Цитата:
Сообщение от Dr_StaSiL
Да, речь идет в том числе и о терминологии. Не о диагнозе! Ну нет такого диагноза...НЕТ его. Нет в МКБ. Ни в историях, ни в амбулаторках быть не должно. Когда кишечник (в данном контексте), влагалище, другая локализация заселяется вдруг чужеродной для них микрофлорой....или меняется соотношение микроорганизмов....Появляется ОН...ДИСБАКТЕРИОЗ. Или не так?
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Дискутировать по этому вопросу скучно, ибо очевиден недостаток фактических знаний по проблеме. Попробую восполнить цитатами из
Handbook of prebiotics / Eds. Glenn R. Gibson and Marcel Roberfroid. CRC Press, 2008
Цитата:
The gut houses an enormous microbial community with total
estimates in the region of 10^14 microorganisms. The distal large intestine is the
area of highest colonization with more than 500 different culturable species
and up to 100 billion microbial inhabitants.3 The total number of microorganisms
present in the gastrointestinal tract varies according to location. For example
stomach contents (per gram) could be less than
103 cfu, reaching 10^4–10^7 in the small intestine and 10^10–10^12 per gram in the
colon where the microbial numbersar e highest.4 The end product of digestion
(feces) is approximately 60% composed of bacteria.5 The whole microbiome
is thought to contain approximately 100 times the number of genes in the
human genome.6 There are four main microhabitats in the gastrointestinal
tract; the epithelial surface, the mucuslayer that overlays the epithelium, the
crypts of the ileum, cecum and colon, and the intestinal lumen.
Composition of Microflora
The composition of the gut microflora has previously been elucidated
through phenotypic techniques.7 and more recently using culture independent
approaches that allow classification of bacteria based upon phylogenetic
comparison of 16S rRNA sequences. This information has provided a recent
estimate of the diversity of the gut microbiota. Based on the analysis of 16S
rRNA gene sequences it was found out that eight of the 55 known bacterial
kingdoms are present in the gut indicating a huge diversity at the
strain and subspecies levels. In the Genbank sequence accession database
there are more than 200,000 16S rRNA sequence deposits, however only 1822
are considered to be of human intestinal origin.6 The numerically dominant
divisions (super kingdoms) within the human intestine are the Cytophaga-
Flavobacterium-bacteroides (including genus Bacteroides) and the Firmicutes
(including genera Eubacterium and Clostridium) and both comprise approximately
30% of the total bacteria in mucusand feces.6 Anaerobic organisms
dominate the gut by 100- to 1000-fold greater than aerobes.8 Other dominant
anaerobic genera include peptococci, peptostreptococci, bifidobacteria,
and ruminococci. Subdominant aerobic (or facultatively anaerobic) genera
include escherichia, enterobacter, enterococci, klebsiella, lactobacilli, and proteus
including others.8 Molecular analysis has shown that the aerobic species
present reach relatively high cell densities and metabolic activity in the human
cecum, in fact 50% of total bacterial ribosomal RNA was found to correspond
to these species in this region of the gut. This is in contract to feces
in which only 7% of the total bacterial ribosomal RNA from these species is
found.9
Factors Affecting Composition of the Microflora
Although the major dominant bacterial groupshave been described, there is
considerable species variation between individuals. For example, all humans
have many species within each genus. The foremost species within that genus
will differ considerably between individuals.40 In a healthy gut, there is a balance
between potentially harmful and beneficial bacteria. Probably the most
important factors in determining the initial colonization pattern are the type
of delivery at birth (either vaginal or caesarean section) and the initial diet
(whether the baby isfed mother’smilk or infant formula). The microbiota in
a newborn changes rapidly during the first few weeks and during weaning.3
Other important factors include the environment, age, gender, and diet. Variations in
microflora composition have been found between infants born in
different countries and raised with different diets, also even between hospital
wards.41−44
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Таким образом, имеем
- микробный состав кишечника разнообразен и включает сотни и тысячи видов микробов;
- микробный состав фекалий не соответствует микробиоценозу кишечника;
- сложно найти двух людей с одинаковым микробиоценозом кишечника;
- микробиоценоз кишечника динамически изменяется.
Отсюда следуют простые выводы:
если Вы хотите доказать возникновение "дисбактериоза" под воздействием чего-либо, то необходимо 1) исследовать микробный состав кишечника (не фекалий!) до какого-либо воздействия, 2) осуществить воздействие, 3) повторно исследовать микробиоценоз кишечника, 4) доказать, что нарушен микробный баланс в пользу преобладания потенциально опасных микробов (именно "потенциально", потому что если будут преобладать патогенные - то разовьется характерное заболевание).
Видели ли Вы где-либо опубликованные исследования, выполненные по такому дизайну?