bluuebunny/crossref_metadata_2025_split huggingface dataset:
Antisense modulation of the coding or regulatory sequence of the folate receptor (folate binding protein‐1) in mouse embryos leads to neural tube defects
Authors: Hansen Deborah K. , Streck Randal D. , Antony Asok C. 
Published: July 2003

AbstractBACKGROUNDAlthough folic acid decreases the incidence of neural tube defects (NTDs) in humans, the mechanism for this protection is unknown. We have employed antisense technology to alter expression of the gene for the folate receptor (folate binding protein‐1 [Folbp1]) in mouse embryos cultured in vitro.METHODSEmbryos were explanted on day 8 of gestation and cultured for 44 hr. Several oligodeoxyribonucleotides designed to modulate the coding region or a regulatory sequence in the 5′‐untranslated region of Folbp1 were microinjected into the amniotic sac of embryos at the beginning of the culture period.RESULTSTwo different antisense sequences to the 5′ and 3′ coding region in Folbp1 produced concentration‐dependent increases in the number of embryos with NTDs. Coinjection of 5‐methyltetrahydrofolate with these sequences decreased the frequency of abnormal embryos. A semi‐quantitative RT‐PCR technique used to measure the amount of Folbp1 mRNA in treated and control embryos confirmed that the mRNA level was decreased by treatment with the antisense sequences. An antisense oligodeoxyribonucleotide to a 17 base cis regulatory element also generated a concentration‐dependent increase in the frequency of embryos with NTDs, and a decrease in the level of Folbp1 mRNA.CONCLUSIONSThese results demonstrate that alterations in expression of Folbp1 by perturbing either the coding sequence or a critical regulatory cis‐element can play a role in NTDs. Birth Defects Research (Part A) 67475–487, 2003. © 2003 Wiley‐Liss, Inc.
Development of fluridil, a topical suppressor of the androgen receptor in androgenetic alopecia
Authors: Seligson Allen L , Campion Brian K , Brown Jason W , Terry Ron C , Kucerova Renata , Bienova Martina , Hajduch Marian , Sovak Milos 
Published: July 2003

AbstractNonsteroidal antiandrogens (AA) cannot be topically used for androgenetic alopecia (AGA) because of systemic resorption. A new class of androgen receptor (AR) suppressors designed for safe topical treatment of AGA was synthesized from (3‐amino‐2‐hydroxy‐2‐methyl‐N‐(4‐nitro‐3‐trifluoromethyl)phenyl) propanamide (BP‐34), to contain perfluoroalkyl moieties. The trifluoromethyl derivative (fluridil) at 10 μM decreased expression of the AR in LNCaP human cells by 95%, its serum half‐life was 6 h; it decomposes hydrolytically to BP‐34 and trifluoroacetic acid. Acute intraperitoneal maximum tolerated dose (MTD) of fluridil in mice is 270–300 mg/kg/d and the subacute MTD is 450 mg/kg/d. The oral LD50 in mice was 2,872 mg/kg in males, 2,232 mg/kg in females, and >2,500 mg/kg in rats. Fluridil solution in isopropanol was not cutaneously absorbed in rabbits, did not sensitize or show any phototoxic or photoallergic effects on guinea pig skin, and demonstrated no skin irritation potential in rabbits and humans. Fluridil solid induced only slight and reversible eye irritancy in rabbits and displayed no cytotoxicity to rabbit corneal fibroblasts in vitro. Fluridil demonstrated no significant mutagenicity potential by Ames method. In a double‐blind study, 43 males with AGA, Norwood grade II to Va, used topical 2% fluridil in isopropanol or the vehicle daily for 12 months. Anagens (growing hairs) increased in the fluridil group from 76% to 89%. All hematological and biochemistry values remained within normal range, including testosterone, which varied but seasonally. No fluridil or its decomposition product (BP‐34) was detected in serum. No adverse side effects were reported. Drug Dev. Res. 59:292–306, 2003. © 2003 Wiley‐Liss, Inc.
Optimization of drug release from dermatological semisolid preparations
Authors: Eros István , Abu‐Eida Ehab Youseff , Csóka Ildikó , Sánta Zsuzsa , Cserne Annamária , Kövér Tünde 
Published: July 2003

AbstractThe aim of the present study was to optimize the process of drug release. Factors which influence drug release were studied in detail and their effects were described numerically. The factors studied were as follows: the concentration of the pharmacon (salicylic acid); its particle size; its suspended, dissolved, solubilized, or molecular encapsulated state;, the composition of the vehicle; the quantities of the polar and apolar components; and the viscosity of the vehicle. Drug release studies were carried out with Hanson's vertical diffusion cell. The process was described quantitatively by the slope of the equation describing the time‐course of the liberation, by the quantity of pharmacon liberated in 8 h and also by the optimization parameter determined on the basis of the 22 model of the factorial design method. Increase of the concentration of salicylic acid was found to be accompanied by an exponential rise in drug release, while the extent of liberation decreased linearly with increasing viscosity. The greatest increase in the optimization parameter was observed when the polarity of the vehicle was changed. The process of liberation consists of the following steps: dissolution of the pharmacon, diffusion of the dissolved molecules, and their distribution. The current data revealed that the distribution is the most important element and exerts the greatest influence on optimal drug release. Drug Dev. Res. 59:316–325, 2003. © 2003 Wiley‐Liss, Inc.
Ventricular PKC‐ϵ and humoral signaling in DOCA‐Salt rats treated with labedipinedilol‐A
Authors: Yeh Jwu‐Lai , Liang Jyh‐Chong , Liou Shwu‐Fen , Lin Young‐Tso , Sheu Sheng‐Hsiung , Lai Wen‐Ter , Shin Shyi‐Jang , Chen Ing‐Jun 
Published: July 2003

AbstractEffects of oral antihypertensive monotherapy with labedipinedilol‐A, labetalol, atenolol, amlodipine, prazosin (20 mg kg−1 day−1), and short‐acting nifedipine (3 mg kg−1 day−1) on DOCA‐salt‐induced translocation of ventricular protein kinase C‐ϵ(PKC‐ϵ), humoral signaling, and the cardiovascular system were investigated in rats for 4 weeks. The triple blocking activities of labedipinedilol‐A (α/β‐adrenoceptor blockade and calcium entry blockade) were compared with single blocking activities of selective drugs. Cytosolic PKC‐ϵ immunoreactivity was decreased by labedipinedilol‐A, short‐acting nifedipine, amlodipine, prazosin, labetalol, atenolol, and losartan. Membranous PKC‐ϵ immunoreactivity was significantly decreased by labedipinedilol‐A, amlodipine, prazosin, labetalol, and atenolol. Labedipinedilol‐A and prazosin more potently decreased membranous than cytosolic PKC‐ϵ expression. Labedipinedilol‐A, labetalol, and atenolol effectively inhibited DOCA‐salt‐induced increases in angiotensin II (Ang II). All antihypertensive agents reduced endothelin‐1 (ET‐1) levels in urine and cardiac weight growth. Treatments with labedipinedilol‐A, labetalol, atenolol, and amlodipine normalized DOCA‐salt‐induced ANP increases. Prazosin did not decrease ANP. Short‐acting nifedipine elevated ANP. During long‐term antihypertensive therapy in DOCA‐salt hypertensive rats, single blockade drugs did not fully inhibit ventricular PKC‐ϵ translocation or Ang II, ET‐1, and ANP humoral signaling. However, triple blockade labedipinedilol‐A therapy had a wide range of α/β‐adrenergic receptor and calcium channel inhibitory activities, including diminished reflux tachycardia, inhibition of PKC‐ϵ translocation, and reduction of Ang II, ET‐1, and ANP formation. Drug Dev. Res. 59:307–315, 2003. 2003 Wiley‐Liss, Inc.
Subacute toxicity of all‐trans‐retinoic acid loaded biodegradable microspheres in rats
Authors: Choi Yongdoo , Lee Chulkyu , Park Kyeongsoon , Kim Sang Yoon , Kim Sun Hee , Han Shin , Kim Sung Hyun , Byun Youngro 
Published: July 2003

AbstractBiodegradable microspheres containing all‐trans‐retinoic acid (atRA) were prepared previously to enhance the clinical efficacy of atRA for chemoprevention. In this study, subacute toxicity of atRA in sustained release was evaluated after subcutaneous administration of 0, 25, 50, and 100 mg atRA/kg of atRA‐loaded microspheres. After the subcutaneous injection of atRA‐loaded microspheres, the atRA concentration in plasma was maintained in the range of 3.5–25 ng/ml for 2–3 weeks. When 100 mg atRA/kg was administered, the atRA concentration in plasma was maintained at levels greater than 10 ng/ml and severe toxic effects were observed. When the dose of 50 mg atRA/kg was administered, the plasma concentration of atRA was maintained below 10 ng/ml over 3 weeks and only mild signs of toxicity were observed. Therefore, it was concluded that the dosage of atRA‐loaded microspheres should be less than 50 mg atRA/kg for chemopreventive applications against carcinogenesis. Considering recovery from intoxication, the optimum interval for repeated injection of the microspheres was suggested to be over 4 weeks. In addition, it was found that the atRA concentration in plasma should be controlled below 10 ng/ml to minimize toxic effects of atRA. Drug Dev. Res. 59:326–332, 2003. © 2003 Wiley‐Liss, Inc.
TNF‐α  mediates the induction of nitric oxide synthase in macrophages but not in neutrophils in experimental cutaneous leishmaniasis
Authors: Fonseca Simone G. , Romão Pedro R. T. , Figueiredo Florêncio , Morais Ruth H. , Lima Hermênio C. , Ferreira Sérgio H. , Cunha Fernando Q. 
Published: July 2003

AbstractLeishmania major infection in C57BL/6 mice is controlled by the activation of a Th1 response and nitric oxide (NO) production by macrophages. TNF‐α is considered one of the most important cytokines involved in this response. In the present study, we investigated the expression of nitric oxide synthase (iNOS) in the inflammatory cells present in the lesion and draining lymph nodes, and the cytokine production by lymph node cells in animals treated with anti‐TNF‐α. Our results demonstrated that mice treated with anti‐TNF‐α presented an increase in the number of parasites and the size of lesion, but they were able to control the infection. The increase in the lesion size correlated to the reduction of iNOS activity in the draining lymph nodes. Furthermore, the anti‐TNF‐α treatment also reduced the expression of iNOS in the macrophages, but did not affect the iNOS expression in the neutrophils. The anti‐TNF‐α mAb did not reduce the iNOS expression in IFN‐γ‐stimulated L. major infected neutrophils in vitro. Anti‐TNF‐α mAb treatment caused an increase in the production of IFN‐γ and IL‐10 by the lymph node cells from infected mice. Consequently, these results suggest that neutrophils do not respond to anti‐TNF‐α treatment and might be a source of NO to control L. major infection under these experimental conditions.
Possible involvement of glial cell line‐derived neurotrophic factor and its receptor, GFRα1, in survival and maturation of thymocytes
Authors: Kondo Sachiko , Kishi Hiroyuki , Tokimitsu Yoshiharu , Muraguchi Atsushi 
Published: July 2003

AbstractThe glial cell line‐derived neurotrophic factor (GDNF) and its receptors (GFR) play important roles in the promotion of survival and differentiation of central and peripheral neuronal populations. We show that GFRα1, a component of GDNF receptor, was expressed in thymocytes at an early stage of thymocyte‐development and was involved in the survival of thymocyte precursors. GFRα1and GDNF were expressed in thymus, but not in spleen or lymph nodes in adult mice. During embryonic thymocyte development, GFRα1 was predominantly expressed on thymocytes from days 14.5 to 16.5 of gestation, and thereafter its expression gradually declined. In adult thymus, GFRα1 was expressed only on CD4–CD8– double‐negative (DN) thymocytes, but not on CD4+CD8+ double‐positive or single‐positive thymocytes. It was strongly expressed on RAG2–/– thymocytes arrested at the DN stage, and ist expression was reduced during their differentiation after in vivo anti‐CD3 antibody stimulation. Additionally, fetal thymocyte precursors grew in serum‐free medium of the fetal thymus organ culture system in the presence of recombinant GDNF (rGDNF), while the cells without rGDNF died. These results suggested that GDNF/GFRα1 are involved in the survival of both the nervous system and DN immature thymocytes.
N‐terminal destruction signals lead to rapid degradation of the major histocompatibility complex class II transactivator CIITA
Authors: Schnappauf Felix , Hake Sandra B. , Carvajal Margarita M. Camacho , Bontron Séverine , Lisowska‐Grospierre Barbara , Steimle Viktor 
Published: July 2003

AbstractMajor histocompatibility complex (MHC) class II molecules play an essential role for the cellular immune response by presenting peptide antigens to CD4+ T cells. MHC class II molecules and genes show a highly complex expression pattern, which is orchestrated through a master regulatory factor, called CIITA (class II transactivator). CIITA controls MHC class II expression not only qualitatively, but also quantitatively, and has therefore a direct influence on the CD4 T cell‐dependent immune response. CIITA is itself tightly regulated not only on the transcriptional level, but as we show here also on the protein level. CIITA is subjected to a very rapid protein turnover and shows a half‐life of about 30 min. Inhibition of degradation by proteasome inhibitors and the identification of ubiquitylated CIITA intermediates indicate that the degradation of CIITA is mediated by the ubiquitin‐proteasome system. We identified two regions mediating degradation within the N‐terminal domain of CIITA. N‐terminal fusions or deletions stabilized CIITA, indicating that the N termini contribute to degradation. Several non‐functional CIITA mutants are partially stabilized, but we provide evidence that transcriptional activity of CIITA is not directly linked to degradation.
Induction of arthritis by single monoclonal IgG anti‐collagen type II antibodies and enhancement of arthritis in mice lacking inhibitory FcγRIIB
Authors: Nandakumar Kutty Selva , Andrén Maria , Martinsson Pernilla , Bajtner Estelle , Hellström Silvia , Holmdahl Rikard , Kleinau Sandra 
Published: July 2003

AbstractIgG anti‐collagen type II (CII) antibodies (Ab) can induce arthritis in healthy mice. Here we have investigated if single monoclonal IgG anti‐CII Ab can induce arthritis in CIA‐susceptible DBA/1 mice and if there is an IgG subclass dependency. The involvement of Fc receptors for IgG (FcγR) in anti‐CII Ab‐mediated arthritis was also investigated by comparing the clinical outcome in DBA/1 mice to those in FcγR‐deficient mice. We demonstrate for the first time that single mAb to naive DBA/1 mice can induce persistent arthritis. Histology of the inflamed joints revealed massivecellular infiltrate and cartilage and bone destruction. All IgG subclasses tested (IgG1, IgG2a and IgG2b) were arthritogenic, with the IgG1 and IgG2b isotypes as the dominating arthritogenic Ab. Pathogenicity was dependent on engagement of activating FcγR, as FcRγ‐deficient mice were completely resistant to Ab‐mediated arthritis. The arthritis induced with the IgG1 and IgG2b Ab was also inhibited by FcγRIII disruption, whereas arthritis mediated by the IgG2a Ab was not substantially affected. The arthritic response of the IgG1 and IgG2b isotypes, but not of the IgG2a Ab, was further enhanced in mice lacking the inhibitory FcγRIIB. These results demonstrate that single IgG anti‐CII mAb can induce erosive arthritis and that IgG anti‐CII Ab mediate arthritis by engagement of FcγR.
Cyclic AMP increases endogenous granulocyte colony‐stimulating factor formation in monocytes and THP‐1 macrophages despite attenuated TNF‐α formation
Authors: Hareng Lars , Meergans Thomas , von Aulock Sonja , Volk Hans‐Dieter , Hartung Thomas 
Published: July 2003

AbstractThe cytokine granulocyte colony‐stimulating factor (G‐CSF) is in broad clinical use to treat neutropenia, and trials on its use in immunosuppressed conditions and infections are ongoing. To aply G‐CSF effectively, it is crucial to understand the regulation and distribution of its endogenous formation. Since G‐CSF release is mediated, at least in part, by TNF‐α formation, we investigated whether drugs suppressing TNF‐α also impair G‐CSF production. Surprisingly, G‐CSF formation was enhanced in lipopolysaccharide (LPS)‐stimulated blood from a pentoxifylline‐treated patient. In the presence of dibutyryl‐cAMP, forskolin, tolafentrine or 3‐isobutyl‐1‐methylxanthine, LPS‐induced G‐CSF formation was enhanced in THP‐1 cells, primary monocytes and whole blood. Correspondingly,rp‐8‐bromo‐cAMP suppressed LPS‐induced G‐CSF release. Addition of prostaglandin E2 enhanced and indomethacin suppressed G‐CSF formation. Reporter gene studies showed that dibutyryl‐cAMP enhanced LPS‐induced G‐CSF promoter activity, indicating a transcriptional up‐regulation. Furthermore, disruption of a newly identified putative cAMP‐responsive element (CRE) in the G‐CSF promoter demonstrated the regulatory role for G‐CSF gene transcription. In conclusion, endogenous G‐CSF formation critically depends on both TNF‐α and cyclooxygenase products, exerting effects via cAMP and the CREin the G‐CSF promoter. This might have bearing for drug side effects, putative G‐CSF mimetics and our understanding of G‐CSF immunobiology.
The effects of B7‐dependent costimulation on T cell division and survival in vivo and in vitro are dependent on antigen concentration
Authors: Lumsden Joanne M. , Prasad Simon J. , Peach Robert J. , Ronchese Franca 
Published: July 2003

AbstractWe used 5‐(and 6‐) carboxyfluorescein diacetate succinimidyl ester labeled TCR‐transgenic CD4+ T cells to investigate the contribution of B7 costimulation to T cell activationand clonal expansion. B7 costimulation was blocked with the fusion protein cytotoxic T lymphocyte‐associated antigen‐4 (CTLA‐4)‐Ig, which prevents the interaction of B7 with its receptor CD28 on T cells. CTLA4‐Ig had different effects depending on the density of antigen (Ag)/MHC ligands available by T cells. In the presence of CTLA4‐Ig, tenfold higher concentrations of Ag were required for T cells to undergo cell division in vitro. At high Ag concentrations, T cell division occurred at comparable rates whether in the presence or absence of CTLA4‐Ig; however, T cell survival and clonal expansion were strongly inhibited. Addition of IL‐2 restored T cell survival but not responsiveness to low doses of Ag. In vivo, B7 costimulation was similarly required for the survival of Ag‐specific T cells but not for cell division in response to high amounts of Ag. Thus, B7 costimulation regulates CD4+ T cell responses by promoting cell division in the presence of limiting amounts of Ag, and by protecting T cells from the onset of apoptosis.
Mechanism(s) promoting HIV‐1 infection of primary unstimulated T lymphocytes in autologous B cell/T cell co‐cultures
Authors: Döpper Susanne , Wilflingseder Doris , Prodinger Wolfgang M. , Stiegler Gabriele , Speth Cornelia , Dierich Manfred P. , Stoiber Heribert 
Published: July 2003

AbstractResting CD4+ T cells in the lymphoid tissue (LT) are essential producers of virions at the beginning of HIV infection in vivo. We previously developed a model that allowed in vitro infection of non‐prestimulated T lymphocytes in the presence of autologous B lymphocytes and complement. In this study, we try to clarify the mechanism(s) responsible for virus transmission in unstimulated autologous B cell/T cell co‐cultures. Ex vivo analyses of patient plasma samples revealed that HIV was opsonized. Flow cytometry showed that opsonized virus preferentially bound to complement receptor (CR)‐2 on B lymphocytes in primary B cell/T cell co‐cultures. As indicated by cytokine measurements and transwell experiments, soluble factors seemed to play a minor role in enabling infection. Rather, direct interaction between B and T lymphocytes and direct binding of opsonized virus to CR2 on B cells turned out to be essential for productive infection. Antibodies blocking cell‐cell adhesion inhibited p24 antigen production. An anti‐CR2 antibody blocking C3d‐CR2 binding also significantly reduced viral replication. Since the infection of unstimulated T cells by opsonized primary HIV isolates in the presence of B cells was highly efficient independent of the tropism of the virus, this mechanism may be critical in the pathogenesis of HIV.
A minimal human immunostimulatory CpG motif that potently induces IFN‐γ and IFN‐α production
Authors: Fearon Karen , Marshall Jason D. , Abbate Christi , Subramanian Sandhya , Yee Priscilla , Gregorio Josh , Teshima Glen , Ott Gary , Tuck Stephen , Van Nest Gary , Coffman Robert L. 
Published: July 2003

AbstractRecent reports have shown that immunostimulatory sequences (ISS) containing CpG motifs have minimal length requirements (≥12 bases) for the exertion of immune‐enhancing function upon mammalian cells. Herein we demonstrate that short ISS (5–7 bases), which exhibit no activity on their own, induce IFN‐γ and IFN‐α secretion from human peripheral blood mononuclear cells when adsorbed to the surface of cationic poly(D,L‐lactide‐co‐glycolide) microparticles (cPLGA). Utilizing this technique, we discovered a minimal ISS sequence for induction of IFN‐γ and IFN‐α from human cells: 5′‐TCGXX‐3′. These short ISS/cPLGA formulations targeted PDC in similar fashion to longer ISS ODN, the activity of which does not require (but is enhanced by) cPLGA. PDC stimulated with short ISS/cPLGA responded with enhanced uptake of ISS and elevated production of cytokines, including IFN‐α. However, ISS‐responsive B cells did not respond to short ISS/cPLGA, underlining the plasmacytoid dendritic cell selectivity of this formulation. These results describe a novel technique for formulating active, but very short, ISS oligodeoxynucleotide that allows for the dissection and characterization of minimal immunostimulatory CpG motifs.
Germ‐line transcription occurs on both the functional and the non‐functional alleles of immunoglobulin constant heavy chain genes
Authors: Delpy Laurent , Le Bert Marc , Cogné Michel , Khamlichi Ahmed Amine 
Published: July 2003

AbstractIn B cells undergoing class switching, recombination is usually directed to the same switch sequences on both homologous chromosomes and is generally preceded by germ‐line transcription initiated from I promoters upstream of immunoglobulin constant heavy chain genes. Whether germ‐line transcription occurs on both alleles or is restricted to the productive one has not been directly addressed before. To clearly distinguish between these two possibilities, a system is needed in which one might detect allele‐specific germ‐line transcripts. We used homologous recombination to set up twoin vivo systems in which one γ3 allele was marked by a loxP sequence whereas the other allele was silenced by inhibiting μ heavy chain production. Here, we provide evidence that germ‐line transcription occurs on both the functional and the non‐functional alleles.