Multiorgan MRI findings after hospitalisation with COVID-19 in the UK (C-MORE): a prospective, multicentre, observational cohort study

INTRODUCTION

The multiorgan impact of moderate to severe coronavirus infections in the post-acute phase is still poorly understood. We aimed to evaluate the excess burden of multiorgan abnormalities after hospitalisation with COVID-19, evaluate their determinants, and explore associations with patient-related outcome measures.

METHODS

In a prospective, UK-wide, multicentre MRI follow-up study (C-MORE), adults (aged ≥18 years) discharged from hospital following COVID-19 who were included in Tier 2 of the Post-hospitalisation COVID-19 study (PHOSP-COVID) and contemporary controls with no evidence of previous COVID-19 (SARS-CoV-2 nucleocapsid antibody negative) underwent multiorgan MRI (lungs, heart, brain, liver, and kidneys) with quantitative and qualitative assessment of images and clinical adjudication when relevant. Individuals with end-stage renal failure or contraindications to MRI were excluded. Participants also underwent detailed recording of symptoms, and physiological and biochemical tests. The primary outcome was the excess burden of multiorgan abnormalities (two or more organs) relative to controls, with further adjustments for potential confounders. The C-MORE study is ongoing and is registered with ClinicalTrials.gov, NCT04510025.

FINDINGS

Of 2710 participants in Tier 2 of PHOSP-COVID, 531 were recruited across 13 UK-wide C-MORE sites. After exclusions, 259 C-MORE patients (mean age 57 years [SD 12]; 158 [61%] male and 101 [39%] female) who were discharged from hospital with PCR-confirmed or clinically diagnosed COVID-19 between March 1, 2020, and Nov 1, 2021, and 52 non-COVID-19 controls from the community (mean age 49 years [SD 14]; 30 [58%] male and 22 [42%] female) were included in the analysis. Patients were assessed at a median of 5·0 months (IQR 4·2-6·3) after hospital discharge. Compared with non-COVID-19 controls, patients were older, living with more obesity, and had more comorbidities. Multiorgan abnormalities on MRI were more frequent in patients than in controls (157 [61%] of 259 vs 14 [27%] of 52; p<0·0001) and independently associated with COVID-19 status (odds ratio [OR] 2·9 [95% CI 1·5-5·8]; padjusted=0·0023) after adjusting for relevant confounders. Compared with controls, patients were more likely to have MRI evidence of lung abnormalities (p=0·0001; parenchymal abnormalities), brain abnormalities (p<0·0001; more white matter hyperintensities and regional brain volume reduction), and kidney abnormalities (p=0·014; lower medullary T1 and loss of corticomedullary differentiation), whereas cardiac and liver MRI abnormalities were similar between patients and controls. Patients with multiorgan abnormalities were older (difference in mean age 7 years [95% CI 4-10]; mean age of 59·8 years [SD 11·7] with multiorgan abnormalities vs mean age of 52·8 years [11·9] without multiorgan abnormalities; p<0·0001), more likely to have three or more comorbidities (OR 2·47 [1·32-4·82]; padjusted=0·0059), and more likely to have a more severe acute infection (acute CRP >5mg/L, OR 3·55 [1·23-11·88]; padjusted=0·025) than those without multiorgan abnormalities. Presence of lung MRI abnormalities was associated with a two-fold higher risk of chest tightness, and multiorgan MRI abnormalities were associated with severe and very severe persistent physical and mental health impairment (PHOSP-COVID symptom clusters) after hospitalisation.

INTERPRETATION

After hospitalisation for COVID-19, people are at risk of multiorgan abnormalities in the medium term. Our findings emphasise the need for proactive multidisciplinary care pathways, with the potential for imaging to guide surveillance frequency and therapeutic stratification.

FUNDING

UK Research and Innovation and National Institute for Health Research.

Clinical characteristics with inflammation profiling of long COVID and association with 1-year recovery following hospitalisation in the UK: a prospective observational study

BACKGROUND

No effective pharmacological or non-pharmacological interventions exist for patients with long COVID. We aimed to describe recovery 1 year after hospital discharge for COVID-19, identify factors associated with patient-perceived recovery, and identify potential therapeutic targets by describing the underlying inflammatory profiles of the previously described recovery clusters at 5 months after hospital discharge.

METHODS

The Post-hospitalisation COVID-19 study (PHOSP-COVID) is a prospective, longitudinal cohort study recruiting adults (aged ≥18 years) discharged from hospital with COVID-19 across the UK. Recovery was assessed using patient-reported outcome measures, physical performance, and organ function at 5 months and 1 year after hospital discharge, and stratified by both patient-perceived recovery and recovery cluster. Hierarchical logistic regression modelling was performed for patient-perceived recovery at 1 year. Cluster analysis was done using the clustering large applications k-medoids approach using clinical outcomes at 5 months. Inflammatory protein profiling was analysed from plasma at the 5-month visit. This study is registered on the ISRCTN Registry, ISRCTN10980107, and recruitment is ongoing.

FINDINGS

2320 participants discharged from hospital between March 7, 2020, and April 18, 2021, were assessed at 5 months after discharge and 807 (32·7%) participants completed both the 5-month and 1-year visits. 279 (35·6%) of these 807 patients were women and 505 (64·4%) were men, with a mean age of 58·7 (SD 12·5) years, and 224 (27·8%) had received invasive mechanical ventilation (WHO class 7-9). The proportion of patients reporting full recovery was unchanged between 5 months (501 [25·5%] of 1965) and 1 year (232 [28·9%] of 804). Factors associated with being less likely to report full recovery at 1 year were female sex (odds ratio 0·68 [95% CI 0·46-0·99]), obesity (0·50 [0·34-0·74]) and invasive mechanical ventilation (0·42 [0·23-0·76]). Cluster analysis (n=1636) corroborated the previously reported four clusters: very severe, severe, moderate with cognitive impairment, and mild, relating to the severity of physical health, mental health, and cognitive impairment at 5 months. We found increased inflammatory mediators of tissue damage and repair in both the very severe and the moderate with cognitive impairment clusters compared with the mild cluster, including IL-6 concentration, which was increased in both comparisons (n=626 participants). We found a substantial deficit in median EQ-5D-5L utility index from before COVID-19 (retrospective assessment; 0·88 [IQR 0·74-1·00]), at 5 months (0·74 [0·64-0·88]) to 1 year (0·75 [0·62-0·88]), with minimal improvements across all outcome measures at 1 year after discharge in the whole cohort and within each of the four clusters.

INTERPRETATION

The sequelae of a hospital admission with COVID-19 were substantial 1 year after discharge across a range of health domains, with the minority in our cohort feeling fully recovered. Patient-perceived health-related quality of life was reduced at 1 year compared with before hospital admission. Systematic inflammation and obesity are potential treatable traits that warrant further investigation in clinical trials.

FUNDING

UK Research and Innovation and National Institute for Health Research.

Transition of Renal Patients Using AlloSure Into Community Kidney Care (TRACK): Protocol for Long-Term Allograft Surveillance in Renal Transplant Recipients

BACKGROUND

Patients with end-stage kidney disease require complex and expensive medical management. Kidney transplantation remains the treatment of choice for end-stage kidney disease and is considered superior to all other modalities of renal replacement therapy or dialysis. However, access to kidney transplant is limited by critical supply and demand, making it extremely important to ensure longevity of transplanted kidneys. This is prevented through lifelong immunosuppression, with caution not to overly suppress the immune system, resulting in toxicity and harm. Transition of care to community nephrologists after initial kidney transplantation and monitoring at a transplant center is an important process to ensure delivery of effective and patient-centric care closer to home. Once transplanted, laborious surveillance of the immune system and monitoring for potential rejection and injury are undertaken through an armamentarium of screening modalities. Posttransplant surveillance for kidney function and injury remains key to follow-up care. While kidney function, quantified by estimated glomerular filtration rate and serum creatinine, and kidney injury, measured by proteinuria and hematuria, are standard biomarkers used to monitor injury and rejection posttransplant, they have recently been demonstrated to be inferior in performance to that of AlloSure (CareDx Inc, Brisbane, CA) circulating donor-derived, cell-free DNA (dd-cfDNA).

OBJECTIVE

The outcomes and methods of monitoring renal transplant recipients posttransplant have remained stagnant over the past 15 years. The aim of this study is to consider intensive surveillance using AlloSure dd-cfDNA in an actively managed protocol, assessing whether it increases long-term allograft survival in kidney transplant recipients compared with current standard clinical care in community nephrology.

METHODS

The study protocol will acquire data from a phase IV observational trial to assess a cohort of renal transplant patients managed using AlloSure dd-cfDNA and patient care managers versus 1000 propensity-matched historic controls using United Network for Organ Sharing U.S. Scientific Registry of Transplant Recipients data. Data will be managed in a centralized electronic data server. The primary outcome will be superior allograft survival, as a composite of return to dialysis, retransplant, death due to allograft failure, and death with a functional graft (infection, malignancy, and cardiovascular death). The secondary endpoints will assess improved kidney function through decline in estimated glomerular filtration rate and immune activity through development of donor-specific antibodies.

RESULTS

The total sample is anticipated to be 3500 (2500 patients managed with AlloSure dd-cfDNA and 1000 propensity-matched controls). Active enrollment began in November 2020.

CONCLUSIONS

Based on a significant literature base, we believe implementing the surveillance of dd-cfDNA in the kidney transplant population will have a positive impact on graft survival. Through early identification of rejection and facilitating timely intervention, prolongation of allograft survival versus those not managed by dd-cfDNA surveillance protocol should be superior.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

PRR1-10.2196/25941.

Nicotinic regulation of local and long-range input balance drives top-down attentional circuit maturation

Cognitive function depends on frontal cortex development; however, the mechanisms driving this process are poorly understood. Here, we identify that dynamic regulation of the nicotinic cholinergic system is a key driver of attentional circuit maturation associated with top-down frontal neurons projecting to visual cortex. The top-down neurons receive robust cholinergic inputs, but their nicotinic tone decreases following adolescence by increasing expression of a nicotinic brake, Lynx1 Lynx1 shifts a balance between local and long-range inputs onto top-down frontal neurons following adolescence and promotes the establishment of attentional behavior in adulthood. This key maturational process is disrupted in a mouse model of fragile X syndrome but was rescued by a suppression of nicotinic tone through the introduction of Lynx1 in top-down projections. Nicotinic signaling may serve as a target to rebalance local/long-range balance and treat cognitive deficits in neurodevelopmental disorders.

Secondary non-invasive prenatal screening for fetal trisomy: an effectiveness study in a public health setting

OBJECTIVE

To evaluate the effectiveness of secondary screening using non-invasive prenatal testing (NIPT) in a routine NHS setting including test performance, turn-around times (TATs) and no-call (failure to obtain result) rates. To examine the influence of maternal and fetal characteristics on test performance.

DESIGN

Retrospective cohort.

SETTING

London teaching hospital.

SAMPLE

A total of 8651 pregnancies undergoing screening for fetal trisomy using NIPT provided by an NHS cell-free DNA screening laboratory - the SAFE laboratory.

METHODS

Screening test evaluation and TATs. Univariate and multivariate logistic regression analysis to identify significant predictors of no-call results and reported by low fetal fraction (<2%), very high fetal fraction (>40%) and processing failure.

MAIN OUTCOME MEASURES

Test performance, TATs and no-call rates, factors affecting no-call results.

RESULTS

Average TAT was 4.0 days (95% CI 4.0-4.2 days). Test sensitivities for trisomies 21 and 13/18 were 98.9% (95% CI 95.9-99.9%) and 90.4% (95% CI 80.0-96.8%), respectively. The overall no-call rate was 32/8651 (0.37%, 95% CI 0.26-0.52%). The overall risk of a no-call result was influenced by gestational age, dichorionic twin pregnancy, history of malignancy and pregnancies affected by trisomy 13/18, but not by maternal weight or use of low-molecular-weight heparin.

CONCLUSIONS

High-throughput NIPT can be effectively embedded into a public health NHS setting. TATs of 4 days and no-calls of <0.5% were well within clinically desirable tolerances. Gestational age, maternal weight, assisted reproductive techniques, use of low-molecular-weight heparin and past history of malignancy did not have major impacts on test no-call rates and should not constitute reasons for withholding the option of NIPT from women.

TWEETABLE ABSTRACT

Turn-around times of 4 days, no-call (test failure) rates of 0.37% and highly accurate NIPT can be successfully embedded in the NHS.

Practical methods for the measurement of logP for surfactants

Hydrophobicity is a commonly used parameter in quantitative structure activity relationships. The ability to determine the octanol-water partition coefficient (logP) empirically for non-ionizing, non-surfactant type chemicals using traditional stir-flask methods has been successful and well documented. In comparison the ability to measure logP for surfactants is considered impractical due to their amphiphilic nature, which gives them a tendency to form micelles and reside at the octanol-water interface. In this study we have shown that working with compounds below their critical micelle concentrations (CMC), at the experimental concentrations, it is possible to obtain experimental logP values for a series of sulphobetaines using the stir-flask method coupled with reversed phase-high performance liquid chromatography (RP-HPLC). Until now the ability to verify calculated logP values for surfactants has been limited. Measuring logP as described here can now be applied to other surfactants to validate existing and new modifications to the fragment method.

A case study of delayed HIV-1 seroconversion highlights the need for Combo assays

Summary

This report describes a case in which a patient took at least four months to seroconvert to anti-HIV positivity. A concomitant CMV infection probably contributed to the profound immune suppression observed. It is essential that fourth generation HIV antigen/antibody combo assays be used to ensure that such cases are not missed.

Inflammatory myofibroblastic tumor of the orbit with associated enhancement of the meninges and multiple cranial nerves

Inflammatory myofibroblastic tumor (IMT), Tolosa-Hunt syndrome (THS), and idiopathic hypertrophic pachymeningitis (IHP) seem to be part of a spectrum of disorders that have diverse locations but similar histologic and imaging findings. We report a case of a 50-year-old man presenting with multiple progressive cranial nerves palsies with leptomeningeal cranial nerve enhancement on MRI (II, V1-V3, and X), orbital and infraorbital masses, prominence within the left cavernous sinus, and diffuse dural enhancement. Biopsies of the orbital lesion and infraorbital nerve revealed IMT. The patient's lesions, symptoms, and dural enhancement quickly improved with steroid administration and nearly resolved over multiple subsequent scans over the next few months. This case illustrates a rare case of pseudotumor mimicking a more aggressive appearance that would usually portend a case of malignancy. There is a potential association of IMT, THS, and IHP, which may have existed in a concomitant fashion in this patient. The case also describes the unique finding of enhancement of the cisternal segments of multiple cranial nerves (simulating leptomeningeal malignant involvement), which may be related to inflammatory perineural edema or ischemic neuropathy.

Metachronous, multicentric giant cell tumor of the sphenoid bone with histologic, CT, MR imaging, and positron-emission tomography/CT correlation

Giant cell tumor (GCT) of the sphenoid bone is a relatively rare entity and metachronous multicentric GCT of the sphenoid is even rarer; we are aware of only 3 previous cases in the literature. We describe here a tumor of the sphenoid bone that was identified 15 years after multiple resections of a GCT of the left inferior pubic ramus. Correlation is made between the histopathologic findings, MR imaging of the brain, CT of the head, and fusion positron-emission tomography (PET)/CT scan performed with fluorine-18 fluoro-2-deoxy-D-glucose (18F-FDG). This report is the first to describe the appearance of a GCT of the sphenoid bone on a fusion PET/CT examination. High metabolic activity in the base of the skull adjacent to the middle cranial fossa was demonstrated in a fashion similar to that of the known pelvic lesion. This case also demonstrates that the increased metabolic activity seen in a GCT of the sphenoid bone may be partially obscured by the adjacent physiologic high metabolic activity of the brain.

Reversible findings of restricted diffusion in 5-flourouracil neurotoxicity

A 35-year-old woman presented with neurotoxicity correlated to an i.v. regimen of 5-fluorouracil as episodes of acute confusional state and abnormalities of symmetrically restricted diffusion in the periventricular white matter and corpus callosum. On discontinuing the medication, the areas of severely restricted diffusion had entirely resolved, with minimal residual T2 signal abnormality. In this case, immediate discontinuation of the chemotherapeutic agent apparently reversed the patient's symptoms and findings on MRI. The scant information available in the published literature regarding this phenomenon is reviewed with regard to 5-fluorouracil.

The fragile X tremor ataxia syndrome in the differential diagnosis of multiple system atrophy: data from the EMSA Study Group

The recent identification of fragile X-associated tremor ataxia syndrome (FXTAS) associated with premutations in the FMR1 gene and the possibility of clinical overlap with multiple system atrophy (MSA) has raised important questions, such as whether genetic testing for FXTAS should be performed routinely in MSA and whether positive cases might affect the specificity of current MSA diagnostic criteria. We genotyped 507 patients with clinically diagnosed or pathologically proven MSA for FMR1 repeat length. Among the 426 clinically diagnosed cases, we identified four patients carrying FMR1 premutations (0.94%). Within the subgroup of patients with probable MSA-C, three of 76 patients (3.95%) carried premutations. We identified no premutation carriers among 81 patients with pathologically proven MSA and only one carrier among 622 controls (0.16%). Our results suggest that, with proper application of current diagnostic criteria, FXTAS is very unlikely to be confused with MSA. However, slowly progressive disease or predominant tremor are useful red flags and should prompt the consideration of FXTAS. On the basis of our data, the EMSA Study Group does not recommend routine FMR1 genotyping in typical MSA patients.

Intracranial metastasis via transplacental (vertical) transmission of maternal small cell lung cancer to fetus: CT and MRI findings

We present the computed tomography (CT) and magnetic resonance imaging (MRI) findings of brain metastases in an unusual case of a premature, 33-week gestational age neonate who was emergently delivered from a mother suspected of having lung cancer according to imaging performed during the third trimester of pregnancy. Owing to the presence of placental metastases noted after delivery, the fetus had initial screening with brain MRI and chest/abdomen CT as well as serial screening imaging studies during the first 5 months of life, all of which were apparently normal. However, serial examinations eventually revealed a cerebellar lesion that significantly improved after chemotherapy but recurred and enlarged within a few months. This lesion was later confirmed to be metastasis by subsequent biopsy and resection. More metastatic lesions were identified in the frontal and temporal lobes on follow-up MRI. In the setting of aggressive maternal malignancy (without known fetal primary malignancy) an intracranial mass can, on the exceedingly rare occasion, result from maternal high-grade malignancy and the neuroradiologist should be alerted to this phenomenon.

Apolipoprotein E is upregulated in olfactory bulb glia following peripheral receptor lesion in mice

Apolipoprotein E (apoE), a lipid transporting protein, has been postulated to participate in nerve regeneration. To better clarify apoE function in the olfactory system, we evaluated the amount and distribution of apoE in the olfactory bulb following olfactory nerve lesion in mice. Olfactory nerve was lesioned in 2- to 4-month-old mice by intranasal irrigation with Triton X-100. Olfactory bulbs were collected at 0, 3, 7, 21, 42, and 56 days postlesion, and both apoE concentrations and apoE distribution were determined. ApoE levels, as determined by immunoblot analysis, were twofold greater than normal during nerve degeneration at 3 days. ApoE levels remained elevated by approximately 1.5 times normal levels at 7 through 21 days after injury and returned to baseline by 56 days. Immunocytochemical studies supported these observations. ApoE immunoreactivity was prominent on the olfactory nerve at 3 days after lesion and decreased to baseline levels at later time periods. Double-labeling immunocytochemical studies confirmed that both reactive astroglia and microglia produced detectable amounts of apoE following the lesion. Return of apoE expression to baseline paralleled measures of olfactory nerve maturation as measured by olfactory marker protein. These data suggest that apoE increases concurrent with nerve degeneration. ApoE may facilitate efficient regeneration perhaps by recycling lipids from degenerating fibers for use by growing axons. The association of apoE genotype with dementing illnesses may represent a diminished ability to support a lifetime of nerve regeneration.

Imaging of acute subarachnoid hemorrhage with a fluid-attenuated inversion recovery sequence in an animal model: comparison with non-contrast-enhanced CT

BACKGROUND AND PURPOSE

Fluid-attenuated inversion recovery (FLAIR) MR imaging sequences have been previously described in the evaluation of acute subarachnoid hemorrhage (SAH) in human subjects and have demonstrated good sensitivity. The purpose of this study was to evaluate a FLAIR sequence in an animal model of SAH and to compare the results with those obtained with non-contrast-enhanced CT.

METHODS

SAH was experimentally induced in 18 New Zealand rabbits by injecting autologous arterial blood into the subarachnoid space of the foramen magnum. Nine animals had high-volume (1-2 mL) injections, and nine animals had low-volume (0.2-0.5 mL) injections. Four control animals were injected with 0.5 mL of saline. The animals were imaged with a FLAIR sequence and standard CT 2-5 hours after injection. Gross pathologic evaluation of seven of the animals was performed. Four blinded readers independently evaluated the CT and FLAIR images for SAH and graded the probability of SAH on a scale of 1 to 5 (1 = no hemorrhage, 5 = definite hemorrhage).

RESULTS

Overall, the sensitivity of FLAIR was 89%, and the sensitivity of CT was 39% (P <.01). In animals with a high volume of SAH, the sensitivity of FLAIR was 100%, and the sensitivity of CT was 56%. In animals with a low volume of SAH, the sensitivity of FLAIR was 78%, and the sensitivity of CT was 22%. The specificity of FLAIR in animals without SAH was 100%, and the specificity of CT was 100%. The average reader score for FLAIR was 3.8, and that for CT was 2.2 (P <.001). Reader scores for FLAIR were higher than those for CT in 94% (P <.01) of animals with SAH and in 25% of animals without SAH (P >.05). Seven animals underwent gross pathologic examination, and all had blood in the subarachnoid space around the brain stem.

CONCLUSION

FLAIR was more sensitive than CT in the evaluation of acute SAH in this model, especially when a high volume of SAH was present. This study provides a model for further experimentation with MR imaging in the evaluation of SAH. These findings are consistent with those of current clinical literature, which show FLAIR to be an accurate MR sequence in the diagnosis of SAH.

The simultaneous determination of diazepam and its three metabolites in dog plasma by high-performance liquid chromatography with mass spectroscopy detection

A fast, sensitive and specific LC/MS/MS method for the simultaneous determination of diazepam and its three metabolites, oxazepam, temazepam and desmethyldiazepam, in dog plasma is described. The method consists of an automated 96-well solid phase extraction procedure and electrospray LC/MS/MS analysis. D(5)-Diazepam is used as the internal standard for all the compounds. Intra-day and inter-day assay coefficients of variations are less than 12.7%. The lower limit of quantitation (LLOQ) is 1 nM for each analyte, based on 0.1 ml aliquots of dog plasma. The analytical run time was 5 min. Linearity is observed over the range of 1--500 nM. This method has been used to support the discovery of pharmacokinetic studies.

Comparison of three joint simulator wear debris isolation techniques: acid digestion, base digestion, and enzyme cleavage

Quantification of ultrahigh molecular weight polyethylene (UHMWPE) wear debris remains a challenging task in orthopedic device analysis. Currently, the weight loss method is the only accepted practice for quantifying the amount of wear generated from a PE component. This technique utilizes loaded soak controls and weight differences to account for polymeric material lost through wear mechanisms. This method enables the determination of the amount of wear in the orthopedic device, but it provides no information about debris particulate size distribution. In order to shed light on wear mechanisms, information about the wear debris and its size distribution is necessary. To date, particulate isolation has been performed using the base digestion technique. The method uses a strong base, ultracentrifugation, and filtration to digest serum constituents and to isolate PE debris from sera. It should be noted that particulate isolation methods provide valuable information about particulate size distribution and may elucidate the mechanisms of wear associated with polymeric orthopedic implants; however, these techniques do not yet provide a direct measure of the amount of wear. The aim of this study is to present alternative approaches to wear particle isolation for analysis of polymer wear in total joint replacements without recourse to ultracentrifugation. Three polymer wear debris isolation techniques (the base method, an acid treatment, and an enzymatic digestion technique) are compared for effectiveness in simulator studies. A requirement of each technique is that the wear particulate must be completely devoid of serum proteins in order to effectively image and count these particles. In all methods the isolation is performed through filtration and chemical treatment. Subsequently, the isolated polymer particles are imaged using scanning electron microscopy and quantified with digital image analysis. The results from this study clearly show that isolation can be performed without the use of ultracentrifugation and that these methods provide a viable option for wear debris analysis.

Consultant appraisals. With due respect

Consensus is needed on which management competencies should be included in doctors' appraisals. One trust employed management consultants to find out the views of senior doctors, managers, directors and patients. Common themes included concern for standards, effective use of information, openness, integrity and insight. The results will be used to guide future recruitment.

Apolipoprotein E immunoreactivity in human and mouse olfactory bulb

We evaluated the distribution of apolipoprotein E (apoE) immunoreactivity in mouse and human olfactory bulbs. ApoE immunoreactivity was present in the olfactory nerve and around the glomeruli. Immunoreactivity was seen in somata that appeared to be glial. No neuronal staining was seen. The apoE immunoreactivity was also present in the mouse olfactory bulb subependymal layer. The specificity of immunoreactivity was confirmed with apoE-deficient mice (apoE gene knock-out mice, apoE KO) which did not display any immunoreactivity. The presence of apoE around glomeruli and nerve suggest that apoE is associated with the continuous degeneration and regeneration processes that occur in the olfactory nerve. Experimental manipulation of the olfactory nerve may be a useful technique to determine the functions of apoE in a well-defined neural system.

Comparison of the effects of aging on 5-HT7 and 5-HT1A receptors in discrete regions of the circadian timing system in hamsters

The circadian timekeeping system exhibits many functional changes with aging, including a loss of sensitivity to time cues such as systemic injections of the serotonergic agonist, 8-hydroxy-2-(di-n-propylamino)tetralin (8-OH-DPAT). In order to elucidate the neurochemical mechanisms responsible for this age-related loss of sensitivity of the circadian pacemaker to serotonin agonists, the present study used quantitative autoradiography to determine whether aging decreases serotonin receptor populations in male Syrian hamsters. Four neuroanatomical regions that regulate circadian timekeeping were studied (the suprachiasmatic nuclei [SCN], the lateral geniculate nuclei [LGN], and the median raphe nucleus [MRN] and dorsal raphe nucleus [DRN]). The specific binding of [3H]8-OH-DPAT to serotonin7 (5-HT7) and serotonin1A (5-HT1A) receptors was investigated by competitive inhibition with ritanserin and pindolol, respectively. The results showed that the SCN, IGL, MRN, and DRN of the male Syrian hamster exhibited specific binding of [3H]8-OH-DPAT to both the 5-HT7 and 5-HT1A receptors, and that the latter receptor subtype is more abundant in all of these regions. At 17-19 months of age, a 50% decrease in 5-HT7 receptors was found in the DRN but not in any other regions. No significant age-related changes in 5-HT1A receptors were observed in any regions examined. The finding that a marked decrease in 5-HT7 receptors occurs in the DRN at the age previously characterized by loss of sensitivity to 8-OH-DPAT suggests that this region and this receptor subtype play important roles in 8-OH-DPAT induction of circadian phase shifts in vivo and that they constitute an important locus of aging in the circadian timing system.

The Fluctuating Abundance of Endangered Mammals on Bernier And Dorre Islands, Western Australia - Conservation Implications

Bernier and Dorre Islands in Shark Bay, Western Australia, provide refuge to populations of five species of threatened mammals that are extinct on the mainland other than as reintroduced or captive populations. This paper provides estimates of changes in population size of four species over three years from 1988-9 to 1991-2. The period from November 1986 to March 1989 was one of below average rainfall intensifying to severe drought on the islands; the period from mid 1989 to 1992 was one of average to above-average rainfall. Three of the four species (L. hirsutus, B. lesueur and P. bougainville) showed substantial and significant increases and one species (L. fasciatus) showed a small but non-significant increase in abundance. Combined estimates of minimum population size for both islands in 1991-2 vary from c. 4,000 P. bougainville to c. 10,000 L. fasciatus. If these densities are regarded as typical of average rainfall years then the drought in the late 1980s reduced populations of P. bougainville by up to 75%, B. lesueur by 65%, and L. hirsutus by up to 60%. Combined estimates for the four species give densities for the community of medium-sized mammals which vary between 160 km-2 in drought and 260 km-2 in years of average to above average rainfall.

Quantitation of the changes in splenic architecture during the rejection of cardiac allografts or xenografts

BACKGROUND

The spleen plays a central role in the generation of both cellular and antibody responses during graft rejection. Although changes in lymphocyte function have been extensively analyzed in vitro, there have been limited attempts at quantitating the structural changes in the lymphoid compartments within the spleen during graft rejection.

METHODS

We describe here a means of quantitating the histological changes in the spleen using immunohistochemical techniques and computerized image analysis.

RESULTS

Allograft rejection at 6 days after transplant is characterized by a threefold increase in the T cell-rich areas of the periarteriolar lymphoid sheaths (PALs). The follicular areas are enlarged and germinal centers appear in 55% of the white pulp regions. Acute xenograft rejection, 4 days after transplant, is specifically accompanied by a 2.3-fold increase in the marginal zone (MZ) and an increase in the numbers of B cells in the red pulp of the spleen. The expansion of both PALs and follicular/germinal centers during xenograft rejection is comparable to that observed during allograft rejection. We also investigated the effect of two immunosuppressants, leflunomide and cyclosporine, on the spleen of rats with hamster hearts. Leflunomide, which prevents acute xenograft rejection, prevented the increase in PALs and significantly reduced the areas comprising the MZ and follicles. Cyclosporine, which does not alter the tempo of xenograft rejection and only partially inhibited xenospecific antibody production, inhibited the increase in PALs and the appearance of germinal centers, while permitting a modest increase in the area of MZ and follicles.

CONCLUSIONS

These observations collectively suggest that both T cell-dependent and T cell-independent responses are stimulated by the transplanted xenograft. However, the T cell-independent responses that initiate xenograft rejection are characterized by very modest increases in the area of MZ and follicles within the white pulp of the spleen.

Redesigning ambulatory care business processes supporting clinical care delivery

The first step in redesigning the health care delivery process for ambulatory care begins with the patient and the business processes that support the patient. Patient-related business processes include patient access, service documentation, billing, follow-up, collection, and payment. Access is the portal to the clinical delivery and care management process. Service documentation, charge capture, and payment and collection are supporting processes to care delivery. Realigned provider networks now demand realigned patient business services to provide their members/customers/patients with improved service delivery at less cost. Purchaser mandates for cost containment, health maintenance, and enhanced quality of care have created an environment where every aspect of the delivery system, especially ambulatory care, is being judged. Business processes supporting the outpatient are therefore being reexamined for better efficiency and customer satisfaction. Many health care systems have made major investments in their ambulatory care environment, but have pursued traditional supporting business practices--such as multiple access points, lack of integrated patient appointment scheduling and registration, and multiple patient bills. These are areas that are appropriate for redesign efforts--all with the customer's needs and convenience in mind. Similarly, setting unrealistic expectations, underestimating the effort required, and ignoring the human elements of a patient-focused business service redesign effort can sabotage the very sound reasons for executing such an endeavor. Pitfalls can be avoided if a structured methodology, coupled with a change management process, are employed. Deloitte & Touche Consulting Group has been involved in several major efforts, all with ambulatory care settings to assist with the redesign of their business practices to consider the patient as the driver, instead of the institution providing the care.

Vaginal wall sling for anatomical incontinence and intrinsic sphincter dysfunction: efficacy and outcome analysis

PURPOSE

A prospective cohort study was done to determine the efficacy and clinical outcome of a new technique for anterior vaginal wall sling construction to treat urinary incontinence due to intrinsic sphincter dysfunction or anatomical incontinence.

MATERIALS AND METHODS

Preoperative evaluation included lateral cystography, video urodynamics, cystoscopy and incontinence staging. Postoperative subjective and objective staging outcome measures were prospectively assigned at predetermined regular intervals by a third party.

RESULTS

Of the patients 95 had intrinsic sphincter dysfunction and 65 had anatomical incontinence. The repair failed in 7% of the 160 patients who had recurrent incontinence during followup and 9% had de novo urgency incontinence. Time to failure comparing patients with intrinsic sphincter dysfunction and anatomical incontinence was modeled using Kaplan-Meier survival curves, and the log rank test showed no significant difference between the groups (p > 0.05). Logistic regression covariates revealed no significant predictive factors for postoperative failures. Preoperative patient age was the only predictive factor for de novo instability (logistic regression model p < 0.05).

CONCLUSIONS

Our initial results indicate that the 2 groups are indistinguishable to date based on current clinical and experimental statistics except for time to full recovery of postoperative voiding and incidence of postoperative instability (regression model p < 0.05).

Case study: anorexia nervosa and autistic disorder in an adolescent girl

The development of anorexia nervosa in a high-functioning, early adolescent, autistic female is described. This case raises the issue of co-occurrence of childhood-onset disorders sharing the phenomena of obsessions and compulsions. The role of dysregulation of the serotonergic neurotransmitter system as a common underlying mechanism in these disorders is suggested. Psychoactive agents affecting the serotonin system and in particular the atypical neuroleptic risperidone may be of value in these disorders. There is added benefit to the combined use of biological and behavioral therapies.

Spontaneous mutants recovered from liver and germ cell tissue of low copy number lacI transgenic rats

The finding of a large discordance between animal species in their response to a carcinogenic challenge, has led to the realization that the useful extrapolation of animal test data to humans requires a better understanding of animal interspecies differences. With the development of transgenic shuttle vector based animal systems we are now able to study mutation of the same genetic target in both mice and rats. We have begun to analyze mutants recovered from rat lines carrying low copy numbers of the same lambda/lacI constructs carried by the Big Blue mouse. A large database on mutations in lacI transgenic mice is already available for comparison. The data indicate that the differences between the mutations recovered from rat liver and germ cell tissues are similar to those recovered from transgenic mice, but when compared with a large database of mutations available for mice, some site-to-site differences may exist. This study represents the first interspecies look into the molecular nature of mutations in the lacI transgenic rodents.

Pharmacologically induced regression of chronic transplant rejection

Chronic rejection, characterized by a progressive obliterative arteriopathy, is a major cause of graft failure in long-surviving human transplants for which there is no effective treatment. Leflunomide, an isoxazol derivative, has been shown to be a novel immunomodulatory drug that profoundly suppresses the immune response. In this study, 58 Fisher-344 rats received cardiac transplantation from Lewis rats. All the recipients were given CsA at 2.5 mg/kg for 5 days postoperatively. Without further treatments, the arterial intima was progressively injured by mononuclear cell infiltration and Ab deposition. Smooth muscle cell and fibroblast proliferation in the intima became a predominant phenomenon by day 90. CsA was ineffective in controlling the progress of arterial intimal thickening when treatment began on day 30. Leflunomide at 5 mg/kg failed to control arterial intimal thickening by day 60 when therapy began on day 30. However, the progress of arterial intimal thickening was significantly inhibited by day 90 when the dosage of leflunomide had been increased to 10 mg/kg on day 60. Combined therapy with leflunomide and CsA at 5 mg/kg for 30 days dramatically reversed the arterial thickening by day 60. After increasing the dosages of both leflunomide and CsA to 10 mg/kg on day 60, the combination therapy steadily controlled the chronic rejection. Only the combination therapy significantly down-regulated circulating antidonor IgM and IgG titers. In rat smooth muscle cell culture, this same drug combination had a synergistic inhibitory effect on proliferation. Therefore, the combination therapy of leflunomide and CsA could reverse and control the progress of chronic rejection, while leflunomide, at higher dosage as a monotherapy, could stabilize chronic rejection in this model. The mechanism of the regression of chronic rejection by leflunomide and cyclosporine may be related to their in vitro abilities to control not only lymphocyte but smooth muscle cell proliferation, as well. The synergistic effect of these two drugs on vascular smooth muscle cell proliferation in vitro may be an important part of this novel activity. This unique feature holds intriguing possibilities for treating established chronic rejection.

Small bowel obstruction caused by a retained percutaneous endoscopic gastrostomy gastric flange

In 1980 Gauderer et al.1 described a pull-through technique to position a percutaneous endoscopic gastrostomy (PEG) tube. Recognized complications are pulmonary aspiration, peritonitis and haemorrhage. Longer term problems include peristomal wound infection, gastrocolic fistula and frequent tube blockage. The reported overall mortality rate is less than 1 per cent2,3.

Mentally disordered firesetters

Research on firesetters suggests that the majority are mentally disordered. Schizophrenics are slightly over-represented but most arsonists are characterised by abnormal personalities. While motives for firesetting are usually mixed, anger and revenge are the commonest. Arsonists tend to be underassertive individuals with poor interpersonal skills who are unable to deal effectively with conflict, anger and frustration. This perhaps explains their choice of fire as a weapon.

Planning a continuing education program: the model for health education planning

1. Development of CE programs for occupational health nurses is integral to professional development. Occupational health nurses are constantly being required to increase and upgrade skills. 2. Evolving issues in health care reform reflect an emphasis on the cost effective, quality care provided by well prepared occupational health nurses. Thus, the need for providing high quality programs and resources for occupational health nurses becomes a challenge for CE providers. 3. The Model for Health Education Planning (MHEP) is used to describe the development of a program. The MHEP includes six phases: initiation, needs assessment, goal setting, planning/programming, implementation, and evaluation. 4. Use of the MHEP ensures that the program planning process is achieved in an appropriate manner. The focus is on meeting the needs of the learner.