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Longitudinal changes in the mineral content of human milk.

Thirty-eight lactating women, from 1 to 31 months postpartum, provided monthly milk samples for determination of calcium, magnesium, manganese, copper, iron, and zinc. Subjects remained in the study an average of 4 consecutive months, with a maximum participation of 9 months. Subject variation accounted for the majority of variance in the raw data. After statistically controlling subject effect, copper, iron, and zinc levels were shown to be significantly related to duration of lactation. Prediction equations for these three minerals were developed, making it possible to calculate, on an individual basis, the copper, iron, and zinc levels of milk to be produced in future months. Data were also collected to determine possible correlations between breast milk mineral levels and the maternal dietary intake, serum levels, or hair concentration of these same minerals. No significant correlation was found between the milk mineral content and any of the three parameters under study.

Adult↗

The effects of a dietary zinc supplement during lactation on longitudinal changes in maternal zinc status and milk zinc concentrations.

Dietary zinc intakes, selected biochemical indices of zinc status, and milk zinc concentrations were determined at monthly intervals throughout lactation for 53 middle-income lactating women, 14 of whom received a daily supplement of 15 mg zinc. Overall mean dietary zinc intake for the non-supplemented group (NZS) was 10.7 +/- 4.1 mg/day (mean +/- SD). The mean dietary zinc intake of the zinc supplemented group (ZS) was 12.2 +/- 3.5 mg/day, with an additional 12.8 +/- 1.5 mg/day from the supplement. For the NZS group, the highest mean plasma zinc concentration of 79 +/- 10 mu/dl, which occurred at month 4, was significantly less than the mean for non-lactating control women (86 +/- 10 micrograms/dl). ZS plasma zinc levels had a pattern similar to that of the NZS group for months 1-7. The rate of decline in milk zinc during lactation was significantly less for the ZS group compared to that of the NZS group (p = 0.02). It is concluded that milk zinc concentrations are influenced by maternal zinc intake within a physiological range and that the effects of low maternal intakes are most apparent with prolonged lactation.

Adult↗

Longitudinal changes in the well-being of Japanese caregivers: variations across kin relationships.

This study examined how the psychological well-being of Japanese caregivers changed over time; it also examined the variation across kin relationships with care recipients. Three interviews over the course of 30 months were conducted with a representative sample of community-dwelling caregivers of frail elderly persons living in a Tokyo suburb. Latent growth modeling demonstrated that mean levels of both depression and emotional exhaustion worsened over time. Change in emotional exhaustion over time showed significant individual variability, whereas change in depression showed little individual variability. Although wife caregivers tended to experience the worst trajectory of emotional exhaustion, daughters-in-law also showed a similar negative trend. The difference in individuals' well-being trajectories by kinship may be explained partly by differences in care recipients' disabilities.

Affect↗

Condition-related knowledge among children with spina bifida: longitudinal changes and predictors.

OBJECTIVE: To examine changes in three domains of condition-related knowledge among youth with spina bifida and to examine the utility of youth cognitive ability level and condition severity as predictors of knowledge change. METHODS: Seventy preadolescents with spina bifida completed a 12-item questionnaire assessing knowledge of spina bifida at three time points during middle childhood and early adolescence. Specific domains of knowledge assessed included (a) etiology of spina bifida, (b) functional status, and (c) shunt functioning (completed by participants with shunted hydrocephalus only). RESULTS: Findings revealed gains in accuracy of knowledge on 6 of 12 items; however, neither children's cognitive ability level nor condition severity predicted changes in knowledge over time. Most condition domains were characterized by low-to-moderate levels of knowledge across time. CONCLUSIONS: Although significant gains were evident in children's condition-related knowledge, at Time 3, many participants still failed to understand basic information about the etiology of their condition or major functional issues associated with spina bifida. Additional education about catheterization and shunt malfunction are two domains that may be of particular clinical significance.

Adolescent↗

Longitudinal changes in word recognition by patients who use the Ineraid cochlear implant.

The time course for reacquisition of spondee word recognition was examined for 27 patients who use the Ineraid cochlear implant. At 1 month postfitting, test scores ranged from 0 to 84% correct. The median score was 10% correct. At 22 to 28 months postfitting, the scores ranged from 0 to 100% correct. The median score was 56% correct. The rate of improvement in spondee recognition varied greatly within the sample. Most patients continued to extract new information from the electrically evoked representation of the speech signal over a period of a year or more.

Cochlear Implants↗

Morphological progression of emphysema on thin-section CT: Analysis of longitudinal change in the number and size of low-attenuation clusters.

OBJECTIVES: To evaluate morphological changes in the number and size of low-attenuation clusters on computed tomography (CT) in patients with emphysema. MATERIALS AND METHODS: In 27 patients who had follow-up CT scans for 6 months or greater, initial 27 scans and follow-up 39 scans were analyzed. The number per slice (LAN/s) and mean size (LAS) of low-attenuation clusters less than -950 HU, and total low-attenuation area below -950 HU per slice (LAA-950/s) were calculated. RESULTS: LAS and LAA-950/s were significantly increased over time. No significant correlation was found between LAN/s and follow-up period. LAS increased in 37 of 39 (95%) follow-up scans, whereas LAN/s decreased in 17 of 39 (44%) follow-up scans. CONCLUSIONS: On the morphological progression of emphysema, the mean size of low-attenuation clusters was significantly increased during the follow-up period, whereas no significant correlation was found between the number of low-attenuation clusters and follow-up period.

Aged↗

Longitudinal changes in corneal asphericity in myopia.

PURPOSE: To report the change in shape of the peripheral cornea (asphericity, Q) as it relates to myopia progression in adolescence. METHODS: Forty-eight subjects with initial ages between 11 and 13 years of age were observed for 5 years. Each subject had participated in a variety of soft contact lens studies and all had worn daily wear soft contact lenses successfully for the 2 years before collection of the second data set. RESULTS: Myopia increased by an average of 1.46 D and was strongly correlated with a 0.56-mm increase in axial length. There was no contribution to the change in myopia from the change in central radius of the cornea. A significant (p < 0.01, one tail) correlation was found between Q and the progression of myopia. Principal axis analysis yielded a slope of -0.04 in Q per diopter of increase in myopia. CONCLUSION: These data show a shift to a more positive Q (in the oblate direction) with increased myopia.

Adolescent↗

Absence of longitudinal changes in rheumatologic parameters after silicone breast implantation: a prospective 13-year study.

There have been numerous questions regarding the association of polysiloxane with connective tissue disease and alteration of host immune response. C-reactive protein, rheumatoid factor, and anti-streptolysin-O titers were measured in 218 patients. These studies are routinely used in the diagnosis of autoimmune disease and mixed connective tissue disease. This prospective study has been in progress since 1985. The first patients were seen in July of 1985, and those individuals willing to participate were followed from 1985 to 1998. The implants included saline-filled elastomer shells and polysiloxane gel-filled elastomer shells. These groups were examined separately and in combination for changes between preoperative and postoperative states. In each instance, there was no statistical increase or decrease. Each patient underwent a physical examination and completed a questionnaire focusing on signs and symptoms of autoimmune and connective tissue diseases. The laboratory data and subjective clinical results demonstrated no significant differences between a nonimplanted group versus the saline group alone, the gel group alone, or the combined groups. The data failed to suggest any causal relationship between implants and autoimmune or connective tissue diseases over the study period of 13 years (since 1985).

Adult↗

Longitudinal changes in post-void residual and voided volume among community dwelling men.

PURPOSE: We describe the natural history of post-void residual (PVR) and voided volume (VV) in men. MATERIALS AND METHODS: A random sample of community dwelling men (529 men 40 to 79 years old) were followed with a sonographic PVR and VV every 2 years for up to 12 years (median 5 examinations). Men were censored at the time of treatment for a prostate condition. RESULTS: The median annual change (slope) for PVR was 2.2% (p=0.03) and for VV was -2.1% (p <0.0001). There was considerable variability in PVR slopes (25th percentile -11%, 75th percentile 18%). A rapid increase in PVR slope (greater than 80th percentile) was more likely in men with a baseline American Urological Association Symptom Index greater than 7 (age adjusted odds ratio [OR]1.6, 95% CI 1.0 to 2.5). There was less variability in VV slopes (25th percentile -8.0%, 75th percentile 3.1%). A rapid decrease in VV slope (less than 20th percentile) was more likely in men with baseline age 70 to 79 years than 40 to 49 years (OR 3.9, 95% CI 2.1 to 7.2) and in men with a baseline PVR greater than 50 ml (age adjusted OR 2.1, 95% CI 1.2 to 3.6). CONCLUSIONS: Although it is highly variable, there is progressive bladder dysfunction in community dwelling men as they age. In addition, signs and symptoms attributed to benign prostatic hyperplasia were modest predictors of the development of bladder dysfunction. A baseline increased PVR predicted a rapid decrease in VV, consistent with a bladder outlet obstruction contributing to the development of detrusor overactivity and decreased bladder compliance.

Adult↗

Longitudinal changes in the bacterial community composition of the Danube River: a whole-river approach.

The Danube River is the second longest river in Europe, and its bacterial community composition has never been studied before over its entire length. In this study, bacterial community composition was determined by denaturing gradient gel electrophoresis (DGGE) analysis of PCR-amplified portions of the bacterial 16S rRNA gene from a total of 98 stations on the Danube River (73 stations) and its major tributaries (25 stations), covering a distance of 2,581 km. Shifts in the bacterial community composition were related to changes in environmental conditions found by comparison with physicochemical parameters (e.g., temperature and concentration of nutrients) and the concentration of chlorophyll a (Chl a). In total, 43 distinct DGGE bands were detected. Sequencing of selected bands revealed that the phylotypes were associated with typical freshwater bacteria. Apparent bacterial richness in the Danube varied between 18 and 32 bands and correlated positively with the concentration of P-PO(4) (r = 0.56) and negatively with Chl a (r = -0.52). An artificial neural network-based model explained 90% of the variation of apparent bacterial richness using the concentrations of N-NO(2) and P-PO(4) and the distance to the Black Sea as input parameters. Between the cities of Budapest and Belgrade, apparent bacterial richness was significantly lower than that of other regions of the river, and Chl a showed a pronounced peak. Generally, the bacterial community composition developed gradually; however, an abrupt and clear shift was detected in the section of the phytoplankton bloom. Large impoundments did not have a discernible effect on the bacterial community of the water column. In conclusion, the riverine bacterial community was largely influenced by intrinsic factors.

Bacteria↗

Symptoms and longitudinal changes in lung function in young seasonal grain handlers.

A total of 119 seasonal grain handlers (mean age 23) were assessed before and towards the end (mean work period 18 days) of the 1983 Western Australian grain harvest to determine if respiratory symptoms that occur with exposure to grain dust are associated with changes in ventilatory capacity or non-specific bronchial reactivity to methacholine. Eighteen per cent of subjects had wheeze, breathlessness, or chest tightness and 18% had cough or sputum production at work. Subjects complaining of wheeze, chest tightness, or breathlessness at work had a significantly greater decline in FEV1 than subjects who did not experience these symptoms (p less than 0.05). Symptoms were not associated with changes in bronchial reactivity. In young grain handlers who develop respiratory symptoms on short term exposure to grain dust changes in FEV1 but not in non-specific bronchial reactivity have been demonstrated.

Adolescent↗

Longitudinal changes of metabolites in frontal lobes after hemorrhagic stroke of basal ganglia: a proton magnetic resonance spectroscopy study.

BACKGROUND AND PURPOSE: We investigated serial metabolic changes in frontal lobes of patients with deep intracerebral hemorrhage (ICH) to examine the correlation between N-acetylaspartate (NAA) and degree of motor impairment or clinical outcome. METHODS: - Twenty patients with deep ICH were examined with proton magnetic resonance spectroscopy with the application of a multivoxel method (1 voxel=10x10x20 mm; 64 voxels). NAA/creatine ratios in the white matter of the primary motor and premotor areas on both sides were measured sequentially: within 48 hours, at 2 weeks, and 1 month after onset. The National Institutes of Health Stroke Scale and Barthel Index for disability were measured for each patient. RESULTS: - In the primary motor area on the affected side, where the hematoma did not extend, the NAA/creatine ratio decreased sequentially. At 48 hours and 2 weeks after onset, a negative correlation was detected between NAA/creatine and hematoma volume, but there was no correlation 1 month later. At 2 weeks, NAA/creatine correlated negatively with motor impairment (r=-0.750), and there was a significant correlation with clinical outcome as early as 2 weeks after onset (r=0.954). These sequential changes of NAA/creatine varied according to patients' long-term clinical outcome. Patients with poor outcome demonstrated notable reduction of NAA/creatine over the bilateral frontal lobes. CONCLUSIONS: - The delayed gradual reduction of NAA/creatine ratio in the frontal lobes correlates with motor deficit and clinical outcome after deep ICH, suggesting that the neural networks in the frontal lobe could be important for recovery.

Aged↗

Longitudinal changes in physiological, radiological, and health status measurements in alpha(1)-antitrypsin deficiency and factors associated with decline.

The FEV(1) declines rapidly in alpha(1)-antitrypsin deficiency (alpha(1)-ATD) but less is known about other measures of disease severity and the factors, other than smoking, that are associated with progression of emphysema. The natural history of alpha(1)-ATD was studied prospectively in 43 patients with the PiZ phenotype and emphysema at a single center over 2 yr. The mean +/- SE change in FEV(1) was -67 +/- 14 ml/yr, accompanied by a reduction in transfer factor (mean change in diffusing capacity of the lung for CO [DL(CO)] -1.07 +/- 0.21 ml/min/mm Hg/yr; p < 0.001) and lung density in the upper zones as assessed by quantitative high-resolution computed tomography (HRCT) (mean change in voxel index 2.8 +/- 0.6%/yr; p < 0.001). The decline in FEV(1) related to baseline FEV(1) (r = -0.56, p < 0.001), bronchodilator reversibility (r = 0.52, p < 0.001), and (for patients with FEV(1) > 35% predicted) exacerbation frequency (r = -0.38, p = 0.02). There was also a decline in the St. George's Respiratory Questionnaire (SGRQ) Activity score (mean change -4.3 +/- 1.2 units/yr, p < 0.001) that correlated with FEV(1) decline (r = 0.45, p = 0.002). Progression of emphysema in alpha(1)-ATD is dependent on baseline physiology and exacerbation frequency and may be detected by several different measurements of which HRCT density mask analysis and DL(CO) appear most sensitive.

Adult↗

Tyramine infusions in bipolar illness: behavioral effects and longitudinal changes in pressor sensitivity.

Steady state intravenous tyramine dose pressor-response tests were administered to a patient with bipolar illness during depressed and hypomanic phases of her illness. The greatest tyramine sensitivity while unmedicated occurred when the patient was hypomanic, and the least sensitivity when she was depressed before her first switch. The data raise the possibility that changes in peripheral alpha-adrenergic receptor sensitivity accompany spontaneous mood cycles. Tyramine produced a replicable mood and cognitive alteration only in the infusion closest to the switch from hypomania to depression, suggesting that the CNS may be particularly susceptible to peripheral noradrenergic inputs at specific points in bipolar illness.

Adult↗

Organization of partner knowledge: relationship outcomes and longitudinal change.

This study examined the association between organization of knowledge about a romantic partner (partner structure) and relationship status (ongoing or ended) 1 year later. Ironically, partner structures that were associated with more positive feelings about one's partner at Time 1 were associated with greater rates of breakup by Time 2. These results are interpreted in terms of the vulnerability of compartmentalized partner structures to shifts in the salience of negative beliefs and the hypothesized difficulty of maintaining integrative structures for an extended period of time. Change in partner structure during 1 year's time was consistent with the predictions of the dynamic model that evaluative integration should increase when negative beliefs become salient. Such change (which may represent a transient shift) was associated with couples' longevity when relationship conflict was low, supporting the view that integration reflects a struggle with negative attributes that may or may not be successful.

Adolescent↗