David Jacob Stephens

US Patent:

6403306, Jun 11, 2002

Filed:

Sep 23, 1997

Appl. No.:

08/936107

Inventors:

David S. Stephens - Stone Mountain GA
John S. Swartley - Westport CT

Assignee:

Emory University - Atlanta GA

International Classification:

C12Q 168

US Classification:

435 6, 536 237, 536 243, 536 2432, 4353201, 435975

Abstract:

The present invention is based on the discovery of meningococcal isolates having genetic markers of a particular serogroup but expressing a capsular polysaccharide of a different serogroup. These isolates and prototype serogroup A, B, C, Y and W-135 strains were used to define the capsular biosynthetic operon of the major meningococcal serogroups and to show that capsule switching occurs as a result of allelic exchange of, for example, the polysialyl-transferase gene. Findings of capsule switching in vivo indicate that closely related virulent meningococcal clones may not be recognized by traditional serogroup-based surveillance and can escape vaccine-induced or natural protective immunity by capsule switching. The invention provides recombinant meningococcal strains, recombinant DNA constructs and immunological preparations useful as diagnostic probes for detection and diagnosis of meningococcal diseases, screening for specific meningococcal serogroups and broad based immunizations with multivalent capsular polysaccharide conjugate vaccines.

US Patent:

6472518, Oct 29, 2002

Filed:

Aug 17, 1999

Appl. No.:

09/284926

Inventors:

Efrain M. Ribot - Atlanta GA
David S. Stephens - Stone Mountain GA
Nigel Raymond - Wellington, NZ
Frederick D. Quinn - Avondale Estates GA

Assignee:

Centers for Disease Control and Prevention, as represented by the Secretary, Department of Health and Human Services - Atlanta GA

International Classification:

C07H 2104

US Classification:

536 237, 536 2432, 536 2433, 536 241, 4242501, 435243, 4352523, 4353201, 435 691, 435 693

Abstract:

Genes isolated from , as well as isolated nucleic acids, probes, expression cassettes, polypeptides, antibodies, immunogenic compositions, antisense nucleic acids, amplification mixtures, and new invasion deficient swains of are provided Methods of detecting and nucleic acids, and methods of inhibiting the invasion of mammalian cells by are also provided.

US Patent:

7348161, Mar 25, 2008

Filed:

Mar 15, 2002

Appl. No.:

10/472801

Inventors:

Kathryn Gay - Atlanta GA, US
David S. Stephens - Stone Mountain GA, US

Assignee:

Emory University - Atlanta GA

International Classification:

C12Q 1/37
C12Q 1/14
C07K 14/325
C12N 1/20

US Classification:

435 237, 530350, 43525233, 435 72, 435 32

Abstract:

Macrolide resistance associated with macrolide efflux (mef) in has been defined with respect to the genetic structure and dissemination of a novel mefE-containing chromosomal insertion element. The mefE gene is found on the 5′-end of a 5. 5 kb or 5. 4 kb insertion designated mega (acrolide fflux enetic ssembly) found in at least four distinct sites of the pneumococcal genome. The element is transformable and confers macrolide resistance to susceptible. The first two open reading frames (ORFs) of the element form an operon composed of mefE and a predicted ATP-binding cassette homologous to msrA. Convergent to this efflux operon are three ORFs with homology to stress response genes of Tn5252. Mega is related to mefA-containing element Tn1207. 1. Macrolide resistance due to mega has been rapidly increased by clonal expansion of bacteria containing it and horizontally by transformation of previously sensitive bacteria.

US Patent:

7497819, Mar 3, 2009

Filed:

Mar 6, 2007

Appl. No.:

11/682681

Inventors:

Jack C. White - Alpharetta GA, US
David Wesley Stephens - Cornelia GA, US
Amit Prakash Govil - Gainesville FL, US
Joshua J. Bergman - Myrtle Point OR, US
Nathan Christopher Griffith - Lawrenceville GA, US
Kyle Kevin Millage - Flemington NJ, US

Assignee:

Theragenics Corporation - Buford GA

International Classification:

A61N 5/00

US Classification:

600 3

Abstract:

A brachytherapy device for the provision of brachytherapy is disclosed. The brachytherapy device has at least one source lumen located outside a movable surface of the device. The source lumen may be secured to the movable outer surface in a manner whereby relative movement of the source lumen relative to the movable outer surface is permitted. The brachytherapy device is inserted into a body cavity. After insertion, the movable surface is moved to position the at least one source lumen closer to the tissue boundary of the cavity. One or more sources of radiation are then placed within the at least one source lumen to provide a customizable treatment. Also disclosed are methods for providing brachytherapy via body cavities.

US Patent:

7497820, Mar 3, 2009

Filed:

Mar 19, 2007

Appl. No.:

11/688033

Inventors:

Jack C. White - Alpharetta GA, US
David Wesley Stephens - Cornelia GA, US
Amit Prakash Govil - Gainesville FL, US
Joshua J. Bergman - Myrtle Point OR, US
Nathan Christopher Griffith - Lawrenceville GA, US
Kyle Kevin Millage - Flemington NJ, US

Assignee:

Theragenics Corporation - Buford GA

International Classification:

A61N 5/00

US Classification:

600 3

Abstract:

A brachytherapy device for the provision of brachytherapy is disclosed. The brachytherapy device has at least one source lumen located outside a movable surface of the device. The source lumen may be secured to the movable outer surface in a manner whereby relative movement of the source lumen relative to the movable outer surface is permitted. The brachytherapy device is inserted into a body cavity. After insertion, the movable surface is moved to position the at least one source lumen closer to the tissue boundary of the cavity. One or more sources of radiation are then placed within the at least one source lumen to provide a customizable treatment. Also disclosed are methods for providing brachytherapy via body cavities.

US Patent:

7662082, Feb 16, 2010

Filed:

Nov 4, 2005

Appl. No.:

11/266994

Inventors:

Jack C. White - Alpharetta GA, US
David Wesley Stephens - Cornelia GA, US
Amit Prakash Govil - Gainesville FL, US
Joshua J. Bergman - Myrtle Point OR, US
Nathan Christopher Griffith - Lawrenceville GA, US
Kyle Kevin Millage - Flemington NJ, US

Assignee:

Theragenics Corporation - Buford GA

International Classification:

A61N 5/00

US Classification:

600 3

Abstract:

A brachytherapy device for the provision of brachytherapy is disclosed. The brachytherapy device has at least one source lumen located outside a movable surface of the device. The source lumen may be secured to the movable outer surface in a manner whereby relative movement of the source lumen relative to the movable outer surface is permitted. The brachytherapy device is inserted into a body cavity. After insertion, the movable surface is moved to position the at least one source lumen closer to the tissue boundary of the cavity. One or more sources of radiation are then placed within the at least one source lumen to provide a customizable treatment. Also disclosed are methods for providing brachytherapy via body cavities.

US Patent:

7807181, Oct 5, 2010

Filed:

Mar 20, 2003

Appl. No.:

10/508309

Inventors:

David S. Stephens - Stone Mountain GA, US
Yih-Ling Tzeng - Atlanta GA, US
Susu Zughaier - Atlanta GA, US
Shanta Zimmer - Atlanta GA, US

Assignee:

Emory University - Atlanta GA

International Classification:

A61K 39/02
A61K 39/095
A61K 39/38
A01N 43/04
C07H 1/00

US Classification:

4242341, 4241841, 4242501, 4242491, 514 23, 5361231

Abstract:

Provided herein are mutant strains of which produce Kdo-free lipid A as well as the Kdo-free lipid A molecules and immunogenic compositions containing such Kdo-free lipid A molecules from a strain containing a genetically stable mutation which inactivates a gene selected from the group consisting of genes encoding arabinose-5-phosphate isomerase, CMP-Kdo synthetase and CMP-Kdo transferase. NMB206 is a specifically exemplified strain which harbors a stable insertion mutation in the gene (kpsF) encoding A5P isomerase; strain NMB-249 is a specifically exemplified strain with a stable insertion mutation in the gene (kdtA) encoding CMP-Kdo synthetase, and strain NMB259 is specifically exemplified strain with a stable insertion mutation in the gene (kdsB) encoding CMP-Kdo transferase. Also provided by the present invention are methods for the production of Lipid A flee of 3-keto-3-deoxyoctanoic acid using these genetically stable mutants. Also describes is pYT250, a plasmid functional in neisseriae and in enterics such as.

US Patent:

8398534, Mar 19, 2013

Filed:

Jan 22, 2010

Appl. No.:

12/692289

Inventors:

Jack C. White - Alpharetta GA, US
David Wesley Stephens - Cornelia GA, US
Amit Prakash Govil - Gainesville FL, US
Joshua J. Bergman - Myrtle Point OR, US
Nathan Christopher Griffith - Lawrenceville GA, US
Kyle Kevin Millage - Flemington NJ, US

Assignee:

Theragenics Corporation - Buford GA

International Classification:

A61N 5/00

US Classification:

600 3

Abstract:

A brachytherapy device including an elongate member comprising a proximal portion and a distal portion. The device also includes a movable surface portion surrounding at least the distal portion of the elongate member and a plurality of source lumen tubes defining respective source lumens, the source lumen tubes being located around the elongate member, distal ends of the source lumen tubes coupled to the distal portion of the elongate member, the source lumen tubes extending a sufficient distance in a proximal direction such that the source lumen tubes extend outside a body when distal portions of the source lumen tubes are positioned in a body cavity for brachytherapy. The device also has structure coupled to the distal ends of the source lumen tubes for positioning the distal portions of the source lumen tubes at different distances from the elongate member for brachytherapy by exerting a force in a proximal direction on the distal ends of the source lumen tubes, the structure including an actuator for actuating the structure, at least a portion of the actuator being located outside the body when the distal portions of the source lumen tubes are positioned in a body cavity for brachytherapy. The device also includes a ring, tube or manifold securing a portion of the source lumen tubes proximal to the distal portion around the elongate member and a source of radiation suitable for insertion into the source lumens.