Air Medical Blood Transfusion as a Trigger of Massive Transfusion Protocol

Air medical services can improve access to blood products at the point of injury. Studies have shown that early activation of mass transfusion protocols (MTPs) can improve the survival of trauma patients by up to 25%. There are several scoring systems to guide early activation, but the use of a single criterion has been elusive. Our study sought to determine if air medical administration of blood products was a risk factor for massive transfusion activation and utilization of prehospital vital signs for calculation of the shock index. In our retrospective study, we evaluated adult trauma patients transfused by helicopter emergency medical services (HEMS) and as a control all patients in our institution receiving the MTP. Our study found HEMS blood transfusion was not a reliable trigger for MTP, although the sample size may have limited our findings. We found that HEMS care resulted in an overall reduction in the volume of transfusion and an improvement in hemodynamic parameters upon trauma center arrival. HEMS transfusion and a higher rate of tranexamic acid administration may have contributed to these findings. Of note, the assessment of blood consumption score and shock index were nonspecific in the study populations.

Trends in Drug Tests among Children: A 22-Year Retrospective Analysis

There are several pathophysiological outcomes associated with substance abuse including metabolic disbalance, neurodegeneration, and disordered redox. Drug use in pregnant women is a topic of great concern due to developmental harm which may occur during gestation and the associated complications in the neonate after delivery. We sought to determine what the trajectory of drug use is like in children aged 0-4 years and mothers of neonates. Urine drug screen (UDS) results were obtained of our target demographic during 1998-2011 and 2012-2019 from LSU Health Sciences Center in Shreveport (LSUHSC-S). Statistical analysis was performed using R software. We observed an increase in cannabinoid-positive UDS results in both Caucasian (CC) and African American (AA) groups between 1998-2011 and 2012-2019 periods. Cocaine-positive UDS results decreased in both cohorts. CC children had higher UDS positive results for opiates, benzodiazepines, and amphetamines, while AA children had a higher percentage for illicit drugs such as cannabinoids and cocaine. Neonate's mothers had similar UDS trends to that in children during 2012-2019. Overall, while percentage of positive UDS results for both AA and CC 0-4 year old children started to decline for opiate, benzodiazepine, and cocaine during 2012-2019, cannabinoid- and amphetamine (CC)-positive UDS steadily increased. These results suggest a shift in the type of drug use by mothers from opiates, benzodiazepines, and cocaine to cannabinoids and/or amphetamines. We also observed that 18-year-old females who tested positive for opiates, benzodiazepine, or cocaine had higher than average chances of testing positive for cannabinoids later in life.

Improved Healthcare Access Reduces Requirements for Surgery in Indigent IBD Patients Using Biologic Therapy: A 'Safety-Net' Hospital Experience

Low socioeconomic status (SES) is associated with greater morbidity and increased healthcare resource utilization (HRU) in IBD. We examined whether a financial assistance program (FAP) to improve healthcare access affected outcomes and HRU in a cohort of indigent IBD patients requiring biologics. IBD patients (>18 years) receiving care at a ‘safety-net’ hospital who initiated biologics as outpatients between 1 January 2010 and 1 January 2019 were included. Patients were divided by FAP status. Patients without FAP had Medicare, Medicaid, or commercial insurance. Primary outcomes were steroid-free clinical remission at 6 and 12 months. Secondary outcomes were surgery, hospitalization, and ED utilization. Multivariate logistic regression was used to calculate odds ratio (OR) and 95% confidence interval (CI). Decision tree analysis (DTA) was also performed. We included 204 patients with 258 new biologic prescriptions. FAP patients had less complex Crohn’s disease (50.7% vs. 70%, p = 0.033) than non-FAP patients. FAP records indicated fewer prior surgeries (19.6% vs. 38.4% p = 0.003). There were no statistically significant differences in remission rates, disease duration, or days between prescription and receipt of biologics. In multivariable logistic regression, adjusting for baseline demographics and disease severity variables, FAP patients were less likely to undergo surgery (OR: 0.28, 95% CI [0.08−0.91], p = 0.034). DTA suggests that imaging utilization may shed light on surgical differences. We found FAP enrollment was associated with fewer surgeries in a cohort of indigent IBD patients requiring biologics. Further studies are needed to identify interventions to address healthcare disparities in IBD.

A retrospective analysis of calcium levels in pediatric trauma patients

Traumatic injury is a major cause of morbidity and mortality in pediatric patients. Hemorrhage is a known but treatable component of these outcomes. Evidence exists that major trauma patients are at high risk for hypocalcemia but the rate of pediatric occurrence is not documented. The purpose of this study was to determine the incidence of hypocalcemia in pediatric trauma patients, as well as to investigate any correlation between hypocalcemia and the need for transfusion and operative intervention. After IRB approval a retrospective analysis was conducted of all pediatric trauma patients seen in our Adult Level One, Pediatric Level Two trauma center. Significance testing for mortality was performed using Pearson's χ² test. For the remaining numeric variables, association was determined one-way analysis of variance (when comparing all classes) or Welch's two-sample t-test (when comparing subsets based on calcium or mortality). In any event, significance was determined using α=0.05. A total of 2,928 patients were identified, 1623 were excluded, primarily due to incomplete data. Patients were predominantly male following blunt trauma. Initial calcium levels were 8.73 mg/dL, 95% CI [4-10.9] and 8.97 mg/dL, 95% CI [6.42-13.1] when correcting for albumin levels. Acute declines were noted when comparing initial and corrected serum calcium levels in patients requiring transfusion (7.99 mg/dL and 8.72 mg/dL) and operative intervention (8.54 mg/dL and 8.91 mg/dL). 456 (34.9%) patients required operative intervention, 138 (10.6%) required transfusion and 29 (2.2%) required massive transfusion. Patients in our cohort arrived with calcium values on the low end of normal, with a trend towards hypocalcemia if operative intervention or blood transfusion was required. This has been previously associated with increased mortality. Patients requiring operative intervention and transfusion are at increased risk for hypocalcemia and recognition of this potential is key for improved outcomes.

Plasma hydrogen sulfide: A biomarker of Alzheimer's disease and related dementias

While heart disease remains a common cause of mortality, cerebrovascular disease also increases with age, and has been implicated in Alzheimer's disease and related dementias (ADRD). We have described hydrogen sulfide (H₂S), a signaling molecule important in vascular homeostasis, as a biomarker of cardiovascular disease. We hypothesize that plasma H₂S and its metabolites also relate to vascular and cognitive dysfunction in ADRD. We used analytical biochemical methods to measure plasma H₂S metabolites and MRI to evaluate indicators of microvascular disease in ADRD. Levels of total H₂S and specific metabolites were increased in ADRD versus controls. Cognition and microvascular disease indices were correlated with H₂S levels. Total plasma sulfide was the strongest indicator of ADRD, and partially drove the relationship between cognitive dysfunction and white matter lesion volume, an indicator of microvascular disease. Our findings show that H₂S is dysregulated in dementia, providing a potential biomarker for diagnosis and intervention.

Incidence of Hypocalcemia and Role of Calcium Replacement in Major Trauma Patients Requiring Operative Intervention

Traumatic injury is a major cause of morbidity and mortality, and hemorrhage is a primary factor. Evidence exists that major trauma patients are at high risk of hypocalcemia. The purpose of this study was to determine the incidence and rate of calcium replacement in major trauma patients requiring operative intervention, and to investigate the impact of hypocalcemia on rate of transfusion and mortality. A retrospective analysis was conducted of all top-tier trauma activations presenting to our institution during a 12-month period. A total of 638 activations were identified; 441 were excluded, primarily because of lack of operative intervention. Patients were predominantly male following blunt trauma. The mean initial calcium level was 8.11 mg/dL and 8.64 mg/dL, correcting for albumin levels. An acute decline was noted when initial serum calcium levels and intraoperative calcium levels were compared (7.51 mg/dL). Intraoperative ionized calcium levels were on the low end of the normal range, and 28.42% received supplemental calcium. Patients in our cohort arrived hypocalcemic, which has been previously associated with increased mortality. Patients requiring operative intervention are at increased risk of hypocalcemia. Recognition of this potential is key for improved outcomes.

Neurogranin Regulates Alcohol Sensitivity through AKT Pathway in the Nucleus Accumbens

Dysfunction of glutamate neurotransmission in the nucleus accumbens (NAc) has been implicated in the pathophysiology of alcohol use disorders (AUD). Neurogranin (Ng) is exclusively expressed in the brain and mediates N-methyl-d-aspartate receptor (NMDAR) hypo-function by regulating the intracellular calcium-calmodulin (Ca²⁺ -CaM) pathway. Ng null mice (Ng^-/- mice) demonstrate increased alcohol drinking compared to wild-type mice, while also showing less tolerance to the effect of alcohol. To identify the molecular mechanism related to alcohol seeking, both in vivo microdialysis and label-free quantification proteomics comparing Ng genotype and effects of alcohol treatment on the NAc are utilized. There is significant difference in glutamate and gamma-aminobutyric acid (GABA) neurotransmission between genotypes; however, alcohol administration normalizes both glutamate and GABA levels in the NAc. Using label-free proteomics, 427 protein expression changes are identified against alcohol treatment in the NAc among 4347 total proteins detected. Bioinformatics analyses reveal significant molecular differences in Ng null mice in response to acute alcohol treatment. Ingenuity pathway analysis found that the AKT network is altered significantly between genotypes, which may increase the sensitivity of alcohol in Ng null mice. The pharmacoproteomics results presented here illustrate a possible molecular basis of the alcohol sensitivity through Ng signaling in the NAc.

What and how are EM residents being taught to respond to the next disaster?

OBJECTIVE

Disasters, both natural and man-made, have become commonplace and emergency physicians serve on the front line. Residency may be the only time that emergency physicians are exposed to a disaster, through training, until one happens in their department; therefore, it is critical to provide residents with appropriate and timely disaster education. The goal of this study was to assess the current status of disaster education in emergency medicine (EM) residencies in the United States.

METHODS

A list of disaster topics was generated by reviewing disaster literature and validated by subject matter experts. Between May and December 2016, the authors conducted a national computerized survey of the 229 US EM residencies listed by the American Osteopathic Association and the American Medical Association. It focused on the methods of instruction and amount of time devoted to each topic.

RESULTS

Of the 229 eligible residency programs, 183 (79.9 percent) completed the survey. Of those, 98.9 percent report teaching disaster management topics. Nine of 18 disaster medicine topics were taught at >60 percent of responding programs. The most common topics were emergency management principles and mass casualty triage, while the least common was hazard vulnerability analysis. The most common method of instruction was lecture (68.5 percent) and the least common methods were journal club and field exercises.

CONCLUSIONS

Broad education in disaster medicine is provided in most US EM residencies. Standardization of topics is still lacking and would be beneficial to encourage comprehensive education. Addressing the educational gaps and curriculum methodology changes identified in this survey would increase curriculum standardization.

Venous thromboembolism in IBD: Increased risk for women in CD?

Although coagulation disturbances have been described in inflammatory bowel disease (IBD), it remains unclear how common venous thromboembolism (VTE) is in IBD, and what factors influence VTE frequency. We evaluated VTE in Crohn's disease (CD) and ulcerative colitis (UC) at LSUHSC-S, a southern US medical center with an approximately equal White: African-American (AA) (1.12:1) patient base. This retrospective study evaluated VTE as a co-morbidity in IBD as a function of age, gender and race based on ICD-10 coding (2011-2015.) Results. Of 276 IBD diagnostic records, 213 were for CD (77.17%) and 63 for UC (22.8%). 52% of the CD patients were white, 42% were AA, and 6% were other. 42% of CD patients were male, with 58% were female. 6.1% (13 patients) of the 213 CD patients had a VTE. Of these 13 CD patients, 9 had active disease and 4 were in remission. 9 of 13 were female and 4 were male, with 5 white patients and 4 A A patients. 63 patients were diagnosed with UC, 3.38-fold fewer cases than CD. 25 UC patients were white, 25 were AA and 13 were in other ethnic groups. Of 63 UC cases, 2 UC patients had a VTE, both with active disease. At our institution, VTE appears to be 3x more frequently associated with CD than UC and was more common in white female patients. The recognition of VTE risk in CD, particularly in women, may be an important observation which may guide therapy and limit potentially life-threatening consequences.

Pharmacoproteomics Profile in Response to Acamprosate Treatment of an Alcoholism Animal Model

Acamprosate is an FDA-approved medication for the treatment of alcoholism that is unfortunately only effective in certain patients. Although acamprosate is known to stabilize the hyper-glutamatergic state in alcoholism, pharmacological mechanisms of action in brain tissue remains unknown. To investigate the mechanism of acamprosate efficacy, the authors employ a pharmacoproteomics approach using an animal model of alcoholism, type 1 equilibrative nucleoside transporter (ENT1) null mice. The results demonstrate that acamprosate treatment significantly decreased both ethanol drinking and preference in ENT1 null mice compared to that of wild-type mice. Then, to elucidate acamprosate efficacy mechanism in ENT1 null mice, the authors utilize label-free quantification proteomics comparing both genotype and acamprosate treatment effects in the nucleus accumbens (NAc). A total of 1040 protein expression changes are identified in the NAc among 3634 total proteins detected. The proteomics and Western blot result demonstrate that acamprosate treatment decreased EAAT expression implicating stabilization of the hyper-glutamatergic condition in ENT1 null mice. Pathway analysis suggests that acamprosate treatment in ENT1 null mice seems to rescue glutamate toxicity through restoring of RTN4 and NF-κB medicated neuroimmune signaling compared to wild-type mice. Overall, pharmacoproteomics approaches suggest that neuroimmune restoration is a potential efficacy mechanism in the acamprosate treatment of certain sub-populations of alcohol dependent subjects.

Theiler's Virus-Mediated Immunopathology in the CNS and Heart: Roles of Organ-Specific Cytokine and Lymphatic Responses

Theiler's murine encephalomyelitis virus (TMEV) induces different diseases in the central nervous system (CNS) and heart, depending on the mouse strains and time course, with cytokines playing key roles for viral clearance and immune-mediated pathology (immunopathology). In SJL/J mice, TMEV infection causes chronic TMEV-induced demyelinating disease (TMEV-IDD) in the spinal cord about 1 month post-inoculation (p.i.). Unlike other immunopathology models, both pro- and anti-inflammatory cytokines can play dual roles in TMEV-IDD. Pro-inflammatory cytokines play beneficial roles in viral clearance while they are also detrimental in immune-mediated demyelination. Anti-inflammatory cytokines suppress not only protective anti-viral immune responses but also detrimental autoreactive immune responses. Conversely, in C3H mice, TMEV infection induces a non-CNS disease, myocarditis, with three distinctive phases: phase I, viral pathology with interferon and chemokine responses; phase II, immunopathology mediated by acquired immune responses; and phase III, cardiac fibrosis. Although the exact mechanism(s) by which a single virus, TMEV, induces these different diseases in different organs is unclear, our bioinformatics approaches, especially principal component analysis (PCA) of transcriptome data, allow us to identify the key factors contributing to organ-specific immunopathology. The PCA demonstrated that in vitro infection of a cardiomyocyte cell line reproduced the transcriptome profile of phase I in TMEV-induced myocarditis; distinct interferon/chemokine-related responses were induced in vitro in TMEV-infected cardiomyocytes, but not in infected neuronal cells. In addition, the PCA of the in vivo CNS transcriptome data showed that decreased lymphatic marker expressions were weakly associated with inflammation in TMEV infection. Here, dysfunction of lymphatic vessels is shown to potentially contribute to immunopathology by delaying the clearance of cytokines and immune cells from the inflammatory site, although this can also confine the virus at these sites, preventing virus spread via lymphatic vessels. On the other hand, in the heart, dysfunction of lymphatics was associated with reduced lymphatic muscle contractility provoked by pro-inflammatory cytokines. Therefore, TMEV infection may induce different patterns of cytokine expressions as well as lymphatic vessel dysfunction by rather different mechanisms between the CNS and heart, which might explain observed patterns of organ-specific immunopathology.

Urine Drug Screen Trends from 1998 through 2011 Among Emergency Department Patients Treated in a University Teaching Hospital

The emergency department (ED) at Louisiana State University-Health Science Center in Shreveport (LSUHSC-S) serves an urban population with a large rural catchment area. This study focuses on demographic variables in substance abuse trends in this region based on urine drug screen (UDS) results. A database of de-identified UDSs ordered in the ED at LSUHSC-S between 1998 and 2011 was analyzed. Samples were tested for the presence of amphetamines, barbiturates, benzodiazepines, cannabinoids, cocaine, 3,4-methylenedioxymethamphetamine (MDMA), methadone, methamphetamine, opiates, phencyclidine, and propoxyphene. The patient population was categorized by age group, gender, and race. The majority of tests were performed on African-American and Caucasian patients ages 18 to 54 followed by the 0 to 11-year-old group. Of the drugs tested, cannabinoids represented the highest percentage of positive results in both the African-American and Caucasian populations. Opiates returned the highest percent of positive results among all prescription drugs. The Caucasian population predominated in positive tests for prescription drugs (opiates and benzodiazepines), while the African-American population predominated in results positive for illicit drugs (cannabinoids and cocaine). The increasing presence of opiates and cannabinoids, particularly in very young patients, should prompt policy makers and healthcare providers to develop intervention strategies to protect the most vulnerable populations.

Effect of sedative agent selection on morbidity, mortality and length of stay in patients with increase in intracranial pressure

BACKGROUND

To identify the effects of sedative agent selection on morbidity, mortality, and length of stay in patients with suspected increase in intracranial pressure. Recent trends and developments have resulted in changes to medications that were previously utilized as pharmacological adjuncts in the sedation and intubation of patients with suspected increases in intracranial pressure. Medications that were previously considered contraindicated are now being used with increasing regularity without demonstrated safety and effectiveness. The primary objective of this study is to evaluate and compare the use of Ketamine as an induction agent for patients with increased intracranial pressure. The secondary objective was to evaluate and compare the use of Etomidate, Midazolam, and Ketamine in patients with increased intracranial pressure.

METHODS

We conducted a retrospective chart review of patients transported to our facility with evidence of intracranial hypertension that were intubated before trauma center arrival. Patients were identified during a 22-month period from January 2014 to October 2015. Goals were to evaluate the impact of sedative agent selection on morbidity, mortality, and length of stay.

RESULTS

During the review 148 patients were identified as meeting inclusion criteria, 52 were excluded due to incomplete data. Of those the patients primarily received; Etomidate, Ketamine, and Midazolam. Patients in the Ketamine group were found to have a lower mortality rate after injury stratification.

CONCLUSION

Patients with intracranial hypertension should not be excluded from receiving Ketamine during intubation out of concern for worsening outcomes.

Blood circulating microparticle species in relapsing-remitting and secondary progressive multiple sclerosis. A case-control, cross sectional study with conventional MRI and advanced iron content imaging outcomes

BACKGROUND

Although multiple sclerosis (MS) is thought to represent an excessive and inappropriate immune response to several central nervous system (CNS) autoantigens, increasing evidence also suggests that MS may also be a neurovascular inflammatory disease, characterized by endothelial activation and shedding of cell membrane microdomains known as 'microparticles' into the circulation.

OBJECTIVE

To investigate the relationships between these endothelial biomarkers and MS.

METHODS

We examined the relative abundance of CD31(+)/PECAM-1, CD51(+)CD61(+) (αV-β3) and CD54(+) (ICAM-1) bearing microparticles in sera of healthy individuals, patients with relapsing-remitting MS, and secondary-progressive MS. We also investigated the correlation among circulating levels of different microparticle species in MS with conventional MRI (T2- and T1-lesion volumes and brain atrophy), as well as novel MR modalities [assessment of iron content on susceptibility-weighted imaging (SWI)-filtered phase].

RESULTS

Differences in circulating microparticle levels were found among MS groups, and several microparticle species (CD31(+)/CD51(+)/CD61(+)/CD54(+)) were found to correlate with conventional MRI and SWI features of MS.

CONCLUSION

These results indicate that circulating microparticles' profiles in MS may support mechanistic roles for microvascular stress and injury which is an underlying contributor not only to MS initiation and progression, but also to pro-inflammatory responses.

Gastric cancer in women: A regional health-center seven year retrospective study

AIM: To investigate whether regional geography influences ethnic and gender trends for the development of gastric cancer (GC).

METHODS: This retrospective analysis of the INVISION patient database at Louisiana State University Health Sciences Center-Shreveport (LSUHSC-S), a southern United States regional hospital, was performed from 2005-2011. Using the international statistical classification of diseases 9 (ICD-9), inpatient, day surgery outpatient, and emergency outpatient diagnosis codes entered into medical records were used to identify GC patients. For each study year, the patients were evaluated for age, ethnicity, and gender, and each patient was counted only once throughout the study. Subsequent patient encounters were counted as visits and separated by inpatient and clinic visits. Complex or severe disease may require more frequent and intensive clinical management; therefore, we evaluated annual clinic visits as “surrogate markers” of disease severity. Finally, we studied the primary diagnosis for Helicobacter pylori (H. pylori) infection (ICD-9 code 41.86) as an additional factor that might increase the risk of GC.

RESULTS: A total of 285 patients were diagnosed with GC at LSUHSC-S between 2005 and 2011. African Americans (181 patients, 89 males and 92 females, 63.5% of total patients) had significantly higher frequencies of GC diagnosis compared with non-Hispanic whites (104 patients, 54 males and 50 females, 36.5% of total patients), at a ratio of 1.74 (P = 0.002). Within each ethnic group, men and women were diagnosed at approximately equal annual rates. Our findings differed significantly from United States national trends, which found that African American females and white females had lower risks for GC than their corresponding male counterparts. The United States national trend between 2005 and 2011 showed that African Americans males had a higher incidence of GC, with an annual mean (per 100000) of 16.31 ± 0.76 compared with white males (9 ± 0.1, P < 0.001), African American females (8.7 ± 0.34, P < 0.001) and white females (4.05 ± 0.07, P < 0.001). Among the GC patients, the number of clinic visits was highest among African American males (195.1 ± 28.1), who had significantly more clinic visits than African Americans females (123 ± 13.02, P < 0.05), white males (41.57 ± 4.74, P < 0.001) and white females (35 ± 8.9, P < 0.001). Similar trends were found for inpatient visits, with an annual mean of 11.43 ± 1.5 for African American males, followed by African American females (7.29 ± 1.36), white males (2.57 ± 0.69) and white females (1.57 ± 0.612). African American males had significantly more inpatient visits than white males (P < 0.001), and African American females had more inpatient visits than white females (P < 0.01). African American patients showed the highest frequency of H. pylori positive status, with approximately 72% vs 28% for the white patients.

CONCLUSION: Increase in GC diagnoses among women at LSUHSC-S is significantly higher than United States national averages, suggesting local geographic and socioeconomic influences may alter GC disease course.

Both MC1 and MC3 Receptors Provide Protection From Cerebral Ischemia-Reperfusion-Induced Neutrophil Recruitment

OBJECTIVE

Neutrophil recruitment is a key process in the pathogenesis of stroke, and may provide a valuable therapeutic target. Targeting the melanocortin (MC) receptors has previously shown to inhibit leukocyte recruitment in peripheral inflammation, however, it is not known whether treatments are effective in the unique cerebral microvascular environment. Here, we provide novel research highlighting the effects of the MC peptides on cerebral neutrophil recruitment, demonstrating important yet discrete roles for both MC1 and MC3.

APPROACH AND RESULTS

Using intravital microscopy, in 2 distinct murine models of cerebral ischemia-reperfusion (I/R) injury, we have investigated MC control for neutrophil recruitment. After global I/R, pharmacological treatments suppressed pathological neutrophil recruitment. MC1 selective treatment rapidly inhibited neutrophil recruitment while a nonselective MC agonist provided protection even when coadministered with an MC3/4 antagonist, suggesting the importance of early MC1 signaling. However, by 2-hour reperfusion, MC1-mediated effects were reduced, and MC3 anti-inflammatory circuits predominated. Mice bearing a nonfunctional MC1 displayed a transient exacerbation of neutrophil recruitment after global I/R, which diminished by 2 hours. However importantly, enhanced inflammatory responses in both MC1 mutant and MC3 (-/-) mice resulted in increased infarct size and poor functional outcome after focal I/R. Furthermore, we used an in vitro model of leukocyte recruitment to demonstrate these anti-inflammatory actions are also effective in human cells.

CONCLUSIONS

These studies reveal for the first time MC control for neutrophil recruitment in the unique pathophysiological context of cerebral I/R, while also demonstrating the potential therapeutic value of targeting multiple MCs in developing effective therapeutics.

Bioinformatics multivariate analysis determined a set of phase-specific biomarker candidates in a novel mouse model for viral myocarditis

BACKGROUND

Myocarditis is an inflammatory disease of the cardiac muscle and is mainly caused by viral infections. Viral myocarditis has been proposed to be divided into 3 phases: the acute viral phase, the subacute immune phase, and the chronic cardiac remodeling phase. Although individualized therapy should be applied depending on the phase, no clinical or experimental studies have found biomarkers that distinguish between the 3 phases. Theiler's murine encephalomyelitis virus belongs to the genus Cardiovirus and can cause myocarditis in susceptible mouse strains.

METHODS AND RESULTS

Using this novel model for viral myocarditis induced with Theiler's murine encephalomyelitis virus, we conducted multivariate analysis including echocardiography, serum troponin and viral RNA titration, and microarray to identify the biomarker candidates that can discriminate the 3 phases. Using C3H mice infected with Theiler's murine encephalomyelitis virus on 4, 7, and 60 days post infection, we conducted bioinformatics analyses, including principal component analysis and k-means clustering of microarray data, because our traditional cardiac and serum assays, including 2-way comparison of microarray data, did not lead to the identification of a single biomarker. Principal component analysis separated heart samples clearly between the groups of 4, 7, and 60 days post infection. Representative genes contributing to the separation were as follows: 4 and 7 days post infection, innate immunity-related genes, such as Irf7 and Cxcl9; 7 and 60 days post infection, acquired immunity-related genes, such as Cd3g and H2-Aa; and cardiac remodeling-related genes, such as Mmp12 and Gpnmb.

CONCLUSIONS

Sets of molecules, not single molecules, identified by unsupervised principal component analysis, were found to be useful as phase-specific biomarkers.

Abstract 229: Determination of Phase-specific Biomarkers of Viral Myocarditis Induced by Theiler’s virus Using Multivariate Analyses of Viral Genome, Troponin, Transcriptome and Echocardiography Data

Viral myocarditis has been proposed to be initiated by viral replication in the heart (acute phase), followed by immune-mediated damage (subacute phase), where each phase requires anti-viral and immunomodulatory treatments, respectively. There are no specific biomarkers to distinguish acute from subacute phases of myocarditis while serum troponin, echocardiography, and myocardial biopsy data have been used for diagnosis clinically. To determine the phase-specific biomarkers, we used a mouse model for myocarditis induced by Theiler’s murine encephalomyelitis virus (TMEV), which belongs to the genus Cardiovirus, the family Picornaviridae. We conducted multivariate analyses of viral genome, serum cardiac troponin I, echocardiography, histology, and transcriptome using microarray data of the heart tissue harvested on 4 (acute) and 7 (subacute) days post infection (dpi). The level of viral RNA semi-quantified by RT-PCR was 10-fold higher on 4 dpi (ΔCt = 2.5×10-2 ± 4.9×10-3) than 7 dpi (ΔCt = 2.6×10-3 ± 3.0×10-4) (P < 0.05). Serum troponin was undetectable in 4 of 10 mice on 4 dpi and only in 1 of 10 mice on 7 dpi; the serum troponin levels (ng/ml) on 4 dpi (42.9 ± 15.6) were significantly lower than 7 dpi (249.9 ± 62.8) (P < 0.05). The levels of viral RNA and troponin were strongly correlated on 4 dpi (r = 0.79, P < 0.05), but not 7 dpi (P = 0.12), suggesting that viral replication could be a major cause of myocardial damage only on 4 dpi. We found multiple high intensity cardiac lesions using echocardiography with histological myocarditis on 7 dpi, but not 4 dpi. Transcriptome analyses of microarray data showed upregulation of genes associated with innate immune responses in samples from 4 and 7 dpi, compared with controls. Samples from 7 dpi showed upregulation of genes associated with T, B, and antigen presenting cells and downregulation of cardiac myosin-related genes (Myl4, Myl7, and Mybphl), compared with 4 dpi, suggesting that acquired immune responses contribute to cardiomyocyte damage on 7 dpi. In summary, the chronological order of emergence of biomarker candidates was 1) viral genome and innate immunity, 2) troponin, and 3) acquired immunity and echo and histological changes.

Identification of genes correlated with early-stage bladder cancer progression

Transitional cell carcinoma (TCC) of the bladder ranks fourth in incidence of all cancers in the developed world, yet the mechanisms of its origin and progression remain poorly understood. There are also few useful diagnostic or prognostic biomarkers for this disease. We have combined a transgenic mouse model for invasive bladder cancer (UPII-SV40Tag mice) with DNA microarray technology to determine molecular mechanisms involved in early TCC development and to identify new biomarkers for detection, diagnosis, and prognosis of TCC. We have identified genes that are differentially expressed between the bladders of UPII-SV40Tag mice and their age-matched wild-type littermates at 3, 6, 20, and 30 weeks of age. These are ages that correspond to premalignant, carcinoma in situ, and early-stage and later stage invasive TCC, respectively. Our preliminary analysis of the microarray data sets has revealed approximately 1,900 unique genes differentially expressed (> or =3-fold difference at one or more time points) between wild-type and UPII-SV40Tag urothelium during the time course of tumor development. Among these, there were a high proportion of cell cycle regulatory genes and a proliferation signaling genes that are more strongly expressed in the UPII-SV40Tag bladder urothelium. We show that several of the genes upregulated in UPII-SV40Tag urothelium, including RacGAP1, PCNA, and Hmmr, are expressed at high levels in superficial bladder TCC patient samples. These findings provide insight into the earliest events in the development of bladder TCC as well as identify several promising early-stage biomarkers.

Abstract A16: DNA microarray analysis of the UPII-SV40Tag model for invasive bladder TCC: Identification of markers for bladder premalignancy

Transitional cell carcinoma of the bladder (TCC) ranks 4th in incidence of all cancers in the developed world, yet the mechanisms of its origin and progression remain poorly understood. There are a few commercially available urine-based tests for screening and surveillance for bladder cancer, but none of these can detect premalignancy. We have combined a transgenic mouse model for invasive bladder cancer (UPII-SV40Tag mice) with DNA microarray technology, in order to determine molecular mechanisms involved in early TCC development and to identify new biomarkers for detection, diagnosis and prognosis of TCC. We have identified genes that are differentially expressed between the bladders of UPII-SV40Tag mice and their age-matched wild type (WT) littermates at 3, 6, 20 and 30 weeks of age. These are ages which correspond to premalignant, carcinoma in-situ, and early and later stage papillary TCC, respectively. There were approximately 1,900 unique genes differentially expressed (&gt;= 3-fold difference at one or more time points) between WT and UPII-SV40Tag urothelium during the time course of tumor development. Among these, there were a high proportion of cell cycle regulatory genes and proliferation signaling genes that are more strongly expressed in the UPII-SV40Tag bladder urothelium. We have tested several of the genes upregulated in UPII-SV40Tag urothelium, including autocrine motility factor (AMFR), hyaluronan-mediated motility receptor (Hmmr), proliferating cell nuclear antigen (PCNA), Rac GTPase activating protein 1 (RacGAP 1) and others as biomarkers for premalignancy, in urine samples from a recently completed Phase II, randomized, placebo controlled chemoprevention trial (N01 CN85186, PI: A. Sabichi) that was designed to test whether celecoxib can prevent recurrence in patients successfully treated by TUR for non-muscle invasive bladder cancer.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):A16.

Identification of the B-Raf/Mek/Erk MAP kinase pathway as a target for all-trans retinoic acid during skin cancer promotion

Background

Retinoids have been studied extensively for their potential as therapeutic and chemopreventive agents for a variety of cancers, including nonmelanoma skin cancer (NMSC). Despite their use for many years, the mechanism of action of retinoids in the prevention of NMSC is still unclear. In this study we have attempted to understand the chemopreventive mechanism of all-trans retinoic acid (ATRA), a primary biologically active retinoid, in order to more efficiently utilize retinoids in the clinic.

Results

We have used the 2-stage dimethylbenzanthracene (DMBA)/12-O-tetradecanoylphorbol-13-acetate (TPA) mouse skin carcinogenesis model to investigate the chemopreventive effects of ATRA. We have compared the gene expression profiles of control skin to skin subjected to the 2-stage protocol, with or without ATRA, using Affymetrix 430 2.0 DNA microarrays. Approximately 49% of the genes showing altered expression with TPA treatment are conversely affected when ATRA is co-administered. The activity of these genes, which we refer to as 'counter-regulated', may contribute to chemoprevention by ATRA. The counter-regulated genes have been clustered into functional categories and bioinformatic analysis has identified the B-Raf/Mek/Erk branch of the MAP kinase pathway as one containing several genes whose upregulation by TPA is blocked by ATRA. We also show that ATRA blocks signaling through this pathway, as revealed by immunohistochemistry and Western blotting. Finally, we found that blocking the B-Raf/Mek/Erk pathway with a pharmacological inhibitor, Sorafenib (BAY43-9006), induces squamous differentiation of existing skin SCCs formed in the 2-stage model.

Conclusion

These results indicate that ATRA targets the B-Raf/Mek/Erk signaling pathway in the 2-stage mouse skin carcinogenesis model and this activity coincides with its chemopreventive action. This demonstrates the potential for targeting the B-Raf/Mek/Erk pathway for chemoprevention and therapy of skin SCC in humans. In addition our DNA microarray results provide the first expression signature for the chemopreventive effect of ATRA in a mouse skin cancer model. This is a potential source for novel targets for ATRA and other chemopreventive and therapeutic agents that can eventually be tested in the clinic.

Global transcriptional profiling reveals Streptococcus agalactiae genes controlled by the MtaR transcription factor

Background

Streptococcus agalactiae (group B Streptococcus; GBS) is a significant bacterial pathogen of neonates and an emerging pathogen of adults. Though transcriptional regulators are abundantly encoded on the GBS genome, their role in GBS pathogenesis is poorly understood. The mtaR gene encodes a putative LysR-type transcriptional regulator that is critical for the full virulence of GBS. Previous studies have shown that an mtaR^- mutant transports methionine at reduced rates and grows poorly in normal human plasma not supplemented with methionine. The decreased virulence of the mtaR mutant was correlated with a methionine transport defect; however, no MtaR-regulated genes were identified.

Results

Microarray analysis of wild-type GBS and an mtaR mutant revealed differential expression of 12 genes, including 1 upregulated and 11 downregulated genes in the mtaR mutant. Among the downregulated genes, we identified a cluster of cotranscribed genes encoding a putative methionine transporter (metQ1NP) and peptidase (pdsM). The expression of four genes potentially involved in arginine transport (artPQ) and arginine biosynthesis (argGH) was downregulated and these genes localized to two transcriptional units. The virulence factor cspA, which encodes an extracellular protease, was downregulated. Additionally, the SAN_1255 locus, which putatively encodes a protein displaying similarity to plasminogen activators, was downregulated.

Conclusion

To our knowledge, this is the first study to describe the global influence of MtaR on GBS gene expression. This study implicates the metQ1NP genes as encoding the MtaR-regulated methionine transporter, which may provide a mechanistic explanation for the methionine-dependent growth defect of the mtaR mutant. In addition to modulating the expression of genes involved in metabolism and amino acid transport, inactivation of mtaR affected the expression of other GBS genes implicated in pathogenesis. These findings suggest the possibility that MtaR may play a multifaceted role in GBS pathogenesis by regulating the expression of numerous genes.

Abstract B52: Identification of genes involved in early stage bladder cancer progression

B52

Transitional cell carcinoma of the bladder (TCC) ranks 4th in incidence of all cancers in the developed world, yet the mechanisms of its origin and progression remain poorly understood. There are also few useful diagnostic or prognostic biomarkers for this disease. We have combined a transgenic mouse model for invasive bladder cancer (UPII-SV40T mice) with DNA microarray technology, in order to determine molecular mechanisms involved in early TCC development and to identify new biomarkers for detection, diagnosis and prognosis of TCC. We have identified genes that are differentially expressed between the bladders of UPII-SV40T mice and their age-matched wild type (WT) littermates at 3, 6, 20 and 30 weeks of age. These are times which correspond to premalignant, carcinoma in-situ, and early and later stage papillary TCC, respectively. There were approximately 1,900 unique genes differentially expressed (≥ 3-fold difference at one or more time points) between WT and UPII-SV40T urothelium during the time course of tumor development. Among these, there were a high proportion of cell cycle regulatory genes and cytokinesis genes that are more strongly expressed in the UPII-SV40T bladder urothelium. We have tested several of the genes upregulated in UPII-SV40T urothelium, including autocrine motility factor (AMFR), Caspase 3, Cox-2, PCNA and others as biomarkers for premalignancy in urine samples from a completed chemoprevention trial. These results will be discussed in the context of the UPII-SV40T model.

Citation Information: Cancer Prev Res 2008;1(7 Suppl):B52.

Retinoids and skin: microarrays shed new light on chemopreventive action of all-trans retinoic acid

Despite the use of retinoids in the clinic for many years, their mode of action in the prevention of skin cancer is still unclear. Recent microarray analyses of the chemopreventive effect of all-trans retinoic acid (ATRA), one of the primary naturally occurring biologically active retinoids, in the two-stage mouse skin chemical carcinogenesis model have provided novel insight into their action. Comparison of the gene expression profiles of control skin to skin subjected to the two-stage protocol for 3 wk, with or without ATRA, has shown that approximately half of the genes regulated by 12-o-tetradecanoylphorbol-13-acetate (TPA) are oppositely regulated when ATRA is coadministered with TPA. It was further shown the Raf/Mek/Erk branch of mitogen-activated protein (MAP) kinase pathway contains a disproportionate number of oppositely regulated genes, thereby implicating it as one of the key pathways involved in tumor promotion by TPA, that is blocked by ATRA. This result has pointed the way toward the detailed study of Raf/Mek/Erk pathway signaling in skin cancer development and its potential as a target pathway for chemoprevention by ATRA and other chemopreventive drugs.

Translation initiation factor eIF4G-1 binds to eIF3 through the eIF3e subunit

eIF3 in mammals is the largest translation initiation factor ( approximately 800 kDa) and is composed of 13 nonidentical subunits designated eIF3a-m. The role of mammalian eIF3 in assembly of the 48 S complex occurs through high affinity binding to eIF4G. Interactions of eIF4G with eIF4E, eIF4A, eIF3, poly(A)-binding protein, and Mnk1/2 have been mapped to discrete domains on eIF4G, and conversely, the eIF4G-binding sites on all but one of these ligands have been determined. The only eIF4G ligand for which this has not been determined is eIF3. In this study, we have sought to identify the mammalian eIF3 subunit(s) that directly interact(s) with eIF4G. Established procedures for detecting protein-protein interactions gave ambiguous results. However, binding of partially proteolyzed HeLa eIF3 to the eIF3-binding domain of human eIF4G-1, followed by high throughput analysis of mass spectrometric data with a novel peptide matching algorithm, identified a single subunit, eIF3e (p48/Int-6). In addition, recombinant FLAG-eIF3e specifically competed with HeLa eIF3 for binding to eIF4G in vitro. Adding FLAG-eIF3e to a cell-free translation system (i) inhibited protein synthesis, (ii) caused a shift of mRNA from heavy to light polysomes, (iii) inhibited cap-dependent translation more severely than translation dependent on the HCV or CSFV internal ribosome entry sites, which do not require eIF4G, and (iv) caused a dramatic loss of eIF4G and eIF2alpha from complexes sedimenting at approximately 40 S. These data suggest a specific, direct, and functional interaction of eIF3e with eIF4G during the process of cap-dependent translation initiation, although they do not rule out participation of other eIF3 subunits.

Application of machine learning and visualization of heterogeneous datasets to uncover relationships between translation and developmental stage expression of C. elegans mRNAs

The relationships between genes in neighboring clusters in a self-organizing map (SOM) and properties attributed to them are sometimes difficult to discern, especially when heterogeneous datasets are used. We report a novel approach to identify correlations between heterogeneous datasets. One dataset, derived from microarray analysis of polysomal distribution, contained changes in the translational efficiency of Caenorhabditis elegans mRNAs resulting from loss of specific eIF4E isoform. The other dataset contained expression patterns of mRNAs across all developmental stages. Two algorithms were applied to these datasets: a classical scatter plot and an SOM. The outputs were linked using a two-dimensional color scale. This revealed that an mRNA's eIF4E-dependent translational efficiency is strongly dependent on its expression during development. This correlation was not detectable with a traditional one-dimensional color scale.