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1.
Opt Express ; 32(7): 11907-11915, 2024 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-38571028

RESUMEN

We report on stable, long-term operation of a diode-pumped solid-state laser (DPSSL) amplifying 15 ns pulses at 1029.5 nm wavelength to 10 J energy at 100 Hz pulse rate, corresponding to 1 kW average power, with 25.4% optical-to-optical efficiency. The laser was operated at this level for over 45 minutes (∼3 · 105 shots) in two separate runs with a rms energy stability of 1%. The laser was also operated at 7 J, 100 Hz for 4 hours (1.44 · 106 shots) with a rms long-term energy stability of 1% and no need for user intervention. To the best of our knowledge, this is the first time that long-term reliable amplification of a kW-class high energy nanosecond pulsed DPSSL at 100 Hz has been demonstrated.

2.
Circulation ; 145(5): 345-356, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34865500

RESUMEN

BACKGROUND: Understanding the clinical course and short-term outcomes of suspected myocarditis after the coronavirus disease 2019 (COVID-19) vaccination has important public health implications in the decision to vaccinate youth. METHODS: We retrospectively collected data on patients <21 years old presenting before July 4, 2021, with suspected myocarditis within 30 days of COVID-19 vaccination. Lake Louise criteria were used for cardiac MRI findings. Myocarditis cases were classified as confirmed or probable on the basis of the Centers for Disease Control and Prevention definitions. RESULTS: We report on 139 adolescents and young adults with 140 episodes of suspected myocarditis (49 confirmed, 91 probable) at 26 centers. Most patients were male (n=126, 90.6%) and White (n=92, 66.2%); 29 (20.9%) were Hispanic; and the median age was 15.8 years (range, 12.1-20.3; interquartile range [IQR], 14.5-17.0). Suspected myocarditis occurred in 136 patients (97.8%) after the mRNA vaccine, with 131 (94.2%) after the Pfizer-BioNTech vaccine; 128 (91.4%) occurred after the second dose. Symptoms started at a median of 2 days (range, 0-22; IQR, 1-3) after vaccination. The most common symptom was chest pain (99.3%). Patients were treated with nonsteroidal anti-inflammatory drugs (81.3%), intravenous immunoglobulin (21.6%), glucocorticoids (21.6%), colchicine (7.9%), or no anti-inflammatory therapies (8.6%). Twenty-six patients (18.7%) were in the intensive care unit, 2 were treated with inotropic/vasoactive support, and none required extracorporeal membrane oxygenation or died. Median hospital stay was 2 days (range, 0-10; IQR, 2-3). All patients had elevated troponin I (n=111, 8.12 ng/mL; IQR, 3.50-15.90) or T (n=28, 0.61 ng/mL; IQR, 0.25-1.30); 69.8% had abnormal ECGs and arrhythmias (7 with nonsustained ventricular tachycardia); and 18.7% had left ventricular ejection fraction <55% on echocardiogram. Of 97 patients who underwent cardiac MRI at a median 5 days (range, 0-88; IQR, 3-17) from symptom onset, 75 (77.3%) had abnormal findings: 74 (76.3%) had late gadolinium enhancement, 54 (55.7%) had myocardial edema, and 49 (50.5%) met Lake Louise criteria. Among 26 patients with left ventricular ejection fraction <55% on echocardiogram, all with follow-up had normalized function (n=25). CONCLUSIONS: Most cases of suspected COVID-19 vaccine myocarditis occurring in persons <21 years have a mild clinical course with rapid resolution of symptoms. Abnormal findings on cardiac MRI were frequent. Future studies should evaluate risk factors, mechanisms, and long-term outcomes.


Asunto(s)
Vacunas contra la COVID-19/efectos adversos , COVID-19/prevención & control , Miocarditis/diagnóstico por imagen , Miocarditis/fisiopatología , Adolescente , Niño , Electrocardiografía/métodos , Femenino , Humanos , Imagen por Resonancia Cinemagnética/métodos , Masculino , Miocarditis/sangre , Miocarditis/etiología , Estudios Retrospectivos , Factores de Tiempo , Adulto Joven
3.
J Pediatr Nurs ; 73: e618-e623, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37957083

RESUMEN

PURPOSE: Congenital heart disease affects thousands of newborns each year in the United States. Previous United States-based research has explored how sociodemographic factors may impact health outcomes in infants with congenital heart disease; however, their impact on the incidence of congenital heart disease is unclear. We explored the sociodemographic profile related to congenital heart disease to help address health disparities that arise from race and social determinants of health. Defining the sociodemographic factors associated with congenital heart disease will encourage implementation of potential preventative measures. DESIGN AND METHODS: We conducted a secondary analysis of longitudinally collected data comparing 39 infants with congenital heart disease and 30 healthy controls. We used a questionnaire to collect sociodemographic data. Pearson's chi-square test/Fisher's exact tests analyzed the associations among different sociodemographic factors between infants with congenital heart disease and healthy controls. RESULTS: We found a statistically significant difference in maternal education between our 2 groups of infants (p = 0.004). CONCLUSION: Maternal education was associated with congenital heart disease. Future studies are needed to further characterize sociodemographic factors that may predict and impact the incidence of congenital heart disease and to determine possible interventions that may help decrease health disparities regarding the incidence of congenital heart disease. PRACTICE IMPLICATIONS: Understanding the associations between maternal sociodemographic factors and infant congenital heart disease would allow clinicians to identify mothers at higher risk of having an infant with congenital heart disease.


Asunto(s)
Cardiopatías Congénitas , Lactante , Femenino , Recién Nacido , Humanos , Estados Unidos/epidemiología , Cardiopatías Congénitas/diagnóstico , Cardiopatías Congénitas/epidemiología , Madres , Escolaridad , Encuestas y Cuestionarios , Incidencia
5.
J Surg Res ; 280: 273-279, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36030602

RESUMEN

INTRODUCTION: Children with congenital heart disease (CHD) often experience feeding intolerance due to aspiration, inability to tolerate feed volume, or reflux within the first few months of life, requiring a surgically placed gastrostomy tube (GT) for durable enteral access. However, complications such as GT dislodgement, cellulitis, and leakage related to GT use are common. GT-related complications can lead to unscheduled pediatric surgery clinic or emergency room (ER) visits, which can be time consuming for the family and increase overall healthcare costs. We sought to identify factors associated with GT complications within 2 wk after GT surgery and 1-y after discharge home following GT placement in infants with CHD. METHODS: We performed a retrospective cohort study using the Society of Thoracic Surgeons database and electronic medical records from a tertiary children's hospital. We identified infants <1 y old underwent CHD surgery followed by GT surgery between September 2013-August 2018. Demographics, pre-operative feeding regimen, comorbidities, and GT-related utilization were measured. Postoperative GT complications (e.g., GT cellulitis, leakage, dislodgement, obstruction, and granulation tissue) within 2 wk after the GT surgery and an unplanned pediatric surgery clinic or ER visit within 1-y after discharge home were captured. Bivariate comparisons and multivariable logistic regression evaluated factors associated with GT complications and unplanned clinic or ER visits. A Kaplan-Meier failure curve examined the timing of ER/clinic visits. RESULTS: Of 152 infants who underwent CHD then GT surgeries, 66% (N = 101) had postoperative GT complications. Overall, 83 unscheduled clinic visits were identified after discharge, with 37% (N = 31) due to concerns about granulation tissue. Of 137 ER visits, 48% (N = 66) were due to accidental GT dislodgement. Infants who were hospitalized for ≥2 wk after GT surgery had more complications than those discharged home within 2 wk of the GT surgery (40.6% versus 15.7%, P = 0.002). Infants receiving oral nutrition before CHD surgery (38.6% versus 60%, P=<0.001) or with single ventricle defects (19.8% versus 37.3%, P = 0.02) had fewer GT complications. After adjusting for type of cardiac anomaly, infants receiving oral nutrition prior to CHD surgery had a decreased likelihood of GT complications (odds ratio OR 0.46; 95% confidence intervals CI:0.23-0.93). A Kaplan-Meier failure curve demonstrated that 50% of the cohort experienced a complication leading to an unscheduled ER/clinic visit within 6 mo after discharge. CONCLUSIONS: Unplanned visits to the ER or pediatric surgery clinic occur frequently for infants with CHD requiring a surgically placed GT. Oral feedings before cardiac surgery associated with fewer GT complications. Prolonged hospitalization associated with more GT complications. Optimizing outpatient care and family education regarding GT maintenance may reduce unscheduled visits for this high-risk, device-dependent infant population.


Asunto(s)
Gastrostomía , Cardiopatías Congénitas , Humanos , Lactante , Recién Nacido , Niño , Gastrostomía/efectos adversos , Estudios Retrospectivos , Celulitis (Flemón) , Intubación Gastrointestinal/efectos adversos , Cardiopatías Congénitas/cirugía , Cardiopatías Congénitas/complicaciones , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología
6.
Pediatr Cardiol ; 43(7): 1624-1630, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35426499

RESUMEN

Congenital heart disease (CHD) is a common birth defect in the United States. CHD infants are more likely to have smaller head circumference and neurodevelopmental delays; however, the cause is unknown. Altered cerebrovascular hemodynamics may contribute to neurologic abnormalities, such as smaller head circumference, thus we created a novel Cerebrovascular Stability Index (CSI), as a surrogate for cerebral autoregulation. We hypothesized that CHD infants would have an association between CSI and head circumference. We performed a prospective, longitudinal study in CHD infants and healthy controls. We measured CSI and head circumference at 4 time points (newborn, 3, 6, 9 months). We calculated CSI by subtracting the average 2-min sitting from supine cerebral oxygenation (rcSO2) over three consecutive tilts (0-90°), then averaged the change score for each age. Linear regressions quantified the relationship between CSI and head circumference. We performed 177 assessments in total (80 healthy controls, 97 CHD infants). The average head circumference was smaller in CHD infants (39.2 cm) compared to healthy controls (41.6 cm) (p < 0.001) and head circumference increased by 0.27 cm as CSI improved in the sample (p = 0.04) overall when combining all time points. Similarly, head circumference increased by 0.32 cm as CSI improved among CHD infants (p = 0.04). We found CSI significantly associated with head circumference in our sample overall and CHD infants alone, which suggests that impaired CSI may affect brain size in CHD infants. Future studies are needed to better understand the mechanism of interaction between CSI and brain growth.


Asunto(s)
Cardiopatías Congénitas , Cabeza , Cardiopatías Congénitas/complicaciones , Hemodinámica , Humanos , Lactante , Recién Nacido , Estudios Longitudinales , Estudios Prospectivos
7.
Cardiol Young ; 32(8): 1261-1267, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34588090

RESUMEN

OBJECTIVE: To describe outcomes of acute coronavirus disease 2019 in paediatric and young adult patients with underlying cardiac disease and evaluate the association between cardiac risk factors and hospitalisation. STUDY DESIGN: We conducted a retrospective single-institution review of patients with known cardiac disease and positive severe acute respiratory syndrome coronavirus 2 RT-PCR from 1 March, 2020 to 30 November, 2020. Extracardiac comorbidities and cardiac risk factors were compared between those admitted for coronavirus disease 2019 illness and the rest of the cohort using univariate analysis. RESULTS: Forty-two patients with a mean age of 7.7 ± 6.7 years were identified. Six were 18 years of age or more with the oldest being 22 years of age. Seventy-six percent were Hispanic. The most common cardiac diagnoses were repaired cyanotic (n = 7, 16.6%) and palliated single ventricle (n = 7, 16.6%) congenital heart disease. Fourteen patients (33.3%) had underlying syndromes or chromosomal anomalies, nine (21%) had chronic pulmonary disease and eight (19%) were immunosuppressed. Nineteen patients (47.6%) reported no symptoms. Sixteen (38.1%) reported only mild symptoms. Six patients (14.3%) were admitted to the hospital for acute coronavirus disease 2019 illness. Noncardiac comorbidities were associated with an increased risk of hospitalisation (p = 0.02), particularly chronic pulmonary disease (p = 0.01) and baseline supplemental oxygen requirement (p = 0.007). None of the single ventricle patients who tested positive required admission. CONCLUSIONS: Hospitalisations for coronavirus disease 2019 were rare among children and young adults with underlying cardiac disease. Extracardiac comorbidities like pulmonary disease were associated with increased risk of hospitalisation while cardiac risk factors were not.


Asunto(s)
COVID-19 , Cardiopatías , Adolescente , Adulto , COVID-19/epidemiología , Niño , Preescolar , Cardiopatías/epidemiología , Hospitalización , Humanos , Lactante , Estudios Retrospectivos , SARS-CoV-2 , Adulto Joven
8.
Int J Lang Commun Disord ; 57(1): 103-111, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34676948

RESUMEN

BACKGROUND: There is growing understanding of the potential benefits of a multi-method approach to accurately capture language skills of children on the autism spectrum. Tools such as Language ENvironment Analysis (LENA) provide an efficient means of capturing and analysing early child vocalizations (CVs) and the language learning environment. While developed to capture whole-day recordings of child language in naturalistic settings, there is potential utility in capturing, but little knowledge about, primary LENA metrics-including CVs and conversational turns (CTs)-and novel metrics, such as vocalization ratios (VRs), sampled in clinical practice settings where children are often seen. Moreover, recent research indicates that the novel VR may offer a broad indicator of children's developmental level, beyond just their language abilities, a hypothesis yet to be investigated in a large sample of children for whom the LENA was designed (i.e., pre-schoolers). AIMS: To explore the extent to which primary and novel LENA metrics collected during brief one-to-one clinical interaction was a useful indicator of developmental outcomes for children on the autism spectrum. METHODS & PROCEDURES: Participants were recruited as part of an on-going research programme evaluating early intervention outcomes (n = 99; age 14-47 months). Language samples were collected at intake (T1) using the wearable LENA Digital Language Processors during a one-to-one, play-based assessment with a clinician. Direct (Mullen Scales of Early Learning-MSEL) and parent-report (Vineland Adaptive Behavior Scales-VABS) measures of verbal and non-verbal skills were also collected at intake (T1) and again at exit (T2), approximately 12 months later. OUTCOMES & RESULTS: Few correlations were observed between child measures and CVs, a primary LENA metric. The novel VR metric was associated with concurrent direct assessment (MSEL) (and to a lesser extent parent report; VABS) measures of verbal and non-verbal skills, with moderate positive correlations found between VRs and all directly assessed subscale scores. However, VRs did not uniquely contribute to the prediction of child outcomes when baseline skills were also considered. CONCLUSIONS & IMPLICATIONS: The novel VR may provide an insight into autistic children's overall development in addition to their language ability, suggesting that even when collected in a short recording format, LENA might be a useful component of a multi-method assessment approach. WHAT THIS PAPER ADDS: What is already known on the subject To accurately capture language skills of children on the autism spectrum, multi-method approaches, including natural language sampling, are recommended. Tools such as LENA provide an efficient means of capturing and analysing naturalistic child language and the language learning environment. What this paper adds to existing knowledge This study demonstrates the potential benefits, and limitations, of using LENA to augment assessment of young children on the autism spectrum. Specifically, LENA provides a complementary, and low burden, method for capturing child language samples. What are the potential or actual clinical implications of this work? Novel metrics, such as the VR, collected during brief clinical interactions might be a useful component of a multi-method assessment approach for children on the autism spectrum.


Asunto(s)
Trastorno del Espectro Autista , Trastorno Autístico , Trastornos del Desarrollo del Lenguaje , Trastorno del Espectro Autista/complicaciones , Trastorno del Espectro Autista/diagnóstico , Trastorno Autístico/diagnóstico , Niño , Lenguaje Infantil , Preescolar , Humanos , Lactante , Lenguaje , Trastornos del Desarrollo del Lenguaje/complicaciones , Trastornos del Desarrollo del Lenguaje/diagnóstico , Trastornos del Desarrollo del Lenguaje/terapia
9.
Int J Mol Sci ; 23(23)2022 Dec 02.
Artículo en Inglés | MEDLINE | ID: mdl-36499505

RESUMEN

The relationship between maternal risk factors (MRFs) (particularly pre-gravid obesity, diabetes, and hypertension) and congenital heart disease (CHD) to placental and fetal brain outcomes is poorly understood. Here, we tested the hypothesis that MRF and CHD would be associated with reduced intrinsic placental and fetal brain function using a novel non-invasive technique. Pregnant participants with and without MRF and fetal CHD were prospectively recruited and underwent feto-placental MRI. Using intrinsic properties of blood oxygen level dependent imaging (BOLD) we quantified spatiotemporal variance of placenta and fetal brain. MRFs and CHD were correlated with functional characteristics of the placenta and fetal brain. Co-morbid MRF (hypertension, diabetes, and obesity) reduced spatiotemporal functional variance of placenta and fetal brain (p < 0.05). CHD predicted reduced fetal brain temporal variance compared to non-CHD (p < 0.05). The presence of both MRF and CHD was associated with reduced intrinsic pBOLD temporal variance (p = 0.047). There were no significant interactions of MRFs and CHD status on either temporal or spatial variance of intrinsic brain BOLD. MRF and CHD reduced functional characteristic of placenta and brain in fetuses. MRF modification and management during pregnancy may have the potential to not only provide additional risk stratification but may also improve neurodevelopmental outcomes.


Asunto(s)
Cardiopatías Congénitas , Hipertensión , Embarazo , Humanos , Femenino , Placenta , Encéfalo/diagnóstico por imagen , Factores de Riesgo , Obesidad/complicaciones
10.
Neonatal Netw ; 41(4): 200-210, 2022 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-35840337

RESUMEN

Congenital heart disease (CHD) is one of the most common types of birth defects, with 40,000 newborns diagnosed yearly in the United States. This article describes: (1) four common heart defects seen in neonatal intensive care units, (2) the typical medical/nursing care of these neonates, and (3) common surgical management for the defects. Hypoplastic left heart syndrome, dextro-transposition of the great arteries, tetralogy of Fallot, and pulmonary atresia with intact ventricular septum are four common types of CHD requiring NICU admission. Knowledge of these defects will help nurses to appropriately manage and treat neonates with these types of CHD.


Asunto(s)
Cardiopatías Congénitas , Transposición de los Grandes Vasos , Cardiopatías Congénitas/diagnóstico , Cardiopatías Congénitas/cirugía , Humanos , Recién Nacido , Unidades de Cuidado Intensivo Neonatal , Cuidados Preoperatorios
11.
Opt Express ; 29(4): 5607-5623, 2021 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-33726095

RESUMEN

In this paper, we present a model to predict thermal stress-induced birefringence in high energy, high repetition rate diode-pumped Yb:YAG lasers. The model calculates thermal depolarisation as a function of gain medium geometry, pump power, cooling parameters, and input polarisation state. We show that model predictions are in good agreement with experimental observations carried out on a DiPOLE 100 J, 10 Hz laser amplifier. We show that single-pass depolarisation strongly depends on input polarisation state and pumping parameters. In the absence of any depolarisation compensation scheme, depolarisation varies over a range between 5% and 40%. The strong dependence of thermal stress-induced depolarisation on input polarisation indicates that, in the case of multipass amplifiers, the use of waveplates after every pass can reduce depolarisation losses significantly. We expect that this study will assist in the design and optimisation of Yb:YAG lasers.

12.
Opt Lett ; 46(8): 1808-1811, 2021 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-33857075

RESUMEN

We report on the successful demonstration of second and third harmonic conversion of a high pulse energy, high average power 1030 nm diode pumped Yb-doped yttrium aluminum garnet (Yb:YAG) nanosecond pulsed laser in a large aperture lithium triborate (LBO) crystal. We demonstrated generation of 59.7 J at 10 Hz (597 W) at 515 nm (second harmonic) and of 65.0 J at 1 Hz (65 W) at 343 nm (third harmonic), with efficiencies of 66% and 68%, respectively. These results, to the best of our knowledge, represent the highest energy and power reported for frequency conversion to green and UV-A wavelengths.

13.
Int J Lang Commun Disord ; 56(2): 389-401, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33704873

RESUMEN

BACKGROUND: Early reading success is predicated on language and pre-literacy skills. Children who are behind their peers in language and pre-literacy development before formal schooling are less likely to be proficient beginner readers, and difficulties may persist throughout primary school and beyond. We know children experiencing adversity are at greater risk of early language and pre-literacy difficulties; we do not know the prevalence of these difficulties in an Australian adversity context. AIMS: To investigate the prevalence and co-occurrence of language and pre-literacy difficulties in a cohort of Australian 5-year-old children experiencing social adversity. METHODS & PROCEDURES: Data were drawn from a large Australian community-based trial of nurse home visiting (right@home), which aimed to support women experiencing social adversity from pregnancy until their child turned 2 years of age. Social adversity was determined by two of more risk factors: young pregnancy, not living with another adult, no support, poorer health, current smoker, long-term illness, anxious mood, not finishing high school, no household income and no previous employment. Children whose mothers were enrolled in the control group (receiving usual maternal and child healthcare) were included in the current study (n = 359). Language and pre-literacy skills were measured at age 5 using the Clinical Evaluation of Language Fundamental Preschool-Second Edition (CELF-P2) and the School Entry Alphabetic and Phonological Awareness Readiness Test (SEAPART). Language difficulties were defined as ≥ 1.25 standard deviations (SD) below the Australian normative mean on CELF-P2 Core Language scores. Pre-literacy difficulties were defined as children scoring in the Beginner (versus Developing or Competent) criterion-referenced level on the SEAPART First Sound Identification and/or Alphabet Letter Identification subtests. Co-occurrence of language and pre-literacy difficulties was also determined. OUTCOMES & RESULTS: At the 5-year follow-up, 201/359 (56%) children were assessed (mean age = 5.1 years, SD = 0.1). Mean Core Language score for this cohort (91.8, SD = 15.9) was 0.54 SD below the normative mean (100, SD = 15). The proportion of children presenting with language difficulties was 24.9%. Regarding pre-literacy skills, 43.8% of children were 'Beginner' for identifying first sounds and 58.6% for identifying alphabet letters/sounds. There was also considerable overlap whereby 76.7% of children with language difficulties also exhibited pre-literacy difficulties. CONCLUSIONS & IMPLICATIONS: This is the first empirical Australian-based study highlighting the high prevalence and co-occurrence of language and pre-literacy difficulties in preschool children experiencing social adversity. Clinicians should be aware of co-morbid language and pre-literacy difficulties in disadvantaged populations and consider both areas during assessment and intervention planning. What this paper adds What is already known on the subject The prevalence of language and literacy difficulties is substantially higher in cohorts experiencing social adversity when compared with more advantaged families. There is some evidence that adversity also contributes to pre-literacy difficulties, but less is known here. What this paper adds to existing knowledge This study presents new prevalence data showing high rates of language and pre-literacy difficulties for 5-year-old children experiencing adversity within an Australian context. It is the first to explore these skills in a large cohort of pre-schoolers recruited from community settings in Australia. What are the potential or actual clinical implications of this work? In this cohort experiencing adversity, most children who presented with language difficulties likewise exhibited pre-literacy difficulties. This concordance reflects how early oral language and pre-literacy skills develop together. Clinicians should assess both skills in preschool populations-especially those working with children experiencing adversity-to ensure all children have strong foundations to become proficient beginner readers.


Asunto(s)
Trastornos del Desarrollo del Lenguaje , Alfabetización , Adulto , Australia/epidemiología , Preescolar , Femenino , Humanos , Lenguaje , Trastornos del Desarrollo del Lenguaje/diagnóstico , Trastornos del Desarrollo del Lenguaje/epidemiología , Prevalencia , Lectura
14.
Neonatal Netw ; 40(2): 73-79, 2021 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-33731373

RESUMEN

In this review, we describe the near-infrared spectroscopy (NIRS) technology and its clinical use in high-risk neonates in critical care settings. We searched databases (e.g., PubMed, Google Scholar, EBSCOhost) to find studies describing the use of NIRS on critically ill and high-risk neonates. Near-infrared spectroscopy provides continuous noninvasive monitoring of venous oxygen saturation. It uses technology similar to pulse oximetry to measure the oxygen saturation of hemoglobin in a tissue bed to describe the relative delivery and extraction of oxygen. Near-infrared spectroscopy can be a valuable bedside tool to provide clinicians indirect evidence of perfusion. It may prompt early interventions that promote oxygen delivery, which can improve high-risk neonatal outcomes.


Asunto(s)
Oximetría , Espectroscopía Infrarroja Corta , Cuidados Críticos , Humanos , Recién Nacido , Oxígeno
15.
Opt Lett ; 45(10): 2946-2949, 2020 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-32412507

RESUMEN

We report on frequency doubling of high-energy, high-repetition-rate ns pulses from a cryogenically gas cooled, multi-slab Yb:YAG laser system, using a type-I phase-matched lithium triborate (LBO) crystal. Pulse energy of 4.3 J was extracted at 515 nm for a fundamental input of 5.4 J at 10 Hz (54 W), corresponding to a conversion efficiency of 77%. However, during long-term operation, a significant reduction of efficiency (more than 25%) was observed owing to the phase mismatch arising due to the temperature-dependent refractive index change in the crystal. This forced frequent angle tuning of the crystal to recover the second-harmonic generation (SHG) energy. More than a five-fold improvement in energy stability of SHG was observed when the LBO crystal was mounted in an oven, and its temperature was controlled at 27°C. Stable frequency doubling with 0.8% rms energy variation was achieved at a higher input power of 74 W when the LBO temperature was controlled at 50°C.

16.
Dev Med Child Neurol ; 62(4): 506-512, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-31538339

RESUMEN

AIM: To compare language, speech, and voice of children born preterm and at term, and determine relevant predictors of outcome. METHOD: Three hundred infants (150 males, 150 females; 149 born at <30wks' gestation, 151 term-born) were prospectively recruited at birth from the Royal Women's Hospital. We administered the Preschool Language Scales, Fifth Edition, Diagnostic Evaluation of Articulation and Phonology, Grade Roughness Breathiness Asthenia Strain Scale, and Pediatric Voice Handicap Index at 3 years, and compared groups. We examined hypothesized predictors in children born preterm: gestational age at birth, birthweight, sex, chronic lung disease, high social risk, multilingualism, neurodevelopmental diagnosis, and oromotor feeding. RESULTS: Children born preterm had poorer language than children born at term (coefficient -5.43). Speech and voice were similar between groups (coefficients -0.70 to 1.63). Chronic lung disease predicted voice (coefficient 6.05); male sex (coefficients 4.54-6.18), high social risk (coefficient -6.02 to -9.30), and neurodevelopmental diagnosis (coefficients -16.42 to -20.61) predicted language. INTERPRETATION: Children born before 30 weeks' gestation had poorer language than children born at term. Children born preterm with neurodevelopmental disabilities or high social risk experience poorer language outcomes, and would benefit from enrichment of their language environment. WHAT THIS PAPER ADDS: Speech and voice outcomes were similar between children born preterm and at term. Male sex, high social risk, and neurodevelopmental diagnosis predicted language outcomes.


Asunto(s)
Desarrollo Infantil/fisiología , Lenguaje Infantil , Comunicación , Desarrollo del Lenguaje , Trastornos del Lenguaje/diagnóstico , Habla/fisiología , Preescolar , Femenino , Edad Gestacional , Humanos , Recien Nacido Extremadamente Prematuro , Pruebas del Lenguaje , Masculino
17.
Int J Lang Commun Disord ; 54(1): 110-122, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30387273

RESUMEN

BACKGROUND: Variations in parenting, more specifically less responsive and more directive parenting, contribute to language difficulties for children experiencing adversity. Further investigation of associations between specific responsive and directive behaviours and child language is required to understand how behaviours shape language over time within different populations. As language is dyadic, further exploration of how mother-child interactions moderate associations is also important. AIMS: To investigate associations between specific responsive and directive maternal behaviours, the quality of mother-child interaction (fluency and connectedness) and child language in a cohort experiencing adversity. METHODS & PROCEDURES: Pregnant women experiencing adversity were recruited from maternity hospitals in Australia. At 12 months, videos of mother-infant free play were collected. Videos were coded for maternal behaviours and fluency and connectedness (n = 249). At 36 months, child language was measured using a standardized language test. Linear regression models were used to examine associations and the moderating role of fluency and connectedness was explored. OUTCOMES & RESULTS: Responsive yes/no questions were positively associated with language scores. Unsuccessful redirectives were negatively associated with language scores. The moderation effect of fluency and connectedness was equivocal in the current data. CONCLUSIONS & IMPLICATIONS: Findings reproduce and extend previous research highlighting key features of mother-child interactions associated with child language trajectories. Findings also augment knowledge of risk and protective factors related to language for children experiencing adversity and highlight where targeted interventions might be successful.


Asunto(s)
Conducta Infantil , Lenguaje Infantil , Conducta Materna , Relaciones Madre-Hijo , Madres/psicología , Responsabilidad Parental/psicología , Problemas Sociales/psicología , Adulto , Factores de Edad , Preescolar , Escolaridad , Femenino , Humanos , Masculino , Edad Materna , Pobreza/psicología , Estudios Prospectivos , Familia Monoparental/psicología , Desempleo/psicología , Adulto Joven
18.
Hum Brain Mapp ; 39(11): 4593-4610, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-30076775

RESUMEN

Neonates with complex congenital heart disease (CHD) demonstrate microstructural brain dysmaturation, but the relationship with structural network topology is unknown. We performed diffusion tensor imaging (DTI) in term neonates with CHD preoperatively (N = 61) and postoperatively (N = 50) compared with healthy term controls (N = 91). We used network topology (graph) analyses incorporating different weighted and unweighted approaches and subject-specific white matter segmentation to investigate structural topology differences, as well as a voxel-based analysis (VBA) to confirm the presence of microstructural dysmaturation. We demonstrate cost-dependent network inefficiencies in neonatal CHD in the pre- and postoperative period compared with controls, related to microstructural differences. Controlling for cost, we show the presence of increased small-worldness (hierarchical fiber organization) in CHD infants preoperatively, that persists in the postoperative period compared with controls, suggesting the early presence of brain reorganization. Taken together, topological microstructural dysmaturation in CHD infants is accompanied by hierarchical fiber organization during a protracted critical period of early brain development. Our methodology also provides a pipeline for quantitation of network topology changes in neonates and infants with microstructural brain dysmaturation at risk for perinatal brain injury.


Asunto(s)
Encéfalo/diagnóstico por imagen , Cardiopatías Congénitas/diagnóstico por imagen , Encéfalo/crecimiento & desarrollo , Imagen de Difusión Tensora , Femenino , Cardiopatías Congénitas/cirugía , Humanos , Recién Nacido , Masculino , Vías Nerviosas/diagnóstico por imagen , Vías Nerviosas/crecimiento & desarrollo , Estudios Prospectivos
19.
Prenat Diagn ; 38(13): 1042-1048, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30328635

RESUMEN

OBJECTIVE: Anomalous neurological development associated with congenital heart disease (CHD) has been reported as early as third trimester of fetal development. While several studies have characterized variations in CHD neurodevelopmental outcomes in early childhood, these reports are often confounded by postnatal factors such as surgical outcome. Recent studies have focused on the comparing neurological variations between fetuses with CHD and normal controls. In this work, we present a comparison of in utero variations in brain development between fetuses with different types of CHD, by analyzing them under categories of single ventricle versus biventricular cardiac anatomy. METHODS: Using recent advances in fetal magnetic resonance imaging (MRI), we quantify the volumetric trajectories of various brain tissues (such as cortical plate, developing white matter, cerebrospinal fluid [CSF], and cerebellum). RESULTS: Our study is the first to differentiate between intraventricular and extra-axial CSF thereby allowing us to better identify variations in brain composition of the fetuses. CONCLUSIONS: Overall, our findings show that while total brain volume is similar between fetuses with single and biventricular anatomy, they exhibit statistically significant disparity in brain composition.


Asunto(s)
Encéfalo/diagnóstico por imagen , Feto/diagnóstico por imagen , Cardiopatías Congénitas/diagnóstico por imagen , Encéfalo/anomalías , Encéfalo/embriología , Estudios de Casos y Controles , Cerebelo/anomalías , Cerebelo/diagnóstico por imagen , Cerebelo/embriología , Corteza Cerebral/anomalías , Corteza Cerebral/diagnóstico por imagen , Corteza Cerebral/embriología , Circulación Cerebrovascular , Ventrículo Derecho con Doble Salida/complicaciones , Ventrículo Derecho con Doble Salida/diagnóstico por imagen , Ventrículo Derecho con Doble Salida/fisiopatología , Anomalía de Ebstein/diagnóstico por imagen , Anomalía de Ebstein/fisiopatología , Ecocardiografía , Femenino , Cardiopatías Congénitas/complicaciones , Cardiopatías Congénitas/fisiopatología , Humanos , Síndrome del Corazón Izquierdo Hipoplásico/complicaciones , Síndrome del Corazón Izquierdo Hipoplásico/diagnóstico por imagen , Síndrome del Corazón Izquierdo Hipoplásico/fisiopatología , Imagen por Resonancia Magnética , Circulación Placentaria , Embarazo , Segundo Trimestre del Embarazo , Tercer Trimestre del Embarazo , Ultrasonografía Doppler , Ultrasonografía Prenatal , Sustancia Blanca/anomalías , Sustancia Blanca/diagnóstico por imagen , Sustancia Blanca/embriología
20.
Pediatr Cardiol ; 39(7): 1346-1354, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-29796693

RESUMEN

The objective of this study is to evaluate neonatal outcomes of total anomalous pulmonary venous return (TAPVR) and identify fetal echocardiography findings associated with preoperative pulmonary venous obstruction (PPVO). This retrospective study evaluated TAPVR cases from 2005 to 2014 for preoperative and postoperative outcomes based on prenatal diagnosis, PPVO, and heterotaxy syndrome. Fetal pulmonary and vertical vein Dopplers were analyzed as predictors of PPVO. Of 137 TAPVR cases, 12% were prenatally diagnosed; 60% had PPVO, and 21% had heterotaxy. Of the prenatally diagnosed patients, 63% also had heterotaxy. TAPVR repair was performed in 135 cases and survival to discharge was 82% (112/137). Heterotaxy was the only independent predictor of mortality on multiple regression analysis [OR 5.5 (CI 1.3-16.7), p = 0.02]. PPVO was associated with preoperative acidosis, need for inhaled nitric oxide, and more emergent surgery, but not postoperative mortality. Fetal vertical vein Doppler peak velocity > 0.74 m/s mmHg predicted PPVO (93% sensitivity; 83% specificity) while pulmonary vein Doppler did not. TAPVR has severe neonatal morbidity and mortality with low prenatal diagnosis rates in the absence of heterotaxy. Patients with obstructed TAPVR had greater preoperative morbidity, but only heterotaxy was independently associated with increased postoperative mortality. Vertical vein velocity helped prenatally identify those at risk of PPVO.


Asunto(s)
Procedimientos Quirúrgicos Cardiovasculares/métodos , Síndrome de Heterotaxia/complicaciones , Enfermedad Veno-Oclusiva Pulmonar/complicaciones , Síndrome de Cimitarra/diagnóstico por imagen , Ultrasonografía Prenatal/métodos , Procedimientos Quirúrgicos Cardiovasculares/efectos adversos , Procedimientos Quirúrgicos Cardiovasculares/mortalidad , Ecocardiografía Doppler/métodos , Femenino , Síndrome de Heterotaxia/diagnóstico , Síndrome de Heterotaxia/epidemiología , Humanos , Recién Nacido , Masculino , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología , Embarazo , Pronóstico , Circulación Pulmonar , Venas Pulmonares/anomalías , Venas Pulmonares/diagnóstico por imagen , Enfermedad Veno-Oclusiva Pulmonar/diagnóstico por imagen , Enfermedad Veno-Oclusiva Pulmonar/cirugía , Estudios Retrospectivos , Síndrome de Cimitarra/complicaciones , Síndrome de Cimitarra/cirugía , Tasa de Supervivencia , Resultado del Tratamiento
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