The Role of CCL24 in Systemic Sclerosis

Systemic sclerosis (SSc) is a chronic immune-mediated disease characterized by microangiopathy, immune dysregulation, and progressive fibrosis of the skin and internal organs. Though not fully understood, the pathogenesis of SSc is dominated by microvascular injury, endothelial dysregulation, and immune response that are thought to be associated with fibroblast activation and related fibrogenesis. Among the main clinical subsets, diffuse SSc (dSSc) is a progressive form with rapid and disseminated skin thickening accompanied by internal organ fibrosis and dysfunction. Despite recent advances and multiple randomized clinical trials in early dSSc patients, an effective disease-modifying treatment for progressive skin fibrosis is still missing, and there is a crucial need to identify new targets for therapeutic intervention. Eotaxin-2 (CCL24) is a chemokine secreted by immune cells and epithelial cells, which promotes trafficking of immune cells and activation of pro-fibrotic cells through CCR3 receptor binding. Higher levels of CCL24 and CCR3 were found in the skin and sera of patients with SSc compared with healthy controls; elevated levels of CCL24 and CCR3 were associated with fibrosis and predictive of greater lung function deterioration. Growing evidence supports the potency of a CCL24-blocking antibody as an anti-inflammatory and anti-fibrotic modulating agent in multiple preclinical models that involve liver, skin, and lung inflammation and fibrosis. This review highlights the role of CCL24 in orchestrating immune, vascular, and fibrotic pathways, and the potential of CCL24 inhibition as a novel treatment for SSc.

The Roles of Coagulation Disorder and Microthrombosis in Sepsis: Pathophysiology, Diagnosis, and Treatment

The diagnostic criteria of overt disseminated intravascular coagulation (DIC) were established by the International Society on Thrombosis and Haemostasis (ISTH) in 2001. Since then, DIC has long been associated with adverse outcomes. However, recent advances in sepsis shed light on the role of coagulation disorders in the progression of sepsis. Currently, inflammation and coagulation are recognized as the two drivers that promote organ dysfunction in sepsis and septic shock. The ISTH has published new diagnostic criteria for improved management, namely sepsis-induced coagulopathy (SIC), in 2017. SIC is a pragmatic scoring system composed of platelet count, prothrombin time, and organ dysfunction score to detect the early-stage of sepsis-associated DIC. Since overt DIC represents an uncompensated coagulation disorder, a two-step approach using SIC and overt DIC criteria is a novel strategy to evaluate the severity and manage this challenging complication. Although there is no globally agreed on anticoagulant therapy for DIC, the Japanese Surviving Sepsis Campaign Guidelines 2020 recommend using antithrombin and recombinant thrombomodulin for sepsis associated DIC. Since research in this area has been previously reported, an international collaborative study is necessary to develop future diagnostic tools and treatment strategies.

Expected delay analysis of polling systems in heavy traffic

We study the expected delay in a cyclic polling model with mixtures of exhaustive and gated service in heavy traffic. We obtain closed-form expressions for the mean delay under standard heavy-traffic scalings, providing new insights into the behaviour of polling systems in heavy traffic. The results lead to excellent approximations of the expected waiting times in practical heavy-load scenarios and moreover, lead to new results for optimizing the system performance with respect to the service disciplines.

Refining the continuum of CFTR-associated disorders in the era of newborn screening

Clinical heterogeneity in cystic fibrosis (CF) often causes diagnostic uncertainty in infants without symptoms and in older patients with milder phenotypes. We performed a cross-sectional evaluation of a comprehensive set of clinical and laboratory descriptors in a physician-defined cohort (N = 376; Children's Hospital of Wisconsin and the American Family Children's Hospital CF centers in Milwaukee and Madison, WI, USA) to determine the robustness of categorizing CF (N = 300), cystic fibrosis transmembrane conductance regulator (CFTR)-related disorder (N = 19), and CFTR-related (CRMS) metabolic syndrome (N = 57) according to current consensus guidelines. Outcome measures included patient demographics, clinical measures, sweat chloride levels, CFTR genotype, age at diagnosis, airway microbiology, pancreatic function, infection, and nutritional status. The CF cohort had a significantly higher median sweat chloride level (105 mmol/l) than CFTR-related disorder patients (43 mmol/l) and CFTR-related metabolic syndrome patients (35 mmol/l; p ≤ 0.001). Patient groups significantly differed in pancreatic sufficiency, immunoreactive trypsinogen levels, sweat chloride values, genotype, and positive Pseudomonas aeruginosa cultures (p ≤ 0.001). An automated classification algorithm using recursive partitioning demonstrated concordance between physician diagnoses and consensus guidelines. Our analysis suggests that integrating clinical information with sweat chloride levels, CFTR genotype, and pancreatic sufficiency provides a context for continued longitudinal monitoring of patients for personalized and effective treatment.

Transcriptional signatures as a disease-specific and predictive inflammatory biomarker for type 1 diabetes

The complex milieu of inflammatory mediators associated with many diseases is often too dilute to directly measure in the periphery, necessitating development of more sensitive measurements suitable for mechanistic studies, earlier diagnosis, guiding therapeutic decisions and monitoring interventions. We previously demonstrated that plasma samples from recent-onset type 1 diabetes (RO T1D) patients induce a proinflammatory transcriptional signature in freshly drawn peripheral blood mononuclear cells (PBMCs) relative to that of unrelated healthy controls (HC). Here, using cryopreserved PBMC, we analyzed larger RO T1D and HC cohorts, examined T1D progression in pre-onset samples, and compared the RO T1D signature to those associated with three disorders characterized by airway infection and inflammation. The RO T1D signature, consisting of interleukin-1 cytokine family members, chemokines involved in immunocyte chemotaxis, immune receptors and signaling molecules, was detected during early pre-diabetes and found to resolve post-onset. The signatures associated with cystic fibrosis patients chronically infected with Pseudomonas aeruginosa, patients with confirmed bacterial pneumonia, and subjects with H1N1 influenza all reflected immunological activation, yet each were distinct from one another and negatively correlated with that of T1D. This study highlights the remarkable capacity of cells to serve as biosensors capable of sensitively and comprehensively differentiating immunological states.

Cystic fibrosis mutations for p.F508del compound heterozygotes predict sweat chloride levels and pancreatic sufficiency

Cystic fibrosis (CF) is a monogenetic disease with a complex phenotype. Over 1500 mutations in the CFTR gene have been identified; however, the p.F508del mutation is most common. There has been limited correlation between the CFTR mutation genotype and the disease phenotypes. We evaluated the non-p.F508del mutation of 108 p.F508del compound heterozygotes using the biological classification method, Grantham and Sorting Intolerant from Tolerant (SIFT) scores to assess whether these scoring systems correlated with sweat chloride levels, pancreatic sufficiency, predicted FEV(1) , and risk of infection with Pseudomonas aeruginosa in the last year. Mutations predicted to be 'mild' by the biological classification method are associated with more normal sweat chloride levels (p < 0.001), pancreatic sufficiency (p < 0.001) and decreased risk of infection with Pseudomonas in the last year (p = 0.014). Lower Grantham scores are associated with more normal sweat chloride levels (p < 0.001), and pancreatic sufficiency (p = 0.014). Higher SIFT scores are associated with more normal sweat chloride levels (p < 0.001) and pancreatic sufficiency (p = 0.011). There was no association between pulmonary function measured by predicted FEV(1) and the biological classification (p = 0.98), Grantham (p = 0.28) or SIFT scores (p = 0.62), which suggests the pulmonary disease related to CF may involve other modifier genes and environmental factors.

Characterization of brain lesions in a mouse model of progressive multiple sclerosis

Multiple sclerosis (MS) is an autoimmune disease of the central nervous system characterized by damage to the neuronal myelin sheath, which results in different levels of muscle paralysis that can lead to neuronal death. In most MS mouse models, the neurologic damage mostly affects the spinal cord with limited damage to the brain, which cannot be monitored by magnetic resonance imaging (MRI) as used for humans. We show that immunization of non-obese diabetic (NOD) mice with myelin oligodendrocyte glycoprotein peptide 35-55 leads to the development of relapsing-remitting stages, evident from days 20 to 70, which then develops into a chronic progressive stage. This cycle is similar to MS stages found in humans. Brain MRI gadolinium-enhanced T1-weighted image analysis showed an increased blood-brain barrier permeability in brain gray and white matter specific to the corpus callosum, fimbria, and internal capsule as found in humans. MRI fractional anisotropy analysis showed demyelination and axonal damage in identical regions. Immunohistologic analysis supported the MRI data. No evidence of brain lesions was found in a common model of MS using C57BL/6 mice. We suggest that an increase in astrocyte toxicity in experimental autoimmune encephalomyelitis-induced NOD mice may be linked to brain lesion development. We suggest using NOD mice as a suitable model for studying MS using MRI methods toward future diagnostic and drug development.

Biochemical characterization of mutant phenylalanine hydroxylase enzymes and correlation with clinical presentation in hyperphenylalaninaemic patients

The biochemical properties of mutant phenylalanine hydroxylase (PAH) enzymes and clinical characteristics of hyperphenylalaninaemic patients who bear these mutant enzymes were investigated. Biochemical characterization of mutant PAH enzymes p.D143G, p.R155H, p.L348V, p.R408W and p.P416Q included determination of specific activity, substrate activation, V(max), K(m) for (6R)-L-erythro-5,6,7,8-tetrahydrobiopterin (BH(4)), K (d) for BH(4), and protein stabilization by BH(4). Clinical data from 22 patients either homozygous, functionally hemizygous, or compound heterozygous for the mutant enzymes of interest were correlated with biochemical parameters of the mutant enzymes. The p.L348V and p.P416Q enzymes retain significant catalytic activity yet were observed in classic and moderate PKU patients. Biochemical studies demonstrated that BH(4) rectified the stability defects in p.L348V and p.P416Q; additionally, patients with these variants responded to BH(4) therapy. The p.R155H mutant displayed low PAH activity and decreased apparent affinity for L-Phe yet was observed in mild hyperphenylalaninaemia. The p.R155H mutant does not display kinetic instability, as it is stabilized by BH(4) similarly to wild-type PAH; thus the residual activity is available under physiological conditions. The p.R408W enzyme is dysfunctional in nearly all biochemical parameters, as evidenced by disease severity in homozygous and hemizygous patients. Biochemical assessment of mutant PAH proteins, especially parameters involving interaction with BH(4) that impact protein folding, appear useful in clinical correlation. As additional patients and mutant proteins are assessed, the utility of this approach will become apparent.

Kinetics of the appearance of Marek's disease virus DNA and antigens in the feathers of chickens

A comparison was made of the temporal appearance of six isolates of serotype 1 Marek's disease virus (MDV) in the feathers of specific pathogen-free (SPF) infected birds using three assays: agar gel precipitation (AGP), enzyme-linked immunosorbent assay (ELISA) and dot-blot DNA hybridisation. Isolate GA-5 served to standardise the in vivo pathogenicity assay, while the remaining five were recent isolates from Israel. Each isolate was inoculated into susceptible 4-day-old birds housed with an equal number of uninoculated birds. All six caused high mortality (80 to 100%) in the inoculated birds and a wide range of mortality (15 to 80%) in the contact groups. The transmission of infection from the inoculated group to the contact group was demonstrated for all six isolates by AGP and ELISA and for four isolates by dot-blot hybridisation. The other two isolates either showed a concurrent rise in MDV-DNA levels (isolate B) or failed to produce detectable levels of DNA in the inoculated and contact infected groups (isolate Ab). This could be due to the nature of the hybridisation reaction between the probe and the homologous sequence in the genome of isolate Ab. Antigenic activity was detected 11 days post-injection by ELISA, 14 days by AGP in some of the inoculated groups. In the contact infected birds the ELISA and dot-blot assays detected virus about 14 days earlier than did AGP. The time interval between the first detection of virus in the inoculated as compared with the contact infected groups differed for each assay and each isolate, viz; 10 to 14 days by ELISA, 14 to 24 days by AGP and 11 to 18 days by DNA-hybridisation.

Nitric oxide modulates the transfer function between cones and horizontal cells during changing conditions of ambient illumination

It has been suggested that nitric oxide (NO) serves as a retinal neuromodulator, adjusting retinal function to changing conditions of adaptation. We tested this hypothesis in the intact turtle retina by recording the photoresponses of L-cones and L1-horizontal cells, while changing retinal NO level and background illumination. Raising the retinal level of NO, by adding an NO donor (sodium nitroprusside) or the precursor for NO synthesis (L-arginine), induced response augmentation in L-cones and L1-horizontal cells. Lowering retinal level of NO by adding L-NAME, an inhibitor of NO synthesis, reduced the amplitudes of the photoresponses in these retinal neurons. The transfer function between L-cones and L1-horizontal cells, constructed from the photoresponses of these cells, was modified by NO and by background lights. The nonlinear transfer function, characteristic of the dark-adapted retina, became linear and of low gain when the retinal NO level was increased or by increasing the level of ambient illumination. In contrast, inhibiting NO synthesis in the light-adapted retina induced nonlinearity in the cone-to-horizontal cell transfer function similar to that seen in the dark-adapted state. NADPH diaphorase histochemistry, conducted on isolated retinal cells, demonstrated activity in cone inner segments and distal process of Müller cells. These findings support the hypothesis that NO synthesis in the distal turtle retina is triggered by background illumination, and that NO acts to adjust the modes of visual information processing in the outer plexiform layer to the conditions required during continuous background illumination.

The Resource Mothers Study of Maternal Phenylketonuria: preliminary findings

Women with phenylketonuria (PKU) must follow a strict low-phenylalanine diet during pregnancy in order to protect the fetus from the deleterious effects of high maternal blood phenylalanine. The Resource Mothers Study of Maternal PKU was undertaken to determine whether a home visitation programme was effective in helping women with PKU attain blood phenylalanine control earlier during pregnancy. Resource Mothers were trained to provide social support and practical assistance to women with PKU during pregnancy. Eight metabolic clinics in the United States participated in the study. Women with PKU who were planning pregnancy or already pregnant were enrolled in the study and were treated with a low-phenylalanine diet aimed at controlling blood phenylalanine to 120-360 micromol/L. They were randomly assigned to receive the services of a Resource Mother (RM group) or to a control group. Fifty women were enrolled, and accounted for 44 pregnancies which resulted in 28 live births, and 6 spontaneous abortions. Ten women are currently pregnant and another 6 have not become pregnant. Fifty-six percent of enrolled women began the diet prior to becoming pregnant. Fifty-three percent of women in the Resource Mother group were in metabolic control by 10 weeks gestation as compared to 39% in the control group. In addition, women who began diet after pregnancy and had a Resource Mother attained metabolic control earlier (mean gestational age of 22.4 weeks in the RM group vs 29.8 weeks in the control group). There was no difference in birth measurement z -scores of offspring born to women in the RM group compared to controls. All but 4 women rated themselves as feeling worse about the diet at the end of pregnancy than at the beginning, and few women in either group remained on diet after delivery.

Does the incidence of group health insurance fall on individual workers?

Economic models predict that the cost of health insurance is borne by workers. In this paper we ask two questions. First, is cost shifting individual-specific: does a worker with higher expected medical expenses bear this cost? Second, how do explicit employee contributions affect cost shifting? We estimate wage change regressions that include as explanatory variables changes in health insurance coverage, changes in employee premium contributions, health status, and an interaction between health insurance changes and health status. We find no evidence of a significant wage offset at either the individual or group level and conclude that changes in health insurance status are not exogenous.

Spatial-chromatic interactions in C-type horizontal cells of the turtle (Mauremys caspica) retina

Horizontal cells are second-order retinal neurons that play a key role in spatial information processing. In some cold-blooded vertebrates such as turtles, a subtype of these cells, the chromaticity horizontal cells exhibit color-opponent responses and therefore are considered to be important also for color information processing. To reveal spatial and color interactions, the receptive-field properties of Red/Green and Yellow/Blue chromaticity horizontal cells in the retina of the turtle Mauremys caspica were studied by intracellular recordings from the everted eyecup preparation. We found that the polarity of the photoresponses depended not only upon the wavelength and intensity of the stimulus, but also upon its spatial configuration. Thus, a hyperpolarizing photoresponse that was elicited by full-field stimulation with bright light of wavelength close to the "neutral" one was reversed in polarity to a pure depolarizing one when a small spot or a thin annular pattern were used for stimulation. This finding could not be explained either by different balances between depolarizing and hyperpolarizing inputs to different cells or by stray light that effectively reduced the light intensity in the center of the small spot. Rather, it was found that the depolarizing and hyperpolarizing components were characterized by different receptive-field size and that these differences could account for the dependency of response polarity upon the spatial pattern of the stimulus. These findings indicate that color information processing in turtle C-type horizontal cells is a complex process that depends upon the wavelength and intensity of the light stimulus as well as upon its spatial properties.

Treatment of systemic inflammatory response syndrome by push-pull powdered sorbent pheresis: a Phase 1 clinical trial

An FDA-approved Phase 1 feasibility study was performed in two centers to determine the safety of the BioLogic-DTPF (detoxifier/plasma filter) system for the treatment of patients with systemic inflammatory response syndrome (SIRS). This device combines hemodiabsorption (dialysis of blood against powdered sorbents with the BioLogic-DT system) with push-pull sorbent-based pheresis (the PF add-on module). Eight adult ICU patients with both SIRS and multiple organ failure participated in the study. One 6 h treatment was planned for each patient with powdered charcoal as sorbent for 4 patients and a combination of charcoal/silica in the PF sorbent bag for 4 patients. The treatments appeared to have no negative effects in 7 patients, but 1 patient died during treatment due to progressive cardiac failure. Sepsis was resolved in 5 of the 8 patients. However, there were only 2 long-term survivors of the group. The addition of the PF module should improve the chemical function of the BioLogic-DT by allowing removal of protein-bound toxins such as cytokines. The selected patients tolerated treatment by the DTPF system well, but proof of benefit of the device remains to be proven in a Phase 2 clinical trial with randomized controls.

Turtle C-type horizontal cells act as push-pull devices

Chromaticity (C-type) horizontal cells in the retina of cold-blooded vertebrates receive antagonistic inputs from cone photoreceptors of different spectral types leading to color opponency. The relative contribution of each spectral type of cones can be selectively altered by chromatic background illumination. Therefore, the spectral properties of C-type horizontal cells are expected to change when the intensity and color of ambient illumination are altered. In this study, we investigated the effects of chromatic background lights upon color opponency in Red/Green (RGH) and Yellow/Blue (YBH) C-type horizontal cells in the everted eyecup preparation of the turtle Mauremys caspica. Photoresponses were elicited by long-wavelength and short-wavelength light stimuli in the dark-adapted state and under conditions of chromatic background illumination. We found that the total voltage range. within which graded depolarizing and the hyperpolarizing photoresponses could be elicited, either increased or decreased depending upon the color of the background light. However, the maximal and minimal potential levels determined respectively by long-wavelength and short-wavelength light stimuli of supersaturating intensity remained unchanged, regardless of the wavelength and intensity of the background. These findings indicate that turtle C-type horizontal cells operate as push-pull devices. A sufficiently bright short-wavelength stimulus can push them all the way to the maximal hyperpolarizing level while a very bright long-wavelength stimulus can pull them towards the most depolarizing potential.

Gastric feeding with erythromycin is equivalent to transpyloric feeding in the critically ill

OBJECTIVE

To determine whether adding erythromycin to a gastric feeding regimen could render it as effective in meeting nutritional needs as transpyloric feeding.

DESIGN

Randomized, controlled study.

SETTING

University hospital medical, surgical, and neurologic care intensive care units.

PATIENTS

Critically ill patients, requiring a projected 96 hrs of enteral feeding, who had no specific indication for tube location (gastric or transpyloric). Eighty patients were randomized.

INTERVENTIONS

Patients were randomized to gastric feeding with erythromycin (200 mg iv) given every 8 hrs or feeding through a transpylorically placed feeding tube. Goal rate and feeding advancement were determined by protocol.

MEASUREMENTS AND MAIN RESULTS

During the 96-hr period, the gastric group received 74% of their goal calories and the transpyloric group received 67%. The only day on which gastric feedings were superior was the first study day, where the gastric group attained 55% of their goal, compared with 44% in the transpyloric group. This 1-day difference was the result of an initial failure of tube placement in some subjects. Exclusion of these patients did not change overall results. Nutritional indexes, length of stay in the intensive care unit, ventilator dependence, and survival were not different between the two groups.

CONCLUSIONS

Gastric feeding with erythromycin as a prokinetic is equivalent to transpyloric feeding in meeting the nutritional goals of the critically ill.

Disseminated histoplasmosis presenting as pyoderma gangrenosum-like lesions in a patient with acquired immunodeficiency syndrome

A 33-year-old Hispanic woman with newly diagnosed human immunodeficiency virus (HIV) infection, a CD4 T-lymphocyte count of 2, viral load of 730,000 copies/mL, candidal esophagitis, seizure disorder, a history of bacterial pneumonia, and recent weight loss was admitted with tonic clonic seizure. On admission, her vital signs were: pulse of 88, respiration rate of 18, temperature of 37.7 degrees C, and blood pressure of 126/76. Her only medication was phenytoin. On examination, the patient was found to have multiple umbilicated papules on her face, as well as painful, erythematous, large, punched-out ulcers on the nose, face, trunk, and extremities of 3 months' duration (Fig. 1). The borders of the ulcers were irregular, raised, boggy, and undermined, while the base contained hemorrhagic exudate partially covered with necrotic eschar. The largest ulcer on the left mandible was 4 cm in diameter. The oral cavity was clear. Because of her subtherapeutic phenytoin level, the medication dose was adjusted, and she was empirically treated with Unasyn for presumptive bacterial infection. Chest radiograph and head computed tomography (CT) scan were within normal limits. Sputum for acid-fast bacilli (AFB) smear was negative. Serologic studies, including Histoplasma antibodies, toxoplasmosis immunoglobulin M (IgM), rapid plasma reagin (RPR), hepatitis C virus (HCV), and hepatitis B virus (HBV) antibodies were all negative. Examination of the cerebrospinal fluid was within normal limits without the presence of cryptococcal antigen. Blood and cerebrospinal cultures for bacteria, mycobacteria, and fungi were all negative. Viral culture from one of the lesions was also negative. The analysis of her complete blood count showed: white blood count, 2300/microl; hemoglobin, 8.5 g/dL; hematocrit, 25.7%; and platelets, 114,000/microl. Two days after admission, the dermatology service was asked to evaluate the patient. Although the umbilicated papules on the patient's face resembled lesions of molluscum contagiosum, other infectious processes considered in the differential diagnosis included histoplasmosis, cryptococcosis, and Penicillium marnefei. In addition, the morphology of the ulcers, particularly that on the left mandible, resembled lesions of pyoderma gangrenosum. A skin biopsy was performed on an ulcer on the chest. Histopathologic examination revealed granulomatous dermatitis with multiple budding yeast forms, predominantly within histiocytes, with few organisms residing extracellularly. Methenamine silver stain confirmed the presence of 2-4 microm fungal spores suggestive of Histoplasma capsulatum (Fig. 2). Because of the patient's deteriorating condition, intravenous amphotericin B was initiated after tissue culture was obtained. Within the first week of treatment, the skin lesions started to resolve. Histoplasma capsulatum was later isolated by culture, confirming the diagnosis. The patient was continued on amphotericin B for a total of 10 weeks, and was started on lamivudine, stavudine, and nelfinavir for her HIV infection during hospitalization. After amphotericin B therapy, the patient was placed on life-long suppressive therapy with itraconazole. Follow-up at 9 months after the initial presentation revealed no evidence of relapse of histoplasmosis.

Hantavirus pulmonary syndrome due to Andes virus in Temuco, Chile: clinical experience with 16 adults

STUDY OBJECTIVES

To describe the clinical features and laboratory abnormalities of 16 adults with confirmed Hantavirus pulmonary syndrome (HPS) due to Andes virus in Temuco, Chile.

DESIGN

A retrospective chart review abstracting clinical, radiologic, laboratory, and epidemiologic data.

SETTING

ICU of the university teaching hospital in Temuco, Chile.

PATIENTS

Sixteen patients with HPS treated between 1997 and 1999.

RESULTS

Patients were aged from 19 to 45 years, 82% were men, and 88% were farm or timber workers with occupational acquisition of HPS. After an incubation period ranging from 5 to 25 days, a prodromal influenza-like phase frequently was accompanied by abdominal symptoms. From 1 to 7 days later, respiratory insufficiency and hemodynamic instability suddenly appeared. In 81%, hemorrhage was evident; in 63%, moderate-to-severe bleeding occurred. The most prominent laboratory abnormalities were hemoconcentration, leukocytosis, thrombocytopenia, altered partial thromboplastin time (PTT), creatine kinase, transaminases, and hyponatremia. Creatinine elevation was common, with clinical importance in two patients. All patients had severe hypoxemia and pulmonary edema. Fifteen patients received supportive treatment, and 5 patients were treated with corticosteroids. The mortality rate was 43.8%.

CONCLUSIONS

Bad prognostic factors appeared to be severe hypotension, lower PaO(2)/fraction of inspired oxygen values, prolonged PTT, hemorrhage, greater volume load, and profuse bronchorrhea. The effects of treatment with corticosteroids could not be determined. Hemorrhage and renal involvement were common in our patients, features not often described in the North American literature of Sin Nombre virus HPS.

Trace element homeostasis during continuous sedation with propofol containing EDTA versus other sedatives in critically ill patients

OBJECTIVE

To evaluate changes in serum and urinary zinc, cobalt, copper, iron, and calcium concentrations in critically ill patients receiving propofol containing disodium edetate (disodium ethylenediaminetetraacetic acid [EDTA]) versus sedative agents without EDTA.

DESIGN

This was a randomised, open-label, parallel-group study with randomisation stratified by baseline Acute Physiology and Chronic Health Evaluation (APACHE II) scores.

SETTING

Intensive care units (ICU) in 23 medical centres.

PATIENTS

Medical, surgical, or trauma ICU patients 17 years of age or older who required mechanical ventilator support and sedation.

INTERVENTIONS

A total of 106 patients received propofol containing 0.005 % EDTA (propofol EDTA), and 104 received other sedative agents without EDTA (non-EDTA). Only the first 108 patients were assessed for urinary trace metal excretion. Twenty-four-hour urine samples were collected on days 2, 3, and 7 and every 7 days thereafter for determination of zinc, cobalt, copper, iron, and calcium excretion; EDTA levels; urine osmolality; albumin levels; and glucose levels. The first 143 patients were assessed for serum concentration of zinc, cobalt, copper, iron, and calcium; creatinine; blood urea nitrogen; and albumin at baseline and once during each 24-hour urine collection.

MEASUREMENTS AND RESULTS

For the assessment of trace metals, patients receiving propofol EDTA demonstrated increased mean urinary excretion of zinc, copper, and iron compared with the normal range. All patients receiving sedatives demonstrated increased urinary excretion of zinc and copper above normal reference values. Compared with the non-EDTA sedative group, the propofol EDTA group demonstrated increased urinary excretion of zinc and iron. Mean serum concentrations of zinc and total calcium were decreased in both patient groups. Serum zinc concentrations increased from baseline to day 3 in the non-EDTA sedative group but not in the propofol EDTA group. Renal function, measured by blood urea nitrogen, serum creatinine, and creatinine clearance, did not deteriorate during ICU sedation with either regimen.

CONCLUSION

This study showed that critical illness is associated with increased urinary losses of zinc, copper, and iron. Propofol EDTA-treated patients had greater urinary losses of zinc and iron and lower serum zinc concentrations compared with the non-EDTA sedative group. No adverse events indicative of trace metal deficiency were observed in either group. The clinical significance of trace metal losses during critical illness is unclear and requires further study.

Equal aspiration rates in gastrically and transpylorically fed critically ill patients

OBJECTIVES

To determine the difference in aspiration rates between gastrically and transpylorically fed patients in the intensive care unit.

DESIGN

A prospective controlled study of critically ill patients randomized to receive either a gastrically placed feeding tube or a transpylorically placed feeding tube.

SETTING

University teaching hospital's medical intensive care unit. The study was conducted over 14 months.

PATIENTS

Fifty-four critically ill subjects (with an overall 40% mortality) with similar baseline age, severity of illness, and nutritional needs requiring enteral nutrition, with 51 completing the study.

INTERVENTIONS

All feeds were tagged with technetium-99m radiolabeled sulfur colloid, and the pulmonary secretions or lungs of each patient were scanned on a daily basis to determine whether aspiration had occurred. Patients were fed according to their assigned tube placement which was verified daily by continuous electromyography.

MEASUREMENTS AND RESULTS

Of 27 gastrically fed patients 2 (7%) had evidence of scanned feed in pulmonary secretions or the lung, compared to 3 of 24 (13%) transpylorically fed patients (n.s.). Clinical suspicion of aspiration was insensitive and detected only 60% of isotopically documented aspirations with a positive predictive value of 27%.

CONCLUSION

There was no difference in aspiration rates between gastrically and transpylorically fed critically ill patients.

Confirming the reliability of the sedation-agitation scale administered by ICU nurses without experience in its use

STUDY OBJECTIVES

To determine the validity and reliability of the Sedation-Agitation scale (SAS) when administered by intensive care unit (ICU) nurses with no experience in its use.

DESIGN

Prospective, psychometric evaluation.

SETTING

Adult medical-cardiac ICU.

PATIENTS

Sixty patients.

INTERVENTION

Sedation and agitation were observed simultaneously but independently by nurses and two investigators, and patients were rated with the SAS. The assessment of an experienced clinical nurse specialist was recorded on visual analog scales (VAS) for sedation (VAS-S) and agitation (VAS-A).

MEASUREMENTS AND MAIN RESULTS

The SAS scores of ICU staff nurses were compared with VAS scored by the clinical nurse specialist using Pearson correlation coefficient. The SAS correlated well with VAS-S (Spearman's p = -0.77, p<0.001). Neither SAS nor VAS-A was correlated (Spearman's p = 0.05, p>0.5), but there were few observations of agitated patients. The SAS interrater agreement was excellent between the two trained investigators (weighted K = 0.93, p<0.001) and between investigators and staff nurses (weighted K = 0.85 and 0.87, p<0.001 for both).

CONCLUSION

The SAS is reliable when administered by staff nurses with no experience with it. Due to the paucity of observations of agitated patients, we were unable to determine its validity for assessing agitation.

Role of common gene variations in the molecular pathogenesis of short-chain acyl-CoA dehydrogenase deficiency

ABSTRACT Short-chain acyl-CoA dehydrogenase (SCAD) deficiency is considered a rare inherited mitochondrial fatty acid oxidation disorder. Less than 10 patients have been reported, diagnosed on the basis of ethylmalonic aciduria and low SCAD activity in cultured fibroblast. However, mild ethylmalonic aciduria, a biochemical marker of functional SCAD deficiency in vivo, is a common finding in patients suspected of having metabolic disorders. Based on previous observations, we have proposed that ethylmalonic aciduria in a small proportion of cases is caused by pathogenic SCAD gene mutations, and SCAD deficiency can be demonstrated in fibroblasts. Another - much more frequent - group of patients with mild ethylmalonic aciduria has functional SCAD deficiency due to the presence of susceptibility SCAD gene variations, i.e. 625G>A and 511C>T, in whom a variable or moderately reduced SCAD activity in fibroblasts may still be clinically relevant. To substantiate this notion we performed sequence analysis of the SCAD gene in 10 patients with ethylmalonic aciduria and diagnosed with SCAD deficiency in fibroblasts. Surprisingly, only one of the 10 patients carried pathogenic mutations in both alleles, while five were double heterozygotes for a pathogenic mutation in one allele and the 625G>A susceptibility variation in the other. The remaining four patients carried only either the 511C>T or the 625G>A variations in each allele. Our findings document that patients carrying these SCAD gene variations may develop clinically relevant SCAD deficiency, and that patients with even mild ethylmalonic aciduria should be tested for these variations.

The International Collaborative Study of Maternal Phenylketonuria: status report 1998

The Maternal Phenylketonuria Study began in 1984 and during the intervening years, 572 pregnancies in hyperphenylalaninemic women and 99 controls and their outcomes have been evaluated. Among hyperphenylalaninemic women who delivered a live infant, only 15.9% were treated and in metabolic control preconceptually, however, another 18.4% were in control by 10 weeks. Compared to the results reported by Lenke and Levy in 1980, there is a marked improvement in outcome with treatment. Microcephaly was unusual in preconceptually treated pregnancies with well controlled phenylalanine restricted diets. Even in pregnancies that established control after conception but before the 8th week, congenital heart disease did not occur in the offspring, however, it did occur in 12% of pregnancies not achieving control until after 10 weeks of pregnancy.

CONCLUSION

The recommended level of blood phenylalanine during pregnancy is 120-360 mumol/l. Best results were obtained by close cooperation between the attending obstetrician and a metabolic team experienced in the care of persons with phenylketonuria.

Maternal phenylketonuria: an international study

Maternal phenylketonuria (PKU) syndrome results in multiple congenital anomalies in the offspring, usually consisting of microcephaly, intrauterine growth retardation, dysmorphology, and congenital heart disease. Pregnancies treated preconceptionally with a phenylalanine-restricted diet and control of maternal blood phenylalanine levels within the recommended range result in normal offspring. However, in this 15-year study, several significant factors resulted in microcephaly in 27% of the offspring, and 7% exhibited serious congenital heart disease. These results occurred chiefly in women with mean IQ scores of 83 associated with low socioeconomic status and decreased educational achievement. Another important factor associated with suboptimal control of blood phenylalanine levels during pregnancy was the fact that most pregnancies were not carefully planned and occurred in women off dietary treatment with phenylalanine-restricted products. These results indicate that greater effort must be developed to assist women with PKU in remaining on diet during their reproductive years. It appears that continued adherence to the diet, resulting in normal maternal intelligence, is an important contribution to improved fetal development.

A multicenter, prospective study of the placement of transpyloric feeding tubes with assistance of a magnetic device. The Magnet-Guided Enteral Feeding Tube Study Group

BACKGROUND

Placement of feeding tubes in the transpyloric position can be helpful in the management of enterally fed patients with pancreatitis, gastric atony, enterocutaneous fistulae, or pulmonary aspiration risk. The attainment of transpyloric position is difficult, and numerous techniques have been proposed to help in achieving this location. Recently, the use of a magnet-tipped feeding tube, dragged into proper position with an external magnet, has been described with an excellent success rate.

METHODS

At 10 participating institutions, practitioners were trained in the use of the device. Successful tube placement was determined by abdominal radiograph.

RESULTS

One hundred fifty-six tube placements were attempted. Transpyloric position was obtained in 60%. Placement into the third portion of the duodenum or distal was obtained in only 32%. Analysis of the data did not reveal a learning curve at the institutions, and 7 of 10 had a 50% or lower success rate.

CONCLUSIONS

Placement of feeding tubes with the assistance of a magnetic device was infrequently successful at the majority of institutions where it was attempted. We report a lower success rate than the original article, which described an 88% success rate of transpyloric intubation. Although this technique has a high failure rate, some individuals seem to be very successful using it, which could reduce the need for endoscopy or transport for the placement of feeding tubes.

Push-pull sorbent-based pheresis and hemodiabsorption in the treatment of hepatic failure: preliminary results of a clinical trial with the BioLogic-DTPF System

The BioLogic-DTPF System combines hemodiabsorption (the BioLogic-DT System with dialysis against powdered sorbent) with push-pull sorbent-based pheresis (the BioLogic-PF System with powdered sorbent surrounding plasma filters). At blood flow rates of 200 ml/min, the system clears creatinine and aromatic amino acids at 120-160 ml/min, unconjugated bilirubin at 20-40 ml/min, and cytokines at 15-25 ml/min. This article outlines a study of the DTPF System in treatment of patients with hepatic failure with Grade 3 or 4 encephalopathy and respiratory and kidney insufficiency. Treatment appeared to be safe, and there are no significant hematologic changes. Physiologic changes include improved blood pressure and encephalopathy and stable urine output. Chemical changes include decrease in plasma levels of bilirubin, aromatic amino acids, ammonium, creatinine, and interleukin-3 (IL-1beta). The BioLogic-DT System is now marketed for treatment of acute hepatic failure with encephalopathy. The BioLogic-DTPF System adds the capability of removing bilirubin and other strongly protein-bound toxins from treated patients and may be of clinical benefit in management of patients with the most severe hepatic failure and encephalopathy.

The role of feedback in manual tracking of visual targets

The role of visual feedback in manual tracking was investigated in 24 subjects who tracked 5-, 10-, and 40-mm/diameter targets, moving on a screen at 18 to 25 mm/sec., along various paths, by moving an unseen handle over a digitizing tablet. A cursor indicating instantaneous handle position was visible at all times on half the trials and hidden within a circle coaxial with the target but double its diameter in the other half. The handle had to be within the instantaneous target's digitizer-defined boundaries for the latter to keep moving. All tracking movements were segmented into small movement steps. A tendency to outrun the target was seen, indicating predictive control. Absence of visual feedback had negligible effect on movement velocity. Movement direction appeared to involve open-loop programming but improved significantly when subjects could see the cursor. Occasional corrective movements occurred only when visual feedback was given. Otherwise, a large positional error accumulates despite reasonable ability to control tracking direction.

Dilated cardiomyopathy and sensorineural hearing loss: a heritable syndrome that maps to 6q23-24

BACKGROUND

Dilated cardiomyopathy (DCM) and sensorineural hearing loss (SNHL) are prevalent disorders that occur alone or as components of complex multisystem syndromes. Multiple genetic loci have been identified that, when mutated, cause DCM or SNHL. However, the isolated coinheritance of these phenotypes has not been previously recognized.

METHODS AND RESULTS

Clinical evaluations of 2 kindreds demonstrated autosomal-dominant transmission and age-related penetrance of both SNHL and DCM in the absence of other disorders. Moderate-to-severe hearing loss was evident by late adolescence, whereas ventricular dysfunction produced progressive congestive heart failure after the fourth decade. DNA samples from the larger kindred (29 individuals) were used to perform a genome-wide linkage study. Polymorphic loci on chromosome 6q23 to 24 were coinherited with the disease (maximum logarithm of odds score, 4.88 at locus D6S2411). The disease locus must lie within a 2.8 cM interval between loci D6S975 and D6S292, a location that overlaps an SNHL disease locus (DFNA10). However, DFNA10 does not cause cardiomyopathy. The epicardin gene, which encodes a transcription factor expressed in the myocardium and cochlea, was assessed as a candidate gene by nucleotide sequence analysis; no mutations were identified.

CONCLUSIONS

A syndrome of juvenile-onset SNHL and adult-onset DCM is caused by a mutation at 6q23 to 24 (locus designated CMD1J). Recognition of this cardioauditory disorder allows for the identification of young adults at risk for serious heart disease, thereby enabling early intervention. Definition of the molecular cause of this syndrome may provide new information about important cell physiology common to both the ear and heart.

Data watch: research data in health economics

In this paper, we discuss some important data sets that can be used by economists interested in conducting research in health economics. We describe six types of data sets: health components of data sets traditionally used by economists; longitudinal surveys of health and economic behavior; data on employer-provided insurance; cross-sectional surveys of households that focus on health; data on health care providers; and vital statistics. We summarize some of the leading surveys, discuss the availability of the data, identify how researchers have utilized these data and when possible, include a web address that contains more detailed information about each survey.

Recent trends in employer-sponsored health insurance coverage: are bad jobs getting worse?

We examine whether the decline in the availability of employer-provided health insurance is a phenomenon common to all jobs or is concentrated only on certain jobs. We find that declines in own-employer insurance coverage over the 1988-1997 period are driven primarily by declines in take-up for long-term full-time workers and declines in eligibility for new and part-time workers. We also look at trends by workers' education level, and see how much of the decline in is offset by an increase in coverage through a spouse's policy.

Maternal phenylketonuria syndrome: congenital heart defects, microcephaly, and developmental outcomes

OBJECTIVE

A cohort of women with phenylketonuria (PKU) were selected to explore the impact of phenylalanine (Phe) levels and other factors on congenital heart defects (CHDs), microcephaly, and development of their offspring.

STUDY DESIGN

Three hundred fifty-four women with PKU were followed up weekly with diet records, blood Phe levels, and sonograms obtained at 18 to 20 and 32 weeks' gestation. At birth, 413 offspring were examined and followed up at 6 months and annually by means of Bayley Mental Developmental Index and Psychomotor Developmental Index tests at 1 and 2 years. The women had Wechsler Adult Intelligence Scales and DNA testing.

RESULTS

Thirty-one offspring had CHDs; of these, 17 also had microcephaly. Mean Phe levels at 4 to 8 weeks' gestation predicted CHDs (P <.0001). An infant with a CHD had a 3-fold risk of having microcephaly when the mother had higher Phe levels (P =.02). The Bayley Mental Developmental Index and Psychomotor Developmental Index scores correlated with both CHDs (P =.037 and.0015, respectively) and microcephaly (P =.0001 for both). No direct relationship to the PKU mutation was found.

CONCLUSION

None of the women whose offspring had CHDs had blood Phe levels in control during the first 8 weeks of gestation. Women with PKU need to be well controlled on a low-phenylalanine diet before conception and throughout pregnancy.

Target and specificity of a nuclear gene product that participates in mRNA 3'-end formation in Chlamydomonas chloroplasts

Chloroplast mRNA maturation is catalyzed by nucleus-encoded processing enzymes. We previously described a recessive nuclear mutation (crp3) that affects 3'-end formation of several chloroplast mRNAs in Chlamydomonas reinhardtii (Levy, H., Kindle, K. L., and Stern, D. B. (1997) Plant Cell 9, 825-836). In the crp3 background, atpB mRNA lacking a 3'-inverted repeat normally required for stability accumulates as a discrete transcript. The mutation also affects the atpA gene cluster; polycistronic mRNAs with psbI or cemA 3'-ends accumulate to a lower level in the crp3 background. Here, we demonstrate that the crp3 mutation also alters 3'-end formation of psbI mRNA and cemA-containing mRNAs. A novel 3'-end is formed in monocistronic psbI transcripts, and this is the only terminus observed when the psbI 3'-untranslated region is fused to an aadA reporter gene. Accumulation of mRNAs with 3'-ends between cemA and atpH, which is immediately downstream, was reduced. However, this sequence was not recognized as a 3'-end formation element in chimeric genes. The crp3 mutation was able to confer stability to three different atpB 3'-stem-loop-disrupting mutations that lack sequence similarity, but are located at a similar distance from the translation termination codon. We propose that the wild-type CRP3 gene product is part of the general 3' --> 5' processing machinery.

Liposomal prostaglandin E1 (TLC C-53) in acute respiratory distress syndrome: a controlled, randomized, double-blind, multicenter clinical trial. TLC C-53 ARDS Study Group

OBJECTIVE

To evaluate the safety and efficacy of an intravenous liposomal dispersion of prostaglandin E1 as TLC C-53 in the treatment of patients with acute respiratory distress syndrome (ARDS).

DESIGN

Randomized, prospective, multicenter, double-blind, placebo-controlled, phase III clinical trial.

SETTING

Forty-seven community and university-affiliated hospitals in the United States.

PATIENTS

A total of 350 patients with ARDS were enrolled in this clinical trial.

INTERVENTION

Patients were prospectively randomized in a 1:1 ratio to receive either liposomal prostaglandin E1 or placebo. The study drug was infused intravenously for 60 mins every 6 hrs for 7 days starting with a dosage of 0.15 microg/kg/hr. The dose was increased every 12 hrs until the maximal dose (3.6 microg/kg/hr) was attained or intolerance to further increases developed. Patients received standard aggressive medical/surgical care during the infusion period.

OUTCOME MEASURES

The primary outcome measure was the time it took to wean the patient from the ventilator. Secondary end points included time to improvement of the PaO2/FIO2 ratio (defined as first PaO2/FIO2 > 300 mm Hg), day 28 mortality, ventilator dependence at day 8, changes in PaO2/FIO2, incidence of and time to development/resolution of organ failure other than ARDS.

RESULTS

A total of 348 patients could be evaluated for efficacy. The distribution of variables at baseline describing gender, lung injury scores, Acute Physiology and Chronic Health Evaluation II scores, PaO2/FIO2, pulmonary compliance, and time from onset of ARDS or from institution of mechanical ventilation to the first dose of study drug was similar among patients in the liposomal prostaglandin E1 (n = 177) and the placebo (n = 171) treatment arms. There was no significant difference in the number of days to the discontinuation of ventilation in the liposomal prostaglandin E1 group compared with the placebo group (median number of days to off mechanical ventilation, 16.9 in patients receiving liposomal prostaglandin E1 and 19.6 in those administered placebo; p = .94). Similarly, mortality at day 28 was not significantly different in the two groups (day 28 mortality, 57 of 176 (32%) in the liposomal prostaglandin E1 group and 50 of 170 (29%) in patients receiving placebo; p = .55). In contrast, treatment with liposomal prostaglandin E1 was associated with a significantly shorter time to reach a PaO2/FIO2 ratio of >300 mm Hg (median number of days to reaching a PaO2/FIO2 ratio >300 mm Hg: 9.8 days in the liposomal prostaglandin E1 group and 13.7 days in patients receiving the placebo; p = .02). Among the subgroups examined, time to off mechanical ventilation was significantly reduced in patients who received at least 85% of a full dose (i.e., > 45.9 microg/kg) of liposomal prostaglandin E1 (median number of days to discontinuation of ventilation, 10.3 in the liposomal prostaglandin E1 group and 16.3 days in patients receiving placebo; p = .05). The overall incidence of serious adverse events was not significantly different in the liposomal prostaglandin E1 (40%) or placebo-treated (37%) groups. Drug-related adverse events of all kinds were reported in 69% of the patients receiving liposomal prostaglandin E1 compared with 33% of the placebo group, with hypotension and hypoxia (occurring in 52% and 24% of the liposomal prostaglandin E1-treated patients, respectively, and 17% and 5% of the placebo-treated patients, respectively) being noted most frequently.

CONCLUSIONS

In the intent-to-treat population of patients with ARDS, treatment with liposomal prostaglandin E1 accelerated improvement in indexes of oxygenation but did not decrease the duration of mechanical ventilation and did not improve day 28 survival.