Biomedical subjects

D Ring

Publications and source records attributed to D Ring.

11 recordsLinked to original sources

PubMed1989

Differential induction by interferons of major histocompatibility complex-encoded and non-major histocompatibility complex-encoded antigens in human breast and ovarian carcinoma cell lines.

Treatment of cancer cells with interferons can modulate expression of cell surface antigens, particularly those of the major histocompatibility complex (MHC). To examine the effect of recombinant gamma- and alpha-interferons on expression of non-MHC antigens, murine monoclonal antibodies have been used to quantitate 14 distinct tumor-associated cell surface antigens from five breast cancer cell lines and five ovarian cancer cell lines using a live cell radioimmunoassay. Both Class I and Class II MHC antigens could be augmented or induced with gamma-interferon. Significantly increased expression of MHC antigens was observed in nine of 10 cell lines with induction indices as high as 11-fold. When 17 non-MHC epitopes were measured on 10 cell lines, minimal (1.3-2.7-fold) induction was observed in 10 of the 170 instances evaluated. Expression of only two epitopes, 2G3 and 735B11, was increased on more than one cell line. On six cell lines expression of non-MHC epitopes could not be increased. Consequently, among many different cell surface determinants, interferons produced a highly selective augmentation or induction of MHC antigens, whereas augmentation or induction of other tumor-associated antigens was apparently restricted to a few epitopes.

Antigens, Neoplasm↗

PubMed1989

Heterogeneity of antigen expression in benign and malignant breast and ovarian epithelial cells.

Expression of II distinct antigen families has been studied in normal and malignant epithelial cells from breast and ovary by avidin-biotin immunoperoxidase staining of frozen tissue sections. Each of the antigens was expressed in a fraction of the normal and malignant breast tissues from different individuals. Among breast and ovarian cancers, a similar fraction of tumors expressed each of the determinants. An epitope on a 42-kDa glycoprotein was expressed significantly more often by ovarian carcinomas than by benign ovarian epithelium. Several determinants on 66-, 240-kDa or high-molecular-weight proteins or glycoproteins were expressed significantly more often on benign breast epithelium than on normal ovarian epithelium. Substantial heterogeneity in antigen expression was observed among different tumor specimens. Each of 14 epithelial ovarian cancers expressed a distinctive combination of antigens. Among 18 breast cancers, 16 distinct antigenic phenotypes were observed. Interestingly, comparable heterogeneity was observed in the expression of epitopes on benign breast and ovarian epithelium, compatible with the possibility that the monoclonal reagents recognized polymorphic determinants. Substantial variations in antigen expression were also observed among cells within each neoplasm. However, when antibodies against 5 different determinants were used in combination, a majority of cells could be stained intensely in all 13 breast carcinomas tested and more than 95% of tumor cells could be stained in 10 of the 13.

Antigens, Neoplasm↗

PubMed1989

[Rectal examination during labor--tradition or compelling necessity?].

6,639 consecutive deliveries are followed up with respect to the course of puerperium. All these patients were examined during delivery vaginally. Febrile temperatures sub partu were to be stated in 1.1% and post partum in 2.0%. Subfebrile temperatures within the first 7 days of puerperium were to be seen in 7.0%, neonatal infections in 0.5%. The pro and contra of vaginal versus rectal investigation are discussed. The use of an emulsion containing chlorhexidine an antiseptic gliding substance is recommended for obstetrical examinations before and during labour.

Bacterial Infections↗

PubMed1989

[Ectopic pregnancy--still a challenge in gynecology. A contribution to diagnosis and therapy].

The diagnostic and therapeutic management in 80 cases with ectopic pregnancy is analysed. Only in 36 cases (45%) there was an accordance of installation diagnosis with the intraoperative status. 44 patients (55%) were suspicious to suffer from acute pelvic inflammatory disease, abortion or irregular uterine bleedings. Only in 28 cases (35%) the clinical symptomatology was so characteristic for ectopic pregnancy that operation had been performed without any other diagnostic procedures. In 34 cases (43%) a laparoscopy was necessary to get the correct diagnosis. In all the other 18 patients (22%) the indication for operation was made by punction of the cul-de-sac, curettage, and/or ultrasound. Because of an increased blood loss more than 500 ml an intra- or postoperative blood transfusion was necessary in about 1/3 of all treated patients. In 32% it was possible to preserve the fallopian tube. The corresponding operative procedure consisted of salpingotomy and manual expression of tubal pregnancy. Local vasoconstrictive acting substances are recommended. If there are hints at an ectopic pregnancy by histologic examination of tissue got by curettage quick and well-organized management is necessary to use the possibility of conservative operation-procedures. Histologic examination of all abortion tissue is requested.

Adolescent↗

PubMed1989

Effector characteristics of the IgG3 murine monoclonal antibody 113F1.

Successful immunotherapy with unconjugated murine monoclonal antibodies (MAbs) is likely to require antibodies with potent effector characteristics such as antibody-dependent cellular cytotoxicity (ADCC). The newly developed IgG3 isotype antibody, 113F1, binds to a target antigen present in high copy number on SK-Br-3 cell surfaces. 113F1 does not appear to participate in complement-mediated cytotoxicity, but is a potent mediator of ADCC by human monocytes directed against a variety of malignant cell lines expressing 113F1's target antigen. Although recombinant interleukin-2 (rIL-2) promotes nonspecific monocyte cytotoxicity, preincubation with this cytokine has no effect on monocyte ADCC in our system. 113F1 promotes ADCC by nonadherent cells expressing lymphokine-activated killer (LAK) activity following incubation of these cells in rIL-2. These latter effects are abrogated by Fc receptor blockade prior to addition of 113F1. 113F1 is a more potent mediator of ADCC by monocytes or LAK cells than is 17-1A, an extensively tested unconjugated murine IgG2a isotope MAb. These data suggest that unconjugated 113F1 MAb immunotherapy trials should investigate treatment with the MAb alone. In addition, 113F1 could be administered with rIL-2, either alone or supplemented with infusions of autologous LAK cells.

Animals↗

PubMed1988

[Preventive use of iron in pregnancy--a luxury or a necessity?].

In an exploratory study 128 healthy gravidae were given 0.114 g of iron daily from the 14th week of pregnancy until birth. Hematologically and clinically important parameters during pregnancy, birth, and puerperium were compared with an untreated control group of 115 gravidae. Following iron prophylaxis, hemoglobin concentration, hematocrit, and erythrocyte count were significantly higher at the time of birth; however, obstetrically significant parameters were unaffected. In view of the low incidence of anaemia during pregnancy and birth, as well as the completeness of the prenatal care system, general iron prophylaxis is unnecessary. High-risk pregnancies are an exception to this rule. The high incidence of anaemia early in puerperium justifies adequate, i.e., high-dose, oral iron therapy from the first day of the first week of confinement on wards.

Anemia, Hypochromic↗

PubMed1988

[The use of a double balloon catheter in the topical extra-amniotic administration of prostaglandin F2alpha gel in indicated labor induction and cervix incompetence].

Using a self-made double-balloon-catheter the instillation of 2.5 mg Prostaglandin F2 alpha into the extraovular chorio-decidual space was down 46 times in 42 late pregnant women. The indication was the unripe cervix uteri in case of urgent parturition. This method is more effective than the pericervical and endocervical application, respectively. Under continuous supervision using external CTG there were neither complications in fetus nor in the mother.

Catheterization↗

PubMed1988

[Postpartum curettage--is it always indicated?].

Within five years (1982-1986) there were in the Dept. Obstet. Gynec., Main Hospital of Suhl 382 curettements after 7,462 term deriveries (greater than 37. week of pregnancy). This is a frequency of 5.2%. Only in 25% there was a histologic confirmation of placental tissue. Discussion about possibilities to reduce the frequency of such curettements post partum without neglecting necessary interferences.

Chorionic Villi↗

PubMed1985

Evaluation of monoclonal antibodies for the development of breast cancer immunotoxins.

Eighty-five antibodies recognizing breast cancer-selective antigens were conjugated to ricin toxin A-chain using a disulfide linkage. The cytotoxicities of the resulting immunotoxins were determined on breast cancer cells and normal human fibroblasts. Twenty-four antibodies formed immunotoxins that were toxic to at least one breast cancer cell line at concentrations of 10 nM or less but were nontoxic to human fibroblast lines used as negative controls. Some of the breast tumor-selective immunotoxins were as toxic as a conjugate between monoclonal anti-transferrin receptor and ricin toxin A-chain (50% inhibition of cellular protein synthesis at approximately 0.1 nM). Another set of four immunotoxins were indiscriminately toxic to human breast tumor cell lines, two human fibroblast cell lines, and a human lymphoblastoid line. Several of the antibodies the toxin conjugates of which specifically killed breast cancer cell lines may be useful in cancer therapy, since they show a wide range of binding to individual breast tumors and cell lines and a limited range of binding to normal tissue types.

Antibodies, Monoclonal↗

PubMed1979

Chemical cross-linking of H1 histone to the nucleosomal histones.

When whole steer kidney nuclei were treated with dimethyl-3,3'-dithiobisproprionimidate, N,N'-bis(2-carboxyimidomethyl) tartaramide dimethyl ester, or 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide under approximately physiological ionic conditions, H1 histone was cross-linked to each of the four histones in the nucleosome core. The carbodiimide reagent, which introduces no atoms between the amino acid side chains being joined, seemed to give the same result as did the longer di-imidate cross-linking reagents. When conditions were optimized for the production of of H1-containing dimers, the total yield of H1-core histone heterodimers was nearly equal to the yield of H1 homodimers. Naturally occurring H1 dimers and cross-linked heterodimers of high mobility group proteins 14 and 17 with H1 and core histones were also observed.

Animals↗

PubMed1972

Prebiotic synthesis of hydrophobic and protein amino acids.

The formation of amino acids by the action of electric discharges on a mixture of methane, nitrogen, and water with traces of ammonia was studied in detail. The presence of glycine, alanine, alpha-amino-n-butyric acid, alpha-aminoisobutyric acid, valine, norvaline, isovaline, leucine, isoleucine, alloisoleucine, norleucine, proline, aspartic acid, glutamic acid, serine, threonine, allothreonine, alpha-hydroxy-gamma-aminobutyric acid, and alpha,gamma-diaminobutyric acid was confirmed by ion-exchange chromatography and gas chromatography-mass spectrometry. All of the primary alpha-amino acids found in the Murchison Meteorite have been synthesized by this electric discharge experiment.

Alanine↗