ß-Amyloid burden in healthy aging: regional distribution and cognitive consequences.

OBJECTIVE: Several lines of evidence suggest that pathologic changes underlying Alzheimer disease (AD) begin years prior to the clinical expression of the disease, underscoring the need for studies of cognitively healthy adults to capture these early changes. The overall goal of the current study was to map the cortical distribution of ß-amyloid (Aß) in a healthy adult lifespan sample (aged 30-89), and to assess the relationship between elevated amyloid and cognitive performance across multiple domains. METHODS: A total of 137 well-screened and cognitively normal adults underwent Aß PET imaging with radiotracer (18)F-florbetapir. Aß load was estimated from 8 cortical regions. Participants were genotyped for APOE and tested for processing speed, working memory, fluid reasoning, episodic memory, and verbal ability. RESULTS: Aß deposition is distributed differentially across the cortex and progresses at varying rates with age across cortical brain regions. A subset of cognitively normal adults aged 60 and over show markedly elevated deposition, and also had a higher rate of APOE ε4 (38%) than nonelevated adults (19%). Aß burden was linked to poorer cognitive performance on measures of processing speed, working memory, and reasoning. CONCLUSIONS: Even in a highly selected lifespan sample of adults, Aß deposition is apparent in some adults and is influenced by APOE status. Greater amyloid burden was related to deleterious effects on cognition, suggesting that subtle cognitive changes accrue as amyloid progresses.

Effect of dry honey on the shelf life of packaged turkey slices.

The development of off-flavors from oxidation reactions in cooked turkey products is a common problem and results in a less desirable, rancid flavor. Various strategies have been evaluated to minimize this off-flavor development, including vacuum and modified atmosphere packaging, feeding antioxidants to animals, and use of antioxidants in the final product. A natural protein-sugar reaction called the Maillard reaction produces a brown pigment, flavors, and antioxidants. This research tested the addition of honey to turkey breast meat before processing to retard production of oxidation products related to off-flavor. Three levels (0, 5, 15%) of dry honey were mixed with raw turkey breast meat pieces, then the mixture was stuffed into casing and cooked. The cooking process facilitated the Maillard reaction and the development of an antioxidative effect. The cooked chubs were then cooled, sliced, and vacuum-packaged as individual slices. The slices were refrigerated and tested for color, flavor, oxidative rancidity, and microbial growth over 11 wk. Sensory panelists detected increased sweetness and no negative flavor impact on acceptability for turkey with added honey. The addition of honey enhanced the oxidative stability of the meat, as indicated by lower TBA values, hexanal content, and oxidative stability index. Honey did impart a slightly darker color with lower lightness values but had no effect of redness and yellowness values.

Thickness and compositional effects on surface heating rate of bologna during in-package pasteurization.

The surface heating rate (gamma) and final surface temperature (alpha) during in-package pasteurization were determined for different thickness levels of 2 types of bologna having different (13 and 18%) fat contents. Three thicknesses (4, 12, and 20 mm), corresponding to 1, 3, and 5 slices of bologna, were vacuum-packaged separately in a clear polymer pouch after placing a thermocouple on the surface. Refrigerated samples were immersed in a water bath set to 1 of 4 predetermined temperatures (60, 70, 80, and 90 degrees C), and time and temperature data were recorded for 10 min. Surface heating rate was fastest in the thinnest (4 mm) and slowest in the thickest (20 mm) samples for all 4 temperatures. Surface heating rate was slower in bologna with the higher fat content compared with the lower fat bologna. Final surface temperature attained after 3 min was lower with increased thickness levels for all temperatures. Thus, meat sample thickness and fat content significantly affect surface heating rate and final surface temperature during in-package pasteurization of bologna.

Antioxidative effect of maillard reaction products formed from honey at different reaction times.

Maillard reaction products (MRP) were synthesized from honey-lysine by refluxing with water for 4, 8, 12, 16, and 20 h. The MRP from each reaction time were added to and reacted with a linoleic acid buffered emulsion at 37 degrees C. The MRP from each of the five reaction times were added to the linoleic acid emulsion (LAE) at 1%, 5%, 10%, 15%, and 20% (v/v). The antioxidative effect of MRP on the LAE was determined spectrophotometrically at 234 nm. The MRP pH and brown pigment formation (450 nm) was measured. Absorbance at 450 nm increased from 0.6 to 1.6 between the 4 h and 20 h MRP treatments, respectively. The pH of the MRP decreased from 4 h to 20 h reaction solutions, ranging from 4.2 to 3.65. The antioxidative effect increased at each reaction time increment. Within each reaction time, the antioxidative effect was maximized between 10% and 15% addition levels.

Effect of dry honey on oxidation in turkey breast meat.

The effect of adding dry honey to turkey breast meat on oxidative stability was measured using TBA, volatile headspace, and oxidative stability index. Ground turkey breast meat was mixed with different concentrations of dry honey (0, 1, 5, 10, 15, and 20%) then cooked in polyethylene bags to 72 C. Oxidative stability measurements were taken for raw meat and cooked meat and for cooked meat after 48 h of storage at 4 C. The proximate composition of the raw meat was 73.9% moisture, 23.2% protein, and 1.3% fat. Gas headspace analysis determined hexanal to be the most abundant volatile compound. Hexanal content decreased as the amount of added honey increased in both freshly cooked meat and in meat stored for 48 h at 4 C. The TBA values also decreased with increasing levels of added honey in the freshly cooked and 48-h-stored meats. The percentage inhibition of oxidation for the 5, 10, 15, and 20% samples increased from 50 to 76% for the freshly cooked meat and from 34 to 88% for the 48-h-stored meat. The oxidative stability index increased with increasing concentrations of honey from 0.28 h (control) to 7.73 h (20% honey). Addition of up to 15% honey inhibited the development of oxidative compounds in cooked turkey meat, with little further inhibition observed compared to 20% honey.

Urinary loss of thiamine is increased by low doses of furosemide in healthy volunteers.

Prolonged furosemide treatment is associated with urinary loss of thiamine and thiamine deficiency in some patients with congestive heart failure and low dietary thiamine intake. In the rat, diuretic-induced thiamine urinary loss is solely dependent on increased diuresis and is unrelated to the type of diuretic used. We studied the effects of single intravenous doses of furosemide (1, 3, and 10 mg) and of normal saline infusion (750 mL) on urinary thiamine excretion in 6 volunteers. Over a 6-hour period, furosemide induced dose-dependent increases in urine flow and sodium excretion rates (mean +/- SD), from 51 +/- 17 mL/h at baseline to 89 +/- 29 mL/h, 110 +/- 38 mL/h, and 183 +/- 58 mL/h (F = 10.4, P < .002) and from 5.1 +/- 2.3 mmol/h to 9.4 +/- 6.8 mmol/h, 12.1 +/- 2.6 mmol/h, and 20.9 +/- 10.6 mmol/h (F = 6.3, P < .005) for the three doses, respectively (104 +/- 35 mL/h and 13.0 +/- 6.2 mmol/h for the saline infusion). During this period the thiamine excretion rate doubled from baseline levels (mean of four 24-hour periods before the diuretic interventions) of 6.4 +/- 5.1 nmol/h to 11.6 +/- 8.2 nmol/h (F = 5.03, P < .01, for all four interventions, no difference being found between them), then returning over the following 18 hours to 6.1 +/- 3.9 nmol/h. The thiamine excretion rate was correlated with the urine flow rate (r = 0.54, P < .001), with no further effect of the type of intervention or sodium excretion rate. These findings complement our previous results in animals and indicate that sustained diuresis of >100 mL/h induces a nonspecific but significant increase in urinary loss of thiamine in human subjects. Thiamine supplements should be considered in patients undergoing sustained diuresis, when dietary deficiency may be present.

[Cytogenetic changes in low grade central osteosarcomas]. / Zytogenetische Veränderungen bei niedrigmalignen zentralen Osteosarkomen.

Low grade central osteosarcomas are a group of rare bone neoplasms morphologically simulating benign bone tumors or tumor-like lesions (fibrous dysplasia, nonossifying fibroma, osteoblastoma, chondromyxoidfibroma or aneurysmal bone cyst). Because of the apparent bland histology they may be misinterpreted as benign lesions despite their primary low malignant behavior and late metastatic potential including the capability to transform into a highly malignant sarcoma. In contrast to high grade osteosarcomas cytogenetic studies of these entities are very rare. Karyotyping including FISH analysis with painting- and centromere-specific probes was done in 2 cases of low grade central osteosarcomas (fibrous dysplasia like type). One case was a primary lesion in the upper femur, the other was a recurrent lesion in the upper humerus. Additionally a static DNA cytometry using Feulgen stained imprints was carried out in both cases. In the first case clonal aberrations with a Robertsonian translocation between chromosomes #14 und #15, balanced translocations including chromosomes #5 and #21, #12 and #20, and a supernumary ring chromosome derived from chromosome #1 were detected in a near diploid karyotype. The second case displayed the development from a DNA-diploid to a DNA-peritetraploid lesion during a follow up of six years. Cytogenetic different marker chromosomes and again ring chromosomes were detected in a near tetraploid karyotype. Low grade central osteosarcomas of fibrous dysplasia like type may be characterized by chromosomal aberrations including ring chromosomes. Regarding the last feature these cytogenetic findings resemble those found in low grade parosteal osteosarcomas and other mesenchymal lesions of borderline behavior or low malignancy grade (for example dermatofibrosarcoma protuberans, low grade liposarcoma).

[Comparative DNA cytometric and cytogenetic ploidy determination of chondrosarcoma and osteosarcoma]. / Vergleichende DNA-zytometrische und zytogenetische Ploidiebestimmungen an Chondrosarkomen und Osteosarkomen.

10 chondrosarcomas and 10 osteosarcomas were examined using cytogenetics and DNA-image-cytometry. Cytogenetically 6 of 10 chondrosarcomas and 4 of 10 osteosarcomas showed hyperdiploid tumorcells. By DNA-cytometry in 8 of 10 chondrosarcomas and 9 of 10 osteosarcomas hyperdiploid tumorcells resp. hyperdiploid stemlines were detected. This discrepancy reflects an in-vitro-selection depending on the different entities. In 7 aneuploid clones of chondrosarcomas the chromosomal ploidy was calculated using the relative length of the chromosomes and compared with the DNA-ploidy of the native tumor. There was a close relation between both parameters of nuclear DNA-content. The interpretation of cytogenetic results is improved using a combination of karyotypic and DNA-cytometric examination. This is particularly important for the search for relations between numeric chromosomal aberrations and morphological parameters (grading).

Self-inflicted hand injuries: diagnostic challenge and treatment.

Self-inflicted injuries are probably more common than is generally appreciated. Three patients with self-inflicted hand injuries are described. A delay in making the correct diagnosis resulted in severe hand disability in 2 of the patients. Early diagnosis of this entity, combined with prompt psychotherapy, prevented disability in the third. The pertinent literature is reviewed and the importance of early diagnosis and psychotherapy is stressed.