Measure what matters: considerations for outcome measurement of care coordination for children with neurodevelopmental disabilities and medical complexity

Introduction

Care Coordination (CC) is a significant intervention to enhance family's capacity in caring for children with neurodevelopmental disability and medical complexity (NDD-MC). CC assists with integration of medical and behavioral care and services, partnerships with medical and community-based supports, and access to medical, behavioral, and educational supports and services. Although there is some consensus on the principles that characterize optimal CC for children with NDD-MC, challenges remain in measuring and quantifying the impacts of CC related to these principles. Two key challenges include: (1) identification of measures that capture CC impacts from the medical system, care provider, and family perspectives; and (2) recognition of the important community context outside of a hospital or clinical setting.

Methods

This study used a multilevel model variant of the triangulation mixed methods design to assess the impact of a CC project implemented in Alberta, Canada, on family quality of life, resource use, and care integration at the broader environmental and household levels. At the broader environmental level, we used linked administrative data. At the household level we used quantitative pre-post survey datasets, and aggregate findings from qualitative interviews to measure group-level impacts and an embedded multiple-case design to draw comparisons, capture the nuances of children with NDD-MC and their families, and expand on factors driving the high variability in outcome measures. Three theoretical propositions formed the basis of the analytical strategy for our case study evidence to explore factors affecting the high variability in outcome measures.

Discussion

This study expanded on the factors used to measure the outcomes of CC and adds to our understanding of how CC as an intervention impacts resource use, quality of life, and care integration of children with NDD-MC and their families. Given the heterogeneous nature of this population, evaluation studies that account for the variable and multi-level impacts of CC interventions are critical to inform practice, implementation, and policy of CC for children with NDD-MC.

Hyperhydration to Improve Kidney Outcomes in Children with Shiga Toxin-Producing E. coli Infection: a multinational embedded cluster crossover randomized trial (the HIKO STEC trial)

BACKGROUND

Shiga toxin-producing E. coli (STEC) infections affect children and adults worldwide, and treatment remain solely supportive. Up to 15-20% of children infected by high-risk STEC (i.e., E. coli that produce Shiga toxin 2) develop hemolytic anemia, thrombocytopenia, and kidney failure (i.e., hemolytic uremic syndrome (HUS)), over half of whom require acute dialysis and 3% die. Although no therapy is widely accepted as being able to prevent the development of HUS and its complications, several observational studies suggest that intravascular volume expansion (hyperhydration) may prevent end organ damage. A randomized trial is needed to confirm or refute this hypothesis.

METHODS

We will conduct a pragmatic, embedded, cluster-randomized, crossover trial in 26 pediatric institutions to determine if hyperhydration, compared to conservative fluid management, improves outcomes in 1040 children with high-risk STEC infections. The primary outcome is major adverse kidney events within 30 days (MAKE30), a composite measure that includes death, initiation of new renal replacement therapy, or persistent kidney dysfunction. Secondary outcomes include life-threatening, extrarenal complications, and development of HUS. Pathway eligible children will be treated per institutional allocation to each pathway. In the hyperhydration pathway, all eligible children are hospitalized and administered 200% maintenance balanced crystalloid fluids up to targets of 10% weight gain and 20% reduction in hematocrit. Sites in the conservative fluid management pathway manage children as in- or outpatients, based on clinician preference, with the pathway focused on close laboratory monitoring, and maintenance of euvolemia. Based on historical data, we estimate that 10% of children in our conservative fluid management pathway will experience the primary outcome. With 26 clusters enrolling a mean of 40 patients each with an intraclass correlation coefficient of 0.11, we will have 90% power to detect a 5% absolute risk reduction.

DISCUSSION

HUS is a devastating illness with no treatment options. This pragmatic study will determine if hyperhydration can reduce morbidity associated with HUS in children with high-risk STEC infection.

TRIAL REGISTRATION

ClinicalTrials.gov NCT05219110 . Registered on February 1, 2022.

Atmospheric implications of large C2-C5 alkane emissions from the U.S. oil and gas industry

Emissions of C₂-C₅ alkanes from the U.S. oil and gas sector have changed rapidly over the last decade. We use a nested GEOS-Chem simulation driven by updated 2011NEI emissions with aircraft, surface and column observations to 1) examine spatial patterns in the emissions and observed atmospheric abundances of C₂-C₅ alkanes over the U.S., and 2) estimate the contribution of emissions from the U.S. oil and gas industry to these patterns. The oil and gas sector in the updated 2011NEI contributes over 80% of the total U.S. emissions of ethane (C₂H₆) and propane (C₃H₈), and emissions of these species are largest in the central U.S. Observed mixing ratios of C₂-C₅ alkanes show enhancements over the central U.S. below 2 km. A nested GEOS-Chem simulation underpredicts observed C₃H₈ mixing ratios in the boundary layer over several U.S. regions and the relative underprediction is not consistent, suggesting C₃H₈ emissions should receive more attention moving forward. Our decision to consider only C₄-C₅ alkane emissions as a single lumped species produces a geographic distribution similar to observations. Due to the increasing importance of oil and gas emissions in the U.S., we recommend continued support of existing long-term measurements of C₂-C₅ alkanes. We suggest additional monitoring of C₂-C₅ alkanes downwind of northeastern Colorado, Wyoming and western North Dakota to capture changes in these regions. The atmospheric chemistry modeling community should also evaluate whether chemical mechanisms that lump larger alkanes are sufficient to understand air quality issues in regions with large emissions of these species.

Endothelial abnormalities in adolescents with type 1 diabetes: a biomarker for vascular sequelae?

OBJECTIVE

To evaluate whether counts of circulating colony forming unit-endothelial cells (CFU-ECs), cells co-expressing CD34, CD133, and CD31 (CD34+CD133+CD31+), and CD34+CD45- cells are altered in adolescents with type 1 diabetes and if the changes in counts correlate with endothelial dysfunction.

STUDY DESIGN

Adolescents with diabetes (ages 18 to 22 years) and race- and sex-matched control subjects were studied. We assessed circulating CFU-ECs, using colony assays, and CD34+CD133+CD31+ and CD34+CD45- cells, using poly-chromatic flow cytometry. CFU-ECs and CD34+CD133+CD31+ are hematopoietic-derived progenitors that inversely correlate with cardiovascular risk in adults. CD34+CD45- cells are enriched for endothelial cells with robust vasculogenic potential. Vascular reactivity was tested by laser Doppler iontophoresis.

RESULTS

Subjects with diabetes had lower CD34+CD133+CD31+ cells, a trend toward reduced CFU-ECs, and increased CD34+CD45- cells compared with control subjects. Endothelium-dependent vasodilation was impaired in subjects with diabetes, which correlated with reductions in circulating CD34+CD133+CD31+ cells.

CONCLUSIONS

Long-term sequelae of type 1 diabetes include vasculopathies. Endothelial progenitor cells promote vascular health by facilitating endothelial integrity and function. Lower CD34+CD133+CD31+ cells may be a harbinger of future macrovascular disease risk. Higher circulating CD34+CD45- cells may reflect ongoing endothelial damage. These cells are potential biomarkers to guide therapeutic interventions to enhance endothelial function and to prevent progression to overt vascular disease.

An Exploratory Study of the Biological Activity of Sunitinib as a Component of Neoadjuvant Therapy for Breast Cancer

Background: The neoadjuvant setting provides an ideal opportunity to explore the impact of sunitinib alone and in combination with paclitaxel on the functional status of tumor vasculature as indicated by changes in tumor interstitial pressure (IFP) and circulating progenitor cell (CPC) subsets.Methods: Patients(pts.) with newly diagnosed stage Ic-IIIc breast cancer were treated with sunitinib monotherapy (100 mg Day 1; 37.5 mg D2-14) prior to the initiation of paclitaxel (80 mg/M2 D1,8,15 every 28 days x 4 cycles) with sunitinib (25 mg/d). IFP and CPC subsets were assessed at baseline and after sunitinib monotherapy. IFP was measured in three separate areas of the tumor using a micropressure transducer catheter; mean and highest IFP recorded were analyzed. Improvements in poly-chromatic flow cytometry allowed distinction of pro-angiogenic (pCPC = Live/AC133+CD34bright/CD31+CD45dim\), from non-angiogenic (nCPC = Live/AC133-CD34bright/CD31+/CD45dim\), CPCs that cannot be quantified separately using previously reported protocols1. Baseline CPC subsets were also compared to age and gender matched healthy controls.Results: From July 2008 to May 2009, 14 pts were enrolled; baseline and post-sunitinib IFP and CPC data are available for 12 and 11 pts respectively. The median age was 48 (range 32-69). Mean pretreatment tumor diameter was 3.2 cm. Sunitinib monotherapy was generally well tolerated; two patients developed grade III toxicities including hypertension (n=1) and hand-foot syndrome (n=1). Sunitinib significantly decreased mean IFP (18.87 mmHg vs. 6.38 mmHg; p=0.002); similar results were obtained when only the maximum IFP was considered (22.32 mmHg vs. 8.36 mmHg; p=0.003). pCPC frequency was not different between pts and healthy controls (0.099% vs. 0.076%, p=0.24) but the p:nCPC ratio was significantly higher in pts compared to healthy controls (3.26 vs. 1.46; p=0.001) suggesting a shift toward vascular damage and/or active angiogenesis. Both pCPC frequency (0.099 vs. 0.022; p=0.001) and p:nCPC ratio (3.26 vs. 0.78; p=0.001) significantly decreased after sunitinib monotherapy. Analysis of paclitaxel + sunitinib is too early (n=4).Conclusion: Sunitinib, through its effects on VEGF-mediated vascular permeability, markedly reduces tumor IFP. In addition sunitinib profoundly reduces pCPCs that are thought to be important for angiogenesis in human cancers. Accrual is ongoing (planned N=40). Analysis of IFP and CPC subsets after paclitaxel + sunitinib as well as additional correlates will be presented.1 Duda et al. (2007). Nat. Protocol 2, 805-810.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 202.

Inhibition of p38alpha MAPK disrupts the pathological loop of proinflammatory factor production in the myelodysplastic syndrome bone marrow microenvironment

Myelodysplastic syndromes (MDS) are common causes of ineffective hematopoiesis and cytopenias in the elderly. Various myelosuppressive and proinflammatory cytokines have been implicated in the high rates of apoptosis and hematopoietic suppression seen in MDS. We have previously shown that p38 MAPK is overactivated in MDS hematopoietic progenitors, which led to current clinical studies of the selective p38alpha inhibitor, SCIO-469, in this disease. We now demonstrate that the myelosuppressive cytokines TNFalpha and IL-1beta are secreted by bone marrow (BM) cells in a p38 MAPK-dependent manner. Their secretion is stimulated by paracrine interactions between BM stromal and mononuclear cells and cytokine induction correlates with CD34+ stem cell apoptosis in an inflammation-simulated in vitro bone marrow microenvironment. Treatment with SCIO-469 inhibits TNF secretion in primary MDS bone marrow cells and protects cytogenetically normal progenitors from apoptosis ex vivo. Furthermore, p38 inhibition diminishes the expression of TNFalpha or IL-1beta-induced proinflammatory chemokines in BM stromal cells. These data indicate that p38 inhibition has anti-inflammatory effects on the bone marrow microenvironment that complements its cytoprotective effect on progenitor survival. These findings support clinical investigation of p38alpha as a potential therapeutic target in MDS and other related diseases characterised by inflammatory bone marrow failure.

In vitro hyperglycemia or a diabetic intrauterine environment reduces neonatal endothelial colony-forming cell numbers and function

OBJECTIVE

Emerging data demonstrate that maternal diabetes has long-term health consequences for offspring, including the development of hypertension. In adults, circulating endothelial progenitor cells (EPCs) participate in vascular repair, and EPC numbers and function inversely correlate with the risk of developing vascular disease. Therefore, our objectives were to determine whether hyperglycemia or exposure to a diabetic intrauterine environment alters EPC function.

RESEARCH DESIGN AND METHODS

We used well-established clonogenic endothelial colony-forming cell (ECFC) assays and murine transplantation experiments to examine human vasculogenesis.

RESULTS

Both in vitro hyperglycemia and a diabetic intrauterine environment reduced ECFC colony formation, self-renewal capacity, and capillary-like tube formation in matrigel. This cellular phenotype was linked to premature senescence and reduced proliferation. Further, cord blood ECFCs from diabetic pregnancies formed fewer chimeric vessels de novo after transplantation into immunodeficient mice compared with neonatal ECFCs harvested from uncomplicated pregnancies. CONCLUSIONS; Collectively, these data demonstrate that hyperglycemia or exposure to a diabetic intrauterine environment diminishes neonatal ECFC function both in vitro and in vivo, providing potential mechanistic insights into the long-term cardiovascular complications observed in newborns of diabetic pregnancies.

Inhibition of overactivated p38 MAPK can restore hematopoiesis in myelodysplastic syndrome progenitors

The myelodysplastic syndromes (MDSs) are collections of heterogeneous hematologic diseases characterized by refractory cytopenias as a result of ineffective hematopoiesis. Development of effective treatments has been impeded by limited insights into any unifying pathogenic pathways. We provide evidence that the p38 MAP kinase is constitutively activated or phosphorylated in MDS bone marrows. Such activation is uniformly observed in varied morphologic subtypes of low-risk MDS and correlates with enhanced apoptosis observed in MDS hematopoietic progenitors. Most importantly, pharmacologic inhibition of p38alpha by a novel small molecule inhibitor, SCIO-469, decreases apoptosis in MDS CD34+ progenitors and leads to dose-dependant increases in erythroid and myeloid colony formation. Down-regulation of the dominant p38alpha isoform by siRNA also leads to enhancement of hematopoiesis in MDS bone marrow progenitors in vitro. These data implicate p38 MAPK in the pathobiology of ineffective hematopoiesis in lowrisk MDS and provide a strong rationale for clinical investigation of SCIO-469 in MDS.

Jail inmates and HIV care: provision of antiretroviral therapy and Pneumocystis carinii pneumonia prophylaxis

The objective of this study was to examine prescription and acceptance of antiretroviral therapy (ART) and Pneumocystis carinii pneumonia (PCP) prophylaxis in jail and at release. A retrospective cross sectional design was used, by record review, of 77 inmates receiving HIV-related care in the San Francisco City and County Jail and released to the community in 1997. Average CD4 cell count was 335/microl. Fifteen had undectable HIV RNA, and average viral load was 19,826 copies/ml. Fifty-eight per cent were put on ART in jail. Lower CD4 cell count was associated with ART (P=0.017). All inmates with CD4 cell counts less than 200/microl received PCP prophylaxis. According to 1996 guidelines, 72% of those eligible for ART were on therapy. Of 24 inmates released on ART, 71% followed medical advice and picked up medication at release. HIV care in the San Francisco Jail met high standards and exceeded levels reported in other populations.

ECG Findings in Active Patients: Differentiating the Benign From the Serious

ECGs and cardiac rhythms of normal athletes can vary widely. The heightened vagal tone from athletic conditioning can result in variant ECG findings that may mimic serious disorders. ECG patterns of long-QT syndrome, arrhythmogenic right ventricular dysplasia, Wolff-Parkinson-White syndrome, and hypertrophic cardiomyopathy signal the need for further evaluation, therapy, and possible participation restriction. Radiofrequency ablation may be appropriate when symptomatic supraventricular arrhythmias or Wolff-Parkinson-White syndrome is present. Further research is needed to effectively distinguish normal ECG changes in the athlete from changes that underlie cardiac disease. Improvements in identifying athletes at risk of serious or life-threatening arrhythmias are also needed.

Distinct epidemiological patterns of Norwalk-like virus infection

Norwalk-like viruses (NLV) are important economically as a cause of both sporadic gastroenteritis in the community and large outbreaks in hospitals and other institutional settings. Despite the description of several antigenic types relatively little is known about the epidemiology of these individual types. NLVs were detected by electron microscopy in faecal specimens from 706 outbreaks of gastroenteritis that represented 68% of all outbreaks of non-bacterial gastroenteritis. These outbreaks took place in the counties of West and North Yorkshire and Humberside during six winter seasons between July 1992 and June 1998. NLV strains from 671 outbreaks were typed by antigen capture enzyme linked immunosorbent assays (ELISA) based on antisera made to recombinant virus-like particles of three antigenically distinct NLVs; Norwalk (NV), Mexico (MXV) and Grimsby (GRV) viruses. GRV was the predominant strain for five of the six winter seasons and overall was associated with 61% of NLV outbreaks. MXV was responsible for a single epidemic peak in the winter of 1993/94 but was also observed at other times throughout the study period. NV was only associated with two outbreaks in 1994 that were epidemiologically linked. Strains from the remaining 32% of outbreaks were non-reactive in all three ELISA. Thus, a single NLV antigenic type seems to have predominated during the period 1992 to 1998 in the UK.

Defibrillators in nonischemic cardiomyopathy treatment evaluation

The Defibrillators in Nonischemic Cardiomyopathy Treatment Evaluation (DEFINITE) is a multicenter randomized trial. Patients will have nonischemic cardiomyopathy (LVEF < or = 35%), a history of symptomatic heart failure and spontaneous arrhythmia (> 10 PVCs/hour or nonsustained ventricular tachycardia defined as 3-15 beats at a rate of > 120 beats/min) on Holter monitor or telemetry within the past 6 months. Patients will be randomized to an implantable cardioverter defibrillator (ICD) versus no ICD. All patients will receive standard oral medical therapy for heart failure including angiotensin converting enzyme inhibitors and beta-blockers (if tolerated). Patients will be followed for 2-3 years. The primary endpoint will be total mortality. Quality-of-life and pharmacoeconomics analyses will also be performed. A registry will track patients who meet basic inclusion criteria but are not randomized. We estimate an annual total mortality of 15% at 2 years in the treatment arm that does not receive an ICD. The ICD is expected to reduce mortality by 50%. Approximately 204 patients will be required in each treatment group. Twenty-five centers will be included in a trial designed to last an estimated 4 years.

Humoral and cell-mediated immune responses in humans to the NSP4 enterotoxin of rotavirus

Rotavirus nonstructural protein NSP4 has recently been suggested to function as a viral enterotoxin and play a role in the pathophysiological mechanism whereby rotaviruses induce diarrhea. The ability of rotavirus NSP4 to stimulate a humoral immune response was examined in naturally infected children and adults, rotavirus vaccinated children, as well as a cellular immune response in adults. In this study, 10 of 10 naturally infected children and 9 of 10 rotavirus-vaccinated children showed a weak humoral IgG immune response to recombinant NSP4 (rNSP4) and/or a synthetic peptide corresponding to residues 114-134 of NSP4. Modest serum IgG antibody responses were detected in 20 of 20 adults. A cellular immune response to rNSP4 and/or NSP4(114-134) were detected in 8 of 10 adults measured either as a T-cell proliferative response (7 of 10), an increased production of IL-2 (6 of 10), or increased production of interferon-gamma (8 of 10). These results indicate that NSP4 induces a humoral immune response in humans and show for the first time that NSP4 stimulates a cellular immune response, possibly including cytolytic T-cells.

Correlation waveform analysis to discriminate monomorphic ventricular tachycardia from sinus rhythm using stored electrograms from implantable defibrillators

In order to examine whether a template-matching program utilizing correlation waveform analysis (CWA) might be used to discriminate monomorphic ventricular tachycardia (MMVT) from sinus rhythm (SR) in patients with implantable cardioverter defibrillators (ICDs), we studied stored episodes of induced MMVT in 25 patients and compared them to corresponding stored SR electrograms. We calculated mean correlation coefficients for SR beats against an SR template chosen within each sinus episode, induced MMVT beats against an induced MMVT template within each ventricular tachycardia episode, and induced MMVT beats against the original SR template. For each patient, the 99.5% lower confidence limit for the mean correlation coefficient of SR beats versus an SR template (patient-specific method) or the empirical correlation coefficient value 0.9 were selected as threshold values to discriminate induced MMVT from SR. The mean correlation coefficient for induced MMVT beats versus the original SR template for each patient was subtracted from both threshold values. A positive value is defined as accurate discrimination of induced MMVT from SR. Using 0.9 for a threshold cut off, 21 of 25 episodes of induced MMVT were accurately labeled with a sensitivity of 84%. Using the patient-specific method, we were able to correctly distinguish 23 of 25 episodes of induced MMVT from SR with a sensitivity of 92%. There was no statistically significant difference between the patient-specific or empirical methods in detecting MMVT (P 50.4). This is the first demonstration using stored intracardiac electrograms from ICDs that CWA is able to discriminate MMVT from SR with high sensitivity. Such a template-matching system may be used for off-line analysis or real-time rhythm discrimination.

Analysis of ankle deflection during a forward fall in snowboarding

Toward the general goal of preventing ankle injuries in snowboarding accidents, the objective of this project to develop a dynamic system model of a snowboarder and assess which model parameters, particularly those attributed to the boot, most strongly influenced ankle deflections during a forward fall. To satisfy this objective, a system model was created that included the rider, the boots, the snowboard, and the snow as components. Through dynamic simulations, peak ankle deflections were computed over realistic ranges of input parameter values for each of the model components. Defining sensitivity as the total change in peak ankle deflection over the range of a particular parameter studied, results indicated that the peak ankle deflection was most sensitive to the boot stiffness. Although lower, the sensitivity of the peak ankle deflection to the snow model parameters was still significant, being roughly half of the boot sensitivity. Increases in both snow stiffness and snow damping caused higher ankle deflections. Variations in both snowboard stiffness and anthropometric parameters had little effect. Due to the strong dependence of ankle deflection on boot stiffness, the potential exists for mitigating the ankle injury problem through judicious design of the boot.

Interference with cardiac pacemakers by cellular telephones

BACKGROUND

A growing body of evidence suggests that electromagnetic interference may occur between cardiac pacemakers and wireless hand-held (cellular) telephones, posing a potential public health problem. Electromagnetic interference may occur when the pacemaker is exposed to an electromagnetic field generated by the cellular telephone.

METHODS

In this multicenter, prospective, crossover study, we tested 980 patients with cardiac pacemakers with five types of telephones (one analogue and four digital) to assess the potential for interference. Telephones were tested in a test mode and were programmed to transmit at the maximal power, simulating the worst-case scenario; in addition, one telephone was tested during actual transmission to simulate actual use. Patients were electrocardiographically monitored while the telephones were tested at the ipsilateral ear and in a series of maneuvers directly over the pacemaker. Interference was classified according to the type and clinical significance of the effect.

RESULTS

The incidence of any type of interference was 20 percent in the 5533 tests, and the incidence of symptoms was 7.2 percent. The incidence of clinically significant interference was 6.6 percent. There was no clinically significant interference when the telephone was placed in the normal position over the ear. Interference that was definitely clinically significant occurred in only 1.7 percent of tests, and only when the telephone was held over the pacemaker. Interference was more frequent with dual-chamber pacemakers (25.3 percent) than with single-chamber pacemakers (6.8 percent, P<0.001) and more frequent with pacemakers without feed-through filters (28.9 to 55.8 percent) than with those with such filters (0.4 to 0.8 percent, P=0.01).

CONCLUSIONS

Cellular telephones can interfere with the function of implanted cardiac pacemakers. However, when telephones are placed over the ear, the normal position, this interference does not pose a health risk.

Transthyretin amyloidosis: a new mutation associated with dementia

Familial transthyretin (TTR) amyloidosis commonly presents with peripheral neuropathy and involvement of visceral organs. In contrast, signs of central nervous system (CNS) involvement are exceptional. We report that members of a kindred affected by a slowly progressive dementia, seizures, ataxia, hemiparesis, and decreased vision without neuropathy have TTR amyloid deposits in the leptomeninges, the brain parenchyma, and the eye. This condition, previously labeled oculoleptomeningeal amyloidosis, is linked to a mutation at codon 30 of TTR gene, resulting in the substitution of valine with glycine in this family, TTR amyloid deposits were present in the leptomeninges, especially the leptomeningeal vessels, and in the subependymal regions of the ventricular system where they disrupted the ependymal lining and resulted in amyloid-glial formations protruding into and narrowing the ventricular system. Hydrocephalus and atrophy and infarction of cerebral and cerebellar cortexes were also present. Review of the literature shows that amyloid deposition in the leptomeninges is not uncommon in TTR amyloidoses clinically characterized by peripheral neuropathy and lack of CNS signs. The present kindred, which presented exclusively with signs of CNS involvement, expands the phenotype of TTR amyloidosis and raises questions concerning the mechanisms determining phenotypic expression in TTR familial amyloidosis.

Pharmacokinetics and cardiovascular effects of ma-huang (Ephedra sinica) in normotensive adults

The purpose of this study was to evaluate heart rate and blood pressure responses to a commercially available source of ma-haung, a natural source of the sympathomimetic substance, ephedrine, and to evaluate the pharmacokinetic properties of the product in normotensive, healthy adults. On day 1, twelve study participants were monitored with an ambulatory blood pressure device between hours 7 and 20. On day 2, they ingested four capsules of powdered ma-huang at hours 8 and 17 while again wearing the monitor between hours 7 and 20. Serial plasma samples were obtained and concentrations of ephedrine were analyzed by high-performance liquid chromatography. Pharmacokinetic parameters of ephedrine were determined from plasma concentration-time profiles. The ephedrine alkaloid content of each capsule was also determined by high-performance liquid chromatography. Six participants experienced a statistically significant increase in heart rate, but the effects on blood pressure were variable. The half-life, volume of distribution, clearance, and maximum concentration in plasma of ephedrine in the ma-huang product were similar to values previously reported for a 20 mg, immediate-release ephedrine tablet. Values for the absorption rate were considerably lower and time to reach maximum concentration was longer for the capsules, compared with the standard tablet. Variability in alkaloid content of ephedrine was low and yielded a mean dose of ephedrine at 19.4 mg; pseudoephedrine at 4.9 mg; and methylephedrine at 1.2 mg for a four-capsule dose. In summary, ma-haung had variable effects on blood pressure and increased heart rate in healthy, normotensive adults. Pharmacokinetic parameters for ephedrine were in agreement with those previously reported; however, the absorption rate was much slower after ingestion of ma-huang.

Extrahepatic ischemia-reperfusion injury reduces hepatic oxidative drug metabolism as determined by serial antipyrine clearance

PURPOSE

All transplanted solid organs experience some degree of ischemia-reperfusion (I-R) injury. This I-R injury can contribute to graft dysfunction which stems in part from the acute phase response and a resultant host of cytokines. Recent evidence suggests that organs remote to the site of I-R injury can be affected by circulating cytokines originating from these I-R injuries. Since many of these acute phase cytokines inhibit hepatic cytochrome P-450 (CYP) enzymes, we chose to investigate whether extrahepatic I-R injuries could influence hepatic oxidative drug metabolism.

METHODS

Fifteen dogs were divided into three surgical groups: (I) sham I-R; (II) bilateral normothermic renal I-R; and (III) normothermic intestinal I-R. Antipyrine (AP) was selected as a model substrate and administered intravenously at a dose of 10 mg/kg. AP serum concentrations were determined by HPLC and cytokine activity (IL-1, IL-6, and TNFalpha) was measured via bioassay. Serial AP clearance and serum cytokine concentrations were determined 3 days prior to and at 4 hr, 24 hr, 3 days and 7 days after surgery. Hematology and blood chemistries were monitored throughout the study period.

RESULTS

AP clearance was significantly reduced in groups II and III at 4 and 24 hrs post-l-R injury, while AP binding and apparent volume of distribution were unaffected. Peak levels of TNF and IL-6 activity occurred at 1 and 4 hours, respectively. IL-I activity was not detected in any group. AP clearance correlated strongly to circulating levels of IL-6 (r = -0.789, p = 0.0002).

CONCLUSIONS

Our findings indicate that extrahepatic I-R injury can affect hepatic oxidative drug metabolism and this effect is mediated in part by circulating cytokines.

Prevalence of serum antibodies to Norwalk virus among Norwegian military recruits

The prevalence of serum antibodies against Norwalk virus among military recruits in Norway was investigated using an enzyme-linked immunosorbent assay (ELISA). A total of 1017 sera were assayed for anti-Norwalk virus total antibodies (ig), of which 300 (29.5%) were positive. Of 227 positive sera, 10.6 and 15.4% were positive for IgA and IgM, respectively, while 2.2% were positive for both. The prevalence of antibodies against Norwalk virus in south-east Norway was significantly higher than that in northern Norway.

Mirror focus: function of seizure frequency and influence on outcome after surgery

The concept of the mirror focus (MF) implies that an actively discharging epileptiform region may induce similar paroxysmal behavior in a homologous site. In a group of patients with complex partial seizures (CPS) we investigated whether occurrence of a MF was influenced by certain clinical factors and whether surgical outcome was influenced by the presence of an MF. Factors studied included age at onset, duration, and total number of seizures. Patients had had CPS for > 3 years and had pathologically proven temporal lobe neoplasms. Seizure frequency was estimated by the history-taking physician. We estimated total seizure number by multiplying frequency by duration. Seven patients had MF, and 15 did not. Mean age at onset of seizures, duration of seizure disorder, and total seizure number did not vary statistically between the two groups of patients. All patients with an MF except 1 were seizure-free at follow-up. Ten of the 15 patients without MF were seizure-free. Three patients who were not seizure-free had had subtotal resection owing to tumor overlap with eloquent cortex. We conclude that an MF is not a contraindication to operation even when the preponderance of interictal spike activity is contralateral to the tumor or when seizures appear to arise from the MF on scalp EEG.

Efficacy of a recombinant Norwalk virus protein enzyme immunoassay for the diagnosis of infections with Norwalk virus and other human "candidate" caliciviruses

A recombinant Norwalk virus antigen enzyme immunoassay (rNV EIA) for the detection fo Norwalk virus (NV) antibodies was evaluated using sera from volunteers and patients infected with Norwalk, Hawaii, Snow Mountain Agent, small round structured viruses (SRSV), and human calicivirus (HuCV) strains. The results for NV antibodies correlated well with previous results obtained using a NV radioimmunoassay. The test rNV EIA was found to be highly specific for NV. The results of tests on sera obtained from patients involved in confirmed outbreaks of SRSV in the UK showed that only 1/12 was due to Norwalk virus. Further evidence is presented that SRSV strain UK2 is antigenically related to NV.

Temporal lobe epilepsy in early childhood

To explore the electroclinical features of temporal lobe epilepsy (TLE) in early childhood, we studied results of video-EEG and other tests of 14 children aged 16 months to 12 years selected by seizure-free outcome after temporal lobectomy. Four children had mesiotemporal sclerosis, 1 had cortical dysplasia, and 9 had low-grade temporal neoplasms. The children had complex partial seizures (CPS) with symptomatology similar to that of adults with TLE, including decreased responsiveness and automatisms. Automatisms tended to be simpler in the younger children, typically limited to lip smacking and fumbling hand gestures. Scalp/sphenoidal EEG showed anterior/inferior temporal interictal sharp waves and unilateral temporal seizure onset in the 4 children with mesiotemporal sclerosis and in the child with cortical dysplasia, but EEG findings in 9 children with low-grade temporal tumors were complex, including multifocal interictal sharp waves or poorly localized or falsely lateralized EEG seizure onset. In children without tumors, video-EEG was critical to localization of the epileptogenic zone for resection, but in patients with tumors video-EEG was less localizing and its main value was to confirm that the reported behaviors were epileptic seizures with semiology typical of temporal lobe onset.

Activation of distinct multidrug-resistance (P-glycoprotein) genes during rat liver regeneration and hepatocarcinogenesis

The multidrug transporter P-glycoproteins are encoded by three multidrug-resistance (mdr) genes in rodents, designated mdr1a (mdr3), mdr1b (mdr1), and mdr2. Only the first two genes are functionally related to multidrug resistance. Activation of rodent mdr genes during liver regeneration and hepatocarcinogenesis has been reported. In mice, mdr1a is activated in hepatocellular carcinomas (HCCs) produced by various carcinogenic protocols, whereas both mdr1a and mdr2 are activated during liver regeneration. In this communication, we report isolating three gene-specific probes for the rat mdr homologues, which were used as probes in an RNase protection assay to demonstrate that mdr1b mRNA was expressed in HCCs induced by two different protocols. Furthermore, high levels of hepatic mdr1b mRNA but only moderate levels of mdr1a and mdr2 mRNA were seen in preneoplastic lesions in rats treated with 2-acetylaminofluorene. Likewise, highly elevated levels of hepatic mdr1b mRNA but only moderately increased levels of mdr1a and mdr2 mRNA were seen after partial hepatectomy. Nevertheless, the general patterns of tissue-specific expression of these three mdr genes were similar in rats and mice. These results reveal a complex hepatic gene expression pattern during hepatocarcinogenesis and hepatic proliferation for this conserved gene family in rodents.

MR imaging of metastatic GI adenocarcinoma in brain

PURPOSE

To investigate an observed preferential T2-shortening effect seen in patients with intracerebral metastases from adenocarcinoma of the GI tract.

METHODS

Ten patients with intracerebral metastases from adenocarcinoma of the GI tract were evaluated with MR imaging with CT and histopathologic correlation.

RESULTS

Nine of 10 patients demonstrated intracranial masses with decreased signal intensity on T2-weighted images. T1-weighted images showed decreased or isointense signal in all cases. Special histologic staining was performed in four of 10 cases, all of which were positive for increased protein (mucin) with no evidence of blood products or calcium.

CONCLUSION

We propose that the observed preferential T2-shortening effect is secondary to slowing of rotational and translational proton motion caused by increased protein concentration in the form of mucin.

Magnetic resonance of intracranial epidermoids

The magnetic resonance images of seven patients with biopsy-proven epidermoids were evaluated. The epidermoids were hypointense on T1-weighted images. Intermediate density images revealed the tumors to be heterogeneous in signal intensity consisting of areas of hypo- and isointensity. Signal intensity on T2-weighted images was hyperintense and inhomogeneous in all but one case. CT performed in five patients demonstrated the tumors to be well-defined hypodense lesions without contrast enhancement.

Serum enzyme alterations in chronic muscle disease. A biopsy-based diagnostic assessment

The results of interpretation of muscle biopsies were compared retrospectively to activities of serum enzymes and isoenzymes. A total of 137 patients seen at the Cleveland Clinic Foundation in 1986 and 1987 were included in this study. Serum enzymes evaluated were CK, AST, LD, and aldolase (ALS), as well as the percentage CK-MB isoenzyme. The units of CK-MB and the ratios of CK to AST, LD, and ALS were calculated. Descriptive statistics, Kruskal-Wallis one-way analysis of variance, and stepwise logistic regression were performed. A diagnostic algorithm was constructed using a computer-assisted rule generation program. Myopathic diseases yielded a greater mean increase in serum enzyme activity than atrophic diseases. By multivariate stepwise logistic regression, increases in serum AST and CK activity were independently associated with the presence of inflammation in a muscle biopsy specimen. The diagnostic algorithm allowed for the separation of myopathies from atrophies and could identify cases of Duchenne's muscular dystrophy and polymyositis.

Response of CSF IgG to steroids in an 18-month-old with chronic inflammatory polyradiculoneuropathy

During recovery from a upper respiratory infection, an acquired chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) developed in a previously healthy 18-month-old girl. The CIDP followed a monophasic course and left her severely quadriparetic. One year after her neurologic deficit had stabilized, the cerebrospinal fluid (CSF) IgG synthesis rate was markedly elevated, and oligoclonal bands were identified in her CSF, suggesting ongoing inflammation. Her electromyogram (EMG) and nerve biopsy were consistent with a severe acquired segmental demyelinating polyradiculoneuropathy. A course of corticosteroid therapy resulted in dramatic, sustained, clinical and electromyographic improvement, normalization of CSF IgG synthesis rate, and disappearance of the oligoclonal bands. We are not aware of any previous reports that correlate serial measurements of CSF IgG synthesis rate and oligoclonal bands with clinical and electromyographic responses to corticosteroids in a child with acquired CIDP. We suggest that these CSF parameters are potentially useful in demonstrating active inflammation in cases of acquired CIDP even after clinical stabilization of neurologic deficits, predicting response to therapy, and monitoring resolution of the pathologic process.

Systemic vasculitis in association with human immunodeficiency virus infection

Fourteen cases of vasculitis associated with human immunodeficiency virus infection have thus far been described. Five of these cases may be classified as angiocentric immunoproliferative disorders, including benign lymphocytic angiitis, lymphomatoid granulomatosis, and angiocentric lymphoma. We report a case of benign lymphocytic angiitis of T cell lineage. Extensive studies found no evidence of viral antigens in the inflammatory infiltrates, and immunologic evaluation of the pathologic lesions revealed the infiltrating cells to be predominantly CD3+, CD8+, CD4-. A significant number of these lymphocytes demonstrated a deletion of T cell antigen receptor determinants. We believe that in certain cases of human immunodeficiency virus disease, there occurs a spectrum of lymphoproliferative disorders with angiocentric features that lead to the clinical picture of systemic necrotizing vasculitis. Clinicians should be aware of this association.

Proton magnetic resonance imaging in ischemic cerebrovascular disease

Proton magnetic resonance imaging (MRI) using a 0.6- or 1.5-Tesla superconductive magnet was compared with high-resolution computed tomography (CT) in 60 patients with transient ischemic attacks (TIAs) or brain infarction. MRI showed focal parenchymal changes in 84% of patients with TIAs, whereas CT showed similar changes in 42%. The sensitivity of MRI was also greater in patients with infarcts, but the difference between CT and MRI was not as great. Infarcts were usually better delineated by MRI regardless of location. However, MRI failed to reveal cortical infarcts that were clearly seen on contrast-enhanced CT scans and was unable to clearly distinguish subacute from chronic hemorrhagic infarcts. MRI changes were best detected with T2-weighted images and usually appeared as multiple areas of increased signal intensity in the subcortical and periventricular white matter. MRI changes often could not be correlated with the clinical history and neurological findings; identical changes have been seen in patients with no history of cerebrovascular disease.

Magnetic resonance imaging (1.5 tesla) in patients with intractable focal seizures

Magnetic resonance (MR) (1.5 tesla) studies were performed in ten patients with temporal lobe epilepsy and two with temporofrontal epilepsy. Two patients with temporal lobe epilepsy and one with temporofrontal epilepsy exhibited areas of increased signal intensity on T2-weighted images in the mesiobasal portion of the temporal lobe shown by electroencephalography to be the epileptogenic focus; no analogous abnormalities had been found in these patients on computed tomographic scans. Pathologic studies have not revealed a specific ultrastructural correlate for the MR findings in this group of patients. We found MR to be a useful, noninvasive diagnostic adjunct in the presurgical assessment of some patients with temporal lobe epilepsy. Where abnormalities were found, they corresponded with the epileptogenic focus as defined by electroencephalography.

Flecainide: electrophysiologic and antiarrhythmic properties in refractory ventricular tachycardia

Twenty-two patients with coronary artery disease and spontaneous ventricular tachycardia (VT) or ventricular fibrillation (VF) underwent intracardiac electrophysiologic evaluation and, when possible, ambulatory monitoring before and after therapy with flecainide (mean dose 418 +/- 87 mg [mean +/- standard deviation]). An average of 4 antiarrhythmic agents were used and were unsuccessful before therapy with flecainide was begun. During 64 +/- 16 hours of control Holter monitoring in 16 patients, all had 1 or more salvos of VT, as well as ventricular premature complexes (VPCs). Programmed stimulation during the control period induced VT in 17 of 22 patients. After flecainide therapy, Holter monitoring showed elimination of all forms of VT in all but 1 patient, as well as significant reduction of paired VPCs by 95% (p less than 0.03) and single VPCs by 70% (p less than 0.005). Electrophysiologic study during flecainide therapy showed significant increases in AH, HV, PR, QRS and QTc intervals, and the ventricular effective refractory period. Programmed stimulation in 17 patients taking flecainide, with a mean plasma level of 1,075 +/- 521 ng/ml, showed ablation of inducible VT in only 2 patients, a worsening in 5 and continued VT inducibility in 10. Adverse effects that required drug withdrawal were infrequent and encountered in patients who received higher drug levels: 1 patient with congestive heart failure and 1 with severe sinus bradycardia. Thus, although flecainide suppresses complex ventricular arrhythmias on Holter recordings, it rarely alters the response to programmed stimulation. Caution is recommended in its use for recurrent sustained VT or VF and in the interpretation of electrophysiologic studies until the predictive value of programmed stimulation with flecainide therapy is established.

Anterior spinal artery syndrome with chronic traumatic aortic aneurysm

Shortly after severe blunt chest trauma, a young man experienced neurological symptoms suggestive of a spinal cord lesion at the lower thoracic level. The symptoms resolved at first, but then recurred 3 years later and progressed slowly. Neurological workup failed to define the cause until a thoracic aortogram showed an aneurysm in the middle portion of the descending aorta in close proximity to a vessel supplying the anterior spinal artery. After the operative repair with precautions taken to avoid further neurological injury, the neurologic deficit resolved partially. Because of the potential for symptomatic spinal cord ischemia resulting from lesions of the aorta, angiographic delineation of the spinal cord blood supply is valuable in planning operative repair.

Intracranial hemorrhage with amphetamine abuse

Intracranial hemorrhage (ICH) occurred in a drug abuser soon after self-administration of amphetamine. Other reported cases indicate a consistent clinical picture, sometimes fatal or causing permanent neurologic disability.