Dietary intake of B(6-9-12) vitamins, serum homocysteine levels and their association with depressive symptoms: the Zutphen Elderly Study

OBJECTIVE: Low B-vitamin status and high levels of serum homocysteine are found in depressed inpatients, but results of population-based studies of this association are inconclusive. We investigated whether a low dietary intake of B(6-9-12) vitamins and high levels of serum homocysteine are associated with depressive symptoms in elderly men. METHODS: The study sample included a total of 332 men aged 70-90 years who were free from cardiovascular diseases and diabetes at baseline in 1990. Depressive symptoms were measured with the Zung Self-rating Depression Scale at baseline in 1990 and dietary factors with the crosscheck dietary history method in 1985 and 1990. Serum levels of homocysteine were obtained in 1985. Multiple linear and logistic regression analyses were performed. RESULTS: Dietary intake of folate (-1.19, 95% CI -2.03; -0.36) and vitamin B(6) (-2.09, 95% CI -2.92; -1.26) per standard deviation increase was associated with lower levels of serum homocysteine, while vitamin B(12) was not associated with serum homocysteine. Intake of folate, vitamin B(6), vitamin B(12) and levels of serum homocysteine were not related to depressive symptoms. CONCLUSIONS: Our results do not support the hypothesis that a low dietary intake of B(6-9-12) vitamins and high levels of serum homocysteine are related to depression in healthy elderly men.     

Kindling increases the K(+)-evoked Ca2(+)-dependent release of endogenous GABA in area CA1 of rat hippocampus

The release of endogenous amino acids from hippocampal CA1 subslices under basal conditions and the release evoked by high potassium (50 mM K+) depolarization was studied during kindling epileptogenesis. Emphasis was put on the release of the amino acid neurotransmitters gamma-aminobutyric acid (GABA) and glutamate. Kindling was induced by tetanic stimulation of the Schaffer-collaterals/commissural fibers of the dorsal hippocampus of the rat. The calcium-dependent GABA release in the presence of high K+ was significantly increased (40-46%) in fully kindled animals, 24 h after the last seizure, in comparison to controls. At long-term, 28 days after the last seizure, the calcium-dependent GABA release was still significantly increased (45-49%). An increased release of GABA in kindled animals was still found when GABA uptake was blocked by nipecotic acid. In contrast, no significant alterations were encountered in the basal or high potassium induced release of the excitatory amino acids aspartate and glutamate. These results suggest that kindling epileptogenesis is accompanied by a specific and long-lasting enhancement of GABA exocytosis which may lead to a desensitization of the GABA receptor, and thus determine the increase of seizure sensitivity.     

Self-Verification Strivings in Children Holding Negative Self-Views: The Mitigating Effects of a Preceding Success Experience

Research among adults has consistently shown that people holding negative self-views prefer negative over positive feedback. The present study tested the hypothesis that this preference is less robust among pre-adolescents, such that it will be mitigated by a preceding positive event. Pre-adolescents (n = 75) holding positive or negative global self-esteem were randomized to a favorable or unfavorable peer evaluation outcome. Next, preferences for positive versus negative feedback were assessed using an unobtrusive behavioral viewing time measure. As expected, results showed that after being faced with the success outcome children holding negative self-views were as likely as their peers holding positive self-views to display a significant preference for positive feedback. In contrast, children holding negative self-views displayed a stronger preference for negative feedback after being faced with the unfavorable outcome that matched their pre-existing self-views.     

Effect of conjugated linoleic acid supplementation after weight loss on appetite and food intake in overweight subjects

OBJECTIVE: To study the effects of 13 weeks conjugated linoleic acid (CLA) supplementation in overweight subjects on body-weight maintenance, parameters of appetite and energy intake (EI) at breakfast after weight loss. DESIGN: This study had a double-blind, placebo-controlled randomized design. SUBJECTS: A total of 26 men and 28 women (age 37.8+/-7.7 y; body mass index 27.8+/-1.5 kg/m(2)). INTERVENTIONS: Subjects were first submitted to a very-low-calorie diet (VLCD; 2.1 MJ/day) for 3 weeks after which they started with the 13-week intervention period. They either received 1.8 g CLA or placebo per day or 3.6 g CLA or placebo per day. Additionally, subjects of the high dosage intervention replaced their habitual lunch by one meal of a protein-rich, low-energy supplement. EI was measured at breakfast and appetite profile after an overnight fast. RESULTS: The mean body weight loss was 6.9+/-1.7% of their original body weight. Multiple regression analysis showed that at the end of the 13-week intervention, CLA did not have an effect on body weight regain. Feelings of fullness and satiety were increased and feelings of hunger were decreased after 13 weeks intervention by CLA compared to placebo, independent of %body weight regain. However, EI measured at breakfast was not affected by CLA. CONCLUSION: Appetite (hunger, satiety and fullness) was favorably, dose-independently affected by a 13-week consumption of 1.8 or 3.6 g CLA/day. This did not result in a lower EI at breakfast or an improved body-weight maintenance after weight loss.     

Current source density of sustained potential shifts associated with electrographic seizures and with spreading depression in rat hippocampus

The membrane currents responsible for the sustained potential shifts associated with electrographic seizures and with spreading depression in hippocampus were studied in the anesthetized rat. Probes incorporating 16 sensors in a straight line, spaced at 150-μm distances, were recording the potential changes with DC-coupled amplifiers in CA1 and dentate gyrus (DG) of one hemisphere. Seizures and spreading depression were provoked by repetitive stimulation of different afferent pathways. Seizures always began in DG before CA1, regardless of the pathway stimulated. Tonic seizures were associated with a sustained negative potential shift that was largest in the cell body layers. Current source density was computed from these recordings and confirmed the presence of a current sink limited to the cell body layer throughout the duration of electrographic seizures. Spreading depression was associated with a very large sink located in the layer of apical dendrites, maximal among the proximal segment of dendrites, to which the cell body layer served as a source. We conclude that seizures are associated with an inward current in neuron cell bodies, probably flowing through membrane channels of as yet no know physiological function.     

Cerebral hemorrhages and infarcts following use of cocaine

With increasing abuse of cocaine and purity of this drug, the incidence of strokes in relatively young people is also increasing. We describe two patients, one 29 years, the other one 33 years old. Both were well-known cocaine users. The first patient presented with an intracranial haemorrhage; the computed tomography of the brain is shown. The second patient showed a cerebral ischaemic infarction. The most frequent vascular complications are described. The physiological backgrounds of cerebrovascular accidents are given. Use of cocaine can be suggested by the presence of benzoylecgonine in urine samples.     

Precision and accuracy of a HPLC method for measurement of fecal porphyrin concentrations.

We studied precision and accuracy of a HPLC method for determination of porphyrins in feces. A commercial standard solution appeared to contain less coproporphyrin (15%) than stated by the manufacturer. The between-batch coefficients of variation were often below 15% and were higher than the within-batch coefficients. The precision of porphyrin measurements was not influenced by the type of porphyria. Recoveries of added coproporphyrin and protoporphyrin were 90% and 108%; coefficients of variation were 6% and 19%, respectively.     

Kindling increases the K -evoked Ca -dependent release of endogenous GABA in area CA1 of rat hippocampus

The release of endogenous amino acids from hippocampal CA1 subslices under basal conditions and the release evoked by high potassium (50 mM K⁺) depolarization was studied during kindling epileptogenesis. Emphasis was put on the release of the amino acid neurotransmitters γ-aminobutyric acid (GABA) and glutamate. Kindling was induced by tetanic stimulation of the Schaffer-collaterals/commissural fibers of the dorsal hippocampus of the rat. The calcium-dependent GABA release in the presence of high K⁺ was significantly increased (40–46%) in fully kindled animals, 24 h after the last seizure, in comparison to controls. At long-term, 28 days after the last seizure, the calcium-dependent GABA release was still significantly increased (45–49%). An increased release of GABA in kindled animals was still found when GABA uptake was blocked by nipecotic acid. In contrast, no significant alterations were encountered in the basal or high potassium induced release of the excitatory amino acids aspartate and glutamate. These results suggest that kindling epileptogenesis is accompanied by a specific and long-lasting enhancement of GABA exocytosis which may lead to a desensitization of the GABA receptor, and thus determine the increase of seizure sensitivity.