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M Patterson

Publications and source records attributed to M Patterson.

At least 37 records · Page 2Linked to original sources
PubMed1989

An intronic region within the human factor VIII gene is duplicated within Xq28 and is homologous to the polymorphic locus DXS115 (767).

The genomic sequences recognized by the anonymous probe 767 (DXS115) are localized to two sites within Xq28. One site lies within intron 22 of the factor VIII gene (FBC). Physical mapping suggests that the second site lies within 1.2 megabases of the F8C gene. The RFLPs detected by 767 are located within the second site. Genetic data suggest that F8C and DXS115 are tightly linked (theta max = .04; Zmax = 8.30). Recombination events in meioses informative for DXS52 (St14), DXS115, and F8C suggest that DXS115 and F8C lie distal to DXS52.

Chromosome Deletion↗
PubMed1988

Reconstruction and pathology in macrodactyly.

We report a case of macrodactyly in which a finger was shortened and the nail bed and root implanted proximally using a vascularized pedicle. Electron microscopic findings showed that there was focal and segmental degeneration of myelin sheath and neurofilaments of axon.

Female↗
PubMed1988

Differential regulation of the yeast CDC7 gene during mitosis and meiosis.

The product of the CDC7 gene of Saccharomyces cerevisiae is known to be required in the mitotic cell cycle for the initiation of DNA replication. We show that changes in transcript levels do not account for this stage-specific function, since the steady-state mRNA concentration remains constant at 1 copy per cell throughout the cell cycle. By measuring the cell division capacity of a cdc7::URA3 mutant after loss of a single-copy plasmid containing the CDC7 gene, we show that the CDC7 protein is present in at least 200-fold excess of the amount required for a single cell division. These results appear to exclude periodic transcription or translation as a means by which CDC7 function is regulated. In contrast, the CDC7 protein is known to be dispensable for meiotic S phase, but is required for synaptonemal complex formation and recombination. We found that the CDC7 transcript level does vary during meiosis, reaching a maximum near the time at which recombination occurs. Meiotic spores containing a cdc7 null allele germinate but fail to complete cell division. Apparently the excess CDC7 product present in mitotic cells is physically excluded from the spores (or becomes inactivated) and must be produced de novo after germination. The cdc7-1 allele had previously been shown to confer a reduction in the rate of induced mutation. We show that the cloned wild-type CDC7 gene not only complements this defect, but that when the CDC7 gene is on a multiple copy plasmid, induced mutagenesis is increased. Therefore, in contrast to the excess CDC7 activity for cell division, the level of activity for some error-prone repair process may be normally limiting.

Cell Cycle↗
PubMed1988

Linkage studies in a large fragile X family.

We have analyzed the segregation of five loci in the region Xq27/28 in a large family affected by the fragile X syndrome. The marker DXS115 (767) is shown to be polymorphic with the enzyme PstI, as well as with BstXI. This marker will be useful in the analysis of both fragile X and haemophilia A families. The data presented here are consistent with the following order of loci: Xcen-F9-DXS105(cX55.7,55E)-DXS98(4D-8)- FRAXA-DXS52(St14)-DXS115(767)-qter.

DNA Probes↗
PubMed1988

A novel monoclonal antibody based diagnostic test for alpha-thalassemia-1 carriers due to the (-SEA/) deletion.

The presence of minute amounts of embryonic zeta-globin chains in adult hemolysates is a marker for carriers of alpha-thalassemia-1 resulting from (--SEA/) deletion. Recently, we developed a murine monoclonal antihuman embryonic zeta-globin chain antibody, 8E8. By using this antibody, we have now established a slot-blot immunobinding assay for the rapid detection of zeta-globin chains in adult hemolysates. zeta-globin chains were found to be present in 30 blood samples obtained from individuals who were carriers of alpha-thalassemia-1. In another 30 blood samples from individuals who were not carriers of the (--SEA/) deletion, zeta-globin chains were not detected. This simple diagnostic test can be used in appropriate populations to identify those couples at risk of conceiving fetuses afflicted with the Hb Bart's hydrops fetalis syndrome due to homozygous alpha-thalassemia.

Antibodies, Monoclonal↗
PubMed1987

Mapping of DNA markers close to the fragile site on the human X chromosome at Xq27.3.

We report the identification of a new RFLP detected by the DNA probe MN12, which is linked to both the fragile site on the X chromosome at Xq27.3 and the highly polymorphic locus detected by St14 (DXS52). In situ mapping confirms the localisation of MN12 distal to the fragile site. A detailed physical analysis of this region of the X chromosome using pulsed-field gel electrophoresis has shown that MN12, St14 and DX13 (DXS15) are physically linked within a region of 470kb. A long range restriction map around the MN12 locus reveals at least two candidate HTF islands, suggesting the existence of expressed sequences in this region.

Base Sequence↗
PubMed1987

Molecular analysis of the Duchenne muscular dystrophy region using pulsed field gel electrophoresis.

Genetic and molecular studies show that the Duchenne muscular dystrophy (DMD) locus at Xp21 is large and complex. We have analyzed this region using pulsed field gel electrophoresis (PFGE) and have determined physical distances between Xp21 probes. The sum of the sizes of the Sfil restriction fragments detected by these probes is greater than 4000 kb. The deletion endpoints in two DMD patients were detected by observing changes in these restriction fragments. In addition, the Xp21 breakpoint for the X;1 translocation in an affected female was mapped. These results demonstrate the applicability of PFGE for analysis of Xp21, and should facilitate the mapping of other translocations and deletions in this region, some of which lead to glycerol kinase deficiency and adrenal hypoplasia as well as DMD.

Chromosome Deletion↗
PubMed1987

Physical mapping studies on the human X chromosome in the region Xq27-Xqter.

We have characterized three terminal deletions of the long arm of the X chromosome. Southern analysis using Xq27/q28 probes suggests that two of the deletions have breakpoints near the fragile site at Xq27.3. Flow karyotype analysis provides an estimate of 12 X 10(6) bp for the size of the deleted region. We have not detected the deletion breakpoints by pulsed-field gel electrophoresis (PFGE) using the closet DNA probes, proximal to the fragile site. The physical distance between the breakpoints and the probes may therefore be several hundred kilobases. The use of the deletion patients has allowed a preliminary physical map of Xq27/28 to be constructed. Our data suggest that the closest probes to the fragile site on the proximal side are 4D-8 (DXS98), cX55.7 (DXS105), and cX33.2 (DXS152). PFGE studies provide evidence for the physical linkage of 4D-8, cX55.7, and cX33.2. We have also found evidence for the physical linkage of F8C, G6PD, and 767 (DXS115), distal to the fragile site.

Cell Line↗
PubMed1987

Chromosome-specific alpha satellite DNA from human chromosome 1: hierarchical structure and genomic organization of a polymorphic domain spanning several hundred kilobase pairs of centromeric DNA.

The human alpha satellite repetitive DNA family is organized as distinct chromosome-specific subsets localized to the centromeric region of each chromosome. Here, we report he isolation and characterization of cloned repeat units which define a hierarchical subset of alpha satellite on human chromosome 1. This subset is characterized by a 1.9-kb higher-order repeat unit which consists of 11 tandem approximately 171-bp alpha satellite monomer repeat units. The higher-order repeat unit is itself tandemly repeated, present in at least 100 copies at the centromeric region of chromosome 1. Using pulsed-field gel electrophoresis we estimate the total array length of these tandem sequences at the centromere of chromosome 1 to be several hundred kilobase pairs. Under conditions of high stringency, the higher-order repeat probe hybridizes specifically to chromosome 1 and can be used to detect several associated restriction fragment length DNA polymorphisms. As such, this probe may be useful for molecular and genetic analyses of the centromeric region of human chromosome 1.

Chromosome Mapping↗
PubMed1987

Hemophilia B (Christmas disease) variants and carrier detection analyzed by DNA probes.

We have used two strategies to study 14 hemophilia B families from 11 kindreds for possible carrier detection and prenatal diagnosis. First, we sequentially used the Factor IX probes (sequentially with restriction enzymes Taq I, Xmn I, and Dde I), and the linked probes p45h (Taq I), p45d (Pst I), and 52a (Taq I) for restriction fragment length polymorphism (RFLP) analysis. Second, we searched for useful variant Taq I digestion fragments using the Factor IX complementary DNA. Two separate new Taq I variants in exon VIII were identified. Using both strategies, 11 of 14 families (from 9 of 11 kindreds) were informative for further studies. In five kindreds studied in detail, the carrier status of all 11 at risk females was determined and prenatal diagnosis could be offered to the offsprings of each of the six carriers identified. Thus, in this study, we have identified a higher proportion of informative families than has previously been reported.

DNA↗
PubMed1987

Ring uncemented hip replacements. The results of revision.

Since 1964, 3573 uncemented Ring total hip replacements of all types have been performed; 194 (5.4%) have required revision for infection, loosening or breakage. Of these, 102 were available for review; 81 had satisfactory results five years after operation. These results are better than many of those reported after revision of cemented hip replacements. It is suggested that the absence of cement makes revision easier because bone erosion rarely occurs.

Aged↗
PubMed1986

Embryonic zeta-globin chains in adults: a marker for alpha-thalassemia-1 haplotype due to a greater than 17.5-kb deletion.

Hemolysates from adults with the alpha-thalassemia-1 haplotype due to the greater than 17.5-kb deletion of both alpha-globin genes from the same chromosome were found to contain embryonic zeta (zeta)-globin chains (alpha-globin-like chains), as determined by a specific and sensitive radioimmunoassay and an electrophoretic technique. zeta-Globin chains were not present in hemolysates from adults with deletion of a single alpha-globin gene from one or both chromosomes. These results indicate that zeta-globin chains, which can be assayed by immunologic techniques, can serve as markers for the alpha-thalassemia-1 haplotype due to the greater than 17.5-kb deletion. The ability to detect zeta-globin chains may be useful in populations in which the gene frequency of the greater than 17.5-kb deletion is high, for screening couples at risk of having offspring with homozygous alpha-thalassemia.

Adult↗
PubMed1986

Correlations between in vitro dissolution, in vivo bioavailability and hypoglycaemic effect of oral glibenclamide.

A study has been carried out investigating four different marketed oral preparations of glibenclamide, correlating the effectiveness of the drug in these preparations in lowering plasma glucose concentrations with the in vitro dissolution of the drug, measured by the British Pharmacopoeal and Desaga methods, and the in vivo bioavailability, assessed in 12 healthy human volunteers. The two dissolution methods yielded different rank orders of ease of dissolution of the drug from the various preparations; the findings of neither dissolution method correlated adequately with the results of the in vivo bioavailability studies, which correctly predicted the abilities of the preparations to reduce plasma glucose concentrations. Relative to an oral glibenclamide solution the bioavailabilities of the drug from three tablet preparations were 0.69, 0.49 and 0.24. The mean elimination half-life of the drug was 1.5 h and assuming complete bioavailability of the drug from oral solution the mean systemic clearance was 0.095 l kg-1h-1, and the mean apparent volume of distribution was 0.20 l kg-1. It is concluded that it may be unsafe to use in vitro dissolution data as a basis for assessing the bioequivalences of different glibenclamide preparations intended for oral use.

Adult↗
PubMed1986

Chronic esophageal ulceration after endoscopic sclerotherapy.

Ulceration at the site of injection is a common sequel of endoscopic sclerotherapy. Most postsclerotherapy ulcers heal spontaneously, usually within 3 weeks. We report a patient who developed a large esophageal ulcer after sclerotherapy, which did not heal despite 2 years of aggressive medical therapy. He bled twice from the ulcer. This is the first report in which such an ulcer has been followed sequentially for 2 years and has remained unhealed.

Aged↗
PubMed1986

Molecular characterization of cell cycle gene CDC7 from Saccharomyces cerevisiae.

The product of the CDC7 gene of Saccharomyces cerevisiae appears to have multiple roles in cellular physiology. It is required for the initiation of mitotic DNA synthesis. While it is not required for the initiation of meiotic DNA replication, it is necessary for genetic recombination during meiosis and for the formation of ascospores. It has also been implicated in an error-prone DNA repair pathway. Plasmids capable of complementing temperature-sensitive cdc7 mutations were isolated from libraries of yeast genomic DNA in the multicopy plasmid vectors YRp7 and YEp24. The complementing activity was localized within a 3.0-kilobase genomic DNA fragment. Genetic studies that included integration of the genomic insert at or near the CDC7 locus and marker rescue of four cdc7 alleles proved that the cloned fragment contains the yeast chromosomal CDC7 gene. The RNA transcript of CDC7 is about 1,700 nucleotides. Analysis of the nucleotide sequence of a 2.1-kilobase region of the cloned fragment revealed the presence of an open reading frame of 1,521 nucleotides that is presumed to encode the CDC7 protein. Depending on which of two possible ATG codons initiates translation, the calculated size of the CDC7 protein is 58.2 or 56 kilodaltons. Comparison of the predicted amino acid sequence of the CDC7 gene product with other known protein sequences suggests that CDC7 encodes a protein kinase.

Amino Acid Sequence↗
PubMed1985

Cryptosporidiosis outbreak in a day-care center.

An outbreak of diarrhea occurred in a day-care center in San Marcos, Tex, in August 1984. At the time of this study, the center was caring for 81 children aged 2 months through 5 years. A single stool specimen was collected from each of 50 children (62%). Cryptosporidium oocysts and Giardia lamblia cysts were each identified in stool specimens from 18 children. Three children had both parasites present in the same stool specimen. Echovirus 30 was identified in 19 of 25 stools cultured. Although three pathogens were circulating simultaneously in this group of children, only the presence of Cryptosporidium oocysts was associated with the occurrence of a diarrheal illness. Cryptosporidium may be a common cause of diarrhea in children who attend day-care centers.

Animals↗
PubMed1985

Healing of endoscopic biopsy sites in the human rectum.

The time required in man for a rectal ulcer created with endoscopic biopsy forceps to heal is unknown. To answer this question, we created a large ulcer (approximately 8 mm in diameter) and a smaller ulcer (approximately 4 mm in diameter) in four healthy young men and followed the healing of the ulcers by visual examination every 4 days. Complete healing of the large ulcer had not occurred on days 4 and 8, while by day 12, three had healed and by day 16, all four had disappeared. Of the small ulcers, two had healed by day 8, and all had healed by day 12. This study suggests that it takes approximately 8-12 days for an artificially created rectal lesion to heal completely.

Adult↗