Weld Line Strength in PC/ABS Injection Moldings

Polycarbonate(PC)/ABS is a very common immiscible polymer blend. The internal structure such as distribution of each component in the injection moldings of PC/ABS would be strongly affected by the processing parameters. Especially, the weld line formed by meeting two melt flows and the internal structure at the weld area would be a very complex form. By observing the etched samples of PC/ABS injection moldings using scanning electron microscopy, a weld part with fine dispersion of ABS was found in the area below V-notch. When tensile load was applied perpendicular to the weld line, the fracture initiated from the V-notch, but the crack propagated along the interface between the weld part with fine dispersion and the part behind the weld part. This leads to unique characteristics of the weld strength.

Evaluation of α2-integrin expression as a biomarker for tumor growth inhibition for the investigational integrin inhibitor E7820 in preclinical and clinical studies

E7820 is an orally active inhibitor of α(2)-integrin mRNA expression, currently tested in phases I and II. We aimed to evaluate what levels of inhibition of integrin expression are needed to achieve tumor stasis in mice, and to compare this to the level of inhibition achieved in humans. Tumor growth inhibition was measured in mice bearing a pancreatic KP-1 tumor, dosed at 12.5-200 mg/kg over 21 days. In the phase I study, E7820 was administered daily for 28 days over a range of 0-200 mg, followed by a 7-day washout period. PK-PD models were developed in NONMEM. α(2)-Integrin expression measured on platelets, corresponding to tumor stasis at t = 21 in 50% and 90% of the mice (I(int,50), I(int,90)) were calculated. It was evaluated if these levels of inhibition could be achieved in patients at tolerable doses. One hundred nineteen α(2)-Integrin measurements and 210 tumor size measurements were available from mice. The relationship between PK and α(2)-integrin expression was modeled using an indirect-effect model, subsequently linked to an exponential tumor growth model. I(inh,50) and I(inh,90) were 14.7% (RSE 7%) and 17.9% (RSE 8%). Four hundred sixty two α(2)-integrin measurements were available from 29 patients. Using the schedule of 100 mg qd (MTD), α(2)-integrin expression was inhibited more strongly than the I(int,50) and I(int,90) in greater than 95% and greater than 50% of patients, respectively. Moderate inhibition of α(2)-integrin expression corresponded to tumor stasis in mice, and similar levels could be reached in patients with the dose level of 100 mg qd.

Establishment of a quantitative mouse dorsal air sac model and its application to evaluate a new angiogenesis inhibitor

We have developed an improved mouse dorsal air sac model for quantifying in vivo tumor-induced angiogenesis. In our improved model, tumor angiogenesis is determined by measuring the blood volume in an area of skin held in contact with a tumor cell-containing chamber, using 51Cr-labeled red blood cells (RBC). The blood volume induced by murine B16-BL6 melanoma cells increased linearly with the cell number in the range from 2 x 10(5) to 5 x 10(6). Ten of 11 human tumor cell lines examined induced a significant increment in blood volume. For three representative human tumor cell lines (A549, WiDr. and HT1080 cells) that showed different angiogenic potencies, the levels of vascular endothelial growth factor (VEGF) produced by the tumor cells cultured under conditions of hypoxia and high cell density were correlated with the degree of in vivo angiogenesis. Using the improved model, it was confirmed that TNP-470, a well-known inhibitor, and borrelidin, an antibiotic from Streptomyces rochei, significantly inhibited the WiDr cell-induced angiogenesis. Borrelidin also inhibited spontaneous lung metastasis of B16-BL6 melanoma at the same dose that inhibited angiogenesis. Our results suggest that the improved mouse dorsal air sac model can be used for simple and quantitative measurement of tumor-induced angiogenesis and its inhibition.

Pediatric brain stem gliomas with the predominant symptom of sleep apnea

Two children complaining of sleep apnea presented with brain stem gliomas. In the early stage of their illness, neurological disorders were too subtle to be recognized as significant by the physicians or to be noted by the parents. Case 1 experienced an episode of unsteady gait and weakness in the bilateral arms, at the age of 5. When it recurred after 7 years of remission, the predominant symptom was sleep apnea. Case 2 exhibited nasality of speech as the earliest sign of this illness very early in his life, presumably 5 years before the diagnosis of brain stem glioma. A slight sleep apnea which developed afterwards did not draw attention of the physicians because no neurological signs other than paralyses of the bilateral soft palates were present. MRIs of the both cases revealed diffuse, infiltrating lesions in the pons, the medulla oblongata and the upper cervical spinal cord. Both cases shared some features: (1) diagnostic delay of several years from the first symptom; (2) the main lesion in the medulla oblongata, where important structures for respiratory control are identified; (3) infiltrative growth patterns in the MRI of the tumor, which might account for the uncommon clinical courses.

High expression of membrane cofactor protein of complement (CD46) in human leukaemia cell lines: implication of an alternatively spliced form containing the STA domain in CD46 up-regulation

Human membrane cofactor protein (MCP, CD46) is a receptor for the measles virus and serves as a complement regulator which protects host cells from autologous complement attack. MCP is highly polymorphic due to a variety of mRNA splice products. The levels of MCP expression on T and myeloid cell lines are usually two-eightfold higher than those on their normal counterparts, whereas Burkitt's lymphoma B cell lines express less MCP than B cell lineages carrying no EB virus. The molecule has a Ser/Thr-rich (ST) domain adjacent to the functional domain, namely short consensus repeats (SCR). The ST domain and a cytoplasmic tail (CYT) contribute to the MCP polymorphism. The ST domain is encoded by three exons (A, B and C) and major ST isoforms are STABC, STBC and STC. The authors investigated the relationship between the expression levels and isoform usage of MCP by flow cytometry using specific antibodies against STA and STC, by reverse transcriptase-polymerase chain reaction (RT-PCR) with size markers for each splice variant, and by RT-PCR/Southern blotting using a specific probe for STA. The results were (1) the profiles of mean shifts of myeloid and T cell lines were STC < STA on flow cytometry while those of B cell lines and normal blood cells were STA < STC; (2) all cell lines tested by RT-PCR expressed the messages for the isoforms STBC/CYT1, STC/CYT1, STBC/CYT2, and STC/CYT2. The band for STABC/CYT2 overlapped that for STC/CYT1, and the band for STABC/CYT1 was marginal in all cell lines examined; (3) semi-quantitative analysis of the STABC isoforms by Southern blotting indicated the presence of high levels of the STABC messages in myeloid and T-cell lines in comparison with B lymphoid cells and normal leucocytes. Thus, the quantity of MCP expressed parallels the STABC message level, which is up-regulated in T and myeloid leukaemia cell lines.

Blocking measles virus infection with a recombinant soluble form of, or monoclonal antibodies against, membrane cofactor protein of complement (CD46)

Human membrane cofactor protein (MCP, CD46) functions as an inhibitor of the complement (C) cascade to protect host cells from C attack, and as a receptor for measles virus (MV). Normal human sera contains 10-60 ng/ml of naturally produced soluble forms of MCP, which is also a cofactor for the factor I-mediated inactivation of C3b. We produced monoclonal antibodies (mAb) against MCP and a recombinant soluble form of MCP similar to the natural soluble forms, and tested their ability to block MV infection. Vero cells and CHO cells expressing human MCP were the targets. Of the antibodies tested, M75 and M177, which blocked the C regulatory activity of MCP, efficiently blocked MV infection. More than 50 micrograms/ml of the soluble form moderately blocked MV infection of CHO cells expressing MCP, but barely blocked that of Vero cells. The two mAb and the soluble form also inhibited MV H protein-mediated green monkey erythrocyte rosette formation. A quantitative analysis suggested that 30 micrograms/ml of the soluble form functionally corresponded to 0.2 microgram/ml of M177 or M75. These data established that the C regulatory function and the MV receptor function of MCP were blocked simultaneously by the individual mAb, and that soluble forms of MCP could inhibit MV infection in cells expressing human MCP, although doses far higher than the natural concentration of soluble MCP were required.

Studies on thermophile products. X. Further biological properties of isofatty acid-containing phosphatidylglycerol that enhances the induction of suppressor T cells

Isofatty acid-containing phosphatidylglycerol (Fr. 7-C), isolated from Bacillus stearothermophilus UBT8038, enhances the induction of concanavalin A (Con A)-activated suppressor T (Ts) cells in a dose dependent manner (0.01-1 microgram/ml). Its further biological properties on mouse mixed lymphocyte reaction (MLR) has been demonstrated. Fr. 7-C (0.01-1 microgram/ml) suppressed the MLR at 4 d in a dose-dependent manner when added at the start of splenocyte cultivation. Moreover, Fr. 7-C was effective in preventing the generation of cytotoxic T lymphocytes after the MLR. On the other hand, this fraction significantly enhanced the induction of Ts cells in the MLR carried out in any of the antigen-specific, antigen-nonspecific and major histocompatibility complex antigen-nonrestricted fashions. Fr. 7-C increased prostaglandin E2 (PGE2) release approximately 2-fold in the culture supernatant of Con A-activated splenocytes, and PGE2 release decreased dose-dependently when cultured with indomethacin. The inhibitory effect by Fr. 7-C on the MLR was abrogated by the addition of indomethacin. The enhancement by Fr. 7-C on Ts cell induction was blocked by indomethacin in a dose dependent manner. These results strongly suggest that Fr. 7-C suppresses the MLR via the enhancement of antigen-nonspecific Ts cell induction mediated at least partly by PGE2.

Studies on thermophile products. IX. Isofatty acid-containing phosphatidylglycerol that enhances the induction of concanavalin A-activated suppressor T cells

A new enhancer of the induction of concanavalin A (Con A)-activated suppressor T (Ts) cells has been demonstrated in the ethanolysate of Bacillus stearothermophilus UBT8038. It was purified by successive silica gel column chromatographies and identified as phosphatidylglycerol with C14:0-C18:0 isofatty acids (Fr. 7-C). Mouse splenocytes activated with Con A and Fr. 7-C (0.01-1 microgram/ml) in vitro significantly suppressed the proliferative response of syngenic splenocytes by mitogen stimulation in a dose-dependent manner, compared to those stimulated by Con A alone. The immunosuppressive response enhanced by Fr. 7-C disappeared when the cell populations of Thy-1.2 or CD8 positive lymphocytes were depleted. The result strongly suggests that Fr. 7-C is an immunosuppressive substance which enhances the induction of Con A-activated CD8 positive Ts cells.

Genetic polymorphisms of the CST2 locus coding for cystatin SA

A new genetic polymorphism of cystatin SA has been identified in human submandibular-sublingual saliva by means of basic gel electrophoresis and immunoblotting with anti-cystatin S. Two proteins, SA1 and SA2, are given by two alleles of CST2, viz., CST2*1 and CST*2. Inheritance is controlled by two codominant alleles at an autosomal locus. This hypothesis is supported by studies of 16 families 32 children. Gene frequencies for CST2*1 and CST2*2 are 0.935 and 0.065, respectively (n = 341). Eighteen amino acids determined among 20 N-terminal residues of cystatin SA2 are identical with the sequence encoded by CST2. Three forms of cystatin S (mono-phosphorylated cystatin S, di-phosphorylated cystatin S, and non-phosphorylated cystatin S) are present in the 341 saliva samples tested.

Hyperphosphorylation of a novel 80 kDa protein-tyrosine kinase similar to Ltk in a human Ki-1 lymphoma cell line, AMS3

Ki-1 lymphoma is a subtype of human malignant lymphoma characterized by the expression of CD30 (Ki-1) and a peculiar morphology. It is occasionally accompanied by a unique reciprocal chromosomal translocation t(2;5)(p23;q35). A Ki-1 lymphoma cell line, AMS3, was established by maintaining biopsied tumor cells in SCID (severe combined immunodeficiency) mice. To investigate abnormalities of the signal transduction in Ki-1 lymphomas, AMS3 lysate was immunoprecipitated with anti-phosphotyrosine monoclonal antibody, 25.2G4, and the immunoprecipitates were subjected to kinase assay and immuno-blotting with 25.2G4. A unique phosphotyrosine-containing protein of MW 80,000, designated p80, was found only in AMS3 cells and not in other cell lines or mononuclear cells from healthy donors. Subsequent amino acid sequence analysis of its tryptic digests showed that p80 was a hitherto undescribed tyrosine phosphoprotein similar to Ltk (leukocyte tyrosine kinase). Furthermore, physical interaction of p80 with CD30 was suggested from immunoprecipitation experiments with AMS3 lysates.

Studies on thermophile products. VII. Effect of 1,3-di-14-methylpentadecanoyl glycerol and its related isofatty acids on T cell proliferation in vitro

It has been found that Bacillus stearothermophilus UK563-derived immunosuppressant fraction (Fr. 5-B) consists of 1,3-diacylglycerols with saturated iso- and anteiso-type fatty acids (C14:0-C18:0) as major components. The compound, 1,3-di-14-methylpentadecanoyl glycerol (1,3-diiso C16:0 G), was synthesized and its effect on T cell proliferation was investigated together with its related isofatty acids. While 1,3-diiso C16:0 G, iso C16:0, iso C17:0, iso C17:0 methyl ester (OMe) and anteiso C17:0 OMe suppressed the mixed lymphocyte reaction (MLR) of C57BL/6 against BALB/c mice, iso C15:0, 1,3-acylglycerols with normal C16:0, C16:1 and C18:0 did not, suggesting that the presence of isofatty acids with a certain length may be essential for the suppression of MLR. 1,3-Diiso C16:0 G and iso C16:0 strongly inhibited the autologous MLR of mesenteric lymph node cells against self-antigen presenting cells in MRL/MpJ-lpr/lpr (MRL/lpr) mice, but had no effect on concavalin A-induced T cell proliferation.

Human alpha-galactosidase gene expression: significance of two peptide regions encoded by exons 1-2 and 6

Two proteins with alpha-galactosidase activity, alpha-galactosidase A (alpha-GalA) and alpha-galactosidase B (alpha-GalB, or alpha-N-acetylgalactosaminidase; alpha-NAGA) have a high homology of amino-acid sequence. Point mutations of the alpha-GalA gene have been reported only in the exons 1, 2 or 6. In this study, the exon 1-2 and/or 6 sequences of alpha-GalA cDNA were partly substituted by the corresponding regions of alpha-GalB cDNA, and three chimeric proteins were prepared by the baculovirus expression system: CMB12 with substitution at the exon 1-2 region, CMB6 at the exon 6 region, and CMB126 at both regions. They all preserved alpha-GalA antigenicity. Their kinetic properties toward 4-methylumbelliferyl alpha-galactopyranoside were compared with those of alpha-GalA. The catalytic activity was slightly low in CMB12, decreased to 1/10 in CMB6, and restored to a significant degree in CMB126. Km was more than 4-fold higher for CMB6 and CMB126 than for alpha-GalA. The pH optimum was 4.0 for both CMB12 and alpha-GalA, 4.8 for CMB6, and 4.6 for CMB126 and alpha-GalB. The catalytic activity was inhibited most by galactosamine in CMB6, and less in alpha-GalB, CMB126, alpha-GalA and CMB12 in decreasing order. The 50% inhibition concentrations of melibiose (Gal alpha 1-6Glc) and methyl alpha-galactopyranoside were 2.5- to 3-fold higher for CMB126 than for alpha-GalA. These results indicate that the low affinity of CMB126 to the substrate was caused by a reduced affinity to terminal alpha-linked galactose. We conclude that (1) the two regions encoded by exons 1-2 and 6 contribute to the alpha-galactosidic cleavage, and (2) an increase in Km of CMB6 or CMB126, with chimeric substitutions at the exon 6 region, was caused by a loss of affinity toward terminal alpha-linked galactose.

Studies on thermophile products. VI. Activation of mouse peritoneal macrophages by bis(2-hydroxyethyl) trisulfide

The biological effects of a cytotoxic substance (BS-1), isolated from Bacillus stearothermophilus UK563 and identified as bis(2-hydroxyethyl) trisulfide, on elicited mouse peritoneal macrophages induced by a casein injection, were investigated in vitro. BALB/c mouse macrophages treated or pretreated with BS-1 (1-10 micrograms/ml) showed cytotoxicity against syngeneic DBA/2 mouse P815 mastocytoma. BS-1 also showed weak cytotoxicity directly against P815 in the absence of macrophages. BS-1 significantly increased the glucose consumption of macrophages without producing cytotoxicity. This trisulfide compound increased nitric oxide formation, interleukin-1 production and prostaglandin E2 release in macrophages. It did not, however, increase the production of active oxygen species in macrophages, but it reduced cytochrome c in the presence of phagocytes. These results indicate that BS-1 activates macrophages to the cytolytic stage.

Tumor necrosis factor-alpha induces expression of monocyte chemoattractant JE via fos and jun genes in clonal osteoblastic MC3T3-E1 cells

The mechanism by which circulating monocytes are attracted to sites of bone remodeling is unknown. We now report that tumor necrosis factor-alpha (TNF-alpha), a potent osteotrophic cytokine, was stimulatory for expression of the monocyte chemoattractant JE gene in osteoblastic MC3T3-E1 cells. TNF-alpha stimulated this JE gene expression transcriptionally. The presence of JE gene product in conditioned medium of the cytokine-treated cells was evidenced by an immunoprecipitation assay with antiserum specific for JE/MCP-1. The stimulated JE gene expression was markedly inhibited by H-7, a potent inhibitor of protein kinase C. Phorbol 12-myristate 13-acetate induced the JE gene expression, and the cytokine-induced JE gene expression was down-regulated by the phorbol ester pretreatment. TNF-alpha induced expression of both early protooncogenes, c-fos and c-jun, in the cells. Antisense oligonucleotides to these oncogenes significantly inhibited the cytokine-induced monocyte chemotactic activity. Furthermore, curcumin, a specific inhibitor of c-jun/AP-1, markedly inhibited JE gene expression and monocyte chemotactic activity induced by the cytokine. These results suggest that TNF-alpha may contribute to the regulation of remodeling and inflammation of bone tissues through the JE gene product.

Identification of HS1 protein as a major substrate of protein-tyrosine kinase(s) upon B-cell antigen receptor-mediated signaling

Crosslinking of membrane-bound immunoglobulins, which are B-cell antigen receptors, causes proliferation and differentiation of B cells or inhibition of their growth. The receptor-mediated signaling involves tyrosine phosphorylation of cellular proteins and rapid activation of Src-like kinases. The amino acid sequences of five proteolytic peptides of p75, a major substrate of protein-tyrosine(s) in the signaling, showed that p75 is the human HS1 gene product. The HS1 gene is expressed specifically in hematopoietic cells and encodes p75HS1, which carries both helix-turn-helix and Src homology 3 motifs. p75HS1 showed rapid tyrosine phosphorylation and association with a Src-like kinase, Lyn, after crosslinking of membrane-bound IgM. Thus, p75HS1 may be an important substrate of Lyn and possibly other protein-tyrosine kinases upon B-cell antigen receptor-mediated signaling.

Acinic cell carcinoma of the parapharyngeal space: case report

We describe a case of acinic cell carcinoma (ACC) of the parapharyngeal space in a 58-year-old woman. A tumor originating from the deep lobe of the parotid gland was totally excised by an external cervical approach. The occurrence of ACC in the parapharyngeal space is extremely rare. We discuss the management, especially surgical procedure, of ACC in this area.

Fate of odontoblasts and blood capillaries in the incisal region of the rat incisor pulp

Transmission electron microscopy of thin sections of the rat incisor pulp revealed that in the middle region of the incisor there were fenestrated capillaries in the "predentinal plexus" and that this region contained the tallest odontoblasts. The odontoblasts gradually became shortened in the incisal part of this region; the fenestrated capillaries in the predentinal plexus changed to continuous type capillaries. Almost all the odontoblasts had degenerated near the incisal end of the tooth. The predentinal plexus disappeared in this region, but the "subodontoblastic capillary plexus" persisted. In a specific region just beneath the worn incisal end, numerous macrophages and polymorphonuclear neutrophils appeared and scavenged the degenerating cells, possibly including the odontoblasts.

A long synthetic peptide containing a nuclear localization signal and its flanking sequences of SV40 T-antigen directs the transport of IgM into the nucleus efficiently

Synthetic short peptides containing only the nuclear localization signal (NLS) direct the transport of nonnuclear proteins into the nucleus. As a conjugate of the synthetic peptide with immunoglobulin M (IgM) did not enter the nucleus, there was believed to be a size limit for nuclear transport of NLS-conjugated proteins. However, we found that IgM conjugated with purified nucleoplasmin, a nuclear protein of Xenopus oocytes, rapidly accumulated in the nucleus. For direct comparison with the short peptide, we prepared a long peptide containing the NLS and its flanking sequences of SV40 large T-antigen and its mutated long peptide, in which possible phosphorylation sites located at the amino terminal of the NLS were changed to alanine. Kinetic experiments showed that wild-type long peptide-IgM conjugates were almost entirely taken up into the nucleus within 30 min after their injection, whereas almost 60 min was required for the mutated long peptide-IgM conjugates to enter the nucleus of all the cells examined, and there was no apparent accumulation of short peptide-IgM conjugates in the nucleus within 60 min. These results indicate that even when the kinetics of transport are affected by amino acid substitutions, the long peptide directs the transport of large molecules such as IgM into the nucleus.

Studies on thermophile products. IV. Structural elucidation of cytotoxic substance, BS-1, derived from Bacillus stearothermophilus

A new cytotoxic substance designated as BS-1 was isolated from the autolysate and culture filtrate of Bacillus stearothermophilus UK563. On the basis of spectral data, the structure of BS-1 was determined as bis(2-hydroxyethyl) trisulfide and confirmed by direct comparison with the synthetic compound. BS-1 exhibited potent cytotoxicity against leukemia P388-D1, leukemia P388, mastocytoma P815, lymphoma EL4 and lymphoma MOLT4.

Analysis of C5b-8 binding sites in the C9 molecule using monoclonal antibodies: participation of two separate epitopes of C9 in C5b-8 binding

C5b-8 binding sites in C9 were examined using mAbs raised against C9. Among 16 mAbs, two, designated P40 and X197, blocked C9-mediated EAC1-8 lysis. C9 pretreated with the mAbs failed to bind to EAC1-8 at 4 degrees C. In addition, the mAbs became inaccessible to the C9 that had been incorporated into EAC1-8 at 4 degrees C. These findings suggest that C9 binding to EAC1-8, but not its membrane spanning or polymerization, is blocked by mAbs. By immunoblotting analysis using alpha-thrombin proteolytic fragments derived from C9 [a N-terminal fragment of mol. wt 25,000 (C9a) and a C-terminal one of mol. wt 37,000 (C9b)] and tryptic fragments of C9 (mol. wts 53,000 (C9a') and 20,000 (C9b')), the epitopes of P40 and X197 were mapped to the N-terminal and C-terminal regions of C9b, respectively. Both P40 and X197 bound to the C9 polymerized with Zn2+ in the fluid phase, whereas X197 but not P40 reacted with the membrane attack complex (MAC) formed on membranes. The results suggest that two distinct epitopes are involved in C9 binding to EAC1-8, and behave in a different manner for globular C9 bound to EAC1-8 at 4 degrees C, C9 assembled in MAC, or poly-C9 induced by Zn2+. These mAbs may be useful in clarifying the conformational states of C9 and in analyzing the molecular interaction between C9 and its inhibitors.

Isolation of a new antitumor substance from Bacillus stearothermophilus

A new antitumor substance, BS-1, was isolated from the autolysate and culture filtrate of Bacillus stearothermophilus UK563 by ethylacetate extraction and HPLC. BS-1 inhibited the proliferation of mouse macrophage-like cells, P388-D1 (IC50: 4 micrograms/ml) and mouse mastocytoma, P-815 (IC50: 0.6 microgram/ml), but not that of Balb/c 3T3.

A protein recognized by antibodies to Asp-Asp-Asp-Glu-Asp shows specific binding activity to heterogeneous nuclear transport signals

Nuclear proteins contain a signal, termed the nuclear transport signal, that specifies their selective transport into the nucleus. Previously we reported that antibodies to Asp-Asp-Asp-Glu-Asp (DDDED) inhibited nuclear transport of nuclear proteins in vivo. We therefore tried to detect a cellular receptor of nuclear transport signals as a protein that reacted with both anti-DDDED antibody and nuclear transport signal sequences. Using two steps of affinity chromatography, anti-DDDED-Sepharose and nucleoplasmin-Sepharose, we obtained a protein of 69 kDa (p69) from the nuclear pore fraction that showed these characters. This p69 recognized by anti-DDDED antibody interacted specifically with SV40 large T antigen and nucleoplasmin transport signals.

Protein disulfide-isomerase in rat exocrine pancreatic cells is exported from the endoplasmic reticulum despite possessing the retention signal

Recently we found by immunogold electron microscopy that protein disulfide-isomerase (PDI), a major resident protein in the lumen of the endoplasmic reticulum (ER) of many cells, is exceptionally localized in rat exocrine pancreatic cells not only in the ER but also in plasma membranes and other organelles along secretory pathway (Akagi, S., Yamamoto, A., Yoshimori, T., Masaki, R., Ogawa, R., and Tashiro, Y. (1988) J. Histochem. Cytochem. 36, 1069-1074). These observations suggest that another type of PDI, e.g. one with a defective ER retention signal, might exist and be transported in the exocrine pancreatic cells. We therefore compared biochemical and immunochemical properties of the transported PDI with the authentic ER resident PDI. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis, peptide mapping, urea-polyacrylamide gel electrophoresis, and isoelectric focusing showed that the former was indistinguishable from the latter. We prepared a polyclonal antibody against the synthetic hexapeptide, which corresponds to the carboxyl terminus of PDI containing the putative ER retention signal "KDEL." The epitopes of this antibody (anti-KDEL antibody) were located within the KDEL sequence. Anti-KDEL antibody reacted with PDI in both the plasma membranes and the ER of rat pancreatic cells in immunoblot analysis as well as in immunogold electron microscopy. These results suggest that PDI exported from the ER to the plasma membranes in rat exocrine pancreatic cells possesses the KDEL sequence.

Evidence for an intraluminal mediator in rat pancreatic enzyme secretion: reconstitution of the pancreatic response with dietary protein, trypsin and the monitor peptide

New evidence has been obtained suggesting that the "monitor" peptide is an essential intraluminal mediator in the stimulation of pancreatic enzyme secretion in response to protein intake in rats. Experiments were performed in vivo using a mixture of 50 mg of ovalbumin, alpha-lactalbumin or casein, 2 micrograms of purified protease-sensitive, cholecystokinin-releasing monitor peptide and 1 mg of porcine trypsin which was infused by cannula into the duodenum of atropine-treated rats. The small intestine had previously been washed with bicarbonate to eliminate proteases and the pancreatic juice was diverted. The amount of trypsin secreted in 2 h was comparable to that of rats in which the pancreatic juice was returned into the duodenum. However, in the presence of a monitor peptide--specific antibody which recognizes the N-terminal region of the peptide, the monitor peptide did not induce any pancreatic response. Therefore, the characteristic pattern of pancreatic enzyme secretion in response to protein intake can be reproduced by infusing only three components--dietary proteins, porcine trypsin and the purified monitor peptide.

Experimental observation of plastic deformation areas, using an acoustic microscope

Novel techniques are described for the observation of plastic deformation areas by using an acoustic microscope. On a test piece subjected to plastic deformation, an area was found that had an abnormal contrast in the crystal grain and a pointed end at the V notch. Calculation of the propagation velocity of the surface acoustic wave (SAW) showed a difference of several percent between this area and the rest of the test piece. It has been presumed that this difference reflects the local plastic deformation, and that the abnormal contrast area corresponds to the image of the two-dimensionally distributed plastic deformation area of metals.

Measurement of a damaged layer thickness with reflection acoustic microscope

An acoustic microscope was used for determining the frequency dependence of surface acoustic wave (SAW) velocity on a specimen whose silicon single-crystal surface was machined under various conditions. Consequently, thickness of the damaged layers could be estimated from the curvature points of frequency dispersion curves of the SAW velocity. It was revealed that thicknesses of the damaged layers can be estimated through rough approximation by about one-half the wavelength determined by the frequency at curvature points. From specimens possessing two damaged layers, frequency dispersion curves with two curvature lines can be obtained. From the curvature point at high frequencies the thickness of the top damaged layer can be determined. On the other hand, from the curvature point at low frequencies, the thickness of the inner damaged layer can also be determined. By choosing an acoustic lens as the condition for exciting SAWs, images can be observed while varying the frequency. From observation results obtained with this method, the distribution in the depth direction can be clarified.

A monoclonal antibody against dentin phosphophoryn recognizes a bone protein(s) appearing at the beginning of ossification

Decalcified and nondecalcified sections of fetal bovine tibia were stained immunohistochemically with a monoclonal antibody against dentin phosphophoryn. In the epiphyseal portion of the long bone, osteoblasts, osteocytes and the bone matrix were stained, but chondrocytes and the cartilage matrix were not. Similar staining was observed in the epiphyseal and diaphyseal portions of bones. These findings suggest that a protein(s) with the same epitope as phosphophoryn may be synthesized and secreted by osteoblasts at the beginning of ossification and may be involved in mineralization of bone tissue. On Western blots of proteins extracted from fetal bovine bone, the antibody reacted with two bands of molecular weights of about 71,000 and 63,000. These proteins and antibody(s) to the proteins may be useful for detection of the phenotype of osteogenesis.

Preparation of a verifiable peptide-protein immunogen: direction-controlled conjugation of a synthetic fragment of the monitor peptide with myoglobin and application for sequence analysis

A useful method for preparing a synthetic peptide-carrying protein for specific antibody production was established. The monitor peptide is a trypsin-sensitive cholecystokinin-releasing peptide purified from rat pancreatic juice on the basis of its stimulatory activity toward pancreatic enzyme secretion. The NH2-terminus fragment of the monitor peptide (residues 1-14) was synthesized by a solid phase method. Cysteine at the COOH terminus of the fragment was conjugated with amino groups of myoglobin using a hetero-bifunctional reagent. Sequence analysis of the fragment-myoglobin conjugate indicated that the peptide/myoglobin conjugation ratio was about 1/1 (mol/mol). Antiserum against the conjugate from a rabbit effectively abolished the stimulatory activity of the monitor peptide in the rat small intestine.

Audiological characteristics of hearing loss following meningitis

Meningitis is one of the leading causes of acquired sensorineural hearing loss in childhood, and many retrospective and prospective studies and case reports have been published. However, they have seldom discussed the nature of postmeningitic hearing loss from the audiological point of view. This study reports the results of audiological examinations performed on 5 patients suffering from hearing loss following meningitis. Extremely poor word discrimination scores as compared with pure-tone audiograms were common in all 5 cases. Type IV Békésy tracings were observed in 2 cases. Discrepancies between pure-tone audiograms and subjective hearing sensation and between pure-tone audiograms and ABR recordings were noted in 2 cases. These results suggest that varying degrees of retrocochlear involvement complicating the inner ear damage are the audiological characteristics of hearing loss following meningitis.

[Effects of gamma-oryzanol on the movements of stomach and ileum in the dog (author's transl)]

Gastric and ileal movements were measured after administration of gamma-Oryzanol in the dog. 1. Gastric and ileal movement were enhanced after intravenous administration of 1 mg/kg body weight of gamma-Oryzanol. The higher dose of gamma-Oryzanol produced the shorter latency of these enhanced movements and thereafter, induced the inhibition of these movements. 2. When bilateral vagal nerves and the splanchnic nerves were previously transected or administered atropine, no enhancement of the gastric and ileal movement were observed by administration of gamma-Oryzanol. Furthermore, these enhanced movement produced with gamma-Oryzanol were abolished by atropine injection during these enhanced movement. 3. The inhibitory movement of the stomach and the ileum produced by administration of gamma-Oryzanol of 10 mg/kg body weight were reversely existed by the transection of vagal nerves in the cervical region or by administration of quinidine. These results indicate that gamma-Oryzanol produces the enhancement as well as inhibition of gastric and ileal movements. These effects may be produced by reaction to the central nervous system of the gastric and ileal movements.

Effects of distension on mesenteric blood flow and O2 saturation of venous blood in the dog intestinal loop

Arterial and venous blood flow and oxygen saturation of the venous blood in the mesenteric vessels arising from single mesenteric artery and vein to the intestinal loop in anesthetized dogs were measured simultaneously with systemic arterial blood pressure during distension of this loop. Mesenteric arterial blood flow decreased to the zero level, while mesenteric venous outflow increased to about twice the quiescent level at the onset of elevation of intraluminal pressure. However, during distension, the decreased arterial blood flow tended to increase, but the increased venous flow was reduced to one half of the quiescent level. Oxygen saturation of venous blood diminished initially and then increased progressively during distension. At the end of distension venous outflow stopped temporarily. After suspension of distension, arterial and venous flow and oxygen saturation increased beyond the quiescent level. These results may suggest that there is a by-pass or A-V anastomosis which cannot be compressed mechanically by elevation of intraluminal pressure.

Atropine-resistant excitation of motility of the dog stomach and colon induced by stimulation of the extrinsic nerves and their centers

The atropine-resistant contraction of the alimentary canal, first reported by CAMPBELL (1966) and subsequently confirmed by others, was examined in dog in vivo. The gastric and colonic motor excitations were examined by stimulating the extrinsic nerves, the medulla oblongata or the spinal cord and its roots. Prolonged stimulation of the vagus, medulla oblongata or splanchnic nerve, thoracic cord and its dorsal root produced excitation of the gastric motility even after intravenous injection of sufficient atropine, although the intensity and frequency of peristalsis were slightly reduced. Prolonged latent periods were characteristic of the atropine-resistant excitation in the stomach, the latency being 29.8--49.4 sec as compared to 2.3--14.5 sec in control (without atropine). On the other hand, the colonic excitation induced by the stimulation of the pelvic nerve, or sacral cord and its ventral root was not inhibited by atropine; no prolongation in latency and reduction of peristalsis was observed.

Influence of intestinal inhibitory reflex on mesenteric blood flow through an intestinal segment of the dog

The variations in both tonus and rhythmical motility of the intestinal musculature are known to affect profoundly intestinal blood flow. In the present study, the influence of marked reflex inhibition of intestinal tone on the blood flow through an intestinal segment was investigated in the dog. Experiments were performed under conditions of both normal circulation and cross-circulation. Inhibitory reflex was elicited by elevating the intraluminal pressure of a loop or by electrical stimulation of the intestinal wall. Fluctuations of blood flow during the intestinal inhibitory reflex were observed with normal circulation. Arterial and venous blood flows decreased in the initial period of intestinal relaxation, and recovered within 30 sec although reflex inhibition still remained. This is an autoregulatory escape phenomenon. In successive periods, arterial and venous blood flows decreased again due to "the venous-arteriolar response" and then recovered to the quiescent level. The decrease in venous blood flow corresponded to an increase of the degree of oxygen saturation in the venous blood. The decreases in arterial and venous blood flows were observed during the inhibitory reflex even when the intestinal circulation was maintained by the cross-circulation. Two different patterns, i.e., the parallel and reversed patterns, were distinguished in correlation with venous blood flow and oxygen saturation. The autoregulatory escape phenomenon could not be elicited in the experiments in the cross-circulation system because variation of the systemic blood pressure during inhibitory reflex was limited to +/-4%.

[Effects of physostigmine and duvadilan on an atropine-resistant contraction of dog's stomach (author's transl)]

Effects of atropine, physostigmine, duvadilan and tetrodotoxin on the mechanical activity of the longitudinal muscle preparation of dog's stomach in vitro experiments and on the motility of stomach in the same animal in vivo experiments were investigated. 1. The latency of an atropine-resistant contraction which was produced by stimulation of vagus nerve was increased in period in accordance with the augmentation of concentration of atropine in vitro experiments. 2. Physostigmine reconstructed the atropine-resistant contraction which was abolished by duvadilan as well as the cholinergic contraction which was abolished by atropine in vivo experiments. 3. Duvadilan abolished the cholinergic and atropine-resistant contractions in vitro, but in vivo experiments duvadilan abolished only the atropine-resistant contraction. 4. An atropine-resistant contraction was completely abolished by administration of tetrodotoxin. But the direct electrical stimulation of the muscle caused the contraction of it which was blocked by tetrodotoxin.