Biomedical subjects

Wendy M Smith

Publications and source records attributed to Wendy M Smith.

6 recordsLinked to original sources

PubMed2004

Systematic review: surveillance systems for early detection of bioterrorism-related diseases.

BACKGROUND: Given the threat of bioterrorism and the increasing availability of electronic data for surveillance, surveillance systems for the early detection of illnesses and syndromes potentially related to bioterrorism have proliferated. PURPOSE: To critically evaluate the potential utility of existing surveillance systems for illnesses and syndromes related to bioterrorism. DATA SOURCES: Databases of peer-reviewed articles (for example, MEDLINE for articles published from January 1985 to April 2002) and Web sites of relevant government and nongovernment agencies. STUDY SELECTION: Reports that described or evaluated systems for collecting, analyzing, or presenting surveillance data for bioterrorism-related illnesses or syndromes. DATA EXTRACTION: From each included article, the authors abstracted information about the type of surveillance data collected; method of collection, analysis, and presentation of surveillance data; and outcomes of evaluations of the system. DATA SYNTHESIS: 17,510 article citations and 8088 government and nongovernmental Web sites were reviewed. From these, the authors included 115 systems that collect various surveillance reports, including 9 syndromic surveillance systems, 20 systems collecting bioterrorism detector data, 13 systems collecting influenza-related data, and 23 systems collecting laboratory and antimicrobial resistance data. Only the systems collecting syndromic surveillance data and detection system data were designed, at least in part, for bioterrorism preparedness applications. Syndromic surveillance systems have been deployed for both event-based and continuous bioterrorism surveillance. Few surveillance systems have been comprehensively evaluated. Only 3 systems have had both sensitivity and specificity evaluated. LIMITATIONS: Data from some existing surveillance systems (particularly those developed by the military) may not be publicly available. CONCLUSIONS: Few surveillance systems have been specifically designed for collecting and analyzing data for the early detection of a bioterrorist event. Because current evaluations of surveillance systems for detecting bioterrorism and emerging infections are insufficient to characterize the timeliness or sensitivity and specificity, clinical and public health decision making based on these systems may be compromised.

Bioterrorism↗

PubMed2004

Evaluating detection and diagnostic decision support systems for bioterrorism response.

We evaluated the usefulness of detection systems and diagnostic decision support systems for bioterrorism response. We performed a systematic review by searching relevant databases (e.g., MEDLINE) and Web sites for reports of detection systems and diagnostic decision support systems that could be used during bioterrorism responses. We reviewed over 24,000 citations and identified 55 detection systems and 23 diagnostic decision support systems. Only 35 systems have been evaluated: 4 reported both sensitivity and specificity, 13 were compared to a reference standard, and 31 were evaluated for their timeliness. Most evaluations of detection systems and some evaluations of diagnostic systems for bioterrorism responses are critically deficient. Because false-positive and false-negative rates are unknown for most systems, decision making on the basis of these systems is seriously compromised. We describe a framework for the design of future evaluations of such systems.

Bioterrorism↗

PubMed2004

Splenic rupture: a rare presentation of pancreatic carcinoma.

CONTEXT: Splenic rupture secondary to solid malignancy is an infrequent complication that usually occurs late in the progression of a previously diagnosed cancer. In rare instances, splenic rupture precipitates the discovery of an unsuspected pancreatic carcinoma. We report 2 cases of adenocarcinoma of the pancreas in which the patients presented with splenic rupture. OBJECTIVES: To review the clinicopathologic features of splenic rupture due to pancreatic carcinoma and to increase awareness of malignancy as a possible etiology for atraumatic splenic rupture. DESIGN: We reviewed the clinical and pathologic data from 2 patients. A literature search was conducted to identify previous reports of splenic rupture associated with pancreatic cancer. We summarized the characteristics of the earlier cases and compared them with those of our patients. RESULTS: We found only 4 previous reports of splenic rupture preceding the diagnosis of pancreatic cancer. In 3 of these cases, the pancreatic carcinoma grossly invaded the spleen at the time of resection. In contrast, malignancy was not suspected as the etiology of the rupture in our patients until histologic examination of the resected spleen revealed carcinoma. CONCLUSION: Splenic rupture is an unusual presentation of cancer of the pancreas, and to our knowledge only 4 cases have been reported previously in the literature. Although an underlying malignancy is relatively rare, spleens resected for atraumatic rupture should be carefully examined for possible neoplastic etiologies.

Female↗

PubMed2002

APC-dependent suppression of colon carcinogenesis by PPARgamma.

Activation of PPARgamma by synthetic ligands, such as thiazolidinediones, stimulates adipogenesis and improves insulin sensitivity. Although thiazolidinediones represent a major therapy for type 2 diabetes, conflicting studies showing that these agents can increase or decrease colonic tumors in mice have raised concerns about the role of PPARgamma in colon cancer. To analyze critically the role of this receptor, we have used mice heterozygous for Ppargamma with both chemical and genetic models of this malignancy. Heterozygous loss of PPARgamma causes an increase in beta-catenin levels and a greater incidence of colon cancer when animals are treated with azoxymethane. However, mice with preexisting damage to Apc, a regulator of beta-catenin, develop tumors in a manner insensitive to the status of PPARgamma. These data show that PPARgamma can suppress beta-catenin levels and colon carcinogenesis but only before damage to the APC/beta-catenin pathway. This finding suggests a potentially important use for PPARgamma ligands as chemopreventative agents in colon cancer.

Animals↗

PubMed2002

Germ-line mutations in nonsyndromic pheochromocytoma.

BACKGROUND: The group of susceptibility genes for pheochromocytoma that included the proto-oncogene RET (associated with multiple endocrine neoplasia type 2 [MEN-2]) and the tumor-suppressor gene VHL (associated with von Hippel-Lindau disease) now also encompasses the newly identified genes for succinate dehydrogenase subunit D (SDHD) and succinate dehydrogenase subunit B (SDHB), which predispose carriers to pheochromocytomas and glomus tumors. We used molecular tools to classify a large cohort of patients with pheochromocytoma with respect to the presence or absence of mutations of one of these four genes and to investigate the relevance of genetic analyses to clinical practice. METHODS: Peripheral blood from unrelated, consenting registry patients with pheochromocytoma was tested for mutations of RET, VHL, SDHD, and SDHB. Clinical data at first presentation and follow-up were evaluated. RESULTS: Among 271 patients who presented with nonsyndromic pheochromocytoma and without a family history of the disease, 66 (24 percent) were found to have mutations (mean age, 25 years; 32 men and 34 women). Of these 66, 30 had mutations of VHL, 13 of RET, 11 of SDHD, and 12 of SDHB. Younger age, multifocal tumors, and extraadrenal tumors were significantly associated with the presence of a mutation. However, among the 66 patients who were positive for mutations, only 21 had multifocal pheochromocytoma. Twenty-three (35 percent) presented after the age of 30 years, and 17 (8 percent) after the age of 40. Sixty-one (92 percent) of the patients with mutations were identified solely by molecular testing of VHL, RET, SDHD, and SDHB; these patients had no associated signs and symptoms at presentation. CONCLUSIONS: Almost one fourth of patients with apparently sporadic pheochromocytoma may be carriers of mutations; routine analysis for mutations of RET, VHL, SDHD, and SDHB is indicated to identify pheochromocytoma-associated syndromes that would otherwise be missed.

Adolescent↗

PubMedDate not supplied

A conceptual framework for evaluating information technologies and decision support systems for bioterrorism preparedness and response.

OBJECTIVES: The authors sought to develop a conceptual framework for evaluating whether existing information technologies and decision support systems (IT/DSSs) would assist the key decisions faced by clinicians and public health officials preparing for and responding to bioterrorism. METHODS: They reviewed reports of natural and bioterrorism related infectious outbreaks, bioterrorism preparedness exercises, and advice from experts to identify the key decisions, tasks, and information needs of clinicians and public health officials during a bioterrorism response. The authors used task decomposition to identify the subtasks and data requirements of IT/DSSs designed to facilitate a bioterrorism response. They used the results of the task decomposition to develop evaluation criteria for IT/DSSs for bioterrorism preparedness. They then applied these evaluation criteria to 341 reports of 217 existing IT/DSSs that could be used to support a bioterrorism response. MAIN RESULTS: In response to bioterrorism, clinicians must make decisions in 4 critical domains (diagnosis, management, prevention, and reporting to public health), and public health officials must make decisions in 4 other domains (interpretation of bioterrorism surveillance data, outbreak investigation, outbreak control, and communication). The time horizons and utility functions for these decisions differ. From the task decomposition, the authors identified critical subtasks for each of the 8 decisions. For example, interpretation of diagnostic tests is an important subtask of diagnostic decision making that requires an understanding of the tests' sensitivity and specificity. Therefore, an evaluation criterion applied to reports of diagnostic IT/DSSs for bioterrorism asked whether the reports described the systems' sensitivity and specificity. Of the 217 existing IT/DSSs that could be used to respond to bioterrorism, 79 studies evaluated 58 systems for at least 1 performance metric. CONCLUSIONS: The authors identified 8 key decisions that clinicians and public health officials must make in response to bioterrorism. When applying the evaluation system to 217 currently available IT/DSSs that could potentially support the decisions of clinicians and public health officials, the authors found that the literature provides little information about the accuracy of these systems.

Bioterrorism↗