The effects of colony-stimulating factor-1 on the number and ultrastructure of osteoclasts in toothless (tl) rats and osteopetrotic (op) mice

The role of colony-stimulating factor-1 (CSF-1 or M-CSF) in osteoclast development is illustrated by observations that administration of exogenous CSF-1 increases osteoclast number and improves the skeletal sclerosis of two osteopetrotic mutations, toothless (tl) in the rat and osteopetrotic (op) in the mouse. We examined the effects of CSF-1 treatment on the number and ultrastructure of osteoclasts in the tibial metaphysis of normal and mutant animals of both stocks to understand the similarities and differences between these two mutations. Osteoclasts from normal animals of both stocks were abundant and possessed the ultrastructural features of active cells. These included apical areas in contact with mineralized surfaces with tightly apposed clear zones, extensive ruffled borders, and a vacuolated cytoplasm with numerous mitochondria. In toothless rats osteoclasts were difficult to locate and those present had poorly defined ruffled borders, fewer cytoplasmic vacuoles, and a basal membrane with both smooth and ruffled areas. Large lipid accumulations were often found near tl osteoclasts. Osteoclasts in op mice were difficult to find, but more numerous than in tl rats. Unlike tl osteoclasts, those of op mice possessed very well developed ruffled borders, small clear zones, and large electron-dense cytoplasmic inclusions. These cells also had unusual basal membranes with both smooth and ruffled regions. CSF-1 treatment increased the number of osteoclasts in both mutant stocks, normalizing the numbers in op mice, but not tl rats. CSF-1 injections caused dramatic changes in the morphology of tl osteoclasts, including increased incidence and size of ruffled borders and cytoplasmic vacuolization. The growth factor had little effect on ruffled borders or clear zones in op mice. Interestingly, mutant osteoclasts of both stocks exhibited a ruffled basal membrane in response to CSF-1 treatment. This increase in membrane ruffling may reflect the ability of CSF-1 to promote rapid formation of osteoclasts from mononuclear precursors in a more permissive microenvironment. Our data indicate that CSF-1 is not required for the development of at least some osteoclasts. The differences in response to CSF-1 treatment which we report lead us to speculate that additional factors may be involved in osteoclastogenesis.     

MUC2 gene suppression in human colorectal carcinomas and their metastases: in vitro evidence of the modulatory role of DNA methylation

The development of the majority of colorectal carcinomas is associated with a diminished expression of the intestinal mucin MUC2 in the tumor cells. The significance and the mechanism of this alteration are not yet known. We sought to determine the molecular basis of this tumor-associated change and to investigate the extent to which it might also relate to metastases. MUC2 gene expression was compared in normal (N), carcinomatous (T), and metastatic tissues (M) from nine patients by immunohistochemistry, in situ hybridization, and Northern blotting. Immunohistochemistry and in situ hybridization showed consistently lower amounts of the expressed protein and mRNA in T and in M than in N; quantitative analysis by Northern blotting confirmed that the differences between MUC2 mRNA expression between N, T, and M were significant, the expression in metastases being less than 5% of that in the normal colonic tissue. The influence of DNA methylation as a possible regulatory mechanism of MUC2 gene expression was tested after the 5' and 3'-regions flanking the first exon of MUC2 were recovered from a genomic DNA library and used as probes in Southern blot. The DNA was isolated from colon carcinoma cell lines expressing MUC2 strongly (LS174T) or moderately (T84) and from that which was nonexpressing (Colo 205), and it was digested with the methylation-sensitive enzyme HpaII. The Southern blot patterns indicated that the increased methylation in the promoter region was concomitant with the decrease of MUC2 mRNA expression. Methylation of the promoter region ligated into a reporter vector suppressed the expression of the luciferase reporter gene in the three investigated cell lines. Furthermore, the expression of MUC2 gene was enhanced by treating the MUC2-expressing colon carcinoma cells with 5-aza-2'-deoxycytidine, a methylation-inhibiting agent. To our knowledge this is the first report to show that: (a) MUC2 gene is strongly suppressed in liver and lymph node metastases of colorectal carcinomas, and (b) suppression of MUC2 gene in colon carcinoma cells in vitro is associated with methylation of the promoter region.     

Diabetic cystopathy presenting as primary acute urinary retention in a previously undiagnosed young male diabetic patient

Lower genito-urinary problems are part of the polyneuropathy of diabetes. Cystopathy affects 40%-85% of diabetic patients, although less than half are symptomatic. We report on a 42-year-old patient who was not known to be diabetic, and who presented to the urologists with primary acute urinary retention. His underlaying disease was detected by a test for random blood glucose. More common causes were excluded with careful clinical and radiological examinations. He was managed with insulin and self-catheterization. Diabetes should be considered as a differential diagnosis in relatively young men who present with unexplained acute urinary retention.     

Immunohistochemical localization of novel CART peptides in rat hypothalamus, pituitary and adrenal gland

CART peptide specific polyclonal antisera were raised in rabbits. The antisera were raised to CART peptide fragments that span most of the predicted CART protein. The specificity of each antisera was demonstrated by blockade of immunostaining by the immunizing peptide but not by the other CART peptide fragments. In the hypothalamus and pituitary of colchicine and noncolchicine treated rats, immunostaining was observed in cell bodies, fibers and varicosities. Clusters of cells were also stained in the adrenal medulla. It is noteworthy that cellular immunostaining was only found in areas previously shown to express CART mRNA. These findings indicate the presence of CART peptide(s) in the hypothalamus, pituitary, and adrenal gland. Furthermore, we also present evidence for the possible processing of the CART pro-peptide into smaller peptide fragments. These neuroanatomical findings suggest a role of CART peptides in hypothalamic, pituitary and adrenal function.     

Retinoic acid receptor gamma1 expression determines retinoid sensitivity in pancreatic carcinoma cells

A highly enriched spindle pole preparation was prepared from budding yeast and fractionated by SDS gel electrophoresis. Forty-five of the gel bands that appeared enriched in this fraction were analyzed by high-mass accuracy matrix-assisted laser desorption/ ionization (MALDI) peptide mass mapping combined with sequence database searching. This identified twelve of the known spindle pole components and an additional eleven gene products that had not previously been localized to the spindle pole. Immunoelectron microscopy localized eight of these components to different parts of the spindle. One of the gene products, Ndc80p, shows homology to human HEC protein (Chen, Y., D.J. Riley, P-L. Chen, and W-H. Lee. 1997. Mol. Cell Biol. 17:6049-6056) and temperature-sensitive mutants show defects in chromosome segregation. This is the first report of the identification of the components of a large cellular organelle by MALDI peptide mapping alone.     

Aging on the input versus output side: Theoretical implications of age-linked asymmetries between detecting versus retrieving orthographic information.

This experiment tested for age-linked asymmetries predicted under Node Structure theory (NST; D.G. MacKay & D. M. Burke, 1990) between detecting versus retrieving orthographic information. Older adults detected that briefly presented words were correctly spelled (e.g., endeavor) or misspelled (e.g., endeavuor) as readily as did young adults. However, they were less able than young adults to retrieve the correctly and incorrectly spelled words that they had seen. These age-linked asymmetries were not due to educational factors, stimulus characteristics, sensory-level factors, task complexity, floor or ceiling effects, general slowing, or cohort-related activities, but they were consistent with NST predictions and with similar asymmetries in a wide range of other studies. By contrast, repetition deficits in detecting and retrieving repeated- versus unrepeated-letter misspellings (e.g., elderdly vs. elderkly) were symmetrical or equivalent in magnitude for young and older adults. Implications for a wide range of theories of cognitive aging and of repetition deficits are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

"Age-linked declines in retrieving orthographic knowledge: Empirical, practical, and theoretical implications": Correction to MacKay and Abrams (1998).

Reports an error in "Age-linked declines in retrieving orthographic knowledge: Empirical, practical, and theoretical implications" by Donald G. MacKay and Lise Abrams (Psychology and Aging, 1998[Dec], Vol 13[4], 647-662). The article contained an error. In Table 1 on page 652, the values for rated spelling ability at age 20 and at current age were reversed for older and oldest adults. The corrected table is included in the erratum, with values that have been changed in bold. (The following abstract of the original article appeared in record 1998-11674-011.) This study developed and tested a Transmission Deficit hypothesis of how aging affects retrieval of orthographic knowledge. Young, older, and very old adults heard a tape-recorded series of difficult-to-spell words of high and low frequency, spoken slowly, clearly and repeatedly, and wrote down each word at their own pace. With perceptual errors and vocabulary differences factored out, misspellings increased with aging, especially for high-frequency words. In addition, data from a metamemory questionnaire indicated that the oldest adults were aware of their declining ability to spell. These findings were not due to general slowing, educational factors, hours per week spent reading, writing, or solving crossword puzzles, or age-linked declines in monitoring or detecting self-produced errors. However, the results fit Transmission Deficit predictions, and suggested an age-linked decline in retrieval of orthographic knowledge that resembles age-linked declines in spoken word retrieval observed in many other studies. Practical implications of this age-linked decline for conceptions of normal aging are noted. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Enantioselective antiplatelet actions of nipecotamides

This investigation retrospectively examined changes in marital satisfaction following stroke. The relationship between such changes and other pertinent factors were also examined, including severity of aphasia, knowledge of aphasia, number of months after stroke, and length of the marriage. The subjects were 40 spouses of patients with aphasia grouped according to severity of the aphasia (mild, moderate, severe). Spouses completed two different measures of marital satisfaction--the Marital Satisfaction Scale (MSS) and the Marital Comparison Level Index (MCLI). These measures were completed in both a prestroke (retrospective reporting) and a poststroke format to allow for change to be assessed. In addition, a Knowledge of Aphasia questionnaire was completed by the normal spouses to evaluate their understanding of the disorder of aphasia. There was a significant difference between prestroke and poststroke scores on both the MSS and the MCLI, indicating a lower level of satisfaction following the stroke. The amount of change between prestroke and poststroke MSS and MCLI scores was not related to either number of months poststroke or number of years married. Although there was no relationship between changes in prestroke and poststroke scores on the MCLI and Knowledge of Aphasia scores, there was a significant correlation between changes in these scores on the MSS and Knowledge of Aphasia scores. Hence, the more knowledge spouses had regarding aphasia, the less the negative impact the stroke had on marital satisfaction, as measured by the MSS. Results are discussed in terms of the interdisciplinary treatment needs of aphasic patients and the implications for future investigations.     

The development of γ-γ′ lamellar structures in a nickel-base superalloy during elevated temperature mechanical testing

Changes in the morphology of the γ′ precipitate were examined during creep and tensile testing at temperatures between 927 and 1038 °C in [001]-oriented single crystals of a model Ni-Al-Mo-Ta superalloy. In this alloy, the γ′ particles link together to form lamellae, or rafts, which are aligned with their broad faces perpendicular to the applied tensile axis. The dimensions of the γ and γ′ phases were measured as the lamellar structure developed and were related to time and strain in an attempt to trace the changing γ-γ′ morphology. The results showed that directional coarsening of γ′ began during primary creep, and the attainment of a fully developed lamellar structure did not appear to be directly related to the onset of steady-state creep. The rate of directional coarsening during creep increased as the temperature was raised and also increased as the stress level was raised at a given testing temperature. The raft thickness remained equal to the initial γ′ size from the start of the creep test up through the onset of tertiary creep for all testing conditions. It was found that extensive rafts did not develop during the shorter testing times of the tensile tests, and that tensile testing of pre-rafted structures did not alter the morphology of the rafts. The overall behavior of the alloy was a clear indication of the stability of the finely-spaced γ-γ′ lamellar structure.