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1.
J Mol Graph Model ; 131: 108793, 2024 Sep.
Article in English | MEDLINE | ID: mdl-38797086

ABSTRACT

The welding process and the properties of welding instruments may improve the mechanical performance of an item. One of these properties is the length of the welding tool. This approach has a substantial effect on the mechanical strength of the metallic matrix. The current study used molecular dynamics modeling and LAMMPS software to evaluate the effect of welding tool length on the mechanical properties of a welded Cu-Ag metallic matrix. This simulation makes use of the Lennard-Jones potential function and the embedded atom model. First, the equilibrium phase of modeled samples was verified by changing the computation of kinetic and total energies. Next, the mechanical properties of the welded matrix were studied using the stated Young's modulus and ultimate strength. The stress-strain curve of samples demonstrated that the mechanical strength of atomic samples increased as the length of the welding tool (penetration depth) increased. Numerically, by increasing the tool penetration depth of Fe tools from 2 Å to 8 Å, Young's modulus and ultimate strength of the matrixes sample increase from 34.360 GPa to 1390.84 MPa to 38.44 GPa and 1510 MPa, respectively. This suggested that the length of the Fe welding tool significantly affected the mechanical properties of the welded metallic matrix. The longer the length of Fe welding tools, the more particles were involved, and consequently, more bonds were formed among the particles. Bonding among the particles caused changes in mechanical properties, such as greater ultimate strength. This method can optimize mechanical structures and be useful in various industries.


Subject(s)
Molecular Dynamics Simulation , Welding , Welding/methods , Elastic Modulus , Metals/chemistry , Stress, Mechanical , Mechanical Phenomena , Copper/chemistry
2.
Sci Rep ; 13(1): 19046, 2023 11 03.
Article in English | MEDLINE | ID: mdl-37923828

ABSTRACT

Worldwide mortality from hepatic fibrosis remains high, due to hepatocellular carcinoma and end stage liver failure. The progressive nature of hepatic fibrosis from inflammation to cicatrized tissues warrants subtle intervention with pharmacological agents that hold potential. Empagliflozin (Empa), a novel hypoglycemic drug with antioxidant and anti-inflammatory properties, has lately been proposed to have additional antifibrotic activities. In the current study, we examined the antifibrotic effect of the Empa through modulating the activity of hepatic stellate cells by hedgehog (Hh) pathway. We also assessed the markers of inflammatory response and endoplasmic reticulum (ER) stress. Male Albino rats were treated with either CCl4 (0.4 mg/kg twice/week) and/or Empa (10 mg/kg/day) for eight weeks. In this study, CCl4 rats had active Hh signaling as indicated by overexpression of Patched 1, Smoothened and Glioblastoma-2. CCl4 induced ER stress as CHOP expression was upregulated and ERAD was downregulated. CCl4-induced inflammatory response was demonstrated through increased levels of TNF-α, IL-6 and mRNA levels of IL-17 while undetectable expression of IL-10. Conversely, Empa elicited immunosuppression, suppressed the expression of Hh markers, and reversed markers of ER stress. In conclusion, Empa suppressed CCl4-induced Hh signaling and proinflammatory response, meanwhile embraced ER stress in the hepatic tissues, altogether provided hepatoprotection.


Subject(s)
Hedgehog Proteins , Liver Neoplasms , Rats , Male , Animals , Hedgehog Proteins/metabolism , Liver Cirrhosis/pathology , Liver/metabolism , Hepatic Stellate Cells/metabolism , Liver Neoplasms/pathology , Carbon Tetrachloride/adverse effects
3.
Neurology ; 101(15): 676-681, 2023 10 10.
Article in English | MEDLINE | ID: mdl-37527942

ABSTRACT

A 24-year-old Middle Eastern woman presented with a 2-month history of rapidly progressive asymmetric weakness and paresthesia that began in her left lower extremity and progressed to involve both legs and arms. It was associated with overflow urinary incontinence and significant weight loss. In addition, she complained of a constant occipital headache that worsened in the supine position and was associated with photophobia, tinnitus, nausea, vomiting, and horizontal binocular diplopia. She also had signs of meningismus, decreased left facial sensation, and right sensorineural hearing loss. Because multifocal localization suggests a wide variety of possible differential diagnoses, this study expands on the differential of a subacute multifocal process while highlighting the importance of identifying appropriate risk factors and performing a relevant yet focused diagnostic workup.


Subject(s)
Headache , Paresthesia , Humans , Female , Young Adult , Adult , Paresthesia/etiology , Headache/etiology , Clinical Reasoning
4.
Biochimie ; 207: 137-152, 2023 Apr.
Article in English | MEDLINE | ID: mdl-36351496

ABSTRACT

The established correlation between obesity and cognitive impairment portrays pharmacological products aimed at both disorders as an important therapeutic advance. Modulation of dysregulated adipokines and neurotransmitters is hence a critical aspect of the assessment of in-use drugs. At the cellular level, repairments in brain barrier integrity and cognitive flexibility are the main checkpoints. The aim of this study was to investigate whether melatonin and histidine, alone or in combination, could produce weight loss, meanwhile improve the cognitive processes. In this study, obese rat model was established by feeding high fat diet (HFD) composed of 25% fats (soybean oil) for 8 weeks, accompanied by melatonin (10 mg/kg), histidine (780 mg/kg), and combination of both in conventional form and nanoform. At the end of the study, adiposity hormones, neuronal monoamines and amino acids, brain derived neurotrophic factor (BDNF) and zonula occluden-1 (ZO-1) were assessed. HFD feeding resulted in significant weight gain and poor performance on cognitive test. Coadministration of histidine in the nanoform increased the level of ZO-1; an indicator of improving the brain barrier integrity, along with adjusting the adipokines and neurotransmitters levels, which had a positive impact on learning tasks. Cotreatment with melatonin resulted in an increase in the level of BDNF, marking ameliorated synaptic anomalies and learning disabilities, while reducing weight gain. On the other hand, the combination of melatonin and histidine reinstated the synaptic plasticity as well as brain barrier junctions, as demonstrated by increased levels of BDNF and ZO-1, positively affecting weight loss and the intellectual function.


Subject(s)
Diet, High-Fat , Melatonin , Rats , Animals , Melatonin/pharmacology , Melatonin/therapeutic use , Histidine/pharmacology , Histidine/therapeutic use , Brain-Derived Neurotrophic Factor/metabolism , Adipokines , Obesity/metabolism , Weight Gain , Cognition , Weight Loss
5.
Cureus ; 14(10): e29979, 2022 Oct.
Article in English | MEDLINE | ID: mdl-36381726

ABSTRACT

Incidentalomas are asymptomatic adrenal tumors that are discovered on investigations performed for other reasons. Classically, these tumors are found on computed tomography of the abdomen. This article describes an incidentaloma that was discovered on upper gastrointestinal endoscopy performed before a bariatric operation and caused an extrinsic compression of the first and second parts of the duodenum. Further investigations showed a 15-cm non-functional adrenal tumor. The patient was treated successfully with laparoscopic adrenalectomy. The histological examination showed a benign adrenocortical adenoma with myelolipomatous changes. The article highlights the fact that incidentalomas may not only be discovered on imaging modalities but may also show up in other diagnostic methods such as endoscopy.

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