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D Blair

Publications and source records attributed to D Blair.

At least 91 records · Page 5Linked to original sources
PubMed1990

Structure, tissue-specific expression, and transforming activity of the mouse met protooncogene.

A 6.7-kilobase met complementary DNA (cDNA) was isolated from a pcD cDNA library prepared from C3H mouse fibroblast cell line polyadenylated RNA. Sequence analysis of 6.7-kilobase met cDNA insert revealed that it contained the entire open reading frame and shared an overall homology of 88.1% with the human met gene. Using the mouse met cDNA as probe, high levels of met expression were observed in the kidney, brain, lung, skin, and embryonic tissue as well as in several factor responsive mouse myeloid cell lines. Under SV40 promoter control, the mouse met protooncogene cDNA in the pCD vector was able to transform NIH 3T3 cells. These transformed cells possess multiple copies of mouse met cDNA and exhibit properties of malignant cells, including growth in soft agar and induction of tumors in nude mice. Tumor explant cell lines analyzed by Western blot also reveal the presence of high levels of Mr 170,000 and 140,000 met protein product(s).

Amino Acid Sequence↗
PubMed1989

Studies on cardiovascular fluke (Digenea: Spirorchiidae) infections in sea turtles from the Great Barrier Reef, Queensland, Australia.

Twenty-seven sea turtles (23 Chelonia mydas and four Eretmochelys imbricata) from northeast Queensland were found to be infected with cardiovascular flukes and/or their eggs. Five had originated from turtle farms in the Torres Strait, five from an oceanarium on Magnetic Island (146 degrees 56'E, 19 degrees S) and the remainder from coral reefs in the Torres Strait or near Townsville. The incidence of flukes and/or eggs in the groups was 4.8 per cent (5 of 104), 33.3 per cent (5 of 15) and 72.2 per cent (17 of 22), respectively. Affected animals ranged in size from 18 to 108 cm (curved carapace length) and weighed between 0.5 and 77 kg. The average number of flukes per host was 47. Flukes were recovered from the three chambers of the heart and major vessels (right aortic arch and brachiocephalic artery), where they were attached to the walls or free in the lumen. They were subsequently identified as Haplotrema spp. and/or Learedius spp. In 59.2 per cent (16 of 27) of turtles, flukes were not found, although their eggs were detected microscopically. Gross pathological changes associated with the presence of flukes included thickening and hardening of arterial walls (four turtles), thrombus formation (three), chronic pneumonia (two) and an excess of pericardial or peritoneal fluid (four). Microscopically, the essential changes was that of chronic inflammation, as evidenced by the proliferation of epithelial cells, reticulo-endothelial cells and fibroblasts in areas accessible to flukes and/or eggs. Multiple diffuse egg granulomas were a prominent feature of most organs, the spleen and lungs being predilection sites. Proliferative changes had occurred in the endocardium and in the endothelium of vessels supplying the spleen, stomach, intestine and pancreas (18 turtles). The walls of major arteries, lungs, liver, brain, crop and stomach were also acutely inflamed (eight turtles). Haemorrhage was recorded in the lungs and/or brain of eight turtles with heavy fluke infestations. Other vascular changes, viz. congestion, oedema and hypertrophy of arterial/arteriolar walls, resulted from the inhibition of blood flow by parasitic emboli.

Animals↗
PubMed1989

Restriction enzyme mapping of ribosomal DNA can distinguish between fasciolid (liver fluke) species.

Recognition sites for nine different restriction endonucleases were mapped on rDNA genes of fasciolid species. Southern blots of digested DNA from individual worms were probed sequentially with three different probes derived from rDNA of Schistosoma mansoni and known to span between them the entire rDNA repeat unit in that species. Eighteen recognition sites were mapped for Fasciola hepatica, and seventeen for Fasciola gigantica and Fascioloides magna. Each fasciolid species had no more than two unique recognition sites, the remainder being common to one or both of the other two species. No intraspecific variation in restriction sites was noted in F. hepatica (individuals from 11 samples studied; hosts were sheep, cattle and laboratory animals; geographical origins. Australia, New Zealand, Mexico, U.K., Hungary and Spain), or in F. gigantica (two samples; Indonesia and Malaysia). Only one sample of F. magna was available. One specimen of Fasciola sp. from Japan (specific identity regarded in the literature as uncertain) yielded a restriction map identical to that of F. gigantica. Almost all recognition sites occurred in or near the putative rRNA coding regions. The non-transcribed spacer region had few or no cut sites despite the fact that this region is up to about one half of the entire repeat unit in length. Length heterogeneity was noted in the non-transcribed spacer, even within individual worms.

Animals↗
PubMed1989

[Studies on oncogene and its products of human nasopharyngeal carcinoma].

Oncogene of nasopharyngeal carcinoma (NPC) by means of external origin DNA transfection experiment and its gene products by immunohistochemical method have been studied. These DNAs were isolated from human primary poorly differentiated NPC tissues and were transfected into NIH/3T3 mouse fibroblasts to induce the foci of the morphologically transformed cells in the culture, while DNAs of normal placenta tissues failed to do so. The DNAs were extracted from the primary and secondary transformed cells to analyse human sequence with human Alu sequence probe. The human sequence has been detected in the DNAs of the primary and secondary transformed foci cells, while none of the human sequence was detected in the DNAs of the control. The results indicated that human transforming sequences had been integrated into transformed cells. The malignant properties of the transformed foci cells were evidenced by tumorigenic experiment of nude mice. The transformed foci cells were inoculated subcutaneously in the nude mice and induced fibrosarcoma in vivo. The tumorigenic rate was 87.5%. It was further demonstrated that DNAs from human NPC possessed carcinogenicity and induced malignant transformation. The primary result revealed that the transforming gene of NPC may be homologue to Ha-ras oncogene. The expression of Ha-ras gene products-p21 has been studied in human NPC tissues. The primary results showed a positive expression of p21 in human NPC tissues by immunohistochemical method. The positive rate was 90.4%.

Animals↗
PubMed1988

Effects of subchronic inhalation of D-D (1,3-dichloropropene/1,2-dichloropropane) on reproduction in male and female rats.

The effects of inhaled D-D (1,3-dichloropropene/1,2-dichloropropane) on reproduction were studied in rats of both sexes. The rats inhaled nominal concentrations of 0, 10, 30, or 90 ppm (v/v) D-D for 6 hr/day, 5 days/week for 10 weeks. Treated males of proven fertility were paired with untreated virgin females at intervals during and after exposure. Treated females were paired with untreated males immediately after the 10-week exposure period. Various aspects of reproductive performance and general toxicity were assessed. Exposure to D-D produced no adverse effects on the libido, fertility, or morphology of the reproductive tracts of rats of either sex; no treatment-related dominant lethal effect was observed in male rats. Slight reductions in body weight gains and slight increases in liver and kidney weights were observed in 90 ppm rats of both sexes.

Allyl Compounds↗
PubMed1988

Correlation between H-ras p21TLeu61 protein content and tumorigenicity of NIH3T3 cells.

We have prepared a number of NIH3T3 clonal cell lines that contain an H-ras transforming gene with an A----T transversion at the 61st codon. The clonal lines contain 1 to 3 cell equivalents of the transforming oncogene and some lines look more morphologically transformed than others. Using Y13-238, a rat monoclonal antibody that recognizes H-ras p21 but not Ki- or N-ras in rodent cells, we found that the degree of morphological change is correlated with the relative amount of transforming protein in the selected clonal lines. Nude mice were injected with cells from lines containing different amounts of the transforming protein, ranging from approximately 1 to 10 times the level of normal H-ras protein present in NIH3T3 cells. Tumors arose in all mice that received cells containing the transforming protein. Their time of appearance (tumor latency) was correlated with the number of cells injected and the amount of transforming protein present in each clonal line; however, the subsequent rate of growth and ultimate size of the tumors were similar. Thus, it appears that the transforming protein has a significant effect on some early step in tumor development. Our results also show that relatively low amounts of transforming ras protein are sufficient to cause tumorigenicity in NIH3T3 cells and that higher amounts of the transforming protein cause proportionately faster responses.

Animals↗
PubMed1987

Causal role for an activated N-ras oncogene in the induction of tumorigenicity acquired by a human cell line.

ras oncogenes have been found in approximately 15% of the human tumors analyzed. However, a causal role for these genes in the tumorigenesis of human cells has yet to be shown. Tumorigenic late-passage PA-1 human teratocarcinoma cells (E-PA-1) contain an activated N-ras gene. In this report evidence is presented that nontumorigenic early passage revertant PA-1 cells (E-PA-1) contain only the germ-line protooncogene. Introduction by gene transfer of the activated L-PA-1 oncogene induces E-PA-1 cells to form tumors, suggesting that the activated N-ras oncogene has a causal role in the tumorigenesis of these cells.

Cell Adhesion↗
PubMed1987

The nubbin sign on computed tomography and sonography.

The loss of parenchyma in the lower pole of a kidney with a duplicated collecting system may mimic a mass on urography ("the nubbin sign"). Computed tomographic findings of this entity are diagnostic. The diagnosis may be difficult to make using sonography alone.

Adult↗
PubMed1987

Habitual daily energy expenditure and activity levels of lean and adult-onset and child-onset obese women.

The energy expenditure (EE) of eight lean, eight adult-onset obese (AOO), and eight child-onset obese (COO) women was determined over three 24-h periods by the factorial method, modified by subject-keypunched and mechanically recorded activity diaries. Mean daily EE was significantly higher in the pooled obese women (2472 +/- 488 kcal) than in lean women (1979 +/- 302 kcal) due to higher energy costs of sedentary and light activity in the obese. EE during moderate-to-strenuous activity was similar between groups because lean women performed these activities more vigorously. AOO and COO differed significantly in neither mean EE nor habitual activity. Fat-free mass (FFM) was a better predictor than body weight of both mean daily EE and the energy cost of activity. These data indicate that EE is positively related to obesity. Obese women tend to limit possible EE by reducing the vigorousness of weight-supported activity.

Activities of Daily Living↗
PubMed1987

Identification of human immunodeficiency virus sequences by using in vitro enzymatic amplification and oligomer cleavage detection.

Human immunodeficiency virus (HIV) has been associated with acquired immunodeficiency syndrome and related disorders. Assays to detect antibodies to HIV proteins have been developed and used to screen sera for the identification of individuals who have been exposed to the virus. Although these serological tests have significant sensitivity and specificity for detecting exposure to the virus, they do not provide direct identification of HIV. We report here the application of recently developed nucleic acid amplification and oligonucleotide-based detection procedures for the identification of HIV sequences in established infected cell lines and in cells cultured from infected individuals.

Acquired Immunodeficiency Syndrome↗
PubMed1987

Human recipient cell for oncogene transfection studies.

We used human oncogene DNA to transform the nontumorigenic, revertant, human osteosarcoma cell line HOS TE-85 clone 5 (ATCC CRL 1543) to tumorigenicity in athymic nude mice with latency periods as short as 3 weeks. These cells were also transformed by genetic markers in genomic DNA samples. Because of their low rate of spontaneous tumor formation and the simplicity of culturing them, HOS cells provide a human cell alternative to NIH 3T3 murine fibroblasts for oncogene transfection studies.

Animals↗
PubMed1986

Temperature-sensitive splicing defect of ts110 Moloney murine sarcoma virus is virus encoded.

ts110 Moloney murine sarcoma virus (Mo-MuSV)-nonproductively infected cells (6m2) have a transformed phenotype at 28 to 33 degrees C and a normal phenotype at 39 degrees C. At temperatures permissive for transformation, 6m2 cells contain P58gag produced from the 4.0-kilobase (kb) viral RNA genome and P85gag-mos translated from a 3.5-kb spliced mRNA. At 39 degrees C, only the 4.0-kb RNA and its product P58gag are detected. Two temperature-sensitive defects have been observed in ts110-infected 6m2 cells: (i) the splicing of the 4.0-kb RNA to the 3.5-kb RNA; and (ii) the thermolability of P85gag-mos and its kinase activity relative to the wild-type revertant protein, termed P100gag-mos (R.B. Arlinghaus, J. Gen. Virol. 66:1845-1853, 1985). In the present study, we examined the mos gene products of two cell lines (204-2F6 and 204-2F8) obtained by infection of normal rat kidney cells with ts110 Mo-MuSV as a simian sarcoma-associated virus pseudotype to see whether the temperature-sensitive splicing defect could be transferred by viral infection. Southern blot analysis of these two cell lines showed that viral DNAs containing restriction fragments from cellular DNA are different from those in 6m2 cells, indicating that 204-2F6 and 204-2F8 cells have different ts110 provirus integration sites from those of 6m2 cells. Northern blots, S1 mapping analyses, and immunoprecipitation experiments showed unequivocally that the splicing defect of ts110 Mo-MuSV is virus encoded and is independent of host cell factors.

Animals↗
PubMed1986

Effects of BMY 14802, a potential antipsychotic drug, on rat brain dopaminergic function.

The potential neuroleptic alpha-(4-fluorophenyl)-4-(5-fluoro-2-pyrimidinyl)-1-piperazine-butanol HCl (BMY 14802-1) was tested for its effects on mesotelencephalic dopamine (DA) neurons in albino rats. BMY 14802-1 increased DA turnover in DA terminal regions, increased nigral DA neuronal impulse flow and blocked the behavioral stimulation and inhibition of DA neuronal impulse flow caused by DA agonists. BMY 14802-1 also increased tyrosine hydroxylase activity in vivo but did not directly affect tyrosine hydroxylase activity in vitro. In contrast to these findings, BMY 14802-1 did not cause catalepsy at any dose and reversed catalepsy produced by haloperidol. BMY 14802-1 did not block DA autoreceptors on either DA neuron soma/dendrites or on striatal nerve terminals, as assessed by inhibition of DA neuronal impulse flow by microiontophoresed DA and by inhibition of tyrosine hydroxylase activity by apomorphine, respectively. BMY 14802-1 had very low affinity for striatal D-2 receptors (IC50 greater than 10(-5) M) as determined by displacement of [3H]spiperone binding in vitro. Finally, BMY 14802-1 increased impulse flow of nigral DA neurons after pretreatment with haloperidol but had no effect on impulse flow when microiontophoresed directly onto DA neurons. It is concluded that BMY 14802-1 blocked DA-mediated effects in the mesostriatal and mesocortical/limbic systems through a non-DA receptor mechanism. BMY 14802-1 has potential as a neuroleptic with little indication of extrapyramidal motor effects.

3,4-Dihydroxyphenylacetic Acid↗
PubMed1984

Evidence for an increased risk for hypertension with centrally located body fat and the effect of race and sex on this risk.

Data from the First Health and Nutrition Examination Survey (HANES), 1971-1974, were used to examine the relationship between blood pressure and the distribution of subcutaneous body fat in 5506 survey participants, ages 30-59. Triceps and subscapular skinfolds were used as approximations of peripheral and centrally located body fat. The effects of race, sex and age on the obesity-blood pressure relationship were analyzed. Subscapular skinfold was the better predictor of both systolic and diastolic blood pressure in each race-sex group, sharing all of the association of triceps with blood pressure and having significant predictive power unshared by triceps. The slopes of regression of subscapular skinfolds with systolic blood pressure for each race-sex group were not significantly different. A 1 mm increase in skinfold thickness increased the predicted mean systolic blood pressure by 0.63 +/- 0.03 mmHg (F = 519). Mean diastolic blood pressure rose 0.43 +/- 0.02 mmHg per unit increase of skinfold in whites (F = 549), and 0.14 +/- 0.04 mmHg less in blacks (F = 13), indicating a significant racial difference. Age and subscapular skinfold contributed independently to the variability in blood pressure in each race-sex group. These results demonstrate that the blood pressure of middle-aged Americans is more directly associated with centrally deposited body fat. This finding is true across race and sex groups, and is independent of age.

Adult↗