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BACKGROUND: Bariatric surgery can provide efficient weight loss and improvement in obesity-related co-morbidities in adults. Laparoscopic adjustable gastric banding (LAGB) comprised 30.3% of all bariatric procedures between 2009 and 2010 in the UK. This review evaluates the level 1 evidence for change in co-morbidities, quality of life (QoL) and weight provided by LAGB compared with other bariatric procedures. METHOD: Systematic literature search of MEDLINE, EMBASE and CENTRAL (1988 to May 2011) was performed. Only randomised controlled trials (RCTs) were included. Studies with non-surgical comparators, open gastric banding procedures or adolescent participants were excluded. Primary outcome was change in co-morbidities. Secondary outcomes included QoL, weight loss, complications, operation time and length of stay. RESULTS: Five RCTs met the inclusion criteria. Vertical banded gastroplasty, sleeve gastrectomy and gastric bypass were compared to LAGB. Co-morbidities were reported in two studies and QoL in one. LAGB was comparable to other procedures for both of these outcomes. All five trials showed LABG to be effective in weight loss, however all comparative procedures resulted in greater weight loss. Operative time and length of hospital stay were significantly shorter with LAGB. Short-term complications were found to be consistently lower in the LAGB group. Evidence was divided with respect to long-term complications. CONCLUSION: Co-morbidities and QoL are poorly reported and showed no difference between LAGB and other bariatric procedures. Evidence suggests that LAGB is not the most effective surgical procedure to reduce weight. LAGB is associated with lower early complications and shorter operative time and length of stay, and therefore may be preferable to patients.

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The architecture of the pod wall and dehiscence zone (DZ) was studied in populations of a resynthesized, shatter-resistant, oilseed rape line, DK142, and the commercial cultivar Apex. The dimensions of the pod wall and its component tissues were significantly larger in DK142. However, the variation in the pod architecture of Apex, DK142 and F2 populations derived from crosses of DK142 and Apex was found to have little or no role in pod shatter. By contrast, variation in the dimensions of the DZ characters correlated strongly and positively with shatter resistance. The size of the main vascular bundle (MVBV) of DK142 as it exited the valve and joined the vascular tissue of the replum was, on average, 60% larger than in Apex, the DZ was 40% wider and there was a high preponderance of vascular tissue other than the MVBV. The variation in the size of the MVBV accounted for much of the variation in shatter resistance of all populations, including shatter-susceptible Apex. The DZ width was also found to be important in explaining the limited range of shatter values in Apex, but in populations of DK142 and F2, where the amount of vascular intrusion into the DZ was much greater, the variation in DZ width was not important. The importance of the vascular tissue to shatter resistance was further highlighted by a novel microfracture test (MFT). By contrast, no significant difference between DK142 and Apex in the ease of separation of the thin-walled DZ cells was detected using the MFT.

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Skin is a complex three-dimensional structure of cells, collagen fibres and other proteins. However most mechanical analyses treat skin as a two-dimensional membrane, neglecting the through thickness structure. In this paper we investigate through thickness reorientation of collagen fibres. The mode of deformation of skin is also considered. For modelling purposes deformation is usually assumed to be affine. This assumption was tested by constructing a simple geometrical, affine deformation model to predict the through thickness reorientation of collagen fibres, from their initial through thickness angle and the measured deformations of skin samples during compression. The measured reorientation of collagen fibres was found to be very variable, however the average reorientations were consistent with the predictions of the model, with the inclusion of a systematic error. The variation in the reorientation of individual fibres can be explained by the variations in the structure at a micrometre scale. The systematic deviation of reorientations from the model predictions can be explained by a non-affine relationship between the collagen fibres and ground substance at a micrometre scale. However, non-affine deformations at a micrometre scale caused by irregularities of structure are likely to average out at a millimetre scale, because at this level material is evenly distributed.

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BACKGROUND: Some benefits of laparoscopic (LC) and minilaparotomy (MC) cholecystectomy may reflect attenuation of the acute phase response. The authors examined components of this response. METHODS: Patients were randomized to LC (n = 11) or MC (n = 11). C-reactive protein (CRP), alpha-1-antitrypsin (AAT), retinol-binding protein (RBP), transferrin, and albumin were measured preoperatively and on postoperative days 1, 2, 4, and 7. Interleukin-1 receptor antagonist (IL-1ra), IL-6, and tumor necrosis factor (TNF-alpha) were measured more frequently perioperatively. Peak expiratory flow rate, forced expiratory volume in 1 second, and forced vital capacity were measured daily. RESULTS: The IL-6 increase was more persistent and marked in the MC patients from hour 8 to day 7 postoperatively (P < 0.05). Alterations in CRP, AAT, and albumin were similar. Postoperative deficits of respiratory function correlated with the magnitude of acute phase protein alteration. CONCLUSIONS: Minimal access surgery induces an acute phase response that is less prominent after a laparoscopic technique.

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BACKGROUND: Trauma, whether accidental or surgically induced, is known to cause significant modulation of the cell-mediated immune response. Minimal access surgery (MAS) has been shown to improve postoperative recovery and enhance rehabilitation. The degree of immunosuppression resulting from two MAS techniques was studied and compared by measuring the circulating T lymphocyte and natural killer (NK) cell subsets. METHOD: This investigation was a randomized prospective study of patients admitted to the Professorial Surgical Unit, Aberdeen Royal Infirmary for elective cholecystectomy. Two methods of MAS were studied-laparoscopy and minilaparotomy. RESULTS: Laparoscopy was found to cause significantly less reduction in the number of cells expressing T lymphocyte phenotypic surface markers (CD2, CD3, CD8, CD4:CD8 ratio), activation markers (CD71 and HLA-DR), and NK cell subsets (CD11b, CD16, CD56 and CD57), when compared with the minilaparotomy technique. CONCLUSIONS: These data show that host defences are less suppressed after laparoscopic cholecystectomy, and this may have important implications for the use of laparoscopic techniques in major surgical resections, especially for malignant disease.

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BACKGROUND: Dietary supplementation with L-arginine enhances natural cytotoxicity in peripheral blood lymphocytes but its effect on infiltrating lymphoreticular cells within a tumour microenvironment is unknown. The effects of dietary supplementation with L-arginine on tumour-infiltrating lymphocytes (TILs) in patients with colorectal cancer were evaluated. METHODS: Eighteen patients received either a standard hospital diet (controls) or a standard diet supplemented with 30 g per day of L-arginine for 3 days before surgery. Tumour biopsies were taken at surgery and lymphocyte subsets (CD antigens) and macrophages examined immunohistochemically. RESULTS: Tumours from patients receiving L-arginine contained increased numbers of specific cell subsets within the tumour which expressed CD16 (P = 0.004) and CD56 (P = 0.001) surface markers, when compared with tumours from control patients. There were no differences in the total number of T and B cells, T helper and T suppressor cells. CONCLUSION: Dietary supplementation with L-arginine significantly alter the spectrum of TILs in human colorectal cancers in vivo. These findings have important implications for new strategies in anticancer treatment.

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A series of 30 cases of male breast cancer in the North-East of Scotland is reviewed. The aims of the study were to document clinico-pathological and immunocytochemical features (available for 25) of these patients and to establish which factors could predict prognosis. Tumours were studied for the expression of oestrogen receptors (ERs), the oestrogen-dependent proteins pS2 and cathepsin D, the oncoprotein products of c-erb-B2 and the p53 tumour-suppressor-gene derived protein. Clinico-pathological features documented were in agreement with those reported by other authors. The overall 5-year survival was 53%. Tumour grade and lymph-node status influenced prognosis. In this series, 64% of the tumours expressed ERs, 50% pS2, 46% cathepsin D, 42% the c-erb-B2 transmembrane oncoprotein and 54% p53. In contrast to female breast cancer, the presence of either substantial amounts of ERs or the oestrogen-dependent protein pS2 correlated with poorer prognosis in males. This correlation has not previously been documented.

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Intrathoracic metastases occur in 30-40% of patients with malignant disease. In this group 6-8% have lymphangitis carcinomatosa. This review examines the pathogenesis, investigation and treatment of lymphangitis carcinomatosa. The 40-49 years age group is most commonly affected. In 46% of patients respiratory symptoms are the initial presentation of the underlying carcinoma. The most common underlying primary tumours are breast (33%), stomach (29%) and lung cancers (17%). Approximately 50% die within 3 months of their first respiratory symptoms but those with a prostatic primary carcinoma may have good remission with adjuvant hormonal therapy.

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Fifteen patients with locally advanced breast cancers were studied using the radiopharmaceutical 2-deoxy-2-[18F]-fluoro-D-glucose (FDG) with positron emission tomography (PET). Five patients were sequentially imaged before and after two pulses of chemotherapy. In 14 of 15 tumours increased uptake of FDG was observed which correlated with the clinical site of the tumour. The PET images were compared with the mammographic and ultrasonomammographic appearances of the tumours in selected patients. In two patients with normal mammograms PET imaging detected the tumour and in a further four patients, with suspicious but not conclusively malignant mammographic changes, a well-defined area of increased FDG uptake was demonstrated by PET. In all five sequentially imaged tumours, following chemotherapy, there was a decrease of the FDG tumour: normal breast uptake ratio. In four patients who completed a full chemotherapeutic course this change preceded a pathological response of their tumours. These findings suggest that this technique may be of benefit in imaging carcinomas in the breasts of pre-menopausal women which may appear dense on mammography and moreover, that sequential imaging may have a role in the prediction, at an early stage, of the response of locally advanced carcinomas to chemotherapy.

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High sensitivity detection of O(2) in the near infrared with short external cavity (SXC) AlGaAs semiconductor diode lasers is reported. The mode control provided by the SXC enhances the performance of these diode lasers by allowing a number of single laser modes (up to ten) to be individually selected and continuously scanned over extended frequency intervals. At a constant laser heat sink temperature, this provides nearly complete spectral coverage of up to approximately 40 cm(-1) for overlapping modes. When using second harmonic detection techniques, these SXC controlled lasers were found to provide high sensitivity detection of O(2) at atmospheric pressure. A minimum detectable absorbance of approximately 4 x 10(-6) has been achieved with a SNR of 1. The stability of these laser systems has also allowed the continuous monitoring of an absorption signal over extended time intervals. Absorbances of 1 x 10(-2) have been continuously monitored for durations of up to 15 h with an rms uncertainty of +/-6 x 10(-5). These results are reproducible for measurements made on all the laser modes that could be selected with the SXC.

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An integrated waveguide-detector coupler (IWDC), in which a controlled fraction of the optical power in a waveguide is selectively coupled to a detector element, has been investigated. The device structure consists of a rib waveguide formed from a sputtered Corning 7059 glass film on an oxidized silicon substrate. A photoconductive detector is fabricated on the same substrate, and the degree of coupling is controlled by tapering the SiO(2) cladding layer thickness in the region between the electrodes and by varying the interaction length. Couplers with cladding layer thicknesses ranging from 0.15 to 0.80 microm in the detector interaction region were measured to have coupling values from 400 to 1500 dB/cm for TE modes and to 5800 dB/cm for TM modes, in good agreement with theory. The first integrated optoelectronic 2 x 2 switching matrix using IWDCs as switching cross-points has been demonstrated. We have shown that the passive power splitting in the integrated switch is nearly the ideal 50%.