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21.
Seven human skeletons from a large assemblage from a rural English Medieval burial site show lesions, predominantly proliferative in nature, on the visceral surfaces of the ribs. In order to investigate whether these rib lesions were regularly associated with tuberculous infection, these individuals, together with a group of age- and sex-matched control skeletons without bony signs of infection, were subjected to polymerase chain reaction (PCR) assays aimed at detecting traces of DNA from infecting microorganisms of the Mycobacterium tuberculosis complex. The results provided no evidence for any regular association between visceral surface rib lesions and the presence of M. tuberculosis complex DNA in the study group. The significance of these findings for the paleopathological interpretation of visceral surface rib lesions is discussed. 相似文献
22.
We report on the measurements of carbon and nitrogen stable isotopes of both bone and teeth from a single site and population (Medieval Wharram Percy), undertaken to explore variations due to weaning in a past population. There have been a number of recent studies of weaning using delta(15)N values of ribs, and we indicate a number of assumptions that must be met before the results of such studies can be correctly interpreted. We found that rib collagen delta(15)N values decrease to adult levels after age 2 years, indicating that weaning occurred at or before this age. Rib collagen delta(13)C values are also more enriched than adult delta(13)C values before age 2 years, and we argue that this is due to the so-called "carnivore" effect in delta(13)C. We measured teeth and rib delta(15)N values from the same individuals and found that for individuals up to age 11 years, tooth dentine delta(15)N is higher than adult rib delta(15)N values, indicating that the dentine was formed during breast-feeding and that there was almost no turnover of dentine since. We observed some decrease in delta(13)C and delta(15)N rib values, compared to adult rib and teeth values, for the few years after weaning that may relate to a theoretically predicted physiological nitrogen imbalance during this period of rapid growth, but this is more likely due to a childhood diet (up to age 9) which was isotopically different from later diet, possibly consisting of a greater proportion of plant foods. 相似文献
23.
Smith M Woodroffe A Smith R Holguin S Martinez J Filipek PA Modahl C Moore B Bocian ME Mays L Laulhere T Flodman P Spence MA 《Cytogenetic and genome research》2002,98(4):233-239
In a sporadic case of autism and language deficit due to auditory processing defects, molecular genetic studies revealed that a chromosomal deletion occurred in the 13q12-->q13 region. No chromosome abnormalities were detected in the parents. We determined that the deletion occurred on the paternally derived chromosome 13. There are two previous reports of chromosome 13 abnormalities in patients with autism. The deletion in the subject described in this paper maps between the two chromosome 13 linkage peaks described by Bradford et al. (2001) in studies of subjects with autism and language deficits. The 9-Mb region deleted in the patient described here contains at least four genes that are expressed in brain and that play a role in brain development. They are NBEA, MAB21L1, DCAMKL1 and MADH9. These genes therefore represent candidate genes for autism and specific language deficits. 相似文献
24.
25.
Sarah A. Inskip G. Michael Taylor Sonia R. Zakrzewski Simon A. Mays Alistair W. G. Pike Gareth Llewellyn Christopher M. Williams Oona Y-C Lee Houdini H. T. Wu David E. Minnikin Gurdyal S. Besra Graham R. Stewart 《PloS one》2015,10(5)
We have examined a 5th to 6th century inhumation from Great Chesterford, Essex, UK. The incomplete remains are those of a young male, aged around 21–35 years at death. The remains show osteological evidence of lepromatous leprosy (LL) and this was confirmed by lipid biomarker analysis and ancient DNA (aDNA) analysis, which provided evidence for both multi-copy and single copy loci from the Mycobacterium leprae genome. Genotyping showed the strain belonged to the 3I lineage, but the Great Chesterford isolate appeared to be ancestral to 3I strains found in later medieval cases in southern Britain and also continental Europe. While a number of contemporaneous cases exist, at present, this case of leprosy is the earliest radiocarbon dated case in Britain confirmed by both aDNA and lipid biomarkers. Importantly, Strontium and Oxygen isotope analysis suggest that the individual is likely to have originated from outside Britain. This potentially sheds light on the origins of the strain in Britain and its subsequent spread to other parts of the world, including the Americas where the 3I lineage of M. leprae is still found in some southern states of America. 相似文献
26.
Resorption of mandibular alveolar bone following loss of molar teeth and its relationship to age at death in a human skeletal population
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Simon Mays 《American journal of physical anthropology》2014,153(4):643-652
Estimating adult age at death in skeletal remains is problematic, particularly in older adults. Molar wear is arguably the most reliable ageing technique for palaeopopulations, but many older adult skeletons have lost their molar teeth ante mortem, precluding its application. Resorption of the alveolar process occurs following tooth loss, and this appears to continue for a prolonged period. The current work investigates the relationship of this process to individual age in a nineteenth century AD European archaeological skeletal series of known age at death (N = 92 individuals), and discusses its potential as an age indicator. Mandibular corpus height was measured at the different molar positions. In females, reduction of corpus height with age was found at molar positions showing ante mortem loss. In both sexes, a relationship was found between age and a simple composite measure of corpus height in the molar region in those showing ante mortem loss of one or more mandibular molars. The correlation was stronger in females (r = ?0.74) than in males (r = ?0.49), appeared approximately linear, and continued into the ninth decade, the oldest age group in the study material. The results suggest that investigation of height of the posterior part of the mandibular corpus as a skeletal age indicator for individuals that have lost one or more molar teeth is merited in other palaeopopulations. Am J Phys Anthropol 153:643–652, 2014. © 2014 Wiley Periodicals, Inc. 相似文献
27.
Xuefei Tan Richland W. Tester Gregory R. Luedtke Sarvajit Chakravarty Babu J. Mavunkel John J. Perumattam Qing Lu Imad Nashashibi Joon Jung Jie Hu Albert Liclican Ramona Almirez Jocelyn Tabora Vinh Tran Maureen Laney Daniel E. Levy Sundeep Dugar 《Bioorganic & medicinal chemistry letters》2010,20(3):828-831
Derivatives of the 4-fluorobenzyl dimethylpiperazine-indole class of p38α MAP kinase inhibitors are described. Biological evaluation of these compounds focused on maintaining activity while improving pharmacokinetic (PK) properties. Improved properties were observed for structures bearing substitutions on the benzylic methylene. 相似文献
28.
Yongsheng Chen Imad Zein Everton Alen Brenner Jeppe Reitan Andersen Mathias Landbeck Milena Ouzunova Thomas Lübberstedt 《BMC plant biology》2010,10(1):12
Background
Reduced lignin content leads to higher cell wall digestibility and, therefore, better forage quality and increased conversion of lignocellulosic biomass into ethanol. However, reduced lignin content might lead to weaker stalks, lodging, and reduced biomass yield. Genes encoding enzymes involved in cell wall lignification have been shown to influence both cell wall digestibility and yield traits. 相似文献29.
Andersen JR Zein I Wenzel G Krützfeldt B Eder J Ouzunova M Lübberstedt T 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2007,114(2):307-319
Forage quality of maize is influenced by both the content and structure of lignin in the cell wall. Phenylalanine Ammonia-Lyase (PAL) catalyzes the first step in lignin biosynthesis in plants; the deamination of L-phenylalanine to cinnamic acid. Successive enzymatic steps lead to the formation of three monolignols, constituting the complex structure of lignin. We have cloned and sequenced a PAL genomic sequence from 32 maize inbred lines currently employed in forage maize breeding programs in Europe. Low nucleotide diversity and excessive linkage disequilibrium (LD) was identified at this PAL locus, possibly reflecting selective constrains resulting from PAL being the first enzyme in the monolignol, and other, pathways. While the association analysis was affected by extended LD and population structure, several individual polymorphisms were associated with neutral detergent fiber (not considering population structure) and a single polymorphism was associated with in vitro digestibility of organic matter (considering population structure). 相似文献
30.
Vaccines based on novel adeno-associated virus vectors elicit aberrant CD8+ T-cell responses in mice
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We recently discovered an expanded family of adeno-associated viruses (AAVs) that show promise as improved gene therapy vectors. In this study we evaluated the potential of vectors based on several of these novel AAVs as vaccine carriers for human immunodeficiency virus type 1 Gag. Studies with mice indicated that vectors based on AAV type 7 (AAV7), AAV8, and AAV9 demonstrate improved immunogenicity in terms of Gag CD8(+) T-cell and Gag antibody responses. The quality of these antigen-specific responses was evaluated in detail for AAV2/8 vectors and compared to results with an adenovirus vector expressing Gag (AdC7). AAV2/8 produced a vibrant CD8(+) T-cell effector response characterized by coexpression of gamma interferon and tumor necrosis factor alpha as well as in vivo cytolytic activity. No CD8(+) T-cell response generated by any of the AAVs was effectively boosted with AdC7, a result consistent with the finding of a relative lack of cells expressing interleukin-2 (IL-2) or a central memory phenotype at 3 months after the prime. The primary response to an AdC7 vaccine differed from that generated by AAVs in that the peak effector response evolved into populations of Gag-specific T cells expressing high levels of cytokines, including IL-2, and with effector memory and central memory phenotypes. A number of mechanisms could be considered to explain the aberrant activation of CD8(+) T cells by AAV, including insufficient inflammatory responses, CD4 help, and/or chronic antigen expression and T-cell exhaustion. Interestingly, the B-cell response to AAV-encoded Gag was quite vibrant and easily boosted with AdC7. 相似文献