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We present an isotropic ab initio (para-H2)4 four-body interaction potential energy surface (PES). The electronic structure calculations are performed at the correlated coupled-cluster theory level, with single, double, and perturbative triple excitations. They use an atom-centered augmented correlation-consistent double zeta basis set, supplemented by a (3s3p2d) midbond function. We use a multilayer perceptron to construct the PES. We apply a rescaling transformation to the output energies during training to improve the prediction of weaker energies in the sample data. At long distances, the interaction energies are adjusted to match the empirically derived four-body dispersion interaction. The four-body interaction energy at short intermolecular separations is net repulsive. The use of this four-body PES, in combination with a first principles pair potential for para-H2 [J. Chem. Phys. 119, 12551 (2015)] and an isotropic ab initio three-body potential for para-H2 [J. Chem. Phys. 156, 044301 (2022)], is expected to provide closer agreement with experimental results.
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BACKGROUND: Child mortality is high in Ethiopia, but reliable data on the causes of death are scarce. We aimed to gather data for the contributory causes of stillbirth and child deaths in eastern Ethiopia. METHODS: In this population-based post-mortem study, we established a death-notification system in health facilities and in the community in Kersa (rural), Haramaya (rural) and Harar (urban) in eastern Ethiopia, at a new site of the Child Health and Mortality Prevention Surveillance (CHAMPS) network. We collected ante-mortem data, did verbal autopsies, and collected post-mortem samples via minimally invasive tissue sampling from stillbirths (weighing at least 1000 g or with an estimated gestational age of at least 28 weeks) and children who died younger than 5 years. Children-or their mothers, in the case of stillbirths and deaths in children younger than 6 months-had to have lived in the catchment area for the past 6 months to be included. Molecular, microbiological, and histopathological analyses were done in collected samples. Cause of death was established by an expert panel on the basis of these data and classified as underlying, comorbid, or immediate separately for stillbirths, neonatal deaths (deaths aged 0-27 days), and child deaths (aged 28 days to <5 years). FINDINGS: Between Feb 4, 2019, and Feb 3, 2021, 312 deaths were eligible for inclusion, and the families gave consent in 195 (63%) cases. Cause of death was established in 193 (99%) cases. Among 114 stillbirths, the underlying cause of death was perinatal asphyxia or hypoxia in 60 (53%) and birth defects in 24 (21%). Among 59 neonatal deaths, the most common underlying cause was perinatal asphyxia or hypoxia (17 [29%]) and the most common immediate cause of death was neonatal sepsis, which occurred in 27 (60%). Among 20 deaths in children aged 28 days to 59 months, malnutrition was the leading underlying cause (15 [75%]) and infections were common immediate and comorbid causes. Pathogens were identified in 19 (95%) child deaths, most commonly Klebsiella pneumoniae and Streptococcus pneumoniae. INTERPRETATION: Perinatal asphyxia or hypoxia, infections, and birth defects accounted for most stillbirths and child deaths. Most deaths could have been prevented with feasible interventions, such as improved maternity services, folate supplementation, and improved vaccine uptake. FUNDING: Bill & Melinda Gates Foundation.
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Muerte Perinatal , Mortinato , Recién Nacido , Niño , Humanos , Femenino , Embarazo , Mortinato/epidemiología , Autopsia , Etiopía/epidemiología , Asfixia , Causas de Muerte , Mortalidad InfantilRESUMEN
We present the equation of state of solid parahydrogen between 0.024 and 0.1 Å-3 at T = 4.2 K, calculated using path integral Monte Carlo simulations, with ab initio two-body and three-body interaction potentials. We correct for finite size simulation errors using potential tail corrections. Trotter factorization errors are accounted for either via extrapolation or by using a suitably small imaginary time step. We incorporate the three-body interaction using two methods: (1) the full inclusion method, where pair and three-body interactions are used in both Monte Carlo sampling and in the energy estimators, and (2) the perturbative method, where three-body interactions are omitted from sampling but are still present in energy estimations. Both treatments of the three-body interaction return very similar total energies and pressures. The presence of three-body interactions has only minor effects on the structural properties of the solid. Whereas the pair interaction, on its own, significantly overestimates the pressure of solid parahydrogen, the additional presence of the three-body interaction causes a severe underestimation of the pressure. Our findings suggest that accurate simulations of solid parahydrogen require four-body and possibly higher-order many-body interactions. It may also be the case that static interaction potentials are entirely unsuitable for simulations of solid parahydrogen at high densities.
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We present a 3D isotropic ab initio three-body (para-H2)3 interaction potential energy surface (PES). The electronic structure calculations are carried out at the correlated coupled-cluster theory level, with single, double, and perturbative triple excitations. The calculations use an augmented correlation-consistent triple zeta basis set and a supplementary midbond function. We construct the PES using the reproducing-kernel Hilbert space toolkit [O. T. Unke and M. Meuwly, J. Chem. Inf. Model. 57, 1923 (2017)] with phenomenological and empirical adjustments to account for short-range and long-range behaviors. The (para-H2)3 interaction energies deviate drastically from the Axilrod-Teller-Muto (ATM) potential at short intermolecular separations. We find that the configuration of three para-H2 molecules at the corners of an equilateral triangle is responsible for the majority of the (para-H2)3 interaction energy contribution in a hexagonal-close-packed lattice. In cases where two para-H2 molecules are close to one another while the third is far away, the (para-H2)3 interaction PES takes the form of a modified version of the ATM potential. We expect the combination of this PES together with a first-principles para-H2-para-H2 adiabatic hindered rotor potential to outperform a widely used effective pair potential for condensed many-body systems of para-H2.
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Cow's milk protein intolerance (CMPI) is a common condition that causes gastrointestinal bleeding in the first year of life. It is the most common cause of chronic blood loss and anemia; however, severe massive hematemesis is an uncommon condition. Herein, we present a case of severe massive hematemesis with melena stool in a six-month-old boy with cow's milk protein intolerance. In this case, we described management used in poor developing countries.
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BACKGROUND: Chylomicron retention disease (Anderson disease) is a result for variant of the SAR1B gene. It is a rare autosomal recessive hereditary disorder with most incidence in infant. It is characterized by lipid malabsorption syndrome with fatty, chronic diarrhea, and growth retardation. CASE PRESENTATION: We report a case of a 19-month Syrian boy who presented with vomiting, growth failure, and chronic, fatty diarrhea. Upper gastrointestinal endoscopy showed whitish appearing duodenal mucosa and small intestinal biopsies revealed steatosis of enterocytes. Genetic testing confirmed chylomicron retention disease with the first description of variant located in the fourth helix of sar1b protein. The patient is treated with nutritional supplements and fat-soluble vitamin supplementation resulting in significant improvement. CONCLUSION: Early endoscopy is recommended in infants with persistent vomiting and failure to thrive due to high suspicion for a disorder of hypocholesterolemia. Early diagnosis and treatment are essential to avoid serious clinical complications, especially neurological impairment.
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Hipobetalipoproteinemias , Síndromes de Malabsorción , Proteínas de Unión al GTP Monoméricas , Humanos , Lactante , Síndromes de Malabsorción/diagnóstico , Síndromes de Malabsorción/genética , Masculino , Proteínas de Unión al GTP Monoméricas/metabolismo , SiriaRESUMEN
BACKGROUND: The current burden of >5 million deaths yearly is the focus of the Sustainable Development Goal (SDG) to end preventable deaths of newborns and children under 5 years old by 2030. To accelerate progression toward this goal, data are needed that accurately quantify the leading causes of death, so that interventions can target the common causes. By adding postmortem pathology and microbiology studies to other available data, the Child Health and Mortality Prevention Surveillance (CHAMPS) network provides comprehensive evaluations of conditions leading to death, in contrast to standard methods that rely on data from medical records and verbal autopsy and report only a single underlying condition. We analyzed CHAMPS data to characterize the value of considering multiple causes of death. METHODS AND FINDINGS: We examined deaths identified from December 2016 through November 2020 from 7 CHAMPS sites (in Bangladesh, Ethiopia, Kenya, Mali, Mozambique, Sierra Leone, and South Africa), including 741 neonatal, 278 infant, and 241 child <5 years deaths for which results from Determination of Cause of Death (DeCoDe) panels were complete. DeCoDe panelists included all conditions in the causal chain according to the ICD-10 guidelines and assessed if prevention or effective management of the condition would have prevented the death. We analyzed the distribution of all conditions listed as causal, including underlying, antecedent, and immediate causes of death. Among 1,232 deaths with an underlying condition determined, we found a range of 0 to 6 (mean 1.5, IQR 0 to 2) additional conditions in the causal chain leading to death. While pathology provides very helpful clues, we cannot always be certain that conditions identified led to death or occurred in an agonal stage of death. For neonates, preterm birth complications (most commonly respiratory distress syndrome) were the most common underlying condition (n = 282, 38%); among those with preterm birth complications, 256 (91%) had additional conditions in causal chains, including 184 (65%) with a different preterm birth complication, 128 (45%) with neonatal sepsis, 69 (24%) with lower respiratory infection (LRI), 60 (21%) with meningitis, and 25 (9%) with perinatal asphyxia/hypoxia. Of the 278 infant deaths, 212 (79%) had ≥1 additional cause of death (CoD) beyond the underlying cause. The 2 most common underlying conditions in infants were malnutrition and congenital birth defects; LRI and sepsis were the most common additional conditions in causal chains, each accounting for approximately half of deaths with either underlying condition. Of the 241 child deaths, 178 (75%) had ≥1 additional condition. Among 46 child deaths with malnutrition as the underlying condition, all had ≥1 other condition in the causal chain, most commonly sepsis, followed by LRI, malaria, and diarrheal disease. Including all positions in the causal chain for neonatal deaths resulted in 19-fold and 11-fold increases in attributable roles for meningitis and LRI, respectively. For infant deaths, the proportion caused by meningitis and sepsis increased by 16-fold and 11-fold, respectively; for child deaths, sepsis and LRI are increased 12-fold and 10-fold, respectively. While comprehensive CoD determinations were done for a substantial number of deaths, there is potential for bias regarding which deaths in surveillance areas underwent minimally invasive tissue sampling (MITS), potentially reducing representativeness of findings. CONCLUSIONS: Including conditions that appear anywhere in the causal chain, rather than considering underlying condition alone, markedly changed the proportion of deaths attributed to various diagnoses, especially LRI, sepsis, and meningitis. While CHAMPS methods cannot determine when 2 conditions cause death independently or may be synergistic, our findings suggest that considering the chain of events leading to death can better guide research and prevention priorities aimed at reducing child deaths.
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Causas de Muerte/tendencias , Salud Infantil/tendencias , Mortalidad del Niño/tendencias , Salud del Lactante/tendencias , Mortalidad Infantil/tendencias , África , Factores de Edad , Asia , Autopsia , Preescolar , Femenino , Carga Global de Enfermedades , Humanos , Lactante , Recién Nacido , Masculino , Vigilancia de la Población , Factores de RiesgoRESUMEN
Coeliac disease (CD) and cystic fibrosis (CF) are well known as the most common causes of chronic intestinal malabsorption in childhood. The coexistence of coeliac disease with cystic fibrosis is uncommon. Here, we describe the case of cystic fibrosis in a patient diagnosed with coeliac disease who failed to respond clinically to a gluten-free diet and had persistent steatorrhea and failure to thrive.
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Isoniazid (INH) is highly bactericidal against replicating tubercule bacilli and is involved in all antituberculous chemotherapeutic regimens. Several neurological adverse effects, following both therapeutic and overdose use of INH, have been reported in adults in the literature. Here, we present a case of a 5-year-old girl with intestinal Tuberculosis, who developed hemiclonic seizure as a side effect of INH therapeutic dose after 2 weeks of tuberculosis therapy.
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Muerte Materna , Muerte Perinatal , Calidad de la Atención de Salud , Adulto , Países en Desarrollo , Etiopía/epidemiología , Femenino , Humanos , Lactante , Recién Nacido , Muerte Materna/etiología , Muerte Materna/prevención & control , Mortalidad Materna , Evaluación de Resultado en la Atención de Salud , Muerte Perinatal/etiología , Muerte Perinatal/prevención & control , Mortalidad Perinatal , Política , EmbarazoRESUMEN
BACKGROUND AND STUDY AIMS: The recognition of suggestive endoscopic markers in the duodenum during open access endoscopy can help identifying patients who are likely to develop coeliac disease (CD). This study aims to determine the diagnostic accuracy of duodenal endoscopic markers for the diagnosis of CD. PATIENTS AND METHODS: All children (0-15 years) who underwent oesophagogastroduodenoscopy (EGD) for any reason suggestive of CD at the paediatric department of Al-Assad University Hospital in Latakia, Syria during a 4-year period (from January 2010 to December 2013) were retrospectively included, in the study; this yielded a consecutive cohort without selection bias. The relevant data were obtained from the patients' files. Four duodenal endoscopic markers, including scalloping, reduction of duodenal folds, nodular mucosal pattern, and scattered white spots, were evaluated. RESULTS: During the study period, 504 children underwent EGD of whom 123 (24.4%) were ultimately diagnosed with CD. At least one marker was observed in 200/504 children (39.6%) and the diagnostic values were as follows: Sensitivity (91%), specificity (76%), positive predictive value (56%), and negative predictive value (97%). Scalloping had the highest sensitivity and specificity of 89% and 96%, respectively. CONCLUSION: Careful examination of the second and third parts of the duodenum during endoscopy can be helpful in identifying CD. Scalloping is the most common endoscopic marker, and the high NPV values of endoscopic markers should be interpreted cautiously, as the diagnosis of CD can be missed.
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Enfermedad Celíaca/diagnóstico , Duodeno/patología , Endoscopía del Sistema Digestivo , Adolescente , Niño , Preescolar , Femenino , Humanos , Lactante , Mucosa Intestinal/patología , Masculino , Estudios Retrospectivos , Sensibilidad y Especificidad , SiriaRESUMEN
Gastric duplication cysts (GDCs) are rare congenital anomalies. Presentation of GDCs varies from an asymptomatic abdominal mass to fulminant or massive gastrointestinal (GI) bleeding. Herein, we describe a case of a GDC in a 10-month-old infant presenting with unexplained massive GI hemorrhage and hematemesis. An abdominal ultrasound was negative, while computerized tomography was, initially, inaccessible. Through a series of repeated esophagogastroduodenoscopies, we documented penetration of the GDC into the gastric cavity that was later confirmed by computerized tomography. The patient was treated successfully with surgical resection.
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We generate the equation of state (EOS) of solid parahydrogen (para-H2) using a path-integral Monte Carlo (PIMC) simulation based on a highly accurate first-principles adiabatic hindered rotor potential energy curve for the para-H2 dimer. The EOS curves for the fcc and hcp structures of solid para-H2 near the equilibrium density show that the hcp structure is the more stable of the two, in agreement with experiment. To accurately reproduce the structural and energy properties of solid para-H2, we eliminated by extrapolation the systematic errors associated with the choice of simulation parameters used in the PIMC calculation. We also investigate the temperature dependence of the EOS curves, and the invariance of the equilibrium density with temperature is satisfyingly reproduced. The pressure as a function of density and the compressibility as a function of pressure are both calculated using the obtained EOS and are compared with previous simulation results and experiments. We also report the first ever a priori prediction of a vibrational matrix shift from first-principles two-body potential functions, and its result for the equilibrium state agrees well with experiment.
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The development of bone was a major step in the evolution of vertebrates. A bony skeleton provided structural support and a calcium reservoir essential for the movement from an aquatic to a terrestrial environment. Cartilaginous fishes are the oldest living group of jawed vertebrates. In this study we have identified three members of the parathyroid hormone (Pth) gene family in a cartilaginous fish, the elephant shark (Callorhinchus milii). The three genes include two Pth genes, designated as Pth1 and Pth2, and a Pthrp gene. Phylogenetic analysis suggested that elephant shark Pth2 is an ancient gene whose orthologue is lost in bony vertebrates. The Pth1 and Pth2 genes have the same structure as the Pth gene in bony vertebrates, whereas the structure of the Pthrp gene is more complex in tetrapods compared with elephant shark. The three elephant shark genes showed distinct patterns of expression, with Pth2 being expressed only in the brain and spleen. This contrasts with localization of the corresponding proteins, which showed considerable overlap in their distribution. There were conserved sites of localization for Pthrp between elephant shark and mammals, including tissues such as kidney, skin, skeletal and cardiac muscle, pancreas, and cartilage. The elephant shark Pth1(1-34) and Pthrp(1-34) peptides were able to stimulate cAMP accumulation in mammalian UMR106.01 cells. However, Pth2(1-34) peptide did not show such PTH-like biologic activity. The presence of Pth and Pthrp genes in the elephant shark indicates that these genes played fundamental roles before their recruitment to bone development in bony jawed vertebrates.