摘要:
Mass spectrometry techniques for determining the status of sepsis in an individual are provided. A biomarker profile resolved from a biological sample, taken from the individual, using a mass spectrometry technique is compared to a reference biomarker profile. A single such comparison classifies the individual as belonging to or not belonging to a reference population. The individual's biomarker profile and the reference biomarker profile comprise a plurality of ions each having a mass-to-charge ratio of about 100 Daltons to about 1000 Daltons. The plurality of ions can be detected by electrospray ionization mass spectrometry in positive mode. The comparison uses a decision rule, such as a classification tree, that determines the status of sepsis in the individual without requiring knowledge of the identity of the biomarkers in the biomarker profile from the individual and without requiring knowledge of the identity of the biomarkers in the reference biomarker profile.
摘要:
Mass spectrometry techniques for determining the status of sepsis in an individual are provided. A biomarker profile resolved from a biological sample, taken from the individual, using a mass spectrometry technique is compared to a reference biomarker profile. A single such comparison classifies the individual as belonging to or not belonging to a reference population. The individual's biomarker profile and the reference biomarker profile comprise a plurality of ions each having a mass-to-charge ratio of about 100 Daltons to about 1000 Daltons. The plurality of ions can be detected by electrospray ionization mass spectrometry in positive mode. The comparison uses a decision rule, such as a classification tree, that determines the status of sepsis in the individual without requiring knowledge of the identity of the biomarkers in the biomarker profile from the individual and without requiring knowledge of the identity of the biomarkers in the reference biomarker profile.
摘要:
Mass spectrometry techniques for determining the status of sepsis in an individual are provided. A biomarker profile resolved from a biological sample, taken from the individual, using a mass spectrometry technique is compared to a reference biomarker profile. A single such comparison classifies the individual as belonging to or not belonging to a reference population. The individual's biomarker profile and the reference biomarker profile comprise a plurality of ions each having a mass-to-charge ratio of about 100 Daltons to about 1000 Daltons. The plurality of ions can be detected by electrospray ionization mass spectrometry in positive mode. The comparison uses a decision rule, such as a classification tree, that determines the status of sepsis in the individual without requiring knowledge of the identity of the biomarkers in the biomarker profile from the individual and without requiring knowledge of the identity of the biomarkers in the reference biomarker profile.
摘要:
The early prediction or diagnosis of sepsis advantageously allows for clinical intervention before the disease rapidly progresses beyond initial stages to the more severe stages, such as severe sepsis or septic shock, which are associated with high mortality. Early prediction or diagnosis is accomplished by comparing an individual's profile of biomarker expression to profiles obtained from one or more control, or reference, populations, which may include a population that develops sepsis. Recognition of features in the individual's biomarker profile that are characteristic of the onset of sepsis allows a clinician to diagnose the onset of sepsis from a bodily fluid isolated from the individual at a single point in time. The necessity of monitoring the patient over a period of time is, therefore, avoided, advantageously allowing clinical intervention before the onset of serious symptoms of sepsis. Further, because the biomarker expression is assayed for its profile, identification of the particular biomarkers is unnecessary. The comparison of an individual's biomarker profile to biomarker profiles of appropriate reference populations likewise can be used to diagnose SIRS in the individual.
摘要:
An array of micro-chambers 220) with individual ion sensitive field effect transistors (ISFETs) (300) disposed therein for monitoring single cell activity in the microarray to determine the presence or absence of microorganisms in a sample (390). In addition to the presence or absence of a single cell, certain further embodiments contemplate monitoring cell behavior. Cell behavior includes the entire range of cell activity as well as cell response to changes in environmental conditions of changes in response due to the addition of sample constituents.
摘要:
Presented herein are methods and compositions for generating sequence-specific, secondary amplification products during Loop-mediated Isothermal Amplification (LAMP). Conventional LAMP produces a preponderance of high molecular weight DNA structures concatenated into self-complementary hairpins, which are not amenable to detection by routine probe-based hybridization methods, making multiplex detection of two or more targets or sequence variants in closed-tube formats extremely difficult. Provided herein, for example, are methods for generating secondary LAMP products bearing a fragment of the original target sequence embedded within low-molecular weight products that are devoid of competitive hairpin structures, the lack of which enhances probe-based detection of target sequences. These secondary products can, for example, be produced in real-time, during the LAMP process, and can provide the option of detecting multiple target sequences within a single tube using, e.g., a homogenous, real-time fluorescence format.
摘要:
Single-stranded signal primers are modified by linkage to two dyes which form a donor/acceptor dye pair. The two dyes are positioned in sufficiently close spatial proximity on the signal primer that the fluorescence of the first dye is quenched by the second dye. The signal primer may further comprise a restriction endonuclease recognition site (RERS) between the two dyes. As the signal primer is initially single-stranded and remains single-stranded in the absence of target, the restriction endonuclease recognition site is not cleavable or nickable by the restriction endonuclease. In the presence of target, however, signal primer and the restriction endonuclease recognition site are rendered double-stranded and cleavable or nickable by the restriction endonuclease. Cleavage or nicking separates the two dyes and a change in fluorescence due to decreased quenching is detected as an indication of the presence of the target sequence or of target sequence amplification.
摘要:
Methods employing internal oligonucleotide standards in isothermal nucleic acid amplification reactions to determine the efficacy of the amplification reaction and to quantify pre-amplification target levels.
摘要:
Methods for multiplex amplification of target nucleic acid sequences using a single pair of primers. Defined sequences are appended to the ends of multiple target sequences as part of the amplification reaction so that no steps in addition to amplification are required. The target sequences with the appended defined sequences need not be isolated prior to amplification. In one embodiment for coamplification of two target sequences, a sequence corresponding to a terminal segment of the first target sequence is appended to one end of the second target sequence and a sequence corresponding to a terminal segment of the second target sequence is appended to one end of the first target sequence. Amplification of the two targets then requires only a single pair of primers. Alternatively, a single defined sequence may be appended to the 5' and 3' ends of any number of selected targets. All such modified target sequences may then be amplified using a single pair of primers which hybridize to the defined end-sequences.
摘要:
The invention employs an unlabeled signal primer comprising a 5′ adapter sequence for detection of variations in nucleic acid target sequences. The detection system further comprises a reporter probe, the 3′ end of which hybridizes to the complement of the 5′ adapter sequence of the signal primer to produce a 5′ overhang. Polymerase is used to fill in the overhang and synthesize the complement of the 5′ overhang of the reporter probe. Synthesis of the reporter probe complement is detected, either directly or indirectly, as an indication of the presence of the target.