Validation of maternal recall on exclusive breastfeeding 12 months after childbirth.

OBJECTIVE: We aimed to assess the validity of maternal recall of exclusive breastfeeding (EBF) at 3 months obtained 12 months after childbirth. DESIGN: A population-based birth cohort study. The gold standard is maternal report of EBF at the age of 3 months (yes or no) and age of introduction of other foods in the infant's diet. EBF was considered when the mother reported that no liquid, semi-solid or solid food was introduced up to that moment. The variable to be validated was obtained at 12 months after childbirth when the mother was asked about the age of food introduction. The prevalence of EBF at 3 months, and sensitivity, specificity, positive (PPV) and negative predictive values (NPV), and accuracy of 12-month recall with 95 % CI were calculated. SETTING: Pelotas, Brazil. PARTICIPANTS: 3700 mothers of participants of the Pelotas 2004 Birth Cohort. RESULTS: The prevalence of EBF at 3 months was 27·8 % (95 % CI 26·4, 29·3) and 49·0 % (95 % CI 47·4, 50·6) according to gold standard and maternal recall, respectively. The sensitivity of maternal recall at 12 months was 98·3 % (95 % CI 97·4, 99·0), specificity 70·0 % (95 % CI 68·2, 71·7), PPV 55·8 % (95 % CI 53·4, 58·1), NPV 99·1 % (95 % CI 98·6, 99·5) and accuracy 77·9 % (95 % CI 76·6, 79·2). When the analyses were stratified by maternal and infant characteristics, the sensitivity remained around 98 %, and the specificity ranged from 64·4 to 81·8 %. CONCLUSIONS: EBF recalled at the end of the first year of infant's life is a valid measure to be used in epidemiological investigations.

Pyruvic acid as attenuator of water deficit in cotton plants varying the phenological stage.

The lack of water during crop growth causes damage to any production system, especially when it occurs during the initial establishment or beginning of the reproductive stage. Although cotton can be properly managed in regions with water limitation, its yield is affected at different levels according to the genetics of the cultivar adopted. Exogenous application of some organic components has shown a stress-mitigating effect and can be a valuable procedure to enhance the yield of water stress-sensitive cultivars. The objective of this work was to evaluate the benefits of exogenous application of pyruvic acid (100 µM) in cotton plants under water deficit varying the phenological stage of the crop. The experiment was conducted in a greenhouse, where the plants were grown in pots and subjected to seven days of water suspension, initiated individually in stages V2 and B1. Each pot contained two plants. The treatments adopted were: T1 - control, T2 - water suppression; and T3 - water suppression + pyruvate application. The design was randomized blocks in a factorial scheme (3 × 3) with three replicates. The reductions in gas exchange and growth of the cultivars BRS Seridó, CNPA 7MH and FM 966 were more significant in the reproductive stage, especially for FM 966, which was more sensitive. Pyruvate application reduced the effects of water suppression on boll production by 31% in BRS Seridó and 34% in CNPA 7MH and FM 966.

Mineral composition and production of guava under salt stress and salicylic acid.

The limitation in the quality of water sources for irrigation in the semi-arid region of northeastern Brazil is increasingly present, so it is necessary to use water with high concentrations of salts for agricultural production, which makes the use of elicitors essential to mitigate the harmful effects of salinity on plants. Given the above, the objective of this study was to evaluate the effects of foliar application of salicylic acid on the mineral composition and production of guava plants under salt stress conditions in the post-grafting phase. The experiment was carried out under greenhouse conditions, in a randomized block design, in a 2 × 4 factorial scheme, with two levels of electrical conductivity of irrigation water (0.6 and 3.2 dS m-1) and four concentrations of salicylic acid (0, 1.2, 2.4, and 3.6 mM), with three replicates. During the flowering stage of guava, N, P, and K contents accumulated in the leaves according to the following order of concentration: N > K > P. Foliar application of 1.2 mM of salicylic acid increases the leaf contents of N, P, and K in guava plants grown under irrigation with water of 0.6 dS m-1. Water salinity of 3.2 dS m-1 reduces the growth and production components of guava plants.

Calcium pyruvate in the attenuation of the water deficit on the agro-industrial quality of ratoon sugarcane.

Sugarcane is one of the largest agricultural commodities when considering the export volume and the number of jobs generated. Sugarcane production in the Brazilian Northeast region is generally low due to several factors, including the irregular rainfall distribution, which highlights the importance of studies aimed at mitigating the deleterious effects of water stress. In this scenario, this study aimed to evaluate calcium pyruvate as a water deficit attenuator on the agro-industrial quality of sugarcane in the second cycle of cultivation. The experiment was conducted out under greenhouse conditions of the Federal University of Campina Grande, where five sugarcane commercial genotypes tested (G1- RB863129, G2- RB92579, G3- RB962962, G4- RB021754, and G5- RB041443) and three irrigation management strategies (E1- full irrigation, E2- water deficit with application of 30 mM of calcium pyruvate, and E3- water deficit without calcium pyruvate application), distributed in randomized blocks in 5 × 3 factorial arrangement with three replications. The RB021754 genotype under water deficit and without foliar application of calcium pyruvate increased the fiber content (13.2%) and the sugarcane moist cake weight (143.5 g). The effects of water deficit in sugarcane genotypes are attenuated by the exogenous application of 30 mM of calcium pyruvate, with benefits on the polarized sucrose content, apparent sucrose content of the juice, soluble solids content, purity, corrected cane POL, total recoverable sugars, and stem mass in relation to plants under water deficit without calcium pyruvate application.

Experimental determination of k0 and Q0 values for 121Sb, 123Sb and 130Ba targets applying covariance analysis.

This work consists of an experimental determination of k0 and Q0 for 121Sb, 123Sb and 130Ba targets. Covariance analysis has been introduced to supply not only the overall uncertainties in these parameters but also their correlations. The irradiations were performed near the core of the IEA-R1 4.5 MW swimming-pool nuclear research reactor of the Nuclear and Energy Research Institute (IPEN-CNEN/SP), in São Paulo, Brazil. The epithermal neutron flux shape parameter, alpha, at the irradiation position is very close to zero, which favors to obtain Q0 values more accurately. Two irradiations were carried out in sequence, using two sets of samples: the first with bare samples and the second inside a Cd cover. The activity measurements were carried out in a previously calibrated HPGe gamma-ray spectrometer. The measurements were corrected for: saturation, decay time, cascade summing, geometry, self-attenuation, measuring time and mass. Standard sources of 152Eu, 133Ba, 60Co and 137Cs traceable to a 4πß-γ primary system were used to obtain the HPGe gamma-ray peak efficiency as a function of the energy. The experimental efficiency curve was performed by a fourth-degree polynomial fit, in the energy range of the standard sources, 121-1408 keV, it contains all correlations between points. For energies above 1408 keV, the efficiencies were obtained by the Monte Carlo Method. The covariance matrix methodology was applied to all uncertainties involved. The final values for k0 and Q0 were compared with the literature.

Data analysis software package for radionuclide standardization with a digital coincidence counting system.

The Nuclear Metrology Laboratory (LMN) - IPEN, São Paulo, Brazil - developed a Digital Coincidence System (DCS), based on the Coincidence Counting Methodology, in order to improve its capabilities in radionuclide primary-standardization. Digital process is implemented in two steps: data-acquisition (a set of measurements) and offline software data-analysis and calculation. The present work shows the basics of the data-acquisition unit (Software Coincidence System - SCS), describes the DCS' data-analysis process and the initial approaches chosen for the implementation of the software package (Coincidence Analyzing Task - CAT). 152Eu standardization, performed for DCS testing, software expansion and validation, is briefly discussed.

Primary standardization and determination of gamma ray emission intensities of Ho-166.

The procedure followed by the Nuclear Metrology Laboratory (LMN) at the IPEN-CNEN/SP, in São Paulo, for the primary standardization of 166Ho is described. The activity of 166Ho was determined by the efficiency extrapolation technique applied to a 4πß(PC)-γ coincidence system using a gas flow proportional counter in 4π geometry coupled to a 76 × 76 mm NaI(Tl) crystal. The results for the γ-rays intensities at 80.57 and 1379.45 keV were 0.0651(11) and 0.00904(11), respectively.

Consistency test of coincidence-summing calculation methods for extended sources.

An internal consistency test of the calculation of coincidence-summing correction factors FC for volume sources is presented. The test is based on exact equations relating the values of FC calculated for three ideal measurement configurations. The test is applied to a number of 33 sets of FC values sent by 21 teams. Most sets passed the test, but not the results obtained using the quasi-point source approximation; in the latter case the test qualitatively indicated the magnitude of the bias of FC.

Determination of k0 and Q0 for 74Se, 113In, 186W and 191Ir targets applying covariance analysis.

In the present work, the determinations of k0 and Q0 for 74Se, 113In, 186W and 191Ir targets were performed. The irradiations were conducted near the core of the IEA-R1 4.5 MW swimming-pool nuclear research reactor of the Instituto de Pesquisas Energéticas e Nucleares (IPEN-CNEN/SP - Nuclear and Energy Research Institute), in São Paulo, Brazil. The irradiation position was chosen where the neutron spectrum shape parameter α is very close to zero. For this reason, the correction to be applied for the determination of Q0 is very close to one, thus improving the accuracy of the results. For each experiment, two irradiations were carried out in sequence: the first one with bare samples and the second with a cadmium cover around the samples. All partial uncertainties were considered, applying the covariance matrix methodology. The final results were compared with the literature.

Optimization of a coincidence system using plastic scintillators in 4pi geometry.

Improvements recently developed at the Nuclear Metrology Laboratory of IPEN-CNEN/SP in São Paulo were performed in order to increase the detector efficiency of a 4pibeta-gamma coincidence primary system using plastic scintillators in 4pi geometry. Measurements were undertaken and compared to the original system and Monte Carlo simulations of the extrapolation curves were calculated for this new system and compared to experimental results. For this purpose, the code Penelope was applied for calculating response functions for each detector and the code Esquema, developed at LMN, was used for simulating the decay scheme processes.

Standardization of (55)Fe by tracing method.

This work describes the procedure followed by the Laboratório de Metrologia Nuclear (LMN) for the standardization of (55)Fe by the tracing method. This technique was applied using two radionuclides, which decay by the electron capture process followed by a prompt gamma-ray, namely (51)Cr and (54)Mn, as tracers. The calibration was performed in a 4pibeta-gamma coincidence system. The efficiency was obtained by selecting a gamma-ray window set at the 320keV total absorption peak for (51)Cr and at 834keV for (54)Mn.

An intercomparison of Monte Carlo codes used in gamma-ray spectrometry.

In an intercomparison exercise, the Monte Carlo codes most commonly used in gamma-ray spectrometry today were compared with each other in order to gauge the differences between them in terms of typical applications. No reference was made to experimental data; instead, the aim was to confront the codes with each other, as they were applied to the calculation of full-energy-peak and total efficiencies. Surprising differences between the results of different codes were revealed.

Disintegration rate and gamma-ray emission probability per decay measurement of Cu-64.

The procedure followed by the Nuclear Metrology Laboratory (LMN) at the IPEN for the standardization of activity of 64Cu is described. The measurement was carried out in a 4π (PC) ß-γ coincidence system. The activity per unit mass of the solution was determined by the extrapolation technique. The events were registered using a Time to Amplitude Converter (TAC) associated with a Multi-channel Analyzer. The gamma-ray emission probability per decay of the 1345.7keV transition of 64Cu determined with a calibrated REGe gamma-ray spectrometer was (0.472 ± 0.010) %, in agreement with the literature.

SUMCOR: Cascade summing correction for volumetric sources applying MCNP6.

The main features of code SUMCOR developed for cascade summing correction for volumetric sources are described. MCNP6 is used to track histories starting from individual points inside the volumetric source, for each set of cascade transitions from the radionuclide. Total and FEP efficiencies are calculated for all gamma-rays and X-rays involved in the cascade. Cascade summing correction is based on the matrix formalism developed by Semkow et al. (1990). Results are presented applying the experimental data sent to the participants of two intercomparisons organized by the ICRM-GSWG and coordinated by Dr. Marie-Cristine Lépy from the Laboratoire National Henri Becquerel (LNE-LNHB), CEA, in 2008 and 2010, respectively and compared to the other participants in the intercomparisons.

Standardization of (59)Fe by 4π(PC)ß-γ software coincidence system.

The procedure for the standardization of (59)Fe using a 4π(PC)ß-γ software coincidence system is described. The standardization was performed with an experimental setup consisting of a thin window gas-flow proportional counter (PC) in 4π geometry coupled to a NaI(Tl) scintillator and to a HPGe detector. The data acquisition was carried out by means of a Software Coincidence System (SCS). The beta efficiency was changed by using Collodion films and aluminum foils as external absorbers.

Double vision in a child.

A 10-year-old boy presented with a complete left oculomotor cranial nerve palsy. Diagnostic evaluation, including neuroimaging and cerebral angiography revealed a small intracranial aneurysm compressing the third nerve. Neurosurgical clipping of the aneurysm produced resolution of the third nerve palsy. The rarity of this presentation in a young patient is discussed, along with the importance of rapid diagnosis and treatment.

Juvenile intervertebral disc calcification: recognition, management, and pathogenesis.

Juvenile intervertebral disc calcification is an uncommon disorder of childhood, characterized by calcification of the nucleus pulposus of one or more intervertebral discs. Calcification may remain dormant or subsequently become symptomatic. The symptoms include fever, malaise, and neck pain and are associated with an elevated erythrocyte sedimentation rate and, occasionally, leukocytosis. Although disc protrusion occurs in 38% of patients, neurological signs are distinctly uncommon. We report the case of a patient with a herniated T2-T3 calcified intervertebral disc and compressive myelopathy. Juvenile intervertebral disc calcification is generally a self-limiting disease that seldom requires an operation. The symptoms are transient, and resorption of the disc calcification is the rule once symptoms occur. Neither the cause of the disc calcification nor the trigger for the onset of symptoms is known. An inflammatory response within the disc appears to give rise to clinical symptoms and is associated with eventual resorption of the disc calcification.

Intracranial hemorrhage from aneurysms and arteriovenous malformations during pregnancy and the puerperium.

Intracranial hemorrhage (ICH) from an intracranial aneurysm or arteriovenous malformation is a grave complication of pregnancy and is responsible for 5 to 12% of all maternal deaths. We critically analyzed 154 cases of verified ICH during pregnancy from an identified intracranial lesion, including 2 patients treated at our institution and 152 cases previously reported in the literature in English. Aneurysms were responsible for ICH in 77% of patients, and arteriovenous malformations in 23%. Hemorrhage occurred antepartum in 92% of patients and postpartum in 8%. Women with angiomatous hemorrhage were younger than those with aneurysmal hemorrhage; however, in contrast to previous reports, we found no differences between angiomatous and aneurysmal hemorrhage with respect to parity or gestational age at the time of the initial hemorrhage. Hypertension and/or albuminuria were present at some time during the pregnancy in 34% of patients with documentation, which sometimes made it difficult to differentiate angiomatous or aneurysmal ICH from that associated with eclampsia. In a logistic regression analysis, surgical management of aneurysms, but not arteriovenous malformations, was associated with significantly lower maternal and fetal mortality, independent of other covariants. For those patients with a lesion not operated on, cesarean delivery afforded no better maternal or fetal outcome than did vaginal delivery. We conclude that the decision to operate after ICH during pregnancy should be based upon neurosurgical principles, whereas the method of delivery should be based upon obstetrical considerations. The perioperative and anesthetic management of the pregnant patient with a neurosurgical complication is discussed.

Cervical myelomeningoceles.

Cervical myelomeningoceles are rare dysraphic lesions. Nine cases of cervical myelomeningoceles are reported. The external features of all nine myelomeningoceles were strikingly similar: They were sturdy, tubular protuberances from the back of the infants' necks, covered at the base by full-thickness skin and covered on the dome by thick squamous epithelium. Internally, these were tethered cord lesions in which fibroneural bands or sagittal midline fibrous septa were tightly tethering the cervical spinal cord to the adjacent dural or intrasaccular soft tissues. Six of our early cases (Group 1) were initially treated with simple subcutaneous resection of the sac and ligation of the dural fistula without release of the internal tethering structures. Five of these children subsequently deteriorated 13 months to 8 years later, all with worsening hand function and spastic legs. All five were reexplored, and the tethering bands and septa were excised; all showed improvement. The other three neonates (Group 2) treated in the last 4 years underwent initial intradural exploration of the lesions; in one case, the tethering fibrous elements were only partially eliminated and the patient deteriorated 4 years later, but improved after a second operation for resection of a missed ventral fibrous septum. The other two Group 2 infants had a thorough release of the fibroneural stalks initially, and both were neurologically stable 3 years later. We recommend that cervical myelomeningoceles should be studied preoperatively with magnetic resonance imaging and computed tomographic myelography to identify the internal structures. The minimum initial surgical treatment should be a two-level laminectomy, intradural exploration, and excision of all tethering bands and septa, in addition to resection of the sac. If a split cord is revealed by imaging studies, both the ventral and dorsal surfaces of the hemicords must be carefully inspected to locate the median septum.

Split cord malformation: Part I: A unified theory of embryogenesis for double spinal cord malformations.

Much confusion still exists concerning the pathological definitions and clinical significance of double spinal cord malformations. Traditional terms used to describe the two main forms of these rare malformations, diastematomyelia and diplomyelia, add to the confusion by their inconsistent usage, ambiguities, and implications of their dissimilar embryogenesis. Based on the detailed radiographic and surgical findings of 39 cases of double cord malformations and the autopsy data on two other cases, this study endorses a new classification for double cord malformations and proposes a unified theory of embryogenesis for all their variant forms and features. The new classification recommends the term split cord malformation (SCM) for all double spinal cords. A Type I SCM consists of two hemicords, each contained within its own dural tube and separated by a dura-sheathed rigid osseocartilaginous median septum. A Type II SCM consists of two hemicords housed in a single dural tube separated by a nonrigid, fibrous median septum. These two essential features necessary for typing, the state of the dural tube and the nature of the median septum, do not ever overlap between the two main forms and can always be demonstrated by imaging studies so that accurate preoperative typing is always possible. All other associated structures in SCM such as paramedian nerve roots, myelomeningoceles manqué, and centromedian vascular structures frequently do overlap between types and are not reliable typing criteria. The unified theory of embryogenesis proposes that all variant types of SCMs have a common embryogenetic mechanism. Basic to this mechanism is the formation of adhesions between ecto- and endoderm, leading to an accessory neurenteric canal around which condenses an endomesenchymal tract that bisects the developing notochord and causes formation of two hemineural plates. The altered state of the emerging split neural tube and the subsequent ontogenetic fates of the constituent components of the endomesenchymal tract ultimately determine the configuration and orientation of the hemicords, the nature of the median septum, the coexistence of various vascular, lipomatous, neural, and fibrous oddities within the median cleft, the high association with open myelodysplastic and cutaneous lesions, and the seemingly unlikely relationship with fore and midgut anomalies. The multiple facets of this theory are presented in increasing complexity against the background of known embryological facts and theories; the validity of each facet is tested by comparing structures and phenomena predicted by the facet with actual radiographic, surgical, and histopathological findings of these 41 cases of SCM.