scholarly journals Intraoral Laser Welding (ILW) in Implant Prosthetic Dentistry: Case Report

2012 ◽  
Vol 2012 ◽  
pp. 1-4 ◽  
Author(s):  
Carlo Fornaini ◽  
Elisabetta Merigo ◽  
Igor Cernavin ◽  
Gonzalo Lòpez de Castro ◽  
Paolo Vescovi
Keyword(s):  
Clinical Study ◽  
Laser Welding ◽  
Nd:Yag Laser ◽  
Human Subjects ◽  
Welding Process ◽  
Weld Metals ◽  
Dental Offices ◽  
Metal Welding

The aim of this clinical study was to describe the possibility of using the Nd:YAG laser device utilized in the dental offices to weld metals intraorally. The authors, before applying this technique “in vivo” on human subjects, tested the “in vitro” metal welding efficacy of dental Nd:YAG device firstly by interferometry, SEM, and EDS and subsequently by thermal camera and thermocouples in order to record temperature changes during the welding process on bovine jaws. Four implants were inserted in the edentulous maxillary arch of a 67 years old male patient. Immediately after that, a bar previously made by the dental technician was intraorally welded to the abutments by Nd:YAG laser (Fidelis Plus III, Fotona, Slovenia) with these parameters: 9.90 mJ, 1 Hz, 15 msec, 0.6 mm spot. Then the prosthesis was connected to the bar with four OT Caps. This clinical study, even if preliminary, suggests that laser welding technique may be intraorally used without side effects.

Clock gene-independent daily regulation of haemoglobin oxidation in red blood cells

2021 ◽  
Author(s):  
Andrew D. Beale ◽  
Priya Crosby ◽  
Utham K. Valekunja ◽  
Rachel S. Edgar ◽  
Johanna E. Chesham ◽  
...  
Keyword(s):  
Circadian Rhythms ◽  
Red Blood Cells ◽  
Blood Cells ◽  
Human Subjects ◽  
Developmental Regulation ◽  
Physiological Role ◽  
Cell Types ◽  
The Body

AbstractCellular circadian rhythms confer daily temporal organisation upon behaviour and physiology that is fundamental to human health and disease. Rhythms are present in red blood cells (RBCs), the most abundant cell type in the body. Being naturally anucleate, RBC circadian rhythms share key elements of post-translational, but not transcriptional, regulation with other cell types. The physiological function and developmental regulation of RBC circadian rhythms is poorly understood, however, partly due to the small number of appropriate techniques available. Here, we extend the RBC circadian toolkit with a novel biochemical assay for haemoglobin oxidation status, termed “Bloody Blotting”. Our approach relies on a redox-sensitive covalent haem-haemoglobin linkage that forms during cell lysis. Formation of this linkage exhibits daily rhythms in vitro, which are unaffected by mutations that affect the timing of circadian rhythms in nucleated cells. In vivo, haemoglobin oxidation rhythms demonstrate daily variation in the oxygen-carrying and nitrite reductase capacity of the blood, and are seen in human subjects under controlled laboratory conditions as well as in freely-behaving humans. These results extend our molecular understanding of RBC circadian rhythms and suggest they serve an important physiological role in gas transport.

Carbamazepine pharmacokinetics are not affected by zonisamide: in vitro mechanistic study and in vivo clinical study in epileptic patients

2004 ◽  
Vol 62 (1) ◽  
pp. 1-11 ◽  
Author(s):  
Isabelle Ragueneau-Majlessi ◽  
Rene H. Levy ◽  
Donna Bergen ◽  
William Garnett ◽  
William Rosenfeld ◽  
...  
Keyword(s):  
Clinical Study ◽  
Mechanistic Study ◽  
Epileptic Patients

Welding characteristics of S45C medium carbon steel in laser welding process using a high power CW Nd:YAG laser

2004 ◽  
Vol 39 (19) ◽  
pp. 6117-6119 ◽  
Author(s):  
Young-Tae Yoo ◽  
Dong-Gyu Ahn ◽  
Kung-Bo Ro ◽  
Seong-Wook Song ◽  
Ho-Jun Shin ◽  
...  
Keyword(s):  
Carbon Steel ◽  
Laser Welding ◽  
High Power ◽  
Nd:Yag Laser ◽  
Welding Process ◽  
Medium Carbon Steel ◽  
Medium Carbon ◽  
Laser Welding Process

scholarly journals Interfacial Characteristics of Dissimilar Ti6Al4V/AA6060 Lap Joint by Pulsed Nd:YAG Laser Welding

Metals ◽  
2019 ◽  
Vol 9 (1) ◽  
pp. 71 ◽  
Author(s):  
Xin Xue ◽  
António Pereira ◽  
Gabriela Vincze ◽  
Xinyong Wu ◽  
Juan Liao
Keyword(s):  
Laser Welding ◽  
Nd:Yag Laser ◽  
Laser Beam Welding ◽  
Welding Process ◽  
Mechanical Resistance ◽  
Lap Joint ◽  
Important Indicator ◽  
Pulsed Nd:Yag Laser ◽  
Pulsed Nd:Yag Laser Welding ◽  
Interfacial Characteristics

This paper focuses on the interfacial characteristics of dissimilar Ti6Al4V/AA6060 lap joint produced by pulsed Nd:YAG laser beam welding. The process-sensitivity analysis of welding-induced interface joining quality was performed by using the orthogonal design method. Microstructural tests such as scanning electron microscopy and energy dispersive X-ray spectroscopy were used to observe the interfacial characteristics. The mechanism of interfacial crack initiation, which is an important indicator of joint property and performance, was assessed and analyzed. The preferred propagation paths of welding cracks along the interfaces of different intermetallic layers with high dislocation density were analyzed and discussed in-depth. The results indicate that discontinuous potential phases in the micro-crack tip would mitigate the mechanical resistance or performance of the welded joint, while the continuous intermetallic layer can lead to a sound jointing performance under pulsed Nd:YAG laser welding process.

scholarly journals Circulating vaspin and visfatin are not affected by acute or chronic energy deficiency or leptin administration in humans

2011 ◽  
Vol 164 (6) ◽  
pp. 911-917 ◽  
Author(s):  
Eun Seok Kang ◽  
Faidon Magkos ◽  
Elizabeth Sienkiewicz ◽  
Christos S Mantzoros
Keyword(s):  
Human Subjects ◽  
Normal Weight ◽  
Hypothalamic Amenorrhea ◽  
Energy Deficiency ◽  
Chronic Energy Deficiency ◽  
Before And After ◽  
Term Energy ◽  
Energy Deprivation

ObjectiveAnimal and in vitro studies indicate that leptin alleviates starvation-induced reduction in circulating vaspin and stimulates the production of visfatin. We thus examined whether vaspin and visfatin are affected by short- and long-term energy deprivation and leptin administration in human subjects in vivo.Design and methodsWe measured circulating levels of vaspin and visfatin i) before and after 72 h of starvation (leading to severe hypoleptinemia) with or without leptin administration in replacement doses in 13 normal-weight subjects, ii) before and after 72 h of starvation with leptin administration in pharmacological doses in 13 lean and obese subjects, iii) during chronic energy deficiency in eight women with hypothalamic amenorrhea on leptin replacement for 3 months, and iv) during chronic energy deficiency in 18 women with hypothalamic amenorrhea on leptin replacement or placebo for 3 months.ResultsAcute starvation decreased serum leptin to 21% of baseline values, (P=0.002) but had no significant effect on vaspin and visfatin concentrations (P>0.05). Nor did normalization of leptin levels affect the concentrations of these two adipokines (P>0.9). Leptin replacement in women with hypothalamic amenorrhea did not significantly alter vaspin and visfatin concentrations, whether relative to baseline or placebo administration (P>0.25). Pharmacological doses of leptin did not affect circulating vaspin and visfatin concentrations (P>0.9).ConclusionsCirculating vaspin and visfatin are not affected by acute or chronic energy deficiency leading to hypoleptinemia and are not regulated by leptin in human subjects, indicating that these adipocyte-secreted hormonal regulators of metabolism are independently regulated in humans.

scholarly journals Determination of activity of antioxidants in human subjects

1999 ◽  
Vol 58 (4) ◽  
pp. 1015-1024 ◽  
Author(s):  
Garry G. Duthie
Keyword(s):  
Oxidative Stress ◽  
Human Subjects ◽  
Control Schemes ◽  
Total Antioxidant ◽  
Plasma Measurements ◽  
Determination Of Activity ◽  
Nutritional Antioxidants

Evidence from biochemical and animal models suggests that nutritional antioxidants should inhibit the development of diseases such as CHD and certain cancers. This evidence is not clearly corroborated by intervention studies in human subjects, due, in part, to inadequacies in current analytical methodologies. Althoughin vitroassays can give useful information on the attributes required by a compound to act as an antioxidant, results may have little nutritional relevance due to limited bioavailability. The determination of antioxidants in blood is often used as a measure of antioxidant statusin vivo, but may not necessarily reflect concentrations in target tissues where oxidative stress is greatest. In addition, the accumulation of antioxidants in selective tissues may not be apparent from plasma measurements. Participation in quality-control schemes for antioxidant determination by HPLC allows inter-laboratory comparison of results. Moderation of indices of oxidative damage to lipids, proteins and DNA can provide information on the effectiveness of compounds as nutritional antioxidants. However, most current methods of assessing oxidative stress are subject to confounding factors of non-oxidative origin. Assays for total antioxidant capacity in plasma differ in their type of oxidation source, target and measurement used to detect the oxidized product. They give different results, should never be used in isolation, and results should be interpreted with caution. Until more is known about the activity and metabolic fate of antioxidants, caution should be exercised in the consumption of large amounts of commercially-available antioxidant preparations.

scholarly journals Assessing Uncertainty in A2 Respiratory Syncytial Virus Viral Dynamics

2015 ◽  
Vol 2015 ◽  
pp. 1-9 ◽  
Author(s):  
Gilberto González-Parra ◽  
Hana M. Dobrovolny
Keyword(s):  
Respiratory Syncytial Virus ◽  
Human Subjects ◽  
Respiratory Illness ◽  
The United States ◽  
Viral Kinetics ◽  
Phase Duration ◽  
Syncytial Virus ◽  
Parameter Values

Respiratory syncytial virus (RSV) is the most common cause of bronchiolitis and pneumonia in children younger than 1 year of age in the United States. Moreover, RSV is being recognized more often as a significant cause of respiratory illness in older adults. Although RSV has been studied both clinically and in vitro, a quantitative understanding of the infection dynamics is still lacking. In this paper, we study the effect of uncertainty in the main parameters of a viral kinetics model of RSV. We first characterize the RSV replication cycle and extract parameter values by fitting the mathematical model to in vivo data from eight human subjects. We then use Monte Carlo numerical simulations to determine how uncertainty in the parameter values will affect model predictions. We find that uncertainty in the infection rate, eclipse phase duration, and infectious lifespan most affect the predicted dynamics of RSV. This study provides the first estimate of in vivo RSV infection parameters, helping to quantify RSV dynamics. Our assessment of the effect of uncertainty will help guide future experimental design to obtain more precise parameter values.

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