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Satellite observations of atmospheric CO2 offer the potential to identify regional carbon surface sources and sinks and to investigate carbon cycle processes. The extent to which satellite measurements are useful however, depends on the near surface sensitivity of the chosen sensor. In this paper, the capability of the SCIAMACHY instrument on board ENVISAT, to observe lower tropospheric and surface CO2 variability is examined. To achieve this, atmospheric CO2 retrieved from SCIAMACHY near infrared (NIR) spectral measurements, using the Full Spectral Initiation (FSI) WFM-DOAS algorithm, is compared to in-situ aircraft observations over Siberia and additionally to tower and surface CO2 data over Mongolia, Europe and North America. Preliminary validation of daily averaged SCIAMACHY/FSI CO2 against ground based Fourier Transform Spectrometer (FTS) column measurements made at Park Falls, reveal a negative bias of about −2.0% for collocated measurements within ±1.0° of the site. However, at this spatial threshold SCIAMACHY can only capture the variability of the FTS observations at monthly timescales. To observe day to day variability of the FTS observations, the collocation limits must be increased. Furthermore, comparisons to in-situ CO2 observations demonstrate that SCIAMACHY is capable of observing a seasonal signal that is representative of lower tropospheric variability on (at least) monthly timescales. Out of seventeen time series comparisons, eleven have correlation coefficients of 0.7 or more, and have similar seasonal cycle amplitudes. Additional evidence of the near surface sensitivity of SCIAMACHY, is provided through the significant correlation of FSI derived CO2 with MODIS vegetation indices at over twenty selected locations in the United States. The SCIAMACHY/MODIS comparison reveals that at many of the sites, the amount of CO2 variability is coincident with the amount of vegetation activity. The presented analysis suggests that SCIAMACHY has the potential to detect CO2 variability within the lowermost troposphere arising from the activity of the terrestrial biosphere.

Objectives: To summarize the evidence related to the experiences and challenges of International Medical Graduates (IMGs) in healthcare systems of English-speaking countries., Methods: Following the PRISMA statement, we searched MEDLINE and EMBASE for all peer-reviewed articles using keywords including "international medical graduates," "foreign medical graduates," or "transition," from their inception to December 21st, 2022., Results: In this review, we included 20 articles, comprising 17 descriptive studies and three quasi-experimental studies. These studies highlight the challenges centered around communication skills and languages including the use and meaning of slang, health system differences, cultural distinctions such as varying patient expectations, and the prevalence of biases and preconceived notions about IMGs., Conclusion: This systematic review summarizes the current evidence related to IMGs' transition into healthcare systems in English-speaking countries. Despite the limited quality of available studies, several common issues were identified, including communication skills and language proficiency, cultural understanding, and system-related themes. To improve the experiences of IMGs and the quality of patient care, clinical educators, and residency program leaders may need to provide targeted needs assessments, focused orientations, and year-round programs., Supplementary Information: The online version contains supplementary material available at 10.1007/s40670-024-02126-5., Competing Interests: Conflict of InterestThe authors declare no competing interests., (© The Author(s) under exclusive licence to International Association of Medical Science Educators 2024. Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.)

This report describes the case of an 18-year-old Micronesian pregnant woman at 32 weeks gestation, initially presumed to have eclampsia but later diagnosed with reversible cerebral vasoconstriction syndrome (RCVS). She presented with seizures, altered mental status, nystagmus, lower extremity weakness, and absent reflexes. An extensive workup ruled out infectious and autoimmune causes, but a computed tomography angiogram (CTA) revealed severe cerebral vasoconstriction. Treatment included levetiracetam, intravenous magnesium, and nimodipine. The case highlights the challenge of differentiating RCVS from eclampsia in the postpartum period, emphasizing the importance of considering alternative diagnoses and brain CTA when RCVS is suspected, with calcium channel blockers potentially contributing to favorable neurological outcomes., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2024, Wannaphut et al.)

The advanced stage of the glycation process (one of the post-translational modifications of proteins) leads to the formation of advanced glycation end-products (AGEs) and plays an important role in the pathogenesis of angiopathy in diabetic patients. It has recently become clear that AGEs also influence physiological aging and neurodegenerative diseases such as Alzheimer's disease (AD) and amyotrophic lateral sclerosis (ALS). Recently we have provided direct immunochemical evidence for the existence of six distinct AGE structures within the AGE-modified proteins and peptides that circulate in the serum of diabetic patients on hemodialysis (DM-HD). We showed a direct toxic effect of the synthetic AGE-2 (glyceraldehyde-derived AGEs) on cortical neuronal cells and provided evidence for a toxic effect of AGE-2 present in DM-HD serum. These results indicate that of the various types of AGE structures that can form in vivo, the AGE-2 structure is likely to play an important role in the pathophysiological processes associated with AGE formation. In AD brains, AGE-2 epitope was mainly present in the cytosol of neurons in the hippocampus and para-hippocampal gyrus. Protein cross-linking by AGE structures results in the formation of protease-resistant aggregates. Such protein aggregates may interfere with both axonal transport and intracellular protein traffic in neuron. In this review, we provide an outline of AGEs formation in vivo and propose that the novel structural epitope AGE-2 is an important toxic moiety for neuronal cells in AD.

The Maillard reaction that leads to the formation of advanced glycation end products (AGEs) plays an important role in the pathogenesis of angiopathy in diabetic patients, in aging, and in neurodegenerative processes. We hypothesize that acetaldehyde (AA), one of the main metabolites of alcohol, may be involved in alcohol-induced neurotoxicity in vivo by formation of AA-derived AGEs (AA-AGEs) with brain proteins. Incubation of cortical neurons with AA-AGE produced a dose-dependent increase in neuronal cell-death, and the neurotoxicity of AA-AGE was neutralized by the addition of an anti-AA-AGE-specific antibody, but not by anti-N-ethyllysine (NEL) antibody. The AA-AGE epitope was detected in human brain of alcoholism. We propose that the structural epitope AA-AGE is an important toxic moiety for neuronal cells in alcoholism.

To verify whether noradrenergic inputs to the subfornical organ (SFO) are involved in the control system of arterial pressure, we investigated the effects of blood pressure changes on noradrealine (NA) release in the SFO and its surrounding sites using microdialysis techniques in rats. Hemorrhage (5 or 10 ml/kg) significantly increased the NA concentration in the region of the SFO, but did not cause significant changes in the sites away from the SFO. An elevation in arterial pressure following intravenous administration of the alpha-agonist metaraminol slightly decreased the NA level in the region of the SFO. These results imply that the noradrenergic neural inputs to the SFO area may be involved in the control of cardiovascular function., (Copyright 1998 Academic Press.)

Phasically active neurosecretory neurons in the paraventricular nucleus (PVN) of urethane-anesthetized rats displayed orthodromic excitation, inhibition or no response following electrical stimulation of the anteroventral third ventricle (AV3V) region, and exhibited orthodromic excitation or no response following electrical stimulation of the A1 noradrenergic region of the ventrolateral medulla. Of the 14 neurons that responded to both the stimuli, A1 region stimulation at the subthreshold current significantly enhanced the excitation induced by AV3V region stimulation, and the enhancement was abolished by iontophoretically applied phentolamine, an alpha-adrenoceptor antagonist, but not by timolol, a beta-adrenoceptor antagonist. These results suggest that A1 noradrenergic projections may act to potentiate the excitatory inputs from the AV3V region to vasopressinergic PVN neurons through alpha-adrenoceptor mechanisms.

Extracellular recordings were obtained from 34 phasically active neurosecretory cells in the hypothalamic paraventricular nucleus (PVN) of male rats under urethane anesthesia. Intracarotid injections of hypertonic saline (0.2 M NaCl solution, 0.05 ml) caused an increase in neuronal activity of 27 PVN cells. Pretreatment with saralasin (Sar, 10(-10) M), a specific angiotensin II (ANG II) antagonist, into the median preoptic nucleus (MnPO) diminished the excitatory response to the osmotic stimulation in 13 of 17 cells tested. Pretreatment with Sar in the vicinity of the MnPO or the third ventricle did not cause a marked change. These results suggest that the ANGergic system in the MnPO could contribute to the mechanism of osmotic activation of PVN neurosecretory cells.