Association between fetal growth restriction and stillbirth in twin compared with singleton pregnancies.

OBJECTIVES: Twin pregnancies are at higher risk of stillbirth compared to singletons. Fetal growth restriction (FGR) is a major cause of perinatal mortality, but its impact on twins vs singletons remains unclear. The primary objective of this study was to investigate the association of FGR and small-for-gestational age (SGA) with stillbirth in twin compared with singleton pregnancies. A secondary objective was to assess these associations stratified by gestational age at delivery. Furthermore, we aimed to compare the associations of FGR and SGA with stillbirth in twin pregnancies using twin-specific vs singleton birth-weight charts, stratified by chorionicity. METHODS: This was a retrospective cross-sectional study of pregnancies receiving obstetric care and giving birth between 1999 and 2022 at St George's Hospital, London, UK. The exclusion criteria included triplet and higher-order pregnancies, those resulting in miscarriage or live birth at ≤ 23 + 6 weeks, termination of pregnancy and missing data regarding birth weight or gestational age at birth. Birth-weight data were collected and FGR and SGA were defined as birth weight <5th and <10th centiles, respectively. While standard logistic regression was used for singleton pregnancies, the association of FGR and SGA with stillbirth in twin pregnancies was investigated using mixed-effects logistic regression models. For twin pregnancies, intercepts were allowed to vary for twin pairs to account for intertwin dependency. Analyses were stratified by gestational age at delivery and chorionicity. Statistical significance was set at P ≤ 0.001. RESULTS: The study included 95 342 singleton and 3576 twin pregnancies. There were 494 (0.52%) stillbirths in singleton and 41 (1.15%) stillbirths in twin pregnancies (17 dichorionic and 24 monochorionic). SGA and FGR were associated significantly with stillbirth in singleton pregnancies across all gestational ages at delivery: the odds ratios (ORs) for SGA and FGR were 2.36 ((95% CI, 1.78-3.13), P < 0.001) and 2.67 ((95% CI, 2.02-3.55), P < 0.001), respectively, for delivery before 32 weeks; 2.70 ((95% CI, 1.71-4.31), P < 0.001) and 2.82 ((95% CI, 1.78-4.47), P < 0.001), respectively, for delivery between 32 and 36 weeks; and 3.85 ((95% CI, 2.83-5.21), P < 0.001) and 4.43 ((95% CI, 3.16-6.12), P < 0.001), respectively, for delivery after 36 weeks. In twin pregnancies, when stratified by gestational age at delivery, both SGA and FGR determined by twin-specific birth-weight charts were associated with increased odds of stillbirth for those delivered before 32 weeks (SGA: OR, 3.87 (95% CI, 1.56-9.50), P = 0.003 and FGR: OR, 5.26 (95% CI, 2.11-13.01), P = 0.001), those delivered between 32 and 36 weeks (SGA: OR, 6.67 (95% CI, 2.11-20.41), P = 0.001 and FGR: OR, 9.54 (95% CI, 3.01-29.40), P < 0.001) and those delivered beyond 36 weeks (SGA: OR, 12.68 (95% CI, 2.47-58.15), P = 0.001 and FGR: OR, 23.84 (95% CI, 4.62-110.25), P < 0.001). However, the association of stillbirth with SGA and FGR in twin pregnancies was non-significant when diagnosis was based on singleton charts (before 32 weeks: SGA, P = 0.014 and FGR, P = 0.005; 32-36 weeks: SGA, P = 0.036 and FGR, P = 0.008; after 36 weeks: SGA, P = 0.080 and FGR, P = 0.063). CONCLUSION: Our study demonstrates that SGA and, especially, FGR are associated significantly with an increased risk of stillbirth across all gestational ages in singleton pregnancies, and in twin pregnancies when twin-specific birth-weight charts are used. © 2024 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Integrated programmable spectral filter for frequency-multiplexed neuromorphic computers.

Artificial neural networks (ANN) are a groundbreaking technology massively employed in a plethora of fields. Currently, ANNs are mostly implemented through electronic digital computers, but analog photonic implementations are very interesting mainly because of low power consumption and high bandwidth. We recently demonstrated a photonic neuromorphic computing system based on frequency multiplexing that executes ANNs algorithms as reservoir computing and Extreme Learning Machines. Neuron signals are encoded in the amplitude of the lines of a frequency comb, and neuron interconnections are realized through frequency-domain interference. Here we present an integrated programmable spectral filter designed to manipulate the optical frequency comb in our frequency multiplexing neuromorphic computing platform. The programmable filter controls the attenuation of 16 independent wavelength channels with a 20 GHz spacing. We discuss the design and the results of the chip characterization, and we preliminary demonstrate, through a numerical simulation, that the produced chip is suitable for the envisioned neuromorphic computing application.

Analysis of skull bone thickness during growth: an anatomical guide for safe pin placement in halo fixation.

PURPOSE: To assess skull bone thickness from birth to skeletal maturity at different sites to provide a reference for the correct selection of pin type and pin placement according to age. METHODS: 270 children and adolescents (age: 0-17 years) with a normal CT scan obtained at Emergency Department for other medical reasons were included. Skull thickness was measured on the axial plane CT scans at eight different sites of the vault: midline anterior (A) and posterior (P), right and left lateral (L), antero-lateral (AL), postero-lateral (PL). RESULTS: From birth to skeletal maturity, L thickness was increased significantly less (+ 58%) compared with AL (+ 205%), P (+ 233%), PL (+ 247%), and A (+ 269%) thickness (P < 0.01). At the end of growth, the thickest and thinnest points of the vault (absolute value) were found at the P and L measurement sites, respectively (P < 0.01). Children aged < 4 years exhibited the highest variability in AL and PL skull bone thickness, with thickness < 3 mm observed in 85% (64/75 patients) and 92% (69/75 patients) of cases, respectively. CONCLUSION: We recommend that the tip of the pin should not exceed 2-3 mm in children aged < 4, and 4 mm in children aged 4-6 years, to decrease the risk of inner table perforation. After the age of 7 years and 13 years, standard-sized pin tips (5 and 6 mm, respectively) may be safely used. Children aged < 4 years show significant variability in skull thickness, and therefore a CT scan may be required for this particular age group.

Incidence of Incisional Hernia After Emergency Subcostal Unilateral Laparotomy: Does Augmentation Prophylaxis Play a Role?

BACKGROUND: Few data are available about the frequency of incisional hernia in an emergency subcostal laparotomy. Our objective is to analyze the incidence of incisional hernia after emergency subcostal laparotomy and evaluate if prophylactic mesh could help prevent it. METHODS: This study is a monocentric retrospective analysis following STROBE guideline statements of all patients who underwent an emergency subcostal laparotomy between January 2011 and July 2017 in our University Hospital. We compared complications and incidence of incisional hernia between patients who received sutures (Group S; N = 203) and patients with prophylactic onlay mesh (Group M; N = 80). A multivariate risk factor analysis of incisional hernia was performed. An incisional hernia-estimated risk calculator equation was created. RESULTS: A total of 283 patients were analyzed. There were 80 patients in Group M and 203 in Group S. In short-term outcomes, length of surgery (213 ± 115 min vs 165 ± 73.3 min, P = 0.001) and hospital stay (16.4 ± 18.7 vs 11.6 days ± 13.4, P = 0.038) were longer in Group M. Long-term follow-up was conducted in 207 patients with a mean follow-up time of 39.3 ± 23 months. Incisional hernia was detected in 29 (19.1%) patients in Group S but in only two (3.8%) patients in Group M (P = 0.008). In the multivariate analysis, a risk factor analysis included wound infection (4.91 HR (2.12-11.4); P < 0.001), previous hernia repair (2.86 HR (1.24-6.61); P = 0.014), and shock (2.64 HR (1.01-6.93); P = 0.048). CONCLUSIONS: The incidence of incisional hernia after emergency subcostal laparotomy is high. Risk factors are wound infection, shock, and previous hernia surgery. The use of prophylactic mesh augmentation was safe and reduced the incidence of incisional hernia.

Correction to: Incidence of Incisional Hernia After Emergency Subcostal Unilateral Laparotomy: Does Augmentation Prophylaxis Play a Role?

In the original article some of the column headings in Tables 1-4 were mislabeled.

Correction to: Analysis of skull bone thickness during growth: an anatomical guide for safe pin placement in halo fixation.

Unfortunately, the author group has been incorrectly listed by the first name instead of the family name in the original publication. The complete correct author group should read as follows.

Spectral shapes of Ar-broadened HCl lines in the fundamental band by classical molecular dynamics simulations and comparison with experiments.

Spectral shapes of isolated lines of HCl perturbed by Ar are investigated for the first time using classical molecular dynamics simulations (CMDS). Using reliable intermolecular potentials taken from the literature, these CMDS provide the time evolution of the auto-correlation function of the dipole moment, whose Fourier-Laplace transform leads to the absorption spectrum. In order to test these calculations, room temperature spectra of various lines in the fundamental band of HCl diluted in Ar are measured, in a large pressure range, with a difference-frequency laser spectrometer. Comparisons between measured and calculated spectra show that the CMDS are able to predict the large Dicke narrowing effect on the shape of HCl lines and to satisfactorily reproduce the shapes of HCl spectra at different pressures and for various rotational quantum numbers.

Evaluation of the psychometric properties of the health care providers' pain and impairment relationship scale (HC-PAIRS) in health professionals and university students from Chile and Colombia.

Background: Chronic back pain is a frequent and disabling health problem. There is evidence that ignorance and erroneous beliefs about chronic low back pain among health professionals interfere in the treatment of people who suffer from it. The Health Care Providers' Pain and Impairment Relationship Scale (HC-PAIRS) has been one of the most used scale to assess these misbeliefs, but no studies have been reported in Latin America. Method: We studied the factorial structure of the HC-PAIRS in health personnel and health sciences university students in two Latin American countries: Colombia (n = 930) and Chile (n = 190). Spain's data was taken of the original study of the Spanish version of the HC-PAIRS (171 Physiotherapy students). Additionally, the measurement invariance of this scale among Chile, Colombia and Spain was evaluated by calculating three nested models: configural, metric and scalar. We used a Confirmatory Factor Analysis (CFA) in both Latin American samples, with Maximum Likelihood Robust (MLR) estimation to estimate the parameters. For the final model in each sample, reliability was assessed with the Composite Reliability (CR) index, and to obtain the proportion of variance explained by the scale the Average Variance Extracted (AVE) was calculated. Results: The one-factor solution shows an acceptable fit in both countries after deleting items 1, 6, and 14. For the resulting scale, the CR value is adequate, but the AVE is low. There is scalar invariance between Chile and Colombia, but not between these two countries and Spain. Conclusions: HC-PAIRS is useful for detecting misconceptions about the relationship between chronic low back pain that would cause health personnel to give wrong recommendations to patients. However, it has psychometric weaknesses, and it is advisable to obtain other evidence of validity.

Bifidobacterium animalis subsp. lactis BLa80 regulates the intestinal habit in adults with chronic constipation: a multicentre, randomised, double-blind, placebo-controlled study.

Treatment with probiotics can help manage chronic constipation by softening the stools and possibly acting synergistically with front-line treatments. We assessed the efficacy of Bifidobacterium animalis subsp. lactis BLa80 in maltodextrin as a food supplement in regulating the intestinal habit of subjects with chronic constipation with type 1 or 2 stools on the Bristol scale index and/or less than three stools per week. A multicentre, randomised, double-blind, placebo-controlled clinical trial was carried out in subjects aged 18 and over with chronic constipation. The study enrolled forty-six subjects who were randomised one-to-one to receive the potential probiotic in maltodextrin (n = 23) or a placebo (n = 23). Investigators assessed changes in intestinal habits by analysing the mean number of weekly stools and the stool types according to the Bristol Scale. Patients reported constipation symptoms with PAC-SYM (patient assessment of constipation - symptoms), and the impact on quality of life with PAC-QoL (patient assessment of constipation - quality of life) and GI-QLI (gastrointestinal quality of life index). Patients on the intervention group showed a greater tendency to normalise the type of stools than those in the placebo group. This difference towards regular stool types (type 3 and 4) was statistically significant at weeks 8 and 12 relative to week 4 (P-values = 0.006 and 0.027, respectively). The proportion of constipated patients in the experimental group dropped over time, while the rate slightly increased in the placebo group in a statistically significant manner at week 12 relative to week 4 ( P = 0.037). Overall, the present study shows oral intake of B. animalis subsp. lactis BLa80 in maltodextrin for 12 weeks improves intestinal habits in subjects with chronic constipation. Our study provides evidence to the efficacy and safety use of this formulation as an effective tool for improving stool consistency in constipated patients. The trial was registered at ClinicalTrials.gov: NCT05980988.

Integrated InP frequency discriminator for Phase-modulated microwave photonic links.

We report the design, fabrication and characterization of an integrated frequency discriminator on InP technology for microwave photonic phase modulated links. The optical chip is, to the best of our knowledge, the first reported in an active platform and the first to include the optical detectors. The discriminator, designed as a linear filter in intensity, features preliminary SFDR values the range between 67 and 79 dB.Hz(2/3) for signal frequencies in the range of 5-9 GHz limited, in principle, by the high value of the optical losses arising from the use of several free space coupling devices in our experimental setup. As discussed, these losses can be readily reduced by the use of integrated spot-size converters improving the SFDR by 17.3 dB (84-96 dB.Hz(2/3)). Further increase up to a range of (104-116 dB.Hz(2/3)) is possible by reducing the system noise eliminating the EDFA employed in the setup and using a commercially available laser source providing higher output power and lower relative intensity noise. Other paths for improvement requiring a filter redesign to be linear in the optical field are also discussed.

Predictive value of the response to inhaled adenosine 5'-monophosphate for reducing the dose of inhaled corticosteroids in asthma.

BACKGROUND: Guidelines recommend stepping down inhaled corticosteroids (ICS) in patients with well-controlled asthma. However, no information is available on the index that should be used to predict the outcome of reducing the ICS dose. OBJECTIVE: The aim of this study was to investigate the degree of airway responsiveness to adenosine 5' monophosphate (AMP) as an index for deciding whether to reduce ICS dose. PATIENTS AND METHODS: The study population comprised 70 patients with asthma that was well controlled with ICS. Patients were treated for a 2-week baseline period with their usual dose of ICS. For the following 12 weeks, patients were treated with ICS at half their previous dose. Bronchial challenge with AMP was performed at the end of the baseline period and after 2 weeks of treatment with a reduced dose of ICS. Concentration-response curves were used to show the provocative concentration of AMP causing a 20% fall (PC20) in forced expiratory volume in 1 second (FEV1). RESULTS: A decrease in the PC20 of AMP of at least 1 doubling concentration 2 weeks after reducing the ICS dose was a significant predictor of the failure of dose reduction (P = .0011). In contrast, increased responsiveness to inhaled AMP at baseline did not predict the failure of dose reduction. CONCLUSIONS: Our results suggest that, in patients whose asthma is well controlled with ICS, measurement of the modification in the response to AMP 2 weeks after the dose of ICS was halved is a suitable method for assessing the risk of asthma exacerbation following a reduction in ICS dose.

Heart Failure and Major Adverse Cardiovascular Events in Atrial Fibrillation Patients: A Retrospective Primary Care Cohort Study.

BACKGROUND: Atrial fibrillation (AF) is a common cardiac arrhythmia that is associated with an increased risk of major adverse cardiovascular events (MACE). The main goal was to analyze the links and associations between AF and MACE. METHODS: A multicenter, observational, retrospective, community-based study of a cohort (n = 40,297) of the general population aged 65-95 years between 1 January 2015 and 31 December 2021 without a previous diagnosis of AF or MACE in the Primary Care setting. RESULTS: 2574 people (6.39%) developed a first AF event, resulting in an overall incidence of 8.9/1000 people-years [CI95% 8.6-9.2]. The incidence of MACE among those with AF was 75.1/1000 people-years [CI95% 70.8-79.5], whereas among those without AF, it was 20.6/1000 people-years [CI 95% 20.2-21.1], resulting in a rate ratio of 3.65 [CI 95% 3.43-3.88, p < 0.001]. Besides, the incidence of HF with AF was 40.1 people-years [CI 95% 37.1-43.2], while in the group without AF, it was 8.3 people-years [CI 95% 7.9-8.6, p < 0.001], with a rate ratio of 4.85 [CI 95% 4.45-55.3, p < 0.001]. Before an AF diagnosis, there is already a higher risk of chronic kidney disease, ischemic cardiopathy, and peripheral artery disease. A higher risk of poor nutritional status was detected among those with MACE (49.7% vs. 26.6%, p < 0.001). CONCLUSIONS: AF diagnosis increases the incidence of heart failure fourfold. Additional information is required to establish the connection between AF, major adverse cardiovascular events, and nutritional status.

Influence of velocity effects on the shape of N2 (and air) broadened H2O lines revisited with classical molecular dynamics simulations.

The modeling of the shape of H(2)O lines perturbed by N(2) (and air) using the Keilson-Storer (KS) kernel for collision-induced velocity changes is revisited with classical molecular dynamics simulations (CMDS). The latter have been performed for a large number of molecules starting from intermolecular-potential surfaces. Contrary to the assumption made in a previous study [H. Tran, D. Bermejo, J.-L. Domenech, P. Joubert, R. R. Gamache, and J.-M. Hartmann, J. Quant. Spectrosc. Radiat. Transf. 108, 126 (2007)], the results of these CMDS show that the velocity-orientation and -modulus changes statistically occur at the same time scale. This validates the use of a single memory parameter in the Keilson-Storer kernel to describe both the velocity-orientation and -modulus changes. The CMDS results also show that velocity- and rotational state-changing collisions are statistically partially correlated. A partially correlated speed-dependent Keilson-Storer model has thus been used to describe the line-shape. For this, the velocity changes KS kernel parameters have been directly determined from CMDS, while the speed-dependent broadening and shifting coefficients have been calculated with a semi-classical approach. Comparisons between calculated spectra and measurements of several lines of H(2)O broadened by N(2) (and air) in the ν(3) and 2ν(1) + ν(2) + ν(3) bands for a wide range of pressure show very satisfactory agreement. The evolution of non-Voigt effects from Doppler to collisional regimes is also presented and discussed.

Transdermal delivery of alprazolam from a monolithic patch: formulation based on in vitro characterization.

Alprazolam, a benzodiazepine widely used for the treatment of psychiatric disorders, has been aimed to be formulated in a transdermal delivery system (TDS) prototype. A series of TDS prototypes dosed in all cases at 0.35 mg·cm(-2) of alprazolam were prepared as a monolithic drug in adhesive matrix using acrylic pressure-sensitive adhesives (PSA) of acrylate vinyl acetate (Duro-tack(®)). The effects of several permeation enhancers as azone, transcutol, propylene glycol, dodecyl alcohol, decyl alcohol, diethanolamine, N-methyl pyrrolidone and lauric acid were studied. Prototypes have been characterized based on adhesion parameters (peel adhesion and shear adhesion), in vitro human skin permeation and in vitro drug release according to European Pharmacopoeia for the selected prototype. Best results show that a combination of permeation enhancers from different chemical groups is able to provide almost a 33 fold increase in the transdermal alprazolam flux of an aqueous saturated dispersion (from 0.054 ± 0.019 to 1.76 ± 0.21 µg h.cm(-2)). Based on these in vitro flux data, a predictive simulation of the achievable plasmatic levels was performed assuming a constant systemic infusion of drug. In summary, it is possible to obtain a prototype of a TDS of alprazolam with adequate adhesive properties (peel adhesion and shear adhesion) and able to predict sustained therapeutic plasmatic levels.

All silicon waveguide spherical microcavity coupler device.

A coupler based on silicon spherical microcavities coupled to silicon waveguides for telecom wavelengths is presented. The light scattered by the microcavity is detected and analyzed as a function of the wavelength. The transmittance signal through the waveguide is strongly attenuated (up to 25 dB) at wavelengths corresponding to the Mie resonances of the microcavity. The coupling between the microcavity and the waveguide is experimentally demonstrated and theoretically modeled with the help of FDTD calculations.

Transmission and group-delay characterization of coupled resonator optical waveguides apodized through the longitudinal offset technique.

In this Letter, the amplitude and group delay characteristics of coupled resonator optical waveguides apodized through the longitudinal offset technique are presented. The devices have been fabricated in silicon-on-insulator technology employing deep ultraviolet lithography. The structures analyzed consisted of three racetracks resonators uniform (nonapodized) and apodized with the aforementioned technique, showing a delay of 5 ± 3 ps and 4 ± 0.5 ps over 1.6 and 1.4 nm bandwidths, respectively.

Communication: observation of homonuclear propensity in collisional relaxation of the 13C12CD2 (v2=1) isotopologue of acetylene by stimulated Raman spectroscopy.

We report the first experimental observation of homonuclear propensity in collisional relaxation of a polyatomic molecule. A pump-probe stimulated Raman setup is used to pump population to a single rotational level of the v(2) = 1 vibrationally excited state in (13)C(12)CD(2) and then monitor the redistribution of the rotational population that has taken place after a fixed delay. The Q-branch of the 2ν(2)-ν(2) band shows a pattern of intensity alternation between the even and the odd rotational components, with the greater intensities always corresponding to the rotational levels with the same parity as the one where all the population was initially deposited. The effect can be explained by the existence of a propensity rule that favors collisional relaxation between rovibrational levels of the same parity.

Crystallization and preliminary X-ray analysis of D-2-hydroxyacid dehydrogenase from Haloferax mediterranei.

D-2-hydroxyacid dehydrogenase (D2-HDH) from Haloferax mediterranei has been overexpressed in Escherichia coli, solubilized in 8 M urea and refolded by rapid dilution. The protein was purified and crystallized by the hanging-drop vapour-diffusion method using ammonium sulfate or PEG 3350 as precipitant. Two crystal forms representing the free enzyme and the nonproductive ternary complex with alpha-ketohexanoic acid and NAD(+) grew under these conditions. Crystals of form I diffracted to beyond 3.0 A resolution and belonged to the monoclinic space group P2(1), with unit-cell parameters a = 66.0, b = 119.6, c = 86.2 A, beta = 96.3 degrees . Crystals of form II diffracted to beyond 2.0 A resolution and belonged to the triclinic space group P1, with unit-cell parameters a = 66.5, b = 75.2, c = 77.6 A, alpha = 109.1, beta = 107.5, gamma = 95.9 degrees. The calculated values for V(M) and analysis of the self-rotation and self-Patterson functions suggest that the asymmetric unit in both crystal forms contains two dimers related by pseudo-translational symmetry.

Experiences with vaccination in countries endemically infected with highly pathogenic avian influenza: the Food and Agriculture Organization perspective.

Vaccination has been used extensively for the control and prevention of highly pathogenic avian influenza (HPAI) caused by viruses of the H5N1 subtype in endemically infected countries. The Food and Agriculture Organization views vaccination as a legitimate aid in the control and prevention of infection and disease caused by HPAI viruses but does not see it as a panacea. Vaccination should be used as just one in a number of measures used together to reduce the effect and risk of infection. It will be required for a considerable time in endemically infected countries. The methods used in Vietnam in implementing blanket vaccination against H5N1 HPAI viruses demonstrate the steps that should be considered when introducing vaccination. So far, it has not been possible to determine the precise effect of vaccination in endemically infected countries because it has been used in combination with other measures. Well managed vaccination campaigns will reduce the incidence of infection in poultry and therefore reduce the risk to humans from these viruses. Vaccination was implemented to protect both poultry and humans, with a major goal being to reduce the risk of emergence of a human influenza pandemic virus. Economic analysis of vaccination should focus on cost-effectiveness of proposed strategies. Ex-ante and ex-post evaluation of vaccination campaigns should take into account the benefits generated in the poultry sector and for human health.

[Scintigraphy of the intraperitoneal cavity using technetium 99m as a diagnostic technique for diaphragmatic leaks in peritoneal dialysis: regarding two cases]. / La gammagrafía con Tc99m intraperitoneal como técnica diagnóstica de fugas diafragmáticas en pacientes en diálisis peritoneal: a propósito de dos casos.

Pleural effusion secondary to pleuroperitoneal communication is an unusual complication of continuous ambulatory peritoneal dialysis. Many modalities have been used to diagnosis pleuroperitoneal: pleural fluid analysis, chest X- ray, Tc-99m gammagraphy, computed tomography scan and magnetic resonance image. Some of these procedures are invasive or have a high risk of induced-contrast nephrotoxicity. We present two case reports of pleuroperitoneal leak in two patients on peritoneal dialysis diagnosed with Tc-99m gammagraphy. We conclude that Tc- 99m gammagraphy is a simple, safe, non invasive, low radiation exposure and cost effective method in the assessment and evaluation of complications related to peritoneal dialysis such as pleuroperitoneal leak.