Quantitative assessment of iron accumulation in the deep gray matter of multiple sclerosis by magnetic field correlation imaging

BACKGROUND AND PURPOSE

Deposition of iron has been recognized recently as an important factor of pathophysiologic change including neurodegenerative processes in multiple sclerosis (MS). We propose that there is an excess accumulation of iron in the deep gray matter in patients with MS that can be measured with a newly developed quantitative MR technique--magnetic field correlation (MFC) imaging.

MATERIALS AND METHODS

With a 3T MR system, we studied 17 patients with relapsing-remitting MS and 14 age-matched healthy control subjects. We acquired MFC imaging using an asymmetric single-shot echo-planar imaging sequence. Regions of interest were selected in both deep gray matter and white matter regions, and the mean MFC values were compared between patients and controls. We also correlated the MFC data with lesion load and neuropsychologic tests in the patients.

RESULTS

MFC measured in the deep gray matter in patients with MS was significantly higher than that in the healthy controls (P < or = .03), with an average increase of 24% in the globus pallidus, 39.5% in the putamen, and 30.6% in the thalamus. The increased iron deposition measured with MFC in the deep gray matter in the patients correlated positively with the total number of MS lesions (thalamus: r = 0.61, P = .01; globus pallidus: r = 0.52, P = .02). A moderate but significant correlation between the MFC value in the deep gray matter and the neuropsychologic tests was also found.

CONCLUSION

Quantitative measurements of iron content with MFC demonstrate increased accumulation of iron in the deep gray matter in patients with MS, which may be associated with the disrupted iron outflow pathway by lesions. Such abnormal accumulation of iron may contribute to neuropsychologic impairment and have implications for neurodegenerative processes in MS.

Predictability of the clinical course of juvenile dermatomyositis based on initial muscle biopsy: A retrospective study of 72 patients

OBJECTIVE

Except when the diagnosis of juvenile dermatomyositis (DM) is in doubt, a case has not been made for routine muscle biopsy (MB). We sought to determine whether MB findings prior to systemic therapy have prognostic value.

METHODS

We reviewed the hospital records and slides prepared from the initial open MB of 72 patients treated at one center between 1977 and 2002 and followed for a minimum of 2 years. None of the patients had received a course of systemic corticosteroid therapy at the time of MB. Our approach to MB evaluation was based on recent discussions with muscle pathology experts to develop criteria for assessing inflammation, vasculopathy, myofiber atrophy, regeneration, acute and chronic myopathic change, and stromal changes. Using simple and multivariate logistic regression, we tested each MB parameter for ability to predict outcome using 2 published classification systems.

RESULTS

Extensive active myopathic changes (excluding regeneration) and central nuclei without basophilia predicted chronic juvenile DM. Severe arteropathic change, positive arterial direct immunofluorescence, obvious foci of severe capillary loss/endomysial fibrosis, and muscle infarcts predicted chronic juvenile DM, particularly with ulceration. Other MB parameters, regardless of severity, were not significant predictors of chronic juvenile DM versus limited disease.

CONCLUSION

A scoring system for evaluating pretreatment MB in juvenile DM that focuses on extent of necrotizing myopathy, severity of vasculopathy, and features of established chronicity such as central nucleation of nonbasophilic myofibers may provide a basis for stratification of therapeutic regimens according to risk for chronic disease. The validity of our findings should be prospectively tested.

Hepatocyte glycogen accumulation in patients undergoing dietary management of urea cycle defects mimics storage disease

OBJECTIVES

Anecdotal reports have described excess hepatocyte glycogen in patients with urea cycle enzyme defects. Retrospectively, the authors evaluated the prevalence and possible cause of liver glycogen accumulation in such patients.

METHODS

The authors searched the files of the Division of Pathology at Cincinnati Children's Hospital from 1975 and 2004 for cases of urea cycle enzyme defects and identified 11 patients who had had liver biopsy performed and/or liver transplantation. All patients were on diets containing essential amino acids as the protein source before liver biopsy and/or transplantation.

RESULTS

All but one patient had focal or diffuse glycogen accumulation in hepatocytes in at least one specimen by light microscopic examination. Two young infants also had cholestasis. Electron microscopy performed on six patients showed diffuse or focal glycogen excess in the cytoplasm of individual hepatocytes. Biochemical studies of three patients revealed two with hepatic glycogen content in the upper normal range and one that was abnormally high. Glycolytic enzyme activities were normal in two patients, and one patient had low phosphorylase activity.

CONCLUSIONS

Hepatocyte glycogen accumulation in urea cycle enzyme defects resembles that seen in glycogen storage disease but can be distinguished in most cases by non-uniformity of distribution and/or the absence of sinusoidal compression by expanded hepatocytes. We speculate that therapeutic modification of dietary protein content by restriction to essential amino acids, including leucine, may promote glycogen accumulation by increasing insulin secretion.

Plasminogen regulates pro-opiomelanocortin processing

BACKGROUND

Plasminogen-deficient mice exhibit behavioral differences in response to stress, including a markedly reduced acoustic startle reflex response compared with wild-type (WT) littermates. The acoustic startle reflex activates the hypothalamic-pituitary axis and is modulated by these hormones.

OBJECTIVES

The purpose of this study was to investigate whether plasminogen plays a role in the processing of hormones in the hypothalamic-pituitary axis.

METHODS

In this study the concentration of plasma, pituitary, and brain hypothalamic-pituitary axis hormones and precursor processing was examined in WT and plasminogen deficient (Plg-/-) mice before and after acoustic startle reflex testing.

RESULTS

Plasma adrenocorticotropic hormone (ACTH), beta-endorphin and alpha-melanocyte stimulating hormone were elevated after acoustic startle reflex testing in both WT and (Plg-/-) mice. However, in the Plg-/- mice, beta-endorphin values were 43, 35, and 45% lower in the plasma, pituitary, and whole brain, respectively, compared with the WT mice. Plasmin readily degraded precursor peptides, the 23-kDa precursor, beta-lipotropin, and ACTH, when presented as purified proteins or as the secretory products of mouse pituitary cells (AtT-20). The precursor peptide, 23 kDa, for beta-endorphin and alpha-melanocyte stimulating hormone was reduced in the pituitaries from the Plg-/- mice, and the mRNA for Plg was found in pituitaries from WT mice. Infusion of beta-endorphin and alpha-melanocyte stimulating hormone into the brain of Plg-/- mice increased acoustic startle reflex.

CONCLUSIONS

The results of this study show that plasmin is involved in the processing of hormones derived from the pro-opiomelanocortin precursor in the intermediate pituitary. A deficiency of plasminogen reduces processing of beta-endorphin and alpha-melanocyte stimulating hormone, and interferes with normal brain function.

Hepatitis B: how many patients are counselled on transmission prevention and how many contacts are offered vaccination?

The proportion of cases of hepatitis B who receive counselling on how to prevent transmission and for whom at-risk contacts are offered vaccination is low. A centralised arrangement under the management of the local CCDC can provide a comprehensive contract tracing service.

Endometrial bleeding in hormone replacement therapy users: preliminary findings regarding the role of matrix metalloproteinase 9 (MMP-9) and tissue inhibitors of MMPs

OBJECTIVE

To establish the effect of hormone replacement therapy (HRT) on the expression of matrix metalloproteinase 9 (MMP-9) and the tissue inhibitor of MMPs, TIMP-1, in the endometrium of postmenopausal and perimenopausal women.

DESIGN

Prospective observational study.

SETTING

United Kingdom teaching hospital.

PATIENT(S)

Thirty-one perimenopausal and postmenopausal HRT recipients, with a control group of eight postmenopausal women not undergoing HRT.

INTERVENTION(S)

Prospective record of bleeding patterns and endometrial biopsy.

MAIN OUTCOME MEASURE(S)

Endometrial histology, bleeding patterns, MMP-9, and TIMP-1 expression.

RESULT(S)

MMP-9 and TIMP-1 are expressed in benign postmenopausal endometrium. Expression of both molecules is reduced in HRT recipients compared with non-HRT recipients.

CONCLUSION(S)

Exposure to HRT appears to alter endometrial expression of MMP-9 and TIMP-1 and also the local balance between these molecules. This alteration may promote breakdown of the endometrial extracellular matrix and blood vessels and hence bleeding.

Commissioning--a postal questionnaire survey of the opinions of GPs and public health physicians in Wales

A survey of general practitioners (GPs) and public health physicians (PHPs) in Wales was carried out to establish opinions on a range of matters concerning health care commissioning. Eighty-eight GPs and 46 PHPs were posted questionnaires, with responses received from 56 GPs and 40 PHPs. The results showed good support for the separation of the purchasing and providing roles of health management but little for the internal market or fundholding.

Analysis of 1263 deaths in four general practices

BACKGROUND

The death of a patient is a significant event that occurs often enough in general practice for it to have the potential to tell us much about the care we provide. There are few large series in the literature and we still know little about the collaborative use of this outcome measure.

AIM

To determine the pattern of deaths and potentially preventable factors in our practices.

METHOD

We completed a standard data collection form after each death in four general practices over a 40-month period. The results were discussed at quarterly meetings.

RESULTS

A total of 1263 deaths occurred among our registered patients during the period of the audit. Preventable factors contributing to deaths were considered to be attributable to: patients (40%): mainly cigarette smoking, poor compliance, and alcohol problems; general practice teams (5%): mainly delayed referral, diagnosis and treatment, and failure to prescribe aspirin to patients with vascular disease; hospitals (6%): mainly delayed diagnosis and perceived treatment problems; the environment (3%): mainly falls, principally resulting in fractured neck of femur.

CONCLUSION

A simple audit of deaths along the lines that we describe gives important information about the care provided by general practice teams and those in hospital practice. It has both educational value and is a source of ideas for service improvement and further study, particularly when carried out over several years.