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B Maloney

Publications and source records attributed to B Maloney.

7 recordsLinked to original sources

Construction of recombinant avian infectious laryngotracheitis virus expressing the beta-galactosidase gene and DNA sequencing of the insertion region.

Avian infectious laryngotracheitis virus (ILTV), a herpesvirus, is a highly contagious pathogen that causes an upper respiratory tract infection in chickens. It is one of the major problems in the poultry industry worldwide. Current vaccines are not satisfactory due to the induction of latent infection. Here we describe a system for the construction of recombinant ILTV. A 4-kbp ILTV EcoRI DNA fragment was cloned into plasmid pUC13 and sequenced. Computer prediction revealed two potential open reading frames with 216 and 259 amino acid residues, respectively. The 259-residue polypeptide was serine-rich. The beta-galactosidase (beta-gal) gene of E. coli was cloned into the XhoI/Bg/II site of this DNA fragment, integrated into the ILTV genome via homologous recombination, expressed under the control of the immediate-early cytomegalovirus promoter, and caused the formation of blue plaques in the presence of X-gal. The insertion of a foreign gene into the ILTV genome and the successful expression of the incorporated gene demonstrated the potential for the construction of attenuated recombinant ILTV vaccines and the development of ILTV as vectors for polyvalent vaccines against avian upper respiratory tract infections.

Amino Acid Sequence↗

Demonstration of human T lymphotropic virus type I (HTLV-I)-specific T cell responses from seronegative and polymerase chain reaction-negative persons exposed to HTLV-I.

Human T lymphotropic virus type I (HTLV-I) is a human retrovirus etiologically linked to adult T cell leukemia and the progressive chronic neurologic disease HTLV-I-associated myelopathy/tropical spastic paraparesis. Described is a method that measures the production of interleukin-2 from HTLV-I synthetic peptide-stimulated peripheral blood lymphocytes (PBL) of HTLV-I-infected persons. The peptides correspond to immunogenic regions of the HTLV-I Env and Tax proteins. Significantly, this assay demonstrated T cell responses to these HTLV-I peptides from coded PBL samples in 7 of 19 HTLV-I-seronegative polymerase chain reaction-negative persons known to have been exposed to HTLV-I but in none of 16 matched controls without risk factors for exposure (P = .007). The implications of this finding are discussed.

Adult↗

Assembly pathway of avian infectious laryngotracheitis virus.

Infectious laryngotracheitis virus (ILTV) is the causative agent of a highly contagious upper respiratory tract infection in chickens. At present, ILTV vaccines are not satisfactory because of development of a latent carrier status in vaccinated birds. Development of recombinant virus vaccines has been hampered by the limited information available on the molecular level and organization of this virus. We isolated 3 assembly intermediates, designated A, B, and C from ILTV-infected cells. Analysis of [3H]thymidine-and [35S]methionine-labeled particles, and electron microscopic studies indicated that particle A was the empty capsid, particle B was the procapsid containing scaffolding protein, and particle C was the DNA-filled capsid. The ILTV procapsids could only be found in the nucleus, which indicated that procapsids could not translocate through the nuclear membrane until they packaged the DNA. The DNA-filled capsids migrated through the nuclear membrane and obtained an envelope from the inner membrane of the nucleus. The enveloped particles then migrated through the lumen of the endoplasmic reticulum into vacuoles in the cytoplasm. Infective virions were isolated from within the infected cells, indicating that budding through the cytoplasmic membrane is not a necessary step in ILTV maturation. Abundant arrays composed of tubules about 45 to 50 nm wide were found in the cytoplasm of chicken embryonic liver cells about 30 to 38 hours after infection. Comparison of the assembly intermediates and the DNA packaging pathway of ILTV with that of bacteriophage pi 29 indicates that similarity exists.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

Recurrent unilateral lung disease.

A 25-year-old patient, with multiple pulmonary metastases from osteogenic sarcoma who two years ago developed respiratory failure with unilateral left lung involvement and was successfully treated with independent lung ventilation, was readmitted to an ICU with recurrent unilateral lung disease. Conventional therapy failed to reverse the respiratory failure; independent ventilation temporarily improved the patient's oxygenation. At autopsy, different involvement of the two lungs by the tumor was evident so that blood flow of the right lung and lymphatic flow of the left lung were impaired. When respiratory failure unresponsive to conventional therapy develops, anatomical abnormalities should be considered.

Adult↗