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1.
Int J Hyperthermia ; 41(1): 2349080, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38705588

RESUMO

OBJECTIVES: To investigate image-guided volumetric hyperthermia strategies using the ExAblate Body MR-guided focused ultrasound ablation system, involving mechanical transducer movement and sector-vortex beamforming. MATERIALS AND METHODS: Acoustic and thermal simulations were performed to investigate volumetric hyperthermia using mechanical transducer movement combined with sector-vortex beamforming, specifically for the ExAblate Body transducer. The system control in the ExAblate Body system was modified to achieve fast transducer movement and MR thermometry-based hyperthermia control, mechanical transducer movements and electronic sector-vortex beamforming were combined to optimize hyperthermia delivery. The experimental validation was performed using a tissue-mimicking phantom. RESULTS: The developed simulation framework allowed for a parametric study with varying numbers of heating spots, sonication durations, and transducer movement times to evaluate the hyperthermia characteristics for mechanical transducer movement and sector-vortex beamforming. Hyperthermic patterns involving 2-4 sequential focal spots were analyzed. To demonstrate the feasibility of volumetric hyperthermia in the system, a tissue-mimicking phantom was sonicated with two distinct spots through mechanical transducer movement and sector-vortex beamforming. During hyperthermia, the average values of Tmax, T10, Tavg, T90, and Tmin over 200 s were measured within a circular ROI with a diameter of 10 pixels. These values were found to be 8.6, 7.9, 6.6, 5.2, and 4.5 °C, respectively, compared to the baseline temperature. CONCLUSIONS: This study demonstrated the volumetric hyperthermia capabilities of the ExAblate Body system. The simulation framework developed in this study allowed for the evaluation of hyperthermia characteristics that could be implemented with the ExAblate MRgFUS system.


Assuntos
Hipertermia Induzida , Imageamento por Ressonância Magnética , Humanos , Hipertermia Induzida/métodos , Imageamento por Ressonância Magnética/métodos , Ablação por Ultrassom Focalizado de Alta Intensidade/métodos , Imagens de Fantasmas
2.
Gene ; 910: 148337, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38432533

RESUMO

Bronchopulmonary dysplasia (BPD) is a serious chronic lung disease affecting extremely preterm infants. While mitochondrial dysfunction has been investigated in various medical conditions, limited research has explored mitochondrial DNA (mtDNA) gene mutations, specifically in BPD. This study aimed to evaluate mitochondrial mtDNA gene mutations in extremely preterm infants with BPD. In this prospective observational study, we enrolled a cohort of extremely preterm infants diagnosed with BPD. Clinical data were collected to provide comprehensive patient profiles. Peripheral blood mononuclear cells were isolated from whole-blood samples obtained within a defined timeframe. Subsequently, mtDNA extraction and sequencing using next-generation sequencing technology were performed to identify mtDNA gene mutations. Among the cohort of ten extremely preterm infants with BPD, mtDNA sequencing revealed the presence of mutations in seven patients, resulting in a total of twenty-one point mutations. Notably, many of these mutations were identified in loci associated with critical components of the respiratory chain complexes, vital for proper mitochondrial function and cellular energy production. This pilot study provides evidence of mtDNA point mutations in a subset of extremely preterm infants with BPD. These findings suggest a potential association between mitochondrial dysfunction and the pathogenesis of BPD. Further extensive investigations are warranted to unravel the mechanisms underlying mtDNA mutations in BPD.


Assuntos
Displasia Broncopulmonar , Doenças Mitocondriais , Lactente , Humanos , Recém-Nascido , Lactente Extremamente Prematuro , Displasia Broncopulmonar/genética , Leucócitos Mononucleares , Projetos Piloto , Mutação , DNA Mitocondrial/genética
3.
Eur Radiol ; 34(2): 1137-1145, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37615768

RESUMO

OBJECTIVE: To assess the safety and efficacy of magnetic resonance-guided focused ultrasound (MRgFUS) for the treatment extra-abdominal desmoids. METHODS: A total of 105 patients with desmoid fibromatosis (79 females, 26 males; 35 ± 14 years) were treated with MRgFUS between 2011 and 2021 in three centers. Total and viable tumors were evaluated per patient at last follow-up after treatment. Response and progression-free survival (PFS) were assessed with (modified) response evaluation criteria in solid tumors (RECIST v.1.1 and mRECIST). Change in Numerical Rating Scale (NRS) pain and 36-item Short Form Health Survey (SF-36) scores were compared. Treatment-related adverse events were recorded. RESULTS: The median initial tumor volume was 114 mL (IQR 314 mL). After MRgFUS, median total and viable tumor volume decreased to 51 mL (95% CI: 30-71 mL, n = 101, p < 0.0001) and 29 mL (95% CI: 17-57 mL, n = 88, p < 0.0001), respectively, at last follow-up (median: 15 months, 95% CI: 11-20 months). Based on total tumor measurements (RECIST), 86% (95% CI: 75-93%) had at least stable disease or better at last follow-up, but 50% (95% CI: 38-62%) of remaining viable nodules (mRECIST) progressed within the tumor. Median PFS was reached at 17 and 13 months for total and viable tumors, respectively. NRS decreased from 6 (IQR 3) to 3 (IQR 4) (p < 0.001). SF-36 scores improved (physical health (41 (IQR 15) to 46 (IQR 12); p = 0.05, and mental health (49 (IQR 17) to 53 (IQR 9); p = 0.02)). Complications occurred in 36%, most commonly 1st/2nd degree skin burns. CONCLUSION: MRgFUS reduced tumor volume, reduced pain, and improved quality of life in this series of 105 patients with extra-abdominal desmoid fibromatosis. CLINICAL RELEVANCE STATEMENT: Imaging-guided ablation is being increasingly used as an alternative to surgery, radiation, and medical therapy for the treatment of desmoid fibromatosis. MR-guided high-intensity focused ultrasound is an incisionless ablation technique that can be used to reduce tumor burden effectively and safely. KEY POINTS: • Desmoid fibromatosis was treated with MR-guided high-intensity focused ultrasound in 105 patients. • MR-guided focused ultrasound ablation reduced tumor volume and pain and improved quality of life. • MR-guided focused ultrasound is a treatment option for patients with extra-abdominal desmoid tumors.


Assuntos
Fibromatose Agressiva , Ablação por Ultrassom Focalizado de Alta Intensidade , Humanos , Masculino , Feminino , Fibromatose Agressiva/diagnóstico por imagem , Fibromatose Agressiva/terapia , Fibromatose Agressiva/patologia , Estudos Retrospectivos , Qualidade de Vida , Ablação por Ultrassom Focalizado de Alta Intensidade/métodos , Dor , Resultado do Tratamento
4.
Quant Imaging Med Surg ; 13(12): 7987-7995, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38106288

RESUMO

Background: T2-weighted Single Shot Fast Spin Echo (SSFSE) scans at 3 Tesla (3T) are increasingly used to image fetal pathology due to their excellent tissue contrast resolution and signal-to-noise ratio (SNR). Temperature changes that may occur in response to radio frequency (RF) pulses used for these sequences at 3T have not been studied in human fetal brains. To evaluate the safety of T2-weighted SSFSE for fetal brains at 3T, magnetic resonance (MR) thermometry was used to measure relative temperature changes in a typical clinical fetal brain MR exam. Methods: Relative temperature was estimated using sets of gradient recalled echo (GRE) images acquired before and after T2-weighted SSFSE images which lasted 27.47±8.19 minutes. Thirty-one fetuses with cardiac abnormalities, and 20 healthy controls were included in this study. Fetal brain temperature was estimated by proton resonance frequency (PRF) thermometry and compared to the estimated temperature in the gluteal muscle of the mother. Seven scans with excessive motion were excluded. Local outlier factor (LOF) was performed to remove 12 additional scans with spurious phase measurements due to motion degradation and potential field drift. Linear regression was performed to determine if temperature changes are dependent on the rate of energy deposition during the scan. Results: For the 32 participants used in the analysis, 17 with cardiac abnormalities and 15 healthy controls, the average relative fetal temperate change was 0.19±0.73 ℃ higher than the mother, with no correlation between relative temperature change and the rate of images acquired during the scans (regression coefficient =-0.05, R-squared =0.05, P=0.22, F-statistic =1.60). The difference in the relative temperature changes between the fetal brain and mother's gluteal tissue in the healthy controls was on average 0.08 ℃ lower and found not to be statistically different (P=0.76) to the group with cardiac abnormalities. Conclusions: Our results indicate that the estimated relative temperature changes of the fetal brain compared to the mother's gluteal tissue from RF pulses during the course of the T2-weighted SSFSE fetal MR exam are minimal. The differences in acquired phase between these regions through the exam were found not to be statistically different. These findings support that fetal brain imaging at 3T is within FDA limits and safe.

5.
Int J Hyperthermia ; 40(1): 2151649, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36535967

RESUMO

PURPOSE: To develop an effective and practical reconstruction pipeline to achieve motion-robust, multi-slice, real-time MR thermometry for monitoring thermal therapy in abdominal organs. METHODS: The application includes a fast spiral magnetic resonance imaging (MRI) pulse sequence and a real-time reconstruction pipeline based on multi-baseline proton resonance frequency shift (PRFS) method with visualization of temperature imaging. The pipeline supports multi-slice acquisition with minimal reconstruction lag. Simulations with a virtual motion phantom were performed to investigate the influence of the number of baselines and respiratory rate on the accuracy of temperature measurement. Phantom experiments with ultrasound heating were performed using a custom-made motion phantom to evaluate the performance of the pipeline. Lastly, experiments in healthy volunteers (N = 2) without heating were performed to evaluate the accuracy and stability of MR thermometry in abdominal organs (liver and kidney). RESULTS: The multi-baseline approach with greater than 25 baselines resulted in minimal temperature errors in the simulation. Phantom experiments demonstrated a 713 ms update time for 3-slice acquisitions. Temperature maps with 30 baselines showed clear temperature distributions caused by ultrasound heating in the respiratory phantom. Finally, the pipeline was evaluated with physiologic motions in healthy volunteers without heating, which demonstrated the accuracy (root mean square error [RMSE]) of 1.23 ± 0.18 °C (liver) and 1.21 ± 0.17 °C (kidney) and precision of 1.13 ± 0.11 °C (liver) and 1.16 ± 0.15 °C (kidney) using 32 baselines. CONCLUSIONS: The proposed real-time acquisition and reconstruction pipeline allows motion-robust, multi-slice, real-time temperature monitoring within the abdomen during free breathing.


Assuntos
Termometria , Humanos , Termometria/métodos , Temperatura , Imageamento por Ressonância Magnética/métodos , Temperatura Corporal , Fígado/cirurgia , Imagens de Fantasmas
6.
Int J Hyperthermia ; 38(1): 1590-1600, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34749579

RESUMO

PURPOSE: The ExAblate body MRgFUS system requires advanced beamforming strategies for volumetric hyperthermia. This study aims to develop and evaluate electronic beam steering, multi-focal patterns, and sector vortex beamforming approaches in conjunction with partial array activation using an acoustic and biothermal simulation framework along with phantom experiments. METHODS: The simulation framework was developed to calculate the 3D acoustic intensity and temperature distribution resulting from various beamforming and scanning strategies. A treatment cell electronically sweeping a single focus was implemented and evaluated in phantom experiments. The acoustic and thermal focal size of vortex beam propagation was quantified according to the vortex modes, number of active array elements, and focal depth. RESULTS: Turning off a percentage of the outer array to increase the f-number increased the focal size with a decrease in focal gain. 60% active elements allowed generating a sonication cell with an off-axis of 10 mm. The vortex mode number 4 with 60% active elements resulted in a larger heating volume than using the full array. Volumetric hyperthermia in the phantom was evaluated with the vortex mode 4 and respectively performed with 100% and 80% active elements. MR thermometry demonstrated that the volumes were found to be 18.8 and 29.7 cm3, respectively, with 80% array activation producing 1.58 times larger volume than the full array. CONCLUSIONS: This study demonstrated that both electronic beam steering and sector vortex beamforming approaches in conjunction with partial array activation could generate large volume heating for HT delivery using the ExAblate body array.


Assuntos
Ablação por Ultrassom Focalizado de Alta Intensidade , Termometria , Imageamento por Ressonância Magnética , Imagens de Fantasmas , Sonicação
7.
BMC Pediatr ; 21(1): 120, 2021 03 11.
Artigo em Inglês | MEDLINE | ID: mdl-33706730

RESUMO

BACKGROUND: To evaluate the long-term functional and structural pulmonary development in children with repaired congenital diaphragmatic hernia (CDH) and to identify the associated perinatal-neonatal risk factors. METHODS: Children with repaired CDH through corrective surgery who were born at gestational age ≥ 35 weeks were included in this analysis. Those who were followed for at least 5 years were subjected to spirometry and chest computed tomography for evaluation of their functional and structural growth. Main bronchus diameters and lung volumes (total, left/right) were measured. According to total lung volume (TLV) relative to body surface area, children were grouped into TLV ≥ 50 group and TLV < 50 group and the associations with perinatal-neonatal factors were analyzed. RESULTS: Of the 28 children (mean age, 6.2 ± 0.2 years) with left-sided CDH, 7 (25%) had abnormal pulmonary function, of whom 6 (87%) showed restrictive patterns. All pulmonary functions except FEF25-75% were worse than those in matched healthy control group. Worse pulmonary function was significantly associated with small head and abdominal circumferences at birth. The mean TLV was 1339.1 ± 363.9 mL and LLV/TLV was 47.9 ± 2.5 mL. Children with abnormal pulmonary function were more likely to have smaller lung volumes. In multivariate analysis, abdominal circumference at birth was significantly associated with abnormal lung volume. CONCLUSIONS: A quarter of children with repaired CDH showed abnormal pulmonary function. Small abdominal circumference at birth was associated with abnormal pulmonary function and lower TLV. .


Assuntos
Hérnias Diafragmáticas Congênitas , Criança , Feminino , Idade Gestacional , Hérnias Diafragmáticas Congênitas/diagnóstico por imagem , Hérnias Diafragmáticas Congênitas/cirurgia , Humanos , Lactente , Recém-Nascido , Pulmão/diagnóstico por imagem , Medidas de Volume Pulmonar , Gravidez
8.
Transl Pediatr ; 10(11): 3091-3095, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34976775

RESUMO

In this study, we present the case of a 900 g, male infant born at 27+5 weeks, who was placed on high frequency oscillatory ventilation (HFOV) until repair of a left congenital diaphragmatic hernia (CDH) at 39 days of life (DOL). To date, this is the smallest infant with repair of the left CDH reported in the literature. After birth, he passed the cardiopulmonary stabilization phase and successfully underwent delayed surgery; in the process, he received ventilator assistance through HFOV. He weighed 1,660 gm at the time of surgery. We performed the thoracoscopic primary closure of the diaphragmatic defect. He was extubated on post-operation day (POD) 7 and discharged from hospital on POD 36 with 0.1 L/min supplemental oxygen via nasal cannula. He is being followed for growth and development and there has been no recurrence at the surgical site at 24 months of corrected age. In this case, high mean airway pressure (MAP) was required based on the patient's weight to achieve adequate recruitment of the left lung, and the patient was diagnosed with mental developmental delay on Bayley Scales of Infant Development-II. Thus, we suggest that the postnatal course and long-term outcomes for extremely low birth weight (ELBW) and preterm infants with left CDH is different from that for full-term babies. Therefore, future research should focus on preterm infants with left CDH.

9.
Obstet Gynecol Sci ; 61(3): 417-420, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29780786

RESUMO

The ex utero intrapartum treatment (EXIT) procedure was introduced to reduce fetal hypoxic damage while establishing an airway in fetuses with upper and lower airway obstruction. Delivery of the fetal head and shoulders while maintaining the uteroplacental circulation offers time to secure the fetal airway. Here, we report two cases of EXIT procedure for fetal airway obstruction, which were successfully managed with extensive preoperative planning by a professional multidisciplinary team.

10.
Clin Chim Acta ; 482: 199-202, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29654786

RESUMO

Nonimmune hydrops fetalis is the most severe clinical manifestation of lysosomal storage diseases (LSDs). Around 14 different LSDs have been accounted for as 1-15% of the cause of nonimmune hydrops fetalis. We report a Korean infant affected by an extremely rare but severe form of sialic acid storage disease. The patient presented with nonimmune hydrops fetalis, dysmorphic facial features, hepatosplenomegaly, and dysostosis multiplex and died at 39 days of age due to persistent pulmonary hypertension. LSD was suspected based on the presence of diffuse vacuolation of syncytiotrophoblast, villous stromal cells, and intermediate trophoblast in placental biopsy. Increased excretion of urinary free sialic acid was detected by liquid chromatography-tandem mass spectrometry. The patient was compound heterozygous of the c.908G>A (p.Trp303Ter) and the splicing mutation c.1259+5G>T (IVS9+5 G>T) in the SLC17A5 gene.


Assuntos
Hidropisia Fetal , Doenças por Armazenamento dos Lisossomos/complicações , Doença do Armazenamento de Ácido Siálico/patologia , Processamento Alternativo/genética , Humanos , Hipertensão Pulmonar/mortalidade , Lactente , Recém-Nascido , Doenças por Armazenamento dos Lisossomos/patologia , Mutação , Transportadores de Ânions Orgânicos/genética , Polimorfismo de Nucleotídeo Único , República da Coreia , Doença do Armazenamento de Ácido Siálico/genética , Simportadores/genética
11.
Korean J Pediatr ; 61(1): 30-34, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29441110

RESUMO

Congenital pulmonary airway malformation (CPAM), previously known as congenital cystic adenomatoid malformation, is a rare developmental lung abnormality associated with rhabdomyosarcoma, pleuropulmonary blastoma, and mucinous adenocarcinoma of the lung. We report an unusual case of a 10-day-old male newborn with a left lower lobe pulmonary cyst who underwent lobectomy, which revealed type II CPAM complicated by multifocal mucinous adenocarcinoma. KRAS sequencing revealed a somatic mutation in Codon12 (GGT → GAT), suggesting the development of a mucinous adenocarcinoma in the background of mucinous metaplasia. Mucinous adenocarcinoma is the most common lung tumor associated with CPAM, but it generally occurs in older children and adults. Further, all cases in the literature are of type I CPAM. This case in a neonate indicates that malignant transformation can occur very early in type II CPAM.

12.
Obstet Gynecol Sci ; 61(1): 161-164, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29372164

RESUMO

Coronary arteriovenous fistula (CAVF) is a rare condition defined as an anomalous termination of the coronary arteries. The etiology of CAVF is either congenital or acquired, and iatrogenic CAVF is most commonly caused by cardiovascular surgery or percutaneous intervention. Most of the prenatally diagnosed CAVFs were related to complex heart disease, and only few cases of an isolated CAVF have been reported to date. We successfully diagnosed an isolated CAVF by fetal echocardiography at 25.3 weeks of gestation. Accurate prenatal diagnosis resulted in the prompt decision for postnatal surgical correction, and the neonate thrived well without any complications.

13.
Polymers (Basel) ; 10(4)2018 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-30966385

RESUMO

Highly active catalyst systems for polymerizing 2,6-dimethylphenol were studied by using aromatic amine ligands and copper(I) chloride. The aromatic amine ligands employed were pyridine, 1-methylimidazole, 2-aminopyridine, 3-aminopyridine, and 4-aminopyridine. A mixture of chloroform and methanol (9:1, v/v) was used as a polymerization solvent. All experiments were performed with oxygen uptake measurement apparatus, while the reaction rate for each aromatic amine ligand-Cu catalyst system and the amount of by-product, 3,3',5,5'-Tetramethyl-4,4'diphenoquinone (DPQ), were measured to determine the efficiency of the catalyst systems. The 4-aminopyridine/Cu (I) catalyst system was found to be extremely efficient in poly(2,6-dimethyl-1,4-phenylene ether) (PPE) synthesis; it had the fastest reaction rate of 6.98 × 10-4 mol/L·s and the lowest DPQ production. The relatively high basicity of 4-aminopyridne and the less steric hindrance arising from a coordination of Cu and 4-aminopyridine in this catalyst are responsible for the fast polymerization rate. When 2-aminoprydine (an isomer of 4-aminopyridine) was used as a ligand, however, no polymerization occurred probably due to steric hindrance.

14.
Pediatr Pulmonol ; 52(12): 1572-1577, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29028157

RESUMO

BACKGROUND: Surgical resection of large symptomatic congenital pulmonary airway malformation (CPAM) in newborns has high risks of mortality and postoperative morbidity. This study aimed to report the clinical outcomes of newborns who underwent percutaneous transthoracic catheter drainage (PTCD) of large symptomatic CPAM before surgical resection. METHODS: This was a retrospective, descriptive study based on review of the medical records of newborn infants who required surgical resection of large symptomatic CPAM at a single tertiary hospital from 2001 to 2017. The clinical outcomes were compared between patients who underwent surgical resection following PTCD (PTCD group) and those who underwent surgical resection alone (non-PTCD group). RESULTS: A total of 17 newborns were included. PTCD was performed in seven cases; the median age at the time of the initial PTCD was 4 days (range, 0-20 days). Following PTCD in all cases, chest radiograph demonstrated a dramatic reduction in the sizes of the cysts and improvement of mediastinal shift and the Alveolar-arterial oxygen difference decreased. The median duration between initial PTCD and surgery was 4 days (range, 2-33 days). PTCD-related complications included pneumothorax (n = 2), catheter displacement (n = 1), and failure to drain (n = 1). Compared with the non-PTCD group (6 of 10), the PTCD group had a tendency toward lower rates of postoperative complications (1 of 7). CONCLUSION: PTCD can be an effective interim management for symptomatic newborn infants who require emergency surgical resection of large CPAM.


Assuntos
Cateterismo/métodos , Drenagem/métodos , Cuidados Pré-Operatórios , Anormalidades do Sistema Respiratório/terapia , Cateterismo/efeitos adversos , Catéteres , Drenagem/efeitos adversos , Humanos , Lactente , Recém-Nascido , Pulmão/anormalidades , Pulmão/cirurgia , Pneumotórax/etiologia , Complicações Pós-Operatórias , Anormalidades do Sistema Respiratório/cirurgia , Estudos Retrospectivos
15.
J Mater Chem B ; 5(15): 2726-2738, 2017 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-32264158

RESUMO

Nanoparticles have shown great promise in the development of efficient drug delivery systems, early diagnosis, and high-resolution imaging of hard-to-find diseases, such as early-stage malignant cancer and very rare circulating tumor cells, for pharmaceutical and medical applications. Recently, nanoparticles have been used as intracellular carriers of nano-drugs into targeted cells to release a slowly diffusing drug in the vicinity of the target disease. Several methods such as chemical reagent-based uptake, mechanical bombardment, direct injection, and electroporation have been developed to deliver nanoparticles into cells in a controlled manner. Unlike other methods, electroporation has continued to have great success with respect to the uptake efficiency, post-viability of cells, and high-throughput yield rate for numerous cell applications in association with nanoparticles. In this review, we present recent advances in the delivery of nanoparticles as intracellular carriers by electroporation (NICE) and highlight the salient features of NICE delivery at a multiscale level. We furthermore discuss the current challenges and future perspectives of NICE delivery for clinical applications.

16.
J Korean Med Sci ; 30 Suppl 1: S67-74, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26566360

RESUMO

Neonatal sepsis remains one of the most important causes of death and co-morbidity in very-low-birth-weight (VLBW) infants. The aim of this study was to determine the current incidences of early-onset sepsis (EOS) and late-onset sepsis (LOS), the distribution of pathogens, and the impact of infection on co-morbidities in VLBW infants. We analyzed the data including sepsis episode from 2,386 VLBW infants enrolled in Korean Neonatal Network from January 2013 to June 2014. We defined EOS as a positive blood culture occurring between birth and 7 days of life and LOS after 7 days of life. Sepsis was found in 21.1% of VLBW infants. The risk of sepsis was inversely related to birth weight and gestational age. EOS was found in only 3.6% of VLBW infants, however the mortality rate was as high as 34.1%. EOS was associated with the increased odds for bronchopulmonary dysplasia and intraventricular hemorrhage. The vast majority of EOS was caused by Gram-positive organisms, particularly coagulase-negative staphylococci (30.6%). LOS developed in 19.4% of VLBW infants with a 16.1% mortality rate. Pathogens in LOS were dominated by coagulase-negative staphylococci (38.3%). Twenty-five percent and fifty percent of first LOS episode occurred after 12 days and 20 days from birth, respectively. Younger and smaller VLBW infants showed the earlier occurrence day for the 25% of first LOS episode. This study provides a recent nationwide epidemiology of sepsis in VLBW infants in Korea. Based on this study, successful strategies to reduce infections would improve survival and reduce morbidity.


Assuntos
Recém-Nascido de muito Baixo Peso , Sepse/epidemiologia , Coagulase/metabolismo , Bases de Dados Factuais , Idade Gestacional , Bactérias Gram-Negativas/isolamento & purificação , Bactérias Gram-Positivas/isolamento & purificação , Humanos , Incidência , Recém-Nascido , Estimativa de Kaplan-Meier , República da Coreia/epidemiologia , Fatores de Risco , Sepse/microbiologia , Sepse/mortalidade , Staphylococcus/enzimologia , Staphylococcus/isolamento & purificação
17.
Int J Biol Sci ; 11(8): 879-91, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26157343

RESUMO

In obesity, cardiac insulin resistance is a putative cause of cardiac hypertrophy and dysfunction. In our previous study, we observed that Magnolia extract BL153 attenuated high-fat-diet (HFD)-induced cardiac pathogenic changes. In this study, we further investigated the protective effects of the BL153 bioactive constituent, 4-O-methylhonokiol (MH), against HFD-induced cardiac pathogenesis and its possible mechanisms. C57BL/6J mice were fed a normal diet or a HFD with gavage administration of vehicle, BL153, or MH (low or high dose) daily for 24 weeks. Treatment with MH attenuated HFD-induced obesity, as evidenced by body weight gain, and cardiac pathogenesis, as assessed by the heart weight and echocardiography. Mechanistically, MH treatment significantly reduced HFD-induced impairment of cardiac insulin signaling by preferentially augmenting Akt2 signaling. MH also inhibited cardiac expression of the inflammatory factors tumor necrosis factor-α and plasminogen activator inhibitor-1 and increased the phosphorylation of nuclear factor erythroid-derived 2-like 2 (Nrf2) as well as the expression of a Nrf2 downstream target gene heme oxygenase-1. The increased Nrf2 signaling was associated with decreased oxidative stress and damage, as reflected by lowered malondialdehyde and 3-nitrotyrosine levels. Furthermore, MH reduced HFD-induced cardiac lipid accumulation along with lowering expression of cardiac fatty acid translocase/CD36 protein. These results suggest that MH, a bioactive constituent of Magnolia, prevents HFD-induced cardiac pathogenesis by attenuating the impairment of cardiac insulin signaling, perhaps via activation of Nrf2 and Akt2 signaling to attenuate CD36-mediated lipid accumulation and lipotoxicity.


Assuntos
Compostos de Bifenilo/farmacologia , Dieta Hiperlipídica , Insulina/metabolismo , Lignanas/farmacologia , Magnolia/química , Miocárdio/metabolismo , Obesidade/metabolismo , Transdução de Sinais/efeitos dos fármacos , Animais , Pressão Sanguínea/efeitos dos fármacos , Testes de Função Cardíaca/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , Obesidade/etiologia , Tamanho do Órgão/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos
18.
Pediatr Neonatol ; 56(4): 261-7, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25649722

RESUMO

BACKGROUND: It remains unclear whether the benefit of postnatal corticosteroid as a respiratory rescue therapy outweighs the potential harm of neurodevelopmental impairment (NDI) in very-low-birth-weight infants at risk of bronchopulmonary dysplasia (BPD). METHODS: We reviewed the charts of very-low-birth-weight infants with oxygen dependency for 28 days or more and who survived until 18-22 months' corrected age. Patients were divided into the delayed (≥21 days after birth) dexamethasone therapy (DDT, n=71) and the control (n=60) groups. NDI was defined by the presence of cerebral palsy, Bayley Mental or Psychomotor Developmental Index less than 70, deafness, or blindness. RESULTS: The DDT group was more premature and had worse respiratory morbidities before (ventilator-dependent at 21 days, 69% vs. 17%) and after the DDT (moderate/severe BPD, 41% vs. 15%) than the control group. The risk of NDI did not differ between the DDT and the control groups in the entire cohort (odds ratio and 95% confidence interval, 1.309 [0.530-3.237]) or in the propensity-score-matched cohort (n=62; odds ratio and 95% confidence interval, 1.344 [0.455-3.976]). However, in the subgroup of infants exposed to DDT, the cumulative dexamethasone dose greater than 5.0 mg/kg was significantly associated with NDI. CONCLUSION: Among the very-low-birth-weight infants with BPD, there was no definitely harmful effect of DDT on the neurodevelopmental outcome in the short term. However, considering the potential harm of high cumulative doses of dexamethasone on the developing brain, further studies are needed to determine the optimal dosage of DDT to be administered for the prevention of BPD.


Assuntos
Displasia Broncopulmonar/tratamento farmacológico , Dexametasona/administração & dosagem , Glucocorticoides/administração & dosagem , Recém-Nascido Prematuro , Transtornos do Neurodesenvolvimento/fisiopatologia , Dexametasona/efeitos adversos , Feminino , Glucocorticoides/efeitos adversos , Humanos , Lactente , Recém-Nascido , Recém-Nascido de muito Baixo Peso , Masculino , Transtornos do Neurodesenvolvimento/induzido quimicamente
19.
J Korean Med Sci ; 28(6): 924-8, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23772159

RESUMO

The aims of this study were to investigate whether early arterial blood gas analysis (ABGA) could define the severity of disease in infants with congenital diaphragmatic hernia (CDH). We conducted a retrospective study over a 21-yr period of infants diagnosed with CDH. Outcomes were defined as death before discharge, and extracorporeal membrane oxygenation requirements (ECMO) or death. A total 114 infants were included in this study. We investigated whether simplified prediction formula [PO2-PCO2] values at 0, 4, 8, and 12 hr after birth were associated with mortality, and ECMO or death. The area under curve (AUC) of receiver operating characteristic curve was used to determine the optimum ABGA values for predicting outcomes. The value of [PO2-PCO2] at birth was the best predictor of mortality (AUC 0.803, P < 0.001) and at 4 hr after birth was the most reliable predictor of ECMO or death (AUC 0.777, P < 0.001). The value of [PO2-PCO2] from ABGA early period after birth can reliably predict outcomes in infants with CDH.


Assuntos
Algoritmos , Gasometria , Oxigenação por Membrana Extracorpórea , Hérnias Diafragmáticas Congênitas , Área Sob a Curva , Feminino , Hérnia Diafragmática/mortalidade , Hérnia Diafragmática/fisiopatologia , Humanos , Recém-Nascido , Masculino , Valor Preditivo dos Testes , Curva ROC , Estudos Retrospectivos , Taxa de Sobrevida , Resultado do Tratamento
20.
Biofabrication ; 5(2): 022001, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23403762

RESUMO

Recent advances in the lab-on-a-chip field in association with nano/microfluidics have been made for new applications and functionalities to the fields of molecular biology, genetic analysis and proteomics, enabling the expansion of the cell biology field. Specifically, microfluidics has provided promising tools for enhancing cell biological research, since it has the ability to precisely control the cellular environment, to easily mimic heterogeneous cellular environment by multiplexing, and to analyze sub-cellular information by high-contents screening assays at the single-cell level. Various cell manipulation techniques in microfluidics have been developed in accordance with specific objectives and applications. In this review, we examine the latest achievements of cell manipulation techniques in microfluidics by categorizing externally applied forces for manipulation: (i) optical, (ii) magnetic, (iii) electrical, (iv) mechanical and (v) other manipulations. We furthermore focus on history where the manipulation techniques originate and also discuss future perspectives with key examples where available.


Assuntos
Separação Celular/métodos , Microfluídica/métodos , Eletricidade , Humanos , Hidrodinâmica , Campos Magnéticos , Nanopartículas de Magnetita/química , Células Neoplásicas Circulantes/química , Óptica e Fotônica
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