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J Jolles

Publications and source records attributed to J Jolles.

At least 145 records · Page 8Linked to original sources
PubMed1992

Age-related changes in concentrations of vasopressin in the central nervous system and plasma of the male Wistar rat.

The results of studies on the influence of age on concentrations of vasopressin (VP) in blood plasma and hypothalamic and extrahypothalamic brain sites have not been unequivocal. Studies on extrahypothalamic concentrations of VP in the aging rat have used two age groups only and have mainly provided semiquantitative data. For these reasons we determined, by radioimmunoassay, the concentrations of vasopressin in thirteen brain structures and in the plasma of 3-, 10-, 20- and 28-month-old male Wistar rats. Age-related decreases in VP concentrations were found in the pituitary gland, hypothalamus, thalamus, midbrain, medulla oblongata, amygdala and pineal gland, while an increase was noted in plasma. Decreases in the concentration of VP in the amygdala and pineal gland occurred between 3 and 10 months of age and probably represent developmental changes. In the pituitary, thalamus, midbrain, medulla oblongata and plasma, differences in the concentration of VP were also found between 10-month-old and older animals and are probably related to aging. The finding of increased plasma VP concentrations in aged animals agrees with the notion that neuronal function does not necessarily decline with age and suggests that neurons may even be activated. Age-related changes in VP concentrations were not observed in the other structures examined. It has been reported that the VP innervation of a number of brain structures depends on testosterone. Despite reports to the contrary VP concentrations do not generally decline in these structures with aging.

Aging↗
PubMed1992

Recall and recognition memory deficits in depression.

The aim of the present study was to establish the nature of memory deficits of depressive subjects in word learning tests. A word learning test consisting of 1, 3 or 5 learning trials was used. We found that patients were characterized by inferior memory recall compared to controls when 5 learning trials were given. Patients performed significantly slower than controls on a recognition test but both patients and controls recognized the same number of words. This suggests that the memory deficits that are present in many depressive subjects may be restricted to impaired active retrieval from memory. A second experiment revealed that recognition memory and delayed recall as well as immediate recall were impaired in depressive patients after 1 learning trial. These short-comings vanished after 3 trials, except for immediate recall. These data suggest that not only retrieval but also encoding of information into memory may be impaired in depression, especially in the beginning of a task when demands on cognitive effort are high. The results are discussed in terms of resource allocation and demands on effort that may change in the course of a task.

Adult↗
PubMed1992

Brain phosphatidic acid and polyphosphoinositide formation in a broken cell preparation: regional distribution and the effect of age.

The effect of age on phosphate incorporation into phosphatidylinositol 4-phosphate (PIP), phosphatidylinositol 4,5-bisphosphate (PIP2) and phosphatidic acid (PA) was studied. Lysed crude synaptosomal fractions of different brain regions of 3-month-old and 32-month-old Brown Norway rats were used. The brain regions tested were the hippocampus, frontal cortex, occipital/parietal cortex, entorhinal/pyriformal cortex, striatum/septum, thalamus and hypothalamus. The individual specific phosphorylating activities were unevenly distributed within the brain of Brown Norway rats. Strikingly, the distribution of phosphate incorporation into PIP2 was opposite from that of phosphate incorporation into PA. Phosphate incorporation into PA decreased (-15%) with age in almost all brain regions tested, whereas phosphate incorporation into PIP2 decreased with age only in the frontal cortex (-20%) and in the hypothalamus (-8%). The effects of age may reflect a deterioration of phosphoinositide metabolism, with its function in signal transduction coupled to receptors via G-proteins, in the brain regions involved. In addition, there was an age related decrease in protein content and total phospholipid phosphorus content of lysed crude synaptosomal preparations of all brain regions. The high correlation between the changes in these parameters may be indicative of a decrease in the number or size of synaptosomes with age in the brain regions involved.

Adenosine Triphosphate↗
PubMed1992

Neurobehavioral aspects of postconcussive symptoms after mild head injury.

The sequelae of severe closed head injury have received much attention in the literature, but the effects of mild closed head injury (MHI) are less well established. There is a subgroup of patients who complain of persisting postconcussive symptoms (PCS) beyond the first weeks of recovery. Although the symptoms generally develop in the absence of clear neurological abnormalities, the condition of PCS can be chronic and disabling. It has been assumed that PCS result from an interaction between organic and psychological factors. Differentiating between the effect of primary neurological injury and secondary psychosocial problems is often difficult for clinicians and engenders controversy. Neuropsychological, neurophysiological, and neuroimaging measures can be helpful in selecting patients at risk of developing PCS. Assessment of the level of cognitive functioning, individual susceptibility to stress, and environmental demands may be beneficial in treating symptomatic patients. It is true that the vague and aspecific nature of the postconcussion syndrome may have given rise to the controversy over this entity, but the many methodological inconsistencies in the experimental approaches to the syndrome have certainly enhanced the confusion about this issue. The ensuing controversy surrounding research on the outcome of MHI and the postconcussion syndrome reflects ambiguities in definition, inconsistencies in criteria for patient selection, variation in procedures for neurobehavioral assessment, and difficulty in obtaining follow-up data.

Brain Concussion↗
PubMed1992

Phosphatidylinositol kinase is reduced in Alzheimer's disease.

Phosphatidylinositol (PI) kinase and PI phosphate (PIP) kinase activities were measured in postmortem samples of brain tissue from patients with Alzheimer's disease and nondemented control subjects. A membrane-free cytosolic fraction from four neocortical locations, with exogenous inositol lipids as the substrate, was used. Tissue from patients with Alzheimer's disease was characterized by reduced PIP formation; the reduction was 50% in prefrontal cortex, temporal cortex, and parietal cortex and 40% in precentral gyrus. In contrast, no alterations were found in PI bisphosphate formation in these four neocortical locations. The specific changes in PI kinase but not PIP kinase activity suggest that the findings may have functional relevance to the involvement of brain membrane processes in Alzheimer's disease.

1-Phosphatidylinositol 4-Kinase↗
PubMed1992

Performance in the Stroop color word test in relationship to the persistence of symptoms following mild head injury.

There is much controversy about whether the persistence of postconcussive symptoms (PCS) in mild head injured patients (MHI) is related to the presence of cognitive deficits. Most studies performed so far have relied on normal non-concussed control subjects rather than directly comparing patients with and without PCS following MHI. In addition, subtle cognitive deficits may be present in MHI patients that are demonstrable only with more demanding cognitive tasks. In the present study the Stroop Color Word Interference Test together with a more demanding modified interference subtask was administered to two groups of patients with uncomplicated MHI 10 days, 5 weeks and 3 months after the injury. Ten patients with persistent symptoms at 3 months were selected and individually matched with MHI patients who had initially reported symptoms but who had recovered by 3 months. The scores of the two retrospectively defined groups were compared at the different time points. Between-subjects analysis revealed overall differences for both the original and modified color word interference subtask. Within-subject analysis indicated that only the recovery rate in the modified interference subtask was significantly different between the two groups. The observation that there was a parallel trend between recovery and persistence of PCS and performance on the cognitive interference measures supports the notion that there is a functional relationship between these two phenomena.

Adult↗
PubMed1992

Recovery from visual and acoustic hyperaesthesia after mild head injury in relation to patterns of behavioural dysfunction.

Patients with head injuries frequently complain of a decreased ability to endure intense light and sound stimuli. The few psychophysical studies that have objectively studied this type of hyperaesthesia have not assessed to what extent patients recover from this hyperaesthesia after mild head injury (MHI). A computerised rating technique was used to assess tolerance to intense sound (95 dB) and light (1500 lux) stimuli in patients with an uncomplicated MHI. Patients were tested 10 days and five weeks after the injury. Although most patients substantially recovered from both visual and acoustic hyperaesthesia, 25% of the patients were still not able to endure intense stimuli by five weeks. Analysis of data obtained with two behavioural rating scales (one with post-concussive/cognitive complaints and a second with emotional/vegetative complaints) indicated that visual hyperaesthesia was specifically related to the post-concussive/cognitive complaints scale.

Adult↗
PubMed1992

Changes in plasma vasopressin concentration and plasma osmolality in relation to age and time of day in the male Wistar rat.

The influence of age on several parameters related to water balance was studied in Wistar rats. Plasma AVP concentration and plasma osmolality were increased at midday in 21-month-old rats as compared with 3- and 4-month-old rats. Daily water intake per 100 g body weight was reduced in 14- and 21-month-old rats as compared with 3- and 4-month-old rats, but total water intake was unaltered. These results suggest that there is a change in water balance in Wistar rats with age. In order to obtain information about the influence of age on daily fluctuations in plasma AVP concentration and osmolality these parameters were determined in 4-month-old Wistar rats sacrificed at 2 h intervals during the day and in 20- and 31-month-old rats sacrificed at 8 h intervals. Plasma AVP concentrations were low during the light period and high during the dark period in 4-month-old rats. The relationship between plasma osmolality and plasma AVP concentration was dependent on the time of day in 4-month-old-rats. Plasma AVP concentrations were higher at 16.00 than at 08.00 and 24.00 in 20-month-old rats, and higher at 24.00 than at 08.00 and 16.00 in 31-month-old rats. In contrast to the plasma AVP concentration during the light period, the average daily AVP concentration (average of plasma AVP concentrations at 08.00, 16.00 and 24.00) was increased in 31-month-old rats only. The relationship between plasma osmolality and plasma AVP concentration was not age-related.(ABSTRACT TRUNCATED AT 250 WORDS)

Aging↗
PubMed1992

Pitfalls in the measurement of plasma osmolality pertinent to research in vasopressin and water metabolism.

The reliability of measurements of plasma osmolality is known to be biased by technical artifacts, such as the anticoagulant and the osmometric technique used; the resulting measurement errors therefore may cause errors in interpretation of data. In assessing the potential biasing influence of procedural variables, we found that the temperature at which fresh plasma samples were stored, the duration of storage, and the freezing and thawing of samples appeared to significantly (P < 0.01) affect osmolality values around the narrow physiological range. These factors should be considered in the interpretation of studies on the osmoregulation of vasopressin secretion. In particular, the results suggest that data obtained for any but fresh samples, whether frozen-thawed samples or samples stored at room temperature, are unreliable.

Blood↗
PubMed1992

[The elderly and memory complaints. A study of self-knowledge about memory, depression and memory abilities].

A group of 24 elderly persons who applied for a memory training because of memory complaints is compared with a control group of 24 healthy persons (matched for age, sex, and education). The comparison concerned several memory tests, complaints above everyday memory, depression and aspects of meta-memory. Before training, the memory training group had more complaints about everyday memory and depression compared to the control group. The training group reported more decline in memory capacity and functioning compared to their earlier days. They also reported feelings of stress and anxiety related to memory performance in daily life. Before training, the training group had more general knowledge about basic memory processes and used memory strategies more frequently. On most memory tests no differences were found. Memory complaints of elderly people may therefore not only be related to memory abilities according to tests but also to individual (negative) beliefs in memory capacity and abilities.

Aged↗
PubMed1992

Neuropsychological deficits in patients with persistent symptoms six months after mild head injury.

There is much debate on the nature and duration of cognitive deficits and postconcussive symptoms (PCS) after mild head injury. Most studies performed so far have compared head-injured patients with subjects who had not suffered a concussion, instead of directly comparing patients with and without persistent PCS. The present study examined whether patients with PCS (n = 9) about 6 months after an uncomplicated mild head injury performed less well on selected neuropsychological tests than patients with mild head injuries who did not have PCS (n = 9) and healthy controls (n = 9). Patients with PCS were individually matched with controls for the time elapsed after the injury, age, sex, and education. We found that patients with PCS performed less well on tests of divided and selective attention than both patients without PCS and healthy controls. It is concluded that cognitive deficits may be present up to 6 months after mild head injury when symptoms persist. The findings indicate that patients with mild head injury and subjective symptoms may manifest demonstrable cognitive deficits.

Adult↗
PubMed1992

[Screening for dementia: validity of the Cognitive Screening Test (CST) and the Mini-Mental State Examination].

The Cognitive Screening Test (CST--short version), a Dutch orientation questionnaire, and the Mini-Mental State Examination (MMSE) were compared with respect to their ability to discriminate between mildly demented, moderately demented and non-demented patients. The difference between mildly and moderately demented patients was based on the Global Deterioration Scale score. The CST and the MMSE were administered to patients who had been referred to the Memory Clinic of the University Hospital of Maastricht. Both instruments were successful in discriminating moderately and severely demented from non-demented patients. The CST and the MMSE were also successful with respect to the classification of depressive, non-demented elderly patients. The CST did not succeed in the correct classification of mildly demented patients (50% false-negative). The results of the MMSE in this group of mildly demented patients were moderate (25% false-negative). It is concluded that the value of both screening instruments, and especially the short version of the CST is limited for clinical practice.

Aged↗
PubMed1991

Tolerance for light and sound of patients with persistent post-concussional symptoms 6 months after mild head injury.

Patients with post-concussional symptoms (PCS) about 6 months after a mild head injury (MHI) were examined for tolerance of light and sound in comparison with concussed patients without PCS and non-concussed healthy controls. MHI patients with PCS were individually matched with subjects from the two control groups for the time elapsed from the injury, and for age and sex. Using a computerized rating technique, we assessed both the maximal and submaximal levels of lowered tolerance for light and sound over a wide range of stimuli. We found that the MHI patients with PCS 6 months after the trauma (n = 11) tolerated significantly less well stimuli of intensities of 71 dB and 500 lx than MHI patients without PCS (n = 11) and non-concussed controls (n = 11). There were no significant differences in tolerance for light and sound between MHI patients without PCS and the non-injured controls. Decreased tolerance for light and sound may contribute to the persistence of symptoms up to 6 months after a mild head injury. The psychophysical method provides an objective measure for the evaluation of the late persistent post-concussional syndrome.

Acoustic Stimulation↗
PubMed1991

Coping style, trait anxiety and cortisol reactivity during mental stress.

The present study examined whether salivary cortisol secretion as an index of stress reactivity to continuous mental task performance reflected individual differences in coping styles. During 4 hr of continuous mental tasks significantly higher cortisol levels were found in comparison with a control session. However, individual variability in the cortisol response was high. Correlational data indicate a significant negative relationship between the coping style 'comforting cognitions' and the individual cortisol response during mental stress. During this particular type of cognitive stress, where the subject has no control over the experimental situation, comforting and emotion-focused coping may be effective because of the subject's efforts of trying to reframe the inevitable situation in a positive and self-encouraging way. In contrast, there was no significant relationship between trait anxiety and individual glucocorticoid susceptibility to mental stress.

Adaptation, Psychological↗
PubMed1991

Rigorous health screening reduces age effect on memory scanning task.

Eighty subjects participated in a study with five age groups (20, 30, 40, 50, and 60 years). Forty subjects showed evidence of factors related to brain dysfunction (risk factors). Their performance on a Sternberg-type memory scanning task was assessed. Age-related slowing of virtually all aspects of the memory scanning process was observed in the healthy group. However, the effect of the presence of risk factors was larger than that of biological age. The results of the present study make a reasonable case for the view that many age effects reported in the literature can be largely explained by suboptimal brain functioning, i.e., by other factors than aging per se.

Adult↗
PubMed1991

Differential diagnosis of dementia: a comparison between the expert system EVINCE and clinicians.

The diagnostic performance of the expert system EVINCE was compared with that of 85 clinicians in diagnosing 10 patients suspected of suffering from dementia. A multidisciplinary expert committee provided a standard diagnosis as reference for comparison. The results showed that the syndrome and etiologic diagnoses made by EVINCE were in very close agreement with those of the expert committee and that the diagnostic performance of EVINCE was better than that of the average clinician. The present findings indicate that expert systems, especially those within the realm of complex multidimensional medical problems, could be a valuable aid in medical practice.

Aged↗
PubMed1991

A psychophysical method for assessing visual and acoustic hyperaesthesia in patients with mild head injury.

Although it is well known that patients with mild head injury (MHI) are less able to endure intense light and sound stimuli than normal people, there are few psychophysical studies that have objectively measured this type of hyperaesthesia. In the present study, using a computerised rating scale technique, both the maximal and submaximal levels of reduced tolerance to light and sound were assessed for a wide range of stimuli. Three to six days after the trauma, 40 MHI patients were significantly less tolerant to stimuli of intensities over 71 dB and 500 lux levels than controls. These intensities are common, and MHI patients may suffer as a consequence.

Adult↗