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Oxidative Stress Is Associated with Neuroinflammation in Animal Models of HIV-1 Tat Neurotoxicity

Author(s):Jean-Pierre Louboutin -- Lokesh Agrawal -- Beverly A. S. Reyes -- Elisabeth J. Van Bockstaele -- David S. Strayer
Journal: Antioxidants
Publisher:
Abstract
| Pages: 414-438
HIV-1 trans-acting protein Tat, an essential protein for viral replication, is a key mediator of neurotoxicity. If Tat oxidant injury and neurotoxicity have been described, consequent neuroinflammation is less understood. Rat caudate-putamens (CPs) were challenged with Tat, with or without prior rSV40-delivered superoxide dismutase or glutathione peroxidase. Tat injection caused oxidative stress. Administration of Tat in the CP induced an increase in numbers of Iba-1- and CD68-positive cells, as well as an infiltration of astrocytes. We also tested the effect of more protracted Tat exposure on neuroinflammation using an experimental model of chronic Tat exposure. SV(Tat): a recombinant SV40-derived gene transfer vector was inoculated into the rat CP, leading to chronic expression of Tat, oxidative stress, and ongoing apoptosis, mainly located in neurons. Intra-CP SV(Tat) injection induced an increase in microglia and astrocytes, suggesting that protracted Tat production increased neuroinflammation. SV(SOD1) or SV(GPx1) significantly reduced neuroinflammation following Tat administration into the CP. Thus, Tat-induced oxidative stress, CNS injury, neuron loss and inflammation may be mitigated by antioxidant gene delivery.

Avocado Seeds: Extraction Optimization and Possible Use as Antioxidant in Food

Author(s):Francisco Segovia Gómez -- Sara Peiró Sánchez -- Maria Gabriela Gallego Iradi -- Nurul Aini Mohd Azman -- María Pilar Almajano
Journal: Antioxidants
Publisher:
Abstract
| Pages: 439-454
Consumption of avocado (Persea americana Mill) has increased worldwide in recent years. Part of this food (skin and seed) is lost during processing. However, a high proportion of bioactive substances, such as polyphenols, remain in this residue. The primary objective of this study was to model the extraction of polyphenols from the avocado pits. In addition, a further objective was to use the extract obtained to evaluate the protective power against oxidation in food systems, as for instance oil in water emulsions and meat products. Moreover, the possible synergy between the extracts and egg albumin in the emulsions is discussed. In Response Surface Method (RSM), the variables used are: temperature, time and ethanol concentration. The results are the total polyphenols content (TPC) and the antiradical power measured by Oxygen Radical Antioxidant Capacity (ORAC). In emulsions, the primary oxidation, by Peroxide Value and in fat meat the secondary oxidation, by TBARS (Thiobarbituric acid reactive substances), were analyzed. The RSM model has an R2 of 94.69 for TPC and 96.7 for ORAC. In emulsions, the inhibition of the oxidation is about 30% for pure extracts and 60% for the combination of extracts with egg albumin. In the meat burger oxidation, the formation of TBARS is avoided by 90%.

Screening of Antioxidant Activity of Gentian Lutea Root and Its Application in Oil-in-Water Emulsions

Author(s):Nurul Aini Mohd Azman -- Francisco Segovia -- Xavier Martínez-Farré -- Emilio Gil -- María Pilar Almajano
Journal: Antioxidants
Publisher:
Abstract
| Pages: 455-471
Gentiana Lutea root (G. Lutea) is a medicinal herb, traditionally used as a bitter tonic in gastrointestinal ailments for improving the digestive system. The active principles of G. Lutea were found to be secoiridoid bitter compounds as well as many other active compounds causing the pharmacological effects. No study to date has yet determined the potential of G. Lutea antioxidant activity on lipid oxidation. Thus, the aim of this study was to evaluate the effects of an extract of G. Lutea on lipid oxidation during storage of an emulsion. G. Lutea extracts showed excellent antioxidant activity measured by DPPH scavenging assay and Trolox equivalent antioxidant capacity (TEAC) assays. An amount of 0.5% w/w G. Lutea lyophilise was able to inhibit lipid oxidation throughout storage (p < 0.05). A mixture of G. Lutea with 0.1% (w/w) BSA showed a good synergic effect and better antioxidant activity in the emulsion. Quantitative results of HPLC showed that G.Lutea contained secoiridoid-glycosides (gentiopiocroside and sweroside) and post column analysis displayed radical scavenging activity of G. Lutea extract towards the ABTS radical. The results from this study highlight the potential of G. Lutea as a food ingredient in the design of healthier food commodities.

Oral Health Condition of Children Living with HIV

Author(s):Natália Spillere Rovaris -- Luiz Gustavo Teixeira Martins -- Jefferson Traebert
Journal: Dentistry Journal
Publisher:
Abstract
| Pages: 1-10
AIDS progression is faster in children than adults. Little is known about the oral health status of children living with HIV. Aim: To carry out a literature review about the oral health conditions of children living with HIV in order to observe if this specific population presents different oral health conditions compared to children without HIV infection. Methods: A documental study of literature review was carried out. Studies were searched at PubMed using “oral health”, “children”, “HIV” and “AIDS” as keywords. Papers published between 2001 and 2011 were included. After applying the exclusion criteria and complete reading of the selected studies, other articles were selected from the references lists of the first ones. Results: Firstly, 24 studies were identified. Among them, 65.5% were excluded according to the exclusion criteria. From the five selected articles, another five from the references of these were included. Only one article compared the oral health conditions of children living with HIV with controls without HIV infection. Conclusions: Only 10 papers contained information on the oral health conditions of children living with HIV, and just one compared the results with controls. The few studies found were insufficient to establish the oral health condition profile of children living with HIV. This lack of information could represent the lack of interest of researchers and health authorities in more integrative care and can result in neglect with this specific population of children.

Ridge Preservation with Modified “Socket-Shield” Technique: A Methodological Case Series

Author(s):Markus Glocker -- Thomas Attin -- Patrick R. Schmidlin
Journal: Dentistry Journal
Publisher:
Abstract
| Pages: 11-21
After tooth extraction, the alveolar bone undergoes a remodeling process, which leads to horizontal and vertical bone loss. These resorption processes complicate dental rehabilitation, particularly in connection with implants. Various methods of guided bone regeneration (GBR) have been described to retain the original dimension of the bone after extraction. Most procedures use filler materials and membranes to support the buccal plate and soft tissue, to stabilize the coagulum and to prevent epithelial ingrowth. It has also been suggested that resorption of the buccal bundle bone can be avoided by leaving a buccal root segment (socket shield technique) in place, because the biological integrity of the buccal periodontium (bundle bone) remains untouched. This method has also been described in connection with immediate implant placement. The present case report describes three consecutive cases in which a modified method was applied as part of a delayed implantation. The latter was carried out after six months, and during re-entry the new bone formation in the alveolar bone and the residual ridge was clinically evaluated as proof of principle. It was demonstrated that the bone was clinically preserved with this method. Possibilities and limitations are discussed and directions for future research are disclosed.

Improving Oral Health Status of Children in Tabuk, Saudi Arabia

Author(s):Ziad D. Baghdadi
Journal: Dentistry Journal
Publisher:
Abstract
| Pages: 22-40
This comprehensive community health intervention aimed to improve the oral health and reduce the incidence of dental caries in Tabuk schoolchildren. The program supports the public health pyramid that provides a framework to improve health and included creating and evaluating a school oral health surveillance system, applying fluoride varnish and dental sealants on high- and medium-caries risk children, and providing treatment for existing diseases. In a pilot phase, 48 children (26 males 22 females; mean age 6.42; dmft 9.33, Decayed, Missing, or Filled Primary and Permanent Teeth (DMFT) 3.27) received the dental services, both treatment and prevention. Three hundred seventy-eight composite resin or resin-modified light-cured glass ionomer restorations were placed. One-hundred and eighteen teeth received pulp therapy (pulpotomy or pulpectomy), ten of which received stainless steel crowns. A total of 72 teeth were extracted due to caries. To understand the effects of dental disease on children, as perceived by parents, an oral health-related quality of life survey was completed and analyzed. Results found an underestimation of the role the teeth play, particularly primary teeth, in the general health and wellbeing of the child. The program’s main evaluation effort focused on the process and outcome objectives, including the number of children received care, number of teeth received restorations and sealants, and number of children received fluoride varnish, etc. Analyzing the effect of the program on oral hygiene revealed an improvement in oral health, as a direct result of oral health educational sessions and one-to-one counseling. There is an urgent need to expand the program to include all primary schools.

Comprehensive Implementation of the International Caries Detection and Assessment System (ICDAS) in a Dental School and University Oral Health Centre: A Stepwise Framework

Author(s):Priya Ahlawat -- Abhishek Parolia -- Zeinab Hasan -- Frederick C. Smales -- Allan Pau -- Chooigait G. Toh
Journal: Dentistry Journal
Publisher:
Abstract
| Pages: 41-51
ICDAS (the International Caries Detection and Assessment System) is a new approach to the detection and classification of dental caries, starting with the stage showing the earliest visual changes. Methodology: This article describes the implementation of the ICDAS at the School of Dentistry, International Medical University, and Kuala Lumpur, Malaysia in a step-by-step systematically planned process. Beginning with the setting up of a Task Force in 2011 for the evaluation and preparation of the training resources and the running of exploratory training exercises, it finally culminated in carrying out training workshops for the entire staff and students. After the internal processes had been completed, an international expert (KE) was invited to evaluate the process and conduct another workshop using the resources developed within the University, including a reference set of carious teeth. The overall time taken was one and a half years. Conclusions: The implementation of the ICDAS has been comprehensively set into motion within the context of our local curriculum and oral healthcare delivery arrangements. However, this will be an ongoing process with further quality assurance measures being required clinically together with the continuing training of new staff. Sharing this ‘framework’ of the ICDAS implementation process should considerably ease the path and reduce the time period of future implementations by other dental teaching institutions.

An Improved Neutral a-Glucosidase Assay for Assessment of Epididymal Function—Validation and Comparison to the WHO Method

Author(s):Frank Eertmans -- Veerle Bogaert -- Tanita Van Poecke -- Barbara Puype
Journal: Diagnostics
Publisher:
Abstract
| Pages: 1-11
Neutral a-glucosidase (NAG) activity in human seminal plasma is an important indicator for epididymis functionality. In the present study, the classic World Health Organization (WHO) method has been adapted to enhance assay robustness. Changes include modified enzyme reaction buffer composition and usage of an alternative enzyme inhibitor for background correction (glucose instead of castanospermine). Both methods have been tested in parallel on 144 semen samples, obtained from 94 patients/donors and 50 vasectomized men (negative control), respectively. Passing-Bablok regression analysis demonstrated equal assay performance. In terms of assay validation, analytical specificity, detection limit, measuring range, precision, and cut-off values have been calculated. These data confirm that the adapted method is a reliable, improved tool for NAG analysis in human semen.

Acknowledgement to Reviewers of Diagnostics in 2013

Author(s):Diagnostics Editorial Office
Journal: Diagnostics
Publisher:
Abstract
| Pages: 12-12
The editors of Diagnostics would like to express their sincere gratitude to the following reviewers for assessing manuscripts in 2013. [...]
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