A mitochondrial exopolyphosphatase activity modulated by phosphate demand in Rhipicephalus (Boophilus) microplus embryo

This study describes Exopolyphosphatases (PPX) activity in mitochondria of Rhipicephalus microplus embryos. Mitochondria were isolated by differential centrifugation and PPX activity was analyzed through the hydrolysis of the substrate Polyphosphate (Poly P(15)). We investigated the influence of NADH, NAD+, Pi and ADP in a concentration range of 0.1-2.0 mM. Poly P hydrolysis was stimulated about two-fold by NADH and strongly inhibited by Pi. The PPX activity also increased in the presence of the respiratory substrates pyruvic and succinic acids, and this stimulatory effect disappeared upon addition of KCN. Mitochondrial respiration was activated by ADP using poly P as the only source of Pi. Endogenous poly P content changed following PPX activity during embryogenesis from the first up to 18th day of development. The data describe exopoly P as being modulated by Pi demand and related to energy supply during embryogenesis of hard ticks.

Lipopolysaccharide inhalation exacerbates allergic airway inflammation by activating mast cells and promoting Th2 responses

BACKGROUND

Bacterial infection occasionally exacerbates asthma, although the cellular and molecular mechanisms have not been well defined. An involvement of mast cells has been suggested, as lipopolysaccharides (LPS)-induced cytokine production from mast cells in vitro.

OBJECTIVE

This study was undertaken to examine the effects of LPS inhalation on mast cell functions and allergen-specific immune responses in a murine model of asthma.

METHODS

Female BALB/c mice or mast cell-deficient W/W(v) mice were immunized intraperitoneally with ovalbumin (OVA). Mice were challenged with aerosolized OVA or OVA with LPS daily from day 21 to day 24. Twenty-four hours after the last challenge, airway inflammation and OVA-specific immune responses were examined. Allergen-specific T cell responses were further analysed by adoptively transferring OVA-specific CD4(+) T cells. Expression of chemokines in the lung was also examined.

RESULTS

LPS inhalation with OVA resulted in exacerbated airway infiltration, which was not evident in mast cell-deficient mice. IL-5 production by mast cells in the lung was enhanced by LPS inhalation. OVA-specific IgE production as well as proliferation, cytokine production and local infiltration of OVA specific T-helper lymphocytes type 2 (Th2) were also enhanced. Up-regulated expression of Th2- and/or eosinophil-attracting chemokines was observed in the lung of mice inhalated with LPS.

CONCLUSIONS

LPS inhalation exacerbates airway inflammation, which is accompanied by mast cell activation and enhanced Th2 responses. These observations provide clues towards understanding the mechanisms of bacterial infection-induced exacerbation of the clinical features of asthma.

Glucose metabolism during embryogenesis of the hard tick Boophilus microplus

Glucose metabolism plays an essential role in the physiology and development of almost all living organisms. In the present study we investigated glucose metabolism during the embryogenesis of the hard tick Boophilus microplus. An increase in glucose and glycogen content during the embryonic development of B. microplus was detected and shown to be due to the high enzyme activity of both gluconeogenesis and glycolytic pathways. Glucose 6-phosphate (G-6P), formed by hexokinase, is driven mainly to pentose-phosphate pathway, producing fundamental substrates for cellular biosynthesis. We detected an increase in glucose 6-phosphate dehydrogenase and pyruvate kinase activities after embryo cellularization. Accumulation of key metabolites such as glycogen and glucose was monitored and revealed that glycogen content decreases from day 1 up to day 6, as the early events of embryogenesis take place, and increases after the formation of embryo cellular blastoderm on day 6. Glucose and guanine (a sub-product of amino acids degradation in arachnids) accumulate almost concomitantly. The activity of phosphoenolpyruvate carboxykinase was increased after embryo cellularization. Taken together these data indicate that glycogen and glucose, formed during B. microplus embryogenesis after blastoderm formation, are produced by intense gluconeogenesis.

Cell death during preoviposition period in Boophilus microplus tick

Programmed cell death (PCD) is present during the development of multicellular organisms and occurs from embryogenesis to death. In females of Boophilus microplus, the mass of several organs is reduced after the detachment from the host. In order to better characterize the cell death process that eliminates unnecessary tissues, the degeneration of salivary glands, ovaries and synganglia was investigated using DNA fragmentation in agarose gel, comet and TUNEL assays, and apoptosis activation pathway by the caspase assay. DNA fragmentation and enzymatic activity of caspase-3 were observed in salivary glands and ovaries at 48 and 72h after tick removal from the host; in synganglia these parameters were maintained at low levels upon 48h. The results obtained suggest that there is a refined control of tissue maintenance through apoptosis.

Vaccination of bovines with recombinant Boophilus Yolk pro-Cathepsin

Boophilus Yolk pro-Cathepsin (BYC) is an aspartic proteinase found in Boophilus microplus eggs that is involved in the embryogenesis and has been tested as antigen to compose an anti-tick vaccine. The vaccine potential of a recombinant BYC expressed in Escherichia coli (rBYC) was investigated. rBYC was purified and used to immunize Hereford cattle. The sera of bovines immunized with rBYC recognized the native BYC with a titer ranging from 125 to 4000. Furthermore, immunized bovines challenged with 20,000 larvae presented an overall protection of 25.24%. The partial protection obtained against B. microplus infestation with the recombinant protein immunization was similar to the already described for native BYC immunization.

Boophilus microplus: Its saliva contains microphilin, a small thrombin inhibitor

Saliva of the cattle tick Boophilus microplus contains two thrombin inhibitors, BmAP and microphilin. This work presents the purification and characterization of microphilin. It was purified from the saliva by gel filtration, ultrafiltration through a 3 kDa cut-off membrane and affinity chromatography in a thrombin-Sepharose column. Analysis by mass spectrometry showed a molecular mass of 1770 Da. Microphilin is the smallest salivary thrombin inhibitor peptide known to date. It inhibits fibrinocoagulation and thrombin-induced platelet aggregation with an IC(50) of 5.5 microM, is temperature resistant and its inhibitory activity was abolished by protease K treatment. Microphilin did not inhibit the amidolytic activity of the enzyme upon a small chromogenic substrate, but inhibited the hydrolysis of a substrate that binds both catalytic site and exosite I. Therefore, we propose that microphilin blocks thrombin at exosite I.

Relationship between glutathione S-transferase, catalase, oxygen consumption, lipid peroxidation and oxidative stress in eggs and larvae of Boophilus microplus (Acarina: Ixodidae)

Glutathione S-transferases (GSTs) are enzymes that act in excretion of physiologic and xenobiotic substances, protecting cells against chemical toxicity and stress. In this work, we characterized the enzymatic activity of GST in eggs and larvae of cattle tick Boophilus microplus, on different days after oviposition and eclosion. The results showed that the GST activity varied depending on the time elapsed after oviposition and eclosion. Molecules involved in mechanism of protection from oxidative stress are correlated with the increase in GST activity. The oxygen consumption kinetics showed a positive correlation with the increase in GST activity during embryogenesis. A high content of thiobarbituric acid reactive substances were observed in egg and larva extracts, indicating that ticks face high oxidative stress during embryogenesis and aging. In eggs and larvae, GST activity can be correlated to kinetic parameters of oxidative stress such as catalase and glutathione. In addition, GST activity showed strong positive correlation with lipid peroxidation, an indication that it plays a role in oxidant defences in eggs.

Kinetics of energy source utilization in Boophilus microplus (Canestrini, 1887) (Acari: Ixodidae) embryonic development

The present work evaluates the kinetics of utilization of the main potential energy sources throughout the embryonic developmental stages of Boophilus microplus. The embryonic development of this arthropod is completed in 21 days. Cellularization of the blastoderm occurs on the 6th day and is rapidly followed by germ band extension and segmentation, whose first signs are visible on the 7th day. Cellularization is typically a maternal-driven process, carried out by molecular determinants deposited in the oocyte during oogenesis. On the other hand, segmentation is of zygotic nature, being the consequence of the synthesis of various components by the growing embryo. The enhancement in total B. microplus RNA was observed after cellularization, corroborating the replacement of maternal-driven processes by embryonic zygotic expression. An abrupt increase in oxygen consumption was observed from cellularization until the 8th day of development. The reduction in dry weight at the same period and the susceptibility of oxygen consumption to KCN suggest that the respiration process is activated during early embryonic development. A marked decrease in total lipid content occurred between the 5th and 7th days of development, suggesting this is the main energy source for cellularization. A major reduction in carbohydrate content occurred later, between the 7th and 9th days, and it could be assigned to the morphological segmentation of the embryo. Although the total amount of proteins remains unchanged from oviposition to hatching, a 15% reduction in vitellin (VT) content was observed before cellularization, up to the 4th day after egglaying. This observation was correlated to the synthesis of new proteins needed to support early embryo development. Additional 20% of VT was consumed thereafter, mainly at the end of embryogenesis, and in this case VT is probably used as energy source to the older embryo. Altogether, these data indicate different energy sources for maternal and zygotic driven processes.

NK026680, a novel compound suppressive of dendritic cell function, ameliorates mortality in acute lethal graft-versus-host reaction in mice

A role for dendritic cells (DCs) has been emphasized in the onset of acute graft-versus-host disease (GVHD). We have made efforts to develop a new strategy for suppression of DC functions with a chemical compound in the treatment of acute GVHD. We here describe the immunological characterization of the new chemical compound NK026680. It was found that NK026680 significantly suppressed (1) expression of CD83, CD86, and major histocompatibility complex (MHC) class I and II antigens on human monocyte-derived DCs, (2) excretion of interleukin-12p40 on activation of monocyte-derived DCs, (3) allogeneic responses of human and mouse T cells and (4) mortality in mice with acute GVHD evoked across MHC class I or II. The beneficial effect of NK026680 administered orally was without any recognizable adverse effects. Early intervention in acute GVHD was required for this effect, indicating that an early event in acute GVHD is a critical target of NK026680. We propose the use of NK026680 as a prophylactic for acute GVHD.

Purification and antigenicity of two recombinant forms of Boophilus microplus yolk pro-cathepsin expressed in inclusion bodies

The tick Boophilus microplus is a bovine ectoparasite present in tropical and subtropical areas of the world and the use of vaccines is a promising method for tick control. BYC is an aspartic proteinase found in eggs that is involved in the embryogenesis of B. microplus and was proposed as an important antigen in the development of an anti-tick vaccine. The cDNA of BYC was amplified by PCR and cloned for expression in two forms with and without thioredoxin fusion protein (Trx), coding recombinant proteins named rBYC-Trx and rBYC, respectively. Expression, solubility, and yields of the two forms were analyzed. The recombinant proteins were expressed in inclusion bodies (IBs) and three denaturant agents (N-lauroyl sarcosine, guanidine hydrochloride, and urea) were tested for IBs solubilization. The N-lauroyl sarcosine solubilized 90.4 and 92.4% of rBYC-Trx and rBYC IBs, respectively, and was the most efficient denaturant. Two recombinant forms were affinity-purified by Ni2+-Sepharose under denaturing conditions. After dialysis, the yield of soluble protein was 84.1% for r-BYC-Trx and 5.9% for rBYC. These proteins were immune-reactive against sera from rabbit, mouse, and bovine previously immunized with native BYC, which confirms the antigenicity of the recombinant BYCs expressed in the Escherichia coli system.

Altered regulation of c-jun and its involvement in anchorage-independent growth of human lung cancers

The c-jun oncogene is frequently overexpressed in non-small-cell lung cancers (NSCLC), but its functional involvement in lung cancer development has not been clearly elucidated. In this study, we found that among the immediate-early serum responsible genes, exemplified by c-jun, c-fos and c-myc, induction of c-jun in a human bronchial epithelial cell line, BEAS-2B, was dependent on anchorage, in contrast to clear induction of c-fos and c-myc under both anchorage-dependent and -independent conditions. In fact, forced expression of c-jun in BEAS-2B cells significantly increased cell viability and colony formation in soft agar. Furthermore, we also found that such anchorage-dependent regulation of c-jun was lost in a significant fraction of human lung cancer cell lines. Interestingly, suppressed anchorage-independent but not anchorage-dependent growth was noted by constitutive expression of a dominant-negative c-jun mutant in a lung cancer cell line showing dysregulated and sustained c-jun expression in the absence of anchorage. These findings suggest that dysregulated c-jun expression may be involved in the acquisition of anchorage independence in the process of human lung carcinogenesis.

Biomechanical Rationale of Endoscopic Decompression for Lumbar Spondylolysis as an Effective Minimally Invasive Procedure - A Study Based on the Finite Element Analysis

We evaluated the biomechanical behavior of the endoscopic decompression for lumbar spondylolysis using the finite element technique. An experimentally validated, 3-dimensional, non-linear finite element model of the intact L3 - 5 segment was modified to create the L4 bilateral spondylolysis and left-sided endoscopic decompression. The model of Gill's laminectomy (conventional decompression surgery of the spondylolysis) was also created. The stress distributions in the disc and endplate regions were analyzed in response to 400 N compression and 10.6 Nm moment in clinically relevant modes. The results were compared among three models. During the flexion motion, the pressure in the L4/5 nucleus pulposus was 0.09, 0.09 and 0.16 (MPa) for spondylolysis, endoscopic decompression and Gill's procedure, respectively. The corresponding stresses in the annulus fibrosus were 0.65, 0.65 and 1.25 (MPa), respectively. The stress at the adjoining endplates showed an about 2-fold increase in the Gill's procedure compared to the other two models. The stress values for the endoscopic and spondylolysis models were of similar magnitudes. In the other motions, i. e., extension, lateral bending, or axial rotation, the results were similar among all of the models. These results indicate that the Gill's procedure may lead to an increase in intradiscal pressure (IDP) and other biomechanical parameters after the surgery during flexion, whereas the endoscopic decompression did not change the segment mechanics after the surgery, as compared to the spondylolysis alone case. In conclusion, endoscopic decompression of the spondylolysis, as a minimally invasive surgery, does not alert mechanical stability by itself.

Molecular cloning and sequence analysis of cDNAs encoding for Boophilus microplus, Haemaphysalis longicornis and Rhipicephalus appendiculatus actins

The nucleotide and deduced amino acid sequences of the actins from ticks, Boophilus microplus, Haemaphysalis longicornis and Rhipicephalus appendiculatus, have been determined. Nucleotide sequence analysis showed open reading frames of 1128-nucleotide-long encoding proteins of 376 amino acids with a predicted molecular weight of 41.82 kDa each. Comparison between the nucleic acid and deduced amino acid sequences as well as structural and phylogenetic analyses of these genes confirmed the high similarity among actins from ticks in comparison to other species.

Proteolytic activity of Boophilus microplus Yolk pro-Cathepsin D (BYC) is coincident with cortical acidification during embryogenesis

In a previous report (Parasitology 116 (1998) 525) we isolated and characterized Boophilus Yolk pro-Cathepsin (BYC), an aspartic proteinase precursor from the eggs of the hard tick. The present study was designed to characterize the function of BYC in the consumption of vitellin (VT), the major yolk protein, during embryogenesis. Both purified BYC and total egg homogenate proteolytic activity showed a similar pH dependence profile with an acidic optimum. Purified BYC presented higher activity against VT as a substrate when compared to other proteins. The VT degradation pattern observed in vitro also showed a similar profile to that observed in vivo. Co-localization of BYC and acidic cortical yolk granules was performed by immunocytochemistry and confocal microscopy. Proton-pumping activity of yolk granules in vitro was higher in eggs collected 4 day after oviposition than in newly laid eggs. Taken together, our data suggest that BYC plays a major role in the degradation of VT and that its activity is controlled by acidification of yolk platelets localized at the cortical cytoplasm of the developing Boophilus microplus egg.

Lytic infection of Epstein-Barr virus (EBV) in hemophagocytic syndrome associated with EBV-induced lymphoproliferative disorder

This report describes lytic infection with Epstein-Barr virus (EBV) in three cases of hemophagocytic syndrome (HPS) presumably associated with EBV-induced lymphoproliferative disorder. All cases were previously healthy females with ages ranging from 52 to 87 years who showed a fulminant clinical course with accompanying fever, liver dysfunction, and disseminated intravascular coagulation. Cases 1 and 2 showed proliferation of atypical T lymphocytes, and case 3 showed proliferation of atypical B lymphocytes. Hemophagocytic histiocytes were observed in the bone marrow, lymph nodes, spleen, and liver. Atypical lymphocytes in all cases showed a positive reaction for both EBV-encoded small RNA (EBER) indicating latent infection with EBV and immediate early mRNAs of the Bam HI fragment of lower stranded frame (BHLF), indicating lytic infection by in situ hybridization. Interestingly, BHLF-positive cells were predominant in all cases. It is possible that reactivation of EBV infection may be involved in triggering the induction of cytokines and abnormal activation of histiocytes.

Effect of acaricides on the activity of a Boophilus microplus glutathione S-transferase

In the present study, we report the effect of several acaricides on the enzyme activity of a Boophilus microplus recombinant glutathione S-transferase (rGST). GST was expressed in Escherichia coli and was purified with glutathione (GSH) affinity column chromatography. The kinetic constants were determined by reacting GST with the substrates 1-chloro-2,4-dinitrobenzene (CDNB) and glutathione. We report the effect of several acaricides on the enzyme activity of rGST. Some acaricides (ethion, amitraz, chlorpyrifos, DDT, cypermethrin, diazinon, ivermectin, deltamethrin and flumethrin) inhibited rGST. Contrarily, coumaphos had an activating effect. Although the accurate mechanisms of the B. microplus resistance to acaricides remain elusive, this work helps in understanding how acaricides can interact with GST.

Quantitative imaging of protein-protein interactions by multiphoton fluorescence lifetime imaging microscopy using a streak camera

Fluorescence lifetime imaging microscopy (FLIM) using multiphoton excitation techniques is now finding an important place in quantitative imaging of protein-protein interactions and intracellular physiology. Recent developments in multiphoton FLIM methods are reviewed and a novel multiphoton FLIM system using a streak camera is described. An example of a typical application of the system is provided in which the fluorescence resonance energy transfer between a donor-acceptor pair of fluorescent proteins within a cellular specimen is measured.

A Boophilus microplus vitellin-degrading cysteine endopeptidase

Here we describe the purification and characterization of a vitellin (VT) degrading cysteine endopeptidase (VTDCE) from eggs of the hard tick Boophilus microplus. A homogeneous enzyme preparation was obtained by chromatographic fractionation on ion-exchange and gel filtration columns and an autolysis step. This step consisted of incubation of a semipurified enzyme (after the first ion-exchange chromatography) at pH 4.0 that dissociated the enzyme from VT, to which VTDCE is naturally tightly associated. The enzyme purity was confirmed by capillary and native gel electrophoresis, and SDS-PAGE suggested the enzyme is a dimer of 17 and 22 kDa. VTDCE was active upon several synthetic substrates, with a preference for a hydrophobic or a basic residue in P1, and a hydrophobic residue in P2. VTDCE also hydrolysed haemoglobin, albumin, gelatin and vitellin. VTDCE is inactive in the absence of DTT and was totally inhibited by E-64, indicating it is a cysteine endopeptidase. Our results suggest that VTDCE is a major enzyme involved in yolk processing during B. microplus embryogenesis.

Binding and storage of heme by vitellin from the cattle tick, Boophilus microplus

We have previously shown (, Curr. Biol. 9, 703-706) that the cattle tick Boophilus microplus does not synthesize heme, relying solely on the recovery of the heme from the diet to make all its hemeproteins. Here we present evidence that Vitellin (VN(1)), the main tick yolk protein, is a reservoir of heme for embryo development. VN was isolated from eggs at different days throughout embryogenesis. Immediately after oviposition, Boophilus VN contains approximately one mol of heme/mol of protein. During embryo development about one third of egg VN is degraded. The remaining VN molecules bind part of the heme released. These results suggest that VN functions as a heme reservoir, binding any free heme that exceeds the amount needed for development. In vitro measurement of the binding of heme to VN showed that each VN molecule binds up to 31 heme molecules. The association of heme with VN strongly inhibits heme-induced lipid peroxidation, suggesting that binding of heme is an important antioxidant mechanism to protect embryo cells from oxidative damage. This mechanism allows this hematophagous arthropod to safely store heme obtained from a blood meal inside their eggs for future use. Taken together our data suggest that, besides its known roles, VN also plays additional functions as a heme deposit and an antioxidant protective molecule.

cDNA cloning, expression and characterization of a Boophilus microplus paramyosin

The tick Boophilus microplus is a 1-host tick that causes important losses to bovine herds, and protective antigens are being investigated in order to develop vaccines that avoid the use of acaricides. Paramyosins are multi-functional invertebrate muscle proteins, whose roles may include host immunomodulation, and seem to be a prominent candidate in a schistosomiasis vaccine. We report here the cloning, expression and characterization of a B. microplus paramyosin (BmPRM). Sequence analysis of the full length coding sequence cDNA shows high identity to other arthropod paramyosin sequences, and the predicted molecular weight, pI and secondary structure are consistent with a typical paramyosin. Western-blot expression analysis indicates the presence of BmPRM in all tissues and developmental stages tested, but not in saliva. The recombinant protein (rBmPRM) was shown to bind both IgG and collagen. Possible implications of these activities with host evasion mechanisms are discussed.

Expression and immunolocalization of a Boophilus microplus cathepsin L-like enzyme

Efforts are being undertaken to control tick infestations that cause important economic losses. A cathepsin L-like endopeptidase of Boophilus microplus was expressed in Escherichia coli; the recombinant enzyme was capable of hydrolysing gelatin, tick vitellin and bovine haemoglobin. In this paper we focus on the expression and local of synthesis of this enzyme in the tick. RT-PCR experiments showed that this endopeptidase is transcribed in the gut of partially engorged tick females. In immunoblotting, polyclonal antibodies against the recombinant enzyme reacted with proteins of larvae older than 5 days, of fully and partially engorged female gut. In immunolocalization experiments the enzyme was localized in probable secretory cells of the gut. Based on our findings we postulate that BmCL1 may be involved in haemoglobin degradation in the B. microplus gut. This enzyme may be used as target for the control of this parasite.

Cloning and partial characterization of a Boophilus microplus (Acari: Ixodidae) glutathione S-transferase

A cDNA of glutathione S-transferase (GST) was isolated from a cDNA library of salivary glands of Boophilus microplus. The recombinant protein was purified by glutathione affinity chromatography and assayed upon the chromogenic substrate CDNB. The 864 bp cloned fragment was sequenced and showed an open reading frame coding for a protein of 220 amino acids. Expression of the GST gene was tested by RT-PCR in tick tissues and larvae mRNA. Comparison of the deduced amino acid sequence with GSTs from other species revealed that the enzyme is closely related to the mammalian class mu GSTs.

Argyrophilic nucleolar organizer regions as a prognostic indicator of laryngeal carcinomas

Nucleolar organizer regions (NORs) were studied in surgically removed specimens from 76 patients with squamous cell carcinomas of the larynx using an argyrophilic (Ag) staining technique. The mean number of AgNORs per nucleus was 4.3 +/- 1.38 (SD). The mean AgNOR number for T1 or T2 disease was statistically lower than that for T3 or T4 lesions (P < 0.05). The mean AgNOR number was lower in patients with N0 disease than in patients with N1 or N2 or N3 tumors (P < 0.05). There was also a statistically significant difference between the mean AgNOR number for stage II and stage III disease (P < 0.01), for stage III and stage IV disease (P < 0.05), but not for stage I and stage II disease. According to the histological grading, there was a significant difference between the mean AgNOR number for the well-differentiated and moderately differentiated tumors (P < 0.05), and for the moderately differentiated and poorly differentiated types (P < 0.01). These results suggest that the number of AgNORs in the nucleus is a significant indicator of laryngeal carcinomas.

Preliminary findings of chromosomal alterations and expression of cell cycle genes in head an neck tumors

The genesis and progression of malignant tumors may be related to certain somatic mutations and the accumulation of multiple chromosomal alterations. Using four freshly resected malignant tumors, we investigated the relationship between chromosomal alteration and expression of cell cycle regulatory genes. Specimens of thyroid hyperplasia and normal thyroid tissue were also investigated. As cell cycle regulating genes, we chose the cdc2 gene that encodes the p34cdc2 protein kinase, a major kinase of the cell cycle, and the RCC1 gene that is essential for coupling between S and M phases. Three of the malignant tumors contained cells with chromosomal alterations, including one polyploid and two aneuploid. The DNA content of cells in thyroid hyperplasia was the same as in the normal gland. The amount of p34cdc2 protein was very low in cells of both normal thyroid and hyperplastic tissue, and grew very slowly as compared with malignant tumors. There was no significant relationship between the amount of RCC1 and ploidy pattern.

Cloning and partial characterization of a Boophilus microplus (Acari: Ixodidae) calreticulin

We report the cloning, sequence characterization and expression analysis of a calreticulin (CRT) coding cDNA of Boophilus microplus. CRT is a calcium-binding protein involved in multiple cell functions and possibly implicated in parasites host immune system evasion. The CRT cDNA sequence and its molecular characterization are described. Sequence similarity and phylogenetic analyses indicate a close relationship to other arthropod CRT sequences. The CRT cDNA was also expressed in a procariotic system and the recombinant protein (rBmCRT) was used to raise antibodies in a rabbit. Expression analyses of the corresponding gene in different developmental stages and tissues were performed by RT-PCR and Western-blot, which indicated a ubiquitous expression of the B. microplus calreticulin gene and demonstrated its presence in saliva. Sera of tick-infested bovines suggested that this protein may not be able to induce an IgG-based humoral response in its natural host.

Seroprevalence and molecular evidence for the presence of bovine immunodeficiency virus in Brazilian cattle

Data on the worldwide distribution of bovine immunodeficiency virus (BIV) and bovine leukemia virus (BLV) is limited. A prevalence study of antibodies to BIV and BLV was conducted in six different cattle herds in Brazil. Out of a total of 238 sera analyzed, 11.7% were found positive for anti-BIV p26 antibodies as determined by Western blot analysis, 2.1% were positive for anti-BLV gp51 antibodies as detected by immunodiffusion test. Peripheral blood mononuclear cells from BIV seropositive cattle were found to have BIV-provirus DNA, as detected by nested polymerase chain reaction. A nucleotide sequence corresponding to a 298 bp fragment of the BIV pol gene was also analyzed. Amino acid sequences of these Brazilian pol gene products showed 98.0 to 100% homology to the American strain BIV R29, 97.0 to 99.0% to Japanese BIV isolates, and divergence ranged from 0 to 4.0% among Brazilian BIV isolates. This evidence of the presence of BIV and BLV infections in Brazil should be considered a health risk to Brazilian cattle populations and a potential causative agent of chronic disease in cattle.

Novel distance dependence of diffusion constants in hyaluronan aqueous solution resulting from its characteristic nano-microstructure

Material transports in hyaluronan (HA) aqueous solution were investigated applying two different techniques, i.e., pulsed field gradient NMR (PFG-NMR) and photochemical quenching, to the measurement of diffusion constants to show a sharp contrast resulting from the difference of the spectroscopic observation time while the same probe molecules were commonly used in two experiments. The value from PFG-NMR reflects the relatively long transport along which the majority of the molecules are retarded by the mesh structure of HA solution. In such inhomogeneous fluids, the observable diffusion constant should generally depend on the observation time and, i.e., the averaged distance of diffusion. Quantitative discussion, which compares the obtained characteristic distance of diffusion with the pore size, clarifies the role of the nano-microstructure of HA solution forming small pores surrounded by the polymer chain networks.

Heterogeneous transforming growth factor (TGF)-beta unresponsiveness and loss of TGF-beta receptor type II expression caused by histone deacetylation in lung cancer cell lines

Transforming growth factor (TGF)-beta strongly inhibits epithelial cell proliferation. Alterations of TGF-beta signaling are thought to play a role in tumorigenesis. We show in the present study that most lung cancer cell lines have lost the growth-inhibitory response to TGF-beta signal, and that those with TGF-beta unresponsiveness can be divided into two major groups, TGF-beta type II receptor (TGFbetaRII)(+)/Smad7(+) and TGFbetaRII(-)/Smad7(-), suggesting the heterogeneous mechanisms underlying the TGF-beta responsiveness. The mechanism of the loss of TGFbetaRII expression of the latter group was further studied, identifying aberrant DNA methylation of the promoter region in a limited fraction of cell lines. Interestingly, we found that the alteration of chromatin structure because of histone deacetylation may also be involved, showing a good correlation with loss of TGFbetaRII expression. This notion was supported by the findings of a restriction enzyme accessibility assay, of a chromatin immunoprecipitation assay with anti-acetyl histone antibodies, and of an in vivo induction of TGFbetaRII expression by histone deacetylase inhibitors including trichostatin A (TSA) and sodium butyrate. In vitro induction of TGFbetaRII promoter reporter activity by TSA was also detected and found to require the CCAAT box within the -127/-75 region. A positive regulatory mechanism for TGFbetaRII expression in a TGF-beta-expressing cell line was also investigated, and a TPA-responsive element (TRE)-like motif, TRE2, was detected in addition to the previously reported TRE-like motif Y element in the positive regulatory region. Alterations in two discrete proteins interacting with these two TRE-like motifs were also suspected of being involved in the loss of TGFbetaRII expression. This is the first study to demonstrate that, in addition to the TSA-responsive region and TRE2 motif in the TGFbetaRII promoter, the alteration of histone deacetylation may be involved in the loss of TGFbetaRII expression in lung cancer cell lines.

Cognitive behavioral therapy and fasting therapy for a patient with chronic fatigue syndrome

Cognitive behavioral therapy temporarily alleviated symptoms of a chronic fatigue syndrome patient but the anxiety about rehabilitation into work became stronger and his symptoms worsened. This patient was successfully rehabilitated by fasting therapy. Natural killer cell activity and serum acylcarnitine levels recovered after fasting therapy. Though fasting therapy transiently increased physical and mental subjective symptoms, the patient gained self-confidence by overcoming difficulties after fasting therapy. A combination of cognitive behavioral therapy and fasting therapy is promising as a treatment for chronic fatigue syndrome.

Two new pyrrolidine alkaloids, radicamines A and B, as inhibitors of alpha-glucosidase from Lobelia chinensis Lour

Two new pyrrolidine alkaloids, radicamines A and B were isolated as inhibitors of alpha-glucosidase from Lobelia chinensis Lour. (Campanulaceae). Radicamines A and B were formulated as (2S,3S,4S,5S)-2-hydroxymethyl-3,4-dihydroxy-5-(3-hydroxy-4-methoxyphenyl)-pyrrolidine (1) and (2S,3S,4S,5S)-2-hydroxymethyl-3,4-dihydroxy-5-(4-hydroxyphenyl)-pyrrolidine (2) on the basis of spectroscopic analyses and chemical methods.

Persistent increase in chromosome instability in lung cancer: possible indirect involvement of p53 inactivation

Karyotype and fluorescence in situ hybridization analyses have demonstrated the frequent presence of an altered static state of the number of chromosomes (ie, aneuploidy) in lung cancer, but it has not been directly established whether aneuploidy is in fact associated with a persistent increase in the rate of chromosomal losses and gains (ie, chromosome instability, or CIN). The study presented here used a panel of 10 lung cancer cell lines to provide for the first time direct evidence that CIN is a common feature in lung cancer cell lines in association with the presence of significant aneuploidy. In addition, we found that the CIN phenotype correlates well with the presence of p53 mutations. However, human papilloma virus 16-E6-directed inactivation of p53 in a representative non-CIN lung cancer cell line did not result in the induction of CIN, at least up to the 25th generation, suggesting that inactivation of p53 itself is unlikely to directly induce CIN in lung cancer cells. Interestingly, however, significant CIN could be induced in conjunction with the generation of aneuploid populations when the mitotic spindle formation was transiently abrogated in p53-inactivated cells. These results suggest that inactivation of p53 may allow lung cancer cells to go through an inappropriate second division cycle under certain forms of mitotic stresses, which would result in the induction of the CIN phenotype in conjunction with the generation of aneuploidy.

Reduced expression and impaired kinase activity of a Chk2 mutant identified in human lung cancer

The checkpoint kinase Chk2 is phosphorylated and activated in response to DNA damage such as ionizing radiation. Recently, we found a somatic mutation of CHK2 with clear loss of the wild-type allele in human lung cancer. Here we show that the mutant Chk2 exhibits modestly reduced in vitro kinase activity compared with wild type, whereas it is normally phosphorylated and activated after ionizing radiation. Interestingly, this mutant Chk2 protein was found to be less stable than wild type and could be expressed in various cell types only at a significantly reduced (20%) level of wild type. These findings confirm that the DNA damage checkpoint pathway involving CHK2 is indeed inactivated in this fatal adult cancer and also suggest that reduced expression of Chk2 may also be an important inactivating mechanism, contributing to the development of lung cancer.

Hyperbaric oxygen for anorexia nervosa

Hyperbaric oxygen was given to a patient with anorexia nervosa who had developed postoperative ileus, resulting in not only improvement in ileus, but also enhancement of intestinal movement, inducing the feeling of hunger, and thereby increasing food ingestion. Hyperbaric oxygen may be effective as an initial treatment for anorectic patients showing severe bloating and resistance to food ingestion.

Interleukin-15 Prevents Mouse Mast Cell Apoptosis through STAT6-mediated Bcl-xL Expression

Interleukin (IL)-15 is a member of the cytokine family with T and natural killer (NK) cell growth-promoting activity. In mast cells, however, IL-15 uses a distinct receptor system different from that used in T and NK cells. We recently reported that IL-15 induces STAT6 activation and IL-4 production in a mouse mast cell line (MC/9) and bone marrow-derived mast cells. In the present study, we have demonstrated that IL-15 prevents MC/9 and bone marrow-derived mast cell apoptosis induced by factor withdrawal or anti-Fas antibody treatment. IL-15 increased mRNA and protein levels of an anti-apoptotic protein (Bcl-x(L)) in these cells, whereas bcl-2 mRNA remained unchanged. In addition, the transcriptional activity of the bcl-x(L) promoter was increased by IL-15 in MC/9 cells. In an electrophoretic mobility shift assay, IL-15 induced STAT6 binding to the STAT recognition site in the bcl-x(L) gene promoter. Furthermore, the expression of a dominant-negative form of STAT6 abrogated the effects of IL-15 on both bcl-x(L) mRNA up-regulation and prevention of apoptosis in mast cells. Altogether, our results suggest that IL-15 plays an important role in maintaining the number of mast cells through Bcl-x(L) expression mediated by STAT6.

Lack of positive interaction between CO2 and hypoxic stimulation for P(CO2)-VAS response slope in humans

To compare the effect of hypoxia on ventilatory responses and respiratory sensation to carbon dioxide, 29 young adults were examined using a modified Read's rebreathing method with four experimental conditions. We used varying gas mixtures and kept PET(O2) constant at >300, 100, 80 and 60 mmHg for each four rebreathing tests. Respiratory sensation was measured by visual analog scale (VAS). The slope of the CO2-ventilation response curve increased significantly with hypoxia, confirming a positive ventilatory interaction between hypoxia and hypercapnia. However, the slope of the CO2-VAS response curve remained unchanged. The V(E)-VAS relation slope tended to become depressed with advancing hypoxia, i.e. the magnitude of VAS elicited by a given ventilation decreased with hypoxia, signifying that dyspneic sensation was effectively mitigated during hypoxic hyperventilation. We suggest that this relief of dyspneic sensation might be due to the inhibitory respiratory effect from augmented pulmonary stretch receptor (PSR) activity.

Advanced bladder cancer in a young female: a case report

We present a rare case of advanced bladder cancer in a young female. A 27-year-old woman had the chief complaint of proteinuria. A clinical examination revealed a papillary, broad-based bladder tumor with a clinical stage of T3, N3, M0. Preoperatively, 3 courses of neoadjuvant chemotherapy with methotrexate, adriamycin, and cisplatin were performed, and proved to be effective. Radical cystectomy was done and the histopathologically it was diagnosis as Grade 2 transitional cell carcinoma, which did not show any p53 gene mutation. The patient's postoperative clinical course was uneventful, and she remained disease free for 27 months. Bladder carcinoma in patients under 30 years of age tends to have a early stage and a low grade. However, the above described 27-year-old female patient demonstrated the advanced stage bladder tumor. Therefore, it should be kept in mind to accurately evaluate young patients with transitional cell carcinoma of the bladder and not to rule out the possibility of advanced disease even though a patient is young.

Hearing restoration from deafness after resection of a large cerebellopontine angle meningioma--case report

A 61-year-old man presented with a large cerebellopontine angle meningioma manifesting as a 1-year history of deafness on the right side, in whom hearing was restored from the deaf state immediately after tumor resection. Neuroimaging demonstrated a large mass in the right cerebellopontine angle, originating at the region adjacent to the jugular foramen. Audiometry showed his hearing was off-scale (> 105 dB) on the right. The tumor was successfully removed through the retrosigmoid approach, and the integrity of the 7th and 8th cranial nerves was maintained. The patient regained hearing on the day after the operation, which continued to improve until near-normal. The 8th cranial nerve function may recover dramatically after removal of non-acoustic tumors, even if preoperative hearing loss is profound. To maximize the opportunity to regain hearing, approaches which devastate cochlear function should be avoided and more meticulous manipulation during tumor removal is needed.

Attachment of Malassezia pachydermatis to the ear dermal cells in canine otitis externa

To investigate the predominance of Malassezia pachydermatis (M. pachydermatis) as a causative agent of canine otitis externa, ear cerumen samples were observed for adhesion of M. pachydermatis to the cornified epithelial cells by light and electron microscopes. The yeasts appeared not to adhere to the cornified epithelial cells directly, but they seemed to exist in the proximity of the epithelial cells with an electron opaque halo-like space around them. Polysaccharide and lipid staining techniques were conducted to identify the substances existing in that space. Lipid substances, not saccharides, were observed around the yeasts and the cornified epithelial cells. These results suggested that in the canine ear canal malassezia yeast attachment to the cornified epithelial cells is mediated by lipids.

Multiphotoreceptor and multioscillator system in avian circadian organization

Photoperiodism and circadian rhythms have been studied intensively in birds because Aves are typical seasonal breeders and diurnal animals. Light is the most important environmental factor involved in entrainment of circadian rhythms and photoperiodism. The eyes and the extraocular photoreceptors, such as the pineal organ and hypothalamus, are reported to have an important function not only for photoreception but also for circadian organization in nonmammalian vertebrates, including birds. In this report, we review the roles of the eyes, pineal organ, and deep brain as the components of the multiphotoreceptor and multioscillator system in avian circadian organization.

Usefulness of HMG-CoA reductase inhibitor in Japanese hyperlipidemic women within seven years of menopause

OBJECTIVE

To assess the therapeutic value of treatment with an HMG-CoA reductase inhibitor in women with hypoestrogenic hyperlipidemia caused by menopause.

DESIGN

Fifty-six women with total cholesterol (TC) levels of 220 mg/dl or more who were within 7 years of menopause were randomly assigned to receive an HMG-CoA reductase inhibitor (pravastatin 10 mg/day; treated group, 26 patients) or no medical treatment (nontreated group, 30 patients) in this 6-month nonblinded prospective trial.

RESULTS

In the treated group, the mean (SD) TC levels decreased significantly from 254.5+/-22.3 mg/dl at baseline to 204.7+/-22.2 mg/dl (19.6%), and the mean low-density lipoprotein cholesterol (LDL-C) level decreased significantly from 146.7+/-30.5 to 104.3+/-22.5 mg/dl (28.9%); the mean arteriosclerotic index decreased significantly from 2.98 to 2.08 (30.2%). There were no significant changes in either triglyceride levels or high-density lipoprotein cholesterol (HDL-C) levels. In the nontreated group, there were no significant changes in the TC, HDL-C, LDL-C, or triglyceride levels; there was also no change in the arteriosclerotic index. After 6 months, the TC level, LDL-C level, and arteriosclerotic index were significantly lower in the treated group compared with the nontreated group (p<0.01).

CONCLUSIONS

The results indicate that the HMG-CoA reductase inhibitor lowered TC and LDL-C levels and was useful in the treatment of hypoestrogenic hyperlipidemia for periods of at least 6 months.

Surface conduction on insulating BaTiO3 crystal suggesting an intrinsic surface electron layer

We report conduction measurements on the clean, free surface of transparent insulating BaTiO3 single crystals in high vacuum. We find that the insulating BaTiO3 crystals exhibit surface conductance that is dependent on the spontaneous polarization, whereas no conduction perpendicular to the surface is observed. The surface conduction shows semimetallic temperature dependence and persists down to at least 100 K. The observations suggest a two-dimensional electron on a clean, free ferroelectric surface that may be regarded as a ferroelectric metal. The results have important implications for understandings of the fundamental properties of ferroelectrics, the size effect, and ferroelectric devices.

Brief functional analysis and treatment of bizarre vocalizations in an adult with schizophrenia

Variables responsible for the maintenance of bizarre vocalizations emitted by an adult diagnosed with schizophrenia were examined via a brief functional analysis, and results suggested that the behavior was maintained by attention. A treatment consisting of extinction and differential reinforcement of appropriate vocalizations was effective in reducing bizarre vocalizations and increasing appropriate vocalizations. The use of functional analysis methodology to examine variables that maintain problem behavior in this population is discussed.