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BACKGROUND: The prevalence of overweight and obesity is increasing worldwide at an alarming rate. An Internet-based weight-loss programme has the potential to reach larger numbers of people than traditional face-to-face programmes. A growing body of evidence supports the use of low glycaemic load (GL) diets for weight loss. The present study aimed to investigate the efficacy of an Internet-based weight-loss programme that included foods with a low GL. METHODS: One hundred and three volunteers, with a body mass index (BMI) ≥28 kg m(-2) , enrolled into an Internet weight-loss programme. A dietitian counselled participants over the Internet via weekly interactive chat rooms and monthly e-mails. Participants self-recorded body weight and food intake directly on to the Internet site. Weight, BMI and waist circumference were measured, and dietary data collected, at baseline and 6 months. RESULTS: Seventy participants completed the 6-month weight-loss programme. Among these, mean weight, BMI and waist circumference significantly decreased by 3.5 kg (95% CI = 2.3-4.7), 1.2 kg m(-2) (95% CI = 0.8-1.7) and 4.8 cm (95% CI = 2.8-6.8), of baseline values respectively (P < 0.001). Twenty-five (36%) of the 70 participants lost a clinically significant amount of weight (>5% of initial body weight). CONCLUSIONS: This descriptive study has shown that an Internet-based weight-loss programme with low GL principles can promote weight loss. This type of intervention and approach could be used to enhance other weight-loss strategies.

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We present a novel route for producing a new class of titanium foams for use in biomedical implant applications. These foams are hierarchically porous, with both the traditional large (>300µm) highly interconnected pores and, uniquely, wall struts also containing micron scale (0.5-5µm) interconnected porosities. The fabrication method consists of first producing a porous oxide precursor via a gel casting method, followed by electrochemical reduction to produce a metallic foam. This method offers the unique ability to tailor the porosity at several scales independently, unlike traditional space-holder techniques. Reducing the pressure during foam setting increased the macro-pore size. The intra-strut pore size (and percentage) can be controlled independently of macro-pore size by altering the ceramic loading and sintering temperature during precursor production. Typical properties for an 80% porous Ti foam were a modulus of ∼1GPa, a yield strength of 8MPa and a permeability of 350 Darcies, all of which are in the range required for biomedical implant applications. We also demonstrate that the micron scale intra-strut porosities can be exploited to allow infiltration of bioactive materials using a novel bioactive silica-polymer composite, resulting in a metal-bioactive silica-polymer composite.

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Under load-bearing conditions metal-based foam scaffolds are currently the preferred choice as bone/cartilage implants. In this study X-ray micro-computed tomography was used to discretize the three-dimensional structure of a commercial titanium foam used in spinal fusion devices. Direct finite element modeling, continuum micromechanics and analytical models of the foam were employed to characterize the elasto-plastic deformation behavior. These results were validated against experimental measurements, including ultrasound and monotonic and interrupted compression testing. Interrupted compression tests demonstrated localized collapse of pores unfavorably oriented with respect to the loading direction at many isolated locations, unlike the Ashby model, in which pores collapse row by row. A principal component analysis technique was developed to quantify the pore anisotropy which was then related to the yield stress anisotropy, indicating which isolated pores will collapse first. The Gibson-Ashby model was extended to incorporate this anisotropy by considering an orthorhombic, rather than a tetragonal, unit cell. It is worth noting that the natural bone is highly anisotropic and there is a need to develop and characterize anisotropic implants that mimic bone characteristics.

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The tilapia fish Oreochromis alcalicus grahami from Kenya has adapted to living in waters at pH 10.5 by excreting the end product of nitrogen metabolism as urea rather than as ammonia directly across the gills as occurs in most fish. The level of activity in liver of the first enzyme in the urea cycle pathway, carbamoyl-phosphate synthetase III (CPSase III), is too low to account for the observed high rates of urea excretion. We report here the surprising finding that CPSase III and all other urea cycle enzyme activities are present in muscle of this species at levels more than sufficient to account for the rate of urea excretion; in addition, the basic kinetic properties of the CPSase III appear to be different from those of other known type III CPSases. The sequence of the CPSase III cDNA is reported as well as the finding that glutamine synthetase activity is present in liver but not in muscle. This unusual form of adaptation may have occurred because of the apparent impossibility of packaging the needed amount of urea cycle enzymes in liver.

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The comparative effects of adhesive tape and three semirigid ankle orthoses on ankle functional range of motion were studied on 11 college football athletes. Maximum plantar flexion and maximum dorsiflexion were measured under five conditions to determine functional range of motion. Testing conditions included: control (no supportive device), adhesive tape with moleskin, the Airstirrup "Training" orthosis, the Active Ankle "Trainer" orthosis, and the Ankle Ligament Protector. A 200-Hz video camera was used to record subjects' motions in the sagittal plane while they ran a series of 40-yd sprints. Videotape was analyzed with the Peak Performance Technology Motion Measurement System. Data were analyzed with a Repeated Measures MANOVA. Differences were found among treatments for maximum plantar flexion and functional range of motion. Follow-up analyses indicated that the Ankle Ligament Protector was the only supportive device that was significantly more restrictive than the control. The Airstirrup, Active Ankle, and adhesive tape with moleskin do not significantly affect functional range of motion during running.

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Coexpression of biologically active interleukin 6 (IL-6), an immunoregulator, and hepatitis B virus surface antigen (HBsAg), an immunogen, was obtained using an adenovirus type 7 (Ad7) vector. Two recombinant adenoviruses (re-Ad) containing both the HBsAg and IL6 genes were constructed: one virus was capable of expressing IL6 with its signal peptide (spIL6) (Ad7::spIL6::HBsAg), and the second virus lacked this sequence (Ad7::IL6::HBsAg). A third recombinant contained only HBsAg (Ad7::HBsAg). All three Ad constructs were plaque purified and characterized in the A549 human lung cell line. The growth kinetics of the recombinants were similar to wild-type (wt) Ad7. The production and secretion of HBsAg (p24 and gp27) from cells infected with each re-Ad were at a level greater than 9 micrograms/10(6) cells by 118 h postinfection. Two IL-6 of approx. 24 and 27 kDa were produced and secreted into the culture medium from cells infected with Ad7::spIL6::HBsAg, and maximal accumulation occurred by 92 h p.i. at a level > 260 ng/10(6) cells. One cell-associated IL-6 of approx. 23 kDa was produced from cells infected with Ad7::IL6::HBsAg at a level > 12 ng/10(6) cells. Importantly, the Ad-produced IL-6 were determined to be biologically active by enhancing immunoglobulin production in lymphoblastoid cells. The co-production of IL-6 with HBsAg did not affect growth of these recombinant Ad, immunoreactivity of HBsAg, or the biological activity of IL-6 in tissue culture cells.

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As experience accumulates, previously held beliefs about the risks and dangers of large scale lipoplasty are being challenged. We present our experience with over 300 patients who underwent large scale suctions ranging in volume from 2500 to 8000 cc. We have found that the incidence of postoperative complications does not correlate directly with the volume of fat extracted. Preoperative fluid loading, adequate intraoperative fluid management, and the liberal use of autologous whole blood transfusions appear to reduce the risks of large scale suctions. It is the belief of the author that, when indicated, single stage lipoplasty of greater than 2500 cc is an appropriate alternative to staged procedures, and can be safely undertaken when adequate provisions are made for blood replacement.

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The heat shock response was studied as a model for control of gene expression and protein synthesis in Giardia lamblia. Cultured trophozoites were metabolically labelled with [35S]methionine, and proteins were analysed by SDS-polyacrylamide gel electrophoresis and fluorography. A temperature shift from 37 degrees C to 43 degrees C resulted in the depression of normal protein synthesis, and the enhanced synthesis of four major heat shock proteins of 100, 83, 70 and 30 kDa. This response resembles that seen in other organisms of wide phylogenetic diversity. An examination of the kinetics of induction and recovery from heat shock suggests that the individual heat shock proteins are independently regulated. In vitro translation of messenger RNA isolated from heat shocked cells further indicates that regulation occurs at both transcriptional and translational levels. The response of G. lamblia to other stresses including cysteine deprivation, exposure to oxygen, ethanol, hydrogen peroxide, and the chemotherapeutic drugs metronidazole and quinacrine was also investigated. The induction of two or more of the heat shock proteins was generally observed; however, certain treatments inhibited synthesis of all proteins including heat shock proteins.

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In the superior cervical sympathetic ganglion (SCG) of the rat, a significant amount of morphological and biochemical maturation occurs in the first few postnatal weeks. The specific activity of tyrosine hydroxylase (TH), the rate-limiting enzyme in the synthesis of norepinephrine (NE), increases during this time and is subject to transsynaptic regulation by the preganglionic inputs. In the present study, we examined the normal postnatal development of NE stores in sympathetic neurons and the transsynaptic regulation of this development. NE content undergoes an 8-fold increase from the time of birth, and stabilizes at adult levels at one month. Following neonatal deafferentation, there is a temporary stunting of NE accumulation in sympathetic neurons and a permanent reduction in the activity of TH, whether or not regeneration of the afferents occurs. When regeneration is prevented, the turnover of NE is significantly reduced, while NE levels rise to near normal levels. When regeneration is permitted, however, both the stored amount and turnover of NE attain normal levels. These data suggest that there is a critical period during the first two postnatal weeks when transsynaptic influences from afferents are necessary for the induction of TH in sympathetic neurons. Levels and turnover of transmitter do not have this critical period, but appear to depend solely on the functional integrity of the system.

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Volunteers were asked to guess their blood alcohol level immediately before having their venous level measured by gas chromatography. Thirty-one percent were able to guess to within 20 mg per 100ml of the measured amount. There was a tendency for people to over-estimate if the level was low and to under-estimate the higher values. Blood alcohol concentrations ranged from nil to 295mg per 100ml with both high and low being recorded throughout the evening.

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Postoperative arterial oxygen tension was measured in a group of patients. Unacceptably low levels were found in 32% of the patients and this hypoxaemia persisted in some cases for three days. The results enforce the principle that some patients whould be given prolonged oxygen therapy and this should cease only when blood gas analysis demonstrate the patients ability to maintain a safe PaO2 breathing air.

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Radiological total lung capacity (T.L.C.) was measured preoperatively and postoperatively in a group of patients. A decrease in T.L.C. postoperatively in patients who smoke was demonstrated. The use of radiological T.L.C. in the study of postoperative respiratory dysfunction is suggested.

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