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James P Smith

Publications and source records attributed to James P Smith.

At least 19 recordsLinked to original sources
PubMed2006

Survival of patients with stage I lung cancer detected on CT screening.

BACKGROUND: The outcome among patients with clinical stage I cancer that is detected on annual screening using spiral computed tomography (CT) is unknown. METHODS: In a large collaborative study, we screened 31,567 asymptomatic persons at risk for lung cancer using low-dose CT from 1993 through 2005, and from 1994 through 2005, 27,456 repeated screenings were performed 7 to 18 months after the previous screening. We estimated the 10-year lung-cancer-specific survival rate among participants with clinical stage I lung cancer that was detected on CT screening and diagnosed by biopsy, regardless of the type of treatment received, and among those who underwent surgical resection of clinical stage I cancer within 1 month. A pathology panel reviewed the surgical specimens obtained from participants who underwent resection. RESULTS: Screening resulted in a diagnosis of lung cancer in 484 participants. Of these participants, 412 (85%) had clinical stage I lung cancer, and the estimated 10-year survival rate was 88% in this subgroup (95% confidence interval [CI], 84 to 91). Among the 302 participants with clinical stage I cancer who underwent surgical resection within 1 month after diagnosis, the survival rate was 92% (95% CI, 88 to 95). The 8 participants with clinical stage I cancer who did not receive treatment died within 5 years after diagnosis. CONCLUSIONS: Annual spiral CT screening can detect lung cancer that is curable.

Adult↗
PubMed2006

Disease and disadvantage in the United States and in England.

CONTEXT: The United States spends considerably more money on health care than the United Kingdom, but whether that translates to better health outcomes is unknown. OBJECTIVE: To assess the relative heath status of older individuals in England and the United States, especially how their health status varies by important indicators of socioeconomic position. DESIGN, SETTING, AND PARTICIPANTS: We analyzed representative samples of residents aged 55 to 64 years from both countries using 2002 data from the US Health and Retirement Survey (n = 4386) and the English Longitudinal Study of Aging (n = 3681), which were designed to have directly comparable measures of health, income, and education. This analysis is supplemented by samples of those aged 40 to 70 years from the 1999-2002 waves of National Health and Nutrition Examination Survey (n = 2097) and the 2003 wave of the Health Survey for England (n = 5526). These surveys contain extensive and comparable biological disease markers on respondents, which are used to determine whether differential propensities to report illness can explain these health differences. To ensure that health differences are not solely due to health issues in the black or Latino populations in the United States, the analysis is limited to non-Hispanic whites in both countries. MAIN OUTCOME MEASURE: Self-reported prevalence rates of several chronic diseases related to diabetes and heart disease, adjusted for age and health behavior risk factors, were compared between the 2 countries and across education and income classes within each country. RESULTS: The US population in late middle age is less healthy than the equivalent British population for diabetes, hypertension, heart disease, myocardial infarction, stroke, lung disease, and cancer. Within each country, there exists a pronounced negative socioeconomic status (SES) gradient with self-reported disease so that health disparities are largest at the bottom of the education or income variants of the SES hierarchy. This conclusion is generally robust to control for a standard set of behavioral risk factors, including smoking, overweight, obesity, and alcohol drinking, which explain very little of these health differences. These differences between countries or across SES groups within each country are not due to biases in self-reported disease because biological markers of disease exhibit exactly the same patterns. To illustrate, among those aged 55 to 64 years, diabetes prevalence is twice as high in the United States and only one fifth of this difference can be explained by a common set of risk factors. Similarly, among middle-aged adults, mean levels of C-reactive protein are 20% higher in the United States compared with England and mean high-density lipoprotein cholesterol levels are 14% lower. These differences are not solely driven by the bottom of the SES distribution. In many diseases, the top of the SES distribution is less healthy in the United States as well. CONCLUSION: Based on self-reported illnesses and biological markers of disease, US residents are much less healthy than their English counterparts and these differences exist at all points of the SES distribution.

Aged↗
PubMed2006

Semi-empirical power-law scaling of new infection rate to model epidemic dynamics with inhomogeneous mixing.

The expected number of new infections per day per infectious person during an epidemic has been found to exhibit power-law scaling with respect to the susceptible fraction of the population. This is in contrast to the linear scaling assumed in traditional epidemiologic modeling. Based on simulated epidemic dynamics in synthetic populations representing Los Angeles, Chicago, and Portland, we find city-dependent scaling exponents in the range of 1.7-2.06. This scaling arises from variations in the strength, duration, and number of contacts per person. Implementation of power-law scaling of the new infection rate is quite simple for SIR, SEIR, and histogram-based epidemic models. Treatment of the effects of the social contact structure through this power-law formulation leads to significantly lower predictions of final epidemic size than the traditional linear formulation.

Chicago↗
PubMed2006

CT screening for lung cancer: the value of short-term CT follow-up.

BACKGROUND: Although CT screening for lung cancer results in a diagnosis of stage I > 80% of the time, benign noncalcified nodules are also found. We recognized that some nodules appeared to represent infectious bronchopneumonia or other inflammatory processes, as they resolved on follow-up CT, sometimes after antibiotic therapy. To determine the extent to which short-term CT radiographic follow-up might shorten the workup of nodules, we reviewed our experience with baseline and annual repeat CT screenings performed subsequent to the original Early Lung Cancer Action Project series. METHODS: The initial CT of 1,968 consecutive baseline and 2,343 annual repeat screenings performed from 1999 to 2002 was reviewed. We identified all those recommended for antibiotics on the initial CT who had a follow-up CT within 2 months and determined whether the nodule(s) resolved, decreased in size, remained unchanged, or grew. We then determined whether further follow-up resulted in a diagnosis of cancer. RESULTS: At baseline, among the 41 individuals who had follow-up CT within 2 months of the initial CT, 12 patients (29%) had complete or partial resolution; none of them subsequently received a diagnosis of lung cancer. On annual repeat screening, among the 39 individuals who had follow-up CT within 2 months of the initial CT, 29 patients (74%) had complete or partial resolution; none of them subsequently received a diagnosis of lung cancer. Among the 29 patients with nodules at baseline that were unchanged or grew, a total of 15 cancers were subsequently diagnosed; among the 10 patients on annual repeat scanning, there were 2 cancers. CONCLUSIONS: In asymptomatic individuals undergoing CT screening for lung cancer, short-term follow-up CT within 2 months with or without antibiotics may circumvent the need for further evaluation in some individuals, particularly on annual repeat screening.

Anti-Bacterial Agents↗
PubMed2005

A rapid chemiluminescent slot blot immunoassay for the detection and quantification of Clostridium botulinum neurotoxin type E, in cultures.

A simple, rapid, cost-effective in vitro slot blot immunoassay was developed for the detection and quantification of botulinum neurotoxin type E (BoNT/E) in cultures. Culture supernatants of 36 strains of clostridia, including 12 strains of Clostridium botulinum type E, 12 strains of other C. botulinum neurotoxin serotypes, and 12 strains of other clostridial species were tested. Samples containing BoNT/E were detected using affinity-purified polyclonal rabbit antisera prepared against BoNT/E with subsequent detection of secondary antibodies using chemiluminescence. All strains of C. botulinum type E tested positive, while all non C. botulinum type E strains tested negative. The sensitivity of the slot blot immunoassay for detection of BoNT/E was approximately four mouse lethal doses (MLD). The intensity of chemiluminescence was directly correlated with the concentration of BoNT/E up to 128 MLD, allowing quantification of BoNT/E between 4 and 128 MLD. The slot blot immunoassay was compared to the mouse bioassay for detection of BoNT/E using cultures derived from fish samples inoculated with C. botulinum type E, and cultures derived from naturally contaminated environmental samples. A total of 120 primary enrichment cultures derived from fish samples, of which 103 were inoculated with C. botulinum type E, and 17 were uninoculated controls, were assayed. Of the 103 primary enrichment cultures derived from inoculated fish samples, all were positive by mouse bioassay, while 94 were also positive by slot blot immunoassay, resulting in a 7.5% false-negative rate. All 17 primary enrichment cultures derived from the uninoculated fish samples were negative by both mouse bioassay and slot blot immunoassay. A total of twenty-six primary enrichment cultures derived from environmental samples were tested by mouse bioassay and slot blot immunoassay. Of 13 primary enrichment cultures positive by mouse bioassay, 12 were also positive by slot blot immunoassay, resulting in a 3.8% false-negative rate. All 13 primary enrichment cultures that tested negative by mouse bioassay also tested negative by slot blot immunoassay. The slot blot immunoassay could be used routinely as a positive screen for BoNT/E in primary enrichment cultures, and could be used as a replacement for the mouse bioassay for pure cultures.

Animal Testing Alternatives↗
PubMed2004

Effects of mastic resin and its essential oil on the growth of proteolytic Clostridium botulinum.

Studies were done to determine the effect of mastic resin and its essential oil, alone and in conjunction with ethanol, on the growth of proteolytic strains of Clostridium botulinum in media, and on neurotoxin production in challenge studies with English-style crumpets. Preliminary studies, using a spot-on-the-lawn method, indicated that high levels of mastic resin in ethanol ( approximately 8% w/w) were required for complete inhibition of all strains of C. botulinum tested, but mastic resin in ethanol had a greater anti-botulinal effect than ethanol alone. However, only low levels of mastic oil ( approximately 0.3% v/v) were required for inhibition of proteolytic strains of C. botulinum. Both studies showed a strain specific inhibition, with C. botulinum type A strains being more sensitive to mastic resin and its essential oil than type B strains. However, mastic resin in ethanol proved to be more effective when used as a vapor phase inhibitor applied to cotton pads and placed inside inoculated plates than when added directly to media. While both mastic resin and its essential oil inhibited the growth of proteolytic strains of C. botulinum in vitro, they failed to inhibit neurotoxin production in challenge studies with C. botulinum in English-style crumpets.

Botulinum Toxins↗
PubMed2004

SFG coming of age.

Explore the source record for details and available documents.

Biomedical Engineering↗
PubMed2004

CT screening for lung cancer: suspiciousness of nodules according to size on baseline scans.

PURPOSE: To assess the frequency with which a particular, possibly optimal work-up of noncalcified nodules less than 5.0 mm in diameter identified on initial computed tomographic (CT) images at baseline screening leads to a diagnosis of malignancy prior to first annual repeat screening, compared with a possibly optimal work-up of larger nodules. MATERIALS AND METHODS: Two series of baseline CT screenings in high-risk people were retrospectively reviewed. The first series (n = 1,000) was performed in 1993-1998; the second (n = 1,897), in 1999-2002. In each series, cases in which the largest noncalcified nodule detected was less than 5.0 mm in diameter and those in which it was 5.0-9 mm were reviewed to determine whether diagnostic work-up prior to first annual repeat screening showed or would have shown nodule growth and led or would have led to a diagnosis based on biopsy or surgical specimens. RESULTS: The frequency with which malignancy was or could have been diagnosed when the largest noncalcified nodule was less than 5.0 mm in diameter was 0 of 378, whereas when the largest noncalcified nodule was 5.0-9 mm in diameter, the frequency was 13 or 14 of 238. If persons with only nodules smaller than 5.0 mm had merely been referred for first annual repeat screening without immediate further work-up, the referrals for such work-up would have been reduced by 54% (from 817 [28%] to 385 [13%] of 2,897). CONCLUSION: In modern CT screening for lung cancer at baseline, detected noncalcified nodules smaller than 5.0 mm in diameter do not justify immediate work-up but only annual repeat screening to determine whether interim growth has occurred.

Adult↗
PubMed2004

Hypertension management: special considerations in chronic kidney disease patients.

It has been estimated that approximately 11% of the US adult population has chronic kidney disease (CKD), and it has been demonstrated that the prevalence of hypertension rises significantly as renal function declines. Even mild CKD significantly increases mortality risk, and cardiovascular disease remains the main cause of death among these patients. Although CKD patients have generally been excluded from trials testing the effect of lowering blood pressure on cardiovascular outcomes, guidelines suggest lowering blood pressure in hopes of reducing cardiovascular mortality and slowing the progression of renal disease. The preferred antihypertensive agents among these patients are drugs that block the renin-angiotensin system. In most hypertensive CKD patients, however, multiple agents are necessary to reach blood pressure targets. In general, diuretics and calcium channel blockers are added subsequently as adjunctive therapy. Hopefully, with increased recognition of the unique aspects of treating hypertension in this population, end-stage renal disease and cardiovascular morbidity and mortality will be delayed or avoided in the millions of patients with CKD.

Antihypertensive Agents↗
PubMed2004

Shelf life and safety concerns of bakery products--a review.

Bakery products are an important part of a balanced diet and, today, a wide variety of such products can be found on supermarket shelves. This includes unsweetened goods (bread, rolls, buns, crumpets, muffins and bagels), sweet goods (pancakes, doughnuts, waffles and cookies) and filled goods (fruit and meat pies, sausage rolls, pastries, sandwiches, cream cakes, pizza and quiche). However, bakery products, like many processed foods, are subject to physical, chemical and microbiological spoilage. While physical and chemical spoilage limits the shelf life of low and intermediate moisture bakery products, microbiological spoilage by bacteria, yeast and molds is the concern in high moisture products i.e., products with a water activity (a(w)) > 0.85. Furthermore, several bakery products also have been implicated infoodborne illnesses involving Salmonella spp., Listeria monoctyogenes and Bacillus cereus, while Clostridium botulinum is a concern in high moisture bakery products packaged under modified atmospheres. This extensive review is divided into two parts. Part I focuses on the spoilage concerns of low, intermediate and high moisture bakery products while Part II focuses on the safety concerns of high moisture bakery products only. In both parts, traditional and novel methods of food preservation that can be used by the bakery industry to extend the shelf life and enhance the safety of products are discussed in detail.

Animals↗
PubMed2004

Managing the small pulmonary nodule discovered by CT.

OBJECTIVES: To review the Early Lung Cancer Action Project experience and the medical literature from 1993 to 2003 on detection of the small, noncalcified pulmonary nodule by CT in order to formulate a management algorithm for these nodules. DESIGN: Prospective noncomparative study of smokers without prior malignancy and a review of the medical literature of CT screening of lung cancer. INTERVENTIONS: Chest CT and, where appropriate, CT observation for nodule growth, antibiotics, CT-guided fine-needle aspiration (FNA) biopsy, fiberoptic bronchoscopy, and video-assisted thoracoscopic surgery (VATS). RESULTS: The following factors influence the probability of malignancy in a CT-detected, small, noncalcified pulmonary nodule: size, change in size, age, smoking history, density, number of nodules, gender, circumstance of the CT, spirometry, occupational history, and endemic granulomatous disease. The two diagnostic techniques most useful in evaluating the CT-detected, small, noncalcified nodule are short-term observation of nodule growth by CT and CT-guided FNA. Due to small nodule size and the frequent finding of nonsolid or part-solid nodules, positron emission tomography, fiberoptic bronchoscopy, and VATS were less useful. CONCLUSIONS: Pulmonologists are frequently asked to evaluate the CT-detected, small, noncalcified nodule invisible on standard chest radiography. Immediate biopsy is justified if the likelihood of cancer is high, but if that likelihood is low or intermediate, a period of observation by CT is appropriate. VATS or thoracotomy are rarely necessary for a diagnosis of lung cancer in the CT-detected small pulmonary nodule.

Adult↗
PubMed2003

Overdiagnosis in chest radiographic screening for lung carcinoma: frequency.

BACKGROUND: The pattern of results in the Mayo Lung Project (MLP), which is the basis for the prevailing recommendations against radiographic screening for lung carcinoma, has led to the assertion that up to 50% of the diagnosed cases of early-stage disease in that trial may have represented overdiagnosed, indolent cases. This finding suggests the possibility of such a high frequency of overdiagnosis in chest radiographic lung carcinoma screening in general. In the current study, the authors analyzed data from the MLP and its counterpart study at Memorial Sloan-Kettering Cancer Center (MSK) to estimate the frequency of overdiagnosis in these studies. METHODS: For the cases diagnosed as Stage I in the MLP and the MSK studies, the doubling times of tumor volumes were calculated. The calculations were based on size measurements recorded by the original investigators from chest radiographs taken during the course of each study. RESULTS: The median doubling times were 101 days in the MLP and 144 days in the MSK, times that are somewhat shorter than those reported in published series of adenocarcinoma cases diagnosed outside screening, and only 5% had doubling times exceeding 400 days. CONCLUSIONS: The hypothesis that early-stage lung tumors diagnosed on chest radiography during lung carcinoma screening may frequently be overdiagnosed, indolent cases needs to be rejected.

Adenocarcinoma↗