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41.
Haloperidol is the most widely used antipsychotic drug in the treatment of psychiatric disorders. Despite its satisfactory therapeutic effect, its chronic use is related to severe motor side effects. Here, we investigate the incidence of motor side effects of haloperidol-loaded nanocapsules when compared to free haloperidol and the relation with oxidative stress (OS) development. Both vehicle (B-NcFO) and haloperidol loaded polysorbate-coated nanocapsules suspension (H-NcFO) prepared with fish oil as core showed uniform and rounded particles, nanometric size, negative zeta potential, low polydispersity indices and high encapsulation efficiency. Wistar rats received a single dose of free haloperidol (FH), B-NcFO or H-NcFO (0.2mg/kg ip) and were submitted to acute motor side effects evaluation 1h after the injection. Lower catalepsy time and oral dyskinesia were observed in H-NcFO-treated group than in FH group; however, both formulations decreased animals' locomotor activity. In a experiment performed subchronically, rats injected daily with H-NcFO (0.2mg/kg-ip) for 28days showed decreased oral dyskinesia frequency and catalepsy time and no impairment on locomotor activity as compared to FH group (0.2mg/kg-ip). FH group showed higher OS, as observed by increased lipid peroxidation and reduced glutathione levels and catalase activity in extrapyramidal region. Our findings showed that nanocapsules may be an efficient form to prevent or minimize haloperidol motor side effects, which are related to OS development, ameliorating psychiatric patients' quality of life.  相似文献   
42.
Crypt cells—one of the three cell types composing Strombidae digestive tubules—are characterized by the presence of numerous metal-containing phosphate granules termed spherocrystals. We explored the bioaccumulation and detoxification of metals in Strombidae by exposing wild fighting conch Strombus pugilis for 9 days to waterborne CuSO4 and ZnSO4. The total amount of Cu and Zn was determined in the digestive gland and in the rest of the body by Inductively Coupled Plasma (ICP) analyses. The digestive gland spherocrystal metal content was investigated based on the semi-quantitative energy dispersive X-ray (EDX) elemental analysis. ICP analyses of unexposed individuals revealed that 87.0?±?5.9% of the Zn is contained in the digestive gland, where its concentration is 36 times higher than in the rest of the body. Regarding Cu, 25.8?±?16.4% of the metal was located in the digestive gland of the control individuals, increasing to 61.5?±?16.4% in exposed individuals. Both Cu and Zn concentrations in the digestive gland increased after exposures, pointing to a potential role of this organ in the detoxification of these metals. EDX analysis of spherocrystals revealed the presence of Ca, Cl, Fe, K, Mg, P, and Zn in unexposed individuals. No difference was found in the relative proportion of Zn in spherocrystals of exposed versus control individuals. Contrastingly, copper was never detected in the spherocrystals from controls and Zn-exposed individuals, but the relative proportion of Cu in spherocrystals of Cu-exposed individuals varied from 0.3 to 5.7%. Our results show the direct role of spherocrystals in Cu detoxification.  相似文献   
43.
The mechanisms of persistence and virulence associated with Candida glabrata infections are poorly understood, limiting the ability to fight this fungal pathogen. In this study, the multidrug resistance transporters CgTpo1_1 and CgTpo1_2 are shown to play a role in C. glabrata virulence. The survival of the infection model Galleria mellonella, infected with C. glabrata, was found to increase upon the deletion of either CgTPO1_1 or CgTPO1_2. The underlying mechanisms were further explored. In the case of CgTpo1_1, this phenotype was found to be consistent with the observation that it confers resistance to antimicrobial peptides (AMP), such as the human AMP histatin‐5. The deletion of CgTPO1_2, on the other hand, was found to limit the survival of C. glabrata cells when exposed to phagocytosis and impair biofilm formation. Interestingly, CgTPO1_2 expression was found to be up‐regulated during biofilm formation, but and its deletion leads to a decreased expression of adhesin‐encoding genes during biofilm formation, which is consistent with a role in biofilm formation. CgTPO1_2 expression was further seen to decrease plasma membrane potential and affect ergosterol and fatty acid content. Altogether, CgTpo1_1 and CgTpo1_2 appear to play an important role in the virulence of C. glabrata infections, being at the cross‐road between multidrug resistance and pathogenesis.  相似文献   
44.

Background

Several genomes have now been sequenced, with millions of genetic variants annotated. While significant progress has been made in mapping single nucleotide polymorphisms (SNPs) and small (<10 bp) insertion/deletions (indels), the annotation of larger structural variants has been less comprehensive. It is still unclear to what extent a typical genome differs from the reference assembly, and the analysis of the genomes sequenced to date have shown varying results for copy number variation (CNV) and inversions.

Results

We have combined computational re-analysis of existing whole genome sequence data with novel microarray-based analysis, and detect 12,178 structural variants covering 40.6 Mb that were not reported in the initial sequencing of the first published personal genome. We estimate a total non-SNP variation content of 48.8 Mb in a single genome. Our results indicate that this genome differs from the consensus reference sequence by approximately 1.2% when considering indels/CNVs, 0.1% by SNPs and approximately 0.3% by inversions. The structural variants impact 4,867 genes, and >24% of structural variants would not be imputed by SNP-association.

Conclusions

Our results indicate that a large number of structural variants have been unreported in the individual genomes published to date. This significant extent and complexity of structural variants, as well as the growing recognition of their medical relevance, necessitate they be actively studied in health-related analyses of personal genomes. The new catalogue of structural variants generated for this genome provides a crucial resource for future comparison studies.  相似文献   
45.
It has been suggested that the absence or altered structure of Dp71, a C-terminal dystrophin gene encoded protein, is responsible for mental alterations observed in about 30% of Duchenne muscular dystrophy patients. Most of these patients have premature translational termination or point mutations at the C-terminal domain of this gene. In brain, Dp71 is the major protein product of the dystrophin gene. To determine the function of Dp71 isoforms in this organ, it is important to document their presence and intracellular localization in brain cells. Extracts from cultured hippocampal neurons and forebrain astrocytes and 5F3 and Dys 2 monoclonal antibodies were thus used for western blots. In these conditions, two Dp71 isoforms spliced or not at exon 78 were detected in both cells (Dp71f and Dp71d, respectively). By immunocytochemistry, we mapped Dp71f and Dp71d in the Golgi complex (GC) and in neuronal nuclei. Only Dp71d was found in cytoplasmic neurofilaments. In astrocytes, these isoforms were detected in the GC. These cell localization data suggest that these Dp71 isoforms may have different functions in the same cell or organelle, as well as in the two different cells analyzed.  相似文献   
46.
Summary An improved method for separating transferrin subtypes through the use of isoelectric focusing on ultrathin layer polyacrylamide gels is described. The most considerable problems encountered in the assessment of the Tf phenotypes after pretreatment with iron donor compounds are pointed out. Useful technical devices for reducing the occurrence of artifactitious extrabands are suggested. Finally, the gene frequencies in three samples from Italian populations are reported.  相似文献   
47.
Calreticulin (CALR) mutations have recently been reported in 70–84% of JAK2V617F-negative myeloproliferative neoplasms (MPN), and this detection has become necessary to improve the diagnosis of MPN. In a large single-centre cohort of 298 patients suffering from Essential Thrombocythemia (ET), the JAK2V617F, CALR and MPL mutations were noted in 179 (60%), 56 (18.5%) and 13 (4.5%) respectively. For the detection of the CALR mutations, three methods were compared in parallel: high-resolution melting-curve analysis (HRM), product-sizing analysis and Sanger sequencing. The sensitivity for the HRM, product-sizing analysis and Sanger sequencing was 96.4%, 98.2% and 89.3% respectively, whereas the specificity was 96.3%, 100% and 100%. In our cohort, the product-sizing analysis was the most sensitive method and was the easiest to interpret, while the HRM was sometimes difficult to interpret. In contrast, when large series of samples were tested, HRM provided results more quickly than did the other methods, which required more time. Finally, the sequencing method, which is the reference method, had the lowest sensitivity but can be used to describe the type of mutation precisely. Altogether, our results suggest that in routine laboratory practice, product-sizing analysis is globally similar to HRM for the detection of CALR mutations, and that both may be used as first-line screening tests. If the results are positive, Sanger sequencing can be used to confirm the mutation and to determine its type. Product-sizing analysis provides sensitive and specific results, moreover, with the quantitative measurement of CALR, which might be useful to monitor specific treatments.  相似文献   
48.
During an annual cycle, overlying water and sediment cores were collected simultaneously at three sites (Tavira, Culatra and Ramalhete) of Ria Formosa’s intertidal muddy and subtidal sandy sediments to determine ammonium, nitrates plus nitrites and phosphate. Organic carbon, nitrogen and phosphorus were also determined in superficial sediments. Ammonium and phosphate dissolved in porewater were positively correlated with temperature (P < 0.01) in muddy and sandy sediments, while the nitrogen-oxidized forms had a negative correlation (P < 0.02) in muddy sediments probably because mineralization and nitrification/denitrification processes vary seasonally. Porewater ammonium profiles evidenced a peak in the top-most muddy sediment (380 μM) suggesting higher mineralization rate when oxygen is more available, while maximum phosphate concentration (113 μM) occurred in the sub-oxic layer probably due to phosphorus desorption under reduced conditions. In organically poor subtidal sandy sediments, nutrient porewater concentrations were always lower than in intertidal muddy sediments, ranging annually from 20 μM to 100 μM for ammonium and from 0.05 μM to 16 μM for phosphate. Nutrient diffusive fluxes predicted by a mathematical model were higher during summer, in both muddy (104 nmol cm−2 d−1––NH4+; 8 nmol cm−2 d−1––HPO4−2) and sandy sediments (26 nmol cm−2 d−1––NH4+; 1 nmol cm−2 d−1––HPO4−2), while during lower temperature periods these fluxes were 3–4 times lower. Based on simulated nutrient effluxes, the estimated annual amount of ammonium and phosphate exported from intertidal areas was three times higher than that released from subtidal areas (22 ton year−1––NH4+; 2 ton year−1––HPO4−2), emphasizing the importance of tidal flats to maintain the high productivity of the lagoon. Global warming scenarios simulated with the model, revealed that an increase in lagoon water temperature only produces significant variations (P < 0.05) for NH4+ in porewater and consequent diffusive fluxes, what will probably affect the system productivity due to a N/P ratio unbalance.  相似文献   
49.
Human type 5 17beta-hydroxysteroid dehydrogenase plays a crucial role in local androgen formation in prostate tissue. Several chemicals were synthesized and tested for their ability to inhibit this enzyme, and a series of estradiol derivatives bearing a lactone on the D-ring were found to inhibit its activity efficiently. The crystal structure of the type 5 enzyme in complex with NADP and such a novel inhibitor, EM1404, was determined to a resolution of 1.30 A. Significantly more hydrogen bonding and hydrophobic interactions were defined between EM1404 and the enzyme than in the substrate ternary complex. The lactone ring of EM1404 accounts for important interactions with the enzyme, whereas the amide group at the opposite end of the inhibitor contributes to the stability of three protein loops involved in the construction of the substrate binding site. EM1404 has a strong competitive inhibition, with a Ki of 6.9+/-1.4 nM, demonstrating 40 times higher affinity than that of the best inhibitor previously reported. This is observed despite the fact that the inhibitor occupies only part of the binding cavity. Attempts to soak the inhibitor into crystals of the binary complex with NADP were unsuccessful, yielding a structure with a polyethylene glycol fragment occupying the substrate binding site. The relative crystal packing is discussed. Combined studies of small molecule inhibitor synthesis, x-ray crystallography, enzyme inhibition, and molecular modeling make it possible to analyze the plasticity of the substrate binding site of the enzyme, which is essential for developing more potent and specific inhibitors for hormone-dependent cancer therapy.  相似文献   
50.
Contribution of SHANK3 mutations to autism spectrum disorder   总被引:3,自引:0,他引:3       下载免费PDF全文
Mutations in SHANK3, which encodes a synaptic scaffolding protein, have been described in subjects with an autism spectrum disorder (ASD). To assess the quantitative contribution of SHANK3 to the pathogenesis of autism, we determined the frequency of DNA sequence and copy-number variants in this gene in 400 ASD-affected subjects ascertained in Canada. One de novo mutation and two gene deletions were discovered, indicating a contribution of 0.75% in this cohort. One additional SHANK3 deletion was characterized in two ASD-affected siblings from another collection, which brings the total number of published mutations in unrelated ASD-affected families to seven. The combined data provide support that haploinsufficiency of SHANK3 can cause a monogenic form of autism in sufficient frequency to warrant consideration in clinical diagnostic testing.  相似文献   
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