Jejunoileal mucosal growth in mice with a limited microbiome

Previous work demonstrated enhanced enterocyte proliferation and mucosal growth in gnotobiotic mice, suggesting that intestinal flora participate in mucosal homeostasis. Furthermore, broad-spectrum enteral antibiotics are known to induce near germ-free (GF) conditions in mice with conventional flora (CONV). We hypothesized that inducing near GF conditions with broad-spectrum enteral antibiotics would cause ordered small intestinal mucosal growth in CONV mice but would have no effect in GF mice with no inherent microbiome. C57BL/6J CONV and GF mice received either an antibiotic solution (Ampicillin, Ciprofloxacin, Metronidazole, Vancomycin, Meropenem) or a vehicle alone. After treatment, small intestinal villus height (VH), crypt depth (CD), mucosal surface area (MSA), crypt proliferation index (CPI), apoptosis, and villus and crypt cell types were assessed. Antibiotic-treated CONV (Abx-CONV) mice had taller villi, deeper crypts, increased CPI, increased apoptosis, and greater MSA compared to vehicle-treated CONV mice. Minor differences were noted in enterocyte and enterochromaffin cell proportions between groups, but goblet and Paneth cell proportions were unchanged in Abx-CONV mice compared to vehicle-treated CONV mice (p>0.05). Antibiotics caused no significant changes in VH or MSA in GF mice when compared to vehicle-treated GF mice (p>0.05). Enteral administration of broad-spectrum antibiotics to mice with a conventional microbiome stimulates ordered small intestinal mucosal growth. Mucosal growth was not seen in germ-free mice treated with antibiotics, implying that intestinal mucosal growth is associated with change in the microbiome in this model.

Symptomatic use of carbidopa in autonomic disorders

Carbidopa is being explored as a novel therapy for hyperadrenergic symptoms of autonomic disorders, due to its potential to decrease peripheral catecholamine levels. This study retrospectively characterized patients in our autonomic clinic who were prescribed carbidopa for open label treatment of autonomic symptoms. 23 patients were included; approximately half had postural orthostatic tachycardia syndrome. Those with documented plasma catecholamines had elevated standing norepinephrine. Patients typically had multiple comorbidities and multiple failed therapies. 19 took carbidopa (typically 25 mg three times daily); 12 continued it for longer than 3 months. 11 patients reported better symptom control with carbidopa, most commonly tremor and gastrointestinal dysfunction. 4 patients reported side effects. In this small retrospective study, carbidopa was well tolerated in patients with dysautonomia, and half reported symptomatic benefit. Larger, placebo-controlled trials are warranted for further investigation of this therapy.

Preoperative MRI Evaluation of Thyroid Cartilage Invasion in Patients with Laryngohypopharyngeal Cancer: Comparison of Contrast-Enhanced 2D Spin-Echo and 3D T1-Weighted Radial Gradient Recalled-Echo Techniques

BACKGROUND AND PURPOSE

Accurate assessment of thyroid cartilage invasion on preoperative imaging influences management in patients with laryngeal and hypopharyngeal cancers. We evaluated the clinical usefulness of contrast-enhanced 3D T1-weighted radial gradient recalled-echo for preoperative assessment of thyroid cartilage invasion in patients with laryngohypopharyngeal squamous cell carcinoma, compared with 2D spin-echo T1WI.

MATERIALS AND METHODS

Preoperative MR images of 52 consecutive patients who were diagnosed with laryngeal or hypopharyngeal cancer and underwent partial or total laryngectomy were analyzed. Pathologic specimens served as reference standards. Two independent head and neck radiologists evaluated the presence of thyroid cartilage invasion in both contrast-enhanced 2D spin-echo T1WI and 3D gradient recalled-echo sequences. The sensitivity, specificity, and accuracy of the 2 modalities were compared. The area under the curve was a measure of diagnostic performance.

RESULTS

Pathologic neoplastic thyroid cartilage invasion was identified in 24 (46.2%) of the 52 patients. The sensitivity (75.0%), specificity (96.4%), and accuracy (86.5%) of contrast-enhanced 3D gradient recalled-echo were significantly higher than those of 2D spin-echo T1WI (58.3%, 89.3%, and 75.0%; P = .017, .003, and .002, respectively). 3D gradient recalled-echo had significantly better diagnostic performance (area under the curve = 0.963) than 2D spin-echo T1WI (area under the curve = 0.862; P = .010).

CONCLUSIONS

Contrast-enhanced 3D gradient recalled-echo was diagnostically superior in identifying neoplastic thyroid cartilage invasion compared with 2D spin-echo T1WI in patients with laryngohypopharyngeal cancer, and therefore, may provide more accurate preoperative staging.

Serotonin as a Mitogen in the Gastrointestinal Tract: Revisiting a Familiar Molecule in a New Role

Serotonin signaling is ubiquitous in the gastrointestinal (GI) system, where it acts as a neurotransmitter in the enteric nervous system (ENS) and influences intestinal motility and inflammation. Since its discovery, serotonin has been linked to cellular proliferation in several types of tissues, including vascular smooth muscle, neurons, and hepatocytes. Activation of serotonin receptors on distinct cell types has been shown to induce well-known intracellular proliferation pathways. In the GI tract, potentiation of serotonin signaling results in enhanced intestinal epithelial proliferation, and decreased injury from intestinal inflammation. Furthermore, activation of the type 4 serotonin receptor on enteric neurons leads to neurogenesis and neuroprotection in the setting of intestinal injury. It is not surprising that the mitogenic properties of serotonin are pronounced within the GI tract, where enterochromaffin cells in the intestinal epithelium produce 90% of the body's serotonin; however, these proliferative effects are attributed to increased serotonin signaling within the ENS compartment as opposed to the intestinal mucosa, which are functionally and chemically separate by virtue of the distinct tryptophan hydroxylase enzyme isoforms involved in serotonin synthesis. The exact mechanism by which serotonergic neurons in the ENS lead to intestinal proliferation are not known, but the activation of muscarinic receptors on intestinal crypt cells indicate that cholinergic signaling is essential to this signaling pathway. Further understanding of serotonin's role in mucosal and enteric nervous system mitogenesis may aid in harnessing serotonin signaling for therapeutic benefit in many GI diseases, including inflammatory bowel disease, malabsorptive conditions, and cancer.

MRI Features May Predict Molecular Features of Glioblastoma in Isocitrate Dehydrogenase Wild-Type Lower-Grade Gliomas

BACKGROUND AND PURPOSE

Isocitrate dehydrogenase (IDH) wild-type lower-grade gliomas (histologic grades II and III) with epidermal growth factor receptor (EGFR) amplification or telomerase reverse transcriptase (TERT) promoter mutation are reported to behave similar to glioblastoma. We aimed to evaluate whether MR imaging features could identify a subset of IDH wild-type lower-grade gliomas that carry molecular features of glioblastoma.

MATERIALS AND METHODS

In this multi-institutional retrospective study, pathologically confirmed IDH wild-type lower-grade gliomas from 2 tertiary institutions and The Cancer Genome Atlas constituted the training set (institution 1 and The Cancer Genome Atlas, 64 patients) and the independent test set (institution 2, 57 patients). Preoperative MRIs were analyzed using the Visually AcceSAble Rembrandt Images and radiomics. The molecular glioblastoma status was determined on the basis of the presence of EGFR amplification and TERT promoter mutation. Molecular glioblastoma was present in 73.4% and 56.1% in the training and test sets, respectively. Models using clinical, Visually AcceSAble Rembrandt Images, and radiomic features were built to predict the molecular glioblastoma status in the training set; then they were validated in the test set.

RESULTS

In the test set, a model using both Visually AcceSAble Rembrandt Images and radiomic features showed superior predictive performance (area under the curve = 0.854) than that with only clinical features or Visually AcceSAble Rembrandt Images (areas under the curve = 0.514 and 0.648, respectively; P < . 001, both). When both Visually AcceSAble Rembrandt Images and radiomics were added to clinical features, the predictive performance significantly increased (areas under the curve = 0.514 versus 0.863, P < .001).

CONCLUSIONS

MR imaging features integrated with machine learning classifiers may predict a subset of IDH wild-type lower-grade gliomas that carry molecular features of glioblastoma.

Reducing Underdiagnosis of Hirschsprung-Associated Enterocolitis: A Novel Scoring System

BACKGROUND

Hirschsprung-Associated Enterocolitis (HAEC) is a life-threatening and difficult to diagnose complication of Hirschsprung Disease (HSCR). The goal of this study was to evaluate existing HAEC scoring systems and develop a new scoring system.

METHODS

Retrospective, multi-institutional data collection was performed. For each patient, all encounters were analyzed. Data included demographics, symptomatology, laboratory and radiographic findings, and treatments received. A "true" diagnosis of HAEC was defined as receipt of treatment with rectal irrigations, antibiotics, and bowel rest. The Pastor and Frykman scoring systems were evaluated for sensitivity/specificity and univariate and multivariate logistic regression performed to create a new scoring system.

RESULTS

Four centers worldwide provided data on 200 patients with 1450 encounters and 369 HAEC episodes. Fifty-seven percent of patients experienced one or more episodes of HAEC. Long-segment colonic disease was associated with a higher risk of HAEC on univariate analysis (OR 1.92, 95% CI 1.43-2.57). Six variables were significantly associated with HAEC on multivariate analysis. Using published diagnostic cutoffs, sensitivity/specificity for existing systems were found to be 38.2%/96% for Pastor's and 56.4%/86.9% for Frykman's score. A new scoring system with a sensitivity/specificity of 67.8%/87.9% was created by stepwise multivariate analysis. The new score outperformed the existing scores by decreasing underdiagnosis in this patient cohort.

CONCLUSIONS

Existing scoring systems perform poorly in identifying episodes of HAEC, resulting in significant underdiagnosis. The proposed scoring system may be better at identifying those underdiagnosed in the clinical setting. Head-to-head comparison of HAEC scoring systems using prospective data collection may be beneficial to achieve standardization in the field.

Mucosal characteristics vary across developmental stages in the small intestine of C57BL/6J mice

AIMS

The benefits of utilizing laboratory mice include low cost, ease of maintenance, and accessibility of molecular tools. However, the ages of experimental mice in the literature vary drastically. We hypothesized that there exists age-related variation in the murine small intestine across developmental stages.

MATERIALS AND METHODS

Segments of small intestine were harvested from C57BL/6J mice of varying ages (E17 to 24 weeks; n = 3-4/group). Slides were analyzed for morphometric parameters, cell types, and crypt proliferation index (CPI). Secondary analysis comparing age-matched males and females (n = 4/group) was performed. Means were compared with Student's t-test and variance of proportions with the Chi-squared test to a significance of p < 0.05.

KEY FINDINGS

There were small but significant differences including regional variation in villus height, which abolished when examining the small intestine as a whole. Sexually immature mice had increased CPI compared to mature animals. The most dramatic differences were seen in mice at weaning, which demonstrated shallower crypts, increased CPI, fewer Paneth and goblet cells, and more enterochromaffin cells. Examination of embryonic intestine revealed an underdeveloped mucosa lacking differentiated cells. There were minimal differences when comparing age-matched males and females.

SIGNIFICANCE

Small, but statistically significant differences in villus height, crypt depth, and crypt proliferation are present in mice across early developmental stages. Mice at weaning exhibit variation in crypt-villus cell composition compared to older animals, which may explain the propensity for certain intestinal conditions in the very young. Investigators studying the GI mucosa should employ consistent age-matching in order to allow direct comparison between studies.

National Survey of Pediatric Intestinal Rehabilitation Programs in the United States

BACKGROUND

Pediatric intestinal rehabilitation (PIR) programs are associated with improved outcomes in children with intestinal failure but remain heterogeneous nationally. This study characterizes PIR program components to aid those seeking to establish or expand a program.

METHODS

Members of the Children's Hospital Association reporting a PIR program to the US News and World Report completed a 14-item questionnaire using the Qualtrics Online Survey Software. Programs were categorized as small or large (≤50 vs >50 patients) and new or established (≤10 vs >10 years).

RESULTS

Seventy-one programs were identified and 61 surveys were returned for a response rate of 86%. Majority of programs had gastroenterology, surgery, nutrition, nursing, and social work services involved. Large programs (n = 34; 59%) were more likely to serve as referral centers; have greater participation by nursing, social work, and primary care; have more dedicated time by gastroenterology, surgery, nursing, nutrition, and social work; have more frequent meetings; and have various funding sources (P < .05).

CONCLUSION

Critical components of a PIR program include gastroenterology, surgery, and nutrition services with strong nursing and social work support. These data document the components of modern PIR programs, though further studies on the relationship between program structure and patient outcomes are warranted.

0528 Insomnia as a Mechanism for Improvement in Alcohol Problems Among Young Adults

Introduction

More than half of heavy-drinking young adults report symptoms of insomnia, which have been associated with alcohol-related problems. This study examined improvement in insomnia (via Cognitive Behavioral Therapy for Insomnia; CBT-I) as a mechanism for improvement in alcohol-related problems.

Methods

Fifty-six heavy-drinking young adults with insomnia (ages 18-30y) were randomized to CBT-I (n=28) or single-session sleep hygiene control (SH; n=28). Of those, 43 (77%) completed post-treatment (24 SH, 19 CBT-I) and 48 (86%) completed 1-month follow-up (25 SH, 23 CBT-I). Multiple imputation was used to estimate missing data. Treatment outcomes were assessed using multilevel models. Mediation was tested using bootstrapped confidence intervals for indirect effects in the PROCESS macro.

Results

CBT-I participants reported greater decreases in insomnia severity than those in the sleep hygiene group [group X time interaction, F(2,59)=11.29, p&lt;.001], both post-treatment and at 1-month follow-up. Both groups decreased significantly in diary-assessed sleep quality [time, F(2,55)=40.30, p&lt;.001], with a marginally significant interaction in favor of the CBT-I group [F(2,55)=2.69, p=.08]. There were no significant group by time interactions in the prediction of actigraphy-assessed sleep variables, although again, there was a marginally significant interaction in the prediction of actigraphy-assessed sleep efficiency [F(2,66)=2.75, p=.07]. Both groups reported significant decreases in drinking quantity over time [time, F(2,58=13.88, p&lt;.001]. However, CBT-I participants reported greater decreases in alcohol-related consequences than those in the sleep hygiene group [F(2,67)=4.13, p=.02]. In the mediation model, CBT-I did not have a direct effect on change in alcohol-related consequences (B=1.49, SE=1.06, 95%CI=-0.65, 3.62); however, it influenced change in 1-month alcohol-related consequences indirectly through its influence on post-treatment insomnia symptoms (B=-1.09, SE=0.57, 95%CI=-2.30, -0.05).

Conclusion

CBT-I is effective in treating insomnia among heavy-drinking young adults and may be associated with reductions in alcohol-related problems due to its impact on insomnia symptoms.

Support

This work was supported by funding from the University of Missouri System Research Board Office (PI Miller). Mary Beth Miller’s contribution to this project was also supported by the National Institute on Alcohol Abuse and Alcoholism [grant number K23AA026895].

P774 Utility of global longitudinal strain to predict post-operative outcomes in non-cardiac surgery

Purpose

The aim of this study is to determine the value of GLS in predicting post-operative outcomes in patients undergoing non-cardiac surgeries.

Methods

This was a retrospective study of all patients who had echocardiography performed for a pre-operative indication from February 2017 to October 2017. These patients were screened for those who had normal LVEF, had undergone subsequent non-cardiac surgery, and had post-operative troponins measured. Medical records were traced for baseline demographics, past medical history and echocardiographic features. GLS evaluation was prospectively performed using TOMTEC-ARENA (TOMTEC Imaging Systems GmbH) by assessors blinded to patient outcomes. Outcomes for major adverse cardiovascular events and mortality up to 1 year post surgery were collected. Post-op myocardial injury was defined as a peak Troponin T value of &gt;30 ng/L or a &gt;20% increment from baseline.

Results

A total of 42 patients were included. 61.9% (n = 26) were male and mean age was 72.3 years. Only 75.6% of patients were fully independent with activities of daily living and mean creatinine was 153.4μmol/L. Mortality at 1 year was 16.7% (n = 7) and 28.6% (n = 12) were deemed to have post-operative myocardial injury. 1-year mortality was associated with a lower GLS (-23.8% vs -19.2%, p = 0.001). However, GLS was not correlated with post-operative myocardial injury or hospital readmissions. In our study population, only a history of past myocardial infarction predicted post-op myocardial injury (58.3% vs 16.7%, p = 0.019).

Conclusion

Our study did not demonstrate the utility of GLS in predicting post-operative events, but this is likely because of the small sample size with low event rates. Nevertheless, GLS values did correlate with 1-year mortality and could be a marker of frailty and an increased mortality risk.

Outcomes of neonates with listeriosis supported with extracorporeal membrane oxygenation from 1991 to 2017

BACKGROUND

Listeriosis may cause severe disease in fetuses and neonates. The outcomes of critically ill neonates with early-onset listeriosis requiring extracorporeal membrane oxygenation (ECMO) from 1975 to 1991 have been reported.

OBJECTIVE

To update the characteristics and outcomes of neonates with listeriosis supported by ECMO.

STUDY DESIGN

Retrospective study of neonates with culture-proven listeriosis reported to the Extracorporeal Life Support Organization Registry between 1991 and 2017. Comparisons were made between this cohort and the case series from 1975-1991.

RESULTS

Twenty-two neonates had culture-proven Listeria monocytogenes infection and required ECMO support. Eight-six percent survived to discharge, compared with 67% in the previous cohort (p = 0.2). The median ECMO duration was 131 h, compared with 209 h in the previous cohort (p = 0.1). Nonsurvivors had a significantly lower pre-ECMO pH (6.91 vs 7.31, p = 0.0006).

CONCLUSION

The survival of neonates with listeriosis supported with ECMO is high, supporting the use of ECMO as rescue therapy for this condition.

Trends in Routine and Complex Hepatobiliary Surgery Among General and Pediatric Surgical Residents: What is the Next Generation Learning and is it Enough?

OBJECTIVE

Previous studies reveal a correlation between surgical volume and outcomes; thus, a similar relationship likely exists between trainee operative volume and technical competence. While routine hepatobiliary surgery is commonplace, trainee exposure to the more advanced procedures may be lacking. We hypothesize that experience in complex hepatobiliary procedures may be deficient both during general surgery residency and pediatric surgery fellowship training.

DESIGN

Case log data from the ACGME were queried for general surgery residents (2000-2017) and pediatric surgery fellows (2004-2017). Laparoscopic cholecystectomy was considered a routine hepatobiliary procedure for both specialties. For general surgery, hepatic lobectomy/segmentectomy and choledochoenteric anastomosis were considered complex and for pediatric surgery, hepatic lobectomy, biliary atresia and choledochal cyst procedures were considered complex.

SETTING

Publicly available case log data from the ACGME.

PARTICIPANTS

General surgery residents and pediatric surgery fellows at ACGME-accredited training programs.

RESULTS

The number of trainees increased over the study period for both groups. Mean case volumes for laparoscopic cholecystectomy increased by 36% in surgery graduates and by 114% in pediatric surgery graduates. In surgery, the mean volumes for choledochoenteric anastomosis procedures decreased by 53% from 3.0 to 1.4 procedures/year with increasing variability in trainee experience. Volumes for hepatic lobectomy/segmentectomy increased by 68% from 3.4 to 5.7 procedures/year with decreasing variability. In pediatric surgery, case volumes for complex procedures were low (mean <4/year), highly variable among trainees, and appear unchanged between 2004 and 2017. In every year analyzed, at least 1 pediatric surgery trainee reported doing 0 cases in one of these complex categories.

CONCLUSIONS

Case logs suggest that the volume of complex hepatobiliary surgery remains low and highly variable in both disciplines with some trainees obtaining minimal or no exposure to certain cases. The relationship between these trends and the development of competency is worthy of further study.

Potentiation of serotonin signaling leads to increased carbohydrate and lipid absorption in the murine small intestine

BACKGROUND

Enteric serotonin influences intestinal homeostasis and functions as a mucosal growth factor. Previously, we demonstrated increased mucosal surface area and enhanced crypt cell proliferation in serotonin reuptake transporter (SERT)-deficient mice. Therefore, we hypothesized that serotonin-mediated mucosal growth would also result in enhanced carbohydrate and lipid absorption.

MATERIAL AND METHODS

Wild-type C57Bl/6 (WT) and SERT-knockout (SERTKO) mice were fasted then gavaged with D-xylose or boron-dipyrromethene (BODIPY) FL-C12 medium-chain fatty acid analog. Serum D-xylose and BODIPY concentrations were serially measured from blood drawn at 30 to 360 min post-gavage. Small intestine was harvested from both groups for comparison of morphometric parameters. Area under the curve of plotted graphs was calculated, and means were compared with Student's t-test to a significance of p < 0.05.

RESULTS

Villus height and crypt depth were significantly greater in the middle and distal small intestine of SERTKO animals compared to WT. Overall absorption of D-xylose and BODIPY was greater in SERTKO animals compared to WT animals. Absorption of D-xylose was persistently elevated in SERTKO animals, while there was an initial delay in BODIPY absorption followed by a sustained and significantly greater absorption in SERTKO animals at 60-360 min after gavage.

CONCLUSION

Potentiation of serotonin signaling in SERTKO mice results in small intestinal mucosal growth and enhanced carbohydrate and fat absorption in vivo. These functional increases support the concept of targeting the serotonin signaling system to augment intestinal adaptation in the setting of intestinal failure.

The 5-HT4 Receptor Agonist Prucalopride Stimulates Mucosal Growth and Enhances Carbohydrate Absorption in the Ileum of the Mouse

BACKGROUND

Enteric serotonin may function as a mucosal growth factor. Previous work demonstrated increased crypt cell proliferation and intestinal mucosal surface area with potentiation of serotonin. While an indirect mechanism was postulated to explain these effects, the presence of 5-HT4 receptors on enterocytes raises the possibility of a direct action of serotonin. We hypothesized that a 5-HT4 specific agonist, prucalopride, would stimulate intestinal mucosal growth and enhance absorptive function in the murine small intestine.

METHODS

Adult wild-type mice were treated parenterally with prucalopride for 14 days via surgically implanted osmotic pumps. In vivo D-xylose absorption was assessed by oral gavage and serum D-xylose measurements. On day 14, glucose absorption was assessed by instilling a glucose solution into isolated segments of small intestine. The bowel was harvested and examined for morphologic parameters and crypt cell proliferation.

RESULTS

Villus height, crypt depth, and crypt proliferation were significantly increased in the distal small bowel of prucalopride-treated mice compared with control animals. Crypt depth was also increased in the proximal and middle small intestine in treated mice. There was no difference in D-xylose absorption throughout the study period; however, glucose absorption was significantly increased in the distal small intestine of prucalopride-treated mice.

CONCLUSION

Parenteral administration of the 5-HT4 receptor specific agonist, prucalopride, results in morphologic and functional changes in the murine small intestine that are most prominent in the distal small bowel. While further studies are necessary to delineate the mechanism, it is plausible that the effects are mediated by 5-HT4 receptors on enterocytes.

Serum Citrulline Levels Exhibit Circadian Variation and Fluctuations in Relation to Food Intake in Mice

Background

Plasma citrulline is a nonessential amino acid synthesized almost exclusively by enterocytes of the small intestine. Correlation between post-operative plasma citrulline levels and remnant small bowel mass and function has led to its use as a simple biomarker of functional intestinal mass in adults and children, with a proposed prognostic value for achieving enteral autonomy in the setting of intestinal failure. While it is standard to measure fasting levels in humans, the optimal timing of blood draws in relation to food intake and time of day has not been standardized and is poorly studied in animal models. We hypothesize that serum citrulline levels vary both throughout the day and with relation to food intake in mice.

Methods

Serum citrulline levels were measured from 12 C57BL/6 mice (6 - 9 weeks old) in the mornings and evenings, either after ad libitum food intake or after 8 - 12 h of access to water only. Blood draws for each experimental set-up were performed 1 week apart according to our Institutional Animal Care and Use Committee (IACUC) guidelines for acceptable blood collection volumes for survival procedures. At the end of the experiment, mice were euthanized and small intestine was harvested for morphometric measurements. Group means were compared using Student’s t-test with significance assumed for P < 0.05.

Results

After withholding chow for 8 - 12 h, serum citrulline levels were significantly greater in the morning compared to levels drawn in the evening. When mice were allowed ad libitum chow, there was no significant difference in serum citrulline levels drawn in the morning compared to the evening. There was no difference detected in villus height across the different experimental conditions.

Conclusions

Serum citrulline levels exhibit circadian variation and fluctuations in relation to food intake in mice, without apparent concurrent changes in enterocyte mass. There was no diurnal variation of serum citrulline levels in fed mice whereas fasted mice had significantly higher levels of serum citrulline in the morning compared to the evening. These findings underscore the paramount importance of consistent sample collection strategies in the setting of translational research.

The Limited Utility of Routine Culture in Pediatric Pilonidal, Gluteal, and Perianal Abscesses

BACKGROUND

Pilonidal, buttock, and perianal abscesses are common reasons for surgical consultation in the pediatric emergency department. Treatment typically includes a bedside incision and drainage, often followed by an abscess culture, and a course of oral antibiotics. We aimed to study the impact of culture data on changes in management and clinical outcomes. We hypothesized that management is unaffected by culture data, and therefore, fluid culture from pilonidal, buttock, and perianal abscesses in the pediatric population may represent an unnecessary laboratory test and cost.

MATERIALS AND METHODS

A single institution's electronic medical record was searched between February 1, 2013 and August 1, 2017, identifying 249 pediatric patients meeting the inclusion criteria: age 0 to 18 y; diagnosis of pilonidal, buttock, or perianal abscess; bedside incision and drainage. Patients were divided into two different comparison groups for data analysis based on the presence or absence of culture and recurrence or no recurrence.

RESULTS

Culture results directly altered management in only 5 patient encounters (2.7% of all cultured). When comparing groups by culture or no culture, no statistically significant difference in recurrence rate (P = 0.4) was noted. When comparing groups by recurrence versus no recurrence, we found no statistically significant difference between sex, resident type, vessel loop use, packing use, or antibiotic use (P > 0.05).

CONCLUSIONS

We conclude that microbiological culture results are of limited utility in the management of pediatric pilonidal, buttock, and perianal abscesses as they do not appear to alter treatment, and omission of culture is not associated with failure of surgical management.

The Impact of Pediatric Surgical Specialty Meetings: A 5-year Analysis of Presented Abstracts

BACKGROUND

Abstracts presented at the American Academy of Pediatrics Section on Surgery (AAP) and American Pediatric Surgical Association (APSA) meetings can be taken as a reasonable representation of academic activity in pediatric surgery. We sought to assess ongoing trends in pediatric surgical research by analyzing the scientific content of each association's yearly meeting.

METHODS

Abstracts presented at AAP and APSA between 2009 and 2013 were identified from the final printed programs (n = 910). Video abstracts (n = 34) were excluded. Collected data included title, authors, classification (basic science/clinical), presentation type (podium/poster), and topic. Publication as a journal article was determined using the abstract title/authors in a PubMed search. Journal impact factors were recorded for each journal and a composite impact factor (CIF) was calculated by dividing the sum of impact factors by the published articles per meeting.

RESULTS

Number of abstracts presented, percentage published, abstract classifications, and presentation type remained consistent over the study period. The AAP meetings accepted a higher percentage of clinical abstracts: AAP 72.3 ± 3.4% versus APSA 65.9 ± 1.3%. The five most popular topics at both meetings were oncology, congenital diaphragmatic hernia, necrotizing enterocolitis, trauma, and appendicitis. The publication rate for clinical and basic science abstracts did not vary significantly over the study period, whereas CIFs were higher for basic science publications nearly every year. The percentage of podium abstracts published was significantly greater than poster abstracts, but no statistical difference in CIF was seen between podium- and poster-associated publications.

CONCLUSIONS

Abstracts accepted and presented at the two major pediatric surgical specialty meetings more commonly involve clinical studies with a trend away from basic science. Despite this, basic science abstracts tended to be published in higher impact journals. This study attempts to quantify the quality of pediatric surgical research and serves as a baseline for future comparison.

The relationship between clinical characteristics including presence of exposed lesions and health-related quality of life (HRQoL) in patients with psoriasis: analysis from the nationwide epidemiologic study for psoriasis in Korea (EPI-PSODE study)

BACKGROUND

Psychological aspect and quality of life should be considered in treating patients with psoriasis.

OBJECTIVE

We sought to ascertain which clinical characteristics including presence of exposed lesions are associated with impairment of health-related quality of life (HRQoL) in patients with psoriasis.

METHODS

The EPI-PSODE study was a nationwide, multicenter, cross-sectional study conducted in Korea that included 1260 adult patients with psoriasis. In addition to clinical characteristics including presence of exposed lesions, data were collected using the Psoriatic Arthritis (PsA) Screening and Evaluation (PASE), Dermatology Life Quality Index (DLQI), MOS 36-Item Short-Form Health Survey (SF-36), Work Productivity and Activity Impairment Questionnaire Psoriasis (WPAI: PSO) and Medication Satisfaction Questionnaire (MSQ).

RESULTS

Patients with a DLQI score > 5 (n = 990) were younger, had an earlier onset of psoriasis, scored higher on the Psoriasis Area and Severity Index (PASI), had higher body surface area (BSA) and had higher PASE scores than patients with DLQI ≤ 5 (n = 266). The group of patients with exposed lesions (n = 871) were younger and male predominance, earlier onset of psoriasis, longer disease duration, higher PASI/BSA score and a higher proportion with drinking and smoking history each than the group of patients without exposed lesions (n = 389). Presence of exposed lesions negatively influenced DLQI, 36-Item Short-Form Health Survey (SF-36) (mental component), presenteeism, total work productivity impairment and total activity impairment in the WPAI: PSO. In multiple regression model, PASI score was the only variable which was significantly associated with all HRQoL measures. Presence of exposed lesions was a significant factor affecting DLQI and SF-36 (mental).

CONCLUSION

The presence of exposed lesions has a negative impact on quality of life, mental health and work productivity. Therefore, effective treatments are particularly needed for psoriasis patients with exposed lesions.

Bupivacaine Induces Apoptosis via ROS in the Schwann Cell Line

Local anesthetics have been generally accepted as being safe. However, recent clinical trials and basic studies have provided strong evidence for the neurotoxicity of local anesthetics, especially through apoptosis. We hypothesized that local anesthetics cause neural complications through Schwann cell apoptosis. Among local anesthetics tested on the Schwann cell line, RT4-D6P2T, bupivacaine significantly induced cell death, measured by the methyl tetrazolium (MTT) assay, in a dose- (LD50 = 476 μM) and time-dependent manner. The bupivacaine-induced generation of reactive oxygen species (ROS), which was initiated within 5 hrs and preceded the activation of caspase-3 and poly ADP-ribose polymerase (PARP) degradation, was suggested to trigger apoptosis, exhibited by Hoechst 33258 nuclear staining and DNA fragmentation. Furthermore, concomitant block of ROS by anti-oxidants significantly inhibited bupivacaine-induced apoptosis. Among the local anesthetics for peripheral neural blocks, bupivacaine induced apoptosis in the Schwann cell line, which may be associated with ROS production.

What factors are associated with a second opioid prescription after treatment of distal radius fractures with a volar locking plate?

PURPOSE

Knowledge of factors associated with patient's requests for a second opioid prescription after volar plate fixation of a fracture of the distal radius might inform better pain management protocols and encourage decreased and safer use of opioids. This study tested the primary null hypothesis that there is no difference in demographics, prior opioid prescriptions, injury characteristics, and psychological factors between patients that do and do not receive a second opioid prescription following treatment volar locking plate after distal radius fracture.

PATIENTS AND METHODS

We used data on 206 patients enrolled in one of two prospective studies. Their mean age was 53 years ± SD 15, and 60 (30 %) were men. Forty-seven (23 %) patients received a second opioid prescription. We recorded additional demographics, AO fracture type, American Society for Anesthesiologists (ASA) classification, radiographic parameters at the time of injury prior to reduction and after surgery, and catastrophic thinking.

RESULTS

Male sex (odds ratio [OR] 2.2, 95 % confidence interval [CI] 1.0-4.6, partial pseudo R (2) = 0.018, P = 0.044) and greater dorsal angulation of the articular surface on the lateral post injury radiograph (OR 0.98, 95 % CI 0.96 to 1.0, partial pseudo R (2) = 0.033, P = 0.040) were associated with a second opioid prescription after surgery (pseudo R (2) 0.12, P = 0.0071).

CONCLUSIONS

One measure of fracture severity (dorsal displacement) was independently associated with a second opioid prescription, but alone it accounted for 3.3 % of the variation. Other factors such as the patient's expectation prior to surgery, in particular the realization that injury and surgery hurt, might be addressed in future research.

LEVEL OF EVIDENCE

Prognostic II.

Butyl paraben-induced changes in DNA methylation in rat epididymal spermatozoa

Parabens have been shown to affect male rodent reproductive parameters, including testosterone levels and sperm production. In this study, we examined the effect of long-term exposure to butyl paraben (BP) on rat epididymal sperm DNA methylation. Adult male rats were exposed to BP (0, 10, 100 and 1000 mg kg(-1) per day) according to OECD TG407 for a repeated 28-day oral toxicity study. Sperm DNA methylation was examined by differential display random amplification of polymorphic DNA (RAPD) following methylation-specific restriction digestion of DNA. Among the 57 RAPD amplicons, six were methylation specific. Of these, five amplicons increased by 1.4- to 3.8-fold in epididymal sperm DNA at testing dose of BP. This indicates that BP can cause DNA hypermethylation in germ cells from the mitotic through post-meiotic stage in adult rat testes. To our knowledge, this is the first report on the epigenetic modification of sperm DNA by parabens.

Efficient procurement of epithelial stem cells from human tissue specimens using a Rho-associated protein kinase inhibitor Y-27632

The efficient culture of stem cells from epithelial tissues such as skin and corneas is important for both experimental studies and clinical applications of tissue engineering. We now demonstrate that treatment of human-skin-derived keratinocytes with a Rho-associated protein kinase inhibitor Y-27632 for the initial 6 days of primary culture can increase the number of keratinocytes that possess stem cell properties to form colonies during in vitro culture of freshly isolated cells and subsequent passage (50-fold). Further, we show that Y-27632 treatment can increase the total number of prostate epithelial cells derived from human prostate specimens. Therefore, the use of Y-27632 during primary cultures offers a simple and effective way to prepare a large number of epithelial stem cells from various human epithelial tissues.

Establishment of a reference interval for natural killer cell activity through flow cytometry and its clinical application in the diagnosis of hemophagocytic lymphohistiocytosis

Recently, the Histiocyte Society revised the diagnostic criteria for hemophagocytic lymphohistiocytosis (HLH) to include low or absent natural killer (NK) cell activity, according to local laboratory reference. The aim of this study was to establish reference interval for functional NK-cell activity in 63 healthy Korean individuals using a flow-cytometric assay. We used peripheral blood mononuclear cells (PBMCs) as effector cells and Fluorescein isothiocyanate-labeled K562 cells as target cells. NK-cell activity was calculated using the following equation: NK-cell activity (%) = (test lysis - spontaneous lysis) x 100/(maximum lysis - spontaneous lysis). NK-cell activity was analyzed in 13 known HLH patients and 16 suspected non-HLH patients using a flow-cytometric assay. The mean (+/-SD) cytotoxicity of PBMCs from healthy individuals was 20.9 +/- 5.3% and the reference interval was 11.8-31.9%. The mean NK-cell activity of HLH patients (8.3 +/- 8.9%) was significantly lower (P = 0.001) than that of non-HLH patients (20.1 +/- 7.8%). The sequential changes in NK-cell activity in the HLH group corresponded to clinical and laboratory findings following treatment. We successfully developed a functional NK-cell activity test for use in the clinical laboratory and obtained a reference interval of NK-cell activity from healthy donors. This assay, and associated reference interval, was used to analyze 30 clinically relevant specimens and the results were shown to be well correlated.

Effects of molinate on survival and development of Bombina orientalis (Boulenger) embryos

Molinate, a thiocarbamate chemical is a slightly to moderately toxic herbicide in EPA (Environmental Protection Agency) toxicity class III, and is a registered as a General Use Pesticide (GUP). Bombina orientalis is one of the most common amphibians in the world and comprise a large proportion of their total number in Korea. B. orientalis spawns in the rice fields at spring when the massive application of agricultural chemicals occurs. In the present study, we examined the effects of molinate on embryonic survival and developmental abnormality in B. orientalis embryos. The difference in survival rate between vehicle control and molinate treated embryos was not observed until the blastula stage. The first statistically significant decrease in embryonic survival was observed at mouth open stage following exposure to 100 microM molinate (46.8% vs. 81.1% in control). When the embryos develop to tadpole stage survival was significantly decreased at 50 microM molinate (35.9% vs. 68.9% in control), suggesting that the lowest observed effective dose (LOED) for systemic toxicity in B. orientalis embryos is 50 microM. In survived embryos molinate exposure produced several types of severe developmental abnormalities in order of frequency with bent trunk, neurula with yolk plug, bent tail, tail dysplasia, ventral blister, eye dysplasia, thick-set body and cephalic dysplasia. This suggests that molinate targets multiple events in embryonic and larval development in this frog species. Together this suggested that molinate was detrimental for survival and development following zygotic transcription after midblastula transition in B. orientalis embryos.

Extended defect states of Ge/Si quantum dots using optical isothermal capacitance transient spectroscopy

We investigated the hole emission processes of optically induced charges on the defect states and confined states of self-assembled Ge quantum dots (QDs) embedded in a p-i-n Si diode. Optical deep level transient spectroscopy (ODLTS) and optical isothermal capacitance transient spectroscopy (OICTS) were used to study the defect states in ten stacked Ge quantum dots. Using ODLTS and OICTS for QD-embedded samples, the peaks related to the defect states of Ge QDs could be classified distinctly; it was about 20-50 times higher in intensity than that for the bulk defect states. The charges emitted from the QD defect state were observed near 93 K, and the activation energy was calculated to be E(V)+177 meV. The defect state followed the logarithmic capture kinetics and the Arrhenius-determined apparent activation energy decreased in the band gap as the optical injection width increased. We suggest that Ge QD defect states in Si could exist as extended states.

Expression of occludin in testis and epididymis of wild rabbits, Lepus sinensis coreanus

Tight junctions (TJs) in inter-Sertoli junctional areas and epididymal epithelia build up the blood-testis barrier (BTB) and the blood-epididymal barrier (BEB), respectively. In this study, the expression of occludin, an integral member of the TJs, was examined in testis and different regions of epididymis of Lepus sinensis coreanus, an Korean wild rabbit species. In testis, intense occludin immunoreactivity was found in the basally located inter-Sertoli junctional area together with diffused immunoreactivity of occludin in the cytoplasm of Sertoli cells. It can be suggested that occludin is one of the robust elements of BTB in seminiferous tubules of rabbit testis. In proximal and distal caput epididymis, occludin immunoreactivity was found in the lateral as well as apical contacts of epithelial cells. In corpus epididymis, intense occludin immunoreactivity was found in the basolateral as well as apical contacts of epithelial cells together with cytoplasmic signal. In cauda epididymis, occludin immunoreactivity in luminal epithelia was relatively strong but largely found in the cytoplasm. This suggests that intriguing regulatory mechanisms differentially recruit occludin to the TJ in the different regions of epididymal epithelia. The differences in the subcellular localization as well as expression levels of occludin among the epididymal segments may reflect differential paracellular permeability of epithelia along the epididymal tubules and be correlated with sperm maturation in rabbit. In Western blot, a major form of occludin was MW 62 kDa together with small fragments of MW 34-39 kDa in testis and epididymis, suggesting the peptide cleavage of occludin. This is the first report on the molecular nature of TJs in a wild rabbit testis and epididymis.

Investigation of the corticotropin-releasing hormone-proopiomelanocortin axis in various skin tumours

BACKGROUND

Various types of external stress cause the skin and central neuroendocrine system to express corticotropin-releasing hormone (CRH)-proopiomelanocortin (POMC) axis-related hormones. However, the precise role of the CRH-POMC axis-related hormones in various skin tumours is unclear.

OBJECTIVES

This study examined expression patterns of the CRH-POMC axis-related hormones in skin tumours.

METHODS

The production of CRH, adrenocorticotropic hormone (ACTH) and alpha-melanocyte-stimulating hormone (alpha-MSH) in various tumour cell lines including HaCaT and primary keratinocytes was examined using an enzyme-linked immunosorbent assay. Immunohistochemical analysis of the skin tumours was also performed.

RESULTS

CRH, ACTH and alpha-MSH were strongly expressed in malignant skin tumour cell lines such as G-361 and DX-3 (both malignant melanoma, MM). However, normal and haematological malignancy cell lines did not express the CRH-POMC axis-related hormones. Immunohistochemical analysis of the skin tumours showed that MM (80%), squamous cell carcinoma (SCC, 70%) and basal cell carcinoma (BCC, 10%) had strong immunoreactivity (++/+++) for CRH. Strong ACTH and alpha-MSH expression was observed in MM (70% and 50%, respectively), SCC (80% and 60%, respectively) and BCC (70% and 50%, respectively).

CONCLUSIONS

We report that an increase in the level of the CRH-POMC axis-related hormones is associated with malignant skin tumours such as MM. These results highlight the importance of the CRH-POMC axis-related hormones in the malignant tendency of skin tumours.

The mechanical properties and osteoconductivity of hydroxyapatite bone scaffolds with multi-scale porosity

The relative osteoconductivity and the change in the mechanical properties of hydroxyapatite (HA) scaffolds with multi-scale porosity were compared to scaffolds with a single pore size. Non-microporous (NMP) scaffolds contained only macroporosity (250-350 microm) and microporous (MP) scaffolds contained both macroporosity and microporosity (2-8 microm). Recombinant human bone morphogenetic protein-2 (rhBMP-2) was incorporated into all scaffolds via gelatin microspheres prior to implantation into the latissimus dorsi muscle of Yorkshire pigs. After 8 weeks, only the MP scaffolds contained bone. The result demonstrates the efficacy of the MP scaffolds as drug carriers. Implanted and as-fabricated scaffolds were compared using histology, microcomputed tomography, scanning electron microscopy, and compression testing. Implanted scaffolds exhibited a stress-strain response similar to that of cancellous bone with strengths between those of cancellous and cortical bone. The strength and stiffness of implanted NMP scaffolds decreased by 15% and 46%, respectively. Implanted MP scaffolds lost 30% of their strength and 31% of their stiffness. Bone arrested crack propagation effectively in MP scaffolds. The change in mechanical behavior is discussed and the study demonstrates the importance of scaffold microporosity on bone ingrowth and on the mechanical behavior of HA implant materials.

Therapeutic use of granulocyte-colony stimulating factor could conceal residual malignant cells in patients with AML1/ETO+ acute myelogenous leukemia

We have experienced a number of cases of AML1/ETO+ acute myelogenous leukemia that showed remission based on bone marrow (BM) morphological criteria, but that revealed clonal abnormalities in most cells by fluorescence in situ hybridization (FISH). Interestingly, most of these cases had AML with AML1/ETO rearrangement. The malignant cells were differentiated and considered mature cells after granulocyte-colony stimulating factor (G-CSF) treatment. To clarify the possible mechanisms underlying this phenomenon, we investigated the expression levels of G-CSFR in AML cells with AML1/ETO rearrangement by flow cytometry and real-time polymerase chain reaction (PCR). The number of AML1/ETO+ cells expressing G-CSFR at baseline was significantly higher than that of AML1/ETO- AML cells (2673 vs 522). In addition, the G-CSFR gene was more highly expressed in AML1/ETO+ cells than in AML1/ETO- cells by real-time PCR. This study reveals that cases showing remission after treatment with G-CSF mostly had leukemia with AML1/ETO rearrangement. This finding might be explained by the higher expression of G-CSF receptor in AML1/ETO+ cells than in AML1/ETO- cells. We recommend that remission should be confirmed by FISH, because malignant clones can be differentiated and masked in morphological examination or chromosome test, especially for AML with AML1/ETO rearrangement.

ESHAP plus G-CSF as an effective peripheral blood progenitor cell mobilization regimen in pretreated non-Hodgkin's lymphoma: comparison with high-dose cyclophosphamide plus G-CSF

The ESHAP (etoposide, methylprednisolone, high-dose cytarabine, and cisplatin) regimen has been shown to be effective as an active salvage therapy for lymphoma. Mobilizing stem cells following ESHAP should decrease time to transplantation by making separate mobilizing chemotherapy (MC) unnecessary, while controlling a patient's lymphoma. We therefore assessed the mobilization potential of ESHAP plus G-CSF in 26 patients (ESHAP group) with non-Hodgkin's lymphoma (NHL) and compared these results with those of 24 patients with NHL who received high-dose (4 g/m2l) cyclophosphamide (HDCY) as MC (HDCY group). The age, sex, and radiotherapy to the axial skeleton were well matched between groups, but the number of patients with poor mobilization predictors was higher in the ESHAP group. Significantly higher numbers of CD34+ cells (x 10(6)/kg) (17.1+/-18.8 vs 5.8+/-5.0, P=0.03) and apheresis day 1 CD34+ cells (x 10(6)/kg) (5.5+/-6.6 vs 1.7+/-2.0, P=0.014) were collected from the ESHAP group than from the HDCY group, and the number of patients who achieved an optimal CD34+ cell target of 5 x 10(6)/kg was higher in the ESHAP group (81 vs 50%, P=0.022). Log-rank test revealed that time to target peripheral blood progenitor cell collection (> or =5 x 10(6)/kg) was shorter in the ESHAP group (P=0.007). These results indicate that ESHAP plus G-CSF is an excellent mobilization regimen in patients with relapsed and poor-risk aggressive NHL.

Idiopathic Thrombocytopenic Purpura: Better Therapeutic Responses of Patients with B- or T-Cell Clonality than Patients without Clonality

Results of recent studies of the pathogenesis of idiopathic thrombocytopenic purpura (ITP) have suggested activated helper T-cells drive B-lymphocytes to produce antibodies. Twenty-eight children and 85 adults with ITP entered this study. We performed polymerase chain reaction (PCR) using framework III variable region (V(H) FRIII)- and joining region (J(H))-specific primers to analyze immunoglobulin heavy-chain gene rearrangement (IgH GR) for B-cell clonality. We used multiplex PCR to analyze T-cell receptor (TCR) gamma-chain gene rearrangement (TCRgamma GR) for T-cell clonality. We diagnosed 10 cases as acute ITP and 97 cases as chronic ITP. The IgH GR result was positive in 77.8% of the acute-form cases and in 58.8% of the chronic-form cases. The TCRgamma GR result was positive in 11.1% of the acute cases and in 10.6% of the chronic cases. There was no difference in frequency of clonality between the acute and chronic forms. After treatment the platelet count normalized in 81.8% (36/44) of the chronic ITP cases with B-cell clonality and in 88.9% (8/9) of the chronic ITP cases with T-cell clonality, compared with a normalized platelet count in 46.2% (12/26) of the chronic ITP cases without clonality. The patients with T- or B-cell clonality appeared to have better therapeutic responses than patients without clonality. In conclusion, T- and B-cell clonality may play a positive role in determining therapeutic response.

A case of biphenotypic blast crisis of unclassified myeloproliferative disorder

We report a first case of biphenotypic blast crisis of unclassified myeloproliferative disorder (MPD). A 20-year-old patient presented with fever, splenomegaly, marked leukocytosis (603 x 10(3)/ micro l), and blasts in the peripheral blood. Since Ph chromosome and bcr-abl gene rearrangement were absent, the diagnosis of an unclassified MPD in the blast crisis phase was established. Immunophenotyping confirmed a biphenotypic crisis of myeloid and T-lymphoid antigens. The patient went into a complete remission after chemotherapy, but marked granulocytic hyperplasia (M:E ratio of 5.7) and 90% cellularity remained. Blast crisis recurred during subsequent intensification chemotherapy and the patient did not go into a complete remission regardless of the intense chemotherapy. The blast crisis transformed from unclassified MPD had a grave prognosis as it responded poorly to chemotherapy. This unique blast crisis is distinguishable from the blast crisis of chronic myelogenous leukemia.

Induction of a pepper cDNA encoding SAR8.2 protein during the resistance response to tobacco mosaic virus

A cDNA library was constructed with mRNA extracted from TMV resistant hot pepper plants 24 and 48 h after inoculation by TMV. The library was screened differentially with radio-labeled cDNA synthesized with mRNA from the leaves of either TMV-inoculated or mock-inoculated hot pepper plants. CaSAR8.2 clone was one of the clones isolated by this differential screening. The predicted amino acid sequence of CaSAR8.2 has a homology of 52% similarity to that of tobacco SAR8.2 genes. Southern blot analysis showed that a multigene family of CaSAR8.2 was present in the hot pepper genome. Transcripts homologous to CaSAR8.2 accumulated abundantly in the leaves and the flowers, but little in other tissues. CaSAR8.2 gene expression was induced by avirulent pathotype TMV-P0 inoculation but not by virulent TMV-P1.2 inoculation. Effects of exogenously applied abiotic elicitors on CaSAR8.2 expression were also examined. Salicylic acid and ethephon treatments caused a rapid accumulation of CaSAR8.2 transcripts in pepper leaves and methyl jasmonate treatment slightly induced the expression of CaSAR8.2. A strain of Xanthomonas campestris pv. vesicatoria (Xcv) that contains an avirulence gene avrBs2, was infiltrated into the leaves of a pepper cultivar containing the Bs2 resistance gene. A marked induction of CaSAR8.2 gene expression was observed in Xcv-infiltrated leaves. These results suggest possible roles of CaSAR8.2 as pathogenesis-related protein against varieties of pathogens including virus and bacteria.

Mitochondrial protein phylogeny joins myriapods with chelicerates

The animal phylum Arthropoda is very useful for the study of body plan evolution given its abundance of morphologically diverse species and our profound understanding of Drosophila development. However, there is a lack of consistently resolved phylogenetic relationships between the four extant arthropod subphyla, Hexapoda, Myriapoda, Chelicerata and Crustacea. Recent molecular studies have strongly supported a sister group relationship between Hexapoda and Crustacea, but have not resolved the phylogenetic position of Chelicerata and Myriapoda. Here we sequence the mitochondrial genome of the centipede species Lithobius forficatus and investigate its phylogenetic information content. Molecular phylogenetic analysis of conserved regions from the arthropod mitochondrial proteome yields highly resolved and congruent trees. We also find that a sister group relationship between Myriapoda and Chelicerata is strongly supported. We propose a model to explain the apparently parallel evolution of similar head morphologies in insects and myriapods.

Spontaneous remission of aplastic anemia: a retrospective analysis

BACKGROUND AND OBJECTIVES

Although acquired aplastic anemia is usually a chronic disorder, a small proportion of patients with aplastic anemia was reported to recover spontaneously without specific therapy such as allogeneic bone marrow transplantation or immunosuppressive treatment. We attempted to determine the rate of spontaneous remission in the patients with AA.

DESIGN AND METHODS

We reviewed the medical records of adult patients (n=136) who were diagnosed as aplastic anemia at the Asan Medical Center from 1990 to 2000. The hematologic criteria of spontaneous remission were defined according to the proposed remission criteria of the SAA Working Party of the EBMT.

RESULTS

Eighteen (13%) of 136 patients satisfied the criteria for spontaneous remission at median 14 days (range, 4-332) from the diagnosis of aplastic anemia. In fifteen (83%) of 18 patients, spontaneous remission occurred within 50 days. Spontaneous remission was complete in fourteen patients (78%). Only two patients relapsed at 208 and 1,857 days after spontaneous remission, respectively. Multivariate logistic regression analysis showed that presence of infection at diagnosis (p = 0.017), drug as an etiology of aplastic anemia (p = 0.028), and serum albumin level less than 3.4 g/dL (p = 0.005) were independent predictive factors for spontaneous remission.

INTERPRETATION AND CONCLUSIONS

Our study confirmed that a minority of patients with AA recovered spontaneously. Spontaneous remission was rapid and complete in most patients, and relapses were rarely observed. In most cases with spontaneous remission, aplastic anemia might be associated with external factors such as drug or infection.

Sweet's syndrome during the treatment of acute promyelocytic leukemia with all-trans retinoic acid

All-trans retinoic acid (ATRA) is the standard induction treatment for acute promyelocytic leukemia (APL). Quite many ATRA-related side effects, including retinoic acid syndrome, were reported. So far, it has rarely been reported that Sweet's syndrome, characterized by fever, neutrophilia, painful erythematous cutaneous plaques, dense dermal infiltrates of mature neutrophils and rapid response to steroid therapy, is associated with ATRA. In the case that Sweet's syndrome associated with ATRA is found, physicians will have to face a great challenge over the possibility of infectious conditions. We present here a case of Sweet's syndrome associated with ATRA. A 35-year-old female with APL developed fever, painful erythematous cutaneous plaques on both cheeks, right wrist and both shins during induction chemotherapy with ATRA. A skin biopsy revealed a dense dermal infiltrate, consisting of mature neutrophils without vasculitis or cutaneous immunoglobulin deposits, which is compatible with Sweet's syndrome. Oral prednisone was administered and the lesions started to improve within 48 hours.

One-step PCR amplification of complete arthropod mitochondrial genomes

A new PCR primer set which enables one-step amplification of complete arthropod mitochondrial genomes was designed from two conserved 16S rDNA regions for the long PCR technique. For this purpose, partial 16S rDNAs amplified with universal primers 16SA and 16SB were newly sequenced from six representative arthropods: Armadillidium vulgare and Macrobrachium nipponense (Crustacea), Anopheles sinensis (Insecta), Lithobius forficatus and Megaphyllum sp. (Myriapoda), and Limulus polyphemus (Chelicerata). The genomic locations of two new primers, HPK16Saa and HPK16Sbb, correspond to positions 13314-13345 and 12951-12984, respectively, in the Drosophila yakuba mitochondrial genome. The usefulness of the primer set was experimentally examined and confirmed with five of the representative arthropods, except for A. vulgare, which has a linearized mitochondrial genome. With this set, therefore, we could easily and rapidly amplify complete mitochondrial genomes with small amounts of arthropod DNA. Although the primers suggested here were examined only with arthropod groups, a possibility of successful application to other invertebrates is very high, since the high degree of sequence conservation is shown on the primer sites in other invertebrates. Thus, this primer set can serve various research fields, such as molecular evolution, population genetics, and molecular phylogenetics based on DNA sequences, RFLP, and gene rearrangement of mitochondrial genomes in arthropods and other invertebrates.

Correlation of hematopoietic progenitor cell count determined by the SE-automated hematology analyzer with CD34(+) cell count by flow cytometry in leukapheresis products

The yield of stem cell collection after mobilization is crucial for autologous peripheral blood stem cell (PBSC) transplantation. Quantitative determinations of CD34(+) cells using flow cytometry or stem cell culture have been used, but these methods require much time, technical experience, and expensive reagents. The automated hematology analyzer (Sysmex SE-9000trade mark, TOA, Japan) equipped with the Immature Information (IMI) channel for immature myeloid cells can detect IMI(+) cells within 90 sec. Detection is made possible by the combination of a special reagent system and direct current/radiofrequency biosensors. We studied the relation of IMI(+) cells and variable cell counts with CD34(+) cell yield in autologous stem cell harvest. In a series of 32 patients (median age, 44 years; M:F = 11:21), 184 leukaphereses were performed after mobilization regimens with chemotherapy and G-CSF or G-CSF alone. Full blood cell counts were enumerated on peripheral blood (PB) samples taken prior to each leukapheresis. Mononuclear cell (MNC) and IMI(+) cell counts by automated hematology analyzer and flow cytometry based CD34(+) cell yield were measured on the harvested product. The relationship among PB white blood cells (WBC), PB monocytes, IMI(+) cells, MNC, and CD34(+) cell yield in a single leukapheresis was estimated by Pearson correlation analysis. PB WBC count showed no correlation with CD34(+) cell yield in a single leukapheresis (r = 0.02, P = 0.81). PB monocyte count showed a weak correlation (r = 0.21, P = 0.01) and MNC in harvest also showed a weak correlation (r = 0.36, P = 0.0001) with CD34(+) cell yield. In contrast, CD34(+) cell yield correlated well with IMI(+) cell count (r = 0.68, P = 0.0001), and data could be fitted by a linear regression equation, y = 0.330 + 0.974x. IMI(+) cell assay by the automated hematology analyzer correlated well with the CD34(+) cell yield in a mobilized autologous stem cell harvest. The IMI(+) cell count might be used as a simple and efficient indicator of blood stem cell mobilization and collection.

Overexpression of the tobacco Tsi1 gene encoding an EREBP/AP2-type transcription factor enhances resistance against pathogen attack and osmotic stress in tobacco

Using mRNA differential display analysis, we isolated a salt-induced transcript that showed a significant sequence homology with an EREBP/AP2 DNA binding motif from oilseed rape plants. With this cDNA fragment as a probe, cDNA clone Tsi1 (for Tobacco stress-induced gene1) was isolated from a tobacco cDNA library. RNA gel blot analysis indicated that transcripts homologous with Tsi1 were induced not only in NaCl-treated leaves but also in leaves treated with ethephon or salicylic acid. Transient expression analysis using a Tsi1::smGFP fusion gene in BY-2 cells indicated that the Tsi1 protein was targeted to the nucleus. Fusion protein of Tsi1 with GAL4 DNA binding domain strongly activated transcription in yeast, and the transactivating activity was localized to the 13 C-terminal amino acids of Tsi1. Electrophoretic mobility shift assays revealed that Tsi1 could bind specifically to the GCC and the DRE/CRT sequences, although the binding activity to the former was stronger than that to the latter. Furthermore, Agrobacterium-mediated transient expression and transgenic plants expressing Tsi1 demonstrated that overexpression of the Tsi1 gene induced expression of several pathogenesis-related genes under normal conditions, resulting in improved tolerance to salt and pathogens. These results suggest that Tsi1 might be involved as a positive trans-acting factor in two separate signal transduction pathways under abiotic and biotic stress.

A hot pepper cDNA encoding a pathogenesis-related protein 4 is induced during the resistance response to tobacco mosaic virus

Hot pepper (Capsicum annuum) plants exhibit a hypersensitive response (HR) against infection by many tobamoviruses. A clone (CaPR-4) encoding a putative pathogenesis-related protein 4 was isolated by differential screening of a cDNA library prepared from resistant pepper plant leaves inoculated with tobacco mosaic virus (TMV) pathotype P0. The predicted amino acid sequence of CaPR-4 is very similar to those of other plant PR-4s. Southern blot analysis showed that small gene families of PR-4-related sequences were present in the pepper genome. Hot pepper cultivar Bugang, resistant to TMV-P0 and susceptible to TMV-P1.2, induced CaPR-4 expression by pathotype P0 inoculation in inoculated and systemic leaves, but not by pathotype P1.2. Effects of exogenously applied abiotic elicitors upon the CaPR-4 expression were also examined. The expression of the CaPR-4 gene was stimulated by methyl jasmonate (MeJA), ethephon and wounding treatment. However, application of salicylic acid (SA) did not trigger the expression. Evidence is emerging that jasmonic acid and ethylene play key roles in the SA-independent pathways of plant-pathogen interaction. Taken together, these results suggest that the CaPR-4 gene is one of the defense-related genes conferring resistance on pepper plants by the SA-independent pathway and the cross-talk between signaling compounds, jasmonic acid and ethylene could have a great regulatory potential in a plant's defense against TMV.

Screening of hexavalent chromium biosorbent from marine algae

A highly chromate-selective biosorbent with high adsorption capacity was found by examining the chromate adsorption capacities of 48 species of red, brown, or green marine algae sampled from the east coast of Korea. As a result of screening, a red marine alga showed excellent adsorption characteristics. It was identified as Pachymeniopsis sp. The timing of the sampling of Pachymeniopsis sp. did not affect the adsorption capacity of the alga but the optimum period for mass collection was April-May. The alga also showed high selectivity for chromate and its adsorption capacity for other heavy metal ions such as cadmium and manganese was relatively low. An investigation of the adsorption isotherm of Pachymeniopsis sp. as a dried powder for chromate adsorption at 25 degrees C showed Langmuir-type dependence. The maximum chromate adsorption capacity of the selected alga was about 225 mg/g. The desorption of adsorbed chromate from Pachymeniopsis sp. was done by treating samples with 1 N NaOH. It was confirmed that ion exchange type adsorption was observed with anion exchangers but not with cation exchangers. Therefore it is believed that the chromate adsorption is based on the anionic exchange of Pachymeniopsis sp.

Prevalence of atopic dermatitis in Korea

This study was designed to estimate the prevalence and personal or family history of atopic dermatitis in school children in 3 areas of Korea: urban (Seoul), industrial (Ulsan) and rural (Chunchon). On the basis of dermatologists' physical examinations and the questionnaires completed by parents or guardians, the prevalence of atopic dermatitis was estimated to be 3.3% in the industrial area, 6.6% in the rural area and 7.8% in the urban area. The frequency of atopic dermatitis decreased with age and was significantly lower in the industrial area than in the rural and urban areas.

Characterization and cDNA cloning of two glycine- and histidine-rich antimicrobial peptides from the roots of shepherd's purse, Capsella bursa-pastoris

Two novel antimicrobial peptides were isolated and characterized from the roots of shepherd's purse, Capsella bursa-pastoris. These antimicrobial peptides, named shepherin I and shepherin II, consist of 28 and 38 amino acids, respectively, and are glycine- and histidine-rich peptides. Shepherin I and shepherin II have 67.9% and 65.8% (mol/mol) glycine, respectively, and 28.6% and 21.1% (mol/mol) histidine, respectively. Both shepherins have a Gly-Gly-His motif. These antimicrobial peptides exhibit antimicrobial activity against Gram-negative bacteria and fungi. Circular dichroism spectra of shepherin I and shepherin II showed that shepherin I and shepherin II in 50% trifluoroethanol have 66.7% and 75% random coils, respectively, without any alpha-helices. cDNA sequence analysis revealed that shepherin I and shepherin II are produced from a single polypeptide, designated shep-GRP, consisting of 120 amino acids; shep-GRP has five distinct domains, an amino-terminal putative signal peptide, a shepherin I, a linker dipeptide, a shepherin II and a carboxy-terminal peptide. Southern blot analysis indicates that the gene encoding shepherins belongs to a low-complexity gene family. Northern blot analysis revealed that transcripts of shep-GRP are present in roots but not in leaves and stems.