4,113 research outputs found
Structural properties of the linkers connecting the n- and c- terminal domains in the mocr bacterial transcriptional regulators
Peptide inter-domain linkers are peptide segments covalently linking two adjacent domains within a protein. Linkers play a variety of structural and functional roles in naturally occurring proteins. In this work we analyze the sequence properties of the predicted linker regions of the bacterial transcriptional regulators belonging to the recently discovered MocR subfamily of the GntR regulators. Analyses were carried out on the MocR sequences taken from the phyla Actinobacteria, Firmicutes, Alpha-, Beta- and Gammaproteobacteria. The results suggest that MocR linkers display phylum-specific characteristics and unique features different from those already described for other classes of inter-domain linkers. They show an average length significantly higher: 31.8 ± 14.3 residues reaching a maximum of about 150 residues. Compositional propensities displayed general and phylum-specific trends. Pro is dominating in all linkers. Dyad propensity analysis indicate Pro–Pro as the most frequent amino acid pair in all linkers. Physicochemical properties of the linker regions were assessed using amino acid indices relative to different features: in general, MocR linkers are flexible, hydrophilic and display propensity for β-turn or coil conformations. Linker sequences are hypervariable: only similarities between MocR linkers from organisms related at the level of species or genus could be found with sequence searches. The results shed light on the properties of the linker regions of the new MocR subfamily of bacterial regulators and may provide knowledge-based rules for designing artificial linkers with desired properties. © 2016 The Author(s
Impact of Lentiviral Vector-Mediated Transduction on the Tightness of a Polarized Model of Airway Epithelium and Effect of Cationic Polymer Polyethylenimine
Lentiviral (LV) vectors are promising agents for efficient and long-lasting gene transfer into the lung and for gene therapy of genetically determined pulmonary diseases, such as cystic fibrosis, however, they have not been evaluated for cytotoxicity and impact on the tightness of the airway epithelium. In this study, we evaluated the transduction efficiency of a last-generation LV vector bearing Green Fluorescent Protein (GFP) gene as well as cytotoxicity and tight junction (TJ) integrity in a polarized model of airway epithelial cells. High multiplicities of infection (MOI) showed to be cytotoxic, as assessed by increase in propidium iodide staining and decrease in cell viability, and harmful for the epithelial tightness, as demonstrated by the decrease of transepithelial resistance (TER) and delocalization of occludin from the TJs. To increase LV efficiency at low LV:cell ratio, we employed noncovalent association with the polycation branched 25 kDa polyethylenimine (PEI). Transduction of cells with PEI/LV particles resulted in 2.5–3.6-fold increase of percentage of GFP-positive cells only at the highest PEI:LV ratios (1×107 PEI molecules/transducing units with 50 MOI LV) as compared to plain LV. At this dose PEI/LV transduction resulted in 6.5 ± 2.4% of propidium iodide-positive cells. On the other hand, PEI/LV particles did not determine any alteration of TER and occludin localization. We conclude that PEI may be useful for improving the efficiency of gene transfer mediated by LV vectors in airway epithelial cells, in the absence of high acute cytotoxicity and alteration in epithelial tightness
Chitosan-Based Nanoparticles Containing Cherry Extract from Prunus avium L. to Improve the Resistance of Endothelial Cells to Oxidative Stress
Cherries are known for their nutraceutical properties, in particular for their antioxidant ability due to their polyphenol content, which causes a reduction of cardiovascular disease (CVD) risk factors. However, once ingested these molecules are degraded in the Gastrointestinal (GI) tract before reaching the blood, which is the action site. The object of the present work is to evaluate the ability of cherry extract (CE), encapsulated in nanoparticles (NPs) based on different chitosan (Ch) derivatives, to promote a protective effect of human umbilical vein endothelial cells (HUVECs) involved in vascular dysfunction against oxidative stress. CE-loaded NPs based on quaternary ammonium chitosan (NP1) and an S-protected thiolated derivative thereof (NP2) were prepared. The mean particle size (NP1 344.9 ± 17.8, NP2 339.9 ± 68.2 nm), the polydispersity index, the encapsulation efficiency (NP1 78.4 ± 4.5, NP2 79.8 ± 0.6%), and the zeta potential (NP1 14.8 ± 0.3, NP2 15.8 ± 0.5 mV) did not appear to be significantly different. Both NP types improved the CE apparent permeation parameters with respect to the control. Conversely, CE-loaded NP2 protected HUVECs from oxidative stress and reduced reactive oxygen species (ROS) production more than CE-loaded NP1 and free CE. In addition to promoting HUVEC resistance, NP2 could be a useful tool to overcome the problem of cherry seasonality
Saphenous and Sciatic Nerve Blockade with and without Obturator Nerve Block for Tibial Plateau Levelling Osteotomy Surgery in Dogs: A Randomized Controlled Trial
Simple Summary Locoregional anaesthesia plays a fundamental role in the correct management of surgical interventions. Veterinary ultrasound-guided techniques are in continuous evolution to obtain adequate analgesia with minimal motor impact. We hypothesized that the block of the obturator nerve in the inguinal compartment, combined with the block of the saphenous and the sciatic nerves, without the block of the femoral nerve, could produce analgesia with less motor function impairment for tibial-plateau-levelling-osteotomy (TPLO) surgery. Having easily identified a window during the anatomical study that included an inguinal approach, we could correctly perform this new ultrasound-guided obturator-nerve-block technique. Patients that received three blocks with ropivacaine had statistically significantly less need for rescue analgesia during surgery than those that received saline solution at the level of the obturator nerve. In the group that did not receive ropivacaine for the obturator nerve block, nociception occurred in almost all patients at the time of incision of the joint capsule, showing the obturator nerve role in the innervation of the knee joint. The use of this new technique in association with the block of the sciatic and saphenous nerves represents an improvement in locoregional techniques in knee surgery, as the patient not only has a reduction in intraoperative nociception but also has better postoperative mobility, resulting from the fact that the femoral nerve, which is responsible for the innervation of the quadriceps muscles, was not blocked.Abstract The objective of our study was to compare the efficacy of sciatic and saphenous ultrasound nerve blocks with and without US-guided obturator nerve block in dogs undergoing tibial-plateau-levelling-osteotomy (TPLO) surgery. This study was developed in two phases: identification of an ultrasound window in the inguinal region for obturator nerve block and utilization of it in dogs undergoing TPLO. Dogs were assigned randomly to one of two groups: one received the three blocks with 0.5% ropivacaine (ON group) and the second one (NoON group) with NaCl instead of ropivacaine for the obturator block. In phase 1, the obturator nerve was visible between the pectineus and the abductor muscles and was approached using an in-plane technique. It was possible to use the ultrasound window for phase two. The number of dogs that received at least one bolus of intraoperative rescue analgesia in the NoON group (12/15 dogs) was significantly higher (p = 0.003) in comparison with the ON group (4/15). An ultrasound window to block the obturator nerve in the inguinal compartment with an in-plane technique was found. The use of this approach could produce adequate analgesia with less motor function impairment in dogs for TPLO surgery
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Ca2+-activated K+ channels modulate microglia affecting motor neuron survivalin hSOD1G93A mice
Recent studies described a critical role for microglia in amyotrophic lateral sclerosis (ALS), where these CNS-resident immune cells participate in the establishment of an inflammatory microenvironment that contributes to motor neuron degeneration. Understanding the mechanisms leading to microglia activation in ALS could help to identify specific molecular pathways which could be targeted to reduce or delay motor neuron degeneration and muscle paralysis in patients. The intermediate-conductance calcium-activated potassium channel KCa3.1 has been reported to modulate the "pro-inflammatory" phenotype of microglia in different pathological conditions. We here investigated the effects of blocking KCa3.1 activity in the hSOD1G93AALS mouse model, which recapitulates many features of the human disease. We report that treatment of hSOD1G93A mice with a selective KCa3.1 inhibitor, 1-[(2-chlorophenyl)diphenylmethyl]-1H-pyrazole (TRAM-34), attenuates the "pro-inflammatory" phenotype of microglia in the spinal cord, reduces motor neuron death, delays onset of muscle weakness, and increases survival. Specifically, inhibition of KCa3.1 channels slowed muscle denervation, decreased the expression of the fetal acetylcholine receptor γ subunit and reduced neuromuscular junction damage. Taken together, these results demonstrate a key role for KCa3.1 in driving a pro-inflammatory microglia phenotype in ALS
Relationship among Milk Conductivity, Production Traits, and Somatic Cell Score in the Italian Mediterranean Buffalo
The measurement of milk electrical conductivity (EC) is a relatively simple and inexpensive technique that has been evaluated as a routine method for the diagnosis of mastitis in dairy farms. The aim of this study was to obtain further knowledge on relationships between EC, production traits and somatic cell count (SCC) in Italian Mediterranean Buffalo. The original dataset included 5411 records collected from 808 buffalo cows. Two mixed models were used to evaluate both the effect of EC on MY, PP and FP and EC at test-day, and the effect of EC on somatic cell score (SCS) by using five different parameters (EC_param), namely: EC collected at the official milk recording test day (EC_day0), EC collected 3 days before official milk recording (EC_day3), and three statistics calculated from EC collected 1, 3 and 5 days before each test-day, respectively. All effects included in the model were significant for all traits, with the only exception of the effect of EC nested within parity for FP. The relationship between EC and SCS was always positive, but of different magnitude according to the parity. The regression of EC on SCS at test-day using different EC parameters was always significant except when the regression parameter was the slope obtained from a linear regression of EC collected over the 5-day period. Moreover, in order to evaluate how well the different models fit the data, three parameters were used: the Average Information Criteria (AIC), the marginal R2 and the conditional R2. According to AIC and to both the Marginal and Conditional R2, the best results were obtained when the regression parameter was the mean EC estimated over the 5-day period
Onset and Progression of Precancerous Lesions on Gastric Mucosa of Patients Treated for Gastric Lymphoma.
Background and Aims: Patients with primary gastric lymphoma are at an increased risk of developing gastric cancer. Data on gastric precancerous lesions development in these patients are scanty. We assessed gastric precancerous lesions in a cohort of patients with primary lymphoma.
Methods: Data of patients with primary gastric lymphoma [mucosa-associated lymphoid tissue (MALT)- lymphoma or diffuse large B-cell lymphoma (DLBCL)] were analysed. Multiple (>10) biopsies were performed on gastric mucosa at each endoscopic control, beyond macroscopic lesions. Presence and distribution of intestinal metaplasia (IM) at baseline, the onset at follow-up, and progression through the stomach or transformation in the incomplete IM type were assessed. The onset of neoplastic lesions was recorded.
Results: Data of 50 patients (mean age of 63.6 ± 10.7 years; M/F: 25/25), including 40 with MALT-lymphoma and 10 with DLBCL, with median follow-up of 30.5 months (range: 9-108) and a median of 6 endoscopic controls (range: 3-14) were evaluated. At entry, IM was present in 12 (24%), and it developed in other 22 (57.9%) patients at a median follow-up of 6 (range: 3-40) months. Overall, progression of IM was observed in 7 (21.2%) cases, including extension in the stomach (n=5) or transformation into the incomplete type (n=2). Low-grade dysplasia was detected in 4, and indefinite dysplasia in other 7 patients. In one patient, low-grade dysplasia had progressed to high-grade and gastric adenocarcinoma of the fundus.
Conclusions: Our data found a frequent onset and rapid progression of precancerous lesions on gastric mucosa of lymphoma patients. This observation could explain the increased incidence of metachronous gastric cancer in these patients
Non-Aβ-dependent factors associated with global cognitive and physical function in alzheimer's disease: a pilot multivariate analysis
Recent literature highlights the importance of identifying factors associated with mild cognitive impairment (MCI) and Alzheimer's Disease (AD). Actual validated biomarkers include neuroimaging and cerebrospinal fluid assessments; however, we investigated non-Aβ-dependent factors associated with dementia in 12 MCI and 30 AD patients. Patients were assessed for global cognitive function (Mini-Mental state examination-MMSE), physical function (Physical Performance Test-PPT), exercise capacity (6-min walking test-6MWT), maximal oxygen uptake (VO₂max), brain volume, vascular function (flow-mediated dilation-FMD), inflammatory status (tumor necrosis factor-α ,TNF- α, interleukin-6, -10 and -15) and neurotrophin receptors (p75NTR and Tropomyosin receptor kinase A -TrkA). Baseline multifactorial information was submitted to two separate backward stepwise regression analyses to identify the variables associated with cognitive and physical decline in demented patients. A multivariate regression was then applied to verify the stepwise regression. The results indicated that the combination of 6MWT and VO₂max was associated with both global cognitive and physical function (MMSE = 11.384 + (0.00599 × 6MWT) - (0.235 × VO₂max)); (PPT = 1.848 + (0.0264 × 6MWT) + (19.693 × VO₂max)). These results may offer important information that might help to identify specific targets for therapeutic strategies (NIH Clinical trial identification number NCT03034746)
Identification of GOLPH3 Partners in Drosophila Unveils Potential Novel Roles in Tumorigenesis and Neural Disorders.
Golgi phosphoprotein 3 (GOLPH3) is a highly conserved peripheral membrane protein localized to the Golgi apparatus and the cytosol. GOLPH3 binding to Golgi membranes depends on phosphatidylinositol 4-phosphate [PI(4)P] and regulates Golgi architecture and vesicle trafficking. GOLPH3 overexpression has been correlated with poor prognosis in several cancers, but the molecular mechanisms that link GOLPH3 to malignant transformation are poorly understood. We recently showed that PI(4)P-GOLPH3 couples membrane trafficking with contractile ring assembly during cytokinesis in dividing Drosophila spermatocytes. Here, we use affinity purification coupled with mass spectrometry (AP-MS) to identify the protein-protein interaction network (interactome) of Drosophila GOLPH3 in testes. Analysis of the GOLPH3 interactome revealed enrichment for proteins involved in vesicle-mediated trafficking, cell proliferation and cytoskeleton dynamics. In particular, we found that dGOLPH3 interacts with the Drosophila orthologs of Fragile X mental retardation protein and Ataxin-2, suggesting a potential role in the pathophysiology of disorders of the nervous system. Our findings suggest novel molecular targets associated with GOLPH3 that might be relevant for therapeutic intervention in cancers and other human diseases
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Identification of GOLPH3 Partners in <i>Drosophila</i> Unveils Potential Novel Roles in Tumorigenesis and Neural Disorders.
Golgi phosphoprotein 3 (GOLPH3) is a highly conserved peripheral membrane protein localized to the Golgi apparatus and the cytosol. GOLPH3 binding to Golgi membranes depends on phosphatidylinositol 4-phosphate [PI(4)P] and regulates Golgi architecture and vesicle trafficking. GOLPH3 overexpression has been correlated with poor prognosis in several cancers, but the molecular mechanisms that link GOLPH3 to malignant transformation are poorly understood. We recently showed that PI(4)P-GOLPH3 couples membrane trafficking with contractile ring assembly during cytokinesis in dividing Drosophila spermatocytes. Here, we use affinity purification coupled with mass spectrometry (AP-MS) to identify the protein-protein interaction network (interactome) of Drosophila GOLPH3 in testes. Analysis of the GOLPH3 interactome revealed enrichment for proteins involved in vesicle-mediated trafficking, cell proliferation and cytoskeleton dynamics. In particular, we found that dGOLPH3 interacts with the Drosophila orthologs of Fragile X mental retardation protein and Ataxin-2, suggesting a potential role in the pathophysiology of disorders of the nervous system. Our findings suggest novel molecular targets associated with GOLPH3 that might be relevant for therapeutic intervention in cancers and other human diseases
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