The invention concerns methods for mapping microbial niches and their uses.

Detecting single bacterial cells in a sample includes collecting, from a sample provided to an imaging apparatus, a multiplicity of images of the sample over a length of time; assessing a trajectory of each bacterial cell in the sample; and assessing, based on the trajectory of each bacterial cell in the sample, a number of bacterial cell divisions that occur in the sample during the length of time.

Detecting single bacterial cells in a sample includes collecting, from a sample provided to an imaging apparatus, a multiplicity of images of the sample over a length of time; assessing a trajectory of each bacterial cell in the sample; and assessing, based on the trajectory of each bacterial cell in the sample, a number of bacterial cell divisions that occur in the sample during the length of time.

The present disclosure relates to methods of collecting and testing bacteria containing samples from within the gastrointestinal (GI) tract of a subject. The methods may include disposing an ingestible device in the GI tract, collecting a bacteria-containing sample from the GI tract, selectively lysing eukaryotic cells in the sample by combining the sample with a dried reagent, exposing bacteria in the sample to resazurin in the ingestible device to produce resorufin, emitting light from the ingestible device, the emitted light being filtered through an optical filter to control for scatter so that the light interacts with the resorufin to produce fluorescence, and measuring a total fluorescence from the resorufin; or a rate of change of fluorescence from the resorufin as a function of time within the GI tract of the subject; and correlating the measured parameter to a number of viable bacterial cells in the sample.

The present disclosure relates to methods of collecting and testing bacteria containing samples from within the gastrointestinal (GI) tract of a subject. The methods may include disposing an ingestible device in the GI tract, collecting a bacteria-containing sample from the GI tract, selectively lysing eukaryotic cells in the sample by combining the sample with a dried reagent, exposing bacteria in the sample to resazurin in the ingestible device to produce resorufin, emitting light from the ingestible device, the emitted light being filtered through an optical filter to control for scatter so that the light interacts with the resorufin to produce fluorescence, and measuring a total fluorescence from the resorufin; or a rate of change of fluorescence from the resorufin as a function of time within the GI tract of the subject; and correlating the measured parameter to a number of viable bacterial cells in the sample.

A microorganism test method includes: covering, with a hydrophobic capping solvent, a sample containing a specimen and a liquid culture medium, within a region in a vicinity of a sensor configured to detect a microorganism contained in the specimen; and calculating, based on an output from the sensor, information indicating a degree of growth of the microorganism contained in the specimen. For example, an analysis unit drives an array sensor in which many resonators are arranged in a matrix pattern, stores a resonance frequency of a resonator which is acquired at the time of starting the measurement as an initial frequency, and calculates a difference (frequency shift) between the initial frequency and a resonance frequency of the resonator which is measured at predetermined time intervals as information indicating a degree of growth of the microorganism contained in the specimen.

The present invention provides, in order to prepare matured hepatocytes analogous in various points to primary hepatocytes, a method for preparing hepatocytes or cells that can be differentiated into hepatocytes from pluripotent stem cells, comprising the steps of: (1) culturing the pluripotent stem cells in a medium containing an activator of an activin receptor-like kinase-4,7; (2) culturing the cells obtained in the step (1) in a medium containing a bone morphogenetic factor and a fibroblast growth factor; (3) culturing the cells obtained in the step (2) in a medium containing an activator of a hepatocyte growth factor receptor and an activator of an oncostatin M receptor; and (4) culturing the cells obtained in the step (3) to obtain hepatocytes or cells that can be differentiated into hepatocytes, wherein in at least one of the steps (2), (3) and (4), cells are cultured on a high-density collagen gel membrane.

Devices, systems, and methods described herein relate to determining a concentration of a species of interest in a sample by using a spectrometer. For example, a concentration of a species of interest may be determined by passing a first feed of a sample with a species of interest through a flow-through variable pathlength spectrophotometer and reading a first absorbance value. A change in the concentration of the species of interest may be effected in the sample, and a second feed of the sample may be passed through a flow through variable pathlength spectrophotometer. A second absorbance value may be read. The difference between the first absorbance value and the second absorbance value may be used to determine the concentration of the species of interest.

Devices, systems, and methods described herein relate to determining a concentration of a species of interest in a sample by using a spectrometer. For example, a concentration of a species of interest may be determined by passing a first feed of a sample with a species of interest through a flow-through variable pathlength spectrophotometer and reading a first absorbance value. A change in the concentration of the species of interest may be effected in the sample, and a second feed of the sample may be passed through a flow through variable pathlength spectrophotometer. A second absorbance value may be read. The difference between the first absorbance value and the second absorbance value may be used to determine the concentration of the species of interest.

Disclosed is a method for detection and/or quantification of microorganism in a liquid sample, in particular in a water sample, the method comprising the steps of: (a) distributing the liquid sample into a number of different discrete volume portions in a linear distribution pattern, or diluting the liquid sample into a number of dilution samples by a dilution factor of a linear distribution pattern; (b) allowing the microorganism to grow; and (c) applying the Most Probable Number method to the linearly distributed volume portions or the linearly diluted dilution samples to detect and/or quantify the microorganism. The invention also discloses a sample holder for detection and/or quantification of microorganism in a liquid sample, wherein the sample holder is structured to hold the liquid sample in a number of different compartments, wherein the different compartments respectively define a linear volume distribution.