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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
121

Impaired Spatial Navigation in Adult Female but Not Adult Male Rats Exposed to Alcohol During the Brain Growth Spurt

Kelly, Sandra J., Goodlett, Charles R., Hulsether, Sara A., West, James R. 01 January 1988 (has links)
Two groups of male and female rats were given the same dose of alcohol using an artificial rearing procedure on postnatal days 4-10. One group received the alcohol in a condensed manner each day which caused cyclic blood alcohol concentrations (BACs) with high peaks. A second group received the alcohol in a uniform manner over each day which resulted in moderate, stable BACs. Two control groups consisted of male and female rats artificially reared but not exposed to alcohol and rats reared normally by dams. All rats were raised to 90 days of age and then tested for spatial navigation ability in the Morris water maze, which involved locating a hidden underwater platform using distal extramaze cues. Neither the alcohol treatments nor the artificial rearing had any effects on performance of adult male rats relative to suckle controls in this task. In contrast, the condensed alcohol exposure but not the uniform alcohol exposure resulted in detrimental performance in the Morris water maze by adult female rats. When the ability to locate and escape onto a visible platform was examined, there were no differences between the female groups given condensed alcohol exposure or artificially reared on milk solution alone. Thus, exposure to high BACs during the brain growth spurt has a lasting and selective detrimental effect on spatial navigation learning in adult female but not adult male rats.
122

Organization of the Commissural Projection to the Dentate Gyrus Is Unaltered by Heavy Ethanol Exposure During Gestation

Dewey, Stephen L., West, James R. 01 January 1985 (has links)
The anterograde horseradish peroxidase method was used to determine if prenatal exposure to ethanol affected the development of the characteristic afferent lamination pattern of the commissural projection to the dentate gyrus. Mean ethanol consumption for the ethanol-consuming dams was 12.7 g/kg ± 0.3 g per day. Adult offspring of rats that consumed a liquid diet containing 35% ethanol-derived calories during days 1-21 of gestation, and both pair-fed and normal controls were examined. Brain weights and volumes of the ethanol and pair-fed control rats did not differ significantly from normal controls. However, body weights of ethanol-exposed rats were significantly reduced compared to normal controls. Computer-assisted image analysis of the HRP-labeling revealed that in spite of the heavy ethanol exposure there was no evidence of alterations in the spatial distribution of the commissural terminal field.
123

Alcohol Use in Pregnancy: Insights in Screening and Intervention for the Clinician

Jones, Theodore B., Bailey, Beth A., Sokol, Robert J. 01 March 2013 (has links)
Alcohol consumption during pregnancy remains a common occurrence and is associated with a multitude of adverse birth and long-term outcomes. Binge drinking in particular is shown to be particularly harmful to the developing fetus. Effects include full fetal alcohol syndrome, with characteristic facial dysmorphology, growth restriction, and developmental to delays. Exposed children may also have partial fetal alcohol syndrome, alcohol-related birth defects, and alcohol-related neurodevelopmental disorders. These effects are preventable, and efforts must begin with accurate identification of women who consume alcohol during pregnancy. Several screening tools have been developed and validated for use in prenatal care settings, and the most recently proposed brief and easy to use T-ACER3 has demonstrated high sensitivity and specificity in both identifying risk drinking during pregnancy and predicting long-term neurobehavioral outcomes in exposed children. Once identified, effective interventions are available for use with pregnant women consuming alcohol. Brief interventions, which can be delivered by a health professional and involve motivational interviewing, have been demonstrated to significantly reduce alcohol consumption during pregnancy. These approaches, recommended by American College of Obstetricians and Gynecologist (ACOG), help move patients toward increased readiness to positively change their drinking behavior. Ultimately, all prenatal care providers should routinely screen all patients for alcohol use using validated tools, and where appropriate, should offer intervention.
124

Alcohol Use in Pregnancy: Insights in Screening and Intervention for the Clinician

Jones, Theodore B., Bailey, Beth A., Sokol, Robert J. 01 March 2013 (has links)
Alcohol consumption during pregnancy remains a common occurrence and is associated with a multitude of adverse birth and long-term outcomes. Binge drinking in particular is shown to be particularly harmful to the developing fetus. Effects include full fetal alcohol syndrome, with characteristic facial dysmorphology, growth restriction, and developmental to delays. Exposed children may also have partial fetal alcohol syndrome, alcohol-related birth defects, and alcohol-related neurodevelopmental disorders. These effects are preventable, and efforts must begin with accurate identification of women who consume alcohol during pregnancy. Several screening tools have been developed and validated for use in prenatal care settings, and the most recently proposed brief and easy to use T-ACER3 has demonstrated high sensitivity and specificity in both identifying risk drinking during pregnancy and predicting long-term neurobehavioral outcomes in exposed children. Once identified, effective interventions are available for use with pregnant women consuming alcohol. Brief interventions, which can be delivered by a health professional and involve motivational interviewing, have been demonstrated to significantly reduce alcohol consumption during pregnancy. These approaches, recommended by American College of Obstetricians and Gynecologist (ACOG), help move patients toward increased readiness to positively change their drinking behavior. Ultimately, all prenatal care providers should routinely screen all patients for alcohol use using validated tools, and where appropriate, should offer intervention.
125

Recognized Spontaneous Abortion in Mid-Pregnancy and Patterns of Pregnancy Alcohol Use

Chiodo, Lisa M., Bailey, Beth A., Sokol, Robert J., Janisse, James, Delaney-Black, Virginia, Hannigan, John H. 01 May 2012 (has links)
Alcohol consumption during pregnancy is one potential risk factor for spontaneous abortion (SAb). Prior research suggested that heavy drinking during pregnancy was associated with significantly increased rates of SAb, but results for lower levels of drinking have been inconsistent. We examined the association between different levels and patterns of prenatal alcohol consumption and SAb in a high-risk inner-city sample. We hypothesized that higher levels, binge patterns, and more frequent drinking would be associated with increased rates of SAb. The quantity and frequency of self-reported peri-conceptional and repeated in-pregnancy maternal drinking volumes per beverage type were assessed with semi-structured interviews in a prospective subsample of 302 African-American mothers. Relations between various measures of prenatal alcohol exposure and SAb were assessed using logistic regression. After controlling for various potential confounders, there was a significant positive relation between average absolute alcohol use per day across pregnancy and SAb. Greater frequency of drinking episodes also predicted SAb: an average of even one day of drinking per week across pregnancy was associated with an increase in the incidence of SAb. However, contrary to our hypothesis, neither the amount of alcohol drunk per drinking day nor a measure of binge drinking was significantly related to SAb after controlling for confounders. Differences in when women who drank at risk levels initiated antenatal care may have under-estimated the impact of alcohol on SAb in this low-SES urban African-American sample. Some drinking measures averaged across pregnancy may have under-estimated consumption and overestimated risk of SAb, but other risk drinking measures that avoid this limitation show similar relations to SAb. Identifying fetal risk drinking in pregnant women is critical to increasing the effectiveness of interventions that reduce risk level alcohol consumption and protect from pregnancy loss.
126

The Preventive Effect of Oral EGCG in a Fetal Alcohol Spectrum Disorder Mouse Model

Long, Ling, Li, Yi, Wang, Yi D., He, Qing Y., Li, Mei, Cai, Xiao D., Peng, Kou, Li, Xiang P., Xie, Dan, Wen, Yan Ling, Yin, Deling, Peng, Ying 01 November 2010 (has links)
Background: Fetal alcohol spectrum disorder (FASD) is a challenging public health problem. Previous studies have found an association between FASD and oxidative stress. In the present study, we assessed the role of oxidative stress in ethanol-induced embryonic damage and the effect of (-)-epigallocatechin-3-gallate (EGCG), a powerful antioxidant extracted from green tea, on the development of FASD in a murine model.Methods: Pregnant female mice were given intraperitoneal ethanol (25%, 0.005 to 0.02 ml/g) on gestational day 8 (G8) to establish the FASD model. On G10.25, mice were sacrificed and embryos were collected and photographed to determine head length (HL), head width (HW), and crown rump length (CRL). For mice given EGCG, administration was through a feeding tube on G7 and G8 (dose: 200, 300, or 400 mg/kg/d, the total amount for a day was divided into 2 equal portions). G10.25 embryos were evaluated morphologically. Brain tissues of G9.25 embryos were used for RT-PCR and western blotting of neural marker genes and proteins and detection of oxidative stress indicators.Results: Administration of ethanol to pregnant mice on G8 led to the retardation of embryonic growth and down-regulation of neural marker genes. In addition, administration of ethanol (0.02 ml/g) led to the elevation of oxidative stress indicators [hydrogen peroxide (H2O2) and malondialdehyde (MDA)]. Administration of EGCG on G7 and G8 along with ethanol on G8 ameliorated the ethanol-induced growth retardation. Mice given EGCG (400 mg/kg/d) along with ethanol had embryo sizes and neural marker genes expression similar to the normal controls. Furthermore, EGCG (400 mg/kg on G7 and G8) inhibited the increase in H2O2 and MDA.Conclusions: In a murine model, oxidative stress appears to play an important role in ethanol-induced embryonic growth retardation. EGCG can prevent some of the embryonic injuries caused by ethanol.
127

Pregnancy and Alcohol Use: Evidence and Recommendations for Prenatal Care

Bailey, Beth, Sokol, Robert J. 01 June 2008 (has links)
Pregnancy alcohol consumption has been linked to poor birth outcomes and long-term developmental problems. Despite this, a significant number of women drink during pregnancy. Although most prenatal care providers are asking women about alcohol use, validated screening tools are infrequently employed. Research has demonstrated that currently available screening methods and intervention techniques are effective in identifying and reducing pregnancy drinking. Implementing universal screening and appropriate intervention for pregnancy alcohol use should be a priority for prenatal care providers, as these efforts could substantially improve pregnancy, birth, and longer term developmental outcomes for those affected.
128

Is Prematurity a Part of Fetal Alcohol Spectrum Disorder?

Bailey, Beth, Sokol, Robert J. 01 March 2008 (has links)
Since fetal alcohol syndrome was first reported, studies have demonstrated a range of perinatal/developmental abnormalities that fall under the umbrella term fetal alcohol spectrum disorders. Of these, low birth weight in exposed children is among the most commonly observed and widely accepted. However, in the past, assertion of an association between prenatal alcohol exposure and preterm birth was controversial. Methodological difficulties may have contributed to failure to consistently detect such a relationship. However, new evidence suggests that pregnancy drinking may be a major contributor to extreme, but not mild prematurity. Extreme prematurity is a major cause of severe perinatal morbidity and mortality. If recent findings are confirmed, it suggests that extreme prematurity might be reduced by eliminating prenatal alcohol exposure.
129

Tissue Parameter Mapping in Children with Fetal Alcohol Spectrum Disorders

Fourie, Marilize 14 September 2020 (has links)
Background: Fetal alcohol spectrum disorders (FASD), which are caused by prenatal alcohol exposure (PAE), affects people around the world. Certain communities in South Africa have among the highest reported incidences of fetal alcohol syndrome (FAS) in the world. Although PAE-related brain alterations have been widely documented, the mechanisms whereby alcohol affects the brain are not clearly understood. MRI relaxation parameters T1, T2, T2* and proton density (PD), are basic tissue properties that reflect the underlying biology. The present study aims to advance our understanding of how PAE alters the microstructural properties of tissue by examining PAE-related changes in these tissue parameters in adolescents with FASD. Methods: The final sample used in this study consisted of 53 children from a previously studied longitudinal cohort (Jacobson et al., 2008) and 12 additionally recruited subjects. Of the 65 participants, 18 were diagnosed with FAS or partial FAS (PFAS) and made up the FAS/PFAS group, 18 were diagnosed as heavily exposed non-syndromal (HE) and 29 were age matched controls. Subjects were scanned at the Cape Universities Body Imaging Centre (CUBIC) located at Groote Schuur Hospital on a 3T Siemens Skyra MRI. Structural images were obtained using the MEMPRAGE sequence. From these images T1, T2, T2* and PD parameter maps were constructed and segmented into 43 regions of interest (ROI) using Freesurfer, FSL and AFNI. Linear regression analyses were used to analyse group differences as well as correlations between parameter values and the amount of alcohol the mother consumed during pregnancy. Results: Significant T1 differences were found in the caudate, cerebellar cortex, hippocampus, accumbens, putamen, choroid plexus, ventral diencephalon (DC), right vessel and ventricles. Significant T2 differences were found in the caudate, brain stem, corpus callosum (CC), amygdala, cerebral cortex, choroid plexus, vessels and ventricles. Significant T2* differences were found in the cerebellar cortex, optic chiasm and ventricles. Significant PD differences were found in the hippocampus and left lateral ventricle. The exploratory nature of this study resulted in none of the results surviving FDR correction for multiple comparisons. Conclusions: Overall, our findings point to regional PAE-related increases in water content and cellular and molecular changes in underlying tissue of the anatomical structure. Exceptions were the right cerebral cortex, brain stem, hippocampus, amygdala and ventral diencephalon where our findings point to less free water and increased cell density, and cerebellar cortex where simultaneous reductions in T1 and T2* suggest the possibility of increased iron content. In highly myelinated white matter structures, such as the CC and optic chiasm, our results point to PAErelated demyelination, and possibly increased iron. These findings extend previous knowledge of effects of PAE and demonstrate that tissues are affected at a microstructural level.
130

Magnetic resonance spectroscopy quality assessment at CUBIC and application to the study of the cerebellar deep nuclei in children with fetal alcohol spectrum disorder

Du Plessis, Lindie January 2010 (has links)
Includes bibliographical references (leaves 73-79). / In vivo magnetic resonance spectroscopy (MRS) is an imaging technique that allows the chemical study of human tissue non-invasively. The method holds great promise as a diagnostic tool once its reliability has been established. Inter-scanner variability has, however, hampered this from happening as results cannot easily be compared if acquired on different scanners. In this study a phantom was constructed to determine the localisation efficiency of the 3 T Siemens Allegra MRI scanner located at the Cape Universities Brain Imaging Centre (CUBIC). Sufficient localisation is the key to acquiring useful spectroscopic data as only the signal from a small volume of interest (VOI) is typically acquired. The phantom consisted of a Perspex cube located inside a larger Perspex sphere. Solutions of the cerebral metabolites N-acetyl aspartate (NAA) and choline (Cho) were placed in the inner cube and outer sphere respectively. The phantom was scanned at a range of voxel sizes and echo times in order to determine parameters that typically indicate the performance of the scanner in question. The resultant full width at half maximum (FWHM) and signal to noise ratio (SNR) values indicated that optimal results were obtained for a voxel with dimensions 20 x 20 x 20 mm3. The selection efficiency could not be measured due to limitations in the scanner, but two other performance parameters ' extra volume suppression (EVS) and contamination ' could be determined. The EVS showed that the scanner was able to eliminate the entire background signal from the out-of-voxel region when voxel sizes with dimensions (20 mm)3 and (30 mm)3 were used. This performance decreased to 96.2% for a voxel size of (50 mm)3. The contamination indicated that the unwanted signal, weighted by the respective proton densities of the chemicals, ranged from 12% in the (20 mm)3 voxel to 24% in the (50 mm)3 voxel. These ranges are well within acceptable limits for proton MRS. Analysis of the water suppression achieved in the scanner showed an efficiency of 98.84%, which is acceptable for proton spectroscopy. It was also found that manual iv shimming of the scanner improved the spectra obtained, as compared to the automated shimming performed by the scanner. The second objective of the study was to quantify absolute metabolite concentrations in the familiar SI units of mM as results were previously mostly expressed as metabolite ratios. The LCModel software was used to assess two methods of determining absolute metabolite concentrations and the procedure using water scaling consistently showed superior performance to a method using a calibration factor. The method employing water scaling was then applied to a study of fetal alcohol spectrum disorder (FASD) where the deep cerebellar nuclei of children with FASD and a control group were scanned. The cerebellar nuclei were of interest as children with FASD show a remarkably consistent deficit in eye blink conditioning (EBC). The cerebellar deep nuclei is known to play a critical role in the EBC response. The results show significant decreases in the myo-inositol (mI) and total choline (tCho) concentrations of children with FASD in the deep cerebellar nuclei compared to control children. The FAS/PFAS subjects have a mean mI concentration of 4.6 mM as compared to a mean of 5.3 mM in the controls. A Pearson correlation showed that there was a significant relationship between decreasing mI concentrations with increasing prenatal alcohol exposure. The mean tCho concentrations are 1.3 mM for FAS/PFAS and 1.5 mM for the controls. There was no significant differences between the heavily exposed group and either the FAS/PFAS or the control subjects for either metabolite. The decreased mI and tCho concentrations may indicate deficient calcium signalling or decreased cell membrane integrity ' both of which can explain the compromised cerebellar learning in FASD subjects.

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