Analysis of the beta-globin gene in DNA of suspected thalassemic great apes

DNA was recovered from teeth of 2 great ape skeletons, Pan troglodytes (Ptr) and Pongo pygmaeus (Ppy), belonging to a 19th-century zoological collection. The skeletons presented morphological alterations possibly associated with \u3b2-thalassemia: Ptr had deformation of the calvaria and oro-maxillo-facial bones with porotic hyperostosis and extended osteoporotic lesions of the skeleton, while Ppy showed a general marked widening of the calvarial diploe but moderate osteoporotic signs on the post-cranial skeleton. We screened Ptr and Ppy for mutations in the \u3b2-globin gene (exons 1, 2, and 3) because we suspected thalassemia. Ptr \u3b2-globin sequences showed the highest degree of similarity with the human ones (99.8%), while those of Ppy were slightly different (98.2%). The results were consistent with the phylogenetic relationships between their \u3b2-globin gene sequences. We did not find any mutation in the \u3b2-globin gene of Ptr and Ppy; therefore, we conclude that, in spite of skeletal alterations, the 2 subjects analyzed were not affected by \u3b2-thalassemia

An increased micronucleus frequency in peripheral blood lymphocytes predicts the risk of cancer in humans

The frequency of micronuclei (MN) in peripheral blood lymphocytes (PBL) is extensively used as a biomarker of chromosomal damage and genome stability in human populations. Much theoretical evidence has been accumulated supporting the causal role of MN induction in cancer development, although prospective cohort studies are needed to validate MN as a cancer risk biomarker. A total of 6718 subjects from of 10 countries, screened in 20 laboratories for MN frequency between 1980 and 2002 in ad hoc studies or routine cytogenetic surveillance, were selected from the database of the HUman MicroNucleus (HUMN) international collaborative project and followed up for cancer incidence or mortality. To standardize for the inter-laboratory variability subjects were classified according to the percentiles of MN distribution within each laboratory as low, medium or high frequency. A significant increase of all cancers incidence was found for subjects in the groups with medium (RR = 1.84; 95% CI: 1.28-2.66) and high MN frequency (RR = 1.53; 1.04-2.25). The same groups also showed a decreased cancer-free survival, i.e. P = 0.001 and P = 0.025, respectively. This association was present in all national cohorts and for all major cancer sites, especially urogenital (RR = 2.80; 1.17-6.73) and gastro-intestinal cancers (RR = 1.74; 1.01-4.71). The results from the present study provide preliminary evidence that MN frequency in PBL is a predictive biomarker of cancer risk within a population of healthy subjects. The current wide-spread use of the MN assay provides a valuable opportunity to apply this assay in the planning and validation of cancer surveillance and prevention programs

Intra- and inter-laboratory variation in the scoring of micronuclei and nucleoplasmic bridges in binucleated human lymphocytes. Results of an international slide-scoring exercise by the HUMN project.

One of the objectives of the HUman MicroNucleus (HUMN) project is to identify the methodological variables that have an important impact on micronucleus (MN) or micronucleated (MNed) cell frequencies measured in human lymphocytes using the cytokinesis-block micronucleus assay, In a previous study we had shown that the scoring criteria used were likely to be an important variable. To determine the extent of residual variation when laboratories scored cells from the same cultures using the same set of standard scoring criteria, an inter-laboratory slide-scoring exercise was performed among 34 laboratories from 21 countries with a total of 51 slide scorers involved. The results of this StUdy show that even under these optimized conditions there is a great variation in the MN frequency or MNed cell frequency obtained by individual laboratories and scorers. All laboratories ranked correctly the MNed cell frequency in cells from cultures that were unirradiated, or exposed to 1 or 2 Gy of gamma rays. The study also estimated that the intra-scorer median coefficient of variation for duplicate MNed cell frequency scores is 29% for unexposed cultures and 14 and 11% for cells exposed to I and 2 Gy, respectively, These values can be used as a standard for quality or acceptability of data in future studies. Using a Poisson regression model it was estimated that radiation dose explained 67% of the variance, while staining method. cell sample, laboratory, and covariance explained 0.6, 0.3, 6.5. and 25.6% of the variance, respectively, leaving only 3.1% of the variance unexplained. As part of this exercise. nucleoplasmic bridges were also estimated by the laboratories however, inexperience in the use of this biomarker of chromosome rearrangement was reflected in the much greater heterogeneity in the data and the unexplained variation estimated by the Poisson model. The results of these studies indicate clearly that even after standardizing culture and scoring conditions it will be necessary to calibrate scorers and laboratories if MN, MNed cell and nucleoplasmic bridge frequencies are to be reliably compared among laboratories and among populations. (C) 2002 Elsevier Science B.V. All rights reserved

Intra- and inter-laboratory variation in the scoring of micronuclei and nucleoplasmic bridges in binucleated human lymphocytes. Results of an international slide-scoring exercise by the HUMN project.

One of the objectives of the HUman MicroNucleus (HUMN) project is to identify the methodological variables that have an important impact on micronucleus (MN) or micronucleated (MNed) cell frequencies measured in human lymphocytes using the cytokinesis-block micronucleus assay, In a previous study we had shown that the scoring criteria used were likely to be an important variable. To determine the extent of residual variation when laboratories scored cells from the same cultures using the same set of standard scoring criteria, an inter-laboratory slide-scoring exercise was performed among 34 laboratories from 21 countries with a total of 51 slide scorers involved. The results of this StUdy show that even under these optimized conditions there is a great variation in the MN frequency or MNed cell frequency obtained by individual laboratories and scorers. All laboratories ranked correctly the MNed cell frequency in cells from cultures that were unirradiated, or exposed to 1 or 2 Gy of gamma rays. The study also estimated that the intra-scorer median coefficient of variation for duplicate MNed cell frequency scores is 29% for unexposed cultures and 14 and 11% for cells exposed to I and 2 Gy, respectively, These values can be used as a standard for quality or acceptability of data in future studies. Using a Poisson regression model it was estimated that radiation dose explained 67% of the variance, while staining method. cell sample, laboratory, and covariance explained 0.6, 0.3, 6.5. and 25.6% of the variance, respectively, leaving only 3.1% of the variance unexplained. As part of this exercise. nucleoplasmic bridges were also estimated by the laboratories however, inexperience in the use of this biomarker of chromosome rearrangement was reflected in the much greater heterogeneity in the data and the unexplained variation estimated by the Poisson model. The results of these studies indicate clearly that even after standardizing culture and scoring conditions it will be necessary to calibrate scorers and laboratories if MN, MNed cell and nucleoplasmic bridge frequencies are to be reliably compared among laboratories and among populations. (C) 2002 Elsevier Science B.V. All rights reserved

The role of sleep in pain and fibromyalgia

Fibromyalgia is a common cause of chronic widespread pain, characterized by reduced pressure pain thresholds with hyperalgesia and allodynia. In addition to pain, common symptoms include nonrestorative sleep, fatigue, cognitive dysfunction, stiffness and mood disturbances. The latest research indicates that the dominant pathophysiology in fibromyalgia is abnormal pain processing and central sensitization. Neuroimaging studies have shown that patients with fibromyalgia have similar neural activation to healthy age-matched and gender-matched individuals; however, they have a lower pressure-pain threshold. Polysomnography data has demonstrated that these patients have reduced short-wave sleep and abnormal α-rhythms, suggestive of wakefulness during non-REM (rapid eye movement) sleep. Sleep deprivation in healthy individuals can cause symptoms of fibromyalgia, including myalgia, tenderness and fatigue, suggesting that sleep dysfunction might be not only a consequence of pain, but also pathogenic. Epidemiological studies indicate that poor sleep quality is a risk factor for the development of chronic widespread pain among an otherwise healthy population. Mechanistically, sleep deprivation impairs descending pain-inhibition pathways that are important in controlling and coping with pain. Clinical trials of pharmacological and nonpharmacological therapies have shown that improving sleep quality can reduce pain and fatigue, further supporting the hypothesis that sleep dysfunction is a pathogenic stimulus of fibromyalgi