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D L Carlson

Publications and source records attributed to D L Carlson.

29 records · Page 2Linked to original sources
PubMed1993

Cytogenetic analysis of triploid renal carcinoma in Rana pipiens.

To provide a cytogenetic marker for nuclear transplantation experiments, triploid Rana pipiens embryos were produced. These embryos were injected with Lucké tumor herpesvirus. The chromosome profile of a renal carcinoma that developed in one of these triploid embryos was compared to the chromosomal profiles of a naturally occurring diploid renal carcinoma and a diploid renal tumor maintained as serial anterior eye chamber allografts for over 7 yr. Examination of Ag-NOR-stained chromosome spreads from the putative triploid and naturally occurring putative diploid tumor revealed the expected results. The vast majority of the chromosome spreads, 54/57 (95%) and 6/7 (86%), respectively, displayed euploid chromosome and Ag-NOR profiles: 3N = 39 with three Ag-NORs at the secondary constrictions in the long arm of chromosome 10 (10q) and 2N = 26 with two Ag-NORs in 10q. Chromosome profiles from the long-term allografted tumor were highly aneuploid (82%) and, based on their Ag-NOR content, displayed variations in their 2N, 3N, and 4N numbers. These data indicate that the majority of recently transformed triploid Lucké tumor cells can provide donor nuclei suitable for the characterization of developmental potential.

Animals↗
PubMed1993

Characterization of platelet activation induced by HLA antibodies associated with alloimmune thrombocytopenia.

The platelet-activating properties of plasma containing multispecific HLA antibodies were studied in plasma from several persons stimulated by platelet or red blood cell transfusion or by pregnancy. Antibodies were characterized by their lymphocytotoxic effects and by a monoclonal antibody antigen--capture enzyme-linked immunoassay. Plasma from each patient induced dose-dependent aggregation and release of adenosine triphosphate with antigen-positive platelet-rich plasma. Plasma from three patients induced normal aggregation and adenosine triphosphate release with platelet-rich plasma from donors who had taken platelet inhibiting medications (e.g. aspirin, piroxicam). In contrast, these platelets failed to release adenosine triphosphate when stimulated with 5 mumol/L adenosine diphosphate. Platelets were fully activated when saturated with HLA antibodies from one patient, although little or no stimulation was observed at 50% saturation suggesting that additional plasma cofactors and/or a threshold of bound antibody were required for activation. With a murine monoclonal antibody specific for P-selectin and antimurine immunoglobulin G labeled with iodine 125, plasma from each patient was found to induce P-selectin expression that was approximately 50% of that induced by 0.2 U/ml thrombin. Expression on platelets of P-selectin induced by plasma from one patient was independent of whether the donor had taken aspirin. Purified immunoglobulin G from this same patient stimulated platelet activation, as did the patient's serum, but no activation was observed with F(ab')2 fragments prepared from the immunoglobulin G. These studies demonstrate that HLA antibodies (1) mediate expression of P-selectin on the platelet surface, (2) are as potent as thrombin in activating platelets previously exposed to antiinflammatory agents, and (3) require an intact Fc domain to activate platelets.

Adenosine Diphosphate↗
PubMed1993

X-linked mixed hearing loss with stapes fixation: case reports.

X-linked mixed hearing loss with stapes fixation is a congenital, recessive anomaly. The condition is characterized by progressive mixed hearing loss, reduced vestibular responses, and congenital fixation of the stapes with perilymph gusher encountered during surgical intervention. This paper describes the audiologic history of a family with two affected male children and one carrier female child. The need for early intervention and the challenges encountered in evaluation and management are discussed.

Audiometry, Pure-Tone↗
PubMed1993

Genomic plasticity of the Lucké renal carcinoma: a review.

The differentiation potential of the Lucké renal carcinoma of the northern leopard frog, Rana pipiens, can be characterized by the nuclear transplantation procedure. Transplantation of tumor nuclei into activated and enucleated ova results, in the best of cases, in swimming larvae which fail to feed. The larvae die in about 10 to 14 days. Rescue of tumor nuclear transplantation tadpole tissue, destined to die, has been accomplished by allografting fragments of that tissue to normal hosts. The allografts persist and differentiate a diversity of tissues which cannot be distinguished by histological analysis from allografted normal control tissue. Allografts are an imperfect mode of assay for histological competence because of the immune response of the host. Lymphocytes and eosinophils invade the grafts in about 40 days. The host immune response occurs in both experimental and control allografts. Consequently, we believe that added histogenetic potential exists in the genome of the Lucké renal carcinoma. We propose that unexpressed differentiative potential of the grafted tissue can be extracted by abrogation of the immune response of the host. A herpesvirus is the etiological agent of the Lucké renal carcinoma. We currently seek to detect viral DNA in tissue derived from tumor nuclear transplant embryos. The presence of the viral genetic material in normal mitotic progeny of Lucké tumor cells, if demonstrated, raises the question of the long-term stability of differentiated cells derived from a virus tumor. Alternatively, absence of viral DNA in the tumor nuclear transplant tissue would suggest that normal differentiation ensues after elimination of the oncogenic DNA from that tissue. Loss of viral DNA may prognosticate stable differentiation.

Animals↗
PubMed1991

Allografts of tumor nuclear transplantation embryos: differentiation competence.

The developmental potential of nuclei can be studied by nuclear transplantation. Although amphibian blastula nuclei and other early embryonic nuclei are totipotent, to our knowledge no nucleus from an adult cell has ever been shown to be totipotent by this procedure. Transfer of Lucké renal carcinoma nuclei into enucleated eggs results in prefeeding swimming tadpoles. Inasmuch as these tadpoles die, rescue of this pluripotential tissue was attempted by grafting fragments of triploid tumor nuclear transplant tadpoles to the tails of normal diploid Rana pipiens hosts. Grafts of tumor nuclear transplant tadpole tissue were histologically indistinguishable from grafts of normally fertilized embryos and developed normal-appearing structures such as complete eyes, well-differentiated neural tissues, kidney tubules, and gut epithelium. Moreover, histological differentiation in tumor nuclear transplant grafts was comparable to that observed in 50-day-old normal larvae. Grafting enhanced the survival of tumor nuclear transplant tissue from no more than 14 days as part of the donor tadpole to 40 days at which time the grafts were harvested as healthy tissue. Thus, both differentiation and survival of tumor nuclear transplant tissue were augmented with the grafting procedure. Cytophotometric analysis of ploidy was used to confirm the tumor origin of the donor tissue.

Animals↗
PubMed1991

Hearing loss and hearing aid use in Hispanic adults: results from the Hispanic Health and Nutrition Examination Survey.

Data from the Hispanic Health and Nutrition Examination Survey were employed to investigate the prevalence of hearing loss and hearing aid use in Mexican-American, Cuban-American, and Puerto Rican adults. Hearing loss was 6 to 14 times more prevalent in older (ages 54 to 74) vs younger (ages 20 through 34) subjects. Cuban Americans and Mexican Americans tended to have a similar prevalence of hearing loss, whereas Puerto Ricans had markedly lower rates. Mexican-American men had higher rates of hearing loss than Mexican-American women. The prevalence of hearing aid use among hearing-impaired individuals ranged from 2% to 11%. Implications for future research are discussed.

Adult↗
PubMed1991

Utility of the backscattered ultrasonic A-mode signal for the quantitative grading of beef.

A feasibility study applicable to the IN VITRO differentiation of marbling in beef was conducted using signatures extracted from the A-mode backscattered ultrasonic signals. The energy and threshold count of these RF signals correlated well with the percentage of fat in beef sample determined by either extraction chemical test. As the value of n increases from 1 to 3 in the model for the amplitude attenuation in soft tissue, a(f) = aofn, the media of these values of n correspond from linear to nonlinear dependence of frequency in attenuation. This is observed to be analogous to beef with low to high marbling. The regressed gradient of the spectral differences between a reference spectrum from the sample with low percentage of fat and the spectra of other samples of increasing percentage of fat reveal an increase in gradient as the marbling increases. This phenomena is attributed to the change in the center frequency and the spectral bandwidth of a medium with changing physical scatterers' characteristic. These signatures, the energy, the threshold count and the gradient are then used to back predict the percentage of fat (marbling level).

Animals↗
PubMedDate not supplied

Culture of PNKT-4B cells at invasion permissive and restrictive temperatures. I. Chromosomal analysis.

PNKT-4B is an aneuploid cell line derived from a herpesvirus-induced renal adenocarcinoma of Rana pipiens that displays restricted invasion at 21 degrees C or cooler and invasion at 23 degrees C through 28 degrees C. Metaphase chromosomes obtained from subcultures (passages 297; 345-347) grown at 18 degrees C or 28 degrees C were Giemsa stained or N-banded with acidic silver nitrate. Cells grown at 18 degrees C displayed a modal chromosome number of 41, while 28 degrees C cultures displayed a modal number of 40. The distribution of the chromosomes suggests that the two temperatures may be allowing growth of different subclonal populations. N-banding of chromosomes at both temperatures revealed an increase of active nucleolar organizer regions (NORs) over normal frog tissues, 2/2N. Analysis of 200 N-banded spreads from cells grown at each temperature revealed modal numbers of 9 NORs/cell and modal numbers of 6 NOR-containing chromosomes/cell. Nine specific NOR-containing chromosomes were identified and scored. Similar distributions were observed at 18 degrees C and 28 degrees C. The data imply that the modal number of PNKT-4B has shifted since it was first described, 39, and differs at invasion-permissive and -restrictive temperatures. Increased numbers of active NORs and alterations of NOR-containing chromosomes imply an amplification of rDNA over the amount in normal frog.

Adenocarcinoma↗
PubMedDate not supplied

Sports anemia: a review of the literature.

Sports anemia has been referred to as an anemic or borderline anemic state in physically active individuals, particularly athletes. This paper is a review of literature on sports anemia, including whom it may affect and its effect on performance, and its diagnosis. In general, sports anemia has been found to be a self-limiting condition and usually does not require treatment.

Anemia↗