Limits on extra dimensions and new particle production in the exclusive photon and missing energy signature in pp collisions at square root [s]=1.8 TeV

The exclusive gammaE(T) signal has a small standard model cross section and is thus a channel sensitive to new physics. This signature is predicted by models with a superlight gravitino or with large extra spatial dimensions. We search for such signals at the Collider Detector at Fermilab, using 87 pb(-1) of data at square root [s]=1.8 TeV, and extract 95% C.L. limits on these processes. A limit of 221 GeV is set on the scale |F|(1/2) in supersymmetric models. For 4, 6, and 8 extra dimensions, model-dependent limits on the fundamental mass scale M(D) of 0.55, 0.58, and 0.60 TeV, respectively, are found. We also specify a "pseudo-model-independent" method of comparing the results to theoretical predictions.

Search for new physics in photon-lepton events in pp collisions at sqrt[s] = 1.8 TeV

We present the results of a search in pp collisions at sqrt[s] = 1.8 TeV for anomalous production of events containing a photon and a lepton (e or mu), both with large transverse energy, using 86 pb(-1) of data collected with the Collider Detector at Fermilab during the 1994-1995 collider run at the Fermilab Tevatron. The presence of large missing transverse energy (E(T)), additional photons, or additional leptons in these events is also analyzed. The results are consistent with standard model expectations, with the possible exception of photon-lepton events with large E(T), for which the observed total is 16 events and the expected mean total is 7.6+/-0.7 events.

Upsilon production and polarization in p p macro collisions at square root of s = 1.8 TeV

We report on measurements of the Upsilon(1S), Upsilon(2S), and Upsilon(3S) differential cross sections (d(2)sigma/dp(T)dy)(/y/<0.4), as well as on the Upsilon(1S) polarization in p p macro collisions at square root of s = 1.8 TeV using a sample of 77+/-3 pb(-1) collected by the collider detector at Fermilab. The three resonances were reconstructed through the decay Upsilon-->mu(+)mu(-). The measured angular distribution of the muons in the Upsilon(1S) rest frame is consistent with unpolarized meson production.

Diffractive dijet production at sqrt[s] = 630 and 1800 GeV at the Fermilab Tevatron

We report a measurement of the diffractive structure function F(D)(jj) of the antiproton obtained from a study of dijet events produced in association with a leading antiproton in pp collisions at sqrt[s] = 630 GeV at the Fermilab Tevatron. The ratio of F(D)(jj) at sqrt[s] = 630 GeV to F(D)(jj) obtained from a similar measurement at sqrt[s] = 1800 GeV is compared with expectations from QCD factorization and other theoretical predictions. We also report a measurement of the xi ( x-Pomeron) and beta ( x of parton in Pomeron) dependence of F(D)(jj) at sqrt[s] = 1800 GeV. In the region 0.035<xi<0.095, /t/<1 GeV2, and beta<0.5, F(D)(jj)(beta,xi) is found to be of the form beta(-1.0+/-0.1)xi(-0.9+/-0.1), which obeys beta-xi factorization.

Search for new heavy particles in the WZ0 final state in pp collisions at square root[s] = 1.8 TeV

We present the first general search for new heavy particles, X, which decay via X --> WZ0 --> e(nu)+jj as a function of M(X) and Gamma(X) in pp collisions at square root[s] = 1.8 TeV. No evidence is found for production of X in 110 pb(-1) of data collected by the Collider Detector at Fermilab. General cross section limits are set at the 95% C.L. as a function of mass and width of the new particle. The results are further interpreted as mass limits on the production of new heavy charged vector bosons which decay via W' --> WZ0 in an extended gauge model as a function of the width, Gamma(W'), and mixing factor between the W' and the standard model W bosons.

Study of B0 --> J/psiK(*)0pi(+)pi(-) decays with the collider detector at Fermilab

We report a study of the decays B0 --> J/psiK(*)0pi(+)pi(-), which involve the creation of a uu or dd quark pair in addition to a b -->c(cs) decay. The data sample consists of 110 pb(-1) of pp collisions at square root[s] = 1.8 TeV collected by the CDF detector at the Fermilab Tevatron collider during 1992-1995. We measure the branching fractions to be B(B0 --> J/psiK(*0)pi(+)pi(-)) = (6.6 +/- 1.9 +/- 1.1)x10(-4) and B(B0 --> J/psiK0pi(+)pi(-)) = (10.3 +/- 3.3 +/- 1.5)x10(-4). Evidence is seen for contributions from psi(2S)K(*)0, J/psiK0rho(0), J/psiK(*+)pi(-), and J/psiK1(1270).

Search for gluinos and scalar quarks in pp collisions at square root[s] = 1.8 TeV using the missing energy plus multijets signature

We have performed a search for gluinos (g) and scalar quarks (q) in a data sample of 84 pb(-1) of pp collisions at square root[s] = 1.8 TeV, recorded by the Collider Detector at Fermilab. We investigate the final state of large missing transverse energy and three or more jets, a characteristic signature in R-parity-conserving supersymmetric models. The analysis has been performed "blind," in that the inspection of the signal region is made only after the predictions from standard model backgrounds have been calculated. Comparing the data with predictions of constrained supersymmetric models, we exclude gluino masses below 195 GeV/c2 (95% C.L.), independent of the squark mass. For the case m(q) approximately m(g), gluino masses below 300 GeV/c2 are excluded.

Measurement of the strong coupling constant from inclusive jet production at the Tevatron pp collider

We report a measurement of the strong coupling constant, alpha(s)(MZ), extracted from inclusive jet production in pp collisions at square root[s] = 1800 GeV. The QCD prediction for the evolution of alpha(s) with jet transverse energy ET is tested over the range 40<ET<450 GeV using ET for the renormalization scale. The data show good agreement with QCD in the region below 250 GeV. The value of alpha(s) at the mass of the Z0 boson averaged over the range 40<ET<250 GeV is found to be alpha(s)(MZ) = 0.1178+/-0.0001(stat)+0.0081(-0.0095)(expt. syst). The associated theoretical uncertainties are mainly due to the choice of renormalization scale ((+6%)(-4%)) and input parton distribution functions (5%).

Search for gluinos and squarks using like-sign dileptons in pp macro collisions at square root of s = 1.8 TeV

We present results of the first search for like-sign dilepton ( e(+/-)e(+/-), e(+/-)mu(+/-), mu(+/-)mu(+/-)) events associated with multijets and large missing energy using 106 pb(-1) of data in pp macro collisions at square root of s = 1.8 TeV collected during 1992-1995 by the CDF experiment. Finding no events that pass our selection, we examine pair production of gluinos (tilde g) and squarks (tilde q) in a constrained framework of the minimal supersymmetric standard model. At tan beta = 2 and mu = -800 GeV/c(2), we set 95% confidence level limits of M(tilde g)>221 GeV/c(2) for M(tilde g) approximately M(tilde q), and M(tilde q)>168 GeV/c(2) for M(tilde q)>>M(tilde g), both with small variation as a function of mu.

Observation of diffractive J/psi production at the Fermilab Tevatron

We report the first observation of diffractive J/psi(--> mu+mu-) production in pp collisions at root square[s] = 1.8 TeV. Diffractive events are identified by their rapidity gap signature. In a sample of events with two muons of transverse momentum p(mu)T>2 GeV/c within the pseudorapidity region /eta/ < 1.0, the ratio of diffractive to total J/psi production rates is found to be R(J/psi) = [1.45 +/- 0.25]%. The ratio R(J/psi)(x) is presented as a function of x-Bjorken. By combining it with our previously measured corresponding ratio R(jj)(x) for diffractive dijet production, we extract a value of 0.59 +/- 0.15 for the gluon fraction of the diffractive structure function of the proton.

Silica-based bioactive glasses modulate expression of bone morphogenetic protein-2 mRNA in Saos-2 osteoblasts in vitro

A chemical exchange of the silica gel layer forming on the surface of bioactive glasses is thought to be the principal reaction for bone-bioactive glass bonding. The contribution of biological molecules on cell-bioactive glass interaction is largely unknown. To further analyze the mechanisms involved in efficient bone bonding to bioactive glass, Saos-2 osteoblastic cells with proven osteogenic phenotype were cultured for 4, 7 and 14 days on two bioactive glasses with different Si contents. Culture plates and dishes made of bioactive (BAG, 53 % SiO2), biocompatible (BCG, 58% SiO2) and control (GO) glasses were extensively conditioned with phosphate buffer and DMEM medium before seeding the cells. Northern hybridization was used for analysis of mRNA levels of collagen type I (Col-I), alkaline phosphatase (ALP) and bone morphogenetic protein-2 (BMP-2). A significant increase was observed in Col-I mRNA levels in cells grown on the two bioactive glasses when compared with those grown on controls at 4 and 7 days (p < 0.04). The mRNA level for ALP in the cultures of bioactive glasses-made plates and dishes was also increased over control at 7 days (p < 0.02) and remained this way between BAG and G0 at 14 days. Striking differences in BMP-2 mRNA levels existed between BAG and G0 plates and dishes at 7 days (p < 0.05). BMP-2 mRNA level in BAG group was higher than in BCG group at 4, 7 and 14 days, but without statistical significance. Saos-2 osteoblastic cells with strong ALP staining were mostly seen on BAG plates under a light microscope. In confocal microscopy, a bright FITC-stained F-actin ring was present in the cytoplasm of cells grown on BAG dish, demonstrating an active functional status. Stimulation of the expression of BMP-2 and other bone mRNAs by bioactive glasses in osteoblastic cells suggests biological involvement of bone related growth factors, peptides and cytokines in bone-bioactive glass bonding.

Search for quark-lepton compositeness and a heavy W' Boson using the enu channel in p p macro collisions at square root of [s] = 1.8 TeV

We present searches for quark-lepton compositeness and a heavy W' boson at high electron-neutrino transverse mass. We use approximately 110 pb(-1) of data collected in p p macro collisions at square root of [s] = 1.8 TeV by the CDF Collaboration during 1992-1995. The data are consistent with standard model expectations. Limits are set on the quark-lepton compositeness scale Lambda, the ratio of partial cross sections sigma(W'-->enu)/sigma(W-->enu), and the mass of a W' boson with standard model couplings. We exclude Lambda<2.81 TeV and a W' boson with mass below 754 GeV/c(2) at the 95% confidence level. Combining with our previously published limit obtained using the muon channel, we exclude a W' boson with mass below 786 GeV/c(2) at the 95% confidence level.

The phosphoinositide-dependent kinase, PDK-1, phosphorylates conventional protein kinase C isozymes by a mechanism that is independent of phosphoinositide 3-kinase

Phosphorylation by the phosphoinositide-dependent kinase, PDK-1, is required for the activation of diverse members of the AGC family of protein kinases, including the protein kinase C (PKC) isozymes. Here we explore the subcellular location of the PDK-1-mediated phosphorylation of conventional PKCs, and we address whether this phosphorylation is regulated by phosphoinositide 3-kinase. Pulse-chase experiments reveal that newly synthesized endogenous PKC alpha is primarily phosphorylated in the membrane fraction of COS-7 cells, where it is processed to a species that is phosphorylated at the activation loop and at two carboxyl-terminal positions. This "mature" species is then released into the cytosol. Deletion of the plekstrin homology domain of PDK-1 results in a 4-fold increase in the rate of processing of PKC indicating an autoinhibitory role for this domain. Autoinhibition by the plekstrin homology domain is not relieved by binding 3'-phosphoinositides; PKC is phosphorylated at a similar rate in serum-treated cells and serum-starved cells treated with the phosphoinositide 3-kinase inhibitors, LY294002 and wortmannin. Under the same conditions, the PDK-1-catalyzed phosphorylation of another substrate, Akt/protein kinase B, is abolished by these inhibitors. Our data are consistent with a model in which PDK-1 phosphorylates newly synthesized PKC by a mechanism that is independent of 3'-phosphoinositides.

Charged-particle multiplicity pp collisions at square root of (s) = 1.8 TeV

We report on a measurement of the mean charged-particle multiplicity of jets in dijet events with dijet masses in the range 80-630 GeV/c(2), produced at the Tevatron in pp collisions with square root (s) = 1.8 TeV and recorded by the Collider Detector at Fermilab. The data are fit to perturbative-QCD calculations carried out in the framework of the modified leading log approximation and the hypothesis of local parton-hadron duality. The fit yields values for two parameters in that framework: the ratio of parton multiplicities in gluon and quark jets, r identical withN(g-jet)(partons)/N(q-jet)(partons) = 1.7+/-0.3, and the ratio of the number of charged hadrons to the number of partons in a jet, K(charged)(LPHD) identical with N(charged)(hadrons)/N(partons) = 0.57+/-0.11.

[Study on healing art among the aboriginals of Taiwan]

The aboriginals of Taiwan who settled the island prior to the Han nationally can be divided into two groups, sinified plain people and less sinified mountain dwellers. The mountain dwellers fall into different groups; the Atayal, Saisiat, Bunun, Tsou, Rukai, Paiwan, Puyuma, Ami, and Yami. Before modern medicine penetrated the lives of the aboriginal, disease was treated by sorcery or by empirically applied herbal medicines. We visited various townships in Taiwan, including Chenggong, Daren, Haiduan, Puyuma, Changbin, and Yanping of Taidong County, Taidong City, and the offshore island of Lanyu; Mudan, Pindong County; and Fuxing, Taoyiuan County. We thereby covered the Ami, Paiwan,, Bunun, Puyuma, Yami, and Atayal groups. Although the aboriginals of Taiwan belong to the Malayo-Poly-nesian cultural system, there are nevertheless major differences among them. The aboriginals of Taiwan believe disease to be a punishment of the gods or the malicious interference of evil spirits. The various groups have distinct shamanistic rituals. This paper discusses the practices of sorcery in the Paiway, bunun, and describes the herbal remedies used by them.

[Medicine in Taiwan, during the period of Dutch occupation]

During the 38 years of Dutch occupation, by dispatching doctors from the East Indie Company to Taiwan, working at the trading institution for clinical purpose, the Dutchman achieved its missionary and ruling aims. This paper analyses the causes of the Dutch not being able to root on Taiwan. Comparison is made on the medicines between the periods of Dutch occupation and the period of Japanese closed-door policy.

[Medicine in Taiwan during the period of Japanese occupation]

During this period, malaria, pneumonia, dysentery and enteritis, and acute infectious diseases, including plague, typhoid fever, dysentery, cholera, smallpox, infectious epidemic meningitis, malaria, tsutsugamushi and endemic diseases such as goitre were the important causes of death. In parasitology, the most important discovery was lung fluke, followed by research achievement in clinical and basic sciences. In Taiwan, studies on poisonous snake were proceeded rather early. The special medical system in this period included the Gynecological Hospital and medical insurance system. In the medical staff, not a few Japanese were included. Dr. Du Congming, who made great contributions to medicine in Taiwan, may be viewed as the father of medicine in Taiwan. A Journal of Taiwan Medical Association was published in Taiwan by the said Association.

[Medicine in Taiwan during the period of Japanese occupation]

During the period of 1894-1945, hygienic administration institutions were established in the central and local levels, responsible for general hygienic affairs, including prevention of infectious diseases, public health, anti-opium smoking and drug inspection. Medical education and research unit were also set up, such as Taibei Hospital, Taiwan Viceroy Medical School and Taibei Imperial University. From these institutions, not a few medical professionals were cultivated.

Effect of molecular weight of thermoreversible polymer on in vivo retention of rhBMP-2

To investigate the effect of polymer molecular weight (MW) on rhBMP-2 delivery by thermoreversible polymers, four polymers with similar lower critical solution temperatures (20 degrees -22 degrees C) but different MWs were studied. Thermoreversible polymers were based on N-isopropylacrylamide (NiPAM), ethyl methacrylate (EMA), and N-acryloxysuccinimide (NASI), and had MWs of either approximately 49 kDa or approximately 400 kDa. The NASI content was either 0 or 1-1.6%. High MW polymers, irrespective of their NASI content, formed a stable gel with significantly lower water uptake and exhibited a dense micelle with average pore size smaller than the low MW polymers. NiPAM/EMA polymers without NASI did not conjugate with recombinant human bone morphogenetic protein-2 (rhBMP-2). NiPAM/EMA polymers containing NASI, however, gave conjugation with rhBMP-2. For polymers without NASI, a high MW was essential for rhBMP-2 retention when injected intramuscularly in Sprague-Dawley rats. For NASI-containing polymers, the MW of the polymer did not make a significant difference because rhBMP-2 retention was equivalent for different size polymers. We conclude that polymer MW affects rhBMP-2 retention in vivo in polymers designed for physical entrapment of rhBMP-2, but not in polymers designed for chemical conjugation with rhBMP-2.

Double diffraction dissociation at the Fermilab Tevatron collider

We present results from a measurement of double diffraction dissociation in pp collisions at the Fermilab Tevatron collider. The production cross section for events with a central pseudorapidity gap of width Deltaeta(0)>3 (overlapping eta = 0) is found to be 4.43+/-0.02(stat)+/-1.18(syst) mb [ 3.42+/-0.01(stat)+/-1.09(syst) mb] at square root of (s) = 1800[630] GeV. Our results are compared with previous measurements and with predictions based on Regge theory and factorization.

Measurement of d sigma/dM and forward-backward charge asymmetry for high-mass Drell-Yan e(+)e(-) pairs from pp macro collisions at square root of s = 1.8 TeV

We report on a measurement of the mass dependence of the forward-backward charge asymmetry, A(FB), and production cross section d sigma/dM for e(+)e(-) pairs with mass M(ee)>40 GeV/c(2). The data sample consists of 108 pb(-1) of pp macro collisions at square root of s = 1.8 TeV taken by the Collider Detector at Fermilab during 1992-1995. The measured asymmetry and d sigma/dM are compared with the predictions of the standard model and a model with an extra Z' gauge boson.

Measurement of the top quark p(T) distribution

We have measured the p(T) distribution of top quarks that are pair produced in pp collisions at sqrt[s] = 1.8 TeV using a sample of tt decays in which we observe a single high- p(T) charged lepton, a neutrino, and four or more jets. We use a likelihood technique that corrects for the experimental bias introduced due to event reconstruction and detector resolution effects. The observed distribution is consistent with the standard model prediction. We use these data to place limits on the production of high- p(T) top quarks suggested in some models of anomalous top quark pair production.

RBP1L1, a retinoblastoma-binding protein-related gene encoding an antigenic epitope abundantly expressed in human carcinomas and normal testis

BACKGROUND

Antibodies isolated from cancer patients have been used to identify genes encoding tumor-associated antigen epitopes relevant to immune responses in cancer patients. In this report, we used an immunoglobulin G (IgG) purified from serum of a patient with breast cancer to identify its corresponding epitope, gene, and protein-retinoblastoma-binding protein-1-like protein-1 (RBP1L1)-and determined whether it is a potential molecular marker for various cancers.

METHODS

IgG purified from the serum of a patient with breast cancer was used to screen an MCF-7 breast cancer cell complementary DNA (cDNA) expression library for immunoreactive clones. The cDNAs identified were cloned and sequenced. Immunoreactivity of specific amino acids in the epitope was determined by western blot analysis and enzyme-linked immunosorbent assay. The cellular location of the antigen was determined by immunoperoxidase staining with purified RBP1L1-specific IgG. Gene expression in various human carcinomas and normal tissues was examined by northern blot analysis and the reverse transcription-polymerase chain reaction.

RESULTS

Our purified IgG recognized just one epitope on RBP1L1. The complete 5802-base-pair RBP1L1 cDNA encodes a 1226-amino acid protein containing the antigenic epitope IKPSLGSKK. The derived protein sequence of RBP1L1 shares 74% and 37% amino acid identity, respectively, with a partial sequence of the retinoblastoma-binding protein and the complete sequence of retinoblastoma-binding protein-1. The RBP1L1 epitope was localized to the cytoplasm of MCF-7 cells but was not detected in peripheral blood mononuclear cells. High expression of RBP1L1 messenger RNA was found in human breast, lung, colon, pancreatic, and ovarian cancers and in normal testis, but expression was limited in other normal tissues.

CONCLUSIONS

RBP1L1 appears to be a molecular marker associated with a broad range of human malignancies.

Engineering temperature-sensitive poly(N-isopropylacrylamide) polymers as carriers of therapeutic proteins

This study was carried out to engineer N-isopropylacrylamide (NiPAM) polymers that contain protein-reactive N-acryloxysuccinimide (NASI) and hydrophobic alkylmethacrylates (AMAs). These thermoreversible, protein-conjugating polymers hold potential for retention of therapeutic proteins at an application site where tissue regeneration is desired. The lower critical solution temperatures (LCST) of the polymers were effectively controlled by the AMA mole content. The AMAs with longer side-chains were more effective in lowering the LCST. Polymers without NASI exhibited a stable LCST in phosphate buffer and in serum over a 10-day study period. The LCST of polymers containing NASI was found to increase over time in phosphate buffer, but not in serum-containing medium. The LCST increase in phosphate buffer was proportional to the AMA content. The feasibility of localizing a therapeutic protein, recombinant human bone morphogenetic protein-2 (rhBMP-2), to a site of application was explored in a rat intramuscular injection model. The results indicated that polymers capable of conjugating to rhBMP-2 were most effective in localizing the protein irrespective of the LCST (13-25 degrees C). For polymers with no NASI groups, a lower LCST resulted in a better rhBMP-2 localization. We conclude that thermosensitive polymers can be engineered for delivery of therapeutic proteins to improve their therapeutic efficacy.

C-terminal fragments of the alpha 1C (CaV1.2) subunit associate with and regulate L-type calcium channels containing C-terminal-truncated alpha 1C subunits

L-type Ca(2+) channels in native tissues have been found to contain a pore-forming alpha(1) subunit that is often truncated at the C terminus. However, the C terminus contains many important domains that regulate channel function. To test the hypothesis that C-terminal fragments may associate with and regulate C-terminal-truncated alpha(1C) (Ca(V)1.2) subunits, we performed electrophysiological and biochemical experiments. In tsA201 cells expressing either wild type or C-terminal-truncated alpha(1C) subunits in combination with a beta(2a) subunit, truncation of the alpha(1C) subunit by as little as 147 amino acids led to a 10-15-fold increase in currents compared with those obtained from control, full-length alpha(1C) subunits. Dialysis of cells expressing the truncated alpha(1C) subunits with C-terminal fragments applied through the patch pipette reconstituted the inhibition of the channels seen with full-length alpha(1C) subunits. In addition, C-terminal deletion mutants containing a tethered C terminus also exhibited the C-terminal-induced inhibition. Immunoprecipitation assays demonstrated the association of the C-terminal fragments with truncated alpha(1C) subunits. In addition, glutathione S-transferase pull-down assays demonstrated that the C-terminal inhibitory fragment could associate with at least two domains within the C terminus. The results support the hypothesis the C- terminal fragments of the alpha(1C) subunit can associate with C-terminal-truncated alpha(1C) subunits and inhibit the currents through L-type Ca(2+) channels.

[The study of Fagopyrum tataricum complex prescription on type II diabetes rats]

OBJECTIVE

To observe the effect of Fagopyrum tatarium complex prescription on insulin resistance and indexes of blood stasis such as TG, TCh in type II diabetes rats.

METHOD

To obtain type II diabetes rat model, rats were injected 25 mg/kg STZ and fed on high energy feed.

RESULTS

Fagopyrum tataricum complex prescription (FTCP) was close or super to glyburide on relieving symptoms, preventing obesity, decreasing blood glucose level, improving insulin-sensitivity and blood stasis symptoms. FTCP could also prevent chronic complication of diabetes. No toxicity or side effect of FTCP was found.

A cell number-counting factor regulates group size in Dictyostelium by differentially modulating cAMP-induced cAMP and cGMP pulse sizes

A secreted counting factor (CF), regulates the size of Dictyostelium discoideum fruiting bodies in part by regulating cell-cell adhesion. Aggregation and the expression of adhesion molecules are mediated by relayed pulses of cAMP. Cells also respond to cAMP with a short cGMP pulse. We find that CF slowly down-regulates the cAMP-induced cGMP pulse by inhibiting guanylyl cyclase activity. A 1-min exposure of cells to purified CF increases the cAMP-induced cAMP pulse. CF does not affect the cAMP receptor or its interaction with its associated G proteins or the translocation of the cytosolic regulator of adenylyl cyclase to the membrane in response to cAMP. Pulsing streaming wild-type cells with a high concentration of cAMP results in the formation of small groups, whereas reducing cAMP pulse size with exogenous cAMP phosphodiesterase during stream formation causes cells to form large groups. Altering the extracellular cAMP pulse size does not phenocopy the effects of CF on the cAMP-induced cGMP pulse size or cell-cell adhesion, indicating that CF does not regulate cGMP pulses and adhesion via CF's effects on cAMP pulses. The results suggest that regulating cell-cell adhesion, the cGMP pulse size, or the cAMP pulse size can control group size and that CF regulates all three of these independently.

Search for neutral supersymmetric Higgs bosons in pp collisions at sqrt[s] = 1.8TeV

We present the results of a search for neutral Higgs bosons produced in association with b quarks in pp-->bb(phi)-->bbb final states with 91+/-7 pb(-1) of pp collisions at sqrt[s] = 1.8 TeV recorded by the Collider Detector at Fermilab. We find no evidence of such a signal and the data are interpreted in the context of the neutral Higgs sector of the minimal supersymmetric extension of the standard model. With basic parameter choices for the supersymmetric scale and the stop-quark mixing, we derive 95% C.L. lower mass limits for neutral Higgs bosons for tan(beta) values in excess of 35.

Delivery systems for BMPs: factors contributing to protein retention at an application site

BACKGROUND

Recombinant human bone morphogenetic proteins (rhBMPs) are being tested in clinical studies for their capacity to elicit bone formation. Biomaterials used in delivery systems also play a critical role in supporting the osteoinductive activity of BMPs, attributable to the controlled presentation of the BMPs to target cells. Despite extensive preclinical studies, the factors contributing to local rhBMP pharmacokinetics remain to be elucidated.

METHODS

The rhBMP pharmacokinetics were studied in a rat subcutaneous implant and in an intramuscular injection model. In situ levels of rhBMPs were quantitated with use of 125I-labeled tracers. The effects of protein structural features and the nature of the biomaterial implant were explored. Osteoinduction by biomaterial+rhBMP combinations was assessed by a semiquantitative, histology-based bone score.

RESULTS

With the use of rhBMP-2, rhBMP-4, and an N-truncated rhBMP-2, the protein isoelectric point was found critical for the initial retention of rhBMPs in an implant. Osteoinduction studies carried out in parallel indicated that rhBMPs with a higher implant retention elicited more bone formation. In the clinically used collagen+rhBMP-2 device, collagen crosslinking and sterilization were most influential in rhBMP-2 retention. To increase retention at an application site, thermoreversible polymers were engineered and shown to enhance local rhBMP-2 retention, especially by injectable delivery.

CONCLUSIONS

Two critical components of an osteoinductive device--namely, the biomaterial and the rhBMP--were shown to influence local protein pharmacokinetics and osteoinductive activity of the device. Designer biomaterials can provide an additional mechanism to modulate local protein pharmacokinetics.

CLINICAL RELEVANCE

These studies form the foundation of next-generation osteoinductive devices with improved potency at sites of desired bone regeneration and reduced side effects at other sites.

Production of chi(c1) and chi(c2) in pp collisions at sqrt[S] = 1.8 TeV

We have measured the ratio of prompt production rates of the charmonium states chi(c1) and chi(c2) in 110 pb(-1) of pp collisions at sqrt[s] = 1.8 TeV. The photon from their decay into J/psi(gamma) is reconstructed through conversion into e+e- pairs. The energy resolution this technique provides makes the resolution of the two states possible. We find the ratio of production cross sections sigma(chi(c2))/sigma(chi(c1)) = 0.96+/-0.27(stat)+/-0.11(syst) for events with pT(J/psi) > 4.0 GeV/c, /eta(J/psi)/ < 0.6, and pT(gamma) > 1.0 GeV/c.

[Effect of iodine intake on thyroid diseases and intelligence among schoolchildren in rural areas]

OBJECTIVE

To understand the throid function and intelligence among the schoolchildren in three rural areas with different iodine intakes in China to probe the side-effect of excessive iodine intake on intelligence of schoolchildren.

METHODS

Chinese version of Raven's test was made among rural schoolchildren, 190 from Panshan County, Liaoning Province, a low iodine intake area with the median urinary iodine (MUI) of 99 microgram/L among its inhabitants, 236 from Zhangwu County, Liaoning Province, a moderate iodine intake area with the MUI of 338 microgram/L, and 313 from Huanghua County, Hebei Province, an excessive iodine intake area with the MUI of 631 microgram/L. Thyroid function, thyroid autoantibody (TAA), and MUI were determined among 116, 110 and 112 from the above-mentioned schoolchildren from these three areas respectively.

RESULTS

There was no significant difference among the prevalence rates of overt hyperthyroidism, subclinical hyperthyroidism and overt hypothyroidism in the areas of Panshan, Zhangwu and Huanghua. However, a significant difference was found among the prevalence rates of subclinical hypothyroidism in theses three areas (P = 0.001). The prevalence rates of subclinical hypothyroidism in Huanghua and Zhangwu were 4.76 and 3.37 times higher than that in Panshan (P = 0.001). TAA was negative among all of the schoolchildren with subclinical hypothyroidism except for one. No significant difference was found among the positive rates of thyroid peroxidase antibody (TPOAb) and thyroglobulin antibody (TGAb) in these three areas. Serum thyroglobulin (TG) values in Huanghua were markedly higher than those in the other two areas (P = 0.015 7). Serum TG value in Zhangwu was higher than that in Panshan but with no significant difference. The IQ value of the schoolchildren in Huanghua was markedly higher than that in Zhangwu (P = 0.001 2). The IQ value of the schoolchildren in Panshan was lower than that in Huanghua and higher than that in Zhangwu but with no significant difference.

CONCLUSION

The increase of iodine intake may increase the risk of subclinical hypothyroidism among schoolchildren. In the area with excessive iodine intake, most of the subclicical hypothyroidism cases among schoolchildren are not of autoimmune origin. No obvious effect of excessive iodine intaue is found on mental development of schoolchildren.

First measurement of the ratio B(t --> Wb)/B(t --> Wq) and associated limit on the Cabibbo-Kobayashi-Maskawa element /V(tb)/

We present the first measurement of the ratio of branching fractions R identical withB(t-->Wb)/B(t-->Wq) from p_p collisions at sqrt[s] = 1.8 TeV. The data set corresponds to 109 pb(-1) of data recorded by the Collider Detector at Fermilab during the 1992-95 Tevatron run. We measure R = 0.94(+0.31)(-0.24)(stat+syst) or R>0.61 (0.56) at 90% (95)% C.L., in agreement with the standard model predictions. This measurement yields a limit on the Cabibbo-Kobayashi-Maskawa quark mixing matrix element /V(tb)/ under the assumption of three generations and unitarity.

The carboxyl terminus of protein kinase c provides a switch to regulate its interaction with the phosphoinositide-dependent kinase, PDK-1

The function of protein kinase C family members depends on two tightly coupled phosphorylation mechanisms: phosphorylation of the activation loop by the phosphoinositide-dependent kinase, PDK-1, followed by autophosphorylation at two positions in the COOH terminus, the turn motif, and the hydrophobic motif. Here we address the molecular mechanisms underlying the regulation of protein kinase C betaII by PDK-1. Co-immunoprecipitation studies reveal that PDK-1 associates preferentially with its substrate, unphosphorylated protein kinase C, by a direct mechanism. The exposed COOH terminus of protein kinase C provides the primary interaction site for PDK-1, with co-expression of constructs of the carboxyl terminus effectively disrupting the interaction in vivo. Disruption of this interaction promotes the autophosphorylation of protein kinase C, suggesting that the binding of PDK-1 to the carboxyl terminus protects it from autophosphorylation. Studies with constructs of the COOH terminus reveal that the intrinsic affinity of PDK-1 for phosphorylated COOH terminus is over an order of magnitude greater than that for unphosphorylated COOH terminus, contrasting with the finding that PDK-1 does not bind phosphorylated protein kinase C effectively. However, effective binding of the phosphorylated species can be induced by the activated conformation of protein kinase C. This suggests that the carboxyl terminus becomes masked following autophosphorylation, a process that can be reversed by the conformational changes accompanying activation. Our data suggest a model in which PDK-1 provides two points of regulation of protein kinase C: 1) phosphorylation of the activation loop, which is regulated by the intrinsic activity of PDK-1, and 2) phosphorylation of the carboxyl terminus, which is regulated by the release of PDK-1 to allow autophosphorylation.

Ultraviolet damage on natural gray hair and its photoprotection

The physicochemical properties of natural gray hair obtained from the heads of individuals and as well as commercial samples were investigated. No statistically significant differences were observed in terms of their central maximum diameter, central cross-sectional area, central ellipticity, average tensile strength, and average extent of transverse swelling between gray and black hair. The correlation between the elongation and the contraction of the cross-sectional area of hair fibers during extension was established as a statistically linear function, with a coefficient of 0.758. The damage on natural gray hair from ultraviolet (UV) irradiation were assessed by measuring the following parameters: hair color, Young's modulus, stress-to-break, wet combing force, dynamic advancing contact angle, tryptophan damage, cuticle abrasion, and transverse swelling of hair fiber in 0.1 N NaOH solution. It has been found that gray hair undergoes more severe UV damage and needs more UV protection than dark brown hair. Experimental results indicate that the quaternized UV absorber, cinnamidopropyltrimonium chloride (CATC), delivered from a simple shampoo system, is more substantive on hair and more effective in protecting hair from UV damage than a conventional UV filter. CATC also provided an additional conditioning benefit on hair.

HBV-specific peptide associated with heat-shock protein gp96

Glycoprotein 96 (gp96), a member of the heat-shock protein family, can elicit priming of antigen-specfic cytotoxic T lymphocytes, when bound to antigenic viral or tumour peptides. We used direct peptide isolation from purified gp96 and microsequencing to show that a virus-specific peptide is bound to gp96 derived from liver tissues of patients with hepatitis B virus (HBV)-induced hepatocellular carcinoma. This virus-specific peptide has potential for engineering tumour vaccines against hepatocellular carcinoma and chronic HBV infection.

Association of L-type calcium channels with a vacuolar H(+)-ATPase G2 subunit

The class C L-type calcium (Ca(2+)) channels have been implicated in many important physiological processes. Here, we have identified a mouse vacuolar H(+)-ATPase (V-ATPase) G2 subunit protein that bound to the C-terminal domain of the pore-forming alpha(1C) subunit using a yeast two-hybrid screen. Protein-protein interaction between the V-ATPase G subunit and the alpha(1C) subunit was confirmed using in vitro GST pull-down assays and coimmunoprecipitation from intact cells. Moreover, treatment of cells expressing L-type Ca(2+) channels with a specific inhibitor of the V-ATPase blocked proper targeting of the channels to the plasma membrane.

Bone affinity of a bisphosphonate-conjugated protein in vivo

Growth factors capable of stimulating bone formation are potential therapeutic agents for osteoporosis treatment. It is essential, however, that a targeting mechanism is incorporated into the growth factors to deposit them at osseous tissue with minimal distribution to extraskeletal sites. To this end, a strategy has been developed in which a bone-seeking molecule, 1-amino-1,1-diphosphonate methane (aminoBP), was chemically conjugated to a model protein, bovine serum albumin (BSA). This study was carried out to assess the bone affinity of the conjugates in a tibia injection model. Using ovariectomized (OVX) rats, initial (3 h) retention of BSA and aminoBP-BSA were found to be equivalent when injected into the medullary cavity of tibia. After 1 day, an 8- and 12-fold higher tibiae retention of the protein was obtained in normal and OVX rats as a result of aminoBP conjugation. A similar result ( approximately 12-fold difference) was also obtained in OVX rats after 3 days. We concluded that aminoBP conjugation to BSA imparted a high bone affinity and enhanced bone retention of proteins in normal and OVX rats.

Measurement of J/psi and psi(2S) polarization in pp collisions at sqrt[s] = 1.8 TeV

We have measured the polarization of J/psi and psi(2S) mesons produced in pp collisions at sqrt[s] = 1.8 TeV, using data collected at the Collider Detector at Fermilab during 1992-1995. The polarization of promptly produced J/psi [psi(2S)] mesons is isolated from those produced in B-hadron decay, and measured over the kinematic range 4 [5.5]<P(T)<20 GeV/c and |y|<0.6. For P(T) greater than or approximately equal 12 GeV/c we do not observe significant polarization in the prompt component.

Role of the C terminus of the alpha 1C (CaV1.2) subunit in membrane targeting of cardiac L-type calcium channels

We have previously demonstrated that formation of a complex between L-type calcium (Ca(2+)) channel alpha(1C) (Ca(V)1.2) and beta subunits was necessary to target the channels to the plasma membrane when expressed in tsA201 cells. In the present study, we identified a region in the C terminus of the alpha(1C) subunit that was required for membrane targeting. Using a series of C-terminal deletion mutants of the alpha(1C) subunit, a domain consisting of amino acid residues 1623-1666 ("targeting domain") in the C terminus of the alpha(1C) subunit has been identified to be important for correct targeting of L-type Ca(2+) channel complexes to the plasma membrane. Although cells expressing the wild-type alpha(1C) and beta(2a) subunits exhibited punctate clusters of channel complexes along the plasma membrane with little intracellular staining, co-expression of deletion mutants of the alpha(1C) subunit that lack the targeting domain with the beta(2a) subunit resulted in an intracellular localization of the channels. In addition, three other regions in the C terminus of the alpha(1C) subunit that were downstream of residues 1623-1666 were found to contribute to membrane targeting of the L-type channels. Deletion of these domains in the alpha(1C) subunit resulted in a reduction of plasma membrane-localized channels, and a concomitant increase in channels localized intracellularly. Taken together, these results have demonstrated that a targeting domain in the C terminus of the alpha(1C) subunit was required for proper plasma membrane localization of the L-type Ca(2+) channels.

Search for scalar top and scalar bottom quarks in pp collisions at square root s=1.8 TeV

We have searched for direct pair production of scalar top and scalar bottom quarks in 88 pb-1 of pp collisions at sqrt[s]=1.8 TeV with the CDF detector. We looked for events with a pair of heavy flavor jets and missing energy, consistent with scalar top (bottom) quark decays to a charm (bottom) quark and a neutralino. The numbers of events that pass our selections show no significant deviation from standard model expectations. We compare our results to the next-to-leading order scalar quark production cross sections to exclude regions in scalar quark-neutralino mass parameter space.

[Risk factors for nosocomial infections after total knee replacement]

OBJECTIVE

To investigate prevalence and risk factors of nosocomial infections in patients with total knee replacement.

METHODS

From August 1993 to October 1998, total knee replacement was performed on 363 patients (503 knees). The difference of nosocomial infection rates was statistically analyzed in comparison with different age, primary disease, and associated disease groups.

RESULTS

No statistically significant difference was observed in nosocomial infection when compared rheumatoid arthritis with osteoarthritis, bilateral total knee replacement (TKR) with unilateral TKR and different ages. However, the higher nosocomial infection rate was related to the following factors: revision surgery, steroid administration and diabetes urinary infection. 28 female patients demonstrated higher urinary infection rate than that in other systems.

CONCLUSIONS

Nosocomial infection rate of TKR in rheumatoid cases is related to steroid administration, accompanying diabetes mellitus, previous knee surgery, aged women and retention of urinary catheter. It is feasible to prevent nosocomial infection by controlling the above-mentioned risk factors.

Proteolytic processing of the C terminus of the alpha(1C) subunit of L-type calcium channels and the role of a proline-rich domain in membrane tethering of proteolytic fragments

Although most L-type calcium channel alpha(1C) subunits isolated from heart or brain are approximately 190-kDa proteins that lack approximately 50 kDa of the C terminus, the C-terminal domain is present in intact cells. To test the hypothesis that the C terminus is processed but remains functionally associated with the channels, expressed, full-length alpha(1C) subunits were cleaved in vitro by chymotrypsin to generate a 190-kDa C-terminal truncated protein and C-terminal fragments of 30-56 kDa. These hydrophilic C-terminal fragments remained membrane-associated. A C-terminal proline-rich domain (PRD) was identified as the mediator of membrane association. The alpha(1C) PRD bound to SH3 domains in Src, Lyn, Hck, and the channel beta(2) subunit. Mutant alpha(1C) subunits lacking either approximately 50 kDa of the C terminus or the PRD produced increased barium currents through the channels, demonstrating that these domains participate in the previously described (Wei, X., Neely, a., Lacerda, A. E. Olcese, r., Stefani, E., Perez-Reyes, E., and Birnbaumer, L. (1994) J. Biol. Chem. 269, 1635-1640) inhibition of channel function by the C terminus.

Bisphosphonate conjugation to proteins as a means to impart bone affinity

Growth factors are endogenous proteins capable of stimulating new bone formation, but their clinical benefit for systemic stimulation of bone mass has not been demonstrated. The critical challenge is to deliver a significant dose of the proteins to bone after intravenous injection. This challenge may be overcome by derivatizing proteins with ligands that exhibit a high bone affinity (e.g., bisphosphonates). To demonstrate the feasibility of this approach, 1-amino-1,1-diphosphonate methane (aminoBP) was conjugated to a model protein, albumin. The conjugation was performed by (1) converting the amino group of aminoBP to a thiol group using 2-iminothiolane, (2) derivatizing the albumin amino groups with a thiol-reactive sulfosuccinimidyl-4-(N-maleimidomethyl)-1-cyclohexane carboxylate, and (3) reacting the derivatized albumin with thiolated aminoBP. Typically, 1-4 aminoBP molecules per albumin were obtained. The conjugated albumin exhibited a high affinity to hydroxyapatite that was proportional to the extent of conjugation. The conjugates were shown to exhibit a high affinity to bone matrix in vitro in a serum-containing medium. Once bound to bone matrix, the conjugates were found to desorb more slowly than the unmodified albumin, especially from bone whose organic matrix was removed by ashing. In conclusion, conjugation of bisphosphonates to albumin was shown to impart a high bone affinity to the protein, and such conjugates can be potentially targeted to bone.