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Studies in rodent models of acute and chronic neurodegenerative disorders have uncovered that glutamate-induced excitotoxic cell death is mediated primarily by extrasynaptic N-methyl-d-aspartate receptors (NMDARs). Rodent neurons can also build up in an activity-dependent manner a protective shield against excitotoxicity. This form of acquired neuroprotection is induced by preconditioning with low doses of NMDA or by activation of synaptic NMDARs triggered by bursts of action potentials. Whether NMDARs in human neurons have similar dichotomous actions in cell death and survival is unknown. To investigate this, we established an induced pluripotent stem cell (iPSC)-derived forebrain organoid model for excitotoxic cell death and explored conditions of NMDAR activation that promote neuronal survival when applied prior to a toxic insult. We found that glutamate-induced excitotoxicity in human iPSC-derived neurons is mediated by NMDARs. Treatment of organoids with high concentrations of glutamate or NMDA caused the typical excitotoxicity pathology, comprising structural disintegration, neurite blebbing, shut-off of the transcription factor CRE binding protein (CREB), and cell death. In contrast, bath-applied low doses of NMDA elicited synaptic activity, a robust and sustained increase in CREB phosphorylation as well as function, and upregulation of immediate-early genes, including neuroprotective genes. Moreover, we found that conditions of enhanced synaptic activity increased survival of human iPSC-derived neurons if applied as pre-treatment before toxic NMDA application. These results revealed that both toxic and protective actions of NMDARs are preserved in human neurons. The experimental platform described in this study may prove useful for the validation of neuroprotective gene products and drugs in human neurons.

Type 1 diabetes mellitus (T1DM) is associated with reduced fetal growth in early pregnancy, but a contributing role of the placenta has remained elusive. Thus, we investigated whether T1DM alters placental development in the first trimester. Using a protein array, the level of 60 cell-cycle-related proteins was determined in human first trimester placental tissue (gestational week 5–11) from control (n = 11) and T1DM pregnancies (n = 12). Primary trophoblasts (gestational week 7–12, n = 32) were incubated in the absence (control) or presence of hyperglycemia (25 mM D-glucose) and hyperosmolarity (5.5 mM D-glucose + 19.5 mM D-mannitol). We quantified the number of viable and dead trophoblasts (CASY Counter) and assessed cell cycle distribution (FACS) and trophoblast invasion using a transwell assay. T1DM was associated with a significant (p < 0.05) downregulation of Ki67 (−26%), chk1 (−25%), and p73 (−26%). The number of viable trophoblasts was reduced under hyperglycemia (−23%) and hyperosmolarity (−18%), whereas trophoblast invasion was increased only under hyperglycemia (+6%). Trophoblast cell death and cell cycle distribution remained unaffected. Collectively, our data demonstrate that hyperglycemia decreases trophoblast proliferation as a potential contributing factor to the reduced placental growth in T1DM in vivo.

This research examines the effect of fiber alignment on the performance of an exceptionally tough 3D-printable short carbon fiber reinforced cementitious composite material, the flexural strength of which can exceed 100 N/mm2. The material shows pseudoductility caused by strain-hardening and microcracking. An extrusion-based manufacturing process allows accurate control over the spatial alignment of the fibers’ orientation, since extrusion through a tight nozzle leads to nearly unidirectional alignment of the fibers with respect to the directional movement of the nozzle. Specimens were investigated using mechanical tests (flexural and tensile load), augmented by non-destructive methods such as X-ray 3D computed tomography and acoustic emission analysis to gain insight into the microstructure. Additionally, digital image correlation is used to visualize the microcracking process. X-ray CT confirms that about 70% of fibers show less than 10° deviation from the extrusion direction. Systematic variations of the fiber alignment with respect to the direction of tensile load show that carbon fibers enhance the flexural strength of the test specimens as long as their alignment angle does not deviate by more than 20° from the direction of the acting tensile stress. Acoustic emission analysis is capable of evaluating the spatiotemporal degradation behavior during loading and shows consistent results with the microstructural damage observed in CT scans. The strong connection of fiber alignment and flexural strength ties into a change from ductile to brittle failure caused by degradation on a microstructural level, as seen by complementary results acquired from the aforementioned methods of investigation.

In the adult brain, vascular endothelial growth factor D (VEGFD) is required for structural integrity of dendrites and cognitive abilities. Alterations of dendritic architectures are hallmarks of many neurologic disorders, including stroke-induced damage caused by toxic extrasynaptic NMDA receptor (eNMDAR) signaling. Here we show that stimulation of eNMDARs causes a rapid shutoff of VEGFD expression, leading to a dramatic loss of dendritic structures. Using the mouse middle cerebral artery occlusion (MCAO) stroke model, we have established the therapeutic potential of recombinant mouse VEGFD delivered intraventricularly to preserve dendritic architecture, reduce stroke-induced brain damage, and facilitate functional recovery. An easy-to-use therapeutic intervention for stroke was developed that uses a new class of VEGFD-derived peptide mimetics and postinjury nose-to-brain delivery.

By using a novel fiber-reinforced cement paste in a 3D-printing process, a material with vastly improved flexural and tensile strength can be created. The extrusion-based process leads to a high degree of fiber orientation. A fiber content of 3 vol. % results in static flexural strengths of above 100 MPa. High-strength fiber-reinforced materials have potential to be used in lightweight construction. Due to the susceptibility of lightweight structural members to oscillating dynamic loads, cyclic flexural and tensile tests with up to 10 million cycles are carried out. To characterize the complex (micro-)cracking behavior of the material, the tests are augmented by external deformation sensors (strain gauges, fiber-optic sensors, photogrammetry) and microstructural analysis (X-ray CT, acoustic emission sensors, coda-wave interferometry). The experimental data will serve as the basis for multiscale-modelling approach which uses representative volume elements created from high-resolution CT scans.

Synaptic NMDA receptors activating nuclear calcium-driven adaptogenomics control a potent body-own neuroprotective mechanism, referred to as acquired neuroprotection. Viral vector-mediated gene transfer in conjunction with stereotactic surgery has previously demonstrated the proficiency of several nuclear calcium-regulated genes to protect in vivo against brain damage caused by toxic extrasynaptic NMDA receptor signaling following seizures or stroke. Here we used noninvasive nose-to-brain administration of Activin A and SerpinB2, two secreted nuclear calcium-regulated neuroprotectants, for post-injury treatment of brain damage following middle cerebral artery occlusion (MCAO) in C57BL/6N mice. The observed reduction of the infarct volume was comparable to the protection obtained by intracerebroventricular injection of recombinant Activin A or SerpinB2 or by stereotactic delivery 3 weeks prior to the injury of a recombinant adeno-associated virus containing an expression cassette for the potent neuroprotective transcription factor Npas4. These results establish post-injury, nose-to-brain delivery of Activin A and SerpinB2 as effective and possibly clinically applicable treatments of acute and chronic neurodegenerative conditions.

Background Chronic kidney disease (CKD) is associated with poor renal and cardiovascular outcomes, and early identification largely depends on general practitioners' (GPs') awareness of it. To date, no study has evaluated CKD prevalence in patients with hypertension in primary care. Study Design Cross-sectional evaluation of the Italian GPs' database. Setting & Participants 39,525 patients with hypertension representative of the Italian hypertensive population followed up by GPs in 2005. Factor Estimated glomerular filtration rate (eGFR); eGFR 2 was defined as CKD. Outcomes GPs' awareness of CKD assessed using International Classification of Diseases, Ninth Revision, Clinical Modification diagnostic codes for CKD, and blood pressure (BP) control. Measurements Data concerning serum creatinine levels, BPs, and antihypertensive medications were obtained for each patient from the GPs' database; eGFR was calculated according to the 4-variable Modification of Diet in Renal Disease (MDRD) Study equation. Results CKD prevalence was 23%, but kidney disease was diagnosed by GPs in only 3.9% of patients. BP control was inadequate in patients with CKD and those with eGFR >60 mL/min/1.73 m 2 , with only 44% of patients reaching a BP target 2 whose GPs were aware of CKD were more likely to reach recommended BP target values (OR, 1.35; 95% CI, 1.15-1.59; P Limitations The prevalence of decreased eGFR may be overestimated because of the lack of creatinine calibration. Proteinuria data were not available. Conclusions Awareness of CKD by GPs is critical for achieving the recommended guideline BP targets. However, awareness of CKD by GPs is still far too low, highlighting the need to systematically adopt eGFR for more accurate identification of CKD in high-risk populations.

Chronic kidney disease (CKD) is associated with elevated cardiovascular morbidity and mortality. Cardiovascular disease (CVD) is highly prevalent in CKD and mortality due to CVD is 5- to 200-fold higher in dialysis patients than in the general population.

Calcium-binding proteins (CaBPs) such as parvalbumin are part of the cellular calcium buffering system that determines intracellular calcium diffusion and influences the spatiotemporal dynamics of calcium signals. In neurons, CaBPs are primarily localized to the cytosol and function, for example, in nerve terminals in short-term synaptic plasticity. However, CaBPs are also expressed in the cell nucleus, suggesting that they modulate nuclear calcium signals, which are key regulators of neuronal gene expression. Here we show that the calcium buffering capacity of the cell nucleus in mouse hippocampal neurons regulates neuronal architecture by modulating the expression levels of VEGFD and the complement factor C1q-c, two nuclear calcium-regulated genes that control dendrite geometry and spine density, respectively. Increasing the levels of nuclear calcium buffers by means of expression of a nuclearly targeted form of parvalbumin fused to mCherry (PV.NLS-mC) led to a reduction in VEGFD expression and, as a result, to a decrease in total dendritic length and complexity. In contrast, mRNA levels of the synapse pruning factor C1q-c were increased in neurons expressing PV.NLS-mC, causing a reduction in the density and size of dendritic spines. Our results establish a close link between nuclear calcium buffering capacity and the transcription of genes that determine neuronal structure. They suggest that the development of cognitive deficits observed in neurological conditions associated with CaBP deregulation may reflect the loss of necessary structural features of dendrites and spines.

The function of MeCP2, a methylated DNA-interacting protein that may act as a global chromatin modifier, is controlled by its phosphorylation on serine 421. Here we show that in hippocampal neurons, nuclear calcium signaling controls synaptic activity-induced phosphorylation of MeCP2 on serine 421. Pharmacological inhibition of calcium/calmodulin-dependent protein (CaM)kinases blocked activity-induced MeCP2 serine 421 phosphorylation. CaM kinase II (CaMKII) but not CaMKIV, the major nuclear CaM kinase in hippocampal neurons, appeared to mediate this phosphorylation event. Biochemical subcellular fractionations and immunolocalization studies revealed that several isoforms of CaMKII (i.e. CaMKIIα, -β, -γ, and -δ) are expressed in the cytosol but are also detectable in the cell nucleus of hippocampal neurons, suggesting that nuclear CaMKII catalyzes MeCP2 serine 421 phosphorylation. Thus, in addition to the classical nuclear calcium-CaMKIV-CREB/CBP (cAMP-response element-binding protein/CREB-binding protein) pathway that regulates transcription of specific target genes, nuclear calcium may also modulate genome-wide the chromatin state in response to synaptic activity via nuclear CaMKII-MeCP2 signaling.

The accumulation of somatic mutants in splenic B lymphocytes early after primary immunization with the hapten (4-hydroxy-3-nitro-phenyl)acetyl (NP) coupled to chicken gamma globulin (CG) was determined. Rearranged V186.2 heavy chain genes were amplified by the polymerase chain reaction from genomic DNA and subjected to nucleotide sequence analysis. Somatic antibody mutants become detectable on day 6 after immunization, and most of the somatic mutations accumulating in the memory compartment are introduced until day 14. At this time strong selection for mutants expressing high binding affinity for NP is apparent. Extrapolation from the mutation frequency increases between day 6 and day 14 to the previously determined mutation frequency at week 6 (Weiss. U. and Rajewsky, K., J. Exp. Med. 1990, 172: 1681) leads to the prediction that the process of mutant generation ceases to operate around day 22 after primary immunization.

Diabetic nephropathy is one of the main causes of end-stage renal disease (ESRD) and is associated with elevated cardiovascular morbidity and mortality. Current renoprotective treatment for diabetic nephropathy includes strict glycemic and optimal blood pressure control, proteinuria/albuminuria reduction and the use of renin-angiotensin-aldosterone system (RAAS) blocking agents. However, the renoprotection provided by these treatments is only partial, and many patients still have progressive disease, thus suggesting that a more effective approach is urgently needed. This review examines emerging strategies for the treatment of diabetic nephropathy, including aggressive RAAS blockade, statins, pentoxifylline, glitazones, ruboxistaurin, as well as sulodexide. Pilot studies that used surrogate end points, mainly albuminuria, will be discussed. New insights suggest that treating microalbuminuric diabetic patients with statins, pentoxifylline, glitazones and sulodexide could be a new approach for reducing the incidence of clinical proteinuria. In diabetic patients with overt nephropathy, the administration of statins, pentoxifylline, sulodexide or aggressive RAAS inhibition, including RAAS dual blockade (i.e., angiotensin-converting enzyme [ACE] inhibitors plus angiotensin receptor blockers or aldosterone antagonists plus ACE inhibitors or angiotensin receptor blockers), seems to be a promising way to preserve renal function and to prevent progression to ESRD. Results of ongoing, long-term trials on major renal and cardiovascular clinical outcomes, as well as on mortality are needed to establish whether the current standard of care of diabetic nephropathy might be improved with these new strategies.

Background. Chronic kidney disease (CKD) is associated with poor renal and cardiovascular (CV) outcome, and early identification largely depends on the general practitioners' (GPs) awareness of it. Only a few studies have evaluated the prevalence of CKD in type 2 diabetes in primary care, and no studies are available on hypertensive diabetics. Thus, the aim of this study was to assess the prevalence of CKD and its association with CV morbidity in such a population. Methods. On the basis of an Italian national project involving GPs and nephrologists, we retrieved demographic, laboratory and clinical data regarding 7582 hypertensive type 2 diabetics (3564 men; age 25-89 years) who were selected using the diagnostic code Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) for diabetes and hypertension. Blood pressure (BP) values, serum creatinine, ECG-diagnosed left ventricular hypertrophy (LVH) and the occurrence of previous major CV events were obtained for each patient from the GPs' Health Search Database. Estimated glomerular filtration rate (GFR) was calculated according to the four-variable MDRD equation. CKD was defined as an estimated GFR < 60 mL/min/ 1.73 m 2 . Results. CKD prevalence was 26%, although renal disease was diagnosed by GPs in only 5.4% of cases. The prevalence of both LVH and major CV events was 8%. Adequate BP control was only achieved in 10.4% of patients. Patients whose GFR was

Background: Changes in lipid profile have long been associated with malignancies as lipids play a key role in maintenance of cell integrity. This study evaluated the alterations in extended lipid profile in untreated patients of oral submucous fibrosis (OSMF) and studied the correlation between lipid levels with tobacco consumption. Materials and methods: In this hospital-based study, 65 clinically diagnosed and histopathologically proven patients of OSMF and 42 age and sex matched controls were studied. In these samples serum lipids including: (i) Total cholesterol, (ii) LDL cholesterol (LDLC), (iii) HDL cholesterol (HDLC) (iv) VLDL cholesterol (VLDLC) (v) triglycerides (vi) Apo-A1 (viii) Apo-B and (viii) LPa were analyzed. Results: A significant decrease in plasma total cholesterol, HDLC and Apo-A1 was observed in patients with OSMF as compared to the controls. Thus an inverse relationship between plasma lipid levels and patients was found in OSMF. Conclusion: The lower levels of plasma cholesterol and other lipid constituents in patients might be due to their increased utilization. The findings strongly warrant an in-depth study of alterations in plasma lipid profile in patients with oral precancerous conditions.

Chromogranin B (CgB, secretogranin I) is a secretory granule matrix protein expressed in a wide variety of endocrine cells and neurons. Here we generated transgenic mice expressing CgB under the control of the human cytomegalovirus promoter. Northern and immunoblot analyses, in situ hybridization and immunocytochemistry revealed that the exocrine pancreas was the tissue with the highest level of ectopic CgB expression. Upon subcellular fractionation of the exocrine pancreas, the distribution of CgB in the various fractions was indistinguishable from that of amylase, an endogenous constituent of zymogen granules. Immunogold electron microscopy of pancreatic acinar cells showed co-localization of CgB with zymogens in Golgi cisternae, condensing vacuoles/immature granules and mature zymogen granules; the ratio of immunoreactivity of CgB to zymogens being highest in condensing vacuoles/immature granules. CgB isolated from zymogen granules of the pancreas of the transgenic mice aggregated in a mildly acidic (pH 5.5) milieu in vitro, suggesting that low pH-induced aggregation contributed to the observed concentration of CgB in condensing vacuoles. Our results show that a neuroendocrine-regulated secretory protein can be sorted to exocrine secretory granules in vivo, and imply that a key feature of CgB sorting in the trans-Golgi network of neuroendocrine cells, i.e. its aggregation-mediated concentration in the course of immature secretory granule formation, also occurs in exocrine cells although secretory protein sorting in these cells is thought to occur largely in the course of secretory granule maturation.

The generation and selection of somatic antibody mutants are key elements of acquired immunity, essential for the affinity maturation of antibody responses dependent on T cells. The mutants are generated through a mechanism that introduces point mutations at high rate into rearranged variable (V) region genes in the course of cell proliferation. Their appearance coincides with the generation of germinal centres, which are characterized by oligoclonal B-cell proliferation and have been suggested to be the microenvironment in which antibody mutants are generated. We report here direct evidence for this hypothesis. Rearranged V-region genes were amplified from the genomic DNA of cells picked from individual germinal centres. The sequence analysis of these genes revealed that most represent cells of distinct B-cell clones which expanded locally, generating somatic antibody mutants at high rate. By contrast, antigen-induced proliferation of B cells at another site, periarteriolar lymphocyte sheath-associated foci, was not associated with somatic hypermutation.

THE specificity of vesicular transport in a cell is determined by the formation of vesicles with specific contents from a donor compartment and their selective fusion with the appropriate acceptor compartment. Several of the latter fusion steps have been investigated in detail using cell-free systems1–9, and work with these systems as well as genetic evidence has revealed a role for GTP-binding proteins in membrane fusion processes7–15. We have reconstituted the formation of constitutive secretory vesicles and immature secretory granules from the trans Golgi network in a cell-free system16. We show here that the budding of both types of post-Golgi vesicles is inhibited by non-hydrolysable analogues of GTP, which suggests a more widespread role for GTP-binding proteins in membrane traffic than previously assumed.

Repair of heteroduplex DNA, generated between two interacting DNA molecules during homologous recombination, has been implicated as a contributing factor in the process of gene conversion. To assess patterns of heteroduplex repair in mammalian cells, we constructed 13 different heteroduplexes from simian virus 40 wild-type and deletion mutant DNAs. Each heteroduplex contained one or multiple single-stranded loops in the intron of the gene for large tumor antigen, which is not essential during lytic infection. After transfection into cultured monkey cells, cellular repair was evaluated by restriction analysis of the amplified viral progeny from 1123 individual plaques, each representing the clonal expansion of a single repair event. Single-stranded loops were corrected prior to replication with an overall efficiency of 90%. At the position of a loop, one of the two heteroduplex strands served as a template for accurate repair 98% of the time. Repair of single-stranded loops was biased nearly 2 to 1 in favor of the strand without the loop. The efficiency, accuracy, and strand bias of repair were unaffected by loop size within the tested range, which was 25-247 nucleotides. The excision tract associated with repair of single-stranded loops rarely exceeds 200-400 nucleotides in length.

Haltung resultiert aus dem Wechselspiel sehr vieler Faktoren und ist zudem Ausdruck des Verhaltens eines Individuums gegenuber einer bestimmten Situation. Entsprechen die individuellen Voraussetzungen, vor allem die Halteleistungsfahigkeit und die Halteleistungsbereitschaft, nicht den Belastungsanforderungen der Situation, so kommt es zu Abweichungen von der "normalen" aufrechten Haltung. Es entwickeln sich Haltungsschwachen, welche leicht in irreversible Haltungsschaden ubergehen konnen.

Angular distributions of the elastic scattering of 28 Si on 29 Si and 30 Si have been measured for incident beam energies at E = 65 and 70 MeV with a time-of-flight spectrometer for heavy ions. At 70 MeV the neutron transfer 30 Si( 28 Si, 29 Si) 29 Si was observed in addition to the elastic channel. The pronounced oscillations in the elastic scattering distributions are interpreted as being due to an elastic transfer of neutrons between the colliding nuclei during the scattering process. This assumption is in accordance with some general features of the data and allows for the extraction of spectroscopic factors of the transferred neutrons.

The elastic scattering of 12 C on 13 C has been measured between c.m. energies of 4.8 and 9.5 MeV in steps of 48 keV at θ c.m. = 90°. The absence of resonance-like structures comparable to those observed in 12 C- 12 C scattering is discussed with respect to the influence of the elastic neutron transfer. The presence of this transfer even below the barrier is demonstrated by the measurement of an angular distribution of the 12 C- 13 C scattering at E c.m. = 5.76 MeV.

We have shown previously that heteroduplexes containing single-stranded loops are repaired efficiently in monkey cells, but not always correctly: 2% of the repair products acquired mutations within a 350 base-pair target (Weiss, U. and Wilson, J.H., Proc. Natl. Acad. Sci. USA 87:1123-1126, 1987). The structures of the mutant genomes, which are described here, are consistent with an error-prone repair system. The spectrum of mutations includes about 25% point mutations and 75% rearrangements, which consist of deletions, duplications, and substitutions. The mutations are clustered in the vicinity of single-stranded loops in the original heteroduplex. The high frequency of mutation, their clustering, and the positions of rearrangement endpoints suggest that the mutations were generated during repair of the heteroduplexes.

The2H(d, n)- and2H(d, p)-reactions are studied for deuteron energies below 200 keV. It is shown that theR-matrix approach of Konopinski and Teller, which is very sensitive to the channel radius used, can be approximated in a way that the dependence on the channel radius does not appear explicitly. This approach appears to be formally equivalent to a kind of “direct approach” of Boersma. This equivalence answers the question why a direct approach to these reactions works at all at low energies. Each reaction is described by three parameters which are determined in a fit to the up to now available data.

Die kleinsten lebenden Bausteine unseres Korpers sind die Zellen; ihre Zahl betragt beim erwachsenen Menschen je nach Korpergrosse zwischen 10 und 100 Billionen (1 Bio = 1 Million Millionen). Neben freien Zellen, welche unabhangig voneinander im Korper leben (freie Bindegewebszellen, Blutzellen und Geschlechtszellen), bilden grossere Verbande gleichartiger Zellen, erganzt durch Zwischenzellsubstanz, die verschiedenen Gewebe: die Deckgewebe, die Binde- und Stutzgewebe, das Muskel- und das Nervengewebe. Zellen und Gewebe sind am Auf bau der Organe beteiligt, den eigentlichen Werkzeugen des Korpers. Die einzelnen Organe, zum Beispiel Nase, Rachen, Kehlkopf, Luftrohre, Lungen mit den dazugehorenden Nerven und Blutgefassen bilden zusammen Organsysteme, welche in ihrer Gesamtheit eine bestimmte Aufgabe, im genannten Beispiel die Atemfunktion, zu erfullen haben. Die verschiedenen Systeme wieder stehen untereinander in enger Verbindung.

Das Skelett ist der passive Anteil des Bewegungsapparates, aufgebaut aus einer Folge zahlreicher Knochen, die in typischer Weise miteinander in Verbindung stehen. Die Haltung der einzelnen Teile zueinander und die Bewegungen gegeneinander werden durch die Muskulatur, den aktiven Teil des Bewegungsapparates, gewahrleistet.

Aus biologischer Sicht liegt der Sinn eines Trainings darin, durch geeignete korperliche Belastungen im Organismus Anpassungsprozesse auszulosen. Die Wirkung dieses Vorganges ist eine Verbesserung der korperlichen Leistungsfahigkeit.