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Ethanol has been used to achieve thymic depletion in myasthenia gravis patients. Ethanol (95%) has also been used widely in the therapy of many tumors including hepatocellular carcinoma. In light of these findings, we delineated the differential immunotoxic behavior and mechanism of lower concentration of ethanol towards murine EL-4 lymphoma and its normal counterpart lymphocytes. EL-4 lymphoma and normal lymphocytes were cultured with ethanol (0%-5%) for 6?h and cytotoxicity was measured by various methods. EL-4 cells treated with ethanol showed concentration-dependent loss of viability at 2%-5% ethanol concentration and exhibit proliferative arrest at preG1 stage. Acridine-orange and ethidium-bromide staining indicated that ethanol induced death in EL-4 cells, by induction of both apoptosis and necrosis which was further supported by findings of DNA-fragmentation and trypan blue dye exclusion test. However, treatment of lymphocytes with similar concentration of ethanol did not show any death-associated parameters. Furthermore, ethanol induced significantly higher ROS generation in EL-4 cells as compared to lymphocytes and caused PARP cleavage and activation of apoptotic proteins like p53 and Bax, in EL-4 cells and not in normal lymphocytes. In addition, ethanol exposure to EL-4 cells led to phosphorylation of p38MAPK, and upregulation of death receptor Fas (CD95). Taken together, these results suggest that ethanol upto a concentration of 5% caused no significant immunotoxicity towards normal lymphocytes and induced cell death in EL-4 cells via phosphorylation of p38MAPK and regulation of p53 leading to further activation of both extrinsic (Fas) and intrinsic (Bax) apoptotic markers.  相似文献   
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Understanding electronic structure at the nanoscale is crucial to untangling fundamental physics puzzles such as phase separation and emergent behavior in complex magnetic oxides. Probes with the ability to see beyond surfaces on nanometer length and subpicosecond time scales can greatly enhance our understanding of these systems and will undoubtedly impact development of future information technologies. Polarized X-rays are an appealing choice of probe due to their penetrating power, elemental and magnetic specificity, and high spatial resolution. The resolution of traditional X-ray microscopes is limited by the nanometer precision required to fabricate X-ray optics. Here we present a novel approach to lensless imaging of an extended magnetic nanostructure, in which a scanned series of dichroic coherent diffraction patterns is recorded and numerically inverted to map its magnetic domain configuration. Unlike holographic methods, it does not require a reference wave or precision optics. In addition, it enables the imaging of samples with arbitrarily large spatial dimensions, at a spatial resolution limited solely by the coherent X-ray flux, wavelength, and stability of the sample with respect to the beam. It can readily be extended to nonmagnetic systems that exhibit circular or linear dichroism. We demonstrate this approach by imaging ferrimagnetic labyrinthine domains in a Gd/Fe multilayer with perpendicular anisotropy and follow the evolution of the domain structure through part of its magnetization hysteresis loop. This approach is scalable to imaging with diffraction-limited resolution, a prospect rapidly becoming a reality in view of the new generation of phenomenally brilliant X-ray sources.  相似文献   
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Hyperammonemic encephalopathy is a type of metabolic encephalopathy with diversified etiology. Hyperammonemia is the end result of several metabolic disorders such as congenital deficiencies of urea cycle enzymes, hepatic encephalopathy, Reye's syndrome and other toxic encephalopathies. Non-specific clinical presentation poses a great challenge in early diagnosis of this entity. Irrespective of the underlying etiology, hyperammonemia causes a distinctive pattern of brain parenchymal injury. The cingulate gyrus and insular cortex are more vulnerable to this type of toxic insult. Characteristic magnetic resonance imaging findings in combination with laboratory parameters can help to differentiate this entity from other metabolic encephalopathy and thus aiding in early diagnosis and treatment.  相似文献   
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Honey-bee bites which require urgent hospitalization is very rare. It is mainly seen as occupational hazards in farmers, tree dwellers and honey collectors. Common clinical presentation includes minor localized reactions in form of swelling and redness sometimes anaphylactic reaction. Infrequent major complications reported from different studies include rhabdomyolysis, acute renal failure (ARF), acute pulmonary edema, intravascular coagulation, encephalopathy and very rarely cerebral haemorrhage. Stroke due to multiple intra- cerebral infarcts along with rhabdomyolysis in patient of honey-bee bite is rare neurological complication. We report a case of 70 year man with honey-bee bite and multiple intracerebral infarcts presented as stroke, and rhabdomyolysis and ARF. When a patient presented with honey-bee bite, one should suspect serious complications. Despite advances in the understanding of pathophysiology its complications remains enigmatic and in some instances may be multifactorial. Various therapeutic interventions if started early after diagnosis reduces the possible consequences as potential reversibility of the illness.  相似文献   
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Purpose

This study aimed to investigate the association between target volume margins and clinical outcomes for patients with inoperable non-small cell lung cancer (NSCLC) treated with concurrent chemoradiation therapy.

Methods and materials

We reviewed the records of 82 patients with inoperable NSCLC treated between 2009 and 2016 with concurrent chemoradiation. All patients received positron emission tomography–based treatment planning, 4-dimensional computed tomography simulation to define an internal target volume, and daily cone beam computed tomography. We quantified variations in target volume margins with a margin deviation index (MDI), calculated as the percentage change in equivalent uniform dose between the original planning target volume (PTV) and a standard reference PTV 10 mm beyond the original gross tumor volume, consistent with the minimum margins mandated by recent NSCLC trials. Greater MDIs equated to smaller effective target volume margins. We dichotomized patients by the upper tercile MDI value (5.8%). Endpoints included time to locoregional progression and time to grade ≥ 3 radiation esophagitis (RE3) or radiation pneumonitis (RP3), modelled with the Fine-Gray method.

Results

Median follow-up was 37.8 months (range, 5.9-58.1 months). Larger MDIs correlated with smaller clinical target volume (CTV) + PTV margins, larger gross tumor volumes, later treatment year, and intensity modulated radiation therapy use. The risk of locoregional progression did not differ for MDI ≥5.8% versus <5.8% (adjusted hazard ratio: 0.88; P = .76), but the risk of RE3 or RP3 was decreased for MDI ≥5.8% (adjusted hazard ratio: 0.27; P = .027). Patients with MDI ≥5.8% were treated with smaller CTV + PTV margins (median, 5.6 vs 8 mm; P < .0001) and a marginally lower volume of esophagus receiving ≥50 Gy (median, 31.1% vs 35.3%; P = .069).

Conclusions

Smaller margins were used for larger tumors but were not associated with an increase in locoregional failures. Additional studies could clarify whether smaller margins, when used alongside modern radiation therapy techniques, decrease treatment-related toxicity for inoperable NSCLC.  相似文献   
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