Consensus categorization of cheese based on water activity and pH-A rational approach to systemizing cheese diversity.

Development of science-based interventions in raw milk cheese production is challenging due to the large diversity of production procedures and final products. Without an agreed upon categorization scheme, science-based food safety evaluations and validation of preventive controls would have to be completed separately on each individual cheese product, which is not feasible considering the large diversity of products and the typically small scale of production. Thus, a need exists to systematically group raw milk cheeses into logically agreed upon categories to be used for food safety evaluations. This paper proposes and outlines one such categorization scheme that provides for 30 general categories of cheese. As a base for this systematization and categorization of raw milk cheese, we used Table B of the US Food and Drug Administration's 2013 Food Code, which represents the interaction of pH and water activity for control of vegetative cells and spores in non-heat-treated food. Building on this table, we defined a set of more granular pH and water activity categories to better represent the pH and water activity range of different raw milk cheeses. The resulting categorization scheme was effectively validated using pH and water activity values determined for 273 different cheese samples collected in the marketplace throughout New York State, indicating the distribution of commercially available cheeses among the categories proposed here. This consensus categorization of cheese provides a foundation for a feasible approach to developing science-based solutions to assure compliance of the cheese processors with food safety regulations, such as those required by the US Food Safety Modernization Act. The key purpose of the cheese categorization proposed here is to facilitate product assessment for food safety risks and provide scientifically validated guidance on effective interventions for general cheese categories. Once preventive controls for a given category have been defined, these categories would represent safe havens for cheesemakers, which would allow cheesemakers to safely and legally produce raw milk cheeses that meet appropriate science-based safety requirements (e.g., risk to human health equivalent to pasteurized milk cheeses).

High frequency of contact allergy to gold in patients with endovascular coronary stents.

BACKGROUND: Stent implantation is an effective method for treatment of atherosclerotic disease. Factors predisposing to in-stent restenosis are still largely unknown. Contact allergy to metal ions eluted from the stent has been suggested to be a risk factor. OBJECTIVES: To explore whether there is a possible induction of contact allergy to metals used in stents among patients with a stainless steel stent containing nickel (Ni stent) and patients with a gold-plated stent (Au stent). METHODS: Adults (n = 484) treated with coronary stent implantation participated in the study with patch testing. The study design was retrospective and cross-sectional with no assessment of contact allergy before stenting. Age- and sex-matched patch-tested patients with dermatitis (n = 447) served as controls. RESULTS: Of Au-stented patients, 54 of 146 (37%) were allergic to gold compared with 85 of 447 (19%) controls (P < 0.001). Within the stented population there were no statistically significant differences in contact allergy to gold or nickel between Ni-stented and Au-stented patients. In multivariate models where other risk factors for contact allergy to gold were considered, the Au stent showed a trend towards statistical significance (odds ratio 1.43, 95% confidence interval 0.95-2.16; P = 0.09). CONCLUSIONS: As the frequency of contact allergy to gold is higher in stented patients independent of stent type it suggests a previous sensitization. However, several pieces of circumstantial evidence as well as statistical analysis indicate the possibility of sensitization in the coronary vessel by the Au stent. Ni stents and Au stents should not be ruled out as risk factors for induction of contact allergy to these metals.

[Prevalence of depressive disorders among frail elderly, assessed by psychogeriatricians, general practitioners and geriatricians]. / Praevalens af depressionssygdom blandt svage aeldre, vurderet ved gerontopsykiater, praktiserende laeger og geriater.

UNLABELLED: The prevalence of depressive disorders (D) in 70 years of age or older frail elderly was studied. Two hundred and eleven (81%) recipients of Municipal Home Help Service (frail elderly) in a rural area of Jutland were included and screened by the Geriatric Depression Scale-15 (GDS). If participants had: a) a GDS-score > or = 5 points or/and b) a history of depression, further evaluation was given by: 1) general practitioners (GPs) (implicit criteria), 2) a psycho-geriatrician (ICD-10 criteria), and 3) a geriatrician with the Hamilton Test for Depression. Prevalence rates for D among the evaluators: 15-18%. The diagnostic agreement was only fair. IN CONCLUSION: 18% of the studied population fulfilled the ICD-10 research criteria for depression. The GDS may help GPs in diagnosing depression among frail elderly. False GDS negatives, found among GDS negatives with a history of depression, should be evaluated thoroughly when identifying depression in the target group.

Teleradiology by two different concepts. Technical note.

Two different teleradiology concepts are described. Their advantages, disadvantages and costs are discussed.

Phantom study of chest radiography with storage phosphor, selenium, and film-screen systems.

PURPOSE: Chest radiographs from 3 digital systems--2 based on luminescent phosphors and one on selenium--and a conventional film-screen system were evaluated and compared. MATERIAL AND METHODS: Computed radiography (CR) has for the past years been dominated by a single manufacturer, but now several systems have been marketed. Using a chest phantom and, as test objects, 2 simulated tumours for the lung and mediastinum, respectively, and one object simulating pulmonary lines, a total of 400 exposures were made, 100 on each system. The test objects were placed randomly with a ratio of presence/absence of each object of about 50. Six radiologists participated, 2 residents and 4 staff members. A receiver operating characteristics (ROC) analysis was performed with construction of curves, and the difference between the curves was estimated with a 2-tailed paired t-test. RESULTS AND CONCLUSION: The selenium-based system performed significantly better for pulmonary line detection than all the other systems, and better than one storage phosphor system for the lung "tumour" (p < 0.05), while one storage phosphor system was slightly better than the other in diagnosing all 3 test objects. The score for the film-screen system was only average.

Radiological videoconferencing in Sweden.

For the last four years there has been a videoconferencing link between the Karlskrona hospital and the university hospital of Lund. Because of a need to transmit angiographic films, its use has been gradually expanded to become an everyday routine, used for both elective and emergency examinations. During 1994 and 1995, 1121 cases were examined over the video link. Apart from 156 normal cases all were discussed with surgeons, most at 96 weekly conferences but approximately 50 at conferences taking place as soon as possible after the examination. Assuming that an average of three doctors attended the conferences before the video link was available, this amounts to a saving of 3 x 8 h in travelling time per videoconference. The average salary was 300 SKr/h and train tickets cost a further 400 SKr per person. The cost of the ISDN connection was approximately 1800 SKr/conference. The net gain was thus about 6500 SKr per videoconference, without taking into account the work that could be done with the doctors still in Karlskrona after the conference.

Evaluation of the image quality of ink-jet printed paper copies of digital chest radiographs as compared with film: a receiver operating characteristic study.

Paper copies of digital radiographs printed with the continuous ink-jet technique have proved to be of a high enough quality for demonstration purposes. We present a study on the image quality of ink-jet printed paper copies of digital chest radiographs, based on receiver operating characteristic (ROC) analysis. Eighty-three digital radiographs of a chest phantom with simulated tumors in the mediastinum and right lung, derived from a computed radiography (CR) system were presented in two series of hard copies as ink-jet printed paper copies and as laser recorded film. The images, with a matrix of 1,760 x 2,140 pixels, were printed with a spatial resolution of 10 pixels/mm in the CR film recorder as well as in the ink-jet printer. On film, every image was recorded in two versions, one optimized for the mediastinum and one for the lungs. On paper, only one image was printed; this constituted an effort to optimize both the mediastinum and the lungs. The ink-jet printed images, printed on a matt coated paper, were viewed as on-sight images with reflected light. The examinations were reviewed by six radiologists, and ROC curves were constructed. No significant difference was found between the performance of film and that of ink-jet paper prints. Because the cost for a paper copy is only a tenth of that of film, remarkable cost reductions can be achieved by using the ink jet technique instead. Our results show that further quality studies of ink-jet printed images are worthwhile.

Breast imaging: a comparison of digital luminescence radiographs displayed on TV-monitor and film-screen mammography.

The purpose of this study was to compare the diagnostic accuracy of conventional film-screen mammograms with the corresponding digital luminescence mammograms saved on optical disk and viewed on a 1240-line monitor. One hundred mammograms from 100 patients, including 17 biopsy-proven cancers and one cancer confirmed by cytology, were reviewed. Five radiologists with different mammography experience served as observers, and receiver operating characteristic (ROC) curves were constructed. The result of the monitor interpretation was not inferior to the conventional mammogram interpretation. One observer with vast mammography experience obtained excellent results with a digital interpretation.

Digital luminescence radiography using a chest phantom. Comparison between radiographs displayed on monitor at a workstation and at a personal.

With the introduction of picture and archiving communicating systems an alternative image display for the wards might be a personal computer (PC). The intention with this study was to evaluate the diagnostic image quality of the monitor of a PC compared to that of a workstation. Eighty-five digital radiographs of a chest phantom with simulated tumors in the mediastinum and right lung were saved on optical discs. The examination were reviewed by 4 radiologists on a monitor at a workstation and at a PC, and receiver operating characteristic (ROC) curves were constructed. No significant difference was found between performance of the PC and the workstation.

Demonstration of digital radiographs by means of ink jet-printed paper copies: pilot study.

Different digital medical images have been printed on paper with a continuous ink jet printer, and the quality has been evaluated. The emphasis has been on digital chest radiographs from a computed radiography system. The ink jet printing technique is described as well as the handling of the image data from image source to printer. Different versions of paper prints and viewing conditions were compared to find the optimum alternative. The evaluation has been performed to maximize the quality of the paper images to make them conform with the corresponding film prints and monitor images as much as possible. The continuous ink jet technique offers high-quality prints on paper at a considerably lower cost per copy compared with the cost of a film print. With a future switch-over from diagnosing of digital images on film to diagnosing them on monitors, hard copies for demonstration purposes will occasionally be needed. This need can be filled by ink jet-printed paper copies.

Bedside chest radiography using digital luminescence. A comparison between digital radiographs reviewed on a personal computer and as hard-copies.

The introduction of picture and archiving communicating systems is currently being evaluated in several institutions. We decided, as an intermediate step, to see if image quality after transferral to a personal computer (PC) is sufficient for the diagnostic needs in an intensive care unit. Seventy-five portable digital chest radiographs were studied both as hard-copies and on a monitor after transferral to a PC. Two chest radiologists and one anesthesiologist reviewed the examinations. Our intention was to evaluate if everything that is routinely checked by the anesthesiologist is demonstrable after electronic transfer to a local workstation. We found practically no difference between the performance of monitor and film for the whole material.

Digital luminescence radiography using a chest phantom. Comparison between radiographs displayed on monitor and hard-copy.

Ninety-eight digital radiographs of a chest phantom with simulated tumors in the mediastinum and left lung and a pneumothorax-simulation in the right hemithorax were compared with the corresponding examinations saved on optical disk and viewed on a 1,000-line monitor. The examinations were reviewed by 7 radiologists with different experience, and receiver operating characteristic (ROC) curves were constructed. There was no significant difference between the hard-copy and the monitor results. A significant interobserver difference was seen only with the low attenuating 6 mm "tumor" and then only between the observer with the highest and the one with the lowest scores.

Efficacy of inverted digital luminescence radiography in evaluating chest neoplasms.

Inverted (positive) digital chest radiographs of patients with lung tumors were compared with commonly used (negative) digital images, consisting of one simulated normal and one contrast enhanced image. The first part of the material consisted of 80 patients of whom 40 had tumors and 40 were normal. Five radiologists with different experience reviewed the examinations. From their answers, ROC curves were constructed. The second part of the material consisted of 100 chest phantom examinations with a simulated tumor in the mediastinum (45 examinations) and/or the left lung (46 examinations). In 31 exposures there was no abnormality. These were reviewed by 3 observers and performed as an ROC study as well. There was no statistical difference between the different types of images or between the observers in the 2 studies.

Comparison of iohexol with barium in gastrointestinal studies of infants and children.

This study evaluates iohexol as a contrast agent in the gastrointestinal tract in children. In the first part of the study, iohexol in concentrations of 180 and 300 mg l/ml was compared in double-blind manner with barium. Sixty-four patients were studied. No significant difference in changes of blood pressure and pulse rate was found between the three groups of patients studied. Diarrhea was significantly more common in the children receiving iohexol than in children receiving barium. The diarrhea was not due to previously identified high-risk factors in the children, nor was it due to concurrent medication. When image quality was assessed in each anatomic region of the gastrointestinal tract, fewer nondiagnostic ratings occurred with barium than with iohexol. With barium, fewer ratings of poor mucosal coating and slightly fewer ratings of suboptimal contrast density occurred. The second part of the study was an open evaluation of iohexol 180 mg l/ml in 18 patients in whom barium was clinically contraindicated. Three of 53 assessments were nondiagnostic. Mucosal coating was poor in 6%, and contrast density was suboptimal in 8% of patients. The results of this study indicate that barium is the preferred contrast agent for routine evaluation of the gastrointestinal tract in children. Good-quality images can be obtained, however, with iohexol in concentrations of 180 or 300 mg l/ml, and iohexol is an excellent contrast agent for evaluation of the gastrointestinal tract in those patients in whom barium is relatively or absolutely contraindicated.

Digital luminescence radiography in interstitial lung disease. A receiver operating characteristics (ROC) analysis.

The subtle changes often found in interstitial lung disease can be difficult to evaluate at conventional radiography. In order to define the information obtained with digital radiography, it is particularly important to find out to what extent interstitial lung disease can be observed with this technique. Ninety-one patients, 56 with interstitial lung disease and 35 with normal lungs, were examined both with a digital system and with conventional film-screen technique. The examinations were reviewed independently by 4 radiologists with different experience and receiver operating characteristics (ROC) curves were constructed. The 2 systems were equal in diagnostic performance with no statistic difference between the conventional radiographs, the 2 digital images reviewed together or the 2 digital images reviewed separately. There was a significant difference between the 2 observers with the highest and the one with the lowest score only in the review of digital unsharp mask images, but otherwise no differences statistically. A lower number of false negatives and a higher number of false positives were seen with the digital unsharp mask image, producing a higher sensitivity and lower specificity.

Accuracy of digital radiography using stimulable phosphor for diagnosis of pneumothorax.

To evaluate the efficacy of digitized radiography in diagnosing pneumothorax 78 patients were examined with both the conventional film-screen technique and digital radiography. Of these 78 examinations 40 were normal and in 38 a pneumothorax was found. Four observers with different experience reviewed the films. In an ROC analysis no significant differences were found between the two systems. Between the observers, however, there were slight differences, one of them showing significantly lower specificity.

Assessment of digital chest radiography using stimulable phosphor.

In this pilot study, conventional and digital radiography of the chest was compared in 170 patients. Two digitized radiographs, one frequency modified and one simulating the conventional film-screen combination, and the conventional films were reviewed independently by 5 radiologists with different experience. In spite of the smaller size and lower spatial resolution of the digitized compared with the conventional radiograph, only slight differences were revealed in the observation of different pulmonary and mediastinal changes. Digitized radiography is therefore considered suitable for chest examinations.

Intra-operative digital angiography as a control of the in situ saphenous vein by-pass grafts.

Forty-two patients undergoing in situ saphenous vein by-pass grafting procedures, in two patients bilaterally, were examined intra-operatively with digital subtraction angiography. In 19 (43%) of the examinations the graft and the anastomoses appeared adequate. In 8 cases (18%) significant abnormalities were found, including stenoses (11%), deficient anastomoses (5%) and graft kinking (2%). Remaining arteriovenous fistulas were found in 17 patients (39%). In most cases immediate correction was possible avoiding later re-operation. At follow up 11 of the 44 grafts were occluded, 10 of these during the first five months and of these five during the first week.