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1.  ST6Gal-I expression in ovarian cancer cells promotes an invasive phenotype by altering integrin glycosylation and function 
Background
Ovarian adenocarcinoma is not generally discovered in patients until there has been widespread intraperitoneal dissemination, which is why ovarian cancer is the deadliest gynecologic malignancy. Though incompletely understood, the mechanism of peritoneal metastasis relies on primary tumor cells being able to detach themselves from the tumor, escape normal apoptotic pathways while free floating, and adhere to, and eventually invade through, the peritoneal surface. Our laboratory has previously shown that the Golgi glycosyltransferase, ST6Gal-I, mediates the hypersialylation of β1 integrins in colon adenocarcinoma, which leads to a more metastatic tumor cell phenotype. Interestingly, ST6Gal-I mRNA is known to be upregulated in metastatic ovarian cancer, therefore the goal of the present study was to determine whether ST6Gal-I confers a similarly aggressive phenotype to ovarian tumor cells.
Methods
Three ovarian carcinoma cell lines were screened for ST6Gal-I expression, and two of these, PA-1 and SKOV3, were found to produce ST6Gal-I protein. The third cell line, OV4, lacked endogenous ST6Gal-I. In order to understand the effects of ST6Gal-I on cell behavior, OV4 cells were stably-transduced with ST6Gal-I using a lentiviral vector, and integrin-mediated responses were compared in parental and ST6Gal-I-expressing cells.
Results
Forced expression of ST6Gal-I in OV4 cells, resulting in sialylation of β1 integrins, induced greater cell adhesion to, and migration toward, collagen I. Similarly, ST6Gal-I expressing cells were more invasive through Matrigel.
Conclusion
ST6Gal-I mediated sialylation of β1 integrins in ovarian cancer cells may contribute to peritoneal metastasis by altering tumor cell adhesion and migration through extracellular matrix.
doi:10.1186/1757-2215-1-3
PMCID: PMC2584051  PMID: 19014651
2.  Diagnostic Validity of Age- And Education-Corrections for the Mini-Mental State Examination (MMSE) in African American Elders 
Objectives
To investigate whether demographic (age and education) adjustments for the Mini-Mental State Examination (MMSE) attenuate mean score discrepancies between African American and Caucasian adults, and to determine whether demographically-adjusted MMSE scores improve the diagnostic classification accuracy of dementia in African American adults when compared to unadjusted MMSE scores.
Design
Cross-sectional study.
Setting
Community-dwelling adults participating in the Mayo Clinic Alzheimer’s Disease Patient Registry (ADPR) and Alzheimer’s Disease Research Center (ADRC).
Participants
Three thousand two hundred fifty-four adults (2819 Caucasian, 435 African American) aged 60 and older.
Measurements
MMSE at study entry.
Results
African American adults obtained significantly lower unadjusted MMSE scores (23.0 ± 7.4) compared to Caucasian adults (25.3 ± 5.4). This discrepancy persisted despite adjustment of MMSE scores for age and years of education using established regression weights or newly-derived weights. However, controlling for dementia severity at baseline and adjusting MMSE scores for age and quality of education attenuated this discrepancy. Among African American adults, an age- and education-adjusted MMSE cut score of 23/24 provided optimal dementia classification accuracy, but this represented only a modest improvement over an unadjusted MMSE cut score of 22/23. The posterior probability of dementia in African American adults is presented for various unadjusted MMSE cut scores and prevalence rates of dementia.
Conclusion
Age, dementia severity at study entry, and quality of educational experience are important explanatory factors to understand the existing discrepancies in MMSE performance between Caucasian and African American adults. Our findings support the use of unadjusted MMSE scores when screening African American elders for dementia, with an unadjusted MMSE cut score of 22/23 yielding optimal classification accuracy.
doi:10.1111/j.1532-5415.2011.03766.x
PMCID: PMC3288600  PMID: 22150301
MMSE; African American; ethnicity; dementia; cognition
3.  Difficulty and Discrimination Parameters of Boston Naming Test Items in a Consecutive Clinical Series 
The Boston Naming Test is one of the most widely used neuropsychological instruments; yet, there has been limited use of modern psychometric methods to investigate its properties at the item level. The current study used Item response theory to examine each item's difficulty and discrimination properties, as well as the test's measurement precision across the range of naming ability. Participants included 300 consecutive referrals to the outpatient neuropsychology service at Mayo Clinic in Florida. Results showed that successive items do not necessarily reflect a monotonic increase in psychometric difficulty, some items are inadequate to distinguish individuals at various levels of naming ability, multiple items provide redundant psychometric information, and measurement precision is greatest for persons within a low-average range of ability. These findings may be used to develop short forms, improve reliability in future test versions by replacing psychometrically poor items, and analyze profiles of intra-individual variability.
doi:10.1093/arclin/acr042
PMCID: PMC3142950  PMID: 21593059
Boston Naming Test; Item response theory; Item difficulty; Item discriminability
4.  Immune interactions in endometriosis 
Endometriosis is a common, complex gynecologic disorder characterized by the presence of endometrial glands and stroma at extrauterine (ectopic) sites. In women who develop this disease, alterations in specific biological processes involving both the endocrine and immune systems have been observed, which may explain the survival and growth of displaced endometrial tissue in affected women. In the past decade, a considerable amount of research has implicated a role for alterations in progesterone action at both eutopic and ectopic sites of endometrial growth which may contribute to the excessive inflammation associated with progression of endometriosis; however, it remains unclear whether these anomalies induce the condition or are simply a consequence of the disease process. In this article, we summarize current knowledge of alterations within the immune system of endometriosis patients and discuss how endometrial cells from women with this disease not only have the capacity to escape immunosurveillance, but also use inflammatory mechanisms to promote their growth within the peritoneal cavity. Finally, we discuss evidence that exposure to an environmental endocrine disruptor, such as 2,3,7,8-tetrachlorodibenzo-p-dioxin, can mediate the development of an endometrial phenotype that exhibits both reduced progesterone responsiveness and hypersensitivity to proinflammatory stimuli mimicking the endometriosis phenotype. Future studies in women with endometriosis should consider whether a heightened inflammatory response within the peritoneal microenvironment contributes to the development and persistence of this disease.
doi:10.1586/eci.11.53
PMCID: PMC3204940  PMID: 21895474
chemokines; cytokines; dioxin; endocrine-disrupting chemicals; endometriosis; estrogen; immune–endocrine interactions; inflammation; peritoneum; progesterone; TCDD
5.  Validation of the Mayo Sleep Questionnaire to Screen for REM Sleep Behavior Disorder in an Aging and Dementia Cohort 
Sleep medicine  2011;12(5):445-453.
Objective
To validate a questionnaire focused on REM sleep behavior disorder (RBD) among participants in an aging and dementia cohort.
Background
RBD is a parasomnia that can develop in otherwise neurologically-normal adults as well as in those with a neurodegenerative disease. Confirmation of RBD requires polysomnography (PSG). A simple screening measure for RBD would be desirable for clinical and research purposes.
Methods
We had previously developed the Mayo Sleep Questionnaire (MSQ), a 16 item measure, to screen for the presence of RBD and other sleep disorders. We assessed the validity of the MSQ by comparing the responses of patients’ bed partners with the findings on PSG. All subjects recruited in the Mayo Alzheimer’s Disease Research Center at Mayo Clinic Rochester and Mayo Clinic Jacksonville from 1/00 to 7/08 who had also undergone a PSG were the focus of this analysis.
Results
The study sample was comprised of 176 subjects [150 male; median age 71 years (range 39–90)], with the following clinical diagnoses: normal (n=8), mild cognitive impairment (n=44), Alzheimer’s disease (n=23), dementia with Lewy bodies (n=74), as well as other dementia and/or parkinsonian syndromes (n=27). The core question on recurrent dream enactment behavior yielded a sensitivity (SN) of 98% and specificity (SP) of 74% for the diagnosis of RBD. The profile of responses on four additional subquestions on RBD and one on obstructive sleep apnea improved specificity.
Conclusions
These data suggest that among aged subjects with cognitive impairment and/or parkinsonism, the MSQ has adequate SN and SP for the diagnosis of RBD. The utility of this scale in other patient populations will require further study.
doi:10.1016/j.sleep.2010.12.009
PMCID: PMC3083495  PMID: 21349763
sleep disorders; parasomnias; dementia; Alzheimer’s disease; dementia with Lewy bodies; parkinsonism
6.  Association of common KIBRA variants with episodic memory and AD risk 
Neurobiology of aging  2010;32(3):557.e1-557.e9.
KIBRA SNP rs17070145 was identified in a GWAS of memory performance, with some but not all follow-up studies confirming association of its T allele with enhanced memory. This allele was associated with reduced Alzheimer's disease (AD) risk in one study, which also found overexpression of KIBRA in memory-related brain regions of ADs. We genotyped rs17070145 and 14 additional SNPs in 2571 LOADs vs. 2842 controls, including African-Americans. We found significantly reduced risk for rs17070145 T allele in the older African-American subjects (p=0.007) and a suggestive effect in the older Caucasian series. Meta-analysis of this allele in >8000 subjects from our and published series showed a suggestive protective effect (p=0.07). Analysis of episodic memory in control subjects did not identify associations with rs17070145, though other SNPs showed significant associations in one series. KIBRA showed evidence of overexpression in the AD temporal cortex (p=0.06) but not cerebellum. These results suggest a modest role for KIBRA as a cognition and AD risk gene, and also highlight the multifactorial complexity of its genetic associations.
doi:10.1016/j.neurobiolaging.2010.11.004
PMCID: PMC3065956  PMID: 21185624
Alzheimer's disease; Association studies in genetics; Case control studies
7.  Characterization of frontotemporal dementia and/or amyotrophic lateral sclerosis associated with the GGGGCC repeat expansion in C9ORF72 
Brain  2012;135(3):765-783.
Numerous kindreds with familial frontotemporal dementia and/or amyotrophic lateral sclerosis have been linked to chromosome 9, and an expansion of the GGGGCC hexanucleotide repeat in the non-coding region of chromosome 9 open reading frame 72 has recently been identified as the pathogenic mechanism. We describe the key characteristics in the probands and their affected relatives who have been evaluated at Mayo Clinic Rochester or Mayo Clinic Florida in whom the hexanucleotide repeat expansion were found. Forty-three probands and 10 of their affected relatives with DNA available (total 53 subjects) were shown to carry the hexanucleotide repeat expansion. Thirty-six (84%) of the 43 probands had a familial disorder, whereas seven (16%) appeared to be sporadic. Among examined subjects from the 43 families (n = 63), the age of onset ranged from 33 to 72 years (median 52 years) and survival ranged from 1 to 17 years, with the age of onset <40 years in six (10%) and >60 in 19 (30%). Clinical diagnoses among examined subjects included behavioural variant frontotemporal dementia with or without parkinsonism (n = 30), amyotrophic lateral sclerosis (n = 18), frontotemporal dementia/amyotrophic lateral sclerosis with or without parkinsonism (n = 12), and other various syndromes (n = 3). Parkinsonism was present in 35% of examined subjects, all of whom had behavioural variant frontotemporal dementia or frontotemporal dementia/amyotrophic lateral sclerosis as the dominant clinical phenotype. No subject with a diagnosis of primary progressive aphasia was identified with this mutation. Incomplete penetrance was suggested in two kindreds, and the youngest generation had significantly earlier age of onset (>10 years) compared with the next oldest generation in 11 kindreds. Neuropsychological testing showed a profile of slowed processing speed, complex attention/executive dysfunction, and impairment in rapid word retrieval. Neuroimaging studies showed bilateral frontal abnormalities most consistently, with more variable degrees of parietal with or without temporal changes; no case had strikingly focal or asymmetric findings. Neuropathological examination of 14 patients revealed a range of transactive response DNA binding protein molecular weight 43 pathology (10 type A and four type B), as well as ubiquitin-positive cerebellar granular neuron inclusions in all but one case. Motor neuron degeneration was detected in nine patients, including five patients without ante-mortem signs of motor neuron disease. While variability exists, most cases with this mutation have a characteristic spectrum of demographic, clinical, neuropsychological, neuroimaging and especially neuropathological findings.
doi:10.1093/brain/aws004
PMCID: PMC3286335  PMID: 22366793
frontotemporal dementia; amyotrophic lateral sclerosis; motor neuron disease; TDP-43; neurogenetics; chromosome 9
8.  Impact of Recently Emerged Sterol 14α-Demethylase (CYP51) Variants of Mycosphaerella graminicola on Azole Fungicide Sensitivity▿ 
Applied and Environmental Microbiology  2011;77(11):3830-3837.
The progressive decline in the effectiveness of some azole fungicides in controlling Mycosphaerella graminicola, causal agent of the damaging Septoria leaf blotch disease of wheat, has been correlated with the selection and spread in the pathogen population of specific mutations in the M. graminicola CYP51 (MgCYP51) gene encoding the azole target sterol 14α-demethylase. Recent studies have suggested that the emergence of novel MgCYP51 variants, often harboring substitution S524T, has contributed to a decrease in the efficacy of prothioconazole and epoxiconazole, the two currently most effective azole fungicides against M. graminicola. In this study, we establish which amino acid alterations in novel MgCYP51 variants have the greatest impact on azole sensitivity and protein function. We introduced individual and combinations of identified alterations by site-directed mutagenesis and functionally determined their impact on azole sensitivity by expression in a Saccharomyces cerevisiae mutant YUG37::erg11 carrying a regulatable promoter controlling native CYP51 expression. We demonstrate that substitution S524T confers decreased sensitivity to all azoles when introduced alone or in combination with Y461S. In addition, S524T restores the function in S. cerevisiae of MgCYP51 variants carrying the otherwise lethal alterations Y137F and V136A. Sensitivity tests of S. cerevisiae transformants expressing recently emerged MgCYP51 variants carrying combinations of alterations D134G, V136A, Y461S, and S524T reveal a substantial impact on sensitivity to the currently most widely used azoles, including epoxiconazole and prothioconazole. Finally, we exploit a recently developed model of the MgCYP51 protein to predict that the substantial structural changes caused by these novel combinations reduce azole interactions with critical residues in the binding cavity, thereby causing resistance.
doi:10.1128/AEM.00027-11
PMCID: PMC3127603  PMID: 21478305
9.  Continuous Three-Dimensional Control of a Virtual Helicopter Using a Motor Imagery Based Brain-Computer Interface 
PLoS ONE  2011;6(10):e26322.
Brain-computer interfaces (BCIs) allow a user to interact with a computer system using thought. However, only recently have devices capable of providing sophisticated multi-dimensional control been achieved non-invasively. A major goal for non-invasive BCI systems has been to provide continuous, intuitive, and accurate control, while retaining a high level of user autonomy. By employing electroencephalography (EEG) to record and decode sensorimotor rhythms (SMRs) induced from motor imaginations, a consistent, user-specific control signal may be characterized. Utilizing a novel method of interactive and continuous control, we trained three normal subjects to modulate their SMRs to achieve three-dimensional movement of a virtual helicopter that is fast, accurate, and continuous. In this system, the virtual helicopter's forward-backward translation and elevation controls were actuated through the modulation of sensorimotor rhythms that were converted to forces applied to the virtual helicopter at every simulation time step, and the helicopter's angle of left or right rotation was linearly mapped, with higher resolution, from sensorimotor rhythms associated with other motor imaginations. These different resolutions of control allow for interplay between general intent actuation and fine control as is seen in the gross and fine movements of the arm and hand. Subjects controlled the helicopter with the goal of flying through rings (targets) randomly positioned and oriented in a three-dimensional space. The subjects flew through rings continuously, acquiring as many as 11 consecutive rings within a five-minute period. In total, the study group successfully acquired over 85% of presented targets. These results affirm the effective, three-dimensional control of our motor imagery based BCI system, and suggest its potential applications in biological navigation, neuroprosthetics, and other applications.
doi:10.1371/journal.pone.0026322
PMCID: PMC3202533  PMID: 22046274
10.  Regulation of Invasive Behavior by Vascular Endothelial Growth Factor is HEF1-dependent 
Oncogene  2010;29(31):4449-4459.
We previously reported a VEGF autocrine loop in head and neck squamous cell carcinoma (HNSCC) cell lines, supporting a role for VEGF in HNSCC tumorigenesis. Using a phosphotyrosine proteomics approach we screened the HNSCC cell line, SCC-9 for effectors of VEGFR2 signaling. A cluster of proteins involved in cell migration and invasion, including the p130Cas paralog, human enhancer of filamentation1 (HEF1/Cas-L/Nedd9) was identified. HEF1 silencing and overexpression studies revealed a role for VEGF in regulating cell migration, invasion, and MMP expression in a HEF1-dependent manner. Moreover, cells plated on extracellular matrix coated coverslips exhibited enhanced invadopodia formation in response to VEGF that was HEF1-dependent. Immunolocalization revealed that HEF1 colocalized to invadopodia with MT1-MMP. Analysis of HNSCC tissue microarrays for HEF1 immunoreactivity revealed a 6.5-fold increase in the odds of having a metastasis with a high HEF1 score compared to a low HEF1 score. These findings suggest that HEF1 may be prognostic for advanced stage HNSCC. They also demonstrate for the first time, that HEF1 is required for VEGF-mediated HNSCC cell migration and invasion, consistent with HEF1’s recent identification as a metastatic regulator. These results support a strategy targeting VEGF:VEGFR2 in HNSCC therapeutics.
doi:10.1038/onc.2010.185
PMCID: PMC2921319  PMID: 20498643
VEGF; Invadopodia; Cell migration; invasion; HEF1; NEDD9; CAS-L; tyrosine phosphorylation
11.  Robust and Expanded Norms for the Dementia Rating Scale 
The Dementia Rating Scale (DRS) is a widely used measure of global cognition, with age- and education-corrected norms derived from a cross-sectional sample of adults participating in Mayo's Older Americans Normative Studies (MOANS). In recent years, however, studies have indicated that cross-sectional normative samples of older adults represent an admixture of individuals who are indeed cognitively normal (i.e., disease-free) and individuals with incipient neurodegenerative disease. Theoretically, the “contamination” of cross-sectional normative samples with cases of preclinical dementia can lead to underestimation of the test mean and overestimation of the variance, thus reducing the clinical utility of the norms. Robust norming, in which dementia cases are removed from the normative cohort through longitudinal follow-up, is an alternative approach to norm development. The current study presents a reappraisal of the original MOANS DRS norms, provides robust and expanded norms based on a sample of 894 adults age 55 and over, and critically evaluates the benefits of robust norming.
doi:10.1093/arclin/acq030
PMCID: PMC2904669  PMID: 20427376
Dementia Rating Scale; DRS; Alzheimer's disease; Robust; Norms
12.  Mechanism of Binding of Prothioconazole to Mycosphaerella graminicola CYP51 Differs from That of Other Azole Antifungals ▿  
Prothioconazole is one of the most important commercially available demethylase inhibitors (DMIs) used to treat Mycosphaerella graminicola infection of wheat, but specific information regarding its mode of action is not available in the scientific literature. Treatment of wild-type M. graminicola (strain IPO323) with 5 μg of epoxiconazole, tebuconazole, triadimenol, or prothioconazole ml−1 resulted in inhibition of M. graminicola CYP51 (MgCYP51), as evidenced by the accumulation of 14α-methylated sterol substrates (lanosterol and eburicol) and the depletion of ergosterol in azole-treated cells. Successful expression of MgCYP51 in Escherichia coli enabled us to conduct spectrophotometric assays using purified 62-kDa MgCYP51 protein. Antifungal-binding studies revealed that epoxiconazole, tebuconazole, and triadimenol all bound tightly to MgCYP51, producing strong type II difference spectra (peak at 423 to 429 nm and trough at 406 to 409 nm) indicative of the formation of classical low-spin sixth-ligand complexes. Interaction of prothioconazole with MgCYP51 exhibited a novel spectrum with a peak and trough observed at 410 nm and 428 nm, respectively, indicating a different mechanism of inhibition. Prothioconazole bound to MgCYP51 with 840-fold less affinity than epoxiconazole and, unlike epoxiconazole, tebuconazole, and triadimenol, which are noncompetitive inhibitors, prothioconazole was found to be a competitive inhibitor of substrate binding. This represents the first study to validate the effect of prothioconazole on the sterol composition of M. graminicola and the first on the successful heterologous expression of active MgCYP51 protein. The binding affinity studies documented here provide novel insights into the interaction of MgCYP51 with DMIs, especially for the new triazolinethione derivative prothioconazole.
doi:10.1128/AEM.01332-10
PMCID: PMC3067226  PMID: 21169436
13.  Molecular Modelling of the Emergence of Azole Resistance in Mycosphaerella graminicola 
PLoS ONE  2011;6(6):e20973.
A structural rationale for recent emergence of azole (imidazole and triazole) resistance associated with CYP51 mutations in the wheat pathogen Mycosphaerella graminicola is presented, attained by homology modelling of the wild type protein and 13 variant proteins. The novel molecular models of M. graminicola CYP51 are based on multiple homologues, individually identified for each variant, rather than using a single structural scaffold, providing a robust structure-function rationale for the binding of azoles, including important fungal specific regions for which no structural information is available. The wild type binding pocket reveals specific residues in close proximity to the bound azole molecules that are subject to alteration in the variants. This implicates azole ligands as important agents exerting selection on specific regions bordering the pocket, that become the focus of genetic mutation events, leading to reduced sensitivity to that group of related compounds. Collectively, the models account for several observed functional effects of specific alterations, including loss of triadimenol sensitivity in the Y137F variant, lower sensitivity to tebuconazole of I381V variants and increased resistance to prochloraz of V136A variants. Deletion of Y459 and G460, which brings about removal of that entire section of beta turn from the vicinity of the binding pocket, confers resistance to tebuconazole and epoxiconazole, but sensitivity to prochloraz in variants carrying a combination of A379G I381V ΔY459/G460. Measurements of binding pocket volume proved useful in assessment of scope for general resistance to azoles by virtue of their accommodation without bonding interaction, particularly when combined with analysis of change in positions of key amino acids. It is possible to predict the likely binding orientation of an azole molecule in any of the variant CYPs, providing potential for an in silico screening system and reliable predictive approach to assess the probability of particular variants exhibiting resistance to particular azole fungicides.
doi:10.1371/journal.pone.0020973
PMCID: PMC3124474  PMID: 21738598
14.  Mild cognitive impairment associated with limbic and neocortical lewy body disease: a clinicopathological study 
Brain  2009;133(2):540-556.
There are little data on the relationship between Lewy body disease and mild cognitive impairment syndromes. The Mayo Clinic aging and dementia databases in Rochester, Minnesota, and Jacksonville, Florida were queried for cases who were diagnosed with mild cognitive impairment between 1 January 1996 and 30 April 2008, were prospectively followed and were subsequently found to have autopsy-proven Lewy body disease. The presence of rapid eye movement sleep behaviour disorder was specifically assessed. Mild cognitive impairment subtypes were determined by clinical impression and neuropsychological profiles, based on prospective operational criteria. The diagnosis of clinically probable dementia with Lewy bodies was based on the 2005 McKeith criteria. Hippocampal volumes, rate of hippocampal atrophy, and proton magnetic resonance spectroscopy were assessed on available magnetic resonance imaging and spectroscopy scans. Eight subjects were identified; six were male. Seven developed dementia with Lewy bodies prior to death; one died characterized as mild cognitive impairment. The number of cases and median age of onset (range) for specific features were: seven with rapid eye movement sleep behaviour disorder—60 years (27–91 years), eight with cognitive symptoms—69 years (62–89 years), eight with mild cognitive impairment—70.5 years (66–91 years), eight with parkinsonism symptoms—71 years (66–92 years), six with visual hallucinations—72 years (64–90 years), seven with dementia—75 years (67–92 years), six with fluctuations in cognition and/or arousal—76 years (68–92 years) and eight dead—76 years (71–94 years). Rapid eye movement sleep behaviour disorder preceded cognitive symptom onset in six cases by a median of 10 years (2–47 years) and mild cognitive impairment diagnosis by a median of 12 years (3–48 years). The mild cognitive impairment subtypes represented include: two with single domain non-amnestic mild cognitive impairment, three with multi-domain non-amnestic mild cognitive impairment, and three with multi-domain amnestic mild cognitive impairment. The cognitive domains most frequently affected were attention and executive functioning, and visuospatial functioning. Hippocampal volumes and the rate of hippocampal atrophy were, on average, within the normal range in the three cases who underwent magnetic resonance imaging, and the choline/creatine ratio was elevated in the two cases who underwent proton magnetic resonance spectroscopy when they were diagnosed as mild cognitive impairment. On autopsy, six had neocortical-predominant Lewy body disease and two had limbic-predominant Lewy body disease; only one had coexisting high-likelihood Alzheimer's disease. These findings indicate that among Lewy body disease cases that pass through a mild cognitive impairment stage, any cognitive pattern or mild cognitive subtype is possible, with the attention/executive and visuospatial domains most frequently impaired. Hippocampal volume and proton magnetic resonance spectroscopy data were consistent with recent data in dementia with Lewy bodies. All cases with rapid eye movement sleep behaviour disorder and mild cognitive impairment were eventually shown to have autopsy-proven Lewy body disease, indicating that rapid eye movement sleep behaviour disorder plus mild cognitive impairment probably reflects brainstem and cerebral Lewy body disease.
doi:10.1093/brain/awp280
PMCID: PMC2822633  PMID: 19889717
mild cognitive impairment; dementia; dementia with Lewy bodies; Lewy body disease; neuropathology
15.  Internal Consistency and Test-Retest Stability of the Geriatric Depression Scale-Short Form in African American Older Adults 
The Geriatric Depression Scale (GDS) is one of the most widely used self-rated mood questionnaires for older adults. It is highly correlated with clinical diagnoses of depression and has demonstrated validity across different patient populations. However, the reliability of the GDS among African American older adults remains to be firmly established. In a baseline sample of 401 African American adults age 51 and over, the GDS-15 item short form demonstrates good internal consistency (KR20=.71). Stability over a 15-month interval in a retest sample of 51 adults is deemed adequate (r=.68). These findings support the use of the GDS-15 item short form as a reliable mood questionnaire among African American older adults.
doi:10.1007/s10862-008-9123-z
PMCID: PMC2794552  PMID: 20161488
Geriatric depression scale; GDS; Depression; African American; Reliability
16.  Verbal Learning and Memory in Patients with Dementia with Lewy Bodies or Parkinson's Disease with Dementia 
This study compared verbal learning and memory in patients with autopsy-confirmed dementia with Lewy Bodies (DLB) and patients with Parkinson's disease with dementia (PDD). Twenty-four DLB patients, 24 PDD patients, and 24 normal comparison participants were administered the California Verbal Learning Test. The three groups were matched on demographic variables and the two patient groups were matched on the Mattis Dementia Rating Scale. The results indicated that DLB patients recalled less information than PDD patients on all but one recall measure and displayed a more rapid rate of forgetting. In contrast, the PDD patients committed a greater percent of perseveration errors than the DLB patients. The two groups did not differ in the percentage of recall intrusion errors or any measures of recognition. A discriminant function analysis (DFA) using short delay cued recall, percent perseveration errors, and list b recall, differentiated the DLB and PDD groups with 81.3% accuracy. The application of the DFA algorithm to another sample of 42 PDD patients resulted in a 78.6% correct classification rate. The results suggest that, despite equivalent levels of general cognitive impairment, patients with DLB or PDD exhibit a different pattern of verbal learning and memory deficits.
doi:10.1080/13803390802572401
PMCID: PMC2935683  PMID: 19221922
17.  Differential Item Functioning of the Boston Naming Test in Cognitively Normal African American and Caucasian Older Adults 
Scores on the Boston Naming Test (BNT) are frequently lower for African American when compared to Caucasian adults. Although demographically-based norms can mitigate the impact of this discrepancy on the likelihood of erroneous diagnostic impressions, a growing consensus suggests that group norms do not sufficiently address or advance our understanding of the underlying psychometric and sociocultural factors that lead to between-group score discrepancies. Using item response theory and methods to detect differential item functioning (DIF), the current investigation moves beyond comparisons of the summed total score to examine whether the conditional probability of responding correctly to individual BNT items differs between African American and Caucasian adults. Participants included 670 adults age 52 and older who took part in Mayo's Older Americans and Older African Americans Normative Studies. Under a 2-parameter logistic IRT framework and after correction for the false discovery rate, 12 items where shown to demonstrate DIF. Six of these 12 items (“dominoes,” “escalator,” “muzzle,” “latch,” “tripod,” and “palette”) were also identified in additional analyses using hierarchical logistic regression models and represent the strongest evidence for race/ethnicity-based DIF. These findings afford a finer characterization of the psychometric properties of the BNT and expand our understanding of between-group performance.
doi:10.1017/S1355617709990361
PMCID: PMC2835360  PMID: 19570311
Boston Naming Test; Item response theory; Differential item functioning; Ethnicity; Race; Bias
18.  Detecting Dementia with the Mini-Mental State Examination (MMSE) in Highly Educated Individuals 
Archives of neurology  2008;65(7):963-967.
Objectives
To evaluate the utility of Mini-Mental State Examination (MMSE) scores in detecting cognitive dysfunction in a sample of highly educated individuals.
Design
Archival data were reviewed on 4248 participants enrolled in the Mayo Clinic Alzheimer's Disease Research Center (ADRC) and Alzheimer's Disease Patient Registry (ADPR).
Patients
1141 primarily Caucasian (93%) individuals with 16 or more years of self-reported education were identified. These included 307 (164 males and 143 females) dementia cases (any type), 176 patients with Mild Cognitive Impairment (106 males and 70 females), and 658 nondemented controls (242 males and 416 females).
Setting
Mayo Clinic ADRC and ADPR cohort.
Main Outcome Measures
Diagnostic accuracy estimates (sensitivity, specificity, positive and negative predictive power) of MMSE cut-scores in detecting cognitive dysfunction.
Results
In this sample of highly educated, largely Caucasian older adults, the standard MMSE cut-score of 24 (23 or below) yielded a sensitivity of .66, specificity of .99 and an overall correct classification rate of 89% in detecting dementia. A cut score to 27 (26 or below) resulted in an optimal balance of sensitivity and specificity (.89 and .91, respectively) with an overall correct classification rate of 90%. In a cognitively impaired group (dementia and MCI), a cut-score of 27 (sensitivity = .69, specificity = .91) or 28 (sensitivity and specificity = .78) might be more appropriate.
Conclusion
Elderly patients with college education who present with complaints of cognitive decline (self- or other-report) and score below 27 on the MMSE are at greater risk of being diagnosed with dementia and should be referred for a comprehensive dementia evaluation, including formal neuropsychological testing.
doi:10.1001/archneur.65.7.963
PMCID: PMC2587038  PMID: 18625866
Alzheimer's disease; dementia; Mini-Mental State Examination; diagnosis
19.  Structural details and composition of Trichomonas vaginalis lipophosphoglycan in relevance to the epithelial immune function 
Glycoconjugate journal  2008;26(1):3-17.
Trichomonas vaginalis causes the most common non-viral sexually transmitted infection linked to increased risk of premature birth, cervical cancer and HIV. This study defines molecular domains of the parasite surface glycol-conjugate lipophosphoglycan (LPG) with distinct functions in the host immunoinflammatory response. The ceramide phospho-inositol glycan core (CPI-GC) released by mild acid had Mr of ~8,700 Da determined by MALDI-TOF MS. Rha, GlcN, Gal and Xyl and small amounts of GalN and Glc were found in CPI-GC. N-acetyllactosamine repeats were identified by endo-β-galactosidase treatment followed by MALDI-MS and MS/MS and capLC/ESI-MS/MS analyses. Mild acid hydrolysis led to products rich in internal deoxyhexose residues. The CPI-GC induced chemokine production, NF-κB and extracellular signal-regulated kinase (ERK)1/2 activation in human cervicovaginal epithelial cells, but neither the released saccharide components nor the lipid-devoid LPG showed these activities. These results suggest a dominant role for CPI-GC in the pathogenic epithelial response to trichomoniasis.
doi:10.1007/s10719-008-9157-1
PMCID: PMC2637367  PMID: 18604640
Trichomonad LPG; Mass spectrometry; Cytokines; NF-κB; ERK; Vaginal mucosal immunity
20.  Trichomonas vaginalis Lipophosphoglycan Triggers a Selective Upregulation of Cytokines by Human Female Reproductive Tract Epithelial Cells  
Infection and Immunity  2006;74(10):5773-5779.
Trichomonas vaginalis is one of the most common nonviral sexually transmitted human infections and, worldwide, has been linked to increased incidence of human immunodeficiency virus type 1 transmission, preterm delivery, low birth weight, cervical cancer, and vaginitis. The molecular pathways that are important in initiating host inflammatory and immune responses to T. vaginalis are poorly understood. Here we report interactions of human cervicovaginal epithelial cells with the most abundant cell surface glycoconjugate of the parasite, the T. vaginalis lipophosphoglycan (LPG). Purified LPG mediated the adhesion of parasites to human vaginal epithelial cells in a dose-dependent manner. Furthermore, T. vaginalis LPG (but not LPG from Tritrichomonas foetus, the causative agent of bovine trichomoniasis) induced a selective upregulation of chemotactic cytokines by human endocervical, ectocervical, and vaginal epithelial cells, which do not express Toll-like receptor 4/MD2. The T. vaginalis LPG triggered interleukin 8 (IL-8), which promotes the adhesion and transmigration of neutrophils across the endothelium, and macrophage inflammatory protein 3α, which is a chemoattractant for immune cells and is essential for dendritic cell maturation. These effects were dose dependent and sustained in the absence of cytotoxicity and IL-1β release and utilized, at least in part, a signaling pathway independent from the Toll-like/IL-1 receptor adaptor protein MyD88.
doi:10.1128/IAI.00631-06
PMCID: PMC1594934  PMID: 16988255
21.  Genetic Control of Resistance to the Sterol 14α-Demethylase Inhibitor Fungicide Prochloraz in the Cereal Eyespot Pathogen Tapesia yallundae 
Applied and Environmental Microbiology  2000;66(11):4599-4604.
Sexual crosses were used to determine the genetic basis of resistance to the sterol 14 α-demethylase inhibitor fungicide prochloraz in the cereal eyespot pathogen Tapesia yallundae. Three different crosses between sensitive parental strains (22-432 and 22-433 [the concentration required to inhibit growth by 50% {IG50} for each was ≤0.03 mg/liter]) and field isolates from France and New Zealand with differing levels of resistance (PR11 [IG50 = 0.5 mg/liter], PR1 [IG50 = 1.0 mg/liter], and 11-3-18 [IG50 = 2.4 mg/liter]) yielded progeny showing a bimodal distribution, with an even number of sensitive and resistant progeny. This indicated the segregation of a single major gene for resistance in each cross, which was confirmed by the use of backcrosses, crosses between F1 progeny, and control crosses between sensitive parents. However, there was also evidence of additional quantitative genetic components responsible for the increased IG50s of the more resistant isolates. A further cross was made between isolate PR11 and an F1 progeny arising from isolate 11-3-18, and this also yielded progeny which were entirely prochloraz resistant. This suggested that resistance genes were allelic in these two isolates, with resistance conferred by a gene at the same locus (or closely linked loci), despite the fact that the isolates (PR11 and 11-3-18) originated from different continents.
PMCID: PMC92355  PMID: 11055899
22.  Cytomegalovirus Infection in Children Undergoing Open-Heart Surgery 1 
A group of 124 children undergoing open-heart surgery was followed prospectively in order to estimate the risk of cytomegalovirus (CMV) infection due to transfused blood.
Ninety-three patients (75%) had complement fixation (CF) titers of < 1:4 against CMV on admission. Of this seronegative subgroup, nine patients (9.7%) subsequently became infected with CMV. All nine showed seroconversion, and six were viruric 12-14 weeks after surgery. Comparative seroepidemiological studies of the hospital population showed that in the age ranges studied (3-16 yr), the infections seen in the study group represented a significant excess over expectation. This infection rate was consistent with a model of transmission by blood transfusion with a risk of 2.7% per unit but not proven.
Thirty-one patients had CF antibody to CMV on admission. CMV was isolated from 14% of urines of seropositive children both before and after surgery, but only two patients showed CF antibody rises to CMV. Thus the frequency of CMV infection associated with open-heart surgery and transfusion could not be calculated in the seropositive subgroup.
CMV infection was not related to the primary diagnosis or to Down's syndrome.
PMCID: PMC2595348  PMID: 183389
23.  Case of Aneurism of the Abdominal Aorta 
British Medical Journal  1876;2(827):585-586.
PMCID: PMC2298223  PMID: 20748346

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