RESUMO
BACKGROUND: The Aspirin Supplementation for Pregnancy Indicated Risk Reduction In Nulliparas trial was a landmark study that demonstrated a reduction in preterm birth and hypertensive disorders of pregnancy in nulliparous women who received low-dose aspirin. All women in the study had at least 1 moderate-risk factor for preeclampsia (nulliparity). Unlike current US Preventative Service Task Force guidelines, which recommend low-dose aspirin for ≥2 moderate-risk factors, women in this study were randomized to receive low-dose aspirin regardless of the presence or absence of an additional risk factor. OBJECTIVE: This study aimed to compare how low-dose aspirin differentially benefits nulliparous women with and without additional preeclampsia risk factors for the prevention of preterm birth and hypertensive disorders of pregnancy. STUDY DESIGN: This was a non-prespecified secondary analysis of the Aspirin Supplementation for Pregnancy Indicated Risk Reduction In Nulliparas trial that randomized nulliparous women with singleton pregnancies from 6 low-middle-income countries to receive low-dose aspirin or placebo. Our primary exposure was having an additional preeclampsia risk factor beyond nulliparity. Our primary outcome was preterm birth before 37 weeks of gestation, and our secondary outcomes included preterm birth before 34 weeks of gestation, preterm birth before 28 weeks of gestation, hypertensive disorders of pregnancy, and perinatal mortality. RESULTS: Among 11,558 nulliparous women who met the inclusion criteria, 66.8% had no additional risk factors. Low-dose aspirin similarly reduced the risk of preterm birth at <37 weeks of gestation in women with and without additional risk factors (relative risk: 0.75 vs 0.85; P=.35). Additionally for our secondary outcomes, low-dose aspirin similarly reduced the risk of preterm birth at <28 weeks of gestation, hypertensive disorders of pregnancy, and perinatal mortality in women with and without additional risk factors. The reduction of preterm birth at <34 weeks of gestation with low-dose aspirin was significantly greater in women without additional risk factors than those with an additional risk factor (relative risk: 0.69 vs 1.04; P=.04). CONCLUSION: Low-dose aspirin's ability to prevent preterm birth, hypertensive disorders of pregnancy, and perinatal mortality was similar in nulliparous women with and without additional risk factors. Professional societies should consider recommending low-dose aspirin to all nulliparous women.
Assuntos
Hipertensão Induzida pela Gravidez , Morte Perinatal , Pré-Eclâmpsia , Nascimento Prematuro , Gravidez , Recém-Nascido , Feminino , Humanos , Masculino , Nascimento Prematuro/epidemiologia , Nascimento Prematuro/prevenção & controle , Pré-Eclâmpsia/diagnóstico , Pré-Eclâmpsia/epidemiologia , Pré-Eclâmpsia/prevenção & controle , Hipertensão Induzida pela Gravidez/tratamento farmacológico , Aspirina/uso terapêutico , Fatores de RiscoRESUMO
OBJECTIVES: Rates of perinatal depression and pregnancy hyperglycemia are higher in Hispanic women as compared to non-Hispanic white women. In turn, depressive symptoms may reduce a woman's ability to engage in lifestyle changes that could reduce their subsequent diabetes risk. METHODS: We conducted a secondary analysis using data from Estudio Parto to evaluate sociodemographic, behavioral, psychosocial, and medical factors associated with perinatal depressive symptoms. Estudio Parto was a randomized controlled trial conducted in Western Massachusetts from 2013 to 17. Eligible participants had pregnancy hyperglycemia. The Edinburgh Postnatal Depression Scale (EPDS) was administered at 24-28 weeks gestation and at 6 weeks, 6 months, and 12 months postpartum. An EPDS cutpoint of 10 or greater defined the presence of depressive symptoms. RESULTS: In this sample of Puerto Rican women with pregnancy hyperglycemia, 32% and 27% showed prenatal and postpartum depressive symptoms, respectively. Among participants, 35.5% were diagnosed with GDM, 44.3% with isolated hyperglycemia, and 20.2% with impaired glucose tolerance. In multivariable models, being unmarried (OR 3.87; 95% CI 1.51-9.94), prenatal substance use (smoking or alcohol consumption; OR 2.96; 95% CI 1.41-6.18), and maternal age (1.11 for each year; 95% CI 1.04-1.18) were associated with higher odds of prenatal depressive symptoms. None of the risk factors were associated with subsequent postpartum depression in adjusted analyses. CONCLUSIONS: Identifying factors associated with prenatal and postpartum depression in Puerto Rican women with pregnancy hyperglycemia can inform targeted lifestyle interventions in this at-risk group, increase the likely adoption of healthy lifestyle behaviors, and thereby work to address health disparities. CLINICALTRIALS: gov NCT01679210; date of registration 08/07/2012.
Assuntos
Depressão Pós-Parto , Hiperglicemia , Depressão/diagnóstico , Depressão Pós-Parto/epidemiologia , Depressão Pós-Parto/psicologia , Feminino , Hispânico ou Latino , Humanos , Hiperglicemia/epidemiologia , Período Pós-Parto , Gravidez , Fatores de RiscoRESUMO
PURPOSE OF REVIEW: Since the 1900s, activity restriction (AR) has been widely prescribed as a strategy for preventing preterm birth (PTB). Over the past decade, the practice has been called into question as numerous studies have demonstrated that AR does not improve obstetrical and perinatal outcomes but does confer significant physical and psychological risks. The purpose of this review is to offer clinicians a summary of the latest data on the risks, benefits, and efficacy of AR for the prevention of PTB. RECENT FINDINGS: Both retrospective and prospective studies have demonstrated that AR does not significantly prolong pregnancy including those with multiple gestations, short cervices, ruptured membranes, and increased body mass indexes. Several studies have also shown that physical activity during pregnancy is associated with a higher incidence of vaginal delivery, a lower incidence of gestational diabetes mellitus, and a lower incidence of hypertensive disorders without increasing the risk of adverse neonatal outcomes. SUMMARY: The culmination of these data led to the Society for Maternal-Fetal Medicines' release of an updated committee recommendation in August of 2020; AR should not be routinely prescribed as a treatment to prevent PTB.
Assuntos
Nascimento Prematuro , Parto Obstétrico , Feminino , Humanos , Recém-Nascido , Gravidez , Gravidez Múltipla , Nascimento Prematuro/prevenção & controle , Estudos Prospectivos , Estudos RetrospectivosRESUMO
BACKGROUND: The American College of Obstetricians and Gynecologists currently recommends that antibiotic treatment should be considered for women with isolated maternal fevers during labor. However, there is little known about the maternal and neonatal impact of antibiotic treatment in this scenario. OBJECTIVE: We sought to assess the outcomes in women with a nonsustained, isolated maternal fever treated with antibiotics and compare it with expectant management. STUDY DESIGN: This was a retrospective cohort study of laboring women with a singleton gestation at term and a single temperature of between 38.0°C and 38.9°C without other evidence of infection (leukocytosis >15,000/mm3, fetal tachycardia, malodorous amniotic fluid, suspected alternate source of infection) at a tertiary teaching hospital. A contemporaneously maintained, validated obstetrical database was used to identify women for our cohort. Women with rheumatologic or renal disease, nongestational diabetes, preterm labor, placental abruption, vaginal bleeding, HIV, malpresentation, and fetal anomalies were excluded. The primary outcome was a postpartum fever above 38.0°C. Secondary maternal outcomes were treatment for postpartum endometritis, uterine atony, postpartum hemorrhage, admission to the intensive care unit, and postpartum length of stay. Secondary neonatal outcomes were neonatal intensive care unit admission, 5-minute Apgar score of <7, 5-minute Apgar score of <4, neonatal intensive care unit length of stay, and neonatal antibiotic administration. The results were compared using univariable and multivariable analyses. RESULTS: From January 1, 2015, to December 31, 2018, 359 women were identified; 85 received antibiotics and 274 did not. The baseline characteristics were similar between the groups, except for gestational age at the time of delivery (39.2 weeks vs 39.5 weeks for the antibiotic and no antibiotic groups, respectively; P=.02). The incidence in postpartum fever showed a downward trend in the antibiotic group (10.59% for the antibiotic group vs 18.98% for the no antibiotic group; P=.07). Significantly fewer women in the antibiotic group were treated for postpartum endometritis (3.53% vs 11.31%; P=.03). Neonatal intensive care unit admission and neonatal antibiotic administration rates were higher in the antibiotic group (41.18% vs 17.88%; P<.001 and 36.47% vs 12.41%; P<.001, respectively). The incidence of 5-minute Apgar score of <7 was higher in the antibiotic group (8.25% vs 2.19%; P=.016). After controlling for age, gestational age, body mass index, group B streptococci status, delivery method, parity, administration of epidural, and receipt of acetaminophen, the odds for postpartum fever were reduced by a factor of 0.42 (95% confidence interval, 0.18-0.99) among women who received antibiotics when compared with those who did not receive antibiotics. Outcome results are presented in Table 2. CONCLUSION: Although there was a lower rate of treatment for endometritis among women who received antibiotics for a single isolated maternal fever, there was a higher rate of neonatal intensive care unit admissions and 5-minute Apgar score of <7. This indicates that there likely is maternal benefit associated with antibiotic use, however, there are concerns about the neonatal risk.
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Antibacterianos/uso terapêutico , Parto Obstétrico , Febre/tratamento farmacológico , Trabalho de Parto , Complicações na Gravidez/tratamento farmacológico , Adulto , Bases de Dados Factuais , Endometrite , Feminino , Humanos , Recém-Nascido , Gravidez , Resultado da Gravidez , Estudos Retrospectivos , Adulto JovemRESUMO
BACKGROUND: Preterm birth is the leading cause of neonatal morbidity and mortality. Individuals who survive preterm birth are at a higher risk for many long-term adverse effects, including neurodevelopmental deficits. There are many well-established risk factors for worse neurologic outcomes spanning the prenatal and postnatal periods; however, investigators have yet to assess whether the cause of preterm birth has an impact on neurodevelopment. OBJECTIVE: Our objective was to assess whether neurologic outcomes differ by children born via indicated versus spontaneous preterm birth. STUDY DESIGN: We performed secondary analysis of a multicenter trial assessing magnesium for neuroprotection in women at risk for preterm delivery from 24 to 31 weeks. We included women with live, nonanomalous, singleton gestations who delivered preterm; we excluded women whose children were missing 2-year follow-up information for reasons other than perinatal demise. The primary exposure was type of preterm birth: (1) spontaneous if the child's mother presented with preterm labor or ruptured membranes, or (2) indicated if the child was delivered preterm iatrogenically. The primary outcome was death (including stillbirths, neonatal intensive care unit deaths, and deaths after discharge) or an abnormal Bayley II score by 2 years of age, defined as a Mental Developmental Index score or Psychomotor Developmental Index score 2 standard deviations below the mean. Secondary outcomes included death or Mental Developmental Index and Psychomotor Developmental Index scores 1 standard deviation or less, and neonatal morbidities associated with prematurity. Bivariate analyses of baseline characteristics by exposure were conducted. A logistic regression model was fitted to adjust for confounders. RESULTS: Of 1678 subjects, 1631 (97.2%) underwent spontaneous preterm birth and 47 (2.8%) underwent indicated preterm birth. Baseline maternal demographics and gestational age at delivery were similar between groups (29.6 weeks ± 7.8 versus 28.8 weeks ± 2.5, P = .07). A Psychomotor Developmental Index score 2 standard deviations or less below the mean or death occurred in 340 (20.9%) spontaneous preterm birth subjects and 17 (36.2%) indicated preterm birth subjects (P = .01). When adjusting for confounders, there remained an increased probability of a Psychomotor Developmental Index scores 2 standard deviations or less or death in indicated preterm birth subjects (P = .02). Although not statistically significant, indicated preterm birth was also associated with higher odds of Mental Developmental Index scores 2 standard deviations or less or death, Psychomotor Developmental scores 1 standard deviation or less or death, and Mental Developmental Index scores 1 standard deviation or less or death (1.76, 1.59, and 1.45, respectively). Limiting the analysis to small for gestational age infants, there was no difference in neurologic outcomes. The same was true for when we excluded small for gestational age infants from our analysis. However, after adjusting for small for gestational age, the odds of a Psychomotor Developmental Index score 2 standard deviations or less or death remained significant higher in the indicated preterm birth group (adjusted odds ratio, 1.98; 95% confidence interval, 1.01-3.88). CONCLUSION: In this cohort of pregnant women who delivered preterm, indicated deliveries were associated with worse psychomotor development than were spontaneous deliveries. Other outcomes appeared to be poor, but our numbers were limited. This finding should be confirmed in a larger cohort of women undergoing medically indicated preterm deliveries.
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Ruptura Prematura de Membranas Fetais , Nascimento Prematuro , Criança , Feminino , Idade Gestacional , Humanos , Lactente , Recém-Nascido de Baixo Peso , Recém-Nascido , Recém-Nascido Pequeno para a Idade Gestacional , Gravidez , Nascimento Prematuro/epidemiologiaRESUMO
OBJECTIVE: To evaluate the association between prenatal selective serotonin reuptake inhibitor (SSRI) exposure and postnatal therapeutic hypothermia for suspected hypoxic ischemic encephalopathy. STUDY DESIGN: Matched case-control study of singleton deliveries at a tertiary hospital from 2010 to 2016. Cases were infants treated with therapeutic hypothermia for suspected hypoxic ischemic encephalopathy. Controls were noncase infants, matched on gestational age, maternal age, obstetric provider group, and hospital shift. RESULT: Prenatal SSRI exposure occurred in 18.4% of cases compared with 4.1% of controls (aOR: 5.9, 95% CI: 1.8-19.7). Among all cases, 36.8% had evidence of hypoxic ischemic encephalopathy on postnatal MRI. In addition, 28.6% of SSRI-exposed cases and 38.7% of SSRI-unexposed cases had MRI confirmation of hypoxic ischemic encephalopathy, respectively. CONCLUSION: Future research to disentangle signs of SSRI exposure from true hypoxic ischemic encephalopathy may facilitate targeting therapeutic hypothermia stewardship toward infants more likely to benefit.
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Hipotermia Induzida , Hipóxia-Isquemia Encefálica/terapia , Inibidores Seletivos de Recaptação de Serotonina/efeitos adversos , Índice de Apgar , Estudos de Casos e Controles , Depressão/tratamento farmacológico , Feminino , Humanos , Recém-Nascido , Gravidez , Complicações na Gravidez/tratamento farmacológico , Efeitos Tardios da Exposição Pré-Natal , Inibidores Seletivos de Recaptação de Serotonina/uso terapêuticoRESUMO
Individually, D1 and D3 dopamine receptors (D1R and D3R, respectively) have been implicated in L-DOPA-induced dyskinesia (LID). Of late, direct D1R-D3R interactions have been linked to LID yet remain enigmatic. Therefore, the current research sought to characterize consequences of putative D1R-D3R interactions in dyskinesia expression and in LID-associated downstream cellular signaling. To do so, adult male Sprague-Dawley hemi-parkinsonian rats were given daily L-DOPA (6â¯mg/kg; s.c.) for 2 weeks to establish stable LID, as measured via the abnormal voluntary movements (AIMs) scale. Thereafter, rats underwent dose-response AIMs testing for the D1R agonist SKF38393 (0, 0.3, 1.0, 3.0â¯mg/kg) and the D3R agonist, PD128907 (0, 0.1, 0.3, 1.0â¯mg/kg). Each agonist dose-dependently induced dyskinesia, implicating individual receptor involvement. More importantly, when threshold doses were co-administered, rats displayed synergistic exacerbation of dyskinesia. Interestingly, this observation was not mirrored in general locomotor behaviors, highlighting a potentially dyskinesia-specific effect. To illuminate the mechanisms by which D1R-D3R co-stimulation led to in vivo synergy, levels of striatal phosphorylated extracellular signal-regulated kinase 1/2 (pERK1/2) were quantified after administration of SKF38393 and/or PD128907. Combined agonist treatment synergistically drove striatal pERK1/2 expression. Together, these results support the presence of a functional, synergistic interaction between D1R and D3R that manifests both behaviorally and biochemically to drive dyskinesia in hemi-parkinsonian rats.
Assuntos
Antiparkinsonianos/efeitos adversos , Discinesia Induzida por Medicamentos/metabolismo , Levodopa/efeitos adversos , Transtornos Parkinsonianos/tratamento farmacológico , Receptores de Dopamina D1/metabolismo , Receptores de Dopamina D3/metabolismo , 2,3,4,5-Tetra-Hidro-7,8-Di-Hidroxi-1-Fenil-1H-3-Benzazepina/farmacologia , Animais , Antiparkinsonianos/farmacologia , Benzopiranos/farmacologia , Corpo Estriado/efeitos dos fármacos , Corpo Estriado/metabolismo , Agonistas de Dopamina/farmacologia , Relação Dose-Resposta a Droga , Lateralidade Funcional , Levodopa/farmacologia , Masculino , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Atividade Motora/efeitos dos fármacos , Atividade Motora/fisiologia , Oxazinas/farmacologia , Oxidopamina , Transtornos Parkinsonianos/metabolismo , Ratos Sprague-Dawley , Receptores de Dopamina D1/agonistas , Receptores de Dopamina D3/agonistasRESUMO
BACKGROUND: Hidden hunger affects individuals who chronically consume an inadequate intake of at least 1 micronutrient and is associated with low dietary diversity. Little data are available on dietary intake or status assessment of B vitamins among preschool children in Zambia. OBJECTIVES: The aim of this study was to assess 24-hour dietary recall records obtained from Zambian children aged 3 to 7 years for B vitamin intake in relation to adequacy and change over time in the same community. METHODS: Twenty-four-hour dietary recalls were collected from 2 studies that were 2 years apart in the same district of Zambia. Data were retrospectively analyzed for B vitamin intake, that is, biotin, vitamin B12, folate, niacin, pantothenic acid, vitamin B6, riboflavin, and thiamin. The estimated average requirement (EAR) cut point method was used to assess inadequacy prevalence for EARs established by the Institute of Medicine in the United States. RESULTS: For all B vitamins, mean values were below the EARs established for children 4 to 8 years old. Relative to the EAR, children had the highest intakes of vitamin B6 with inadequacies of 77.9% and 60.1% in 2010 and 2012, respectively. The highest prevalence of inadequate intake was associated with folate, where ≥95% of the children had intakes below the EAR in both studies. CONCLUSIONS: All median vitamin B intakes were inadequate among these young children in rural Zambia. Future researchers and policy makers may need to consider B vitamin status in resource-poor areas of the country.
Assuntos
Dieta/estatística & dados numéricos , Complexo Vitamínico B , Deficiência de Vitaminas do Complexo B/epidemiologia , Criança , Pré-Escolar , Inquéritos sobre Dietas , Humanos , Prevalência , Estudos Retrospectivos , Zâmbia/epidemiologiaRESUMO
Increasing body mass indices (BMIs) across the globe reflect pandemic shifts towards habitual positive energy imbalances. Excess body fat in individuals is often associated with high-energy and high-fat diets scanty in fresh produce. Carotenoids are fat-soluble pigments plentiful in many fruits and vegetables. They are well-known for provitamin A and antioxidant functions, but little research has been done related to carotenoid-body mass interactions. Serum carotenoids were analyzed relative to body fat to determine correlations between major serum carotenoids, retinol, BMI, fat mass, and lean mass. Healthy women ( n = 76), 19-50 years old, were categorized into two comparison groups determined by percent body fat measured by air displacement plethysomography (BOD POD®), i.e. <31% and ≥31% fat mass. Anthropometric and three-day diet records were completed for BMI and nutrient intake calculations, respectively. Serum α-carotene concentrations were strongly inversely associated with all measures of body composition ( P < 0.001 α-carotene) controlling for dietary intake and age, while ß-carotene, lutein, and lycopene were not ( P > 0.05). Dietary intake between groups did not differ, including carrot consumption (a high dietary source of α-carotene). These results confirm previous carotenoid-health research and propose the need for further investigation of potential protective roles that α-carotene may perform for optimal health. Serum α-carotene may provide a deeper and clinically relevant purpose, beyond previous suggestions for its use as a biomarker for fruit and vegetable consumption, in that α-carotene may be a biomarker for chronic disease risk frequently linked with obesity. Impact statement Carotenoids are important pigments in fruit and vegetables and found in human serum. This study isolated a negative relationship between serum α-carotene and body fatness. As humans begin to live over a century, determining biomarkers of ultimate health is important. α-Carotene does not have the same distribution in the food supply as ß-carotene and therefore is often overlooked in surveys. In part, this is due to the fact that ß-carotene provides two molecules of vitamin A, while α-carotene provides one upon central cleavage. This study shows a very clear association between α-carotene and body fatness, which appears to go beyond its fat-soluble nature. Dietary intake data were not able to explain the association. Further work is needed to determine what dietary components infer health benefits.
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Biomarcadores/sangue , Carotenoides/sangue , Obesidade/sangue , Sobrepeso/sangue , Adulto , Índice de Massa Corporal , Feminino , Humanos , Pessoa de Meia-Idade , Pré-Menopausa , Adulto JovemRESUMO
UNLABELLED: Long-term treatment of Parkinson's disease with l-DOPA almost always leads to the development of involuntary movements termed l-DOPA-induced dyskinesia. Whereas hyperdopaminergic signaling in the basal ganglia is thought to cause dyskinesia, alterations in primary motor cortex (M1) activity are also prominent during dyskinesia, suggesting that the cortex may represent a therapeutic target. The present study used the rat unilateral 6-hydroxydopamine lesion model of Parkinson's disease to characterize in vivo changes in GABA and glutamate neurotransmission within M1 and determine their contribution to behavioral output. 6-Hydroxydopamine lesion led to parkinsonian motor impairment that was partially reversed by l-DOPA. Among sham-lesioned rats, l-DOPA did not change glutamate or GABA efflux. Likewise, 6-hydroxydopamine lesion did not impact GABA or glutamate among rats chronically treated with saline. However, we observed an interaction of lesion and treatment whereby, among lesioned rats, l-DOPA given acutely (1 d) or chronically (14-16 d) reduced glutamate efflux and enhanced GABA efflux. Site-specific microinjections into M1 demonstrated that l-DOPA-induced dyskinesia was reduced by M1 infusion of a D1 antagonist, an AMPA antagonist, or a GABAA agonist. Overall, the present study demonstrates that l-DOPA-induced dyskinesia is associated with increased M1 inhibition and that exogenously enhancing M1 inhibition may attenuate dyskinesia, findings that are in agreement with functional imaging and transcranial magnetic stimulation studies in human Parkinson's disease patients. Together, our study suggests that increasing M1 inhibitory tone is an endogenous compensatory response designed to limit dyskinesia severity and that potentiating this response is a viable therapeutic strategy. SIGNIFICANCE STATEMENT: Most Parkinson's disease patients will receive l-DOPA and eventually develop hyperkinetic involuntary movements termed dyskinesia. Such symptoms can be as debilitating as the disease itself. Although dyskinesia is associated with dynamic changes in primary motor cortex physiology, to date, there are no published studies investigating in vivo neurotransmitter release in M1 during dyskinesia. In parkinsonian rats, l-DOPA administration reduced M1 glutamate efflux and enhanced GABA efflux, coincident with the emergence of dyskinetic behaviors. Dyskinesia could be reduced by local M1 modulation of D1, AMPA, and GABAA receptors, providing preclinical support for the notion that exogenously blunting M1 signaling (pharmacologically or with cortical stimulation) is a therapeutic approach to the treatment of debilitating dyskinesias.
Assuntos
Ácido Glutâmico/metabolismo , Córtex Motor/metabolismo , Transdução de Sinais/efeitos dos fármacos , Discinesia Tardia/patologia , Ácido gama-Aminobutírico/metabolismo , Animais , Antiparkinsonianos/efeitos adversos , Corpo Estriado/metabolismo , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Fármacos Atuantes sobre Aminoácidos Excitatórios/farmacologia , GABAérgicos/farmacologia , Levodopa/efeitos adversos , Masculino , Córtex Motor/efeitos dos fármacos , Movimento/efeitos dos fármacos , Oxidopamina/toxicidade , Transtornos Parkinsonianos/induzido quimicamente , Transtornos Parkinsonianos/tratamento farmacológico , Desempenho Psicomotor/efeitos dos fármacos , Desempenho Psicomotor/fisiologia , Ratos , Ratos Sprague-Dawley , Simpatolíticos/toxicidade , Discinesia Tardia/induzido quimicamenteRESUMO
IMPORTANCE: Ventilator-induced lung injury may arise from heterogeneous lung microanatomy, whereby some alveoli remain collapsed throughout the breath cycle while their more compliant or surfactant-replete neighbors become overdistended, and this is called dynamic alveolar heterogeneity. OBJECTIVE: To determine how dynamic alveolar heterogeneity is influenced by 2 modes of mechanical ventilation: low tidal-volume ventilation (LTVV) and airway pressure release ventilation (APRV), using in vivo microscopy to directly measure alveolar size distributions. DESIGN, SETTING, AND PARTICIPANTS: In a randomized, nonblinded laboratory animal study conducted between January 2013 and December 2014, 14 rats (450-500 g in size) were randomized to a control group with uninjured lungs (n = 4) and 2 experimental groups with surfactant deactivation induced by polysorbate lavage: the LTVV group (n = 5) and the APRV group (n = 5). For all groups, a thoracotomy and in vivo microscopy were performed. Following lung injury induced by polysorbate lavage, the LTVV group was ventilated with a tidal volume of 6 mL/kg and progressively higher positive end-expiratory pressure (PEEP) (5, 10, 16, 20, and 24 cm H2O). Following lung injury induced by polysorbate lavage, the APRV group was ventilated with a progressively shorter time at low pressure, which increased the ratio of the end-expiratory flow rate (EEFR) to the peak expiratory flow rate (PEFR; from 10% to 25% to 50% to 75%). MAIN OUTCOMES AND MEASURES: Alveolar areas were quantified (using PEEP and EEFR to PEFR ratio) to determine dynamic heterogeneity. RESULTS: Following lung injury induced by polysorbate lavage, a higher PEEP (20-24 cm H2O) with LTVV resulted in alveolar occupancy (reported as percentage of total frame area) at inspiration (39.9%-42.2%) and expiration (35.9%-38.7%) similar to that in the control group (inspiration 53.3%; expiration 50.3%; P > .01). Likewise, APRV with an increased EEFR to PEFR ratio (50%-75%) resulted in alveolar occupancy at inspiration (46.7%-47.9%) and expiration (40.2%-46.6%) similar to that in the control group (P > .01). At inspiration, the distribution of the alveolar area of the control group was similar to that of the APRV group (P > .01) (but not to that of the LTVV group [P < .01]). A lower PEEP (5-10 cm H2O) and a decreased EEFR to PEFR ratio (≤50%) demonstrated dynamic heterogeneity between inspiration and expiration (P < .01 for both) with a greater percentage of large alveoli at expiration. Dynamic alveolar homogeneity between inspiration and expiration occurred with higher PEEP (16-24 cm H2O) (P > .01) and an increased EEFR to PEFR ratio (75%) (P > .01). CONCLUSIONS AND RELEVANCE: Increasing PEEP during LTVV increased alveolar recruitment and dynamic homogeneity but had a significantly different alveolar size distribution compared with the control group. By comparison, reducing the time at low pressure (EEFR to PEFR ratio of 75%) in the APRV group provided dynamic homogeneity and a closer approximation of the dynamics observed in the control group.
Assuntos
Pressão Positiva Contínua nas Vias Aéreas/métodos , Respiração com Pressão Positiva/métodos , Alvéolos Pulmonares/patologia , Lesão Pulmonar Induzida por Ventilação Mecânica/patologia , Animais , Fluxo Expiratório Forçado , Microscopia , Modelos Animais , Distribuição Aleatória , Ratos Sprague-Dawley , ToracotomiaRESUMO
The acute phase response (APR) to infection can alter blood-based indicators of micronutrient status. Data from a 3-mo randomized, controlled feeding trial in rural Zambian children (n = 181, aged 3-5 y) were used to determine the impact of the APR on indicators of vitamin A and iron status using baseline and final blood samples. Concentrations of acute phase proteins were categorized as raised C-reactive protein (CRP; >5 and >10 mg/L) only, both raised CRP and α1-acid glycoprotein (AGP; >1.2 g/L), raised AGP only, and neither CRP nor AGP raised to identify the respective stages of infection: incubation, early convalescence, convalescence, and healthy state. Data were insufficient to examine the incubation stage of infection. A CRP concentration of >5 mg/L was an effective elevation cutoff point in this population to show impact on micronutrient markers. Time did not affect hemoglobin, serum ferritin, or serum retinol concentrations (P > 0.05). During early convalescence, hemoglobin decreased (14-16%; P ≤ 0.05), serum ferritin increased (279-356%; P ≤ 0.05), and serum retinol decreased (20-30%; P ≤ 0.05). Serum retinol concentrations did not change during convalescence; however, hemoglobin remained depressed (4-9%) and serum ferritin was elevated (67-132%) (both P ≤ 0.05). Modified relative dose response values were unaffected by the APR (P > 0.05) but increased between time points (16%; P ≤ 0.05), indicating a decrease in liver vitamin A reserves on the background of a semiannual vitamin A supplementation program. The observed prevalence of anemia and vitamin A deficiency assessed by serum retinol concentration was higher during the APR (P ≤ 0.05). It is important to consider the impact of infection on dietary interventions and to adjust for acute phase proteins when assessing iron status or vitamin A status by serum retinol concentration alone in children.
Assuntos
Reação de Fase Aguda/sangue , Ferro da Dieta/sangue , Micronutrientes/sangue , Vitamina A/sangue , Anemia Ferropriva/sangue , Biomarcadores/sangue , Proteína C-Reativa/metabolismo , Pré-Escolar , Ferritinas/sangue , Hemoglobinas/metabolismo , Humanos , Orosomucoide/metabolismo , Prevalência , População Rural , Deficiência de Vitamina A/sangue , ZâmbiaRESUMO
BACKGROUND: Vitamin A deficiency is associated with poor health outcomes related to reproduction, growth, vision, and immunity. Biofortification of staple crops is a novel strategy for combating vitamin A deficiency in high-risk populations where staple food intakes are high. African populations are proposed beneficiaries of maize (Zea mays) biofortified with provitamin A carotenoids, often called "orange maize" because of its distinctive deep yellow-orange kernels. The color facilitates ready recognition but presents a cultural challenge to maize-consuming populations, including those in much of Africa, who traditionally eat white varieties. OBJECTIVE: This study explores the intake patterns of, as well as adaptation to, traditional foods made with provitamin A-biofortified maize compared with white maize in rural Zambian children 3 to 5 years of age (n = 189) during a 3-month feeding trial. METHODS: The subjects were fed a breakfast of maize porridge (sweet mush), a lunch of maize nshima (stiff mush) with various side dishes, and an afternoon snack based on a 6-day rotating menu. The trial was conducted in 2010. The orange maize used in the trial came from three different sources. O1 maize was from the 2009 harvest and was stored in a freezer until use in 2010. O2 maize was also from the 2009 harvest and was stored in a cold room until 2010. O3 ("fresh") maize was from the 2010 harvest and was fed immediately after harvest in week 9 of the study and then stored in a freezer until milling for the final four weeks. RESULTS: Consumption of menu items, except snacks, was influenced by week (p < .0084). The intakes of porridge and nshima made with orange maize equaled those of porridge and nshima made with white maize from week 2 onward. The intakes of porridge and nshima prepared from O1 and O2 did not differ, but intakes became significantly higher when meals made from O3 were introduced (p < .014 for porridge and p < or = .013 for nshima). CONCLUSIONS: These results demonstrate quick adaptation to orange maize, a preference for recently harvested maize, and an optimistic outlook for similar adaptation patterns in other biofortified-maize target countries.
Assuntos
Carotenoides/metabolismo , Dieta , Preferências Alimentares , Alimentos Geneticamente Modificados , Pigmentos Biológicos/metabolismo , Sementes/metabolismo , Zea mays/metabolismo , Carotenoides/administração & dosagem , Comportamento Infantil/etnologia , Pré-Escolar , Serviços de Saúde Comunitária , Condimentos/análise , Dieta/etnologia , Grão Comestível/química , Fast Foods/análise , Manipulação de Alimentos , Preferências Alimentares/etnologia , Serviços de Alimentação , Promoção da Saúde , Humanos , Saúde da População Rural , Sementes/química , Deficiência de Vitamina A/prevenção & controle , Zâmbia , Zea mays/químicaRESUMO
Africa shares a unique relationship with maize (Zea mays). After its introduction from New World explorers, maize was quickly adopted as the cornerstone of local cuisine, especially in sub-Saharan countries. Although maize provides macro- and micronutrients required for humans, it lacks adequate amounts of the essential amino acids lysine and tryptophan. For those consuming >50% of their daily energy from maize, pandemic protein malnutrition may exist. Severe protein and energy malnutrition increases susceptibility to life-threatening diseases such as tuberculosis and gastroenteritis. A nutritionally superior maize cultivar named quality protein maize (QPM) represents nearly one-half century of research dedicated to malnutrition eradication. Compared with traditional maize types, QPM has twice the amount of lysine and tryptophan, as well as protein bioavailability that rivals milk casein. Animal and human studies suggest that substituting QPM for common maize results in improved health. However, QPM's practical contribution to maize-subsisting populations remains unresolved. Herein, total protein and essential amino acid requirements recommended by the WHO and the Institute of Medicine were applied to estimate QPM target intake levels for young children and adults, and these were compared with mean daily maize intakes by African country. The comparisons revealed that ~100 g QPM is required for children to maintain adequacy of lysine, the most limiting amino acid, and nearly 500 g is required for adults. This represents a 40% reduction in maize intake relative to common maize to meet protein requirements. The importance of maize in Africa underlines the potential for QPM to assist in closing the protein inadequacy gap.
Assuntos
Dieta/normas , Proteínas Alimentares/metabolismo , Abastecimento de Alimentos , Disparidades nos Níveis de Saúde , Necessidades Nutricionais , Desnutrição Proteico-Calórica/prevenção & controle , Zea mays , África , Animais , Proteínas Alimentares/normas , Ingestão de Energia , Disparidades em Assistência à Saúde , Humanos , Lisina/administração & dosagem , Lisina/metabolismo , Triptofano/administração & dosagem , Triptofano/metabolismo , Populações Vulneráveis , Zea mays/metabolismoRESUMO
The maize plant (Zea mays), characterized by an erect green stalk, is one of the 3 great grain crops of the world. Its kernels, like other seeds, are storage organs that contain essential components for plant growth and reproduction. Many of these kernel constituents, including starch, protein, and some micronutrients, are also required for human health. For this reason, and others, maize has become highly integrated into global agriculture, human diet, and cultural traditions. The nutritional quality and integrity of maize kernels are influenced by many factors including genetic background, environment, and kernel processing. Cooking procedures, including nixtamalization and fermentation, can increase accessibility of micronutrients such as niacin. However, man cannot live on maize alone. For one-third of the world's population, namely in sub-Saharan Africa, Southeast Asia, and Latin America, humans subsist on maize as a staple food but malnutrition pervades. Strategies to further improve kernel macronutrient and micronutrient quality and quantities are under intense investigation. The 2 most common routes to enhance grain nutritional value are exogenous and endogenous fortification. Although exogenous fortification, such as addition of multivitamin premixes to maize flour, has been successful, endogenous fortification, also known as "biofortification," may provide a more sustainable and practical solution for chronically undernourished communities. Recent accomplishments, such as low-phytate, high-lysine, and multivitamin maize varieties, have been created using novel genetic and agronomic approaches. Investigational studies related to biofortified maize are currently underway to determine nutrient absorption and efficacy related to human health improvement.