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C Jenner

Publications and source records attributed to C Jenner.

15 recordsLinked to original sources
PubMed2006

[The clinical syndrome of posterior cortical atrophy].

Posterior cortical atrophy (PCA) is a syndrome that involves distinct neuropsychological deficits. This paper presents the clinical and neuropsychological findings recorded in four patients with PCA and reviews the characteristics of the syndrome and other conditions that need to be considered in the differential diagnosis. The cardinal symptoms of PCA are deficits of higher visual and spatial functions (mostly taking the form of Balint's syndrome), variably associated with disorders of visual perception, topographical disorientation, visual object agnosia and prosopagnosia, and deficits affecting reading, copying, drawing, and calculation. PCA is mostly associated with histopathological changes similar to those found in dementia of Alzheimer type (DAT), which are located predominantly in posterior brain regions. Memory and language functions tend to be preserved better and for a longer time in PCA than in the normal variant of DAT. SPECT and PET show deficits of perfusion and metabolism in both parietal and occipital lobes. The diagnosis of PCA is based on neuropsychological and imaging findings.

Cerebral Cortex↗
PubMed2006

Can cognitive and behavioural disorders differentiate frontal variant-frontotemporal dementia from Alzheimer's disease at early stages?

Frontal variant-Frontotemporal dementia (fvFTD) and Alzheimer's disease (AD) patients matched for severity of dementia at the Clinical Dementia Rating (CDR) received neuropsychological testing in order to explore if the dysexecutive disorder might characterise fvFTD at early stage, when AD is dominated by the episodic memory defect. We also determined if the behavioural syndrome was more severe in fvFTD than AD, and if specific patterns of behavioural symptoms could differentiate the two types of dementia, using the Neuropsychiatry Inventory (NPI). AD patients performed worse than fvFTD not only in memory but also in executive tasks. Apathy and eating disorders proved to be more severe or frequent in fvFTD even if the two groups did not differ in the total NPI score. CDR score significantly correlated with the NPI score in fvFTD and with the MMSE in AD. Our data confirm that the memory disorders may differentiate the two types of dementia; however, the dysexecutive syndrome is as severe, and even more severe in AD. The severity of the behavioural syndrome is comparable in the two groups but the nature of the behavioural disorders may vary to some extent. We conclude that AD dementia at early stage is a behavioural-cognitive syndrome, while in fvFTD the behavioural disorders appear when the cognitive deficit is still relatively mild.

Aged↗
PubMed2004

Behavior in degenerative dementias: mood disorders, psychotic symptoms and predictive value of neuropsychological deficits.

We studied mood disorders (MD) and psychotic symptoms (PS) in patients with fronto -temporal dementia (FTD) and Alzheimer's disease (AD) by means of different diagnostic instruments. These were: a subjective scale (subsets of survey psychiatric assessment schedule: SPAS), an objective scale (subsets of neuropsychiatric inventory: NPI) and a projective task (Wartegg completion task: WCT). A general tendency of NPI to over estimate the presence of symptoms compared to SPAS was observed, but distribution and severity of symptoms were quite homogeneous in the two dementia-groups, independently of the diagnostic scales. At variance with the scales, the WCT showed a more severe impairment in FTD than in AD. The regression analysis selected neuropsychological models able to predict behavioral disorders only in FTD, in particular, a planning deficit predicted PS. These data confirm the hypothesis that a damage in the frontal areas constitutes the neurobiological basis of PS in degenerative brain diseases. Furthermore, they suggest that mostly in FTD, behavioral disorders, as well as cognitive deficits, should be considered a direct expression of neural damage.

Aged↗
PubMed2002

When writing 0 (zero) is easier than writing O (o): a neuropsychological case study of agraphia.

Though a few case studies reported a dissociation between intact writing of Arabic and impaired writing of alphabetical script, a detailed experimental analysis of such a dissociation is still lacking. We report a follow-up study of a patient with a parieto-occipital lesion who is affected by severe peripheral agraphia for letters, but not for Arabic digits. While letters in writing to dictation are frequently illegible, distorted, or consist in meaningless strokes, Arabic digits are well-formed and fluently produced. In a series of tasks, including copying of letters with tachistoscopic presentation and handwriting on a digitizing tablet, several processing levels are assessed in order to localize JS' functional writing impairment and to determine different processing routes for letters and for numbers. Overall, the results of the experimental investigation suggest a notation specific deficit in the activation of graphomotor patterns for letters, but not for digits. The study thus adds evidence to the so far reported dissociations between Arabic and alphabetical scripts.

Aged↗
PubMed1999

Long-term outcomes after function-sparing surgery without radiotherapy for soft tissue sarcoma of the extremities and trunk.

PURPOSE: To define the rate of local recurrence (LR) and identify prognostic factors for LR for patients with soft tissue sarcoma (STS) treated with function-sparing surgery (FSS) without radiotherapy (RT). PATIENTS AND METHODS: Between 1970 and 1994, 242 patients with STS of the trunk and extremity presented with primary localized disease, 74 of whom were treated with FSS without RT (31%). The median tumor size was 4 cm (range, 0.5 to 31 cm). There were 40 patients with grade 1 tumors and 34 with grade 2 and 3 tumors. Median follow-up was 126 months. RESULTS: The 10-year actuarial local control rate was 93% +/- 4%. Resection margin status was a significant predictor for LR. Patients with closest histologic resection margins of less than 1 cm had a 10-year local control rate of 87% +/- 6% compared with 100% for patients with closest histologic resection margins of >/= 1 cm (P =.04). There was no significant association between LR and tumor grade, size, site (truncal v extremity), or depth (superficial v deep). For all patients, the 10-year actuarial survival rate was 73% +/- 6%. CONCLUSION: The 7% LR rate after treatment of STS with FSS without RT reported herein is comparable to published rates following treatment where adjuvant RT is used. These results suggest there may be a select subset of patients with STS in whom carefully performed FSS may serve as definitive therapy and in whom adjuvant RT may not be necessary. However, further study is needed to carefully define this subset of patients and to identify the optimal surgical approach and technique for patients treated without RT.

Adult↗
PubMed1997

Responses of mature and aged sympathetic neurons to laminin and NGF: an in vitro study.

Whilst the potent effects of NGF and laminin on developing neurons are well documented, relatively little is known about the effects of, or altered availability of or altered responsiveness to, these substances on the growth of adult neurons. We have therefore examined this question using explant cultures of sympathetic neurons from the superior cervical ganglion (SCG) of mature and aged rats. Explants were grown on substrata containing different doses of laminin, either with or without added NGF in culture medium containing FCS. Individually, laminin and NGF had relatively small effects on neurite outgrowth and length, which tended to be reduced in old neurons. In contrast, laminin in the presence of exogenous NGF exerted a powerful effect on nerve growth which was substantially greater than the sum of the effects of the individual factors. This synergy was evident in all experimental groups and was greatest in old explants at high doses of laminin, where growth was comparable to that of mature neurons. The dose-response curve of old neurons to laminin in the presence of added NGF indicated reduced responsiveness. These results suggest that variations in the availability of laminin and/or exogenous NGF, together with altered patterns of neuronal responsiveness, may contribute to impaired neuronal plasticity in old age.

Aging↗
PubMed1997

Expression of avrPphB, an avirulence gene from Pseudomonas syringae pv. phaseolicola, and the delivery of signals causing the hypersensitive reaction in bean.

Protein production encoded by the avirulence gene avrPphB from Pseudomonas syringae pv. phaseolicola was examined. Incorporation of [35S]-labeled methionine into the AvrPphB protein indicated processing of the full-length peptide in Escherichia coli to give a major 28-kDa product. The 28-kDa native peptide was isolated from E. coli following over-expression of avrPphB and found not to elicit the hypersensitive response (HR) after infiltration into bean leaves. Antiserum raised to the 28-kDa peptide allowed expression of avrPphB and processing of AvrPphB protein to be examined in P. syringae pv. phaseolicola; immunoreactive peptides of both 35 and 28-kDa were detected in races 3 and 4 (which contain avrPphB) only after induction in minimal medium + 10 mM sucrose. Antiserum raised to a synthetic peptide, derived from the sequence of the 62 amino acids found to be cleaved from the full-length AvrPphB protein, revealed the accumulation of peptides corresponding to the smaller cleavage products, in both E. coli and P. syringae pv. phaseolicola. Biochemical localization experiments showed that all AvrPphB peptides were cytoplasmic in P. syringae pv. phaseolicola. No AvrPphB peptides were produced in a hrpL mutant unless expression of the gene was directed by a strong vector promoter; induction kinetics similar to wild type were observed in a hrpY- strain, although it also failed to cause a confluent HR. Growth of P. syringae pv. phaseolicola under inducing conditions removed the requirement for rifampicin-sensitive mRNA synthesis by bacteria to allow HR development (the induction time) in bean and lettuce leaves. Constitutive expression of hrpL reduced but did not remove the induction time. Expression of the hrp gene cluster of P. syringae pv. phaseolicola from plasmid pPPY430 in E. coli enabled phenotypic expression of avrPphE (also carried by pPPY430) and avrPphB (if over-expressed from pPPY3031). Despite constitutive expression of the hrp and avr genes in E. coli, a protein synthesis dependent induction time was still required for development of the HR in bean genotypes with matching resistance genes. The significance of processing for the function of AvrPphB peptides and the delivery of elicitors of the HR are discussed.

Amino Acid Sequence↗
PubMedDate not supplied

Characterization of avrPphE, a gene for cultivar-specific avirulence from Pseudomonas syringae pv. phaseolicola which is physically linked to hrpY, a new hrp gene identified in the halo-blight bacterium.

The avirulence gene matching the R2 gene for resistance to halo-blight disease in Phaseolus was cloned and sequenced from race 4 strain 1302A of Pseudomonas syringae pv. phaseolicola. The predicted 41-kDa AvrPphE protein is hydrophilic, has no features that indicate function, and no similarity to other protein sequences. The promoter region of avrPphE contains a "harp box" motif. The gene was expressed more strongly in minimal than in nutrient-rich media. Lower concentrations of the phytoalexin phaseollin accumulated in tissue undergoing the hypersensitive reaction (HR) determined by avrPphE than by avrPphB. Homologs of avrPphE were detected in strains representing eight races of P. s. pv. phaseolicola including those virulent on cultivars with the R2 resistance gene, and in P. s. pv. tabaci but not in P. cichorii or P. s. pvs. coronafaciens, glycinea, maculicola, pisi, or syringae. Disruption of avrPphE prevented induction of the HR but did not appear to affect basic pathogenicity. Transposon mutagenesis and DNA sequencing showed that avrPphE was linked to hrpY a hrp locus identified at the left end of the hrp gene cluster. Sequence analysis showed that the region linked to avrPphE was very similar to DNA containing hrp genes from P. s. pv. syringae including hrpJ, hrpL, and hrpK.

Amino Acid Sequence↗
PubMedDate not supplied

Gene-for-gene interactions between Pseudomonas syringae pv. phaseolicola and Phaseolus.

The gene for cultivar-specific avirulence to Phaseolus vulgaris cv. Tendergreen in races 3 and 4 of Pseudomonas syringae pv. phaseolicola was isolated and sequenced. Genomic clones from libraries of race 3 in pLAFR1 and race 4 in pLAFR3, which altered the phenotype of race 5 from virulent to avirulent in Tendergreen, were found to possess a common approximately 15-kb region of DNA that contained the determinant of avirulence. Subcloning and insertion mutagenesis with Tn1000 located an avirulence gene within a 1.4-kb BglII/HindIII DNA fragment in races 3 and 4. Comparison of the nucleotide sequences of regions of DNA that confer avirulence confirmed that both races have an identical gene for avirulence (designated avrPph3) comprising 801 base pairs (bp) and predicted to encode a cytoplasmic protein of 28,703 Da. A sequence, TGCAACCGAAT, 91% homologous to the motif found in promoter regions of avrB and avrD from P. s. pv. glycinea was located 89-99 bp upstream of the start of the open-reading frame 1. Hybridization experiments showed that avrPph3 was not plasmid-borne and was absent from isolates of P. s. pv. phaseolicola races 1, 2, 5, 6, 7, and 8, P. cichorii, P. s. pvs. coronafaciens, glycinea, maculicola, pisi, syringae, and tabaci. Cosegregation studies of crosses between cultivars resistant (Tendergreen) and susceptible (Canadian Wonder) to races 3 and 4 and transconjugants of race 5 confirmed that a gene-for-gene relationship controls specificity in the interaction between Tendergreen and races 3 and 4 of P. s. pv. phaseolicola.

Amino Acid Sequence↗
PubMedDate not supplied

[Personality-specific disposition to stomach cancer].

24 patients (10 female and 14 male) with a histologically evident stomach cancer underwent a series of psychoanalytical interviews and psychological tests (TAT). The method consisted of an analysis of early childhood conditions, the structure of personality, the object relationships, as well as the psychic causes for the stomach cancer. Among the results was that the loss of one parent or an equivalent early loss was significantly more frequent in stomach cancer patients than in the average population. Their predominant sibling position was the so-called sandwich-position. In regard to the structure of personality a constantly persisting false assimilation of inner conflicts presents itself as the essential item of the premorbid structure. The initiating factor for the stomach cancer was a statistically significantly often experienced severe trauma based on a significantly often experienced object loss, especially during childhood, as well as on a family disposition in the relation of 1:50. In addition to that the following conspicuous features were responsible for the formation of the stomach cancer: A persisting problem of separation (Oedipus conflicts), a resignation in an apathetic reaction (excessive demands), an inability to release aggression in a "normal" way and a direction of the aggression against the person himself.

Adolescent↗