31 results on '"Neves PA"'
Search Results
2. Tracking maternal, infant, and young child nutrition in Brazil after a decade without evidence.
- Author
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Neves PA
- Subjects
- Infant, Child, Humans, Female, Brazil, Family, Breast Feeding, Infant Nutritional Physiological Phenomena, Nutritional Status, Child Nutritional Physiological Phenomena
- Published
- 2023
- Full Text
- View/download PDF
3. Improved estimates of foetal growth are associated with perinatal outcomes: A latent modelling approach in a population-based birth cohort.
- Author
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Lourenço BH, Neves PA, Cardoso MA, and Castro MC
- Subjects
- Infant, Newborn, Pregnancy, Child, Female, Humans, Fetal Development, Gestational Age, Prenatal Care, Growth Disorders, Birth Cohort, Premature Birth
- Abstract
Background: We aimed to estimate latent foetal growth conditions and explore their determinants among maternal characteristics and ultrasound biometric parameters. We additionally investigated the influence of foetal growth conditions on perinatal variables., Methods: We used data from live-born singletons in the Maternal and Child Health and Nutrition in Acre, Brazil (MINA-Brazil Study) population-based birth cohort. Maternal and perinatal characteristics were assessed in medical records from the maternity hospital and interviews with participants from July 2015 to June 2016. A sub-sample went through ultrasound examinations during the antenatal period, with assessment of foetal head and abdominal circumferences, and femur length. We estimated latent foetal growth conditions with a structural equation modelling framework, informed by the child's birth weight z-scores (BWZ) and birth length z-scores (BLZ) according to gestational age. Odds ratios and 95% confidence intervals (CIs) for the occurrence of perinatal events were estimated according to linear predictions of the latent variable., Results: We included 1253 participants. Latent foetal growth conditions explained 88.3% of BWZ and 53.7% of BLZ variation. Maternal elevated blood pressure, primiparity, smoking, malaria, and insufficient gestational weight gain negatively impacted foetal growth conditions. In the subsample (n = 499), ultrasound biometric parameters assessed at 28 weeks were positively associated with the latent variable, with the largest contribution from foetal abdominal circumference. Each standardised unit of predicted foetal growth conditions halved the chance for preterm birth (95% CI = 0.26, 0.74) and longer hospital stay (>3 days) (95% CI = 0.28, 0.88). Conversely, BWZ and BLZ were not independently associated with these perinatal variables in separate logistic regression models., Conclusions: Latent foetal growth conditions jointly encompassing weight gain and linear growth during gestation were negatively influenced by a scenario of dual burden of maternal morbidities, with perinatal implications., Competing Interests: Disclosure of interest: The authors completed the ICMJE Disclosure of Interest Form (available upon request from the corresponding author) and disclose no relevant interests., (Copyright © 2023 by the Journal of Global Health. All rights reserved.)
- Published
- 2023
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4. Levels and sources of hydrocarbons in the Patos Lagoon estuary and Cassino Beach mud bank (South Atlantic, Brazil): evidence of transference between environments.
- Author
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Neves PA, Costa PG, Portz LC, Garcia MR, and Fillmann G
- Subjects
- Estuaries, Geologic Sediments, Brazil, Environmental Monitoring, Hydrocarbons analysis, Water Pollutants, Chemical analysis, Polycyclic Aromatic Hydrocarbons analysis
- Abstract
This study assessed the concentrations and sources of natural and anthropogenic aliphatic (AHs) and polycyclic aromatic hydrocarbons (PAHs) in superficial sediments collected along the Patos Lagoon estuary and in sediment cores obtained from the Cassino Beach mud bank. Levels and distribution of n-alkanes indicate terrestrial sources, overlapping with a low amount of petrogenic hydrocarbons (heavy oils). Unresolved complex mixture (UCM) was observed in all samples. On the other hand, the distribution of PAHs in the sediments showed a predominance of pyrolytic over petrogenic sources. In general, hydrocarbons (HCs) contamination in the Patos Lagoon estuary and its adjacent coastal area can be considered low, except for sites near urban or industrial effluents, where moderate to high levels of contamination were found. Concentrations of hydrocarbons were homogeneous throughout the sediment cores, suggesting that mixing processes may have occurred along the layers or that HCs inputs to the mud banks were uniform during the studied deposition period. In addition, the levels and profile of HCs in the coastal sediments were similar to those observed in the estuary. Moreover, the frequent remobilization of sediments from the mud bank towards Cassino beach does not seem to pose any threats to the local biota or beach users since the levels of contamination were relatively low and below the threshold limits of sediment quality guidelines., (© 2023. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)
- Published
- 2023
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5. Breastfeeding: crucially important, but increasingly challenged in a market-driven world.
- Author
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Pérez-Escamilla R, Tomori C, Hernández-Cordero S, Baker P, Barros AJD, Bégin F, Chapman DJ, Grummer-Strawn LM, McCoy D, Menon P, Ribeiro Neves PA, Piwoz E, Rollins N, Victora CG, and Richter L
- Subjects
- Infant, Infant, Newborn, Humans, Female, Mothers, Marketing, Poverty, Breast Feeding, Milk Substitutes
- Abstract
In this Series paper, we examine how mother and baby attributes at the individual level interact with breastfeeding determinants at other levels, how these interactions drive breastfeeding outcomes, and what policies and interventions are necessary to achieve optimal breastfeeding. About one in three neonates in low-income and middle-income countries receive prelacteal feeds, and only one in two neonates are put to the breast within the first hour of life. Prelacteal feeds are strongly associated with delayed initiation of breastfeeding. Self-reported insufficient milk continues to be one of the most common reasons for introducing commercial milk formula (CMF) and stopping breastfeeding. Parents and health professionals frequently misinterpret typical, unsettled baby behaviours as signs of milk insufficiency or inadequacy. In our market-driven world and in violation of the WHO International Code for Marketing of Breast-milk Substitutes, the CMF industry exploits concerns of parents about these behaviours with unfounded product claims and advertising messages. A synthesis of reviews between 2016 and 2021 and country-based case studies indicate that breastfeeding practices at a population level can be improved rapidly through multilevel and multicomponent interventions across the socioecological model and settings. Breastfeeding is not the sole responsibility of women and requires collective societal approaches that take gender inequities into consideration., Competing Interests: Declaration of interests NR received grants from the Bill & Melinda Gates Foundation during the conduct of this study. All other authors declare no competing interests., (© 2023 World Health Organization; licensee Elsevier. This is an Open Access article published under the CC BY 3.0 IGO license which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. In any use of this article, there should be no suggestion that WHO endorses any specific organisation, products or services. The use of the WHO logo is not permitted. This notice should be preserved along with the article's original URL.)
- Published
- 2023
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6. Marketing of commercial milk formula: a system to capture parents, communities, science, and policy.
- Author
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Rollins N, Piwoz E, Baker P, Kingston G, Mabaso KM, McCoy D, Ribeiro Neves PA, Pérez-Escamilla R, Richter L, Russ K, Sen G, Tomori C, Victora CG, Zambrano P, and Hastings G
- Subjects
- Infant, Female, Child, Humans, Child, Preschool, Animals, Breast Feeding, Marketing, Health Policy, Parents, Infant Formula, Milk, Milk Substitutes
- Abstract
Despite proven benefits, less than half of infants and young children globally are breastfed in accordance with the recommendations of WHO. In comparison, commercial milk formula (CMF) sales have increased to about US$55 billion annually, with more infants and young children receiving formula products than ever. This Series paper describes the CMF marketing playbook and its influence on families, health professionals, science, and policy processes, drawing on national survey data, company reports, case studies, methodical scoping reviews, and two multicountry research studies. We report how CMF sales are driven by multifaceted, well resourced marketing strategies that portray CMF products, with little or no supporting evidence, as solutions to common infant health and developmental challenges in ways that systematically undermine breastfeeding. Digital platforms substantially extend the reach and influence of marketing while circumventing the International Code of Marketing of Breast-milk Substitutes. Creating an enabling policy environment for breastfeeding that is free from commercial influence requires greater political commitment, financial investment, CMF industry transparency, and sustained advocacy. A framework convention on the commercial marketing of food products for infants and children is needed to end CMF marketing., Competing Interests: Declaration of interests PB reports receiving funds from WHO to undertake research on the political economy of infant and young child feeding, which included research on CMF marketing. PB also reports funding from the Australian Research Council, UNICEF, The World Bank, and WHO to undertake research, prepare policy reviews, write reports, or attend meetings, outside the submitted work. GK was employed by M&C Saatchi World Services, which was commissioned by UNICEF and WHO to design and implement a multicountry study examining the scope and influence of CMF marketing. GH and DM report receiving funds from WHO to undertake qualitative and secondary research on the political economy of breastfeeding and other research describing the nature of CMF marketing. KR reports receiving a research grant from Alive & Thrive and FHI360 that supported earlier research that is now cited in this Series paper., (© 2023 World Health Organization; licensee Elsevier. This is an Open Access article published under the CC BY 3.0 IGO license which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. In any use of this article, there should be no suggestion that WHO endorses any specific organisation, products or services. The use of the WHO logo is not permitted. This notice should be preserved along with the article's original URL.)
- Published
- 2023
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7. Prelacteal feeding and its relationship with exclusive breastfeeding and formula consumption among infants in low- and middle-income countries.
- Author
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Neves PA, Armenta-Paulino N, Arroyave L, Ricardo LI, Vaz JS, Boccolini CS, Richter L, Peréz-Escamilla R, and Barros AJ
- Subjects
- Child, Infant, Female, Humans, Pregnancy, Retrospective Studies, Infant Food, Prenatal Care, Breast Feeding, Developing Countries
- Abstract
Background: Early feeding practices are important determinants of optimal feeding patterns later in life. We aimed to investigate if giving any fluids or foods other than breast milk during the first three days after birth (prelacteal feeds) affects exclusive breastfeeding and consumption of formula among children under six months of age in low and middle-income countries (LMICs)., Methods: We conducted a retrospective cohort study using data from 85 nationally representative Demographic Health Surveys (DHS) and Multiple Indicator Cluster Surveys (MICS) in LMICs (2010-2019). We considered three exposures: any prelacteal feeding (PLF), milk-based only prelacteal feeding (MLK), and water-based only prelacteal feeding (WTR), according to the DHS/MICS definition. The outcomes were exclusive breastfeeding, based on the World Health Organization definition, and consumption of formula among infants under six months of age. We used Poisson models adjusting for sociodemographic indicators, antenatal care, birth assistance, and early initiation of breastfeeding to estimate the effects of the exposures on the outcomes. Findings were grouped by each country, as well as by regions of the world and national income classification., Results: We included data from 91 282 children. PLF, MLK, and WTR had a prevalence of 33.9% (95% confidence interval (CI) = 33.6-34.2), 22.2% (95% CI = 21.9-22.4), and 9.4% (95% CI = 9.2-9.6), respectively. Exclusive breastfeeding and consumption of formula had a prevalence of 35.2% (95% CI = 34.9-35.5) and 27.7% (95% CI = 27.4-28.0), respectively. In the crude analysis, children who were given PLF were 40% less likely to be exclusively breastfed (prevalence ratio (PR) = 0.60; 95% CI = 0.56-0.64) and nearly twice more likely to receive formula (PR = 1.89; 95% CI = 1.72-2.08); the direction of the associations was the same across income groups and regions of the world. In the adjusted analysis, the observed crude effects were only slightly reduced (exclusive breastfeeding - PR = 0.62; 95% CI = 0.59-0.66, consumption of formula - PR = 1.72; 95% CI = 1.59-1.85). MLK showed a stronger impact on the outcomes than PLF, especially for formula consumption (adjusted PR = 1.81; 95% CI = 1.67-1.97) and in low-income countries. WTR was only negatively associated with exclusive breastfeeding (adjusted PR = 0.69; 95% CI = 0.63-0.75), but not with formula consumption (adjusted PR = 1.09; 95% CI = 0.99-1.20)., Conclusions: Feeding babies prelacteal foods shortens exclusive breastfeeding duration and increases the likelihood of formula consumption in children under six months of age in LMICs. Pro-breastfeeding interventions must be prioritized during antenatal care and throughout the stay in the maternity facility to properly protect, support, and promote exclusive breastfeeding since birth., Competing Interests: Disclosure of interest: The authors completed the ICMJE Disclosure of Interest Form (available upon request from the corresponding author) and disclose no relevant interests., (Copyright © 2022 by the Journal of Global Health. All rights reserved.)
- Published
- 2022
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8. New derivative of trans-dehydrocrotonin isolated from Croton cajucara shows reduced cytotoxic and genotoxic effects in hepatocellular carcinoma (HepG2) cell line.
- Author
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Silva de Carvalho V, Melo Lima KM, Calandrini de Azevedo LF, Panarra Ferreira Gomes das Neves PA, Borges RDS, Nagamachi CY, and Pieczarka JC
- Subjects
- Humans, Hep G2 Cells, DNA Damage, Cell Line, Croton, Carcinoma, Hepatocellular, Liver Neoplasms drug therapy, Antineoplastic Agents
- Abstract
The Croton cajucara (Euphorbiales, Euphorbiaceae) plant occurs widely in the Amazon region, where its leaves and stem bark are consumed by the population to treat several diseases. The secondary metabolite trans-dehydrocrotonin (DCTN) is mainly accountable for the biological activities of this plant. However, prolonged consumption is associated with hepatotoxic effects due to the furan ring present in the molecule. This group is responsible for toxicity reactions in other drugs. In this work, we inserted a COOH group into the molecule to prevent the formation of toxic intermediates. We assessed the cytotoxicity and genotoxicity of both molecules on HepG2 cells. Results showed that the new derivative (CCTN) is less cytotoxic and did not reduce cell viability at any concentration tested. Genotoxicity was also reduced as assessed by the comet and micronucleus assay. Therefore, the new derivative appears to be promising and additional tests should be performed to evaluate its therapeutic activities., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Ltd. All rights reserved.)
- Published
- 2022
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9. Unusual natural polycyclic aromatic hydrocarbons in sediment cores of an Amazon estuary.
- Author
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Neves PA, Santos FR, Araújo LD, Taniguchi S, Ferreira PAL, Figueira RCL, Lourenço RA, and Bícego MC
- Subjects
- China, Environmental Monitoring, Estuaries, Geologic Sediments, Sterols, Perylene, Polycyclic Aromatic Hydrocarbons analysis, Water Pollutants, Chemical analysis
- Abstract
Polycyclic aromatic hydrocarbons (PAHs) most likely derived from natural sources were observed in two sediment cores covering the last 100 years in an Amazon estuarine region. A considerable change in the PAHs main source was observed in the 1960s. Before the 1960s, the sources of PAHs seem to be related to biogenic and/or early-diagenetic processes. Concentrations of perylene were higher before the 1960s and suggest that its primary source to the sediments in the Amazon region is linked to a short-term diagenetic transformation of their biogenic precursors. The natural formation of alkylated PAHs in sediments was linked to the methylation of the parental aromatic hydrocarbons due to sediment maturation processes and the dehydrogenation of sterols in the sediments. The relatively rapid reaction occurring in recent sediments of the Amazon region suggests the importance of the microbial community in the transformation of biogenic precursors to alkylated-PAHs in the sediments., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Ltd. All rights reserved.)
- Published
- 2022
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10. Thought on Food: A Systematic Review of Current Approaches and Challenges for Food Intake Detection.
- Author
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Neves PA, Simões J, Costa R, Pimenta L, Gonçalves NJ, Albuquerque C, Cunha C, Zdravevski E, Lameski P, Garcia NM, and Pires IM
- Subjects
- Adolescent, Eating, Feeding Behavior, Food, Humans, Artificial Intelligence, Nutrition Assessment
- Abstract
Nowadays, individuals have very stressful lifestyles, affecting their nutritional habits. In the early stages of life, teenagers begin to exhibit bad habits and inadequate nutrition. Likewise, other people with dementia, Alzheimer's disease, or other conditions may not take food or medicine regularly. Therefore, the ability to monitor could be beneficial for them and for the doctors that can analyze the patterns of eating habits and their correlation with overall health. Many sensors help accurately detect food intake episodes, including electrogastrography, cameras, microphones, and inertial sensors. Accurate detection may provide better control to enable healthy nutrition habits. This paper presents a systematic review of the use of technology for food intake detection, focusing on the different sensors and methodologies used. The search was performed with a Natural Language Processing (NLP) framework that helps screen irrelevant studies while following the PRISMA methodology. It automatically searched and filtered the research studies in different databases, including PubMed, Springer, ACM, IEEE Xplore, MDPI, and Elsevier. Then, the manual analysis selected 30 papers based on the results of the framework for further analysis, which support the interest in using sensors for food intake detection and nutrition assessment. The mainly used sensors are cameras, inertial, and acoustic sensors that handle the recognition of food intake episodes with artificial intelligence techniques. This research identifies the most used sensors and data processing methodologies to detect food intake.
- Published
- 2022
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11. Consumption of breast milk, formula and other non-human milk by children aged under 2 years: analysis of eighty-six low- and middle-income countries.
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Neves PA, Barros AJ, Baker P, Piwoz E, Santos TM, Gatica-Domínguez G, Vaz JS, Rollins N, and Victora CG
- Subjects
- Breast Feeding, Female, Humans, Income, Infant, Poverty, Developing Countries, Milk, Human
- Abstract
Objective: To investigate the prevalence and socio-economic inequalities in breast milk, breast milk substitutes (BMS) and other non-human milk consumption, by children under 2 years in low- and middle-income countries (LMIC)., Design: We analysed the prevalence of continued breast-feeding at 1 and 2 years and frequency of formula and other non-human milk consumption by age in months. Indicators were estimated through 24-h dietary recall. Absolute and relative wealth indicators were used to describe within- and between-country socio-economic inequalities., Setting: Nationally representative surveys from 2010 onwards from eighty-six LMIC., Participants: 394 977 children aged under 2 years., Results: Breast-feeding declined sharply as children became older in all LMIC, especially in upper-middle-income countries. BMS consumption peaked at 6 months of age in low/lower-middle-income countries and at around 12 months in upper-middle-income countries. Irrespective of country, BMS consumption was higher in children from wealthier families, and breast-feeding in children from poorer families. Multilevel linear regression analysis showed that BMS consumption was positively associated with absolute income, and breast-feeding negatively associated. Findings for other non-human milk consumption were less straightforward. Unmeasured factors at country level explained a substantial proportion of overall variability in BMS consumption and breast-feeding., Conclusions: Breast-feeding falls sharply as children become older, especially in wealthier families in upper-middle-income countries; this same group also consumes more BMS at any age. Country-level factors play an important role in explaining BMS consumption by all family wealth groups, suggesting that BMS marketing at national level might be partly responsible for the observed differences.
- Published
- 2022
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12. Historical deposition of PAHs in mud depocenters from the Southwestern Atlantic continental shelf: The influence of socio-economic development and coal consumption in the last century.
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Timoszczuk CT, Dos Santos FR, Araújo LD, Taniguchi S, Lourenço RA, de Mahiques MM, de Lima Ferreira PA, Lopes Figueira RC, Neves PA, Prates D, and Bícego MC
- Subjects
- Brazil, China, Cities, Coal analysis, Economic Development, Environmental Monitoring, Geologic Sediments, Polycyclic Aromatic Hydrocarbons analysis, Water Pollutants, Chemical analysis
- Abstract
Polycyclic aromatic hydrocarbon (PAH) concentrations were determined in four dated sediment cores collected in mud depocenters of the southern Brazilian continental shelf. Core dating results covered the interval between 1925 and 2017. The total PAH concentrations (ΣPAHs) ranged from 44.69 ng g
-1 to 305.43 ng g-1 and were similar between the analysed cores. Fine-grained sediments and total organic carbon (TOC) results did not correlate with the ΣPAHs, indicating that the variations in PAH concentrations are mostly related to variations in sources and emissions. PAH source appointment indicated a high input of a natural compound (perylene) and the predominance of anthropogenic PAHs from coal, biomass, and fuel combustion. Alkylated PAHs presented high contributions throughout all cores. The historical deposition of PAHs was associated with different periods of the socio-economic and industrial development of near coastal cities and reflected very well the history of coal production and consumption in the southern region of Brazil. The low levels of ΣPAHs before 1945 in all analysed cores may be related to the beginning of the industrialization process and the lower urbanization degree in the region. Between 1945 and 1965, the gradual ΣPAHs increase reflects the establishment and enlargement of the southern Brazilian industrial sector. The interval between 1965 and 1990 corresponded to the highest ΣPAHs in three of the four analysed cores. After 1990, a relative decrease in the ΣPAHs was observed in most cores and may be related the multiple cuts of incentives to the industrial usage of coal, as well as to Brazil's efforts in environmental regulation for coal extraction and consumption., (Copyright © 2021 Elsevier Ltd. All rights reserved.)- Published
- 2021
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13. First-food systems transformations and the ultra-processing of infant and young child diets: The determinants, dynamics and consequences of the global rise in commercial milk formula consumption.
- Author
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Baker P, Santos T, Neves PA, Machado P, Smith J, Piwoz E, Barros AJD, Victora CG, and McCoy D
- Subjects
- China, Diet, Female, Humans, Infant, Infant Formula, Milk, Human, Breast Feeding, Infant Food
- Abstract
The inappropriate marketing and aggressive promotion of breastmilk substitutes (BMS) undermines breastfeeding and harms child and maternal health in all country contexts. Although a global milk formula 'sales boom' is reportedly underway, few studies have investigated its dynamics and determinants. This study takes two steps. First, it describes trends and patterns in global formula sales volumes (apparent consumption), by country income and region. Data are reported for 77 countries, for the years 2005-19, and for the standard (0-6 months), follow-up (7-12 m), toddler (13-36 m), and special (0-6 m) categories. Second, it draws from the literature to understand how transformations underway in first-food systems - those that provision foods for children aged 0-36 months - explain the global transition to higher formula diets. Total world formula sales grew by 115% between 2005 and 2019, from 3.5 to 7.4 kg/child, led by highly-populated middle-income countries. Growth was rapid in South East and East Asia, especially in China, which now accounts for one third of world sales. This transition is linked with factors that generate demand for BMS, including rising incomes, urbanisation, the changing nature of woman's work, social norms, media influences and medicalisation. It also reflects the globalization of the baby food industry and its supply chains, including the increasing intensity and sophistication of its marketing practices. Policy and regulatory frameworks designed to protect, promote and support breastfeeding are partially or completely inadequate in the majority of countries, hence supporting industry expansion over child nutrition. The results raise serious concern for global child and maternal health., (© 2020 The Authors. Maternal & Child Nutrition published by John Wiley & Sons Ltd.)
- Published
- 2021
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14. Anthropogenic and natural inputs of polycyclic aromatic hydrocarbons in the sediment of three coastal systems of the Brazilian Amazon.
- Author
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Lima EAR, Neves PA, Patchineelam SR, da Silva JFBR, Takiyama LR, Martins CC, Lourenço RA, Taniguchi S, Elias VO, and Bícego MC
- Subjects
- Brazil, Cities, Environmental Monitoring, Geologic Sediments, Polycyclic Aromatic Hydrocarbons analysis, Water Pollutants, Chemical analysis
- Abstract
Polycyclic aromatic hydrocarbons (PAHs) were measured in 32 surface sediment samples collected around three cities (Barcarena, Belém, and Santana) located on the coast of the Brazilian Amazon. The concentration of total PAHs ranged from lower than detection limit to 33,101 ng g
-1 in a sample from Barcarena and was related to a large aluminum industrial complex and port activities. In Belém, which is the most populated area in the Amazon region, PAHs were probably derived from untreated sewage discharge and inputs from a large municipal landfill. Pyrogenic PAHs were predominant in both cities, with a smaller contribution of petrogenic PAHs. Low alkylated PAH levels may be associated with small boats and ship traffic. Santana had low total PAH concentrations, with a predominance of unusual alkylated PAHs, probably related to diagenetic transformations of organic matter in the sediment. In general, PAH concentrations in the samples were low and may reflect baseline levels for this Amazon estuarine system.- Published
- 2021
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15. Agreement between antenatal gestational age by ultrasound and clinical records at birth: A prospective cohort in the Brazilian Amazon.
- Author
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Lourenço BH, Lima DL, Vivanco E, de Brito Fernandes R, Duarte M, Ribeiro Neves PA, de Castro MC, and Cardoso MA
- Subjects
- Adult, Brazil, Cohort Studies, Humans, Male, Prospective Studies, Registries statistics & numerical data, Young Adult, Birth Certificates, Gestational Age, Ultrasonography, Prenatal
- Abstract
This study aimed to assess agreement between antenatal estimates of gestational age by ultrasound and clinical records at birth in the Brazilian Amazon. Ultrasound examinations were scheduled during the second trimester for 578 pregnant women prospectively screened at primary health care units, following a standardized protocol for image quality control. A multistage algorithm was used to assess the best estimate of gestational age during the antenatal period, considering reliability of last menstrual period (LMP) and acceptable differences in relation to ultrasound estimates derived from fetal biparietal diameter and femur length. Agreement of antenatal estimates of gestational age confirmed by ultrasound and clinical records at birth was analyzed with Bland-Altman plots and kappa coefficients (preterm and postterm births). Overall, ultrasound examinations presented high quality (>90% of satisfactory images), and were adopted as the best estimate of gestational age among 83.4% of pregnant women, confirming reliable LMP in the remaining proportion. On average, difference in gestational age between antenatal estimates and clinical records was 0.43 week (95% CI: 0.32, 0.53). Classification of preterm births had a good agreement (kappa: 0.82, p<0.001), but a poor performance was observed for postterm births (kappa: -0.06, p = 0.92). Higher differences in gestational age were noted for participants with >11 years of education and cases of caesarean deliveries. In conclusion, high-quality ultrasound images from the second trimester of pregnancy based the assessment of gestational age, while reliability of LMP was limited. Information from clinical records at birth presented an acceptable agreement on average and for classification of preterm births, which is relevant for properly interpreting perinatal outcomes. Discrepancies in caesarean deliveries may warrant further investigation., Competing Interests: The authors have declared that no competing interests exist.
- Published
- 2020
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16. Organic contaminants and trace metals in the western South Atlantic upper continental margin: Anthropogenic influence on mud depocenters.
- Author
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Santos FR, Neves PA, Kim BSM, Taniguchi S, Lourenço RA, Timoszczuk CT, Sotão BMT, Montone RC, Figueira RCL, Mahiques MM, and Bícego MC
- Subjects
- Environmental Monitoring, Geologic Sediments, Metals, Polychlorinated Biphenyls analysis, Polycyclic Aromatic Hydrocarbons analysis, Water Pollutants, Chemical analysis
- Abstract
Trace metals, dichloro-diphenyl-trichloroethane (DDTs), polychlorinated biphenyls (PCBs), and polycyclic aromatic hydrocarbons (PAHs) were quantified in surface sediments from mud depocenters located in the western South Atlantic upper continental margin. There was no anthropogenic trace metal pollution observed, and the higher As values were attributed to high CaCO3 content in the area. The results indicate PCB sources associated with long-range atmospheric transport in addition to past DDT use for agriculture and pest control. PAHs were mainly originated from biomass and fossil fuel combustion, and their distribution is in alignment with the riverine runoff influence in southern region, which is transported towards the northern regions by coastal currents. Higher concentrations of 2-3 ring PAHs and DDTs in shallow and northern stations indicate a coastal influence. This work presents baseline information on the extent of anthropogenic influence in mud depocenters located in the western South Atlantic upper continental margin, showing these locations as potential source to sink of anthropogenic contaminants., Competing Interests: Declaration of competing interest None., (Copyright © 2020 Elsevier Ltd. All rights reserved.)
- Published
- 2020
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17. Depositional history of polychlorinated biphenyls (PCBs), organochlorine pesticides (OCPs) and polycyclic aromatic hydrocarbons (PAHs) in an Amazon estuary during the last century.
- Author
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Neves PA, Colabuono FI, Ferreira PAL, Kawakami SK, Taniguchi S, Figueira RCL, Mahiques MM, Montone RC, and Bícego MC
- Subjects
- Brazil, Estuaries, Environmental Monitoring, Hydrocarbons, Chlorinated analysis, Pesticides analysis, Polychlorinated Biphenyls analysis, Polycyclic Aromatic Hydrocarbons analysis, Water Pollutants, Chemical analysis
- Abstract
The sources and depositional history of OCPs (organochlorine pesticides), PCBs (polychlorinated biphenyls) and PAHs (polycyclic aromatic hydrocarbons) over the last 100years were determined in two sediment cores collected in the Amazon region. It was possible to distinguish two depositional periods along the cores. The first period occurred before extensive anthropogenic effects were registered in the sediments. During this time interval, the concentrations of all OCPs and PCBs were below the detection limits (DL), and the PAH concentrations were low and essentially constant (58.19-124.28ngg
-1 ). The second period starts in the mid-1960s and reflects the increased human influence in the area. The concentrations of OCPs, PCBs, and PAHs increased towards the top of the cores, varying between- -1 ,
- -1 and 331 to 2341ngg
-1 , respectively. In general, OCP results showed trends corresponding to the production, usage and prohibition periods of POPs in Brazil. Compounds related to wood treatment, such HCHs and chlordanes, were predominant among the OCPs, which may be associated with many sawmills located in this region. The increase in PAH concentration after the 1960s is mainly due to forest fires, caused by the implementation of large-scale cattle ranches, which burned forests to create pastures. The background PAH concentrations before the 1960s are probably related to natural diagenetic processes., (Copyright © 2017 Elsevier B.V. All rights reserved.)- Published
- 2018
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18. Expression of co-stimulatory molecules CD80 and CD86 is altered in CD14 + HLA-DR + monocytes from patients with Chagas disease following induction by Trypanosoma cruzi recombinant antigens.
- Author
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Soares AK, Neves PA, Cavalcanti MD, Marinho SM, Oliveira W Júnior, Souza JR, Lorena VM, and Gomes YM
- Subjects
- B7-1 Antigen immunology, B7-2 Antigen immunology, Cells, Cultured, Chronic Disease, HLA-DR Antigens immunology, Humans, Lipopolysaccharide Receptors immunology, Monocytes parasitology, Recombinant Proteins immunology, Antigens, Protozoan immunology, Chagas Disease immunology, Monocytes immunology
- Abstract
Introduction: The relationships between monocytes and lymphocytes through MHC class II molecules and costimulatory, are of utmost importance for the production of an efficient immune response. In this work, we assessed the expression of surface molecules CD80 and CD86 on CD14+HLA-DR+ monocytes from patients with Chagas disease., Methods:: The study population consisted of 31 patients with chronic clinical forms of Chagas disease. Patient blood samples were cultured in the presence of recombinant cytoplasmic repetitive antigen (CRA) and flagellar repetitive antigen (FRA)., Results:: We found considerable differences in the expression profile of surface molecules involved in antigen presentation., Conclusions:: CRA and FRA may contribute to host immune response evasion by Trypanozoma cruzi.
- Published
- 2016
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19. Clinical effect of photodynamic therapy on primary carious dentin after partial caries removal.
- Author
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Neves PA, Lima LA, Rodrigues FC, Leitão TJ, and Ribeiro CC
- Subjects
- Child, Colony Count, Microbial, Dentin microbiology, Dentin radiation effects, Female, Humans, Lactobacillus drug effects, Lactobacillus radiation effects, Lasers, Semiconductor therapeutic use, Male, Statistics, Nonparametric, Streptococcus mutans drug effects, Streptococcus mutans radiation effects, Time Factors, Treatment Outcome, Dental Caries drug therapy, Dentin drug effects, Enzyme Inhibitors administration & dosage, Methylene Blue administration & dosage, Photochemotherapy methods, Tooth, Deciduous microbiology
- Abstract
This study was conducted to assess the clinical effect of photodynamic therapy (PDT) in the decontamination of the deep dentin of deciduous molars submitted to partial removal of carious tissue. After cavity preparation, dentin samples were taken from the pulp wall of nineteen deciduous molars before and after PDT application. Remaining dentin was treated with 0.01% methylene blue dye followed by irradiation with an InGaAlP diode laser (λ - 660 nm; 40 mW; 120 J/cm2; 120 s). Dentin samples were microbiologically assessed for the enumeration of total microorganisms, Lactobacillus spp. and mutans streptococci. There was no significant difference in the number of colony-forming units (CFU) for any of the microorganisms assessed (p > 0.05). Photodynamic therapy, using 0.01% methylene blue dye at a dosimetry of 120 J/cm2 would not be a viable clinical alternative to reduce bacterial contamination in deep dentin.
- Published
- 2016
- Full Text
- View/download PDF
20. Determinants of gestational night blindness in pregnant women from Rio de Janeiro, Brazil.
- Author
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Saunders C, Leal Mdo C, Neves PA, Padilha Pde C, da Silva LB, and Schilithz AO
- Subjects
- Abortion, Induced, Adult, Anemia, Iron-Deficiency complications, Anemia, Iron-Deficiency drug therapy, Brazil epidemiology, Cross-Sectional Studies, Dietary Supplements, Female, Humans, Logistic Models, Night Blindness etiology, Night Blindness prevention & control, Postpartum Period, Pregnancy, Prenatal Care, Prevalence, Socioeconomic Factors, Vitamin A Deficiency complications, Vitamin A Deficiency drug therapy, Young Adult, Ascorbic Acid administration & dosage, Folic Acid administration & dosage, Food, Fortified, Iron, Dietary administration & dosage, Night Blindness epidemiology, Vitamin A administration & dosage
- Abstract
Objective: To describe the prevalence and determinants of gestational night blindness in pregnant women receiving care in a hospital in Rio de Janeiro, Brazil., Design: Cross-sectional study of pregnant and postpartum women receiving care in a public hospital in Rio de Janeiro from 1999 to 2001 (group I; n 225) or from 2005 to 2008 (group II; n 381). Night blindness was identified through a standardized and validated interview (WHO, 1996). The determinants of gestational night blindness were identified through a hierarchical logistic regression model., Setting: Public maternity hospital in Rio de Janeiro, RJ, Brazil., Subjects: Adult pregnant and postpartum women (n 606), aged ≥20 years., Results: The prevalence of gestational night blindness was 9·9 %. The final model revealed that not living in the South Zone of Rio de Janeiro (distal level: adjusted OR=1·846; 95 % CI 1·002, 3·401), belonging to group I (intermediate level: adjusted OR=2·183; 95 % CI 1·066, 4·471) and for the proximal level, having a history of abortion (adjusted OR=2·840; 95 % CI 1·134, 7·115) and having anaemia during the first and second trimesters of pregnancy (adjusted OR=3·776; 95 % CI 1·579, 9·029) were determinants of gestational night blindness., Conclusion: Gestational night blindness should be assessed for during the prenatal care of all pregnant women, especially those living in deprived areas of the city and/or who have a history of abortion or anaemia. Nutritional monitoring is recommended during pregnancy to control gestational night blindness.
- Published
- 2016
- Full Text
- View/download PDF
21. Breastfeeding, Dental Biofilm Acidogenicity, and Early Childhood Caries.
- Author
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Neves PA, Ribeiro CC, Tenuta LM, Leitão TJ, Monteiro-Neto V, Nunes AM, and Cury JA
- Subjects
- Analysis of Variance, Cross-Over Studies, Female, Humans, Hydrogen-Ion Concentration, Infant, Lactobacillus isolation & purification, Male, Microelectrodes, Saliva microbiology, Streptococcus mutans isolation & purification, Sucrose chemistry, Time Factors, Biofilms growth & development, Breast Feeding adverse effects, Dental Caries epidemiology, Dental Caries etiology, Milk, Human chemistry, Tooth, Deciduous microbiology
- Abstract
Aim: This study evaluated the acidogenicity of human milk by the dental biofilms of children with and without early childhood caries (ECC)., Method: Biofilms of 16 children (7 with ECC; 9 caries free) were exposed to human milk or 10% sucrose solution in the crossover design, and the biofilm pH was determined., Results: Breastfeeding did not provoke a decrease in biofilm pH, irrespective of the children's caries status, whereas sucrose decreased the pH for both groups. In addition, higher x0394;pH5min (pH variation occurring at 5 min) was observed in the biofilms of ECC children (p < 0.05). The results suggest that breastfeeding may not contribute to ECC., (© 2016 S. Karger AG, Basel.)
- Published
- 2016
- Full Text
- View/download PDF
22. Vitamin A supplementation in Brazilian pregnant and postpartum women: a systematic review.
- Author
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Neves PA, Saunders C, Barros DC, and Ramalho A
- Subjects
- Brazil, Female, Humans, Milk, Human, Postpartum Period, Pregnancy, Vitamin A Deficiency, Dietary Supplements adverse effects, Vitamin A administration & dosage
- Abstract
Objective: To assess the impact of vitamin A supplementation on adult pregnant and puerperal women in Brazil regarding the content of vitamin A and secretory immunoglobulin A on colostrum and breast milk, in child's health conditions, and in mother-child binomial vitamin A status., Methods: A research was conducted in Medline, Scopus, Web of Science, and Lilacs electronic databases for the studies published between January 2000 and January 2014. The methodological quality of the studies was assessed according to Jadad scale. The study search was conducted in January 2014, independently by two authors., Results: Seven studies were found concerning the effects of vitamin A supplementation in the puerperal period on breast milk and infant morbidity. No study regarding pregnant women supplementation was found. The supplementation in the puerperal period raised the retinol content on breast milk, thus increasing the offer of vitamin A for the child and the concentration of secretory immunoglobulin A on colostrum. There was no description of effects on infant morbidity., Conclusion: It seems that the advantages of postpartum supplementation were not established in the Brazilian program, although the supplementation contributes to a better nutritional status of vitamin A for both the child and the puerperal woman and increases the offer of vitamin A for the newborn through the breast milk.
- Published
- 2015
- Full Text
- View/download PDF
23. The role of prenatal nutrition assistance on the prevalence of night blindness in pregnant adults.
- Author
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Ribeiro Neves PA, Ramalho A, De Carvalho Padilha P, and Saunders C
- Subjects
- Adult, Anthropometry, Brazil epidemiology, Cross-Sectional Studies, Female, Humans, Infant, Newborn, Postpartum Period, Pregnancy, Prevalence, Young Adult, Night Blindness epidemiology, Night Blindness prevention & control, Prenatal Care statistics & numerical data, Prenatal Nutritional Physiological Phenomena
- Abstract
Introduction: In developing countries, night blindness is a very common public health problem among pregnant women., Objective: Evaluate the effect of the changes occurred on prenatal care concerning prenatal nutritional care on the occurrence of night blindness (XN) in adult pregnant women in public maternity hospital in Rio de Janeiro between 1999-2001 and between 2007-2008., Methods: Two cross-sectional studies were conducted, been the first one conducted between 1999-2001 and the second one between 2007-2008. Were studied 402 puerperal women, 225 between 1999-2001 (GI) and 177 between 2007-2008 (GII). The gestational XN was investigated during the immediate puerperium (GI) and during the prenatal/puerperium (GII), diagnosed by the World Health Organization. The study collected sociodemographic, clinical, obstetric, anthropometric and prenatal care information., Results: It verified significant reduce of prevalence of gestational XN (GI = 18.7% e GII = 0.6%, p < 0.001). The occurrence of gestational XN was associated to sanitary conditions, education level, more than six prenatal consultations, miscarriage at last pregnancy, higher average number of deliveries, average number of prenatal care consultations and prenatal nutritional (p < 0.05). There was no association between gestational XN and marital status, skin color, pre-gestational nutritional status, adequacy of gain of total gestational weight, gestational anaemia and average number of pregnancies (p > 0.05)., Conclusion: The inclusion of nutritional care in routine prenatal care may have contributed to the reduction of gestational XN. Studies to assess the nutritional intervention in the prevention and treatment of gestational XN at regions at greatest risk are suggested., (Copyright AULA MEDICA EDICIONES 2014. Published by AULA MEDICA. All rights reserved.)
- Published
- 2014
- Full Text
- View/download PDF
24. Systematic review; Nutritional therapy in gestational diabetes mellitus.
- Author
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Thomaz de Lima H, Lopes Rosado E, Ribeiro Neves PA, Corrêa Monteiro Machado R, Mello de Oliveira L, and Saunders C
- Subjects
- Adult, Dietary Carbohydrates, Female, Humans, Pregnancy, Diabetes, Gestational diet therapy, Nutrition Therapy methods
- Abstract
Introduction: Several methods of dietetic counseling can be used in the nutritional therapy in gestational diabetes mellitus (GDM). The main methods are the traditional method (TM) and the carbohydrate counting (CCM)., Objective: Presenting a systematic review of the literature on the impact of nutritional therapy in GDM, through TM and CCM, evaluating the results for maternal and child health., Methods: We searched databases PubMed, Scopus, Web of Science, Lilacs and CAPES Digital Bank of Thesis. The methodological quality of all the studies included was made using the Jadad score., Results and Conclusion: We have found five studies that evaluated the effects of nutritional therapy, through the TM, on the maternal and child health. None study evaluating the CCM was detected in pregnant women with GDM Nutritional therapy given during antenatal care was effective in reducing pregnancy complications (preeclampsia, excessive gestational weight gain, necessity for cesarean delivery, for insulin therapy and for shoulder dystocia), perinatal complications (macrosomia, neonatal hypoglycemia, and birth weight) and also in better glycemic control. The use of nutritional therapy should be highlighted within the antenatal care for pregnant women with GDM, giving the satisfactory results on metabolic control and on pregnancy outcomes. Studies examining the CCM to GDM patients should be conducted to show its effects on maternal and child health.
- Published
- 2013
- Full Text
- View/download PDF
25. Quantitative (stereological) and qualitative study of rat epididymis after vasectomy and percutaneous epididymal sperm aspiration.
- Author
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Saade RD, Neves PA, Glina S, D'Ancona CA, Dambros M, and Lúcio MA
- Subjects
- Animals, Male, Rats, Rats, Wistar, Epididymis pathology, Sperm Retrieval, Vasectomy
- Abstract
Purpose: We investigated whether viable spermatozoa could be obtained from the rat epididymis after vasectomy by up to 5 percutaneous epididymal sperm aspiration punctures. We analyzed the inflammatory and scar forming histological alterations to the epididymis due to these punctures. Epididymal smooth muscle fiber and collagen density were also analyzed., Materials and Methods: A total of 50 rats that underwent bilateral vasectomy were divided into 5 groups of 10 each. Groups 1 to 5 underwent 1 to 5 right transscrotal percutaneous epididymal sperm aspiration punctures, respectively. Sperm quantification, and histological and stereological analyses were done on the punctured epididymides., Results: A mean of 48.78 x 10(6), 37.55 x 10(6), 26.33 x 10(6), 33.90 x 10(6) and 41.34 x 10(6)/ml spermatozoa were recovered in groups 1 to 5, respectively. A cumulative effect of the punctures was only observed in the variables of lymphoplasmacytic infiltrate and fibrosis, thus, showing that groups 1 and 2 differed significantly from groups 3 to 5. Stereological analysis revealed that conjunctive tissue volumetric density was 21.56%, 27.60%, 35.67%, 37.56%, 38.60% and 22.30% on the punctured side in groups 1 to 5 and controls, respectively (p <0.05)., Conclusions: Spermatozoa were obtained from all groups. All animals showed significant histological alterations in the epididymides from the second puncture and thereafter except with regard to necrosis. The cumulative effect of percutaneous epididymal sperm aspiration was only shown by lymphoplasmacytic infiltrate and fibrosis. Stereological analysis showed increased conjunctive tissue volumetric density from the second puncture and thereafter.
- Published
- 2008
- Full Text
- View/download PDF
26. Finasteride-associated male infertility.
- Author
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Glina S, Neves PA, Saade R, Netto NR Jr, Soares JB, and Galuppo AG
- Subjects
- Adult, Humans, Infertility, Male diagnosis, Male, Alopecia drug therapy, Enzyme Inhibitors adverse effects, Finasteride adverse effects, Infertility, Male chemically induced, Spermatogenesis drug effects
- Abstract
Finasteride is a potent and specific inhibitor of the 5alpha-reductase enzyme in men. Clinical studies have shown that finasteride 1mg/day is effective for promoting hair growth in men with male pattern hair loss. However, there is a concern about the use of finasteride, especially in young fertile patients, because of its action on testosterone metabolism. This paper describes 3 cases of young patients who had very poor seminal quality during finasteride treatment (1 mg/day), and their seminal quality greatly improved after cessation of finasteride treatment. Two of them presented with a left varicocele and the other was obese. We hypothesize that finasteride may not dramatically change the spermatogenesis process in healthy men, but in patients with conditions related to infertility, an amplification of the negative influence of finasteride could occur. Future studies should be done to clarify the extent of the effect of finasteride in patients fertility problems.
- Published
- 2004
- Full Text
- View/download PDF
27. Evaluation of human sperm membrane integrity using the water test and the hypoosmotic test.
- Author
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Bahamondes L, Fazano F, De Lucio MA, Neves PA, Bottcher Luiz F, and Lorenzetti GB
- Subjects
- Citrates, Fluorescent Dyes, Fructose, Humans, Male, Sodium Citrate, Cell Membrane physiology, Hypotonic Solutions, Spermatozoa ultrastructure, Water
- Abstract
The objective of the study was to compare the water test and the hypoosmotic test (HOS) in the assessment of the human sperm membrane. A total of 686 semen samples from human male donors were subjected to water and HOS tests after routine semen evaluation. The mean percentage of swollen spermatozoa was 71.8 +/- 9.6% in the HOS test and 67.8 +/- 9.4% for the water test; these values were not statistically different. The correlation of coefficients between the water test and the HOS test was highly significant whether the values for the HOS test were higher or lower than 60% (P < 0.001). A poor correlation was obtained when the two tests were compared for sperm counts either higher or lower than 20 x 6 ml-1 and when the results for both tests were compared with the percentage of eosin-Y staining spermatozoa. A poor correlation was also obtained when the results of each test were compared with eosin-Y staining spermatozoa in normal and abnormal semen samples. The coefficient of regression between the two tests showed a high correlation (P < 0.001). In conclusion, even though a high correlation between the HOS test and water test was observed in this study, it is not possible to recommend assessment of sperm membrane integrity using the water test and the consequent replacement of the HOS test in routine practice. Further studies are necessary to establish the best test for sperm vitality.
- Published
- 2001
- Full Text
- View/download PDF
28. Transurethral resection of partially obstructed ejaculatory ducts: seminal parameters and pregnancy outcomes according to the etiology of obstruction.
- Author
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Netto NR Jr, Esteves SC, and Neves PA
- Subjects
- Adult, Algorithms, Cysts complications, Cysts surgery, Female, Genital Diseases, Male etiology, Humans, Infertility, Male etiology, Male, Postoperative Complications, Pregnancy, Semen, Ejaculatory Ducts, Genital Diseases, Male surgery, Infertility, Male surgery, Pregnancy Outcome
- Abstract
Purpose: We determine how transurethral resection of the ejaculatory ducts performed for infertility affects seminal parameters and pregnancy outcomes in patients with partial ejaculatory duct obstruction due to a congenital or acquired etiological factor., Materials and Methods: Based on history and physical examination, hormonal profiles, semen analyses, transrectal ultrasonography and vasography findings partial ejaculatory duct obstruction was diagnosed in 14 men a mean of 30 years old who presented for infertility evaluation. Patients were grouped according to congenital or acquired cause of obstruction. Transurethral resection of the ejaculatory ducts was performed using the standard resectoscope loop technique. Clinical outcome was assessed by postoperative analyses of seminal parameters and pregnancy reports., Results: Transurethral resection of the ejaculatory ducts significantly improved semen quality (ejaculate volume and percentage of sperm motility) in all patients in the congenital group, while all but 1 (83%) had an improved sperm count. Pregnancy was achieved via sexual intercourse by 66% of the patients an average of 5.7 months postoperatively. Of the acquired etiological factor group 37.5% had improved semen quality after transurethral resection of ejaculatory duct and 12.5% achieved pregnancy via sexual intercourse. Postoperative complications occurred at a similar rate in each group (33%). However, complications in the congenital etiology group were minor, while 25% of the men in the acquired group had significant impairment of seminal parameters after transurethral resection of the ejaculatory ducts., Conclusions: Semen quality improvement and pregnancy outcome after transurethral resection of the ejaculatory ducts for partial ejaculatory duct obstruction differ significantly according to the main etiological cause of obstruction. An equivocal diagnosis of partial obstruction and technical problems during transurethral resection of the ejaculatory ducts may contribute to failure. However, in some cases the reason for failure remains unclear.
- Published
- 1998
- Full Text
- View/download PDF
29. Learning in the combinatorial neural model.
- Author
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Machado RJ, Barbosa VC, and Neves PA
- Abstract
The combinatorial neural model (CNM) is a type of fuzzy neural network for classification problems and, more generally, for the mapping between fuzzy multidimensional spaces. Learning in CNM is a complex task spanning the learning of input-neuron membership functions, of the network topology, and of connection weights. In this paper we are concerned with these various aspects of learning in CNM, most notably with the learning of connection weights, whose complexity comes from the existence of nondifferentiable, nonconvex error functions associated with the learning process. We introduce several algorithms for weight learning, most based on subgradient techniques borrowed from the field of nondifferentiable optimization. All algorithms are based on essentially "local" rules, and are therefore amenable to distributed/parallel implementations. Experimental results are provided on the large-scale problem of monitoring the deforestation of the Amazon region on satellite images. What these results indicate is that a hybrid CNM system outperforms previous results obtained with variations of error backpropagation techniques. In addition, this hybrid system has demonstrated robustness in the context under consideration, therefore constituting an attractive alternative.
- Published
- 1998
- Full Text
- View/download PDF
30. Correlation between hypo-osmotic swelling test and 'water test' to assess human sperm membrane integrity.
- Author
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Fazano F, Burmeister ML, de Lucio MA, Bottcher Luiz F, Neves PA, and Bahamondes L
- Subjects
- Citrates, Citric Acid, Fructose, Humans, Male, Osmotic Pressure, Spermatozoa physiology, Cell Membrane physiology, Hypotonic Solutions, Spermatozoa ultrastructure, Water
- Abstract
Fifty-nine men who requested vasectomy and 43 infertile patients had a semen analysis performed prior to surgery or during evaluation. A hypo-osmotic swelling test (HOS) and a new 'Water test' were performed simultaneously, in order to assess correlation between these two procedures. Our results showed that values obtained with the 'Water test' were significantly higher than those obtained with the HOS test (P < 0.001). These findings suggest that it is necessary to determine normal values for this new test before introducing it in the routine semen analysis.
- Published
- 1993
- Full Text
- View/download PDF
31. Surgical treatment of obstructive azoospermia.
- Author
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Rodrígues Netto Júnior N, Claro JA, Neves PA, and Nobrega Júnior VD
- Subjects
- Adult, Aged, Follow-Up Studies, Genital Diseases, Male complications, Humans, Male, Middle Aged, Oligospermia etiology, Oligospermia surgery
- Abstract
The records of 325 azoospermic patients were reviewed. A total of 109 patients (33.5%) had obstructive azoospermia and 48 of them underwent surgical treatment. Three patients had vas deferens agenesia and underwent artificial spermatocele; 14 with epididymal obstruction were treated by an end-to-end microsurgical vasoepididymostomy; and 31 vasectomized patients were submitted to microsurgical reversal. There was no pregnancy in the spermatocele patients. In the vasoepididymostomy patients 60% became patent and 30% achieved pregnancy. In the reversal group 90% of patency and pregnancy rate of 80% were observed, in a mean follow-up of 21 months. The last 8 cases were treated with a biological glue and 7 showed patency and one pregnancy in a 3-month follow-up period. One was lost to follow-up.
- Published
- 1992
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