Preface

The human microbiome is a collection of all microbiota that live in the human body: in the oral cavity and gastrointestinal tract, on the upper respiratory tract, in the urinary and genital tracts, in biological media (saliva, sputum, bile, feces, urine, seminal fluid, etc.). Humans are colonized by many microorganisms because the term «human microbiome» is sometimes used to refer to the collective genomes of all resident microorganisms including bacteria, archaea, fungi, protists, and viruses. The term «human microbiota» is used more often in scientific research when referring to microorganisms that do not cause diseases under normal conditions (non-pathogenic). Some micro-organisms that colonize humans are commensal, meaning they co-exist without harming humans; others have a mutualistic relationship with their human hosts.

Interest in the role of the human microbiome is extremely high, and for a long time, it was limited by the difficulties of cultivating numerous types of microorganisms that are part of the community. Modern laboratory technologies have made it possible to fully assess not only the taxonomic composition of microbial communities but also to gain new knowledge about the functional characteristics of the relationship between the microbiota and the human body.

This book presents data from recent years confirming the huge role that the microbiome plays in the human body. The results of scientific research using state-of-the-art technologies allowed us to establish that not only normal taxonomic diversity is important for human health, but also adequate functional activity of the microbiota. The book provides data on the features of changes in the microbiota in a number of problematic diseases and discusses hypotheses about cause-and-effect relationships in the microbiome-metabolome system.

In different chapters of the book, the results of fundamental and clinical research concerning the features of the microbiome in inflammatory, critical state, other pathological conditions, and diseases (stroke, cancer, autism, allergy, psoriasis, colitis, liver diseases, etc.) are presented; much attention is paid to the interaction of the microbiota and its metabolites with drugs and natural products. The conceptual data synthesis can be a basis for the development of new approaches to treatment when one of the important therapeutic targets will be the microbiota and its key metabolites.

The problem of the human microbiome is huge and immeasurable, it goes far beyond microbiology and includes almost all of medicine. Experience shows that young scientists and doctors actively participate in scientific research, feeling the prospects of this direction for solving problems of difficult-to-treat diseases. We would like to sincerely thank the authors for the pleasure of working on this book and express the hope that it will be interesting and useful to our dear readers.

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Section 1

Microbiome Research

Technologies

Section 1
