Lactoferrin is a marker for prolactin response in mouse mammary explants

We recorded a bioassay for prolactin using densitometric analysis on polyacrylamide gels of caseins produced by mammary explants in vitro. A protein which also increased in the presence of increasing amounts of prolactin in the medium has now been identified. Its migration in several electrophoretic systems is the same as that of a whey protein of mouse milk, lactoferrin. It is an iron-binding glycoprotein with a molecular weight by SDS gel electrophoresis equal to mouse, human and bovine lactoferrin. It gives a precipitin reaction in an immunodiffusion system with monospecific antiserum raised in rabbits against mouse lactoferrin.

Chemotherapy of head and neck cancer

Chemotherapy has traditionally been relegated to a late palliative role in the management of head and neck cancer. For advanced disease in patients previously treated with surgery or radiation therapy, methotrexate, which has a response rate of approximately 50%, is the best single agent available. Other orally or systemically administered single agents--such as bleomycin, adriamycin, hydroxyurea, and cis-platinum--produce responses less frequently than methotrexate. Intraarterial chemotherapy with single-agent methotrexate or with combinations--including methotrexate, vinblastine sulfate (Velban), cyclophosphamide (Cytoxan), and 5-fluorouracil (5-FU)--can match the response rate of systemic methotrexate, but all require inpatient treatment and significant technical expertise. Programs utilizing chemotherapeutic combinations have not produced remission rates or durations of remission greater than those achieved with methotrexate alone. Chemotherapy has also been used in combination with other modalities. In two studies, chemotherapy combined with irradiation produced improvement in median or overall survival in comparison to irradiation alone. Many similar studies have been negative. Recent trials of chemotherapy used preoperatively in the treatment of head and neck cancer have not yielded decreased recurrence rates or increased overall survival rates in comparison to surgery alone, but they do appear to have prolonged the disease-free interval following definitive surgery.

Evidence for the involvement of superoxide in vitamin K-dependent carboxylation of glutamic acid residues of prothrombin

The formation of vitamin K epoxide and the vitamin K-dependent carboxylation of glutamic acid residues present in synthetic substrates and decarboxyprothrombin are both inhibited by superoxide dismutase. Catalase only inhibits the generation of vitamin K epoxide, suggesting that the carboxylation and epoxidation reactions are not inter-dependent.

Dioxygen and the vitamin K-dependent synthesis of prothrombin

It has been shown that bovine erythrocyte superoxide dismutase inhibits the gamma-carboxylation of glutamyl residues in the precursor of prothrombin and in a related synthetic peptide by a vitamin K-dependent rat liver microsomal carboxylase. In the same conditions a simple copper(II) tyrosinyl complex also inhibits the carobxylation. The formation of the vitamin K epoxide by the same systems is inhibited by both superoxide dismutase and catalase. It is suggested that the formation of the epoxide is a process distinct from carboxylation, representing perhaps a protective mechanism against the superoxide ion, or species derived therefrom, generated by the reaction of reduced vitamin K with dioxygen. Furthermore, the possibility that the carboxylating species is formed by the reaction of the superoxide ion, or species derived therefrom, with carbon dioxide, is proposed.

Bioassay for prolactin: densitometric analysis on polyacrylamide gels of milk protein production by mammary explants in vitro

Mammary explants from mice in midpregnancy cultured in a synthetic medium containing insulin and hydrocortisone respond to the addition of prolactin by the synthesis of milk proteins. The secretory response in alveolar lumina has served as a histologic endpoint in a sensitive bioassay for prolactin developed by Kleinberg and Frantz (J Clin Invest 50: 1557, 1971). This report demonstrates that the quantitative densitometric analysis of stained milk proteins (caseins) made in response to prolactin is a useful modification of that bioassay. Electrophoretic analysis of the proteins extracted from the explants permits a quantitative estimate of casein content. The amount of casein present after 5 days of incubation was found to be a measure of the prolactin concentration in the medium. No radioactive isotopes are used. The use of electrophoretic analysis has practical advantages over the histologic scoring used earlier, and has approximately the same range of sensitivity.

Multiple copies of human adenovirus 12 genomes are integrated in virus-induced hamster tumors

Tumors induced in hamsters by highly oncogenic human adenovirus 12 contain multiple copies of 90 to 100% of the viral genome in an integrated form.

Plasma adriamycin and daunorubicin levels by fluorescence and radioimmunoassay

In 38 adriamycin experiments and 4 daunorubicin experiments, radioimmunoassay readily and reproducibly detects and estimates these drugs and immunologically similar metabolites in patients' plasma and urine to at least 120 hr after dosing without interference by concurrent medication. The plasma drug decay follows first-order kinetics in a triphasic pattern. Radioimmunoassay and fluorescence assay show similar decay up to 4 hr but diverge at that point with the fluorescence assay yielding higher values. Pharmocokinetic differences are amplified in patients with liver dysfunction and may be caused by fluorescent drug metabolites not sensitive to radioimmunoassay or nonspecific fluorescent materials. The radioimmunoassay offers the capability to measure adriamycin and daunorubicin in clinical settings in which fluorescence assay is not available.

Molecular weights of three mouse milk caseins by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and kappa-like characteristics of a fourth casein

Caseins of mouse milk are phosphoproteins which precipitate at pH 4.6, stain blue with "Stains-all," and stain red with "Stains-all" following alkaline phosphatase digestion. Four caseins were separated electrophoretically in sodium dodecyl sulfate-polyacrylamide gels varying from 8.5 to 15% acrylamide. Molecular weights for three of these proteins were 43,200, 27,700, and 25,900. The molecular weights determined for bovine alphas1 and beta caseins by this method were similar to those previously obtained by other methods. A fourth mouse casein contained carbohydrate, phosphorus, and sialic acid. This protein was rennin-sensitive and behaved anomalously on sodium dodecyl sulfate polyacrylamide gels, as did bovine kappa-casein. Because of similarities with bovine kappa-casein, it was designated with "kappa-casein" of mouse milk.

Methotrexate pneumonitis induced by intrathecal methotrexate therapy: a case report with pharmacokinetic data

A patient with adenocarcinoma of the breast metastatic to the leptomeninges was treated with 10 doses of intrathecal methotrexate (MTX) administered at intervals of 2 days. Following these treatments she developed fever, hypoxemia, and bilateral pulmonary infiltrates without documented pulmonary infection. Autopsy findings were consistent with the pneumonitis that has been associated with intermittent oral, intramuscular, and intravenous MTX therapy. It is suggested that this patient's pulmonary process represented MTX pneumonitis following intrathecal MTX. Cerebrospinal fluid and serum MTX concentrations determined retrospectively on frozen samples reflect an atypically rapid transport of MTX from this patient's cerebrospinal fluid to a slowly decaying systemic pool. Because of this, serum MTX levels probably exceeded 10-8M during the entire 20-day course of therapy, thus exposing the pulmonary parenchyma to significant drug concentrations for a prolonged interval. It is suggested that these unfavorable pharmacokinetics may have contributed to this patient's susceptibility to MTX pneumonitis.

A unique pattern of integrated viral genes in hamster cells transformed by highly oncogenic human adenovirus 12

We have analyzed the viral DNA sequences persisting in HE C19, a clonal line of hamster embryo cells transformed in vitro by human adenovirus 12 (Ad 12), a member of highly oncogenic group A. Saturation-hybridization of in vitro labeled Ad 12 DNA (2-4 x 10(8) cpm/mug) with HE C19 DNA showed that 93-100% of viral DNA sequences are present in the transformed cell. Reassociation of Ad 12 32P-DNA in the presence of HE C19 DNA detected 8 viral genome equivalents per diploid quantity of cell DNA. REannealing each of the six Ad 12 EcoRl restriction DNA fragments with HE C19 DNA indicated that the sequences of each fragment are present in near equimolar quantities, 8-10.5 copies per cell. HE C19 DNA "networks" were prepared and shown to contain the same viral DNA sequences and in the same amounts as present in unfractionated transformed cell DNA; these data provide the first direct evidence that human adenovirus genes are covalently linked to cellular DNA. The presence of most, if not all, of the viral genes was demonstrated also in the Ad 12 hamster tumor cell line, HT-2. The pattern of integrated viral genes in these nonpermissive hamster cells transformed by Ad 12 is different from that described for cells transformed by group C and B human adenoviruses and for SV40.

Characterization of major milk proteins from BALB/c and C3H mice

Milk proteins from BALB/c and C3H mice were characterized with respect to their electrophoretic migration in polyacrylamide gels under alkaline and acid conditions. The major casein and whey proteins from each strain migrated similarly under the conditions employed. Phosphoproteins were identified by staining with "Stains-all" and by changes in electrophoretic mobility and staining induced by prior treatment with phosphatase. Sialic acid-rich glycoproteins were identified by staining with periodic acid-Schiff and with "Stains-all" by prior treatment with neuraminidase to identify sialic acid as the acidic portion of the molecule. The two major whey proteins were characterized further by their migration in sodium dodecyl sulfate gels. One protein had the same mobility as mouse serum albumin. The other protein migrated with a mobility similar to that of bovine alpha-lactalbumin. The identity of the former protein was confirmed by its reaction with goat anti-mouse serum albumin in an immunodiffusion procedure, and the latter protein by its B protein activity in the lactose synthetase assay.

Inhibition of purified DNA polymerase of RNA tumor viruses by fluoranthene derivatives and analogues of tilorone hydrochloride

At concentrations of 7 times 10(-6) to 7 times 10(-5) M, derivatives consisting of the polycylic ring structures fluoranthene, fluorenone, fluorene, anthraquinone, xanthenone, and dibenzofuran with appropriate amine side chains inhibited by over 90% the purified RNA-directed DNA polymerase of avian myeloblastosis virus acting on poly(deoxyadenylate-deoxythymidylate) [poly(dA-dT)]. Of these, only the fluoranthene derivatives were strong inhibitors of the viral DNA polymerase directed by polyadenylate-oligodeoxythymidylate [poly(A)-(dT)12-18]. Low levels of fluoranthene derivatives (1 times 10(-5) M) also strongly inhibited polymerase with polyinosinate-oligodeoxycytidylate [poly(I)-(dC)12-18], activated calf thymus DNA, and viral 70S RNA as templates, but not with polycytidylate-oligodeoxyguanylate as template. A comparison of the activity of 11 fluoranthene derivatives with different side chains showed that the structure of the amine side chain influenced both the extent of antipolymerase activity with a given template and the relative inhibition with different synthetic DNA and RNA templates. The naturally occurring polyamines, spermine, spermidine, and putrescine, did not inhibit the activity of the viral DNA polymerase. Studies on the mechanism of action indicated that the synthetic derivatives inhibited polymerase activity by binding to the template and not to the enzyme: 1) inhibition by fluoranthene derivatives was overcome by the addition of excess template including poly(dA-dT), poly(A)-(dT)12-18, poly(I)-(dC)12-18, viral 70S RNA, and activated calf thymus DNA; 2) the degree of inhibition by fluoranthene derivatives was unaffected by the addition of the creased viral DNA polymerase; 3) with the same template, Escherichia coli DNA-directed RNA polymerase and the viral RNA-directed DNA polymerase were inhibited to about the same extent; and 4) the derivatives formed a complex with DNA, poly(I), and poly(A) that was stable to exclusion chromatography on Sephadex G-100. Several derivatives also had biologic activity, since they blocked the ability of the murine sarcoma virus to transform cells.

Simultaneous differential staining of nucleic acids, proteins, conjugated proteins and polar lipids by a cationic carbocyanine dye

The multiple interactions of the cationic carbocyanine dye, 1-ethyl-naptho-[1,2d]thiazolin-2-ylidene)-2-methylpropenyl]naptho[1,2d]thiazolium bromide, 'Stains-described. Many of these substances could be distinguished from one another on the basis of color in conjunction with chemical and enzymatic digestions. Further studies with this dye have shown that under certain conditions polar lipids as well may be distinguished from these substances. Stains-all has a highly sensitive metachromatic reaction for the presence of polar lipids. It is possible to detect the lipids in large part because they are green and contrast with a red- or pink-stained protein background and with the blue-purple of nuclei or cartilage. Where other green substances occur as in sialoglycoproteins of mucous or membranes, the lipids can be distinguished because they are extracted by chloroform-methanol (2:1) or pyridine.

Simultaneous differential staining by a cationic carbocyanine dye of nucleic acids, proteins and conjugated proteins. I. Phosphoproteins

The cationic carbocyanine dye l-ethyl-2-[3-(l-ethylnaphtho[l,2d]thiazolin-2-ylidene)-2-methylpropenyl]-naphtho[1,2d]thiazolium bromide interacts in different ways with several classes of polymeric anions in solution. This results in changes in absorption maxima which differ from the absorption maximum of the dye solution. The multiple interactions with macromolecules were demonstrated in histologic sections. Under appropriate electrolyte, dye and hydrogen ion concentrations, nucleic acids, proteins and conjugated proteins were distinguished from each other by color. The phosphoproteins stained blue, proteins red, nucleic acids purple and mucoproteins and mucopolysaccharides various colors. Further discrimination was obtained by chemical procedures and enzymatic digestions. Secretions in alveolar and ductal lumina in the mammary glands of pregnant mice were shown to stain differentially from the other macromolecules. It is inferred on the basis of enzymatic and chemical procedures that the secretions stained blue because of their phosphoprotein content. Conventional staining procedures did not allow this distinction to be made.

Simultaneous differential staining by a cationic carbocyanine dye of nucleic acids, proteins and conjugated proteins. II. Carbohydrate and sulfated carbohydrate-containing proteins

The cationic carbocyanine dye l-ethyl-2-[3-(l-ethylnaphtho[l,2d]thiazolin-2-ylidene)-2-methylprolpenyl]-naphtho[1, 2d]thiazolium bromide stains several classes of macromolecules differentially in histologic sections. Most proteins are red at pH 4.3 and pink or unstained at pH 2.8. The caseins are blue at pH 4.3 and unstained at pH 2.8. Nuclei stain purple, mast cells stain red-purple, cartilage stains purple and mucoproteins stain blue-green at both hydrogen ion concentrations. The nature of some of the macromolecules involved in these color reactions has been determined by the use of chemical and enzymatic procedures and by staining films of glycosaminoglycuronoglycans, proteins and conjugated proteins. The method requires less than 1 hr staining time for most tissues; the stain is stable when kept in the dark and has the advantage of distinguishing several macromolecules in tissues simultaneously. The simplicity of the method and the ability to discriminate classes of macromolecules in tissues should make this stain valuable in pathologic diagnosis.

Characteristics of physicians interested in psychiatric education

720 primary (nonpsychiatrist) physicians responded to a mail distributed questionnaire investigating their attitudes to and practices with psychiatric education, psychiatrists and emotionally disturbed patients. Respondents were divided into two groups on the basis of whether or not they had attended postgraduate courses in psychiatry. Outstanding characteristics of the physicians who had taken courses compared to those who had not were: 1) a higher percentage in general practice than in a specialty, 2) greater confidence in their own psychiatric diagnostic and therapeutic skills, 3) higher estimates of psychiatric disorders in their practices, 4) more willingness to treat emotionally disturbed patients, including aftercare patients, 5) more competent use of psychoactive drugs for depression and schizophrenia, 6) greater interest in psychiatry, 7) stronger subjective needs for help with the management of their disturbed patients, and 8) higher frequency of personal psychotherapy. The two groups did not differ in: 1) evaluations of their previous educational experiences in psychiatry, 2) the hours per week devoted to medical practice, or the number of patients seen per day, 3) indications for intervention or preferred modes of treatment with psychiatric cases, 4) attitudes towards the usefulness of psychiatry, 5) frequency of making psychiatric referrals, and 6) skill with psychoactive drugs for anxiety.