Effect of salt intake and potassium supplementation on brachial-ankle pulse wave velocity in Chinese subjects: an interventional study

Accumulating evidence has suggested that high salt and potassium might be associated with vascular function. The aim of this study was to investigate the effect of salt intake and potassium supplementation on brachial-ankle pulse wave velocity (PWV) in Chinese subjects. Forty-nine subjects (28-65 years of age) were selected from a rural community of northern China. All subjects were sequentially maintained on a low-salt diet for 7 days (3.0 g/day NaCl), a high-salt diet for an additional 7 days (18.0 g/day NaCl), and a high-salt diet with potassium supplementation for a final 7 days (18.0 g/day NaCl+4.5 g/day KCl). Brachial-ankle PWV was measured at baseline and on the last day of each intervention. Blood pressure levels were significantly increased from the low-salt to high-salt diet, and decreased from the high-salt diet to high-salt plus potassium supplementation. Baseline brachial-ankle PWV in salt-sensitive subjects was significantly higher than in salt-resistant subjects. There was no significant change in brachial-ankle PWV among the 3 intervention periods in salt-sensitive, salt-resistant, or total subjects. No significant correlations were found between brachial-ankle PWV and 24-h sodium and potassium excretions. Our study indicates that dietary salt intake and potassium supplementation, at least in the short term, had no significant effect on brachial-ankle PWV in Chinese subjects.

IRX3 is a genetic modifier for birth weight, adolescent obesity and transaminase metabolism

OBJECTIVE

IRX3 expression has been functionally associated in obesity-associated long-distance susceptibility loci, but the effect of the IRX3 genetic variants on human obesity and obesity-related metabolism remains uncertain.

METHODS

To determine the genetic role of IRX3, we conducted a molecular epidemiological analysis using three haplotype tagging single nucleotide polymorphisms (SNPs; rs8053360, rs3751723 and rs12445085) and one nonsynonymous SNP (rs1126960) at the IRX3 locus in 333 junior and senior high school students from a northeast Chinese population.

RESULTS

We identified significant associations between IRX3 SNPs and birth weight, body mass index (BMI), aspartate aminotransferase (AST), alanine aminotransferase (ALT) and AST/ALT ratio. The rs8053360 CC and rs1126960 GG genotypes were associated with increased birth weight and BMI, especially in females. Individuals with the rs12445085 TT genotype had significantly higher levels of AST and ALT, whereas individuals with the rs1126960 GG genotype had a significantly lower AST/ALT ratio than did individuals with other genotypes. However, no significant relationships were found between any of the IRX3 SNPs and metabolic syndrome or diabetes.

CONCLUSIONS

IRX3 genetic variants associate with birth weight, BMI and AST/ALT-related transaminase metabolism, supporting the role of IRX3 as an obesity-associated susceptibility gene.

Effect of denervation of carotid labyrinths on breathing in unrestrained Xenopus laevis

The effect of denervation of the carotid labyrinths on breathing responses to simultaneously applied aerial and aquatic normoxia, hypoxia, or hypercapnia has been studied in unrestrained Xenopus laevis. Denervation significantly reduced VI of normoxic toads compared with VI in intact and sham-operated toads, due to a significant reduction in the volume of each buccal pumping movement (VB) in denervates. Breathing increased significantly in response to environmental hypoxia or hypercapnia in intact and sham-operated toads as well as in denervates. Breathing frequency (fRESP) was the major determinant of the increase in VI for VB was unchanged and even fell slightly in denervates in hypercapnia. Dive time (DT) was significantly reduced in both hypoxia and hypercapnia, from that in normoxia. DT fell significantly more in hypoxia than in hypercapnia in both denervates and intact and sham-operated toads. It is concluded that the carotid labyrinth does not play a major role in regulating breathing in hypoxia or hypercapnia in unrestrained Xenopus.

Fabrication and characterization of hydroxyapatite reinforced with 20 vol % Ti particles for use as hard tissue replacement

Hydroxyapatite(HA)-based composite reinforced with 20 vol % titanium (Ti) particles was fabricated by hot pressing based on the studies of the structural stability of HA phase in HA-Ti composite by means of FTIR spectrometry and X-ray diffractometry. The mechanical properties and biological behaviors of the composite were investigated by mechanical and in vivo studies. The existence of Ti metal phase can promote the dehydration and decomposition of HA ceramic phase into the more stable calcium phosphate phases, such as alpha-Ca(3)(PO(4))(2) (alpha-TCP) and Ca(4)O(PO(4))(2) at high temperatures. Comparing with pure HA ceramic manufactured under the same conditions, HA-20 vol % Ti composite with higher fracture toughness (0.987 MPa m(1/2)), bending strength (78.59 MPa), work of fracture (12.8J/m(2)), porosity (9.8%) and lower elastic modulus (75.91 GPa) is more suitable for use as hard tissue replacement. Crack deflection is the chief toughening mechanism in the composite. Histological evaluation by light microscope shows HA-20 vol % Ti composite implant could be partially integrated with newborn bone tissues after 3 weeks and fully osteointegrated at 12 weeks in vivo. The excellent biological properties of HA-20 vol % Ti composite may be contributed to the coexistence of high porosity and the decomposition products of HA phase in the composite.

High-performance blue OLED using multiresonance thermally activated delayed fluorescence host materials containing silicon atoms

We report three highly efficient multiresonance thermally activated delayed fluorescence blue-emitter host materials that include 5,9-dioxa-13b-boranaphtho[3,2,1-de]anthracene (DOBNA) and tetraphenylsilyl groups. The host materials doped with the conventional N7,N7,N13,N13,5,9,11,15-octaphenyl-5,9,11,15-tetrahydro-5,9,11,15-tetraaza-19b,20b-diboradinaphtho[3,2,1-de:1',2',3'-jk]pentacene-7,13-diamine (ν-DABNA) blue emitter exhibit a high photoluminescence quantum yield greater than 0.82, a high horizontal orientation greater than 88%, and a short photoluminescence decay time of 0.96-1.93 μs. Among devices fabricated using six synthesized compounds, the device with (4-(2,12-di-tert-butyl-5,9-dioxa-13b-boranaphtho[3,2,1-de]anthracen-7-yl)phenyl)triphenylsilane (TDBA-Si) shows high external quantum efficiency values of 36.2/35.0/31.3% at maximum luminance/500 cd m-2/1,000 cd m-2. This high performance is attributed to fast energy transfer from the host to the dopant. Other factors possibly contributing to the high performance are a T1 excited-state contribution, inhibition of aggregation by the bulky tetraphenylsilyl groups, high horizontal orientation, and high thermal stability. We achieve a high efficiency greater than 30% and a small roll-off value of 4.9% at 1,000 cd m-2 using the TDBA-Si host material.

Compensatory and maladaptive responses to cardiac dysfunction

The past few years have witnessed an extraordinary number of important developments in the study of compensatory and maladaptive responses to cardiac dysfunction. It now seems clear that the process whereby the heart remodels in response to left ventricular injury is of paramount importance in the expression of clinical heart failure. There have been parallel attempts by basic scientists and clinical investigators to understand better the fundamental biologic processes that underlie remodeling and to assess numerous new treatments--especially angiotensin-converting enzyme inhibitors. A general consensus seems to be emerging that holds that the response of the heart to acute injury includes a number of highly compensatory and adaptive mechanisms that ultimately become maladaptive and contribute to cardiomegaly and severe congestive heart failure. Such mechanisms undoubtedly include local and systemic release of cytokines, peptides, and neurohormones, and altered loading conditions leading to unusual mechanical forces on cardiac myocytes and other cells of the heart. At the organ level there is hypertrophy, dilatation and growth of the interstitium. Preliminary evidence also suggests there may be some "remodeling" at the cardiac myocyte level. Reduction in peripheral vasodilator reserve is seen in experimental animal models of heart failure. Patients with heart failure also develop an endothelial-dependent form of peripheral vascular dysfunction expressed clinically as an attenuated ability to dilate in response to such stimuli as acetylcholine. The transition point whereby these myocardial and peripheral vascular abnormalities become clearly dysfunctional and contribute toward the full clinical expression of heart failure remains to be further investigated.

Emergency Caesarean Section in a Patient with Myotonic Dystrophy: A Case of Failed Postoperative Extubation in a Patient with Mild Disease

A 21-year-old primiparous patient with subclinical myotonic dystrophy presented at a tertiary hospital at 38 weeks gestation in active labour, having previously been reviewed in the high-risk pregnancy clinic. A non-reassuring cardiotocogram and raised foetal scalp lactate necessitated an emergency caesarean section. On extubation following an otherwise unremarkable general anaesthetic, the patient required prompt re-intubation due to respiratory compromise, followed by a more gradual period of weaning from positive pressure ventilation. This review explores the implications of myotonic dystrophy for anaesthesia, discusses its multi-system involvement and highlights the difficulties in identifying at-risk patients in the perioperative setting.

The effect of delayed reperfusion following infarction in the rat on structural changes in viable myocardium

OBJECTIVE

Evidence indicates that patency of the infarct related artery following the completion of myocardial necrosis can attenuate ventricular remodeling. Data have also demonstrated that inhibition of infarct expansion contributes to the anti-remodeling effect of delayed reperfusion. However, the influence of a patent artery on components of the remodeling process in the viable myocardium is poorly understood.

METHODS

Myocyte morphometrics (isolated cell technique) and collagen content (hydroxyproline analysis) were assessed 28 days following experimental myocardial infarction from rats with permanently ligated left coronary vessels (NRP; n = 10) compared with rats who underwent reperfusion 150 minutes after ligation (RP; n = 11) and a sham-operated group (n = 10).

RESULTS

Analysis of infarct size (planimetry) in a separate group of rats demonstrated that reperfusion at this late time point did not reduce infarct size (NRP: 33 +/- 3 vs. RP: 35 +/- 5%). Myocyte length in RP rats was less than in NRP rats in viable, non-infarcted left ventricular tissue (155 +/- 3 vs. 167 +/- 4 microns, p = 0.02), in the right ventricle (154 +/- 4 vs. 167 +/- 3 microns, p = 0.02) and in the septum (158 +/- 4 vs. 169 +/- 4 microns, p = 0.05). Reperfusion also attenuated the expected increase in cell volume compared with NRP rats (left ventricle 39.4 +/- 1.7 x 10(3) vs. 44.1 +/- 1.6 x 10(3) micron 3, p = 0.06; right ventricle 36.7 +/- 1.6 x 10(3) vs. 42.7 +/- 2.0 x 10(3) micron 3, p = 0.02; septum 41.0 +/- 1.6 x 10(3) vs. 44.2 +/- 1.8 x 10(3) micron 3, p = 0.19). Hydroxyproline content increased in the viable left ventricular tissue in both the reperfused and non-reperfused groups.

CONCLUSION

Reperfusion without myocardial salvage attenuates the increase in myocyte length and volume that occurs in remodeling myocardium following infarction in the rat, with no effect on the increase in collagen content. These data indicate that patency of the infarct vessel, which is known to have an inhibitory effect on infarct expansion, also has an anti-remodeling effect remote from the area perfused by this artery.

Generic drug prescriptions following hospital discharge: a prospective study in France

AIMS

Systematic generic prescription at discharge could reduce confusion on drug-name usage, decrease commercial influence on medicine, and reduce drug-related expenditures. This study aimed to analyze generic drug prescriptions at discharge from hospital and to estimate the potential savings associated with a total substitution policy (substitution of every substitutable drug for its cheapest generic counterpart).

METHODS

Drug prescriptions before admission and at discharge of all patients from three medical units of a university hospital were prospectively collected for five weeks without informing prescribers.

RESULTS

Prescriptions from 85 patients were analyzed. On admission, 68 patients (80%) received 413 drugs; 141 were substitutable brand-name drugs and 23 (16%), which were directly prescribed as generics. At discharge, 488 drugs were prescribed to the 85 patients; 180 were substitutable drugs but only 5 (2.8%) were written as generics on prescription pads, a decrease of 78% (p<0.0001) compared to admission. In average, generics were 18% less expensive than brand-name drugs. Some common therapeutic classes offered even greater price difference, such as proton-pump inhibitors (42%), statins (32%), or antihypertensive agents (28%). Potential savings from a total substitution policy at discharge were estimated to €1512 per 1000 patients per week; for lifetime drugs, savings amounted to €18,960 per 1000 patients per year.

CONCLUSIONS

Very few drugs are written as generics on medical forms at discharge in France. Hospital practitioners should be encouraged to prescribe generics, particularly in chronic diseases. A broad generic prescription policy at hospital discharge would result in substantial savings for health insurance.

Extended nucleotide sequence of the switch region of the murine gene encoding immunoglobulin E

The nucleotide sequence of the switch region (S epsilon) of the gene encoding murine IgE was determined from a germline DNA clone. The sequence extends 1.7 kb 5' to the previously published S epsilon sequence. Another 33 repeat units were located by comparison to the S epsilon consensus sequence. Therefore, the complete S epsilon repetitive sequence consists of 53 repeat units contained in a region about 2.5 kb long.

Detection of infection with human immunodeficiency virus type 1 before seroconversion: correlation with clinical symptoms and outcome

Early (pre-seroconversion) infection with human immunodeficiency virus type 1 (HIV-1) was identified in 50 of 267 participants in the Multicenter AIDS Cohort Study. These 50 men had a positive EIA result, which detected IgM antibody (n = 35), p24 antigen, or serum HIV RNA (n = 15) at their last "seronegative" visit. At that visit, the mean CD4 lymphocyte number (890/mm3 vs. 1038/mm3) was significantly lower than in men who subsequently seroconverted but had no evidence of early infection. The decline in CD4 cells was slower and the duration of AIDS-free time longer in the 19 men who were symptomatic in comparison to the 31 asymptomatic men with early infection, but differences were not significant.

Conduction mechanisms and stability of single molecule nanoparticle/molecule/nanoparticle junctions

Nanoparticle/molecule/nanoparticle dimer assemblies have been successfully trapped by dielectrophoresis across nanogap electrodes, enabling temperature dependent charge transport measurements through an oligomeric phenylene ethynylene molecule, and transition from direct tunnelling to Fowler-Nordheim tunnelling is observed at approximately 1.5 V. Samples formed by dielectrophoresis show better contact stability than those formed by receding meniscus. The junction shows stable operation over several weeks in a vacuum, but current increases with time upon exposure to air, possibly due to the adsorbed water molecules near the molecule/gold nanoparticle contacts.

Prospective evaluation of front-line chemo-immunotherapy (C-IT) with oregovomab (2 alternative dosing schedules) carboplatin-paclitaxel (C-P) in advanced ovarian cancer (OC)

3024

Background: Chemotherapy (C) induced bone marrow suppression has been assumed to inhibit the generation of augmented immune responses. This has limited investigation of front-line C-IT in OC. Temporal relationship of IT administration relative to C has not been established. Oregovomab is a CA125 specific MAb in development as an OC adjuvant treatment to induce tumor specific immunity. Methods: Patients (pts) awaiting staging laparotomy for presumptive OC were consented to the study and contributed primary tumor samples. Qualifying pts were subsequently randomized to concurrent C-IT with antibody administered at cycles 1, 3, and 5 (Arm A) or 8 ± 2 days following cycles 1, 3, and 5 (Arm B) of standard C-P. Both arms received additional infusions of oregovomab every 12 weeks until progression; response to C-IT was assessed at 36 weeks. Results: Forty stage III/IV pts (18 Arm A; 22 Arm B) were randomized and dosed. More pts in Arm A (39%) were stage IV vs Arm B (14%) however 27% of Arm B pts had >2cm residual disease vs. 11% in Arm A. Complete clinical response (CR) to surgery and C-IT was achieved in 15 pts (83%) in Arm A and 17 pts (77%) in Arm B. For pts with = 2 cm residual disease, 88% in Arm A had = 65 U/mL CA125 prior to/at cycle 3, normalized CA125 and a CR post C-IT compared to 75% of pts in Arm B. Robust Ab2 antibody response (>100 ng/mL) was achieved in 94% of Arm A and 68% of Arm B pts. The immune response developed earlier in Arm A. After one injection of oregovomab, 31% of pts in Arm A vs. 0% in Arm B generated HAMA > 3000 ng/mL and Ab2 > 100 ng/mL (P=0.016 Fisher’s Exact Test). Such an early and vigorous response pattern has not been seen in previous oregovomab studies which have not included concomitant front-line C. There were no IT related serious adverse events. Conclusions: Contrary to expectations, concurrent C-P resulted in enhanced immune stimulation with oregovomab. Interestingly, concurrent infusion of oregovomab was more immunogenic than delayed infusion. Clinical activity was favorable and safety profiles were similar to that expected for C alone. Further randomized evaluation of front-line CP-oregovomab vs CP is warranted.

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Resource intensity weighing and case mix grouping: assumptions and implications for health service performance evaluation

The use of Resource Intensity Weights (RIWs*) for equity funding and utilization management assumes validity of the cost estimates, reliability of the patient categorization scheme, equivalence of the bases for cost comparison, and equity of the subsequent resource distribution. This paper examines these assumptions, and concludes that caution must be taken when using the current RIWs and Case Mix Groups (CMGs*) for resource allocation and performance evaluation purposes. RIW has represented a milestone in the history of Canadian health care product costing and management. It would be prudent for health care professionals at the operational level to provide structured and continuing feedback that can contribute to the validation and refinement of these valuable management tools.

Liquid crystal adaptive lens: beam translation and field meshing

The liquid crystal adaptive lens (LCAL) is an electrooptic device that emulates a variable focal length lens. The LCAL focuses light by creating a parabolic refractive-index profile across the aperture of a liquid crystal cell. The focal length is electronically controlled by applying appropriate voltages to the array of independent electrodes, thus grading the refractive index of the liquid crystal material across the aperture. Beam translation perpendicular to the optical beam path is described theoretically and demonstrated. This capability coupled with the LCAL's programmable focal length allows 3-D beam control. Meshing, the smoothing of the refractive index between adjacent electrodes, is a critical parameter in achieving near diffraction-limited optical performance. Using two planar electrodes and a ground plane immersed in an isotropic dielectric as a model, a steady-state dc theoretical computer simulation is compared with experiment. Improvements in the liquid crystal cell design demonstrate improved performance over previous LCALs. A larger number of electrodes creates an image without spatial aliasing within the aperture.

Automated otolith image classification with multiple views: an evaluation on Sciaenidae

Combined multiple 2D views (proximal, anterior and ventral aspects) of the sagittal otolith are proposed here as a method to capture shape information for fish classification. Classification performance of single view compared with combined 2D views show improved classification accuracy of the latter, for nine species of Sciaenidae. The effects of shape description methods (shape indices, Procrustes analysis and elliptical Fourier analysis) on classification performance were evaluated. Procrustes analysis and elliptical Fourier analysis perform better than shape indices when single view is considered, but all perform equally well with combined views. A generic content-based image retrieval (CBIR) system that ranks dissimilarity (Procrustes distance) of otolith images was built to search query images without the need for detailed information of side (left or right), aspect (proximal or distal) and direction (positive or negative) of the otolith. Methods for the development of this automated classification system are discussed.