Production of Dense Cu-10Sn Part by Laser Powder Bed Fusion with Low Surface Roughness and High Dimensional Accuracy

Tin-bronze alloys with a tin content of at least 10 wt% have excellent mechanical properties, wear resistance, and corrosion resistance. Among these alloys, Cu-10Sn was investigated in this study for production with the laser powder bed fusion process with a 500W Yb:YAG laser. In particular, a design of experiment (DoE) was developed in order to identify the optimal process parameters to obtain full density, low surface roughness, and high dimensional accuracy. Samples were characterized with Archimedes’ method and optical microscopy to determine their final density. It was shown that the first method is fast but not as reliable as the second one. A first mechanical characterization was performed through microhardness tests. Finally, a set of process parameters was identified to produce fully dense samples with low surface roughness and high accuracy. The results showed that the volumetric energy density could represent an approach that is too simplified, therefore limiting the direct correlation with the physical aspects of the process.     

An unusual case of postaxial polydactyly of the feet

Polydactyly is a fairly common congenital anomaly characterized by additional fingers and/or toes, generally divided into three groups: medial ray (preaxial) and central and lateral ray (postaxial). We present a case of postaxial (fibular) polydactyly of the feet, assaying its clinical and radiological features and the method of surgical correction. Clinical outcomes after initial surgery were excellent in both feet. This surgical case shows that a careful individual preoperative planning is necessary to achieve good functional and cosmetic outcome. Level of Evidence: Level V, therapeutic study.     

Prevalence of Thoracic Aortic Aneurysms in Patients with Degenerative Abdominal Aortic Aneurysms: Results from the Prospective ACTA Study

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Role of Bowel Ultrasound in the Diagnosis and Follow-up of Patients with Crohn's Disease

Crohn's disease (CD) is an inflammatory chronic bowel disorder; it can involve the whole gastrointestinal tract, but its localization in the ileum or colon is most common. The reference standard for the diagnosis of CD is ileocolonoscopy with histologic assessment. The reference standard for the detection of any complications is surgery. However, imaging techniques have an important role both in the detection/localization of CD and in the follow-up of CD patients. In the last few years, the technical development of ultrasound equipment, the advent of new technologies such as elastography and mostly the increased expertise of sonographers have boosted the role of bowel ultrasound in assessment of the gastrointestinal tract. In fact, bowel ultrasound is particularly attractive thanks to its widespread availability, non-invasiveness, low cost and good reproducibility, as it can be easily repeated during follow-up. The aim of this article is to provide an extensive overview of the actual role of bowel ultrasound in the detection and follow-up of patients with CD.     

Melatonin modulates neonatal brain inflammation through endoplasmic reticulum stress,autophagy, and miR‐34a/silent information regulator 1 pathway

Maternal infection/inflammation represents one of the most important factors involved in the etiology of brain injury in newborns. We investigated the modulating effect of prenatal melatonin on the neonatal brain inflammation process resulting from maternal intraperitoneal (i.p.) lipopolysaccharide (LPS) injections. LPS (300 μg/kg) was administered to pregnant rats at gestational days 19 and 20. Melatonin (5 mg/kg) was administered i.p. at the same time as LPS. Melatonin counteracted the LPS sensitization to a second ibotenate‐induced excitotoxic insult performed on postnatal day (PND) 4. As melatonin succeeded in reducing microglial activation in neonatal brain at PND1, pathways previously implicated in brain inflammation regulation, such as endoplasmic reticulum (ER) stress, autophagy and silent information regulator 1 (SIRT1), a melatonin target, were assessed at the same time‐point in our experimental groups. Results showed that maternal LPS administrations resulted in an increase in CHOP and Hsp70 protein expression and eIF2α phosphorylation, indicative of activation of the unfolded protein response consequent to ER stress, and a slighter decrease in the autophagy process, determined by reduced lipidated LC3 and increased p62 expression. LPS‐induced inflammation also reduced brain SIRT1 expression and affected the expression of miR‐34a, miR146a, and miR‐126. All these effects were blocked by melatonin. Cleaved‐caspase‐3 apoptosis pathway did not seem to be implicated in the noxious effect of LPS on the PND1 brain. We conclude that melatonin is effective in reducing maternal LPS‐induced neonatal inflammation and related brain injury. Its role as a prophylactic/therapeutic drug deserves to be investigated by clinical studies.     

FATAL OUTCOME OF INFECTION BY DENGUE 4 IN A PATIENT WITH THROMBOCYTOPENIC PURPURA AS A COMORBID CONDITION IN BRAZIL

Dengue is currently a major public-health problem. Dengue virus (DENV) is classified into four distinct serotypes, DENV 1-4. After 28 years of absence, DENV-4 was again detected in Brazil in 2010 in Roraima State, and one year later, the virus was identified in the northern Brazilian states of Amazonas and Pará, followed by Rio de Janeiro and São Paulo. In Minas Gerais, the first confirmed case of DENV-4 occurred in the municipality of Frutal in 2011 and has now been isolated from a growing number of patients. Although DENV-2 is associated with the highest risk of severe forms of the disease and death due to the infection, DENV-4 has also been associated with severe forms of the disease and an increasing risk of hemorrhagic manifestations. Herein, the first fatal case of confirmed DENV-4 in Brazil is reported. The patient was an 11-year-old girl from the municipality of Montes Claros in northern Minas Gerais State, Brazil. She had idiopathic thrombocytopenic purpura as a comorbid condition and presented with a fulminant course of infection, leading to death due to hemorrhagic complications. Diagnosis was confirmed by detection of Dengue-specific antibodies using IgM capture enzyme-linked immunosorbent assay and semi-nested RT-PCR. Primary care physicians and other health-care providers should bear in mind that DENV-4 can also result in severe forms of the disease and lead to hemorrhagic complications and death, mainly when dengue infection is associated with coexisting conditions.     

Effects of tramadol on viscero‐visceral hyperalgesia in a rat model of endometriosis plus ureteral calculosis

The effects of tramadol versus placebo administration on behavioral indicators of ureteral pain, pelvic pain and referred lumbar muscle hyperalgesia were investigated in a rat model of viscero‐visceral hyperalgesia from endometriosis plus ureteral calculosis (endo + stone). Fifty female Sprague‐Dawley rats underwent surgical induction of endometriosis and, 2 weeks later, were randomly assigned to five groups (10 each), to be treated i.p., twice a day, with tramadol (0.625, 1.25, 2.5, or 5 mg/kg) or saline for 5 days (14–18th day postendometriosis; prestone treatment). On the 21st day, they underwent laparotomy for stone formation in the upper left ureter (dental cement injection). All were video‐taped 24 h nonstop for 7 days before and 4 days after stone formation (14–25th day postendometriosis) to record ureteral and pelvic pain behaviors. Lumbar sensitivity (L1) was tested bilaterally, daily over the same period, by verifying presence/absence of vocalization upon muscle pinching at a predefined pressure (calibrated forceps). Additional fifty endo + stone rats underwent the same protocol, except that treatment was performed on 21st–25th day (poststone treatment). Tramadol vs. saline significantly reduced number and duration of ureteral crises, duration of pelvic behavior, and incidence of muscle hyperalgesia (P < 0.0001), with a dose‐dependent effect. Prestone treatment was significantly more effective than poststone treatment for the 1.25 dose for all parameters and 2.5 dose for pelvic and muscle parameters (0.003 > P < 0.02). Tramadol, even at low doses, is thus highly protective against pain from ‘viscero‐visceral hyperalgesia’ in endometriosis plus ureteral calculosis; it can represent a valid therapeutic approach in women with these comorbidities.     

Diesel exhaust particulates affect cell signaling,mucin profiles,and apoptosis in trachea explants of Balb/C mice

Particulate matter from diesel exhaust (DEP) has toxic properties and can activate intracellular signaling pathways and induce metabolic changes. This study was conducted to evaluate the activation of extracellular signal‐regulated kinase (ERK) and c‐Jun N‐terminal kinase (JNK) and to analyze the mucin profile (acid (AB⁺), neutral (PAS⁺), or mixed (AB/PAS⁺) mucus) and vacuolization (V) of tracheal explants after treatment with 50 or 100 μg/mL DEP for 30 or 60 min. Western blot analyses showed small increases in ERK1/2 and JNK phosphorylation after 30 min of 100 μg/mL DEP treatment compared with the control. An increase in JNK phosphorylation was observed after 60 min of treatment with 50 μg/mL DEP compared with the control. We did not observe any change in the level of ERK1/2 phosphorylation after treatment with 50 μg/mL DEP. Other groups of tracheas were subjected to histological sectioning and stained with periodic acid‐Schiff (PAS) reagent and Alcian Blue (AB). The stained tissue sections were then subjected to morphometric analysis. The results obtained were compared using ANOVA. Treatment with 50 μg/mL DEP for 30 min or 60 min showed a significant increase (p < 0.001) in the amount of acid mucus, a reduction in neutral mucus, a significant reduction in mixed mucus, and greater vacuolization. Our results suggest that compounds found in DEPs are able to activate acid mucus production and enhance vacuolization and cell signaling pathways, which can lead to airway diseases. © 2014 Wiley Periodicals, Inc. Environ Toxicol 30: 1297–1308, 2015.