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1.
J Clin Med ; 10(7)2021 Mar 25.
Article in English | MEDLINE | ID: mdl-33806038

ABSTRACT

This work was aimed to synthetize the evidence available about the relationship between resting heart rate (RHR) and the risk of cancer mortality. A computerized search in the Medline, EMBASE, Web of Science, and Cochrane Library databases from their inception to 24 September 2020 was performed. We performed three meta-analyses: (1) cancer mortality comparing the "less than 60 bpm" and "more than 60 bpm" categories; (2) cancer mortality comparing "less than 60 bpm", "60 to 80 bpm", and "more than 80 bpm" categories; and (3) analysis for 10-12 and 20 bpm increase in RHR and risk of cancer mortality. Twenty-two studies were included in the qualitative review, and twelve of them met the inclusion criteria for the meta-analysis. Our results showed a positive association between RHR and the risk of cancer mortality. This association was shown in a meta-analysis comparing studies reporting mean RHR values below and above 60 bpm, when comparing three RHR categories using less than 60 bpm as the reference category and, finally, in dose response analyses estimating the effect of an increase of 10-12 bpm in RHR, both in men and in women. In conclusion, a low RHR is a potential marker of low risk of cancer mortality.

2.
J Mol Biol ; 432(7): 2405-2427, 2020 03 27.
Article in English | MEDLINE | ID: mdl-32142789

ABSTRACT

Tight junctions regulate paracellular permeability size and charge selectively. Models have been proposed for the molecular architecture of tight junction strands and paracellular channels. However, they are not fully consistent with experimental and structural data. Here, we analysed the architecture of claudin-based tight junction strands and channels by cellular reconstitution of strands, structure-guided mutagenesis, in silico protein docking and oligomer modelling. Prototypic channel- (Cldn10b) and barrier-forming (Cldn3) claudins were analysed. Förster resonance energy transfer (FRET) assays indicated multistep claudin polymerisation, starting with cis-oligomerization specific to the claudin subtype, followed by trans-interaction-triggered cis-polymerisation. Alternative protomer interfaces were modelled in silico and tested by cysteine-mediated crosslinking, confocal- and freeze fracture EM-based analysis of strand formation. The analysed claudin mutants included also mutations causing the HELIX syndrome. The results indicated that protomers in Cldn10b and Cldn3 strands form similar antiparallel double rows, as has been suggested for Cldn15. Mutually stabilising -hydrophilic and hydrophobic - cis- and trans-interfaces were identified that contained novel key residues of extracellular segments ECS1 and ECS2. Hydrophobic clustering of the flexible ECS1 ß1ß2 loops together with ECS2-ECS2 trans-interaction is suggested to be the driving force for conjunction of tetrameric building blocks into claudin polymers. Cldn10b and Cldn3 are indicated to share this polymerisation mechanism. However, in the paracellular centre of tetramers, electrostatic repulsion may lead to formation of pores (Cldn10b) and electrostatic attraction to barriers (Cldn3). Combining in vitro data and in silico modelling, this study improves mechanistic understanding of paracellular permeability regulation by elucidating claudin assembly and its pathologic alteration as in HELIX syndrome.


Subject(s)
Claudin-3/chemistry , Claudins/chemistry , Protein Multimerization , Tight Junctions/chemistry , Animals , Cell Membrane Permeability , Claudin-3/genetics , Claudin-3/metabolism , Claudins/genetics , Claudins/metabolism , HEK293 Cells , Humans , Ion Channels , Mice , Mutation , Protein Conformation , Syndrome , Tight Junctions/metabolism
3.
Eur J Cancer ; 113: 58-68, 2019 05.
Article in English | MEDLINE | ID: mdl-30981949

ABSTRACT

BACKGROUND: Cardiorespiratory fitness is a strong predictor of all-cause morbidity and mortality; nevertheless, the association between cardiorespiratory fitness and the risk of cancer remains unclear. Thus, the aim of this study was to synthetize the evidence on the relationship between cardiorespiratory fitness and the risk of several sites of cancer in men. METHODS: A computerised search in MEDLINE, EMBASE and Web of Science databases from their inception to 13th February 2019 was performed. Both fixed and random-effects models were used to calculate the pooled hazard ratio (HR) estimates and their 95% confidence intervals (CIs) to examine the effect of high and moderate versus low cardiorespiratory fitness on site-specific cancer (lung, colon/rectum, prostate) and all-sites cancer. RESULTS: Ten studies were included in the qualitative review, and seven of them were included in the meta-analysis. Using low cardiorespiratory fitness as the reference group, moderate and high levels of cardiorespiratory fitness were associated with a lower risk (HRs) of lung cancer, 0.53 (95% confidence interval [CI], 0.39 to 0.68) and 0.52 (95% CI, 0.42 to 0.61); colorectal cancer, 0.74 (95% CI, 0.55 to 0.93) and 0.77 (95% CI, 0.62 to 0.92) and all cancer sites, 0.86 (95% CI, 0.79 to 0.93) and 0.81 (95% CI, 0.75 to 0.87), respectively. CONCLUSIONS: Among men, cardiorespiratory fitness plays an important role in protecting against the risk of lung and colorectal cancer. Additionally, this protective effect was observed for all-sites cancer risk. These results show the importance of good cardiorespiratory fitness as a potential factor in cancer prevention.


Subject(s)
Cardiorespiratory Fitness , Colorectal Neoplasms/epidemiology , Lung Neoplasms/epidemiology , Prostatic Neoplasms/epidemiology , Humans , Male , Neoplasms/epidemiology , Proportional Hazards Models
4.
Mucosal Immunol ; 11(2): 345-356, 2018 03.
Article in English | MEDLINE | ID: mdl-28612843

ABSTRACT

In the two inflammatory bowel diseases, ulcerative colitis (UC) and Crohn's disease (CD), altered expression of tight junction (TJ) proteins leads to an impaired epithelial barrier including increased uptake of luminal antigens supporting the inflammation. Here, we focused on regulation of tricellulin (Tric), a protein of the tricellular TJ essential for the barrier against macromolecules, and hypothesized a role in paracellular antigen uptake. We report that Tric is downregulated in UC, but not in CD, and that its reduction increases the passage of macromolecules. Using a novel visualization method, passage sites were identified at TJ regions usually sealed by Tric. We show that interleukin-13 (IL-13), beyond its known effect on claudin-2, downregulates Tric expression. These two effects of IL-13 are regulated by different signaling pathways: The IL-13 receptor α1 upregulates claudin-2, whereas IL-13 receptor α2 downregulates Tric. We suggest to target the α2 receptor in future developments of therapeutical IL-13-based biologicals.


Subject(s)
Colitis, Ulcerative/immunology , Inflammation/immunology , Interleukin-13 Receptor alpha2 Subunit/metabolism , Intestinal Mucosa/physiology , MARVEL Domain Containing 2 Protein/metabolism , Tight Junctions/metabolism , Adult , Aged , Antigens/immunology , Antigens/metabolism , Claudin-2/metabolism , Crohn Disease/immunology , Down-Regulation , Female , HT29 Cells , Humans , Interleukin-13/metabolism , Interleukin-13 Receptor alpha1 Subunit/metabolism , Macromolecular Substances/immunology , Macromolecular Substances/metabolism , Male , Middle Aged , Molecular Targeted Therapy , Signal Transduction , Young Adult
5.
J Public Health (Oxf) ; 38(2): e77-83, 2016 06.
Article in English | MEDLINE | ID: mdl-26199305

ABSTRACT

BACKGROUND: While heavier weight is known to increase the incidence of dyslipidemia, limited data are available on the relationship between weight gain and its development. METHODS: A total of 2647 males were categorized into the following four groups according to the difference between their self-reported weight at 20 years of age and their measured weight in 1994-95: a loss of ≥5% (decrease), loss of <5% or gain of <5% (no change), gain of ≥5 to <15% (increase) and gain of ≥15% (sizable increase). They were followed up until their 2002-03 health examination. Using the 'no change' group as reference, the multivariable-adjusted odds ratio (adjusted for age, body mass index at 20 years of age, physical activity, smoking and alcohol intake) and 95% confidence interval (95% CI) for the incidence of dyslipidemia were determined using logistic regression models. RESULTS: A total of 1342 participants developed dyslipidemia during the follow-up period. The 'increase' and 'sizable increase' groups had odds ratios for the incidence of dyslipidemia of 1.97 (95% CI, 1.59-2.45) and 2.68 (2.15-3.34), respectively, demonstrating that there was a significant dose-response association between weight gain since 20 years of age and the incidence of dyslipidemia (P < 0.001 for trend). CONCLUSION: These results suggest that dyslipidemia could be prevented by avoiding weight gain in adulthood.


Subject(s)
Dyslipidemias/epidemiology , Weight Gain , Weight Loss , Adult , Aged , Alcohol Drinking/epidemiology , Body Weight , Cohort Studies , Exercise , Humans , Incidence , Japan/epidemiology , Logistic Models , Male , Middle Aged , Smoking/epidemiology , Surveys and Questionnaires , Young Adult
6.
Genome Announc ; 3(5)2015 Oct 15.
Article in English | MEDLINE | ID: mdl-26472824

ABSTRACT

"Candidatus Phytoplasma pruni" strain CX, belonging to subgroup 16SrIII-A, is a plant-pathogenic bacterium causing economically important diseases in many fruit crops. Here, we report the draft genome sequence, which consists of 598,508 bases, with a G+C content of 27.21 mol%.

7.
Mol Biol (Mosk) ; 47(1): 94-106, 2013.
Article in Russian | MEDLINE | ID: mdl-23705498

ABSTRACT

The complete nucleotide sequences of more than 100 isolates of PSTVd collected from locations in the territory of Russia and the former USSR have been determined. These sequences represent 42 individual sequence variants, each containing 1-10 mutations with respect to the "intermediate" or type strain of PSTVd (GenBank Acc. No. v01465). Isolates containing 2-5 mutations were the most common, and 24 sequence variants are described here for the first time. Twenty one isolates contained a mutation found only in Russian and Ukrainian isolates of PSTVd up till now; i.e., replacement of the adenine at position 121 with cytosine (A121C). Many of these isolates contained two mutations--deletion of one of the three adenine residues occupying positions 118-120 plus replacement of the adenine at position 121 with either uracil or cytosine (A120, A121U/C). Both combinations of mutations were phenotypically neutral, i.e. symptom expression in Rutgers tomato was unaffected. Phylogenetic analysis of the sequences of different PSTVd isolates presented in work together with sequences of other naturally-occurring isolates obtained from Internet databases suggesting that known PSTVd isolates may be divided into four groups: i) a group of isolates from potato, tomato and solanaceous ornamentals where the type strain of PSTVd (PSTVd.018) may be considered to represent the ancestral sequence, ii) a group of isolates from potato, tomato and solanaceous ornamentals where PSTVd.123 play the same role as PSTVd.018 for the first group, and iii) a group of potato isolates where PSTVd.125 is a possible ancestral sequence. The fourth and most divergent group of PSTVd isolates differs significantly from these first three groups. The majority of isolates in this group originate from New Zealand and Australia and infect different solanaceous hosts (tomato, pepper, cape gooseberry, potato, and others).


Subject(s)
Base Sequence , Plant Diseases , Solanum tuberosum , Viroids , Australia , Genome, Viral , Solanum lycopersicum/genetics , Solanum lycopersicum/virology , Mutation , New Zealand , Phylogeny , Plant Diseases/genetics , Plant Diseases/virology , Russia , Solanum tuberosum/chemistry , Solanum tuberosum/genetics , Solanum tuberosum/virology , Ukraine , Viroids/genetics , Viroids/isolation & purification
8.
Mol Cell Probes ; 27(2): 90-7, 2013 Apr.
Article in English | MEDLINE | ID: mdl-23195601

ABSTRACT

A nested PCR assay was employed to detect the presence of phytoplasmas in 127 blueberry plants exhibiting typical or a portion of blueberry stunt (BBS) syndrome collected in 2010 and 2011, from 11 commercial farms predominantly located in two counties in New Jersey, USA. Ninety plants exhibiting typical stunt syndrome tested positive for phytoplasma infection. Restriction fragment length polymorphism (RFLP) analysis indicated that two distinct phytoplasmas were associated with BBS-diseased plants. About 95% of phytoplasmas detected were very closely related to BBS phytoplasma strains BBS3-AR (subgroup 16SrI-E) and BBS1-MI (unidentified) identified previously, and 4.4% of phytoplasmas detected belonged to the pigeon pea witches'-broom phytoplasma group (16SrIX). Sequence and phylogenetic analysis of cloned 16S rDNA further indicated the subgroup 16SrI-E related phytoplasmas represented a variant of 16SrI-E reference strain BBS3-AR, while the 16SrIX related phytoplasmas were closely related to juniper witches'-broom (JunWB) phytoplasma (16SrIX-E), representing a 16SrIX-E variant. Ribosomal protein (rp) and secY gene-based phylogenies revealed that BBS3-AR and BBS-NJ 16SrI-E strains belonged to a closely related lineage, while BBS-NJ 16SrIX-E strains and JunWB strains represented two distinct lineages. Single nucleotide polymorphisms (SNPs) analyses of rp and secY gene sequences further revealed that no specific rp gene SNPs and only two specific secY gene SNPS were present between BBS-NJ 16SrI-E strains and BBS3-AR. In contrast, BBS-NJ 16SrIX-E strains/clones had 15 consensus rp SNPs and 28 consensus secY SNPs that separated them from JunWB strains/clones. For the first time, two distinct phytoplasmas that cause BBS-disease in the U.S. was revealed.


Subject(s)
Blueberry Plants/microbiology , Phylogeny , Phytoplasma/classification , Phytoplasma/genetics , Polymorphism, Single Nucleotide , Bacterial Proteins/genetics , DNA, Ribosomal , Molecular Sequence Data , New Jersey , Plant Diseases/microbiology , Polymerase Chain Reaction/methods , Polymorphism, Restriction Fragment Length , RNA, Ribosomal, 16S
9.
Nutr Metab Cardiovasc Dis ; 23(1): 17-22, 2013 Jan.
Article in English | MEDLINE | ID: mdl-21982361

ABSTRACT

BACKGROUND AND AIMS: While clinical trials have reported beneficial effects of diet, exercise, and weight loss on incident diabetes in subjects with obesity or impaired glucose tolerance, little is known about the incremental benefit of not smoking and moderate drinking on diabetes risk. We sought to examine the association between modifiable lifestyle factors and residual lifetime risk of diabetes. METHODS AND RESULTS: Prospective cohorts involving 20,915 men (1982-2008) and 36,594 women (1992-2008). Modifiable lifestyle factors and adiposity were ascertained at baseline in each cohort and incident diabetes was ascertained during follow up. The mean age at baseline was 53.5 y in men and 54.6 y in women. During an average follow up of 22.6 y in men and 13.0 y in women, 2096 men and 2390 women developed diabetes. At age 45 y, the residual lifetime risk of diabetes (95% CI) for men with 0, 1, 2, 3, and 4 + healthy lifestyle factors was 30.5 (27.3-33.7); 21.5 (19.9-23.0); 15.1 (13.9-16.3); 10.3 (9.1-11.5); and 7.3 (5.7-8.9) percent; respectively. Corresponding values for women were 31.4 (28.3-34.5); 24.1 (21.8-26.5); 14.2 (12.7-15.7); 11.6 (9.7-13.5); and 6.4 (4.2-8.6) percent, respectively. CONCLUSIONS: These data show an inverse and graded relation between desirable lifestyle factors and residual lifetime risk of diabetes in men and women. Not smoking and moderate drinking may have additional benefits when added to exercise, weight control, and diet.


Subject(s)
Diabetes Mellitus/prevention & control , Risk Reduction Behavior , Alcohol Drinking , Body Weight , Cohort Studies , Diabetes Mellitus, Type 2/epidemiology , Diabetes Mellitus, Type 2/prevention & control , Diet , Exercise , Female , Health Behavior , Humans , Life Style , Male , Middle Aged , Physicians , Prospective Studies , Randomized Controlled Trials as Topic , Risk Factors , Smoking Cessation , Women's Health
10.
Int J Syst Evol Microbiol ; 62(Pt 9): 2279-2285, 2012 Sep.
Article in English | MEDLINE | ID: mdl-22307512

ABSTRACT

The pigeon pea witches'-broom phytoplasma group (16SrIX) comprises diverse strains that cause numerous diseases in leguminous trees and herbaceous crops, vegetables, a fruit, a nut tree and a forest tree. At least 14 strains have been reported worldwide. Comparative phylogenetic analyses of the highly conserved 16S rRNA gene and the moderately conserved rplV (rpl22)-rpsC (rps3) and secY genes indicated that the 16SrIX group consists of at least six distinct genetic lineages. Some of these lineages cannot be readily differentiated based on analysis of 16S rRNA gene sequences alone. The relative genetic distances among these closely related lineages were better assessed by including more variable genes [e.g. ribosomal protein (rp) and secY genes]. The present study demonstrated that virtual RFLP analyses using rp and secY gene sequences allowed unambiguous identification of such lineages. A coding system is proposed to designate each distinct rp and secY subgroup in the 16SrIX group.


Subject(s)
Cytisus , Phylogeny , Phytoplasma/classification , DNA, Bacterial/genetics , Genes, Bacterial , Phytoplasma/genetics , Polymorphism, Restriction Fragment Length , RNA, Ribosomal, 16S/genetics , Sequence Analysis, DNA
11.
Int J Obes (Lond) ; 36(9): 1165-9, 2012 Sep.
Article in English | MEDLINE | ID: mdl-22234277

ABSTRACT

BACKGROUND: Physical activity and adiposity are important predictors of mortality, even in older individuals. However, it is unclear how much physical activity is needed to prevent weight gain in older persons. PURPOSE: To examine the associations of different amounts of physical activity with weight gain prevention in older men. METHODS: A total of 5973 healthy men (mean age, 65.0 years) from the Harvard Alumni Health Study were followed from 1988 to 1998. At baseline (1988), in 1993 and 1998, men reported their recreational physical activity and body weight. Physical activity was categorized as: <7.5 metabolic equivalent (MET)-h per week (7.5 MET-h per week corresponds to the minimum required by the 2008 US federal guidelines), 7.5 to <21 MET-h per week (21 MET-h per week corresponds to the 2002 Institute of Medicine (IOM) guideline) and 21 MET-h per week. Meaningful weight gain was defined as an increase of ≥3% of body weight. RESULTS: Overall, weight tended to be stable over any 5-year period; mean change, -0.08 (s.d.=4.44) kg. However, ∼21% of men experienced meaningful weight gain over any 5-year period. In multivariate analyses, compared with men expending ≥ 21 MET-h per week, those expending 7.5 to <21 MET-h per week had an odds ratio (OR) of 1.35 (95% confidence interval: 1.03, 1.77) for meaningful weight gain, and men expending <7.5 MET-h per week, an OR of 1.16 (1.01, 1.33; P trend=0.09). CONCLUSIONS: Among older men, those with lesser levels of physical activity were more likely to gain weight than men satisfying the 2002 IOM guidelines of ≥21 MET-h per week (∼60 min day(-1) of moderate-intensity physical activity).


Subject(s)
Attitude to Health , Coronary Disease/prevention & control , Exercise , Health Promotion , Obesity/prevention & control , Weight Gain , Aged , Alcohol Drinking/epidemiology , Body Mass Index , Coronary Disease/epidemiology , Coronary Disease/etiology , Coronary Disease/mortality , Diet , Energy Metabolism , Follow-Up Studies , Humans , Male , Obesity/complications , Obesity/epidemiology , Obesity/mortality , Prospective Studies , Risk Factors , Smoking/epidemiology , Surveys and Questionnaires , United States/epidemiology
12.
Ann Oncol ; 23(3): 754-759, 2012 Mar.
Article in English | MEDLINE | ID: mdl-21677311

ABSTRACT

BACKGROUND: The association between adiposity in early adulthood and subsequent development of specific malignancies is unclear. Further, the potential for mediation by adiposity in middle age has not been well examined. In a rare study, we investigated the association of body mass index (BMI) in early adulthood with mortality from several site-specific cancers. DESIGN: In the Harvard Alumni Health Study cohort, 19 593 males had a physical examination at the university between 1914 and 1952 (mean age: 18.4 years) and returned a questionnaire in 1962 or 1966 (mean age = 45.1 years). BMI was computed using weight (kg)/height(2) (m(2)) at both time points. Vital status follow up continued for a maximum of 82 years. RESULTS: Positive early adulthood cancer mortality gradients by BMI were found for all malignancies combined (adjusted hazard ratio [HR] = 1.11; 95% confidence interval [CI]: 1.05-1.17 for a one standard deviation increase in early adulthood BMI), and for lung (HR = 1.24; 95% CI = 1.10-1.40) and skin (HR = 1.29; 95% CI = 0.96-1.75) cancers. There were also apparent associations for cancers of the oesophagus and urogenital sites. Mediation by BMI in middle age was found to be minimal. CONCLUSION: Higher BMI in early adulthood appears to be a direct risk factor for selected malignancies several decades later.


Subject(s)
Adiposity/physiology , Body Mass Index , Neoplasms/mortality , Adolescent , Adult , Cohort Studies , Humans , Male , Middle Aged , Risk Factors , Young Adult
13.
Lett Appl Microbiol ; 53(3): 371-3, 2011 Sep.
Article in English | MEDLINE | ID: mdl-21679200

ABSTRACT

AIMS: To test a performance of the microbiological safety cabinets (MSCs) according to the type of MSCs in microbial laboratories. METHODS AND RESULTS: Tests were carried out to assess the performance of 31 MSCs in 14 different facilities, including six different biological test laboratories in six hospitals and eight different laboratories in three universities. The following tests were performed on the MSCs: the downflow test, intake velocity test, high-efficiency particulate air filter leak test and the airflow smoke pattern test. These performance tests were carried out in accordance with the standard procedures. Only 23% of Class II A1 (8), A2 (19) and unknown MSCs (4) passed these performance tests. The main reasons for the failure of MSCs were inappropriate intake velocity (65%), leakage in the HEPA filter sealing (50%), unbalanced airflow smoke pattern in the cabinets (39%) and inappropriate downflow (27%). CONCLUSIONS: This study showed that routine checks of MSCs are important to detect and strengthen the weak spots that frequently develop, as observed during the evaluation of the MSCs of various institutions. SIGNIFICANCE AND IMPACT OF THE STUDY: Routine evaluation and maintenance of MSCs are critical for optimizing performance.


Subject(s)
Air Microbiology , Laboratories/standards , Filtration , Hospitals , Humans , Republic of Korea , Safety , Universities
14.
Int J Syst Evol Microbiol ; 61(Pt 12): 2822-2826, 2011 Dec.
Article in English | MEDLINE | ID: mdl-21216914

ABSTRACT

A novel phytoplasma, designated strain SoyST1c1, associated with a newly emerging disease in soybean (Glycine max), known as soybean stunt (SoyST), was found in 2002 in a soybean plantation in Alajuela Province, Costa Rica. The same phytoplasma, or a very closely related strain, also infected sweet pepper (Capsicum annuum) with purple vein syndrome (SwPPV) and passion fruit vine (Passiflora edulis) with bud proliferation disease (PasFBP) in the same region. Sequence analysis of cloned 16S rRNA gene sequences (GenBank accession nos FJ226068-FJ226073 and HQ225624-HQ225635) indicated that all three affected plants were infected by phytoplasmas that shared <97.5% sequence similarity with previously described phytoplasmas. The SoyST-causing phytoplasma represents a new taxon, most closely related to phytoplasma group 16SrI and 16SrXII strains. Virtual RFLP analysis indicated that the SoyST-causing phytoplasma and its closely related strains represent a novel 16Sr group, designated 16SrXXXI. Phylogenetic analysis of 16S rRNA gene sequences from the new phytoplasma strains, those previously described as 'Candidatus Phytoplasma spp.' and other distinct, as yet unnamed, phytoplasmas indicated that the SoyST-causing phytoplasma represents a distinct lineage within the aster yellows/stolbur branch on the phylogenetic tree. On the basis of its unique 16S rRNA gene sequence and biological properties, strain SoyST1c1 represents a novel taxon, for which the name 'Candidatus Phytoplasma costaricanum' is proposed with SoyST1c1 as the reference strain.


Subject(s)
Glycine max/microbiology , Phytoplasma/classification , Phytoplasma/isolation & purification , Plant Diseases/microbiology , DNA, Bacterial/genetics , DNA, Ribosomal/genetics , Molecular Sequence Data , Phylogeny , Phytoplasma/genetics , RNA, Ribosomal, 16S/genetics
15.
Int J Syst Evol Microbiol ; 60(Pt 12): 2887-2897, 2010 Dec.
Article in English | MEDLINE | ID: mdl-20097798

ABSTRACT

The secY gene sequence is more variable than that of the 16S rRNA gene. Comparative phylogenetic analyses with 16S rRNA and secY gene sequences from 80 and 83 phytoplasma strains, respectively, were performed to assess the efficacy of these sequences for delineating phytoplasma strains within each 16Sr group. The phylogenetic interrelatedness among phytoplasma taxa inferred by secY gene-based phylogeny was nearly congruent with that inferred by 16S rRNA gene-based phylogeny. Phylogenetic analysis based on the secY gene permitted finer differentiation of phytoplasma strains, however. The secY gene-based phylogeny not only readily resolved 16Sr subgroups within a given 16Sr group, but also delineated distinct lineages irresolvable by 16S rRNA gene-based phylogeny. Such high resolving power makes the secY gene a more useful genetic marker than the 16S rRNA gene for finer differentiation of closely related phytoplasma strains based on RFLP analysis with selected restriction enzymes. Such strains were readily identified by collective secY RFLP patterns. The genetic interrelationships among these strains were determined by pattern similarity coefficients, which coincided with delineations by phylogenetic analysis. This study also revealed two heterogeneous spc operons present in the phytoplasma clade. This latter finding may have significant implications for phytoplasma evolution.


Subject(s)
Phylogeny , Phytoplasma/classification , Bacterial Typing Techniques , Base Sequence , DNA, Bacterial/genetics , Genes, Bacterial , Molecular Sequence Data , Operon , Phytoplasma/genetics , Phytoplasma/isolation & purification , Polymorphism, Restriction Fragment Length , RNA, Ribosomal, 16S/genetics , Sequence Analysis, DNA
16.
Br J Cancer ; 100(4): 611-6, 2009 Feb 24.
Article in English | MEDLINE | ID: mdl-19209175

ABSTRACT

Although an inverse association between physical activity and risk of colon cancer is well established, a formal estimate of the magnitude of this risk reduction that includes recent studies is not available. This analysis examines the association by sex and study design, restricting analyses to studies where data for colon cancer alone were available. The authors reviewed published studies through June 2008 examining the association between physical activity and risk of colon cancer. Heterogeneity and publication bias were evaluated and random effects models used to estimate relative risks (RR). Differences by sex and study design were evaluated. A total of 52 studies were included. An inverse association between physical activity and colon cancer was found with an overall relative risk (RR) of 0.76 (95% confidence interval (CI): 0.72, 0.81). For men, the RR was 0.76 (95% CI: 0.71, 0.82); for women, this was little different, (RR=0.79, 95% CI: 0.71, 0.88). The findings from case-control studies were stronger (RR=0.69, 95% CI: 0.65, 0.74) than for cohort studies (RR=0.83, 95% CI: 0.78, 0.88). This study confirms previous studies reporting an inverse association between physical activity and colon cancer in both men and women, and provides quantitative estimates of the inverse association.


Subject(s)
Colonic Neoplasms/prevention & control , Motor Activity , Adult , Case-Control Studies , Cohort Studies , Colonic Neoplasms/physiopathology , Female , Humans , Male , Middle Aged , Risk Assessment , Risk Factors
17.
Plant Dis ; 93(9): 970, 2009 Sep.
Article in English | MEDLINE | ID: mdl-30754549

ABSTRACT

Potato purple top (PPT) is a devastating disease that occurs in the United States, Canada, Mexico, Russia, and elsewhere causing great economic loss to the potato industry through substantially reduced tuber yield and quality. Chips and fries processed from infected tubers often develop brown discoloration, greatly reducing their marketability. At least seven distinct phytoplasma strains belonging to five different phytoplasma groups (16SrI, 16SrII, 16SrVI, 16SrXII, and 16SrXVIII) have been reported to cause purple top and related symptoms in potato (3). During an unusual drought in 2007, a newly emerging potato disease with extensive yellowish or reddish purple discoloration of terminal shoots and leaves, similar to PPT symptoms, was observed in isolated potato fields in Montana where over 50% of plants exhibited symptoms. Shoot tissues were collected from three symptomatic plants and 17 tubers randomly collected from 17 other symptomatic plants. The tubers were cold treated to induce sprouting and then planted in the greenhouse. All tubers produced plants of which seven exhibited PPT symptoms including severe stunting. Total nucleic acid was extracted from leaf veinal tissue, stolons, or tubers of 10 symptomatic and 10 asymptomatic plants (both field-collected and greenhouse samples) as previously described (3). A nested-PCR assay, using universal primer pair P1/16S-SR followed by R16F2n/R16R2n, was performed as previously described (2,3) to detect phytoplasmas in these samples. Phytoplasma strains were detected in all symptomatic plants. Restriction fragment length polymorphism (RFLP) analyses of nested-PCR products (approximately 1.2 kb) with seven key restriction enzymes (AluI, MseI, HhaI, Tsp509I, HpaII, RsaI, and BfaI) indicated that all samples contained a very similar or identical phytoplasma most closely related to reference strain MW1 (belonging to subgroup 16SrIII-F) (1). Analysis of cloned 16S rDNA sequences confirmed the identity of this new phytoplasma and sequences of three representative PPT-MT strains were deposited in GenBank with Accession Nos. FJ226074-FJ226076. Computer-simulated RFLP analyses of 1.2-kb 16S rDNA sequences of this new phytoplasma and representative members in the peach X-disease phytoplasma group (16SrIII) available in GenBank indicated the strain is distinct and represents a new subgroup, 16SrIII-M (4). This study also indicated that the phytoplasma is tuber transmissible since approximately 35% of plants produced from infected tubers collected in this study developed symptoms. Transmission via infected tubers may pose a potential threat for disease spread by planting uncertified seed potatoes. To our knowledge, this is the first report of 16SrIII group phytoplasmas-associated diseases in potato. A phytoplasma closely related to the PPT-MT strains has recently been detected in potato seedlings exhibiting purple top, rosette, and stunting in Alaska (GenBank Accession No. FJ376628). References: (1) I.-M. Lee et al. Int. J. Syst. Bacteriol. 48:1153, 1998. (2) I.-M. Lee et al. Int. J. Syst. Evol. Microbiol. 54:337, 2004. (3) I.-M. Lee et al. Int. J. Syst. Evol. Microbiol. 56:1593, 2006. (4) W. Wei et al. Int. J. Syst. Evol. Microbiol. 58:2368, 2008.

18.
Plant Dis ; 93(2): 201, 2009 Feb.
Article in English | MEDLINE | ID: mdl-30764130

ABSTRACT

A new soybean disease outbreak occurred in 2002 in a soybean (Glycine max) plantation in Alajuela Province, Costa Rica. Symptoms on the affected plants included general stunting, small leaves, formation of excessive buds, and aborted seed pods. In the same region, two other diseases, one in sweet pepper (Capsicum annuum) fields and another affecting passion fruit (Passiflora edulis) vines, were also found. Symptoms on sweet pepper plants included unusually dark green leaves, some of which exhibited a rugose symptom with a zigzag pattern to the midvein, and purple vein discoloration. Passion fruit vines exhibited bud proliferation. Collectively, symptoms resembled those commonly attributed to phytoplasmal infections. Total nucleic acid was extracted from veinal tissues of leaves or buds (soybean). A nested PCR assay using primer pair P1/P7 followed by R16F2n/R16R2 (1) was employed for the detection of putative phytoplasmas that might be associated within symptomatic plants. All seven symptomatic plants (three soybean, three sweet pepper, and one passion fruit) tested, but not healthy controls, yielded positive results. Restriction fragment length polymorphism (RFLP) analysis of nested PCR products using restriction enzymes AluI, BfaI, HhaI, MseI, and RsaI indicated that the three diseases were associated with a very similar or identical phytoplasma. RFLP patterns and sequence analysis of cloned 16S rDNAs (GenBank Accession Nos. FJ226068-FJ226073) revealed that the phytoplasma shared less than 97.5% sequence homology with all previously classified phytoplasmas, and, as such, represents a new taxon most closely related to 16SrXII group (1) strains. To our knowledge, this is the first report of a new phytoplasma associated with diseases of soybean, sweet pepper, and passion fruit in Costa Rica. Reference: (1) I.-M. Lee et al. Int. J. Syst. Bacteriol. 48:1153, 1998.

19.
Plant Dis ; 93(6): 574-583, 2009 Jun.
Article in English | MEDLINE | ID: mdl-30764398

ABSTRACT

A new disease of potatoes, tentatively named zebra chip (ZC) because of the intermittent dark and light symptom pattern in affected tubers which is enhanced by frying, was first found in Mexico in 1994 and in the southwestern United States in 2000. The disease can cause severe economic losses in all market classes of potatoes. The cause of ZC has been elusive, and only recently has been associated with 'Candidatus Liberibacter' sp. Field samples of potato plants were collected from several locations in the United States, Mexico, and Guatemala to determine transmission to potato and tomato by grafting of ZC-infected scions and psyllid feeding. The disease was successfully transmitted, through up to three generations, by sequential top- and side-grafting ZC-infection scions to several potato cultivars and to tomato. The disease was also successfully transmitted to potato and tomato plants in greenhouse experiments by potato psyllids collected from potato plants naturally affected with ZC. Transmission electron microscopic observation of ZC-affected tissues revealed the presence of bacteria-like organisms (BLOs) in the phloem of potato and tomato plants inoculated by grafting and psyllid feeding. The BLOs were morphologically similar in appearance to BLOs associated with other plant diseases. Polymerase chain reaction (PCR) amplified 16S rDNA sequences from samples representing different geographic areas, including the United States, Mexico, and Guatemala, were almost identical to the 16S rDNA of 'Ca. L. solanacearum' previously reported from solanaceous plants in New Zealand and the United States. Two subclades were identified that differed in two single base-pair substitutions. New specific primers along with an innovative rapid PCR were developed. This test allows the detection of the bacteria in less than 90 min. These data confirm the association of 'Ca. L. solanacearum' with potatoes affected by ZC in the United States, Mexico, and Guatemala.

20.
Int J Electron Healthc ; 4(2): 184-207, 2008.
Article in English | MEDLINE | ID: mdl-18676343

ABSTRACT

This paper presents an overview of the healthcare systems in Southeast Asia, with a focus on the healthcare informatics development and deployment in seven countries, namely, Singapore, Cambodia, Malaysia, Thailand, Laos, the Philippines and Vietnam. Brief geographic and demographic information is provided for each country, followed by a historical review of the national strategies for healthcare informatics development. An analysis of the state-of-the-art healthcare infrastructure is also given, along with a critical appraisal of national healthcare provisions.


Subject(s)
Medical Informatics/organization & administration , Telemedicine/organization & administration , Asia, Southeastern , Cross-Cultural Comparison , Decision Support Systems, Clinical/organization & administration , Delivery of Health Care/organization & administration , Hospital Information Systems/organization & administration , Humans , Medical Informatics/methods , Medical Records Systems, Computerized/organization & administration , Telemedicine/methods
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