Risk factors for complications after emergency surgery for paediatric appendicitis: a national prospective observational cohort study.

Appendicectomy is a common procedure in children with a low risk of mortality, however, complication rates and risk factors are largely unknown. This study aimed to characterise the incidence and epidemiology of postoperative complications in children undergoing appendicectomy in the UK. This multicentre prospective observational cohort study, which included children aged 1-16 y who underwent surgery for suspected appendicitis, was conducted between November 2019 and January 2022. The primary outcome was 30-day postoperative morbidity. Data collected included: patient characteristics; comorbidities; and physiological status. Multivariable regression analysis was used to identify independent risk factors for poor outcomes. Data from 2799 children recruited from 80 hospitals were analysed, of which 185 (7%) developed postoperative complications. Children from black and 'other' minority ethnic groups were at significantly higher risk of poor outcomes: OR (95%CI) 4.13 (1.87-9.08), p < 0.001 and 2.08 (1.12-3.87), p = 0.021, respectively. This finding was independent of socio-economic status and type of appendicitis found on histology. Other risk factors for complications included: ASA physical status ≥ 3 (OR (95%CI) 4.05 (1.70-9.67), p = 0.002); raised C-reactive protein (OR 95%CI 1.01 (1.00-1.01), p < 0.001); pyrexia (OR (95%CI) 1.77(1.20-2.63), p = 0.004); and peri-operative oxygen supplementation (OR (95%CI) 4.20 (1.44-12.24), p = 0.009). In the UK NHS, which is a universally accessible healthcare system, ethnicity, but not socio-economic status, was associated with an increased risk of postoperative complications in children having surgery for acute appendicitis. Further evaluations and interventions are required to address this health inequality in keeping with NHS and international priorities.

Altered Brain Structure in Infants with Turner Syndrome.

Turner syndrome (TS) is a genetic disorder affecting approximately 1:2000 live-born females. It results from partial or complete X monosomy and is associated with a range of clinical issues including a unique cognitive profile and increased risk for certain behavioral problems. Structural neuroimaging studies in adolescents, adults, and older children with TS have revealed altered neuroanatomy but are unable to identify when in development differences arise. In addition, older children and adults have often been exposed to years of growth hormone and/or exogenous estrogen therapy with potential implications for neurodevelopment. The study presented here is the first to test whether brain structure is altered in infants with TS. Twenty-six infants with TS received high-resolution structural MRI scans of the brain at 1 year of age and were compared to 47 typically developing female and 39 typically developing male infants. Results indicate that the typical neuroanatomical profile seen in older individuals with TS, characterized by decreased gray matter volumes in premotor, somatosensory, and parietal-occipital cortex, is already present at 1 year of age, suggesting a stable phenotype with origins in the prenatal or early postnatal period.

Functional hemodynamic testing in pregnancy: recommendations of the International Working Group on Maternal Hemodynamics.

In the general population, functional hemodynamic testing, such as that during submaximal aerobic exercise and isometric handgrip, and the cold pressor test, has long been utilized to unmask abnormalities in cardiovascular function. During pregnancy, functional hemodynamic testing places additional demands on an already stressed maternal cardiovascular system. Dysfunctional responses to such tests in early pregnancy may predict the development of hypertensive disorders that develop later in gestation. For each of the above functional hemodynamic tests, these recommendations provide a description of the test, test protocol and equipment required, and an overview of the current understanding of clinical application during pregnancy. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.

Low-loss arrayed waveguide grating at 760 nm.

An arrayed waveguide grating (AWG) at 760 nm is demonstrated with an insertion loss smaller than 0.5 dB. Interface roughness and waveguide length errors contribute much more to scattering loss and phase errors at 760 nm than at longer wavelengths, thus requiring improved design and fabrication. This Letter details how this is achieved by minimizing interfacial scattering, grating side-order excitation, and phase errors in the AWG. With silicon nitride core and silicon dioxide clad waveguides on silicon, this AWG is compatible with heterogeneously integrated lasers for on-chip spectral beam combining.

Fully integrated hybrid silicon two dimensional beam scanner.

In this work we present the first fully-integrated free-space beam-steering chip using the hybrid silicon platform. The photonic integrated circuit (PIC) consists of 164 optical components including lasers, amplifiers, photodiodes, phase tuners, grating couplers, splitters, and a photonic crystal lens. The PIC exhibited steering over 23° x 3.6° with beam widths of 1° x 0.6°.

Mass-like peripheral zone enhancement on CT is predictive of higher-grade (Gleason 4 + 3 and higher) prostate cancer.

PURPOSE: To determine whether focal peripheral zone enhancement on routine venous-phase CT is predictive of higher-grade (Gleason 4 + 3 and higher) prostate cancer. MATERIALS AND METHODS: IRB approval was obtained and informed consent waived for this HIPAA-compliant retrospective study. Forty-three patients with higher-grade prostate cancer (≥Gleason 4 + 3) and 96 with histology-confirmed lower-grade (≤Gleason 3 + 4 [n = 47]) or absent (n = 49) prostate cancer imaged with venous-phase CT comprised the study population. CT images were reviewed by ten blinded radiologists (5 attendings, 5 residents) who scored peripheral zone enhancement on a scale of 1 (benign) to 5 (malignant). Mass-like peripheral zone enhancement was considered malignant. Likelihood ratios (LR) and specificities were calculated. Multivariate conditional logistic regression analyses were conducted. RESULTS: Scores of "5" were strongly predictive of higher-grade prostate cancer (pooled LR+ 9.6 [95% CI 5.8-15.8]) with rare false positives (pooled specificity: 0.98 [942/960, 95% CI 0.98-0.99]; all 10 readers had specificity ≥95%). Attending scores of "5" were more predictive than resident scores of "5" (LR+: 14.7 [95% CI 5.8-37.2] vs. 7.6 [95% CI 4.2-13.7]) with similar specificity (0.99 [475/480, 95% CI 0.98-1.00] vs. 0.97 [467/480, 95% CI 0.96-0.99]). Significant predictors of an assigned score of "5" included presence of a peripheral zone mass (p < 0.0001), larger size (p < 0.0001), and less reader experience (p = 0.0008). Significant predictors of higher-grade prostate cancer included presence of a peripheral zone mass (p = 0.0002) and larger size (p < 0.0001). CONCLUSION: Focal mass-like peripheral zone enhancement on routine venous-phase CT is specific and predictive of higher-grade (Gleason 4 + 3 and higher) prostate cancer.

Heterogeneously integrated III-V-on-silicon multibandgap superluminescent light-emitting diode with 290 nm optical bandwidth.

A broadband superluminescent III-V-on-silicon light-emitting diode (LED) was realized. To achieve the large bandwidth, quantum well intermixing and multiple die bonding of InP on a silicon photonic waveguide circuit were combined for the first time, to the best of our knowledge. The device consists of four sections with different bandgaps, centered around 1300, 1380, 1460, and 1540 nm. The fabricated LEDs were connected on-chip in a serial way, where the light generated in the smaller bandgap sections travels through the larger bandgap sections. By balancing the pump current in the four LEDs, we achieved 292 nm of 3 dB bandwidth and an on-chip power of -8 dBm.

Search for solar axions by the CERN axion solar telescope with 3He buffer gas: closing the hot dark matter gap.

The CERN Axion Solar Telescope has finished its search for solar axions with (3)He buffer gas, covering the search range 0.64 eV ≲ ma ≲ 1.17 eV. This closes the gap to the cosmological hot dark matter limit and actually overlaps with it. From the absence of excess x rays when the magnet was pointing to the Sun we set a typical upper limit on the axion-photon coupling of gaγ ≲ 3.3 × 10(-10) GeV(-1) at 95% C.L., with the exact value depending on the pressure setting. Future direct solar axion searches will focus on increasing the sensitivity to smaller values of gaγ, for example by the currently discussed next generation helioscope International AXion Observatory.

Homozygous deletion of the human insulin receptor gene results in leprechaunism.

Homozygous inactivation of a gene, as is frequently performed to generate mouse models, provides an opportunity to elucidate the role that the gene plays in normal physiology. However, studies of human disease provide direct insight into the effect of inactivating mutations in man. In this investigation, we have identified a one year-old boy from a consanguineous pedigree who is homozygous for deletion of the insulin receptor gene resulting in leprechaunism. Contrary to previous predictions, the complete deletion of the insulin receptor gene is compatible with life.

Congenital diaphragmatic hernia.

Infants with congenital diaphragmatic hernia (CDH) have significant mortality and long-term morbidity. Only 60-70% survive and usually those in high-volume centres. The current Task Force, therefore, has convened experts to evaluate the current literature and make recommendations on both the antenatal and post-natal management of CDH. The incidence of CDH varies from 1.7 to 5.7 per 10,000 live-born infants depending on the study population. Antenatal ultrasound scanning is routine and increasingly complemented by the use of magnetic resonance imaging. For isolated CDH, antenatal interventions should be considered, but the techniques need vigorous evaluation. After birth, management protocols are often used and have improved outcome in nonrandomised studies, but immediate intubation at birth and gentle ventilation are important. Pulmonary hypertension is common and its optimal management is crucial as its severity predicts the outcome. Usually, surgery is delayed to allow optimal medical stabilisation. The role of minimal invasive post-natal surgery remains to be further defined. There are differences in opinion about whether extracorporeal membrane oxygenation improves outcome. Survivors of CDH can have a high incidence of comorbidities; thus, multidisciplinary follow-up is recommended. Multicentre international trials are necessary to optimise the antenatal and post-natal management of CDH patients.

Hybrid III/V silicon photonic source with integrated 1D free-space beam steering.

A chip-scale optical source with integrated beam steering is demonstrated. The chip was fabricated using the hybrid silicon platform and incorporates an on-chip laser, waveguide splitter, amplifiers, phase modulators, and surface gratings to comprise an optical phased array with beam steering across a 12° field of view in one axis. Tuning of the phased array is used to achieve 1.8°(steered axis)×0.6°(nonsteered axis) beam width with 7 dB background suppression for arbitrary beam direction within the field of view.

Effect of exercise intensity and duration on capillary glucose responses in pregnant women at low and high risk for gestational diabetes.

BACKGROUND: Exercise may influence glucose metabolism during pregnancy. We examined the effect of exercise intensity and duration on capillary glucose responses in pregnant women at low and high risk for gestational diabetes mellitus (GDM) who followed a modified GDM meal plan. METHODS: Randomization occurred at study entry (16-20 weeks' gestation) into a low-intensity [30% heart rate reserve, low risk-30%I, n = 12; high risk-30%I, n = 11] or vigorous-intensity (70% heart rate reserve, low risk-70%I, n = 12; R-70%I, n = 11) exercise program with similar nutritional control. Exercise consisted of walking three to four times a week, gradually increasing time from 25 to 40 min/session. Free-living capillary glucose concentrations were measured once a week pre-exercise and post-exercise. RESULTS: Capillary glucose responses to exercise were strongly influenced by an interaction between GDM risk, exercise duration and exercise intensity (p = 0.006). Decreases in glucose concentrations were observed after 25 (4 ± 13%), 35 (21 ± 12%) and 40 min (15 ± 18%) of walking in high risk-30%I women, with the most noticeable decline after 35 and 40 min. In the high risk-70%I, glucose concentrations decreased significantly only after 25 (22 ± 14%) and 35 min (7 ± 23%) and increasing the exercise time attenuated glucose concentrations decline. In low risk women, regardless of exercise intensity and duration, decreases in glucose concentrations were significant and similar. CONCLUSION: To achieve the best decline in glucose concentrations, pregnant women who follow a modified GDM meal plan should walk for 25 min/session at vigorous intensity or for 35-40 min/session at low intensity if they are at risk for GDM and for at least 25 min at either low or vigorous intensity if they are at low risk for GDM.

Antenatal and postnatal management of congenital cystic adenomatoid malformation.

Congenital thoracic malformations (CTMs) are a heterogeneous group of rare disorders that may involve the airways or lung parenchyma. The authors have focused on the condition that causes the most controversy, namely, congenital cystic adenomatoid malformation (CCAM). The reported incidence is 3.5 and 0.94 per 10,000 live births for CTMs and CCAMs respectively. Ultrasound is the antenatal imaging modality of choice for screening for CCAMs whilst magnetic resonance imaging is complimentary for morphological and volumetric evaluation of the foetal lung. Most CCAMs are detected antenatally with only a small proportion presenting postnatally. Only a few CCAMs cause foetal problems, with foetal hydrops being the best predictor of death. Although many CCAMs regress during pregnancy, most remain detectable postnatally by CT scans. Surgical excision of symptomatic lesions is relatively straightforward, but management of asymptomatic lesions is controversial. Some surgeons adopt a "wait and see" approach operating only on those patients who develop symptoms, but others operate on asymptomatic patients usually within the first year of life. Due to the potential of malignant transformation, children should have long term follow up. There is an urgent need to delineate the natural history of antenatally detected CCAMs to guide future management.

Walking program of low or vigorous intensity during pregnancy confers an aerobic benefit.

Walking is the most popular activity during pregnancy and may confer an aerobic benefit. However, the minimum intensity threshold of a maternal walking program for an aerobic conditioning response is unknown. The purpose was to examine the effect of a walking program of a low-intensity (LI, 30% heart rate reserve, HRR) or vigorous-intensity (VI, 70%HRR) on maternal cardiorespiratory responses to a standard submaximal treadmill test. Normal weight pregnant women were randomized at study entry (16-20 weeks of gestation) to the LI (n=23) or VI (n=21) walking program, with nutritional control. Participants performed a steady-state treadmill exercise test at their prescribed intensity pre- and post-intervention (34-36 weeks) to evaluate changes in cardiorespiratory responses. Increasing body mass due to pregnancy was similar between the groups throughout the study. From pre- to post-intervention, relative (mL kg - 1 min - 1) VO2 and VCO2 during steady-state submaximal treadmill exercise did not change in the LI group but decreased in the VI group (- 1.25±2.71, p=0.02 and - 1.50±2.64, p=0.005, respectively). Both groups presented increases in oxygen pulse (p≤0.002). Our results showed that the energy cost of walking was not affected by the increase in maternal body weight in the LI group and was decreased in the VI group, suggesting an aerobic conditioning response in both groups, although the VI group presented a greater response. All women presented similar body mass throughout the intervention and delivered healthy babies, indicating that a prenatal walking program of low or vigorous intensity, combined with healthy eating habits, is safe and beneficial to the mother and fetus.

Search for Dark Matter Axions with CAST-CAPP.

The CAST-CAPP axion haloscope, operating at CERN inside the CAST dipole magnet, has searched for axions in the 19.74 µeV to 22.47 µeV mass range. The detection concept follows the Sikivie haloscope principle, where Dark Matter axions convert into photons within a resonator immersed in a magnetic field. The CAST-CAPP resonator is an array of four individual rectangular cavities inserted in a strong dipole magnet, phase-matched to maximize the detection sensitivity. Here we report on the data acquired for 4124 h from 2019 to 2021. Each cavity is equipped with a fast frequency tuning mechanism of 10 MHz/ min between 4.774 GHz and 5.434 GHz. In the present work, we exclude axion-photon couplings for virialized galactic axions down to gaγγ = 8 × 10-14 GeV-1 at the 90% confidence level. The here implemented phase-matching technique also allows for future large-scale upgrades.

Role of pressure and pancreatic reflux in the aetiology of choledochal malformation.

BACKGROUND: The aetiology of choledochal malformation is not known. Babbitt's hypothesis remains a popular concept, and assumes that activated pancreatic juice refluxes through the common pancreatobiliary channel causing mural damage and subsequent biliary dilatation. This hypothesis was tested clinically by evaluating the relationship between epithelial histology, choledochal pressure and degree of pancreatic reflux. METHODS: Children with choledochal malformation (cystic, type 1c; fusiform, type 1f; both intrahepatic and extrahepatic dilatation, type 4) operated on between January 1999 and October 2009 were identified. Where practical, choledochal pressure was measured on entry to the abdominal cavity, by puncture of the common bile duct, and bile was sampled for amylase content. Archival bile duct sections were scored using a semiquantitative epithelial lining/mural score (ELMS). RESULTS: A total of 90 children with choledochal malformations were operated on during the study interval. Histology was available for 73 children (median age 2·9 (interquartile range 1·3-7·9) years), 29 with type 1c, 31 with type 1f and 13 with type 4 malformations. There was a significant stepwise increase in pressure with choledochal morphology (median pressure 13, 17 and 20 mmHg for types 1f, 1c and 4 respectively; P = 0·037). There was an inverse relationship between choledochal pressure and bile amylase activity (r(s) = - 0·45, P < 0·001). High ELMS values were associated with higher choledochal pressure (P = 0·057) and low bile amylase activity (P = 0·002). CONCLUSION: High choledochal pressure (not bile amylase) was associated with more severe histopathological changes and choledochal morphology. These findings suggest that distal bile duct obstruction (and therefore high intraluminal pressure) contributes more to the key features of choledochal malformation than does pancreatic reflux.

Search for sub-eV mass solar axions by the CERN Axion Solar Telescope with 3He buffer gas.

The CERN Axion Solar Telescope (CAST) has extended its search for solar axions by using (3)He as a buffer gas. At T=1.8 K this allows for larger pressure settings and hence sensitivity to higher axion masses than our previous measurements with (4)He. With about 1 h of data taking at each of 252 different pressure settings we have scanned the axion mass range 0.39 eV≲m(a)≲0.64 eV. From the absence of excess x rays when the magnet was pointing to the Sun we set a typical upper limit on the axion-photon coupling of g(aγ)≲2.3×10(-10) GeV(-1) at 95% C.L., the exact value depending on the pressure setting. Kim-Shifman-Vainshtein-Zakharov axions are excluded at the upper end of our mass range, the first time ever for any solar axion search. In the future we will extend our search to m(a)≲1.15 eV, comfortably overlapping with cosmological hot dark matter bounds.

Three-dimensional ultrasound fetal lung volumes and infant respiratory outcome: a prospective observational study.

OBJECTIVE: To determine if fetal lung volumes (FLVs), determined by three-dimensional rotational ultrasound and virtual organ computer-aided analysis software (vocal), correlated with neonatal respiratory outcomes in surviving infants who had a high risk [fetuses with congenital diaphragmatic hernia (CDH)], lower risk [fetuses with anterior wall defects (AWDs)] and no risk (controls) of abnormal antenatal lung growth. DESIGN: Prospective observational study. SETTING: Tertiary fetal medicine and neonatal intensive care units. POPULATION: Sixty fetuses (25 with CDH, 25 with AWDs and ten controls). METHODS: FLVs were measured and expressed as the percentage of the observed compared with the expected for gestational age. MAIN OUTCOME MEASURES: Neonatal respiratory outcome was determined by the duration of supplemental oxygen, mechanical ventilation and dependencies, and assessment of lung volume using a gas dilution technique to measure functional residual capacity (FRC). RESULTS: The infants with CDH had lower FLV results than both the infants with AWDs (P=0.05) and the controls (P<0.05). The infants with CDH had longer durations of mechanical ventilation (P<0.001) and supplementary oxygen (P<0.001) dependence, compared with infants with AWDs. The infants with CDH had a lower median FRC than both the infants with AWDs (P<0.001) and the controls (P<0.001). FLV results correlated significantly with the durations of dependency on ventilation (r= -0.744, P<0.01) and oxygen (r= -0.788, P<0.001), and with FRC results (r=0.429, P=0.001). CONCLUSIONS: These results suggest that FLVs obtained using three-dimensional rotational ultrasound might be useful in predicting neonatal respiratory outcome in surviving infants who had varying risks of abnormal lung growth. Larger and more comprehensive studies are needed to clarify the role that lung volume measurements have in assessing lung function and growth.

HIV-1 variation diminishes CD4 T lymphocyte recognition.

Effective long-term antiviral immunity requires specific cytotoxic T lymphocytes and CD4(+) T lymphocyte help. Failure of these helper responses can be a principle cause of viral persistence. We sought evidence that variation in HIV-1 CD4(+) T helper epitopes might contribute to this phenomenon. To determine this, we assayed fresh peripheral blood mononuclear cells from 43 asymptomatic HIV-1(+) patients for proliferative responses to HIV-1 antigens. 12 (28%) showed a positive response, and we went on to map dominant epitopes in two individuals, to p24 Gag restricted by human histocompatibility leukocyte antigen (HLA)-DR1 and to p17 Gag restricted by HLA-DRB52c. Nine naturally occurring variants of the p24 Gag epitope were found in the proviral DNA of the individual in whom this response was detected. All variants bound to HLA-DR1, but three of these peptides failed to stimulate a CD4(+) T lymphocyte line which recognized the index sequence. Antigenic variation was also detected in the p17 Gag epitope; a dominant viral variant present in the patient was well recognized by a specific CD4(+) T lymphocyte line, whereas several natural mutants were not. Importantly, variants detected at both epitopes also failed to stimulate fresh uncultured cells while index peptide stimulated successfully. These results demonstrate that variant antigens arise in HIV-1(+) patients which fail to stimulate the T cell antigen receptor of HLA class II-restricted lymphocytes, although the peptide epitopes are capable of being presented on the cell surface. In HIV-1 infection, naturally occurring HLA class II-restricted altered peptide ligands that fail to stimulate the circulating T lymphocyte repertoire may curtail helper responses at sites where variant viruses predominate.