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Biomedical subjects

W H Petri

Publications and source records attributed to W H Petri.

At least 19 recordsLinked to original sources
PubMed1993

Comparative analysis of the sequence and structure of two Drosophila melanogaster genes encoding vitelline membrane proteins.

Two Drosophila melanogaster vitelline membrane protein-encoding genes (VM), located at polytene band positions 26A and 34C, have been cloned and comparatively characterized at the nucleotide level. Sequence analysis of genomic and cDNA clones for the two genes, VM26A.1 and VM34C.1, indicates that both are similarly organized with a central highly conserved domain [Scherer et al., Dev. Biol. 130 (1988) 786-788] which is flanked by unrelated regions, and that both genes lack introns. Comparison of the upstream regions reveals that both VM genes contain a hepatmeric element identical to one associated with the D. melanogaster yolk protein-encoding genes (YP). This heptamer occurs in the specific 5' flanking region responsible for ovarian temporal- and tissue-specific control in both VM and YP genes. A putative chorion transcription factor 2 site is also associated with an upstream control element of VM26A.1, but not with any sequenced portion of VM34C.1.

Amino Acid Sequence↗
PubMed1993

Developmental control elements in the promoter of a Drosophila vitelline membrane gene.

DNA fragments from the 5' flanking region of Drosophila melanogaster vitelline membrane gene VM26A1 were fused to hsp/lacZ reporter genes, reintroduced via P-element-mediated germ line transformation, and functionally assayed by histological staining for beta-galactosidase activity. A developmental control element capable of promoting the basic vitelline membrane (VM) expression pattern was found within a 176-bp region. Additional multiple genetic control elements were found to be involved in modifying the level and spatial pattern of reporter gene expression but these required the 176-bp element in order to function. Unexpectedly, in isolation this 176-bp core element also promotes abnormal expression of the reporter gene in border cells of stage 8 and 9 egg chambers. This abnormal border cell expression is apparently suppressed in the native gene by an adjacent negative control element.

Animals↗
PubMed1993

Clinical evaluation of antibiotic-supplemented bone allograft.

Antibiotic-supplemented bone allograft (ASBA) was originally developed for treatment of combat-acquired, avulsive defects of the oral and maxillofacial skeleton. Earlier findings in experimental wound models showed that ASBA resulted in significantly improved wound repair of infected osseous defects when compared with conventional treatment. In this study, ASBA was evaluated in paired, comparable, mandibular third molar sockets and compared with the findings following conventional surgical removal. The results of this assessment showed that wound healing was significantly improved with the use of ASBA. Evidence produced by this clinical evaluation of ASBA suggests its potential use for other surgical bone defects when grafting is precluded by the risk of infection as a result of contamination by oral flora.

Adult↗
PubMed1991

Evaluation of antibiotic-supplemented bone allograft in a rabbit model.

The use of an antibiotic-supplemented bone allograft (ASBA) as a material for placement in infected mandibular fractures was investigated in a rabbit model. In phase I of this project, fractures were created in the mandibles of 30 New Zealand white rabbits and injected with 5 x 10(6) colony-forming units of Staphylococcus aureus and Bacteroides melaninogenicus. The animals were divided into three treatment groups (A, B, or C) and treated with conventional treatment (CT), CT plus demineralized bone powder, or CT plus ASBA. In phase II, bone defects were created in the mandibles of 17 New Zealand white rabbits and then grafted with ASBA. Assessment of healing and vascular ingrowth was made at 2-day intervals through 3 weeks postoperatively, and then weekly until termination at 60 days postoperatively. Phase I results showed significantly enhanced healing in the ASBA-treated group when compared with the other treatment methods and healed fracture strength, which was comparable to the nonfractured, contralateral mandibular angle. Phase II results demonstrated vascular structures in the ASBA material by 4 days postoperatively and osteogenesis by 12 days postoperatively.

Animals↗
PubMed1988

Drosophila vitelline membrane genes contain a 114 base pair region of highly conserved coding sequence.

Two Drosophila vitelline membrane (VM) genes located at polytene band positions 26A and 34C have been characterized at the nucleotide level. Sequence comparison of the two genes VM26A.1 and VM34C.1 has revealed a similar 114 base pair region centrally located in the coding regions of both genes. The conserved region has a 91% homology at the nucleic acid level and a 100% conservation at the amino acid level. This suggests a common evolutionary origin for these VM genes and indicates that a strong selective pressure exists to maintain a specific polypeptide sequence in a domain of the proteins.

Animals↗
PubMed1986

Factors which equalize the representation of genome segments in recombinant libraries.

Genomic segments which contain inverted repetitions longer than 300 bp are frequently lost from recombinant libraries grown on rec+ hosts. We have found that 9% of phage lambda clones that contain 15-20-kb insertions of human or Drosophila DNA are inhibited on rec+ hosts and as a result will become under-represented in amplified genomic libraries. We have therefore examined several factors of both host and vector origin which affect the fidelity of representation of genomic sequences in recombinant DNA libraries constructed in bacteriophage lambda vectors. This loss may be diminished if the vector carries either a chi element or a functional gam gene. The most successful approach, however, involves using a host with mutations in recB, recC, and sbcB, or in recD. We have shown that recombinant clones which require such mutant hosts for growth are somewhat more likely to contain DNA derived from loci in the genome which are polymorphic than are clones recovered on conventional hosts.

Animals↗
PubMed1985

Isolation and chromosomal location of putative vitelline membrane genes in Drosophila melanogaster.

cDNA clones for two Drosophila vitelline membrane genes have been identified on the basis of: (i) stage and tissue specificity of transcription and (ii) size and amino acid content of the translation product. Cross-hybridization data suggest that DmcMM99 and DmcMM115 are members of a multi-gene family which includes at least three members, all of which reside on the left arm of the second chromosome. DmcMM99 and DmcMM115 originate from polytene band positions 34C and 26A, respectively. A third, cross-hybridizing gene resides at position 32EF. Southern analysis of a genomic clone, lambda LS1, homologous to DmcMM115, indicates that two vitelline membrane genes may be clustered at the 26A site.

Animals↗
PubMed1985

A comparison of freeze-dried allogeneic and fresh autologous vascularized rib grafts in dog radial discontinuity defects.

The limitations of autologous vascularized grafts include morbidity at the donor site and the increased surgical time associated with graft retrieval. To overcome these limitations, freeze-dried allogeneic and fresh autologous vascularized rib grafts were compared in 6-cm mid-radial defects of dogs. There was no statistically significant difference between the two graft systems when postoperative radiographs, in vivo intraarterial angiograms, and histologic evaluation of vessel patency were compared. However, clinical assessment of graft stability favored the autologous grafts, and force deflection tests revealed that the freeze-dried grafts had only 64% of the graft strength of the fresh autologous grafts at the end of the experiment at 26 weeks.

Angiography↗
PubMed1984

Localization of a gene for a minor chorion protein in Drosophila melanogaster: a new chorion structural locus.

A minor chorion protein (called s70) with an approximate molecular weight of 70,000 D has been characterized in Drosophila melanogaster. The Staket geographic strain was found to carry an electrophoretic variant of this eggshell component and was used to determine the chromosomal location of the s70 gene. Our results establish a new locus for a chorion gene near yellow on the X chromosome and represent the first mapping of a quantitatively minor eggshell protein.

Animals↗
PubMed1984

Osteogenic activity of antibiotic-supplemented bone allografts in the guinea pig.

This study evaluated the osteogenic potential of bone allografts supplemented with up to 1000 times the minimum inhibitory concentration of cephalothin and tobramycin effective against Staphylococcus aureus and Pseudomonas aureus. Mineralized and demineralized bone allografts with and without antibiotics were compared in calvarial defects of guinea pigs. Strontium-85 uptake and histologic evaluation indicated there was no significant difference in osteogeneic activity between nonantibiotic-supplemented allografts and antibiotic-supplemented allografts.

Animals↗
PubMed1984

The effects of antibiotic-supplemented bone allografts on contaminated, partially avulsive fractures of the canine ulna.

The use of antibiotic-supplemented bone allograft as a material for placement in contaminated fractures of the dog ulna was investigated. Demineralized, freeze-dried bone allografts mixed with antibiotics and gelatin were placed in five fractures contaminated with Staphylococcus aureus (Washington Hospital strain) and Pseudomonas aeruginosa (PA 220). The results of treatment with antibiotic-supplemented bone allografts were compared with the results of conventional treatment in five additional experimental animals in which fractures contaminated with S. aureus and P. aeruginosa were created. The five fractures treated by conventional methods developed acute osteomyelitis and nonunion, whereas the ASBA-treated fractures resulted in bone union without infection. ASBA-treated fractures were stable and had 89% of the shearing strength of the non-fractured, contralateral ulnae five months after treatment.

Animals↗