Leland Stanford Junior University

Gilbert Chu

Chun J Tsai

Matthew William Kanan

Thomas Richard Veltman

Robert Tibshirani

Ron Davis

Virginia Goss Tusher

Douglas Vollrath

Jean Tang

Wan-Jen Hong

Seonhi Kim

Kerri Elyse Rieger

A method for measuring ammonia in a blood sample may involve positioning the blood sample in proximity with an ammonia gas sensor, generating a current with the ammonia gas sensor in response to ammonia gas released from the blood sample, and measuring the current generated by the ammonia gas sensor, using a current measurement member coupled with the ammonia gas sensor. A device for measuring an ammonia level in a blood sample may include a blood sample containment member, an ammonia gas sensor coupled with the blood sample containment member, and a current measurement member coupled with the ammonia gas sensor. The method and device may be used to measure an ammonia level in a blood sample as small as one drop of blood, or approximately 0.05 mL of blood.

Rapid small volume detection of blood ammonia

A mismatched end DNA ligase is provided, which ligates two single strands to each other at a high efficiency, even if the other two single strands are not compatible. In one embodiment, the polypeptides of the ligase are Ku, Cernunnos, and XRCC4/Ligase4 (XL). This association can ligate DNA ends with a 3' overhang to a recessed 5&#x2032; end, to a blunt end, or to a compatible end. In another embodiment, the proteins are Ku, Cernunnos, XRCC4/Ligase4 (XL) and DNA-PK.

Mismatched end DNA ligase

Methods are provided for determining whether a patient treated with an anti-proliferative agent is susceptible to toxicity. In practicing the subject methods, an expression profile for the transcriptional response to a therapy is obtained from the patient and compared to a reference profile to determine whether the patient is susceptible to toxicity. In addition, reagents and kits thereof that find use in practicing the subject methods are provided.

Methods and compositions for determining risk of treatment toxicity

Microarrays can measure the expression of thousands of genes and thus identify changes in expression between different biological states. Methods are needed to determine the significance of these changes, while accounting for the enormous number of genes. We describe a new method, Significance Analysis of Microarrays (SAM), that assigns a score to each gene based on the change in gene expression relative to the standard deviation of repeated measurements. For genes with scores greater than an adjustable threshold, SAM uses permutations of the repeated measurements to estimate the percentage of such genes identified by chance, the false discovery rate (FDR). When the transcriptional response of human cells to ionizing radiation was measured by microarrays, SAM identified 34 genes that changed at least 1.5-fold with an estimated FDR of 12%, compared to FDRs of 60% and 84% using conventional methods of analysis. Of the 34 genes, 19 were involved in cell cycle regulation, and 3 in apoptosis. Surprisingly, 4 nucleotide excision repair genes were induced, suggesting that this repair pathway for UV-damaged DNA might play a heretofore unrecognized role in repairing DNA damaged by ionizing radiation.

Significance analysis of microarrays

A gel electrophoresis method and apparatus is described in which the shape and orientation of the electric field is controlled by contour clamping. Electrodes are arranged around a closed contour. Two or more electrodes, the driving electrodes, are clamped at a potential difference .phi..sub.0 to establish the general orientation and strength of the electric field. The remaining electrodes are clamped to intermediate potentials to control the shape of the field established by the driving electrodes. The field is varied in accordance with the purpose of the electrophoresis, depending upon the size of the particles and the information to be determined concerning the particles.

Growing community of inventors

Palo Alto, CA, United States of America

Gilbert Chu