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PubMed2005

Longitudinal evaluation of cerebral morphological changes in Parkinson's disease with and without dementia.

OBJECTIVE: To investigate the pattern of brain atrophy across time in a sample of Parkinson's disease (PD) patients with and without dementia using voxelbased morphometry (VBM) analysis. METHODS: The initial sample comprised thirteen non-demented PD patients and sixteen demented patients. Longitudinal cognitive assessment and structural MRI were performed. The mean follow-up period was 25 months (SD=5.2). From this initial group, eight PD patients with dementia (5 men and 3 women) and eleven PD patients without dementia (7 men and 4 women) were reevaluated. MRI 3D structural images were acquired and analyzed by means of the optimized VBM procedure with Statistical Parametric Mapping (SPM2). RESULTS: VBM analysis showed a progressive grey matter volume decrease in patients with PD without dementia in limbic, paralimbic and neocortical associative temporooccipital regions. In patients with dementia the loss mainly involved neocortical regions. CONCLUSION: VBM revealed a significant loss of grey matter volume in PD patients with and without dementia with disease progression. The decrease in limbic and paralimbic regions is widespread in non-demented patients. Neocortical volume reduction is the most relevant finding in patients with dementia. This suggests that the neocortex is a substrate for dementia in Parkinson disease.

Aged↗
PubMed1978

Primary affective disorder, clinical state change, and MHPG excretion: a longitudinal study.

Urinary 3-methoxy-4-hydroxyphenethylene glycol (MHPG) excretion, which is thought to reflect CNS norepinephrine metabolism, has been shown to be significantly decreased in some depressed patients. Although there is consensus that urinary MHPG excretion varies directly with mood in rapidly cycling bipolar patients, there is little information on longer term state changes, such as those that accompany recovery from depression. Ten female patients with diagnoses of primary affective disorder were studied initially during an inpatient hospitalization and restudied at least ten months after discharge. Five healthy female comparison subjects were also studied over a similar interval of time. During the baseline period, the patient sample excreted less MHPG than did the comparison group. Improvement in clinical state from a seriously depressed baseline was associated with a significant increase in MHPG excretion, while the patients with recurrences of depression showed no change and continued to excrete less MHPG than the comparison subjects. These results suggest that urinary MHPG excretion may represent an index of psychobiological state in depressive patients.

Adult↗
PubMed1996

Effects of aging on the fine structure of the 2f1-f2 acoustic distortion product.

The fine structures of 2f1-f2 acoustic distortion products (ADP) were measured in four groups of human subjects: (1) young with normal hearing, (2) aged with normal or near-normal hearing, (3) aged subjects with more severe hearing loss above 2000 Hz, and (4) young with hearing similar to those of the normal- or near-normal-hearing aged group. The purpose of this study was to investigate how ADP fine structure changes with age and hearing loss. Results show that the fine structure is observable whenever the ADP is measurable, and its sharpness, defined as the peak-to-peak frequency distance, is independent of age hearing loss, and longitudinal amplitude change. There is a large variance in ADP peak amplitudes in aged subjects with or without hearing loss as compared to young normal hearing subjects, the aged group generally having lower peak amplitudes than those of the young group. According to an ANOVA analysis with absolute threshold as covariate, the null hypothesis stating that there is no aging effect on the ADP peak responses cannot be ruled out, a conclusion similar to that made by Stover and Norton [J. Acoust. Soc. Am. 94, 2670-2681 (1993)]. On the other hand, threshold changes cannot explain all the differences in ADP amplitude. It is clear that the relationship between ADP amplitudes and behavioral thresholds can differ between young and aged populations. At primary levels of 50 dB SPL, almost normal ADP magnitudes are often found in aged subjects even when associated with a 35-dB hearing loss, whereas for young subjects ADPs typically were not measurable when associated with the pure-tone thresholds of 20 dB HL or higher. This dichotomy may be explained by the different etiologies of cochlear pathologies predominant in the two groups.

Acoustics↗
PubMed2003

Longitudinal study of sexual function and vaginal changes after radiotherapy for cervical cancer.

PURPOSE: To investigate the longitudinal course of self-reported sexual function and vaginal changes in patients disease free after radiotherapy (RT) for locally advanced, recurrent, or persistent cervical cancer. MATERIALS AND METHODS: A total of 118 patients referred for RT were included. The patients were assessed, using a validated self-assessment questionnaire, at the termination of RT and 1, 3, 6, 12, 18, and 24 months later. The results were compared with an age-matched control group from the general population. RESULTS: Persistent sexual dysfunction and adverse vaginal changes were reported throughout the 2 years after RT, with small changes over time: approximately 85% had low or no sexual interest, 35% had moderate to severe lack of lubrication, 55% had mild to severe dyspareunia, and 30% were dissatisfied with their sexual life. A reduced vaginal dimension was reported by 50% of the patients, and 45% were never, or only occasionally, able to complete sexual intercourse. Despite sexual dysfunction and vaginal adverse effects, 63% of those sexually active before having cancer remained sexually active after treatment, although with a considerably decreased frequency. CONCLUSIONS: Patients who are disease free after RT for locally advanced, recurrent, or persistent cervical cancer are at high risk of experiencing persistent sexual and vaginal problems compromising their sexual activity and satisfaction.

Adult↗
PubMedDate not supplied

[Effect of oxidizing and reducing agents on the rate of water proton relaxation in the chloroplasts of beans and particles of photosystem 2].

The change of longitudinal proton relaxation rate, 1/T1, in the native and shocked chloroplasts, PS2 chloroplasts' particles and exogenous complexes Mn2+--PPCI (pigment--protein complex of PSI), Mn2+--PPCII in the presence of the PS2 donors and acceptors and at different pH change were studied. It has been shown that 1/T1 increases in chloroplasts and PS2 particles in the presence of the PS2 donors and decreases in the presence of the acceptors in contrast to untreated preparations. The 1/T1 change of exogenous complexes is not specific. The results suggest that the manganese pool of the chloroplasts PS2 may be the main factor responsible for the chloroplasts' proton relaxation rate. The change of the manganese valency in the presence of donors and of acceptors may result in changing 1/T1.

2,6-Dichloroindophenol↗
PubMed2006

Genetic drift of parvovirus B19 is found in AIDS patients with persistent B19 infection.

It is generally thought that parvovirus B19 is stable genetically. Consistently, genetic drift has not been found in patients with persistent B19 infection. In this report, longitudinal genetic changes in NS1 and VP1 gene of B19 isolates from three AIDS patients with persistent B19 infection were studied. One of the three patients was not treated with highly active anti-retroviral therapy (HAART). B19 viral DNA from these patients was amplified by polymerase chain reaction (PCR) and then sequenced directly. A single genetic change was found in the B19 isolate obtained from the patient not treated with HAART on Day 10 after intravenous immunoglobulin (IVIG) treatment. The nucleotide sequences of B19 isolated from this patient, then remained unchanged over a period of 11 months. Analysis of NS1 clones derived from his longitudinal viral isolates showed the existence of quasi-species but genetic drift was not found. One of the other two patients treated with HAART experienced treatment failure; he was later treated with mega-HAART. In contrast to the genetic stability of B19 isolates from the patient not treated with HAART, multiple genetic changes were discovered in the viral isolates from the two other patients after HAART and mega-HAART, respectively. Through analysis of B19 clones, the frequency of clones containing these mutations confirmed the genetic drift. Nucleotide substitutions seen in VP2 gene of isolates with genetic drift from both patients were all non-conserved, suggesting that they are positively selected.

AIDS-Related Opportunistic Infections↗
PubMed2006

Behaviour changes in a transgenic model of Huntington's disease.

Huntington's disease is an autosomal dominant inherited disorder, caused by an expanded polyglutamine region of a protein called huntingtin with unknown function. Transgenic mice expressing the N-terminal of huntingtin, containing 82 glutamines, exhibit a progressive disorder, which resembles to the human disease. In this study, we tested the longitudinal behaviour changes in this transgenic line in open-field and elevated-plus-maze tests. The motor performance deteriorated at 12 weeks of age and the disease progressed as indicated by the decreased total distance covered, the decreased mean velocity and the decreased exploratory behaviour. The level of anxiety was unchanged in transgenic mice as compared with their littermate controls. The motor deterioration was similar to that in other Huntington's disease models, while the level of anxiety was different. These tests are suitable means of following the progression of the disease and useful for studies of the effects of therapeutic interventions.

Animals↗
PubMed2006

A three-year follow-up of lumbar spine endplate (Modic) changes.

STUDY DESIGN: A longitudinal follow-up of Modic changes on magnetic resonance imaging (MRI). OBJECTIVES: To assess the prevalence and natural course Modic changes over a 3-year follow-up period. SUMMARY OF BACKGROUND DATA: Modic changes are bone marrow and endplate lesions visible on MRI. To the authors' knowledge, no follow-up studies on their natural course have been published. METHODS: The study population consisted of 60 unoperated sciatica patients 23 to 76 years of age. Baseline and 3-year lumbar MR images from L1-L2 through L5-S1 were analyzed independently by 2 radiologists and a consensus reading was performed. RESULTS: At baseline, the prevalence of Modic changes was 23%. Seven discs had mixed Type I/II, and 63 Type II change. Changes typically occurred at L4-L5 and L5-S1, and associated positively with age (P = 0.009). Ten of 70 discs (14%) with Modic changes at baseline displayed another type at 3 years. Furthermore, the nonconverted changes increased significantly in size. The incidence of new Modic changes during the follow-up was 6% (13 of 230). CONCLUSIONS: Modic changes are common MRI findings in patients with degenerative lumbar disc disease. We found evidence that Modic Type II changes may be less stable than previously assumed.

Adult↗
PubMed2002

Simultaneous imaging of Ca2+ signals in interstitial cells of Cajal and longitudinal smooth muscle cells during rhythmic activity in mouse ileum.

Electrical rhythmicity in smooth muscle cells is essential for the movement of the gastrointestinal tract. Interstitial cells of Cajal (ICC) lie adjacent to smooth muscle layers and are implicated as the pacemaker cells. However, the pace making mechanism remains unclear. To study the intercellular interaction during electrical rhythm generation, we visualized changes in intracellular Ca2+ concentration ([Ca2+]i) in smooth muscle cells and myenteric ICC within segments of mouse ileum loaded with a fluorescent Ca2+ indicator, fluo-3. We observed rhythmic [Ca2+]i changes in longitudinal smooth muscle cells travelling rapidly through the smooth muscle cell layer. Between the rhythmic Ca2+ transients, we found brief Ca2+ transients localized to small areas within smooth muscle cells. The amplitude but not the periodicity of rhythmic [Ca2+]i transients in both cell types was partially inhibited by nicardipine, an L-type Ca2+ channel antagonist, suggesting that the rhythmic [Ca2+]i transients reflect membrane potential depolarizations corresponding to both slow waves and triggered Ca2+ spikes. Longitudinal smooth muscle cells and myenteric ICC showed synchronous spontaneous [Ca2+]i transients in eight out of 21 ileac preparations analysed. In the remaining preparations, the synchrony between ICC and smooth muscle cells was absent, although the rhythmicity of the smooth muscle cells was not disturbed. These results suggest that myenteric ICC may play multiple roles including pace making for physiological bowel movement.

Animals↗
PubMed1993

A longitudinal study of corneal astigmatism changes in Asian eyes.

This study investigated changes in corneal astigmatism with age of 494 Asian eyes in a retrospective study. The results are compared to previous studies of non-Asian eyes. The current study demonstrates a greater magnitude in the rate of change of corneal astigmatism.

Adolescent↗
PubMed1993

Analyzing change in short-term longitudinal research using cohort-sequential designs.

This article illustrates a method for approximating longitudinal data analysis by combining information from different overlapping age groups to form a single developmental growth curve. Using this method, hypotheses about the form of growth, the extent of individual differences in growth, and factors that affect the rate and pattern of growth are investigated. The example used to illustrate this method examines the growth of externalizing behavior and of negativity in parent-child relationships during early adolescence using assessments from multiple methods and multiple informants. These 3 dimensions changed significantly during this period, with parental negativity increasing more rapidly after age 12. However, there were substantial individual differences in the pattern of change in these dimensions. Gender of child and type of family situation (nondivorced, divorced, and remarried) were investigated as possible factors affecting change.

Adolescent↗
PubMed1985

Changes in the mechanical properties of the longitudinal and circular muscle tissues of the rat myometrium during gestation.

Changes in the mechanical properties of the longitudinal and circular muscle tissues of the rat myometrium during gestation were investigated. In isolated longitudinal and circular muscles of the rat myometrium, spontaneous contractions and contractions per unit cross-sectional area induced by 128 mM K+ and 1 X 10(-5) M acetylcholine (ACh) increased with the progress of gestation. These increases appeared in longitudinal muscles to a greater extent than in circular muscles. ACh induced the largest contraction for both intact muscle tissues, at all stages of gestation. In both muscle layers, the ACh-induced contraction reached the same amplitude as the 1 X 10(-5) M Ca-induced contraction of skinned muscles, except for the longitudinal muscle at the 22nd day of gestation. In Ca-free solution containing 2 mM EGTA, ACh produced contraction in both intact muscle tissues at all stages and the amplitude was increased during the progress of gestation, whereas the K-induced and spontaneous contractions ceased. In saponin-treated skinned muscles of both layers, the free Ca concentration required to produce contraction was lowered, the maximum amplitudes of the contraction were increased and the pCa-tension relationships shifted to the left during the progress of gestation. The results indicate that during the progress of gestation, Ca sensitivity of of the contractile proteins and mechanical responses to agonists increased and that the properties of the intracellular Ca store site were also altered in both muscle layers.

Acetylcholine↗
PubMed1996

Patterns and prediction of orthodontic treatment course.

Most attempts at the identification and prediction of treatment-related changes and outcome in orthodontics thus far have relied upon single biometric parameters instead of employing a systemic and ecological approach. The concept of facial harmony and the availability of sophisticated multivariate statistics offer new chances for a deeper understanding of the mechanisms of change. A longitudinal study has been conducted on approximately 500 youths aged 9-11 years, on average. Numerous parameters of cephalometric analysis, study casts, growth, treatment regimen and patient co-operation were assessed at the onset of treatment (T0) and after 1 year (T1) to determine treatment-related changes under therapy with removable appliances. Exploratory cluster analyses were based on five fundamental cephalometric parameters (SNA, SNB, ML-NSL, NL-NSL, NS-Ba) that establish an operational approach to harmonious facial relations (Segner and Hasund, 1991). As a first step, analyses were restricted to 281 Class II division 1 patients selected for good co-operation by an expert rating by the first author on a three-point rating scale. They all were treated with bionators either with anterior or posterior traction. Both subgroups were studied separately. Based on cluster analytic procedures, different patterns of change were identified for both types of appliance. A slight tendency toward harmonization of the initial skeletal relations was observed throughout all subgroups, with reactions being most obvious in the maxilla. The clusters produced for either appliance group were then screened for additional predictors of group membership by means of discriminant analysis. The findings are discussed in terms of the suitability of the methodological approach chosen.

Activator Appliances↗
PubMed1999

Interpreting age, period and cohort effects in plasma lipids and serum insulin using repeated measures regression analysis: the CARDIA Study.

Observed changes in health-related behaviours and disease risk factors may arise from physiological or environmental changes, or from biases due to sampling or measurement errors. We illustrate problems in the interpretation of such changes with longitudinal data from the Coronary Artery Risk Development in Young Adults (CARDIA) study. Mean plasma cholesterol was 14 mg/dl higher in 27- than in 20-year-old black men cross-sectionally, but longitudinally it declined by 4 mg/dl during the 7 years. To sort out these contradictory assessments of the effect of age/passage of time, we estimated age and period effects under the assumptions that age effects are a smooth function of age independent of period, and that period effects are changes common to persons across all ages. Simple estimates the age effect, such as the cross-sectional age slopes, may be confounded by cohort effects, by interactions of time and age after baseline, or by the occurrence of non-linearities in response after baseline. We note examples of each potential type of bias. The data and background literature support the assumption that cohort effects do not seriously compromise interpretation for these variables in the CARDIA study. Strong secular decreases in plasma cholesterol, apparently due to population-wide dietary change, mask increases with ageing. Age increases in triglycerides are largely explained by increases in body fatness. For these data, we cautiously accept the cross-sectional age slope as an estimate of ageing and the age-matched time trend as an estimate of secular trend.

Adolescent↗
PubMed1997

Identifying individuals with high fat levels and low P:S ratios, in their diets, for intensive dietary intervention.

OBJECTIVES: To assess whether simple scores from a dietary questionnaire could identify those with high dietary fat or low P:S ratio intakes, for intensive dietary intervention. DESIGN: Cross-sectional and longitudinal studies. SETTING: Community setting in the Hunter Region of New South Wales, Australia. SUBJECTS: Two random samples of adults 35-69 years from the electoral roll. In the cross-sectional study 287/322 (86%) subjects completed the diet questionnaire and a reference standard questionnaire. In the longitudinal study 546/653 (84%) of subjects completed the diet questionnaire, and had blood cholesterol measured on two occasions, 3 months apart. MAIN OUTCOME MEASURES: In the cross-sectional study, the simple scores of total fat intake (Fat Intake Score) and P:S ratio (Unsaturated Score) were compared with the daily intakes of total fat and P:S ratio obtained from the standard questionnaire. In the longitudinal study, changes in the scores were compared with changes in blood total cholesterol. RESULTS: A Fat Intake Score of greater than 125 had the best receiver operator characteristics for identifying high total fat intake (> 100 g/day: sensitivity = 67%, specificity = 70%). An Unsaturated Score of less than 0.3 had the best characteristics for identifying a low P:S ratio (< 0.5: sensitivity = 63%, specificity = 60%). Subjects who decreased Fat Intake Score by one category, had a fall in blood cholesterol of 0.14 mmol L-1 (95% confidence interval (CI) = 0.01-0.26 mmol L-1), while those decreasing by two categories decreased their blood cholesterol by 0.56 mmol L-1 (95% CI = 0.30-0.86 mmol L-1). Subjects increasing their Unsaturated Score category had a fall in blood cholesterol of 0.17 mmol L-1 (95% CI = 0.02-0.32 mmol L-1). CONCLUSION: Simple dietary scores can identify those with high fat intakes, and monitor changes related to changes in blood cholesterol levels.

Adult↗
PubMed1989

An analysis of genotype effects and their interactions by using the apolipoprotein E polymorphism and longitudinal data.

We investigate the interaction between the apolipoprotein E polymorphism and changes in weight and height as they affect the longitudinal profile of total cholesterol, triglyceride, beta lipoprotein, and glucose levels. Data were available on a sample of 466 individuals in 158 nuclear families from Nancy, France. Longitudinal data analyses were carried out on 128 unrelated adults and 56 unrelated children. We estimate the relative frequencies of the epsilon 2, epsilon 3, and epsilon 4 apolipoprotein E alleles in this population to be .120, .764, and .116, respectively. There is no significant evidence from these data that supports an effect of the apolipoprotein E polymorphism on the longitudinal profile of any of the variables considered. There is a significant interaction between the effects of this gene and weight change on the longitudinal change of serum triglyceride and beta lipoprotein levels in adults. In conjunction with weight gain, individuals with an epsilon 4 allele are expected to show a larger increase in triglyceride levels (0.15 +/- 0.03 mmol/L/kg) compared with individuals with no epsilon 4 allele. An increased production of very-low-density lipoprotein (VLDL) as one gains weight, along with retarded VLDL clearance attributable to the effects of the epsilon 4 allele, may account for this results. The significant interaction between the apolipoprotein E polymorphism and changes in weight on the longitudinal change in triglyceride levels corroborates epidemiological studies reporting that the epsilon 4 allele increases the risk of hypertriglyceridemia among obese individuals.

Apolipoproteins E↗
PubMedDate not supplied

Raised epidermal phospholipase A2 activity in rheumatoid arthritis.

Epidermal phospholipase A2 (PLA2) in RA patients was significantly higher than in normals (p less than 0.0001) but lower than in psoriatic patients (p less than 0.05). No relationship was observed between PLA2 activity and commonly used measures of rheumatoid disease activity in a cross-sectional study. However, in a longitudinal study change in PLA2 activity correlated strongly with changes in disease activity.

Adult↗