[Assessment of teleradiology patients in a major regional hospital]. / Charakterisierung teleradiologisch untersuchter Patienten an einem Krankenhaus der Schwerpunktversorgung.

PURPOSE: To evaluate teleradiology examinations regarding the most frequently requested exams and examined body regions. Additionally, the frequency of pathological changes depending on the examined region and clinical situation as well as the time profile for requesting teleradiology (daytime, day of the week) were analyzed. MATERIALS AND METHODS: A retrospective analysis of all consecutive teleradiology exams in 2018 that were reported in the radiology department of a major regional hospital and scanned in three referring primary health care institutions regarding clinical history, working diagnosis and requested body region was performed. Additionally, the date and time of the examination were analyzed. RESULTS: A total of 1207 CT (computer tomography) scans that were reported as part of the teleradiology agreement were included. The most frequently requested examination was a cranial CT (77.9%) with 14.6% pathological findings, followed by abdominal CT (14%) with 63.9% pathological changes, spine/extremities (8.8%) with 50% pathological changes and CT of the chest (7.9%) with 53.7% abnormal scans. Most teleradiology requests were referred on weekends between 8 am and 4 pm, followed by 4 pm to 6 pm on weekdays. The smallest number of scans was requested between 2 am and 4 am. CONCLUSION: Most teleradiology CT requests focus on brain examinations, followed by abdominal CT, CT of the spine and extremities and CT chest. Most cranial CTs do not show an acute pathology, while abdominal CTs had the highest rate of pathological findings.

Time domain measures of inter-channel EEG correlations: a comparison of linear, nonparametric and nonlinear measures.

Correlations between ten-channel EEGs obtained from thirteen healthy adult participants were investigated. Signals were obtained in two behavioral states: eyes open no task and eyes closed no task. Four time domain measures were compared: Pearson product moment correlation, Spearman rank order correlation, Kendall rank order correlation and mutual information. The psychophysiological utility of each measure was assessed by determining its ability to discriminate between conditions. The sensitivity to epoch length was assessed by repeating calculations with 1, 2, 3, …, 8 s epochs. The robustness to noise was assessed by performing calculations with noise corrupted versions of the original signals (SNRs of 0, 5 and 10 dB). Three results were obtained in these calculations. First, mutual information effectively discriminated between states with less data. Pearson, Spearman and Kendall failed to discriminate between states with a 1 s epoch, while a statistically significant separation was obtained with mutual information. Second, at all epoch durations tested, the measure of between-state discrimination was greater for mutual information. Third, discrimination based on mutual information was more robust to noise. The limitations of this study are discussed. Further comparisons should be made with frequency domain measures, with measures constructed with embedded data and with the maximal information coefficient.

[Medical and legal aspects of teleradiology in Germany]. / Medizinische und rechtliche Aspekte der Teleradiologie in Deutschland.

In teleradiology, imaging data are transferred over a distance. This service is provided for the purpose of consulting or teleradiological reading in the narrower sense. Once a justification has been proposed in the latter, the examination is performed under the responsibility of a radiologist who is not present on site. The need for teleradiology services often derives from sparsely populated areas, a shortage of doctors, or the need for cost-efficient provision of radiological examinations. The providers and recipients of teleradiology services enter into an agreement specifying conditions for data transfer. The German ionizing radiation (medical exposure) regulations demand that the teleradiologist holds radiation protection qualifications and is able to reach the examination site within 45 - 60 minutes. In Germany, teleradiology services are still limited to nights, weekends, and vacations, although the German regulations allow an expansion under certain circumstances. Efforts to fundamentally change radiology in favor of teleradiology are putting the status of a radiological medical act as well as current teaching models at risk, thereby indirectly sustaining physician shortage. Transnational teleradiology services offer the possibility of cost reduction, taking advantage of out-of-hour reading and wage fluctuation. At the same time, such services are associated with deficits in quality and availability of personnel as well as the quality of medical services. In the long-term teleradiology concepts will fundamentally change radiology. Smaller radiology units will concentrate on daily business and fast reporting. Larger units also providing academic teaching can use teleradiology networks to offer specialized readings.

Structural and ultra-structural features of the first mandibular molars of young rats submitted to pre and postnatal protein deficiencies.

The effects of protein malnutrition, both in utero and prior to weaning, on formation of the first mandibular molars were evaluated by phase-contrast and electron microscopy in rats. The nourished group (GI) received a diet that included 20% casein, while the malnourished group (GII) received 5% casein. The first mandibular molars from GII exhibited low density of cells and odontoblasts, which lacked regular organization compared with molars from GI. In addition, a difference in collagen type was observed between the groups, with a prevalence of Type III collagen fibers detected in the dentin, periodontal ligament, and alveolar bone of GII, and a prevalence of Type I collagen fibers in GI. Finally, examination of surface area in molar sagittal sections indicated 30% less dentin in GII, compared with GI. Our results suggest that structural and ultra-structural features of the dentin-pulp complex and periodontal components of rat molars are affected by protein deficiency.

Spatial trends and factors affecting variation of organochlorine contaminants levels in Canadian Arctic beluga (Delphinapterus leucas).

Organochlorine pesticides and PCBs were analysed in blubber from beluga (Delphinapterus leucas), or white whales, collected at 15 sites in the Canadian Arctic between 1993 and 2001. The objective of the study was to define and interpret the spatial trends of major organic contaminants in northern beluga in terms of sources and transport pathways, and the biological factors influencing accumulation. When compared on a lipid weight basis, the concentrations of beta-HCH, cis-CHL and SigmaCHL, cis-nonachlor, heptachlor epoxide and p,p'-DDT were significantly higher in males than females at all five sites in the eastern Arctic where the two sexes were harvested. The differences were attributed to losses from the females during fetal development and lactation as reported in previous studies. Major compounds increased with age in males at most sites, however the lack of a significant increase with age at some sites was in part due to high organochlorine concentrations in young year classes (2-5 years), particularly at eastern sites such as Iqaluit and Pangnirtung. Lower concentrations of SigmaHCH and SigmaDDT compounds in young males in 2001 relative to 1995 at Hendrickson Island could be due to declining levels in the environment, changes in the diet, or differences in organochlorine loads transferred from the female after birth. Age-corrected least square mean concentrations in males showed significantly higher levels of many compounds, such as p,p'-DDE and SigmaCHB, at south Baffin Island sites than those in the west. Two notable exceptions were HCBz and beta-HCH which were higher in the west. Methoxyclor was detected in males at Sanikiluaq (58 ng g-1) and in both sexes at Kimmirut, but at no other sites. Principal component analysis grouped the 16 sites into five major groupings based on the similarity of normalised organochlorine pesticide and PCB levels. Sites from the western Arctic were grouped by higher proportions of HCBz, beta-HCH and gamma-HCH and higher chlorinated PCBs. Endosulfan and alpha-HCH comprised a larger proportion of total organochlorine residues in the northern Hudson Bay sites, while methoxychlor, chlordane compounds and octachlorobiphenyls were enriched at Sanikiluaq in eastern Hudson Bay. The analysis showed that the relative amounts of several key compounds are similar in the beluga stocks over large spatial areas (i.e. eastern versus western sites), however, some stocks have distinct fingerprints which can be used to differentiate them from adjacent stocks. Ratios of major HCH isomers largely corresponded with air and surface water measurements conducted during the 1990s, but low alpha-/beta- and alpha-/gamma-HCH ratios in all three western Arctic collections indicate rapid losses of the alpha-isomer from the food web, proportionately higher beta- and gamma-isomers in the Beaufort Sea, or a combination of the two processes. Chlordane residue patterns generally correspond to those from previous studies, however, interpretation of spatial trends are difficult due to the aging of the probable sources in the south, possible atmospheric input from new sources and complex transport pathways.

Modern and historical fluxes of halogenated organic contaminants to a lake in the Canadian arctic, as determined from annually laminated sediment cores.

Two annually laminated cores collected from Lake DV09 on Devon Island in May 1999 were dated using 210Pb and 137Cs, and analyzed for a variety of halogenated organic contaminants (HOCs), including polychlorinated biphenyls (PCBs), organochlorine pesticides, short-chain polychlorinated n-alkanes (sPCAs), polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), and polybrominated diphenyl ethers (PBDEs). Dry weight HOC concentrations in Lake DV09 sediments were generally similar to other remote Arctic lakes. Maximum HOC fluxes often agreed well with production maxima, although many compound groups exhibited maxima at or near the sediment surface, much later than peak production. The lower than expected HOC concentrations in older sediment slices may be due to anaerobic degradation and possibly to dilution resulting from a temporary increase in sedimentation rate observed between the mid-1960s and 1970s. Indeed, temporal trends were more readily apparent for those compound classes when anaerobic metabolites were also analyzed, such as for DDT and toxaphene. However, it is postulated here for the first time that the maximum or increasing HOC surface fluxes observed for many of the major compound classes in DV09 sediments may be influenced by climate variation and the resulting increase in algal primary productivity which could drive an increasing rate of HOC scavenging from the water column. Both the fraction (F(TC)) and enantiomer fraction (EF) of trans-chlordane (TC) decreased significantly between 1957 and 1997, suggesting that recent inputs to the lake are from weathered chlordane sources. PCDD/Fs showed a change in sources from pentachlorophenol (PeCP) in the 1950s and 1960s to combustion sources into the 1990s. Improvements in combustion technology may be responsible for the reducing the proportion of TCDF relative to OCDD in the most recent slice.

Insulin resistance (metabolic) syndrome in children.

The insulin resistance (metabolic) syndrome (IRS), also known as syndrome X, is characterized by a clustering of factors associated with cardiovascular risk (obesity, impaired glucose metabolism, hypertension, and dyslipidemia). As reported from the third National Health and Nutrition Examination survey, the IRS is present in approximately 24% of adults in the United States and is strongly associated with coronary heart disease, stroke, type 2 diabetes, and all-cause mortality. Of equal importance, it is now clear that the origins of the IRS extend back into childhood (the IRS is found in approximately 4-10% of children and adolescents) and that the high prevalence of adult IRS is strongly linked to the development of cardiovascular risk during childhood and tracking of the components of the IRS into adulthood. The goal of this review is to present a summary of the currently available information on the IRS in the pre-adult age group with reference to adult studies only when necessary for clarification. The review will specifically summarize insulin resistance in childhood; the important influence of obesity and, in particular, visceral fat, on insulin resistance and the IRS; differences between ethnic groups; relations to adipocytokines, inflammatory factors and oxidative stress; relations of hypertension and lipids to insulin resistance; familial factors; endocrine complications; and potential therapeutic effects from diet and physical activity. Despite the lesser amount of basic and clinical information on childhood IRS in comparison to information available from adult studies, there can now be little doubt that the adverse associations among risk factors comprising the IRS begin in childhood. The challenge is to identify etiologic relations and develop intervention strategies designed to reduce the increasing prevalence of type 2 diabetes and cardiovascular disease.

Temporal trends of organochlorine pesticides in the Canadian Arctic atmosphere.

Temperature normalization (TN), multiple linear regression (MLR), and digital filtration (DF) were used to analyze the temporal trends of an atmospheric dataset on organochlorine pesticides (OCs) collected at the Canadian high arctic site of Alert, Nunavut. Details of these techniques have been presented before (Environ. Sci. Technol. 2001, 35, 1303-1311). Both the TN and DF methods revealed that the majority of OC pesticides declined over the 5 years of study, except endosulfan I and several of the pesticide metabolites, including dieldrin and p,p'-DDE. In comparison to studies conducted in the Great Lakes, atmospheric levels in the Arctic were less dependent on temperature, although seasonal variations were apparent. Generally, levels in the winter were lower than during the rest of the year. A notable exception was p,p'-DDE. Many compounds also showed a second minimum in concentrations during June/July and possible explanations are presented to account for this. The estimated first order half-lives for the decline in OC concentrations were generally found to be comparable or slightly longer than those obtained at temperate locations, with the exception of alpha-HCH, which displayed a much longer half-life in the Arctic (approximately 17 yrs). Sporadic increases in heptachlor as well as increases in the ratio of trans- to cis-chlordane suggest episodic input of chlordanes between 1995 and 1997, especially during the winter.

A novel thermoregulatory system maintains perioperative normothermia in children undergoing elective surgery.

BACKGROUND: Body heat loss during anaesthesia may result in increased morbidity, particularly in high-risk populations such as children. To avoid hypothermia, a novel thermoregulatory system (Allon) was devised. We tested the safety and efficacy of this system in maintaining normothermia in children undergoing routine surgical procedures. METHODS: The system consists of a computerized body, which receives continuous afferent data, i.e. core (rectal) temperature. These data are then compared with a preset temperature (37 degrees C) and a microprocessor heating/cooling unit warms/cools the temperature of circulating water in a garment that is specially designed to allow maximal coverage of body surface area, without impingement on the surgical field. Water temperature to the garment was limited to a maximum of 39.5 degrees C. Continuous perioperative monitoring of skin and rectal temperature, heart rate and blood pressure was performed. Postoperative shivering and adverse effects were also assessed. RESULTS: The Allon system was used in 38 patients aged 3 months to 14 years undergoing surgery under general anaesthesia lasting more than 30 min. Fifty to 80% body surface area was covered by the garment. Mean operative and postoperative core temperatures were 36.9 +/- 0.5 degrees C and 36.7 +/- 0.5 degrees C, respectively. Intraoperative skin temperatures were maintained at 34.4 +/- 2.7 degrees C. The average core- to-periphery intraoperative gradient was 2.9 +/- 4.9 degrees C. Postoperative shivering was absent in 36 cases and mild in two cases. No device-related adverse effects were observed. CONCLUSIONS: Perioperative thermoregulation using the Allon system is safe and effective in maintaining body temperature within a narrow range in children undergoing brief surgical procedures.

Ocular albinism type 1: more than meets the eye.

Ocular albinism type 1 (OA1) is an X-linked recessive disorder characterized by a severe reduction of visual acuity, and hypopigmentation of the retina that leads to nystagmus, strabismus, and photophobia/photodysphoria. Microscopic examination of both retinal pigment epithelium and skin melanocytes in OA1 reveals the presence of macrome-lanosomes, suggesting that the OA1 gene product plays a role in melanosome biogenesis. Studies of mutations identified from OA1 patients and an Oa1 knock-out mouse model further implicate OA1 protein function in the late stage of melanosome development. Because its effects are primarily limited to the eye, OA1 represents an ideal model system to study the relationship between pigmentation and visual development. Based upon sequence homology and biochemical studies, OA1 may represent a novel intracellular G-protein coupled receptor. Understanding the function of OA1 will contribute greatly to our understanding of melanosome biogenesis and the role of pigmentation in visual development.

Are PCBs in the Canadian Arctic atmosphere declining? Evidence from 5 years of monitoring.

A long-term database of weekly air concentrations was examined to establish temporal trends of PCBs in the Arctic atmosphere. Several methods were employed to reduce the intra-annual variability allowing the elucidation of longterm trends for a selection of congeners at Alert located in the Canadian Arctic. These methods included temperature normalization (TN), multiple linear regression (MLR), and digital filtration (DF). Estimation of the slope (m) resulting from the linear regression between the natural logarithm of the partial pressure in air versus reciprocal temperature (In P = m/T + b), required for TN and MLR, proved difficult due to the poor correlation with temperature experienced forthe majority of congeners. Values of m were considerably lower than those obtained from temperate studies, implying that regional air-surface exchange plays a minor role in supporting the observed air concentrations in the Arctic. The lighter congeners generally showed very low slopes, and some even showed positive correlation with 1/T. This might be a result of their relatively fast reaction rates with OH radicals following the onset of 24-h sunlight in spring. Use of DF (in combination with TN and MLR) revealed declining trends for several of the lower chlorinated congeners in the high Arctic atmosphere, with estimated first-order half-lives, t1/2, ranging from approximately 3 to 20 yr. Declining trends of the lower congeners probably reflect falling levels in source regions, as a result of long-range transport to this Arctic site. There were no apparent trends for the higher chlorinated congeners (penta-substituted and above), exceptfor PCB 180, in marked contrast to temperate studies, indicating a lag time for decline between the Arctic and source regions.

Intracellular distribution and late endosomal effects of the ocular albinism type 1 gene product: consequences of disease-causing mutations and implications for melanosome biogenesis.

To investigate the function of ocular albinism type 1 (OA1), the gene responsible for X-linked ocular albinism, we employed a construct containing murine Oa1 fused to green fluorescent protein (GFP) in a heterologous COS cell expression system. The cellular distribution of wild-type (WT) Oa1 protein and Oa1 proteins reflecting mutations causing X-linked ocular albinism were examined. Comparison with different organelle markers revealed that Oa1-GFP localized to the late endolysosomal compartments. Some Oa1 mutant proteins failed to exit the endoplasmic reticulum (ER) (Class I mutants), while other mutants partially (Class II mutants) or fully (Class III mutants) exited the ER and trafficked to endolysosomal compartments. We observed that expression of WT Oa1-GFP in COS cells caused an apparent enlargement of late endosomes and a redistribution of the mannose-6-phosphate receptor (M6PR). None of the mutants displayed the full range of effects on the redistribution of M6PR exhibited by WT Oa1. The effects of Oa1 on late endosome structure and content are thus likely to reflect an important biological property of Oa1. We propose that OA1 is involved in reorganizing the endolysosomal compartment as a necessary step in ocular melanosome biogenesis.

The work environment impact assessment: a methodologic framework for evaluating health-based interventions.

BACKGROUND: A new conceptual framework is needed to evaluate health-based interventions based on the premise that like the environment, workplaces are complex ecologies. The proposed Work Environment Impact Assessment (WEIA) is analogous to Environmental Impact Assessment (EIA), a concept and method developed 30 years ago in the environmental policy arena to evaluate potential consequences of human activity for the natural environment. WEIA entails identifying and evaluating both intended and unintended consequences, or outcomes, associated with a particular intervention. Because the workplace is a complex ecology, changes in one aspect may lead to changes in other aspects. WEIA calls for a systematic and comprehensive approach to the total work environment. METHODS: To illustrate the utility of WEIA we use this approach to evaluate an intervention to reduce the public's exposure to the pesticide Alar, which had been used on apples until it was withdrawn from the market in 1989. RESULTS: While this intervention did indeed reduce the public's exposure to Alar, it also led to other unintended consequences, namely new ergonomic hazards for apple pickers, increased stress levels in the orchards for both pickers and growers, as well as new worker, and perhaps public, exposure to potent neurotoxins. CONCLUSIONS: The goal of using WEIA is not to engage in a risk-risk debate that stalls worthwhile interventions. Rather, we propose that by conducting a Work Environment Impact Assessment, all possible positive and negative "ripple" effects stemming from an intervention can be considered, so that the intervention can be designed to achieve maximum benefit.

A bittersweet report from a New Orleans sugar refinery: working conditions and labor-management relations deteriorate together.

At the invitation of the president of United Food and Commercial Workers (UFCW) Local #1101, which represents workers at the Domino sugar refinery in Arabi, Louisiana, we met with several union members in the fall of 1998. Our purpose was to investigate workers perceptions of health and safety conditions in the plant and offer assistance in the amelioration of problems. We conducted in-person interviews, each lasting approximately 30 minutes, with the local union president and twelve members selected by the president.

The phytoestrogens coumoestrol and genistein induce structural chromosomal aberrations in cultured human peripheral blood lymphocytes.

The clastogenic potential of the phytoestrogens coumoestrol (COUM), genistein (GEN) and daidzein (DAI) has been studied in human peripheral blood lymphocytes in vitro. After exposure of the cultured lymphocytes to 50 to 75 microM COUM or 25 microM GEN for 6 h, a clear induction of structural chromosomal aberrations was observed by cytogenetic analysis. The major alterations were chromatid breaks, gaps and interchanges. In contrast, DAI did not induce chromosome aberrations even at 100 microM. These results, together with previously published reports on the induction of micronuclei and DNA strand breaks in cultured Chinese hamster V79 cells by COUM and GEN, but not DAI, suggest that some but not all phytoestrogens have the potential for genetic toxicity.

Use of a tobramycin-impregnated polymethylmethacrylate pin sleeve for the prevention of pin-tract infection in goats.

OBJECTIVE: To test the hypothesis that antibiotic-laden polymethylmethacrylate (PMMA) pin sleeves prevent infection around skeletal external fixation pins. DESIGN: An experimental study using an animal model was conducted. ANIMALS: In each of five goats, three four-millimeter half-pins were placed in the left and right iliac crests, for a total of thirty half-pins. The pins were infected with one milliliter of broth containing 7.6 x 10(5) colony-forming units per milliliter of Staphylococcus aureus (ATCC 25923). INTERVENTION: The pins in the right iliac crest were treated with the tobramycin-impregnated pin sleeves, and the pins in the left iliac crest (control) were left untreated. RESULTS: The results showed clinical evidence of infection (i.e., looseness and gross pus) and heavy bacterial growth (average 6.8 x 10(10) colony-forming units per milliliter) for the untreated pins, but no clinical evidence of infection and no bacterial growth at forty-eight hours for the treated pins. CONCLUSION: The present results indicate that the use of the antibiotic-impregnated PMMA pin sleeve can prevent the development of pin-tract infection and appears to prevent colonization of the external fixation pins.

Excision of the radial head in patients younger than 18 years.

We evaluated the results of an excision of the radial head in 25 patients (27 operated-on elbows) younger than 18 years with stiff painful radiocapitellar joints. The mean age was 14.2 years (range, 4.6-17.8 years) with average follow-up of 7.8 years. Analysis of the results with a postoperative elbow score revealed excellent or good results in 19 of the 27 elbows of patients. Skeletal maturity of the patient did not alter the results based on the rating scale. Revision surgery to remove appositional bone growth was needed in six of the 12 posttraumatic cases and one of 15 developmental elbows. Cubitus valgus, wrist pain, and ulnar neuropathy were not clinical problems at follow-up examination. Excision of the radial head was beneficial for 70% of patients younger than 18 years with stiff, painful radiocapitellar joints. Results were not improved in patients who had reached skeletal maturity.