Indoleamine 2,3-dioxygenase expression and functional activity in dendritic cells exposed to cholera toxin.

Indoleamine 2,3-dioxygenase (IDO), a tryptophan-metabolizing enzyme expressed by dendritic cells (DC), has the potential to inhibit T cell responses and to promote tolerance. In contrast, cholera toxin (CT), the enterotoxin produced by Vibrio cholerae, promotes T cell responses, partly through its ability to induce DC maturation and promote antigen presentation. We hypothesized that the adjuvant activity of CT is associated with a lack of induction of IDO in DC. To test this hypothesis, monocyte-derived DC were pulsed with CT, and the IDO mRNA expression, IDO functional activity and cytokine production were measured as well as the ability of DC to induce T cell responses in vitro. Cholera toxin exposure induced enhanced levels of IDO mRNA in DC but no functional IDO protein activity. Cholera toxin pulsing however primed DC for CD40L-induced IDO protein activity. CD40L stimulation of CT-pulsed DC induced a modest IL-12p40 production, but not IL-12p70 or IL-23 secretion. Furthermore, CT-pulsed DC induced strong allogeneic and autologous T cell responses in vitro, which were not affected by the IDO-specific inhibitor 1-methyl tryptophan. Our results show that CT per se does not induce the expression of functional IDO protein, although it primes DC for CD40L-mediated IDO production and IL-12p40 secretion. Furthermore, CT-treated DC were equally powerful in their T cell stimulatory capacity as cytokine-matured DC.

The incidence of acute hospital-treated eye injuries.

Little information is available on the incidence and severity of eye injuries despite the disfigurement and vision loss they cause. From a population-based study in Dane County, Wisconsin, the incidence of acute hospital-treated eye injuries was 423/100,000 residents in 1979. The most common causes of eye injuries were assaults, work-related events, sports and recreational activities, motor vehicle crashes, and falls. Consumer products were involved in almost 70% (9/13) of severe eye injuries classified as severe. Injuries from fireworks were not found at all in this population. Implementing known strategies for eye injury prevention would substantially reduce their incidence. These include requiring certified eye protectors at workplaces and in sports activities whenever possible rather than making their use voluntary. For the preponderance of eye injuries, however, modifying potentially hazardous consumer products, including the interior of passenger cars, will be necessary.

Injury control. A crucial aspect of emergency medicine.

We have briefly described the theoretic and strategic concepts of injury control and suggested ways for emergency medicine to be more broadly involved. It is not enough for emergency physicians to be active solely in the acute management of injured patients. Emergency physicians need to "look upstream" and balance their focus on the acute management of injuries with a focus on the prevention of injuries.

An anatomic index for the severity of ocular injuries.

Ocular injuries are a frequent cause of monocular blindness and cause disfigurement and discomfort. We developed a measure of severity for eye injuries using a multi-attribute utility (MAU) model. The severity index scoring was applied to eye injuries that presented at hospitals in Wisconsin, U.S.A. The resulting distribution of severities was compatible with that seen by general eye care physicians. A severity scale provides a means of comparing the severity of injuries from a wide variety of traumatic sources (e.g. automobile crashes, combat injuries, occupational accidents, etc.) and is useful in evaluating preventive and public health measurements.

Proinflammatory cytokine synthesis by mucosal fibroblasts from mouse colitis is enhanced by interferon-gamma-mediated up-regulation of CD40 signalling.

Gut mesenchymal fibroblasts form complex phenotypical and functional populations. They participate actively in homeostatic maintenance of the extracellular matrix, epithelial barrier function, repair mechanisms and leucocyte migration. In inflammation, they become activated, change matrix expression and synthesize proinflammatory mediators. Subpopulations of mucosal fibroblasts express CD40 and the aim of this study was to define its role in their proinflammatory function. Stable primary fibroblast lines derived from normal mouse colon and inflamed colon from CD4(+) CD45RB(high)-transplanted SCID mice were used as models to explore the role of mucosal fibroblast CD40 in the inflammatory process. Phenotype correlated with in situ fibroblast phenotype in the tissues of origin. Lines from both sources co-expressed CD40 and Thy1.2 independently of alpha-smooth muscle actin. A subpopulation of CD40(+) fibroblasts from normal colon expressed CD40 at high levels and expression was enhanced by interferon (IFN)-gamma treatment, whereas all CD40(+) fibroblasts from colitis expressed at low levels and expression was unaffected by IFN-gamma treatment. Despite lower-level expression of CD40 by cells from colitis, they secreted constitutively interleukin (IL)-6 and C-C chemokine (CCL)2. Ligation of CD40 enhanced secretion of these mediators and induced secretion of CCL3. CD40 in cells from colitis was more responsive to ligation than CD40 on cells from normal tissue and this sensitivity was amplified selectively by the action of IFN-gamma. We conclude that the inflammatory milieu in colitis induces long-lasting changes in phenotype and proinflammatory function in colonic fibroblasts. In particular, proinflammatory signalling from fibroblast CD40 is amplified synergistically by the Th1 effector T cell cytokine, IFN-gamma.

The incidence of hospital-treated facial injuries from vehicles.

The annual incidence rate of facial injuries from vehicle crashes, 278 per 100,000 residents, was determined from a population-based study involving all Dane County, Wisconsin, hospitals with emergency departments. Applying this figure to the U.S. population yields an estimated 625,000 hospital-treated facial injuries from vehicles occurring in the United States each year. Vehicle crashes were the source of a substantial proportion of facial injuries from all causes, and were found to be the single leading cause of the most severe facial lacerations and facial fractures. The majority of injuries were sustained by drivers and other vehicle occupants, and others by bicyclists, motorcyclists, and pedestrians struck by vehicle. Vehicle occupants' faces were most commonly injured by steering wheels and windshields. Technologies which are thought to protect occupants include airbags and nonlacerating windshields, but neither is available in vehicles currently manufactured for sale in the United States.

The incidence of facial injuries from dog bites.

The incidence of hospital-treated facial injuries caused by dog bites was determined from a population-based study involving Dane County, Wisconsin, hospitals during 1978 and 1979. Annual rates were shown to be 152 per 100,000 for ages 0 to 4 years, 128 per 100,000 for ages 5 to 9 years, and 62 per 100,000 for ages 10 to 14 years. Severe facial injuries from dog bites were found almost exclusively in children younger than 10 years. If these rates apply to children in the US population, then an estimated 44,000 facial injuries, 16,000 of them severe, caused by dog bites are seen in hospitals each year. The cumulative incidence of facial injuries from dog bites for children to age 14 years is 1.6%. Most of the published advice for preventing dog bite injuries to the face suggests parental diligence in keeping children away from dogs, but options such as choosing dogs less likely to bite children may be more effective.

Farm tractor fatalities: the failure of voluntary safety standards.

There are no governmental standards for operator protection which require compliance by farm tractor manufacturers. To see how the Wisconsin farming population fares under voluntary safety standards, death certificate data were used to determine rates of tractor-associated fatal injuries. The injury deathrate associated with tractors on farms increased from 10.9 per 100,000 male farm residents during 1961-1965 to 13.6/100,000 during 1971-1975 (p less than .05). Deaths associated with overturning tractors were most common; with death rates of 6/100,000 male farm residents for 1961-1975. The rise in tractor-associated death rates shows that voluntary safety standards are not protecting the farm population. Rollover protective structures (ROPS) are designed to protect operators when tractors overturn but under voluntary safety standards these ROPS are sold only as optional accessory devices. Current Occupational Safety and Health Administration regulations which require ROPS for employees operating tractors do not protect self-employed farmers and their families. It is recommended that the government require all tractors sold to be equipped with ROPS as is currently the case in England and Sweden.

Motor vehicle crashes and seat belts: a study of emergency physician procedures, charges, and documentation.

STUDY OBJECTIVE: To study emergency physician documentation of seat belt use, practice patterns, and charges for patients with different restraints involved in motor vehicle crashes. DESIGN: Retrospective examination of 2,239 emergency department records during a 5-month period. PARTICIPANTS: Patients from four community EDs and one Level I trauma center ED. RESULTS: Documentation of seat belt use for motor vehicle crash occupants was reported in 70% of the ED records reviewed. Only 64.5% of the records from the four community hospital EDs recorded seat belt use, compared with 81.7% of the records from the trauma center ED (P < .001). The unbelted group had a greater mean number of physician procedures performed (1.4 versus 1.2; P < .001) and more radiographs of the face and skull ordered (11.9% versus 8%, P < .01). Seat belt users had a higher average number of cervical-spine radiographs ordered than did nonusers (71.5 versus 65.7; P < .05). Physician charges for unbelted patients were higher compared with those for belted patients, averaging $22.00 more per patient (P < .001). CONCLUSION: Emergency physician practice patterns reflect the distribution of injuries associated with seat belt use and nonuse. Reduced physician charges for belted patients contributed to health care cost savings. Emergency physicians should be encouraged to consistently obtain and record whether an individual was wearing a seat belt during a motor vehicle crash.

Characteristics of firearms involved in fatalities.

OBJECTIVES: To document the types of firearms associated with firearm fatalities, and to determine the availability of information on firearm characteristics in existing data sources. DESIGN: Review of police, medical examiner, and crime laboratory records for all firearm homicides and review of medical examiner records for all suicides and unintentional and undetermined firearm fatalities. SETTING: City of Milwaukee, Wis, from 1990 through 1994. POPULATION: A total of 175 firearm suicides and 524 firearm homicides. MAIN OUTCOME MEASURES: Source of data; circumstances and means of death; host demographic characteristics; firearm make, model, caliber, barrel length, and serial number. RESULTS: Handguns accounted for 468 (89%) of 524 firearm homicides and 124 (71%) of 175 firearm suicides. Handguns of .25 caliber accounted for 14% (n = 63) of 438 firearm homicides and 12% (n = 15) of all firearm suicides in which caliber was known. The Raven MP-25 was the single most commonly identified firearm and accounted for 10% (n = 15) of 153 handgun homicide cases and 7% (n = 7) of the 76 suicide cases in which the manufacturer of the firearm was identified. From all data sources combined, information on firearm type was available in 681 (97%) of 699 cases, caliber/gauge in 636 cases (91%), manufacturer/model in 309 cases (44%), and serial number in 276 cases (40%). CONCLUSIONS: Inexpensive, short-barreled .25-caliber handguns were the most common weapon type associated with firearm homicides and suicides in Milwaukee during 1990 through 1994. Product-specific information is a crucial part of planning appropriate injury countermeasures for firearms. In combination, police, crime laboratory, and medical examiner data can supply this information with modest changes in data collection procedures.

Motorboat propeller injuries in Wisconsin: enumeration and prevention.

STUDY OBJECTIVE: To ascertain the nature and extent of motorboat propeller injuries in Wisconsin. DESIGN: Retrospective study of deaths and injuries from outboard motor propellers reported to the Wisconsin Division of Health, Vital Statistics, and reported by a statewide retrospective survey of emergency departments. RESULTS: For the study period 1987 through 1989, three fatalities were found in Vital Statistics and Emergency Department records and 14 nonfatal injuries reported by respondents to the Wisconsin emergency department survey. Thirty-six percent (5 of 14) of the nonfatal injuries occurred in water skiers. Injuries involved the lower extremities in 10 of 14 nonfatal cases (71%), frequently in association with other anatomic areas. At least three cases involved very severe injuries, with mean acute care medical charges of more than $100,000 per case. CONCLUSIONS: Where boating is common, fatal and severe injuries from propellers occur with regularity. These injuries are often severe, requiring complicated and expensive treatment. The authors urge improved documentation of the incidence of propeller injuries, and an active exploration of prevention strategies including fitting motorboat propellers with guards.