Ultrastructural study of periodic lamellar granules in human neutrophils

Granules consisting of periodically arranged membranous lamellae and amorphous electron-opaque material, i.e., periodic lamellar granules, are present in human neutrophils. To date, no extensive ultrastructural studies have been carried out on these granules because of their infrequent presence in neutrophils. The bone marrow of 18 cases of chronic myeloproliferative disorders, including one case of chronic neutrophilic leukemia in which periodic lamellar granules were frequently seen in neutrophils, was investigated by electron microscopy. Periodic lamellar granules were seen in neutrophils in 12 of the 18 cases at varying frequencies. They were preferentially seen in immature neutrophils. The transverse profiles of these granules revealed concentric complete/incomplete rings or periodic parallel straight lines, i.e., various patterns of lamellar arrangement were present. Periodic lamellar granules were positive for myeloperoxidase and lysozyme at the electron-microscopic level. These results suggest that these granules represent a primary neutrophil granule subtype. However, their functional and pathologic significance remains unknown.

Detection and quantification of virus DNA in plasma of patients with Epstein-Barr virus-associated diseases

Epstein-Barr virus (EBV) causes various diseases, such as infectious mononucleosis (IM), fatal IM, EBV-associated hemophagocytic syndrome (EBVAHS), and chronic active EBV infection (CAEBV). In the present study, cell-free EBV DNA was detected in the plasma of patients with EBV-associated diseases by PCR assay. The patients included 20 patients with IM, 2 patients with fatal IM, 4 patients with EBVAHS, 4 patients with CAEBV, and 38 healthy children (20 EBV seropositive and 18 EBV seronegative). In patients with IM, plasma samples were positive for EBV DNA in all patients (100%) in the acute phase and in 44% of the patients in the convalescent phase, but plasma samples from the 38 healthy control children were negative (0%) for EBV DNA. Quantitative PCR assay revealed that plasma from patients with IM contained the highest amount of virus DNA within 7 days following the onset of disease (mean, 6 x 10(4) copies per ml). The EBV DNA concentration decreased thereafter as the patients recovered. Plasma from patients with fatal IM contained more than 100 times more copies of EBV DNA (3 x 10(7) copies per ml) than plasma from patients with IM. Plasma from patients with the acute phase of EBVAHS contained 10 times more copies of EBV DNA (5 x 10(5) copies per ml) than plasma from IM, and then patients with the number of copies decreased similarly in both groups of patients in the convalescent phase (2 x 10(4) copies per ml). The amount of virus DNA in patients with CAEBV (6 x 10(4) copies per ml) was similar to that noted in patients with IM; however, it became higher (1 x 10(6) copies per ml) when the patients' clinical status deteriorated. These data suggest that the presence of cell-free EBV DNA in plasma is a common phenomenon in patients with EBV-associated diseases. The concentration of EBV DNA in plasma seems to be higher in patients with the more severe clinical categories of EBV diseases.

Effects of sevoflurane on the middle latency auditory evoked response and the electroencephalographic power spectrum

We investigated the effects of sevoflurane on the middle latency auditory evoked response (MLR) and the power spectrum of the electroencephalogram (EEG) in 10 elective surgical patients. The MLR and the EEG power spectrum were recorded with a surface electrode placed at the central (Cz) scalp location. End-tidal sevoflurane concentrations of 0%, 0.25%, 0.5%, 0.75%, 1.0%, and 1.5% in 50% nitrous oxide and oxygen were studied. The Na, Pa, and Nb components of the MLR increased in latency and decreased in amplitude in a dose-dependent manner at increasing concentrations of sevoflurane. The latencies for Na, Pa, and Nb increased in a linear fashion (correlation coefficients: r = 0.81, r = 0.81, and r = 0.89, respectively). The EEG delta power was dominant with increasing sevoflurane concentration, and was significantly increased at sevoflurane concentrations of 1.0%-1.5%. The beta power, median power frequency (MPF), and 95% spectral edge frequency (SEF) decreased significantly according to the increases by 0.5% sevoflurane. Regarding the changes evoked by 0.25% sevoflurane, the Nb latency of the MLR responded significantly under 0.75% of sevoflurane. At these low concentrations of sevoflurane, the MLR seemed to be more sensitive to changes in anesthetic concentration than the various EEG variables.

Sequencing and the alignment of structural genes in the nqr operon encoding the Na(+)-translocating NADH-quinone reductase from Vibrio alginolyticus

We previously cloned a part of nqr operon encoding the Na(+)-translocating NADH-quinone reductase (NQR) from the marine Vibrio alginolyticus [Hayashi et al., FEBS Lett. 356 (1994) 330-332]. From its nucleotide sequences, four consecutive open reading frames (ORF) encoding the gamma-subunit (27.7 kDa), two unidentified ORFs of 22.6 kDa and 21.5 kDa, and the beta-subunit (45.3 kDa) were recognized. The gene encoding the alpha-subunit was located upstream, and together with the recent report by Beattie et al. [FEBS Lett. 356 (1994) 333-338], the nqr operon was found to be constructed from six consecutive structural genes, where nqr1, nqr3 and nqr6 correspond to the alpha-, gamma-, and beta-subunits, respectively, of the NQR complex.

Light and electron microscope study of splenoportal milky spots in New Zealand black mice: comparison between splenoportal milky spots and aberrant spleens

The omentum contains peculiar lymphoid tissues termed omental milky spots. In mice, similar milky spots (splenoportal milky spots) are present in splenoportal fat bands developing along the splenic artery. We found that New Zealand Black (NZB) mice, which are known to develop spontaneous autoimmune diseases, have well developed splenoportal milky spots. However, little is known about these milky spots. Thus we investigated splenoportal fat bands in NZB mice by light and electron microscopy. Splenoportal fat bands contained sporadic aberrant spleens as well as abundant milky spots. In addition, transitional forms between splenoportal milky spots and aberrant spleens, although sporadic, were present in the fat bands. Splenoportal milky spots were supplied with offshoots from the splenic artery and were composed of abundant lymphocytes with macrophages, plasma cells, granulocytes, megakaryocytes and various stromal cells. In addition, they showed active neutrophilic myelopoiesis and probable megakaryopoiesis. Aberrant spleens were also supplied by branches from the splenic artery. They showed active granulopoiesis, megakaryopoiesis, and erythropoiesis. The transitional forms resembled splenoportal milky spots in structure, but the former showed extramedullary haematopoiesis of three cell lineages. The morphological transition from aberrant spleens, via transitional forms, to splenoportal milky spots seems to indicate that splenoportal milky spots represent splenoid lymphoid tissues.

Pharmacological study of stem-cell-factor-induced mast cell histamine release with kinase inhibitors

Stem cell factor (SCF) is a ligand for c-kit receptor and has a critical role in the development of mast cells. In this study, we investigated the effect of a panel of kinase inhibitors on SCF-induced histamine release from rat peritoneal mast cells. Genistein, an inhibitor of tyrosine kinases, inhibited SCF-induced histamine release with IC50 of 1.6 x 10(-5) M. Wortmannin, an inhibitor of phosphatidylinositol 3'-kinase (PI3 kinase), inhibited histamine release stimulated with SCF dose-dependently with IC50 of 4 x 10(-9) M. KT5926, an inhibitor of myosin light chain (MLC) kinase, reduced histamine release with IC50 of 1.8 x 10(-7) M. Staurosporine, an inhibitor of protein kinases, also inhibited SCF-induced histamine release with IC50 of 6.5 x 10(-8) M. These results show the early involvement of tyrosine kinase and PI3 kinase and the possible role of MLC kinase in the late secretory phase in the signaling pathway used by SCF.

Nucleotide sequence of a highly repeated DNA sequence and its chromosomal localization in Allium fistulosum

A highly repeated DNA sequence with a repeating unit of approximately 380bp was found in EcoRV digests of the total genomic DNA of Allium fistulosum. Three independent clones containing this unit were isolated, and their repeating units sequenced. These units showed more than 94% sequence homology, and the copy number was estimated to be about 2.8×10(6) per haploid genome. In situ hybridization, with the repeating unit as a probe, and C-banding analyses indicated that the repeated DNA sequence of A. fistulosum is closely associated with the major C-heterochromatin in the terminal regions of all 16 chromosomes at mitotic metaphase. The characters of the repeating unit are similar to those of the A. cepa unit, which is taxonomically closely related to A. fistulosum.

An ultrastructural study of primary granule subtypes in human neutrophils

To investigate the heterogeneity of primary neutrophil granules, neutrophils in the bone marrow of 68 patients with hematologic and non-hematologic diseases were observed by electron microscopy. In addition to typical primary granules, 3 primary granule subtypes, i.e., parallel tubular granules (PTGs), fibrillar granules (FGs), and periodic lamellar granules (PLGs), were present in neutrophils. PTGs were found in only one case of chronic neutrophilic leukemia (CNL). On the other hand, FGs and PLGs were present in various cases at varying frequencies. Three subtype granules were seen preferentially in immature neutrophils. These subtypes were positive for myeloperoxidase, showing that they represent primary granules. In addition, hybrid PTG/FG granules, hybrid PTG/PLG granules, and hybrid FG/PLG granules were seen in the PTG-positive CNL case. This shows that a close association is present between PTGs, FGs, and PLGs.

nfxC-type quinolone resistance in a clinical isolate of Pseudomonas aeruginosa

Quinolone resistance gene nqr-T91 in a clinical isolate of Pseudomonas aeruginosa P1481 was cotransducible with catA1 in P. aeruginosa PAO. The nqr-T91 transductant, PKH-T91, was resistant to norfloxacin, imipenem, and chloramphenicol and showed less norfloxacin accumulation than the parent strain did. Loss of the 46-kDa outer membrane protein (D2) and an increase in the 50-kDa outer membrane protein in PKH-T91 were observed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Lipopolysaccharides in the transductant were also changed. These alterations were considered to be related to lower levels of norfloxacin accumulation in PKH-T91. These genetic and biochemical properties suggested that an nfxC type of quinolone-resistant mutation occurred in a clinical isolate of P. aeruginosa P1481.

Effects of an indene-derivative, TN-871, on synaptic transmission in a sympathetic ganglion: presynaptic actions on neurotransmitter release

Intracellular recordings were made from bullfrog sympathetic ganglion cells to elucidate effects of 2-n-butyl-1-(4-methylpiperazinyl)-5,6-methylenedioxyindene.2 HCl (TN-871) on synaptic transmission. TN-871 at 30 nM augmented cholinergic nicotinic fast excitatory postsynaptic potentials (fast EPSPs), whereas the drug at 3 microM reversibly depressed them, without affecting acetylcholine-induced depolarizations. TN-871 did not affect active and passive electrical properties of the ganglion cells. The quantal analysis method was applied to the fast EPSPs in a 0.54 mM Ca2+/7.56 mM Mg2+ Ringer's solution. The mean quantal content was significantly increased by TN-871 at 30 nM but significantly decreased at 3 microM. TN-871 at 300 nM either increased or decreased the mean quantal content. The mean quantal size of the fast EPSPs was not changed by TN-871 at the concentrations examined. Fast EPSPs in a 0.99 mM Ca2+/4.86 mM Mg2+ Ringer's solution were not affected by nicardipine, but were inhibited in amplitude by omega-conotoxin in a concentration-dependent manner. It is likely that TN-871, in high concentrations, might block omega-conotoxin-sensitive N-type calcium channels in the presynaptic terminals. These results indicate that TN-871 modulates transmitter release from preganglionic nerve terminals without changing the postsynaptic sensitivity of the ganglion cells to ACh.

An infantile case of cytomegalovirus induced idiopathic thrombocytopenic purpura with predominant proliferation of CD10 positive lymphoblast in bone marrow

An infant with cytomegalovirus infection (CMV) developed idiopathic thrombocytopenic purpura (ITP) at 4 months of age. A bone marrow (BM) aspiration showed a remarkable increase of immature megakaryocytes and prominent proliferation of lymphoblasts. Flow cytometric analysis of the bone marrow cells showed that the predominant cells in the lymphocyte cluster were of B-lineage (CD19) with CD10 (common acute lymphoblastic leukemia antigen) positive. Virus study showed a higher titer of CMV antibody. Cytomegalovirus DNA was detected by the polymerase chain reaction (PCR) method in urine, peripheral cells and marrow cells. Low-grade fever, diarrhea and petechiae were accompanied by mild liver dysfunction. Complete remission was made with intravenous high-dose immunoglobulin (IVIg) without progression to overt acute leukemia. The percentage of CD10+/CD19+ lymphocytes in bone marrow also diminished. We postulated that the proliferation of immature lymphocytes and megakaryocytes in bone marrow was caused by maturation arrest that might result from CMV infection.

Chemotactic agonists induce cytokine generation in eosinophils

Recent studies have shown that eosinophils are capable of generating and releasing cytokines, providing a novel biologic aspect of eosinophils for regulating allergic inflammation by an autocrine or paracrine mechanism. Eosinophils synthesize various cytokines; however, the physiologic stimuli that trigger eosinophils to generate cytokines have not been fully elucidated. We examined the effect of chemotactic agonists on eosinophil cytokine generation by employing the determination of IL-8 as the main parameter. Both C5a and FMLP stimulated eosinophils to release IL-8, whereas platelet-activating factor and C-C chemokines did not exert any significant effects. On a molar basis, C5a was two orders of magnitude more potent than FMLP. The generation of IL-8 by chemoattractants was absolutely dependent on the presence of cytochalasin B. Pertussis toxin completely attenuated C5a- and FMLP-induced IL-8 production, indicating the involvement of pertussis toxin-sensitive G-proteins in the signal-transduction process leading to these responses. Experiments of in situ hybridization and PCR amplification revealed that both C5a and FMLP promoted eosinophil IL-8 production through transcriptional gene activation. Pyrrolidine dithiocarbamate completely abrogated chemoattractant-induced IL-8 production, indicating the involvement of NF-kappa B in the cytoplasmic/nuclear signal-transduction process. Furthermore, chemoattractant-induced cytokine production was not limited to IL-8; C5a and FMLP but not platelet-activating factor induced significant secretion of granulocyte-macrophage-CSF from eosinophils. These results indicate that C5a and FMLP stimulate eosinophils to elaborate cytokines, which could be an important mechanism in the regulation of allergic inflammation.

Chemotactic agonists induce cytokine generation in eosinophils

Recent studies have shown that eosinophils are capable of generating and releasing cytokines, providing a novel biologic aspect of eosinophils for regulating allergic inflammation by an autocrine or paracrine mechanism. Eosinophils synthesize various cytokines; however, the physiologic stimuli that trigger eosinophils to generate cytokines have not been fully elucidated. We examined the effect of chemotactic agonists on eosinophil cytokine generation by employing the determination of IL-8 as the main parameter. Both C5a and FMLP stimulated eosinophils to release IL-8, whereas platelet-activating factor and C-C chemokines did not exert any significant effects. On a molar basis, C5a was two orders of magnitude more potent than FMLP. The generation of IL-8 by chemoattractants was absolutely dependent on the presence of cytochalasin B. Pertussis toxin completely attenuated C5a- and FMLP-induced IL-8 production, indicating the involvement of pertussis toxin-sensitive G-proteins in the signal-transduction process leading to these responses. Experiments of in situ hybridization and PCR amplification revealed that both C5a and FMLP promoted eosinophil IL-8 production through transcriptional gene activation. Pyrrolidine dithiocarbamate completely abrogated chemoattractant-induced IL-8 production, indicating the involvement of NF-kappa B in the cytoplasmic/nuclear signal-transduction process. Furthermore, chemoattractant-induced cytokine production was not limited to IL-8; C5a and FMLP but not platelet-activating factor induced significant secretion of granulocyte-macrophage-CSF from eosinophils. These results indicate that C5a and FMLP stimulate eosinophils to elaborate cytokines, which could be an important mechanism in the regulation of allergic inflammation.

Usefulness of omp1 restriction mapping for avian Chlamydia psittaci isolate differentiation

Sixty-five avian Chlamydia psittaci isolates collected worldwide, including 27 previously characterized reference strains, were analysed by restriction mapping of the major outer membrane protein gene (omp1) obtained after DNA amplification by PCR. They were compared to 2 ruminant isolates, a feline pneumonitis and a guinea pig inclusion conjunctivitis (GPIC) isolate. According to their omp1 restriction patterns, avian strains were heterogeneous in that they exhibited 6 and 4 distinct patterns using AluI and MboII restriction enzymes, respectively, thus defining 7 groups. However, 84% of the studied strains belonged to groups 1 to 4, which share a specific fragment triplet of 411, 282 and 102 base pairs in their AluI digestion patterns. Comparisons with serological classifications showed a strict correlation and allowed further intraserovar differentiation. Furthermore, this classification based upon a single gene (omp1) roughly correlated with the data obtained by RFLP of native DNA and DNA/DNA hybridization studies. There was no host or geographic specificity in the pattern exhibited by these strains. The ruminant, feline pneumonitis and GPIC C. psittaci isolates were clearly distinguished from each other and the avian strains. Moreover, this method was clearly able to identify dubiously designated strains as well as mixtures of isolates within a single sample. In conclusion, this PCR approach based upon omp1 restriction mapping enables the differentiation of avian C. psittaci isolates and can be proposed as a taxonomic and epidemiologic tool.

Some binding properties of the envelope of Porphyromonas gingivalis to hemoglobin

Porphyromonas gingivalis was found to bind to hemoproteins (hemoglobin, myoglobin, catalase, cytochrome c) and the binding properties of the envelope of P. gingivalis to hemoglobin were investigated. Maximum amount of hemoglobin bound to 1 mg of the envelope was 58 micrograms. No significant binding was observed at 4 degrees C and the binding was inhibited strongly by tosyl-L-lysine chloromethyl ketone, Leupeptin, EDTA and partially by meta-periodate. Heating of the envelope at 70 degrees C for 15 min resulted in complete loss of the binding activity. The binding activity of the envelope was not influenced by the treatment with the endogenous proteases. The envelope saturated with hemoglobin could no longer bind to other hemoproteins tested, indicating that binding site for these hemoproteins are common.

Rapid detection of cytomegalovirus DNA in sera using the polymerase chain reaction: relationship with clinical diagnosis of cytomegalovirus infection after renal transplantation

A 21-year-old man had chronic renal failure and received a renal transplant. We used the polymerase chain reaction technique to detect cytomegalovirus (CMV) DNA in serum, blood, and urine for the diagnosis of CMV infection after the renal transplantation. CMV DNA in the serum was detected by polymerase chain reaction only during the active stage, while CMV DNA in urine and blood was detected even during the silent stage of CMV infection. It is suggested that the use of the polymerase chain reaction in serum would be useful for the rapid diagnosis of active CMV infection.

Apoptosis in thyroid tissue from patients with Hashimoto's thyroiditis

To clarify whether apoptosis of thyroid follicular epithelial cells occurs at the tissue level in autoimmune thyroiditis, 17 specimens of thyroid tissues with Hashimoto's thyroiditis were stained for fragmented DNA. Almost all nuclei of follicular epithelial cells forming atrophic thyroid follicles surrounded by mononuclear cell infiltration and fibrosis showed positive staining. With increasing distance from lymphoid cell follicles, the percentage of follicular epithelial cells with DNA fragmentation-positive nuclei decreased (30-80%). Electron microscopic study revealed the existence of epithelial cells with shrunk and condensed nuclei. The frequency of those cells in different areas was almost compatible with that of cells with fragmentation-positive nuclei. These findings suggest that apoptosis plays an important role in the thyroid tissue injury in autoimmune thyroiditis.

Epstein-Barr virus activity in patients on chronic hemodialysis

Patients with uremia are susceptible to viral infections, especially to Epstein-Barr virus (EBV). Sixty-one patients with end-stage renal diseases on chronic hemodialysis (HD), 14 patients with impaired renal function (CRF), and 27 healthy controls were studied with regard to EBV infection. Uremic patients (HD and CRF) had a significantly higher incidence of EBV infection and higher titers of anti-EBV VCA-IgG antibody than healthy controls. The anti-EBNA-1 titer was significantly higher in patients whose dialysis period was more than 3 months than in whom the dialysis period was 3 months or less. Immunoblotting analysis also showed stronger EBNA-1 signals in hemodialysis patients than EBNA-2, which was strongly detected in the CRF group and in healthy controls. EBV DNA was detected by Southern blot hybridization after PCR amplification of peripheral leukocytes, and occurred at a greater incidence in hemodialysis patients than in the other groups. Taken together, these results demonstrated that hemodialysis patients had persistent EBV infection.

A beta 2-agonist, procaterol, inhibits basophil migration

Beta 2-receptor agonists have recently been reported to be effective on allergen-induced late-phase reaction (LPR) in addition to their inhibitory effect on immediate-phase reaction, although the precise mechanism is not fully understood. In this study, we tested the effect of a selective beta 2-agonist, procaterol, on human basophil migration, which may be an important characteristic of LPR. Procaterol inhibited IL-8- and C5a-induced basophil migration in a dose-dependent fashion; 10(-7) M of procaterol reduced 30% of migration induced by both factors. The action of procaterol was rapid since the inhibition of migration was detected without preincubation and was not via the toxic effect on basophils as assessed by trypan blue test. The results of this study extend the repertoire of anti-inflammatory actions of beta 2-agonists.

Induction of eosinophil cytokine generation by chemoattractants

Recent studies have shown that eosinophils are capable of generating and releasing cytokines, illustrating a novel biologic aspect of eosinophils in regulating allergic inflammation by either autocrine or paracrine mechanisms. The effect of chemotactic agonists on eosinophil cytokine generation was examined by determination of interleukin-8 (IL-8) as a main parameter. Both complement C5a and N-formyl-methionyl-leucyl-phenylalanine (FMLP) stimulated eosinophils to release IL-8, but platelet activating factor (PAF) did not exert any significant effects. The generation of IL-8 by chemoattractants was absolutely dependent on the presence of cytochalasin B. Pertussis toxin completely attenuated C5a- and FMLP-induced IL-8 production, indicating the involvement of pertussis toxin-sensitive G proteins in the signal transduction process. In situ hybridization showed that both C5a and FMLP promoted eosinophil IL-8 production via transcriptional gene activation. Furthermore, C5a and FMLP, but not PAF, induced significant secretion of granulocyte-macrophage colony-stimulating factor from eosinophils. These results indicate that C5a and FMLP stimulate eosinophils to elaborate cytokines, which could be an important mechanism in the regulation of allergic inflammation.