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Mekibib Altaye

Publications and source records attributed to Mekibib Altaye.

14 recordsLinked to original sources
PubMed2006

A longitudinal functional magnetic resonance imaging study of language development in children 5 to 11 years old.

OBJECTIVE: Language skills continue to develop rapidly in children during the school-age years, and the "snapshot" view of the neural substrates of language provided by current neuroimaging studies cannot capture the dynamic changes associated with brain development. The aim of this study was to conduct a 5-year longitudinal investigation of language development using functional magnetic resonance imaging in healthy children. METHODS: Thirty subjects enrolled at ages 5, 6, or 7 were examined annually for 5 years using a 3-Tesla magnetic resonance imaging scanner and a verb generation task. Data analysis was conducted based on a general linear model that was modified to investigate developmental changes whereas minimizing the potential for missing data. RESULTS: With increasing age, there is progressive participation in language processing by the inferior/middle frontal, middle temporal, and angular gyri of the left hemisphere and the lingual and inferior temporal gyri of the right hemisphere and regression of participation of the left posterior insula/extrastriate cortex, left superior frontal and right anterior cingulate gyri, and left thalamus. CONCLUSION: The age-related changes observed in this study provide evidence of increased neuroplasticity of language in this age group and may have implications for further investigations of normal and aberrant language development.

Algorithms↗
PubMed2006

Adiponectin is present in human milk and is associated with maternal factors.

BACKGROUND: Previous studies have shown that human milk has a role in the gastrointestinal, neural, and immune development of neonates. If present in milk, adiponectin would be a promising candidate for influencing infant development, given its metabolic functions. OBJECTIVES: Our objectives were to determine whether adiponectin is present in human milk and to characterize maternal factors associated with potential variation in milk adiponectin concentrations. DESIGN: We quantified adiponectin concentrations in human milk samples from donors to the Cincinnati Children's Research Human Milk Bank and randomly selected participants in a cohort study in Mexico City funded by the National Institutes of Health. Using cross-sectional and longitudinal data, we examined milk adiponectin concentrations in relation to lactation duration, maternal body mass index (BMI; in kg/m(2)), and ethnicity. RESULTS: Adiponectin was detected in human skim milk (range: 4.2-87.9 ng/mL). In cross-sectional and longitudinal analyses, duration of lactation was negatively associated with milk adiponectin concentrations (beta = -0.059 +/- 0.024 and -0.059 +/- 0.007, respectively; P < 0.02 for both). Maternal postpregnancy BMI was positively associated with milk adiponectin concentrations (beta = 0.08 +/- 0.02, P < 0.0001; longitudinal analysis). Mexican mothers had lower median milk adiponectin concentrations at 1 mo than did the non-Hispanic white subjects from Cincinnati (11.5 and 19.8 ng/mL; P = 0.003). CONCLUSIONS: Adiponectin is present in human milk and its concentrations are associated with duration of lactation, maternal adiposity, and ethnicity. Given the importance of adiponectin in inflammation, insulin sensitivity, and fatty acid metabolism, future studies should examine milk adiponectin's role in infant metabolic development.

Adiponectin↗
PubMed2006

Risk of infant anemia is associated with exclusive breast-feeding and maternal anemia in a Mexican cohort.

The WHO recommends exclusive breast-feeding (EBF) for the first 6 mo of life to decrease the burden of infectious disease. However, some are concerned about the effect of EBF >6 mo on iron status of children in developing countries in which anemia is prevalent. This study examines the risk of anemia in relation to the duration of EBF and maternal anemia in a birth cohort studied between March 1998 and April 2003. All infant birth weights were >or=2.2 kg. All mothers received home-based peer counseling to promote EBF. Infant feeding data were collected weekly. Nurses measured hemoglobin (Hb) values every 3 mo. Hb was measured in 183 infants at 9 mo of age. Anemia at 9 mo was defined as a Hb value <100 g/L. EBF was defined by WHO criteria and ranged in duration from 0 to 31 wk. At 9 mo, Hb (mean +/- SEM) was 114 +/- 0.9 g/L; 23 children (12.5%) had Hb levels <100 g/L. EBF >6 mo, but not EBF 4-6 mo, was associated with increased risk of infant anemia compared with EBF <4 mo (odds ratio=18.4, 95% CI=1.9, 174.0). Maternal anemia was independently (P=0.03) associated with a 3-fold increased risk of infant anemia. These associations were not explained by confounding with other maternal or infant factors. By linear regression, a lower infant Hb at 9 mo was associated with increased EBF duration among mothers who had a history of anemia (beta=-0.07, P=0.003), but not among mothers with no history of anemia. Infants who are exclusively breast-fed for >6 mo in developing countries may be at increased risk of anemia, especially among mothers with a poor iron status; greater attention to this issue is warranted.

Anemia↗
PubMed2006

The impact of early childhood lead exposure on brain organization: a functional magnetic resonance imaging study of language function.

OBJECTIVES: The purpose of this work was to assess the long-term impact of childhood lead exposure on the neurosubstrate of language function and brain organization. METHODS: Young adults from the Cincinnati Lead Study were recruited to undergo functional magnetic resonance image scanning while performing a verb generation task. These subjects have been followed from birth through early childhood with extensive documentation of lead exposure, neuropsychology, and behavior. Forty-two subjects provided useful imaging data. The locale, strength, and the correlation between brain language activation and childhood blood lead concentration were studied. RESULTS: After adjusting for potential confounders, the activation in left frontal cortex, adjacent to Broca's area, and left middle temporal gyrus, including Wernicke's area, were found to be significantly associated with diminished activation in subjects with higher mean childhood blood lead levels, whereas the compensatory activation in the right hemisphere homolog of Wernicke's area was enhanced in subjects with higher blood lead levels. CONCLUSION: This study indicates that childhood lead exposure has a significant and persistent impact on brain reorganization associated with language function.

Adult↗
PubMed2005

Elevated cytokine levels in children with autism spectrum disorder.

UNLABELLED: This study compared production of IL-2, IFN-gamma, IL-4, IL-13, IL-5 and IL-10 in peripheral blood mononuclear cells from 20 children with autism spectrum disorder to those from matched controls. Levels of all Th2 cytokines were significantly higher in cases after incubation in media alone, but the IFN-gamma/IL-13 ratio was not significantly different between cases and controls. Cases had significantly higher IL-13/IL-10 and IFN-gamma/IL-10 than controls. CONCLUSION: Children with ASD had increased activation of both Th2 and Th1 arms of the adaptive immune response, with a Th2 predominance, and without the compensatory increase in the regulatory cytokine IL-10.

Autistic Disorder↗
PubMed2005

Middle cerebral artery peak systolic velocity: technique and variability.

OBJECTIVE: Assessment of the middle cerebral artery (MCA) peak systolic velocity (PSV) can accurately diagnose fetal anemia and has decreased the number of invasive procedures, such as amniocentesis and cordocentesis. The objective of this investigation was to evaluate the intraobserver and interobserver variability as a measure of reproducibility of MCA PSV. The technique of correctly sampling this vessel is described. METHODS: The study population included 30 appropriate-for-gestational-age fetuses. In each fetus, MCA PSV was determined proximal to the transducer at 3 different locations: 2 mm after its origin from the internal carotid artery, at the midlength between its origin and division, and at its division. The peak systolic velocity was also determined at the contralateral MCA 2 mm after its origin. With each measurement (obtained at 2 different institutions), care was taken to ensure that the ultrasound beam was parallel to the artery for its entire length. The reliability of an angle corrector was also assessed. The intraobserver and interobserver reliabilities were determined from the appropriate version of the intraclass correlation. RESULTS: Gestational age at study entry ranged from 14 to 37.5 weeks (median, 23.6 weeks). The proximal MCA, 2 mm after its origin from the internal carotid artery, had the best intraobserver and interobserver variability in both institutions. (Intraclass correlation ranged from 0.98 to 0.99.) CONCLUSIONS: Our data indicate that fetal MCA PSV is optimally measured soon after the MCA's origin from the internal carotid artery. Given the importance of clinical decision making based on this measurement, sonographers and sonologists interested in measuring MCA PSV should test their variability after a suitable period of training.

Analysis of Variance↗
PubMed2004

Human milk oligosaccharides are associated with protection against diarrhea in breast-fed infants.

OBJECTIVE: To determine the association between maternal milk levels of 2-linked fucosylated oligosaccharide and prevention of diarrhea as a result of Campylobacter, caliciviruses, and diarrhea of all causes in breast-fed infants. STUDY DESIGN: Data and banked samples were analyzed from 93 breast-feeding mother-infant pairs who were prospectively studied during 1988-1991 from birth to 2 years with infant feeding and diarrhea data collected weekly; diarrhea was diagnosed by a study physician. Milk samples obtained 1 to 5 weeks postpartum were analyzed for oligosaccharide content. Data were analyzed by Poisson regression. RESULTS: Total 2-linked fucosyloligosaccharide in maternal milk ranged from 0.8 to 20.8 mmol/L (50%-92% of milk oligosaccharide). Moderate-to-severe diarrhea of all causes (n=77 cases) occurred less often (P=.001) in infants whose milk contained high levels of total 2-linked fucosyloligosaccharide as a percent of milk oligosaccharide. Campylobacter diarrhea (n=31 cases) occurred less often (P=.004) in infants whose mother's milk contained high levels of 2'-FL, a specific 2-linked fucosyloligosaccharide, and calicivirus diarrhea (n=16 cases) occurred less often (P=.012) in infants whose mother's milk contained high levels of lacto-N-difucohexaose (LDFH-I), another 2-linked fucosyloligosaccharide. CONCLUSION: This study provides novel evidence suggesting that human milk oligosaccharides are clinically relevant to protection against infant diarrhea.

Adolescent↗
PubMed2003

Innate protection conferred by fucosylated oligosaccharides of human milk against diarrhea in breastfed infants.

To test the hypothesis that human milk fucosyloligosaccharides are part of an innate immune system, we addressed whether their expression (1) depends on maternal genotype and (2) protects breastfed infants from pathogens. Thus the relationship between maternal Lewis blood group type and milk oligosaccharide expression and between variable oligosaccharide expression and risk of diarrhea in their infants was studied in a cohort of 93 Mexican breastfeeding mother-infant pairs. Milk of the 67 Le(a-b+) mothers contained more LNF-II (Le(a)) and 3-FL (Le(x)) (oligosaccharides whose fucose is exclusively alpha 1,3- or alpha 1,4-linked) than milk from the 24 Le(a-b-) mothers; milk from Le(a-b-) mothers contained more LNF-I (H-1) and 2'-FL (H-2), whose fucose is exclusively alpha 1,2-linked. The pattern of oligosaccharides varied among milk samples; in each milk sample, the pattern was summarized as a ratio of 2-linked to non-2-linked fucosyloligosaccharides. Milks with the highest ratios were produced primarily by Le(a-b-) mothers; those with the lowest ratios were produced exclusively by Le(a-b+) mothers (p<0.001). Thus maternal genetic polymorphisms expressed as Lewis blood group types are expressed in milk as varied fucosyloligosaccharide ratios. The four infants who developed diarrhea associated with stable toxin of Escherichia coli were consuming milk with lower ratios (4.4 +/- 0.8 [SE]) than the remaining infants (8.5 +/- 0.8; p<0.001). Furthermore, the 27 infants who developed moderate to severe diarrhea of any cause were consuming milk with lower ratios (6.1 +/- 0.9) than the 26 who remained healthy (10.5 +/- 1.9; p = 0.042). Thus, milk with higher 2-linked to non-2-linked fucosyloligosaccharide ratios affords greater protection against infant diarrhea. We conclude that specific oligosaccharides constitute a major element of an innate immune system of human milk.

Adult↗
PubMed2003

Noroviruses bind to human ABO, Lewis, and secretor histo-blood group antigens: identification of 4 distinct strain-specific patterns.

We characterized the binding of 8 Noroviruses (NORs) to histo-blood group antigens (HBGAs) in human saliva using recombinant NOR (rNOR) capsid proteins. Among the 8 rNORs tested, 6 formed viruslike particles (VLPs) when the capsid proteins were expressed in insect cells, all of which revealed variable binding activities with saliva; the remaining 2 rNORs did not form VLPs, and the proteins did not bind, or bound weakly, to saliva. Four distinct binding patterns were associated with different histo-blood types, defined by Lewis, secretor, and ABO types. Three patterns (VA387, NV, and MOH) recognized secretors, and 1 pattern (VA207) recognized Lewis-positive nonsecretors. The 3 secretor-recognizing patterns were defined as A/B (MOH), A/O (NV), and A/B/O (VA387) binders. Oligosaccharides containing the Lewis and ABH antigenic epitopes were involved in binding. Our findings suggest that different strains of NORs may recognize different human HBGAs on intestinal epithelial cells as receptors for infection.

ABO Blood-Group System↗
PubMed2002

Homologous versus heterologous immune responses to Norwalk-like viruses among crew members after acute gastroenteritis outbreaks on 2 US Navy vessels.

Host immune responses to human caliciviruses are difficult to study because of the lack of a clear definition of antigenic or serological types. This report describes antibody responses to several Norwalk-like viruses in large outbreaks of acute gastroenteritis on 2 US Navy ships. Enzyme immunoassays (EIAs) were used to measure antibody responses. To understand the antibody response to a homologous strain causing the outbreaks, the viral capsid gene of one isolate (C59) was expressed in baculovirus and included in the EIAs. Significantly greater seroresponses were detected in patients against the homologous strain than against the heterologous strains. Strains within genogroups reacted more strongly than did strains between genogroups. Significantly higher antibody titers against the outbreak strain were detected in acute serum samples from control subjects than in those from case patients. These results indicate that recombinant EIAs are useful for outbreak investigation and that the homologous antibody might be protective against reinfection.

Acute Disease↗
PubMed2002

Determinants of optimal breast-feeding in peri-urban Guatemala City, Guatemala.

OBJECTIVE: This survey was conducted to identify factors affecting early initiation of breast-feeding and exclusive breast-feeding among mothers in peri-urban Guatemala City, Guatemala. MATERIALS AND METHODS: In early November 1999 a census was begun in four communities of peri-urban Guatemala City, Guatemala, to identify all children < 6 months old as well as all pregnant women who were expected to deliver during the two-month data-gathering period. After the census was completed, a survey of breast-feeding practices was administered to all mothers of infants < 6 months of age. RESULTS: The most important determinant of early initiation of breast-feeding was place of delivery. Children born at home (odds ratio (OR) = 4.1, 95% confidence interval (CI): 1.2-13.3) and at Ministry of Health health centers (OR = 4.9, 95% CI: 1.6-15.0) were significantly more likely than children born at private hospitals to initiate breast-feeding early. The most important determinant of exclusive breast-feeding was whether or not the mother worked outside the home. After controlling for infant's age and sex and mother's ethnicity, women who did not work outside the home were 3.2 times as likely (95% CI: 1.6-6.4) to exclusively breast-feed as were women who worked outside the home. Lack of exclusive breast-feeding was often associated with giving a bottle. CONCLUSIONS: Our findings suggest that global efforts must be continued to improve breast-feeding practices in delivery hospitals. In addition, community-based support of breast-feeding is needed well after delivery. Mothers who work outside the home should be provided with options to maintain exclusive breast-feeding when they are physically separated from their infants due to the demands of work.

Adult↗
PubMed2002

The impact of mother-to-mother support on optimal breast-feeding: a controlled community intervention trial in peri-urban Guatemala City, Guatemala.

OBJECTIVE: To assess the impact that a mother-to-mother support program operated by La Leche League Guatemala had on early initiation of breast-feeding and on exclusive breast-feeding in peri-urban Guatemala City, Guatemala. MATERIALS AND METHODS: A population census was conducted to identify all mothers of infants < 6 months of age, and the mothers were then surveyed on their breast-feeding practices, in two program communities and two control communities. Data collection for this follow-up census and survey was carried out between November 2000 and January 2001, one year after a baseline census and survey had been conducted. RESULTS: At follow-up, 31% of mothers in the program communities indicated that counselors had advised them about breast-feeding, 21% said they had received a home visit, and 16% reported attending a support group. Community wide rates of early initiation of breast-feeding were significantly higher in program areas than in the control communities, at both baseline and follow-up. However, the change over time in early initiation in program communities was not significantly different from the change in control communities. Community wide rates of exclusive breast-feeding were similar in program and control sites and did not change significantly from baseline to follow-up. However, of the mothers in the program communities who both received home visits and attended support groups, 45% of them exclusively breast-fed, compared to 14% of women in program communities who did not participate in those two activities. In addition, women who were exposed to mother-to-mother support activities during the year following the baseline census and survey were more likely than mothers exposed before that period to exclusively breast-feed. This suggests that the program interventions became more effective over time. CONCLUSIONS: This study does not provide evidence of population impact of La Leche League's intervention after one year of implementation. In peri-urban Guatemala, long-term community-based interventions, in partnership with existing health care systems, may be needed to improve community wide exclusive breast-feeding rates.

Adult↗