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Summary: Objectives: The objective of the study is to compare the efficacy of hypoglycaemic drugs for type 2 diabetes mellitus (T2DM) by network meta‐analysis of randomized controlled trials (RCTs). Methods: We compared 11 major oral hypoglycaemic drugs under five categories evaluated by RCTs as drug monotherapy for the patients with T2DM, measuring glycosylated haemoglobin (%) or fasting plasma glucose (mmol L−1) as outcomes. RCT quality was assessed with the Cochrane risk of bias tool. Network meta‐analysis estimated the mean differences and 95% credible intervals. Subgroup and sensitivity analyses were performed to determine the results robustness. The Grading of Recommendation, Assessment, Development, and Evaluation evidence strength was assessed. Results: Seventy‐five RCTs including 33,830 patients were identified. Their study quality was high. Regarding glycosylated haemoglobin, top three anti‐diabetics were repaglinide (mean differences −1.39 [95% credible intervals −1.75 to −1.03]), gliclazide (−1.37 [−2.04 to −0.71]) and metformin (−1.13 [−1.37 to −0.90]), against placebo. Regarding fasting plasma glucose, top three anti‐diabetics were repaglinide (−2.01 [−2.75 to −0.97]), metformin (−1.72 [−2.16 to −1.27]) and glipizide (−1.57 [−2.44 to −0.64]), against placebo. There was no difference between metformin and repaglinide. Subgroup and sensitivity analyses found the results to be robust. The evidence strength was moderate to high. Conclusion: This meta‐analysis showed that repaglinide and metformin would be the most efficacious oral drugs for first‐line monotherapy of T2DM. [ABSTRACT FROM AUTHOR]

Under physiological conditions, the endothelium generates vasodilator signals [prostacyclin, nitric oxide NO and endothelium-dependent hyperpolarization ( EDH)], for the regulation of vascular tone. The relative importance of these two signals depends on the diameter of the blood vessels: as the diameter of the arteries decreases, the contribution of EDH to the regulation of vascular tone increases. The mechanism involved in EDH varies with species and blood vessel types; nevertheless, activation of endothelial intermediate- and small-conductance calcium-activated potassium channels ( IKCa and SKCa, respectively) is characteristic of the EDH pathway. IKCa- and SKCa-mediated EDH are reduced with endothelial dysfunction, which develops with ageing and hypertension, and is less pronounced in female than in age-matched male until after menopause. Impaired EDH-mediated relaxation is related to a reduced involvement of SKCa, so that the response becomes more dependent on IKCa. The latter depends on the activation of adenosine monophosphate-activated protein kinase ( AMPK) and silent information regulator T1 ( SIRT1), proteins associated with the process of cellular senescence and vascular signalling in response to the female hormone. An understanding of the role of AMPK and/or SIRT1 in EDH-like responses may help identifying effective pharmacological strategies to prevent the development of vascular complications of different aetiologies. [ABSTRACT FROM AUTHOR]

Background and Purpose Kaempferol, a plant flavonoid present in normal human diet, can modulate vasomotor tone. The present study aimed to elucidate the signalling pathway through which this flavonoid enhanced relaxation of vascular smooth muscle. Experimental Approach The effect of kaempferol on the relaxation of porcine coronary arteries to endothelium-dependent (bradykinin) and -independent (sodium nitroprusside) relaxing agents was studied in an in vitro organ chamber setup. The whole-cell patch-clamp technique was used to determine the effect of kaempferol on potassium channels in porcine coronary artery smooth muscle cells ( PCASMCs). Key Results At a concentration without direct effect on vascular tone, kaempferol (3 × 10−6 M) enhanced relaxations produced by bradykinin and sodium nitroprusside. The potentiation by kaempferol of the bradykinin-induced relaxation was not affected by Nω-nitro- L-arginine methyl ester, an inhibitor of NO synthase (10−4 M) or TRAM-34 plus UCL 1684, inhibitors of intermediate- and small-conductance calcium-activated potassium channels, respectively (10−6 M each), but was abolished by tetraethylammonium chloride, a non-selective inhibitor of calcium-activated potassium channels (10−3 M), and iberiotoxin, a selective inhibitor of large-conductance calcium-activated potassium channel ( KCa1.1; 10−7 M). Iberiotoxin also inhibited the potentiation by kaempferol of sodium nitroprusside-induced relaxations. Kaempferol stimulated an outward-rectifying current in PCASMCs, which was abolished by iberiotoxin. Conclusions and Implications The present results suggest that, in smooth muscle cells of the porcine coronary artery, kaempferol enhanced relaxations caused by endothelium-derived and exogenous NO as well as those due to endothelium-dependent hyperpolarization. This vascular effect of kaempferol involved the activation of KCa1.1 channels. [ABSTRACT FROM AUTHOR]

Summary Mild hypothermia (34-35 °C) increases peri-operative blood loss. We have previously demonstrated the beneficial effect of in vitro desmopressin on impairment of primary haemostasis associated with hypothermia. This study evaluated subcutaneous desmopressin in 52 healthy volunteers, randomly assigned to receive either normal saline or desmopressin 1.5, 5 or 15 μg (with 13 in each group). Blood samples were collected before and 2 h after drug administration and incubated at 32 and 37 °C. Platelet function analyser PFA-100® closure times were measured. Hypothermia at 32 °C prolonged mean (95% CI) closure times (for adenosine diphosphate/collagen by 11.3% (7.5-15.2%) and for adrenaline/collagen by 16.2% (11.3-21.2%); these changes were reversed by desmopressin. A very small dose was found to be effective (1.5 μg); this dose did not significantly change closure times at 37 °C, but fully prevented its prolongation at 32 °C. Subcutaneous desmopressin prevents the development of hypothermia-induced impairment of primary haemostasis. You can respond to this article at [ABSTRACT FROM AUTHOR]

The effects of the radio frequency human exposure to mobile phone, inside both partially and fully enclosed metallic elevators, have been analyzed. It has been found that the evaluated peak Specific Absorption Rate (SAR) and the whole body absorption power are increased only by a small percentage inside the partial enclosures as compared to the free space environment; whereas inside the full enclosure, the peak SAR and the whole body absorption power are significantly increased. The analysis suggest that the reason of such a high level of RF energy absorption inside a fully enclosed metallic elevator is mainly because of the resonance effect. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 2207–2210, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23612 [ABSTRACT FROM AUTHOR]

Radio Frequency Identification (RFID) technology has been widely used in different business sector. Recently, Hong Kong International Airport has adopted the RFID technology, replacing the traditional infra-red bar code system with a new 900 MHz RFID baggage handling system. Besides the technological challenges in the design and the installation, safety issue of workers due to the radiated emission from the RFID system is also an important concern. An electromagnetic assessment of the RFID system is carried out in the post-installation phase, and is presented here. The result shows that the in-situ E-field level recorded for the whole system is well below the ICNIRP guideline reference level. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 49: 924–928, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.22311 [ABSTRACT FROM AUTHOR]

This paper investigates the effects of different ground plane configurations of a typical GSM900/1800 dual-band internal planar inverted-F patch antenna (PIFA) on specific absorption rate (SAR) and corresponding antenna performance. The effect of the length and width of the ground plane and the addition of vertical sidewall on the ground plane are presented. Results have shown that when the length and width of the antenna ground plane is increased, the SAR value could be reduced while radiation efficiency is not significantly affected, the antenna gain is reduced by 3.5 dB at 930 MHz, and the envelope of far-field antenna pattern is mainly affected in the human head direction. The addition of vertical sidewall at four sides of the ground plane with a height of 7 mm could provide a SAR reduction at 1.75 GHz by 63% without significantly affecting the performance of the PIFA antenna. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 49: 949–953, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.22316 [ABSTRACT FROM AUTHOR]

Objective Syntometrine is an effective uterotonic agent used in preventing primary postpartum haemorrhage but has adverse effects including nausea, vomiting, hypertension and coronary artery spasm. Carbetocin is a newly developed long-acting oxytocin analogue that might be used as an uterotonic agent. We compare the efficacy and safety of intramuscular (IM) carbetocin with IM syntometrine in preventing primary postpartum haemorrhage. Design Prospective, double-blinded, randomised controlled trial. Setting Delivery suite of a university-based obstetrics unit. Population Women with singleton pregnancy achieving vaginal delivery after and throughout 34 weeks. Methods Three hundred and twenty-nine eligible women were randomised to receive either a single dose of 100 microgram IM carbetocin or 1 ml IM syntometrine (a mixture of 5 iu oxytocin and 0.5 mg ergometrine) at the end of second stage of labour. Main outcome measures Difference in haemoglobin drop measured 2 days after delivery between the two groups. Results There was no difference in the drop of haemoglobin concentration within the first 48 hours between the two groups. The incidence of additional oxytocic injections, postpartum haemorrhage (blood loss ≥ 500 ml) and retained placenta were also similar. The use of carbetocin was associated with significant lower incidence of nausea (relative risk [RR] 0.18, 95% confidence interval [CI] 0.04–0.78), vomiting (RR 0.1, 95% CI 0.01–0.74), hypertension 30 minutes (0 versus 8 cases, P < 0.01) and 60 minutes (0 versus 6 cases, P < 0.05) after delivery but a higher incidence of maternal tachycardia (RR 1.68, 95% CI 1.03–3.57). Conclusions IM carbetocin is as effective as IM syntometrine in preventing primary postpartum haemorrhage after vaginal delivery. It is less likely to induce hypertension and has a low incidence of adverse effect. It should be considered as a good alternative to conventional uterotonic agents used in managing the third stage of labour. [ABSTRACT FROM AUTHOR]

This paper presents an investigation of the effect of the internal antenna on the specific absorption rate (SAR), and the effect of the presence of a human head at close proximity to a mobile phone upon the antenna performance in mobile-phone applications. Both the experimental measurement and numerical simulation of the SAR values and the antenna performance parameters of a typical internal antenna are presented. The results indicate that the far-field radiations of the internal antenna can be reduced by 3 dB with the presence of human head. © 2005 Wiley Periodicals, Inc. Microwave Opt Technol Lett 45:286–290, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20797 [ABSTRACT FROM AUTHOR]

Adding an external shield to mobile phones is one of the common methods adopted for the reduction of the specific absorption rate (SAR), which is the safety level of human exposure to radiated electromagnetic fields from mobile phones. This paper provides an experimental study on the effectiveness of SAR reduction by attaching conductive materials to mobile phones, and the corresponding effects of the antenna performance of the mobile phones. The results show a typical trade-off of a 20% reduction in the SAR value with a maximum 1.8-dB reduction in the received power of the antenna. The results also conclude that the attachment position of the shielding material is an important factor, whereby the hot spot of the SAR distribution of the mobile phone must be well covered in order to achieve good SAR reduction. © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 44: 140–144, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20569 [ABSTRACT FROM AUTHOR]

The specific absorption rate (SAR) on a human head due to the radiation of mobile phones can be influenced by many parameters, including the phones' antenna design and profile. In this paper, an experimental study of the characteristics of the SAR of mobile phones is presented. Statistical results illustrate that mobile phones, in general, satisfy the ICNIRP safety limit, and that the SAR values are affected by the transmission frequency of mobile phones. In most cases, the maximum SAR is at the cheek position and is twice that at the ear position. We conclude that there is no significant difference in the SAR value between phones with internal and external antennas and that, at the ear position, the SAR value of the flip phones is about 22% lower than that of nonflip phones. We also conclude that the SAR hot spot is generally located near the antenna position. © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 40: 22–26, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.11275 [ABSTRACT FROM AUTHOR]

Electrostatic discharge (ESD) on the metallic enclosure of electronic products normally generates unwanted radiated electromagnetic interference (EMI). The radiated EMI penetrates through the apertures on the enclosure and then couples to the circuitries inside the enclosure. This may cause malfunction and signal errors to the circuitries. In this paper, an experimental investigation on the effects of induced noise level caused due to different injection locations of ESD on the metallic enclosure with different aperture sizes is carried out. Results show that the induced voltage is highly sensitive to injection location of ESD. © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 38: 203–206, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.11015 [ABSTRACT FROM AUTHOR]

There has been a recent increase in public concern regarding human safety due to the exposure of humans to radio frequency (RF) electromagnetic energy radiated by mobile phone handsets. This paper presents an experimental study of the effectiveness of various commercially available specific absorption rate (SAR) reduction products and shielding materials that can be externally attached to the handsets. The results have indicated that the effectiveness of both the SAR reduction products and the shielding materials in reducing SARs are generally below 10%. © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 36: 419–422, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.10780 [ABSTRACT FROM AUTHOR]

In this paper, a “local wave” concept using the generalized 2-D transmission-line equation (GTLE) to model the ground bounce (GB) effect in PCBs is described. The model is then used to characterize the GB effect in PCBs for both the power/ground and the trace/ground configuration. Simulation results for both configurations are presented. © 2002 John Wiley & Sons, Inc. Microwave Opt Technol Lett 32: 259–264, 2002. [ABSTRACT FROM AUTHOR]

A new model based on dyadic Green's functions for the fast and efficient prediction of crosstalk between traces in PCBs is presented here. The model is simple to set up, is capable of dealing with PCBs that have many traces, and gives accurate results. © 2001 John Wiley & Sons, Inc. Microwave Opt Technol Lett 30: 142–144, 2001. [ABSTRACT FROM AUTHOR]

Originally published Microwave Opt Technol Lett 50 (2008), 2207–2210. [ABSTRACT FROM AUTHOR]

1. Current evidence suggests that lysophosphatidylcholine (LPC), a component found in oxidized low-density lipoprotein (Ox-LDL), inhibits endothelium-dependent relaxation (EDR) mediated by endothelium-derived relaxing factor (EDRF) and endothelium-derived hyperpolarizing factor (EDHF). An objective of the present study was to characterize the roles of the different elements of EDR in LPC-induced impairment within the porcine coronary artery. Concomitantly, we sought to determine whether impairment of one component of EDR would increase the sensitivity of the endothelium to LPC. 2. Bradykinin (0.1 nmol/L -0.3 mumol/L) relaxed U46,619 (30 nmol/L)-precontracted porcine coronary artery rings in a concentration-dependent manner. A reduction in the bradykinin-elicited response was observed in NG-nitro-L-arginine methyl ester (L-NAME; 300 mumol/L)- and ouabain (50 mumol/L)-treated rings. Pretreatment with LPC (20 mumol/L), which on its own had no effect on normal endothelial relaxation, resulted in further inhibition of EDRF- and EDHF-induced relaxations. 3. Our results demonstrate that EDRF and EDHF are the primary mediators of EDR in the porcine coronary artery. Our data also show that while a low concentration of LPC (20 mumol/L) does not impair EDR, it can evoke vascular dysfunction following blockade of either the effects of EDRF or EDHF. Therefore, these data suggest that the partially damaged vascular endothelium could be more sensitive to threshold levels of this atherogenic phospholipid.