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Shock is common in critically ill and injured patients. Survival during shock is highly dependent on rapid restoration of tissue oxygenation with therapeutic goals based on cardiac output (CO) optimization. Despite the clinical availability of numerous minimally invasive monitors of CO, limited supporting performance data are available. Following approval of the University of Saskatchewan Animal Research Ethics Board, we assessed the performance and trending ability of PiCCOplus™, FloTrac™, and CardioQ-ODM™ across a range of CO states in pigs. In addition, we assessed the ability of invasive mean arterial blood pressure (iMAP) to follow changes in CO using a periaortic transit-time flow probe as the reference method. Statistical analysis was performed with function-fail, bias and precision, percent error, and linear regression at all flow, low-flow (> 1 standard deviation [SD] below the mean), and high-flow (> 1 SD above the mean) CO conditions. We made a total of 116,957 paired CO measurements. The non-invasive CO monitors often failed to provide a CO value (CardioQ-ODM: 40.6% failed measurements; 99% confidence interval [CI], 38.5 to 42.6; FloTrac: 9.6% failed measurements; 99% CI, 8.7 to 10.5; PiCCOplus: 4.7% failed measurements; 99% CI, 4.5 to 4.9; all comparisons, P < 0.001). The invasive mean arterial pressure provided zero failures, failing less often than any of the tested CO monitors (all comparisons, P < 0.001). The PiCCOplus was most interchangeable with the flow probe at all flow states: PiCCOplus (20% error; 99% CI, 19 to 22), CardioQ-ODM (25% error; 99% CI, 23 to 27), FloTrac (34% error; 99% CI, 32 to 38) (all comparisons, P < 0.001). At low-flow states, CardioQ-ODM (43% error; 99% CI, 32 to 63) and Flotrac (45% error; 99% CI, 33 to 70) had similar interchangeability (P = 0.07), both superior to PiCCOplus (48% error; 99% CI, 42 to 60) (P < 0.001). Regarding CO trending, the CardioQ-ODM (correlation coefficient, 0.82; 99% CI, 0.81 to 0.83) was statistically superior to other monitors including iMAP, but at low flows iMAP (correlation coefficient, 0.58; 99% CI, 0.58 to 0.60) was superior to all minimally invasive CO monitors (all comparisons P < 0.001). None of the minimally invasive monitors of CO performed well at all tested flows. Invasive mean arterial blood pressure most closely tracked CO change at critical flow states.

Postoperative vomiting (POV) in children is frequent. Dextrose-containing intravenous fluids in the perioperative period have shown improvement of POV in adults. Similar studies have not been done in children. The primary purpose was to study the efficacy of intraoperative intravenous dextrose for antiemetic prophylaxis in children undergoing ambulatory surgery. A non-inferiority randomized clinical trial of healthy children (three to nine years old) undergoing ambulatory dental surgery was conducted. The control group received dexamethasone (0.15 mg·kg−1 iv) and ondansetron (0.05 mg·kg−1 iv); the intervention group received dexamethasone (0.15 mg·kg−1 iv) and intravenous 5% dextrose in 0.9% normal saline according to a weight-based maintenance rate. The primary outcome was POV in the postanesthetic care unit (PACU) within two hr after surgery. Secondary outcomes included POV within 24 hr from discharge and unplanned hospital admission. A non-inferiority analysis was conducted on the primary outcome using an absolute risk difference of 7.5% as the non-inferiority margin. Data from 290 patients were analyzed. Demographics and intraoperative anesthetic management were similar between groups. Vomiting in the PACU occurred in 7.6% and 3.5% of the dextrose and ondansetron groups, respectively, with a risk difference of 4.2% (95% confidence interval [CI], -1.0 to 9.5). Given that the upper limit of the 95% CI exceeded our non-inferiority margin, non-inferiority of dextrose compared with ondansetron was not shown. These results do not support the use of intravenous dextrose as a satisfactory alternative to ondansetron to prevent POV in ambulatory pediatric dental surgery patients. www.clinicaltrials.gov (NCT 01912807); registered 18 July 2013.

This interactive session was held at the 51st Annual Meeting of the Canadian Association of Pediatric Surgeons (CAPS) in preparation for the transition of Pediatric Surgery training in Canada to Competency by Design (a CBME-based model of residency training developed by the Royal College of Physicians and Surgeons of Canada).

Substance abuse remains a serious public health crisis, affecting millions of people worldwide. Macrocyclic tetrapeptides like CJ-15,208 and [d-Trp]CJ-15,208 demonstrate opioid activity shown to attenuate the rewarding effects of cocaine in conditioned place preference assays in mice, making them promising lead compounds for treating substance abuse. In the present study, we report the rational design, synthesis, conformational analysis, and continued pharmacological evaluation of the novel macrocyclic tetrapeptide cyclo[Pro-Sar-Phe-d-Phe] to further explore this unique molecular scaffold. This peptide was rationally designed based on X-ray and NMR structures of related macrocyclic tetrapeptides. Following synthesis, its solution-phase conformations were determined by NMR and molecular modeling. The peptide adopted multiple conformations in polar solvents, but a single conformation in chloroform that is stabilized by intramolecular hydrogen bonding. The peptide is orally bioavailable, producing antinociception and antagonism of kappa opioid receptor (KOR) stimulation following oral administration in a mouse 55 °C warm-water tail-withdrawal assay. Notably, cyclo[Pro-Sar-Phe-d-Phe] blocked both stress- and drug-induced reinstatement of cocaine and morphine conditioned place preference in mice following oral administration, and displayed a decreased side-effect profile compared to morphine. Thus, cyclo[Pro-Sar-Phe-d-Phe] is a promising lead compound for the treatment of substance abuse.

Background: Neonates on long-term parenteral nutrition (PN) may develop parenteral nutrition-associated liver disease (PNALD). Aluminum (Al) is a known contaminant of infant PN, and we hypothesize that it substantially contributes to PNALD. In this study, we aim to assess the impact of Al on hepatocytes in a piglet model. Methods: We conducted a randomized control trial using a Yucatan piglet PN model. Piglets, aged 3-6 days, were placed into two groups. The high Al group (n=8) received PN with 63 µg/kg/day of Al, while the low Al group (n=7) received PN with 24 µg/kg/day of Al. Serum samples for total bile acids (TBA) were collected over two weeks, and liver tissue was obtained at the end of the experiment. Bile canaliculus morphometry was studied by transmission electron microscopy (TEM) and Image-J software analysis. In December 2019, the American Academy of Pediatrics issued a key technical report on Al effects in infants and children. This report was revised and commented on in this chapter. Results: The canalicular space was smaller, and the microvilli were shorter in the high Al group than in the low Al group. There was no difference in the TBA between the groups. Conclusions: Al causes structural changes in the hepatocytes despite unaltered serum bile acids. High Al in PN is associated with short microvilli, which could decrease the functional excretion area of the hepatocytes and impair bile flow. Long-term toxicity studies from the Al content in PN components supported the US Food and Drug Administration (FDA) in the decision to implement specific rules. It has been required that large-volume ingredients reduce the Al concentration and all small volume components be specifically labeled with the Al concentration. However, both US FDA and we consider that despite these rules, the total Al concentration from some components remains above the recommended final concentration. US FDA and our concerns about toxicity from the Al present in infant PN formulas are grounded, requiring more research on this topic.

Rationale Cognitive problems are common in adults with epilepsy and significantly affect their quality of life. HOBSCOTCH (HOme Based Self-management and COgnitive Training CHanges lives) was developed to teach problem-solving and compensatory memory strategies to these individuals. This study examined whether HOBSCOTCH is associated with improvement in specific aspects of subjective executive functions. Methods Fifty-one adults, age 18–65, with epilepsy and subjective cognitive concerns were randomized to receive HOBSCOTCH (n = 31) or a care-as-usual control sample (n = 20). Participants completed the Behavior Rating Inventory of Executive Function-Adult version (BRIEF-A), as well as the Patient Health Questionnaire-9 (PHQ-9) to assess depression. Rates of elevated (i.e., T ≥ 65, impaired) BRIEF-A scores at baseline, as well as pre-post score changes for the BRIEF-A clinical scales were evaluated. Significance was set at α = 0.05, one-tailed, given our directional hypothesis. Results At baseline, a considerable percentage of patients in the overall sample endorsed executive dysfunction on BRIEF-A scales: Inhibit = 28%, Shift = 51%, Emotional Control = 45%, Self-Monitor = 33%, Initiate = 35%, Working Memory = 88%, Plan/Organize = 45%, Task Monitor = 47%, Organization of Materials = 28%. Significant improvement was seen in mean T-scores for Inhibit, Shift, Initiate, and Working Memory in the treatment group, but only Working Memory improved in the control group. The control group endorsed worse task monitoring and organization of materials at baseline and follow-up. Change in depression was not observed for either group, and there was no association between changes in depression and BRIEF-A scores. Conclusions A sizeable subset of adults with epilepsy reported experiencing executive dysfunction in their everyday lives, especially for working memory. HOBSCOTCH resulted in amelioration of subjective executive functioning independent of changes in mood.

BACKGROUND AND PURPOSE: The macrocyclic tetrapeptide natural product CJ‐15,208 (cyclo[Phe‐d‐Pro‐Phe‐Trp]) is a multifunctional μ‐opioid receptor and κ‐opioid receptor agonist and κ‐opioid receptor antagonist that produces antinociception and prevents stress‐induced reinstatement of extinguished cocaine‐conditioned place preference (CPP). We hypothesized that an analogue of CJ‐15,208, cyclo[Pro‐Sar‐Phe‐d‐Phe], would demonstrate multifunctional μ‐opioid receptor and κ‐opioid receptor ligand activity, producing potent antinociception with fewer liabilities than selective μ‐opioid receptor agonists, while preventing both drug‐ and stress‐induced reinstatement of morphine‐induced CPP. EXPERIMENTAL APPROACH: The opioid receptor agonist and antagonist activity of cyclo[Pro‐Sar‐Phe‐d‐Phe] was characterized after i.c.v. and i.p. administration to C57BL/6J or transgenic opioid receptor “knockout” mice using the 55°C warm‐water tail‐withdrawal assay. Liabilities of locomotor coordination, respiration and spontaneous ambulation, and direct rewarding or aversive properties were assessed. Finally, the ability of cyclo[Pro‐Sar‐Phe‐d‐Phe] to block morphine‐ and stress‐induced reinstatement of extinguished CPP was determined. KEY RESULTS: cyclo[Pro‐Sar‐Phe‐d‐Phe] demonstrated dose‐dependent, short‐lasting antinociception, with an ED(50) (and 95% confidence interval) of 0.15 (0.05–0.21) nmol i.c.v. and 1.91 (0.40–3.54) mg·kg(−1) i.p., mediated by μ‐ and κ‐opioid receptors. The macrocyclic tetrapeptide also demonstrated potent dose‐dependent κ‐opioid receptor antagonist‐like activity at 2.5, but not at 4.5, h after administration. cyclo[Pro‐Sar‐Phe‐d‐Phe] displayed reduced liabiities compared with morphine, attributed to its additional activity at κ‐receptors. Pretreatment with cyclo[Pro‐Sar‐Phe‐d‐Phe] prevented stress‐ and drug‐induced reinstatement of extinguished morphine‐place preference responses in a time‐dependent manner. CONCLUSIONS AND IMPLICATIONS: These data suggest that cyclo[Pro‐Sar‐Phe‐d‐Phe] is a promising lead compound for both the treatment of pain with reduced sideeffects and preventing both drug‐ and stress‐induced relapse in morphine‐abstinent subjects.

The reactivity of skin microcirculation was compared in 3 groups of patients. Group 1 included healthy volunteers without cardiovascular diseases (n = 19), Group 2 included patients with diseases that increase the risk of cardiovascular events (arterial hypertension and / or angina pectoris and / or diabetes mellitus) (n = 40), Group 3 included patients with a history of cardiovascular events (myocardial infarction and / or stroke and / or coronary revascularization) (n = 20). Microcirculation measurement was performed by Laser Doppler flowmetry using LAKK 02 device during the heating test. Patients from Group 2 had a decrease in the reactivity of skin microcirculation compared with the control group, while the reactivity of skin microcirculation in these patients was better than in patients from Group 3. The highest difference was observed for the Slope_180 parameter (slope of the regression line of the microcirculation curve for the first 180 seconds of heating). Using the machine learning we developed a method for classifying patients into Group 1, Group 2, Group 3 according to the Slope_180 parameter. The sensitivity and specificity of Slope_180 parameter in identifying patients with cardiovascular diseases, diabetes (groups 2 and 3 together) was 82% and 68%, respectively. Such methods may be a promising for health screening. Thus, the relationship between the severity of skin microcirculation disorders and the “severity” of cardiovascular disease demonstrates the prospect of studying microcirculatory disorders as a cardiovascular risk factor.

During the first week of life, a sudden deterioration in a newborn commonly includes investigations to rule out infections, lung pathologies, cardiac lesions, neurological insults, metabolic disorders or gastrointestinal emergencies. It is unusual, however, to consider malignancy as the primary causative factor. In this case report, we describe a rare and unusual presentation of congenital hepatoblastoma, its complications and management in a neonate with multi-organ dysfunction. A term infant presented with sudden deterioration, hemodynamic instability and an acute abdomen on his 4th day of life. Surgical exploration revealed a ruptured neoplasm that pathology diagnosed as a congenital hepatoblastoma. After the patient was stabilized, chemotherapy was initiated. At present, the patient is 8 months old and under continuous follow-up of oncology service. This case highlights the importance of considering rare diagnoses including congenital malignancy when investigating and managing a sick newborn with multi-organ dysfunction.

Congenital urachal anomalies are usually asymptomatic. However, infection or obstruction of urachal remnant may result in serious complications. The giant umbilical cords with suspected internal communications could contain remnants and require surgical exploration. With timely recognition and surgical intervention, the outcome is generally good.

Aluminum toxicity is associated with anemia, impaired bone metabolism, neurologic defects, and parenteral nutrition (PN)-associated liver disease. This element is a ubiquitous contaminant of PN components, especially in infant formulations. We assessed the current levels of aluminum contamination in infant PN at a level III neonatal intensive care unit.Thirty samples of PN prepared in the same hospital for infants aged30 days (mean [SD] weight, 1.54 [0.71] kg) were collected from discarded solution. Each sample was analyzed for aluminum content via inductively coupled plasma mass spectrometry. The components of PN (from label) and measured aluminum content were then compared using linear regression and 1-way analysis of variance.The mean (SD) aluminum contamination of infant PN was 14.02 (6.51) mcg/kg/d. Only 3 samples were5 mcg/kg/d. Aluminum levels and infant weight were not associated. Linear regression revealed a significant correlation between aluminum and both calcium gluconate ( P.0001) and phosphate ( P = .05), with a trend between aluminum and potassium ( P = .07).Aluminum contamination in infant PN remains almost 3 times higher than the advised maximum exposure (5 mcg/kg/d, Food and Drug Administration 2004). Unexpectedly, an association between infant weight and aluminum exposure was not apparent, likely due to the homogeneity of our population. Isolating the source of aluminum contamination is difficult, as multiple components appear to be involved. Calcium gluconate is likely still a major contributor, but further investigations into individual components are warranted to promote the reduction of aluminum in infant PN.

Chest pain can be a challenging complaint to manage in the emergency department. A missed diagnosis can result in significant morbidity or mortality, whereas avoidable testing and hospitalizations can lead to increased health care costs, contribute to hospital crowding, and increase risks to patients. The HEART score is a validated decision aid to identify patients at low risk for acute coronary syndrome who can be safely discharged without admission or objective cardiac testing. In the largest and one of the longest studies to date (N = 31,060; 30 months), we included the HEART score into a larger, newly developed low-risk chest pain decision pathway, using a retrospective observational pre/post study design with the objective of safely lowering admissions. The modified HEART score calculation tool was incorporated in our electronic medical record. A significant increase in discharges of low-risk chest pain patients (relative increase of 21%; p < 0.0001) in the postimplementation period was observed with no significant difference in the rates of major adverse cardiac events between the pre and post periods. There was a decrease in the amount of return admissions for 30 days (4.65% fewer; p = 0.009) and 60 days (3.78% fewer; p = 0.020). No significant difference in length of stay was observed for patients who were ultimately discharged. A 64% decrease in monthly coronary computed tomography angiograms was observed in the post period (p < 0.0001). These findings support the growing consensus in the literature that the adoption of the HEART pathway or similar protocols in emergency departments, including at large and high-volume medical institutions, can substantially benefit patient care and reduce associated health care costs.

Background: Neonates on long-term parenteral nutrition (PN) may develop parenteral nutrition-associated liver disease (PNALD). Aluminum (Al) is a known contaminant of infant PN, and we hypothesize that it substantially contributes to PNALD. In this study, we aim to assess the impact of Al on hepatocytes in a piglet model. Methods: We conducted a randomized control trial using a Yucatan piglet PN model. Piglets, aged 3&ndash, 6 days, were placed into two groups. The high Al group (n = 8) received PN with 63 &micro, g/kg/day of Al, while the low Al group (n = 7) received PN with 24 &micro, g/kg/day of Al. Serum samples for total bile acids (TBA) were collected over two weeks, and liver tissue was obtained at the end of the experiment. Bile canaliculus morphometry were studied by transmission electron microscopy (TEM) and ImageJ software analysis. Results: The canalicular space was smaller and the microvilli were shorter in the high Al group than in the low Al group. There was no difference in the TBA between the groups. Conclusions: Al causes structural changes in the hepatocytes despite unaltered serum bile acids. High Al in PN is associated with short microvilli, which could decrease the functional excretion area of the hepatocytes and impair bile flow.

Background There is significant lack of information regarding the Canadian pediatric surgery workforce. Methods An IRB-approved survey aimed at assessing workforce issues was administered to pediatric surgeons and pediatric surgery chiefs in Canada in 2012. Results The survey was completed by 98% of practicing surgeons and 13 of the 18 division chiefs. Only 6% of surgeons are older than 60years, and only a fifth anticipate retirement over the next decade. The workforce is stable, with 82% of surgeons unlikely to change current positions. Surgical volume showed essentially no growth during the 5-year period 2006–2010. The majority of surgeons felt they were performing the right number or too few cases and anticipated minimal or no future growth in their individual practices or that of their group. Based on anticipated vacancies, the best estimate is a need for 20 new pediatric surgeons over the next decade. This need is significantly surpassed by the current output from the Canadian training programs. Conclusions The Canadian pediatric surgery workforce is currently saturated. The mismatch between the number of graduating trainees and the available positions over the next decade has significant repercussions for current surgery and pediatric surgery residents wishing to practice in Canada.

Purpose Biomechanical evidence has demonstrated that the running interlocking horizontal mattress (RIHM) repair for extensor tendon lacerations is significantly stronger, with higher ultimate load to failure and less tendon shortening compared with other techniques. We investigated the efficacy and safety of primary extensor tendon repair using the RIHM repair technique in the fingers followed by the immediate controlled active motion protocol, and in the thumb followed by a dynamic extension protocol. Methods We conducted a retrospective review of all patients undergoing extensor tendon repair from August 2009 to April 2012 by single surgeon in an academic hand surgery practice. The inclusion criteria were simple extensor tendon lacerations in digital zones IV and V and thumb zones TI to TIV and primary repair performed using the RIHM technique. We included 8 consecutive patients with 9 tendon lacerations (3 in the thumb). One patient underwent a concomitant dorsal hand rotation flap for soft tissue coverage. We used a 3–0 nonabsorbable braided suture to perform a running simple suture in 1 direction to obtain a tension-free tenorrhaphy, followed by an RIHM corset-type suture using the same continuous strand in the opposite direction. Average time to surgery was 10 days (range, 3–33 d). Mean follow-up was 15 weeks (range, 10–26 wk). We applied the immediate controlled active motion protocol to all injuries except those in the thumb, where we used a dynamic extension protocol instead. Results Using the criteria of Miller, all 9 tendon repairs achieved excellent or good results. There were no tendon ruptures or extensor lags. No patients required secondary surgery for tenolysis or joint release. No wound complications occurred. Conclusions The RIHM technique for primary extensor tendon repairs in zone IV and V and T1 to TIV is safe, allows for immediate controlled active motion in the fingers and an immediate dynamic extension protocol in the thumb, and achieves good to excellent functional outcomes. These clinical outcomes support prior biomechanical data. Type of study/level of evidence Therapeutic IV.

Purpose Patent Ductus Arteriosus (PDA) ligation in premature infants is an urgent procedure performed by some but not all pediatric surgeons. Proficiency in PDA ligation is not a requirement of Canadian pediatric surgery training. Our purpose was to determine the outcomes of neonatal PDA ligation done by pediatric surgeons. Methods We performed a retrospective review of premature infants who underwent PDA ligation by pediatric surgeons in 3 Canadian centers from 2005 to 2009. Outcomes were compared to published controls. Results The review identified 98 patients with a mean corrected GA and weight at repair of 29weeks and 1122g, respectively. There were no intraoperative deaths. The 30-day and inhospital mortality rates were 1% and 5%. Mortality and morbidity were comparable to the published outcomes. Conclusions This study documents that a significant number of preterm infant PDA ligations are safely done by pediatric surgeons. To meet the Canadian needs for this service by pediatric surgeons, proficiency in PDA ligation should be considered important in pediatric surgery training programs.

Introduction: A subpopulation of sickle-cell disease patients, termed super-utilizers, present frequently to emergency departments (EDs) for vaso-occlusive events and may consume disproportionate resources without broader health benefit. To address the health care needs of this vulnerable patient population, we piloted a multidisciplinary intervention seeking to create and use individualized patient care plans that to alter utilization through coordinated care. Our goals were to assess feasibility primarily, and to assess resource use secondarily. Methods: We evaluated the effects of a single-site interventional study targeted at a population of adult sickle-cell disease super-utilizers using a pre- and post-implementation design. The pre-intervention period was 06/01/13 to 12/31/13 (7 months) and the post-intervention period was 01/01/14 to 02/28/15 (14 months). Our approach included: patient-specific best practice advisories (BPA); an ED management protocol (figure 1); formation of a "medical home" for these patients. Results: For 10 subjects targeted initially we developed and implemented coordinated care plans; after deployment, we observed a tendency toward reduction in ED and inpatient utilization across all measured indices. Between the annualized pre- and post-implementation periods: ED visits decreased by 16.5 visits/pt-yr (95% CI, -1.32 to 34.2); ED length of state (LOS) decreased by 115.3 hours/pt-yr (95% CI, -82.9 to 313.5); in-patient admissions decreased by 4.20 admissions/pt-yr (95% CI, -1.73 to 10.1); in-patient LOS decreased by 35.8 hours/pt-yr (95% CI, -74.9 to 146.7); and visits where the patient left before treatment was reduced by an annualized total of 13.7 visits. We observed no patient mortality in our 10 subjects and no patient required admission to the ICU care 72 hours following discharge. Conclusion: This effort suggests that a targeted approach is both feasible and potentially effective, laying a foundation for broader study.

Traumatic brain injury (TBI) is a challenging disease process, both to treat and investigate. Broadly speaking, TBI consists of structural injuries or physiologic changes in brain function secondary to external forces. Such injuries may result in cell death, gliotic scar formation, and/or damage from reactive oxygen species and inflammation.Prior TBI population studies revealed that the prevalence of TBI in adults over 18 was 8.5%. In 2010, 2.5 million emergency department visits, hospitalizations, and deaths were associated with TBI with data from the Centers for Disease Control and Prevention suggesting that TBI was related to 30% of mortalities. Pediatric TBI, while largely understudied, is also an important concern, as it can reach an annual incidence of 100,000–200,000 with children between the ages of 0 and 4 years having the highest percentage of incidence and mortality., The economic impact of brain injury is difficult to determine when considering compensation for work loss, quality of life, rehabilitation, and home services in addition to medical costs. Nonetheless, estimates of total lifetime costs range from $147 billion for fatal TBI to $18 billion for nonhospitalized TBI.Although brain injuries are a significant portion of trauma, the severity of TBI ranges from mild, defined as a momentary change in consciousness, to severe, which involves sustained periods of unconsciousness and/or amnesia. Fortunately, more than 85% of TBI that is medically treated is considered mild and most patients are able to recover from their injuries.

Traumatic brain injury (TBI) remains a significant source of death and permanent disability, contributing to nearly one-third of all injury-related deaths in the United States and exacting a profound personal and economic toll.Despite the increased resources that have recently been brought to bear to improve our understanding of TBI, the development of new diagnostic and therapeutic approaches has been disappointingly slow.Translational Research in Traumatic Brain Injury attempts to integrate expertise from across specialties to address knowledge gaps in the field of TBI. Its chapters cover a wide scope of TBI research in five broad areas: • Epidemiology • Pathophysiology • Diagnosis • Current treatment strategies and sequelae • Future therapies Specific topics discussed include the societal impact of TBI in both the civilian and military populations, neurobiology and molecular mechanisms of axonal and neuronal injury, biomarkers of traumatic brain injury and their relationship to pathology, neuroplasticity after TBI, neuroprotective and neurorestorative therapy, advanced neuroimaging of mild TBI, neurocognitive and psychiatric symptoms following mild TBI, sports-related TBI, epilepsy and PTSD following TBI, and more.The book integrates the perspectives of experts across disciplines to assist in the translation of new ideas to clinical practice and ultimately to improve the care of the brain-injured patient.

Elastin-like polypeptide (ELP) is a bioengineered protein widely applied as a drug carrier due to its biocompatibility and amenability to modification with cell-penetrating peptides (CPPs) and therapeutic agents. The purpose of this study was to determine whether topically applied ELP or CPP-fused ELPs penetrate the corneal barrier.In vitro binding and cytotoxicity to human corneal epithelial (HCE) cells were determined for ELP or CPP-ELPs. Corneal binding, clearance, and penetration were assessed in a rabbit model following topical application of the fluorescently labeled proteins by quantitative fluorescence imaging and histology.ELP bound to HCE cells in vitro, and binding/uptake was enhanced 2- to 3-fold by the addition of CPPs. When applied topically to rabbit eyes, ELP accumulated in the cornea at levels 7.4-fold higher than did an equivalent dose of immunoglobulin G. Both ELP and a CPP-ELP penetrated the corneal epithelium and were detectable in the stroma. Addition of CPPs to ELP, however, did not significantly enhance corneal uptake or penetration in vivo relative to ELP alone. The polypeptides cleared from the cornea over a period of 20-30 min after application, after which cornea levels reached a steady state of 15-30 μg/mL for up to 3 h.The ELP drug carrier can penetrate the corneal epithelium and accumulate in the stroma. Given its amenability for fusion to multiple types of therapeutic agents, ELP has the potential to serve as a drug carrier for topical ocular applications.

Background Thoracoscopic sympathicotomy is highly effective in treating disabling palmar hyperhidrosis. The ideal level to maximize efficacy and minimize the side effect of compensatory hyperhidrosis (CH) is controversial. This study compared sympathicotomy over the second (R2) vs third (R3) costal head relative to these variables in patients with massive palmar hyperhidrosis. Methods This prospective, randomized study enrolled 121 patients with disabling palmoplantar hyperhidrosis assigned to bilateral sympathicotomy (sympathetic transection), which was done over R2 in 61 (n = 122 extremities) or R3 in 60 (n = 120 extremities). Patients were questioned at 6 months and at 1 year or more to assess efficacy, side effects, and satisfaction with the procedure. Results Sympathicotomy at R2 failed to cure palmar hyperhidrosis in 5 of 122 (4.1%) extremities, but only 2 (1.6%) were to a truly profound dripping level of recurrence. Sympathicotomy at R3 failed to cure palmar hyperhidrosis in 5 of 120 extremities (4.2%), and all were dramatic failures with dripping recurrent sweating. The patients whose palmar hyperhidrosis was not completely cured were aged 19.7 ± 2.5 vs 26.4 ± 8.0 years ( p = 0.04). Two R3 patients with failure underwent three redo R2 sympathicotomies, with curative results. R2 patients showed a trend toward a higher level of CH vs R3 patients at 6 months and after 1 year. The CH severity scale was 4.7 ± 2.7 (n = 38) for R2 vs 3.8 ± 2.8 (n = 36) for R3 ( p = NS) at 6 months and 4.7 ± 2.5 (n = 43) for R2 vs 3.7 ± 2.8 (n = 37) for R3 ( p = NS) after 1 year. Younger age, male sex, and higher levels of preoperative and postoperative plantar sweating were predictors of failed sympathicotomy. Increased age was associated with increased CH. Conclusions R2 and R3 sympathicotomy for massive palmoplantar hyperhidrosis are highly effective, with low recurrence and incidences of severe CH. R2 tends to have a higher level of CH vs R3, and a higher incidence of dramatic failures is suggested in R3 patients, for which reoperation at the R2 level will likely be curative.

Purpose: Parenteral nutrition–associated cholestasis remains a significant problem, especially for the surgical neonate. Aluminum is a toxic element known to contaminate parenteral nutrition. We hypothesize that parenterally administered aluminum causes liver injury similar to that seen in parenteral nutrition–associated cholestasis. Methods: Twenty 3- to 6-day-old domestic pigs were divided into 5 equal groups. A control group received daily intravenous 0.9% sodium chloride. Each subject in experimental groups received intravenous aluminum chloride at 1500 μg/kg per day for 1, 2, 3, or 4 weeks. At the end of the study, blood was sampled for direct bilirubin and total bile acid levels. Liver, bile, and urine were sampled for aluminum content. Liver tissue was imaged by transmission electron microscopy for ultrastructural changes. Results: Transmission electron microscopy revealed marked blunting of bile canaliculi microvilli in all experimental subjects but not the controls. Serum total bile acids correlated with the duration of aluminum exposure. The hepatic aluminum concentration correlated with the duration of aluminum exposure. Conclusions: Parenterally infused aluminum resulted in liver injury as demonstrated by elevated bile acids and by blunting of the bile canaliculi microvilli. These findings are similar to those reported in early parenteral nutrition–associated liver disease.

Epac2 is a cAMP-regulated guanine nucleotide exchange factor (cAMP-GEF) that is proposed to mediate stimulatory actions of the second messenger cAMP on mouse islet insulin secretion. Here we have used methods of islet perifusion to demonstrate that the acetoxymethyl ester (AM-ester) of an Epac-selective cAMP analog (ESCA) penetrates into mouse islets and is capable of potentiating both first and second phases of glucose-stimulated insulin secretion (GSIS). When used at low concentrations (1-10 μM), 8-pCPT-2'-O-Me-cAMP-AM activates Rap1 GTPase but exhibits little or no ability to activate protein kinase A (PKA), as validated in assays of in vitro PKA activity (phosphorylation of Kemptide), Ser (133) CREB phosphorylation status, RIP1-CRE-Luc reporter gene activity, and PKA-dependent AKAR3 biosensor activation. Since quantitative PCR demonstrates Epac2 mRNA to be expressed at levels ca. 5.3-fold greater than that of Epac1, available evidence indicates that Epac2 does in fact mediate stimulatory actions of cAMP on mouse islet GSIS.

To ascertain the identities of cyclic nucleotide-binding proteins that mediate the insulin secretagogue action of cAMP, the possible contributions of the exchange protein directly activated by cAMP (Epac) and protein kinase A (PKA) were evaluated in a pancreatic beta cell line (rat INS-1 cells). Assays of Rap1 activation, CREB phosphorylation, and PKA-dependent gene expression were performed in combination with live cell imaging and high throughput screening of a fluorescence resonance energy transfer-based cAMP sensor (Epac1-camps) to validate the selectivity with which acetoxymethyl esters (AM-esters) of cAMP analogs preferentially activate Epac or PKA. Selective activation of Epac or PKA was achieved following exposure of INS-1 cells to 8-pCPT-2′-O-Me-cAMP-AM or Bt2cAMP-AM, respectively. Both cAMP analogs exerted dose-dependent and glucose metabolism-dependent actions to stimulate insulin secretion, and when each was co-administered with the other, a supra-additive effect was observed. Because 2.4-fold more insulin was secreted in response to a saturating concentration (10 μm) of Bt2cAMP-AM as compared with 8-pCPT-2′-O-Me-cAMP-AM, and because the action of Bt2cAMP-AM but not 8-pCPT-2′-O-Me-cAMP-AM was nearly abrogated by treatment with 3 μm of the PKA inhibitor H-89, it is concluded that for INS-1 cells, it is PKA that acts as the dominant cAMP-binding protein in support of insulin secretion. Unexpectedly, 10–100 μm of the non-AM-ester of 8-pCPT-2′-O-Me-cAMP failed to stimulate insulin secretion and was a weak activator of Rap1 in INS-1 cells. Moreover, 10 μm of the AM-ester of 8-pCPT-2′-O-Me-cAMP stimulated insulin secretion from mouse islets, whereas the non-AM-ester did not. Thus, the membrane permeability of 8-pCPT-2′-O-Me-cAMP in insulin-secreting cells is so low as to limit its biological activity. It is concluded that prior reports documenting the failure of 8-pCPT-2′-O-Me-cAMP to act in beta cells, or other cell types, need to be re-evaluated through the use of the AM-ester of this cAMP analog.

This study reports preliminary findings for total phenolics, flavonoids, ascorbic acid, reducing potential, and radical scavenging of pawpaw pulp extracts from underripe, ripe, and overripe fruits. Total phenolics were affected by ripeness {underripe = ripe > overripe}, as were flavonoids (ripe

Recently we demonstrated that PLC(epsilon) plays an important role in beta-adrenergic receptor (betaAR) stimulation of Ca(2+)-induced Ca(2+) release (CICR) in cardiac myocytes. Here we have reported for the first time that a pathway downstream of betaAR involving the cAMP-dependent Rap GTP exchange factor, Epac, and PLC(epsilon) regulates CICR in cardiac myocytes. To demonstrate a role for Epac in the stimulation of CICR, cardiac myocytes were treated with an Epac-selective cAMP analog, 8-4-(chlorophenylthio)-2'-O-methyladenosine-3',5'-monophosphate (cpTOME). cpTOME treatment increased the amplitude of electrically evoked Ca(2+) transients, implicating Epac for the first time in cardiac CICR. This response is abolished in PLC(epsilon)(-/-) cardiac myocytes but rescued by transduction with PLC(epsilon), indicating that Epac is upstream of PLC(epsilon). Furthermore, transduction of PLC(epsilon)(+/+) cardiac myocytes with a Rap inhibitor, RapGAP1, significantly inhibited isoproterenol-dependent CICR. Using a combination of cpTOME and PKA-selective activators and inhibitors, we have shown that betaAR-dependent increases in CICR consist of two independent components mediated by PKA and the novel Epac/(epsilon) pathway. We also show that Epac/PLC(epsilon)-dependent effects on CICR are independent of sarcoplasmic reticulum loading and Ca(2+) clearance mechanisms. These data define a novel endogenous PKA-independent betaAR-signaling pathway through cAMP-dependent Epac activation, Rap, and PLC(epsilon) that enhances intracellular Ca(2+) release in cardiac myocytes.

Penetrating traumatic brain injury (pTBI) remains one of the most devastating and lethal forms of trauma. Prognosis is generally poor and, for those who survive long enough to make it to the hospital, the management of penetrating brain injury presents complex challenges to medical and surgical providers in the civilian sector. Recent experiences in Operation Iraqi Freedom and Operation Enduring Freedom have provided opportunities to study and refine the surgical and medical management of pTBIs that may impact civilian evaluation and management of similar traumas. These experiences demonstrated that aggressive pre-hospital and emergency department resuscitation, followed by immediate surgical management and post-operative intensive care to monitor for and intervene on surgical and medical complications could significantly improve patient outcomes. We begin with a brief case vignette that will introduce a comprehensive discussion on the epidemiology, pathophysiology, evolution of current surgical and medical therapies, complications, and prognostic indicators that may improve outcomes in these challenging cases.

Using peripheral venous pressure (PVP) instead of central venous pressure (CVP) as a volume monitor decreases patient risks and costs, and is convenient. This study was undertaken to determine if PVP predicts CVP in pediatric patients. With ethical approval and informed consent, 30 pediatric patients aged neonate to 12 yr requiring a central venous line were studied prospectively in a tertiary care teaching hospital. In the supine position, PVP and CVP were simultaneously transduced. Ninety-six paired recordings of CVP and PVP were made. Correlation and Bland-Altman analysis of agreement of end-expiratory measurements were performed. The mean (SD; range) CVP was 10.0 mmHg (6.0; −1.0 to 27.0); the mean PVP was 13.7 mmHg (6.3; 0.0 to 33.0); offset (bias) of PVP > CVP was 3.7 mmHg with SD 2.6. The 95% confidence intervals (CI) for the bias were 3.2 to 4.1 mmHg. In the Bland-Altman analysis, lower and upper limits of agreement (LOA; CI in parentheses) were −1.5 (−2.3 to −0.7) and 8.8 (8.1 to 9.6) mmHg. Eight of 96 points were outside the limits of agreement. The correlation of PVP on CVP was r = 0.92,P < 0.0001. For a subset of ten patients (20 simultaneous recordings) withiv atheters proximal to the hand, limits of agreement were better — offset: 3.8 mmHg (± 1.4); lower LOA: 1.2 mmHg (0.25 to 2.1); upper LOA: 6.6 mmHg (5.7 to 7.5). Peripheral venous pressure measured from aniv catheter in the hand predicts CVP poorly in pediatric patients.

Nephrotic syndrome, a malfunction of the kidney glomerular filter, leads to proteinuria, edema and, in steroid-resistant nephrotic syndrome, end-stage kidney disease. Using positional cloning, we identified mutations in the phospholipase C epsilon gene (PLCE1) as causing early-onset nephrotic syndrome with end-stage kidney disease. Kidney histology of affected individuals showed diffuse mesangial sclerosis (DMS). Using immunofluorescence, we found PLCepsilon1 expression in developing and mature glomerular podocytes and showed that DMS represents an arrest of normal glomerular development. We identified IQ motif-containing GTPase-activating protein 1 as a new interaction partner of PLCepsilon1. Two siblings with a missense mutation in an exon encoding the PLCepsilon1 catalytic domain showed histology characteristic of focal segmental glomerulosclerosis. Notably, two other affected individuals responded to therapy, making this the first report of a molecular cause of nephrotic syndrome that may resolve after therapy. These findings, together with the zebrafish model of human nephrotic syndrome generated by plce1 knockdown, open new inroads into pathophysiology and treatment mechanisms of nephrotic syndrome.

Phospholipase C (PLC) ε is a recently identified enzyme regulated by a wide range of molecules including Ras family small GTPases, Rho A, Gα 12/13 , and Gβγ with primary sites of expression in the heart and lung. In a screen for human signal transduction genes altered during heart failure, we found that PLCε mRNA is upregulated. Two murine models of cardiac hypertrophy confirmed upregulation of PLCε protein expression or PLCε RNA. To identify a role for PLCε in cardiac function and pathology, a PLCε-deficient mouse strain was created. Echocardiography indicated PLCε −/− mice had decreased cardiac function, and direct measurements of left ventricular contraction demonstrated that PLCε −/− mice had a decreased contractile response to acute isoproterenol administration. Cardiac myocytes isolated from PLCε −/− mice had decreased β-adrenergic receptor (βAR)-dependent increases in Ca 2+ transient amplitudes, likely accounting for the contractile deficiency in vivo. This defect appears to be independent from the ability of the βAR system to produce cAMP and regulation of sarcoplasmic reticulum Ca 2+ pool size. To address the significance of these functional deficits to cardiac pathology, PLCε −/− mice were subjected to a chronic isoproterenol model of hypertrophic stress. PLCε −/− mice were more susceptible than wild-type littermates to development of hypertrophy than wild-type littermates. Together, these data suggest a novel PLC-dependent component of βAR signaling in cardiac myocytes responsible for maintenance of maximal contractile reserve and loss of PLCε signaling sensitizes the heart to development of hypertrophy in response to chronic cardiac stress.

Objective To evaluate the pattern of clinical results in patients with neurogenic thoracic outlet syndrome (N-TOS) after operative decompression and longitudinal follow-up. Methods From May 1994 to December 2002, 254 operative sides in 185 patients with N-TOS were treated by the same operative protocol: (1) transaxillary first rib resection and the lower part of scalenectomy for the primary procedure with or without (2) the subsequent upper part of scalenectomy with supraclavicular approach for patients with persistent or recurrent symptoms. This retrospective cohort study included 38 men and 147 women with an age range of 19 to 80 years (mean, 40 years). Evaluated were primary success, defined as uninterrupted success with no procedure performed, and secondary success, defined as success maintained by the secondary operation after the primary failure. Success was defined as ≥50% symptomatic improvement judged by the patient using a 10-point scale, returning to preoperational work status, or both. Results Follow-up was 2 to 76 months (mean, 25 months). Eighty sides underwent a secondary operation for the primary clinical failure. No technical failures and no deaths occurred ≤30 days after the operations. The complication rate was 4% (13/334) and consisted of 7 pneumothoraxes, 3 subclavian vein injuries, 1 nerve injury, 1 internal mammary artery injury, and 1 suture granuloma. Of 254 operative sides, the primary and secondary success was 46% (118/254) and 64% (163/254). Most the primary failures (90%, 122/136) and the secondary failures (66%, 23/35) occurred ≤18 months after the respective operation. Conclusions The long-term results of operations for TOS in this study were much worse than those initially achieved, and most of the primary and secondary failures occurred ≤12 months of the respective operations. A minimum of 18-month follow-up on patients and standardized definition of the outcomes are necessary to determine the true effectiveness and outcome of operative treatment of N-TOS.

Parenteral nutrition (PN) is an essential component in the care of premature and ill infants. The incidence of parenteral nutrition-associated cholestasis (PNAC) ranges from 7.4 to 84%. One substance in PN solutions that has been implicated in PNAC is aluminum. Aluminum loading in animals and humans causes hepatic accumulation and damage. The degree of aluminum contamination of PN solutions has decreased over time, but contamination still significantly exceeds levels that are safe for human neonates. Further study into the relationship between aluminum contamination in neonatal PN solutions and the development of PNAC is necessary.

Estrogen deficiency following ovariectomy or menopause results in bone loss. Although evidence strongly suggests that the immune system is involved in the pathogenesis of estrogen-deficient osteoporosis, it is not clear what role, if any, the T-lymphocyte plays in this process. Therefore, we examined the distribution of T-cell subsets in lymphoid organs and tissues, under varying estrogenic states in the rat. Six-month-old female Sprague-Dawley rats, ovariectomized (Ovx) and sham-operated, were randomized 5 d post-surgery into six groups to receive the following treatments: (A) sham/placebo; (B) sham/low-dose E2; (C) sham/high-dose E2; (D) Ovx/placebo; (E) Ovx/low-dose E2; (F) Ovx/high-dose E2. Half of the treated rats (groups A-F) were sacrificed on d 14; the remainder on d 28. Following euthanasia, mononuclear cells were isolated from the thymus, peripheral blood, spleen, lymph node and bone marrow, and were labeled for flow cytometric analysis using mouse anti-rat monoclonal antibodies directed against CD5, CD4, and CD8 antigenic markers. In the thymus, ovariectomy caused a dramatic increase and E2 treatment caused a dose-dependent decrease in weight that was proportional to the number of thymocytes. In the bone marrow, ovariectomy caused a significant reduction in the percentage of all T-cell subsets examined and this effect persisted throughout the duration of the study. Estrogen replacement therapy at the low-dose reversed the effects of ovariectomy and high-dose E2 treatment caused an increase in T-cell subsets in both the sham and Ovx groups, an effect that was more pronounced at d 14 compared with d 28. Although the percentages of some T-cell subsets in the other lymphoid organs/tissues were altered by ovariectomy or E2 treatment at d 0 and 14, all these changes had normalized by d 28 except for CD5 and CD4 cells in peripheral blood. In summary, with the exception of T-lymphocytes in the bone marrow, the effects of varying estrogenic states on T-cells were variable and transient. The influence of estrogen status on bone marrow T-lymphocytes suggests that these cells may play a role in mediating the effects of estrogen on bone turnover and warrant additional studies focusing on the functional role of T-cells in the bone marrow compartment.

The induction of apoptosis in thymocytes by the glucocorticoid dexamethasone was used as a model system to investigate whether there are changes in 20 S and 26 S proteasome activities during apoptosis. We observed that thymocytes contain high concentrations of proteasomes and that following treatment with dexamethasone, cell extracts showed a decrease in proteasome chymotrypsin-like activity which correlated with the degree of apoptosis observed. The decrease in chymotrypsin-like activity of 20 S and 26S proteasomes was still apparent after these complexes had been partially purified from apoptotic thymocyte extracts and was therefore not due to competition resulting from a general increase in protein turnover. The trypsin-like and peptidylglutamylpeptide hydrolase activities of proteasome complexes were also observed to decrease during apoptosis, but these decreases were reversed by the inhibition of apoptosis by the caspase inhibitor benzyloxycarbonyl-Val-Ala-Asp(OMe)-fluoromethylketone. However, the chymotrypsin-like activity of proteasomes decreased further in the presence of the apoptosis inhibitor. Val-Ala-Asp-fluoromethylketone was found to inhibit the chymotrypsin- and trypsin-like activity of 26 S proteasomes in vitro. The decrease in proteasome activities in apoptosis did not appear to be due to a decrease in the concentration of total cellular proteasomes. Thus, the early decreases in 20 S and 26 S proteasome activities during apoptosis appear to be due to a down-regulation of their proteolytic activities and not to a decrease in their protein concentration. These data suggest that proteasomes may be responsible, in thymocytes, for the turnover of a protein that functions as a positive regulator of apoptosis.

A 3-week-old premature female infant was referred to our institution with progressively worsening respiratory distress. She was born at 29 weeks’ gestational age with radiologic evidence of mild respiratory distress syndrome. She required only minimal supplemental oxygen until her third week of life, when she developed worsening respiratory distress requiring mechanical ventilation. A new chest radiograph (Fig. 1) demonstrated hyperinflation of the left hemithorax with coarse reticular markings throughout the left lung. Computed tomography (CT; Fig. 2) revealed innumerable cystic spaces of varying sizes occupying the entirety of the left upper lobe, with no appreciable normal lung parenchyma interposed. She failed to wean from mechanical ventilation and underwent an urgent left thoracotomy. The entire upper lobe was grossly involved with cystic lung pathology (Fig. 3). This was treated by an uncomplicated left upper lobectomy, and the patient was weaned from mechanical ventilation over the next 3 days. The histopathology (Fig. 4) demonstrated cyst-like cavities lined by an irregular layer of cells within the lung parenchyma. These cells were mostly mononuclear admixed with foreign body–type multinucleated giant cells. The cysts were interspersed with essentially normal-appearing pulmonary tissue. Occasional air spaces were questionably dilated, particularly at the periphery of the lung beneath the pleural surface. However, widespread emphysematous changes were not apparent; neither was there any significant intraalveolar or interstitial inflammatory cell infiltrate. These findings were diagnosed as localized persistent pulmonary interstitial em

The heavy metal cadmium causes nephrotoxicity and alters the transport function of epithelial cells. In the shark rectal gland, chloride secretion is regulated by secretagogues and inhibitors acting through receptors coupled to G proteins and the cyclic AMP-protein kinase A pathway. We examined the effects of cadmium on the response to the inhibitory peptide somatostatin (SRIF), and to the stimulatory secretagogues forskolin and vasoactive intestinal peptide (VIP). In control experiments, SRIF (100 nM) entirely inhibited the chloride secretory response to 10 μM forskolin (maximum chloride secretion with forskolin 1984 ± 176 μEq/h/g; with forskolin + SRIF 466 ± 93 μEq/h/g, P < 0.001). Cadmium (25 μM) entirely reversed the inhibitory response to SRIF (chloride secretion 2143 ± 222 μEq/h/g) and caused an overshoot (2917 ± 293 μEq/h/g) that exceeded the response to forskolin (P < 0.01). Cadmium also enhanced forskolin-stimulated chloride secretion (2628 ± 418 vs. 1673 ± 340 μEq/h/g, P < 0.02) and reversed the declining phase of the forskolin response. Cadmium had a concentration-dependent, biphasic effect on the response to VIP. Cd (10–100 μM) increased both chloride secretion and tissue cyclic AMP content, whereas higher concentrations (1 mM) inhibited chloride secretion and cyclic AMP accumulation. Our findings provide evidence that Cd disrupts the signal transduction pathways of both inhibitory receptors and secretagogues regulating cAMP mediated transport in an intact epithelia. The results are consistent with direct effects of cadmium on adenylate cyclase and/or phosphodiesterase activity in this marine epithelial model. J. Exp. Zool. 279:530–536, 1997. © 1997 Wiley-Liss, Inc.

The ability of glucose and carbachol, alone or in combination, to stimulate islet cell phosphoinositide (PI) hydrolysis and insulin secretory responses in freshly isolated or in 20-24 h cultured rat islets was assessed. In freshly isolated, 3H-inositol-prelabeled islets, 20 mM glucose alone or 1 mM carbachol alone stimulated significant increments in 3H-inositol efflux and inositol phosphate (IP) accumulation. When stimulated with both agonists, a dramatic and synergistic effect on IP accumulation was noted. Carbachol (1 mM) alone had no sustained stimulatory effect on insulin secretion. Glucose (20 mM) alone induced a biphasic insulin secretory response. When compared to prestimulatory secretory rates of 18 +/- 4 pg/islet/min, peak first and second phase responses now averaged 422 +/- 61 and 1016 +/- 156 pg/islet/min, respectively. In contrast to freshly studied islets, culturing islets for 20-24 h in CMRL-1066 medium attenuated all measured responses. The increases in 3H-inositol efflux rates in response to glucose, carbachol, or their combination were significantly less than those observed with fresh islets. The IP responses were also attenuated. Second phase insulin secretory responses to 20 mM glucose alone 68 +/- 9 pg/islet/min) or the combination of 20 mM glucose plus 1 mM carbachol (358 +/- 85 pg/islet/min) were also significantly decreased when compared with fresh islets. We conclude from these studies that the process of culturing islets for one day in CMRL-1066 significantly decreases islet cell PI hydrolysis and insulin secretory responsiveness. These observations may help to explain the discordant conclusions reached concerning the involvement of PI hydrolysis and protein kinase C activation in the regulation of insulin release from freshly isolated versus cultured islets.

We characterize a mechanism of injury, injury pattern, and treatment algorithm for adductor pollicis myotendinous injuries in 2 professional baseball players. Similar to myotendinous eccentric injuries in other anatomical areas, the adductor pollicis sustains a sudden forceful eccentric load during a jammed swing, resulting in intramuscular strain or tendon rupture. Based on the reported injury mechanism, and magnetic resonance imaging features of these myotendinous injuries, the thumb of the top hand during a jammed swing was suddenly and forcefully eccentrically abducted from a contracted and adducted position, resulting in injury patterns.

Purpose Parenteral nutrition–associated cholestasis remains a significant problem, especially for the surgical neonates. Aluminum is a toxic element known to contaminate parenteral nutrition. We hypothesize that parenterally administered aluminum causes liver injury similar to that seen in parenteral nutrition–associated cholestasis. Methods Twenty 3- to 6-day-old domestic pigs were divided into 5 equal groups. A control group received daily intravenous 0.9% NaCl. Each subject in experimental groups received intravenous aluminum chloride at 1500 μ g kg −1 d −1 for 1, 2, 3, or 4 weeks. At the end of the study, blood was sampled for direct bilirubin and total bile acid levels. Liver, bile, and urine were sampled for aluminum content. Liver tissue was imaged by transmission electron microscopy for ultrastructural changes. Results Transmission electron microscopy revealed marked blunting of bile canaliculi microvilli in all experimental subjects but not the controls. Serum total bile acids correlated with the duration of aluminum exposure. The hepatic aluminum concentration correlated with the duration of aluminum exposure. Conclusions Parenterally infused aluminum resulted in liver injury as demonstrated by elevated bile acids and by blunting of the bile canaliculi microvilli. These findings are similar to those reported in early parenteral nutrition–associated liver disease.

Purpose: The aim of this study was to document the experience and patient satisfaction with providing pediatric surgery consultations and follow-up appointments to remote locations via audiovisual telecommunications technology. Methods: From January 2000 to April 2001, 16 consecutive pediatric general surgery clinics were reviewed for the type of patient (new or review), the diagnosis, the adequacy and accuracy of the evaluation, and the ability to formulate a plan. In the first year, first-time users were requested to complete a satisfaction survey of 15 questions. Responses to 13 questions were recorded on a 4-point Likert scale, and 2 questions required a "yes" or "no" response. Results: One hundred eighteen appointments were scheduled. Twenty patients did not show up or cancelled. There were 45 new patient consultations. Thirty-three patients were scheduled for surgery, of which, 21 are completed, and 12 are pending. There were no errors in diagnosis or changes in planned procedures. There were 42 patients seen in 53 follow-up sessions. Thirty-six surveys of a possible 53 were available for analysis. The mean rating of overall treatment experience at Telehealth was 3.47 (95% confidence interval 0.17). One hundred percent responded they would use Telehealth again and would recommend it to another person. Conclusion: Telehealth is an effective and acceptable way to provide pediatric general surgery clinics to remote locations. J Pediatr Surg 37:752-754. Copyright 2002, Elsevier Science (USA). All rights reserved.

To define a role for phospholipase C∈ (PLC∈) signaling in cardiac myocyte hypertrophic growth, PLC∈ protein was depleted from neonatal rat ventricular myocytes (NRVMs) using siRNA. NRVMs with PLC∈ depletion were stimulated with endothelin (ET-1), norepinephrine, insulin-like growth factor-1 (IGF-1), or isoproterenol and assessed for development of hypertrophy. PLC∈ depletion dramatically reduced hypertrophic growth and gene expression induced by all agonists tested. PLC∈ catalytic activity was required for hypertrophy development, yet PLC∈ depletion did not reduce global agonist-stimulated inositol phosphate production, suggesting a requirement for localized PLC activity. PLC∈ was found to be scaffolded to a muscle-specific A kinase anchoring protein (mAKAPβ) in heart and NRVMs, and mAKAPβ localizes to the nuclear envelope in NRVMs. PLC∈-mAKAP interaction domains were defined and overexpressed to disrupt endogenous mAKAPβ-PLC∈ complexes in NRVMs, resulting in significantly reduced ET-1-dependent NRVM hypertrophy. We propose that PLC∈ integrates multiple upstream signaling pathways to generate local signals at the nucleus that regulate hypertrophy.

Serial block face imaging is a microscopy technique in which the top of a specimen is cut or ground away and a mosaic of images is collected of the newly revealed cross-section. Images collected from each slice are then digitally stacked to achieve three-dimensional images. The development of fully-automated image acquisition devices has made serial block face imaging more attractive by greatly reducing labor requirements. The technique is particularly attractive for studies of biological activity within cancellous bone as it has the capability of achieving direct, automated measures of biological and morphological traits and their associations with one another. When used with fluorescence microscopy, serial block face imaging has the potential to achieve 3D images of tissue as well as fluorescent markers of biological activity. Epifluorescence-based serial block face imaging presents a number of unique challenges for visualizing bone specimens due to noise generated by subsurface signal and local variations in tissue autofluorescence. Here we present techniques for processing serial block face images of trabecular bone using a combination of non-uniform illumination correction, precise tiling of the mosaic in each cross-section, cross-section alignment for vertical stacking, removal of subsurface signal, and segmentation. The resulting techniques allow examination of bone surface texture that will enable 3D quantitative measures of biological processes in cancellous bone biopsies.