) suppressed early activation of ERK in neuronal cells, but not later activation of ERK in astrocytes. In this case, MCP-1 production was not suppressed, suggesting that activation of neuronal ERK is not necessary for MCP-1 production. In contrast, delayed application of U0126 at 3 h after the beginning of NMDA treatment inhibited MCP-1 production to the same degree as that observed when U0126 was applied from 3 h before NMDA administration. These findings suggest that sustained activation of the ERK signaling pathway in astrocytes plays a key role in neuronal injury-induced MCP-1 production.


Assuntos
Astrócitos/metabolismo , Lesões Encefálicas/metabolismo , Quimiocina CCL2/metabolismo , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Sistema de Sinalização das MAP Quinases/fisiologia , Neurônios/metabolismo , Animais , Astrócitos/efeitos dos fármacos , Astrócitos/enzimologia , Lesões Encefálicas/tratamento farmacológico , Lesões Encefálicas/enzimologia , Butadienos/farmacologia , Córtex Cerebral/efeitos dos fármacos , Córtex Cerebral/enzimologia , Córtex Cerebral/metabolismo , Corpo Estriado/efeitos dos fármacos , Corpo Estriado/enzimologia , Corpo Estriado/metabolismo , Inibidores Enzimáticos/farmacologia , MAP Quinases Reguladas por Sinal Extracelular/antagonistas & inibidores , Técnicas In Vitro , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , N-Metilaspartato/metabolismo , Neurônios/efeitos dos fármacos , Neurônios/enzimologia , Nitrilas/farmacologia , Fosforilação , Ratos , Ratos Wistar , Fatores de Tempo
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