Trauma 24-hour observation critical path

BACKGROUND

The 24-hour observation critical pathway for trauma is a clinical tool developed to expedite health care delivery to minimally injured patients. The use of patient care, BS, guidelines and physician-approved standing orders was implemented in a Level I trauma center.

METHODS

A retrospective chart review was performed of 122 patients admitted via the emergency department between December 1, 1993, and May 31, 1994. All patients were evaluated in the emergency department by emergency medicine and trauma physicians and deemed appropriate for 24-hour observation. The information collected included patient demographics, hospital charges, injuries, length of stay, diagnostic tests, consultations, and variances from the critical pathway.

RESULTS

During the 6-month study period, there were 600 trauma admissions. Of those admissions, 122 patients (20%) were evaluated in the emergency department and deemed appropriate for enrollment in the 24-hour observation pathway. The charts of these patients were reviewed. Fourteen admissions were determined inappropriate for the critical pathway because of the severity of injuries or discharge against medical advice. One hundred eight charts were evaluated further. Eighty-nine patients (80%) completed the critical pathway with a length of stay of 24 hours.

CONCLUSION

The 24-hour observation critical pathway was designed and used appropriately as exemplified by an overall 80% completion rate. The critical pathway offers a mechanism to streamline care of the minimally injured trauma patient. It also serves as a quality-improvement tool for increasing efficiency, decreasing utilization of resources, and decreasing length of stay.

Splenosis of the mesoappendix: case report and review of the literature

The development of splenosis is a known consequence of splenic rupture. A case is presented of acute appendicitis in a patient with a past history of abdominal trauma who required laparotomy for unknown reasons. During appendicectomy a mass was found in the mesoappendix which proved to be evidence of splenosis.

Evaluation of mechanism of increased intracranial pressure with insufflation

BACKGROUND

Previous studies have documented an increase in intracranial pressure with abdominal insufflation, but the mechanism has not been explained.

METHODS

Nine 30-35-kg domestic pigs underwent carbon dioxide insufflation at 1.5 l/min. Intracranial pressure (ICP), lumbar spinal pressure (LP), central venous pressure (CVP), inferior vena cava pressure (IVCP), heart rate, systemic arterial blood pressure, pulmonary arterial pressure, cardiac output, heart rate, respiratory rate, temperature, and end-tidal CO2 were continuously measured. Mechanical ventilation was used to maintain a constant pCO2. Measurements were recorded at 0, 5, 10, and 15 mmHg of abdominal pressure with animals in supine, Trendelenburg (T), and reverse Trendelenburg (RT) positions. Prior to recording measurements, the animals were allowed to stabilize for 40 min after each increase in abdominal pressure and for 20 min after each position change.

RESULTS

The animals showed a significant increase in ICP (mmHg) with each 5-mmHg increase in abdominal pressure (0 mmHg: 14 +/- 1.7; 5 mmHg: 19.8 +/- 2.3, p < 0.001; 10 mmHg: 24.8 +/- 2.5, p < 0.001; 15 mmHg: 29.8 +/- 4.7, p < 0.01). The ICP at 15 mmHg abdominal pressure increased further in the T position (39 +/- 4, p < 0.01). Insufflating in the RT position did not significantly reduce the increase in ICP. The IVCP (mmHg) increased with increased abdominal pressure (0 mmHg: 11.5 +/- 6.2, 15 mmHg: 22.1 +/- 3.5, p < 0.01). This increase correlated with the increase in ICP and LP (r of mean pressures >/=0.95). There was no significant change in CVP.

CONCLUSIONS

This study suggests that care may be needed with laparoscopy in patients at risk for increased ICP due to head injury or a space occupying lesion. The mechanism of increased ICP associated with insufflation is most likely impaired venous drainage of the lumbar venous plexus at increased intraabdominal pressure. Further studies of cerebral spinal fluid movement during insufflation are currently underway to confirm this hypothesis.

Painless osteoid osteoma of the middle phalanx

A 12-year-old girl with a painless swollen finger was a clinical puzzle as her presentation and X-rays were not typical of osteoid osteoma. Computed tomography and histology confirmed the diagnosis. This case is reported for its atypical presentation, difficulty in diagnosis and rare occurrence in the middle phalanx.

Detection of wild-type Aujeszky's disease virus by polymerase chain reaction in sheep vaccinated with a modified live vaccine strain

An outbreak of Aujeszky's disease occurred in a flock of sheep which had been housed together with pigs. After the death of five sheep with clinical signs of Aujeszky's disease, the remaining sheep were vaccinated with the Bartha vaccine strain, and the pigs were vaccinated with the 783 vaccine strain of Aujeszky's disease virus. Despite vaccination, however, more sheep died. Brain tissues from four sheep were collected for virus isolation and for immunohistological examinations. Only vaccine virus (gE-negative) was detected in the tissue. After DNA restriction enzyme analysis of the isolated virus, DNA of one or both of the vaccine strains was detected in all sheep. In one sheep field virus DNA was also detected. However, when the polymerase chain reaction was performed on samples prepared from paraffin-embedded tissues, DNA of field virus (gE-positive) was detected in all four sheep. It was probable that the sheep had not yet mounted a sufficient immune response to the vaccine virus, or were already infected with field virus at the time of vaccination. We concluded that the sheep died from field virus infection and not from vaccine virus infection and that only the polymerase chain reaction made it possible to specifically detect even very small amounts of field virus DNA among vaccine virus DNA in all investigated sheep.

Pseudorabies virus infections in pigs. Role of viral proteins in virulence, pathogenesis and transmission

This paper reviews new findings on the biological functions of pseudorabies virus (PRV) proteins. It focuses on the role of PRV proteins in the pathogenicity, immunogenicity and transmission of PRV vaccine strains in pigs. Furthermore, it evaluates potential risks that are connected with the use of PRV vector strains. Special emphasis is placed upon the spread of genetically engineered vaccine strains within pigs or between pigs.

The impact of complications after vascular surgery in Veterans Affairs Medical Centers

The impact of perioperative complications on clinical outcomes and resource utilization was assessed for 8702 veterans who, during fiscal years 1991-1994, underwent vascular surgery procedures in DRGs 110 and 111, which include aortic and peripheral aneurysm repairs as well as renal artery and some peripheral vascular reconstructions. In-hospital mortality rate was 6.2% (537/8702). Mortality was 9.8% with any ICD-9-CM-coded complication vs 4.9% without (P < 0.001). Mortality was 28.9% in those with both cardiac and pulmonary complications, 11.0% with either cardiac or pulmonary complications, and 3.7% with neither cardiac nor pulmonary complications. Length of stay (LOS) was 25.8 +/- 21.9 days with any ICD-9-CM-coded complication vs 18.9 +/- 14.1 days without (P < 0.001). Further, RIS (Resource Intensity Scale), a measure of intensity of resource utilization, was greater in those with (3.01 +/- 0.81) vs without (2.76 +/- 0.70; P < 0.001) a complication. Pulmonary complications impacted LOS and RIS more adversely than cardiac. A logistic regression model of mortality indicated that increasing age [odds ratio (OR) 1.065], arrhythmia (OR 1.31), pneumonia (OR 2.52), surgical complications of the heart (OR 2.8), respiratory insufficiency (OR 4.75), stroke (OR 5.48), MI (OR 5.78), and acute renal failure (ARF, OR 9.58) were associated with increasing likelihood for death, whereas treatment in the largest, academically affiliated VAMCs (RPM 5) was associated with reduced mortality (OR 0.795). Increasing age, treatment in the largest affiliated (RPM 5) hospitals, arrhythmia, MI, CHF, any ICD-9-CM-coded complication, acute renal failure, respiratory insufficiency, pneumonia, and stroke progressively increased LOS by linear regression analysis, whereas surgical complications of the heart and postoperative death reduced LOS. Complications after vascular surgery have an adverse impact on perioperative mortality, length of stay, and utilization of resources.

A model for an integrated emergency medicine/trauma service

OBJECTIVE

To describe a model for an integrated multidisciplinary trauma service and to compare survival outcomes for patients resuscitated by either emergency medicine (EM) or surgical housestaff assigned to the trauma service.

METHODS

A prospective observational study was performed using injured patients evaluated in the trauma room at Hartford Hospital from July 1 through December 31, 1995. Inclusion criteria included an ICD-9-CM code of 800 through 959.9 and any of the following: transfer from another hospital, admission to the intensive care unit, hospitalization for > or = 23 hours, survival probability of < or = 90%, or Abbreviated Injury Score of > or = 3. Patients were excluded for burns necessitating transfer to a burn unit for definitive care, and for missing data elements that prevented a patient from being analyzed by the TRISS method. Data elements included mechanism of injury, Injury Severity Score, Revised Trauma Score, probability of survival, age, gender, and whether an EM resident was team leader. Patients in the EM cohort (group 1) were compared with patients for whom a surgical resident was team leader (group 2) for all data elements and for hospital survival. TRISS analysis was performed to evaluate outcomes in comparison with national norms.

RESULTS

After exclusions, 609 patients were left for analysis. There were 141 (30%) resuscitated with an EM resident as team leader. No significant difference was found for matched variables between the groups. Both groups had good comparability with the Major Trauma Outcome Study (MTOS) database baseline, with M scores of 0.949 and 0.942, respectively. Outcomes for both groups also compared favorably with the MTOS norm for survival, with Z scores of 2.38 and 2.35 for groups 1 and 2.

CONCLUSIONS

These results suggest that in this model of integrated EM/trauma service, equivalent survival outcomes occur whether EM or surgery housestaff act as team leaders.

Clinical analysis of the utility of repeat computed tomographic scan before discharge in blunt hepatic injury

OBJECTIVES

Nonoperative management of hemodynamically stable blunt hepatic injury has emerged as an acceptable and safe treatment. Surveillance of this population's injuries is costly. As a prelude to establishing practice guidelines, the utility of repeat computed tomographic (CT) scans was investigated.

METHODS

A retrospective study was conducted on 243 hepatic injuries. The CT scans of 95 patients managed nonoperatively who did not have ongoing transfusion requirements were reviewed and graded according to the American Association for the Surgery of Trauma (AAST) hepatic injury scale. Patients were grouped according to injury grade, assigned to two subgroups (patients with one CT scan versus more than one CT scan) and compared with respect to several physiologic and clinical variables.

RESULTS

Statistical analysis revealed no significant difference between subgroups with the same grade of injury. No significant difference was demonstrated between subgroups' length of stay.

CONCLUSIONS

No patients failed nonoperative treatment or succumbed to their injuries. Findings on repeat CT scan have not altered the decision to discharge the clinically stable patient having suffered a grade III or lower liver injury.

Lack of serum antibodies against glycoprotein E in pseudorabies virus-immune pigs infected with wild-type virus

OBJECTIVE

To examine whether pigs with solid immunity against pseudorabies virus (PRV) could harbor latent infection with wild-type PRV without developing antibodies against glycoprotein E (gE), which is used as a marker protein to differentiate pigs that have been vaccinated from pigs infected with wild-type PRV.

ANIMALS

Specific-pathogen-free pigs that were seronegative for antibodies to PRV.

PROCEDURE

Oropharyngeal swab specimens were collected, and virus content was measured, Serum samples were obtained 1 week before and 2 and 4 weeks after challenge exposure. Four weeks after challenge exposure, pigs were slaughtered; various tissues were collected for virus isolation, and DNA was analyzed by polymerase chain reaction.

RESULTS

Of the intranasally inoculated pigs, only 1 pig shed virus (for 1 day) but none developed antibodies directed against gE. Of the inoculated IM pigs, 3 pigs shed virus (for several days) and 5 developed antibodies directed against gE. One pig did not shed virus and did not develop detectable gE antibodies. However, variable amounts of wild-type virus DNA were detected in various tissues.

CONCLUSIONS

Immunized pigs can be infected with wild-type PRV without being detected by the gE-specific ELISA, which is routinely used to discriminate between infected and vaccinated pigs. The implication for eradication programs is that these pigs might be a source of new outbreaks.

An indirect double-antibody sandwich enzyme-linked immunosorbent assay (ELISA) using baculovirus-expressed antigen for the detection of antibodies to glycoprotein E of pseudorabies virus and comparison of the method with blocking ELISAs

Antibodies in porcine sera against glycoprotein E (gE) of pseudorabies virus (PRV) are usually measured in blocking enzyme-linked immunosorbent assays (ELISAs) with one or two murine monoclonal antibodies (MAbs) directed against gE. Our aim was to develop a confirmation assay which is based on another principle and which is able to detect antibodies directed against most potential binding sites on gE with high specificity. Therefore, we developed an indirect double-antibody sandwich assay (IDAS) using recombinant gE expressed by baculovirus (BacgE960). A fragment of the gE gene consisting of nucleotide positions +60 to +1020 of gE, coding for the major antigenic sites of gE but not the transmembrane region, was cloned behind the signal sequence of PRV gG and the p10 promoter in a baculovirus vector. Immunoblot analysis showed that the expressed protein reacted with MAbs directed against five of the six antigenic sites on gE. Although the conformation of some antigenic sites, notably antigenic sites E and C, was not identical to their natural conformation, the expressed protein bound gE-specific antibodies in porcine sera in Western blots (immunoblots) and ELISAs. For the IDAS, a coating MAb directed against the nonimmunodominant antigenic site A on gE was chosen. A major obstacle in binding ELISAs, such as the IDAS, appeared to be the high nonspecific binding activity observed in porcine sera. As a result, sera could be tested only in relatively high dilutions in the BacgE960 IDAS, in contrast to the testing of sera in blocking ELISAs. The sensitivity and specificity of the newly developed BacgE960 IDAS were evaluated and compared with those of five commercially available blocking ELISAs by using several sets of sera of known PRV disease history. The BacgE960 IDAS assay had a high diagnostic specificity and a moderate sensitivity. The five blocking ELISAs differed remarkably in sensitivity and specificity, thereby illustrating the need for standardization and confirmation. We conclude that the BacgE960 IDAS is a useful and specific additional (confirmatory) test for the detection of antibodies to gE.

Abdominal aortic aneurysm repair in Veterans Affairs medical centers

PURPOSE

This study was performed to define outcomes after abdominal aortic aneurysm (AAA) repair in Veterans Affairs (VA) medical centers during fiscal years 1991 through 1993.

METHODS

With VA patient treatment file data, patients were selected from diagnosis-related groups 110 and 111 and were then classified in a patient management category. In the categories of repair of nonruptured and ruptured AAA, mortality and postoperative complication rates were defined for patients who underwent AAA repair in VA medical centers during the 3-year study period.

RESULTS

Hospital mortality rates were 4.86% (166 of 3419) after repair of nonruptured AAA and 47.0% (126 of 268) after repair of ruptured AAA (p<0.001). Of 292 deaths after AAA repair, 136 (43.2%) followed repair of ruptured AAA, even though ruptured AAA comprised only 7.3% of total AAA surgical volume. AAA repairs were performed at 116 VA medical centers, with 31.8+/-23.1 (range, 1 to 140) procedures performed at each center. Although many lower-volume centers had excellent results, centers that performed >or=32 AAA repairs tended to have lower in-hospital mortality rates after repair of nonruptured AAA than those that performed <or=31 procedures (4.2%+/-3.5% compared with 6.7%+/-7.8%;p<0.05). Poisson regression analysis revealed an inverse relationship between the volume of AAA repairs and individual hospital mortality (p=0.001) and a direct relationship between illness severity and hospital mortality (p=0.008). The proportion of ruptured AAAs treated in a hospital was also directly related to individual hospital mortality rates (p<0.005). Postoperative complications were associated with an increased hospital mortality rate (11.7% with complication compared with 6.5% without; p<0.0001) and length of stay (23.6+/-17.1 days compared with 18.0+/-12.4 days; p<0.0001). In a logistic regression model, increased mortality rates after AAA repair were associated with hospital type (adjusted odds ratio [OR]=0.6), increasing age (OR=1.1), patient management category severity score (OR=2.2), hemorrhage (OR=2.3), myocardial infarction (OR=2.6), disseminated intravascular coagulation (OR=4.7), AAA rupture (OR=6.0), postoperative shock (OR=10.7), cardiopulmonary arrest (OR=15.4), central nervous system complications (OR=16.0) and urologic complications (OR=2.4).

CONCLUSIONS

Mortality rates after AAA repair in VA hospitals were comparable with those previously reported in other large series. Outcomes for veterans with AAA may improve by referring patients eligible for elective repair to VA medical centers with a greater operative volume or to lower-volume centers that have had excellent results.

Circulating natural killer cells but not cytotoxic T lymphocytes are reduced in patients with active relapsing multiple sclerosis and little clinical disability as compared to controls

Triple antibody flow cytometry was used to compare the populations of CD56+ effector cells in the peripheral circulation of 29 patients with relapsing multiple sclerosis (MS) and little disability who were exacerbation-free for over 2 months and 29 healthy control subjects. Populations were characterized by two panels of antibodies (CD8, CD16, CD56 and CD3, CD8, CD56), as well as by size or granularity. In the MS patients, mature natural killer (NK) cells (CD3-CD8-CD56+) of small size and low granularity were significantly reduced compared to normals (P(0.0003). The quantities of other effector cells (cytotoxic T lymphocytes, large granular lymphocytes and monocytes) were not different in MS patients compared to the control subjects. Also, we identified a previously unrecognized population of CD56+ monocytes (CD3-CD14+CD56+) in both the normal control subjects and the MS patients which would have been misclassified as NK cells using one or two antibody cytometry employed in previous studies.

Conservative management of ovarian hyperstimulation syndrome

OBJECTIVE

To evaluate the performance of a conservative treatment protocol for ovarian hyperstimulation syndrome (OHSS) that utilized low-dose dopamine, volume expanders and diuretics.

STUDY DESIGN

Prospective, open trial.

RESULTS

Thirteen patients met the criteria for diagnosis of severe OHSS during the study period. Two of these were in vitro fertilization (IVF) patients who did not undergo transfer and so were excluded from analysis. Of the remaining 11, 10 (91%) were pregnant. The average time for resolution of the OHSS and discharge from the hospital was 6 days (range, 2-11). Compared to levels at admission, there was no significant difference in those of sodium, potassium or creatinine after resolution of the syndrome. Hemoglobin and hematocrit, however, were significantly reduced (P < .03). There were no cases of adult respiratory distress syndrome or thrombosis. No pregnancies were interrupted.

CONCLUSION

Conservative treatment of OHSS is an acceptable form of management. Risky and invasive therapies, such as paracentesis, are not warranted.

National Medical Association Surgical Section position paper on violence prevention. A resolution of trauma surgeons caring for victims of violence

The epidemic of intentional injury continues to be a leading cause of premature death in America. The ravages of violence are particularly devastating within the minority community. With this position paper from the Surgical Section of the National Medical Association (the country's oldest and largest organization of minority physicians), a group of trauma surgeons and surgical intensivists resolve to focus on underused violence prevention opportunities and to extend their spheres of influence beyond the walls of their institutions and emphasize violence prevention activities.

Case report: hypoglycemia secondary to a meningioma

Hypoglycemia secondary to a meningioma that has not metastasized to the liver has not been reported previously. A 41-year-old woman with a spinal cord meningioma first diagnosed 5 years previously with 3 recurrences in the spinal cord resulting in 4 neurosurgical procedures was admitted with a serum glucose of 23 mg/dL. Six months before the current admission, the patient was noted to have an abdominal mass of 10 cm not present on previous computed tomography. Three months later, the mass was 15.2 cm, and on the current admission, had increased to 23 cm and encased both the aorta and inferior vena cava. A needle biopsy of this mass before referral to the authors' hospital with hypoglycemia revealed that it was a meningioma. Evaluation of the etiology of the hypoglycemia, which required continuous intravenous glucose therapy, revealed that circulating insulin, C-peptide (i.e., connecting peptide), insulin-like growth factor-I (i.e., somatomedin-C) and insulin-like growth factor-II were all normal or low. Serum cortisol also was not low. Based on her endocrine evaluation, the hypoglycemia was secondary to the large mass of tumor cells, requiring a large glucose uptake to sustain its growth. After radiation therapy of 3,770 CGy to the meningioma, the patient became euglycemic without glucose supplementation.

Clinical nurse practitioner in a surgical team

The role of a nurse taking on many of the duties of PRHO in a surgical team is described with the responsibilities, relationships and limitations. A nurse can carry out almost all of the elective activity of a PRHO and significantly relieve the pressure of work on others. She cannot completely substitute for PRHOs out of hours. As more consultants are appointed without additional medical members of the team, it is suggested that two consultant teams might be best served by one PRHO working with one Clinical Nurse Practitioner.

A brief history of the use of interferons as treatment of multiple sclerosis

Interferons (IFNs) are a family of glycoproteins that are naturally secreted by certain cells in response to viral infection. The naturally occurring IFNs confer protection on other cells, preventing them from becoming infected, a phenomenon referred to as "virus interference" by Isaacs and Lindenmann in the first description of these proteins. In addition to their antiviral properties, the IFNs also have complex immunomodulatory, antiproliferative, and hormonelike activities, which are not completely understood.

The lesion causing continuous facial myokymia in multiple sclerosis

OBJECTIVE

To attempt to identify the site of the lesion causing continuous facial myokymia (CFM) in multiple sclerosis (MS) through the use of magnetic resonance imaging (MRI).

DESIGN

A case series was employed.

SETTING

The Baird Multiple Sclerosis Center, Millard Fillmore Hospital, and the Neurology Department, Buffalo General Hospital, Buffalo, NY.

PARTICIPANTS AND MEASURES

Twelve patients with MS and CFM were examined by MRI of the brain while the CFM was present. The MRI examinations were also performed before the CFM had developed and after it had ceased in eight of the patients. Another 57 patients with MS who never had CFM but who had similar disabilities to those who did were also examined by MRI.

RESULTS

In 11 of the 12 patients with MS and CFM, the causative lesion was demonstrated to involve the postnuclear, postgenu portion of the facial nerve intraaxially in the dorsolateral pontine tegmentum ipsilateral to the CFM. In the majority of patients who were studied after the CFM had stopped clinically, the lesion was observed to resolve on MRI. Seventeen percent of the patients with MS but without CFM were found to have the typical pontine tegmental lesion.

CONCLUSIONS

Continuous facial myokymia in MS is caused by a pontine tegmental lesion involving the postnuclear, postgenu portion of the facial nerve. The lesion is identified by MRI in approximately 90% of patients with MS who have CFM clinically. The typical MRI lesion may also be found in a minority of patients with MS who do not have CFM clinically.

Glycoprotein gE-negative pseudorabies virus has a reduced capability to infect second- and third-order neurons of the olfactory and trigeminal routes in the porcine central nervous system

We investigated the spread of glycoprotein gE (gE)-negative pseudorabies virus (PRV) and its rescued 'wild-type' strain into and within the central nervous system (CNS) of 3- and 10-week-old pigs. This is the first study that demonstrates PRV invasion of the porcine CNS via the synaptically linked neurons of the olfactory and trigeminal routes and that demonstrates the role of gE in this invasion. After intranasal inoculation with high doses of virus, gE-negative PRV replicated less efficiently in peripheral tissues. The titres of the gE-negative virus in the oropharyngeal mucosa, olfactory epithelium, draining lymph nodes and trigeminal ganglion were approximately 100-fold lower in 3-week-old pigs and 10-fold lower in 10-week-old pigs than titres of the 'wild-type' virus. In contrast to the 'wild-type' virus, titres of the gE-negative virus were very low or undetectable in the olfactory bulb, brain stem and other tissues of the CNS. Viral antigen of rescued 'wild-type' PRV and of gE-negative PRV was detected immunohistochemically in the olfactory epithelium and in neurons of the trigeminal ganglion, and also in the olfactory and trigeminal axons leading towards the CNS. But, in contrast to 'wild-type' virus, no viral antigen of the gE-negative virus was detected in second- or third-order neurons in the olfactory bulb or in the brain stem. We conclude that gE-negative PRV can infect first-order neurons of the olfactory and trigeminal routes and is able to spread via their axons towards the CNS. Yet, gE-negative PRV has a greatly reduced capacity to infect second- or third-order neurons. Finally, we report lateral spread of 'wild-type' PRV in the trigeminal ganglion, i.e. nonsynaptic transport from neuron to neuron. Possible mechanisms that could explain the reduced levels of the gE-negative virus in the CNS are discussed.

Epitope-specific antibody response against glycoprotein E of pseudorabies virus

In this study we investigated the epitope-specific antibody response against glycoprotein E (gE) of pseudorabies virus. Epitope-specific antibody responses were investigated by enzyme-linked immunoperoxidase monolayer assays. In a vaccinated crossbred pig population, most pigs responded to antigenic domain E and to a lesser degree to antigenic domains C and D. Only few pigs responded to antigenic domains F, A, and B. Using vaccinated pigs, we investigated the influence of two different pseudorabies virus strains and the genetic background of the host on the epitope-specific antibody response. More pigs infected with the virulent NIA-3 strain had a detectable antibody response against antigenic domains C, F and A than did pigs infected with the mildly virulent Sterksel strain (P < or = 0.05; Fisher's exact test). No differences in the epitope-specific antibody responses of two genetically different pig breeding lines were observed (P > or = 0.1; Fisher's exact test). In both breeding lines the incidence of the epitope-specific antibody response was comparable to that in the crossbred pig population. In addition, we studied the epitope-specific antibody responses were strikingly different and indicated that genetic background influenced the epitope-specific antibody response. Of the serum samples of mice with C57BL and a BALB background, 40 and 17% respectively, were positive in the one of the epitope-specific immunoassays. In contrast to pigs, mice responded predominantly to antigenic domain D and to a lesser degree to antigenic domains E and B. Only few mice had a detectable antibody response against antigenic domains C and A, and none had a detectable antibody response against antigenic domain F.

Glycoprotein E of pseudorabies virus and homologous proteins in other alphaherpesvirinae

This paper reviews biological properties of glycoprotein E (gE) of pseudorabies virus (Aujeszky's disease virus) and homologous proteins in other alphaherpesvirinae. It focuses on the gene encoding gE, conserved regions in the gE protein and its homologs, the complex of gE and gI, biological functions of gE in vitro and in vivo, the role of gE in latency and the role of gE in the induction of humoral and cellular immune responses. Special emphasis is placed on the use of gE as a marker protein in the control and eradication of pseudorabies virus.

Accuracy of fatal motorcycle-injury reporting on death certificates

This study identifies differences in motorcycle injury fatality statistics gathered from different sources. Police Accidents Reports (PARs), identifying fatal motorcycle injuries occurring in Connecticut during 1987 were matched with state death certificates. Matched death certificates were analyzed in three major areas: content, coding, and motorcycle fatality reporting. Death certificates underreported motorcycle fatalities by 38% compared to PARs. Forty percent of death certificates were missing some or all of the required information: 7 did not include the word motorcycle, 18 did not contain acceptable ICD-9 terminology for a motorcyclist, and 17 did not describe how the injury occurred. Forty-one percent of death certificates contained external cause of injury code (E-code) errors. Incomplete information on death certificates was responsible for 52% of inaccurate reporting and E-code errors for 48%. The accuracy of fatal motorcycle injury cause of death reporting on death certificates could be improved by better physician training and rapid implementation of both the computerized death certificate coding systems and upcoming ICD-10 classification system.

Abnormalities of fibrillin in acquired cutis laxa

BACKGROUND

Degeneration of elastic tissue in acquired cutis laxa has been previously described, but microfibrils have not been adequately studied.

OBJECTIVE

We determined whether the microfibrillar component of elastic tissue is affected in skin of a patient with acquired cutis laxa.

METHODS

Lesional skin was examined with indirect immunofluorescence and immunoelectron microscopy with antibodies to fibrillin.

RESULTS

Indirect immunofluorescence showed a reduction in the distribution of fibrillin in the papillary dermis, where there was loss of the usual pattern of microfibrils perpendicular to the epidermis. Immunoelectron microscopy showed a typical distribution of elastic microfibrils around elastin of normal skin. In skin affected by cutis laxa microfibrils appeared morphologically normal but appeared less frequently in selected sites.

CONCLUSION

The microfibrillar component of elastic fibers was reduced in the papillary dermis of this patient with acquired cutis laxa.

Advances in specific therapy for multiple sclerosis

During the past year, two new agents have been demonstrated to be of value in multiple sclerosis. The first agent, a form of recombinant interferon beta (Betaseron; Berlex Labs, Cedar Knolls, NJ), is effective in reducing relapses and also prevent accumulation of brain lesions over time, but has no demonstrated effect on the accumulation of disability over time. The second agent, methylprednisolone (Solumedrol; The Upjohn Co., Kalamozoo, MI), administered in megadose pulses over several days and followed by an oral prednisone taper, reduces the conversion rate of patients with optic neuritis to multiple sclerosis by approximately 50% over 2 years compared with placebo or oral prednisone alone. The mechanisms by which these agents exert their benefits are incompletely understood, but both have complex, relatively widespread effects on the immune systems. The demonstration of efficacy for both of these agents represent landmarks in the search for an effective treatment for multiple sclerosis; both agents seem to provide prophylaxis against future relapses, and methylprednisolone seems to delay the development of the disease. Their introduction into the clinical environment will undoubtedly have a profound effect on the day-to-day care of multiple sclerosis patients as well as the designs of future basic and clinical research. Other new therapies that have substantial potential for benefit in multiple sclerosis but require further definitive study include intramuscular copolymer 1 for relapsing disease and low-dose oral methotrexate and booster doses of intravenous cyclophosphamide for chronic progressive disease.

Spontaneous palpebromandibular synkinesia: a localizing clinical sign

In the classical corneomandibular reflex (CMR), corneal stimulation elicits a bilateral eyelid blink and a brisk anterolateral jaw movement. We here describe 14 patients with a spontaneous palpebromandibular (eyelid-jaw) synkinesia (SPMS) in whom jaw movements, similar to those in CMR, regularly accompanied spontaneous eye blinks without an external corneal stimulus. Eleven of the patients with SPMS also had CMRs on corneal stimulation. Four patients had clinical and imaging evidence of brainstem lesions above the mid-pons, 5 patients had autopsy or imaging evidence of both bilateral cerebral and upper brainstem lesions, and 5 patients had clinical or imaging evidence of bilateral cerebral dysfunction. Topical corneal anesthesia administered to patients who had both CMR and SPMS blocked the CMR but had no effect on the SPMS. In patients with both SPMS and CMR, measurements of latency from onset of orbicularis oculi electromyographic activity to onset of lateral pterygoid EMG activity, and mandibular kinesiography of jaw velocity and direction showed that the eyelid-jaw synkinesias of CMR and SPMS had similar characteristics. We conclude that SPMS is pathophysiologically the same as the eyelid-jaw synkinesia of CMR and both synkinesias originate centrally, probably in the pons. In CMR, the jaw movement is primarily related to the blink rather than the corneal stimulus, but corneal stimulation may be necessary to overcome a higher threshold for expression of the synkinesia than in patients with SPMS. Like CMR, SPMS emerges in patients with upper brainstem or bilateral cerebral lesions and SPMS may therefore be a useful localizing clinical sign.

Deleting two amino acids in glycoprotein gI of pseudorabies virus decreases virulence and neurotropism for pigs, but does not affect immunogenicity

The virulence, pathogenicity and immunogenicity of two pseudorabies virus (PRV) variants were investigated in 3-week-old pigs that had been intranasally infected. Variant M303 (delta 125,126) lacked amino acids valine (125) and cysteine(126) in an immunodominant antigenic region of glycoprotein I (gI) containing two discontinuous antigenic domains, whereas M304 (delta 59,60) lacked amino acids glycine(59) and aspartic acid(60) in a continuous antigenic domain. M303 (delta 125,126) was not virulent for pigs, but M304 (delta 59,60) was as virulent as wild-type PRV: all pigs died within 8 days of infection. Both gI mutant viruses replicated in the oropharyngeal mucosa, although M304 (delta 59,60) replicated to higher virus titres than M303 (delta 125,126), and virus was recovered from various tissues. However, in contrast to M304 (delta 59,60), M303 (delta 125,126) was not recovered from any central nervous system (CNS) tissues examined. Thus, the tendency of PRV to locate in the CNS was markedly reduced by deleting amino acids valine(125) and cysteine(126) of gI. Pigs immunized with M303 were completely protected against challenge infection; no clinical signs of disease were detected, no virus was shed, and no secondary antibody response was detected. Thus, deleting amino acids valine(125) and cysteine(126) in gI decreases virulence and neurotropism and does not affect immunogenicity.

Collagen fibrillogenesis in a three-dimensional fibroblast cell culture system

The purpose of this study was to follow collagen fibril formation in a newly developed three dimensional cell culture system. Human neonatal foreskin fibroblasts were grown on a nylon mesh in Dulbecco's Modified Eagles Medium (DMEM) supplemented with 10% fetal calf serum and antibiotics. Fibrillogenesis was initiated by the addition of 50 micrograms/ml ascorbate to confluent cultures. Sample meshes were processed for electron microscopy or immuno-electron microscopy. Fibrils approximately 20-30 nm in diameter, with 67 nm periodicity, were first detected five days after the addition of ascorbate. As cultures progressed, cells organized into parallel layers between which collagen fibers continued to form and increase in diameter. By day 50, fiber diameter ranged from 30 to 80 nm and large bundles were seen. No collagen fibril formation occurred in control cultures to which no ascorbate was added. However, large amounts of microfibrils were observed. Antibodies against the aminopropeptide of type I procollagen were found to bind to fibrils with diameters less than 34 nm while antibodies against the aminopropeptide of type III collagen bound primarily to fibers which ranged from 35-54 nm in diameter. We believe that this system, which morphologically resembles a normal dermis, will serve as an excellent model for the study of collagen fibrillogenesis.

Deleting valine-125 and cysteine-126 in glycoprotein gI of pseudorabies virus strain NIA-3 decreases plaque size and reduces virulence in mice

We investigated the function of antigenic domains on gI in virulence and immunogenicity. Three PRV gI mutants were constructed by deleting nucleotides coding for the following amino acids: valine-125 and cysteine-126, located in a discontinuous antigenic domain (M 303); glycine-59 and aspartic acid-60 located in a continuous antigenic domain (M304); and arginine-67 and alanine-68, located in a discontinuous antigenic domain (M305). Mismatch primers in the polymerase chain reaction were used to introduce the deletions. Anti-gI monoclonal antibodies were used in an immunoperoxidase monolayer assay to distinguish PRV gI mutants from wild-type PRV. The gI mutant viruses were tested for their growth in vitro and for their virulence in mice. The growth properties of PRV gI mutant virus M303 were comparable to the growth properties of a PRV gI-negative mutant (M301): both mutants produced small plaques in various cells, and when grown on swine kidney cells and chicken embryo fibroblasts, their growth was disadvantaged compared to wild-type PRV. However, in embryonal Balb/c mouse cells expressing gI, gI mutant viruses and wild-type PRV produced plaques of the same size, confirming that the mutations in gI are responsible for the small plaque phenotype. The growth properties of PRV gI mutant viruses M 304 and M 305 were comparable to the growth properties of wild-type PRV. When the mean time to death was used as the criterion, the gI mutant viruses M 301 and M 303 were significantly less virulent in mice than wild-type PRV. Four other, independently obtained, PRV mutants all carrying the valine-125 and cysteine-126 deletion (M 308, M 309, M 310 and M 311 respectively) exhibit the same phenotype. Our results show that deleting valine-125 and cysteine-126 in gI decreases plaque size and reduces virulence in mice to the same degree as deleting the gI protein.

Circulating CD3+ CD4+ CD8+ T lymphocytes in multiple sclerosis

Triple-antibody flow cytometry was used to search for distinctive populations of peripheral blood lymphocyte immunophenotypes in multiple sclerosis (MS). Using monoclonal antibodies to the cell surface markers CD3, CD4, and CD8, T cell subsets were quantified on a cohort of 31 MS patients (not treated with corticosteroids for at least 6 months), 30 healthy donors, and 14 patients with other autoimmune diseases (also corticosteroid treatment-free for at least 6 months). Untreated MS patients displayed a significantly greater population of CD3+CD4+CD8+ circulating T cells than healthy donors (P = 0.023). Patients with other autoimmune diseases displayed mean populations of CD3+CD4+CD8+ cells greater than normal donors and less than MS, but not significantly different from either. An additional 45 MS patients who had received corticosteroid therapy within the previous 6 months were phenotyped. Treatment of symptomatic MS with corticosteroids was associated with a smaller population of circulating CD3+CD4+CD8+ cells. Some MS patients have significantly greater numbers of peripheral blood T lymphocytes simultaneously expressing CD3, CD4, and CD8 surface markers than healthy donors and this population of cells may be reduced by corticosteroids treatment. This triple positive phenotype may be a manifestation of a systemic immune abnormality in MS.

Culturing keratinocytes and fibroblasts in a three-dimensional mesh results in epidermal differentiation and formation of a basal lamina-anchoring zone

The purpose of this study was to characterize an in vitro co-culture model in which fibroblasts grown in a three-dimensional nylon mesh were recombined with human keratinocytes. The cultures were kept for 3 and 5 weeks and then processed for electron microscopy. Keratinocytes showed reconstruction of an epidermis consisting of a basal layer with hemidesmosomes, a stratified epithelium with tonofilaments and desmosomes, a granular layer with keratinosomes and keratohyaline granules, and a transitional stratum corneum. Anchoring filaments, lamina densa, anchoring fibrils, bundles of elastin-associated microfibrils (diameters 10 nm) and fine collagen fibrils were formed. Collagen fibrils near the epidermis were much thinner than those in the lower levels. The present study shows that the dermal model containing metabolically active fibroblasts in their natural environment will support epidermal morphogenesis and differentiation including the formation of a basal lamina and anchoring zone.

Immunochemical analysis of human kidney reticulin

This study characterized the nature of reticulin fibrils from human kidney cortex by immunochemical analysis. Controls consisted of type I collagen fibrils derived from the kidney parietal capsule. Most of the fibrils in the capsule ranged in diameter from 60 to 80 nm whereas reticulin fibrils from the cortex ranged from 30-45 nm. Immunochemistry by light and electron microscopic examinations was carried out with antibodies directed against type I and type III collagens, their corresponding aminopropeptides, and decorin (PG-II). The ratio of type I to type III collagen was determined by cyanogen bromide peptide digests. This study showed that reticulin fibrils are hybrids of type I and type III collagens. Double immunoelectron microscopic examination showed that fibrils 20-25 nm consisted mainly of type I collagen some of which retained their aminopropeptide. Larger fibrils 30-35 nm labeled simultaneously for type I and type III collagens. However, most fibrils with diameters between 40-55 nm labeled for type III collagen and its corresponding aminopropeptide. No decorin was detected at the surface of reticulin fibrils. Purified reticulin consisted of 82% type III and 18% type I collagen whereas collagen derived from the capsule revealed 76% type I and 24% type III. The presence of the aminopropeptide of type III procollagen in reticulin fibrils is a striking feature and may play a role in regulating their diameter.

A population-based study of motorcycle injury and costs

STUDY OBJECTIVE

To provide a population-based injury and cost profile for motorcycle injury in Connecticut.

DESIGN

Population-based retrospective epidemiologic review of Connecticut death certificates, hospital discharge data, and police accident reports.

RESULTS

Connecticut death certificates identified 112 deaths from motorcycle injuries for an annual death rate of 1.2 per 100,000 persons. Death rates were highest among 20- to 24-year-old men. Nonhelmeted motorcyclists were 3.4-fold more likely to die than were helmeted riders (P less than .05). An estimated 2,361 motorcycle-related hospital discharges resulted in an annual hospitalization rate of 24.7 per 100,000 persons. Head, neck, and spinal injuries accounted for 22% of all injuries. Total costs exceeded $29 million; 29% of hospitalized patients were uninsured, and 42% of the cost was not reimbursed to the hospitals.

CONCLUSION

Motorcycle injuries contribute significantly to Connecticut's mortality, morbidity, and medical costs. Our study suggests that a uniform helmet law would save an estimated ten lives and prevent more than 90 nonfatal injuries in Connecticut each year at a cost savings to the state of $5.1 million. These data are crucial in advocating re-enactment of motorcycle helmet laws.

Selective paralysis of voluntary but not limbically influenced automatic respiration

We describe a patient in whom a discrete infarction of the ventral basis pontis caused a complete loss of voluntary respiration, while automatic respiration remained intact. Respiratory excursions, quantified title volumes, and ventilatory response to carbon dioxide were normal, but the patient could not volitionally modify any respiratory parameters. Emotional stimuli producing laughter, crying, or anxiety appropriately modulated automatic respiration. This case established that pathways subserving limbic modulation of automatic respiration descend in the pontine tegmentum and/or lateral portion of the basis pontis spared by this lesion. Furthermore, descending limbic influences on automatic respiration are anatomically and functionally independent of the voluntary respiratory system.

Elastin-associated microfibrils (10 nm) in a three-dimensional fibroblast culture

The purpose of this study is to present a three-dimensional dermal fibroblast model. Skin fibroblasts cultured in this system deposit large amounts of collagen and microfibrils. Fibroblasts were seeded onto a nylon filtration mesh and incubated in the presence or absence of ascorbic acid. Collagen fibril formation was found in the presence of ascorbic acid whereas microfibril formation was seen independent of ascorbic acid supplementation. Immunoelectron microscopy revealed that microfibrils were labeled with fibrillin at 67 nm periodicity. Isolated microfibrils studied by rotary shadowing had a beaded appearance consisting of beads linked to each other by a filamentous structure. The spaces between the beads ranged from 10.00-33.33 nm, suggesting that these microfibrils may have an extension-contraction mechanism. Furthermore, the size and spacing of the beads were similar to that seen in microfibrils from tissues (measured after rotary shadowing). Fibroblasts cultured in a three-dimensional mesh represent an effective in vitro model with which to study microfibril formation.

A randomized trial of replacement antioxidant vitamin therapy for neutrophil locomotory dysfunction in blunt trauma

Studies in patients with serious trauma indicate that the observed neutrophil (PMN) locomotory dysfunction is partly the result of auto-oxidation as shown by evidence of preactivation, diminished reducing capacity, and low serum and cellular ascorbic acid and alpha-tocopherol. To investigate whether replacement of the antioxidant vitamins ascorbic acid and alpha-tocopherol can improve the PMN locomotory defect, ascorbic acid, alpha-tocopherol, ascorbic acid and alpha-tocopherol, or placebo was administered to a total of 46 victims of blunt trauma. PMN locomotion was quantitated using a micropore filter assay. Locomotion data were analyzed by repeated measures analysis with a split plot design and data for days 2-6 after injury were compared. Compared with placebo, the antioxidants improved PMN locomotion. The mean differences in distance migrated (treated minus placebo) were ascorbic acid and alpha-tocopherol = 11.3 +/- 3.0 microns (one-tailed p = 0.001) (mean +/- SE); ascorbic acid = 4.7 +/- 3.4 microns (p = 0.19); and alpha-tocopherol = 3.3 +/- 2.9 microns (p = 0.27). Although both antioxidants given together produced the best results, a plot of the 95% confidence intervals indicates that ascorbic acid and alpha-tocopherol, either given alone, were also better than placebo. We conclude that antioxidant replacement therapy significantly improves the PMN locomotory abnormality in blunt trauma.

A baboon model for in vivo assessment of mucociliary lung clearance

A suitable baboon model (Papio ursinus) for assessing inhibitory effects on mucociliary lung clearance was required. Clearance of various dimensions of nebulized particles (99mTc-labelled) was monitored with the animals (n = 6) under either ketamine or pentobarbitone anaesthesia. The best prospect of substantial and reproducible clearance in spite of the inhibition by the anaesthesia were obtained with pentobarbitone, and using nebulized radiolabelled particles of diameter range between 10 and 45 microns, thus avoiding trapping in the non-ciliary alveoli.

Prostaglandin E1 and papaverine: a comparative study on the ability to increase the penile bloodpool as measured by the 99mTc-penogram in the baboon model

The evaluation of arterial blood supply and venous drainage of the penis is essential in assessing the impotent male. The vaso-active drugs prostaglandin E1 and papaverine, as intracavernous injections, cause penile erections in humans by influencing the arterial blood supply and venous drainage. These drugs were used in the normal baboon and in vascular compromised baboons using a 99mTc-penogram to quantify the vascular status of the penis. Ligation of the A. Iliaca Interna was performed to change the penile blood supply, thus compromising the vascular supply. It was observed that pre- and post-operatively, the increase in the penile bloodpool was more dramatic although not significantly so (P less than 0.05), but more variable after papaverine than with prostaglandin E1. The effect was even more enhanced (P less than 0.05) in the vascular compromised baboons so that the occurrence of priapism after papaverine can speculatively not be excluded. Also the more consistent vasoactive response after prostaglandin E1 seems to establish it as the superior intracavernous injectable agent.

Extracellular microfibrils are increased in localized and systemic scleroderma skin

Extracellular microfibrils, about 10 nm thick with a hollow core have been found in most organs as free bundles or in association with elastic fibrils. Histochemistry of the dermis of 4 patients with localized and 6 with systemic scleroderma revealed numerous fine elastic fibrils in areas of fibrosis. Immunofluorescence and immunoelectron microscopy were performed with antibodies against fibrillin and amorphous elastin. The lower dermis revealed an increase in 10-nm microfibrils interspersed between collagen fibrils. These microfibrils stained for fibrillin but not for amorphous elastin. Fibrosis in localized and systemic scleroderma involves the deposition of collagen fibrils and microfibrils.

Bronchial hyperresponsiveness in normal subjects during attenuated influenza virus infection

Fourteen healthy male subjects with hemagglutination-inhibition antibody titers of 1:8 or less to homologous influenza A virus were studied. Six subjects received live, attenuated influenza virus by nasal drops and by aerosol. Although infection occurred in these six subjects, with the development of 4-fold or greater increases in hemagglutination-inhibition antibody titers, they remained asymptomatic. Eight subjects received placebo via the same route, and did not develop symptoms and showed no increase in antibody titer. Prior to administration of virus or placebo, histamine diphosphate aerosol increased airway resistance only slightly, and there was no difference between the virus and placebo groups. Two days after inoculation, bronchomotor responses in the placebo group were unchanged (p greater than 0.05), but in the virus-infected group, bronchomotor responses were significantly greater than in the preinfected state (p less than 0.01). Isoproterenol hydrochloride reversed and prevented the increase in airway resistance after histamine, suggesting that the bronchoconstriction was caused by smooth muscle contraction. Our findings indicate that transient, asymptomatic respiratory virus infection augments airway smooth muscle responses.

Decorin interacts with fibrillar collagen of embryonic and adult human skin

Biglycan (PG-I, BGN) and decorin (PG-II, DCN) are small proteoglycans that have been isolated in cartilage, skin, and bone. Although the function of biglycan is unknown, there is biochemical evidence that decorin interacts with fibrillar collagens (type I, type II). The purpose of this study was to perform immunofluorescence and immunoelectron microscopy and immunoblotting of human embryonic and adult skin with antibodies directed against biglycan and decorin. These antibodies were developed against synthetic peptides of the core proteins of biglycan (amino acid sequence 11-24) and decorin (amino acid sequence 5-17). Immunofluorescence microscopy showed that decorin stained embryonic and adult collagen fibrils. Biglycan did not stain collagen, but it appeared to stain the pericellular matrix of embryonic mesenchymal cells. Immunoelectron microscopy revealed labeling of all collagen fibrils with decorin antibodies regardless of their diameter, often at 60-nm periodicity. Positive stains suggest that most of the labeling was in the gap of the D-period (d and e bands) and also in one of the steps (c band). Decorin was identified by immunoblotting in fetal and adult skin. Also, significant amounts of core protein was identified lacking the dermatan sulfate chain. This study suggests that the core protein of decorin interacts with collagen fibrils although its specific function remains unknown.

Quantitative evaluation of the penile vascular status by means of the 99mTc-penogram in conjunction with either papaverine or prostaglandin E1 in the anaesthetised baboon model

The evaluation of both the arterial blood supply and the venous drainage of the penis is essential in the assessment of the impotent male. The vasoactive drugs papaverine and prostaglandin E1, as intracavernous injections, cause penile erections by influencing arterial blood supply and venous drainage. These drugs were used in a baboon model together with a 99mTc-penogram to provide information on the vascular status of the penis. An increase in penile blood pool was observed, more dramatic and rapid after administration of papaverine. A quantitative assessment of the vascular status seems possible and will next be monitored in a vascular-compromised baboon for purposes of clinical application.