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M Mars

Publications and source records attributed to M Mars.

90 records · Page 5Linked to original sources
PubMed1988

Sri Lankan cleft lip and palate project: a preliminary report.

By means of a surgical expedition involving an independently financed team of surgeons, anaesthetists, nurses, orthodontists and speech therapists, 195 patients in Sri Lanka with cleft lip and palate were treated over a period of 4 weeks while over 300 patients were examined in detail to assess faciomaxillary growth, components of speech and the psychosocial impact of the untreated deformity in childhood and adult life. Lip surgery proved to be simple and safe but in certain older patients palatal closure was complicated by wide palatal shelf displacement, mucosal fibrosis and heavy bleeding. This is a preliminary report and much data has yet to be analysed but there is little doubt that impaired facial growth following palatal repair is predominantly an iatrogenic deformity.

Adolescent↗
PubMed1987

Characterization of vaccinia virus early promoters and evaluation of their informational content.

We have reported the isolation of cis-acting regulatory DNA sequences promoting expression of the herpes virus thymidine kinase gene in vaccinia virus recombinants. In this work we show that each of the inserts from recombinants VpT25, 28, 36 and 56 contains a vaccinia virus early promoter. The position of each of the early RNA start sites in the nucleotide sequence of these four vaccinia virus inserts was precisely mapped by an S1 nuclease mapping procedure. Among the four recombinants analysed only VpT56-infected cells also contained a substantial amount of a transcript with the same 5' end at late period. The insert present in VpT25 contained a new late RNA start site 50 nucleotides upstream from that of the early RNA. The four inserts were mapped on the vaccinia virus genome. We also localized the 5' end of the mRNA of a vaccinia virus host-range gene, whose DNA nucleotide sequence has recently been established. The 45 nucleotides preceding the RNA start site from most of 19 known vaccinia virus early promoters were found to be A + T-rich (at least 80%) and contained shorter A-rich (at least 60%) regions, beginning approximately 25 nucleotides upstream from the RNA start site. The information content, as expressed by the parameter Rsequence, of early vaccinia virus promoters revealed ten bits of information in the sequence of 28 nucleotides upstream from the early RNA start sites. Most of the information needed to locate an early promoter is contained within the nucleotide sequence upstream from an RNA start site. A consensus sequence consists of two blocks: the sequence AA(A/T)N(T/A)N(A/G)AAAANAANA starting at position -27 and the sequence (T/A)(C/T)N(A/T)T(A/G) starting at position -5. It was concluded that vaccinia virus early promoters may be characterized by an A + T-rich region of approximately 45 nucleotides preceding the RNA start site and include a specific 3'-terminal sequence of 28 nucleotides containing at least ten bits of information. A procedure for localizing putative early RNA start sites in nucleotide sequences is proposed.

Base Sequence↗
PubMed1987

Identification of vaccinia promoters by heterologous expression of hepatitis B surface antigen in mouse cells infected by recombinant vaccinia viruses.

DNA fragments preceding open reading frames in a conserved segment of the vaccinia virus genome (Plucienniczak A., et al. (1985) Nucleic Acids Res. 13, 985-998) were cloned into plasmids upstream of the S gene of the hepatitis B virus encoding the surface antigen (HBsAg). Recombinant vaccinia virus obtained after insertion of these constructs into the thymidine kinase gene were used to infect mouse 1D cells. HBsAg was assayed in cellular supernatants. A strong promoter was thus identified in a 295 bp fragment preceding the coding region of the 147 kDa subunit of the vaccinia RNA polymerase.

Animals↗
PubMed1987

The Goslon Yardstick: a new system of assessing dental arch relationships in children with unilateral clefts of the lip and palate.

The Goslon (Great Ormond Street, London and Oslo) Yardstick is a clinical tool that allows categorization of the dental relationships in the late mixed and or early permanent dentition stage into five discrete categories. Cases are allocated to these categories on a value judgment basis by reference to the anchor groups of the Goslon Yardstick. The categorization was sufficiently sensitive to distinguish the treatment results at different centers in this study. It is proposed that the Goslon Yardstick should facilitate cross-center studies.

Cleft Lip↗
PubMed1985

Isolation of cis-acting vaccinia virus DNA fragments promoting the expression of herpes simplex virus thymidine kinase by recombinant viruses.

Recombinant TK- vaccinia viruses containing the pBR322 sequence inserted in either orientation within the coding sequence of the viral thymidine kinase gene were constructed. They were characterized by genomic analysis, hybridization studies, reversion to wild-type virus by in vivo recombination, and rescue from their genomes of plasmids which contained all or parts of the pBR322 sequence. TK- cells were infected with one of these recombinant viruses and then transfected with pools of chimeric plasmids composed of a cloned herpes simplex virus thymidine kinase gene which contained upstream inserts of different vaccinia DNA fragments prepared by restriction or sonication. Recombination between homologous pBR322 sequences within infected cells generated selectable recombinant viruses in which expression of the herpes simplex virus thymidine kinase gene was promoted by the upstream vaccinia insert. These viruses were characterized by genomic analysis, hybridization, and in vivo or in vitro phosphorylation of (5-[125I]deoxycytidine as a specific assay for the expressed herpes simplex virus thymidine kinase. Vaccinia DNA inserts were isolated conveniently for transfer to bacteria by rescuing appropriate plasmids from the genome of recombinant viruses. The sequence of 100 nucleotides adjacent to the upstream region of the herpes simplex virus gene was determined in nine different inserts measuring 0.17 to 1.07 kilobase pairs.

Base Sequence↗
PubMedDate not supplied

The role of thromboelastography in the management of children with snake-bite in southern Africa.

In the absence of a direct laboratory test of envenomation, there is a need for an alternative mechanism for the early recognition of envenomation following snake-bite in children. A severe clinical diathesis may result either from envenomation or from the release of an inappropriate tourniquet applied as 'first-aid' often several hours before presentation to hospital. Abnormalities of clotting are associated with both events. A normal thromboelastogram (TEG) provides early recognition of patients in whom the clinical course is likely to be benign (sensitivity = 94%). An abnormal TEG identifies patients of whom 50% will develop a severe clinical diathesis. A TEG is a more accurate predictor of disease severity than International Normalized Ratio alone. The TEG does not supplant clinical observation in the management of snake-bite in children but allows stratification into high- and low-risk categories.

Child↗
PubMedDate not supplied

Expression of herpes simplex virus thymidine kinase, mediated by vaccinia virus early promoters.

We measured herpes virus thymidine kinase (HSV-TK) activity in extracts from cells infected with eight vaccinia virus recombinants (VpT), each expressing HSV-TK under the control of an early promoter previously isolated by a shotgun procedure. The HSV-TK activities induced by the VpT recombinants were compared to that produced under the control of the vaccinia virus thymidine kinase (VV-TK) promoter in VMM5-TK recombinant virus. The insert from VpT38 was approximately 10 times more efficient than the VV-TK promoter for HSV-TK expression, reflecting a similar relative strength of the promoters. HSV-TK activities induced by the other VpT recombinants varied between one and ten times that expressed by the VV-TK promoter, but the nucleotide sequence of the 5'-end region of their mRNA suggested that these values did not necessarily reflect the strength of corresponding promoters. No significant reduction in HSV-TK activity was noted for two VpT and the VMM5-TK recombinants when viral DNA replication was prevented, but a significant reduction (30 to 75%) was observed for the other six recombinants studied. These results suggested that some early genes of vaccinia virus are expressed only during the early stage of infection, whereas others continue to be expressed at the late stage. The strength of two vaccinia early promoters (VpT38, PF) relative to that of the VV-TK promoter was deduced from HSV-TK activities induced by comparable vaccinia virus recombinants.

Kinetics↗