Jan A. Witkowski

The Knockout Mouse Project

Mouse knockout technology provides a powerful means of elucidating gene function in vivo, and a publicly available genome-wide collection of mouse knockouts would be significantly enabling for biomedical discovery. To date, published knockouts exist for only about 10% of mouse genes. Furthermore, many of these are limited in utility because they have not been made or phenotyped in standardized ways, and many are not freely available to researchers. It is time to harness new technologies and efficiencies of production to mount a high-throughput international effort to produce and phenotype knockouts for all mouse genes, and place these resources into the public domain.Mouse knockout technology provides a powerful means of elucidating gene function in vivo, and a publicly available genome-wide collection of mouse knockouts would be significantly enabling for biomedical discovery. To date, published knockouts exist for only about 10% of mouse genes. Furthermore, many of these are limited in utility because they have not been made or phenotyped in standardized ways, and many are not freely available to researchers. It is time to harness new technologies and efficiencies of production to mount a high-throughput international effort to produce and phenotype knockouts for all mouse genes, and place these resources into the public domain.

Tackling antibiotic resistance

The development and spread of antibiotic resistance in bacteria is a universal threat to both humans and animals that is generally not preventable but can nevertheless be controlled, and it must be tackled in the most effective ways possible. To explore how the problem of antibiotic resistance might best be addressed, a group of 30 scientists from academia and industry gathered at the Banbury Conference Centre in Cold Spring Harbor, New York, USA, from 16 to 18 May 2011. From these discussions there emerged a priority list of steps that need to be taken to resolve this global crisis.

Current challenges in de novo plant genome sequencing and assembly

Genome sequencing is now affordable, but assembling plant genomes de novo remains challenging. We assess the state of the art of assembly and review the best practices for the community.

Influence of serum on attachment of tissue cells to glass surfaces

Abstract In serum-free medium, human diploid cells (MRC-5) spread more rapidly on glass surfaces than when serum is present, and the morphology of the cells throughout spreading is affected by the presence or absence of serum. It is suggested that a possible role of serum in tissue culture media is to modify either the cell or glass surfaces so that the cell is able to overcome forces that arise between cell and glass from surface charge effects.

Stages of spreading of human diploid cells on glass surfaces

Abstract Interference contrast and scanning electron microscopy have been used to study the spreading of the human diploid cell MRC-5 on glass. After trypsinization the cells were rounded-up and had a folded surface. Possible functions for these surface folds are discussed and related to the microvilli present on other cells. Microextensions developed very early after attachment to the glass surface and appeared to guide the spreading cytoplasm. During spreading, two intermediate cell shapes could be recognised before the fully spread fibroblast form was achieved. The rate at which the cells spread was estimated by measuring the proportions of these cell forms present.

Alexis Carrel and the mysticism of tissue culture.

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Redefining Genomic Privacy: Trust and Empowerment

Current models of protecting human subjects create a zero-sum game of privacy versus data utility. We propose shifting the paradigm to techniques that facilitate trust between researchers and participants.

DISEASED MUSCLE CELLS IN CULTURE

(1) Cultures of differentiated muscle cells have been grown from diseased human, mouse and chick skeletal muscle, and from cardiac muscle of the myopathic hamster.

Reduced adhesiveness between skin fibroblasts from patients with Duchenne muscular dystrophy

The intercellular adhesiveness of skin fibroblasts from patients with Duchenne muscular dystrophy and normal controls has been measured by determining the collision efficencies of cells using the couette viscometer. The collision efficencies for dystrophic cells were significantly lower that those for normal cells (0.01 greater than P greater than 0.005), indicating that dystrophic cells are less adhesive than normal cells.

Growth of diseased human muscle in combined cultures with normal mouse embryonic spinal cord

Normal and diseased human muscle cells have been grown in combined cultures with 12-14 day embryonic mouse spinal cord explants. Nerve endings on myotubes were found by light and scanning electron microscopy, and motor end-plates were identified by a histochemical reaction for acetylcholinesterase. Contracting myotubes, never observed in cultures of human muscle alone, were found in a culture from normal muscle. Histochemical studies demonstrated the presence of strongly and weakly reacting myotubes for both ATPase pH 9.4 and NADH-TR, but could not be related to the development of fibre types. No differences in morphology or histochemical reactions were found between normal and diseased muscle cells in these combined cultures.