Does prophylactic antibiotics post pediatric pyeloplasty reduce the incidence of febrile UTIs?

PURPOSE

The use of postoperative prophylactic antibiotics in pediatric upper urinary tract reconstruction remains controversial. In this study, we examined whether low dose antibiotics administered following pediatric pyeloplasty reduce the incidence of febrile urinary tract infections at our institution. As a secondary outcome, in those patients with infection, additional analysis was performed to better quantify which patient population benefits the most from low dose prophylactic antibiotics.

METHODS

Institutional review board approval (IRB) was obtained. All methods were carried out in accordance with relevant guidelines and regulations. A retrospective study was performed in patients who underwent pyeloplasty (2011-2017) at our institution. Surgical approach (laparoscopic versus robotic assisted versus open, with or without internal JJ ureteral stent) were based on surgeon preference. Patients of 8 fellowship trained pediatric urologists were included in the study period. Patients with prior history of urologic interventions or other congenital genitourinary tract abnormalities were excluded. Demographics (age, gender, ethnicity, insurance status), prior history of culture proven urinary tract infection, surgical details (administration of perioperative antibiotics), and postoperative outcomes including; 1) re-admission 30 days post-surgery, 2) any urine cultures collected due to suspected urinary tract infection.

RESULTS

A total of 209 patients (149 boys, 60 girls) met our inclusion criteria with 55/209 (26%) receiving postoperative prophylactic antibiotics. The average age was 6 years (range: 2 months-18 years). Indwelling ureteral stent was used in 176 (84%) patients. Eleven patients (5%) had a culture-proven urinary tract infection within 30-days postoperatively. No significant differences were seen in postoperative complications or incidence of urinary tract infection when comparing surgical approaches, +/- ureteral stent, or the use of antibiotics. Secondary analysis noted statistically significant increase in post-operative urinary tract infection in younger children (2.8 v. 6.2 years, p = 0.02), those patients who had a positive preoperative urine culture (8/11, p = 0.01) and those with public health insurance (p = 0.038).

CONCLUSION

The incidence of postoperative urinary tract infection following pyeloplasty in our cohort was relatively low. There was a higher incidence of urinary tract infection in patients less than 3 years old. The use of antibiotics in patients post pyeloplasty did not appear to affect the incidence of post-operative urinary tract infection, however, they may have a role in children who have not yet potty trained and in patients with positive preoperative urine culture.

A magnetic hydrogel for the efficient retrieval of kidney stone fragments during ureteroscopy

Only 60-75% of conventional kidney stone surgeries achieve complete stone-free status. Up to 30% of patients with residual fragments <2 mm in size experience subsequent stone-related complications. Here we demonstrate a stone retrieval technology in which fragments are rendered magnetizable with a magnetic hydrogel so that they can be easily retrieved with a simple magnetic tool. The magnetic hydrogel facilitates robust in vitro capture of stone fragments of clinically relevant sizes and compositions. The hydrogel components exhibit no cytotoxicity in cell culture and only superficial effects on ex vivo human urothelium and in vivo mouse bladders. Furthermore, the hydrogel demonstrates antimicrobial activity against common uropathogens on par with that of common antibiotics. By enabling the efficient retrieval of kidney stone fragments, our method can lead to improved stone-free rates and patient outcomes.

Cost comparison of intra-detrusor injection of botulinum toxin versus augmentation cystoplasty for refractory neurogenic detrusor overactivity in children

INTRODUCTION

Treatment options for refractory neurogenic detrusor overactivity (NDO) in children include botulinum toxin type A (BTX-A) and augmentation cystoplasty (AC). Although BTX-A is accepted in contemporary pediatric urologic practice, cost and long-term outcomes data for BTX-A are limited relative to the gold standard, AC. The purpose of this study was to compare the projected 10-year costs of AC versus BTX-A.

METHODS

We performed a cost analysis from the payer perspective by computationally modeling treatment sequences by a Markov model. In the model, we used probabilities derived from published sources, and costs obtained at a tertiary medical center. The base case was a pediatric patient with refractory NDO. In the model, we assumed biannual BTX-A treatments. Treatment costs over 10 years were compared between immediate AC versus bridging therapy with BTX-A. Using the computational model, we simulated 100,000 instances of 10-year treatment cost for each of the two treatment modalities. The costs for the two treatment approaches were then compared using t-test and Wilcoxon test.

RESULTS

The projected median and mean 10-year cost of immediately AC were $51,798.72 (95% CI [$51,798.72, $327,483.80]) and $123,473.4 (SD: $98,085.23) respectfully, while the projected median and mean 10-year cost of bridging therapy with BTX-A prior to proceeding to AC as needed were $74,552.46 (95% CI [$53,188.56, $309,913.07]) and $124,858.80 (SD: $84,495.35) (p < 0.001).

CONCLUSIONS

For a typical index pediatric patient with NDO, bridging therapy with intravesical BTX-A is associated with an increased cost compared to immediate AC over a ten-year period.

The Value of Surgical Data-Impact on the Future of the Surgical Field

The combination of computing power, connectivity, and big data has been touted as the future of innovation in many fields, including medicine. There has been a groundswell of companies developing tools for improving patient care utilizing healthcare data, but procedural specialties, like surgery, have lagged behind in benefitting from data-based innovations, given the lack of data that is well structured. While many companies are attempting to innovate in the surgical field, some have encountered difficulties around collecting surgical data, given its complex nature. As there is no standardized way in which to interact with healthcare systems to purchase these data, the authors attempt to characterize the various ways in which surgical data are collected and shared. By surveying and conducting interviews with various surgical technology companies, at least 3 different methods to collect surgical data were identified. From this information, the authors conclude that an attempt to outline best practices should be undertaken that benefits all stakeholders.

Telehealth Adoption Across Neurosurgical Subspecialties at a Single Academic Institution During the COVID-19 Pandemic

Objective

The COVID-19 pandemic has dramatically changed health care, forcing providers to adopt and implement telehealth technology to provide continuous care for their patients. Amid this rapid transition from in-person to remote visits, differences in telehealth utilization have arisen among neurosurgical subspecialties. In this study, we analyze the impact of telehealth on neurosurgical healthcare delivery during the COVID-19 pandemic at our institution and highlight differences in telehealth utilization across different neurosurgical subspecialties.

Methods

To quantify differences in telehealth utilization, we analyzed all outpatient neurosurgery visits at a single academic institution. Internal surveys were administered to neurosurgeons and to patients to determine both physician and patient satisfaction with telehealth visits. Patient Likelihood-to-Recommend Press-Ganey scores were also evaluated.

Results

There was a decrease in outpatient visits during the COVID-19 pandemic in all neurosurgical subspecialties. Telehealth adoption was higher in spine, tumor, and interventional pain than in functional, peripheral nerve, or vascular neurosurgery. Neurosurgeons agreed that telehealth was an efficient (92%) and effective (85%) methodology; however, they noted it was more difficult to evaluate and bond with patients. The majority of patients were satisfied with their video visits and would recommend video visits over in-person visits.

Conclusions

During the COVID-19 pandemic, neurosurgical subspecialties varied in adoption of telehealth, which may be due to the specific nature of each subspecialty and their necessity to perform in-person evaluations. Telehealth visits will likely continue after the pandemic as they can improve clinical efficiency; overall, both patients and physicians are satisfied with health care delivery over video.

Preoperative Bladder Bowel Dysfunction Is the Most Important Predictive Factor for Postoperative Urinary Retention After Robot-Assisted Laparoscopic Ureteral Reimplantation via An Extravesical Approach: A Multi-Center Study

Introduction: Postoperative acute urinary retention (pAUR) is a known occurrence after robot-assisted laparoscopic ureteral reimplantation via an extravesical approach (RALUR-EV). We hypothesized that the risk factor of pAUR after RALUR-EV might be similar to that of pAUR after open reimplantation. We aimed at performing a retrospective multi-institutional study to evaluate the risk factors for pAUR after RALUR-EV. Materials and Methods: Perioperative data collected from two tertiary referral hospitals included demographics and perioperative variables such as bladder bowel dysfunction (BBD) status, vesicoureteral reflux (VUR) grade, and laterality. pAUR was defined as the need for urethral catheter replacement after removal of the initial postoperative catheter. Univariate and multivariate analyses were performed to identify risk factors for pAUR. Results: A total of 117 patients with 174 renal units from the 2 hospitals were enrolled in this study. The median age at the time of surgery was 5 (0.3-19) years. Bilateral RALUR-EV was performed in 57 (48.7%) cases. pAUR rate was 3.4% in all patients and 7.0% in 57 patients with bilateral VUR. All four cases of pAUR occurred after bilateral surgery. Univariate analysis showed age (p = 0.037), weight (p = 0.039), height (p = 0.040), and bilaterality (p = 0.037) as risk factors of pAUR. In a multivariate analysis, BBD was the only significant risk factor of pAUR (p = 0.037). Conclusion: Urinary retention after RALUR-EV occurred less frequently when compared with the previously reported open surgery series. pAUR was seen only in bilateral cases in our series. Preoperative history of BBD, but not male gender or length of surgical time, was the only risk factor of pAUR after RALUR-EV.

AB1195 CO-RELATION BETWEEN SELF EFFICACY, DEPRESSION AND PAIN AMONG CAREGIVERS WITH AND WITHOUT ARTHRITIS

Background:

People with arthritis, like others, are often informal caregivers. Caregiving adds burdens of stress and depression. Caregiver studies have shown these to be mitigated by self-efficacy or the confidence to achieve specific caregiving behaviors. Caregivers with arthritis have seldom been studied. We have been unable to find studies specific to caregiving and self-efficacy as they apply to those with and without arthritis. In this study, we evaluated the relationship between self-efficacy, pain, and depression among caregivers with and without arthritis.

Objectives:

1)To examine the correlation between caregiver self-efficacy and depression and pain. 2). To examine how these correlation differ for caregivers with and without arthritis.

Methods:

A caregiver questionnaire was distributed via social media, mainly list serves and blogs to a convenience sample. Those receiving the links were urged to send them to other populations. Respondents self-reported arthritis and weekly hours spent caregiving. They reported pain using a pain (visual numeric scale (1-10)), depression with the Patient Health Questionnaire (PHQ-8), and Self-Efficacy was reported with the short caregiver self-efficacy scale). For caregivers and non-caregivers we compared caregiving hours, pain, depression and self-efficacy. We examined the distribution of caregiving hours by arthritis status and plotted mean pain scores by caregiving hours for caregivers with and without arthritis. The correlation between depression and self-efficacy was measured using Pearson correlation coefficient overall and by arthritis status.

Results:

Over two weeks 155 individuals responded, with data on self-reported arthritis status. Of the respondents, 88% were female and 64% were 50-69 years of age. 46% self-reported arthritis (osteoarthritis was the most common type). Nearly 25% of caregivers reported spending less than 10 hours weekly on caregiving, while approximately 23% reported at the other end of the extreme (at least 40 hours weekly). The distribution by arthritis status of the caregiver is provided in Table 1.

Table 1.Caregiving hoursArthritis0-9 hrs10-19 hrs20-29 hrs30-35 hrs40+ hrsMissingAllNo26 (31%)26 (31%)11 (13%)5 (6%)15 (18%)1 (1%)84 (54.2%)Yes12 (17%)21 (30%)11 (15.5%)7 (9.9%)20 (28%)071 (45.8%)Total38 (24.5%)47 (30.3%)22 (14.2%)12 (7.7%)35 (22.6%)1 (0.7%)155

Caregivers with arthritis reported higher pain in the past week. Mean pain score among caregivers with arthritis was 4.4 (SD 2.2) compared to 2.7 (SD 1.7) among caregivers without arthritis (figure 1). This divergence widened for caregivers with 40 or more hours of caregiving. There was a strong negative correlation (Pearson correlation= – 0.473, p-value <0.0001) between depression and self-efficacy. The correlation was -0.59 for caregivers without arthritis (p=<0.0001, n=74 with data on all three variables) compared to the caregivers self-reporting arthritis (r=-0.35, p=0.006, n=60 with data on all three variables).

Figure 1.

Conclusion:

This study suggests that lower caregiver self-efficacy has a direct and strong association with higher depressive symptoms and that this is more pronounced among caregivers with arthritis. This study also shows that caregivers with arthritis have more pain than caregivers without arthritis, and that this peaks and remains consistent for those doing twenty or more hours of caregiving weekly.. The stronger negative correlation of depression and self-efficacy among patients without arthritis may be explained by other independent contributors (such as pain) to depression in caregivers with arthritis.

References:

[1]Lorig K, Ritter PL, Laurent DD, Yank V. Building Better Caregivers: A Pragmatic 12-Month Trial of a Community-Based Workshop for Caregivers of Cognitively Impaired Adults.J Appl Gerontol. 2019;38(9):1228–1252. doi:10.1177/0733464817741682

Disclosure of Interests:

None declared

Surgical interventions and anesthesia in the 1st year of life for lower urinary tract obstruction

BACKGROUND

Patients with a prenatal diagnosis of lower urinary tract obstruction (LUTO) may undergo prenatal interventions, such as vesicoamniotic shunt (VAS) placement, as a temporary solution for relieving urinary tract obstruction. A recent FDA communication has raised awareness of the potential neurocognitive adverse effects of anesthesia in children. We hypothesized as to whether a prenatal LUTO staging system was predictive of the number of anesthesia events for prenatally diagnosed LUTO patients.

METHODS

We retrospectively reviewed the prenatal and postnatal clinical records for patients with prenatally diagnosed LUTO from 2012 to 2015. Patients were stratified by prenatal VAS status and by LUTO disease severity according to Ruano et al. (Ultrasound Obstet Gynecol. 2016).

RESULTS

31 patients were identified with a prenatal LUTO diagnosis, and postnatal records were available for 21 patients (seven patients in each stage). When combining prenatal and postnatal anesthesia, there was a significant difference in the number of anesthesia encounters by stage (1.6, 3.7, and 6.7 for Stage I, II, and III respectively, p = .034). Upon univariate analysis, higher gestational age (GA) at birth was associated with a decreased number of anesthesia events in the first year (p = .031).

CONCLUSIONS

The majority of infants with prenatally diagnosed LUTO will undergo postnatal procedures with general anesthesia exposure in the first year of life. Patients with higher prenatal LUTO severity experienced a higher number of both prenatal and postnatal anesthesia encounters. In addition, higher GA at birth was associated with fewer anesthesia encounters in the first year.

LEVEL OF EVIDENCE

This is a prognostic study with Level IV evidence.

Efficacy and tolerability of pharmacotherapy options for the treatment of medullary thyroid cancer

Metastatic and unresectable medullary thyroid carcinoma (MTC) is often difficult to treat as it is relatively unresponsive to radiation and conventional chemotherapy. This emphasizes the importance of the development of targeted therapies for advanced MTC. Vandetanib was approved by the US Food and Drug Administration for the treatment of symptomatic or progressive MTC in patients with advanced disease in April 2011. This therapy proved to be a breakthrough in the management of MTC. We review the efficacy and safety of this novel treatment and other treatments that are being evaluated in this disease.

The use of mouse models to investigate shear bond strength in amelogenesis imperfecta

Patients with amelogenesis imperfecta (AI) have defective enamel; therefore, bonded restorations of patients with AI have variable success rates. To distinguish which cases of AI may have good clinical outcomes with bonded materials, we evaluated etching characteristics and bond strength of enamel in mouse models, comparing wild-type (WT) with those having mutations in amelogenin (Amelx) and matrix metalloproteinase-20 (Mmp20), which mimic 2 forms of human AI. Etched enamel surfaces were compared for roughness by scanning electron microscopy (SEM) images. Bonding was compared through shear bond strength (SBS) studies with 2 different systems (etch-and-rinse and self-etch). Etched enamel surfaces of incisors from Amelx knock-out (AmelxKO) mice appeared randomly organized and non-uniform compared with WT. Etching of Mmp20KO surfaces left little enamel, and the etching pattern was indistinguishable from unetched surfaces. SBS results were significantly different when AmelxKO and Mmp20KO enamel surfaces were compared. A significant increase in SBS was measured for all samples when the self-etch system was compared with the etch-and-rinse system. We have developed a novel system for testing shear bond strength of mouse incisors with AI variants, and analysis of these data may have important clinical implications for the treatment of patients with AI.

Rare case of serotonin syndrome with therapeutic doses of paroxetine

Paroxetine (Paxil) is a selective serotonin reuptake inhibitor (SSRI) and anxiolytic that is approved to treat numerous mood disorders. Serotonin syndrome, defined as a triad of mental status changes, autonomic instability, and neuromuscular abnormalities, is a potentially life-threatening complication of administering such serotonin-modifying drugs. Most cases of serotonin syndrome that have occurred with paroxetine administration are due to inadvertent drug interactions, most notably between SSRIs and monamine oxidase inhibitors, or intentional overdoses. The authors present the case of an 80-year-old woman who presented with serotonin syndrome while on a therapeutic dose of paroxetine. Paroxetine was stopped, and aggressive hydration with fluids and treatment with cyproheptadine was followed by remarkable improvement and return to baseline status in 4 days. This case illustrates the importance for physicians to have a heightened sense of suspicion of the serotonin syndrome in any patient known to be on serotonin-modifying agents presenting with altered sensorium and cholinergic symptoms. Consequently, they will be able to start timely treatment without subjecting the patient to unnecessary and potentially harmful tests.

Fluticasone propionate/salmeterol hydrofluoroalkane via metered-dose inhaler with integrated dose counter: Performance and patient satisfaction

Currently, patients have to keep track of doses to determine when to replace their metered-dose inhalers (MDIs). This study evaluated the performance and patient satisfaction of a novel MDI with an integrated dose counter. In an open-label study at 38 outpatient centres, patients > or =12 years old with asthma or chronic obstructive pulmonary disease (COPD) received two actuations of fluticasone propionate/salmeterol 125/25 microg (115/21 microg ex-actuator) hydrofluoroalkane (ADVAIR) HFA) via MDI with counter twice a day until all 120 actuations were completed. Concordance between counter and diary recordings in patients who reported use of > or =90% of labelled actuations (completer population, n = 228) was high (discrepancy rate of 0.94%) and the incidence of device firing without changes in counter readings was low (0.13%). Mean expected actuations based on canister weights (114) were slightly lower than mean counter (121) and diary reported actuations (120). Upon study completion, 95% of patients were satisfied with the dose counter and 92% agreed it would help prevent them from running out of medication. Safety assessments (intent-to-treat population, n = 237) indicated that the drug was well tolerated. This integrated MDI counter may help patients maintain better disease control by enabling them to accurately track their medication supply.

Childhood parental loss and risk for first-onset of major depression and alcohol dependence: the time-decay of risk and sex differences

BACKGROUND

Whereas a number of studies have suggested that parental loss is associated with increased risk for major depression (MD), much less is known about possible gender differences, diagnostic specificity and the time course of the impact of loss.

METHOD

First-onsets for MD and alcohol dependence (AD) were assessed at personal interviews in 5070 twins from same-sex (SS) and 2118 from opposite-sex (OS) twin pairs ascertained from a population-based registry. Cox Proportional Hazard (PH) and Non-Proportional Hazard (NPH) models, examining first onsets of MD and AD, were used with twins from SS pairs and conditional logistic regression for OS pairs. Parent-child separations prior to age 17 were divided into death and separation from other causes.

RESULTS

The PH assumptions of constant increased risk were rejected for the impact of loss on risk for MD but not for AD. NPH models found significantly increased risk for MD after both death and separation with the risk lasting much longer for separations. For AD, the PH model found significantly increased risk after parental separation but not death. In both SS and OS twin pairs, no sex differences were seen in the impact of parental loss on risk for MD whereas the association between separation and risk for AD was significantly stronger in females than in males.

CONCLUSION

Consistent sex differences in the association with parental loss were seen for AD but not MD. The analysis of the time-course of increased risk after loss suggests three different patterns which may reflect different relationships: parental death and MD (return to baseline within approximately 12 years), separation and MD (return to baseline within approximately 30 years) and separation and AD (no change in risk over time).

The liver as an immune organ

Systemic inflammation contributes to significant morbidity in the ICU. With its ability to generate antiinflammatory acute-phase proteins, cytokines via Kupffer cells, and recently acknowledged resident lymphocytes, the liver provides a central regulatory role in inflammation. The liver has constant exposure to foreign material as a result of gut translocation and first-pass metabolism from the bloodstream. Consequently, the balance between hepatic activation and tolerance becomes an important factor in the host response to inflammation. Interventions and therapies that can assess and modulate these hepatic functions can improve outcomes for ICU patients.

Inhibition of p38 mitogen activated protein kinase increases lipopolysaccharide induced inhibition of apoptosis in neutrophils by activating extracellular signal-regulated kinase

BACKGROUND

Prolonged polymorphonuclear neutrophil (PMN) survival has been implicated in tissue injury after sepsis. Previously we reported that lipopolysaccharide (LPS) inhibits PMN apoptosis via the activation of the extracellular signal-regulated kinase (ERK). Conversely, the p38 mitogen activated protein kinase (MAPK) pathway is involved in the spontaneous apoptosis of PMNs. The interaction between these 2 pathways and their ability to regulate apoptosis during sepsis remain largely undefined. We hypothesize that there is interaction between the ERK and p38 pathways during sepsis.

METHODS

PMNs were isolated from healthy volunteers by Ficoll gradient centrifugation and red blood cell sedimentation. Cells were then pretreated for 1 hour with the ERK inhibitor (PD98059, 10 micromol/L), p38 inhibitor (SB203580, 1 micromol/L), or vehicle. After treatment with LPS, apoptosis and MAPK activity were correlated.

RESULTS

LPS stimulation significantly inhibits PMN apoptosis compared with unstimulated cells. Furthermore, inhibition of ERK significantly abrogates this effect, whereas inhibition of p38 augments LPS induced inhibition of apoptosis. Elk-1 phosphorylation (ERK target) is significantly increased by LPS alone and by inhibition of the p38 pathway during LPS stimulation. This correlates with ERK phosphorylation by Western blot.

CONCLUSIONS

These data show that p38 inhibition enhances ERK activity during endotoxemia. Furthermore, these data suggest that cooperation between ERK and p38 MAPK pathways dictates the apoptotic potential of PMNs during inflammatory states.

Heat shock protein 27 inhibits apoptosis in human neutrophils

BACKGROUND

Prolonged neutrophil(PMN) survival has been implicated in tissue injury following sepsis. A variety of bacterial products have been identified which inhibit PMN apoptosis including lipopolysaccharide(LPS). Extracellular heat shock proteins(Hsp) have recently been identified as potent regulatory signals for the innate immune system during the inflammatory response. We hypothesized that Hsp 27 can affect PMN phenotype with respect to apoptosis and cytokine profile.

MATERIALS AND METHODS

PMN were isolated from the peripheral blood of healthy human volunteers by red blood cell sedimentation and gradient centrifugation. Cells were placed in media and cultured for 18 h with and without recombinant human Hsp 27 at various concentrations. In parallel experiments, PMN were stimulated with LPS, a known inhibitor of PMN apoptosis, for comparison. Apoptosis was quantified using annexin V and propidium iodide staining with flow cytometric analysis. Culture supernatants were assayed for secretion of TNF-alpha, IL-10, and IL-12.

RESULTS

Hsp 27 significantly inhibits PMN apoptosis [control; 81.8 +/- 3.6%, vs Hsp 27, 60.4 +/- 4.1% p < 0.05]. The reduction is similar to that signaled by LPS, alone. Together their effect is not synergistic. The Hsp 27 response is dose-dependent. Hsp 27 does not induce secretion of TNF-alpha, IL-10, or IL-12, whereas LPS does signal IL-12 and TNF-alpha secretion.

CONCLUSION

These data demonstrate that exogenous Hsp 27 may play a role in neutrophil-mediated tissue injury during trauma and sepsis via its ability to inhibit neutrophil apoptosis. However, Hsp 27 does not significantly alter neutrophil phenotype with respect to cytokine production profile.

Activated neutrophils induce nitric oxide production in Kupffer cells

Neutrophils (PMN) are proposed to contribute to hepatic dysfunction during sepsis. Transmigrating PMN have been demonstrated to adhere to and injure parenchymal cells (hepatocytes); however, the effect of sepsis-activated PMN on hepatic macrophages or Kupffer cells (KC) is poorly characterized. We hypothesize that PMN influence KC inflammatory mediator production, including nitric oxide. Rodent KC were co-cultured with PMN obtained from controls (Norm-PMN) or endotoxemic rats [lipopolysaccharide (LPS)-PMN] for 18 h. After an 18-h incubation, supernatants and cell lysates of the KC were analyzed for nitric oxide (NO) production. Co-cultures with LPS-PMN/KC demonstrated significantly increased production of nitrite and up-regulation of inducible nitric oxide synthase (iNOS) protein compared to KC alone or Norm-PMN/KC co-cultures. Immunohistochemistry revealed preferential iNOS protein staining in the cytoplasm of KC cultured with LPS-PMN compared to controls. Nitrite production in co-cultures of KC and LPS-PMN where cell contact was inhibited by a cell impermeable but diffusable membrane was significantly reduced. These data provide evidence that KC can be stimulated directly by activated PMN for production of NO. Further, they suggest another mechanism by which PMN modulate hepatic function during sepsis.

Inhibited neutrophil apoptosis: proteasome dependent NF-kappaB translocation is required for TRAF-1 synthesis

Neutrophil (PMN) apoptosis regulates local and systemic inflammation during sepsis. Tumor necrosis factor receptor-associated factors (TRAFs) have been implicated as mediators of apoptosis; however, the signaling pathways for their production in stimulated PMN are unclear. We hypothesize that NF-kappaB translocation is necessary for the induction of TRAF-1 in PMNs with prolonged survival. Neutrophils were isolated from the blood of healthy volunteers by Ficoll gradient centrifugation and red blood cell sedimentation. Neutrophil NF-kappaB was inhibited with a proteasome inhibitor, PSI-I. Cells were treated with PSI-I (30 microM) or vehicle (DMSO 0.2%) for 50 min then incubated over an 18-h time course with LPS (10 to 1000 ng/mL), tumor necrosis factor alpha (TNFalpha) (2 to 20 ng/mL) or control media. In vitro apoptosis was quantified by propidium iodide FACS analysis. Total cellular TRAF-1 was detected by Western blot analysis of cell lysates. Steady state TRAF-1 mRNA was detected by RPA. NF-kappaB activity was determined by Western blot analysis for nuclear p65. Means and standard errors were calculated; data were analyzed by ANOVA. Lipopolysaccharide (LPS) and TNFalpha increased PMN nuclear p65 and steady state TRAF-1 mRNA. Apoptosis was inhibited by TNFalpha and LPS at 12 and 18 h (P < 0.01). Incubation of cells in the NF-kappaB inhibitor PSI-I blocked LPS and TNFalpha-induced inhibition of apoptosis (P < 0.05) and the induction of both nuclear p65 and TRAF-1 mRNA. These data demonstrate that inhibition of PMN apoptosis and TRAF-1 induction by LPS and TNFalpha is NF-kappaB dependent.

Inhibition of alveolar neutrophil immigration in endotoxemia is macrophage inflammatory protein 2 independent

BACKGROUND

Altered transendothelial migration and delayed apoptosis of neutrophils (PMN) have been implicated as contributing to infection in patients with gram-negative sepsis. Macrophage inflammatory protein 2 (MIP-2) signals PMN immigration and may alter other PMN functions. We tested the hypothesis that sequential endotoxin challenge in vivo alters PMN apoptosis and chemotactic responses.

MATERIALS AND METHODS

Endotoxemia was induced in male Wistar rats (250 g) via intraperitoneal (IP) administration of LPS (4 mg/kg). After 18 h, intratracheal (IT) injection of LPS (400 microg/kg) was performed. Control animals received saline injections. Four hours after IT-LPS, circulating and bronchoalveolar lavage (BAL) PMN were isolated. PMN yields were calculated, and apoptosis was quantified after 18 h in culture by annexin V-fluorescein isothiocyanate FACS analysis. BAL MIP-2 concentrations were determined by ELISA. PMN chemotaxis to MIP-2 and IL-8 was determined using a fluorescent in vitro migration assay.

RESULTS

Endotoxemia (IP-LPS) significantly decreases BAL PMN yield in response to an in vivo IT-LPS challenge. IT-LPS inhibits BAL PMN apoptosis to the same extent as sequential IP/IT-LPS. Alveolar MIP-2 concentrations are similar in the two groups. In vitro migration to IL-8 and MIP-2 was inhibited in PMN from endotoxemic versus control animals.

CONCLUSIONS

These data demonstrate that endotoxemia inhibits PMN migration despite similar MIP-2 concentrations in the alveolus. Sequential insults do not affect the inhibition of apoptosis. In vitro, PMN from endotoxemic animals display impaired chemotaxis to MIP-2 and interleukin-8. This may result in an inadequate host defense that contributes to increased ICU-acquired pneumonia in septic patients.

Admission serum magnesium level does not predict the hospital outcome of patients with acute myocardial infarction

OBJECTIVE

To establish whether hypomagnesemia at admission predicts excessive morbidity, particularly cardiac arrhythmias, and mortality in patients with acute myocardial infarction.

METHODS

We compared hypomagnesemic and normomagnesemic patients with acute myocardial infarction in 517 patients admitted to the coronary care unit. The serum magnesium concentration, along with a large array of other parameters, was measured on admission to the emergency department. Other baseline attributes and variables related to the patients' hospital course were used to compare the 2 groups.

RESULTS

The 132 patients (25.9%) with low serum magnesium concentrations at admission (mean +/- SD, 0.61 +/- 0.06 mmol/L [1.48 +/- 0.15 mg/dL]) were comparable to the patients with normal serum magnesium concentrations (0.81 +/- 0.11 mmol/L [1.96 +/- 0.26 mg/dL]) except for a higher rate of prehospital use of diuretic agents (32.6% vs 22.5%, P = .02) and earlier presentation after onset of symptoms (mean +/- SD, 3.2 +/- 4.1 vs 4.8 +/- 6.6 hours, P = .003). There was no correlation between serum magnesium and potassium concentrations in the emergency department (r = 0.14). No difference was detected between the hypomagnesemic and normomagnesemic cohorts in rates of total mortality (18.9% vs 18.5%, P = .91), cardiac mortality (15.2% vs 15.3%, P = .99), atrial fibrillation (13.6% vs 13.8%, P = .97), ventricular tachycardia (18.2% vs 15.3%, P = .44), or ventricular fibrillation (15.2% vs 13.5%, P = .63). Management of the 2 cohorts was not different, except for higher rates of use of magnesium (17.4% vs 1.3%, P < .001) and potassium (59.8% vs 42.1%, P < .001) supplements and antiarrhythmic drugs (62.9% vs 48.7%, P = .005) in the hypomagnesemic patients. An endogenous rise in serum magnesium level was documented in a subgroup of 161 patients who had a repeated measurement (0.74 +/- 0.12 mmol/L [1.79 +/- 0.29 mg/dL] in the emergency department vs 0.77 +/- 0.09 mmol/L [1.88 +/- 0.23 mg/dL] in the coronary care unit, P < .001).

CONCLUSIONS

We conclude that hypomagnesemia is seen in approximately one fourth of patients with myocardial infarction, is not linked to hypokalemia, has some relationship to preadmission use of diuretic agents, is associated with early presentation to the hospital, and is not a predictor of increased morbidity or mortality.

Expression of quinone reductase activity in embryonal and adult porcine tissues

Quinone reductase (QR; EC 1.6.99.2) is recognized as a major antimutagenic/anticarcinogenic enzyme in the organism. Our recent studies demonstrated the presence of significant QR activity in the early human placenta; whether this enzyme is expressed by the mammalian embryo is not known at present. In the investigation reported here, we sought to determine whether or not QR activity is detected in porcine embryonal tissues and if so, how early this expression takes place. In addition, the enzyme activity in the embryo was compared to that present in adult porcine tissue. Enzyme activity was determined by a colorimetric method with menadione as substrate in the presence of tetrazolium salt (MTT). NADH was a preferable cofactor in the embryo, whereas in the adult tissues NADPH was a better cofactor. Results show that the enzyme is present in all the embryonal organs tested from a very early age (30 days of gestation). Among the organs tested, activity was highest in the porcine embryo liver, and the specific activity remained unchanged until Day 70. Activity in the embryonal kidney increased with advancing gestation. The enzyme activity in embryonal tissues was much lower than that measured in the adult liver (30-40-fold). These findings suggest that the embryo has the potential for inactivating carcinogens/mutagens that will subsequently be eliminated by the maternal organism, thus protecting against adverse environmental impacts during the most critical period of development.

Predictive power of sperm motion analysis in in vitro fertilization

The correlation between sperm motion characteristics and in vitro fertilization was studied in 160 cycles, divided in two groups: those with male subfertility (N=42) and those with tubal disease (N=118). The group with male subfertility showed inferior performance, as indicated by a lower fertilization rate per oocyte (40% versus 66%) and per pick-up cycle (67% versus 93%). These two groups exhibited no significant difference in the mean sperm velocity, linearity, amplitude of lateral head displacement, and beat cross frequency in the pre swim-up and post swim-up specimens. The two groups differed in pre and post swim-up sperm motility, pre and post swim-up concentration, pre swim-up cumulative velocity at 110 to 140 Amicrom/sec and post swim-up cumulative velocity at 130 microm/sec. Logistic regression analysis was used to determine those variables that would predict fertilization; pre swim-up count and post swim-up motility proved to be the significant determinants. The results indicate that assessment of motion by automated semen analyzers does not supplement conventional semen analysis in the ability to predict fertilization.

Zyn-Linker delivery of antirheumatic agents

Despite our increasing ability to manage rheumatoid arthritis through systemic medication, refractory joints require local administration of more aggressive therapy in a substantial number of patients. These studies tested whether a new class of molecules designated Zyn-Linkers could deliver and retain therapeutics in a joint. Zyn-Linkers are synthetic lipid-like molecules designed to insert into cell membranes and enhance drug delivery to cells. After intra-articular injection into the knee of NZW rabbits, Zyn-Linkers bound rapidly and homogenously to synovial lining cells. Chelating Zyn-Linkers which contained Re-186 or Y-90 were synthesized to evaluate localization and retention after intra-articular injection. Initial studies using Re-186 Zyn-Linker gave excellent localization as evaluated by whole-body imaging: counts in the knee region represented > 90% of counts present in the whole body for at least 4-6 days postinjection. Similar results were obtained using a Y-90 Zyn-Linker and this agent was used for biodistribution studies due to its greater stability and ease of preparation. Efficacy and safety of Y-90 Zyn-Linker as a potential radiation synovectomy agent were estimated by extrapolation of biodistribution data to humans. A therapeutically effective dose of 8,000 cGy to synovium was calculated to require intra-articular injection of 3.4 mCi Y-90 Zyn-Linker, a value less than or equal to doses of particulate Y-90 agents used clinically in Europe. The predicted safety profile for Y-90 Zyn-Linker was excellent, with estimated doses to nontarget organs and tissues falling well within FDA-recommended safety levels for research-only radiopharmaceuticals. In addition to exhibiting desirable localization and retention properties, Zyn-Linkers may also be synthesized to release antirheumatic drugs such as methotrexate at controlled rates. This suggests substantial potential for these drug delivery molecules as chemical synovectomy agents which may be used concurrently with systemic chemotherapy to improve management of refractory joints.

Kidney transplantations at King Faisal Specialist Hospital and Research Centre

During the five year period from 1987G to 1991G, 161 kidney transplantations were performed at King Faisal Specialist Hospital and Research Centre (KFSH&RC); 79 from cadaveric donors (CD) and 82 from living related donors (LRD). All cadaveric kidneys except one were harvested within Saudi Arabia and 67% were from Saudi nationals. The immunosuppresive protocol was a triple drug regimen comprising cyclosporin-A (CyA), azathioprine (Aza), and prednisone. The actuarial graft survival rates at one and three years were 85% and 76% for the cadaveric donor transplants and 96% and 91%, respectively for the living related donor transplants (P<0.01). The corresponding patient survival rates for cadaveric donor transplants (CDTxs) were 97% and 94% and for the living related donor transplants (LRDTxs), 99% and 97% (NS). These results compare well with the best results in the Western world. The most serious surgical complications were vascular thromboses (five cases) and infections of the arterial anastomosis line with bleeding (two cases), all leading to loss of the cadaveric graft. The most common causes of death were virus infection, varicella, cytomegalovirus, and hepatitis B and C. The organ donation rate, from cadaveric donors as well as living related donors, is stil low in Saudi Arabia. Lack of organs is the main obstacle to an expansion of this promising transplantation activity. Continuous education of the multinational medical profession as well as the lay population is necessary to improve the situation.

Inhibition of neutrophil functions by human immunoglobulin E

Incubation of human neutrophils with human immunoglobulin (Ig) E caused dose-dependent inhibition of adhesion, phagocytosis, secretion of myeloperoxidase, and oxygen radical production. The concentrations of IgE that caused 50% inhibition of adhesion, phagocytosis, and secretion were 2 +/- 0.3, 2.16 +/- 0.21, and 1.95 +/- 0.28 ng/ml, respectively. Oxidase activation as measured by luminol-dependent chemiluminescence by the receptor-mediated N-formyl-methionyl-leucyl-phenylalanine, phorbol 12-myristate 13-acetate, or the particulate stimulus Staphylococcus aureus was inhibited by IgE with concentrations causing 50% effect of 1.2 +/- 0.13, 1.09 +/- 0.16, and 0.6 +/- 0.09 ng/ml, respectively. IgE also inhibited oxygen consumption rate and cytochrome c reduction with similar K0.5 values. The effect of IgE was unlikely to be due to nonspecific cytotoxicity because trypan blue exclusion test and the cytoplasmic marker lactate dehydrogenase revealed that the cells retained their viability after IgE treatment. Similar or higher concentrations of IgG invoked either no inhibition or a slight enhancement of neutrophil functions. Pretreatment of neutrophils with IgG failed to affect the IgE-induced inhibition. Because the effect of IgE occurs at concentrations less than those reported in hyperimmunoglobulinemia E, we propose that direct inhibition of neutrophil functions may underlie the pathogenesis of recurrent infection associated with hyperimmunoglobulinemia E.

Riyadh chromosome breakage syndrome: mental retardation with depigmentation of the skin and hair

A 20-month-old infant with "silvery-blond" hair color, widespread confettilike depigmentation of the skin, and mental retardation was found to have, in lymphocytes and fibroblast cultures, increased spontaneous chromosome breaks and breaks induced by both mitomycin and gamma-irradiation. The sister chromatid exchange frequency was normal. This child probably represents a new chromosome breakage syndrome.

Immunosuppression by human seminal plasma fractionated by DEAE Sephadex A-50 ion exchange chromatography

We fractionated the whole human seminal plasma on DEAE Sephadex A-50 ion exchange columns. Complete separation was achieved in seven peaks using different salt concentrations in phosphate buffer pH 6. The seminal plasma proteins were separated by sodium dodecyl-sulphate polyacrylamide gel electrophoresis. Human seminal plasma (SP) and its fractions were used in mixed lymphocyte reaction in vitro. Fractions 3, 4, and 7 were found to suppress the proliferation of human peripheral blood mononuclear cells to phytohemagglutinin and pokweed mitogen at a concentration of 10 micrograms ml-1 while stimulatory effect was observed at lower concentrations (1 microgram and 2.5 micrograms ml-1). Whole human SP and other fractions failed to suppress the proliferation of lymphocytes in vitro. Furthermore, the effect of human SP and its fractions was also investigated on phagocytic function of polymorphonuclear leukocytes (PMNs) using luminol dependent chemiluminescence assay stimulated with phorbol myristate acetate and opsonized yeast. Fractionated SP was found to have a suppressive effect on the luminol-dependent chemiluminescence of PMNs in the whole blood.

Factors predictive of post-transplant erythrocytosis

Ninety-three patients with PTE (that is, hematocrit 51% or greater) were identified among 431 renal transplant recipients, an incidence of 21.6%. Thirty-eight patients underwent blood volume measurements, and 22 of these had high red cell volume and therefore were considered to have true PTE. To analyze factors predictive of erythrocytosis, a control group with normal hematocrit was randomly selected from our renal transplant population and compared with the 93 patients with PTE, and with the 22 who had true PTE. Using step-wise logistic regression analysis, we identified three variables that were consistent predictors of PTE. In order of significance, the serum creatinine value at the onset of PTE appears to most strongly predict the occurrence of PTE (P less than 0.0001). As creatinine value increases, the probability of PTE decreases. Next was immunosuppression, where double immunosuppressive therapy was associated with a greater probability of PTE than triple therapy (P less than 0.0001). The overall incidence of PTE in patients on double therapy was 34%, while that for those on triple therapy 10.4%. Last was duration of dialysis for which increasing values correspond to increasing probability of PTE (P = 0.004). Comparison of the serum erythropoietin (EPO) levels for patients and controls yielded a nonsignificant result (P = 0.2507 and P = 0.383 for all patients with PTE and true PTE, respectively), and therefore EPO levels were inappropriately elevated for the level of hematocrit in the PTE group. Only the number of rejections and duration of follow-up (r = -0.3507) were significantly correlated with EPO (P less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Endotoxemia and release of tumor necrosis factor and interleukin 1 alpha in acute heatstroke

To determine whether endotoxemia and release of tumor necrosis factor (TNF-alpha) and/or interleukin 1 alpha (IL-1 alpha) are involved in the pathogenesis of heatstroke, 17 adult patients with a mean rectal temperature of 42.1 +/- 0.2 degrees C were studied. Blood samples were taken on admission and after cooling was completed. TNF-alpha and IL-1 alpha levels were measured by enzyme-linked immunosorbent assay, and lipopolysaccharide (LPS) content was measured by the chromogenic substrate modification of the Limulus amebocyte lysate. TNF-alpha, IL-1 alpha, and LPS were elevated in all patients [199 +/- 25 (SE) pg/ml, 480.5 +/- 68.3 pg/ml, and 8.60 +/- 1.19 ng/ml, respectively, compared with normal control values of 31.4 +/- 8.4 pg/ml, 53.7 +/- 5.32 pg/ml, and less than 9 pg/ml]. There was no significant correlation between temperature and the circulating concentration of TNF-alpha, IL-1 alpha, and LPS. Postcooling TNF-alpha, IL-1 alpha, and LPS concentrations were significantly decreased but still above normal control values. The findings suggest that these mediators may have a role in the pathogenesis of heatstroke that could change the strategy of management.

Frequency of HLA genes and islet cell antibodies (ICA) and result of postpartum oral glucose tolerance tests (OGTT) in Saudi Arabian women with abnormal OGTT during pregnancy

A consecutive series of 55 Saudi women with abnormal 75 g oral glucose tolerance test (OGTT) during pregnancy was reinvestigated 2-4 months after delivery. A 75 g OGTT was done and samples were also drawn for analysis of C-peptide concentration, islet cells antibodies (ICA) and HLA antigens. The results of these laboratory investigations and a number of patient characteristics were analyzed to identify risk factors for patients likely to have impaired OGTT after delivery. Twenty-five (45.5%) of the patients had an abnormal OGTT after delivery. The distribution of HLA antigen frequencies did not differ from a reference group of healthy Saudis. ICA were found in only one patient. Logistic regression analysis identified insulin treatment during pregnancy (p = 0.001) as the only factor to predict an abnormal OGTT after delivery.