An Active Power Control Technique for Downlink Interference Management in a Two-Tier Macro⁻Femto Network.

The femtocell has evolved as a great solution for improving coverage and traffic offloading from the current LTE cellular networks, and it accomplishes the dreams of the high data rate for indoor mobile users. However, the exponentially expanding LTE femtocells cause interference in the network, as they share the same licensed spectrum with a macrocell. To tackle this issue, numerous interference mitigation techniques have been proposed in the literature. In this paper, we proposed an Active Power Control (APC) technique, which not only reduces Inter-Cell Interference (ICI) in a Macro User Equipment (MUE), generated from the downlink transmission power of an inadequately deployed femtocell, but also reduces unnecessary power consumption to achieve a green femtocell network. The simulation results show that the proposed APC technique effectively reduces ICI and optimizes the throughput performance of the MUE. Compared with the existing power control techniques, the APC technique provides a balanced trade-off in attaining necessary Quality-of-Service (QoS) of the Femto User Equipment (FUE) and reducing ICI to the victim MUE existing in the close proximity of the femtocell.

Diagnostic utility of glycosyltransferase mRNA expression in gastric cancer.

OBJECTIVE/BACKGROUND: Posttranslational modification of proteins, including glycosylation, is known to differ between normal and tumor cells. Altered glycosyltransferase levels have been observed in tumor tissues and their role in tumor metastasis and invasion has been implicated. In this study the role of altered glycosyltransferase messenger RNA (mRNA) levels in serum of gastric cancer patients as early markers of gastric cancer was evaluated. METHODS: In this case control study the expression profile of ppGalNAc-T6, GlcNAcT-V, ST3Gal I, ST3 Gal IV, and ST6GalNAc-I in normal healthy control and gastric cancer patients was compared. Serum was isolated from blood samples of gastric cancer patients (n = 200) and controls (n = 200). Following RNA extraction, reverse transcription was carried out and transcript levels of glycosyltransferases were determined using real-time quantitative polymerase chain reaction and normalized against glyceraldehyde-3-phosphate dehydrogenase (GAPDH) expression. The amount of target gene, normalized to an endogenous reference gene relative to calibrator was calculated by using ΔΔCT method. Transcript levels in the serum samples of gastric cancer patients were compared with those of controls; also the same was correlated within sex and different stages of disease. RESULTS: The mRNA expression of ppGalNAc-T6 and ST6GalNAc-I was significantly higher in serum samples of gastric cancer patients on comparison with controls (p = .008), however, there was no significant difference in mRNA expression of GlcNAcT-V, ST3Gal I, and ST3 Gal IV in serum samples of gastric cancer patients and controls (p = .097). In addition, no significant association of mRNA expression of these glycosyltransferases was found within sex and stages in this study. CONCLUSION: This study revealed the potential of ppGalNAc-T6 and ST6GalNAc-I mRNA transcript levels in serum as markers of gastric cancer. Further studies on the wider range of glycosyltransferases in various cancers are needed to establish signature mRNA batteries as minimally invasive markers of gastric cancer.

Serum antioxidant status in patients with systemic sclerosis.

BACKGROUND: Vascular endothelial dysfunction is a central event in pathogenesis of a variety of human diseases. Systemic sclerosis is one of such diseases. The oxidative stress and depletion of antioxidants in the serum is believed to be one of the factors in causing this dysfunction. AIMS: The aim of this case control study was to compare the levels of antioxidants in the serum of patients with systemic sclerosis and the normal age and sex matched controls. MATERIALS AND METHODS: Our study consisted of 16 successively admitted patients with systemic sclerosis and 16 healthy, age and sex matched controls. The age group of patient's ranged between 25 and 55 years. The duration of the disease in patients ranged from 1 to 8 years. The serum of patients and controls were assayed for the levels of antioxidants (GSH, NO, MDA, SOD and GPX) by spectrophotometry. The statistical method of analysis used was the one sample t-test. RESULTS: THE MEDIAN LEVELS OF ANTIOXIDANTS IN THE CONTROL PATIENTS WERE: SOD-4.14 units/ml; GSH-4.76 units/ml; NO-5.58 nmol/l; MDA-0.53 nmol/l and GPX-49 µmol/l. The levels of NO, GSH and SOD were decreased in these patients with a significant P value (<0.001) whereas the levels of GPX and MDA were normal to increased with a significant P value. CONCLUSION: The depletion of antioxidants and oxidative stress in serum might be responsible for the vascular dysfunction and other hallmark manifestations of systemic sclerosis. Therefore micronutrient antioxidant supplements may be of therapeutic value.