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M Graham

Publications and source records attributed to M Graham.

At least 55 records · Page 3Linked to original sources
PubMed1987

The indirect flight muscle of Drosophila accumulates a unique myosin alkali light chain isoform.

Mapping of the 5' and 3' ends of the Drosophila myosin alkali light chain (MLC-ALK) mRNA by S1 nuclease and primer extension assays has shown that the primary transcripts are identical irrespective of the time in development that the RNA was prepared. As shown by S1 nuclease experiments these transcripts are alternatively spliced in a tissue-specific fashion generating mRNAs that encode tissue-specific protein isoforms. Antibodies were raised to synthetic peptides identical in sequence to the unique portion of each protein. Western blots of one-dimensional polyacrylamide gels using the type-specific antibodies confirmed and extended the results obtained from the S1 nuclease experiments. The indirect flight muscle is the only tissue in the adult that accumulates the alternatively spliced mRNA. The choice between splicing pathways involves the use of a nonconsensus 3' splice junction in larvae and in the tubular muscles of adults, whereas in the indirect flight muscle of the adult only consensus sequences are utilized. The involvement of a trans-acting factor to activate the nonconsensus splice site in the myotubes of larvae and the tubular myotubes of adults is proposed.

Animals↗
PubMed1986

Chromosome 8 breakpoint far 3' of the c-myc oncogene in a Burkitt's lymphoma 2;8 variant translocation is equivalent to the murine pvt-1 locus.

The 2;8 variant translocation of human Burkitt's lymphomas is closely related cytogenetically to the t(6;15) of murine plasmacytomas; both involve a reciprocal exchange between the Ig kappa locus and a band region indistinguishable from that bearing the c-myc oncogene. To define their molecular relationship, we have compared cloned chromosome 8 DNA from the t(2;8) breakpoint in the human Burkitt's lymphoma JBL2 with cloned DNA from the murine pvt-1 locus, the major chromosome 15 breakpoint region in murine t(6;15). DNA sequencing and Southern blot analysis shows that these two regions are homologous. Thus the t(2;8) in JBL2 is the molecular equivalent of many murine t(6;15). The murine pvt-1 locus lies an unknown distance 3' of c-myc; analysis of DNA from several tumours with c-myc amplification reveals that pvt-1 is co-amplified in at least one case, placing pvt-1 approximately 100-500 kb 3' of c-myc. The significance of these results with respect to the role of pvt-1 in tumorigenesis is discussed.

Animals↗
PubMed1986

An inexpensive microcomputer digital imaging system for densitometry: quantitative autoradiography of insulin receptors with 125I and LKB Ultrofilm.

This article describes a video digitizing system designed for measuring film optical density. The system, which is based on a 6-bit (64 gray level) digitizer, solid state video camera, and Apple II microcomputer, digitizes a rectangular area selected by the operator and converts the gray level values into preselected standard units. In order to develop autoradiographic standard curves for quantitative autoradiography with 125I-insulin, liver slices labeled with 125I-insulin and plastic sections containing known amounts of tritium were apposed to the same sheet of LKB Ultrofilm for exposures of 1-7 days. The results indicate that 3H plastic standards can be used to calibrate QAR of 125I-labeled ligands with LKB Ultrofilm. The Apple system was also used to measure binding of 125I-insulin to the external plexiform layer (EPL) in slices of the rat olfactory bulb. Results suggest that the EPL has two binding sites for insulin, a high affinity site with Kd = 1.0 X 10(-8) M and a low affinity site having a Kd = 1.4 X 10(-5) M.

Animals↗
PubMed1986

Proviral integration site Mis-1 in rat thymomas corresponds to the pvt-1 translocation breakpoint in murine plasmacytomas.

Two loci independently implicated in T-and B-lymphocyte neoplasia are shown to be equivalent. The Mis-1 locus is a common proviral integration site in retrovirally induced rat T lymphomas, while the pvt-1 locus on murine chromosome 15 frequently translocates to the kappa locus in plasmacytomas bearing 6;15 translocations. By comparing cloned sequences, we show that pvt-1 is the murine homolog of Mis-1.

Animals↗
PubMed1985

Variant (6;15) translocations in murine plasmacytomas involve a chromosome 15 locus at least 72 kb from the c-myc oncogene.

The variant (6;15) translocations in murine plasmacytomas join the myc oncogene-bearing band of chromosome 15 and the immunoglobulin kappa band of chromosome 6. We recently cloned a region from chromosome 15 linked to C kappa and have now used probes from that region to define the major locus of plasmacytoma variant translocations, which we denote pvt-1. In five of nine plasmacytomas we analysed, the 6;15 translocation resulted from reciprocal recombination between the C kappa locus and a 4.5-kb region of pvt-1. Moreover, nearby we located the region shown by others to have undergone a complex (15;12;6) translocation in plasmacytoma PC7183. All the chromosome 6 breakpoints fell between 1 and 3 kb 5' to C kappa but only two were near J kappa genes. Thus the J kappa -C kappa region appears to be a recombination 'hot spot' in lymphocytes, but the breaks are unlikely to be mediated via V/J recombination enzymes. Comparison of a cloned 108-kb region across pvt-1 and another of 52 kb across c-myc established that the pvt-1 breakpoints lie at least 72 kb from the c-myc promoters. Since c-myc is expressed at a substantial level, the 6;15 translocation apparently activates c-myc. Activation may occur directly, at a remarkable distance along the chromosome, or indirectly, via a putative pvt-1 gene product.

Animals↗
PubMed1985

Diamond-Blackfan syndrome in adult patients.

Two adults with pure red cell aplasia are described. No extrinsic etiologic mechanisms were identified. Evidence of anemia was long-standing and varied in severity. Musculoskeletal abnormalities (webbed neck, Sprengel's and Klippel-Feil deformities, and hand abnormalities) were similar to those seen in the congenital form of red cell aplasia (Diamond-Blackfan syndrome). As in the congenital variety, adrenal cortical steroids resulted in hematologic repair. These observations suggest that congenital (Diamond-Blackfan) pure red cell aplasia may be first recognized in adulthood and that steroids provide a potential therapeutic modality.

Adult↗
PubMed1985

An unsuspected arsenic poisoning murder disclosed by forensic autopsy.

An unsuspected case of homicidal arsenic poisoning, clinically thought to be a primary hematopoietic disorder, was uncovered by an expanded toxicologic screen which is performed in all medical examiner's cases in which the decedent displays gastrointestinal symptoms prior to death. Arsenic concentrations were: blood, 7.2 mg/liter; liver, 15 mg/kg; and kidney, 6 mg/kg.

Adult↗
PubMed1982

Rate of diffusion of Solu-Medrol across the silastic membranes of breast prostheses-an in vitro study.

Many plastic surgeons have used steroids in breast prostheses in augmentation and postmastectomy reconstruction to prevent capsular contracture. The detection and incidence of complications have increased during the last several years. It is probable that the incidence of complications is related to two factors. First, clinicians have used the same doses in the smaller outer compartments of bilumen implants, giving a much higher concentration of steroid. Second, the more recent implants have thinner envelopes. Tritiated Solu-Medrol was placed in the outer lumen of the bilumen Heyer-Schulte, McGhan, and Surgitek prostheses, and in the only lumen of inflatable Mammatech and Heyer-Schulte prostheses. Diffusion of the Solu-Medrol from each of these identically sized prostheses into the surrounding saline bath was measured with a liquid scintillation counter. Diffusion rates provided concentration-dependent, as predicted by Donnan-Gibbs equilibrium. The silicon gel in bilumen implants was found to represent a second Donnan-Gibbs equilibrium and result in a lower diffusion rate because of affinity for the steroid.

Breast↗
PubMed1981

Staging Meniere's disease and reporting results in Meniere's disease: symposium panel discussion.

At its recent spring meeting, the American Neurotologic Society devoted a portion of its program to a symposium on staging Meniere's disease and reporting results. One of the problems discussed, was which preoperative audiogram should be used for reporting results of any treatment. I think that it is very important that we, as otologists, try to look at Meniere's disease or any inner ear dysfunction in a more scientific way. Some of you may feel, on initial evaluation of this material, that it is too cumbersome to be practical in your daily clinical work. However, we feel we have put forth a reasonable staging system and method of reporting results that can be quite helpful once the simple routine of using them has become established. The vertigogram, for example, which is designed to be very simple and not require any sophisticated equipment, should be as easy to read as an audiogram. If we try to approach the vagaries of Meniere's disease or any inner ear dysfunction in a more scientific fashion, I am sure that in several years we will be in a much better position collectively to evaluate our results and to help our patients. This type of comprehensive staging system for all of the components in Meniere's disease or any inner ear dysfunction will enable us to objectify diagnoses and treatment results so that they can be easily compared. We have put forth some of the ideas and methods that we think will help us arrive at a consensus for reporting results. We encourage you to try some of the suggestions presented in this article and welcome your comments and ideas for improving this staging system and method for reporting results.

Audiometry↗
PubMed1979

Genital cancer in wives of penile cancer patients.

We identified the wives or ex-wives of 227 males of the 256 reported with cancer of the penis to the New York State Cancer Registry from Upstate New York from 1960-64. Utilizing the Registry, death certificates, hospital and physician records, we ascertained those wives who developed cancer at any site from 1951-1975. We generated expected numbers of cases of cancer at each site by applying the age specific incidence rates experienced by women of a specific age in a specific year designated by the age of the wife of the index case in each year, estimating withdrawals from age-specific death rates. Thus, our expected numbers are based on the experience of the women in Upstate New York with traits like those of spouses of the men in the same population with cancer of the penis. We found significantly more cases of cancer of the cervix than expected. This was not true for other sites of cancer.

Adult↗
PubMed1979

Within-species variation in the development of ultrasonic signaling of preweanling rats.

The development of litter and individual differences in the rate of ultrasonic signaling of neonatal rats was studied. Systematic variations among litters and individuals emerged, without differential treatment. These differences were not correlated with variations in general development as indexed by body weight. Two experiments using a cross-fostering design showed that litter differences developed independently of variations in postnatal environment. These results indicate that the variations among litters in ultrasound rate have a prenatal, possibly genetic, etiology and may represent reliable indicants of response to environmental stress.

Animals↗
PubMed1979

Ultrasound diagnosis of interstitial pregnancy: findings and pitfalls.

The diagnosis of an unruptured interstitial gestation can be made by means of ultrasound examination. The most specific finding is an incomplete myometrial mantle around the sac. An eccentrically placed sac and failure to demonstrate the sac within the uterine cavity, i.e., near the internal os on the longitudinal scans, may be helpful ancillary findings. The differential diagnosis must take into consideration a pregnancy within one horn of a bicornuate uterus and a pregnancy within a myomatous uterus. Although this is a rare condition, it carries significant mortality if it ruptures. Diagnosis prior to rupture will reduce mortality and offer the possibility of preserving reproductive capabilities.

Adult↗
PubMed1979

Plasma pentazocine radioimmunoassay.

A sensitive and specific radioimmunoassay of dog and human plasma pentazocine is described. Rabbit antiserum and the second antibody method separated bound from free pentazocine. The radioimmunoassay employed an 125I-labeled radioligand and required extraction from the sample prior to quantitation. The method had a detection limit of approximately 200 pg/assay tube (1 ng/ml). The assay was used successfully to measure pentazocine in the plasma of beagle hounds given 0.3 mg of pentazocine/kg iv. The decline in plasma levels fitted a two-compartment body model with a 100-min mean overall half-life and a 3.2-liters/hr mean plasma clearance rate.

Animals↗
PubMed1979

Motion parallax as an independent cue for depth perception.

The perspective transformations of the retinal image, produced by either the movement of an observer or the movement of objects in the visual world, were found to produce a reliable, consistent, and unambiguous impression of relative depth in the absence of all other cues to depth and distance. The stimulus displays consisted of computer-generated random-dot patterns that could be transformed by each movement of the observer or the display oscilloscope to simulate the relative movement information produced by a three-dimensional surface. Using a stereoscopic matching task, the second experiment showed that the perceived depth from parallax transformations is in close agreement with the degree of relative image displacement, as well as producing a compelling impression of three-dimensionality not unlike that found with random-dot stereograms.

Cues↗