PubMed Health⌕ Search

Biomedical subjects

J F Rodriguez

Publications and source records attributed to J F Rodriguez.

43 records · Page 3Linked to original sources

Molecular cloning, encoding sequence, and expression of vaccinia virus nucleic acid-dependent nucleoside triphosphatase gene.

A rabbit poxvirus genomic library contained within the expression vector lambda gt11 was screened with polyclonal antiserum prepared against vaccinia virus nucleic acid-dependent nucleoside triphosphatase (NTPase)-I enzyme. Five positive phage clones containing from 0.72- to 2.5-kilobase-pair (kbp) inserts expressed a beta-galactosidase fusion protein that was reactive by immunoblotting with the NTPase-I antibody. Hybridization analysis allowed the location of this gene within the vaccinia HindIIID restriction fragment. From the known nucleotide sequence of the 16-kbp vaccinia HindIIID fragment, we identified a region that contains a 1896-base open reading frame coding for a 631-amino acid protein. Analysis of the complete sequence revealed a highly basic protein, with hydrophilic COOH and NH2 termini, various hydrophobic domains, and no significant homology to other known proteins. Translational studies demonstrate that NTPase-I belongs to a late class of viral genes. This protein is highly conserved among Orthopoxviruses.

Adenosine Triphosphate↗

Isolation and characterization of neutralizing monoclonal antibodies to vaccinia virus.

Cells producing neutralizing monoclonal antibodies (mAbs) to UV-inactivated vaccinia virus strain WR were derived by fusion of hyperimmunized mouse spleen cells with mouse myeloma cells. Three mAbs that reacted strongly with purified virus envelopes as determined by enzyme-linked immunosorbent assay were studied. The three mAbs recognized a 14,000-molecular-weight (14K) envelope protein of vaccinia virus and were shown to be immunoglobulin G2b (mAbC3 and mAbB11) and immunoglobulin M (mAbF11). By using ascites, one of the antibodies, mAbC3, neutralized (50%) virus infectivity with a titer of about 10(-4), whereas the others exhibited lower neutralization titers of 10(-2) to 10(-3). The binding of the mAbs to vaccinia virus did not alter virus attachment to cells. However, virus uncoating was extensively blocked by mAbC3, whereas mAbB11 and mAbF11 had little or no effect. The three mAbs recognized a similar 14K protein in cowpox, rabbitpox, and vaccinia Elstree strains, indicating a high degree of protein conservation among orthopoxviruses. Based on the binding of mAbs to V-8 protease cleavage products of the 14K protein, the extent of protein recognition for other poxviruses, and differences in the degree of virus neutralization and of virus uncoating into cells, we suggest that the three mAbs recognize different domains of vaccinia 14K viral envelope protein. Furthermore, our findings indicate that the 14K protein may play a role in virus penetration.

Antibodies, Monoclonal↗

Stabilization and polysaccharide storage in group A Streptococcus pyogenes.

Water-shock treatment of group A Streptococcus pyogenes released a mixture of nucleotide-like substances and small amounts of protein. The amount of protein was much less than found with osmotic shock of Gram-negative bacteria. In group A S. pyogenes the osmolytes released exhibited as much as a 6-fold change in respect to different growth phases. Osmolyte release was dependent on the stabilization agent used and independent of cellular metabolic activity. The released osmolytes were found to be required for optimal intracellular iodophilic polysaccharide (IPS) storage. Stabilization of washing solutions, and IPS storage medium with metabolically inert non-ionic organic compounds prevented osmolyte loss and enhanced IPS storage. Polyvinyl pyrrolidone and polyethyleneglycol (MW greater than 1000) exhibited the same protective effects as found with calf serum. Smaller non-ionic organic compounds provided similar protective action but the bacteria were more susceptible to osmotic stress.

Maltose↗

Factors affecting polysaccharide storage in group A Streptococcus pyogenes in non-proliferating cell suspensions.

Optimal conditions for intracellular polysaccharide (IPS) storage by non-proliferating suspensions of group A Streptococcus pyogenes are described. Concentrations of yeast extract and acid-hydrolysed casein which did not support measureable growth prevented bacterial death during storage. For optimal storage, high concentrations of maltose were required to antagonize the inhibitory effect of medium glucose released by intracellular amylomaltase activity. Stabilization of cell washing solutions with 0.5 M sucrose and the minimal storage medium with 8.0% w/v polyethylene glycol MW 6,000 was required for optimal culture viability and IPS storage. The stabilization effect prevented loss of small purine or pyrimidine-containing compounds required for IPS storage as indicated by culture water-shock treatment.

Culture Media↗

The three dose components of negative pion beam and their role in pion radiotherapy.

A new method has been developed for analyzing therapeutic negative pion beams into three LET (linear energy transfer) dose components inherent in such a beam. The technique utilizes thin silicon detectors to obtain pulse height spectra produced by the various particles in the beam traversing the detectors. It is shown that a low LET group is correlated with the incoming pions, muons and electrons; a medium LET group corresponds to protons, deuterons, tritons, and high energy alpha particles; and a high LET group is due to low energy alpha particles, 3He and recoil particles. Several beams used clinically have been studied.

Energy Transfer↗

A non-invasive technique for the control of intestinal parasites in rhesus macaques (Macaca mulatta).

Control of intestinal parasites is a major concern in maintaining the health and well-being of captive primates. This study established that percutaneous application of ivermectin was as effective as subcutaneous administration for the control of nematodes in captive rhesus macaques. The method is less intrusive than the standard subcutaneous or oral delivery routes and did not adversely affect the health of any of the study subjects.

Administration, Cutaneous↗