A putative target for the anti-colorectal cancer action of nonsteroidal anti-inflammatory drugs is the inducible isoform of cyclooxygenase (COX), COX-2. COX-2 is expressed within intestinal adenomas ...in murine polyposis models, but expression has been poorly characterized in human colorectal neoplasms. Therefore, we investigated the localization of the COX-2 protein in human sporadic colorectal adenomas. Immunohistochemistry for COX-2 and CD68 (a tissue macrophage marker) was performed on formalin-fixed, paraffin-embedded (
n = 52. and frozen, acetone-fixed (
n = 6) sections of human sporadic colorectal adenomas. Forty of 52 (77%. formalin-fixed adenomas expressed immunoreactive COX-2. COX-2 was localized to superficial interstitial macrophages in 39 cases (75%) and to deep interstitial macrophages in 9 cases (17%). COX-2 staining of dysplastic epithelial cells was observed in 15 cases (29%). A logistic regression analysis identified the adenoma site (
P = 0.012) and histological type (
P = 0.001) as independent predictors of superficial macrophage COX-2 expression. There was no relationship between the number of macrophages within an adenoma and macrophage COX-2 expression. These results indicate that COX-2 is expressed predominantly by interstitial macrophages within human sporadic colorectal adenomas. If COX-2 does indeed play a role in the early stages of colorectal carcinogenesis in man, these data suggest COX-2-mediated paracrine signaling between the macrophages and epithelial cells within adenomas.
Ultrawideband radar is commonly used in the frequency range of 50-500 MHz to detect buried pipes at a depth of about 1-2 m depending on the soil characteristics. The typical feature used to locate ...the pipes is the hyperbolic pattern of the time of flight generated by a linear scan of the antenna above the surface. When the pipes are close together, the hyperbolas overlap, and a straightforward least squares fit is not possible. The Hough transform provides one possible solution. This paper extends the Hough transform by introducing a weighting factor depending on the differentials of the unknown parameters with respect to the experimental errors, namely, the probe position error and the time-of-flight error. This enables optimally placed sets of data pairs to be given greater weight than "ill-conditioned" sets, as for example when all data pairs lie near one end of the arc. The result is a decrease in the background amplitude with respect to the maximum of the peaks in the Hough accumulator space. It is shown that this improvement persists even when many arcs are present. A mathematical analysis with analytical results is given for the case of four unknowns: pipe radius R, pipe center position (Y, Z), and soil propagation velocity V. The results are presented through simulations introducing controlled uncertainties in the probe position, the time of flight, and its bin size. The simulations demonstrate the correlations that occur between the radius, depth, and velocity for given experimental uncertainties.
Objectives To examine patterns of referral, management and survival of men with prostate cancer, and to document changes over time.
Patients and methods All men registered with prostate cancer in ...1988 and 1993 were identified from the Scottish Cancer Registry. Data were ed according to standard definitions from the available medical records of 930 men in 1988 and 1355 in 1993.
Results There was limited evidence of multidisciplinary care, with only 8% of patients in 1988 being managed by both a urologist and a clinical oncologist within a year of diagnosis, increasing to 13% in 1993. Only a small proportion of patients were managed by clinical oncologists during the first year of care (14% in 1988 and 20% in 1993). Documentation of thorough staging information was poor, with a T stage being recorded in <30% of cases in both years. Documentation of metastatic status increased from 53% to 63% between 1988 and 1993, paralleling an increase in the use of bone scans. The proportion of cases with pathological grading obtained at diagnosis increased from 63% in 1988 to 68% by 1993. The use of PSA testing and core biopsies increased between the years while the use of transurethral prostatectomy decreased. More patients received radical radiotherapy within a year of diagnosis in 1993 than 1988, increasing from 6% to 9%, and more radical prostatectomies were also undertaken (0.2% to 2.3%). Nonetheless, most patients (81% in 1993) with no documented evidence of metastases received no active intervention (radical radiotherapy, radical prostatectomy, or ‘watchful waiting’). The survival at 5 years increased nonsignificantly from 34% for the 1988 cohort to 38% for the 1993 cohort.
Conclusion This audit reveals considerable inconsistency in the management of men with prostate cancer in Scotland. Against a background of controversy about numerous aspects of the management of this disease, the need for a multidisciplinary approach, comprehensive staging and appropriate documentation is highlighted.
Peripheral nerve dysfunction (PND) was found in as many as 43% of our patients with human T-cell lymphotropic virus type I (HTLV-I)-associated myelopathy (HAM/TSP). To evaluate the PND further we ...biopsied the sural nerve in 6 patients. The histological features were varying degrees of demyelination, remyelination, axonal atrophy and degeneration, and perineurial fibrosis. "Globule" or "sausage" formation was prominent in two of the specimens. Inflammatory infiltrates were absent. No deposits of IgG, IgM, IgA, or complement were detected in the biopsies. No viral antigen or proviral DNA was detected. It is proposed that the PND and the histological findings noted are part of HTLV-I-associated disease and not an unrelated disorder. The pathogenesis of the PND remains unclear. There was no evidence of direct viral infection. The histological findings could represent primary changes induced by viral-triggered release of soluble factors, such as cytokines or secondary changes to more proximal disease, e.g., root involvement.
Background
Simulation‐based training assumes that skills are directly transferable to the patient‐based setting, but few studies have correlated simulated performance with surgical performance.
...Methods
A systematic search strategy was undertaken to find studies published since the last systematic review, published in 2007. Inclusion of articles was determined using a predetermined protocol, independent assessment by two reviewers and a final consensus decision. Studies that reported on the use of surgical simulation‐based training and assessed the transferability of the acquired skills to a patient‐based setting were included.
Results
Twenty‐seven randomized clinical trials and seven non‐randomized comparative studies were included. Fourteen studies investigated laparoscopic procedures, 13 endoscopic procedures and seven other procedures. These studies provided strong evidence that participants who reached proficiency in simulation‐based training performed better in the patient‐based setting than their counterparts who did not have simulation‐based training. Simulation‐based training was equally as effective as patient‐based training for colonoscopy, laparoscopic camera navigation and endoscopic sinus surgery in the patient‐based setting.
Conclusion
These studies strengthen the evidence that simulation‐based training, as part of a structured programme and incorporating predetermined proficiency levels, results in skills transfer to the operative setting.
Simulation‐based training needs wider adoption
The interaction of many-body systems with intense light pulses may lead to novel emergent phenomena far from equilibrium. Recent discoveries, such as the optical enhancement of the critical ...temperature in certain superconductors and the photo-stabilization of hidden phases, have turned this field into an important research frontier. Here, we demonstrate nonthermal charge-density-wave (CDW) order at electronic temperatures far greater than the thermodynamic transition temperature. Using time- and angle-resolved photoemission spectroscopy and time-resolved X-ray diffraction, we investigate the electronic and structural order parameters of an ultrafast photoinduced CDW-to-metal transition. Tracking the dynamical CDW recovery as a function of electronic temperature reveals a behaviour markedly different from equilibrium, which we attribute to the suppression of lattice fluctuations in the transient nonthermal phonon distribution. A complete description of the system's coherent and incoherent order-parameter dynamics is given by a time-dependent Ginzburg-Landau framework, providing access to the transient potential energy surfaces.
Unexplained spastic myelopathy in black (Zulu) patients, similar to that seen in the tropics, has previously been described from Natal, South Africa. Following reports linking the human T cell ...lymphotropic virus type I (HTLV-I) to spastic myelopathy, we undertook a prospective and retrospective search for HTLV-I antibodies in 36 patients who were labelled as having unexplained myelopathy; 24 (66%) were positive and HTLV-I was isolated from 4 out of the 6 patients whose peripheral blood lymphocytes were cultured. Eighteen (75%) gave a short history (less than 6 months). There was a female preponderance (71%), spinothalamic dysfunction was common (55%) and as many as half were severely disabled (50% wheelchair bound). Routine laboratory studies showed no specific trends apart from hypergammaglobulinaemia and CSF pleocytosis (greater than 5 cells/microliter in 66% of patients). The total CSF protein was raised (greater than 0.4 g/l) in 45% of patients. The IgG index was greater than 0.7 in 15 of 19 patients. Conventional myelography did not show any specific abnormalities. Computer assisted myelography was undertaken in 22 patients; 3 showed arachnoiditis and 2 spinal cord atrophy. Periventricular lucencies were seen in 1 of 10 patients who had computed tomography of the head. Nerve conduction studies demonstrated abnormalities in 46% of the patients indicating that subclinical peripheral nerve dysfunction was common. Visual evoked responses were abnormal in only 1 patient but brainstem auditory evoked response studies showed some abnormality in 42% of the patients. The finding of HTLV-I antibodies in a significant number, and the isolation of HTLV-I from the blood in 6 of our black patients with noncompressive myelopathy, represents a substantial clinical advance. Future studies should define more clearly the role of the virus in this disorder.
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