Diseased

Distribution by Scientific Domains
Distribution within Medical Sciences

Terms modified by Diseased

  • diseased animals
  • diseased brain
  • diseased cell
  • diseased fish
  • diseased heart
  • diseased individual
  • diseased leaf
  • diseased liver
  • diseased plant
  • diseased site
  • diseased skin
  • diseased states
  • diseased subject
  • diseased tissue
  • diseased tree
  • diseased vessel

  • Selected Abstracts


    Application of in situ detection techniques to determine the systemic condition of lymphocystis disease virus infection in cultured gilt-head seabream, Sparus aurata L.

    JOURNAL OF FISH DISEASES, Issue 2 2009
    I Cano
    Abstract Immunohistochemistry (IHC) and in situ hybridization (ISH) techniques have been used for the detection of lymphocystis disease virus (LCDV) in formalin-fixed, paraffin-embedded tissues from gilt-head seabream, Sparus aurata L. Diseased and recovered fish from the same population were analysed. IHC was performed with a polyclonal antibody against a 60-kDa viral protein. A specific digoxigenin-labelled probe, obtained by PCR amplification of a 270-bp fragment of the gene coding the LCDV major capsid protein, was used for ISH. LCDV was detected in skin dermis and gill lamellae, as well as in several internal organs such as the intestine, liver, spleen and kidney using both techniques. Fibroblasts, hepatocytes and macrophages seem to be target cells for virus replication. The presence of lymphocystis cells in the dermis of the skin and caudal fin, and necrotic changes in the epithelium of proximal renal tubules were the only histological alterations observed in fish showing signs of the disease. [source]


    Identifying Rarer Genetic Variants for Common Complex Diseases: Diseased Versus Neutral Discovery Panels

    ANNALS OF HUMAN GENETICS, Issue 1 2009
    K. Curtin
    Summary The power of genetic association studies to identify disease susceptibility alleles fundamentally relies on the variants studied. The standard approach is to determine a set of tagging-SNPs (tSNPs) that capture the majority of genomic variation in regions of interest by exploiting local correlation structures. Typically, tSNPs are selected from neutral discovery panels - collections of individuals comprehensively genotyped across a region. We investigated the implications of discovery panel design on tSNP performance in association studies using realistically-simulated sequence data. We found that discovery panels of 24 sequenced ,neutral' individuals (similar to NIEHS or HapMap ENCODE data) were sufficient to select well-powered tSNPs to identify common susceptibility alleles. For less common alleles (0.01,0.05 frequency) we found neutral panels of this size inadequate, particularly if low-frequency variants were removed prior to tSNP selection; superior tSNPs were found using panels of diseased individuals. Only large neutral panels (200 individuals) matched diseased panel performance in selecting well-powered tSNPs to detect both common and rarer alleles. The 1000 Genomes Project initiative may provide larger neutral panels necessary to identify rarer susceptibility alleles in association studies. In the interim, our results suggest investigators can boost power to detect such alleles by sequencing diseased individuals for tSNP selection. [source]


    Left ventricular mechanical dyssynchrony is load independent at rest and during endotoxaemia in a porcine model

    ACTA PHYSIOLOGICA, Issue 4 2009
    R. A'roch
    Abstract Aim:, In diseased or injured states, the left ventricle displays higher degrees of mechanical dyssynchrony. We aimed at assessing mechanical dyssynchrony ranges in health related to variation in load as well as during acute endotoxin-induced ventricular injury. Methods:, In 16 juvenile anaesthetized pigs, a five-segment conductance catheter was placed in the left ventricle as well as a balloon-tipped catheter in the inferior vena cava. Mechanical dyssynchrony during systole, including dyssynchrony time in per cent during systole and internal flow fraction during systole, were measured at rest and during controlled pre-load reduction sequences, as well as during 3 h of endotoxin infusion (0.25 ,g kg,1 h,1). Results:, Systolic dyssynchrony and internal flow fraction did not change during the course of acute beat-to-beat pre-load alteration. Endotoxin-produced acute pulmonary hypertension by left ventricular dyssynchrony measures was not changed during the early peak of pulmonary hypertension. Endotoxin ventricular injury led to progressive increases in systolic mechanical segmental dyssynchrony (7.9 ± 1.2,13.0 ± 1.3%) and ventricular systolic internal flow fraction (7.1 ± 2.4,16.6 ± 2.8%), respectively for baseline and then at hour 3. There was no localization of dyssynchrony changes to segment or region in the ventricular long axis during endotoxin infusion. Conclusion:, These results suggest that systolic mechanical dyssynchrony measures may be load independent in health and during acute global ventricular injury by endotoxin. More study is needed to validate ranges in health and disease for parameters of mechanical dyssynchrony. [source]


    Three-dimensional reconstruction of the mucosa from sequential sections of biopsy specimens of patients with ulcerative colitis: Relationship between crypt structure and vascular architecture

    DIGESTIVE ENDOSCOPY, Issue 2 2004
    Hiroo Furukawa
    Background:, In a previous paper, the stereographic reconstruction of the crypt structure of ulcerative colitis using the RATOCK System was described. The relationship between the blood vessels and the crypt structure is the focus of the current paper, using two kinds of tissue staining color in which the color differs. Stereographic images make the relationship between the crypt structure and blood vessel distribution understandable at a glance. Methods:, The methods used here are identical to those described in a previous paper. In the present paper, five cases of ulcerative colitis (UC) are examined. Biopsy specimens were obtained from the diseased, normal, and transitional zones (the area between the normal and diseased zones) from each patient. Three-dimensional reconstruction was created using TRI for Windows (RATOC System Tokyo, Japan) software. In the present paper, two kinds of dyeing method between H&E and monoclonal antibody staining of the tissue was used. It was proven that the distribution of gland and blood vessel is very clear in the 3-D reconstruction shown. Results:, (i) The blood vessels in the normal zones run parallel to the crypt in a regular manner and are almost identical to one another in diameter. (ii) In the transitional and diseased zones, the blood vessels show no clear direction and produce many branches without any apparent order. The blood vessels are, moreover, irregular in diameter. (iii) In short, clear parallelism is lost in both the transitional and diseased zones. Conclusion:, Stereographic reconstruction of endoscopically obtained biopsy specimens of UC-affected tissues makes it possible to understand at a glance the distribution of blood vessels and their relationship to crypts. The relationship of these was clarified by the combined use of two kinds of dyeing method with three-dimensional reconstruction. [source]


    Microbial functional structure of Montastraea faveolata, an important Caribbean reef-building coral, differs between healthy and yellow-band diseased colonies

    ENVIRONMENTAL MICROBIOLOGY, Issue 2 2010
    Nikole E. Kimes
    Summary A functional gene array (FGA), GeoChip 2.0, was used to assess the biogeochemical cycling potential of microbial communities associated with healthy and Caribbean yellow band diseased (YBD) Montastraea faveolata. Over 6700 genes were detected, providing evidence that the coral microbiome contains a diverse community of archaea, bacteria and fungi capable of fulfilling numerous functional niches. These included carbon, nitrogen and sulfur cycling, metal homeostasis and resistance, and xenobiotic contaminant degradation. A significant difference in functional structure was found between healthy and YBD M. faveolata colonies and those differences were specific to the physical niche examined. In the surface mucopolysaccharide layer (SML), only two of 31 functional categories investigated, cellulose degradation and nitrification, revealed significant differences, implying a very specific change in microbial functional potential. Coral tissue slurry, on the other hand, revealed significant changes in 10 of the 31 categories, suggesting a more generalized shift in functional potential involving various aspects of nutrient cycling, metal transformations and contaminant degradation. This study is the first broad screening of functional genes in coral-associated microbial communities and provides insights regarding their biogeochemical cycling capacity in healthy and diseased states. [source]


    Bacteria associated with the rapid tissue necrosis of stony corals

    ENVIRONMENTAL MICROBIOLOGY, Issue 7 2007
    G. M. Luna
    Summary The rapid tissue necrosis (RTN) is a common disease of both wild and captive stony corals, which causes a fast tissue degradation (peeling) and death of the colony. Here we report the results of an investigation carried out on the stony coral Pocillopora damicornis, affected by an RTN-like disease. Total abundance of prokaryotes in tissue samples, determined by epifluorescence microscopy, was significantly higher in diseased than in healthy corals, as well as bacterial counts on MB2216 agar plates. Further experiments performed by fluorescent in situ hybridization using a 16S rDNA Vibrio -specific probe showed that vibrios were significantly more abundant in diseased than in healthy corals. Accordingly, bacterial counts on TCBS agar plates were higher in diseased than in healthy tissues. 16S rDNA sequencing identified as Vibrio colonies from diseased tissues only. Cultivated vibrios were dominated by a single ribotype, which displayed 99% of similarity with Vibrio harveyi strain LB4. Bacterial ribotype richness, assessed by terminal-restriction fragment length polymorphism analysis of the 16S rDNA, was significantly higher in diseased than in healthy corals. Using an in silico software, we estimated that a single terminal restriction fragment, putatively assigned to a Vibrio sp., accounted for >,15% and < 5% of the total bacterial assemblage, in diseased and healthy corals respectively. These results let us hypothesize that the RTN in stony corals can be an infectious disease associated to the presence of Vibrio harveyi. However, further studies are needed to validate the microbial origin of this pathology. [source]


    IL-7 is essential for lymphopenia-driven turnover of colitogenic CD4+ memory T cells in chronic colitis

    EUROPEAN JOURNAL OF IMMUNOLOGY, Issue 10 2009
    Takayuki Tomita
    Abstract We previously demonstrated that IL-7 is essential for the persistence of T-cell-mediated colitis, by showing that adoptive transfer of CD4+CD45RBhigh T cells into IL-7,/,×RAG-1,/, mice did not induce colitis; and that intestinal IL-7 is not essential for this colitis model, by showing that IL-7,/,×RAG-1,/, mice parabiosed with colitic CD4+CD45RBhigh T-cell-transferred RAG-1,/, mice developed colitis. Here, we investigated the role of IL-7 in the maintenance of colitogenic CD4+ T cells by surgically separating these parabionts. Surprisingly, the separated IL-7,/,×RAG-1,/, mice were consistently diseased after separation, although no IL-7 mRNA was detected in the tissues of separated IL-7,/,×RAG-1,/, partners. CD4+ T cells isolated from the separated RAG-1,/, or IL-7,/,×RAG-1,/, mice were then transferred into new RAG-1,/, or IL-7,/,×RAG-1,/, mice. Regardless of the source of donor cells, RAG-1,/, recipients developed colitis, whereas IL-7,/,×RAG-1,/, recipients did not. Collectively, these results demonstrate that IL-7 is essential for lymphopenia-driven turnover of colitogenic CD4+ T cells rather than the maintenance of those cells in established colitic mice. They also provide a basis for the timing of IL-7/IL-7R blockade for the treatment of inflammatory bowel diseases. [source]


    Stimulation of keratinocyte differentiation , a new role for the vanilloid receptor subtype 1 (VR1/TRPV1)?

    EXPERIMENTAL DERMATOLOGY, Issue 2 2005
    Sonja Ständer
    Vanilloids and endogenous cannabinoids mediate their actions via the vanilloid receptor subtype 1 (VR1/TRPV1), a non-selective cation channel, which is widely distributed in the central and peripheral nervous system. Only recently, VR1 has been shown to be expressed in keratinocytes in vitro and in vivo. However, a precise description of VR1 localization in epithelial cells was missing. To determine this, we investigated VR1-immunoreactivity as well as mRNA and protein expression in a series of biopsies from normal, diseased, and capsaicin-treated human skin. VR1 was found in epidermal keratinocytes, the inner root sheet and the infundibulum of hair follicles, differentiated sebocytes, sweat gland ducts, and the secretory portion of eccrine sweat glands upon immunohistochemistry, RT-PCR and Western blot analysis. Interestingly, in diseased skin such as prurigo nodularis, psoriasis vulgaris, and atopic dermatitis, VR1 expression in keratinocytes correlated with the degree of epidermal differentiation. Enhanced VR1 immunoreactivity and protein content was found in prurigo nodularis in which epidermal keratinocytes are highly differentiated. Under effective capsaicin therapy of prurigo nodularis, the epidermis thinned and the distribution pattern of VR1 on epidermal keratinocytes normalized. In psoriasis vulgaris, a disease with disturbed epidermal differentiation, less intense immunostaining for VR1 was observed. This could be confirmed by western blot analysis showing less VR1 protein amount in comparison to prurigo nodularis although histologically both showed a thickened epidermis. In atopic dermatitis, which is characterized by a moderate epidermal hyperplasia only and regular differentiated keratinocytes, VR1 immunoreactivity was unchanged in comparison to normal skin. These findings suggest that VR1 may contribute to regular differentiation of keratinocytes. VR1 activation opens non-selective cation channels with high permeability to calcium, a ion that is crucially important for the synthesis of cornification proteins such as involucrin, fillagrin and loricrin. The role of VR1 in other epithelial cells of appendage structures remains to be determined. In summary, VR1 is widely distributed in the skin suggesting a central role for this receptor not only in nociception but also maturation and function of epithelial cells. [source]


    Expression of vanilloid receptor subtype 1 in cutaneous sensory nerve fibers, mast cells, and epithelial cells of appendage structures

    EXPERIMENTAL DERMATOLOGY, Issue 3 2004
    Sonja Ständer
    Abstract:, The vanilloid receptor subtype 1 (VR1)/(TRPV1), binding capsaicin, is a non-selective cation channel that recently has been shown in human keratinocytes in vitro and in vivo. However, a description of VR1 localization in other cutaneous compartments in particular cutaneous nerve fibers is still lacking. We therefore investigated VR1 immunoreactivity as well as mRNA and protein expression in a series (n = 26) of normal (n = 7), diseased (n = 13) [prurigo nodularis (PN) (n = 10), generalized pruritus (n = 1), and mastocytosis (n = 2)], and capsaicin-treated human skin (n = 6). VR1 immunoreactivity could be observed in cutaneous sensory nerve fibers, mast cells, epidermal keratinocytes, dermal blood vessels, the inner root sheet and the infundibulum of hair follicles, differentiated sebocytes, sweat gland ducts, and the secretory portion of eccrine sweat glands. Upon reverse transcriptase-polymerase chain reaction and Western blot analysis, VR1 was detected in mast cells and keratinocytes from human skin. In pruritic skin of PN, VR1 expression was highly increased in epidermal keratinocytes and nerve fibers, which was normalized after capsaicin application. During capsaicin therapy, a reduction of neuropeptides (substance P, calcitonin gene-related peptide) was observed. After cessation of capsaicin therapy, neuropeptides re-accumulated in skin nerves. In conclusion, VR1 is widely distributed in the skin, suggesting a major role for this receptor, e.g. in nociception and neurogenic inflammation. [source]


    Co-occurrence of the ascomycete Lophodermium piceae and the rust fungus Chrysomyxa abietis in Norway spruce needles

    FOREST PATHOLOGY, Issue 1 2001
    A. Lehtijärvi
    The frequency of needles and the proportion of needle segments infected by Lophodermium piceae were compared in symptomless and Chrysomyxa abietis- infected, 1-year-old needles of Picea abies. In late spring, symptomless needles from both rust-infected and healthy saplings were sampled. In addition, rust-infected, totally chlorotic needles and needles with chlorosis along about half their length from the diseased trees were examined. In all three stands, the proportion of segments infected by L. piceae was larger in the rust-infected half of the needle than in the symptomless half; but the difference was statistically significant in only one of the stands. The proportion of L. piceae -infected segments among the nonrust-infected needles was the same as that found for the uninfected half of rust-infected needles (after correction for size differences). No differences in the proportion of L. piceae -infected segments were found between the totally chlorotic, rust-infected needles and the green needles of diseased or healthy trees. [source]


    Tissue Repair: Wet-Spun Biodegradable Fibers on Conducting Platforms: Novel Architectures for Muscle Regeneration (Adv. Funct.

    ADVANCED FUNCTIONAL MATERIALS, Issue 21 2009
    Mater.
    Bio-synthetic platforms, consisting of a conducting polymer substrate overlaid with aligned biodegradable fibers promote the linear growth (ex vivo) of partially differentiated muscle fibers, consistent with the structural requirements of skeletal muscle in vivo, as described by J. M. Razal et al. on page 3381. The conducting surface facilitates development of electrical stimulation paradigms for optimizing muscle growth and development ex vivo that may potentially be applied to repair diseased or damaged muscle. [source]


    Wet-Spun Biodegradable Fibers on Conducting Platforms: Novel Architectures for Muscle Regeneration

    ADVANCED FUNCTIONAL MATERIALS, Issue 21 2009
    Joselito M. Razal
    Abstract Novel biosynthetic platforms supporting ex vivo growth of partially differentiated muscle cells in an aligned linear orientation that is consistent with the structural requirements of muscle tissue are described. These platforms consist of biodegradable polymer fibers spatially aligned on a conducting polymer substrate. Long multinucleated myotubes are formed from differentiation of adherent myoblasts, which align longitudinally to the fiber axis to form linear cell-seeded biosynthetic fiber constructs. The biodegradable polymer fibers bearing undifferentiated myoblasts can be detached from the substrate following culture. The ability to remove the muscle cell-seeded polymer fibers when required provides the means to use the biodegradable fibers as linear muscle-seeded scaffold components suitable for in vivo implantation into muscle. These fibers are shown to promote differentiation of muscle cells in a highly organized linear unbranched format in vitro and thereby potentially facilitate more stable integration into recipient tissue, providing structural support and mechanical protection for the donor cells. In addition, the conducting substrate on which the fibers are placed provides the potential to develop electrical stimulation paradigms for optimizing the ex vivo growth and synchronization of muscle cells on the biodegradable fibers prior to implantation into diseased or damaged muscle tissue. [source]


    Oral health and morbidity , implications of oral infections on the elderly

    GERODONTOLOGY, Issue 1 2006
    Jukka H. Meurman
    Detrimental effects of oral infections on general health have been known for almost 3000 years. Modern studies, however, have cast new light on the pathogenic mechanisms by which oral infections appear to link with morbidity and mortality. In particular, among the elderly, poor dental health seems to associate with all-cause mortality. This review aims to provide an overview of present knowledge of these issues, starting from dental bacteraemia, oral mucosal infections and problems of drug resistance and, briefly, discussing what is known about the link between oral health and some systemic diseases such as atherosclerosis and type-2 diabetes. The main conclusions are that scientific evidence is still weak on these interactions and that the elderly should be better taken into account when planning future studies. Functions of the body differ in the frail and diseased from those of the young. Consequently, novel prevention and treatment strategies should be developed and properly tested for combating oral infections in elderly populations. Specific suggestions for further research are outlined. [source]


    Advanced Material Strategies for Tissue Engineering Scaffolds

    ADVANCED MATERIALS, Issue 32-33 2009
    Lisa E. Freed
    Abstract Tissue engineering seeks to restore the function of diseased or damaged tissues through the use of cells and biomaterial scaffolds. It is now apparent that the next generation of functional tissue replacements will require advanced material strategies to achieve many of the important requirements for long-term success. Here, we provide representative examples of engineered skeletal and myocardial tissue constructs in which scaffolds were explicitly designed to match native tissue mechanical properties as well as to promote cell alignment. We discuss recent progress in microfluidic devices that can potentially serve as tissue engineering scaffolds, since mass transport via microvascular-like structures will be essential in the development of tissue engineered constructs on the length scale of native tissues. Given the rapid evolution of the field of tissue engineering, it is important to consider the use of advanced materials in light of the emerging role of genetics, growth factors, bioreactors, and other technologies. [source]


    Enhanced formation of advanced oxidation protein products in IBD

    INFLAMMATORY BOWEL DISEASES, Issue 6 2008
    Malgorzata Krzystek-Korpacka PhD
    Abstract Background: Advanced oxidation protein products (AOPPs) are new protein markers of oxidative stress with pro-inflammatory properties, accumulated in many pathological conditions. The issue of their enhanced formation in IBD has not been addressed yet. Methods: The concentration of relative AOPPs (rAOPP; concentration of AOPPs divided by albumin level) were measured in 68 subjects with ulcerative colitis (UC), 50 subjects with Crohn's disease (CD) and 45 healthy volunteers, and related to disease phenotype, clinical and biochemical activity, and therapeutic strategy. Diagnostic utility of rAOPP was evaluated by ROC analysis. Results: In comparison with controls (1.367 ,mol/g), rAOPP were increased in inactive (1.778 ,mol/g, P = 0.053) and active (1.895 ,mol/g, P = 0.013) UC and in active (1.847 ,mol/g, P = 0.003) CD. In CD, but not UC, rAOPP correlated with disease activity (r = 0.42, P = 0.013). Significant correlations with the inflammatory/malnutrition indices-erythrocyte sedimentation rate (ESR) (r = 0.53), leukocytes (r = 0.33), platelets (r = 0.38), IL-6 (r = 0.36), and transferrin (r = ,0.35) were demonstrated in CD. In UC, rAOPP correlated only with ESR (r = 0.35) and IL-6 (r = 0.30). Instead, associations with antioxidant dismutase (r = 0.29) and catalase (r = 0.22) were observed. The diagnostic power of rAOPP in discriminating diseased from non-diseased subjects was less than that of C-reactive protein (CRP). Simultaneous determination of rAOPP and CRP did not significantly improve the power of single CRP determination. Conclusions: IBD was associated with enhanced formation of AOPP, which differed between C and UC with respect to the relationship between rAOPP and disease activity, inflammatory and antioxidant response. These differences may reflect divergent ways that oxidative stress develops in CD and UC. The diagnostic power of rAOPP was insufficient for its clinical application. (Inflamm Bowel Dis 2008) [source]


    Comparison of efficacy criteria across onychomycosis trials: need for standardization

    INTERNATIONAL JOURNAL OF DERMATOLOGY, Issue 4 2003
    Aditya K. Gupta MD, FRCP(C)
    Background The last 10 years have seen a substantial increase in the number of studies reporting the efficacy of the various antifungal agents used to treat onychomycosis. Aim To examine the definitions of efficacy parameters reported in clinical studies on the treatment of onychomycosis and discuss the importance of standardized reporting. Methods We searched MEDLINE (1966,2001) for studies in which oral treatments, griseofulvin, ketoconazole, terbinafine (continuous and pulse), itraconazole (continuous and pulse), and fluconazole, were used to treat dermatophyte onychomycosis. Results Mycologic cure was predominantly defined as negative microscopy and culture. Unlike mycologic cure, clinical parameters (e.g. clinical response, clinical cure) were variably defined. Subjective terms, such as "cure" or "markedly improved," were used; although these terms appear to be explicit, what is considered to be "cured" or "markedly improved" by one evaluator may not be by another. Also, infected nails were clinically evaluated to determine the response to treatment. Studies measured the distance between the proximal nail fold and a notch in the nail plate, at the junction between the diseased and normal-appearing nail, or in some cases estimated the diseased nail plate involvement. Conclusions This review of the literature on systemic agents used to treat onychomycosis shows that standard and explicit definitions are required for the accurate comparison of the effectiveness of the various therapies. [source]


    Infrared Microscopic Imaging of Bone: Spatial Distribution of CO32,

    JOURNAL OF BONE AND MINERAL RESEARCH, Issue 5 2001
    H. Ou-Yang
    Abstract This article describes a novel technology for quantitative determination of the spatial distribution of CO32, substitution in bone mineral using infrared (IR) imaging at ,6 ,m spatial resolution. This novel technology consists of an IR array detector of 64 × 64 elements mapped to a 400 ,m × 400 ,m spot at the focal plane of an IR microscope. During each scan, a complete IR spectrum is acquired from each element in the array. The variation of any IR parameter across the array may be mapped. In the current study, a linear relationship was observed between the band area or the peak height ratio of the CO32, v3 contour at 1415 cm,1 to the PO43, v1,v3 contour in a series of synthetic carbonated apatites. The correlation coefficient between the spectroscopically and analytically determined ratios (R2 = 0.989) attests to the practical utility of this IR area ratio for determination of bone CO32, levels. The relationship forms the basis for the determination of CO32, in tissue sections using IR imaging. In four images of trabecular bone the average CO32, levels were 5.95 wt% (2298 data points), 6.67% (2040 data points), 6.66% (1176 data points), and 6.73% (2256 data points) with an overall average of 6.38 ± 0.14% (7770 data points). The highest levels of CO32, were found at the edge of the trabeculae and immediately adjacent to the Haversian canal. Examination of parameters derived from the phosphate v1,v3 contour of the synthetic apatites revealed that the crystallinity/perfection of the hydroxyapatite (HA) crystals was diminished as CO32, levels increased. The methodology described will permit evaluation of the spatial distribution of CO32, levels in diseased and normal mineralized tissues. [source]


    An improved cost-effective, reproducible method for evaluation of bone loss in a rodent model

    JOURNAL OF CLINICAL PERIODONTOLOGY, Issue 2 2009
    Daniel H. Fine
    Abstract Aim: This study was designed to investigate the utility of two "new" definitions for assessment of bone loss in a rodent model of periodontitis. Material and Methods: Eighteen rats were divided into three groups. Group 1 was infected by Aggregatibacter actinomycetemcomitans (Aa), group 2 was infected with an Aa leukotoxin knock-out, and group 3 received no Aa (controls). Microbial sampling and antibody titres were determined. Initially, two examiners measured the distance from the cemento-enamel-junction to alveolar bone crest using the three following methods; (1) total area of bone loss by radiograph, (2) linear bone loss by radiograph, (3) a direct visual measurement (DVM) of horizontal bone loss. Two "new" definitions were adopted; (1) any site in infected animals showing bone loss >2 standard deviations above the mean seen at that site in control animals was recorded as bone loss, (2) any animal with two or more sites in any quadrant affected by bone loss was considered as diseased. Results: Using the "new" definitions both evaluators independently found that infected animals had significantly more disease than controls (DVM system; p<0.05). Conclusions: The DVM method provides a simple, cost effective, and reproducible method for studying periodontal disease in rodents. [source]


    HHV-6, HHV-7, HHV-8 in gingival biopsies from chronic adult periodontitis patients

    JOURNAL OF CLINICAL PERIODONTOLOGY, Issue 3 2003
    A case, control study
    Abstract Background: Recent reports have suggested that various herpesviruses may be involved in the occurrence and progression of different forms of periodontal disease. Objective: The objective of the present study was to investigate the presence of the novel herpesviruses HHV-6, HHV-7 and HHV-8 in gingival biopsies from patients affected by chronic adult periodontitis. As control, gingival biopsies from periodontally healthy subjects were analysed. Materials and methods: Gingival biopsies were harvested from 23 volunteers: 13 patients affected by chronic adult periodontitis (CAP) and 10 periodontally healthy subjects. Each CAP patient contributed two biopsies involving the epithelium and connective tissue facing the sulcus/periodontal pockets: one biopsy from a site having a probing pocket depth (PPD) 5 mm and presenting with bleeding upon probing (affected site) at the time of biopsy collection, and the other biopsy from a site with PPD3 mm and without bleeding on probing (nonaffected site). After DNA extraction, nested PCR was used in herpesvirus identification. Results: HHV-6 DNA sequences were detected in one non-affected site (8%) and no affected sites (0%) of CAP patients. One biopsy (10%) in healthy subjects revealed HHV-6 positivity. Tissue specimens in 10/13 CAP patients (77%) and 7/10 healthy subjects (70%) contained HHV-7 DNA. HHV-7 prevalence in affected and nonaffected sites of CAP patients was 77% and 54%, respectively. HHV-8 was detected in 7.7% of CAP patients and 0% of healthy subjects. Conclusions: Gingival tissue may act as a reservoir for HHV-7. A high prevalence of HHV-7 was detected in both periodontally diseased and healthy individuals. The prevalence of HHV-6 and -8 was similarly low in both groups. Our data do not support an association of investigated herpesvirus species with destructive periodontal disease. Zusammenfassung Hintergrund: Kürzliche Studien haben angedeutet, dass verschiedene Herpesviren bei der Entstehung und Progression verschiedener Formen der parodontalen Erkrankungen involviert sein könnten. Ziel: Das Ziel der vorliegenden Studie war die Untersuchung einer Präsenz von neuen Herpesviren HHV-6, HHV-7 und HHV-8 in gingivalen Biopsien von Patienten mit chronischer Erwachsenen-Parodontitis. Als Kontrollen dienten gingivale Biopsien von parodontal gesunden Personen. Material und Methoden: Gingivale Biopsien wurden von 23 Freiwilligen, 13 Patienten mit chronischer Erwachsenen-Parodontitis (CAP) und 10 parodontal gesunden Personen gesammelt. Von jedem CAP Patient wurden zwei Biopsien mit Epithel und Bindegewebe von der parodontalen Tasche genommen: eine Biopsie von einer Fläche mit einer Sondierungstiefe (PPD) , 5 mm und positiver Provokationsblutung (geschädigte Fläche) zur Zeit der Biopsieentnahme, die andere Biopsie von einer Fläche mit einer PPD , 3 mm und ohne Provokationsblutung (nicht geschädigte Fläche). Nach der DNA-Extraktion wurde die PCR zur Virusidentifikation benutzt. Ergebnisse: HHV-6 DNA-Sequenzen wurden in einer nicht geschädigten Fläche gefunden (8 %) und bei keiner geschädigten Fläche (0 %) von CAP-Patienten. Eine Biopsie (10 %) bei gesunden Personen war HHV-6 positiv. Gewebeproben von 10/13 CAP Patienten (77 %) und von 7/10 gesunden Personen (70 %) enthielten HHV-7 DNA. Die HHV-7 Prävalenz in geschädigten und nicht geschädigten Flächen von CAP Patienten war 77 % und 54 %. HHV-8 wurde in 7,7 % der CAP Patienten und bei 0 % der gesunden Personen gefunden. Zusammenfassung: Gingivales Gewebe kann als Reservoir für HHV-7 dienen. Eine hohe Prävalenz von HHV-7 wurde sowohl bei parodontal erkrankten als auch bei gesunden Personen gefunden. Das Vorkommen von HHV-6 und HHV-8 war in beiden Gruppen ähnlich. Unsere Daten unterstützen eine Beziehung der untersuchten Herpesviren mit destruierenden parodontalen Erkrankungen nicht. Résumé Des rapports récents ont suggéré que différents virus de l'herpès pouvaient être associés à l'apparition et la progression de différentes formes de la maladie parodontale. Le but de l'étude présente a été d'analyser la présence des virus herpétiques HHV-6, HHV-7 et HHV-8 dans des biopsies gingivales provenant de patients atteints de parodontite chronique de l'adulte. Comme contrôle, des biopsies gingivales de patients sains du point de vue parodontal ont été analysées. Des biopsies gingivales ont été prélevées de 23 volontaires, 13 souffrant de parodontite chronique (CAP) et 10 sains. Chaque patient CAP procuraient deux biopsies comprenant l'épithélium et le tissu conjonctif en face des poches parodontales/sillons : une biopsie provenant d'un site avec une profondeur de poche au sondage (PPD) 5mm et présentant un saignement au sondage (site touché) au moment du prélèvement de la biopsie, l'autre biopsie provenait d'un site avec PPD 3 mm sans saignement au sondage (site sain). Après extraction de l'ADN le PCR a été utilisé pour l'identification des virus herpétiques. Des séquences ADN HHV-6 ont été détectées dans un site sain (8%) mais dans aucun site touché (0%) chez les patients CAP. Une biopsie (10%) chez les sujets sains était HHV-6 positive. Les spécimens tissulaires de dix des treize patients CAP (77%) et sept des dix patients sains (70%) avaient de l'ADNHHV-7. La fréquence globale de HHV-7 dans les sites sains et touchés des patients CAP étaient respectivement de 77 et 54 %. HHV-8 était détecté chez 7,7 % des patients CAP et 0% des patients sains. Le tissu gingival peut servir de réservoir au HHV-7. Une importante fréquence globale de HHV-7 était détectée tant chez les individus sains que chez ceux avec parodontite. La fréquence globale de HHV-6 et HHV-8 était pareillement faible dans les deux groupes. Ces données ne défendent pas la thèse d'une association des virus herpétiques étudiés à la maladie parodontale destructrice. [source]


    Analysis of two common ,1 -antitrypsin deficiency alleles (PI*Z and PI*S) in subjects with periodontitis

    JOURNAL OF CLINICAL PERIODONTOLOGY, Issue 12 2002
    D. A. Scott
    Abstract Background: ,,1 -Antitrypsin deficiency is a genetically determined condition resulting in predisposition to certain inflammatory diseases due to a protease: antiprotease imbalance that is exacerbated by tobacco smoking. Limited evidence suggests that there may be a significant enrichment of mild ,1 -antitrypsin deficiency phenotypes in subjects with chronic inflammatory periodontal disease. Objective: To examine the prevalence of two common ,1 -antitrypsin deficiency alleles (PI*Z and PI*S) in a UK population of subjects with periodontitis. Subjects and methods: The prevalence of PI*M, PI*S and PI*Z allele combinations was determined in 31 subjects with periodontitis and compared with 31 healthy control subjects matched for smoking status, ethnicity, age and gender. ,1 -Antitrypsin genotyping was performed by multiplex real-time fluorescence polymerase chain reaction (PCR) using DNA extracted from whole blood. Results: There was no difference in the proportion of any ,1 -antitrypsin genotype found in the diseased and control populations. Conclusions: We did not find evidence to support an association between mutant PI* alleles and periodontitis in a small, controlled study. Larger studies will be required to clarify the relationship between ,1 -antitrypsin genotype and susceptibility to inflammatory periodontal disease. [source]


    Quantitative analysis of MRP-8 in gingival crevicular fluid in periodontal health and disease using microbore HPLC

    JOURNAL OF CLINICAL PERIODONTOLOGY, Issue 12 2001
    Fionnuala T. Lundy
    Abstract Background: The protein components of GCF can be separated by reverse-phase microbore HPLC on a C18 column with detection on the basis of 214 nm absorbance. A single major symmetrical protein peak eluting with a retention time of 26 min (50% acetonitrile) was evident in gingival crevicular fluid (GCF) from periodontitis patients but not in healthy GCF. This protein was identified as human MRP-8 by N-terminal amino acid sequencing and liquid chromotography quadropole mass spectrometry. Aims: To quantify the amount of MRP-8 detectable in GCF from individual healthy, gingivitis and periodontitis affected sites and to study the relationship, if any, between the levels of this responsive protein and periodontal health and disease. Methods: GCF was sampled (30 s) from healthy, gingivitis, and periodontitis sites in peridontitis subjects (n=15) and from controls (n=5) with clinically healthy gingiva and no periodontitis. Purified MRP-8 was sequenced by Edmann degradation and the phenylthiohydantoin (PTH) amino acid yield determined (by comparison of peak area with external PTH amino acid standards). This value was subsequently used to calculate the relative amount of protein in the peak eluting with a retention time of 26.0 min (MRP-8) in individual GCF chromatograms. Results: Higher levels of MRP-8 were detected in inflammatory sites: periodontitis 457.0 (281.0) ng; gingivitis 413.5 (394.5) ng compared with periodontally healthy sites in diseased subjects 14.6 (14.3) ng and in controls 18.6 (18.5) ng, p=0.003. There was at least 20-fold more MRP-8 in the inflammatory compared with the healthy sites studied. Conclusions: The preliminary data indicate that MRP-8 is present in GCF, with significantly greater amounts present at diseased than healthy sites. A systematic study of the relationship of this protein to periodontal disease could prove useful in further clarifying whether MRP-8 could be a reliable GCF biomarker of gingivitis and periodontitis. Zusammenfassung Grundlagen: Der Proteingehalt des GCF, abgetrennt werden mit einer reversphasigen Microbore-HPLC auf einer C18-Säule mit Detektion auf der Basis der Absorption von 214 nm. Ein einziges symmetrisches Protein-Hauptpeak-Eluat, der mit einer Retentionszeit von 26 Minuten eluiert wurde (50% Acetonnitril) war in gingivalen Sulkusfluid (GCF) von Parodontitispatienten deutlich sichtbar, jedoch nicht im GCF von Gesunden. Dieses Protein wurde mitels N-terminaler Aminosären-Sequenzierung und Flüssigkeits-Chromatographie mit Quadropol-Massenspektrometrie als humanes MRP-8 identifiziert. Ziele: Quantifizierung der Menge an MRP-8, die im GCF von gesunden Personen, Patienten mit Gingivitis und mit Parodontitis nachweisbar ist und Studieren der eventuell möglichen Beziehungen zwischen den Titern dieses Reaktionsproteins und parodontaler Gesundheit bzw. Erkrankung. Methoden: Bei Parodontitispatienten (n=15) wurde das GCF von gesunden Bereichen, sowie von Stellen mit Gingivitis und Parodontitis gewonnen (30 Sek.) sowie bei Kontrollpersonen (n=5) mit klinisch gesunder Gingiva und ohne Parodontitis. Das gereinigte MRP-8 wurde mittels Edman-Degradierung Sequenziert und der Phenyl-Thiohydantoin (PTH) Aminosäure-Yield bestimmt (durch Vergleich der Peakbereiche mit externen PTH Aminosäurestandards). Darauffolgend wurde dieser Wert verwendet, um die relative Menge des Proteins im Peak-Eluat mit einer Retentionszeit von 26.0 Min. (MRP-8) in den individuellen Chromatogrammen zu berechnen. Ergebnisse: An entzündeten Stellen wurden höhere Titer von MRP-8 nachgewiesen: Parodontitis 457.0 (281.0) ng; Gingivitis 413.5 (394.5) ng verglichen mit parodontal gesunden Stellen bei erkrankten Patienten 14.6 (14.3) ng und den Kontrollen 18.6 (18.5) ng, p=0.003. An den entzündeten Stellen gab es im Vergleich mit den gesunden Stellen wenigstens 20 mal mehr MRP-8. Schlußfolgerungen: Die vorläufigen Daten zeigen, daß MRP-8 im GCF vorhanden ist und an erkrankten Stellen signifikant höhere Mengen vorhanden sind, als an gesunden Stellen. Eine systematische Studie der Beziehung dieses Proteins zur Parodondalerkrankung könnte sich als nützlich erweisen, um des weiteren zu klären, ob MRP-8 eine verläßlicher Biomarker für Gingivitis und Parodontitis ist. Résumé Origine: Les composants proéiques du fluide gingival peuvent être séparés par HPLC microbore en phase inverse sur une colonne C18 avec une détection sur une base d'absorption de 214 nm. Un unique pic majeur symétrique ayant un temps de rétention de 26 min (50% acetonitrile) était manifeste dans le fluide gingival (GCF) des patients atteints de parodontite, mais pas chez les patients sans. Cette protéine fut identifiée comme étant l'MRP-8 humaine après séquençage de l'acide aminé N terminal et spectrométrie de masse quadropole par chromatographie liquide. But: L'objectif est de quantifier la quantité de MRP-8 détectable dans le GCF de site sains, atteints de gingivite ou de parodontite et d'étudier, s'il y en a, la relation entre les niveaux de cette réponse protéique et la santé et la maladie parodontale. Méthodes: Le GCF frut prélevé (30 s) dans des sites sains, atteints de gingivite ou de parodontite, chez des sujets atteints de parodontite (n=15) ou chez des contrôles (n=5), ayant une gencive cliniquement saine sans parodontite. Le MRP-8 purifié fut séquencé par dégradation d'Edmann et le débit d'acide aminé phenylthiohydantoine (PTH) déterminé (par comparaison avec la surface de pic avec des standards d'acide aminé PTH externe). Cette valeur fut ensuite utilisée pour calculer la quantité relative de protéine dans le pic avec un temps de rétention de 26.0 mn (MRP-8) sur des chromatogrammes individuels de GCF. Résultats: De plus hauts niveaux de MRP-8 étaints détectés dans les sites inflammatoires: Parodontite 457.0 (281.0) ng; gingivite 413.5 (394.5) ng par rapport aux sites sains des sujets malades 14.6 (14.3) ng et des sujets contrôles 18.6 (18.5) ng, p=0.003. Il y avait au moins 20× plus de MRP-8 dans les sites inflammatoires par rapport au sites sains. Conclusions: Les données préliminaires indiquent que la MRP-8 est présente dans le GCF, en quantité significativement plus importante dans les sites malades. Une étude systèmatique de la relation entre cette protéine et la maladie parodontale pourrait se révéler utile pour encore plus expliciter si MRP-8 pourrait être un biomarqueur fiable du GCF des gingivites et des parodontites. [source]


    Plasma lipid and blood glucose levels in patients with destructive periodontal disease

    JOURNAL OF CLINICAL PERIODONTOLOGY, Issue 8 2000
    Wolfgang Lösche
    Abstract Hyperlipidaemia and hyperglycaemia are major risk factors for cardiovascular disease. In recent years, some evidence has been presented that periodontal disease is associated with an increased risk of cardiovascular disease. To further elucidate this association, we have studied standard blood chemistry variables known as risk markers for cardiovascular disease in periodontally diseased and healthy subjects. We have measured levels of plasma lipids and fasting blood glucose in 39 subjects with moderate periodontal disease (age 50,60 years) and compared the results with those obtained in 40 age- and sex-matched controls. Both groups were systemically healthy according to their medical history. Total cholesterol, low density lipoprotein cholesterol and triglycerides were significantly higher in periodontally diseased subjects by about 8% (p<0.03), 13% (p<0.003) and 39% (p<0.001), respectively, when compared to controls. Although subjects with diabetes were excluded from the study, we found significantly higher blood glucose levels in the patient than in the control group (85±25 versus 73±17 mg/dl; p<0.02). There was also a significantly higher frequency of pathological plasma lipid profiles in the patient than in the control group. The results indicate that hyperlipaemia and pre-diabetes may be associated with periodontal disease in systemically healthy subjects. These data do not allow us to decide, whether periodontal disease causes an increase in hyperlipaemia and in a prediabetic state or whether periodontal disease and cardiovascular disease share hyperlipidaemia and the prediabetic state as common risk factors. [source]


    Demography of American chestnut populations: effects of a pathogen and a hyperparasite

    JOURNAL OF ECOLOGY, Issue 4 2004
    ANITA L. DAVELOS
    Summary 1Matrix models were used to evaluate the effect of chestnut blight infection on transition probabilities and population growth rates for American chestnuts. Disease-free, epidemic and recovering (i.e. pathogen infected with a double-stranded (ds) RNA hypovirus) populations were compared. 2Population growth rates (,) did not differ significantly over time or with disease status. However, predicted stable stage distributions differed between population types, with disease-free and recovering populations more similar to each other than either was to epidemic populations. 3Survival had the highest proportional contribution to population growth rates as revealed by elasticity analyses. However, reductions in stasis of the largest trees contributed most to reductions in population growth rate when comparing diseased with disease-free populations using LTRE. 4The presence of hypovirus reduces pathogen virulence, allowing individual American chestnut trees to increase in size. Where dsRNA has spread, chestnut populations in Michigan have attained population dynamics similar to those found in disease-free populations. 5Matrix models and life table response experiments can be used to detect important pathogen-mediated changes in the dynamics of host populations. [source]


    Male and female Silene latifolia plants differ in per-contact risk of infection by a sexually transmitted disease

    JOURNAL OF ECOLOGY, Issue 1 2001
    Oliver Kaltz
    Summary 1,Behavioural, physiological or immunological constraints often render one sex more susceptible to parasites, thereby potentially generating sex-specific trade-offs between traits associated with infection risk and other life-history characters. 2,The fungal pathogen Microbotryum violaceum systemically infects the dioecious plant Silene latifolia when pollinators deposit fungal spores on the flowers of healthy plants. Male plants produce many short-lived flowers, whereas females produce few flowers that remain connected with the plant after fertilization. We investigated how variation in flower production and flower longevity affects the infection risk for males and females. 3,In glasshouse experiments, we varied the number of flowers inoculated (4 vs. 16 per plant) with spores and the time until these flowers were removed (1 or 2 days for both sexes, 14 days for females only). We also measured the longevity of male flowers receiving simulated visits, with or without spores, to test for an abscission response to visitation and/or contamination. In a field survey, we measured male and female disease prevalence in 17 natural populations. 4,Varying the number of inoculated flowers did not affect infection probability, but females retaining inoculated flowers for 14 days became diseased more often (20.0%) than did plants with flowers removed within 2 days (7.3%). 5,Males that had dropped more inoculated flowers prematurely were more likely to remain uninfected. Spore-bearing visits shortened male flower longevity (38.4 ± 2.8 h) relative to non-spore visits (47.9 ± 5.2 h). 6,Female field disease prevalence (19.7 ± 3.5%) was higher than that of males (14.3 ± 2.6%), especially in populations with a high disease incidence. 7,Continuing physical connection during fruit ripening appears to increase invasion time and thus the per-contact infection risk in females. This is consistent with higher female field prevalences, although other explanations, unrelated to disease transmission, are possible. These results illustrate how interactions between plant reproductive behaviour and pollinator activity may affect disease spread. Female mating behaviour may evolve towards lower attractiveness to pollinators to minimize infectious contacts, while males can afford to be more promiscuous with an attractive, but disposable, floral display. [source]


    Myeloid-related protein (MRP8/14) expression in gingival crevice fluid in periodontal health and disease and after treatment

    JOURNAL OF PERIODONTAL RESEARCH, Issue 4 2010
    E. Andersen
    Andersen E, Dessaix IM, Perneger T, Mombelli A. Myeloid-related protein (MRP8/14) expression in gingival crevice fluid in periodontal health and disease and after treatment. J Periodont Res 2010; 45: 458,463. © 2010 John Wiley & Sons A/S Background and Objective:, Myeloid-related protein (MRP8/14) and its subunits are biomarkers of inflammation. The present study evaluated whether gingival crevice fluid levels of these markers discriminate periodontitis from healthy sites in patients with chronic periodontitis or diseased from healthy subjects, and whether these biomarkers detect longitudinal changes after therapy. Material and Methods:, Levels of MRP8/14, MRP14 and total protein were quantified in 19 periodontitis patients before non-surgical periodontal therapy, after 3 and 6 mo of treatment, and were measured once in 11 periodontally healthy subjects. In total, diseased subjects contributed 59 sites with probing depths >4 mm (PP) and 21 sites <4 mm (PH); healthy subjects contributed 91 sites (HH). Results:, Overall, in diseased subjects, MRP8/14, MRP14 and total protein were not significantly different between PP and PH sites. However, at baseline, MRP8/14 and total protein had significantly higher values at sites in periodontally diseased than in healthy subjects. Clinical improvement was associated with a significant decrease of MRP8/14 and MRP14 from baseline to month 6 in PP sites. Interestingly, a similar decrease was observed in PH sites for all three markers. At 6 mo, however, levels of MRP8/14 and protein in PP and PH sites of patients were still significantly higher than in healthy subjects. Conclusion:, Gingival crevice fluid levels of MRP8/14 did not differentiate between clinically diseased and healthy sites in patients with chronic periodontitis. However, this marker was elevated in periodontally diseased compared with healthy subjects, and its values decreased following therapy. MRP8/14 may be used to monitor the response to treatment. [source]


    A multiplex immunoassay demonstrates reductions in gingival crevicular fluid cytokines following initial periodontal therapy

    JOURNAL OF PERIODONTAL RESEARCH, Issue 1 2010
    D. H. Thunell
    Thunell DH, Tymkiw KD, Johnson GK, Joly S, Burnell KK, Cavanaugh JE, Brogden KA, Guthmiller JM. A multiplex immunoassay demonstrates reductions in gingival crevicular fluid cytokines following initial periodontal therapy. J Periodont Res 2009; doi: 10.1111/j.1600-0765.2009.01204.x. © 2009 John Wiley & Sons A/S Background and Objective:, Cytokines and chemokines play an important role in the pathogenesis of periodontal diseases. The objective of this study was to quantitatively assess the effect of initial periodontal therapy on gingival crevicular fluid levels of a comprehensive panel of cytokines and chemokines, including several less extensively studied mediators. Material and Methods:, Clinical examinations were performed and gingival crevicular fluid samples obtained from six subjects with generalized severe chronic periodontitis prior to initial periodontal therapy and at re-evaluation (6,8 weeks). Four diseased and two healthy sites were sampled in each subject. Twenty-two gingival crevicular fluid mediators were examined using a multiplex antibody capture and detection platform. Statistical analyses were performed by fitting mixed effects linear models to log-transformed gingival crevicular fluid values. Results:, Gingival crevicular fluid interleukin (IL)-1, and IL-1, were the only cytokines to differ in initially diseased vs. initially healthy sites. Following initial therapy, 13 of the 16 detectable cytokines and chemokines decreased significantly in diseased sites, including IL-1,, IL-1,, IL-2, IL-3, IL-6, IL-7, IL-8, IL-12 (p40), CCL5/regulated on activation, normally T cell expressed and secreted (RANTES), eotaxin, macrophage chemotactic protein-1, macrophage inflammatory protein-1, and interferon-,. At healthy sites, only three of the 16 mediators were significantly altered following therapy. Conclusion:, This is the first study, to our knowledge, to evaluate such an extensive panel of gingival crevicular fluid mediators within the same sample prior to and following initial therapy. The results confirm that periodontal therapy effectively reduces pro-inflammatory cytokines and chemokines, including less well-described mediators that may be important in initiation and progression of periodontitis. The multiplex assay will prove useful for future gingival crevicular fluid studies. [source]


    Isolation of Pseudomonas spp. from Diseased Capsicum chinense (Habanero Pepper) Plants in Yucatan, Mexico

    JOURNAL OF PHYTOPATHOLOGY, Issue 7-8 2007
    F. Moguel-Salazar
    Abstract Capsicum chinense (habanero pepper) grown in Yucatan, Mexico, is frequently diseased by plant bacterial pathogens, but the bacterial agents remain unidentified. Bacteria associated with diseased C. chinense were isolated and characterized. Two isolates, ChA11 and ChA14, induced hypersensitive response in C. chinense plantlets and caused rot in C. chinense fruit and potato slices. Molecular identification showed both to be Pseudomonas spp. This is the first report identifying Pseudomonas spp. associated with C. chinense grown in Yucatan, and may represent a first step towards developing control measures against this insidious pathogen. [source]


    Engineering tissues, organs and cells

    JOURNAL OF TISSUE ENGINEERING AND REGENERATIVE MEDICINE, Issue 2 2007
    Anthony Atala
    Abstract Patients suffering from diseased and injured organs may be treated with transplanted organs; however, there is a severe shortage of donor organs that is worsening yearly, given the ageing population. In the field of regenerative medicine and tissue engineering, scientists apply the principles of cell transplantation, materials science and bioengineering to construct biological substitutes that will restore and maintain normal function in diseased and injured tissues. Therapeutic cloning, where the nucleus from a donor cell is transferred into an enucleated oocyte in order to extract pluripotent embryonic stem cells, offers a potentially limitless source of cells for tissue engineering applications. The stem cell field is also advancing rapidly, opening new options for therapy, including the use of amniotic and placental fetal stem cells. This review covers recent advances that have occurred in regenerative medicine and describes applications of these technologies using chemical compounds that may offer novel therapies for patients with end-stage organ failure. Copyright © 2007 John Wiley & Sons, Ltd. [source]


    An in vitro biofilm model of subgingival plaque

    MOLECULAR ORAL MICROBIOLOGY, Issue 3 2007
    C. Walker
    Introduction:, Numerous biofilm models have been described for the study of bacteria associated with the supragingival plaque. However, there are fewer models available for the study of subgingival plaque. The purpose of this study was to develop and validate a model that closely mimicked the composition of the subgingival flora. Methods:, The model was developed as follows: calcium hydroxyapatite disks were coated overnight with 10% sterile saliva, placed in flat-bottomed tissue culture plates containing trypticase-soy broth, directly inoculated with a small aliquot of dispersed subgingival plaque, incubated anaerobically, and transferred to fresh medium at 48-h intervals until climax (steady-state) biofilms were formed (,10 days). Results:, The model, based on samples from eight periodontitis patients and eight healthy subjects, yielded a multi-species, heterogeneous biofilm, consisting of both gram-positive and gram-negative species, and comprising 15,20 cultivable species associated with the subgingival flora. The species present and their proportions were reflective of the initial cultivable subgingival flora. Comparisons of the initial plaque samples from healthy subjects and the mature biofilms showed 81% similarity in species and 70% similarity in the proportions present. Biofilms formed from samples obtained from periodontally diseased subjects were 69% similar in species and 57% similar in the proportions present. Conclusions:, The biofilm model described here closely reproduces the composition of the cultivable subgingival plaque both in the species present and in their relative proportions. Differences existed between biofilms grown from diseased and non-diseased sites with the former being characterized by the presence of periodontal pathogens at microbially significant levels. [source]


    A new checkerboard panel for testing bacterial markers in periodontal disease

    MOLECULAR ORAL MICROBIOLOGY, Issue 1 2006
    G. Dahlén
    Background/aims:, Various microbiological methods have been used for testing bacterial markers for periodontitis and periodontal disease progression. Most studies have used only a limited number of well recognized bacterial species. The purpose of the present study was to evaluate the association of 13 more recently identified bacterial species in a new panel in comparison with 12 previously more recognized periodontotopathogens (,old panel') using the ,checkerboard' DNA,DNA hybridization method. Methods:, Fifty individuals were chosen who showed at least one site with a probing pocket depth of 6 mm or more (disease) and bleeding on probing and at least one site with a probing pocket depth of 3 mm and without bleeding on probing (health). One diseased and one healthy site on each individual were sampled with the paperpoint technique and the samples were processed in the checkerboard technique against deoxigenin-labeled whole genomic probes to 25 subgingival species representing 12 well recognized and 13 newly identified periodontitis associated species. Results:, Twenty-four (out of 25) species were detected more frequently in the subgingival plaque of diseased than healthy sites both at score 1 (> 104) and score 3 (> 105). A significant difference at the higher score (score 3) was noticed for all species of the old panel except for three (Streptococcus intermedius, Selenomonas noxia, and Eikenella corrodens). Of the species in the new panel only Prevotella tannerae, Filifactor alocis, and Porphyromonas endodontalis showed a statistical significant difference between diseased and healthy sites. Conclusion:, It was concluded that P. tannerae, F. alocis, and P. endodontalis should be added to the 12 species used for routine diagnostics of periodontitis-associated bacterial flora. [source]