ICARUS at the Fermilab Short-Baseline Neutrino program: initial operation

The ICARUS collaboration employed the 760-ton T600 detector in a successful 3-year physics run at the underground LNGS laboratory, performing a sensitive search for LSND-like anomalous ν e appearance in the CERN Neutrino to Gran Sasso beam, which contributed to the constraints on the allowed neutrino oscillation parameters to a narrow region around 1 eV2 . After a significant overhaul at CERN, the T600 detector has been installed at Fermilab. In 2020 the cryogenic commissioning began with detector cool down, liquid argon filling and recirculation. ICARUS then started its operations collecting the first neutrino events from the booster neutrino beam (BNB) and the Neutrinos at the Main Injector (NuMI) beam off-axis, which were used to test the ICARUS event selection, reconstruction and analysis algorithms. ICARUS successfully completed its commissioning phase in June 2022. The first goal of the ICARUS data taking will be a study to either confirm or refute the claim by Neutrino-4 short-baseline reactor experiment. ICARUS will also perform measurement of neutrino cross sections with the NuMI beam and several Beyond Standard Model searches. After the first year of operations, ICARUS will search for evidence of sterile neutrinos jointly with the Short-Baseline Near Detector, within the Short-Baseline Neutrino program. In this paper, the main activities carried out during the overhauling and installation phases are highlighted. Preliminary technical results from the ICARUS commissioning data with the BNB and NuMI beams are presented both in terms of performance of all ICARUS subsystems and of capability to select and reconstruct neutrino events.

Abstract P6-17-26: Care 001: multi-center randomized open-label phase II trial of neoadjuvant trastuzumab emtansine (T-DM1) in combination with lapatinib and nab-paclitaxel compared with paclitaxel, trastuzumab and pertuzumab in HER2-neu over-expressed breast cancer patients (TEAL study)

Background: We conducted a multicenter, randomized open-label phase II neoadjuvant study of trastuzumab-emtansine (T-DM1), Lapatinib (L) and Nab Paclitaxel (Nab-P) compared to standard of care (SOC) Paclitaxel (Pac), Trastuzumab (T), and Pertuzumab (P) in patients with HER2 over-expressed breast cancer.

Methods: Patients in the experimental arm received a biologic window of targeted therapies alone for 6 weeks (T-DM1 and L) followed by T-DM1 3.0 mg/kg Q3W, L 750mg oral daily and Nab-P 80 mg/m2 weekly (QW) X 12 weeks. Patients in SOC arm received targeted therapies alone for 6 weeks (T and P) followed by Pac 80mg/m2QW, T 2mg/kg QW, and P 420mg Q3W X 12 weeks. The primary objective was to evaluate the proportion of patients with residual cancer burden (RCB) 0 or 1. Key secondary objectives included correlative assessments of PIK3CA mutations, PTEN expression, and HER2 subtypes which are being reported.

Results: Thirty of the 33 enrolled patients were evaluable. Patient demographics were well balanced. HER2 subtypes and altered PIK3CA (low PTEN or PIK3CA mutations) pathway were not statistically different between both arms. We have previously reported that all patients achieved RCB 0 & I in the T-DM1, L and Nab-P arm, compared to SOC (100% vs. 62.5%, p 0.0035). In the SOC arm, the 6 week change in tumor size on breast MRI during targeted biologic window treatment is significantly different between the responders and non-responders based on two-sided Wilcoxon rank-sum test (p =0.0065). Consistent with literature, among ER positive patients treated with SOC, PTEN low expressers were less likely to respond (0%, 0 of 2) than PTEN high expressers (67%, 2 of 3). In the experimental arm, all patients responded regardless of PTEN. There was only 1 PIK3CA mutation on the experimental arm where all responded.

Table 1:Breast MRI Tumor Size Standard of Care ArmResponseNMeanStandard Deviation95% CL MeanMinimumMaximumNo6-0.13330.4457-0.60110.3344-1.00.3Yes52.58001.88330.24154.91850.24.9Sixteen patients total were present in standard of care arm but 5 had incomplete imaging data.

Conclusions: TDM1 plus L and Nab-P therapy was well tolerated with noteworthy responses in all patients, including in PTEN low expressers. Change in tumor size at 6 weeks of biologic therapies was significant between responders and non-responders and can be evaluated as a surrogate for future studies.

Citation Format: Creamer SL, Patel TA, Ensor JE, Rodriguez AA, Niravath PA, Darcourt JG, Kaklamani VG, Meisel JL, Li X, Zhao J, Kuhn JG, Rosato RR, Qian W, Belcheva A, Boone T, Chang J. Care 001: multi-center randomized open-label phase II trial of neoadjuvant trastuzumab emtansine (T-DM1) in combination with lapatinib and nab-paclitaxel compared with paclitaxel, trastuzumab and pertuzumab in HER2-neu over-expressed breast cancer patients (TEAL study) [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P6-17-26.

[Role of the community pharmacist in the management of drug related problems in home care patients]

Medication management in home care is an error prone process. In a small pilot project in Flanders, community pharmacists collaborated with physicians and home care nurses through a shared electronic care plan, to optimize the medication management of their home care patients. The pilot project shows that GPs and nurses are positive about the possible contribution of the pharmacist in medication management of home care patients. A larger follow up study is necessary to further identify possible roles of pharmacists in home care and to show related health benefits.

A Technique for Preparing Transmission Electron Microscope Specimens Using Cleavage

A technique for observing both plan view and cross sections of a specimen directly in a transmission electron microscope (TEM) without relying on a tedious thinning operation was developed. This technique involves cleaving a specimen perpendicular to the plane, so that the thin (electron transparent) section of the cleaved edge can be directly imaged by TEM. The only limitations of this technique are that a specimen must be readily criacked or cleaved and that, since the transparent region is often bounded by a 90° corner, the extent of electron transparent region is somewhat localized. Nevertheless, the technique has the advantages of the ease of specimen preparation, and the absence of contamination or damage introduced in other conventional thinning methods. The geometry of the cleaved specimen is also suitable for reflection electron microscopy.

Minimization of Interfacial Microroughness for 13–60 Å Ultrathin Gate Oxides

By using a combination of smooth epi substrates (0.7 Å rms roughness), in-situ UV/Cl2 processing, and rapid thermal oxidation, highly reliable ultrathin gate oxides were produced with ≤ 1.0 Å rms interface roughness.

Effect of blood donation on maximal oxygen consumption

AIM

This study determined the effect of donating one unit of blood on various physiological parameters associated with a VO2(max) test.

METHODS

Ten healthy, male subjects (23+/-4 years, 178+/-7.6 cm, 74.4+/-12.3 kg) completed a VO2(max) test 24 h before donating one unit of blood (~500 mL) and 24 h after donating blood. The Bruce protocol was used to determine the subjects' VO2(max). Physiological responses were measured at the end of the VO2(max) test. A repeated measures ANOVA was used to determine if there were significant (P<0.05) differences in the subjects' physiological responses between the VO2(max) before and after blood donation.

RESULTS

Significant differences were found in VO2(max) (mean+/-SD, 3.18+/-0.74 vs 2.87+/-0.53 L.min(-1)), cardiac output (Q, 25+/-5 vs 22.5+/-3.3 L.min(-1)), stroke volume (SV, 134+/-37 vs 121+/-22 mL.beat(-1)), delivery of oxygen (DO(2), 5+/-.87 vs 3.97+/-.68 L.min(-1)), and hemoglobin concentration (Hb, 153+/-12 vs 135+/-16 gm.L(-1)). No significant changes were observed for heart rate (HR); arteriovenous oxygen difference (a-vO(2) diff), systolic blood pressure (SBP), and diastolic blood pressure (DBP).

CONCLUSIONS

These findings indicate that donating one unit of blood decreased VO2(max) due to the decrease in Q, which resulted from the decrease in SV since HR was unchanged. The lower VO2(max) along with the decrease in DO(2) would be expected to have a negative effect on athletic performance.

Detection and quantification of cocaine metabolites in urine samples from horses administered cocaine

Cocaine is a naturally occurring alkaloid that is commonly abused by human-beings for its psychostimulatory effects. Occasionally, very small concentrations (i.e. <100 ng/mL) of the primary cocaine metabolite, benzoylecgonine (BZE) have been detected in urine collected from horses competing in athletic events. In this study urine samples, collected from four horses following the administration of 2.5 and 20 mg of cocaine sublingually and 50 mg of cocaine intravenously, were analyzed for the presence of cocaine and/or its metabolites by enzyme-linked immunosorbent assay (ELISA) and gas chromatography-mass spectrometry (GC-MS). The results of ELISA analysis of urine samples collected from all four horses suggested the presence of cocaine and/or its metabolites up to 10, 48, and 72 h after administration of 2.5, 20, and 50 mg of cocaine, respectively. The results of GC-MS analysis confirmed the presence of BZE above the limit of quantification (LOQ = 5 ng/mL) in urine samples collected from all four horses for up to 24 h after administration of 2.5 mg of cocaine and for up to 48 h after administration of 20 and 50 mg of cocaine. No obvious behavioral effects or overt alterations of heart rate or rhythm were noted in any of these horses after cocaine administration.

IL-18-binding protein protects against lipopolysaccharide- induced lethality and prevents the development of Fas/Fas ligand-mediated models of liver disease in mice

IL-18-binding protein (IL-18BP) is a natural IL-18 inhibitor. Human IL-18BP isoform a was produced as fusion construct with human IgG1 Fc and assessed for binding and neutralizing IL-18. IL-18BP-Fc binds human, mouse, and rat IL-18 with high affinity (K(D) 0.3-5 nM) in a BIAcore-based assay. In vitro, IL-18BP-Fc blocks IL-18 (100 ng/ml)-induced IFN-gamma production by KG1 cells (EC(50) = 0.3 microg/ml). In mice challenged with an LD(90) of LPS (15 mg/kg), IL-18BP-Fc (5 mg/kg) administered 10 min before LPS blocks IFN-gamma production and protects against lethality. IL-18BP-Fc administered 10 min before LPS blocks IFN-gamma production induced by LPS (5 mg/kg) with ED(50) of 0.005 mg/kg. Furthermore, IL-18BP-Fc (5 mg/kg) abrogates LPS (5 mg/kg)-induced IFN-gamma production even when administered 6 days before LPS but shows no effect when administered 9 or 12 days before LPS. Given 10 min before LPS challenge to mice primed 12 days in advance with heat-killed Propionibacterium acnes, IL-18BP-Fc prevents LPS-induced liver damage and IFN-gamma and Fas ligand expression. Given at the moment of priming with P. acnes, IL-18BP-Fc decreases P. acnes-induced granuloma formation, macrophage-inflammatory protein-1alpha and macrophage-inflammatory protein-2 production and prevents sensitization to LPS. IL-18BP-Fc also prevents Con A-induced liver damage and IFN-gamma and Fas ligand expression as well as liver damage induced by Pseudomonas aeruginosa exotoxin A or by anti-Fas agonistic Ab. In conclusion, IL-18BP can be engineered and produced in recombinant form to generate an IL-18 inhibitor, IL-18BP-Fc, endowed with remarkable in vitro and in vivo properties of binding and neutralizing IL-18.

Metabolic cost of walking with and without a shoe lift on the contralateral foot of an immobilised extended knee

The purpose of the present study was to determine the metabolic cost of walking with and without a shoe-lift on the contralateral foot of an immobilised extended knee. Eight male subjects were randomly allocated and participated in both the treatment (walking with a 2.5 cm shoe-lift) and control (walking without a shoe-lift) conditions. Cardiac output (Q) and related cardiovascular measurements were analysed to determine the effect of a shoe-lift on central (heart rate (HR); stroke volume (SV)) and peripheral (arteriovenous oxygen difference (a-vO2 diff)) components of oxygen consumption (VO2). A metabolic analyser was used to determine VO2 (ml x kg(-1) x min(-1)), which was converted to oxygen cost (ml x kg(-1) x m(-1)). The shoe-lift had no significant (p > 0.05) effect on VO2 or oxygen cost. There were no significant differences in Q, HR, SV, a-vO2 diff, systemic vascular resistance, carbon dioxide production, respiratory exchange ratio, expired ventilation, tidal volume and respiratory rate between the two walking conditions with and without a shoe-lift. These findings demonstrate that a shoe-lift added to the contralateral foot of an immobilised extended knee does not produce clinically important effects on oxygen cost or efficiency during walking.

Effects of a 10-minute back rub on cardiovascular responses in healthy subjects

This study determined the cardiovascular responses to a 10-minute back rub. Twelve healthy, college-age males and females (mean age = 22 years) volunteered to participate as subjects. Using an ABA design, the subjects tested for 10 minutes (Control #1) on a padded plinth lying on one side. During the Treatment period, the back rub was administered, which was followed by Control #2. Oxygen consumption (VO2) was determined via the Medical Graphics CPX/D metabolic analyzer, which also estimated cardiac output (Q) using the CO2 rebreathing (equilibrium) method. A repeated measures ANOVA was performed to statistically compare the cardiovascular responses across the three periods. The back rub, when compared to Control #1, had no significant effect on VO2, but the central and peripheral components of VO2 were changed. Cardiac output was decreased as a result of the decreased stroke volume (SV), as a function of the increased peripheral vascular resistance (PVR). We also found an increase in the extraction of oxygen (a-vO2 diff) in the peripheral tissues. These results indicate that the VO2 response during the back rub was achieved by reciprocal central (SV,Q) and peripheral (a-vO2 diff) adjustments. Following the back rub, (i.e., Control #2 vs. Treatment), the decrease in VO2, VCO2, Ve, and a-vO2 diff appears to indicate that it was effective in inducing relaxation. Since HR, SV, and Q were unchanged, the VO2 response was a result of the decreased a-vO2 diff. Hence, the findings suggest certain positive implications for the health care industry.

Prospective randomized controlled trial of extended-release oxybutynin chloride and tolterodine tartrate in the treatment of overactive bladder: results of the OBJECT Study

OBJECTIVE

To compare the efficacy and tolerability of extended-release oxybutynin chloride and tolterodine tartrate at 12 weeks in participants with overactive bladder.

SUBJECTS AND METHODS

The OBJECT (Overactive Bladder: Judging Effective Control and Treatment) study was a prospective, randomized, double-blind, parallel-group study conducted between March and October 2000 at 37 US study sites. Participants who had between 7 and 50 episodes of urge incontinence per week and 10 or more voids in 24 hours received extended-release oxybutynin, 10 mg/d, or tolterodine, 2 mg twice daily. The outcome measures were the number of episodes of urge incontinence, total incontinence, and micturition frequency at 12 weeks adjusted for baseline.

RESULTS

A total of 315 women and 63 men were randomized and treated, and 332 participants (276 women, 56 men) completed the study. At the end of the study, extended-release oxybutynin was significantly more effective than tolterodine in each of the main outcome measures: weekly urge incontinence (P=.03), total incontinence (P=.02), and micturition frequency episodes (P=.02) adjusted for baseline. Both drugs improved symptoms of overactive bladder significantly from baseline to the end of the study as assessed by the 3 main outcome measures (P<.001). Dry mouth, the most common adverse event, was reported by 28.1% and 33.2% of participants taking extended-release oxybutynin and tolterodine, respectively (P=.32). Rates of central nervous system and other adverse events were low and similar in both groups.

CONCLUSIONS

Extended-release oxybutynin was more effective than tolterodine as measured by end-of-study urge incontinence, total incontinence, and micturition frequency episodes. Both groups had similar rates of dry mouth and other adverse events.

Asn to Lys mutations at three sites which are N-glycosylated in the mammalian protein decrease the aggregation of Escherichia coli-derived erythropoietin

Erythropoietin (EPO) derived from Escherichia coli is unstable to elevated temperature and tends to aggregate with time, making it unsuitable for high-resolution structure analysis. The mammalian EPO contains about 40% carbohydrate, which makes this protein more stable and less prone to aggregate than non-glycosylated E.coli-derived EPO, but makes it unsuitable for high-resolution analysis owing to its size and flexibility. In an attempt to decrease the aggregation of E.coli-derived EPO, the three asparagine residues at positions 24, 38 and 83 were mutated to lysine residues. In the native protein, these residues are the sites of N-linked glycosylation, which suggests that they should be located on the surface of the protein and should not be involved in interactions in the hydrophobic protein core. Therefore, the substitution of basic amino acids for these neutral asparagine residues is not expected to affect the protein structure, but should increase the isoelectric point of the protein and its net positive charge, decreasing its tendency to aggregate at or below neutral pH due to electrostatic interactions. No apparent alterations in receptor binding, as determined by both cell-surface receptor competition assay and in vitro receptor dimerization experiments, were observed when these mutations were introduced into the EPO sequence. However, this mutant protein displayed a significant increase in stability to heat treatment and to storage, relative to the wild-type molecule. This resulted in a greater number of observable cross peaks in the mutant EPO in 2D NOESY experiments. However, the mutant was similar to the wild-type in stability when urea was used as a denaturant. This indicates that the introduced mutations resulted in a decrease in aggregation with heating or with prolonged incubation at ambient temperature, without changing the conformational stability or the receptor binding affinity of the mutant protein. This approach of placing charged residues at sites where N-glycosylation occurs in vivo could be applied to other systems as well.

Cardiovascular responses to laughter: a pilot project

The purpose of this study was to determine cardiovascular responses to laughter. The CO(2) rebreathing method was used to determine cardiac output and understand the role of the central and peripheral components of oxygen consumption and its relation to energy expended. Eight college-age subjects participated in this study. During periods of 5 minutes each, while sitting in a comfortable chair, subjects first rested, then viewed a videotape of a well-known comedian, then remained sitting. A repeated-measures analysis of variance was used to analyze the data. During laughter, there were significant increases in stroke volume and cardiac output and significant decreases in arteriovenous oxygen difference and total peripheral resistance. Following laughter, there was a significant decrease in oxygen consumption.

Characterization of a new human B7-related protein: B7RP-1 is the ligand to the co-stimulatory protein ICOS

Optimal T cell activation requires the interactions of co-stimulatory molecules, such as those in the CD28 and B7 protein families. Recently, we described the co-stimulatory properties of the murine ligand to ICOS, which we designated as B7RP-1. Here, we report the co-stimulation of human T cells through the human B7RP-1 and ICOS interaction. This ligand-receptor pair interacts with a K:(D) approximately 33 nM and an off-rate with a t((1/2)) > 10 min. Interestingly, tumor necrosis factor (TNF)-alpha differentially regulates the expression of human B7RP-1 on B cells, monocytes and dendritic cells (DC). TNF-alpha enhances B7RP-1 expression on B cells and monocytes, while it inhibits it on DC. The human B7RP-1-Fc protein or cells that express membrane-bound B7RP-1 co-stimulate T cell proliferation in vitro. Specific cytokines, such as IFN-gamma and IL-10, are induced by B7RP-1 co-stimulation. Although IL-2 levels are not significantly increased, B7RP-1 co-stimulation is dependent on IL-2. These experiments define the human ortholog to murine B7RP-1 and characterize its interaction with human ICOS.

APRIL and TALL-I and receptors BCMA and TACI: system for regulating humoral immunity

We report that the tumor neurosis factor homolog APRIL (a proliferation-inducing ligand) stimulates in vitro proliferation of primary B and T cells and increases spleen weight due to accumulation of B cells in vivo. APRIL functions via binding to BCMA (B cell maturation antigen) and TACI (transmembrane activator and CAML-interactor) and competes with TALL-I (also called BLyS or BAFF) for receptor binding. Soluble BCMA and TACI specifically prevent binding of APRIL and block APRIL-stimulated proliferation of primary B cells. BCMA-Fc also inhibits production of antibodies against keyhole limpet hemocyanin and Pneumovax in mice, indicating that APRIL and/or TALL-I signaling via BCMA and/or TACI are required for generation of humoral immunity. Thus, APRIL-TALL-I and BCMA-TACI form a two ligands-two receptors pathway involved in stimulation of B and T cell function.

Flt3 ligand structure and unexpected commonalities of helical bundles and cystine knots

Human Flt3 ligand (Flt3L) stimulates early hematopoiesis by activating a type III tyrosine kinase receptor on primitive bone marrow stem cells. The crystal structure of soluble Flt3L reveals that it is a homodimer of two short chain alpha-helical bundles. Comparisons of structure-function relationships of Flt3L with the homologous hematopoietic cytokines macrophage colony stimulating factor (MCSF) and stem cell factor (SCF) suggest that they have a common receptor binding mode that is distinct from the paradigm derived from the complex of growth hormone with its receptor. Furthermore, we identify recognition features common to all helical and cystine-knot protein ligands that activate type III tyrosine kinase receptors, and the closely related type V tyrosine kinase receptors.

Modulation of T-cell-mediated immunity in tumor and graft-versus-host disease models through the LIGHT co-stimulatory pathway

LIGHT was recently described as a member of the tumor necrosis factor (TNF) 'superfamily'. We have isolated a mouse homolog of human LIGHT and investigated its immunoregulatory functions in vitro and in vivo. LIGHT has potent, CD28-independent co-stimulatory activity leading to T-cell growth and secretion of gamma interferon and granulocyte-macrophage colony-stimulating factor. Gene transfer of LIGHT induced an antigen-specific cytolytic T-cell response and therapeutic immunity against established mouse P815 tumor. In contrast, blockade of LIGHT by administration of soluble receptor or antibody led to decreased cell-mediated immunity and ameliorated graft-versus-host disease. Our studies identify a previously unknown T-cell co-stimulatory pathway as a potential therapeutic target.

Protection against the mortality associated with disease models mediated by TNF and IFN-gamma in mice lacking IFN regulatory factor-1

Mortality and cytokine production associated with disease models mediated by TNF- and IFN-gamma were studied in mice lacking IFN regulatory factor-1 (IRF-1). IRF-1 knockout (KO) mice showed no mortality after the injection of a dose of LPS lethal in intact control mice (LD95). KO mice showed lower circulating levels of TNF and IFN-gamma than controls. KO mice also showed lower TNF and IFN-gamma mRNA in the spleen or liver than controls. KO mice had smaller spleens than controls, which contained similar percentage but lower absolute count of macrophages and lower percentage and absolute count of NK cells. IRF-1 KO mice survived longer than controls after the coinjection of LPS and galactosamine. IRF-1 KO mice also showed less mortality than controls after the injection of Con A and in a model of cerebral malaria. After the injection of a lethal dose of TNF (LD88), mortality was similar between KO and intact mice. Mortality was also similar after the coinjection of two nonlethal doses of TNF and IFN-gamma, a lethal combination (LD100). This study shows that the lack of IRF-1 protects against the mortality associated with disease models mediated by TNF and IFN-gamma but has no effect on the mortality directly induced by TNF and IFN-gamma. The lack of IRF-1 appears to result in impaired production of TNF and IFN-gamma, reflecting a down-regulation of gene expression in the liver and spleen as well as a reduction in the number of splenic cells.

Novel neurotrophin-1/B cell-stimulating factor-3: a cytokine of the IL-6 family

We have identified a cytokine of the IL-6 family and named it novel neurotrophin-1/B cell-stimulating factor-3 (NNT-1/BSF-3). NNT-1/BSF-3 cDNA was cloned from activated Jurkat human T cell lymphoma cells. Its sequence predicts a 225-aa protein with a 27-aa signal peptide, a molecular mass of 22 kDa in mature form, and the highest homology to cardiotrophin-1 and ciliary neurotrophic factor. The gene for NNT-1/BSF-3 is on chromosome 11q13. A murine equivalent to NNT-1/BSF-3 also was identified, which shows 96% homology to human NNT-1/BSF-3. NNT-1/BSF-3 mRNA is found mainly in lymph nodes and spleen. NNT-1/BSF-3 induces tyrosine phosphorylation of glycoprotein 130 (gp130), leukemia inhibitory factor receptor beta, and signal transducer and activator of transcription 3 in the SK-N-MC human neuroblastoma cells. NNT-1/BSF-3 shows activities typical of IL-6 family members. In vitro, it supports the survival of chicken embryo motor and sympathetic neurons. In mice, it induces serum amyloid A, potentiates the induction by IL-1 of corticosterone and IL-6, and causes body weight loss and B cell hyperplasia with serum IgG and IgM increase. NNT-1/BSF-3 is a gp130 activator with B-cell stimulating capability.

A chimeric form of osteoprotegerin inhibits hypercalcemia and bone resorption induced by IL-1beta, TNF-alpha, PTH, PTHrP, and 1, 25(OH)2D3

Osteoprotegerin (OPG) is a secreted protein that inhibits osteoclast formation and activity and appears to be a critical regulator of bone mass and metabolism. In the current study, mice were challenged with various cytokines and hormones (interleukin-1beta, tumor necrosis factor-alpha, parathyroid hormone, parathyroid hormone-related protein, and 1alpha,25-dihydroxyvitamin D3) that are known to increase bone resorption and cause hypercalcemia and treated concurrently with either a recombinant chimeric Fc fusion form of human OPG, with enhanced biological activity (cOPG) (2.5 mg/kg/day) or vehicle. Mice receiving these bone-resorbing factors became hypercalcemic by day 3 after commencing treatment and had increased bone resorption as evidenced by elevated osteoclast numbers on day 5. Concurrent cOPG treatment prevented hypercalcemia (p < 0.05) and maintained osteoclast numbers in the normal range (p < 0.001). The demonstration that cOPG can inhibit bone resorption suggests that this molecule may be useful in the treatment of diseases including hyperparathyroidism, humoral hypercalcemia of malignancy, osteoporosis, and inflammatory bone disease, which are characterized, in part, by increases in osteoclastic bone resorption.

Interaction of granulocyte colony-stimulating factor (G-CSF) with its receptor. Evidence that Glu19 of G-CSF interacts with Arg288 of the receptor

Granulocyte colony-stimulating factor (G-CSF) forms a tetrameric complex with its receptor, comprising two G-CSF and two receptor molecules. The structure of the complex is unknown, and it is unclear whether there are one or two binding sites on G-CSF and the receptor. The immunoglobulin-like domain and the cytokine receptor homologous module of the receptor are involved in G-CSF binding, and Arg288 in the cytokine receptor homologous module is particularly important. To identify residues in G-CSF that interact with Arg288, selected charged residues in G-CSF were mutated to Ala. To clarify whether there are two binding sites, a chimeric receptor was created in which the Ig domain was replaced with that of the related receptor gp130. This chimera bound G-CSF but could not transduce a signal, consistent with failure of dimerization and loss of one binding site. The G-CSF mutants had reduced mitogenic activity on cells expressing wild-type receptor. When tested with the chimeric receptor, all G-CSF mutants except one (E46A) showed reduced binding, suggesting that Glu46 is important for interaction with the Ig domain. On cells expressing R288A receptor, all the G-CSF mutants except E19A showed reduced mitogenic activity, indicating that Glu19 of G-CSF interacts with Arg288 of the receptor.

Cardiovascular responses to a hot tub bath

This study was conducted to determine the cardiovascular effects of 15 minutes of hot tub immersion at 39 degrees C. Five college-age subjects (4 males and 1 female) volunteered to participate in this study. Assessments were made while sitting first in a chair for 5 minutes and then in the hot tub for 15 minutes. Oxygen consumption (VO2) and cardiac output (Q) measurements were made using a Medical Graphics CPX/D metabolic analyzer. Cardiac output was determined at minute 15 using the indirect CO2 rebreathing procedure. The data were analyzed using the analysis of variance with repeated measures, which indicated that at minute 15, heart rate (HR) and Q were increased, which increased VO2. The increase in Q was due to the heart rate (HR) response and the decrease in systemic vascular resistance (SVR). Mean arterial pressure (MAP) and systolic blood pressure (SBP) were decreased while double product (DP) was increased. There were no changes in stroke volume (SV) or arteriovenous oxygen difference (a-vO2 diff). These findings indicate that the HR and Q responses are necessary to the increase in metabolism (VO2). Hot tube use within these time and temperature constraints should reduce concern over hot tub safety in college-age subjects.

GFRalpha-2 and GFRalpha-3 are two new receptors for ligands of the GDNF family

The receptor for glial cell line-derived neurotrophic factor (GDNF) consists of GFRalpha-1 and Ret. Neurturin is a GDNF-related neurotrophin whose receptor is presently unknown. Here we report that neurturin can bind to either GFRalpha-1 or GFRalpha-2, a novel receptor related to GFRalpha-1. Both GFRalpha-1 and GFRalpha-2 mediate neurturin-induced Ret phosphorylation. GDNF can also bind to either GFRalpha-1 or GFRalpha-2, and activate Ret in the presence of either binding receptor. Although both ligands interact with both receptors, cells expressing GFRalpha-1 bind GDNF more efficiently than neurturin, while cells expressing GFRalpha-2 bind neurturin preferentially. Cross-linking and Ret activation data also suggest that while there is cross-talk, GFRalpha-1 is the primary receptor for GDNF and GFRalpha-2 exhibits a preference for neurturin. We have also cloned a cDNA that apparently codes for a third member of the GFRalpha receptor family. This putative receptor, designated GFRalpha-3, is closely related in amino acid sequence and is nearly identical in the spacing of its cysteine residues to both GFRalpha-1 and GFRalpha-2. Analysis of the tissue distribution of GFRalpha-1, GFRalpha-2, GFRalpha-3, and Ret by Northern blot reveals overlapping but distinct patterns of expression. Consistent with a role in GDNF function, the GFRalphas and Ret are expressed in many of the same tissues, suggesting that GFRalphas mediate the action of GDNF family ligands in vivo.

Molecular cloning and functional characterization of a novel CC chemokine, stimulated T cell chemotactic protein (STCP-1) that specifically acts on activated T lymphocytes

A novel human chemokine STCP-1 (stimulated T cell chemotactic protein) was isolated from an activated macrophage cDNA library. The chemokine has four cysteines positioned in a manner that identifies STCP-1 as a member of the CC chemokine family. The amino acid sequence shows 34% identity with RANTES. The gene consists of 3 exons and 2 introns with the position of intron/exon boundaries similar to that of RANTES. The gene is expressed as a 3.4-kilobase transcript on lymph node, thymus, and Appendix. STCP-1 induces Ca2+ mobilization in a small percentage of primary activated T lymphocytes, but on repeated stimulation the percentage of T lymphocytes that respond to STCP-1 increases. The chemokine STCP-1 does not induce Ca2+ mobilization in monocytes, dendritic cells, neutrophils, eosinophils, lipopolysaccharide-activated B lymphocytes, and freshly isolated resting T lymphocytes. Similarly, STCP-1, while acting as a mild chemoattractant for primary activated T lymphocytes, is a potent chemoattractant for chronically activated T lymphocytes but has no chemoattractant activity for monocytes, neutrophils, eosinophils, and resting T lymphocytes. As STCP-1 acts specifically on activated T lymphocytes, it may play a role in the trafficking of activated/effector T lymphocytes to inflammatory sites and other aspects of activated T lymphocyte physiology.

Osteoprotegerin: a novel secreted protein involved in the regulation of bone density

A novel secreted glycoprotein that regulates bone resorption has been identified. The protein, termed Osteoprotegerin (OPG), is a novel member of the TNF receptor superfamily. In vivo, hepatic expression of OPG in transgenic mice results in a profound yet nonlethal osteopetrosis, coincident with a decrease in later stages of osteoclast differentiation. These same effects are observed upon administration of recombinant OPG into normal mice. In vitro, osteoclast differentiation from precursor cells is blocked in a dose-dependent manner by recombinant OPG. Furthermore, OPG blocks ovariectomy-associated bone loss in rats. These data show that OPG can act as a soluble factor in the regulation of bone mass and imply a utility for OPG in the treatment of osteoporosis associated with increased osteoclast activity.

Effects of assistive devices on cardiorespiratory demands in older adults

BACKGROUND AND PURPOSE

The purpose of this study was to quantify and compare cardiorespiratory demands imposed during unassisted ambulation and ambulation with various assistive devices in older adults.

SUBJECTS

Ten volunteers (3 male, 7 female) who were not dependent on assistive devices for ambulation, with a mean age 60.3 years (SD = 8.4, range = 50-74), participated.

METHODS

Immediately after a 5-minute steady-state session with each of the assistive devices tested (standard walker, wheeled walker, and single-point cane), subjects ambulated for 2 minutes at a self-selected speed with each device and unassisted while selected cardiorespiratory and metabolic variables were monitored.

RESULTS

Ambulation with the use of a standard walker was shown to require 212% more oxygen per meter than unassisted ambulation and 104% more oxygen per meter than ambulation with a wheeled walker. Ambulation with a standard walker elicited 200% and 98% higher heart rate per meter as compared with unassisted ambulation and ambulation with a wheeled walker, respectively. No difference was detected for physiologic demands between unassisted ambulation and ambulation with a cane.

CONCLUSION AND DISCUSSION

The decision to prescribe a wheeled walker versus a standard walker may be clinically important with patients who have impaired cardiorespiratory systems.

Refined crystal structure and mutagenesis of human granulocyte-macrophage colony-stimulating factor

The crystal structure of recombinant human granulocyte-macrophage colony stimulating factor (rhGM-CSF) has been refined against data extending to a resolution of approximately 2.4 A along a* and approximately 1.9 A along b* and c*. Anisotropic scale factors of B11 = -20.8 A2, B22 = 7.4 A2, B33 = 13.3 A2 corrected for the more rapid fall of diffraction in the a* direction. The anisotropy correlates with the weak crystal packing interactions along the a axis. In addition to apolar side chains in the protein core, there are 10 buried hydrogen bonding residues. Those residues involved in intramolecular hydrogen bonding to main chain atoms are better conserved than those hydrogen bonding to other side chain atoms; 24 solvation sites are observed at equivalent positions in the two molecules in the asymmetric unit, and the strongest among these are located in clefts between secondary structural elements. No buried water sites are seen. Two surface clusters of hydrophobic side chains are located near the expected receptor binding regions. Mutagenesis of 11 residues on the helix A/helix C face confirms the importance of Glu-21 and shows that Gly-75 and Gln-86, located on helix C, each cause a greater than fourfold drop in activity. Glu-21 and Gly-75, but not Gln-86, are structurally equivalent to residues involved in the growth hormone binding to its receptor.

Preparative electrofocusing for industrial applications

This paper presents a case study of using a multicompartment isoelectric focusing apparatus to determine the isoelectric points and focus preparative quantities of brain derived neurotrophic factor (BDNF) and neurotrophic factor 3 (NT3). A separation of PEGylated from unPEGylated forms of granulocyte colony stimulating factor (G-CSF) is described as well. Both BDNF and NT3 have substantially higher pI values in this system than is predicted from sequenced based modeling. Although PEGylated forms of G-CSF can be separated from the unPEGylated forms, separation of protein with differing degrees of PEGylation was not achieved. The paper additionally demonstrates that this technique can be used simultaneously as an analytical and preparative tool, eliminating the need for analytical IEF gels.

Cloning and expression of the gene encoding a novel proteinase from Tritirachium album limber

We have isolated the cDNA and the genomic clones encoding a novel serine proteinase, named proteinase T, from the fungus Tritirachium album Limber. The coding region of the gene is interrupted by two introns. The amino acid sequence of proteinase T as deduced from the nucleotide sequence is about 56% identical to that of proteinase K. Four cysteines are present in the mature proteinase, probably in the form of disulfide bonds. We have also purified the native proteinase from Tritirachium album Limber grown in the presence of 2% skim milk. Proteinase T is extremely stable at 50 degrees C. The thermal stability is not affected in the presence of 1% SDS either at pH 8.0 or 10.0. We have expressed the cDNA of proteinase T in Escherichia coli. The authenticity of the proteinase has been characterized by Western blotting and amino terminal analysis of the recombinant product. High level expression of proteinase T in E. coli as well as the refolding process to generate active proteinase will be discussed in detail.

Pegylated megakaryocyte growth and development factor abrogates the lethal thrombocytopenia associated with carboplatin and irradiation in mice

Megakaryocyte growth and development factor (MGDF) is a potent inducer of megakaryopoiesis in vitro and thrombopoiesis in vivo. The effects of MGDF appear to be lineage-selective, making this cytokine an ideal candidate for use in alleviating clinically relevant thrombocytopenias. This report describes a murine model of life-threatening thrombocytopenia that results from the combination treatment of carboplatin and sublethal irradiation. Mortality of this regimen is 94% and is associated with widespread internal bleeding. The daily administration of pegylated recombinant human MGDF (PEG-rMGDF) significantly reduced mortality (to < 15%) and ameliorated the depth and duration of thrombocytopenia. The severity of leucopenia and anemia was also reduced, although it was not clear whether these effects were direct. Platelets generated in response to PEG-rMGDF were morphologically indistinguishable from normal platelets. PEG-rMGDF administered in combination with murine granulocyte colony-stimulating factor completely prevented mortality and further reduced leukopenia and thrombocytopenia. These data support the concept that PEG-rMGDF may be useful to treat iatrogenic thrombocytopenias.

Inhibition of granulocyte-macrophage colony-stimulating factor (GM-CSF) activity by suramin and suramin analogues is correlated to interaction with the GM-CSF nucleotide-binding site

Suramin and suramin analogues strongly inhibit both nucleotide interaction with the nucleotide-binding site of granulocyte-macrophage colony-stimulating factor (GM-CSF) and bioactivity of the molecule as assessed by competition photoaffinity labeling and cell proliferation assay, respectively. The half-maximal inhibition of cell proliferation by suramin occurs at 68 +/- 2.5 microM; three suramin analogues achieved comparable activity. The degree of competitive inhibition of nucleotide-binding by these compounds and the inhibition of GM-CSF bioactivity are correlated such that the compounds show similar rank-order by both of these methods. The strong interaction of suramin and related compounds with the nucleotide-binding site may mimic nucleotide-mediated inhibition of GM-CSF bioactivity and may be an important mechanism by which suramin acts as a pharmacological anti-growth factor agent.

Effects of sexual intercourse on maximal aerobic power, oxygen pulse, and double product in male sedentary subjects

It is well known that athletes in the United States are told to abstain from sexual intercourse prior to athletic competition. The rationale for such a policy appears to be related to the hypothesis that sexual intercourse decreases the athletes' ability to perform efficiently and/or maximally. But the effect that sexual intercourse may have on exercise performance has not been examined widely. Very likely, the restrictions placed on athletes have little to do with the athletes' physiological ability to substain a particular exercise intensity and/or perform maximally. The purpose of this study was to determine the effects of sexual intercourse 12 hours prior to maximal treadmill exercise on aerobic power, oxygen pulse, and double product (i.e., an index of relative cardiac work). Eleven male subjects were tested on the treadmill with and without prior sexual intercourse. The results from the maximal exercise tests showed that aerobic power, oxygen pulse, and double product were not different. Therefore, the data suggest that it is justified to dismiss the point of view that sexual intercourse decreases maximal exercise performance.

Thrombocytopenia in dogs induced by granulocyte-macrophage colony-stimulating factor: increased destruction of circulating platelets

Administration of recombinant canine granulocyte-macrophage colony-stimulating factor (rcGM-CSF) to normal dogs in previous studies induced an increase in peripheral blood neutrophils and a dose-dependent decrease in platelet counts. In six dogs that received the highest tested dose of rcGM-CSF (50 micrograms/kg/d) for a minimum of 12 days, the mean nadir of the platelet count was 46,000/microL (range, 4,000 to 91,000/microL) on day 9 +/- 1.1 after starting therapy, compared with a mean baseline platelet count of 398,000/microL (range, 240,000 to 555,000/microL). In three dogs, survival of autologous 111In-labeled platelets was reduced from a mean of 4.9 days to 1.3 days during the administration of rcGM-CSF. Biodistribution studies with gamma camera imaging indicated that there was an increase in mean hepatic uptake during the administration of rcGM-CSF, from 15% to 44% of the total injected 111In-labeled platelets at 2 hours, whereas splenic uptake was not significantly changed. In contrast, in two evaluable dogs who were recipients of 111In-labeled platelets from matched allogeneic donors receiving rcGM-CSF, platelet survival was not reduced and no increased hepatic uptake was noted. A third dog became alloimmunized to the matched donor platelets and was not evaluable. Immunohistologic studies of liver and spleen were performed with monoclonal antibodies specific for canine gpIIb/IIIa and P-selectin in dogs treated with rcGM-CSF and compared with untreated controls. On treatment, a marked reduction of platelets in the red pulp of the spleen was evident, and in general, the presence of platelet antigen in the liver was unchanged. Therefore, platelets were not being sequestered, but destroyed in the liver and spleen. The platelet antigens, P-selectin and gpIIb/IIIa, were identified in association with Kupffer cells in the liver, but no difference in the number of distribution of these Kupffer cells was found between controls and rcGM-CSF-treated dogs. In the spleen during rcGM-CSF treatment, most platelet antigens were associated with large mononuclear cells in the marginal zone. During administration of rcGM-CSF, CD1c and CD11c expression was increased on Kupffer cells. Platelet P-selectin expression and binding of leukocytes to circulating platelets were unchanged from baseline studies with rcGM-CSF treatment. In conclusion, during the administration of rcGM-CSF to dogs, a local process in the liver and spleen is induced resulting in thrombocytopenia.(ABSTRACT TRUNCATED AT 400 WORDS)

Influence of a 36-h fast on the central and peripheral components of VO2 during submaximal exercise and peak oxygen uptake

To determine if a 36-h fast affects the central and peripheral components of VO2 during submaximal exercise and peak oxygen uptake (VO2 peak), 10 physically healthy males exercised first for 10 min at approximately 60% of their VO2 peak and then to fatigue. Their cardiovascular responses were compared with those of 10 physically healthy controls (males) who were individually matched by VO2 peak values. Fasting had no significant effect on the central (heart rate, HR; stroke volume, SV; cardiac output, Q) and peripheral (arteriovenous oxygen content difference, a-vO2 diff.) components of VO2 during submaximal exercise. The respiratory exchange ratio (RER) during submaximal exercise was significantly decreased in the fasted subjects. Based on the RER, fasting altered substrate utilization of the muscle and thereby increased the contribution of fat during submaximal exercise. Fasting had no significant effect on VO2 peak, HR or O2 pulse, but RER was significantly lower during incremental exercise to fatigue. These results demonstrate that VO2 during submaximal exercise in fasted subjects is achieved by similar central and peripheral responses as found in non-fasted subjects, and that fasting does not reduce VO2 peak.

Effects of the obese gene product on body weight regulation in ob/ob mice

C57BL/6J mice with a mutation in the obese (ob) gene are obese, diabetic, and exhibit reduced activity, metabolism, and body temperature. Daily intraperitoneal injection of these mice with recombinant OB protein lowered their body weight, percent body fat, food intake, and serum concentrations of glucose and insulin. In addition, metabolic rate, body temperature, and activity levels were increased by this treatment. None of these parameters was altered beyond the level observed in lean controls, suggesting that the OB protein normalized the metabolic status of the ob/ob mice. Lean animals injected with OB protein maintained a smaller weight loss throughout the 28-day study and showed no changes in any of the metabolic parameters. These data suggest that the OB protein regulates body weight and fat deposition through effects on metabolism and appetite.

Recombinant human megakaryocyte growth and development factor stimulates thrombocytopoiesis in normal nonhuman primates

Megakaryocyte growth and development factor (MGDF) is a novel cytokine that binds to the c-mpl receptor and stimulates megakaryocyte development in vitro and in vivo. This report describes the ability of recombinant human (r-Hu) MGDF to affect megakaryocytopoiesis in normal nonhuman primates. r-HuMGDF was administered subcutaneously to normal, male rhesus monkeys once per day for 10 consecutive days at dosages of 2.5, 25, or 250 micrograms/kg of body weight. Bone marrow and peripheral blood were assayed for clonogenic activity and peripheral blood counts were monitored. Circulating platelet counts increased significantly (P < .05) for all doses within 6 days of r-HuMGDF administration and reached maximal levels between day 12 and day 14 postcytokine administration. The 2.5, 25.0, and 250.0 micrograms/kg/d doses elicited peak mean platelet counts that were 592%, 670%, and 449% of baseline, respectively. Bone marrow-derived clonogenic data showed significant increases in the concentration of megakaryocyte (MEG)-colony-forming unit (CFU) and granulocyte-erythroid-macrophage-megakaryocyte (GEMM)-CFU, whereas that of granulocyte-macrophage (GM)-CFU and burst-forming unit-erythroid (BFU-e) remained unchanged during the administration of r-HuMGDF. These data show that r-HuMGDF is a potent stimulator of thrombocytopoiesis in the normal nonhuman primate.

Identification of N-terminus peptide of human granulocyte/macrophage colony stimulating factor as the site of nucleotide interaction

The interaction of nucleotides with recombinant human granulocyte/macrophage colony stimulating factor (rhGM-CSF) has been investigated. Utilizing nucleotide photoaffinity probes [gamma 32P]-8N3ATP and [beta 32P]-8N3Ap4A, an analog of alarmone, the specificity of interaction was demonstrated by saturation of photoinsertion by these analogs and protection of photoinsertion by these analogs in the presence of natural nucleotide. The site of photoinsertion was tentatively determined to be Ser9. The photolabeled cytokine has lost most of its biological activity in a cellular proliferation assay, indicating a possible physiological role for this interaction.

The effect of massage on oxygen consumption at rest

This study determined the effect of massage on oxygen consumption at rest. Ten healthy, adult males (mean age = 28 years) volunteered to serve as subjects. During the Control Session, each subject was placed in the supine position on a massage table to remain motionless for 30 minutes. During the Treatment Session, each subject received a 30-minute sports massage of the lower extremities. Oxygen consumption was determined via the Beckman Metabolic Measurement Cart, which was upgraded to estimate cardiac output using the CO2 rebreathing (equilibrium) method. Paired t-tests were used for all tests of statistical significance. There was no significant difference in the subjects' oxygen consumption with the massage. Also, there were no significant differences in heart rate, stroke volume, cardiac output, and arteriovenous oxygen difference during the massage. These findings indicate (1) that massaging the lower extremities results in neither an increase nor a decrease in the subjects' expenditure of energy at rest and (2) that the energy cost of metabolism at rest is determined by the same central and/or peripheral adjustments.

Effect of recombinant canine granulocyte-macrophage colony-stimulating factor on hematopoietic recovery after otherwise lethal total body irradiation

Recombinant canine granulocyte-macrophage colony-stimulating factor (rcGM-CSF) was studied in normal dogs and in dogs receiving otherwise lethal total body irradiation (TBI) without marrow transplant. Five normal dogs receiving 25 micrograms/kg of rcGM-CSF by subcutaneous (SC) injection twice daily (BID) for 14 days showed increases in peripheral blood neutrophil counts of three to five times the baseline. Platelet counts decreased during administration of rcGM-CSF to a mean nadir of 52,800. Ten dogs received 400 cGy TBI at 10 cGy/min from two opposing 60Co sources and no marrow graft. Within 2 hours of TBI, rcGM-CSF was begun at a dose of 50 micrograms/kg SC BID for 5 doses and then continued at 25 micrograms/kg SC BID for 21 days. Only 1 of the 10 dogs receiving rcGM-CSF survived with complete and sustained recovery of hematopoiesis. One of 13 historical control dogs survived after 400 cGy with no hematopoietic growth factor or marrow infusion. Results with rcGM-CSF were compared with previous and concurrent data with G-CSF studied in the same model. Of 10 dogs receiving G-CSF, 8 survived with complete and sustained hematopoietic recovery, a significantly better survival than that seen with rcGM-CSF (P = .006). Neutrophil counts were sustained at higher levels after TBI for the first 18 days in the G-CSF group (P < .016) and the neutrophil nadirs were higher. No differences in neutrophil nadirs were noted between the rcGM-CSF and control groups. Dogs treated with rcGM-CSF experienced a more rapid decline of platelet counts than G-CSF-treated or control dogs over the first 18 days (P < .001). The nadir of the platelet count was higher in the control group than in either the G-CSF or rcGM-CSF group and no significant difference was observed between the G-CSF and rcGM-CSF groups. After otherwise lethal TBI (400 cGy) in dogs, rcGM-CSF was not effective in promoting hematopoietic recovery or improving survival.

Phase I trial of intravenous and intraperitoneal administration of granulocyte-macrophage colony-stimulating factor

To assess the toxicity, pharmacokinetics, and local and systemic effects of the intraperitoneal (i.p.) administration of granulocyte-macrophage colony-stimulating factor (GM-CSF) at various dosages, 13 patients with predominantly i.p. malignancies refractory to standard chemotherapy were studied. GM-CSF was administered intravenously (i.v.) for 5 consecutive days; 21 days later the same dosage of GM-CSF was administered i.p. for 5 consecutive days. Four dosage levels were studied: 1, 2, 4, and 8 micrograms/kg/day. GM-CSF was well tolerated after i.v. and i.p. administration at doses up to 8 micrograms/kg/day. A transient fall followed by an elevation of circulating white cells was observed over a 24-h period after both i.v. and i.p. GM-CSF administration (mean minimum +/- SE as % baseline): 38 +/- 8% at 30 min after i.v. administration, 21 +/- 5% at 60 min after i.p. administration; mean maximum: 220 +/- 41% at 6 h after i.v. administration, 202 +/- 39% at 12 h after i.p. administration). The magnitude and time course of these changes were very similar for the two routes despite an up to 400-fold difference in serum GM-CSF levels at the same time points. Changes in leukocyte count and differential and neutrophil function were also similar over the 3-week period after both i.v. and i.p. administration. In the only patient who had i.p. GM-CSF levels assayed, i.p. administration achieved high levels of GM-CSF in peritoneal fluid (Cmax 343 ng/ml) with maintenance of high concentrations over 24 h (C24h 128 ng/ml).(ABSTRACT TRUNCATED AT 250 WORDS)

Crystallization and preliminary X-ray analysis of leukemia inhibitory factor

Leukemia inhibitory factor (LIF) is a polyfunctional molecule with significant and diverse biological activities. LIF is a glycoprotein secreted by a number of different cell types in vitro. It is induced in fibroblasts, lymphocytes, monocytes and astrocytes by various inducers such as serum, TNF, interleukin-IP and EGF. Due to extensive and variable glycosylation the molecular weight can range from 38 to 67 kDA. The biological functions of LIF are mediated through a receptor and a signal transducer, gp130, which is also used by factors like interleukin-6 (IL-6), cilliary neurotropic factor (CNTF), and oncostatin M (OSM). Here, we report the crystallization of the non-glycosylated human-like LIF expressed in E. coli. The present crystals diffract to 2.0 A using synchrotron radiation. They belong to the monoclinic space group C2, and the cell dimensions are a = 61.5 A, b = 45.3 A, c = 77.7 A and beta = 112.3 degrees.

Sites of iodination in recombinant human brain-derived neurotrophic factor and its effect on neurotrophic activity

Recombinant human brain-derived neurotrophic factor (BDNF) is now under extensive investigation because of its potential clinical applications. Radioactively labeled proteins are usually required to study receptor binding and pharmacokinetic properties of proteins. This study was undertaken to see if iodination affects the biological and conformational properties of a recombinant BDNF. BDNF was iodinated using a stoichiometric amount of nonradioactive cold NaI to minimize multiple iodinations. Of the four tyrosines present in BDNF--Tyr-52, Tyr-54, Tyr-63, and Tyr-86--only Tyr-63 and Tyr-86 were iodinated under the experimental conditions used. Iodination of Tyr-63 resulted in modification without alteration of the biological activity, whereas iodination of Tyr-86 resulted in a molecule with highly compromised biological activity. Similar inactivation was observed if both Tyr-63 and Tyr-86 were iodinated. These modified proteins exhibited conformation and dimerization apparently identical to those of the native protein, as demonstrated by analytical ultracentrifugation, gel filtration, light scattering, and circular dichroism. From these results, we concluded that Tyr-52 and Tyr-54 are not accessible to the reagent and are probably buried in the hydrophobic core, whereas Tyr-63 and Tyr-86 are exposed on the surface of the molecule; of the two exposed residues, only Tyr-86 contributes to the biological activity.

Comparison of the biophysical characteristics of human brain-derived neurotrophic factor, neurotrophin-3, and nerve growth factor

The structural properties of human brain-derived neurotrophic factor (BDNF) and neurotrophin-3 (NT-3) were studied using sedimentation equilibrium and circular dichroism (CD), fluorescence and Fourier-transform infrared spectroscopies, and compared with those of human nerve growth factor (NGF). Both the far UV CD and infrared spectra indicate that these three proteins have similar, but not identical, secondary structures which contain primarily beta-sheet and irregular structures. NGF appears to contain the most beta-sheet while NT-3 contains a small fraction of alpha-helix. The near UV CD spectra appear to indicate that the three proteins contain disulfide bonds in similar environments, suggesting a resemblance in tertiary structure. The fluorescent tryptophans found in the molecules are relatively solvent exposed, while Trp102 found only in NT-3 is possibly quenched. The fluorescent Trp(s) in NGF are significantly quenched relative to those in the other two neurotrophic factors. Both NT-3 and BDNF have very hydrophilic surfaces at neutral pH, as indicated by a low binding affinity to a hydrophobic probe, anilinonaphthalenesulfonate. Sedimentation equilibrium showed that BDNF, NT-3, and NGF exist as strongly associated dimers in phosphate-buffered saline, pH 7.1. Fits of the observed fringe displacements to various association models suggested that the BDNF, NT-3, and NGF samples contain, in addition to the principal dimeric species, some oligomers, and that NT-3 contains a small fraction of incompetent monomer.

Effects of qigong on cardiorespiratory changes: a preliminary study

Qigong, a special form of breathing exercise, was investigated to examine its effect on cardiorespiratory changes. Ten volunteers (five males and five females) participated in a 20-minute group instructional session for 10 consecutive days before testing of its treatment effects. The testing protocol followed a C1-T-C2 design, where C1, T, and C2 represented the first, treatment, and second control period, respectively. Each period consisted of a 5-minute interval, and thus each testing session consisted of 15 minutes. The results indicated there were no statistically significant differences (p > 0.05) in heart rate or tidal volume for the three 5-minute periods. There was a significant decrease (p < 0.05) in respiratory exchange ratio between T and C2. A significant increase in ventilatory efficiency for carbon dioxide production was found between C1 and T. Statistically significant differences (p < 0.05) were found in the volume of oxygen consumed and carbon dioxide produced, frequency of breath, expired ventilation, and ventilatory efficiency for oxygen produced between the T and the two control periods. This preliminary study of Qigong demonstrates that the subjects were able to learn the technique in a short period of time. The data also suggest that, with an improvement of nearly 20% in ventilatory efficiency for oxygen uptake and carbon dioxide production, this technique may have useful therapeutic value.

Hematologic and bone marrow changes after short- and long-term administration of two recombinant bovine granulocyte colony-stimulating factors

Colony-stimulating factors are a category of glycoproteins that are instrumental in the regulation of hematopoiesis and inflammation. This investigation documented the clinical bone marrow and peripheral blood responses to short-term and long-term administration of a recombinant bovine granulocyte colony-stimulating factor (rb-GCSF) and an analog, where the cysteine at position 17 was substituted with a serine (rb-GCSF ser17). The colony-stimulating factors produced the expected changes in the hematologic findings of the bovine subjects in the study, and there was a cell-specific response to the compounds. The sustained neutrophilia in the long-term study indicates that the bovine species can tolerate the administration of recombinant forms of bovine GCSF for extended periods of time without detectable adverse side effects. The neutrophils from the short-term study revealed no apparent fluctuation, either as enhanced or reduced capability to reduce nitro blue tetrazolium as compared to pretreatment neutrophils. The administration of both recombinant forms of GCSF produced large increases in the bone marrow myeloid:erythroid (M:E) ratio concomitantly with the neutrophilias. This is the first preliminary report documenting the bone marrow response of cattle to the native and recombinant (rb-GCSF ser17) forms of bovine GCSF.

Identification and characterization of a nucleotide binding site on recombinant murine granulocyte/macrophage-colony stimulating factor

Granulocyte/macrophage-colony stimulating factor (GM-CSF) is a regulatory cytokine important in the proliferative and functional activation of hematopoietic cells. It belongs to a family of 20 kDa or less acidic glycoprotein molecules found in a broad range of cellular sources. On the basis of the previously reported nucleotide-binding properties of interleukin-2 (IL-2), atrial natriuretic factor (ANF), and glucagon, the interaction of GM-CSF with nucleotides was investigated. Using radiolabeled 8-azidoadenosine-containing photoprobes of ATP ([gamma-32P]-8N3ATP) and Ap4A, the putative biological alarmone ([beta'-32P]-8N3Ap4A), we have identified a nucleotide binding site on recombinant murine GM-CSF (rmGM-CSF). Specificity of binding was demonstrated by saturation and competition experiments. Saturation of photoinsertion by [gamma-32P]-8N3ATP and [beta'-32P]-8N3Ap4A occurs with apparent Kd's of 10 and 0.7 microM, respectively. Using an immobilized Fe3+ affinity chromatography technique, developed specifically for the isolation of photolabeled peptides, a single radiolabeled peptide was isolated. It was identified as amino acids 5-14 near the N-terminus of GM-CSF. This peptide region has been shown in previous studies to be critical for biological activity. Also consistent with this observation is our finding that the photolabeled GM-CSF has lost most, if not all, of its biological activity, as determined by a cellular proliferation assay.

Role of glycosylation on the secretion and biological activity of erythropoietin

The erythropoietin (EPO) molecule contains four carbohydrate chains. Three contain N-linkages to asparagines at positions 24, 38, and 83, and one contains an O-linkage to a serine at position 126. We constructed human EPO variants that eliminated the three N-glycosylation sites by replacing the asparagines with glutamines singly or in combination. The O-linked carbohydrate chain was removed by replacing the serine with glutamine, valine, histidine, or alanine. A variant with a double mutation (Gln38,83) and another with a triple mutation (Gln24,38,83) were secreted poorly from COS1 and CHO cells even though RNA encoding these variants was present. All other variants with mutations in N-linked glycosylation sites were secreted normally. Removal of any of the N-glycosylation sites reduced the in vivo but not the in vitro biological activity of the EPO molecule. All the mutations at Ser126, the O-glycosylation site, were secreted normally. In vitro activity was also unaffected except for Ala126 which had a 50-fold decrease. The Val126 variant was tested in vivo, and its specific activity was only slightly less than that of the native EPO, which indicates that the O-linked carbohydrate is not essential for activity.