In vitro MR microscopy of the hippocampus in Alzheimer''s disease

In prepubertal children, teratoma is a benign tumor, whereas in adolescents and adults, it behaves as a malignant neoplasm. Adult patients without evidence of metastases may be candidates for surveillance after orchiectomy, and those with low-volume or borderline retroperitoneal metastases thought to contain teratoma might best be managed by surgery, as teratomatous deposits do not respond to chemotherapy. Patients with larger retroperitoneal metastases may be given chemotherapy before surgery to reduce or eliminate other germ-cell elements. Teratomatous masses persisting after chemotherapy are excised by most clinicians, in part to obtain a pathologic diagnosis. In childhood tumors, inguinal orchiectomy or enucleation is sufficient if one is certain the lesion contains only teratoma.     

Biological markers of Alzheimer''s disease

A 49-year-old woman presented with splenic lymphoma with villous lymphocytes (SLVL) that showed a clonal abnormality of del(7)(q22q32) in addition to inv(10)(p13q23), the latter being a previously undescribed abnormality in chronic lymphoproliferative disorders. A review of the literature on cytogenetic abnormalities of SLVL indicates that del(7q) is strongly associated with SLVL and may be important in the pathogenesis of this disorder.     

Neurochemical studies of Alzheimer''s disease

Age differences in the representation of semantic information may underlie the cognitive decline observed in aging. The objective of the present study was to determine to what extent elderly and young subjects agreed in the representations of semantic categories. Ninety elderly (77 women, 13 men) and 90 young (74 women, 16 men) participants wrote down the first four associations evoked by each of 30 semantic category names. Results showed differences between the two groups in items selected as most common responses (MCRs); frequency of occurrence of the MCRs differed between the two groups in 21 semantic categories. Results suggest that young and elderly subjects hold different representations of semantic categories and also highlight the importance of using age-appropriate norms in the evaluation of cognitive functions in aging.     

Differential chromosome sensitivity to 5-azacytidine in Alzheimer''s disease

The chemiluminescence (CL) technique with scavengers for superoxide anion (superoxide dismutase) and hydrogen peroxide (catalase) was used to characterize the generation of reactive oxygen species (ROS) inside and outside the human neutrophil after stimulation with both soluble (formyl-methionyl-leucyl-phenylalanine, FMLP) and particulate (urate crystals, zymosan, oxidized LDL) stimuli. Depending on the stimulus used, ROS generation differed in composition and absolute amounts. The ratio between extracellularly and intracellularly produced ROS ranged from 0.3 (zymosan) to 4.2 (FMLP). While enhancing substantially FMLP-stimulated CL, horseradish peroxidase inhibited CL induced by particulate stimuli by 40-80%. Furthermore, an azide-insensitive and therefore peroxidase-independent part of CL was found in FMLP-, LDL- and zymosan-stimulated cells. The results indicate that different agonists may lead through distinct chemical pathways to neutrophil luminol-amplified light generation.     

自适应分数阶微分在图像纹理增强中的应用

针对目前只能通过人为实验指定最佳分数阶微分阶数的现状,为了节省大量人工寻求最佳分数阶微分阶数的时间,研究并提出了可以依据掩模窗口大小、G-L公式、图像梯度特征和人眼视觉特性等理论的能够自动生成分数阶微分阶数的新方法,基于该自适应阶数,设计并实现了对应的算子掩模.采用了信息熵、平均梯度等图像纹理特征评价参数做定量分析和实验验证,结果表明,该方法对任意灰度图像可以得到连续变化的增强效果,接近于最佳分数阶微分增强效果,符合人们的视觉感受,是有效的图像纹理增强方法.     

Alzheimer''s disease: the advent of effective therapy

PURPOSE: To investigate the astigmatic keratotomy effect of a modified single-hinge cataract incision. SETTING: Department of Ophthalmology, San Juan de Dios Hospital, Tenerife, Spain. METHODS: This prospective study evaluated the astigmatic changes resulting from preincision grooves of less than 40, 45, and 55 degrees in arc length used with a single-hinge, self-sealing cataract incision in 144 eyes that had against-the-rule corneal astigmatism preoperatively. The intended 90% depth preincision was centered on the steep meridian and lengthened according to the amount of preoperative astigmatism. Outcome measurements were obtained by calculating the surgically induced astigmatism vectors and the postoperative keratometry changes 1 day, 1 week, and 1, 3, and 6 months after surgery. RESULTS: Three months postoperatively, astigmatism decreased by 0.03, 0.30, and 0.68 diopter in the less than 40, 45, and 55 degree incision length groups, respectively. The differences between the 45 and 55 degree groups and the less than 40 degree group was statistically significant (P < .05). Similar results were observed 6 months after surgery. CONCLUSION: The astigmatic preincision modification produced statistically significant increasing reductions in preoperative astigmatism according to preincision length.     

Anosognosia and procedural learning in Alzheimer''s disease

Biochemical modulation of 5-fluorouracil (5-FU) by folinic acid (FA) increases the response rate in patients with metastatic colorectal cancer compared to 5-FU alone. Phase II trials also demonstrated increased efficacy when interferon was added to 5-FU. In two consecutive trials, 76 patients were treated on days 1-5 with FA 200 mg/m2 plus interferon 5 x 10(6) U/m2 and 5-FU 350 mg/m2 as intravenous bolus injection (n = 33, regimen A) or 5-FU 500 mg/m2 as 2-hour infusion (n = 43, regimen B), repeated every 3 weeks with individual 5-FU dose escalation in steps of 50 (regimen A) or 100 mg/m2 (regimen B). In regimen A 5-FU dose reduction to 300 mg/m2 due to toxicity was necessary in 49% of the patients; in regimen B a 5-FU dose of 600 mg/m2 or above was tolerated by 70% of the patients. Dose-limiting toxicity was severe mucositis and/or diarrhea. Objective responses were observed in 5 of 33 patients (15%) in regimen A (3-28%, 95% confidence interval) and 7 of 41 patients (17%) in regimen B (5-29%, 95% confidence interval). Median time to progression was 4.7 and 4.8 months, and median survival 9.9 and 11.4 months for regimens A and B, respectively. Prolonged 5-FU administration over 2 h allows the administration of a higher 5-FU dose compared to bolus injection with no apparent improvement in antineoplastic efficacy. The addition of interferon to the combination of 5-FU plus FA in this dose and schedule does not seem to improve the response rate but appears to increase treatment toxicity.     

Use of electroencephalography to detect Alzheimer''s disease in Down''s syndrome

Asthma is one of the most common chronic illnesses in childhood. Increases in hospitalization rates have occurred in several countries. The cumulative risk of asthma requiring medical attention was 11.7% for males and 7.0% for females aged 0-4 in Manitoba, Canada, for the cohort of children born in 1984/1985. The cumulative risk of hospitalization for males was nearly twice that of females (2.1% vs. 1.1%). Disease onset was most likely at age 1 year. The risk of rehospitalization or return physician visit for asthma increased significantly with the number of prior hospitalizations and physician visits, respectively, which may reflect both the persistence of asthma and the difficulty of developing an effective disease management strategy.     

Clinical and genetic analysis of a pedigree of a thirty-six-year-old familial Alzheimer''s disease patient

Distribution of apolipoprotein(apo) E4 and E3 in lipoproteins of serum with apoE4/E3 phenotype was analyzed. ApoE was eluted in two major peaks by gel chromatography; peak 1 and 2 corresponding to very- and intermediate-low density lipoprotein (VLDL + IDL) and high density lipoprotein2 (HDL2), respectively. ApoE in peak 1 (VLDL + IDL) consisted of monomers of 34 kDa, complexes with a high molecular weight (apoEs) of 100 kDa and with a small amount of apoE-AII complexes weighing 43 kDa. In contrast, apoE in peak 2 (HDL2) was composed mainly of apoE-AII complexes and apoEs complexes, and a small amount of monomers. Both apoE3 and E4 isoforms were detected in these peaks; E4 was more predominant in peak 1 while E3 was more predominant in peak 2. These findings suggest that different distributions of apoE3 and E4 in lipoprotein particles.     

Aluminium, neurofibrillary degeneration and Alzheimer''s disease

The calcium-binding protein (parvalbumin), isolated from carp (Cyprinus carpio) muscle, has been specifically fragmented into two polypeptides by tryptic hydrolysis at the single arginine residue at position 75. Fragment A contains residues 1 leads to 75 and fragment B is composed of residues 76 leads to 108. The fragments have been characterized according to size, amino acid composition, carboxyl- and aminoterminal analysis. Both fragments appear to be homogeneous by these criteria. The intact protein is known to bind 2 mol of calcium per mol of parvalbumin, and although each fragment alone contains all of the essential ligands for the coordination of one Ca2+, neither fragment displays calcium binding activity. Attempts to reconstitute the two fragments, under a variety of conditions, into a functional complex which can bind calcium have been unsuccessful. The side chain of Arg-75 is known to occupy an internal position in the crystalline structure of parvalbumin (Kretsinger, R.H. and Nockolds, C.E. (1973) J. Biol. Chem. 248, 3313), where it is stabilized by an intricate network of hydrogen bonding involving the side chain of Glu-81. Although this internal salt bridge is approx. 20 A from either calcium binding site, it has been suggested that this structural feature of the molecule plays an essential role in the reversible binding of Ca2+. That the side chain of Arg-75 likewise occupies an internal position in the solution structure is indicated by its unavailability for reaction with 1,2-cyclohexanedione under conditions of physiological pH and temperature. However, in the presence of EDTA and at pH 8, it is readily modified by cyclohexanedione. This modification is accompanied by a concomitant loss in calcium binding activity. Reversal of the modification by treatment with hydroxylamine is accompanied by restoration of calcium binding activity. The serum of these data support the hypothesis that Arg-75 plays a critical role in the structural organization and calcium binding activity of the molecule, and in addition, suggests that the integrity of the peptide bond between Arg-75 and Ala-76 may be necessary for establishing the proper micro-environment required for formation of the internal salt bridge between Arg-75 and Glu-81.     

Prevalence and correlates of anxiety in Alzheimer''s disease

Short-lived occupational skin symptoms of irritant or urticarial nature were commonly reported among 253 attendants in a clinical study on occupational dermatitis in Danish gardeners and greenhouse workers. Aimed prick or scratch-patch testing for immediate skin and mucosal symptoms was performed in 105 persons with plants as is. 35 persons (33%) had at least 1 positive reaction and a family history of, or personal, atopy was significantly more prevalent among these compared to attendants with negative reactions. Positive histamine release tests made immunologic etiology probable in Schlumbergera cacti, Stephanotis floribunda, Euphorbia pulcherrima and Gerbera reactions. Other new species implicated in immediate-type reactions included Ficus pumila, Gardenia jasminoides, Hibiscus rosa-sinensis, Campanula, Columnea, Epipremnum aureum, Pelargonium and Primula vulgaris. Because of the high prevalence of short-lived skin symptoms and because contact urticaria may present itself as a dermatitis, it is recommended that one supplement patch tests with tests for immediate reactions.     

Automated image analysis applied to the odontoblast-predentine region in undemineralized sections of human permanent third molars

A case of desmoplastic melanoma in a 72-year-old patient is reported. In the light of this case, the authors review the literature and analyse the therapeutic implications.     

Loss of dopamine D2 receptors in Alzheimer''s disease with parkinsonism but not Parkinson''s or Alzheimer''s disease

Qualitative analyses of midfoot stabilization in triple arthrodeses utilizing bone staple versus 4.5-mm cannulated cancellous screw fixation, with and without washers, were performed in fresh cadaveric specimens. Twenty-two trials (11 matched-pair feet) were used for direct comparison. Stiffness, defined as force/displacement, was determined at each talonavicular and calcaneocuboid joint. Ultimate load failure points of each specimen were also calculated. Trial results showed no statistically significant difference in stiffness or ultimate failure between these two forms of midfoot fixation for triple arthrodeses.     

Advances and challenges in the prevention and treatment of Alzheimer''s disease

We used positron emission tomography (PET) to measure movement set-related changes in regional cerebral blood flow (rCBF) when human subjects were asked to copy hand movements. Movement set-related activity in the brain is thought to reflect the processes of movement selection, preparation and inhibition. Four conditions were used. In the first condition, prepare and execute (PE), the hand stimulus to be copied was shown to subjects 3 s before an auditory "go"-cue instructed subjects to execute the movement; a large part of the scanning time was therefore spent in preparing to move. In the immediate execution condition (E), the hand stimulus and the go cue were presented simultaneously. The prepare-only condition (P) was similar to PE, except subjects only prepared to make the movement and did not actually execute any movement when they heard the auditory go-cue. The same stimuli were presented in a baseline condition (B), but the subjects were instructed to neither prepare nor execute movements. There were 5 principle findings: (1) In contrast to a previous study of human set-related activity in which movements were instructed by an arbitrary pattern of LEDs, preparing to make a copied movement causes rCBF changes in area 44 in posterior Broca's area; (2) set-related activity can be recorded in the cerebellar hemispheres and midline; (3) we confirmed that the supramarginal gyrus has a general role in preparing movements - there was more rCBF in the P than the E condition; (4) the cerebellar nuclei and the basal ganglia may be particularly involved in the initiation and execution of a planned movement; these regions were more active in the PE condition than the P condition; (5) the ventrolateral prefrontal cortex and a left anterior cingulate area are part of a distributed system involved in the suppression of a motor response; these areas were significantly more active in the P than the PE condition.     

Early diagnostic indices for the prevention of Alzheimer''s disease

A flow-cytometric (FCM) and fluorescence in situ hybridization (FISH) study was performed in 153 patients with clinically localised prostate cancer (PC) to evaluate retrospectively the prognostic significance of DNA ploidy, S-phase fraction (SPF) and chromosome 7 copy number. Deletions in 7q31.1 were analysed in a subset of 26 tumours. The mean follow-up time was 6 years (range 4-16 years). Twelve cases of benign prostatic hyperplasia (BPH) were studied as a control. Chromosome 7 enumeration and deletion studies were conducted using the alpha-satellite D7Z1 probe and a cosmid probe specific for the marker D7S522 on 7q31.1. Higher SPF was associated with shorter overall survival and shorter time to local progression and metastasis. Near diploid (DNA index 1.05-1.20) cases had a lower frequency of metastases and lower Gleason scores than aneuploid cases. Increased absolute chromosome 7 copy number (centromere count) was associated with higher Gleason score, higher SPF and shorter local progression-free and prostate cancer survival. Absolute chromosome 7 copy number was concordant with FCM DNA ploidy in the majority (75%) of cases. Relative gain or loss of chromosome 7 (centromere counts compared to ploidy) was infrequent, and no correlation was found with clinical parameters. Deletions in 7q31.1 were infrequent. Our results indicate that in localised PC (i) SPF is a prognostic factor, (ii) absolute chromosome 7 copy number is concordant with the ploidy status of the tumour (relative gain or loss of chromosome 7 is infrequent and has no independent prognostic value) and (iii) the frequency of deletions in 7q31.1 is low and not correlated with clinical outcome.     

Determinants of carer stress in Alzheimer''s disease

Ovarian cancer is the fifth most common malignancy among American women and the fourth leading cause of cancer death. The rapid advances in molecular genetic analysis, presymptomatic detection, and treatment of ovarian cancer are staggering. In this review, both the genetic component and the molecular biology of ovarian cancer are discussed, as well as current recommendations for genetic counseling. It is important for the practicing obstetrician and gynecologist to become familiar with these concepts, for it is he or she who will likely serve as a primary resource of information for these patients.     

Controlled and automatic memory process in Alzheimer''s disease

Treatment of cultured rat hepatocytes with cyclosporin A (0.01-1 microM) for 24, 48, or 72 h in the presence of insulin and epidermal growth factor induced an inhibition on cell proliferation in a time- and concentration-dependent manner, with an IC50 = 0.05 microM CsA corresponding to 48-h treatment. The inhibitory effect of CsA at < or = 0.1 microM doses for 48 h on [3H]thymidine uptake was reversed after withdrawal of the drug and subsequent addition of insulin plus EGF or serum; however, at 1 microM CsA the effect was irreversible and numerous bright small vesicles were observed. The molecular mechanism involved in CsA action in hepatocytes seems to be independent on cAMP and pertussis-toxin sensitive G proteins.     

Frontal lobe hypometabolism and depression in Alzheimer''s disease

PURPOSE: It is speculated that the susceptibility to urothelial cancer in dye workers who are exposed to aromatic amines is affected not only by occupational environmental factors but by host specific factors. We evaluated the interaction between glutathione S-transferase M1 gene deficiency and the occupational environmental factors associated with urothelial cancer. MATERIALS AND METHODS: The study included 137 workers who had prior exposure to dyestuff intermediates, of whom 36 had urothelial cancer. The prevalence of a glutathione S-transferase M1 gene polymorphism was investigated using polymerase chain reaction. The relationship between the glutathione S-transferase M1 0/0 gene and occupational environmental factors in the onset of urothelial cancer was examined by multivariate analysis. RESULTS: The prevalence of glutathione S-transferase M1 gene deficiency did not differ significantly between the urothelial cancer (21 cases, 58.3%) group and the cancer-free (47, 46.3%) group. It was estimated that 29.6% of the urothelial cancers in these dye workers was attributable to the glutathione S-transferase M1 0/0 gene. Analysis using multiple logistic models showed low predictive ability for urothelial cancer due to glutathione S-transferase M1 gene deficiency (p = 0.084, odds ratio 2.260, 95% confidence interval [CI] 0.904 to 5.652). A history of working in small factories (p = 0.000, odds ratio 7.404, 95% CI 2.854 to 19.206) and a long period of exposure (p = 0.016, odds ratio 5.051, 95% CI 1.371 to 18.612) significantly predicted cancer. CONCLUSIONS: We demonstrated a strong trend using the multiple logistic analysis of the contribution of glutathione S-transferase M1 gene polymorphism and occupational environmental factors. Therefore, the glutathione S-transferase M1 enzyme might have an important role in the detoxification of aromatic amine derived carcinogens. Occupational environmental factors, however, might contribute more than a glutathione S-transferase M1 gene deficiency to the occurrence of urothelial cancer among individuals exposed to aromatic amines, because of the extremely potent carcinogenicity of some occupational environmental factors.     

The spherical image concept applied to grain structures

The spherical image of the boundary of a microstructural feature is a map of the directions of its surface normals on the unit sphere of orientation. For closed surfaces it is a topological invariant. For curved faced polyhedra, as are found in grain structures or other tessellations of three dimensional space, the corners, edges and faces all contribute to the spherical image. The geometries of the spherical images of corners, edges and faces are described in this paper. These geometric concepts are applied to individual cells, the cell set, and the triple lines and quadruple points in the corresponding tessellation. Equations are derived relating the contributions of these spherical images to the number of faces on a single cell and to the average number of faces per grain for the structure. Application of these relations to grain structures governed by local capillarity equilibrium demonstrate that it is unlikely that the average number of faces per grain will deviate significantly from 13.4.