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Demographic, clinical and lifestyle predictors for severity of erectile dysfunction and biomarkers level in Malaysian patients
No full textThe incidence of erectile dysfunction (ED) is rising worldwide and its prevalence is one of the main health concerns that affect overall men well-being in Malaysia. The cluster of demographic, clinical and lifestyle factors may have contributed to the severity of ED and changes in biomarkers level; nevertheless these have not been studied extensively. This cross sectional study involved a total of 276 patients with 138 was diagnosed with ED. The demographic, clinical, lifestyle factors and severity of ED were assessed using a set of questionnaire and the International Index of Erectile Function (IIEF-5). Meanwhile, Total Testosterone (TT) and Asymmetric dimethylarginine (ADMA) levels were determined using the enzyme-linked immunosorbant assay (ELISA). Binary logistic regression test was used to demonstrate the predictors of severity of ED, TT and ADMA levels. Significant predictors for worsening of severity of ED are self-employed [10.55 (0.43 – 257.06), p=0.004], pensioner [8.07 (0.19 – 352.45), p=0.026], non-government employee [1.16 (0.05 – 26.26), p=0.04] and TT [0.41 (0.25 – 0.69), p=0.001]. Nevertheless, pensioner [0.08 (0.01 – 0.87), p=0.038] and unemployed [0.04 (0.01 – 0.42), p=0.007], were the predictors that may influence the changes of TT levels. On the other hand, academic qualification (secondary) [4.51 (0.48 – 42.83), p=0.014] and intensity of physical activities (< 1 hour/day) [2.61 (0.65 – 10.48), p=0.008] were the predictors which were more likely to influence the changes of ADMA levels in ED patients. TT and ADMA levels were influenced by demographic and lifestyle factors whilst severity of ED was predicted by demographic and clinical factors in Malaysian ED population. These predictors may provide new knowledge on risk factors of severity of ED and help in management of ED. Thus, the predictive models could serve as a primary guidance to physicians to ensure ED being managed and treated more effectively
Measuring transaction performance based on storage approaches of Native XML database
No full textMany organizations today store their critical business information permanently in XML format. XML data can be managed using: XML-Enabled Database (XED) systems which convert and store XML files in traditional database systems; Native XML Database (NXD) systems which store XML data natively using three main storage technologies – text-based, model-based, and schema-based techniques; and Hybrid Database systems which are comprised of both XML-Enabled and Native XML database systems. NXDs are faster than other database technologies because there is no need to convert the format of the data prior to storage. No performance evaluation has been carried out to compare all three storage strategies, hence, this paper reports on the first attempt to evaluate all three storage strategies by using open source products to measure the response time taken for each of the database basic tasks such as database creation, dataset insertion, and data manipulation. The results of the evaluation show that the schema-based storage strategy: performs 3.5 times faster than the other two storage techniques in data insertion; shows very good performance in query processing on small and large datasets; performs 10.33 times faster than text-based, and 7.5 times faster than model-based storage techniques in query processing of large datasets
Downlink Rate Analysis of Training-Based Massive MIMO Systems With Wireless Backhaul Networks
No full textMassive multiple-input multiple-output (MIMO) systems with wireless backhaul networks have been considered as a candidate technology for 5G. Despite their potential, these systems still require improvement in areas such as resource allocation and interference management. In this paper, we derive a closed-form lower bound ergodic downlink rate expression for training-based multicell massive MIMO systems with full duplex wireless backhaul networks. We also propose a wireless backhaul link selection method, in which only certain access points will be activated and only certain users will use wireless backhaul links. The results show that the wireless backhaul with a link selection method can improve the downlink rate compared to other methods. The downlink rate of the minimum rate users can be significantly improved by prioritizing the wireless backhaul links for the minimum rate users. Power analysis shows that there is concave relationship between access point transmit power and median downlink rate. The results also show that the optimum access point transmit power is much lower than the standard transmit power from the users and base station. Additional investigation shows that users are more likely to use backhaul links when they are located farther from the base station. We also demonstrate that as the number of spatial multiplexed users increases, the performance improvement provided by wireless backhaul system decreases
Anthocyanin as potential source for antimicrobial activity in Clitoria ternatea L. and Dioscorea alata L.
No full textPurpose: The purpose of this paper is to validate the antimicrobial activity (both antibacterial and antifungal) of in vivo and in vitro ethanolic anthocyanin extracts of Clitoria ternatea L. (vivid blue flower butterfly-pea) and Dioscorea alata L. (purple yam) against selected bacteria (Bacillus subtilis, Staphylococcus aureus and Escherichia coli) and fungi (Fusarium sp., Aspergillus niger and Trichoderma sp.). Design/methodology/approach: The freeze-dried samples (0.2 g) from in vivo vivid blue flowers of C. ternatea L. were extracted using 10 mL ethanol (produced ethanolic red extraction) and 10 mL distilled water (produced aqueous blue extraction) separately. Two-month-old in vitro callus samples (0.2 g) were only extracted using 10 mL ethanol. The anthocyanin extractions were separated with the addition (several times) of ethyl acetate and distilled water (1:2:3) to remove stilbenoids, chlorophyll, less polar flavonoids and other non-polar compounds. Furthermore, the antimicrobial properties were determined using agar diffusion technique. Three bacteria (B. subtilis, S. aureus and E. coli) and fungi (F. sp., A. niger and T. sp.) were streaked on bacteria agar and dextrose agar, respectively, using “hockey stick”. Then, the sterile paper discs (6 mm diameter) were pipetted with 20 µL of 1,010 CFU/mL chloramphenicol (as control for antibacterial) and carbendazim (as control for antifungal) in vivo and in vitro extracts. The plates were incubated at room temperature for 48 h, and the inhibition zones were measured. Findings: Based on the results, both in vivo and in vitro ethanolic extracts from vivid blue flowers of C. ternatea L. showed the best antibacterial activity against the same bacteria (B. subtilis), 11 and 10 mm inhibition zones, respectively. However, different antifungal activity was detected in in vitro ethanolic callus extract (12 mm), which was against T. sp., contrary to in vivo ethanolic extract (10 mm), which was against F. sp.; antibacterial activity of D. alata L. was seen against the same bacteria (E. coli) with the highest inhibition zone for in vivo extract (8.8 mm), followed by in vitro extract (7.8 mm). Research limitations/implications: Anthocyanins are responsible for the water soluble and vacuolar, pink, red, purple and blue pigments present in coloured plant pigments. These pigments (pink, red, purple and blue) are of important agronomic value in many crops and ornamental plants. However, anthocyanins are not stable and are easy to degrade and fade whenever exposed to light. Social implications: Plant extracts containing bioactive agents with antimicrobial properties have been found to be useful in treating bacterial and fungal infections, as well as showed multiple antibiotic resistance. Originality/value: Both in vivo and in vitro extracts from vivid blue flower petals (C. ternatea L.) and purple yam (D. alata L.) have important applications as natural antimicrobial (antibacterial and antifungal) agents in the coating industry, instead of natural pharmaceutical products
EBV-encoded miRNAs target ATM-mediated response in nasopharyngeal carcinoma
No full textNasopharyngeal carcinoma (NPC) is a highly invasive epithelial malignancy that is prevalent in southern China and Southeast Asia. It is consistently associated with latent Epstein–Barr virus (EBV) infection. In NPC, miR-BARTs, the EBV-encoded miRNAs derived from BamH1-A rightward transcripts, are abundantly expressed and contribute to cancer development by targeting various cellular and viral genes. In this study, we establish a comprehensive transcriptional profile of EBV-encoded miRNAs in a panel of NPC patient-derived xenografts and an EBV-positive NPC cell line by small RNA sequencing. Among the 40 miR-BARTs, predominant expression of 22 miRNAs was consistently detected in these tumors. Among the abundantly expressed EBV-miRNAs, BART5-5p, BART7-3p, BART9-3p, and BART14-3p could negatively regulate the expression of a key DNA double-strand break (DSB) repair gene, ataxia telangiectasia mutated (ATM), by binding to multiple sites on its 3'-UTR. Notably, the expression of these four miR-BARTs represented more than 10% of all EBV-encoded miRNAs in tumor cells, while downregulation of ATM expression was commonly detected in all of our tested sequenced samples. In addition, downregulation of ATM was also observed in primary NPC tissues in both qRT-PCR (16 NP and 45 NPC cases) and immunohistochemical staining (35 NP and 46 NPC cases) analysis. Modulation of ATM expression by BART5-5p, BART7-3p, BART9-3p, and BART14-3p was demonstrated in the transient transfection assays. These findings suggest that EBV uses miRNA machinery as a key mechanism to control the ATM signaling pathway in NPC cells. By suppressing these endogenous miR-BARTs in EBV-positive NPC cells, we further demonstrated the novel function of miR-BARTs in inhibiting Zta-induced lytic reactivation. These findings imply that the four viral miRNAs work co-operatively to modulate ATM activity in response to DNA damage and to maintain viral latency, contributing to the tumorigenesis of NPC
Is the risk of tenofovir-induced nephrotoxicity similar in treatment-naïve compared to treatment-experienced patients?
No full textBackground: Tenofovir disoproxil fumarate (TDF) is the recommended first-line nucleoside reverse transcriptase inhibitor (NRTI) in the management of human immunodeficiency virus (HIV); however, its use is associated with nephrotoxicity. Aim: To assess if the risks of renal impairment were similar in treatment-naïve compared to treatment-experienced patients initiating tenofovir given their different background clinical characteristics. Method: This was a retrospective observational study conducted at the University Malaya Medical Centre, Malaysia and included all HIV-infected adults who received tenofovir for at least 3 months and had an estimated glomerular filtration rate (eGFR) >60 mL/min at tenofovir initiation. The incidence of renal impairment was defined as a 25% decrease in eGFR from baseline or the development of chronic kidney disease. Clinical and demographic characteristics were extracted from medical records. Risk factors associated with tenofovir-induced renal impairment were determined using multivariate logistic regression. Results: This study included 314 patients and almost half of them (49%) were treatment-naïve at tenofovir initiation. The majority of patients were male (89.5%) with a median (interquartile range) baseline creatinine clearance of 99.1 mL/min (85.0–114.0). Thirty (9.4%) patients developed tenofovir-induced renal impairment and the incidence rate was higher in treatment-experienced versus treatment-naïve patients (7.0 vs 3.3 cases/100 person-years, p = 0.049). Risk factors associated with tenofovir-induced nephrotoxicity in multivariate analysis were older age (p = 0.001), anaemia (p = 0.027), concurrent hypertension (p = 0.014) and higher baseline eGFR (p = 0.007). Conclusion: Treatment experience was not an independent risk factor but was rather confounded by multiple characteristics associated with an increased risk of TDF-induced nephrotoxicity. Monitoring all patients presenting with these risks regardless of treatment experience is crucial
Deep eutectic solvent and inorganic salt pretreatment of lignocellulosic biomass for improving xylose recovery
No full textDeep eutectic solvents (DESs) have received considerable attention in recent years due to their low cost, low toxicity, and biodegradable properties. In this study, a sequential pretreatment comprising of a DES (choline chloride:urea in a ratio of 1:2) and divalent inorganic salt (CuCl 2 ) was evaluated, with the aim of recovering xylose from oil palm fronds (OPF). At a solid-to-liquid ratio of 1:10 (w/v), DES alone was ineffective in promoting xylose extraction from OPF. However, a combination of DES (120 °C, 4 h) and 0.4 mol/L of CuCl 2 (120 °C, 30 min) resulted in a pretreatment hydrolysate containing 14.76 g/L of xylose, remarkably yielding 25% more xylose than the CuCl 2 -only pretreatment (11.87 g/L). Characterization studies such as FE-SEM, BET, XRD, and FTIR confirmed the delignification of OPF when DES was implemented. Thus, the use of this integrated pretreatment system enabled xylose recoveries which were comparable with other traditional pretreatments
Emission of short-lived halocarbons by three common tropical marine microalgae during batch culture
No full textVery short-lived halocarbons of marine biogenic origin play an important role in affecting tropospheric and stratospheric chemistry. In recent years, more attention has been paid to tropical regions where the influence of strong convective forces is responsible for rapid uplifting of the volatile organohalogens from the open surface waters into the atmosphere. This laboratory-based study reports on three common tropical marine microalgae capable of emitting a range of short-lived halocarbons, namely, CH3I, CHBr3, CH2Br2, CHBr2Cl, and CHCl3. Chlorophyll a and cell density were highly correlated to the quantity of all five compounds emitted (p < 0.01). The diatom Amphora sp. UMACC 370 had a higher range of CH3I emission rate (10.55–64.18 pmol mg−1 chl a day−1, p < 0.01) than the cyanobacterium Synechococcus sp. UMACC 371 and chlorophyte Parachlorella sp. UMACC 245 (1.04–3.86 pmol mg−1 chl a day−1 and 0–2.16 pmol mg−1 chl a day−1, p < 0.01, respectively). Furthermore, iodine was the dominant halogen emitted in terms of total combined halide mass of all three species. Overall, the emissions of short-lived halocarbons were both species- and growth phase-dependent, highlighting the importance of considering cell physiological conditions when determining gas emission rates
Application of Two-Level Full Factorial Design for the Extraction of Fucoxanthin and Antioxidant Activities from Sargassum siliquosum and Sargassum polycystum
No full textTwo-level full factorial design was employed to identify the extraction parameters that can improve the derivation of fucoxanthin content (FC), total carotenoid content (TCC), and antioxidant from two brown seaweeds, Sargassum siliquosum (SS) and Sargassum polycystum (SP). These parameters included temperature (A: 4–45°C), time (B: 30–1,440 min), and solvent-to-solid ratio (C: 10–50 ml/g). Antioxidant activities were determined as trolox equivalent antioxidant capacity (TEAC), 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging activity, and ferric-reducing antioxidant power (FRAP). Results showed that all three factors were significant (p < 0.05) in providing higher FC in both species. These factors were also significant in obtaining higher TCC in SS; whereas in SP, TCC was only affected by solvent-to-solid ratio. Only temperature was found to contribute significantly to a higher TEAC in both species. However, none of the factors improved DPPH for SS, except temperature and time for SP. For SS, only time was significant in obtaining higher FRAP; whereas temperature and time were significant for SP. Hence, results indicate that a simple modification in the extraction temperature, time, and solvent-to-solid ratio will be able to improve the derivation of fucoxanthin, carotenoids, and antioxidant activities