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Journal Article 2010; 31(1): 63-66 PubMed PMID: 20150869 Citation  Keywords:  Case-Control Studies, Cystinyl Aminopeptidase:blood, Down-Regulation, Enzyme Activation, Female, Gestational Age, Humans, Pre-Eclampsia:blood, Pregnancy, Premature Birth:blood, Severity of Illness Index, Term Birth:blood,.   

OBJECTIVE: Placental Leucine Aminopeptiadse (P-LAP) also known as oxytocinase, is secreted by syncytiotrophoblast and increases gradually during pregnancy until delivery. It is a regulator of uterine contractions, of vascular resistance and of volume of the retroplacental blood pool. Recently, it was shown that it could also regulate metalloproteinase 9 activity and thus, invasiveness of trophoblastic cells. Since development of preeclampsia could be initiated by decreased cytotrophoblastic invasion of spiral arterioles and a reduced uteroplacental perfusion, we speculate that circulating P-LAP activity could be decreased during preeclampsia.r />r /> MATERIALS AND METHODS: Case-control study was evaluated in 84 women. P-LAP activity was measured in n=51 healthy pregnant women at term, and compared with n=16 normotensive women delivering preterm and n=17 women diagnosed with pre-eclampsia. P-LAP activity was determined by colorimetry in plasma samples using L-Leucine-p-nitroanilide as substrate.r />r /> RESULTS: P-LAP activity was significantly lower in sera of preeclamptic women (0.91+/-0.122 mDO/min) as compared to normotensive controls (1.41+/-0.103 mDO/min; p=0.003) irrespective of time of delivery.r />r /> CONCLUSIONS: These findings confirm the probable involvement of P-LAP in trophoblast invasion and development of preeclampsia....

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Journal Article 2010; 31(1): 155-160 PubMed PMID: 20150868 Citation  Keywords:  Aged, Aged, 80 and over, Biomarkers:analysis, Body Mass Index, Bone Density, Bone Remodeling:physiology, Bone and Bones:metabolism, Calcium:analysis, Female, Humans, Leptin:blood, Male, Middle Aged, Osteoporosis:blood,.   

OBJECTIVE: Clinical data have suggested that obesity protects against osteoporosis. Leptin, mainly secreted by white adipose tissue, might be involved by mediating an effect on bone metabolism. This study was conducted to investigate a possible relationship of leptin and bone turn-over in postmenopausal women with osteoporosis.r />r /> METHODS: We measured bone mineral density (BMD), serum leptin levels and markers of bone metabolism, including osteocalcin and cross-laps in 44 patients with osteoporosis. The main group consisted of 32 postmenopausal women.r />r /> RESULTS: Mean serum leptin was 13.1 microg/L and showed no statistically significant difference to the levels measured in a collective of normal persons adjusted for age and BMI. When related to serum cross-laps as markers of bone resorption, a positive correlation (p<0.05) was observed, whereas no correlation with osteocalcin could be seen.r />r /> CONCLUSIONS: A dual control of bone formation by leptin is assumed: This involves local mechanisms acting on osteoblasts and a central inhibitory effect on bone metabolism via a hypothalamic relay. Our data indicate that the net effect of circulating leptin may cause bone loss and is significantly related to high-turnover serum bone markers, at least in postmenopausal women with osteoporosis....

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Journal Article 2010; 31(1): 4-10 PubMed PMID: 20150867 Citation  Keywords:  Alcoholism:genetics, Child, Developmental Disabilities:genetics, Feeding and Eating Disorders:genetics, Genetic Predisposition to Disease, Humans, Mental Disorders:genetics, Mood Disorders:genetics, Mutant Proteins:physiology, Polymorphism, Genetic:physio.   

: Both serotonin and the serotonin transporter, which transports the neurotransmitter serotonin from synaptic spaces into presynaptic neurons, play an important role in the pathophysiology of several psychiatric disorders. Mutations associated with the serotonin transporter gene may result in changes in serotonin transporter function. The serotonin transporter gene promoter variant, consisting of a long (L) and a short (S) variant, is one of the major factors which contribute to the etiology of many psychiatric disorders. In this regard, many studies have been published on association of this variant with various psychiatric disorders. This repeat length variant in the promoter region of this gene has been shown to affect the rate of serotonin uptake and may play a role in post-traumatic stress disorder and depression-susceptibility in people experiencing emotional trauma. Associations between a functional variant in the serotonin transporter anxiety-related personality traits were found, as well as the risk of developing depression, alcoholism or suicidal behavior. Understanding of possible associations of these variants and psychiatric disorders would bring progress in principles and treatment of many disorders....

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Clinical Trial 2010; 31(1): 92-96 PubMed PMID: 20150866 Citation  Keywords:  Adolescent, Biological Clocks:physiology, Circadian Rhythm:physiology, Eyeglasses, Female, Humans, Light, Lighting:adverse effects, Male, Melatonin:metabolism, Population, Radio Waves, Schools, Sleep Disorders, Circadian Rhythm:etiology, Students, Time Fa.   

OBJECTIVE: Circadian timing affects sleep onset. Delayed sleep onset can reduce sleep duration in adolescents required to awake early for a fixed school schedule. The absence of short-wavelength ("blue") morning light, which helps entrain the circadian system, can hypothetically delay sleep onset and decrease sleep duration in adolescents. The goal of this study was to investigate whether removal of short-wavelength light during the morning hours delayed the onset of melatonin in young adults.r />r /> METHODS: Dim light melatonin onset (DLMO) was measured in eleven 8th-grade students before and after wearing orange glasses, which removed short-wavelength light, for a five-day school week.r />r /> RESULTS: DLMO was significantly delayed (30 minutes) after the five-day intervention, demonstrating that short-wavelength light exposure during the day can be important for advancing circadian rhythms in students.r />r /> CONCLUSIONS: Lack of short-wavelength light in the morning has been shown to delay the circadian clock in controlled laboratory conditions. The results presented here are the first to show, outside laboratory conditions, that removal of short-wavelength light in the morning hours can delay DLMO in 8th-grade students. These field data, consistent with results from controlled laboratory studies, are directly relevant to lighting practice in schools....

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Journal Article 2010; 31(1): 137-146 PubMed PMID: 20150865 Citation  Keywords:  Acetylcysteine:pharmacology, Ambroxol:pharmacology, Animals, Antioxidants:pharmacology, Antithyroid Agents:administration & dosage, Drug Evaluation, Preclinical, Free Radical Scavengers:pharmacology, Injections, Intraperitoneal, Lipid Peroxidation:drug ef.   

OBJECTIVE: A possible role of antioxidants in thyreotoxicosis was investigated. We examined the parameters of lipid peroxidation (LPO): conjugated dienes (CD), malondialdehyde (MDA), Schiff bases (SB) in lung homogenates of male Wistar rats.r />r /> METHODS: Two control groups were created: Group 1 - intact animals and Group 2 - animals injected with 0,9% NaCl. In Experiment I, the animals received L-thyroxin (LT4) i.p. (Groups 3-7). After one week the rats received additionally: Group 4 - melatonin (MEL); Group 5 - propylthiouracil (PTU); Group 6 - Ambroxol (AMB); Group 7 - N-acetylocysteine (NAC). In Experiment II, the animals received only antioxidants.r />r /> RESULTS: In Experiment I, we noticed a significantly higher MDA and SB level in Group 2, compared to that in Group 1. Moreover, we observed a significantly higher MDA and SB level in Group 3, vs. that in Group 1, but SB level was lower in Group 3 than in Group 2. Melatonin, PTU and NAC reduced CD; PTU, AMB diminished MDA and MEL, AMB lowered SB levels as compared to Group 3. In Experiment II, we observed significantly higher MDA and SB level in Group 2, vs. that in Group 1. Melatonin, AMB and NAC decreased MDA and SB level, when compared to Group 2 but PTU elevated MDA and SB level vs. that in Group 1.r />r /> CONCLUSIONS: 1) L-T4 suppresses LPO, 2) MEL, AMB and NAC protect against LPO, 3) PTU is an antioxidant in thyreotoxicosis, however, when administered alone, it enhances LPO, 4) stress accelerate LPO....

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Clinical Trial 2010; 31(1): 161-167 PubMed PMID: 20150864 Citation  Keywords:  Adult, Brain Mapping:methods, Cerebral Cortex:metabolism, Cystine:analogs & derivatives, Estrogen Replacement Therapy, Female, Humans, Hypothyroidism:diagnosis, Male, Neuropsychological Tests, Prognosis, Severity of Illness Index, Technetium:chemistry, Th.   

OBJECTIVE: The purpose of this study was to correlate hypothyroid-related symptomatology with regional cerebral blood flow (rCBF) during hypothyroidism.r />r /> MATERIALS AND METHODS: Nine thyroidectomized patients underwent neuropsychological testing and single photon emission computed tomography (SPECT) of their brains with technetium-99m (Tc-99m) ethyl cysteinate dimer (ECD), a lipophilic cerebral blood flow radiotracer, while hypothyroid, and again following thyroid hormone replacement. Neuropsychological test scores and TSH levels while hypothyroid were correlated with rCBF in hypothyroid-affected areas of the brain.r />r /> RESULTS: Correlations were found during hypothyroidism between the noted parameters and ECD radiotracer accumulation in the following respective regions, all of which demonstrated hypothyroid-related cerebral blood flow (CBF) aberrations: TSH and left middle occipital gyrus; psychomotor performance speed and left precentral gyrus; and depression and right middle frontal gyrus, left middle frontal gyrus, right insula, and left thalamus.r />r /> CONCLUSIONS: Severity of psychomotor impairment and depression, and TSH level during hypothyroidism appeared to correlate with CBF to brain regions associated with motor activity, mood and vision, respectively; and previously shown to manifest significantly altered rCBF during hypothyroidism....

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Journal Article 2010; 31(1): 1-3 PubMed PMID: 20150863 Citation  Keywords:  Biological Clocks:physiology, Biomedical Research:standards, Causality, Chronobiology Disorders:complications, Humans, Models, Theoretical, Neoplasms:epidemiology, Risk Factors,.   

: A cascade of investigations into the validity of the chronodisruption-cancer theory (CD-CT), proposed 2008 in Neuroendocrinology Letters as a synthesis of abundant experimental and tantalizing - but still limited - epidemiological data, can be expected in coming years. In view of the possible public health relevance of the suggested links between chronodisruption, defined as the disruption of the temporal organization or order of biological rhythmicity over days and seasons, and the development of disease, including cancer, we provide practical aspects which should be considered for the planning, conduct and the very interpretation of such studies. The interrelated considerations address two facets: first, the critical necessity of causal clarification can be evinced appropriately by Poole's earlier contribution to the Journal. Researchers into the validity of the CD-CT should certainly consider Poole's 2002 illustration via causal graphs for shift work, light at night and breast cancer of the subtleties that can arise in the use of exposure surrogates of different kinds. Second, we emphasize the importance of considering the Zeitgeber multiplicity to avoid causal reductionism in epidemiologic - but also other - chronodisruption research....

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Journal Article 2001; 22(1): 53-73 PubMed PMID: 11393163 Citation  Keywords:  Adrenal Glands:physiology, Animals, Biological Clocks, Blood Pressure:physiology, Chronobiology Disorders:physiopathology, Chronobiology Phenomena, Chronotherapy, Circadian Rhythm:physiology, Drug Administration Schedule, Genomics, Homeostasis, Humans, Pi.   

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