A Multiplatform Inversion Estimation of Statewide and Regional Methane Emissions in California during 2014-2016.

California methane (CH4) emissions are quantified for three years from two tower networks and one aircraft campaign. We used backward trajectory simulations and a mesoscale Bayesian inverse model, initialized by three inventories, to achieve the emission quantification. Results show total statewide CH4 emissions of 2.05 ± 0.26 (at 95% confidence) Tg/yr, which is 1.14 to 1.47 times greater than the anthropogenic emission estimates by California Air Resource Board (CARB). Some of differences could be biogenic emissions, superemitter point sources, and other episodic emissions which may not be completely included in the CARB inventory. San Joaquin Valley (SJV) has the largest CH4 emissions (0.94 ± 0.18 Tg/yr), followed by the South Coast Air Basin, the Sacramento Valley, and the San Francisco Bay Area at 0.39 ± 0.18, 0.21 ± 0.04, and 0.16 ± 0.05 Tg/yr, respectively. The dairy and oil/gas production sources in the SJV contribute 0.44 ± 0.36 and 0.22 ± 0.23 Tg CH4/yr, respectively. This study has important policy implications for regulatory programs, as it provides a thorough multiyear evaluation of the emissions inventory using independent atmospheric measurements and investigates the utility of a complementary multiplatform approach in understanding the spatial and temporal patterns of CH4 emissions in the state and identifies opportunities for the expansion and applications of the monitoring network.

Effect of sonic versus manual supervised toothbrushing on both clinical and biochemical profiles of patients with desquamative gingivitis associated with oral lichen planus: A randomized controlled trial.

OBJECTIVES: The aim of this randomized, parallel-design, clinical trial was to investigate the effectiveness of an intensive plaque control programme with sonic versus manual toothbrushing on clinical outcomes and gingival crevicular fluid (GCF) levels of matrix metalloproteinases (MMP) in desquamative gingivitis (DG) patients. METHODS: A total of 32 patients affected by DG secondary to oral lichen planus (OLP) were consecutively recruited and randomly assigned to a test (n = 16) and control (n = 16) group. Both groups were enrolled in an intensive control programme comprising supragingival scaling and polishing, and brush-specific instructions for a period of 8 weeks. The treatment of interest (test) was the use of a sonic-powered toothbrush, and the standard treatment (control) was the utilization of a soft-bristle manual toothbrush for twice-daily home oral hygiene procedures. Periodontal parameters, patient-centred outcomes, MMP-1 and MMP-9 GCF levels were evaluated at baseline and 8 weeks after starting the programme. RESULTS: The plaque control programme resulted in statistically significant reduction in periodontal parameters with consequent improvement in the clinical features, painful symptoms and severity of DG lesions in both groups (all P < 0.001). When a sonic toothbrush was used, there was a more significant decrease in clinical indices, mucosal disease scores and GCF levels of MMP-1 and MMP-9. CONCLUSIONS: This clinical trial reported the effectiveness of a combined protocol based on professional oral hygiene and supervised toothbrushing in OLP patients with DG. The daily use of a sonic toothbrush would seem to perform better in the short term.

Biomarker levels in gingival crevicular fluid of generalized aggressive periodontitis patients after non-surgical periodontal treatment.

OBJECTIVES: The aim of this study was to assess the effects of non-surgical periodontal treatment on gingival crevicular fluid (GCF) cytokines in patients with generalized aggressive periodontitis (GAgP), in relation to clinical parameters. MATERIALS AND METHODS: Data were obtained from 16 GAgP patients and 15 periodontally healthy controls. Periodontal parameters and GCF biomarker levels were evaluated at baseline and repeated 3 and 6 months after treatment for GAgP subjects. Moderate and deep pocket sites were analyzed separately. The amount of interleukin (IL)-1ß, IL-9, tumor necrosis factor (TNF)-α, platelet-derived growth factor (PDGF-bb), and vascular endothelial growth factor (VEGF) were measured using a highly specific and sensitive multiplex bead immunoassay. RESULTS: At baseline, cytokine levels in the moderate and deep pocket sites of GAgP patients were higher than those of the healthy control sites. In GAgP group, periodontal treatment led to improvement in all examined clinical parameters and resulted in a statistically significant reduction in the total amounts of IL-1ß, VEGF, and TNF-α, in comparison to baseline, already 3 months after therapy in both moderate and deep pocket sites and of PDGF-bb in deep sites (p < 0.01). At the concentration level, only IL-1ß and VEGF were affected. CONCLUSION: Non-surgical treatment of GAgP provided significant clinical benefits leading to a marked decrease in the GCF levels of some pro-inflammatory and pro-angiogenic cytokines, but not of IL-9 and PDGF-bb. CLINICAL RELEVANCE: Although the periodontal therapy successfully decreased clinical signs of inflammation, the GCF levels of some inflammatory cytokines were still elevated.

Improved Mechanistic Understanding of Natural Gas Methane Emissions from Spatially Resolved Aircraft Measurements.

Divergence in recent oil and gas related methane emission estimates between aircraft studies (basin total for a midday window) and emissions inventories (annualized regional and national statistics) indicate the need for better understanding the experimental design, including temporal and spatial alignment and interpretation of results. Our aircraft-based methane emission estimates in a major U.S. shale gas basin resolved from west to east show (i) similar spatial distributions for 2 days, (ii) strong spatial correlations with reported NG production (R2 = 0.75) and active gas well pad count (R2 = 0.81), and (iii) 2× higher emissions in the western half (normalized by gas production) despite relatively homogeneous dry gas and well characteristics. Operator reported hourly activity data show that midday episodic emissions from manual liquid unloadings (a routine operation in this basin and elsewhere) could explain ∼1/3 of the total emissions detected midday by the aircraft and ∼2/3 of the west-east difference in emissions. The 22% emission difference between both days further emphasizes that episodic sources can substantially impact midday methane emissions and that aircraft may detect daily peak emissions rather than daily averages that are generally employed in emissions inventories. While the aircraft approach is valid, quantitative, and independent, our study sheds new light on the interpretation of previous basin scale aircraft studies, and provides an improved mechanistic understanding of oil and gas related methane emissions.

Detector developments at DESY.

With the increased brilliance of state-of-the-art synchrotron radiation sources and the advent of free-electron lasers (FELs) enabling revolutionary science with EUV to X-ray photons comes an urgent need for suitable photon imaging detectors. Requirements include high frame rates, very large dynamic range, single-photon sensitivity with low probability of false positives and (multi)-megapixels. At DESY, one ongoing development project - in collaboration with RAL/STFC, Elettra Sincrotrone Trieste, Diamond, and Pohang Accelerator Laboratory - is the CMOS-based soft X-ray imager PERCIVAL. PERCIVAL is a monolithic active-pixel sensor back-thinned to access its primary energy range of 250 eV to 1 keV with target efficiencies above 90%. According to preliminary specifications, the roughly 10 cm × 10 cm, 3.5k × 3.7k monolithic sensor will operate at frame rates up to 120 Hz (commensurate with most FELs) and use multiple gains within 27 µm pixels to measure 1 to ∼100000 (500 eV) simultaneously arriving photons. DESY is also leading the development of the AGIPD, a high-speed detector based on hybrid pixel technology intended for use at the European XFEL. This system is being developed in collaboration with PSI, University of Hamburg, and University of Bonn. The AGIPD allows single-pulse imaging at 4.5 MHz frame rate into a 352-frame buffer, with a dynamic range allowing single-photon detection and detection of more than 10000 photons at 12.4 keV in the same image. Modules of 65k pixels each are configured to make up (multi)megapixel cameras. This review describes the AGIPD and the PERCIVAL concepts and systems, including some recent results and a summary of their current status. It also gives a short overview over other FEL-relevant developments where the Photon Science Detector Group at DESY is involved.

In male rats with concurrent iron and (n-3) fatty acid deficiency, provision of either iron or (n-3) fatty acids alone alters monoamine metabolism and exacerbates the cognitive deficits associated with combined deficiency.

Concurrent deficiencies of iron (Fe) (ID) and (n-3) fatty acids [(n-3)FAD)] in rats can alter brain monoamine pathways and impair learning and memory. We examined whether repletion with Fe and DHA/EPA, alone and in combination, corrects the deficits in brain monoamine activity (by measuring monoamines and related gene expression) and spatial working and reference memory [by Morris water maze (MWM) testing] associated with deficiency. Using a 2 × 2 design, male rats with concurrent ID and (n-3)FAD [ID+(n-3)FAD] were fed an Fe+DHA/EPA, Fe+(n-3)FAD, ID+DHA/EPA, or ID+(n-3)FAD diet for 5 wk [postnatal d 56-91]. Biochemical measures and MWM performance after repletion were compared to age-matched control rats. The provision of Fe in combination with DHA/EPA synergistically increased Fe concentrations in the olfactory bulb (OB) (Fe x DHA/EPA interaction). Similarly, provision of DHA/EPA in combination with Fe resulted in higher brain DHA concentrations than provision of DHA alone in the frontal cortex (FC) and OB (P < 0.05). Dopamine (DA) receptor D1 was upregulated in the hippocampus of Fe+DHA/EPA rats (fold-change = 1.25; P < 0.05) and there were significant Fe x DHA/EPA interactions on serotonin (5-HT) in the OB and on the DA metabolite dihydroxyphenylacetic acid in the FC and striatum. Working memory performance was impaired in ID+DHA/EPA rats compared with controls (P < 0.05). In the reference memory task, Fe+DHA/EPA improved learning behavior, but Fe or DHA/EPA alone did not. These findings suggest that feeding either Fe or DHA/EPA alone to adult rats with both ID and (n-3)FAD affects the DA and 5-HT pathways differently than combined repletion and exacerbates the cognitive deficits associated with combined deficiency.

Combined deficiency of iron and (n-3) fatty acids in male rats disrupts brain monoamine metabolism and produces greater memory deficits than iron deficiency or (n-3) fatty acid deficiency alone.

Deficiencies of iron (Fe) (ID) and (n-3) fatty acids (FA) [(n-3)FAD] may impair brain development and function through shared mechanisms. However, little is known about the potential interactions between these 2 common deficiencies. We studied the effects of ID and (n-3)FAD, alone and in combination, on brain monoamine pathways (by measuring monoamines and related gene expression) and spatial working and reference memory (by Morris water maze testing). Using a 2 × 2 design, male rats were fed an ID, (n-3)FAD, ID+(n-3)FAD, or control diet for 5 wk postweaning (postnatal d 21-56) after (n-3)FAD had been induced over 2 generations. The (n-3)FAD and ID diets decreased brain (n-3) FA by 70-76% and Fe by 20-32%, respectively. ID and (n-3)FAD significantly increased dopamine (DA) concentrations in the olfactory bulb (OB) and striatum, with an additive 1- to 2-fold increase in ID+(n-3)FAD rats compared with controls (P < 0.05). ID decreased serotonin (5-HT) levels in OB, with a significant decrease in ID+(n-3)FAD rats. Furthermore, norepinephrine concentrations were increased 2-fold in the frontal cortex (FC) of (n-3)FAD rats (P < 0.05). Dopa decarboxylase was downregulated in the hippocampus of ID and ID+(n-3)FAD rats (fold-change = -1.33; P < 0.05). ID and (n-3)FAD significantly impaired working memory performance and the impairment positively correlated with DA concentrations in FC (r = 0.39; P = 0.026). Reference memory was impaired in the ID+(n-3)FAD rats (P < 0.05) and was negatively associated with 5-HT in FC (r = -0.42; P = 0.018). These results suggest that the combined deficiencies of Fe and (n-3) FA disrupt brain monoamine metabolism and produce greater deficits in reference memory than ID or (n-3)FAD alone.

Recognition and treatment of peri-implant mucositis: Do we have the right perception? A structured review.

Peri-implant mucositis is a common inflammatory lesion of the soft tissues surrounding endosseous implants, with no loss of the supporting bone. Its prevention or early diagnosis are vital for dental implant success.The aim of this review was to investigate knowledge strengths and gaps in clinicians' perceptions of periimplant mucositis prevalence and evidence for successful treatment.A literature search for articles published until 2020, reporting on the prevalence of peri-implant mucositis and its treatment was performed in standard online databases. The inclusion criteria were as follows: studies in English; studies with an available abstract; studies on humans with at least 1 dental implant; and studies reporting on the prevalence and/or treatment of peri-implant mucositis. Sixty-five studies fulfilled the inclusion criteria. The included papers were analyzed to identify data on the prevalence and treatment of peri-implant mucositis. The prevalence statistics for peri-implant mucositis had wide ranges in both the patient-based (PB) analysis and the implant-based (IB) analysis; the possible reasons for these wide ranges are discussed. Treatment methods for peri-implant mucositis were analyzed individually and compared to the management of gingivitis.It was determined that the currently available information on the prevalence rates and the standardized therapeutic protocols for peri-implant mucositis are insufficient. Since the mean gingivitis and peri-implant mucositis prevalence rates in the PB analysis were similar, it is possible that peri-implant mucositis is underestimated due to variables related to implant rehabilitation itself.

Lower extremity performance measures predict long-term prognosis in older patients hospitalized for heart failure.

BACKGROUND: In older heart failure (HF) patients, survival depends on the severity of their cardiac condition and on their functional status. Lower extremity performance, assessed with the Short Physical Performance Battery (SPPB), predicts survival in older persons, both in epidemiologic and clinical settings. We evaluated whether SPPB predicts long-term survival in older subjects hospitalized for HF, independent of traditional measures of HF severity. METHODS AND RESULTS: Subjects aged 65+ years were enrolled on discharge after hospitalization for decompensated HF. Participants underwent echocardiography, comprehensive geriatric assessment, and SPPB. Cox proportional hazards regression models were used to predict survival over a 30-month follow-up. Of 157 participants (mean age 80 years, range 65-101; 50% men), 61 died. After adjustment for potential confounders, including demographics, ejection fraction, New York Heart Association classification, and comorbidity, we found a graded independent association between SBBP score and mortality risk: compared with an SPPB score of 9-12, scores of 0, 1-4, and 5-8 were associated with hazard ratios (HR) and 95% confidence interval (CI) of death of 6.06 (2.19-16.76), 4.78 (1.63-14.02), and 1.95 (0.67-5.70), respectively. CONCLUSIONS: SPPB is an independent predictor of long-term survival of older subjects hospitalized for decompensated HF.

Self-Perception of Periodontal Health and Associated Factors: A Cross-Sectional Population-Based Study.

The aim of this cross-sectional study was to explore sociodemographic, behavioral, and clinical factors associated with self-awareness of periodontal health. Data were collected from a representative sample of 736 adults (25-75 years old) in a city of Northern Italy who self-assessed gingival bleeding, oral malodor, and tooth mobility in a questionnaire and who underwent clinical periodontal examination and organoleptic evaluation. Approximately 50% of the subjects were aware of their actual gingival health status and oral odor. The logistic regression analysis revealed that females presented higher odds of correctly perceiving their gingival conditions and mouth odor, while those who were older and smokers had a greater probability of being less objective in reporting them. Tooth type and position in the dental arches were positively associated with self-perception of tooth mobility. These findings reflected a low level of self-awareness that may influence oral care-seeking behavior. Subjects may be unconcerned about their periodontal health condition or lack enough knowledge to be aware of it. This points to the need for planning strategies to improve education and knowledge about periodontal health, which, by enhancing self-perception of periodontal symptoms, could help everyone to seek treatment in the initial stage of the disease.

Gingival Crevicular Fluid Cytokines in Moderate and Deep Sites of Stage III Periodontitis Patients in Different Rates of Clinical Progression.

Clinical criteria are inappropriate to measure the degree of susceptibility to progression of periodontal damage. Thus, the aim of this study was to assess whether gingival crevicular fluid (GCF) levels of cytokines could discriminate patients suffering from stage III periodontitis with moderate (Grade B) and rapid rates of progression (Grade C) prior to and 6 months after non-surgical periodontal treatment. GCF samples were obtained from moderate and deep sites of 20 patients diagnosed as Grade B and 20 patients as grade C stage III periodontitis and analyzed for interleukin (IL)-1ß, IL-9, tumor necrosis factor (TNF)-α, and vascular endothelial growth factor (VEGF) using a high-sensitivity Bio-Plex Suspension Array System. At baseline, higher IL-1ß but lower IL-9 GCF levels were observed in moderate sites of the grade C compared to the grade B group. In spite of comparable clinical improvement, this difference maintained after treatment, suggesting a residual pro-inflammatory state. In deep sites, no differences were observed between periodontitis groups except for VEGF levels that decreased more in Grade B periodontitis at 6 months post-therapy. A mathematical model was constructed to identify Grade C periodontitis patients based on the subjects' GCF levels of IL-1ß and IL-9, which achieved an area under the receiver-operating characteristic (ROC) curve of 0.94. This study can contribute to the early assessment of risk of future breakdown in periodontitis patients.

One-year clinical outcomes following non-surgical treatment of peri-implant mucositis with adjunctive diode laser application.

BACKGROUND: Limited information is available on the application of diode laser in the treatment of peri-implant diseases. The aim of this study was to investigate the clinical efficacy of the adjunctive application of diode laser in the non-surgical treatment of peri-implant mucositis during a 12-month follow-up period. METHODS: The sample was composed of 73 systemically healthy patients with one implant diagnosed with peri-implant mucositis (bleeding on probing [BoP] with no loss of supporting bone). Implants were randomly assigned to mechanical debridement with hand and powered instruments and 980-nm diode laser application (test group, N.=38) or mechanical debridement alone (control group, N.=35). At the completion of active treatment patients were included in a periodontal maintenance program. Recalls were provided every three months in both treatment groups for reinforcement in oral hygiene instructions and professional implant cleaning with rubber cups. Baseline parameters were repeated at 3 and 12 months postoperatively. RESULTS: Intragroup analysis showed that plaque index, BoP and probing depth presented statistically significant improvements when compared with baseline values (all P<0.001). No statistically significant difference in clinical outcomes was observed between treatment groups at each time point. At 12 months no significant difference in the percentage of sites showing BoP resolution was observed between test (60.9%) and control treatment (52.6%), as well. CONCLUSIONS: Based on the present results, the adjunct use of diode laser showed little but not statistically significant additional benefits in the treatment of peri-implant mucositis after an observation period of one year.

A history of iron deficiency anemia during infancy alters brain monoamine activity later in juvenile monkeys.

Both during and after a period of iron deficiency (ID), iron-dependent neural processes are affected, which raises the potential concern that the anemia commonly experienced by many growing infants could have a protracted effect on the developing brain. To further investigate the effects of ID on the immature brain, 49 infant rhesus monkeys were evaluated across the first year of life. The mothers, and subsequently the infants after weaning, were maintained on a standardized diet containing 180 mg/kg of iron and were not provided other iron-rich foods as treats or supplements. As the infants grew, they were all screened with hematological tests, which documented that 16 (33.3%) became markedly ID between 4 and 8 months of age. During this anemic period and subsequently at 1 year of age, cerebrospinal fluid (CSF) specimens were collected to compare monoamine activity in the ID and iron-sufficient infants. Monoamine neurotransmitters and metabolite levels were normal at 4 and 8 months of age, but by 1 year the formerly anemic monkeys had significantly lower dopamine and significantly higher norepinephrine levels. These findings indicate that ID can affect the developmental trajectory of these two important neurotransmitter systems, which are associated with emotionality and behavioral performance, and further that the impact in the young monkey was most evident during the period of recovery.

Iron deficiency alters dopamine uptake and response to L-DOPA injection in Sprague-Dawley rats.

Iron deficiency (ID) disrupts brain dopamine (DA) and norepinephrine (NE) metabolism including functioning of monoamine transporters and receptors. We employed caudate microdialysis and no net flux (NNF) in post-weaning rats to determine if ID decreased the extraction fraction (E(d)). Five micromolar quinpirole, a dopamine D(2) receptor agonist, resulted in 80% decrease in extracellular DA and 45% higher E(d) in control animals. The D(2) agonist had no effect on E(d) in ID animals despite a reduction in basal DA. DAT mRNA levels were reduced by 58% with ID, while DAT protein in ventral midbrain and caudate and membrane associated DAT were also reduced by ID. Carbidopa/l-DOPA was administered to determine if elevated extracellular DA in ID was due to increased release. The DA response to l-DOPA in ID rats was 50% smaller and delayed, whereas the NE response was threefold higher. The caudate concentration of NE was also elevated in ID. Elevated dopamine-beta-hydroxylase activity in ID provides a tentative explanation for the increased NE response to l-DOPA. These experiments provide new evidence that ID results in altered synthesis and functioning of DAT and perhaps suggests some compensatory changes in NE metabolism.

Filtration disrupts synaptosomes during radiochemical analysis of serotonin uptake: comparison with chronoamperometry in SERT knockout mice.

Radiochemical methods have failed to reveal decreases in synaptosomal serotonin uptake in mice lacking one functional copy of the serotonin transporter (SERT) gene. By contrast, uptake rates determined by chronoamperometry in synaptosomes from SERT+/- mice show gene-related reductions. We revisited [(3)H]5-HT uptake in SERT knockout mice to determine the effects of inclusion of O(2) in the incubation buffer on the kinetic parameters obtained by this method. In oxygenated synaptosomes prepared from frontal cortex and striatum, modest 25 and 35% reductions in radiolabeled 5-HT uptake were detected in SERT+/- versus SERT+/+ mice. However, even in the presence of O(2), no differences in [(3)H]5-HT uptake were detected between SERT+/- and SERT+/+ mice in brain stem in contrast to 60% reductions determined by chronoamperometry. Moreover, while inclusion of O(2) modestly increased the rates of [(3)H]5-HT uptake, rates determined by chronoamperometry in the presence of O(2) were 40-fold greater than those determined radiochemically. We present evidence that the filtration process used in the radiochemical method leads to substantial loss of transported 5-HT resulting in lower apparent uptake rates. These findings explain the relative insensitivity of radiochemical methods for determining biologically important alterations in uptake such as those occurring between SERT+/- and SERT+/+ mice and in response to O(2).

Acoustic startle response is disrupted in iron-deficient rats.

Diurnal effects on motor control are evident in the human disease of Restless Leg Syndrome (RLS), which is purported to be linked to brain iron deficiency as well as alterations in dopaminergic systems. Thus, we explored the relationship between daily rhythms, the onset of motor dysregulation and brain iron deficiency in an animal model of iron deficiency. Male and female weanling Sprague-Dawley rats consuming control (CN) or iron-deficient (ID) diets were examined weekly for acoustic startle response (ASR) and prepulse inhibition (PPI) for a 5-week period. Iron deficiency reduced the magnitude, but not timing, of the ASR at specific time points. ASR was elevated 60% at the onset of the dark cycle relative to the median of the light cycle in male CN and ID rats. The respective elevation was 400% and 150% in female CN and ID rats during the first 2 weeks of testing. The diurnal cycle of ASR response was attenuated by 3 weeks of testing in both dietary treatment groups. PPI was not affected by iron deficiency, sex, diurnal cycle or the interaction between these factors. These results thus demonstrate that iron deficiency moderately alters ASR signaling although the inhibitory pathways of ASR do not appear to be affected.

Age and comorbidity in acute myocardial infarction: a report from the AMI-Florence Italian registry.

A total of 930 cases of ST-segment elevation myocardial infarction were prospectively recorded in the Florence health district. Factors influencing survival or those associated with use of revascularization (percutaneous coronary intervention, 91%) were identified through multivariate analyses (Cox and logistic regression, respectively). The independent protective effect of coronary reperfusion therapy (CRT) was evident at 36 months (39% reduction in the risk of death). After adjusting for all multivariate predictors, CRT use was 63% less likely at age 85 years and older than at under 65 years (p<0.001). Since beyond advancing age, comorbidity appeared to be associated with a reduced chance of CRT, three chronic comorbidity score categories were calculated using information on past medical history. Increased 1-year mortality in patients with higher comorbidity score categories derives, at least in part, from underutilization of CRT. Results confirm that although they might potentially benefit from CRT during ST-segment elevation myocardial infarction, older and frail patients are excluded from CRT, even when eligible.

Low brain iron effects and reversibility on striatal dopamine dynamics.

Iron deficiency (ID) in rodents leads to decreased ventral midbrain (VMB) iron concentrations and to changes in the dopamine (DA) system that mimic many of the dopaminergic changes seen in RLS patient where low substantia nigra iron is a known pathology of the disease. The ID-rodent model, therefore, has been used to explore the effects that low VMB iron can have on striatal DA dynamics with the hopes of better understanding the nature of iron-dopamine interaction in Restless Legs Syndrome (RLS). Using a post-weaning, diet-induced, ID condition in rats, the No-Net-Flux microdialysis technique was used to examine the effect of ID on striatal DA dynamics and it reversibility with acute infusion of physiological concentrations of iron into the VMB. This study replicated prior findings by showing that the ID condition is associated with increased extracellular striatal DA, reduced striatal DA uptake, and blunted DA-2-receptor-agonist feedback enhancement of striatal DA uptake. Despite the increase in extracellular striatal DA, intracellular striatal DA, as determined in tissue homogenates, was decrease in the ID rat. The study's key finding was that an infusion of physiological concentrations of iron into the VMB reversed the ID-induced increase in extracellular striatal DA and the ID-induced decrease in intracellular striatal DA but had no effect on the ID-induced changes in DA uptake or on the blunted DA-uptake response to quinpirole. In summary, the ID-rodent model provides highly reproducible changes in striatal DA dynamics that remarkably parallel dopaminergic changes seen in RLS patients. Some but not all of these ID-induced changes in striatal DA dynamics were reversible with physiological increases in VMB iron. The small changes in VMB iron induced by iron infusion likely represent biologically relevant changes in the non-transferrin-bound labile iron pool and may mimic circadian-dependent changes that have been found in VBM extracellular iron.

Light qualities and dose influence ascorbate pool size in detached oat leaves.

In this work, we studied the mechanism of light influence on AsA pool size in Avena sativa L. under the effects of low intensity light at different wavelengths. Exposure to low intensity light of oat leaf segments incubated in water or in l-galactono-1,4-lactone (GL), resulted in an increase in AsA content compared with the dark control. This increase was due to modulation of l-galactono-1,4-lactone dehydrogenase (GLDH; EC 1.3.2.3) light-dependent activity and was dependent on the size of the endogenous GL pool. Both blue and red light were effective in increasing AsA, and this increase depended on both exposure time and light intensity. Protein biosynthesis, photosynthesis and calcium were involved in controlling the level of light-dependent AsA. We suggest that multiple checkpoints correlated to the presence of light underlie the ascorbate pool size. The presence of a light-activated switch for the maintenance of an adequate AsA level seems to be necessary for the various tasks of scavenging reactive oxygen species, in response to the dark-light cycle which plants experience under natural conditions.

Iron deficiency alters the day-night variation in monoamine levels in mice.

Monoamine metabolism in the central nervous system is altered by dietary iron deficiency, with a stronger effect seen during the active than rest span of the circadian cycle. In this report, we examined changes in intracellular and extracellular monoamine levels, synthetic enzymes, transporter and receptor densities, and responses to amphetamine-induced dopamine (DA) efflux in iron-deficient and iron-sufficient mice. Extracellular striatal DA levels were 15-20% higher in all groups during the active dark phase compared to the inactive light phase, with correspondingly lower dopamine transporter (DAT) and higher tyrosine hydroxylase levels. Iron deficiency decreased DAT density by 20% and 28% in the light and dark phases, respectively, and elevated the DOPAC/DA ratio only in the dark, indicating that iron deficiency does interact with the normal diurnal cues for cyclicity. Enhanced DA efflux after amphetamine stimulation indicates no limitation on monoamine synthesis and release and is consistent with altered synaptic efficacy and perhaps recycling of DA in iron deficiency. These experimental findings provide new evidence that brain iron insufficiency does have a differential effect on the DA system at different biological times of the day and night and may be causally related to the phasic motor symptoms observed in Restless Legs Syndrome.