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Current strategies for cell-based screening generally focus on the development of highly specific assays, which require an understanding of the nature of the signaling molecules and cellular pathways involved. In contrast, changes in temperature of cells provides a measure of altered cellular metabolism that is not stimulus specific and hence could have widespread applications in cell-based screening of receptor agonists and antagonists, as well as in the assessment of toxicity of new lead compounds. Consequently, we have developed a micromachined nanocalorimetric biological sensor using a small number of isolated living cells integrated within a subnanoliter format, which is capable of detecting 13 nW of generated power from the cells, upon exposure to a chemical or pharmaceutical stimulus. The sensor comprises a 10-junction gold and nickel thermopile, integrated on a silicon chip which was back-etched to span a 800-nm-thick membrane of silicon nitride. The thin-film membrane, which supported the sensing junctions of the thermoelectric transducer, gave the system a temperature resolution of 0.125 mK, a low heat capacity of 1.2 nJ m[K.sup.-1], and a rapid (unfiltered) response time of 12 ms. The application of the system in ultra-low-volume cell-based assays could provide a rapid endogenous screen. It offers important additional advantages over existing methods in that it is generic in nature, it does not require the use of recombinant cell lines or of detailed assay development, and finally, it can enable the use of primary cell lines or tissue biopsies.

* Context.--Measuring variation in clinician test ordering behavior for patients with similar indications is an important focus for quality management and cost containment. Objective.--To obtain information from physicians and nonphysicians regarding their test-ordering behavior and their knowledge of test performance characteristics for diagnostic tests used to work up patients with lung lesions suspicious for cancer. Design.--A self-administered, voluntary, anonymous questionnaire was distributed to 452 multiple-specialty physicians and 500 nonphysicians in academic and private practice in Pennsylvania, Iowa, and North Carolina. Respondents indicated their estimates of test sensitivities for multiple tests used in the diagnosis of lung lesions and provided their test selection strategy for case simulations of patients with solitary lung lesions. Data were analyzed using descriptive statistics and the [chi square] test. Results.--The response rate was 11.2%. Both physicians and nonphysicians tended to underestimate the sensitivities of all minimally invasive tests, with the greatest underestimations reported for sputum cytology and transthoracic fine-needle aspiration biopsy. There was marked variation in sequential test selection for all the case simulations and no association between respondent perception of test sensitivity and their selection of first diagnostic test. Overall, the most frequently chosen first diagnostic test was bronchoscopy. Conclusions.--Physicians and nonphysicians tend to underestimate the performance of diagnostic tests used to evaluate solitary lung lesions. However, their misperceptions do not appear to explain the wide variation in test-ordering behavior for patients with lung lesions suspicious for cancer. (Arch Pathol Lab Med. 2002;126;19-27), The diagnostic assessment of patients who have a solitary, radiographically detected lung lesion is common. (1) In many patients, the clinical suspicion of malignancy is high, and an estimated 169 [...]

* Objectives.--To determine baseline parameters for routine outpatient test turnaround time (TAT), to identify influential factors, and to study the impact of managed care on this testing. Method.--Using forms supplied by the College of American Pathologists Q-Probes program, laboratories conducted a self-directed study of routine outpatient TATs over a 4-week period. Data requested included various times of day associated with the collection, laboratory receipt, and result verification of specimens, as well as details on the drawing location and ordering and delivery methods for up to 3 tests, namely, a complete blood cell count (CBC), biochemical profile, or thyrotropin test. For the CBC, an indication was requested if a manual differential was performed. Additionally, practice-related questions were asked, including several about whether the laboratory was associated with a managed care organization (MCO). The main outcome measures included the components of the TAT process and related factors. Participants.--Six hundred nineteen laboratories from those enrolled in the 1997 College of American Pathologists Q-Probes program. Results.--Data were submitted by 614 participants, most US hospitals, and represented 30240 CBCs, 25 683 biochemical profiles, and 14801 thyrotropins. Collection to verification TATs increased for specimens received later in the day for all analytes, but the magnitude of the increase was greatest for thyrotropin. Collection to laboratory receipt TAT was similar for all analytes, but the time and distribution increased with time of day. Testing time (receipt to verification) was similar for the CBC and biochemical profile, but was greatly increased for thyrotropin. Most participants tested the CBC and the biochemical profile as they arrived, but many delayed testing for thyrotropin. Most (70%) outpatient specimens were collected within the institution; only about 10% came from local physicians' offices. A median 46.7% of hospital testing involved outpatients. Only 10% of laboratories operated under an MCO; these laboratories reported a median of 45% of specimens coming from their MCO. Being associated with an MCO increased TAT for the CBC and biochemical profile. Conclusions.--Outpatient testing comprises about half of all hospital testing, yet systems are not optimized. Preanalytic TAT increases during the day, which indicates increasing delays in the collection and transport stages. Imposition of a test schedule on thyrotropin results in a delay pattern that is very different from the CBC and biochemical profile, which are tested on arrival. A laboratory's association with an MCO had a weak impact on TAT. (Arch Pathol Lab Med. 2002;126;11-18), Evaluating clinical laboratory specimen turnaround time (TAT) is a critical component of laboratory quality assurance programs. (1) A review by Valenstein (2) and extensive investigations by the College of American [...]

Although bacterial stool pathogens and parasitic organisms such as Salmonella, Shigella, or Campylobacter do not usually cause hospital-acquired diarrhea, it remains common practice in many institutions to order routine stool cultures and ova and parasite (O & P) examinations on all patients with symptoms. The degree to which these tests are inappropriately ordered was studied by examining the relation between test results from stool cultures, O & P examinations, and Clostridium difficile toxin assays and the time at which these tests were ordered after hospital admission. During a three-year period, only one of 191 positive stool cultures and none of the positive O & P examinations were obtained from patients whose stool specimens were obtained at least three days after admission. As expected, most positive results were not related to hospital-acquired diarrhea. However, analysis of laboratory workload for a one-year period showed that half of more than 3,000 stool specimens received each year are from patients hospitalized for three days or more. Twenty-five percent of the stool samples were positive for C. difficile, regardless of the patients' admission status, indicating that testing for C. difficile toxin is warranted. The results demonstrate that eliminating routine stool culture and O & P examinations on hospitalized patients would reduce hospital and patient costs without affecting patient care and possibly would result in a nationwide cost savings of $20 to $30 million per year. (Consumer Summary produced by Reliance Medical Information, Inc.)

Abstract Aim-To determine whether the introduction of a standard reporting proforma has led to an improvement in the completeness of histopathology reports for breast cancer excision specimens. Methods--A standard reporting [...]

Abstract Aims--There is a perception among histopathologists that specimens are often received without adequate clinical details. This is the first study to determine the adequacy of information provided when histopathological [...]

Abstract Aim--At present, the diagnosis of muscular dystrophy is made by means of immunohistochemistry on frozen sections. The aim of this study was to develop a sensitive and reproducible immunohistochemical [...]

Abstract Whole mount sections of the prostate are widely used in many laboratories. Macrocryosections of the gland; that is, whole mount frozen sections of the prostate from radical prostatectomies represent [...]

* Context.--For practitioners deploying store-and-forward telepathology systems, optimization methods such as image compression need to be studied. Objective.--To determine if Joint Photographic Expert Group (JPG or JPEG) compression, a lossy image compression algorithm, negatively affects the accuracy of diagnosis in telepathology. Design.--Double-blind, randomized, controlled trial. Setting.--University-based pathology departments. Participants.--Resident and staff pathologists at the University of Illinois, Chicago, and University of Cincinnati, Cincinnati, Ohio. Intervention.--Compression of raw images using the JPEG algorithm. Main Outcome Measures.--Image acceptability, accuracy of diagnosis, confidence level of pathologist, image quality. Results.--There was no statistically significant difference in the diagnostic accuracy between noncompressed (bit map) and compressed (JPG) images. There were also no differences in the acceptability, confidence level, and perception of image quality. Additionally, rater experience did not significantly correlate with degree of accuracy. Conclusions.--For providers practicing telepathology, JPG image compression does not negatively affect the accuracy and confidence level of diagnosis. The acceptability and quality of images were also not affected. (Arch Pathol Lab Med. 2000;124:1653-1656), A Randomized Clinical Trial Medical specialties that rely on images to formulate a diagnosis lend themselves to the store-and-forward method of telemedicine. With this method, images are captured and then [...]

A Basis for Checklists This protocol is intended to assist pathologists in providing clinically useful and relevant information as a result of the examination of surgical specimens. Use of this [...]

The desire to eliminate poliovirus depends on a global system of laboratories that can identify the virus in tissue samples. The World Health Organization's Global Laboratory Network consists of 67 national labs, 14 regional reference labs, and six specialized reference labs. These labs must meet accreditation standards by the end of 1997. Recent tests indicate that many of the national labs were able to identify a single virus strain but had difficulty when the sample contained more than one strain of virus. However, such samples would then be sent to the regional labs, which have a better track record in processing these samples.