Epitope-specific impairment of production of antibody against merozoite surface glycoprotein 1 of Plasmodium falciparum in symptomatic patients with malaria

We analyzed the relationships between levels of antibody specific for merozoite surface glycoprotein-1 (MSP1) of Plasmodium falciparum and clinical manifestations in humans. We prepared recombinant MSP1 proteins representing block 3 (M3), block 6 (M6), blocks 1–6 (M1/6), and block 17. When we divided the slide-positive individuals in Guadalcanal into symptomatic and asymptomatic groups, the former group showed lower IgG levels against M6 and block 17, but not against M3, than did the asymptomatic group (P < 0.01). The possibility of nonspecific suppression was unlikely, given that the levels of antibody against poliomyelitis virus observed in the two groups were almost the same. Among the IgG subclasses tested, production of cytophilic IgG₃ seemed to be dominant. When we analyzed epitopes recognized by antibodies against block 17, a peptide (SSSNFLGIS) was preferentially recognized by sera from asymptomatic individuals. These results suggest that clinical symptoms occurring during falciparum malaria seem to be associated with the development of levels of antibody against particular epitopes on MSP1, which is under the control of an immunoregulatory mechanism. Received: 1 October 1999 / Accepted: 21 October 1999     

Orientational behavior of side-chain liquid-crystalline polysiloxanes deduced from measurements of second harmonic generation

Side-chain functionalized polysiloxanes were prepared via polymer-analogous esterification of poly[(3-chloroformylpropyl)methylsiloxane] with 4-(4-hydroxyphenylazo)nitrobenzene ( P1 ), 4-[4-(ω-hydroxyalkyloxy)phenylazo]nitrobenzene ( P2 – P4 ), 4-{4-[N-(2-hydroxyethyl)-N-methyl]anilinoazo}nitrobenzene ( P5 ), 4-(4-hydroxypiperidino)nitrobenzene ( P6 ), or 4-[4-(2-hydroxyethyl)piperidino]nitrobenzene ( P7 )., P1 , P3 , P4 and P5 exhibit liquid crystallinity, as deduced from differential scanning calorimetry, polarized microscopic observations and X-ray diffraction measurements. The liquid-crystalline phase of P1 and P5 is a nematic phase, and that of P3 and P4 is a smectic one. The second harmonic generation (SHG) measurement of a spin-coated film of P1 was carried out by the Maker fringe method using a Q-switched Nd:YAG laser (1064 nm). The SHG profile after the heat treatment of a spin-coated film suggests a perpendicular orientation of the mesogenic molecules to the glass substrate. The SH light intensity of a corona-poled film was 20-fold higher than that of a film which was only heated, though no differences were observed in their UV-vis absorption spectra. These findings suggest that the mesogenic-molecular dipole moments are aligned to the same direction in the crystalline or liquid-crystalline phase by a poling treatment.     

Immunohistochemical Investigation of Vimentin, Neuron-specific Enolase, α1-antichymotrypsin and α1-antitrypsin in Adenoid Cystic Carcinoma of the Salivary Gland

Fifty-four adenoid cystic carcinomas (ACC) arising in major and minor salivary glands as well as in normal salivary glands were studied by immunohistochemistry for the presence of vimentin, neuron specific enolase (NSE), α₁-antichymotrypsin (α₁-ACT) and α₁-_- antitrypsin (α₁-_- AT). Five patterns of histological differentiation were found in ACC, and for the cellular components of each, it was possible to establish a special immunohistochemical profile. In ACC, vimentin-positive cells were observed in the outer tubular, cyst-lining and small angular cells. NSE was positive in the myoepithelial cells of normal salivary gland. Neoplastic cells of ACC showed NSE positivity mainly in the small angular cells and partly in the duct luminal cells. α₁-ACT was localized in the intercalated duct cells and serous acinar cells of normal salivary gland, and in the duct luminal cells of ACC. α₁-AT could not be detected in any of the epithelial cells of normal salivary gland. In ACC, eosinophilic hyaline material in the cribriform spaces was positive for α₁-AT, but no positivity was demonstrated in tumor cells. The present study showed that there are at least two populations of tumor cells in ACC: duct luminal cells that express α₁-ACT, thus indicating their ductal character, and small angular cells that express vimentin, characteristic of non-luminal cells. Moreover, our results indicate that α₁-AT is a useful marker of basement membrane-like material.     

Demonstration of Borna disease virus (BDV) in specific regions of the brain from horses positive for serum antibodies to BDV but negative for BDV RNA in the blood and internal organs

Sero- and molecular-epidemiological studies on Borna disease virus (BDV) infection show that BDV RNA is not always detected in the peripheral blood mononuclear cells (PBMCs) from serum anti-BDV antibody-positive individuals such as horses, sheep, cattle, cats, and humans. In this study we demonstrated BDV RNA signals by polymerase chain reaction only in restricted regions of the brain from horses with locomotor disease. Four of six horses examined showed apparently positive reactions for anti-BDV antibodies. Specific regions of the brain of these four horses were positive for BDV RNA but the internal organs, lymph nodes, and PBMCs were negative. Histological studies of their brains revealed no apparent histological abnormalities such as inflammatory reactions. These results suggest that BDV chronically infects certain restricted regions of brain in seropositive horses. Received: 6 January 1997     

Usefulness of a stature-based standard of skinfold thickness,especially for short children

Skinfold thicknessess (SFT) were measured at ulnar, triceps, subscapular and suprailiac sites in 730 boys and 724 girls (age 3–12 years) whose stature ranged from 100 to 150 cm and whose weight was within ±20% of the average. Means and standard deviation (SD) were calculated after logarithmic transformation of the original skinfold readings to demonstrate stature-based standards of SFT in Japanese children. The means of SFT exhibited nadirs (boys/ girls: ulnar 5.1/5.9 mm, triceps 7.9/9.5 mm, subscapular 4.9/6.1 mm, suprailiac 4.5/6.2 mm) in subjects 110–115 cm tall except for ulnar SFT in girls. SFT values increased as children increased in stature. Standard deviations of SFT at the four sites in short children (staturte < mean ?1 SD) were estimated using the stature-based standard as well as an age-based standard. Susms of the SDs assessed by the age-based standard were significantly smaller than those assessed by the stature-based standard in boys (P < 0.05) and girls (P < 0.01) with short stature, suggesting that SFT in short children was falsely understimated by the age-based standard. Thus, the stature-based standard is beneficial for the assessment of SFT, especially in children whose stature is below the mean ?-1 SD. © 1995 Wiley-Liss, Inc.     

Expression of serotonin2A receptors in Purkinje cells of the developing rat cerebellum

Previous physiological and pharmacological studies have shown that the serotonin_2A (5-HT_2A) receptor is involved in cerebellar functions. However, the expression of 5-HT_2A receptors in the developing cerebellum has not been elucidated to date. In the present immunohistochemical study, we examined developmental changes of the distribution of 5-HT_2A receptors in Purkinje cells of the rat cerebellum from embryonic day 18 (E18) to postnatal day 21 (P21). The weak immunoreaction to 5-HT_2A receptors was found in the deep cerebellar nuclei on E19. In the cerebellar cortex of the hemisphere and the posterior vermis, somata of Purkinje cells became weakly immunoreactive on P0. With the dendritic elongation and arborization, the immunoreaction appeared in the proximal parts of Purkinje cell dendrites. Distal parts of the dendrites became immunoreactive after P12, and were strongly immunolabeled by P21. The present study may provide a structural basis to investigate the roles of 5-HT_2A receptors during the cerebellar development.     

Characterization of factor XII Tenri, a rare CRM-negative factor XII deficiency

Factor XII Tenri (Y34C), a rare cross-reacting material (CRM)-negative factor XII deficiency, was identified in a 71-yr-old Japanese woman with angina pectoris. In the patient's plasma, factor XII activity and antigen levels were only 1.6% and 5.0%, respectively, of those seen in a normal subject. Immunoblot analysis showed that the secreted factor XII Tenri existed not only as a monomer (76 kDa), but also in complexes with apparent molecular weights of approximately 115, 140, 190, 215, and 225 kDa. After reduction with 2-mercaptoethanol, the factor XII Tenri contained in the complexes was completely converted to monomeric form on immunoblot patterns. It appeared that some of the secreted factor XII Tenri formed several types of disulfide-linked complexes, including a factor XII-alpha1-microglobulin complex, through a newly generated Cys residue. The monomeric form of factor XII Tenri, like normal factor XII, was degraded into 2 major fragments with molecular weights of approximately 45 kDa and 30 kDa following mixing with activated partial-thromboplastin-time measuring reagent (cephalin and ellagic acid), whereas the factor XII Tenri that formed the complexes was not. This indicates that the factor XII Tenri present in disulfide-linked complexes with other proteins (and itself) is not converted to active forms, suggesting that attached proteins obstruct or delay the activation of factor XII via an inhibition of its binding to a negatively charged surface in vitro.     

Mechanisms responsible for delayed and immediate hemolytic transfusion reactions in a patient with anti-E + Jk(b)+ Di(b) and anti-HLA alloantibodies

Immediate hemolytic transfusion reactions (IHTR) occurred in the course of delayed hemolytic transfusion reactions (DHTR). An 84-year-old man had received a blood transfusion 20 years ago. Progressive anemia developed, because of continuous bleeding from a bladder tumor. He was transfused with concentrated red blood cells (CRC) which were Rh-E antigen negative, because he had anti-E antibodies (day 0). He received CRC on day 3, and underwent resection of bladder tumor on day 6. Although crossmatch-compatible CRCs were prepared for the operation, those were not required and were kept in a refrigerator in the ward. On day 9, when a CRC kept in the ward was transfused, he suddenly had a IHTR. In order to analyze a mechanism of IHTR, the anti-Jk(b) and anti-Di(b) antibodies, anti-HLA antibodies and the concentrations of inflammatory cytokines were measured in serum samples. The anti-Jk(b) and anti-Di(b) antibodies increased prior to IHTR experienced on day 9. The concentrations of IL-6 and IL-1beta increased from day 2, while the concentration of IL-8 increased from day 7. The anti-HLA class I antibody could be detected 2 days before IHTR. Thus, the anti-Jk(b) and anti-Di(b) antibodies induced the production of inflammatory cytokines and symptoms of DHTR and IHTR. The anti-HLA class I antibody could be produced in spite of using the filer for removing leukocytes, and may take part in the induction of IHTR. Further, blood products should be transfused soon after completing a crossmatch test in patients with anti-RBC alloantibodies.     

Expression of gastrin-releasing peptide (GRP) in the bovine uterus during the estrous cycle

Gastrin-releasing peptide (GRP) has been proposed as a novel regulatory peptide in the reproductive tract. We previously demonstrated that GRP immunoreactivities are found predominantly in the uterine gland epithelial cells of nonpregnant and pregnant cows. The present study focused on the distribution of GRP immunoreactivity and the expression of GRP mRNA in the bovine endometrium during the estrous cycle. Tissues were collected from 21 uterine horns and bodies during the estrous cycle. RT-PCR showed the expected GRP mRNA fragments (284 bp) in the tissues from all stages of the cycle. In situ hybridization results ascertained the expression of the GRP mRNA in the uterine gland epithelial cells and superficial epithelial cells of the endometrium. Positive staining of GRP immunoreactivity in the uterine gland epithelial cells was detected in both the uterine horn and body from all stages of the cycle. In metestrus and diestrus stages, GRP was also detected in the superficial epithelial cells of horn, but not in the body. The degrees of GRP mRNA expression and intensities of GRP immunoreactivity in the endometrium increased from proestrus to diestrus stages. These findings suggest that GRP may be important both in the endometrial remodeling during the estrous cycle and in the implantation and development of blastocysts.