Sunday, August 19, 2007



UNUSUAL BACTERIA FOUND IN CROHN'S DISEASE PATIENTS

The abstract below is very technical but any light on Crohn's disease (a not uncommon but still largely mysterious bowel-rotting disease) is worth examination. It was found that an unusual (mutant?) strain of the common bacterium E.coli was present in a small group of patients but not in controls. Whether the bacteria concerned were a cause or an effect is unresolved but a causative role seems somewhat more likely

Culture independent analysis of ileal mucosa reveals a selective increase in invasive Escherichia coli of novel phylogeny relative to depletion of Clostridiales in Crohn's disease involving the ileum

By Martin Baumgart et al.

Abstract

Intestinal bacteria are implicated increasingly as a pivotal factor in the development of Crohn's disease, but the specific components of the complex polymicrobial enteric environment driving the inflammatory response are unresolved. This study addresses the role of the ileal mucosa-associated microflora in Crohn's disease. A combination of culture-independent analysis of bacterial diversity (16S rDNA library analysis, quantitative PCR and fluorescence in situ hybridization) and molecular characterization of cultured bacteria was used to examine the ileal mucosa-associated flora of patients with Crohn's disease involving the ileum (13), Crohn's disease restricted to the colon (CCD) (8) and healthy individuals (7). Analysis of 16S rDNA libraries constructed from ileal mucosa yielded nine clades that segregated according to their origin (P<0.0001). 16S rDNA libraries of ileitis mucosa were enriched in sequences for Escherichia coli (P<0.001), but relatively depleted in a subset of Clostridiales (P<0.05). PCR of mucosal DNA was negative for Mycobacterium avium subspecies paratuberculosis, Shigella and Listeria. The number of E. coli in situ correlated with the severity of ileal disease (rho = 0.621, P<0.001) and invasive E. coli was restricted to inflamed mucosa. E. coli strains isolated from the ileum were predominantly novel in phylogeny, displayed pathogen-like behavior in vitro and harbored chromosomal and episomal elements similar to those described in extraintestinal pathogenic E. coli and pathogenic Enterobacteriaceae. These data establish that dysbiosis of the ileal mucosa-associated flora correlates with an ileal Crohn's disease (ICD) phenotype, and raise the possibility that a selective increase in a novel group of invasive E. coli is involved in the etiopathogenesis to Crohn's disease involving the ileum.

The ISME Journal, 12 July 2007





WALKING REALLY IS GOOD FOR YOU

There is no doubt that high blood pressure is a warning sign so the slight reduction in blood pressure shown below is encouraging. Somewhat amusing that the wicked cholesterol appears to have been unaffected, though. Popular summary below followed by journal abstract

Thirty minutes of walking three times a week may be enough to help lower blood pressure and start you on the path to better health. A new study shows that even a little bit of weekly exercise is enough to lower blood pressure and improve overall fitness. The results showed that 30 minutes of walking three times a week - even if it was broken into 10-minute walks throughout the day - was enough to have a healthy effect on blood pressure as well as measurements around the waist and hip.

National guidelines recommend that people exercise at least 30 minutes a day on most days of the week to maintain optimum health. But few people achieve that goal, citing lack of time as the biggest obstacle. Researchers say these results may help motivate people to fit in even a little exercise here and there to benefit their health.

In the study, published in the Journal of Epidemiology and Community Health, researchers invited 106 healthy but sedentary civil servants to take part in an exercise program for 12 weeks. About a third were told to briskly walk for 30 minutes, five days a week. Another third were told to briskly walk for 30 minutes a day, three days a week; the remaining third were told not to change their sedentary lifestyle at all.

The participants wore pedometers to monitor their walking, and researchers measured their blood pressure, blood cholesterol, weight, hip and waist size, and overall fitness before and after the study. The results showed systolic (the top number) blood pressure dropped - and waist and hip measurements shrunk significantly - in both the three-day-a-week and five-day-a-week exercise groups.

Systolic blood pressure dropped by 5 points among those who exercised three days a week and by 6 points among those who exercised five days a week. Waist and hip measurements fell by 2.6 centimeters and 2.4 centimeters respectively among the three-day-a-week exercisers and by 2.5 centimeters and 2.2 centimeters among the five-day-a-week exercise group. No changes were found in the sedentary group.

Source

Randomised controlled trial of home-based walking programmes at and below current recommended levels of exercise in sedentary adults

By Mark A Tully et al.

Abstract:

Objectives: To determine, using unsupervised walking programmes, the effects of exercise at a level lower than currently recommended to improve cardiovascular risk factors and functional capacity.

Design: 12 week randomised controlled trial.

Setting: Northern Ireland Civil Service; home-based walking.

Participants: 106 healthy, sedentary 40 to 61 year old adults of both sexes.

Interventions: Participants were randomly allocated to a walking programme (30 minutes brisk walking three days a week (n = 44) or five days a week (n = 42)) or a control group (n = 20). Participants could choose to walk in bouts of at least 10 minutes. They used pedometers to record numbers of steps taken. Intention to treat analysis of changes within groups was done using paired t tests; extent of change (baseline to 12 week measurements) was compared between groups using analysis of variance and Gabriel's post hoc test.

Main outcome measures: Blood pressure, serum lipids, body mass index, waist:hip ratio, and functional capacity (using a 10 m shuttle walk test).

Main results: 89% (93/106) completed the study. Systolic blood pressure and waist and hip circumferences fell significantly both in the three day group (5 mm Hg, 2.6 cm, and 2.4 cm, respectively) and in the five day group (6 mm Hg, 2.5 cm, and 2.2 cm) (p<0.05). Functional capacity increased in both groups (15%; 11%). Diastolic blood pressure fell in the five day group (3.4 mm Hg, p<0.05). No changes occurred in the control group.

Conclusions: This study provides evidence of benefit from exercising at a level below that currently recommended in healthy sedentary adults. Further studies are needed of potential longer term health benefits for a wider community from low levels of exercise.

Source

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Just some problems with the "Obesity" war:

1). It tries to impose behavior change on everybody -- when most of those targeted are not obese and hence have no reason to change their behaviour. It is a form of punishing the innocent and the guilty alike. (It is also typical of Leftist thinking: Scorning the individual and capable of dealing with large groups only).

2). The longevity research all leads to the conclusion that it is people of MIDDLING weight who live longest -- not slim people. So the "epidemic" of obesity is in fact largely an "epidemic" of living longer.

3). It is total calorie intake that makes you fat -- not where you get your calories. Policies that attack only the source of the calories (e.g. "junk food") without addressing total calorie intake are hence pissing into the wind. People involuntarily deprived of their preferred calorie intake from one source are highly likely to seek and find their calories elsewhere.

4). So-called junk food is perfectly nutritious. A big Mac meal comprises meat, bread, salad and potatoes -- which is a mainstream Western diet. If that is bad then we are all in big trouble.

5). Food warriors demonize salt and fat. But we need a daily salt intake to counter salt-loss through perspiration and the research shows that people on salt-restricted diets die SOONER. And Eskimos eat huge amounts of fat with no apparent ill-effects. And the average home-cooked roast dinner has LOTS of fat. Will we ban roast dinners?

6). The foods restricted are often no more calorific than those permitted -- such as milk and fruit-juice drinks.

7). Tendency to weight is mostly genetic and is therefore not readily susceptible to voluntary behaviour change.

8). And when are we going to ban cheese? Cheese is a concentrated calorie bomb and has lots of that wicked animal fat in it too. Wouldn't we all be better off without it? And what about butter and margarine? They are just about pure fat. Surely they should be treated as contraband in kids' lunchboxes! [/sarcasm].

Trans fats:

For one summary of the weak science behind the "trans-fat" hysteria, see here. Trans fats have only a temporary effect on blood chemistry and the evidence of lasting harm from them is dubious. By taking extreme groups in trans fats intake, some weak association with coronary heart disease has at times been shown in some sub-populations but extreme group studies are inherently at risk of confounding with other factors and are intrinsically of little interest to the average person.


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