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Bacterial cellulose (BC) represents a promising biomaterial, due to its unique and versatile properties. We report, herein, on purposely-designed structural modifications of BC that enhance its application as a wound dressing material. Chemical modification of the functional groups of BC was performed initially to introduce a hydrophobic/oleophilic character to its surface. Specifically, silanization was carried out in an aqueous medium using methyltrimethoxisilane (MTMS) as the silanizing agent, and aerogels were subsequently prepared by freeze-drying. The BC-MTMS aerogel obtained displayed a highly porous (99 %) and lightweight structure with an oil absorption capacity of up to 52 times its dry weight. The XRD pattern indicated that the characteristic crystallographic planes of the native BC were maintained after the silanization process. Thermal analysis showed that the thermal stability of the BC-MTMS aerogel increased, as compared to the pure BC aerogel (pBC). Moreover, the BC-MTMS aerogel was not cytotoxic to fibroblasts and keratinocytes. In the second step of the study, the incorporation of natural oils into the aerogel's matrix was found to endow antimicrobial and/or healing properties to BC-MTMS. Bourbon geranium (Pelargonium X ssp.) essential oil (GEO) was the only oil that exhibited antimicrobial activity against the tested microorganisms, whereas buriti (Mauritia flexuosa) vegetable oil (BVO) was non-cytotoxic to the cells. This study demonstrates that the characteristics of the BC structure can be modified, while preserving its intrinsic features, offering new possibilities for the development of BC-derived materials for specific applications in the biomedical field.

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OBJECTIVES: This study aimed to analyze, in the São Paulo state of Brazil, time trends in prevalence, neonatal mortality, and neonatal lethality of central nervous system congenital malformations (CNS-CM) between 2004 and 2015. METHODS: Population-based study of all live births with gestational age ≥22 weeks and/or birthweight ≥400 g from mothers living in São Paulo State, during 2004-2015. CNS-CM was defined by the presence of International Classification Disease 10th edition codes Q00-Q07 in the death and/or live birth certificates. CNS-CM was classified as isolated (only Q00-Q07 codes), and non-isolated (with congenital anomalies codes nonrelated to CNS-CM). CNS-CM associated neonatal death was defined as death between 0 and 27 days after birth in infants with CNS-CM. CNS-CM prevalence, neonatal mortality, and lethality rates were calculated, and their annual trends were analyzed by Prais-Winsten Model. The annual percent change (APC) with 95% confidence interval (95%CI) was obtained. RESULTS: 7,237,628 live births were included in the study and CNS-CM were reported in 7526 (0.1%). CNS-CM associated neonatal deaths occurred in 2935 (39.0%). Isolated CNS-CM and non-isolated CNS-CM were found respectively in 5475 and 2051 livebirths, with 1525 (28%) and 1410 (69%) neonatal deaths. CNS-CM prevalence and neonatal lethality were stationary, however neonatal mortality decreased (APC -1.66; 95%CI -3.09 to -0.21) during the study. For isolated CNS-CM, prevalence, neonatal mortality, and lethality decreased over the period. For non-isolated CNS-CM, the prevalence increased, neonatal mortality was stationary, and lethality decreased during the period. The median time of CNS-CM associated neonatal deaths was 18 h after birth. CONCLUSIONS: During a 12-year period in São Paulo State, Brazil, neonatal mortality of infants with CNS-CM in general and with isolated CNS-CM showed a decreasing pattern. Nevertheless CNS-CM mortality remained elevated, mostly in the first day after birth.

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Acute ischemic stroke is a sudden neurological event caused by brain ischemia. Patients with large vessel occlusion are at high risk of developing significant cerebral edema, which can lead to rapid neurological decline. The optimal timing for decompressive hemicraniectomy to prevent further brain damage is still uncertain. This study aimed to identify potential predictors of severe brain edema. The data indicate that specific cytokines may help identify patients with a higher risk of developing life-threatening brain swelling in the early phase post-stroke. The association between a positive biomarker and the outcome was calculated, and three biomarkers-S100B protein, MMP-9, and IL-10-were found to be significantly associated with malignant edema. A model was derived for early predicting malignant cerebral edema, including S100B protein and IL-1 beta. These findings suggest that molecular biomarkers related to the ischemic cascade may be a helpful way of predicting the development of malignant cerebral edema in ischemic stroke patients, potentially widening the time window for intervention and assisting in decision-making. In conclusion, this study provides insights into the molecular mechanisms of severe brain edema and highlights the potential use of biomarkers in predicting the course of ischemic stroke.

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Starch's crystalline structure and gelatinization temperature might facilitate or hinder its use. Ball milling has frequently been mentioned in the literature as a method for reducing starch size and as a more environmentally friendly way to change starch, such as by increasing surface area and reactivity, which has an impact on other starch properties. In this study, starch samples were milled for varying durations (1, 5, 10, 20, and 30 h) and at different starch-to-ball mass ratios (1:6 and 1:20). Microscopy and XRD revealed that prolonged milling resulted in effective fragmentation and a decrease in crystallinity of the starch granules. Increasing milling times resulted in an increase in amylose content. Rheology and thermal studies revealed that gelatinization temperatures dropped with milling duration and that viscosity and thixotropy were directly influenced. The samples milled for 10, 20, and 30 h at a ratio of 1:20 were the most fragmented and upon drying formed a transparent film at ambient temperature, because of the lower gelatinization temperature. Starch ball milling could lead to the use of this material in thermosensitive systems.

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Introduction: Premature birth, perinatal asphyxia, and infections are the main causes of neonatal death. Growth deviations at birth also affect neonatal survival according to week of gestation at birth, particularly in developing countries. The purpose of this study was to verify the association between inappropriate birth weight and neonatal death in term live births. Methods: This is an observational follow-up study with all term live births from 2004 to 2013 in Sao Paulo State, Brazil. Data were retrieved with the deterministic linkage of death and birth certificates. The definition of very small for gestational age (VSGA) and very large for gestational age (VLGA) used the 10th percentile of 37 weeks and the 90th percentile of 41 weeks + 6 days, respectively, based on the Intergrowth-21st. We measured the outcome in terms of time to death and the status of each subject (death or censorship) in the neonatal period (0-27 days). Survival functions were calculated using the Kaplan-Meier method stratified according to the adequacy of birth weight into three groups (normal, very small, or very large). We used multivariate Cox regression to adjust for proportional hazard ratios (HRs). Results: The neonatal death rate during the study period was 12.03/10,000 live births. We found 1.8% newborns with VSGA and 2.7% with VLGA. The adjusted analysis showed a significant increase in mortality risk for VSGA infants (HR = 4.25; 95% CI: 3.89-4.65), independent of sex, 1-min Apgar score, and five maternal factors. Discussion: The risk of neonatal death in full-term live births was approximately four times greater in those with birth weight restriction. The development of strategies to control the factors that determine fetal growth restriction through planned and structured prenatal care can substantially reduce the risk of neonatal death in full-term live births, especially in developing countries such as Brazil.

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The industrial residue of cashew apple juice processing (MRC) was evaluated as an alternative medium for bacterial cellulose (BC) production by Komagataeibacter xylinus ATCC 53582 and Komagataeibacter xylinus ARS B42. The synthetic Hestrin-Schramm medium (MHS) was used as a control for growing and BC production. First, BC production was assessed after 4, 6, 8, 10, and 12 days under static culture. After 12 days of cultivation, K. xylinus ATCC 53582 produced the highest BC titer in MHS (3.1 g·L-1) and MRC (3 g·L-1), while significant productivity was attained at 6 days of fermentation. To understand the effect of culture medium and fermentation time on the properties of the obtained films, BC produced at 4, 6, or 8 days were submitted to infrared spectroscopy with Fourier transform, thermogravimetry, mechanical tests, water absorption capacity, scanning electron microscopy, degree of polymerization and X-ray diffraction. The properties of BC synthesized in MRC were identical to those of BC from MHS, according to structural, physical, and thermal studies. MRC, on the other hand, allows the production of BC with a high water absorption capacity when compared to MHS. Despite the lower titer (0.88 g·L-1) achieved in MRC, the BC from K. xylinus ARS B42 presented a high thermal resistance and a remarkable absorption capacity (14664 %), suggesting that it might be used as a superabsorbent biomaterial.

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It is critically important for stakeholders with distinct foci of attention on healthcare to understand patient evolution in the presence of an established diagnosis or with a suspected diagnosis of various diseases, specially considering death as an outcome. To study the long-term mortality of patients at a cardiovascular referral hospital. Deterministic binding (selection of pairs of registers from the hospital electronic health records and the mortality records of São Paulo state) from 2002 to 2017 was performed. Studied variables were: age, sex, hospital treatment unit where the first visit occurred (Emergency Unit, Outpatient Unit, Hospital Admissions, Diagnostics Services), treatment type, elapsed time between the first visit and death, diagnosis at first and last visits and variables related to death. Statistical Methods: descriptive, survival (with Kaplan-Meier method), correspondence and competitive risks analyses; in case of nonoccurrence of death until the end of 2017, the patients were considered alive. Statistical significance was set at values of P < .05. Median age at the first visit to the Hospital was 51.9 years. Birth locations included 4496 cities, 17.33% in São Paulo, 0.41% in Rio de Janeiro, 0.40% in Osasco, 24.04% in other cities. Sex included females (46.7%), males (44.2%), not defined (6.3%), and other (2.8%). We observed an association between diseases in ICD-10 Chapter 16 (certain conditions originating in the perinatal period) and Chapter 17 (congenital malformations, deformations, and chromosomal abnormalities), both as diagnoses and underlying causes of death, as well as between neoplasms as diagnoses and as the underlying cause of death. In this sample, there was an association between admission diagnoses and underlying causes of death, such as neoplasms, cardiovascular diseases, and congenital heart malformations. Additionally, patients who underwent a cardiac intervention had a smaller less mortality rate than those who were not operated on. There were also differences in cardiovascular mortality between distinct treatment units of the hospital ((Emergency Unit, Outpatient Unit, Hospital Admissions, Diagnostic Services).

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Moderate and late preterm newborns comprise around 85% of live births < 37 weeks gestation. Data on their neonatal mortality in middle-income countries is limited. This study aims to analyze the temporal trend, causes and timing of neonatal mortality of infants with 320/7-366/7 weeks gestation without congenital anomalies from 2004-2015 in the population of São Paulo State, Brazil. A database was built by deterministic linkage of birth and death certificates. Causes of death were classified by ICD-10 codes. Among 7,317,611 live births in the period, there were 545,606 infants with 320/7-366/7 weeks gestation without congenital anomalies, and 5782 of them died between 0 and 27 days. The neonatal mortality rate decreased from 16.4 in 2004 to 7.6 per thousand live births in 2015 (7.47% annual decrease by Prais-Winsten model). Perinatal asphyxia, respiratory disorders and infections were responsible, respectively, for 14%, 27% and 44% of the 5782 deaths. Median time to death was 24, 53 and 168 h, respectively, for perinatal asphyxia, respiratory disorders, and infections. Bottlenecks in perinatal health care are probably associated with the results that indicate the need for policies to reduce preventable neonatal deaths of moderate and late preterm infants in the most developed state of Brazil.

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Studies have described the occurrence of nanoparticles (NPs) in aquatic ecosystems, with particular attention to the widely commercialized carbon nanotubes (CNTs). Their presence in the environment raises concerns, especially regarding their toxicity when co-occurring with other pollutants such as metals. In the present study, changes to the metabolic capacity, oxidative, and neurologic status were evaluated in the presence of carboxylated multi-walled CNTs and chromium (Cr(III)) using two of the most ecologically and economically relevant filter feeder organisms: the clam species Ruditapes decussatus and R. philippinarum. Results indicated that although Cr, either alone or in combination with CNTs, was found in a similar concentration level in both species, a species-specific Cr accumulation was observed, with higher values in R. decussatus in comparison with R. philippinarum. Inhibition of antioxidant defenses and neurotoxic effects were detected only in R. philippinarum. The interaction between contaminants seems to have no effect in terms of antioxidant enzyme activities and neuro status. Nevertheless, synergistic activation of responses to both contaminants may have altered the metabolic capacity of bivalves, particularly evident in R. decussatus. While both clams are tolerant to both contaminants (alone and together), they showed a relevant accumulation capacity, which may represent a possible contaminant transfer to humans.

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BACKGROUND: In high- and middle-income countries, mortality associated to congenital diaphragmatic hernia (CDH) is high and variable. In Brazil, data is scarce regarding the prevalence, mortality, and lethality of CDH. This study aimed to analyze, in São Paulo state of Brazil, the temporal trends of prevalence, neonatal mortality and lethality of CDH and identify the time to CDH-associated neonatal death. METHODS: Population-based study of all live births with gestational age ≥ 22 weeks, birthweight ≥400g, from mothers residing in São Paulo State, Brazil, during 2004-2015. CDH definition and its subgroups classification were based on ICD-10 codes reported in the death and/or live birth certificates. CDH-associated neonatal death was defined as death up to 27 days after birth of infants with CDH. CDH prevalence, neonatal mortality and lethality were calculated and their annual percent change (APC) with 95% confidence intervals (95%CI) was analyzed by Prais-Winsten. Kaplan-Meier estimator identified the time after birth that CDH-associated neonatal death occurred. RESULTS: CDH prevalence was 1.67 per 10,000 live births, with a significant increase throughout the period (APC 2.55; 95%CI 1.30 to 3.83). CDH neonatal mortality also increased over the time (APC 2.09; 95%CI 0.27 to 3.94), while the lethality was 78.78% and remained stationary. For isolated CDH, CDH associated to non-chromosomal anomalies and CDH associated to chromosomal anomalies the lethality was, respectively, 72.25%, 91.06% and 97.96%, during the study period. For CDH as a whole and for all subgroups, 50% of deaths occurred within the first day after birth. CONCLUSIONS: During a 12-year period in São Paulo State, Brazil, CDH prevalence and neonatal mortality showed a significant increase, while lethality remained stable, yet very high, compared to rates reported in high income countries.

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The topical use of imiquimod (IMQ), a non-specific immune response modifier, showed to be a promising therapeutic option for the early-stage treatment of some type of oral cancer, even when performed with a formulation (Aldara®) developed and approved for skin application. The aim of this work was the development of buccal formulations for the topical administration of IMQ with improved mucosal retention and reduced trans-mucosal permeation when compared to the reference formulation. Three different hydrogels based on carboxymethyl chitosan (CMChit), sodium alginate (A), and xanthan gum (X) in different combinations were prepared, and the loading of imiquimod was successfully performed by using a micellar formulation based on d-α-tocopheril polyethylene glycol 100 succinate (TPGS). Except for CMChit formulation, in all the other cases, the performance in vitro on the mucosa resulted comparable to the commercial formulation, despite the drug loading being 50-fold lower. Converting the gels in films did not modify the IMQ accumulated with respect to the correspondent gel formulation but produced as a positive effect a significant reduction in the amount permeated. Compared to the commercial formulation, this reduction was significant (p < 0.01) in the case of X film, resulting in an improvement of the retained/permeated ratio from 1 to 5.44. Mucoadhesion evaluation showed similar behavior when comparing the developed gels and the commercial formulation, and an excellent bioadhesion was observed for the films.

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The environmental damage caused by plastic packaging and the need to reduce pollution requires actions to substitute plastic materials for more sustainable and biodegradable materials. Starch, gelatin, and bacterial cellulose films are three potential biodegradable polymeric films for use in packaging. However, these materials need improvements in their physical, chemical, and mechanical properties to be used in packaging. In this work, these films were treated with cold plasma to evaluate the effects of treatment conditions on several physical, chemical, and mechanical properties. The dielectric barrier discharge plasma technology was applied with varying treatment times (0 to 20 min) and excitation frequencies (50 to 900 Hz) at 20 kV. The optimal excitation frequency for starch films (50 Hz) was different from the optimal frequency for gelatin and bacterial cellulose films (900 Hz), indicating a high dependency on the treatment in this variable that is often neglected. Plasma treatment improved the hydrophobicity, surface morphology, water resistance, and mechanical properties of all three films, with the advantage of not recurring to chemical or biological additives.

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The purpose of this study was to investigate tissue repair of excisional wounds in hyperglycemic animals treated with chitosan-alginate membranes (CAM) produced in the presence of glycerol. 8-week C57B1 male mice were divided into normoglycemic animals with a 0.9% saline solution topical treatment (CTSF); hyperglycemic animals with 0.9% saline solution topical treatment (DMSF) and hyperglycemic animals with glycerol-plasticized chitosan-alginate membrane topical treatment (DMCAM). On post-wound day three, the DMCAM group presented a lower number of leukocytes, mature mastocytes, a higher number of vessels (p < 0.05), and active mastocytes (p < 0.05) when compared to the CTSF and DMSF groups. There were no differences regarding the distribution, deposition, organization, and thickness of collagen fibers. On day 7 there were no differences in the analysis of fibroblasts, mastocytes, and TGF−ß1 and VEGF expressions among the groups. Regarding collagen fibers, the DMCAM group presented slight red-orange birefringence when compared to the CTSF and DMSF groups. On day 14 there was a slight concentration of thinner elastic fibers for the DMCAM group, with a greater reorganization of papillary skin and improved red-orange birefringence collagen fibers, as well as net-shaped orientation, similar to intact skin. In addition, improved elastic fiber organization distributed in the entire neo-dermis and a larger presence of elaunin fibers were observed, in a similar pattern found in the intact skin. The use of CAM in cutaneous lesions boosted tissue repair since there was a smaller number of inflammatory cells and mastocytes, and an improvement in collagen deposition and collagen fibers. These results demonstrate the high potential of plasticized chitosan-alginate membrane for skin wound dressing of hyperglycemic patients.

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OBJECTIVE: This article aimed to report a temporal series of respiratory distress syndrome (RDS)-associated neonatal mortality rates in preterm live births in São Paulo state, Brazil, and to identify social, maternal, and neonatal characteristics associated with these deaths. STUDY DESIGN: This is a population-based study of all live births with gestational age (GA) between 22 and 36 weeks, birth weight ≥400 g, without congenital anomalies from mothers living in São Paulo state during 2004 to 2015. RDS-associated neonatal mortality was defined as death up to 27 days after birth with ICD-10 codes P22.0 or P28.0. RDS-associated neonatal mortality rate (annual percent change [APC] with 95% confidence intervals [95% CIs]) was analyzed by Prais-Winsten. Kaplan-Meier estimator identified the time after birth that the RDS-associated neonatal death occurred. Poisson's regression model compared social maternal and neonatal characteristics between preterm live births that survived the neonatal period and those with RDS-associated neonatal deaths, with results expressed in incidence rate ratio and 95% CI. RESULTS: A total of 645,276 preterm live births were included in the study, of which 612,110 survived and 11,078 had RDS-associated neonatal deaths. RDS-associated neonatal mortality rate was 17.17 per thousand preterm live births, with a decreasing annual trend (APC: -6.50%; 95% CI: -9.11 to -3.82%). The median time of these deaths was 48 hours after birth. The following risk factors for RDS-associated neonatal death were identified: maternal schooling ≤7 years (1.18; 1.09-1.29), zero to three prenatal care visits (1.25; 1.18-1.32), multiple pregnancy (1.24; 1.16-1.33), vaginal delivery (1.29; 1.22-1.36), GA 22 to 27 weeks (106.35; 98.36-114.98), GA 28 to 31 weeks (20.12; 18.62-21.73), male sex (1.16; 1.10-1.22), and 5-minute Apgar scores of 0 to 3 (6.74; 6.08-7.47) and 4 to 6 (3.97; 3.72-4.23). CONCLUSION: During the study period, RDS-associated neonatal mortality rates showed significant reduction. The relationship between RDS-associated neonatal deaths and social, maternal, and neonatal factors suggests the need for perinatal strategies to reduce prematurity and to improve the initial management of preterm infants. KEY POINTS: · RDS is associated with preterm live births.. · Impact of RDS-associated neonatal mortality in middle-income countries is scarce.. · Qualified perinatal care can reduce RDS-associated neonatal mortality..

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BACKGROUND: Prematurity and respiratory distress syndrome (RDS) are strongly associated. RDS continues to be an important contributor to neonatal mortality in low- and middle-income countries. This study aimed to identify clusters of preterm live births and RDS-associated neonatal deaths, and their cooccurrence pattern in São Paulo State, Brazil, between 2004 and 2015.  METHODS: Population-based study of all live births with gestational age ≥ 22 weeks, birthweight ≥ 400 g, without congenital anomalies from mothers living in São Paulo State, Brazil, during 2004-2015. RDS-associated neonatal mortality was defined as deaths < 28 days with ICD-10 codes P22.0 or P28.0. RDS-associated neonatal mortality and preterm live births rates per municipality were submitted to first- and second-order spatial analysis before and after smoothing using local Bayes estimates. Spearman test was applied to identify the correlation pattern between both rates. RESULTS: Six hundred forty-five thousand two hundred seventy-six preterm live births and 11,078 RDS-associated neonatal deaths in São Paulo State, Brazil, during the study period were analyzed. After smoothing, a non-random spatial distribution of preterm live births rate (I = 0.78; p = 0.001) and RDS-associated neonatal mortality rate (I = 0.73; p = 0.001) was identified. LISA maps confirmed clusters for both, with a negative correlation (r = -0.24; p = 0.0000). Clusters of high RDS-associated neonatal mortality rates overlapping with clusters of low preterm live births rates were detected. CONCLUSIONS: Asymmetric cluster distribution of preterm live births and RDS-associated neonatal deaths may be helpful to indicate areas for perinatal healthcare improvement.

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There are several routes of drug administration, and each one has advantages and limitations. In the case of the topical application in the oral cavity, comprising the buccal, sublingual, palatal, and gingival regions, the advantage is that it is painless, non-invasive, allows easy application of the formulation, and it is capable of avoiding the need of drug swallowing by the patient, a matter of relevance for children and the elderly. Another advantage is the high permeability of the oral mucosa, which may deliver very high amounts of medication rapidly to the bloodstream without significant damage to the stomach. This route also allows the local treatment of lesions that affect the oral cavity, as an alternative to systemic approaches involving injection-based methods and oral medications that require drug swallowing. Thus, this drug delivery route has been arousing great interest in the pharmaceutical industry. This review aims to condense information on the types of biomaterials and polymers used for this functionality, as well as on production methods and market perspectives of this topical drug delivery route.

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BACKGROUND: Infant mortality rate is a measure of population health and neonatal mortality account for great proportion of these deaths. Underdevelopment might be associated to higher neonatal mortality risk due to assistant related factors. Spatial and temporal distribution of mortality help identifying and developing strategies for interventions. OBJECTIVE: To investigate the cluster areas of asphyxia-associated neonatal mortality and to explore its association with per capita gross domestic product (GDP) in São Paulo State (SP), Brazil. METHODS: Ecological study including live births residents in SP from 2004-2013. Neonatal deaths (0-27 days) with perinatal asphyxia were defined as intrauterine hypoxia, birth asphyxia or meconium aspiration syndrome written in any line of the Death Certificate. Geoprocessing analytical approach included detection of first order effects through quintiles and spatial moving average maps, followed by second order effects by global and local spatial autocorrelation (Moran and LISA, respectively) before and after smoothing with local Bayesian estimates. Finally, Spearman correlation was applied between asphyxia-associated neonatal mortality and mean per capita GDP rates for the municipalities with significant LISA. RESULTS: There were 6,713 asphyxia-associated neonatal deaths among 5,949,267 live births (rate: 1.13/1000) in SP. Spatial moving average maps showed a non-random distribution among municipalities, with presence of clusters (I = 0.048; p = 0.023). LISA map identified clusters of asphyxia-associated neonatal mortality in the south, southeast and northwest. After applying local Bayes estimates, clusters were more pronounced (I = 0.589; p = 0.001). There was a partial overlap of the areas of higher asphyxia-associated neonatal mortality and lower mean per capita GDP. CONCLUSIONS: Spatial analysis identified cluster areas of high asphyxia-associated neonatal mortality and low per capita GDP rates, with a significant negative correlation. This optimized, structured, and hierarchical approach to identify high-risk areas of cause-specific neonatal mortality may be helpful for guiding public health efforts to decrease neonatal mortality.

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Background: In Brazil, secondary data for epidemiology are largely available. However, they are insufficiently prepared for use in research, even when it comes to structured data since they were often designed for other purposes. To date, few publications focus on the process of preparing secondary data. The present findings can help in orienting future research projects that are based on secondary data. Objective: Describe the steps in the process of ensuring the adequacy of a secondary data set for a specific use and to identify the challenges of this process. Methods: The present study is qualitative and reports methodological issues about secondary data use. The study material was comprised of 6,059,454 live births and 73,735 infant death records from 2004 to 2013 of children whose mothers resided in the State of São Paulo - Brazil. The challenges and description of the procedures to ensure data adequacy were undertaken in 6 steps: (1) problem understanding, (2) resource planning, (3) data understanding, (4) data preparation, (5) data validation and (6) data distribution. For each step, procedures, and challenges encountered, and the actions to cope with them and partial results were described. To identify the most labor-intensive tasks in this process, the steps were assessed by adding the number of procedures, challenges, and coping actions. The highest values were assumed to indicate the most critical steps. Results: In total, 22 procedures and 23 actions were needed to deal with the 27 challenges encountered along the process of ensuring the adequacy of the study material for the intended use. The final product was an organized database for a historical cohort study suitable for the intended use. Data understanding and data preparation were identified as the most critical steps, accounting for about 70% of the challenges observed for data using. Conclusion: Significant challenges were encountered in the process of ensuring the adequacy of secondary health data for research use, mainly in the data understanding and data preparation steps. The use of the described steps to approach structured secondary data and the knowledge of the potential challenges along the process may contribute to planning health research.

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OBJECTIVE: Vitamin A is commonly recommended as a treatment for diarrhea and undernutrition; however, little is known about the underlying cellular mechanisms. The aim of this study was to investigate the modulation of cell cycle by vitamin A derivatives (retinyl palmitate or retinol) in undernourished intestinal epithelial crypts (IEC-6). METHODS: IEC-6 cells were exposed to nutrient deprivation (no serum and no glutamine) and supplemented with retinyl palmitate or retinol at a range of 2 to 20 µM. Proliferation, apoptosis/necrosis, cell cycle process, and gene transcription were assessed. RESULTS: Nutrient deprivation for 6, 12, 24, or 48 h decreased cell proliferation, and retinyl palmitate further decreased it after 24 and 48 h. Apoptosis rates were reduced by undernourishment and further reduced by retinyl palmitate after 48 h; whereas necrosis rates were unaltered. Undernourishment induced overall cell quiescence, increased percentage of cells in G0/G1 phase and decreased percentage of cells in S phase after 12 h and in G2/M phases at 6, 12, and 24 h after treatment. Both retinoids also showed cell quiescence induction with less cells in G2/M phases after 48 h, whereas only retinol showed significant modulation of G0/G1 and S phases. Both retinoids also increased markers of cell differentiation Fabp and Iap gene transcriptions in about fivefold rates after 42 h. Furthermore, specific gene transcriptions related to MAP kinase signaling pathway regulation of cell differentiation and cell cycle regulation were triggered by retinoids in undernourished IEC-6, with higher levels of expression for Atf2 and C-jun genes. CONCLUSIONS: These findings indicated that both vitamin A derivatives induce further survival mechanisms in undernourished intestinal epithelial crypt cells. These mechanisms include increased cell quiescence, decreased apoptosis, increased cell differentiation, and transcription of genes related to MAP kinase signaling pathway.

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BACKGROUND: Population-based studies analyzing neonatal deaths in middle-income countries may contribute to design interventions to achieve the Sustainable Development Goals, established by United Nations. This study goal is to analyze the annual trend of neonatal mortality in São Paulo State, Brazil, over a 10-year period and its underlying causes and to identify maternal and neonatal characteristics at birth associated with neonatal mortality. METHOD: A population-based study of births and deaths from 0 to 27 days between 2004 and 2013 in São Paulo State, Brazil, was performed. The annual trend of neonatal mortality rate according to gestational age was analyzed by Poisson or by Negative Binomial Regression models. Basic causes of neonatal death were classified according to ICD-10. Association of maternal demographic variables (block 1), prenatal and delivery care variables (block 2), and neonatal characteristics at birth (block 3) with neonatal mortality was evaluated by Poisson regression analysis adjusted by year of birth. RESULTS: Among 6,056,883 live births in São Paulo State during the study period, 48,309 died from 0 to 27 days (neonatal mortality rate: 8.0/1,000 live births). For the whole group and for infants with gestational age 22-27, 28-31, 32-36, 37-41 and ≥ 42 weeks, reduction of neonatal mortality rate was, respectively, 18 %, 15 %, 38 %, 53 %, 31 %, and 58 %. Median time until 50 % of deaths occurred was 3 days. Main basic causes of death were respiratory disorders (25 %), malformations (20 %), infections (17 %), and perinatal asphyxia (7 %). Variables independently associated with neonatal deaths were maternal schooling, prenatal care, parity, newborn sex, 1st minute Apgar, and malformations. Cesarean delivery, compared to vaginal, was protective against neonatal mortality for infants at 22-31 weeks, but it was a risk factor for those with 32-41 weeks. CONCLUSIONS: Despite the significant decrease in neonatal mortality rate over the 10-year period in São Paulo State, improved access to qualified health care is needed in order to avoid preventable neonatal deaths and increase survival of infants that need more complex levels of assistance.

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