Phytodetoxification of TNT by transgenic plants expressing a bacterial nitroreductase

There is major international concern over the wide-scale contamination of soil and associated ground water by persistent explosives residues. 2,4,6-Trinitrotoluene (TNT) is one of the most recalcitrant and toxic of all the military explosives. The lack of affordable and effective cleanup technologies for explosives contamination requires the development of better processes. Significant effort has recently been directed toward the use of plants to extract and detoxify TNT. To explore the possibility of overcoming the high phytotoxic effects of TNT, we expressed bacterial nitroreductase in tobacco plants. Nitroreductase catalyzes the reduction of TNT to hydroxyaminodinitrotoluene (HADNT), which is subsequently reduced to aminodinitrotoluene derivatives (ADNTs). Transgenic plants expressing nitroreductase show a striking increase in ability to tolerate, take up, and detoxify TNT. Our work suggests that expression of nitroreductase (NR) in plants suitable for phytoremediation could facilitate the effective cleanup of sites contaminated with high levels of explosives.

Abdominal vascular injuries: injuries to the aorta

This article discusses injuries to the abdominal aorta at its supra- and infrarenal positions, focusing on the surgical approaches to abdominal aorta injuries and renal vascular pedicles. The controversy regarding the use of bioprosthetic materials and the coLlective experience with these injuries as reported in the literature are reviewed. Primary renal artery repair versus nephrectomy also is examined.

The role of thyroid hormone administration in potential organ donors

HYPOTHESIS

Levothyroxine sodium therapy should be used in brain-dead potential organ donors to reverse hemodynamic instability and to prevent cardiovascular collapse, leading to more available organs for transplantation.

DESIGN

Prospective, before and after clinical study.

SETTING

A surgical intensive care unit of an academic county hospital.

PATIENTS

During a 12-month period (September 1, 1999, through August 31, 2000), we evaluated 19 hemodynamically unstable patients with traumatic and nontraumatic intracranial lesions, who were candidates for organ donation following brain death declaration.

INTERVENTIONS

All patients were resuscitated aggressively for organ preservation by fluids, inotropic agents, and vasopressors. If, despite all measures, the patients remained hemodynamically unstable, a bolus of 1 ampule of 50% dextrose, 2 g of methylprednisolone sodium succinate, 20 U of insulin, and 20 microg of levothyroxine sodium was administered, followed by a continuous levothyroxine sodium infusion at 10 microg/h.

RESULTS

There was a significant reduction in the total vasopressor requirement after levothyroxine therapy (mean +/- SD, 11.1 +/- 0.9 microg/kg per minute vs 6.4 +/- 1.4 microg/kg per minute, P =.02). Ten patients (53%) had complete discontinuation of vasopressors. There were no failures to reach organ donation due to cardiopulmonary arrest.

CONCLUSIONS

Levothyroxine therapy plays an important role in the management of hemodynamically unstable potential organ donors by decreasing vasopressor requirements and preventing cardiovascular collapse. This may result in an increase in the quantity and quality of organs available for transplantation.

Noninvasive measurement of gastric accommodation in patients with idiopathic nonulcer dyspepsia

OBJECTIVES

Postprandial symptoms are associated with impaired postprandial gastric accommodation. The aims of this study were to apply a noninvasive method to measure accommodation of the entire stomach in healthy subjects and in patients with idiopathic dyspeptic symptoms, and to assess the frequency of abnormal gastric accommodation and emptying of solids in these patients.

METHODS

In 20 healthy volunteers and 32 tertiary referral patients, we used i.v. 99mTc-single photon emission computed tomography (SPECT) to measure fasting and postprandial gastric volumes; we expressed the volume response to feeding ("accommodation") as the change in gastric volume and the ratio of postprandial/fasting volumes. The stomach was identified in transaxial SPECT tomographic images using a semiautomated, intensity-based extraction algorithm. Whole gastric volumes were measured using AnalyzeAVW software. Gastric emptying in patients was measured by scintigraphy. We also assessed dyspeptic symptoms and the association with normal or reduced accommodation.

RESULTS

SPECT imaging detects the postprandial change in gastric volume ("accommodation") in health and disease. Among healthy subjects (eight men, 12 women), the postprandial/fasting gastric volume ratio was 4.9+/-1.7 (mean +/- SD; fifth through 95th percentiles 3-8, median 4.6). Thirteen (41%) patients with idiopathic nonulcer dyspepsia had reduced postprandial "accommodation." Gastric emptying was fast in four (13%), normal in 25 (78%), and slow in three (9%) patients. Both tests were normal in 50% of patients. Weight loss of >10 pounds tended to be more frequently observed in those with reduced "accommodation" (62% vs 32%, p = 0.09).

CONCLUSIONS

SPECT imaging noninvasively measures fasting and postprandial gastric volumes in humans. Half the patients with idiopathic nonulcer dyspepsia had impaired gastric accommodation or emptying. Reduced gastric "accommodation" was observed in 41% of a group with idiopathic nonulcer dyspepsia. Abnormal gastric emptying is less frequent (22%).

Diagnostic approach to a patient with suspected celiac disease: a cost analysis

Serological testing is an important tool in the diagnostic work-up of suspected celiac disease. Our aim was to apply a decision analysis model to compare the costs of serological testing versus small bowel biopsy in the diagnostic work-up of celiac disease. A cost-minimization approach was employed. A decision analysis model with three diagnostic arms was designed using Data Version 3.5: anti-gliadin antibody versus endomysial antibody versus small bowel biopsy. Response to gluten-free diet was considered diagnostic of celiac disease; lack of response prompted a small bowel biopsy to definitively exclude celiac disease. Baseline probabilities were varied using sensitivity analysis. Sensitivity analysis revealed that the endomysial antibody strategy was least costly, provided the prevalence of celiac disease was less than 42%; above this anti-gliadin antibody became the most economical option. In conclusion, initial screening with endomysial antibody is the least costly strategy for diagnosing celiac disease in a low risk population. Antigliadin antibody becomes the cheaper strategy for higher risk populations.

Is there a role for gastric accommodation and satiety in asymptomatic obese people?

OBJECTIVE

The relationships of gastric accommodation and satiety in moderately obese individuals are unclear. We hypothesized that obese people had increased gastric accommodation and reduced postprandial satiety. The objective of this study was to compare gastric accommodation and satiety between obese and non-obese asymptomatic subjects.

RESEARCH METHODS AND PROCEDURES

In 13 obese (body mass index [BMI] > or = 30 kg/m(2); mean BMI, 37.0 +/- 4.9 kg/m(2)) and 19 non-obese control subjects (BMI < 30 kg/m(2); mean BMI, 26.2 +/- 2.9 kg/m(2)), we used single photon emission computed tomography to measure fasting and postprandial gastric volumes and expressed the accommodation response as the ratio of postprandial/fasting volumes. The satiety test measured maximum tolerable volume of ingestion of liquid nutrient meal (Ensure) and symptoms 30 minutes after cessation of ingestion.

RESULTS

Total fasting and postprandial gastric volumes and the ratio of postprandial/fasting gastric volume were not different between asymptomatic obese and control subjects. However, the fasting volume of the distal stomach was greater in obese than in control subjects. Maximum tolerable volume of ingested Ensure and aggregate symptom score 30 minutes later were also not different between obese and control subjects.

DISCUSSION

Asymptomatic obese individuals (within the BMI range of 32.6 to 48 kg/m(2)) did not show either increased postprandial gastric accommodation or reduced satiety. These data suggest that gastric accommodation is unlikely to provide an important contribution to development of moderate obesity.

Healing of traumatic diaphragm injuries: comparison of laparoscopic versus open techniques in an animal model

BACKGROUND

Minimally invasive surgical techniques have become routinely applied to the evaluation and treatment of patients with isolated diaphragmatic injuries due to penetrating trauma. The objective of the study was to compare the healing of diaphragm injuries as determined by macroscopic inspection, histologic appearance, and tensile strength following repair by open suturing, laparoscopic suturing, and laparoscopic stapling techniques in an animal model.

METHODS

Using a pig model, three injuries were created and repaired in each hemidiaphragm of five animals, for a total of 30 lacerations. These injuries were repaired using single-layer open repair, single-layer laparoscopic repair, or laparoscopic stapling. After a 6-week healing period the animals were sacrificed. The gross integrity, histologic appearance using H+E and trichrome satins, and tensile strength of each repair were assessed.

RESULTS

All injuries were grossly intact without dehiscence or herniation. Histologic examination revealed no difference in the collagen deposition between the three groups. The tensile strengths of each type of repair were similar.

CONCLUSION

Laparoscopic techniques used to repair diaphragmatic injuries allow for adequate healing equivalent to open sutured repairs. Simple approximation of the peritoneum with laparoscopic staples allows full-thickness healing of these injuries.

Old age as a criterion for trauma team activation

BACKGROUND

Elderly trauma patients have been shown to have a worse prognosis than young patients. Age alone is not a criterion for trauma team activation (TTA). In the present study, we evaluated the role of age > or = 70 years as a criterion for TTA.

METHODS

The present study was a trauma registry study that included injured patients 70 years of age or older. Patients who died in hospital, were admitted to the intensive care unit (ICU) within 24 hours, or had a non-orthopedic operation were assumed to benefit from TTA.

RESULTS

During a 7.5-year period, 883 elderly (> or = 70 years) trauma patients meeting trauma center criteria were admitted to our center. Overall, 223 patients (25%) met at least one of the standard TTA criteria. The mortality in this group was 50%, the ICU admission rate was 39%, and a non-orthopedic operation was required in 35%. The remaining 660 patients (75%) did not meet standard TTA criteria. The mortality was 16%, the need for ICU admission was 24%, and non-orthopedic operations were required in 19%. Sixty-three percent of patients with severe injuries (Injury Severity Score > 15) and 25% of patients with critical injuries (Injury Severity Score > 30) did not have any of the standard hemodynamic criteria for TTA.

CONCLUSION

Elderly trauma patients have a high mortality, even with fairly minor or moderately severe injuries. A significant number of elderly patients with severe injuries do not meet the standard criteria for TTA. It is suggested that age > or = 70 years alone should be a criterion for TTA.

Selective nonoperative management in 1,856 patients with abdominal gunshot wounds: should routine laparotomy still be the standard of care?

OBJECTIVE

To evaluate the safety of a policy of selective nonoperative management (SNOM) in patients with abdominal gunshot wounds.

SUMMARY BACKGROUND DATA

Selective nonoperative management is practiced extensively in stab wounds and blunt abdominal trauma, but routine laparotomy is still the standard of care in abdominal gunshot wounds.

METHODS

The authors reviewed the medical records of 1,856 patients with abdominal gunshot wounds (1,405 anterior, 451 posterior) admitted during an 8-year period in a busy academic level 1 trauma center and managed by SNOM. According to this policy, patients who did not have peritonitis, were hemodynamically stable, and had a reliable clinical examination were observed.

RESULTS

Initially, 792 (42%) patients (34% of patients with anterior and 68% with posterior abdominal gunshot wounds) were selected for nonoperative management. During observation 80 (4%) patients developed symptoms and required a delayed laparotomy, which revealed organ injuries requiring repair in 57. Five (0.3%) patients suffered complications potentially related to the delay in laparotomy, which were managed successfully. Seven hundred twelve (38%) patients were successfully managed without an operation. The rate of unnecessary laparotomy was 14% among operated patients (or 9% among all patients). If patients were managed by routine laparotomy, the unnecessary laparotomy rate would have been 47% (39% for anterior and 74% for posterior abdominal gunshot wounds). Compared with patients with unnecessary laparotomy, patients managed without surgery had significantly shorter hospital stays and lower hospital charges. By maintaining a policy of SNOM instead of routine laparotomy, a total of 3,560 hospital days and $9,555,752 in hospital charges were saved over the period of the study.

CONCLUSION

Selective nonoperative management is a safe method for managing patients with abdominal gunshot wounds in a level 1 trauma center with an in-house trauma team. It reduces significantly the rate of unnecessary laparotomy and hospital charges.

Spherocytosis preceding the development of myelodysplasia

We report two patients with prominent spherocytosis in the peripheral blood who later went on to develop myelodysplasia. There was no evidence of a myelodysplastic syndrome at the time of presentation. Morphological abnormalities of the peripheral blood along with possible explanations of spherocytosis are discussed.

Cigarette smoking and celiac sprue: a case-control study

OBJECTIVE

Environmental factors other than gliadin exposure and certain HLA haplotypes may play a role in the pathogenesis of celiac disease. Previous studies have suggested a strong inverse relationship between cigarette smoking and celiac disease. We sought to determine the relationship between celiac disease and cigarette smoking in our patient population.

METHODS

All newly diagnosed adults with biopsy-proven celiac disease evaluated at Mayo Clinic Rochester between January 1, 1993, and June 30, 1998, were identified. Three clinic patients who were matched to each case on geographical area of residence, age, gender, and calendar year of visit served as controls. Smoking information was obtained from a standard medical questionnaire that was completed by all clinic patients at the time of registration. The adjusted odds ratio for celiac disease in current and former smokers relative to nonsmokers was estimated with a matched three-to-one conditional logistic regression model.

RESULTS

A total of 82 adults with biopsy-proven celiac disease were identified. At the time of diagnosis, the proportion of current smokers was 10% in cases and 10% in controls, yielding an adjusted odds ratio of 1.5 (95% CI = 0.5-4.3). In all, 34% of cases were former smokers versus 28% of controls, yielding an odds ratio of 1.6 (95% CI = 0.8-3.2).

CONCLUSION

This case-control study was unable to detect an association between cigarette smoking and celiac disease.

Use of montelukast as steroid-sparing agent for recurrent eosinophilic gastroenteritis

Patients with eosinophilic gastroenteritis generally respond well to corticosteroids but relapses are common. Patients with relapsing disease are usually placed on long-term low-dose prednisone or immunosuppressive therapy. Here we reported on a patient with severe steroid-dependent eosinophilic gastroenteritis who was able to successfully taper off steroids and maintain remission after starting montelukast, a leukotriene receptor antagonist. To our knowledge, this is the first use of montelukast as a steroid sparing agent for eosinophilic gastroenteritis.

Cell cycle regulation of cyclin-dependent kinases in tobacco cultivar Bright Yellow-2 cells

Plants possess two major classes of cyclin-dependent kinases (CDK) with cyclin-binding motifs PSTAIRE (CDK-a) and PPTA/TLRE (CDK-b). Tobacco (Nicotiana tabacum L. cv Bright Yellow-2) cells are the most highly synchronizable plant culture, but no detailed analysis of CDK activities has been reported in this system. Here we describe isolation of new PPTALRE CDKs (Nicta;CdkB1) from Bright Yellow-2 cells and present detailed analysis of the mRNA, protein and kinase activity levels of CdkB1, and the PSTAIRE CDKA during the growth and cell cycles. CdkA and CdkB1 transcripts are more abundant in exponential than in stationary phase cells, but the two genes show strikingly different regulation during the cell cycle. CdkA mRNA and protein accumulate during G1 in cells re-entering the cell cycle, and immunoprecipitated histone H1 kinase activity increases at the G1/S boundary. Aphidicolin synchronized cells show the highest CDKA-associated histone H1 kinase activity during S-G2 phases, although CdkA mRNA and protein levels are not significantly regulated. In contrast, CdkB1 transcripts are present at very low levels until S phase and CDKB1 protein and kinase activity is almost undetectable in G1. CdkB1 mRNA accumulates through S until M phase and its associated kinase activity peaks at the G2/M boundary, confirming that transcription of PPTALRE CDKs is cell cycle regulated. We suggest that CDKA kinase activity likely plays roles at the G1/S phase boundary, during S phase, and at the G2/M phase transition, and that CDKB1 kinase activity is present only at G2/M.

Penetrating colon injuries requiring resection: diversion or primary anastomosis? An AAST prospective multicenter study

BACKGROUND

The management of colon injuries that require resection is an unresolved issue because the existing practices are derived mainly from class III evidence. Because of the inability of any single trauma center to accumulate enough cases for meaningful statistical analysis, a multicenter prospective study was performed to compare primary anastomosis with diversion and identify the risk factors for colon-related abdominal complications.

METHODS

This was a prospective study from 19 trauma centers and included patients with colon resection because of penetrating trauma, who survived at least 72 hours. Multivariate logistic regression analysis was used to compare outcomes in patients with primary anastomosis or diversion and identify independent risk factors for the development of abdominal complications.

RESULTS

Two hundred ninety-seven patients fulfilled the criteria for inclusion and analysis. Overall, 197 patients (66.3%) were managed by primary anastomosis and 100 (33.7%) by diversion. The overall colon-related mortality was 1.3% (four deaths in the diversion group, no deaths in the primary anastomosis group, p = 0.012). Colon-related abdominal complications occurred in 24% of all patients (primary repair, 22%; diversion, 27%; p = 0.373). Multivariate analysis including all potential risk factors with p values < 0.2 identified three independent risk factors for abdominal complications: severe fecal contamination, transfusion of > or = 4 units of blood within the first 24 hours, and single-agent antibiotic prophylaxis. The type of colon management was not found to be a risk factor. Comparison of primary anastomosis with diversion using multivariate analysis adjusting for the above three identified risk factors or the risk factors previously described in the literature (shock at admission, delay > 6 hours to operating room, penetrating abdominal trauma index > 25, severe fecal contamination, and transfusion of > 6 units blood) showed no statistically significant difference in outcome. Similarly, multivariate analysis and comparison of the two methods of colon management in high-risk patients showed no difference in outcome.

CONCLUSION

The surgical method of colon management after resection for penetrating trauma does not affect the incidence of abdominal complications, irrespective of associated risk factors. Severe fecal contamination, transfusion of > or = 4 units of blood within the first 24 hours, and single-agent antibiotic prophylaxis are independent risk factors for abdominal complications. In view of these findings, the reduced quality of life, and the need for a subsequent operation in colostomy patients, primary anastomosis should be considered in all such patients.

A novel and highly divergent Arabidopsis cyclin isolated by complementation in budding yeast

A novel cyclin, CycJ18, was isolated by complementation of G1 cyclin-deficient budding yeast with an Arabidopsis cDNA library. CycJ18 shares only 20% identity in its conserved cyclin box domain with other cyclins, and is predominantly expressed in young seedlings. CycJ18 is a member of a potential new plant cyclin class.

Low incidence of Helicobacter pylori infection in patients with duodenal ulcer and chronic liver disease

BACKGROUND

Duodenal ulcer (DU) is a common problem in patients with chronic liver disease (CLD) and with inadequate response to H2 receptor antagonists. Omeprazole might be more effective. In DU-CLD patients, Helicobacter pylori prevalence is low. Nitric oxide is increased in gastric mucosa in cirrhosis. Oxygen-free radicals have a role in gastric inflammation and are abnormal in CLD. Nitrotyrosine is a marker of nitric oxide and oxygen-free radical toxic mucosal reaction.

METHODS

Sixty-nine patients were divided into 2 groups: control (26 patients with DU) and CLD groups (43 patients, DU-CLD). Omeprazole was given (40 mg/day) for 2 or 4 weeks. Symptoms and endoscopy findings were recorded before and after treatment. Antral biopsy specimens were stained for H. pylori and nitrotyrosine.

RESULTS

Clinical features of DU are similar in patients with and without CLD. The main presentation was epigastric pain (70%) and bleeding (23%). Healing rate with omeprazole was higher in DU-CLD patients (90.7%) than in controls (80.8%). H. pylori was much lower in DU-CLD patients (51.2%) than controls (96.2%). Nitrotyrosine staining was negative in normal controls (0%) and positive in control-DU (100%), CLD-H. pylori positive (81%), and CLD-H. pylori negative (91%) cases.

CONCLUSIONS

DU in patients with CLD is not different clinically from those without CLD. Omeprazole effectively and safely treats DU in CLD. Nitric oxide and free oxygen radicals may result in gastric mucosal changes in CLD similar to that caused by H. pylori.

Emergency medical services telephone referral program: an alternative approach to nonurgent 911 calls

OBJECTIVE

To examine the effects of transferring nonurgent 911 calls to a telephone consulting nurse. It was hypothesized that the telephone referral program would result in fewer basic life support (BLS) responses with no adverse patient outcome or decrease in patient satisfaction.

METHODS

A two-phased prospective study was conducted in an urban and rural setting with a population of 650,000. During phase I, a BLS unit was dispatched on all calls and a nurse intervention was simulated. During phase II, no BLS unit was dispatched for calls meeting study criteria. Callers were transferred to the nurse, and consulting nurse protocols were used to direct care. Data were collected from dispatch, BLS, nurse, and hospital records and patient self-assessment.

RESULTS

During phase I, 38 callers were transferred to the consulting nurse with no nurse intervention. During phase II, 133 cases were transferred to the nurse line. There were no adverse outcomes detected. The nurse recommended home care for 31%, physician referral for 24%, referral back to 911 for 17%, community resource for 11%, and other referral for 17%. Nurses contacted 85 patients for telephone follow-up. Ninety-four percent of the patients reported feeling better, 6% felt the same, and none felt worse. Patients were satisfied with the outcome in 96% of the cases.

CONCLUSION

Transferring 911 calls to a nurse line resulted in fewer BLS responses and no adverse patient outcomes, while maintaining high patient satisfaction. Dispatch criteria correctly identified cases with minimal medical needs. A high percentage of the patients reported feeling better after the intervention. This study has major implications for communities interested in efficient use of emergency medical services resources.

Calcification within metastatic pulmonary nodules from synovial sarcoma

A case of calcified metastatic lung deposits from synovial sarcoma of the leg is reported. Calcification within metastatic lung nodules from synovial sarcoma has not been previously reported. The differential diagnoses of calcified lung metastases are presented.

The Arabidopsis D-type cyclins CycD2 and CycD3 both interact in vivo with the PSTAIRE cyclin-dependent kinase Cdc2a but are differentially controlled

D-type cyclins (CycD) play key roles in linking the Arabidopsis cell cycle to extracellular and developmental signals, but little is known of their regulation at the post-transcriptional level or of their cyclin-dependent kinase (CDK) partners. Using new antisera to CycD2 and CycD3, we demonstrate that the CDK partner of these Arabidopsis cyclins is the PSTAIRE-containing CDK Cdc2a. Previous analysis has shown that transcript levels of CycD2 and CycD3 are regulated in response to sucrose levels and that both their mRNA levels and kinase activity are induced with different kinetics during the G(1) phase of cells reentering the division cycle from quiescence. Here we analyze the protein levels and kinase activity of CycD2 and CycD3. We show that CycD3 protein and kinase activity parallel the abundance of its mRNA and that CycD3 protein is rapidly lost from cells in stationary phase or following sucrose removal. In contrast to both CycD3 and the regulation of its own mRNA levels, CycD2 protein is present at constant levels. CycD2 kinase activity is regulated by sequestration of CycD2 protein in a form inaccessible to immunoprecipitation and probably not complexed to Cdc2a.

New perspectives in gastric acid suppression: genetic polymorphisms predict the efficacy of proton pump inhibitors

Proton pump inhibitors are highly effective in the management of acid-peptic diseases. These drugs potently inhibit acid secretion from gastric parietal cells by irreversibly inhibiting activity of the H(+), K(+) ATPase (proton pump). Early studies of the pharmacokinetics of proton pump inhibitors demonstrated considerable variation in drug clearance rates among patients and healthy volunteers. This variation was also reflected in a wide range of the efficacy of acid suppression by standard doses of proton pump inhibitors among study subjects; those with slower clearance and higher drug concentrations experienced superior acid suppression. Proton pump inhibitors are predominantly inactivated by the 2C19 isoform of the hepatic cytochrome P450 mixed function oxidase system. The cytochrome P450 2C19 gene is polymorphic, with three known inactivating mutations. Individuals with one or two mutant cytochrome P450 2C19 alleles metabolize proton pump inhibitors more slowly than those with two wild-type alleles and experience higher drug levels. An individual's cytochrome P450 2C19 genotype predicts the degree of acid suppression in response to a standard dose of a proton pump inhibitor. Emerging data suggests that the clinical effectiveness of proton pump inhibitors in the treatment of acid-peptic diseases may also be dependent on cytochrome P450 2C19 genotype.

Cell cycle controls and the development of plant form

The relationship between cell division and plant form has long been a battleground for the debate between those proclaiming and disclaiming an important role for cell division in morphogenetic and developmental processes. Recent evidence suggests that cell division and morphogenesis are intimately interconnected, and whereas overall architecture is determined by patterning genes, the elaboration and execution of developmental programmes require proper control of the cell-division cycle.

"Insignificant" mechanism of injury: not to be taken lightly

BACKGROUND

Trauma resources should be spent rationally. The mechanism of trauma is used extensively to triage patients to appropriate levels of care. We examine the hypothesis that patients with "insignificant" mechanism of trauma may have major injuries that require expert trauma care.

STUDY DESIGN

Over 9 months at a high-volume Level I trauma center, a prospective study was done on patients who sustained ground-level falls (GLF), low-level falls (LLF) from less than 10 feet, or were found down (FD) with no external evidence of significant trauma, and required evaluation by the trauma team. Of 301 patients included, 110 (37%) had GLF, 95 (31%) LLF, and 96 (32%) FD. Our main outcomes measure was significant injuries, defined as visceral or intracranial injuries, long-bone, pelvic, facial, or spinal fractures.

RESULTS

One hundred ten patients (37%) had significant injuries, 20 (7%) were admitted to the ICU, 14 (5%) required an operation, and 4 (1%) died. The most common injuries were intracranial and skeletal. Almost all patients were evaluated by CT (95%), but only one-quarter had abnormal findings on it. LLF, age more than 55 years, and the absence of severe intoxication (blood alcohol level of less than 200 mg/dL) were independent risk factors for significant injuries. A statistical prediction model showed that, when all risk factors are present, the probability of significant injuries is 73%; when all risk factors are absent, there is still a 16% chance for significant injuries. Patients with significant injuries had more operations, longer hospital stays, and higher hospitalization costs compared with patients without significant injuries.

CONCLUSIONS

Low-energy trauma may produce significant injuries, predominantly intracranial and skeletal. Trauma care providers should be cautious about dismissing such patients based on the trivial mechanism of injury. Patients with LLF who are older than 55 years and not severely intoxicated have a high likelihood for significant injuries. Resources should be spent rationally for patients who do not have these characteristics, because the probability of significant injuries among them is low, but not zero.

Effect of peroxynitrite on motor function of the opossum esophagus

Nitric oxide (NO*) is a mediator of esophageal motility. Esophageal dysmotility accompanies esophagitis. During inflammation, superoxide and NO* form peroxynitrite (ONOO-), a reactive molecule that alters cellular function. We tested the hypotheses that ONOO- affects esophageal motility and is produced in association with esophagitis. Transverse muscle strips from the opossum esophagus were stimulated by an electrical field, and nitrotyrosine immunoblots were performed. Peroxynitrite, its decomposed form, or NaNO2 relaxed the lower esophageal sphincter (LES) and attenuated the off response. These effects were inhibited by oxyhemoglobin (Hgb). An antagonist of guanylate cyclase, 1H[1,2,4]oxadiazole[4,3]quinoxalin-1-one (ODQ), inhibited the LES relaxation produced by ONOO-. Nitrotyrosine, a footprint for ONOO- production, was detected in inflamed esophagus. These studies support the hypotheses that ONOO alters esophageal motor function and is formed in association with esophagitis. It is possible that some of the esophageal motor dysfunction seen with esophagitis may be related to the formation of ONOO-.

Diagnosing gastroesophageal reflux disease

Gastroesophageal reflux disease (GERD) is a common condition with a variety of clinical manifestations and potentially serious complications. This article reviews available methods for diagnosing GERD. A clinical history of the classic symptoms of GERD, heartburn or acid regurgitation, is sensitive enough to establish the diagnosis in patients without other complications. Esophagogastroduodenoscopy is the best way to evaluate suspected complications of GERD, but endoscopic findings are insensitive for the presence of pathological reflux, and therefore they cannot reliably exclude GERD. The "gold standard" study for confirming or excluding the presence of abnormal gastroesophageal reflux is the 24-hour ambulatory esophageal pH monitoring test, and this study should be used for the evaluation of refractory symptoms and extraesophageal manifestations of GERD. A formal acid-suppression test is helpful in the evaluation of the atypical GERD symptom of noncardiac chest pain. Optimal use of currently available tests for GERD may allow for more efficient diagnosis and better characterization of the pathological manifestations associated with GERD.