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T Gregory

Publications and source records attributed to T Gregory.

48 records · Page 3Linked to original sources
PubMed1987

Characterization of recombinant human factor VIII.

Recently, complete human factor VIII DNA clones have been obtained and subsequently expressed in baby hamster kidney cells (Wood, W. I., Capon, D. J., Simonsen, C. C., Eaton, D. L., Gitschier, J., Keyt, B., Seeburg, P. H., Smith, D. H., Hollingshead, P., Wion, K. L., Delwart, E., Tuddenham, E. G. D., Vehar, G. A., and Lawn, R. M. (1984) Nature 312, 330-337). The recombinant factor VIII (rVIII) protein secreted from these cells has now been purified allowing its structural analysis and comparison to plasma-derived factor VIII (pdVIII). Analysis of purified rVIII by sodium dodecyl sulfate-polyacrylamide gel electrophoresis shows that it consists of multiple polypeptides with relative mobilities (Mr) ranging from 80,000-210,000. The same pattern of polypeptides is also observed for pdVIII resolved by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The proteins associated with rVIII are recognized by pdVIII antibodies in a Western blot. When rVIII and pdVIII are subjected to isoelectric focusing they are resolved into a similar pattern of protein bands. Thrombin, factor Xa, and activated protein C, which modulate factor VIII activity by proteolysis, process rVIII in the same manner they do pdVIII. As is the case for pdVIII, thrombin activation of rVIII coagulant activity correlates with the generation of subunits with Mr of 73,000, 50,000 and 43,000. These subunits appear to form a metal-(perhaps Ca2+) linked complex. EDTA inactivates thrombin-activated rVIII and pdVIII, with the activity being regenerated after the addition of a molar excess of MnCl2. The results suggest that rVIII is structurally and functionally very similar to pdVIII.

Animals↗
PubMed1987

De novo X;Y translocation associated with imperforate anus and retinal pigmentary abnormalities.

Cytogenetically detectable translocations of Y chromosome material onto the distal short arm of an X chromosome are rare and result in a variable and poorly defined phenotype of short stature and short limbs occasionally associated with mental retardation. We report on a patient with a de novo 46,X,t(X;Y)(p22;q11) chromosome constitution who has additional features not previously described with this chromosome abnormality, including abnormal retinal pigmentation, imperforate anus, and hydronephrosis. Our patient extends the phenotype associated with X;Y translocations, raising new considerations for the clinical management and genetic counseling of such patients and their families.

Abnormalities, Multiple↗
PubMed1987

T-cell responses to human immunodeficiency virus (HIV) and its recombinant antigens in HIV-infected chimpanzees.

Peripheral blood lymphocytes from chimpanzees infected for 3 months to more than 3 years with human immunodeficiency virus (HIV) had normal T-cell proliferative responses after stimulation with a variety of recall antigens and mitogens, indicating that HIV infection does not cause detectable immunological impairment in chimpanzees. This finding contrasts with that obtained in HIV-infected humans, who often have impaired T-cell reactivity. Peripheral blood lymphocytes from most HIV-infected chimpanzees that were studied also had strong proliferative responses to purified HIV as well as to HIV envelope glycoproteins isolated from the virus, to recombinant HIV envelope glycoproteins gp120 and gp41, and to HIV gag protein p24. The HIV-specific T-cell responses in HIV-infected chimpanzees may contribute to prevention of the development of acquired immunodeficiency syndrome in this species.

Acquired Immunodeficiency Syndrome↗
PubMed1985

Protection from genital herpes simplex virus type 2 infection by vaccination with cloned type 1 glycoprotein D.

Guinea pigs were vaccinated with truncated herpes simplex virus type-1 (HSV-1) glycoprotein D produced in the genetically engineered mammalian cell line gD10.2. Vaccinated animals formed antibodies that neutralized both HSV-1 and herpes simplex virus type 2 (HSV-2) in an in vitro neutralization assay. Vaccinated animals were challenged with HSV-2 by intravaginal infection. Animals that received the immunogen in Freund's complete adjuvant were completely protected from the clinical manifestations of genital HSV-2 infection. Animals that received the immunogen incorporated in alum adjuvants were partly protected from clinical disease; the infections that did develop were significantly less severe than those that occurred in control animals injected with adjuvant alone. The results demonstrate that immunization with a purified viral protein can provide significant protection against primary genital infection by HSV-2 in guinea pigs.

Adjuvants, Immunologic↗
PubMed1984

Location of the retinoblastoma susceptibility gene(s) and the human esterase D locus.

Retinoblastoma occurs with increased frequency in children born with a deletion of the long arm of chromosome 13. Recent reviews have noted that the region 13q14 is consistently deleted in documented cases. Prometaphase and late prophase banding allowed Yunis and Ramsay to determine that a deletion in one patient included the sub-bands q14 . 12, q14 . 13, and q14 . 2, and a portion of q14 . 11 and q14 . 3. We report the results of similar cytogenetic techniques applied in the case of a 26 month old Caucasian female with unilateral retinoblastoma, moderate developmental delay, and subtle dysmorphology. Prometaphase banding of cultured skin fibroblasts revealed the karyotype: mos46,XX/46,XX,del(13)(q13 . 1q14 . 11). Only the sub-band q14 . 11 is deleted in both our patient and that of Yunis and Ramsay. The results are consistent with the localisation of the retinoblastoma susceptibility gene(s) in the sub-band 13q14 . 11. Electrophoretic analysis and activity assays of red blood cell esterase D are consistent with hemizygous expression of that marker in our proband. Comparison with published esterase D analyses in families with retinoblastoma permits the assignment of the esterase D locus to that same sub-band, 13q14 . 11.

Carboxylesterase↗
PubMed1984

Use of artificial streams for toxicological research.

A review of the literature pertaining to the use of artificial streams as research tools in both toxicant and nontoxicant studies was conducted. This document summarizes that review and provides an assessment of the value of artificial streams in toxicological research. Descriptions are presented of the major types of artificial streams including considerations for the physical design of those streams based on their intended use. Research representative of nontoxicant behavioral, productivity, and trophic relationship studies is summarized to provide a background for the more in-depth discourse on toxicant research. Toxicant research is reviewed in relation to environmental factors such as physical type of artificial stream, light, water, and substrate and experimental conditions including biota tested, method of biota introduction, measured parameters, and toxicant. Comparisons and assessment are presented concerning the use of the appropriate artificial system for addressing various types of toxicant research emphasizing simple vs. complex systems.

Animals↗
PubMed1979

Studies of 16-androstenes in an infant with virilizing adrenal carcinoma.

An 18-month-old girl with virilization was found to have an encapsulated right adrenal carcinoma (2 x3 cm) with great variation in nuclear size, frequent mitoses, and possible blood vessel invasion. Preoperative urinary excretions of 17-ketosteroids, androsterone, etiocholanolone, dehydroepiandrosterone, testosterone, pregnanetriol, 3alpha-androstenol, and 3 beta-androstadienol were elevated; all showed a noticeable decrease postoperatively. Cortisol acetate, given preoperatively, produced a definite decrease in the urinary excretion of 17-ketosteroids and dehydroepiandrosterone; administration of corticotropin resulted in an increase in levels of urinary 17-ketosteroids, 17-hydroxycorticosteroids, and pregnanetriol. Urinary testosterone and 3beta-androstadienol may have diagnostic value since neither was suppressed by cortisol therapy. The behavior of both 3alpha-androstenol and 3beta-androstadienol in this study suggests that they are of adrenal origin.

17-Hydroxycorticosteroids↗
PubMed1976

Hypertensive virilizing adrenal hyperplasia with minimal impairment of synthetic route to cortisol.

One of the first described cases of hypertensive virilizing adrenal hyperplasia (VAH) (Pediatrics 8: 805, 1951) has been followed from age 2 1/2 until age 26. Blood pressure as an infant was 150/90, and at age 25 was 220/160. During childhood the patient was lost to follow-up for prolonged periods, and received no therapy from age 20 to 25. At this time 24 h urinary excretion of 17-ketosteroids was 89 mg; tetrahydro 11-deoxycortisol (tetrahydro S), 47 mg and pregnanetriol 5.7 mg. Hourly measurements of several plasma steroids utilizing sephadex LH 20 chromatography and competitive protein binding were made during 24 h; concentration ranges were made during 24 h; concentration ranges were as follows (mug/100 ml): 11-deoxycortisol 8-40; cortisol 0-48; corticosterone 0-15; deoxycorticosterone 1-18. Plasma cortisol, especially showed a significiant morning impairment, but reached normal and even markedly elevated levels during the day and early evening. Urinary cyclic AMP per 24 h ranged from 5.3 to 11.6 n mol/mg creatinine before therapy, and was 1.9 n mol after therapy. The results suggest either the formation of an alternate pathway to cortisol synthesis, or the existence of a form of VAH with two independent 11-B hydroxylating systems, exhibiting only minimal impairment of the synthetic route to cortisol. The latter would support the presence of two independent 11-B hydroxylating systems in the normal human adrenal. This has been suggested by Zachmann et al. (J Clin Endocrinol Metab 33: 501, 1971) to be true in infancy. Our observations on an adult indicate that these two systems may not be transitory, but persist into adulthood.

Adrenocortical Hyperfunction↗