[A Trial of Practical Training on Online Medication Instructions in Clinical Preparatory Education: Development of Human Resources to Provide New Forms of Medical Care after the COVID-19 Pandemic]

The coronavirus disease 2019 (COVID-19) pandemic has considerably affected several social services. The Ministry of Health, Labour, and Welfare has partially revised the Pharmaceuticals and Medical Devices Law and established legislations on permanent online medication instructions. Based on these social needs, the development of human resources to provide online medication instructions is vital. Therefore, we developed a training program for providing online medication instructions in preparatory clinical education. Pharmacy students who had conducted medical interviews with standardized patients participated in the training. Educational outcomes were evaluated using an objective multiple-choice test and free description before and after practical training. The median number of correct answers on objective tests on the legislation on online medication instructions increased significantly. Based on the free description analysis, students were able to comprehend the influence of communication environment on the quality of medication instructions. Based on the results of the direct evaluation using objective testing and indirect evaluation by analyzing the free descriptions, they also acquired the skills necessary for providing online medication instructions. Therefore, this training program can contribute to mastering the provision of online medication instructions.

Hepatoprotective Activity of Yellow Chinese Chive against Acetaminophen-Induced Acute Liver Injury via Nrf2 Signaling Pathway

Glutathione, the most abundant intracellular antioxidant, protects cells against reactive oxygen species induced oxidative stress and regulates intracellular redox status. We previously demonstrated that yellow Chinese chive (ki-nira) increased the intracellular glutathione levels. Acetaminophen (APAP) is a commonly used analgesic. However, an overdose of APAP causes severe hepatotoxicity via depletion of the hepatic glutathione. In this study, we investigated the hepatoprotective effects of yellow Chinese chive extract (YCE) against APAP-induced hepatotoxicity in mice. YCE (25 or 100 mg/kg) was administered once daily for 7 d, and then APAP (700 mg/kg) was injected at 6 h before the mice were sacrificed. APAP treatment markedly increased the serum biological markers of liver injury such as alanine aminotransferase, aspartate aminotransferase, lactate dehydrogenase, and alkaline phosphatase. Pretreatment with YCE significantly prevented the increases in the serum levels of these enzymes. Histopathological evaluation of the livers also revealed that YCE prevented APAP-induced centrilobular necrosis. Pretreatment with YCE dose-dependently elevated glutathione levels, but the difference was not significant. Nuclear factor erythroid 2-related factor 2 (Nrf2) plays a critical role in APAP-induced hepatotoxicity by regulating the antioxidant defense system. Therefore, we investigated the expression of Nrf2 and its target antioxidant enzyme. YCE led to an increased expression of Nrf2 and its target antioxidant enzymes, NAD(P)H quinone oxidoreductase 1 (NQO1), glutathione peroxidase (GPx), cystine uptake transporter (xCT), especially hemeoxygenase-1 (HO-1) in mice livers. These results suggest that YCE could induce HO-1 expression via activation of the Nrf2 antioxidant pathway, and protect against APAP-induced hepatotoxicity in mice.

Protective Effects of Rice Peptide Oryza Peptide-P60 against Oxidative Injury through Activation of Nrf2 Signaling Pathway In Vitro and In Vivo

We previously showed that commercially available rice peptide Oryza Peptide-P60 (OP60) increased the intracellular glutathione levels. This study aimed to evaluate the antioxidant potential of this peptide and assess its mechanism of action. Pretreatment of HepG2 cells with OP60 reduced the cytotoxicity caused by H₂O₂ or acetaminophen (APAP) (47.7 ± 1.3% or 12.2 ± 1.3% of the cytotoxicity for 5 mg/mL OP60 pretreatment compared to that in H₂O₂- or APAP-treated groups, respectively; p < 0.01) through the restoration of glutathione homeostasis. Moreover, OP60 elevated the mRNA level of genes encoding heavy and light subunits of γ-glutamylcysteine synthetase (γ-GCS) by 2.9 ± 0.1-fold and 2.7 ± 0.2-fold (p < 0.001), respectively, at 8 h and also increased the level of mRNA encoding other antioxidant enzymes. Besides, OP60 promoted Nrf2 nuclear translocation by 2.2 ± 0.3-fold (p < 0.05) after 8 h. Conversely, knockdown of Nrf2 inhibited the increase of the intracellular glutathione levels and suppressed the induction of antioxidant enzyme expression by OP60. In animal studies, OP60 prevented APAP-induced liver injury by suppressing glutathione depletion (from 0.19 ± 0.02 mmol/mg protein to 0.90 ± 0.02 mmol/mg protein; p < 0.01, by pretreatment with 500 mg/kg OP60) and increasing heavy subunit of γ-GCS and heme oxygenase-1 expression in the liver. Our results indicated that OP60 exhibits a cytoprotective effect via the Nrf2 signaling pathway and is one of the few peptides with excellent antioxidant properties.

Sake lees hydrolysate protects against acetaminophen-induced hepatotoxicity via activation of the Nrf2 antioxidant pathway

Acetaminophen is a commonly used analgesic. However, an overdose of acetaminophen causes severe hepatotoxicity via depletion of hepatic glutathione. Here, we investigated the protective effects of sake lees hydrolysate against acetaminophen-induced hepatotoxicity in mice. Sake lees hydrolysate was administered orally to ICR mice for seven days. Six hours after acetaminophen treatment, the mice were sacrificed, and blood and liver samples were collected for analysis. Treatment with acetaminophen markedly increased the levels of serum alanine aminotransferase, aspartate aminotransferase, lactate dehydrogenase, and alkaline phosphatase. Pretreatment with sake lees hydrolysate significantly prevented the increases in the serum levels of these enzymes and inhibited acetaminophen-mediated glutathione depletion. In addition, histopathological evaluation of the livers also revealed that sake lees hydrolysate prevented acetaminophen-induced centrilobular necrosis. The expression of γ-glutamylcysteine synthetase (γ-GCS), hemeoxygenase-1 (HO-1) and nuclear factor erythroid 2-related factor 2 (Nrf2) in the liver were decreased after acetaminophen treatment, whereas pretreatment with sake lees hydrolysate led to an increased expression of all three proteins. Furthermore, sake lees hydrolysate induced the expression of these proteins in HepG2. These results suggested that sake lees hydrolysate could induces HO-1 and γ-GCS expression via activation of the Nrf2 antioxidant pathway, and protects against acetaminophen-induced hepatotoxicity in mice.

Hepatoprotective effects of rice-derived peptides against acetaminophen-induced damage in mice

Glutathione, the most abundant intracellular antioxidant, protects cells against reactive oxygen species induced oxidative stress and regulates intracellular redox status. We found that rice peptides increased intracellular glutathione levels in human hepatoblastoma HepG2 cells. Acetaminophen is a commonly used analgesic. However, an overdose of acetaminophen causes severe hepatotoxicity via depletion of hepatic glutathione. Here, we investigated the protective effects of rice peptides on acetaminophen-induced hepatotoxicity in mice. ICR mice were orally administered rice peptides (0, 100 or 500 mg/kg) for seven days, followed by the induction of hepatotoxicity via intraperitoneal injection of acetaminophen (700 mg/kg). Pretreatment with rice peptides significantly prevented increases in serum alanine aminotransferase, aspartate aminotransferase, and lactate dehydrogenase levels and protected against hepatic glutathione depletion. The expression of γ-glutamylcysteine synthetase, a key regulatory enzyme in the synthesis of glutathione, was decreased by treatment with acetaminophen, albeit rice peptides treatment recovered its expression compared to that achieved treatment with acetaminophen. In addition, histopathological evaluation of the livers also revealed that rice peptides prevented acetaminophen-induced centrilobular necrosis. These results suggest that rice peptides increased intracellular glutathione levels and could protect against acetaminophen-induced hepatotoxicity in mice.

[Gender equality activity in the Bioimaging Society]

Gender equality activity in the Bioimaging Society was initiated in 2005 when it joined the Japan Inter-Society Liaison Association Committee for Promoting Equal Participation of Men and Women in Science and Engineering (EPMEWSE). The Gender Equality Committee of the Bioimaging Society is acting on this issue by following the policy of the EPMEWSE, and has also been planning and conducting lectures at annual meetings of the society to gain the understanding, consents, and cooperation of the members of the society to become conscious of gender equality. Women's participation in the society has been promoted through the activities of the Gender Equality Committee, and the number of women officers in the society has since increased from two women out of 40 members in 2005 to five out of 44 in 2013. The activities of the Gender Equality Committee of the Japanese Association of Anatomists (JAA) have just started. There are more than 400 women belonging to the JAA. When these women members join together and collaborate, women's participation in the JAA will increase.

Characterization of proteins secreted from a type III secretion system of Edwardsiella tarda and their roles in macrophage infection

The Type III secretion system is essential for intracellular replication of Edwardsiella tarda in phagocytes of fish and mammals. We identified the secreted proteins of the Type III secretion system by comparing the wild-type strain and the Type III mutant mET1229. The wild-type strain secreted 55, 25, and 22 kDa proteins into the culture supernatant, whereas the Type III mutant did not. These proteins were identified as EseB, EseC, and EseD and are similar in sequence to Salmonella SseB, SseC, and SseD that function as a translocon. The EseB, EseC, and EseD knockout mutants did not replicate in murine macrophages, suggesting that these proteins are essential for intracellular replication of E. tarda. Highest secretion of EseBCD proteins was observed when bacterial cells were cultured in neutral and alkaline pHs but not in acidic pH. When the pH of the phagosomes was examined using an acidotropic probe, the phagosomes containing the wild-type strain showed neutral pH, whereas those containing the Type III mutant exhibited acidic pH. These results suggest that the Type III-dependent interference with formation of the acidic environment in phagosomes is essential for intracellular replication of bacteria in murine macrophages.

Visualization and dynamic size evaluation of nanoparticles in solution by single optical fiber-illuminated video microscope analysis

AIM

It is hoped that nanoparticles will become ever more useful in the development of nanomedicine. To evaluate the behavior of nanoparticles in solution, we aimed to establish a single optical fiber-illumination method that is easy to integrate with a conventional microscope at low cost.

METHODS

Solutions of gold nanoparticles and carbon nanotubes were analyzed in a single optical fiber-illuminated video microscope and the tracks of Brownian motion of these nanoparticles were traced using video images. Their diffusion coefficient was measured by the mean square displacement of the movement. Using the diffusion coefficient in the Stokes-Einstein equation, the hydrodynamic diameter of the nanoparticles in solution was evaluated.

RESULTS

The visualization of gold nanoparticles clearly in a high signal-to-noise ratio was achieved. The evaluated particle sizes of gold nanoparticles were similar to those obtained by a transmission electron microscope and the aggregation process of the carbon nanotubes following incubation was also observed and similar size estimation of the aggregates was performed.

CONCLUSION

The single fiber-illumination method was applicable to visualize nanoparticle movement clearly and to estimate their sizes in solution. This simple method is suitable for the in situ observation of the nanoparticle-binding process to target cells.

gamma-Tubulin-like molecules in the mouse duodenal epithelium

A mouse monoclonal antibody (G9, Horio et al. in Cell Motil Cytoskel 44:284-295, 1999) that was raised against the gamma-tubulin from a fission yeast, Schizosaccharomyces pombe, showed a unique staining in the mouse small intestine. Similar to another anti-gamma-tubulin antibody that is commercially available, G9 showed typical dot-like staining corresponding to the microtubule-organizing center in the free cells of the epithelium and the connective tissue under it. In addition, G9 stained the cell-cell contacts in the epithelium. This stained region was not bicellular but tricellular junctions of the enterocytes. This staining was unique to G9 and was diminished on the sample of the mouse small intestine, which had lost most of its filamentous microtubules through the preparation process. The tricellular junction is thought to be the weakest point of the epithelial barrier, and no other junctional structures have been identified except for the central sealing elements extending from the tight junctions between the two cells. Our results suggest the existence of a new molecule underlying the tricellular junctions, which may relate to gamma-tubulin and the microtubules.

The Hoshino wooden skeleton, the first wooden model of a human skeleton, made during the Edo era in Japan

The wooden model of the human skeleton, called the wooden skeleton, is a distinguished original craft object from the Edo era, in Japan, when medical doctors were unable to keep a human skeleton for study and teaching purposes. There are three types of wooden skeletons: (i) Hoshino made in 1792; (ii) Kagami made by 1810; and (iii) Okuda made around 1820. The former two are of adult males and the latter is of a female. The wooden skeletons were made with surprising accuracy compared with figures that appeared in the medical books available in Japan at that time, which suggests a scientific readiness of the doctors and the skill of the craftsmen. In the cases of the Hoshino and Kagami wooden skeletons, it is hard to consider that all wooden bones were assembled to show the entire body. Conversely, the Okuda wooden skeletons were made for showing in the sitting position. The skull of the Hoshino wooden skeleton is of special interest: the skull cap was not cut, yet the internal structures of the skull, such as the sella turcica, foramina for nerves and vessels, and the sulci for venous sinuses, were made with considerable accuracy. The skull caps of the Kagami and Okuda wooden skeletons were cut, as those used in modern medical education.

[Wooden models of human skeleton made in Edo era, Japan, with special reference to Hoshino wooden skeleton]

The wooden model of the human skeleton, called wooden skeleton, is a distinguished original craft object in Edo era (1600-1867), Japan, when medical doctors were unable to keep the human skeleton for their study and teaching purpose. There are three kinds of wooden skeletons, i. e. Hoshino, Kagami and Okuda wooden skeletons made in 1792, 1810 and 1820, respectively. The former two are of adult male and the latter of female. They were made in surprising accuracy as compared with figures appeared in medical books available in Japan at that time, which suggests scientific readiness of the doctors and skills of the craftsmen. A complete set of the skeleton, except for the hyoid bone, has been preserved for Hoshino and Okuda wooden skeletons, while several bones have been missing in Kagami wooden skeleton. Each bone of Hoshino and Kagami wooden skeletons was made separately and connected by a tenon and a corresponding mortise at the articular surface. So it is hardly considered that all wooden bones were assembled into the whole body skeleton on use. Okuda wooden skeleton, on the other hand, was made for being shown in sitting position. The skull of Hoshino wooden skeleton is of special interest: the skull cap is not open, yet the internal structures of the skull, such as the sella turcica, foramina for nerves and vessels, and sulci for venous sinuses were made in considerable accuracy. Moreover, the proper connection of most foramina was proved between the inside and outside of the skull. The skull caps of Kagami and Okuda wooden skeletons are open as those used in the modern medical education.

[Anatomy education in medical and dental schools in Japan]

We studied the anatomy education and the view of anatomy professors on it in medical and dental schools in Japan. In most schools anatomy is taught in the second year. In medical schools, the systematic education separating macroscopic and microscopic anatomy is prevalent. Although the tutorial system has been introduced in 80% of medical schools, its introduction into anatomy education has remained at 30%. The tutorial system is regarded to be more effective by engaged professors than non-engaged. Some kinds of clinical anatomy education have been introduced in half of the medical schools surveyed. In dental schools, on the other hand, macroscopic and microscopic anatomy tend to be taught in combination. One third of the dental schools have introduced clinical anatomy but few schools have a tutorial system. The overwhelming majority of professors are evaluated by students and have regarded the evaluation useful for improving their teaching. They also have thought that the questionnaire and the timing of the evaluation must be considered carefully, and that the evaluation should not be directly used for purposes other than the improvement of education. We have made the proposals for further improvement in anatomy education based upon this study.

Human coronavirus 229E binds to CD13 in rafts and enters the cell through caveolae

CD13, a receptor for human coronavirus 229E (HCoV-229E), was identified as a major component of the Triton X-100-resistant membrane microdomain in human fibroblasts. The incubation of living fibroblasts with an anti-CD13 antibody on ice gave punctate labeling that was evenly distributed on the cell surface, but raising the temperature to 37 degrees C before fixation caused aggregation of the labeling. The aggregated labeling of CD13 colocalized with caveolin-1 in most cells. The HCoV-229E virus particle showed a binding and redistribution pattern that was similar to that caused by the anti-CD13 antibody: the virus bound to the cell evenly when incubated on ice but became colocalized with caveolin-1 at 37 degrees C; importantly, the virus also caused sequestration of CD13 to the caveolin-1-positive area. Electron microscopy confirmed that HCoV-229E was localized near or at the orifice of caveolae after incubation at 37 degrees C. The depletion of plasmalemmal cholesterol with methyl beta-cyclodextrin significantly reduced the HCoV-229E redistribution and subsequent infection. A caveolin-1 knockdown by RNA interference also reduced the HCoV-229E infection considerably. The results indicate that HCoV-229E first binds to CD13 in the Triton X-100-resistant microdomain, then clusters CD13 by cross-linking, and thereby reaches the caveolar region before entering cells.

Use of taxol and collagenase for better three-dimensional visualization of microtubules in the enterocyte and Brunner's gland cell, with special reference to their relation to the Golgi apparatus

Cytoskeletal microtubules were visualized in the mouse duodenal mucosa by an improved immunofluorescence method using a microtubule-stabilizing reagent, Taxol, and collagenase as an enzymatic epitope retriever. The improvement in immunostaining was shown morphologically and statistically by comparing fluorescence intensities of specimens prepared with or without Taxol and collagenase treatment. In free cells in the epithelium and in the lamina propria, microtubules radiated from the gamma-tubulin-immunostained organizing center. Enterocytes and Brunner's gland cells double-stained with an anti-alpha-tubulin antibody and a lectin (Helix pomatia agglutinin, soybean agglutinin or Ulex europaeus agglutinin-I) showed that microtubules ran along the cell axis and were abundant between the Golgi apparatus and the apical surface. The microtubules appeared to provide a structural support to hold the Golgi apparatus in position and to act as railways for secretory granules, which are transported towards the apical surface. In addition, gamma-tubulin-like immunoreactivity was associated with the Golgi apparatus in the enterocytes. These results show that the method using Taxol and collagenase is effective for visualizing microtubules in epithelial cells, and that microtubules may play important roles in both positioning of the Golgi apparatus and transport of secretory granules. Our results also support the idea that the Golgi apparatus may act as an organizing center for microtubules.

Gliding movement in Peranema trichophorum is powered by flagellar surface motility

A colorless euglenoid flagellate Peranema trichophorum shows unique unidirectional gliding cell locomotion on the substratum at velocities up to 30 micro m/s by an as yet unexplained mechanism. In this study, we found that (1) treatment with NiCl(2) inhibited flagellar beating without any effect on gliding movement; (2) water currents applied to a gliding cell from opposite sides caused detachment of the cell body from the substratum. With only the anterior flagellum adhering to the substratum, gliding movement continued along the direction of the anterior flagellum; (3) gentle pipetting induced flagellar severance into various lengths. In these cells, gliding velocity was proportional to the flagellar length; and (4) Polystyrene beads were translocated along the surface of the anterior flagellum. All of these results indicate that a cell surface motility system is present on the anterior flagellum, which is responsible for cell gliding in P. trichophorum.

Immunofluorescence detection of gastric H(+)/K(+)-ATPase and its alterations as related to acid secretion

Parietal cells in the rat oxyntic mucosa were analyzed by the immunofluorescence pattern of the proton pump. The adult rats were grouped into fasting (C), gastrin-treated (G), and ranitidine-treated (R) groups, gastric pH was measured, and the stomach was processed for immunohistochemistry. The fluorescence of parietal cells showed a reticular, diffuse, or mixed pattern in cytoplasm. Quantitatively, 53% of the total cells showed the reticular pattern in group G (pH 1.9), 44% in group C (pH 2.0), and 0% in group R (pH 6.7). On the other hand, 7.0% of the total cells showed the diffuse pattern in group G, 11.9% in group C, and 56.2% in group R. The results indicated that the staining pattern depended on the activity of acid secretion. In addition, the proportion of parietal cells showing the reticular pattern decreased in the following order, the superficial, middle, and deep third of the mucosa, and the diffuse pattern showed the opposite trend. This suggests that the acid secretion is more active in parietal cells in the superficial part of the mucosa. The double staining with proton pump-specific and cytochrome oxidase-specific antibodies revealed the close relation between reticular fluorescence and mitochondria.

The Golgi apparatus of goblet cells in the mouse descending colon: three-dimensional visualization using a confocal laser scanning microscope

The three-dimensional structure of the Golgi apparatus was studied in goblet cells in lectin-stained sections of the mouse descending colon by using a confocal laser scanning microscope. In the lower part of the crypt, the Golgi apparatus formed a dome- or globe-like structure in the supranuclear region. The wall of the dome had some holes, one of which usually faced toward the nucleus and others toward the apical cytoplasm. Mucous granules seemed to be initially released into the interior of the dome and transported toward the apical cytoplasm through the holes. In the upper part of the crypt, on the other hand, the Golgi apparatus formed a cup- or funnel-like structure with a larger opening toward the cell apex and a smaller opening toward the nucleus. A large mass of mucous granules occupied the inside of the cup to the apical cytoplasm. It is thought that the accumulation of mucous granules enlarges holes at the ceiling of the dome to form a large opening, which makes the configuration of the Golgi apparatus cup-shaped.

Video-rate dynamics of exocytotic events associated with phagocytosis in neutrophils

Exocytotic responses associated with phagocytosis were investigated in a single neutrophil with a special reference to their dynamic properties and their spatiotemporal relationships with ionic and chemical responses during phagocytosis. The real-time sequence of phagocytosis-exocytosis was directly visualized by video-enhanced contrast differential interference contrast (VEC-DIC) microscopy. The actual release of contents from such a granule was proven by examining a cell loaded with quinacrine with a dual imaging system that allowed us to observe DIC and fluorescence images simultaneously at a high magnification. During the process of phagosome formation in a neutrophil engulfing an opsonized zymosan, the exocytotic response was observed first in a granule located near the cell surface initially attached to the zymosan, and then in other granules sequentially along pseudopodia surrounding the zymosan. When the phagocytosis was induced in a medium containing luminol, a chemiluminescence due to active oxidants was detected exclusively in the region of phagosome, suggesting that exocytosis took place on the phagosomal membrane and not on the plasma membrane. Changes in cytosolic free calcium concentration ([Ca2+]i) were further measured using fura-2 under the dual imaging system. [Ca2+]i transients were more closely related to the extension of pseudopodia for engulfing zymosan and not directly to the exocytosis. These findings lead to a conclusion that exocytosis associated with phagocytosis is initiated by attachment of the cell membrane to the invading organism and mediated by local activation of the phagosomal membrane.

Three-dimensional visualization of the Golgi apparatus: observation of Brunner's gland cells by a confocal laser scanning microscope

The three-dimensional structure of the Golgi apparatus in cells of the Brunner's gland in the mouse was observed by using a confocal laser scanning microscope. Two lectins, FITC-labeled soybean agglutinin and Texas red-labeled Griffonia simplicifolia agglutinin II, were used to visualize the whole Golgi apparatus. Staining with the former lectin, which has been known to label the cis-stacks, showed a lacy dome-like structure situated in the supranuclear region. Staining with the latter lectin, known to label the intermediate-to-trans-stacks and the secretory granules, showed a dome-like structure consisting of network and cobblestone-like patterns in the same region and also granular stainings near the surface of the cobblestone-like patterns and the apical region of a cell. Double-staining demonstrated that the soybean agglutinin-labeled network always surrounded the G. simplicifolia agglutinin II-stained structure. Based on these observations, we propose a new three-dimensional model of the Golgi apparatus: it forms a dome-like structure over a nucleus, a network of cis-stacks forms its outer boundary, and this outer boundary is lined and paved with successive intermediate and trans-stacks. It is thought that secretory granules are released toward the internal space of the Golgi apparatus and transported to the apical cytoplasm through the holes of the network.

Video-rate dynamics of exocytotic events associated with phagocytosis in neutrophils

Exocytotic responses associated with phagocytosis were investigated in a single neutrophil with a special reference to their dynamic properties and their spatiotemporal relationships with ionic and chemical responses during phagocytosis. The real-time sequence of phagocytosis-exocytosis was directly visualized by video-enhanced contrast differential interference contrast (VEC-DIC) microscopy. The actual release of contents from such a granule was proven by examining a cell loaded with quinacrine with a dual imaging system that allowed us to observe DIC and fluorescence images simultaneously at a high magnification. During the process of phagosome formation in a neutrophil engulfing an opsonized zymosan, the exocytotic response was observed first in a granule located near the cell surface initially attached to the zymosan, and then in other granules sequentially along pseudopodia surrounding the zymosan. When the phagocytosis was induced in a medium containing luminol, a chemiluminescence due to active oxidants was detected exclusively in the region of phagosome, suggesting that exocytosis took place on the phagosomal membrane and not on the plasma membrane. Changes in cytosolic free calcium concentration ([Ca2+]i) were further measured using fura-2 under the dual imaging system. [Ca2+]i transients were more closely related to the extension of pseudopodia for engulfing zymosan and not directly to the exocytosis. These findings lead to a conclusion that exocytosis associated with phagocytosis is initiated by attachment of the cell membrane to the invading organism and mediated by local activation of the phagosomal membrane.

Quantitative analysis of exocytosis visualized by a video-enhanced light/fluorescence microscope reveals two distinct components of exocytosis in RBL-2H3 cells

Rat basophilic leukemia (RBL-2H3) cells, which exhibit Ca2+-dependent secretion of granules when stimulated with antigen or the Ca2+-ionophore A23187, were observed under a video-enhanced light/fluorescence microscope. Exocytotic events of individual granules were visualized in individual cells stimulated with antigen or A23187. Exocytosis of granules stimulated with A23187 showed two peaks in the time course. The earlier one was inhibited by selective inhibitors of protein kinase C (Ro31-8425, Ro31-8220, and chelerythrine) and the other was inhibited by an inhibitor of phosphatidate hydrolase, propranolol. Exocytosis by antigen stimulation, however, showed only one peak, which was inhibited by the selective inhibitors of protein kinase C, but not by propranolol. These results indicate that at least two distinct components of exocytosis exist in RBL-2H3 cells.

Quantitative analysis of superoxide anion generation in living cells by using chemiluminescence video microscopy

Superoxide anions (O2-) generated by rabbit neutrophils were detected and quantified by a video microscope equipped with a photon-counting camera. One count obtained by this system was equivalent to 59 amol of O2-. Maximum O2- production was observed at 6-8 min after stimulation and was estimated as 1.9 fmol/min per cell on the average.

A histochemical study on glycoconjugates in epithelial cells in the distal colonic mucosa of adult and developing mice

Glycoconjugates were histochemically studied in the distal colon of developing ICR mice in view of the presence of goblet and vacuolated cells. Alcian blue, high iron diamine and periodic acid-Schiff stainings were performed to characterize glycoconjugates. In addition, two lectins, Ulex europeus agglutinin I and Limax flavus agglutinin, were applied to detect fucosyl and sialyl residues, respectively. The reactivities to these stainings, noted from day 18 of gestation, did not seem to undergo any major change throughout their development. The present results suggest that: 1) goblet cells secrete sulfated glycoconjugates containing fucosyl and sialyl residues as terminal sugars; 2) vacuolated cells have glycoconjugates containing sialyl residues but no or few fucosyl residues nor sulfonic groups, and certain sialyl residues in the glycoconjugates are probably O-acetylated or O-acylated at least in part; and 3) the brush border of absorptive cells contains glycoconjugates sialylated and fucosylated to same extent but rarely sulfated. Since glycoconjugates elaborated by goblet and vacuolated cells differ from each other, one should be fully aware of the presence of these two types of mucin-producing cells in the distal colon.

[Development of multicomponent immunoassay and micro-localization analysis by laser-photoacoustic and microscopic image analyzer]

Laser photoacoustic spectroscopy (PAS) has a potential to be developed as a sensitive and solid-phase analytical method and was applied to enzyme immunoassay. The test sample for immunoassay was prepared by adsorbing multi-component immunoglobulins on a nitrocellulose membrane filter. Human lambda- and kappa-chains, which are used as a principal indication of malignant lymphoreticular disease, and immunoglobulin G were used as model proteins, and PAS immunoassay was applied to the individual detection of these three proteins in the urine. Furthermore, in order to develop a sensitive analysis for particular biological components in tissues or cells, laser photoacoustic microscopy (PAM) and video intensified microscopy (VIM) were developed. PAM was shown to be applicable to the detection and quantification of human lambda-chain in a micro-region of the tissue sections of the human fetal spleen and pancreas. VIM was applied to the detection of stimulation-response processes in a cell. By using neutrophils which are stimulated by many substances and produce active oxidants as the results, dynamic changes in the stimulation-response process in a living cell were visualized as fluorescence or chemiluminescence images by the VIM system.

Lectin cytochemistry in the gastrointestinal tract with special reference to glycosylation in the Golgi apparatus of Brunner's gland cells

Two hydrophilic, low temperature-embedding resins, Lowicryl K4M and LR White, were compared in lectin cytochemistry. Post-embedding staining of colloidal gold-labeled Griffonia symplicifolia agglutinin II (GSA-II) resulted in staining of the Golgi apparatus and mucous granules of mucous neck cells in the gastric fundic gland, pylorocytes, and Brunner's gland cells embedded in either resin, although it was much easier to make ultra-thin sections with LR White-embedded material than with the other. Post-fixation with uranyl acetate followed by LR White embedding improved general ultrastructure so that lectin binding sites were identified precisely. All examined lectins, soybean agglutinin (SBA), Maclura pomifera agglutinin (MPA), GSA-II, and Ulex europaeus agglutinin I (UEA-I), stained mucous granules and the Golgi apparatus, in which the staining pattern was characteristic of each lectin: cis cisternae were labeled with SBA and MPA, intermediate cisternae with GSA-II, and trans cisternae and mucous granules with SBA, GSA-II, UEA-I, and lightly with MPA. No labeling was observed in the rough endoplasmic reticulum with any lectin. These findings suggest that the Golgi apparatus is the site of O-linked glycosylation and can be divided into at least three distinct compartments with regard to the glycosylation.

Glycoconjugates on the surface of spores of the pathogenic fungus Phytophthora cinnamomi studied using fluorescence and electron microscopy and flow cytometry

Glycoconjugates on the surface of zoospores and cysts of the pathogenic fungus Phytophthora cinnamomi have been studied using fluorescein isothiocyanate labelled lectins for fluorescence microscopy and flow cytometry, and ferritin- and gold-labelled lectins for ultrastructural analysis. Of the five lectins used, only concanavalin A (ConA) binds to the surface of the zoospores, including the flagella and water expulsion vacuole. This suggests that of accessible saccharides, glucosyl or mannosyl residues predominate on the outer surface of the zoospore plasma membrane. Early in encystment, a system of flat disc-like cisternae, which underlie the zoospore plasma membrane, vesiculate. These and other small peripheral vesicles quickly disappear. After the induction of encystment, ConA is no longer localised close to the plasma membrane but binds to material loosely associated with the cell surface. Quantitative measurements by flow cytometry indicate that the ConA-binding material is gradually lost from the cell surface. The cyst wall is weakly labelled, but the site of germ tube emergence stains intensely. During the first 2 min after the induction of encystment, material that binds soybean agglutinin, Helix pommatia agglutinin, and peanut agglutinin appears on the surface of the fungal cells. The distribution of this material, rich in galactosyl or N-acetyl-D-galactosaminosyl residues, is initially patchy, but by 5 min the material evenly coats most of the cell surface. Labelling of zoospores in which intracellular sites are accessible indicates that the soybean agglutinin binding material is stored in vesicles that lie beneath the plasma membrane. Quantitation of soybean agglutinin labelling shows that maximum binding occurs 2–3 min after the induction of encystment. Key words: cell surface, flow cytometry, lectins, pathogenic fungi, Phytophthora cinnamomi.

Stimulative effect of chlordane on the various functions of the guinea pig leukocytes

The effects of the chlordane-related compounds, cis-chlordane, trans-chlordane, heptachlor, and heptachlor epoxide, on stimulation responses of guinea pig polymorphonuclear leukocytes (PMNs) were examined. Treatment of PMN with these compounds stimulated superoxide (O2-) generation, altered membrane potential, and increased intracellular Ca2+ concentration ([Ca2+]i). However, there was no definite tendency among the stimulating effects of chlordane-related compounds, therefore the relationship between the effect and molecular structure of these substances remains unknown. Of these response reactions of PMN stimulated by chlordane-related compounds, stimulation of O2- generation lagged behind others. Increase in [Ca2+]i was due both to acceleration of extracellular Ca2+ penetration and to Ca2+ release from the intracellular pool. These results indicate that chlordane-related compounds stimulate PMN and suggest a causal relationship between the stimulation of O2- generation by these substances and their toxicity.

Inhibitory effect of cholesterol on interaction between cytoplasmic actin and liposomes, and restorative effect of high osmotic pressure

Although cholesterol is one of the major components of plasma membranes in eukaryotic cells, very little is known about its role in biological membranes. We reported previously (Okimasu et al., Cell Struct. Funct. 11, 273-283, 1986) that introduction of cholesterol into the liposomal membrane caused a decrease in membrane permeability, especially by the binding of cytoplasmic proteins to the liposomal membrane. The present study was carried out to further clarify the biochemical function of cholesterol in the membrane-protein interactions, especially under high osmotic pressure. The association of membranes with cytoplasmic proteins and their permeability were decreased by the introduction of cholesterol, but its effects were diminished in a hypertonic medium. The protein species associated with cholesterol-containing liposomes vary depending on the sort of hypertonic condition. It was suggested that since the degree of lipid packing by the cholesterol was reduced by the locally increased curvature in the lipid bilayer under high osmotic pressure, some cytoplasmic proteins can penetrate into the liposomal membrane.

Monoclonal antibodies to isolate-, species-, and genus-specific components on the surface of zoospores and cysts of the fungus Phytophthora cinnamomi

Monoclonal antibodies have been raised to components on the surface of glutaraldehyde-fixed zoospores and cysts of an isolate of the pathogenic fungus Phytophthora cinnamomi. Hybridoma supernatants were screened using an immunofluorescence assay, and of 35 cell lines producing antibodies that reacted with the P. cinnamomi cells, 10 have been selected and their specificities examined in detail. The monoclonal antibodies were found to possess a valuable spectrum of taxonomic specificities, and have revealed, for the first time, the presence of isolate-specific antigens on the surface of P. cinnamomi cells. The monoclonal antibodies were tested against six isolates of P. cinnamomi, six species of Phytophthora, and three species of Pythium. In addition to the isolate-specific monoclonal antibodies, species-specific and genus-specific markers which are unambiguous in tests conducted so far have been obtained. The monoclonal antibodies have also revealed the presence of spatially restricted antigens on the surface of the zoospores. Some of these segregated antigens are species-specific and others are more general, occurring in all Phytophthora and Pythium species examined. All of the monoclonal antibodies promise to be of great assistance in investigations of the biology and taxonomy of P. cinnamomi. The methods described should be readily applicable to studies of other fungal pathogens.