Cell culture is widely used by biochemists and cell/molecular biologists, but the fluctuating (and often elevated) levels of O ₂ to which cells in culture are exposed can affect many of their properties. So can the low level of antioxidants found in some cell culture media. Reagents, especially "antioxidants," added to cell culture media can react with the constituents of the media to produce H ₂ O ₂ and degradation products that can influence cell behavior. Several published papers describing the cellular effects of ascorbate, polyphenols, and carotenoids have, in fact, reported artifacts due to the actions of the degradation products of these "antioxidants." A greater awareness of the potential artifacts in cell culture studies is needed among the free radical/antioxidant community.

The radical scavenging antioxidants play an essential role in the maintenance of health and prevention of diseases, and a thorough understanding of the action and capacity of antioxidants is critically important. Despite the assumption that antioxidants must exert beneficial effects against oxidative stress, many large-scale randomized controlled trials gave inconsistent and disappointing results on the prevention of chronic diseases. It is now generally accepted that there is no evidence to support the use of non-discriminative antioxidant supplements for prevention of diseases. On the other hand, recent data show that antioxidants may be effective in the prevention and/or treatment of diseases when the right antioxidant is given to the right subject at the right time for the right duration. Now it is accepted that reactive oxygen species (ROS) act as physiologically important signaling messengers as well as deleterious agents. The signaling ROS are produced in a subtly regulated manner, while many deleterious ROS are produced and react randomly. Free radical-mediated lipid peroxidation products which, in contrast to enzymatic oxidation products, are produced by non-specific mechanisms cause oxidative damage, but may also induce adaptive response to enhance the expression of antioxidant enzymes and compounds. This has raised a question if removal of too many ROS by supplementation of antioxidants may upset the cell signaling pathways and actually increase the risk of chronic diseases. However, it is unlikely that antioxidants impair physiologically essential signaling pathways.

The ω-3 and ω-6 polyunsaturated fatty acids (PUFAs) are two major families of PUFAs present as essential cellular components which possess diverse bioactivities. The ω-3s, mainly found in seafood, are associated with many beneficial effects on human health, while the ω-6s are more abundant in our daily diet and could be implicated in many pathological processes including cancer development. Increasing evidence suggests that the adverse effects of ω-6s may be largely attributed to arachidonic acid (AA, a downstream ω-6) and the metabolite prostaglandin E2 (PGE2) that stems from its cyclooxygenase (COX)-catalyzed lipid peroxidation. On the other hand, two of AA's upstream ω-6s, γ-linolenic acid (GLA) and dihomo-γ-linolenic acid (DGLA), are shown to possess certain anti-cancer activities, including inducing cell apoptosis and inhibiting cell proliferation. In this paper, we review the documented anti-cancer activities of ω-6 PUFAs, including the recent findings regarding the anti-cancer effects of free radical-mediated DGLA peroxidation. The possible mechanisms and applications of DGLA (and other ω-6s) in inducing anti-cancer activity are also discussed. Considering the wide availability of ω-6s in our daily diet, the study of the potential beneficial effect of ω-6 PUFAs may guide us to develop an ω-6-based diet care strategy for cancer prevention and treatment.

Peroxynitrite, a representative of reactive nitrogen species, plays important roles in the physiological and pathological processes of many oxidative stress-related diseases. It is generated from the reaction of nitric oxide (NO) and superoxide (O2^·–) and is far more active than its precursors. Peroxynitrite can be further decomposed into other cytotoxic reactive species. Peroxynitrite and its derivatives can interact with various biomolecules such as DNA and proteins. Due to its high reactivity and short lifetime, accurate detection of peroxynitrite in biological systems is a challenge task. In the last decade, huge efforts have been made to develop reliable techniques to assess the generation of peroxynitrite in various cellular and animal experiments. There are three major approaches for peroxynitrite detection, including electrochemical sensors, detection of nitrotyrosine formation, and fluorescent probes. Particularly, progress has been made in developing novel fluorescent probes to detect peroxynitrite with relatively high sensitivity and specificity. Herein, we review the recent progress made in peroxynitrite detection methods and discuss the advantages and disadvantages of these methods. The development of these techniques will offer new opportunities for understanding the roles of peroxynitrite in the oxidative stress-related physiological and pathological conditions and provide platforms for drug discovery targeting peroxynitrite and other free radicals for therapeutic purposes.

Background: Haplotype structure of the microtubule-associated protein tau (MAPT) gene is associated with various tauopathies in the Caucasian population. With the knowledge that the association between MAPT structure and disease may be distinct in different ethnics, we intend to investigate the haplotype structure of MAPT in Taiwanese and test it for association with Alzheimer's disease (AD). Methods: One hundred and eight AD patients and 108 sex- and-age matched healthy controls were recruited from the dementia outpatient clinic of Chang Gung Medical center. We genotyped the del-In9 marker that defines the extended H1 and H2 clades. We selected 21 single-nucleotide polymorphisms (SNPs) in the extended MAPT region from Japanese SNPs database and dbSNP database. Using the software TagIt, we analyzed the linkage disequilibrium structure of MAPT and compared the allele and genotype distribution between patient group and control group. Results: All the Taiwanese participants were H1 haplotypes. Linkage disequilibrium analysis showed the haplotype blocks in Taiwanese population had a smaller size in comparison to that of the Caucasian population. Single locus association showed significant p value in one of the tagging variants (rs242557) in our Taiwanese AD case-control cohorts. Conclusion: MAPT gene has four haplotype blocks in the Taiwanese population, each of around 40 kbp. In both European study and our study, the SNP rs242557 showed association with AD. Given the position of this SNP, the most possible explanation is that genetic variability in tau expression contributes to the risk of developing AD.

Background: To evaluate the efficacy and adverse events of cisplatin, tegafur, and leucovorin concomitantly with radiotherapy for patients with advanced, non-metastatic squamous cell carcinoma (SCC) of the oropharynx and hypopharynx. Methods: The PTL regimen consisted of cisplatin (P) 50 mg/m ² on day 1, oral tegafur (T) 800 mg/day plus leucovorin (LV) 60 mg/day on days 1 through 14. It was repeated every 2 weeks through the radiotherapy course. Conventional radiotherapy with 1.8-2.0 Gy/day, 5 days per week, was delivered in a total dose of between 70 and 72 Gy. Results: Sixty-five patients with stage III or IV of SCC of the head and neck were consecutively treated between May 2002 and November 2005. Forty-six (70.7%) patients had complete response after concomitant chemoradiotherapy (CCRT). With a median follow-up of 54.0 months (range 1-103 months), the 5-year locoregional control, progression-free survival, and overall survival rates were 50.6%, 40.7%, and 59.7%, respectively. Three (4.6%) patients had toxic death during treatment. Fifty-one (80.0%) patients experienced grade 3-4 mucositis which occurred in about 35% of the CCRT duration. The functional preservation rate among post-CCRT complete responders was 93.5% (43/46). The median cisplatin accumulated dosage was 150 mg, and the rate of hearing impairment among the survivors was 7.8%. Conclusion: CCRT with outpatient-based PTL for advanced SCC of oropharynx and hypopharynx is feasible and has comparative efficacy and acceptable adverse events.

Background: We modified 3-week XELOX regimen with oxaliplatin to 85 mg/m ² on Day 1 and capecitabine 1000 mg/m ² BID for 10 days every 14 days to be more practical in clinical practice for advanced gastric cancer. The aim of this retrospective analysis is to evaluate the safety profile and efficacy of the modified oxaliplatin plus capecitabine (XELOX) regimen as the first-line treatment for patients with advanced gastric cancer in a medical center in Taiwan. Methods: From March 2009 to December 2010, among the 614 patients diagnosed with gastric cancer in a medical center, 49 patients with unresectable advanced or metastatic gastric adenocarcinoma were treated with oxaliplatin (85 mg/m ² ) on Day 1 and capecitabine (1000 mg/m ² BID) for 10 days every 2 weeks (mXELOX). CT scan was performed for tumor response evaluation. Clinical outcome and adverse events after mXELOX treatment were analyzed retrospectively. Results: A total of 354 mXELOX sessions (median: 6) were administered in 49 patients. The overall tumor response rate was 39.1% among 46 evaluated patients: three complete response (6.5%) and 15 partial response (32.6%). Seven patients had stable disease (15.2%) and 21 (45.7%) patients had progressive disease. The median progression-free survival and median overall survival were 4.37 months and 12.26 months, respectively. The most common grade III/IV hematologic toxicity was anemia (10.2%), and non-hematologic toxicity effects were numbness (8.2%), hand-foot syndrome (10.2%), diarrhea (6.1%), thrombocytopenia (6.1%), and abdominal pain (6.1%). Conclusion: This modified biweekly oxaliplatin and capecitabine combination chemotherapy is practical and effective for unresectable advanced or metastatic gastric cancer in our daily practice.

Background: Pain control has been emphasized as a priority for both practitioners and inpatients with rib fractures, since analgesia could only offer limited relief from severe pain. A prospective and randomized controlled trial was conducted to analyze the efficacy and efficiency of acupuncture in acute pain relief for inpatients with rib fractures. Methods: A total of 58 inpatients were recruited and allocated to two groups, receiving identical doses of conventional oral analgesics as well as filiform needles as treatment and thumbtack intradermal (TI) needles placed upon the skin surface as a control, respectively, via novel acupuncture modality once daily for three consecutive days. The effect of pain relief was evaluated during activities that induce pain, and sustained maximal inspiration (SMI) lung volumes and sleep quality were assessed. Results: The patients treated with filiform needles had more effective pain relief than those in the TI needle group during deep breathing, coughing, and turning over the body (p < 0.05), and the effect persisted for at least 6 h in most patients. Sustained maximal inspiration lung volumes and sleep quality did not show improvement through every acupuncture intervention, and they could not respond accurately to pain relief via acupuncture. Conclusion: The active evaluation could provide a more adaptive model for assessing pain intensity due to rib fractures. This novel acupuncture modality in which the needle insertion sites are corresponding to the pain spots can be a safe and viable therapy for relieving pain in inpatients with rib fractures.

Background: The purpose of this study was to compare patients' subjective experiences with respect to long-term satisfaction with mandibular implant-retained overdentures versus conventional complete dentures. Methods: Among 85 completely edentulous patients, 60 were treated with four one-stage titanium implants and overdentures retained by a cast bar with extracoronal attachments. These patients constituted the experimental group, and were subsequently evaluated clinically over a period of up to 6 years. The other 25 patients constituted the control group and were treated with conventional complete dentures without implant retained. All the patients (n = 60) in the experimental group responded to questions on their experiences before and after treatment with the implant-retained overdentures. Sixty percent (n = 15) of the 25 patients in the control group responded to the questionnaire. Results: No implants or restorations failed during the observation period. The experimental group, however, showed significant differences with the control group in terms of their responses to the questionnaire. Conclusion: The use of implants to retain and support the overdenture improved comfort and gave the experimental patients greater self-confidence in social interactions, in addition to more effective oral rehabilitation. The results demonstrate that the effects of rehabilitation of the mandibular arch with an implant-retained overdenture are predictable.

The number of proteins produced by the 30,000-40,000 genes of the human genome is estimated to be three or four orders of magnitude higher. Proteomics is a rapidly developing science. In principle, two main areas in the field of proteomics have been developed, each of them having its pros and cons. These fields are profiling and functional proteomics. The aim of the proteomic profiling is to describe and index the whole set of proteins of a biological sample, which could be an organism, an organ, or a cell, or parts there of like individual's tissue or organelles. In our understanding, both types of proteomics (profiling and functional) are valuable tools complementing other biological methodologies.