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Noradrenaline (NA) levels are altered during the first hours and several days after cortical injury. NA modulates motor functional recovery. The present study investigated whether iron-induced cortical injury modulated noradrenergic synthesis and dopamine beta-hydroxylase (DBH) activity in response to oxidative stress in the brain cortex, pons and cerebellum of the rat. Seventy-eight rats were divided into two groups: (a) the sham group, which received an intracortical injection of a vehicle solution; and (b) the injured group, which received an intracortical injection of ferrous chloride. Motor deficits were evaluated for 20 days post-injury. On the 3rd and 20th days, the rats were euthanized to measure oxidative stress indicators (reactive oxygen species (ROS), reduced glutathione (GSH) and oxidized glutathione (GSSG)) and catecholamines (NA, dopamine (DA)), plus DBH mRNA and protein levels. Our results showed that iron-induced brain cortex injury increased noradrenergic synthesis and DBH activity in the brain cortex, pons and cerebellum at 3 days post-injury, predominantly on the ipsilateral side to the injury, in response to oxidative stress. A compensatory increase in contralateral noradrenergic activity was observed, but without changes in the DBH mRNA and protein levels in the cerebellum and pons. In conclusion, iron-induced cortical injury increased the noradrenergic response in the brain cortex, pons and cerebellum, particularly on the ipsilateral side, accompanied by a compensatory response on the contralateral side. The oxidative stress was countered by antioxidant activity, which favored functional recovery following motor deficits.
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OBJECTIVES: The illicit cigarette trade endangers public health because it increases access to cheaper tobacco products, hence fueling the tobacco epidemic and undermining tobacco control policies. The objective of this study was to evaluate the execution of an illicit cigarette eradication program under the jurisdiction of the local government in Indonesia. We sought to provide insights into the effectiveness of current policies and their impact on the illicit cigarette trade in line with the World Health Organization Framework Convention on Tobacco Control (WHO FCTC) protocol to eliminate illicit trade in tobacco products. METHODS: We conducted semistructured interviews with key policy-makers and semistructured FGDs with consumers and small- to medium-scale cigarette manufacturers at the district level. We indentified Pasuruan and Kudus as the districts or cities with the highest proportion of DBH CHT, and Jepara and Malang as a district with a highest illicit cigarette incident. We used reflective thematic analysis to identify the important opportunities and challenges facing illicit cigarette eradication programs in the three districts. RESULTS: We identified four opportunities and four challenges related to illicit cigarette eradication program implementation under the local government. The opportunities for illicit cigarette eradication lie in strong central government regulatory and multisectoral authority support, consumer awareness, and local governments' commitment to tobacco supply chain control. The key challenges facing illicit cigarette eradication include ineffective public dissemination programs, rapidly changing regulatory designs, consumers' preferences for illicit products, and a lack of industrial involvement in tobacco supply chain control programs. CONCLUSION: In addition to significant budget allocation and increasing consumer awareness, local programs to eradicate illicit cigarette production require considerable evaluation to rethink the program's design and external stakeholders' engagement within the local government's scope.
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Comercio , Impuestos , Productos de Tabaco , Humanos , Productos de Tabaco/economía , Productos de Tabaco/legislación & jurisprudencia , Impuestos/economía , Indonesia/epidemiología , Comercio/economía , Investigación Cualitativa , Industria del Tabaco/economía , Industria del Tabaco/legislación & jurisprudencia , Prevención del Hábito de Fumar/economía , Prevención del Hábito de Fumar/métodos , Crimen/prevención & control , Crimen/economía , Fumar/epidemiología , Fumar/economíaRESUMEN
Sleep disturbances are common among children with neurodevelopmental disorders. Here, we report a syndrome characterized by prenatal microcephaly, intellectual disability and severe disruption of sleep-wake cycles in a consanguineous family. Exome sequencing revealed homozygous variants (c.5224G>A and c.6506G>T) leading to the missense mutations E1742K and G2169V in integrator complex subunit 1 (INTS1), the core subunit of the Integrator complex. Conservation and structural analyses suggest that G2169V has a minor impact on the structure and function of the complex, while E1742K significantly alters a negatively charged conserved patch on the surface of the protein. The severe sleep-wake cycles disruption in human carriers highlights a new aspect of Integrator complex impairment. To further study INTS1 pathogenicity, we generated Ints1-deficient zebrafish lines. Mutant zebrafish larvae displayed abnormal circadian rhythms of locomotor activity and sleep, as is the case with the affected humans. Furthermore, Ints1-deficent larvae exhibited elevated levels of dopamine ß-hydroxylase (dbh) mRNA in the locus coeruleus, a wakefulness-inducing brainstem center. Altogether, these findings suggest a significant, likely indirect, effect of INTS1 and the Integrator complex on maintaining circadian rhythms of locomotor activity and sleep homeostasis across vertebrates.
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Ritmo Circadiano , Sueño , Pez Cebra , Animales , Pez Cebra/genética , Humanos , Femenino , Masculino , Ritmo Circadiano/genética , Sueño/genética , Sueño/fisiología , Vigilia/fisiología , Vigilia/genética , Larva/genética , Linaje , Secuencia de Aminoácidos , Proteínas de Pez Cebra/genética , Proteínas de Pez Cebra/metabolismo , NiñoRESUMEN
The DinB homolog polymerase (Dbh) is a member of the Y-family of translesion DNA polymerases that can synthesize using a damaged DNA template. Since Dbh comes from the thermophilic archaeon Sulfolobus acidocaldarius, it is capable of functioning over a wide range of temperatures. Existing X-ray structures were determined at temperatures where the protein is least active. Here we use NMR and circular dichroism to understand how the structure and dynamics of Dbh are affected by temperature (2°C-65°C) and metal ion binding in solution. We measured hydrogen exchange protection factors, temperature coefficients, and chemical shift perturbations with and without magnesium and manganese. We report on regions of the protein that become more dynamic as the temperature is increased toward the functional temperature. Hydrogen exchange protection factors and temperature coefficients reveal that both the thumb and finger domains are very dynamic relative to the palm and little-finger (LF) domains. These trends remain true at high temperature with dynamics increasing as temperatures increase from 35°C to 50°C. Notably, NMR spectra show that the Dbh tertiary structure cold denatures beginning at 25°C and increases in denaturation as the temperature is lowered to 5°C with little change observed by CD. Above 35°C, chemical shift perturbation analysis in the presence and absence of magnesium and manganese reveals three ion binding sites, without DNA bound. In contrast, these bound metals are not apparent in any Dbh crystal structures of the protein without DNA. Two ion binding sites are confirmed to be near the active site, as reported in other Y-family polymerases, and we report a novel ion binding site in the LF domain. Thus, the solution-state structure of the Dbh polymerase is distinct from that of the solid-state structures and shows an unusually high cold denaturation temperature.
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Background: Genetic variants causing diseases with hypertension as a secondary feature have previously been identified. Studies focussing on primary hypertension have utilised common and latterly rare genetic variants in attempts to elucidate the genetic contribution to the risk of primary hypertension. Summary: Using genome-wide association studies (GWASs), associations of hypertension with hundreds of common genetic variants have been reported, implicating thousands of genes. Individual variants have small effect sizes and cumulatively account for around 6% of genetic risk. The common variant signal is enriched for relevant tissues and physiological processes, while some variants are associated with traits expected to have secondary impacts on hypertension risk, such as fruit intake, BMI, or time watching television. Studies using rare variants obtained from exome sequence data have implicated a small number of genes for which impaired function has moderate effects on blood pressure and/or hypertension risk. Notably, genetic variants which impair elements of guanylate cyclase activation, stimulated by either natriuretic hormones or nitric oxide, increase hypertension risk. Conversely, variants impairing dopamine beta-hydroxylase or renin production are associated with lower blood pressure. Variants for which a definite effect can be designated remain cumulatively extremely rare and again make only a small contribution to overall genetic risk. Although these results are of interest, it is not clear that they provide radical new insights or identify drug targets which were not previously known. Nor does it seem that genetic testing could be useful in terms of quantifying disease risk or guiding treatment. Key Messages: Research has increased our knowledge about the relationship between naturally occurring genetic variation and risk of hypertension. Although some results serve to confirm our understanding of underlying physiology, their value in terms of potentially leading to practical advances in the management of hypertension appears questionable.
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AIMS: Alcoholic liver disease (ALD) can develop into cirrhosis and hepatocellular carcinoma but no specific drugs are available. Fenofibrate is therapeutically effective in ALD, however, the exact mechanism remains unknown. We explored the hub genes of ALD and the role of fenofibrate in ALD. MAIN METHODS: The hub genes of ALD were screened by bioinformatics method, and their functional enrichment, signalling pathways, target genes and their correlation with immune microenvironment and pathogenic genes were analysed. We also analysed the binding affinity of fenofibrate to proteins of hub genes using molecular docking techniques, and the effects on hub gene expression, lipid deposition, oxidative stress and inflammation in the liver of National Institute on Alcohol Abuse and Alcoholism (NIAAA) model mice. The regulatory effects of fenofibrate on MOXD1 and PDZK1P1 were investigated after gene silencing of peroxisome proliferator-activated receptor-α (Ppar-α). KEY FINDINGS: Hub genes identified, including monooxygenase DBH-like 1 (MOXD1), PDZK1-interacting protein 1 (PDZK1IP1) and solute carrier 51 ß (SLC51B), are highly predictive for ALD. Hepatic MOXD1 and PDZK1IP1 expression was elevated in patients with ALD and NIAAA model mice, with no significant difference in SLC51B expression between the groups. Fenofibrate binds tightly to MOXD1 and PDZK1IP1, inhibits their hepatic expression independently of PPAR-α signalling, and ameliorates lipid deposition, oxidative stress and inflammatory responses in NIAAA model mice. SIGNIFICANCE: MOXD1 and PDZK1IP1 are key genes in ALD progression; fenofibrate improves liver damage in NIAAA model mice by downregulating their expression. Our findings provide insight for improving diagnostic and therapeutic strategies for ALD.
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Hígado Graso Alcohólico , Fenofibrato , Hipercolesterolemia , Hepatopatías Alcohólicas , Ratones , Humanos , Animales , Fenofibrato/farmacología , Fenofibrato/uso terapéutico , Hígado Graso Alcohólico/tratamiento farmacológico , Simulación del Acoplamiento Molecular , Hígado/metabolismo , Inflamación/metabolismo , PPAR alfa/genética , PPAR alfa/metabolismo , Hipercolesterolemia/metabolismo , Hepatopatías Alcohólicas/patología , Lípidos/farmacología , Proteínas de la Membrana/metabolismoRESUMEN
Background: Contextual fear learning is heavily dependent on the hippocampus. Despite evidence that catecholamines contribute to contextual encoding and memory retrieval, the precise temporal dynamics of their release in the hippocampus during behavior is unknown. In addition, new animal models are required to probe the effects of altered catecholamine synthesis on release dynamics and contextual learning. Methods: We generated 2 new mouse models of altered locus coeruleus-norepinephrine (NE) synthesis and utilized them together with GRABNE and GRABDA sensors and in vivo fiber photometry to investigate NE and dopamine (DA) release dynamics in the dorsal hippocampal CA1 during contextual fear conditioning. Results: Aversive foot shock increased both NE and DA release in the dorsal CA1, while freezing behavior associated with recall of fear memory was accompanied by decreased release. Moreover, we found that freezing at the recent time point was sensitive to both partial and complete loss of locus coeruleus-NE synthesis throughout prenatal and postnatal development, similar to previous observations of mice with global loss of NE synthesis beginning postnatally. In contrast, freezing at the remote time point was compromised only by complete loss of locus coeruleus-NE synthesis beginning prenatally. Conclusions: Overall, these findings provide novel insights into the role of NE in contextual fear and the precise temporal dynamics of both NE and DA during freezing behavior and highlight complex relationships between genotype, sex, and NE signaling.
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Introduction: A previous study of 200,000 exome-sequenced UK Biobank participants to test for association of rare coding variants with hypertension implicated two genes at exome-wide significance, DNMT3A and FES. A total of 42 genes had an uncorrected p value <0.001. These results were followed up in a larger sample of 470,000 exome-sequenced participants. Methods: Weighted burden analysis of rare coding variants in a new sample of 97,050 cases and 172,263 controls was carried out for these 42 genes. Those showing evidence for association were then analysed in the combined sample of 167,127 cases and 302,691 controls. Results: The association of DNMT3A and FES with hypertension was replicated in the new sample and they and the previously implicated gene NPR1, which codes for a membrane-bound guanylate cyclase, were all exome-wide significant in the combined sample. Also exome-wide significant as risk genes for hypertension were GUCY1A1, ASXL1, and SMAD6, while GUCY1B1 had a nominal p value of <0.0001. GUCY1A1 and GUCY1B1 code for subunits of a soluble guanylate cyclase. For two genes, DBH, which codes for dopamine beta hydroxylase, and INPPL1, rare coding variants predicted to impair gene function were protective against hypertension, again with exome-wide significance. Conclusion: The findings offer new insights into biological risk factors for hypertension which could be the subject of further investigation. In particular, genetic variants predicted to impair the function of either membrane-bound guanylate cyclase, activated by natriuretic peptides, or soluble guanylate cyclase, activated by nitric oxide, increase risk of hypertension. Conversely, variants impairing the function of dopamine beta hydroxylase, responsible for the synthesis of norepinephrine, reduce hypertension risk.
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This contribution focuses on a comparison of modern geomatics technologies for the derivation of growth parameters in forest management. The present text summarizes the results of our measurements over the last five years. As a case project, a mountain spruce forest with planned forest logging was selected. In this locality, terrestrial laser scanning (TLS) and terrestrial and drone close-range photogrammetry were experimentally used, as was the use of PLS mobile technology (personal laser scanning) and ALS (aerial laser scanning). Results from the data joining, usability, and economics of all technologies for forest management and ecology were discussed. ALS is expensive for small areas and the results were not suitable for a detailed parameter derivation. The RPAS (remotely piloted aircraft systems, known as "drones") method of data acquisition combines the benefits of close-range and aerial photogrammetry. If the approximate height and number of the trees are known, one can approximately calculate the extracted cubage of wood mass before forest logging. The use of conventional terrestrial close-range photogrammetry and TLS proved to be inappropriate and practically unusable in our case, and also in standard forestry practice after consultation with forestry workers. On the other hand, the use of PLS is very simple and allows you to quickly define ordered parameters and further calculate, for example, the cubic volume of wood stockpiles. The results from our research into forestry show that drones can be used to estimate quantities (wood cubature) and inspect the health status of spruce forests, However, PLS seems, nowadays, to be the best solution in forest management for deriving forest parameters. Our results are mainly oriented to practice and in no way diminish the general research in this area.
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Trace elements within the brain are important for proper neurological function, but their imbalance has been rarely investigated in glioblastoma. This study enrolled a total of 14 patients with glioblastoma, and the tumor and peritumoral brain tissues were collected while undergoing surgery. The concentrations of Mg, Ca, Cr, Mn, Fe, Co, Cu, Zn, Se, As, Cd, Tl and Pb were determined using a well-evaluated ICP-MS method. The Cu- and Cd-binding proteomes were further analyzed using the anatomic transcriptional atlas from Ivy GAP. Histological evaluation was based on rubeanic acid staining and immunohistochemistry, respectively. The 13 trace element concentrations were obtained, and the highest were Ca, Mn, Fe, Zn and Cu, ranging from a few to dozens of ug/g. Correlation analysis suggested the existence of two intra-correlated clusters: essential metals (Cu-Ca-Zn-Mg) and heavy metals (Pb-As-Cd-Tl-Co-Cr-Mn). Compared to the tumor samples, significantly higher levels of Cu and Cd were observed in the peritumoral region. Further analysis of the Cu- and Cd-binding proteins from the anatomic view suggested that DBH and NOS1 were obviously increased in the leading edge than the central tumor region. Consistent with the above findings, histological evaluation of Cu and DBH further confirmed more copper and DBH expressions in the peritumoral area compared to the tumor core. Trace elements differ in tumor and peritumoral brain zone in glioblastoma, which may associate with tumor angiogenesis.
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Glioblastoma , Metales Pesados , Oligoelementos , Humanos , Oligoelementos/análisis , Cobre , Cadmio , Plomo , EncéfaloRESUMEN
The author identified the genes and proteins of human enzymes involved in the biosynthesis of catecholamines (dopamine, norepinephrine, epinephrine) and tetrahydrobiopterin (BH4): tyrosine hydroxylase (TH), aromatic L-amino acid decarboxylase (AADC), dopamine ß-hydroxylase (DBH), phenylethanolamine N-methyltransferase (PNMT), and GTP cyclohydrolase I (GCH1). In Parkinson's disease (PD), the activities and levels of mRNA and protein of all catecholamine-synthesizing enzymes are decreased, especially in dopamine neurons in the substantia nigra. Hereditary GCH1 deficiency results in reductions in the levels of BH4 and the activities of TH, causing decreases in dopamine levels. Severe deficiencies in GCH1 or TH cause severe decreases in dopamine levels leading to severe neurological symptoms, whereas mild decreases in TH activity in mild GCH1 deficiency or in mild TH deficiency result in only modest reductions in dopamine levels and symptoms of DOPA-responsive dystonia (DRD, Segawa disease) or juvenile Parkinsonism. DRD is a treatable disease and small doses of L-DOPA can halt progression. The death of dopamine neurons in PD in the substantia nigra may be related to (i) inflammatory effect of extra neuronal neuromelanin, (ii) inflammatory cytokines which are produced by activated microglia, (iii) decreased levels of BDNF, and/or (iv) increased levels of apoptosis-related factors. This review also discusses progress in gene therapies for the treatment of PD, and of GCH1, TH and AADC deficiencies, by transfection of TH, AADC, and GCH1 via adeno-associated virus (AAV) vectors.
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Dendrometer bands have been proposed as an accurate method for measuring tree growth. However, the constrained observation window and the material used in them hamper long-term tree growth monitoring. This study devised a dendrometer band made from stainless steel and primarily extended the extension length of the band spring to yield ample space to monitor diameter increments long-term. A total of more than 500 individual trees, including both coniferous and broadleaf trees, were examined. We compared the dendrometer band's long-term performance with diameter tape for 5- and 10-year measurements. The results showed that the measurements of the two methods were highly correlated (R > 0.89) in both measuring periods. Differences between the two measurements for individual trees were typically less than 5 mm, and the mean differences at a stand level were less than 2 mm. These consistent observations suggested that the dendrometer band measurements were reliable for long-term measurement. Using the dendrometer bands, we further demonstrated the annual tree growths of diameter at breast height (DBH) and basal area (BA) for ten years of measurements. The size-dependent relationships between DBH/BA growth and initial DBH were also presented. Owing to their simple installation, low cost, and reliable measurement, these dendrometer bands would be helpful in forestry and forest ecology research.
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Renal cell carcinoma (RCC) is one of the leading causes of death in men. Messenger ribonucleic acid (mRNA) vaccines may be an attractive means to achieve satisfactory results. Cancer immunotherapy is a promising cancer treatment strategy. However, immunotherapy is not widely used in renal cell carcinoma, as only a few patients show a positive response. The present study aimed to identify potential antigens associated with renal cell carcinoma to develop an anti-renal cell carcinoma mRNA vaccine. Moreover, the immune subtypes of renal cell carcinoma cells were determined. The Cancer Genome Atlas (TCGA) analysis revealed gene expression profiles and clinical information. Antigen-presenting cells infiltrated the immune system using Tumor Immune Estimation Resource (TIMER) tool (http://timer.cistrome.org/). GDSC (Genomics of Drug Sensitivity in Cancer) database were used to estimate drug sensitivity. The 13 immune-related genes discovery could be targets for immunotherapy in renal cell carcinoma patients, as they were associated with a better prognosis and a higher level of antigen-presenting cells. These immune subtypes have significant relationships with immunological checkpoints, immunogenic cell death regulators, and RCC prognostic variables. Furthermore, DBH-AS1 was identified as a potential antigen for developing an mRNA vaccine. The CCK8 assay demonstrated that the proliferative capacity of 786-O and Caki-1 cells overexpressing DBH-AS1 was higher than in the control group. In addition, transwell assay revealed that 786-O and Caki-1 cells overexpressing DBH-AS1 showed higher invasion capacity compared with control. This study provides a theoretical basis for the development of mRNA vaccines. Our findings suggest that DBH-AS1 could be potential antigens for developing RCC mRNA vaccines.
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Carcinoma de Células Renales , Neoplasias Renales , Humanos , Masculino , Carcinoma de Células Renales/patología , Antígenos de Neoplasias/genética , Neoplasias Renales/patología , Inmunoterapia , Factores Inmunológicos , ARN Mensajero/genética , ARN Mensajero/metabolismo , Vacunas de ARNmRESUMEN
Fighting external pathogens relies on the tight regulation of the gene expression of the immune system. Ferroptosis, which is a distinct form of programmed cell death driven by iron, is involved in the enhancement of follicular helper T cell function during infection. The regulation of RNA is a key step in final gene expression. The present study aimed to identify the expression level of antisense lncRNAs (A2M-AS1, DBH-AS1, FLVCR1-DT, and NCBP2AS2-1) and FLVCR1 in COVID-19 patients and its relation to the severity of the disease. COVID-19 patients as well as age and gender-matched healthy controls were enrolled in this study. The expression level of the antisense lncRNAs was measured by RT-PCR. Results revealed the decreased expression of A2M-AS1 and FLVCR1 in COVID-19 patients. Additionally, they showed the increased expression of DBH-AS1, FLVCR1-DT, and NCBP2AS2. Both FLVCR1-DT and NCBP2AS2 showed a positive correlation with interleukin-6 (IL-6). DBH-AS1 and FLVCR1-DT had a significant association with mortality, complications, and mechanical ventilation. A significant negative correlation was found between A2M-AS1 and NCBP2AS2-1 and between FLVCR1 and FLVCR1-DT. The study confirmed that the expression level of the antisense lncRNAs was deregulated in COVID-19 patients and correlated with the severity of COVID-19, and that it may have possible roles in the pathogenesis of this disease.
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Norepinephrine (NE), and specific adrenoceptors, have been reported to influence distinct aspects of adult hippocampal neurogenesis, including latent stem cell activation, progenitor proliferation, and differentiation. These findings are predominantly based on the use of pharmacological approaches in both in vitro and in vivo systems. Here, we sought to assess the consequences of genetic ablation of NE on adult hippocampal neurogenesis, by examining dopamine ß hydroxylase knockout (Dbh -/-) mice, which lack NE from birth. We find that Dbh -/- mice exhibit no difference in adult hippocampal progenitor proliferation and survival. Further, the number of immature newborn neurons, labeled using stage-specific developmental markers within the hippocampal neurogenic niche, was also unaltered in Dbh -/- mice. In contrast, the noradrenergic neurotoxin DSP-4, which had previously been shown to reduce adult hippocampal neurogenesis in rats, also resulted in a decline in hippocampal progenitor proliferation in C57/Bl6N mice. These findings indicate that pharmacological lesioning of noradrenergic afferents in adulthood, but not the complete genetic loss of NE from birth, impairs adult hippocampal neurogenesis in mice.
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AIM: Dopamine ß-hydroxylase (DBH) is a copper-containing enzyme that has an important role in maintaining the cellular homeostasis between the two neurotransmitters, dopamine (DA) and nor-adrenaline (NA). DBH functional polymorphisms are associated with multiple neuro-psychiatric conditions and are found to alter the DBH protein levels in serum affecting DBH enzymatic activity. The current study was conducted to determine the genetic and serum levels association of DBH rs1611115 functional polymorphism with major depressive disorder (MDD), bipolar disorder (BD) and schizophrenia (SHZ) in the Pakistani population. METHODS: In total n = 1097 subjects including MDD (n = 427), BD (n = 204), SHZ (n = 134) and healthy controls (n = 332), were screened for the functional polymorphism by polymerase chain reaction-restriction fragment length polymorphism. Univariate logistic regression analysis was applied and the results were adjusted for age and sex. The DBH levels in serum were determined through enzyme-linked immunosorbent assay (ELISA) and the Mann Whitney U test was applied. RESULTS: The minor allele (-1021 C > T) was found to be significantly associated with a higher risk of developing BD and SHZ in both univariable and multivariable analyses. The overall total serum concentration of DBH was comparatively raised in MDD, however, in cross-comparison DBH serum levels were found markedly higher in CC homozygotes compared to TT homozygotes within the BD group. CONCLUSION: The present study suggested a significant association of DBH rs1611115 with BD and SHZ and also the effect of rs1611115 on DBH serum levels in MDD and BD for the first time in the Pakistani population.
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The heteromeric assembly of α3 and ß4 subunits of acetylcholine nicotinic receptors (nAChRs) seems to mediate the secretory response in bovine chromaffin cells. However, there is no information about the localization of these nAChRs in relationship with the secretory active zones in this cellular model. The present work presents the first evidence that, in fact, a population of these receptors is associated through the F-actin cytoskeleton with exocytotic machinery components, as detected by SNAP-25 labeling. Furthermore, we also prove that, upon stimulation, the probability to find α3ß4 nAChRs very close to exocytotic events increases with randomized distributions, thus substantiating the clear dynamic behavior of these receptors during the secretory process. Modeling on secretory dynamics and secretory component distributions supports the idea that α3ß4 nAChR cluster mobility could help with improving the efficiency of the secretory response of chromaffin cells. Our study is limited by the use of conventional confocal microscopy; in this sense, a strengthening to our conclusions could come from the use of super-resolution microscopy techniques in the near future.
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Células Cromafines , Receptores Nicotínicos , Acetilcolina , Animales , Transporte Biológico , Bovinos , Células Cromafines/metabolismo , Antagonistas Nicotínicos , Receptores Nicotínicos/metabolismoRESUMEN
Destructively sampling old Pedunculate oak (Quercus robur) trees on the active floodplain of the Middle Elbe to create an allometric equation to estimate carbon stocks (CS) and carbon sequestration rates (CSR) would defeat the purpose of protecting increasingly vulnerable and threatened primeval floodplain forests. To nondestructively estimate CS and CSR, we have adapted a two-parameter allometric equation which uses tree height (H) and diameter at breast height (DBH) (Dik 1984, Zianis et al. 2005) into a 1-parameter equation that requires only DBH to quantify stocks and annual changes in carbon stock (carbon sequestration rates) for individual Q. robur trees. The equations have also been adapted to estimate below- and above-ground carbon stocks of individual trees. The new method has:â¢Adapted a 2-parameter Quercus robur allometric equation which estimates tree volume to a 1-parameter equation which estimates above and below-ground carbon stockâ¢Removed the requirement of tree height to reconstruct the carbon stock of trees at an annual timestepâ¢An almost perfect linear relationship (Pearson R2= 0.998) between carbon sequestration rate and basal area increment (BAI).
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Apurinic/apyrimidic (AP) sites are severe DNA damages and strongly block DNA extension by major DNA polymerases. Y-family DNA polymerases possess a strong ability to bypass AP sites and continue the DNA synthesis reaction, which is called translesion synthesis (TLS) activity. To investigate the effect of the molecular structure of the AP site on the TLS efficiency of Dbh, a Y-family DNA polymerase from Sulfolobus acidocaldarius, a series of different AP site analogues (various spacers) are used to characterize the bypass efficiency. We find that not only the molecular structure and atomic composition but also the number and position of AP site analogues determine the TLS efficiency of Dbh. Increasing the spacer length decreases TLS activity. The TLS efficiency also decreases when more than one spacer exists on the DNA template. The position of the AP site analogues is also an important factor for TLS. When the spacer is opposite to the first incorporated dNTPs, the TLS efficiency is the lowest, suggesting that AP sites are largely harmful for the formation of hydrogen bonds. These results deepen our understanding of the TLS activity of Y-family DNA polymerases and provide a biochemical basis for elucidating the TLS mechanism in Sulfolobus acidocaldarius cells.
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Sulfolobus acidocaldarius , ADN/química , Daño del ADN , Reparación del ADN , Replicación del ADN , ADN Polimerasa Dirigida por ADN/genética , Sulfolobus acidocaldarius/genética , Sulfolobus acidocaldarius/metabolismoRESUMEN
Exposure to unfamiliar odorants induces an array of repetitive defensive and non-defensive behaviors in rodents which likely reflect adaptive stress responses to the uncertain valence of novel stimuli. Mice genetically deficient for dopamine ß-hydroxylase (Dbh-/-) lack the enzyme required to convert dopamine (DA) into norepinephrine (NE), resulting in globally undetectable NE and supranormal DA levels. Because catecholamines modulate novelty detection and reactivity, we investigated the effects of novel plant-derived odorants on repetitive behaviors in Dbh-/- mice and Dbh+/- littermate controls, which have catecholamine levels comparable to wild-type mice. Unlike Dbh+/- controls, which exhibited vigorous digging in response to novel odorants, Dbh-/- mice displayed excessive grooming. Drugs that block NE synthesis or neurotransmission suppressed odorant-induced digging in Dbh+/- mice, while a DA receptor antagonist attenuated grooming in Dbh-/- mice. The testing paradigm elicited high circulating levels of corticosterone regardless of Dbh genotype, indicating that NE is dispensable for this systemic stress response. Odorant exposure increased NE and DA abundance in the prefrontal cortex (PFC) of Dbh+/- mice, while Dbh-/- animals lacked NE and had elevated PFC DA levels that were unaffected by novel smells. Together, these findings suggest that novel odorant-induced increases in central NE tone contribute to repetitive digging and reflect psychological stress, while central DA signaling contributes to repetitive grooming. Further, we have established a simple method for repeated assessment of stress-induced repetitive behaviors in mice, which may be relevant for modeling neuropsychiatric disorders like Tourette syndrome or obsessive-compulsive disorder that are characterized by stress-induced exacerbation of compulsive symptoms.