Mortality from Listeria monocytogenes meningoencephalitis following escalation to alemtuzumab therapy for relapsing-remitting Multiple Sclerosis.

We report the case of a patient who died from the rare complication of Listeriosis in the immediate phase following alemtuzumab administration one month after discontinuing dimethyl fumarate (DMF). There is considerable overlap with typical post-infusion symptoms therefore high surveillance and low threshold for empirical or possible prophylactic antibiotic therapy is advocated.

Production of null mutants in the major intestinal esterase gene (ges-1) of the nematode Caenorhabditis elegans.

The ges-1 gene of the nematode Caenorhabditis elegans codes for a nonspecific carboxylesterase that is expressed only in the intestinal lineage. This esterase has turned out to be a convenient biochemical marker for lineage-specific differentiation. In the present paper, we describe the production of several C. elegans strains that lack detectable activity of the ges-1 esterase. To isolate these ges-1 null strains, we first produced a strain of hermaphrodites in which the wild-type copy of the ges-1 gene was stably balanced over a previously isolated isoelectric focusing allele, ges-1(ca6); this parental strain was then mutagenized with EMS and isoelectric focusing gels were used to identify progeny populations that lacked either ges-1(+) or ges-1(ca6) esterase activity. This method is a straightforward and general approach to obtaining null mutations in any gene that has a biochemical or immunological assay. The ges-1 gene is not essential to worm survival, development or reproduction. Furthermore, lack of the ges-1 product has no obvious effect on the ability of worms (containing either normal or greatly reduced levels of acetylcholinesterases) to survive exposure to esterase inhibitors. The ges-1 gene product provides roughly half of the total esterase activity measured in crude extracts of L1 larvae or mixed worm populations. However, histochemical staining of individual ges-1(0) embryos shows that the ges-1 esterase is the first and essentially the only esterase to be produced during embryonic development, from the midproliferation phase up to at least the twofold stage of morphogenesis. These ges-1(0) strains now allow us to investigate the developmental control of the ges-1 gene by DNA-mediated transformation, in which the ges-1 gene acts as its own reporter.

Insulin sensitivity, glucose effectiveness, and body fat distribution pattern in nondiabetic offspring of patients with NIDDM.

OBJECTIVE: To determine the relationship of insulin sensitivity (SI), glucose effectiveness (glucose-dependent glucose transport [SG]), and body fat distribution patterns in glucose-tolerant offspring of patients with non-insulin-dependent diabetes mellitus (NIDDM). RESEARCH DESIGN AND METHODS: Ten glucose-tolerant offspring of patients with NIDDM and 10 age-, sex-, and weight-matched healthy control subjects without family history of diabetes were studied with the minimal model method of Bergman et al. Body fat composition and distribution pattern were assessed by the bioelectrical impedance analyzer and waist-hip circumference ratios (WHR), respectively, in each subject. RESULTS: Mean fasting serum glucose (4.39 +/- 0.17 vs. 3.94 +/- 0.17 mM) and postglucose peak (18.50 +/- 1.50 vs. 13.20 +/- 1.06 mM) levels were significantly greater (P less than 0.05) in the offspring than in the control subjects. Mean fasting serum insulin levels were slightly greater but not significantly different in the offspring versus control subjects (64 +/- 14 vs. 29 +/- 7 pM). After intravenous stimulation with glucose and tolbutamide, the mean serum insulin rose to significantly greater (P less than 0.05) levels at t = 5 and 25 min in the offspring compared with the control subjects. Mean SI was significantly reduced by 45% in the offspring compared with the control subjects (4.77 +/- 0.67 vs. 8.37 +/- 1.24 x 10(-4) min-1.mU-1.L-1). However, SG was not different in the offspring versus control subjects (1.92 +/- 0.12 vs. 2.10 +/- 0.17 x 10(-2) min-1). SI correlated significantly and inversely with the percentage of body fat mass (r = -0.580, P less than 0.05) but not with the WHR (r = -0.019) in the offspring. We found a negative association between SI and basal serum insulin (r = -0.798, P less than 0.01) but not with the poststimulation incremental insulin responses in the offspring. Family history of diabetes independently accounted for at least 27% of variance in the SI in our subjects. CONCLUSIONS: Our study confirmed that insulin insensitivity but not a reduced glucose effectiveness exists in young glucose-tolerant offspring of patients with NIDDM. The reduced S1 appears to be causally related to the total body fat content and may be a familial and/or genetic trait in the offspring.

Serum insulin and glucose concentrations in people at risk for type II diabetes. A comparative study of African Americans and Nigerians.

OBJECTIVE: To examine the phases of acute insulin release and glucose homeostasis in people of African descent with and without a positive family history of type II diabetes who reside in geographically diverse environments. The prevalence of type II diabetes in people of African descent varies considerably depending on the country of habitat. Family history is recognized as an important risk factor for the development of the disease. RESEARCH DESIGN AND METHODS: We studied serum glucose and insulin concentrations--before and after intravenous glucose challenge--in glucose-tolerant, first-degree relatives of African-American (n = 18) and Nigerian (n = 20) type II diabetic patients and their respective healthy control subjects (African American, n = 9; Nigerian, n = 18) living in their native countries. The acute first- (t = 0-5 min) and second-phase (t = 10-60 min) insulin releases were calculated as the sum of incremental insulin responses to the intravenous glucose stimulation. RESULTS: Mean serum glucose levels and glucose decay constant (KG) were not different in the African Americans and Nigerians. Fasting serum insulin in the African-American relatives was significantly greater than the Nigerian relatives (16.0 +/- 3.0 vs. 5.8 +/- 1.7 mU/L, P < 0.05). In contrast, FSI levels in the African-American control subjects were similar to Nigerian control subjects (6.3 +/- 1.4 vs. 4.5 +/- 1.8 mU/L). Acute first- and second-phase insulin levels were 2-3 times (P < 0.01) greater in African Americans than Nigerians, irrespective of family history of diabetes. Comparing the African-American relatives with healthy control subjects, we found significantly (P < 0.05) higher FSI in the relatives; whereas the acute first- (272 +/- 44 vs. 222 +/- 55 mU/L) and second-phase (388 +/- 61 vs. 235 +/- 53 mU/L) serum insulin release tended to be greater, but not significantly different in the relatives. In contrast, the acute first (101 +/- 15 vs. 120 +/- 20 mU/L) and second phase (88 +/- 14 vs. 111 +/- 17 mU/l) of insulin release were slightly lower, but not significantly different, in the Nigerian relatives versus the Nigerian healthy control subjects. In a subgroup of nonobese African-American (n = 11) and Nigerian (n = 11) relatives, and African-American (n = 8) and Nigerian (n = 7) healthy control subjects with a body mass index < 30 kg/m2, the mean fasting and post-stimulation serum glucose were not different. However, serum insulin concentrations in the African Americans were significantly different from those of the Nigerians. The pattern of insulin responses in the nonobese subjects was similar to those of the respective African-American and Nigerian groups. CONCLUSIONS: Our preliminary study demonstrates greater serum insulin responses and, perhaps, insulin resistance in glucose-tolerant African Americans than in their Nigerian counterparts, irrespective of family history of diabetes and obesity. We conclude that the antecedent lesions leading to the development of type II diabetes may be different in the first-degree relatives of African-American and Nigerian diabetic patients.

Multimodal neurophysiological evaluation of primary progressive multiple sclerosis - An increasingly valid biomarker, with limits.

BACKGROUND: The promising utility of multi-modality evoked potential batteries to objectively measure multi-tract dysfunction has been evaluated by several groups using different methods. OBJECTIVE: To independently evaluate the use of multi-modality evoked potential batteries as surrogate biomarkers for both physical and cognitive status in a cohort of Primary Progressive Multiple Sclerosis patients and identify the most potentially useful scoring method of those described. METHODS: 28 Patients with Primary Progressive Multiple Sclerosis underwent clinical evaluation with Kurtzke's Modified EDSS and the Multiple Sclerosis Functional Composite (MSFC). 19 Participants also underwent the Minimal Assessment of Cognitive Function in Multiple Sclerosis. Visual, Brainstem Auditory, Somatosensory and Motor Evoked Potentials were recorded on all. Results were graded by variants of the Global Evoked Potential Score, Multiple Evoked Potential Score and Summation of Z transformed Evoked Potential Latencies for correlation against the clinical scores. CONCLUSIONS: Multi-modal evoked potential batteries generally show moderate and useful correlation with clinical status as measured by the regulatory standard of EDSS (r = .65 vs. mEPS p < .005) and MSFC (r = .39 vs. mEPS p < .05). The graded qualitative mEPS scoring system displayed the strongest relationship although the influence of scoring system applied appeared reassuringly minimal. Non-association with cognitive impairment is an important limitation however.

Neuropathological and histochemical changes in a multiple mitochondrial DNA deletion disorder.

The identification of cytochrome c oxidase (COX)-deficient/succinate dehydrogenase (SDH)- positive cells using sequential histochemistry has proved important in the identification of cells with high mitochondrial DNA (mtDNA) mutant load. We demonstrate large numbers of COX-deficient/SDH-positive neurons in a mosaic pattern throughout the CNS of a patient with a multiple mtDNA deletion disorder. This patient had prominent central and peripheral nervous system involvement with marked cerebellar ataxia, a parkinsonian extra-pyramidal movement disorder, external ophthalmoplegia, dysphagia, and a severe peripheral neuropathy. There was degeneration of myelin tracts in the cerebellum and dorsal spinal columns, diffuse astrocytosis, and selective neuronal degeneration particularly in the midbrain and cerebral microvacuolation. The proportional distribution of the COX-deficient neurons did not always correlate directly with the degree of neuropathological damage with regions of high neuronal loss having relatively low proportions of these cells. Other clinically affected CNS regions have high levels of COX-deficient neurons without significant cell loss. The role of these COX-deficient neurons in causing neuronal degeneration and clinical symptoms is discussed.

Normalization of insulin sensitivity and glucose homeostasis in type I diabetic pancreas transplant recipients: a 48-month cross-sectional study--a clinical research center study.

Despite the establishment of heterotopic, whole cadaveric, pancreas-kidney transplantation as an effective form of therapy for type I diabetes with chronic renal insufficiency, uncertainty remains regarding the potentially deleterious effects of severe peripheral hyperinsulinemia and long-term immunosuppressive therapy on insulin sensitivity (SI) and, subsequently, on beta-cell function and maintenance of euglycemia over years. To examine the alterations in SI that may occur over time and their impact on glucose homeostasis, beta-cell function, SI, and glucose effectiveness (SG) were measured using the frequently sampled iv glucose tolerance test (FSIGTT) and minimal model method in 39 glucose-tolerant type I diabetic pancreas-kidney transplant recipients in a cross-sectional manner at 3, 6, 12, 24, 36, and 48 months post transplantation. Mean basal and poststimulation (oral glucose tolerance test and FSIGTT) serum glucose responses were similar among the groups from 3-48 months. Plasma insulin response during the FSIGTT was higher (P < 0.001, repeated measures ANOVA) at 6 months vs. 12-48 months. Incremental integrated areas under the curve for 1st phase, glucose-stimulated, tolbutamide-stimulated, and total insulin responses tended to be higher (P = NS) at 6 months. Glucose disappearance rate constant, kG, did not differ significantly from 3-48 months. Mean +/- SE S1 in the pancreas-kidney recipients was 4.25 +/- 1.6 x 10(-4) min-1/microU.mL-1 at 3 months (group 1, n = 7) (vs. 7.9 +/- 0.9 x 10(-4) normal reference), decreased to 2.95 +/- 0.6 at 6 months (group 2, n = 11), improved to baseline values of 4.6 +/- 1.0 at 12 months (group 3, n = 10), and normalized at 24 months (group 4, n = 6) to 7.5 +/- 1.7 (P = 0.008). The normalisation in SI was sustained at 36 months (group 5, n = 3, 8.0 +/- 3.7, P = 0.03), and up to 48 months (group 6, n = 5, 6.1 +/- 1.6, P = 0.04) in the type I diabetic pancrease allograft recipients. Corresponding SG tended to increase but did not differ significantly from 3 (1.69 +/- 0.2 x 10(-2)/min), 6 (2.33 +/- 0.39), 12 (1.9 +/- 0.2), 24 (1.9 +/- 0.4), 36 (1.98 +/- 0.15), and 48 months (2.27 +/- 0.3). Hepatic insulin extraction did not differ among the groups. SI correlated significantly with prednisone dose (r = -0.45, P = 0.002). In summary, after successful whole cadaveric, heterotopic, pancreas-kidney transplantation in type I diabetic recipients: 1) euglycemia remains relatively stable over 48 months; 2) SI is diminished early after transplantation (3-6 months), possibly caused by the effects of initially high doses of prednisone and hyperinsulinemia. However, this is compensated by a normal SG and by hyperinsulinemia to maintain euglycemia; 3) SI improves by 12 months and normalizes from 24-48 months, after transplantation, despite hyperinsulinemia and long-term immunosuppressive therapy. The time-dependent decrease in poststimulation insulin response after successful pancreas-kidney transplantation in type I diabetic recipients, therefore, is not caused by gradual beta-cell decline but rather is a response to normalization of SI. However, longitudinal studies pre-and post pancreas transplantation over an extended period of time will be necessary to confirm the present findings.

Differences in basal and poststimulation glucose homeostasis in nondiabetic first degree relatives of black and white patients with type 2 diabetes mellitus.

Black Americans (blacks) have a higher prevalence and earlier onset of type 2 diabetes than white Americans (whites). To examine metabolic differences in both races, we measured the basal glucose turnover rates (D-]3-3H]glucose technique) and plasma glucose, insulin, and C-peptide levels before and after an oral glucose load in 24 glucose-tolerant black and 14 white female relatives of patients with type 2 diabetes. Eight black and 8 white female subjects with no family history of diabetes served as controls. Mean fasting and postglucose plasma glucose levels were not significantly different between the black and white relatives and the control subgroups. Mean fasting plasma insulin and C-peptide levels were slightly greater but not significantly different between the relatives. After oral glucose ingestion, mean incremental integrated plasma insulin areas were significantly (P less than 0.02) greater in the black than the white relatives (70 +/- 14 vs. 29 +/- 6 nM.min). In addition, incremental integrated C-peptide areas were greater in the black than the white relatives (303 +/- 55 vs. 115 +/- 33; P less than 0.005). Similarly, we found significantly greater integrated incremental insulin (61 +/- 11 vs. 22 +/- 3 nM.min; P less than 0.02) and C-peptide (248 +/- 58 vs. 47 +/- 16; P less than 0.005) areas in the black than the white controls, respectively. The estimated basal and postglucose hepatic insulin extraction values, expressed as molar ratios of C-peptide and insulin, were not significantly different between the relatives. While basal hepatic insulin extraction was significantly (P less than 0.05) lower in the black controls, the postprandial insulin clearance was not different between the black and white controls. Mean basal hepatic glucose production was greater (P less than 0.02) in the black than the white relatives (2.49 +/- 0.13 vs. 2.02 +/- 0.12 mg/kg.min). Similarly, the black controls had greater hepatic glucose production than the white controls (2.36 +/- 0.15 vs. 1.81 +/- 0.08 mg/kg.min; P less than 0.001). We conclude that basal and poststimulation glucose homeostatic regulation appear to be different in black and white females, regardless of family history of type 2 diabetes.

Cytochrome c oxidase deficient cells accumulate in the hippocampus and choroid plexus with age.

The chronological accumulation of mitochondrial dysfunction has been proposed as a potential mechanism in the physiological processes of aging. Cytochrome c oxidase deficient, succinate dehydrogenase positive muscle fibers containing high copy numbers of a mitochondrial DNA mutation are a pathological hallmark of mitochondrial DNA disorders. We show that there is an age-related increase in cytochrome c oxidase-deficient cells in both hippocampal pyramidal neurons and choroid plexus epithelial cells. We suggest that these cells contribute to the cell death and dysfunction in CNS aging.

Mitochondrial enzyme-deficient hippocampal neurons and choroidal cells in AD.

OBJECTIVE: To determine whether hippocampal neurons and choroidal epithelial cells demonstrate a mitochondrial enzyme deficiency in AD more frequently than in normal aging. BACKGROUND: High levels of mutant mitochondrial DNA (mtDNA) cause a deficiency in cytochrome c oxidase (COX) (complex IV activity) because three of its 13 subunits are encoded for by mtDNA. In contrast, succinate dehydrogenase (SDH) (complex II activity) remains intact because all of its subunits are nuclear encoded. The histologic hallmark of cells containing high levels of mtDNA mutation in both primary mtDNA disorders and normal aging muscle is the presence of COX-deficient SDH-positive cells. METHODS: The authors applied a sequential histochemical method for COX and SDH to hippocampal sections in 17 AD and 17 age-matched control brains. This confers the advantages of both looking at individual cells in situ and measuring the actual mitochondrial complex activity rather than simply the complex quantity. RESULTS: COX-deficient SDH-positive hippocampal neurons and choroidal epithelial cells are more prevalent in patients with AD than in controls. In addition the COX-deficient SDH-positive choroidal cells are associated with an enlargement in size. CONCLUSION: This increase in number of COX-deficient SDH-positive hippocampal pyramidal neurons and choroid epithelial cells provides strong evidence that a substantial mitochondrial enzyme activity defect occurs in individual cells more frequently in AD than in normal aging and that mitochondria may play a significant role in the pathogenesis of AD.

Mitochondrial DNA mutations in disease and ageing.

The chronological accumulation of mitochondrial DNA mutations has been proposed as a potential mechanism in the physiological processes of ageing and age-related disease. We discuss the evidence behind this theory and relate some of the ageing mitochondrial changes to mitochondrial DNA disorders. In particular, we describe the aggregation of cytochrome c oxidase-deficient cells in both skeletal muscle and the CNS in normal ageing as seen in the mitochondrial DNA disorders. These mitochondrial enzyme-deficient cells have been shown to occur in significant quantities in both muscle and CNS in patients with mitochondrial DNA disorders. In both ageing and mtDNA disorder muscle these cytochrome c-deficient fibres contain high levels of a single mutant strain of mitochondrial DNA. Whether these mutations are a primary or secondary event in the physiology of ageing remains to be determined.

Role of mitochondrial DNA mutations in disease and aging.

Since Harman in 1972 first proposed a role in the process of aging for the mitochondrial genome, a wealth of evidence has been accumulated to support this theory. We discuss the hereditary mitochondrial DNA disorders, which we believe may give insight into both normal aging and neurodegenerative conditions. We then review the evidence for the role of mitochondrial DNA mutations in both aging and age-related disorders and also discuss new approaches for investigating the mitochondrial genome at a single cell level, by observing the activity of the mitochondrial enzyme cytochrome c oxidase.

Neurochemical and electrophysiological studies on FR115427, a novel non-competitive NMDA receptor antagonist.

The pharmacological profile of FR115427 has been examined using ligand binding and electrophysiological techniques. Binding of [3H]dizocilpine in the presence of L-glutamate was inhibited by the (+) isomers of dizocilpine and FR115427. The corresponding (-) isomers were less active, and stereoselectivity was particularly marked in the case of FR115427. In contrast to dizocilpine, the affinity of FR115427 for [3H]dizocilpine binding sites was little affected by addition of either L-glutamate and/or glycine. In a cortical wedge preparation, FR115427 inhibited N-methyl-D-aspartate (NMDA)-induced responses in a non-competitive, use-dependent manner. Intracellularly recorded excitatory synaptic responses in hippocampal neurones were only partially inhibited by FR115427 thereby confirming a selective effect on the NMDA-mediated component of neuronal excitation induced by the endogenous neurotransmitter. The data suggest that FR115427 is a non-competitive, use-dependent NMDA receptor antagonist with more pronounced stereoselectivity and less marked use dependence than dizocilpine.

Glucose and insulin responses to intravenous glucose challenge in relatives of Nigerian patients with non-insulin-dependent diabetes mellitus.

We analysed blood insulin and glucose concentrations before and during frequently sampled intravenous glucose tolerance tests (FSIGT) in 2 groups of Nigerian subjects: (A) Control group (n = 18), without a positive family history of diabetes mellitus, and (B) Experimental group (n = 16), comprising age-, sex- and body mass-matched first-degree relatives of patients with non-insulin-dependent diabetes mellitus (NIDDM). In comparison with Group A subjects, those in Group B had: (i) higher fasting plasma glucose level (mean +/- S.E.M. 4.1 +/- 0.1 vs. 3.8 +/- 0.11 mmol/l, P < 0.05); (ii) similar fasting serum insulin levels (6.7 +/- 5.0 vs. 5.8 +/- 5.6 mU/l, P = NS); (iii) lower mean incremental area under the first-phase (t = 0-10 min) post-glucose challenge insulin curve (376.9 +/- 8.8 vs. 435.6 +/- 5.6 mU/min l-1, P < 0.05); (iv) increased incremental area under the second-phase (t = 10-182 min) post-glucose challenge insulin curve (432.9 +/- 11.5 vs. 161.3 +/- 8.7 mU/min l-1, P < 0.05); (v) reduced KG rate constant of glucose elimination (0.97 +/- 0.12 vs. 1.41 +/- 0.12%/min, P < 0.05). These results suggest that the subjects with a positive family history of NIDDM have a reduced beta-cell insulin secretory reserve (from reduced first-phase insulin response), tendency to rebound hyperinsulinemia during the latter phase of the insulin secretory response, a degree of tissue insulin insensitivity (as evident from high fasting plasma glucose despite similar insulin levels) and a diminished glucose disposal rate, in comparison with subjects without a family history of NIDDM. These features predict subsequent development of diabetes and suggest that as in Caucasians, first-degree relatives of Nigerian patients with NIDDM are at greater risk for future development of the disease.

17 alpha-hydroxylase deficiency masquerading as primary hyperaldosteronism.

A unique case of 17 alpha-hydroxylase deficiency with steroid-responsive primary hyperaldosteronism is reported. Initially the patient was misdiagnosed as testicular feminization for 16 years and was thought to have typical primary hyperaldosteronism for 5 years. However, careful detailed endocrine studies showed markedly elevated progesterone, deoxycorticosterone, and 18-hydroxycorticosterone values with low levels of 17-hydroxyprogesterone, 11-deoxycortisol, testosterone, and DHEA-Sulfate. In contrast to the suppressed aldosterone levels that are found in 17 alpha-hydroxylase deficiency, this patient's aldosterone levels were inappropriately elevated before and after ACTH stimulation. Use of glucocorticoid replacement resolved the patient's symptoms and completely corrected the hypokalemia and hypertension. In summary, recognition of 17 alpha-hydroxylase deficiency with steroid-responsive primary hyperaldosteronism is important because hypertension, hypokalemia, and symptoms respond to steroid replacement.

Orofacial lipomas diagnosed by CT and MRI.

Oral lipomas buried deep in soft tissues can be difficult to diagnose clinically. Computed tomography or magnetic resonance imaging can aid the diagnosis of this rare oral lipoma.