Role of oxytocin in the modulation of ACTH release in women

To determine if oxytocin (OT) may have a modulatory role on corticotropin-releasing factor (CRF) and vasopressin (AVP) mediated ACTH-cortisol release in women, serial experiments were performed in which saline, OT, AVP and CRF were administered singly or in combinations. OT administration (2 IU intravenous bolus followed by 111 mIU/min infusion for 3 h) maintained a circulating concentration of 7.7 X 10(-8) M and did not significantly influence basal, AVP or CRF-induced ACTH-cortisol release. In contrast, OT inhibited significantly the potentiating effect of AVP on CRF-stimulated ACTH-cortisol release. These findings suggest that OT and AVP may modulate, in a reciprocal fashion, the CRF-mediated ACTH release and support the contention that OT may be involved in the neuroendocrine response to stress in women.

Mitoxantrone in malignant lymphoma

Two phase II trials of mitoxantrone in refractory malignant lymphoma have been conducted. In the first of these, mitoxantrone (5 mg/m2) was given weekly for 6 weeks, and in the second, 14 mg/m2 was administered every 3 weeks. The first trial was conducted by the Southeastern Cancer Study Group (SECSG), and the second was a multicenter trial sponsored by Lederle Laboratories. Of the 80 patients entered in the SECSG trial, 47 could be evaluated for response and 43 for toxicity. Granulocyte nadirs below 1.9 X 10(9)/L were recorded in 18 patients. Four partial responses and no complete responses were obtained. These results contrast with those of the high dose study in which 41 patients were entered, and 28 of these were evaluated for response. Responses were obtained in 15 patients (2 complete, 13 partial). Side effects on this 3 weekly dose regimen were minimal. WBC nadirs ranged from 1 to 4.3 X 10(9) cells/L (mean 2.5 X 10(9)/L). Three patients experienced mild nausea and vomiting, and two had mild alopecia. These preliminary data indicate that mitoxantrone has significant activity in malignant lymphoma. All of the responding patients had received extensive prior therapy, many of them with anthracyclines in combination or as single agents. The higher response rate to mitoxantrone given at 14 mg/m2 every 3 weeks suggests that careful consideration should be given to dose when this drug is examined further in phase III trials.

Treatment of congenital osteopetrosis with high-dose calcitriol

We administered high doses of calcitriol (up to 32 micrograms per day) to an infant with malignant osteopetrosis, in an attempt to stimulate bone resorption. The patient was placed on a low-calcium diet to prevent hypercalcemia. Measures of bone turnover increased during calcitriol therapy; hydroxyproline excretion rose from 140 to 1358 micrograms per milligram of creatinine per 24 hours, with parallel increases in the ratio of calcium to creatinine in the urine, urinary gamma-carboxyglutamic acid, serum osteocalcin, and serum alkaline phosphatase. A pretreatment bone-biopsy specimen contained no osteoclasts with ruffled borders, a feature of active osteoclasts. After 11 days of calcitriol, ruffled borders were noted. After three months, numerous osteoclasts with ruffled borders and associated bony disruption were evident. Before therapy, the patient's monocytes were incapable of in vitro bone resorption, but after calcitriol, their resorptive capacity was increased to 3.3 times control levels. These data demonstrate that calcitriol increased bone mineral and matrix turnover in our patient. However, during the three months of calcitriol therapy there was only slight clinical improvement in her severe disease. Early and sustained treatment with calcitriol may be useful in osteopetrosis.

Dextran sulphate induced arthritis in rabbits

Persistent effects of a short course of intra-articular dextran sulphate, dextrans, or chondroitin sulphate were examined in rabbit knees. Only dextran sulphate produced gross arthritis, associated with high synovial acid phosphatase and beta-glucuronidase activities. Synovial degradative capacity in synovium-cartilage cocultures was increased 2-fold by dextran sulphate and 1.5-fold by chondroitin sulphate treatments. Stimulation of cartilage breakdown in vitro paralleled the content of synovial marker enzyme at death of the animal, but the 2 responses could be dissociated.

A trypsin method for coating human red blood cells with plasma C3 and/or C4

Simple procedures are described for the production of human red blood cells coated with C3 and/or C4 by brief trypsin treatment of cell-plasma mixtures at room temperature. These cells ('EC3/4'-try) were unusual in that their agglutinability by anticomplement sera, as compared to sucrose-water RBC, was similar when tested by AutoAnalyzer but was markedly reduced in manual testing, especially against anti-C4. In spite of this, both 'EC34'-try and 'EC3'-try were found to be suitable indicator cells for determining the adequacy of anti-C3c and/or anti-C3d activities in reagents used for manual antiglobulin tests.

The detection of DNA-binding proteins by protein blotting

A method, called "protein blotting," for the detection of DNA-binding proteins is described. Proteins are separated on an SDA-polyacrylamide gel. The gel is sandwiched between 2 nitrocellulose filters and the proteins allowed to diffuse out of the gel and onto the filters. The proteins are tightly bound to each filter, producing a replica of the original gel pattern. The replica is used to detect DNA-binding proteins, RNA-binding proteins or histone-binding proteins by incubation of the filter with [32P]DNA, [125I]RNA, or [125I] histone. Evidence is also presented that specific protein-DNA interactions may be detected by this technique; under appropriate conditions, the lac repressor binds only to DNA containing the lac operator. Strategies for the detection of specific protein-DNA interactions are discussed.

C3d antiglobulin haemagglutination of human red blood cells. A demonstration of two types of cell-bound C3d by means of typsin digestion

Washed human red blood cells from blood collected in EDTA were tested by Auto-Analyzer for a percentage of maximum antiglobulin haemagglutination (AH) using monospecific antisera to human C3d and C3c. The cells from normal persons were found to be agglutinated by anti-C3d but not by anti-C3c. To a fixed dilution of antiserum, the normal C3d AH values (X +/- 2 SD) were 34 +/- 19% for adult cells (n = 29) and 14 +/- 19% for cord cells (n = 19); the difference was significant (P less than 0.0001). By pretreatment of these cells with trypsin the C3d AH was either completely abolished or markedly reduced. Its difference between the adult and cord cells was eliminated as the observed values were 4 +/- 7% and 3 +/- 4% respectively (P = 0.15). The supernatant fluid of cell-trypsin mixture, treated with trypsin inhibitors, was found to be inhibitory to C3d AH but not to C3c AH. In contrast, the AH of C3d-coated red blood cells resulting from complement fixation in vivo (ie, cold agglutinin disease) or in vitro (eg, sucrose water reaction) was resistant to trypsin treatment. The difference between the trypsin-sensitive and trypsin-resistant cell-bound C3d is postulated to be at its attachment mechanism to the cell membranes. In addition, both the advantage and limitation of using trypsinised cells for C3d antiglobulin tests are demonstrated.

A tissue culture model of cartilage breakdown in rheumatoid arthritis. III. Effects of antirheumatic drugs

The effects of hydrocortisone, indomethacin, and gold thiomalate on proteoglycan release were assessed in bovine nasal cartilage-rheumatoid synovium cocultures. Of the three agents, only hydrocortisone consistently inhibited both basal and synovium-stimulated cartilage breakdown. Hydrocortisone responsivity was a direct function of the degradative capacity of synovial specimens, and this was equally well demonstrated both in patients receiving long-term therapy and those given perioperative glucocorticoid therapy. The data are consistent with significant hydrocortisone inhibition of lysosomal enzyme-mediated degradation of cartilage.

The low ionic strength reaction of human blood: relationship between the binding of serum immunoglobulin and complement of red blood cells and surface charge of the cells

Using the sucrose haemolysis reaction of Hartmann & Jenkins (1966) as a basic model, the low ionic strength reaction (LISR) of human blood was studied to determine: (1) serum Ig uptake by RBC with saline elution and 125I-IgG uptake, and (2) complement fixation (CF) to RBC with lysis of PNH cells and C3H/C4 antiglobulin haemagglutination (AH) of normal cells. The saline eluates were found to contain IgG and IgM with traces of IgA; their pH optima for the uptake by RBC were 6.0 +/- 0.5, 5.5 +/- 0.5 and c 5.0 respectively. The ratio of bound IgG to IgM was linearly related to the uptake pH. Both C4 AH and lysis were found to be optimum at pH 6.0--7.5, whereas the maximum C3 AH was at pH 6.0 +/- 0.5. The LISR performed at a constant pH (6.1 +/- 0.1) showed that an increasing concentration of neuraminidase (VCN) used in pretreatment of RBC was associated with a decrease in both IgG uptake and CF activity. A maximum VCN effect reduced the Ig uptake to c 20% of normal and abolished almost all the CF activity. An impaired LISR to various degrees was also observed with RBC pretreated with ficin, papain, bromelin, trypsin or protamine, and RBC from two individuals of En(a-) type. Preincubation of serum at LIS with and without RBC resulted in respectively a 'complete' and partial consumption of C in the fluid phase. The latter was not enhanced or inhibited by the addition of VCN-treated RBC for preincubation. A hypothesis is proposed suggesting that in the LSR the Ig uptake by RBC is an electrostatic interaction of the oppositely charged RBC and Ig and the CF to RBC results from C activation by the cell-bound IgG and IgM. In addition, a pH-dependent inactivation of the cell-bound C3 in the LISR is demonstrated.

A tissue-culture model of cartilage breakdown in rheumatoid arthritis. Quantitative aspects of proteoglycan release

1. The destruction of articular cartilage in human rheumatoid and other arthritides is the result of diverse mechanical, inflammatory and local cellular factors. A tissue-culture model for studying cartilage-synovial interactions that may be involved in the final common pathway of joint destruction is described. 2. Matrix breakdown was studied in vitro by using bovine nasal-cartilage discs cultivated in contact with synovium. Synovia were obtained from human and animal sources. Human tissue came from patients with ;classical' rheumatoid arthritis, and animal tissue from rabbits with antigen-induced arthritis. 3. Cartilage discs increased their proteoglycan content 2-3-fold during 8 days in culture. Proteoglycan was also released into culture medium, approx. 70% arising from cartilage breakdown. 4. Synovial explants from human rheumatoid and rabbit antigen-induced arthritis produced equivalent stimulation of proteoglycan release. After an initial lag phase, the breakdown rate rose abruptly to a maximum, resulting in a 2-fold increase of proteoglycan accumulation in culture medium after 8-10 days. 5. High-molecular-weight products shed into culture media were characterized chromatographically and by differential enzymic digestion. Proteoglycan-chondroitin sulphate accounted for 90% of the released polyanion, and its partial degradation in the presence of synovial explants was consistent with limited proteolytic cleavage. 6. Rheumatoid synovium applied to dead cartilage increased the basal rate of proteoglycan release. Living cartilage was capable of more extensive autolysis, even in the absence of synovium. However, optimal proteoglycan release required the interaction of living synovium with live cartilage. These findings support the view that a significant component of cartilage breakdown may be chondrocyte-mediated.

Ripley-like anti-Rh associated with red blood cell-bound IgG aggregates

A commercial Rho (D) immune globulin after heating at 63 C became Ripley-like in the Rh-positive red blood cells coated with this heated globulin carried biologic activities similar to those of red blood cells coated with Ripley anti-CD serum. These coated red blood cells fixed complement and were agglutinated by all 20 sera containing rheumatoid factor (RF). The RF-Rh-hemagglutinations were more readily inhibited by heated than by unheated human IgG. The heated globulin had no such effect on Rh-negative red blood cells. Fractionation studies by Na2SO4 precipitation and/or Sephadex G-200 gel filtration revealed that heat-induced IgG aggregates in heated globulin were responsible for the biological activities. In contrast, these activities in Ripley serum were carried by IgG monomers. Another anti-CD serum (Heyman), tested in paralledl, was found to be indistinguishable from Ripley. a pooled RF serum, after multiple adsorptions with red blood cells coated with globulin, lost its agglutination activity to red blood cells coated with Ripley or Heyman serum.

Role of sarcoplasmic reticulum phospholipids in calcium ion binding activity

The relationship between sarcoplasmic reticulum phospholipid and Ca(2+) binding by sarcoplasmic reticulum membranes was explored. Ca(2+) bound in the absence of ATP was defined as "ATP-independent Ca(2+) binding," and the additional amount of Ca(2+) bound in the presence of ATP was defined as "ATP-dependent Ca(2+) binding." The latter was found to be very sensitive to the loss of sarcoplasmic reticulum phospholipid; the amount of Ca(2+) bound was reduced when as little as 3% of the phospholipid was destroyed by phospholipase C. Further destruction of membrane phospholipid up to a 40% loss caused little or no further reduction of this Ca(2+) binding. However, when the destruction of phospholipid exceeded 40%, further loss of this Ca(2+) binding occurred, and there was an almost complete loss of this function when more than 60% of the sarcoplasmic reticulum phospholipid was destroyed.

The turnover of collagen in fibroblast cultures

Collagen turnover was studied in mouse fibroblast cultures (3T6) by radioactive labelling and compartmental analyses. The incorporation of [14C]proline into protein during continuous labelling rapidly reached a maximum value which was directly proportional to the medium specific activity. Radioactivity appeared more slowly in hydroxyproline, and gradually accumulated as cultures became enriched in collagen and its breakdown products. In relation to total new protein synthesis, the proportional synthesis of collagen, as measured by the formation of [14C]hydroxyproline, was less in logarithmically growing than in stationary-phase cultures, and little was deposited in the cell layer.

Newly synthesized hydroxyproline was consistently present in all growth media. In stationary-phase cultures, media contained as much as 60% of the total [14C]hydroxyproline in a form soluble in 0.5 M perchloric acid. Gel filtration chromatography confirmed that this was predominantly free hydroxyproline, only 30% appearing in small peptides whose degree of hydroxylation suggested their origin from larger collagen molecules. This acid-soluble compartment was taken as a convenient index of collagenolysis, which proved to be significant in both growth states, but was proportionately more important throughout logarithmic growth.

Reincubation of prelabelled cultures in fresh medium containing an excess of non-radioactive proline (‘chase’ medium) was followed by the degradative loss of labelled cell layer protein. The released radioactivity could be quantitatively recovered in the growth medium for periods up to 6 days; the rate of its appearance was little influenced by the frequency of feeding. Despite extensive dilution of the proline precursor-pool specific activity, synthesis of [14C]hydroxyproline continued in all chase cultures. The increment appeared largely as collagen breakdown products in the growth medium, and probably arose from 2 principal sources: (1) recently deposited collagen, and (2) the hydroxylation of peptidyl-[14C]proline residues in protocollagen. The balance between these contributions seemed to be dependent upon the extent to which ‘ageing’ of the cell layer collagen had occurred prior to initiating the chase. Radioactive hydroxyproline was rapidly lost from briefly prelabelled cell layers, but was well retained in a macromolecular form when the initial labelling period was sufficiently prolonged. It is proposed that the endogenous collagen-degradative apparatus attacks both young collagen and its polypeptide precursor, but that as the lability of the former substrate rapidly declines, enzyme activity continues to operate on protocollagen to yield [14C]hydroxyproline-containing breakdown products which gradually diminish as the latter substrate pool is exhausted.

Differential stimulation by parathyroid hormone of bone and kidney ribonucleic acid synthesis

The effects of parathyroid extract (PTE) on the synthesis in vivo of free nucleotide and RNA were compared in rat metaphysial bone and kidney. The incorporation of 32P into chromatographically pure acid-soluble 5′-AMP and purified bulk RNA was examined at various times after PTE administration. Pulse-labelled RNA was further characterized by sedimentation in sucrose density gradients and by ribomononucleotide analysis.

In both organs the labelling of 5′-AMP and its turnover were accelerated after administration of the hormone. The pool size of free AMP of kidney was approximately 3 times that of bone; neither was affected by PTE. The specific activity of pulse-labelled kidney AMP was always greater, and hormonal stimulation of its labelling was more rapid than in bone.

Despite more extensive precursor labelling, the stimulation of renal RNA synthesis was negligible, and was delayed for several hours, the overall hormonal effect being inseparable from its effect on phosphate entry into the nucleotide precursor pool.

In bone, the hormonal stimulation of RNA labelling was immediate, and continued to increase at a linear rate for up to 12 h. Initially, stimulation of RNA polymerization accounted for the total hormonal effect, while after 4 h an increasing proportion of the total increase in RNA labelling was attributable to enhanced precursor labelling.

Newly synthesized bone RNA differed qualitatively from kidney RNA in its sedimentation properties and composition. Although the labelling of all RNA species and RNA-nucleotides in bone was stimulated by PTE, there was a proportionately greater effect on the labelling of ribosomal RNA, and an apparent shift towards GMP-rich molecules, neither change being manifest in kidney.

It is concluded that while bone and kidney share certain mechanisms, they show changes in RNA biosynthesis in response to parathyroid hormone which are both quantitatively and qualitatively different and which are in accord with the RNA requirements for the respective physiological response of each.

Prejudice and conservatism in a recently integrated southern college

The study attempted to determine if token integration in a Southern school had seemed to improve racial feelings of white students toward Negroes. Indications are that students remain highly prejudiced. The authors concluded that passive non-involved contact between hostile groups does not reduce prejudice and hostility.

Validity of Seguin formboard with retarded children

Correlations for 172 retarded children (aged 6 to 15 yr.) of WISC standard scores and converted Seguin Formboard scores were small, only rs with Digit Span and Comprehension being significant. It was concluded that the Seguin is not valid with such children.

Synthesis of ribonucleic acid in normal bone in vitro

1. The incorporation of [2-(14)C]uridine into nucleic acids of bone cells was studied in rat and pig trabecular-bone fragments surviving in vitro. 2. The rapid uptake of uridine into trichloroacetic acid-soluble material, and its subsequent incorporation into a crude nucleic acid fraction of bone or purified RNA extracted from isolated bone cells, was proportional to uridine concentration in the incubation medium over a range 0.5-20.0mum. 3. During continued exposure to radioactive uridine, bulk RNA became labelled in a curvilinear fashion. Radioactivity rapidly entered nuclear RNA, which approached its maximum specific activity by 2hr. of incubation; cytoplasmic RNA, and particularly microsomal RNA, was more slowly labelled. The kinetics of labelling and rapid decline of the nuclear/microsomal specific activity ratio were consistent with a precursor-product relationship. 4. Bulk RNA preparations were resolved by zonal centrifugation in sucrose density gradients into components with approximate sedimentation coefficients 28s, 18s and 4s. 5. Rapidly labelled RNA, predominantly nuclear in location, demonstrated a polydisperse sedimentation pattern that did not conform to the major types of stable cellular RNA. Material of highest specific activity, sedimenting in the 4-18s region and insoluble in 10% (w/v) sodium chloride, rapidly achieved its maximum activity during continued exposure to radioactive precursor and decayed equally rapidly during ;chase' incubation, exhibiting an average half-life of 4.3hr. 6. Ribosomal 28s and 18s RNA were of lower specific activity, which increased linearly for at least 6hr. in the continued presence of radioactive uridine. There was persistent but variable incorporation into ribosomal RNA during ;chase' incubation despite rapid decline in total radioactivity of the acid-soluble pool containing RNA precursors.