A flow resistive inspiratory muscle training mask worn during high-intensity interval training does not improve 5 km running time-trial performance.

PURPOSE: There is little evidence of the ergogenic effect of flow-resistive masks worn during exercise. We compared a flow-resistive face mask (MASK) worn during high-intensity interval training (HIIT) against pressure threshold loading inspiratory muscle training (IMT). METHODS: 23 participants (13 males) completed a 5 km time trial and six weeks of HIIT (3 sessions weekly). HIIT (n = 8) consisted of repeated work (2 min) at the speed equivalent to 95% [Formula: see text]O2 peak with equal rest. Repetitions were incremental (six in weeks 1, 2 and 6, eight in weeks 3 and 4 and ten in week 5). Participants were allocated to one of three training groups. MASK (n = 8) wore a flow-resistive mask during all sessions. The IMT group (n = 8) completed 2 × 30 breaths daily at 50% maximum inspiratory pressure (PImax). A control group (CON, n = 7) completed HIIT only. Following HIIT, participants completed two 5 km time trials, the first matched identically to pre-intervention trial (ISO time), and a self-paced effort. RESULTS: Time trial performance was improved in all groups (MASK 3.1 ± 1.7%, IMT, 5.7 ± 1.5% and CON 2.6 ± 1.0%, p < 0.05). IMT improved greater than MASK and CON (p = 0.004). Post intervention, PImax and diaphragm thickness were improved in IMT only (32% and 9.5%, respectively, p = 0.003 and 0.024). CONCLUSION: A flow-resistive mask worn during HIIT provides no benefit to 5 km performance when compared to HIIT only. Supplementing HIIT with IMT improves respiratory muscle strength, morphology and performance greater than HIIT alone.

An anatomical evaluation of the serratus anterior plane block.

The serratus anterior plane block has been described for analgesia of the hemithorax. This study was conducted to determine the spread of injectate and investigate the anatomical basis of the block. Ultrasound-guided serratus anterior plane block was performed on six soft-fix embalmed cadavers. All cadavers received bilateral injections, on one side performed with 20 ml latex and on the other with 20 ml methylene blue. Subsequent dissection explored the extent of spread and nerve involvement. Photographs were taken throughout dissection. The intercostal nerves were involved on three occasions with dye, but not with latex. The lateral cutaneous branches of the intercostal nerve contained dye and latex on all occasions. The serratus plane block appears to be mediated through blockade of the lateral cutaneous branches of the intercostal nerves. Anatomically, serratus plane block does not appear to be equivalent to paravertebral block for rib fracture analgesia.

The captive husbandry and reproduction of the pink-eared turtle (Emydura victoriae) at Perth Zoo.

In 1997, Perth Zoo acquired six pink-eared turtles (Emydura victoriae) from the wild for display in the reptile facility. There is very little documented information on pink-eared turtles in captivity. This article looks at the reproductive biology, ecology, behavior, diet, and captive husbandry of the species. Eight clutches of eggs were documented over a 2-year period with an average clutch size of 10 eggs. Egg size was recorded with three clutches incubated to hatching. Ten hatchlings were maintained for a growth and development study. Measurements of weight, carapace length, width, height, and plastron length were recorded weekly for about 12 months, and then monthly for approximately 2 years. The data were analyzed and showed positive growth curves in all animals. Sexual dimorphism was observed after 20 weeks and sexual maturity in males observed after 2 years.

Search for Randall-Sundrum gravitons in the dielectron and diphoton final states with 5.4 fb(-1) of data from pp collisions at square root(s) = 1.96 TeV.

Using 5.4 fb(-1) of integrated luminosity from pp collisions at square root(s)=1.96 TeV collected by the D0 detector at the Fermilab Tevatron Collider, we search for decays of the lightest Kaluza-Klein mode of the graviton in the Randall-Sundrum model to ee and γγ. We set 95% C.L. lower limits on the mass of the lightest graviton between 560 and 1050 GeV for values of the coupling k/M(Pl) between 0.01 and 0.1.

Composition, coagulation properties, and cheesemaking potential of milk from cows undergoing extended lactations in a pasture-based dairying system.

Extending the lactation length of dairy cows beyond the traditional 10 mo toward lactations of up to 22 mo has attracted interest in the pasture-based seasonal dairying systems of Australia and New Zealand as a way of alleviating the need for cows to conceive during peak lactation, such as is required to maintain seasonally concentrated calving systems. Lactation lengths longer than 10 mo instead provide cows with more time to cycle and conceive after parturition and may therefore be more suitable systems for high-producing Holstein-Friesian cows. Before recommending such systems there is a need to evaluate the effects of long lactations on the suitability of milk for manufacture of high-quality dairy products. In the current experiment, the composition of milk from cows entering the second half of a 22-mo lactation was examined in detail and compared with that from cows undergoing a traditional 10-mo lactation. On 2 occasions, coagulation properties were measured using low amplitude strain oscillation rheometry, and Cheddar cheese was made in 250-L pilot-scale vats. Results showed that milk from extended lactations had higher concentrations of fat and protein than cows undergoing 10-mo lactations under similar management conditions and at the same time of year. The ratio of casein to true protein was not affected by lactation length and neither were the proportions of individual caseins. The increase in milk solids during extended lactations translated into a more rapid rate of coagulation and ultimately a firmer curd on one of the two occasions. Milk from extended lactations yielded more cheese per 100 kg of milk, and there were few differences in the composition or organoleptic properties of the cheese. These data are the first to show that pasture-based dairy industries could embrace the use of extended lactations without compromising the core business of producing high-quality dairy products.

Can a brief behavioural change intervention encourage hospital patients with low physical activity levels to engage and initiate a change in physical activity behaviour?

BACKGROUND: Regular physical activity (PA) reduces risk factors for chronic disease. This novel study evaluates self-reported engagement with PA in recently discharged patients, identified as having low PA levels, who agreed to participate in an in-patient behaviour change intervention. METHOD: This exploratory study invited hospital in-patients, who were classified as 'moderately inactive' or 'inactive', to participate in a brief individual physiotherapy-led motivational interviewing (MI) behavioural change intervention. Patients were encouraged to set individual exercise and activity goals, and an appropriate programme referral was identified and agreed upon. RESULTS: Three hundred and forty-two of 526 patients, who were screened between January 2017 and March 2018, were classified 'inactive' or 'moderately inactive'. Seventy-seven percent of patients consented to participate in the brief MI intervention (n=58 'moderately active', n=206 'inactive'). One hundred percent participants who received the brief intervention agreed to attend a PA programme. At telephone follow-up, 66% self-reported engagement in community exercise or independent PA initiatives. CONCLUSION: This exploratory study demonstrates that a brief, MI-facilitated, behaviour change intervention is feasible and has the potential to aid PA engagement for hospital patients with low PA levels upon discharge from hospital. Considering that the 'first-step' with engagement in PA is often the biggest challenge for patients, this initiative has promise to improve PA behaviour and could be rolled out across the National Health Service (NHS).

Development and application of an enzyme-linked immunosorbent assay for the quantitation of alternative complement pathway activation in human serum.

We have developed a new, specific, and highly sensitive enzyme-linked immunosorbent assay (ELISA) which quantitates activation of the alternative pathway in human serum, plasma, or on the surface of activators. The ELISA detects the third component of complement (C3b), proteolytic fragment of complement Factor B (Bb), and properdin (P) complex or its derivative product, C3b,P. In the method, activator-plasma mixtures, plasma containing an activated alternative pathway, or other samples are added to the wells of microtitration plates precoated with antibody to P. C3b, Bb,P or C3b,P complexes which become bound are quantitated by subsequently added, enzyme-labeled, anti-C3. The resulting hydrolysis of the chromogenic substrate is expressed as nanograms of C3b by reference to a C3 standard curve. In addition to absolute specificity for activation of the pathway because of the nature of the complex detected by the assay, the ELISA is highly sensitive and able to reproducibly detect 10-20 ng/ml of C3b,P complexes in serum. This value corresponds to 0.0015% of the C3 in serum. In a series of studies to validate the parameters of the ELISA, reactivity was found to be dependent on the presence of alternative pathway proteins, the functional integrity of the pathway, and on the presence of magnesium. Sheep erythrocytes were converted to activators by treatment with neuraminidase. By using a variety of activators, the kinetics of activation and the numbers of bound C3b molecules quantitated by the ELISA were very similar to those measured by C3b deposition. The ELISA also detected identical activation kinetics when MgEGTA-serum and a mixture of the purified alternative pathway proteins were used as sources of the pathway. ELISA reaction kinetics also correlated with the restriction index, a measure of alternative pathway-activating ability. These studies cumulatively validate the ELISA as a direct and quantitative assay for alternative pathway activation. The sensitivity of the ELISA has permitted its use to detect direct alternative pathway activation by several viruses. The ELISA has also shown that certain classical pathway activators trigger the amplification loop of the alternative pathway while others do not. In addition, stable ELISA reactive complexes appeared in the supernatant of mixtures of serum with certain, but not other activators. The ability of the ELISA to detect activation which has already occurred and the stability of the reactive complexes permits studies of clinical sera. Normal human sera (20) contained low levels (5-20 ng/ml) of ELISA-reactive complexes. A proportion of sera from individuals with the adult respiratory distress syndrome (9-10), typhoid fever (8-10), malaria (3-5), gram-negative sepsis (9 of 47), acute trauma and shock (6 f 25), and systemic lupus erythematosus (3 of 29) showed elevated levels of complexes reactive in the alternative pathway ELISA. In contrast, nine sera from patients with circulating C3 nephritic factor were not reactive in the ELISA.

Short Term Clinical Outcome after Laparoscopic Cryoablation of the Renal Tumor < or = 3.5 cm.

Between September 2000 and September 2006, 26 patients underwent primary laparoscopic cryosurgical procedures (28) for an organ-confined renal tumor(s). In one case, cryosurgery was done sequentially on both kidneys. All patients had been carefully selected based on the following criteria: tumor size < or = 3.5 cm, the absence of local and systemic spread on cross-sectional computed tomography (CT) or magnetic resonance imaging (MRI), and the ability to tolerate general anesthesia. A pure laparoscopic approach was employed using third generation cryotechnology (Galil Medical Inc., Plymouth Meeting, USA). Patients were followed by serial CT or MRI scan, creatinine level, and physical examination at least every six months after cryotherapy. The mean patient age was 64 years (range: 44-79) and the mean follow-up was 20.9 +/- 17.2 months. The median tumor size was 2.0 cm (range: 1-3.5 cm). Only one patient required a blood transfusion and one patient developed a transient ileus. The median length of stay was 2.0 days (range: 0-9 days). The median change in creatinine was 0.1 mg/dl (range:-0.4 to 1.8). No patient was converted to open surgery. No evidence of recurrence or progression was found in all patients, and overall survival rate was 100%. Laparoscopic renal cryoablation of the small renal tumor is a safe procedure with minimal complications. Although there were no recurrences with short term follow-up, further long term study is needed to verify its efficacy.

HT1080/DR4: a P-glycoprotein-negative human fibrosarcoma cell line exhibiting resistance to topoisomerase II-reactive drugs despite the presence of a drug-sensitive topoisomerase II.

HT1080/DR4 (DR4) is a doxorubicin-resistant human fibrosarcoma line that exhibits 150-fold cross-resistance to etoposide but does not overexpress P-glycoprotein (one mechanism of multiple drug resistance). We examined another possible mechanism that could explain resistance to both doxorubicin and etoposide: a quantitative or qualitative alteration in topoisomerase II, the putative nuclear target of these agents. The amount of immunoreactive topoisomerase II present in whole-cell lysates and nuclear extracts was three- to 10-fold lower in DR4 than in HT1080 cells. However, the topoisomerase II in nuclear extracts from both lines was sensitive to the effects of amsacrine (AMSA) and etoposide. Following treatment with AMSA, etoposide, and 5-iminodaunorubicin, topoisomerase II-mediated DNA cleavage in DR4 cells and nuclei was reduced compared with cleavage in HT1080 parent cells and nuclei. The difference between the HT1080 and DR4 lines in AMSA- and 5-iminodaunorubicin-induced cleavage was similar in cells and nuclei and could be due to the lower amount of DR4 topoisomerase II. By contrast, the difference between the HT1080 and DR4 lines in etoposide-induced DNA cleavage was much greater in cells than in nuclei. This finding suggested that cytosolic factors, removed from isolated nuclei, could influence the susceptibility of intact cells to the cytotoxic and DNA-cleaving actions of etoposide. The specific activities of several antioxidant enzymes, components of the cell's defense against free-radical damage that may be produced by doxorubicin or etoposide, were significantly different in HT1080 and DR4 cytosolic extracts. These differences may constitute an additional mechanism of resistance. Regardless, the magnitude of the resistance of DR4 to doxorubicin and etoposide cannot be explained solely on the basis of a topoisomerase II-related mechanism.

Phorbol ester effects on topoisomerase II activity and gene expression in HL-60 human leukemia cells with different proclivities toward monocytoid differentiation.

We examined the effects of phorbol ester treatment on topoisomerase II-mediated events in two human leukemia cell lines with different proclivities toward phorbol ester-induced monocytoid differentiation. HL-60 is the parent line that will terminally differentiate; 1E3 is a derived line that will not terminally differentiate. Within 24 h of phorbol ester treatment, etoposide-induced, topoisomerase II-mediated DNA cleavage declined 10-fold, whereas 4'-(9-acridinylamino)-methanesulfon-m-anisidide- induced DNA cleavage declined 3-fold in HL-60. In phorbol-treated 1E3, etoposide-induced DNA cleavage declined only 2-fold, whereas 4'-(9-acridinylamino)methanesulfon-m-anisidide-induced cleavage was barely affected. There was a 2- to 3-fold decline in topoisomerase II activity within the nuclear extracts from phorbol-treated HL-60 cells but not from phorbol-treated 1E3 cells. Immunoblotting experiments with anti-topoisomerase II antibodies indicated that phorbol treatment produced a structural change in the immunoreactive topiosomerase II in HL-60 nuclear extracts but produced no change in 1E3 topoisomerase II. Phorbol ester treatment also produced a decline in the level of topoisomerase II gene expression in HL-60 but not in 1E3 cells. By contrast, the cytotoxicity of etoposide in both lines was decreased following phorbol treatment. Thus, phorbols may uncouple the mechanisms linking drug-induced, topoisomerase II-DNA cleavable complex stabilization with drug-induced cytotoxicity, particularly in 1E3.

Effect of phorbol ester treatment on drug-induced, topoisomerase II-mediated DNA cleavage in human leukemia cells.

Tumor-promoting phorbol esters such as phorbol 12-myristate 13-acetate (PMA) induce the monocytoid differentiation of HL-60 human leukemia cells. The cellular receptor for PMA is protein kinase C. However, cellular events distal to protein kinase C phosphorylation are also critical steps toward differentiation. These events may include specific programs of oncogene transcription that have been associated with phorbol ester-induced leukemic cell differentiation. Recently, it has been found that topoisomerase II could be activated by protein kinase C-mediated serine phosphorylation and that PMA treatment of HL-60 cells enhanced extractable topoisomerase II from these cells. Additionally, topoisomerase II-reactive antineoplastic drugs could block PMA-induced differentiation of HL-60. This enzyme has been implicated in gene regulation, and drug-induced, topoisomerase II-mediated DNA cleavage sites have been identified within cellular oncogenes. Thus, topoisomerase II could play a critical role in the signal transduction cascade leading from PMA-protein kinase interaction to monocytoid differentiation. We have examined this relationship between topoisomerase II and PMA-induced differentiation through measurements of drug-induced, topoisomerase II-mediated DNA cleavage (via alkaline elution) in PMA-treated HL-60 cells. Etoposide-induced DNA cleavage was reduced 10-fold in HL-60 cells treated with 10 nM PMA for 24 h. Neither dimethyl sulfoxide (which produces granulocytoid differentiation) nor non-differentiation-inducing phorbol esters could produce this effect. The decreased cleavage was not due to a PMA-induced inhibition of cell-associated etoposide and was demonstrable in nuclei isolated from PMA-treated cells. The decrease was not simply related to decreased cellular proliferation rate as reflected in the inhibition of DNA synthesis because conditions leading to marked inhibition of DNA synthesis did not necessarily inhibit etoposide-induced DNA cleavage. By contrast, lower concentrations of PMA inhibited etoposide-mediated DNA cleavage disproportionately compared with PMA effects on DNA synthesis. Interestingly, PMA reduced cleavage induced by the topoisomerase II-reactive DNA intercalator 4'-(9-acridinylamino)methanesulfon-m-anisidide by 2-fold, suggesting that specific drug-DNA interactions could partially overcome the PMA-induced effect that resulted in decreased etoposide-induced, topoisomerase II-mediated DNA cleavage. Nuclear proteins in 0.35 M NaCl extracts from untreated or PMA-treated HL-60 cells were virtually identical in topoisomerase II activity and in topoisomerase II-associated drug sensitivity.(ABSTRACT TRUNCATED AT 400 WORDS)

Identification of a point mutation in the topoisomerase II gene from a human leukemia cell line containing an amsacrine-resistant form of topoisomerase II.

HL-60/AMSA is a human leukemia cell line that is 50- to 100-fold more resistant to the cytotoxic actions of the topoisomerase II-reactive intercalator amsacrine than is its drug-sensitive HL-60 parent line. Previously, we have shown that the topoisomerase II from HL-60/AMSA is also resistant to inhibition by amsacrine and other intercalating agents. We therefore sought the molecular basis for the resistance of the topoisomerase II of HL-60/AMSA and, by inference, of the HL-60/AMSA line itself. We report the cloning and sequencing of the topoisomerase II genes from both the sensitive and resistant leukemia cell lines using polymerase chain reaction technology. We have identified a single base change associated with the drug-resistant form of topoisomerase II. This mutation is present in both cloned HL-60/AMSA complementary DNA and extracted HL-60/AMSA genomic DNA. A rapid assay for this mutation in clinical samples has been developed and applied to the DNA of cells from both normal volunteers and leukemia patients. Thus far, the HL-60/AMSA genotype has not been identified in the cells from any individual, suggesting that this genotype is indeed a mutation and not an allelic form of topoisomerase II. The novel assay developed will allow a rapid search for the prevalence of this mutation in clinical samples from patients with leukemia who have relapsed following intercalator therapy.

Relative activity of structural analogues of amsacrine against human leukemia cell lines containing amsacrine-sensitive or -resistant forms of topoisomerase II: use of computer simulations in new drug development.

Anilino analogues of amsacrine showed increased activity against amsacrine (AMSA)-resistant cell lines when compared with the parent compound, but the mechanisms of amsacrine resistance in these lines were unknown (Finlay, G. J., Baguley, B. C., Snow, K., and Judd, W., J. Natl. Cancer Inst., 82: 662-667, 1990). We tested the cytotoxic and DNA-cleaving activities of two amsacrine analogues which were derivatives of 9-anilinoacridine (1'-methylcarbamate and 1'-benzenesulfonamide) against an amsacrine-resistant human leukemia cell line (HL-60/AMSA) whose resistance is due to an amsacrine-resistant topoisomerase II. Neither agent could overcome the amsacrine resistance of HL-60/AMSA. Neither agent could induce HL-60/AMSA topoisomerase II-mediated cleavage of DNA in an isolated biochemical system, although at high concentrations the two analogues could inhibit HL-60/AMSA topoisomerase II-mediated DNA strand passage. Both analogues were at least as active, if not more active, than amsacrine against amsacrine-sensitive HL-60 and its topoisomerase II. Comparison of the cellular and biochemical results with those from computer simulation of the energy-minimized structures of amsacrine, its inactive isomer o-AMSA, and the two new active analogues suggests the following possibilities: (a) the positioning of the potential topoisomerase II-binding site (1'-anilino group) of the two new drugs resembles the positioning of this site in amsacrine; (b) the HL-60 topoisomerase II has a binding site which interacts with amsacrine and the two anilino analogues but not with o-AMSA, an analogue with altered positioning of the methoxy group; (c) the HL-60/AMSA topoisomerase II interacts with reduced affinity with amsacrine and the two anilino analogues, although HL-60/AMSA topoisomerase II still interacts with the structurally distinct topoisomerase II-reactive nonintercalator, etoposide; (d) because of their higher DNA binding affinity or the greater possible positions of their side groups in comparison to amsacrine, the two analogues can, at high concentrations, inhibit the strand-passing activity of HL-60/AMSA topoisomerase II.

alpha-galactosidase A from human placenta. Stability and subunit size.

alpha-Galactosidase A (alpha-D-galactoside galactohydrolase, EC 3.2.1.22) was purified from human placenta. The purified enzyme showed one major band on polyacrylamide gel electrophoresis and a single precipitin line on double immunodiffusion. Electrophoresis of the purified, S-carboxymethylated enzyme on sodium dodecyl sulfate polyacrylamide gel showed one component with a molecular weight of about 65 000, but electrophoresis of the non-S-carboxymethylated enzyme showed two components, a major band with a molecular weight of 67 500 and a diffuse band with a molecular weight of 47 000. We suggest that the smaller diffuse component is a degradation product and that the enzyme is a dimer with a molecular weight of approximately 150 000 and a subunit of molecular weight of about 67 500. Antibody raised against the purified enzyme quantitatively precipitated alpha-galactosidase A, but not alpha-galactosidase in Fabry's disease fibroblasts. The alpha-galactosidase A is very heat labile and pH sensitive. It is most stable in concentrated solution at low temperature and at a pH of 5.0 to 6.0. When added to plasma at 37 degrees C, it has a half-life of only 17 min. This imposes a serious obstacle to its use in the treatment of Fabry's disease.

Complement activation by the surface of Plasmodium falciparum infected erythrocytes.

The surface of trophozoite-stage Plasmodium falciparum infected erythrocytes will, in the presence of immune human or owl monkey serum, activate the classical complement pathway. This was demonstrated with a sensitive, enzyme-linked immunosorbent assay which detects the complex, C1s-C1 inhibitor, which is only generated when the classical pathway is activated. A second enzyme-linked immunosorbent assay, as well as Covaspheres coated with affinity-purified anti-C3, showed that immune activation of the classical pathway by infected erythrocytes resulted in the accumulation of significant amounts of C3b on the erythrocyte surface. During the development of the parasite to the trophozoite stage, the erythrocyte membrane is also transformed from a non-activator into a surface capable of activating complement by the alternative pathway. Erythrocytes infected with trophozoite-stage parasites directly activated the alternative complement pathway. This activation led to the specific binding of an average of 15,000 C3b molecules per infected cell. Alternative pathway activation was augmented by anti-parasite antibody. Such conditions mediated the accumulation of an average of 36,000 C3b molecules per infected erythrocyte. The amounts of C3b on the infected erythrocyte surface did not lead to cellular lysis. They are, however, likely to have a major impact on the total in vivo response to this parasite.

Direct effects of sex steroid hormones on adipose tissues and obesity.

Sex steroid hormones are involved in the metabolism, accumulation and distribution of adipose tissues. It is now known that oestrogen receptor, progesterone receptor and androgen receptor exist in adipose tissues, so their actions could be direct. Sex steroid hormones carry out their function in adipose tissues by both genomic and nongenomic mechanisms. In the genomic mechanism, the sex steroid hormone binds to its receptor and the steroid-receptor complex regulates the transcription of given genes. Leptin and lipoprotein lipase are two key proteins in adipose tissues that are regulated by transcriptional control with sex steroid hormones. In the nongenomic mechanism, the sex steroid hormone binds to its receptor in the plasma membrane, and second messengers are formed. This involves both the cAMP cascade and the phosphoinositide cascade. Activation of the cAMP cascade by sex steroid hormones would activate hormone-sensitive lipase leading to lipolysis in adipose tissues. In the phosphoinositide cascade, diacylglycerol and inositol 1,4,5-trisphosphate are formed as second messengers ultimately causing the activation of protein kinase C. Their activation appears to be involved in the control of preadipocyte proliferation and differentiation. In the presence of sex steroid hormones, a normal distribution of body fat exists, but with a decrease in sex steroid hormones, as occurs with ageing or gonadectomy, there is a tendency to increase central obesity, a major risk for cardiovascular disease, type 2 diabetes and certain cancers. Because sex steroid hormones regulate the amount and distribution of adipose tissues, they or adipose tissue-specific selective receptor modulators might be used to ameliorate obesity. In fact, hormone replacement therapy in postmenopausal women and testosterone replacement therapy in older men appear to reduce the degree of central obesity. However, these therapies have numerous side effects limiting their use, and selective receptor modulators of sex steroid hormones are needed that are more specific for adipose tissues with fewer side effects.

Intrauterine injection of ovine interferon-tau alters oestrogen receptor and oxytocin receptor expression in the endometrium of cyclic ewes.

This study determined the effects of intrauterine injections of recombinant ovine interferon-tau; (roIFN-tau; 2 x 10(7) antiviral units/day) or control proteins (6 mg/day) from day 11 to day 14 post-oestrus = day 0) on endometrial expression of receptors fro oestrogen, progesterone and oxytocin in cyclic ewes. Plasma concentrations of progesterone were greater on day 15 in ewes receiving roIFN-tau compared with control proteins (P < 0.02, treatment x day). Ewes injected with roIFN-tau had lower endometrial levels or oestrogen receptor mRNA (P > 0.10) and protein (P < 0.01) on day 15 compared with ewes receiving control proteins. In situ hybridization analysis indicated that oestrogen receptor mRNA was more abundant in the luminal and glandular epithelium of control ewes compared with roIFN-tau-treated ewes. Immunoreactive oestrogen receptor was also present in the luminal and glandular epithelium of control, but not roIFN-tau-treated ewes. Endometrial levels of progesterone receptor mRNA and protein were not different (P > 0.10) between control and roIFN-tau-treated ewes. In situ hybridization analyses indicated that progesterone receptor mRNA abundance was low in endometrial epithelium and stroma of both control and roIFN-tau-injected ewes. Immunoreactive progesterone receptors were present in the endometrial stroma and epithelium of control ewes, but confined to the stroma of roIFN-tau-treated ewes. Oxytocin receptor density was lower (P < 0.01) in the endometrium of ewes injected with roIFN-tau than control proteins; however, oxytocin receptor affinity was not affected (P > 0.10) by treatment. Concentrations of 13,14-dihydro-15-ketoprostaglandin F2a (PGFM) were not increased by exogenous oxytocin administration in control and roIFN-tau-treated ewes on days 10 or 12 post-oestrus. However, on day 14, control ewes responded to oxytocin with increased plasma concentrations of PGFM, whereas ewes receiving roIFN-tau remained unresponsive to oxytocin. These results indicate that the an tiluteolytic effects of IFN-tau are to prevent increases in endometrial oestrogen receptor MRNA and protein and oxytocin receptor density which abrogates uterine release of prostaglandin F2a during maternal recognition of pregnancy. IFN-tau may inhibit the synthesis of oestrogen receptor mRNA by a transcriptional or post-transcriptional regulatory mechanism to suppress oxytocin receptor formation during early pregnancy in ewes.

Inhibition of anti-OKT3 antibody generation by cyclosporine--results of a prospective randomized trial.

To investigate the influence of therapy with cyclosporine on the generation of antibodies to OKT3, 51 renal transplant recipients previously maintained on CsA, azathioprine, and prednisone were allocated randomly either to receive 50% of their maintenance dose of CsA (group 1, n = 27) or to discontinue CsA (group 2, n = 24) during treatment with OKT3 for acute renal allograft rejection. In the month following therapy with OKT3, anti-OKT3 antibodies were detected in 11% of patients in group 1 and in 42% of patients in group 2 (P less than 0.02). No patient in group 1 developed antibody titers greater than 1:100, whereas 4 patients in group 2 developed titer greater than or equal to 1:1000. Rejection was reversed in 96% of patients in group 1 and in only 75% of patients in group 2 (P less than 0.03), suggesting that continued administration of reduced doses of CsA during therapy with OKT3 improves the short-term response to this monoclonal antibody. Results of this study suggest that concurrent administration of CsA during therapy with OKT3 inhibits the generation of anti-OKT3 antibodies and improves the response to this monoclonal antibody.

Reexposure to OKT3 in renal allograft recipients.

Between 40% and 80% of patients treated with the monoclonal antibody OKT3 develop blocking antibody against its idiotypic region. Thus a major concern with the use of OKT3 as part of a baseline immunosuppressive regimen is that formation of blocking antibodies might preclude its subsequent use. Between 7/86 and 2/87, 32 patients received prophylactic OKT3 in addition to low-dose prednisone, azathioprine, and cyclosporine. Prophylactic OKT3 did not prevent rejection, as 21 of 32 patients studied developed rejection. Retreatment of 13 patients with OKT3 successfully reversed 12 rejections and lowered the number of T3-positive cells in spite of a low level of blocking antibody in two patients in this group. Of the patients analyzed, 38% developed blocking antibody on initial exposure to OKT3, but OKT3 reuse was denied only 4 patients due to the presence of these antibodies. Three of these had rejections reversed with steroids alone; the other patient lost the allograft. A high frequency of infectious complications occurred in the retreatment group, with viral infections predominating. Only one patient in the retreated group developed antibodies after the second use. Appearance of blocking antibodies after use of OKT3 as part of a base-line prophylactic immunosuppressive regimen did not significantly compromise access to OKT3 for treatment of subsequent rejection episodes, but multiple exposures to OKT3 did increase the frequency of infectious complications.

The effects of steroid withdrawal on the lipoprotein profiles of cyclosporine-treated kidney and kidney-pancreas transplant recipients.

Lipoprotein profiles were measured before and two months after complete withdrawal of prednisone in 34 kidney and 9 kidney-pancreas transplant recipients subsequently maintained on cyclosporine and azathioprine. Withdrawal of steroid therapy was accompanied by a 17% reduction in total serum cholesterol levels. However, there was a parallel reduction in all other measured lipoprotein concentrations, including an 18% reduction in high-density lipoprotein cholesterol levels. In diabetic recipients of a kidney or kidney-pancreas transplant, the ratio of total to high-density lipoprotein cholesterol was unchanged after steroid withdrawal. In nondiabetic kidney transplant recipients, this ratio actually increased significantly following withdrawal of prednisone. These observations suggest that it is premature to presume that withdrawal of steroid therapy will reduce the cardiovascular risk related to hyperlipidemia in cyclosporine-treated kidney or kidney-pancreas transplant recipients.