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J Baillie

Publications and source records attributed to J Baillie.

At least 19 recordsLinked to original sources

Endoscopic ultrasound and computer tomography are inaccurate methods of classifying cystic pancreatic lesions.

BACKGROUND: Despite advances in imaging modalities, preoperative diagnosis of pancreatic cystic lesions remains difficult. AIM: To assess the accuracy of endoscopic ultrasound and computer tomography to preoperatively distinguish benign from potentially malignant and malignant pancreatic cystic lesions. METHODS: Photograph series obtained from endoscopic ultrasound examinations of 66 patients with cystic pancreatic lesions were blindly reviewed by three endoscopic ultrasonographers. Forty-one of those 66 patients also underwent a computer tomography scan at our institution, which was blindly reviewed by a single radiologist. Computer tomography and endoscopic ultrasound classification into benign and malignant and potentially malignant pancreatic cystic lesions was correlated with the final diagnosis, which was established by surgical pathology (n = 43), diagnostic fine needle aspiration (n = 13) or follow-up imaging (n = 10). Interobserver agreement was measured using kappa statistics. RESULTS: Endoscopic ultrasound classification by the three examiners into benign versus malignant or potentially malignant cystic lesions was correct in 65-67%. Interobserver agreement was 50%. Kappa values for pairs of endoscopic ultrasound examiners were 0.16, 0.43 and 0.53. Computer tomography classification was correct in 71% and in agreement with the endoscopic ultrasound classification in 56-61% (kappa 0.12 to 0.27). CONCLUSIONS: Endoscopic ultrasound and computer tomography cannot accurately distinguish between benign pancreatic cystic lesions and malignant or potentially malignant ones. There is poor-to-modest interobserver agreement in classifying these lesions.

Adult↗

Using Red List Indices to measure progress towards the 2010 target and beyond.

The World Conservation Union (IUCN) Red List is widely recognized as the most authoritative and objective system for classifying species by their risk of extinction. Red List Indices (RLIs) illustrate the relative rate at which a particular set of species change in overall threat status (i.e. projected relative extinction-risk), based on population and range size and trends as quantified by Red List categories. RLIs can be calculated for any representative set of species that has been fully assessed at least twice. They are based on the number of species in each Red List category, and the number changing categories between assessments as a result of genuine improvement or deterioration in status. RLIs show a fairly coarse level of resolution, but for fully assessed taxonomic groups they are highly representative, being based on information from a high proportion of species worldwide. The RLI for the world's birds shows that that their overall threat status has deteriorated steadily during the years 1988-2004 in all biogeographic realms and ecosystems. A preliminary RLI for amphibians for 1980-2004 shows similar rates of decline. RLIs are in development for other groups. In addition, a sampled index is being developed, based on a stratified sample of species from all major taxonomic groups, realms and ecosystems. This will provide extinction-risk trends that are more representative of all biodiversity.

Amphibians↗

Measuring the fate of plant diversity: towards a foundation for future monitoring and opportunities for urgent action.

Vascular plants are often considered to be among the better known large groups of organisms, but gaps in the available baseline data are extensive, and recent estimates of total known (described) seed plant species range from 200000 to 422000. Of these, global assessments of conservation status using International Union for the Conservation of Nature (IUCN) categories and criteria are available for only approximately 10000 species. In response to recommendations from the Conference of the Parties to the Convention on Biological Diversity to develop biodiversity indicators based on changes in the status of threatened species, and trends in the abundance and distribution of selected species, we examine how existing data, in combination with limited new data collection, can be used to maximum effect. We argue that future work should produce Red List Indices based on a representative subset of plant species so that the limited resources currently available are directed towards redressing taxonomic and geographical biases apparent in existing datasets. Sampling the data held in the world's major herbaria, in combination with Geographical Information Systems techniques, can produce preliminary conservation assessments and help to direct selective survey work using existing field networks to verify distributions and gather population data. Such data can also be used to backcast threats and potential distributions through time. We outline an approach that could result in: (i) preliminary assessments of the conservation status of tens of thousands of species not previously assessed, (ii) significant enhancements in the coverage and representation of plant species on the IUCN Red List, and (iii) repeat and/or retrospective assessments for a significant proportion of these. This would result in more robust Sampled Red List Indices that can be defended as more representative of plant diversity as a whole; and eventually, comprehensive assessments at species level for one or more major families of angiosperms. The combined results would allow scientifically defensible generalizations about the current status of plant diversity by 2010 as well as tentative comments on trends. Together with other efforts already underway, this approach would establish a firmer basis for ongoing monitoring of the status of plant diversity beyond 2010 and a basis for comparison with the trend data available for vertebrates.

Biodiversity↗

Complications of pancreaticoduodenectomy after neoadjuvant chemoradiation in patients with and without preoperative biliary drainage.

BACKGROUND: It has been suggested that preoperative biliary drainage increases the risk of infectious complications of pancreaticoduodenectomy. AIMS: The aim of this study was to assess complications related to biliary stents/drains and postoperative morbidity in patients undergoing neoadjuvant chemoradiotherapy for periampullary cancer. PATIENTS: One hundred and eighty-four patients with periampullary neoplasms were prospectively selected for neoadjuvant external beam radiation therapy and 5-fluorouracil-based chemotherapy between 1995 and 2002. METHODS: The data were retrospectively completed and analysed with respect to biliary drainage, efficacy and complications of endoscopic biliary stents and postoperative morbidity. Patients who had undergone a surgical biliary bypass were excluded. RESULTS: Data were completed in 168 patients. One hundred and nineteen patients were treated with endoscopic biliary stents, 18 patients had a percutaneous biliary drain and 31 patients did not require biliary drainage. Hospitalisation for stent-related complications was necessary in 15% of the patients with endoscopic biliary stents. Seventy-two patients underwent pancreaticoduodenectomy. There was no significant difference in the rate of wound infections, intra-abdominal abscesses and overall complications between the groups with and without preoperative biliary drainage. CONCLUSIONS: Postoperative infectious complications are common in patients both with and without preoperative biliary drainage. A statistically significant difference in complication rates was not observed between these groups.

Adult↗

Yield of endoscopic ultrasound-guided fine-needle aspiration of bile duct lesions.

BACKGROUND AND STUDY AIMS: It is still difficult to differentiate reliably between benign and malignant biliary tract lesions. Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) has added to the diagnostic power of EUS for other gastrointestinal tumors. A retrospective analysis of experience with FNA sampling of bile duct lesions was therefore carried out. PATIENTS AND METHODS: All EUS-FNA procedures for bile duct masses or strictures were analyzed at our tertiary referral center from May 2000 through October 2002. Data for EUS findings, the results of EUS-FNA, and tissue sampling at surgery were included. EUS-FNA procedures were carried out using a 22-gauge needle. An experienced cytopathologist was present during FNA in all but three cases. Clinical follow-up details were recorded when available for patients in whom a suitable diagnostic gold standard was not available for comparison. RESULTS: A total of 35 patients underwent EUS-FNA of bile duct lesions during the study period. There were no complications. Data for EUS-FNA of bile duct masses or strictures and tissue obtained at surgery were available for 23 patients. If positive cytology at surgical pathology is taken as the gold standard, EUS-FNA has a diagnostic yield for cancer of 100 % (if atypia/inconclusive findings in the FNA sample are regarded as benign). Eleven patients had a definite malignancy on surgical pathology. Of these 11 patients, five had a finding of malignancy on EUS-FNA, giving a sensitivity of 45 % (if FNA cytology reported as atypia/inconclusive is regarded as benign). Twelve patients had findings of no malignancy from tissue obtained at surgery. Of these 12 patients, nine had benign pathology and three had atypia/inconclusive findings in the EUS-FNA sample (specificity of 100 % if atypia/inconclusive findings are considered benign). A further 12 patients did not have surgical specimens for comparison with EUS-FNA results. Four patients had definite findings of malignancy on EUS-FNA alone, and one patient had FNA findings suspicious for malignancy. Seven patients had negative or equivocal EUS-FNA results. These 12 patients are described but excluded from further analysis, as a gold standard was not available for comparison. However, clinical follow-up data were available for eight of these 12 patients, and in each case the follow-up findings were compatible with previous benign or malignant EUS-FNA findings. CONCLUSIONS: The practice of EUS-FNA has improved the diagnostic yield of EUS. These results suggest that it is a safe and useful procedure for investigating biliary masses or strictures that have hitherto caused considerable diagnostic confusion, especially in patients with negative brush cytology findings. The possibility of false-negative findings remains, but core biopsy needles may improve the situation. The results of further studies are awaited.

Aged↗

Pancreatitis.

In the past decade, our understanding of the genetic basis, pathogenesis, and natural history of pancreatitis has grown strikingly. In severe acute pancreatitis, intensive medical support and non-surgical intervention for complications keeps patients alive; surgical drainage (necrosectomy) is reserved for patients with infected necrosis for whom supportive measures have failed. Enteral feeding has largely replaced the parenteral route; controversy remains with respect to use of prophylactic antibiotics. Although gene therapy for chronic pancreatitis is years away, our understanding of the roles of gene mutations in hereditary and sporadic pancreatitis offers tantalising clues about the disorder's pathogenesis. The division between acute and chronic pancreatitis has always been blurred: now, genetics of the disorder suggest a continuous range of disease rather than two separate entities. With recognition of pancreatic intraepithelial neoplasia, we see that chronic pancreatitis is a premalignant disorder in some patients. Magnetic resonance cholangiopancreatography and endoscopic ultrasound are destined to replace endoscopic retrograde cholangiopancreatography for many diagnostic indications in pancreatic disease.

Acute Disease↗

Colonoscopy or barium enema for population colorectal cancer screening?

There is good evidence from faecal occult blood testing trials that detection and removal of non-advanced colorectal neoplasms can achieve a reduction in colorectal cancer mortality. Both colonoscopy and barium enema have potential advantages and disadvantages if implemented for population screening. The relative merits of each are discussed.

Barium Sulfate↗

Human cytomegalovirus infection inhibits tumor necrosis factor alpha (TNF-alpha) signaling by targeting the 55-kilodalton TNF-alpha receptor.

Infection with human cytomegalovirus (HCMV) results in complex interactions between viral and cellular factors which perturb many cellular functions. HCMV is known to target the cell cycle, cellular transcription, and immunoregulation, and it is believed that this optimizes the cellular environment for viral DNA replication during productive infection or during carriage in the latently infected host. Here, we show that HCMV infection also prevents external signaling to the cell by disrupting the function of TNFRI, the 55-kDa receptor for tumor necrosis factor alpha (TNF-alpha), one of the receptors for a potent cytokine involved in eliciting a wide spectrum of cellular responses, including antiviral responses. HCMV infection of fully permissive differentiated monocytic cell lines and U373 cells resulted in a reduction in cell surface expression of TNFRI. The reduction appeared to be due to relocalization of TNFRI from the cell surface and was reflected in the elimination of TNF-alpha-induced Jun kinase activity. Analysis of specific phases of infection suggested that viral early gene products were responsible for this relocalization. However, a mutant HCMV in which all viral gene products known to be involved in down-regulation of major histocompatibility complex (MHC) class I were deleted still resulted in relocalization of TNFRI. Consequently, TNFRI relocalization by HCMV appears to be mediated by a novel viral early function not involved in down-regulation of cell surface MHC class I expression. We suggest that upon infection, HCMV isolates the cell from host-mediated signals, forcing the cell to respond only to virus-specific signals which optimize the cell for virus production and effect proviral responses from bystander cells.

Cell Line↗

Predictors of successful clinical and laboratory outcomes in patients with primary sclerosing cholangitis undergoing endoscopic retrograde cholangiopancreatography.

UNLABELLED: Endoscopic retrograde cholangiopancreatography (ERCP) in patients with primary sclerosing cholangitis (PSC) can be a challenging and sometimes gratifying opportunity for therapeutic intervention. Although there often appears to be initial radiological improvement after ERCP, the benefit as measured by serial estimations of subsequent liver enzymes is questionable. The fluctuating course of the inflammatory process makes the interpretation of serology even more difficult. OBJECTIVES: To document and compare the liver profile and clinical status of patients before and after diagnostic and therapeutic ERCP; to determine predictors of clinical and laboratory success in patients with PSC; and to assess the complication rate of diagnostic and therapeutic ERCP in these patients. METHODS: All patients with PSC who underwent ERCP at the authors' medical centres between January 6, 1987 and January 12, 1998 were identified using a computerized database. Presenting symptoms, liver enzymes (aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase) and bilirubin were recorded before ERCP. Clinical success was defined as resolution of the presenting symptoms. Laboratory success was defined as improvement in two of three liver enzymes by at least 50%, or resolution of jaundice. RESULTS: One hundred four patients underwent 204 ERCPs of which 56 ERCPs were diagnostic. Clinical improvement was seen in 35% of the patients after diagnostic ERCP and in 70% after therapeutic procedures (chi 2=18.4, P=0.001). Laboratory improvement was seen in 35% of patients undergoing diagnostic ERCP and in 52% of the patients undergoing therapeutic ERCP (P=0.04). The reductions in liver enzymes were significant in both the diagnostic and therapeutic groups. Serum bilirubin level decreased significantly in the therapeutic ERCP group only. In a univariate analysis, patients with common bile duct strictures, any dominant stricture and those who underwent a therapeutic procedure were most likely to have clinical and laboratory improvement. In multivariable logistic regression, the presence of a dominant stricture, endoscopic therapy and high serum bilirubin were all independent predictors of a successful clinical outcome. There was no difference in total complication rates (18% versus 14%) when comparing the diagnostic and therapeutic ERCP groups. However, all seven severe complications occurred in the therapeutic ERCP group. CONCLUSIONS: First, in PSC, clinical and laboratory improvement is more common in patients undergoing therapeutic ERCP than diagnostic ERCP. Second, aspartate aminotransferase, alanine aminotransferase and alkaline phosphatase improve following both diagnostic and therapeutic ERCP, and should therefore not be relied upon to determine the success of the procedure. Third, bilirubin levels decreased in the therapeutic group but remained unchanged in the diagnostic group, suggesting that the serum bilirubin level may be a more sensitive indicator of successful therapeutic intervention than transaminases. Fourth, common bile duct strictures, dominant strictures and bilirubin levels are important variables in determining the success of an ERCP in PSC. Finally, complication rates after therapeutic ERCP are similar to those after diagnostic ERCP in PSC patients. However, severe complications occur more commonly in the therapeutic group.

Adult↗