Predictors of adverse outcomes in elders hospitalised for isolated orthopaedic trauma: a multicentre cohort study

BACKGROUND

Patients >64 years of age now represent more than 51% of injury hospitalisations in Canada. The tools used to identify older patients who could benefit the most from an interdisciplinary approach include complex parameters difficult to collect in the ED, which suggests that better tools with higher accuracy and using items that can be derived from routinely collected data are needed. We aimed to identify variables that are associated with adverse outcomes in older patients admitted to a trauma centre for an isolated orthopaedic injury.

METHODS

We conducted a multicentre retrospective cohort study between 1 April 2013 and 31 March 2019 on older patients hospitalised with a primary diagnosis of isolated orthopaedic injury (n=19 928). Data were extracted from the provincial trauma registry (Registre des traumatismes du Québec). We used multilevel logistic regression to estimate the associations between potential predictors and adverse outcomes (extended length of stay, mortality, complications, unplanned readmission and adverse discharge destination).

RESULTS

Increasing age, male sex, specific comorbidities, type of orthopaedic injuries, increasing number of comorbidities, severe orthopaedic injury, head injuries and admission in the year before the injury were all significant predictors of adverse outcomes.

CONCLUSION

We identified eight predictors of adverse outcomes in patients >64 years of age admitted to a trauma centre for orthopaedic injury. These variables could eventually be used to develop a clinical decision rule to identify elders who may benefit the most from interdisciplinary care.

Identifying Quality Indicators for the Care of Hospitalized Injured Older Adults: A Scoping Review of the Literature

OBJECTIVES

Older adults represent more than 50% of trauma admissions in many high-income countries. Furthermore, they are at increased risk for complications, resulting in worse health outcomes than younger adults and a significant health care utilization burden. Quality indicators (QIs) are used to assess the quality of care in trauma systems, but few QIs reflect responses to older patients' specific needs. We aimed to (1) identify QIs used to assess acute hospital care for injured older patients, (2) assess support for identified QIs and, (3) identify gaps in existing QIs.

DESIGN

Scoping review of the scientific and gray literature.

METHODS

Selection and data extraction were performed by 2 independent reviewers. The level of support was assessed by the number of sources reporting QIs and whether they were developed according to scientific evidence, expert consensus, and patients' perspectives.

RESULTS

Of 10,855 identified studies, 167 were eligible. Among 257 different QIs identified, 52% were hip fracture specific. Gaps were identified for head injuries, rib, and pelvic ring fractures. Although 61% of QIs assessed care processes, 21% and 18% focused on structures and outcomes, respectively. Although most QIs were based on literature reviews and/or expert consensus, patients' perspective was rarely accounted for. The 15 QIs with the highest level of support included minimum time between emergency department arrival and ward admission, minimum time to surgery for fractures, assessment by a geriatrician, orthogeriatric review for hip fracture patients, delirium screening, prompt and appropriate analgesia, early mobilizations, and physiotherapy.

CONCLUSION AND IMPLICATIONS

Multiple QIs were identified, but their level of support was limited, and important gaps were identified. Future work should focus on achieving consensus for a set of QIs to assess the quality of trauma care to older adults. Such QIs could be used for quality improvement and ultimately improve outcomes for injured older adults.

Amyloid and APOE Status of Screened Subjects in the Elenbecestat MissionAD Phase 3 Program

BACKGROUND/OBJECTIVES

Elenbecestat, an oral BACE-1 inhibitor that has been shown to reduce Aβ levels in cerebrospinal fluid, was investigated in two global phase 3 studies in early AD. Here we report on differences observed in characteristics of APOE ε4 and amyloid positive subjects in the large screening cohort.

DESIGN

Screening was performed in 5 sequential tiers over a maximum of 80 days, as part of placebo controlled, double blind phase 3 studies.

SETTING

Subjects were evaluated at sites in 7 regions (29 countries).

PARTICIPANTS

Overall, 9758 subjects were screened.

INTERVENTION

All screened subjects that were eligible received either placebo or 50 mg QID elenbecestat post randomisation.

MEASUREMENTS

Gender, disease staging, APOE ε4 status, amyloid status, amyloid positron emission tomography (PET) standard uptake value ratio (SUVr) and amyloid PET Centiloid (CL) values were determined for screened subjects; by country and region.

RESULTS

In this program, 44% of subjects were APOE ε4 positive. Frequency of females was similar in both APOE ε4 positive and negative groups. However, early mild AD subjects were slightly higher in the APOE ε4 positive group compared with the APOE ε4 negative group. 56% of subjects were amyloid positive. The mean age in the amyloid positive group was slightly higher than the amyloid negative group. The gender distribution was similar between amyloid groups. A lower number of mild cognitive impairment was observed in the amyloid positive group along with a higher number of early mild AD. APOE ε4 positive subjects were higher in amyloid positive group compared to the amyloid negative group. China had the lowest APOE ε4 and amyloid positivity rates with Western Europe and Oceania performing best. Subjects received florbetapir, florbetaben or flutemetamol amyloid PET tracer. Amyloid negative and positive subjects CL values were normally distributed around their respective means of 1.5 CL and 83 CL. However, there was an appreciable overlap in the 20-40 CL range.

CONCLUSIONS

In this large cohort of cognitively impaired subjects, subject demographics characteristics were comparable regardless of APOE genotype or amyloid positivity. APOE ε4 positivity and amyloid positivity varied by country and by geographical region.

Functional and cognitive decline in older delirious adults after an emergency department visit

BACKGROUND

the aim of this study was to evaluate the impact of emergency department (ED) stay-associated delirium on older patient's functional and cognitive status at 60 days post ED visit.

METHODS

this study was part of the multi-centre prospective cohort INDEED study. This project took place between March 2015 and July 2016 in five participating EDs across the province of Quebec. Independent non-delirious patients aged ≥65, with an ED stay ≥8 hours, were monitored for delirium until 24 hours post ward admission. A 60-day follow-up phone assessment was conducted. Participants were screened for delirium using the Confusion Assessment Method. Functional and cognitive statuses were assessed at baseline and at the 60-day follow-up using OARS and TICS-m.

RESULTS

a total of 608 patients were recruited, 393 of which completed the 60-day follow-up. The Confusion Assessment Method was positive in 69 patients (11.8%) during ED stay or within the first 24 hours following ward admission. At 60 days, delirium patients experienced an adjusted loss of -2.9/28 [95%CI: -3.9, -2.0] points on the OARS scale compared to non-delirious patients who lost -1.6 [95%CI: -1.9, -1.3] (P = 0.006). A significant adjusted difference in cognitive function was also noted at 60 days, as TICS-m scores in delirious patients decreased by -1.6 [95%CI: -3.5, 0.2] compared to non-delirious patients, who showed a minor improvement of 0.5 [95%CI: -0.1, 1.1] (P = 0.03).

CONCLUSION

seniors who developed ED stay-associated delirium have lower baseline functional and cognitive status than non-delirious patients, and they will experience a more significant decline at 60 days post ED visit.

Blood CD9+ B cell, a biomarker of bronchiolitis obliterans syndrome after lung transplantation

Bronchiolitis obliterans syndrome is the main limitation for long-term survival after lung transplantation. Some specific B cell populations are associated with long-term graft acceptance. We aimed to monitor the B cell profile during early development of bronchiolitis obliterans syndrome after lung transplantation. The B cell longitudinal profile was analyzed in peripheral blood mononuclear cells from patients with bronchiolitis obliterans syndrome and patients who remained stable over 3 years of follow-up. CD24^hi CD38^hi transitional B cells were increased in stable patients only, and reached a peak 24 months after transplantation, whereas they remained unchanged in patients who developed a bronchiolitis obliterans syndrome. These CD24^hi CD38^hi transitional B cells specifically secrete IL-10 and express CD9. Thus, patients with a total CD9⁺ B cell frequency below 6.6% displayed significantly higher incidence of bronchiolitis obliterans syndrome (AUC = 0.836, PPV = 0.75, NPV = 1). These data are the first to associate IL-10-secreting CD24^hi CD38^hi transitional B cells expressing CD9 with better allograft outcome in lung transplant recipients. CD9-expressing B cells appear as a contributor to a favorable environment essential for the maintenance of long-term stable graft function and as a new predictive biomarker of bronchiolitis obliterans syndrome-free survival.

Effects of Chlorpyrifos on Cholinesterase and Serine Lipase Activities and Lipid Metabolism in Brains of Rainbow Trout (Oncorhynchus mykiss)

Chlorpyrifos is an organophosphorus insecticide that elicits acute toxicity through inhibition of acetylcholinesterase (AChE), leading to acetylcholine accumulation and prolonged stimulation of cholinergic receptors throughout the central and peripheral nervous systems. Previous studies have indicated that neurodevelopment may also be impaired through alternative pathways, including reduction of cAMP catalyzed downstream events. The upstream initiating events that underlie non-cholinergic neurological actions of chlorpyrifos and other organophosphorus compounds remain unclear. To investigate the potential role of disruption of fatty acid signaling as a mechanism of toxicity, lipid metabolism and fatty acid profiles were examined to identify alterations that may play a critical role in upstream signaling in the CNS. Juvenile rainbow trout were treated for 7 days with nominal chlorpyrifos concentrations previously reported to diminish olfactory responses (10, 20, and 40 μg/L). While lethality was noted higher doses, measured chlorpyrifos concentrations of 1.38 μg/L (nominal concentration 10 μg/L) significantly reduced the activity of AChE and two serine lipases, monoacylglycerol lipase and fatty acid amide hydrolase in the brain. Reductions in lysophosphatidylethanolamines (16:0; 18:0, 18:1, and 22:6) derived from the phosphatidylethanolamines and free fatty acids (Palmitic acid16:0; Linolenic acid18:3; Eicosadienoic acid 20:2; Arachidonic acid 20:4; and Docosahexaenoic acid 22:6) were also noted, suggesting that chlorpyrifos inhibited the metabolism of selected phospholipid signaling precursors at sublethal concentrations. These results indicate that in addition to AChE inhibition, environmentally relevant chlorpyrifos exposure alters serine lipase activity and lipid metabolites in the trout brain, which may compromise neuronal signaling and impact neurobehavioral responses in aquatic animals.

Is the Drug Burden Index Related to Declining Functional Status at Follow-up in Community-Dwelling Seniors Consulting for Minor Injuries? Results from the Canadian Emergency Team Initiative Cohort Study

BACKGROUND

The Canadian Emergency Team Initiative (CETI) cohort showed that minor injuries like sprained ankles or small fractures trigger a downward spiral of functional decline in 16% of independent seniors up to 6 months post-injury. Such seniors frequently receive medications with sedative or anticholinergic properties. The Drug Burden Index (DBI), which summarises the drug burden of these specific medications, has been associated with decreased physical and cognitive functioning in previous research.

OBJECTIVES

We aimed to assess the contribution of the DBI to functional decline in the CETI cohort.

METHODS

CETI participants were assessed physically and cognitively at baseline during their consultations at emergency departments (EDs) for their injuries and up to 6 months thereafter. The medication data were used to calculate baseline DBI and functional status was measured with the Older Americans Resources and Services (OARS) scale. Multivariate linear regression models assessed the association between baseline DBI and functional status at 6 months, adjusting for age, sex, baseline OARS, frailty level, comorbidity count, and mild cognitive impairment.

RESULTS

The mean age of the 846 participants was 77 years and their mean DBI at baseline was 0.24. Complete follow-up data at 3 or 6 months was available for 718 participants among whom a higher DBI at the time of injury contributed to a lower functional status at 6 months. Each additional point in the DBI lead to a loss of 0.5 points on the OARS functional scale, p < 0.001. Among those with a DBI ≥ 1, 27.4% were considered 'patients who decline' at 3 or 6 months' follow-up, compared with 16.0% of those with a DBI of 0 (p = 0.06).

CONCLUSIONS

ED visits are considered missed opportunities for optimal care interventions in seniors; Identifying their DBI and adjusting treatment accordingly may help limit functional decline in those at risk after minor injury.

Cryptic amyloidogenic elements in mutant NEFH causing Charcot-Marie-Tooth 2 trigger aggresome formation and neuronal death

Neurofilament heavy chain (NEFH) gene was recently identified to cause autosomal dominant axonal Charcot-Marie-Tooth disease (CMT2cc). However, the clinical spectrum of this condition and the physio-pathological pathway remain to be delineated. We report 12 patients from two French families with axonal dominantly inherited form of CMT caused by two new mutations in the NEFH gene. A remarkable feature was the early involvement of proximal muscles of the lower limbs associated with pyramidal signs in some patients. Nerve conduction velocity studies indicated a predominantly motor axonal neuropathy. Unique deletions of two nucleotides causing frameshifts near the end of the NEFH coding sequence were identified: in family 1, c.3008_3009del (p.Lys1003Argfs*59), and in family 2 c.3043_3044del (p.Lys1015Glyfs*47). Both frameshifts lead to 40 additional amino acids translation encoding a cryptic amyloidogenic element. Consistently, we show that these mutations cause protein aggregation which are recognised by the autophagic pathway in motoneurons and triggered caspase 3 activation leading to apoptosis in neuroblastoma cells. Using electroporation of chick embryo spinal cord, we confirm that NEFH mutants form aggregates in vivo and trigger apoptosis of spinal cord neurons. Thus, our results provide a physiological explanation for the overlap between CMT and amyotrophic lateral sclerosis (ALS) clinical features in affected patients.

The impact of a standardized order set for the management of non-hip fragility fractures in a Fracture Liaison Service

We analysed the impact of a standardized order set empowering staff nurses to independently manage a Fracture Liaison Service over a 9-month period. Nurses identified between 30 and 70 % of non-hip fragility fractures to the unit in charge of management over time. The latter managed 58 % of referred patients.

INTRODUCTION

The main goal of this study was to evaluate the impact of a standardized order set empowering nurses to independently manage a fracture liaison service (FLS).

METHODS

Since November 2014, an order set allowed nurses of a Montreal hospital, Quebec, Canada to entirely manage an FLS on their own. Nurses followed an 6-h training program on-site. Emergency department (ED) and orthopaedic outpatient clinic (OC) nurses identified non-hip fragility fractures. Medical day treatment unit (MDTU) nurses were in charge of the management (investigation and treatment initiation). The list of patients, 50 years and older, with a fracture were retrieved for the period of November 2014 to July 2015. Performance was assessed with the rate of identification over time and the rate of management of non-hip fragility fractures.

RESULTS

Over the 9-month period, 346 patients of ≥50 years old were seen for a fracture, of which 190 met fragility criteria (excluding hip fractures). A sinusoid pattern of rates of identification between 30-70 % was observed over time. An average proportion of 58.1 % of fracture patients were managed by MDTU nurses.

CONCLUSIONS

A standardized order set legally allowing nurses to manage an FLS led to identification rates varying from 30-70 % and a management rate close to 60 % for referred patients over a 9-month period, which largely exceeds that of standard care. Identification was mostly compromised by difficulty integrating the order set into routine practice. Enforcement of the hospital policy on fragility fractures could help yield efficiency of identification of osteoporosis-related fractures by the staff.

High-affinity σ1 protein agonist reduces clinical and pathological signs of experimental autoimmune encephalomyelitis

BACKGROUND AND PURPOSE

Selective agonists of the sigma-1 receptor (σ1 protein) are generally reported to protect against neuronal damage and modulate oligodendrocyte differentiation. Human and rodent lymphocytes possess saturable, high-affinity binding sites for compounds binding to the σ1 protein and potential immunomodulatory properties have been described for σ1 protein ligands. Experimental autoimmune encephalomyelitis (EAE) is recognized as a valuable model of the inflammatory aspects of multiple sclerosis (MS). Here, we have assessed the role of a σ1 protein agonist, containing the tetrahydroisoquinoline-hydantoin structure, in EAE.

EXPERIMENTAL APPROACH

EAE was induced in SJL/J female mice by active immunization with myelin proteolipid protein (PLP)139-151 peptide. The σ1 protein agonist was injected i.p. at the time of immunization (day 0). Disease severity was assessed clinically and by histopathological evaluation of the CNS. Phenotyping of B-cell subsets and regulatory T-cells were performed by flow cytometry in spleen and cervical lymph nodes.

KEY RESULTS

Prophylactic treatment of EAE mice with the σ1 protein agonist prevented mononuclear cell accumulation and demyelination in brain and spinal cord and increased T2 B-cells and regulatory T-cells, resulting in an overall reduction in the clinical progression of EAE.

CONCLUSIONS AND IMPLICATIONS

This σ1 protein agonist, containing the tetrahydroisoquinoline-hydantoin structure, decreased the magnitude of inflammation in EAE. This effect was associated with increased proportions of B-cell subsets and regulatory T-cells with potential immunoregulatory functions. Targeting of the σ1 protein might thus provide new therapeutic opportunities in MS.

Extensive myelitis associated with anti-NMDA receptor antibodies

Background

Encephalitis with anti-N-methyl-D-aspartate receptor antibodies (anti-NMDAR-Ab) is a rapid-onset encephalitis including psychosis, seizures, various movement disorders and autonomic system disturbances.

Case presentation

We report a very unusual case of extensive myelitis associated with anti-NMDAR-Ab. MRI also revealed a hyperintense T2 lesion, non-suggestive of MS, which progressively extended, associated with periventricular gadolinium enhancement visualized on brain MRI. Ophthalmological evaluation showed subclinical right optic neuritis. The absence of anti-AQP4 antibody argued against neuromyelitis optica spectrum disorder. A slight psychomotor slowing prompted us to search for various causes of autoimmune encephalitis. Anti-NMDAR-Ab was found in cerebrospinal fluid.

Conclusion

In patients with extensive myelitis who are seronegative for anti-AQP4 antibodies, and after other classical causes have been excluded, the hypothesis of atypical anti-NMDAR-Ab encephalitis should also be considered.

JC-virus seroconversion in multiple sclerosis patients receiving natalizumab

AIM

The objectives of this study were to evaluate the rate of JC virus (JCV) seroconversion/seroreversion in a French cohort of multiple sclerosis (MS) patients receiving natalizumab (NTZ), describe the characteristics of this population, identify risk factors for JCV seropositivity and analyse the additional value of quantitative JCV serology results in this context.

METHODS

MS patients from two French MS centres, whose JCV serological status in 2011 while receiving NTZ was known (n=357; first-generation enzyme-linked immunosorbent assay (ELISA) test (Gen1)), were proposed for inclusion in this study. We evaluated the rate of JCV seroconversion over a period of one year with a second-generation ELISA test (Gen2; n=303) and analysed the quantitative results. Multivariate analysis was performed to identify risk factors for JCV seropositivity.

RESULTS

Among the patients with Gen2 JCV serology (n=303) that had been JCV-seronegative one year before (n=165), the rate of JCV seroconversion was 26.67% (44/165). We observed a higher proportion of anti-JCV antibody seroconverters (14.5%) than expected (≤3%) but also increasing index values of anti-JCV antibody over time.

CONCLUSION

Our data suggest that JCV reactivation occurs during NTZ therapy and leads to an increase in the anti-JCV antibodies titre, thus making them more easily detectable by the second-generation ELISA test.

The TGF-β-Smad3 pathway inhibits CD28-dependent cell growth and proliferation of CD4 T cells

Transforming growth factor-β (TGF-β) maintains self-tolerance through a constitutive inhibitory effect on T-cell reactivity. In most physiological situations, the tolerogenic effects of TGF-β depend on the canonical signaling molecule Smad3. To characterize how TGF-β/Smad3 signaling contributes to maintenance of T-cell tolerance, we characterized the transcriptional landscape downstream of TGF-β/Smad3 signaling in resting or activated CD4 T cells. We report that in the presence of TGF-β, Smad3 modulates the expression of >400 transcripts. Notably, we identified 40 transcripts whose expression showed Smad3 dependence in both resting and activated cells. This 'signature' confirmed the non-redundant role of Smad3 in TGF-β biology and identified both known and putative immunoregulatory genes. Moreover, we provide genomic and functional evidence that the TGF-β/Smad3 pathway regulates T-cell activation and metabolism. In particular, we show that TGF-β/Smad3 signaling dampens the effect of CD28 stimulation on T-cell growth and proliferation. The impact of TGF-β/Smad3 signals on T-cell activation was similar to that of the mTOR inhibitor Rapamycin. Considering the importance of co-stimulation on the outcome of T-cell activation, we propose that TGF-β-Smad3 signaling may maintain T-cell tolerance by suppressing co-stimulation-dependent mobilization of anabolic pathways.

Pegylated liposomal doxorubicin (PLD) with cyclophosphamide (C) as 1st-line chemotherapy for metastatic breast cancer (MBC) patients previously treated with adjuvant anthracyclines

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Background: Anthracyclines (A) are key elements in adjuvant and metastatic chemotherapy regimens for breast cancer. Pre-exposure limits the utilization of A in advanced disease due to cumulative cardiotoxicity. PLD (Caelyx/Doxil) has equivalent activity to conventional doxorubicin in MBC. However PLD has reduced toxicity, including significantly less cardiotoxicity. Combinations of A+C are the backbone of many adjuvant therapies, thus C represents a logical drug to combine with PLD. Methods: MBC patients with measurable disease who completed anthracycline containing adjuvant therapy > 12 months ago were entered in a multi-center single arm phase II trial. They received PLD 35mg/m2 + cyclophosphamide 600 mg/m2 every 3 weeks. This study was powered to demonstrate an objective response rate > 25%. Results: Seventy three patients were enrolled. Prior adjuvant therapy included: AC (37%), CEF/FEC (28%), AC-T (15%), AT (7%), EC (7%). The median cumulative dose of prior A were 240mg/m2 and 580mg/m2 for doxorubicin or epirubicin, respectively. Median time since adjuvant chemotherapy was 4.4 years (1–14). Patients received a median of 6 cycles (2–10) of PLD + C. Major toxicities were; grade 3/4 neutropenia (7.5%), asymptomatic > 10% declines in LVEF (9%) (reversible upon discontinuation of PLD), grade 3/4 hand foot syndrome (6%). Other toxicities were uncommon and usually did not require discontinuation. The objective response rate (ORR) was 38% (4% CR and 34% PR), with an additional 32% having stable disease > 6 months for a clinical benefit of 70% (CB). ORR was similar for patients who had received adjuvant taxanes. Kaplan-Meyer estimated median time to progression was 31.5 weeks (23% progression free). Conclusions: The combination of PLD + C every 3 weeks in patients who have completed adjuvant anthracycline chemotherapy after more than one year prior is well tolerated and has a clinical benefit rate of 70%. This finding is similar to other commonly employed chemotherapeutic regimens for MBC and suggests that re-treatment with a non-cardiotoxic anthracycline following previous anthracycline therapy may be a reasonable therapeutic option for some patients.

[Table: see text]

Plasma complement C5 protects endothelial cells from polymorphonuclear neutrophil-derived, H2O2-mediated cytotoxicity

BACKGROUND

In vitro studies suggest that polymorphonuclear neutrophils (PMN) can damage endothelial cells (EC) by releasing hydrogen peroxide. In vivo this can lead to anasarca secondary to capillary leakage of fluid, protein, and electrolytes. The result is multiple organ dysfunction syndrome, which is associated with high mortality. In vivo, circulating PMN-EC interactions take place in the presence of plasma, and we have shown previously that plasma affords protection to EC from PMN-mediated damage.

METHODS

Human umbilical vein endothelial cells were primed with cytokines, cultured to a confluent monolayer, and coincubated with normal human PMNs. Cytotoxicity was assayed by gamma scintigraphy, plasma C5 was determined by sepharose column elution, and H(2)O(2) was assayed by R-Phycoerythrin fluorescence.

RESULTS

Addition of C5, but not C3, to RPMI resulted in EC cytoprotection equivalent to adding whole serum. Removal of C5 from serum using F(ab')(2) rabbit IgG anti-human C5 coupled to CNBr-activated 4 sepharose beads resulted in significant loss of EC cytoprotection against H(2)O(2)-mediated damage, whereas adding back C5 restored the cytoprotection. C5 also reduced H(2)O(2)-mediated destruction of R-Phycoerythrin.

CONCLUSIONS

The data suggest that the protection of EC against hydrogen peroxide-mediated damage is partly mediated through complement component C5.

Creatininuria in asthmatic children treated with a combination of glucocorticoid and beta-agonist

We examined whether a combination of glucocorticoids and beta-agonists inhaled by asthmatics had an influence on the metabolism of L-arginine, an amino acid involved in the production of urea, creatinine, and NO that is known to play a significant role in asthma. After lung function tests, we assayed nitrates, urea, and creatinine and determined urinary osmolality in urine samples taken from groups of 129 children (10+/-3 years old) with mild-to-moderate asthma treated with different regimens of drugs. No significant differences in urinary urea levels were noted between the groups. On the other hand, the children treated by the combination of glucocorticoid and beta-agonist (n = 52) had a higher level of urinary creatinine (+40%, P < .001, and a higher creatinine/urea ratio (C/U) expressed as % mass= 5.98 +/- 2.44, P < .001) than did the untreated children (n = 43, C/U = 4.03 +/- 1.24), those treated with glucocorticoid (n = 23, C/U = 4.01 +/- 1.32) or beta-agonist alone (n = 11, C/U = 4.09 +/- 1.01) or control children of the same age (n = 20, C/U = 4.81 +/- .90). Children treated with beta-agonist alone had the lowest mean levels of urinary nitrates (P < .05). The children in group 1 whose C/U ratio was above 6 (n = 24) had a higher FVC (P < .02) and FEV1 (not significant (NS)). However, an overly high C/U may also be indicative of a deleterious influence on the biosynthesis of NO from arginine. Further investigations will be required to determine whether there is a relationship between C/U ratios and lung function parameters, and whether the urinary C/U ratio could be employed as a simple and noninvasive parameter for assessment of treatment in asthmatics.

Exhaled NH3 and excreted Nh4+ in children in unpolluted or urban environments

Exhaled ammonia (NH3ex) was measured by chemiluminescence in a group of healthy children (n = 20) and in two groups of asthmatic children, one (Group 1) residing in a National Park in the mountains (n = 68) and other (Group 2) in an urban area (n = 52). We also determined urinary ammonia, nitrates, urea, sodium and potassium normalized to osmolarity. Unlike exhaled nitric oxide (NOex), NH3ex was not specific to asthma as the children in Group 2 and the controls exhaled more ammonia that did the children in Group 1 (14.3 +/- 10.2 and 14.8 +/- 10.3 vs. 5.6 +/- 4.7 ppb; P < .001, respectively). In the urban environment, all children, including the healthy controls, excreted more ammonia (P < .001) and potassium (P < .001) but less urea (P < .02) than did the children residing in the National Park. These manifestations of moderate metabolic acidosis would favor excretion of ammonia at the expense of urea. In the children residing in the National Park, positive correlations were observed between NH3ex and urinary ammonia, and nitrates, age and morphological parameters. The relationship with the morphological parameters is a reflection of the normal physiological formation of NH3ex. In the children residing in the urban area, the other endogenous source of NH3ex was attributed to a slight disturbance in acid-base balance. In conclusion, the measurement of NH3ex appeared of limited interest, although the higher urinary urea/NH4+ ratio in Group 1 (P < .0001), especially in the treated children, appeared to be linked to the lack of atmospheric pollutants in the National Park. Further experimentation is in progress to confirm these findings.

Exhaled NO in asthmatic children in unpolluted and urban environments

BACKGROUND

NO production (NOex) in the airway epithelium is increased in asthmatic patients and is potently inhibited by anti-inflammatory treatments. The study was designed to compare the: (i) levels of NOex in two groups of asthmatic children residing in different environments (one in a national park in the mountains and the other in a large city) and (ii) the influence of glucocorticoids on levels of NOex between the children and those without treatment.

METHODS

The measurements were performed during the same period in the two locations, 100 km apart. NOex was measured using a chemiluminescence analyzer in controls and two comparable groups of asthmatic children. The first group included 63 children (10+/-3 years) recruited from a specialized institution for asthmatic children, and the second group consisted of 46 asthmatic children (9+/-3 years) living in an urban area. A reference group of 17 healthy children residing in the same city was also studied.

MEASUREMENTS AND RESULTS

The concentrations of NOex in children in the specialized institution were significantly lower (P<.001) than those in asthmatic children living in the city (5.1+/-2.4 vs. 13.8+/-9.3 ppb) and comparable to those in healthy controls (5.3+/-4.0 ppb). In the urban area, NOex levels increased when atmospheric pollution recorded on the previous day had increased. In contrast to that observed in the urban children, glucocorticoids had little influence on the levels of NOex in the children living in the specialized institution.

CONCLUSIONS

Although these relationships need to be confirmed, our findings show that for the determination of NOex, specifying the quality of the environment, in particular, the purity of the air respired by asthmatic children, not only at the time of measurement but also over the previous days, is important.

Combined effect of ascorbic acid and gamma irradiation on microbial and sensorial characteristics of beef patties during refrigerated storage

The present study was undertaken to evaluate the effect of ascorbic acid concentrations (0.03 to 0.5%) and irradiation doses (0.5 to 4 kGy) on microbial growth, color coordinates (L, a, and b), and sensory characteristics (taste and odor) of beef patties during storage at 4 +/- 1 degrees C. Ascorbic acid was also compared to citric acid at a similar pH value in order to differentiate the effects of ascorbic acid from those of pH reduction. Results showed significant reduction (p< or = 0.05) of aerobic plate counts (APCs) and total coliforms, and a significant interaction (p< or = 0.05) between ascorbic acid and irradiation dose was observed. The irradiation treatment had detrimental effects on redness, yellowness, and hue angle values of meat. However, incorporation of ascorbic acid into the meat before irradiation resulted in significant (p< or = 0.05) stabilization of color parameters. The color improvement obtained with ascorbic acid was not related to the pH reduction. Also, no significant detrimental effect on taste or odor was found in irradiated samples containing ascorbic acid.

Cyclooxygenase-2 expression in macrophages: modulation by protein kinase C-alpha

Cyclooxygenase-2 (COX-2) is an inducible enzyme responsible for high levels of PG production during inflammation and immune responses. Previous studies with pharmacological inhibitors suggested a role for protein kinase C (PKC) in PG production possibly by regulating COX-2 expression. In this study, we addressed the role of PKC-alpha in the modulation of COX-2 expression and PGE2 synthesis by the overexpressing of a dominant-negative (DN) mutant of this isoenzyme in the mouse macrophage cell line RAW 264.7. We investigated the effect of various stimuli on COX-2 expression, namely, LPS, IFN-gamma, and the intracellular parasite Leishmania donovani. Whereas LPS-induced COX-2 mRNA and protein expression were down-regulated in DN PKC-alpha-overexpressing clones, IFN-gamma-induced COX-2 expression was up-regulated in DN PKC-alpha-overexpressing clones with respect to normal RAW 264.7 cells. Measurements of PGE2 levels revealed a strong correlation between PGE2 secretion and IFN-gamma-induced COX-2 mRNA and protein levels in DN PKC-alpha-overexpressing clones. Taken together, these results suggest a role for PKC-alpha in the modulation of LPS- and IFN-gamma-induced COX-2 expression, as well as in IFN-gamma-induced PGE2 secretion.

Physiology of hypokinetic and hyperkinetic movement disorders: model for dyskinesia

Although the basal ganglia have been implicated in the development of movement disorders since the 1940s, the exact role played by these structures has remained elusive. The development of the 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine-monkey model of parkinsonism, and the recent resurgence of surgical therapy for the treatment of hypokinetic and hyperkinetic movement disorders has, however, led to an improved understanding of the pathophysiological mechanisms that underlie their development. In this article, we review the functional organization and examine the changes in neuronal activity that occur in the basal ganglia thalamocortical 'motor' circuit in these disorders. An alternative to the classic 'rate' model for Parkinson's disease is presented that incorporates the observed changes in neuronal activity, as well as additional neuronal pathways that contribute to these changes. Based on studies in animal models and humans with hyperkinetic movement disorders, it is postulated that dyskinesias develop as the result of a combination of excessive reductions in the mean discharge rate, altered patterns and increased synchronization of neurons in the internal segment of the globus pallidus. It is further postulated that the particular type of involuntary movement which develops also depends on the relative change in neuronal activity in the direct, indirect and alternative pathways. Support for these postulates is examined, and models for drug-induced dyskinesia, hemiballismus and dystonia are proposed.

Atmospheric NO, temperature and ischaemic heart disease. Study in Toulouse and its conurbation

Over a period of 388 days, associations were sought between the occurrence of acute myocardial infarction (AMI), levels of atmospheric nitrogen-containing gases (NO, NO2, NH3), temperature and relative humidity. During this period, there were 282 AMI validated by the WHO-MONICA criteria. Analysis of the data revealed, a decrease in the area, in AMI, when daily nitric oxide levels were above 13 microg m(-3) and when the mean daily temperature was below 13 degrees C.