Long-term culture of avian embryonic cells in vitro

The pH of the embryonic blood, one of the most important environmental factors for embryonic cells, was found to range from 8.1 to 8.5 in chick embryos until 108 h after incubation. Based on these results, the culture medium adjusted to pH 8.0 was used to culture embryonic chick and quail cells. They were easily subcultured for a long period of time at pH 8.0. This pH culture condition may have wide application for manipulating embryonic cells or tissues and establishing cell lines from avian embryos.

Association with capsid proteins promotes nuclear targeting of simian virus 40 DNA

All animal DNA viruses except pox virus utilize the cell nucleus as the site for virus reproduction. Yet, a critical viral infection process, nuclear targeting of the viral genome, is poorly understood. The role of capsid proteins in nuclear targeting of simian virus 40 (SV40) DNA, which is assessed by the nuclear accumulation of large tumor (T) antigen, the initial sign of the infectious process, was tested by two independent approaches: antibody interception experiments and reconstitution experiments. When antibody against viral capsid protein Vp1 or Vp3 was introduced into the cytoplasm, the nuclear accumulation of T antigen was not observed in cells either infected or cytoplasmically injected with virion. Nuclearly introduced anti-Vp3 IgG also showed the inhibitory effect. In the reconstitution experiments, SV40 DNA was allowed to interact with protein components of the virus, either empty particles or histones, and the resulting complexes were tested for the capability of protein components to target the DNA to the nucleus from cytoplasm as effectively as the targeting of DNA in the mature virion. In cells injected with empty particle-DNA, but not in minichromosome-injected cells, T antigen was observed as effectively as in SV40-injected cells. These results demonstrate that SV40 capsid proteins can facilitate transport of SV40 DNA into the nucleus and indicate that Vp3, one of the capsid proteins, accompanies SV40 DNA as it enters the nucleus during virus infection.

Functional complementation of nuclear targeting-defective mutants of simian virus 40 structural proteins

Structural proteins of simian virus 40 (SV40), Vp2 and Vp3 (Vp2/3) and Vp1, carry individual nuclear targeting signals, Vp3(198-206) (Vp2(316-324) and Vp1(1-8), respectively, which are encoded in different reading frames of an overlapping region of the genome. How signals coordinate nuclear targeting during virion morphogenesis was examined by using SV40 variants in which there is only one structural gene for Vp1 or Vp2/3, nuclear targeting-defective mutants thereof, Vp2/3(202T) and Vp1 delta N5, or nonoverlapping SV40 variants in which the genes for Vp1 and Vp2/3 are separated, and mutant derivatives of the gene carrying either one or both mutations. Nuclear targeting was assessed immunocytochemically following nuclear microinjection of the variant DNAs. When Vp2/3 and Vp1 mutants with defects in the nuclear targeting signals were expressed individually, the mutant proteins localized mostly to the cytoplasm. However, when mutant Vp2/3(202T) was coexpressed in the same cell along with wild-type Vp1, the mutant protein was effectively targeted to the nucleus. Likewise, the Vp1 delta N5 mutant protein was transported into the nucleus when wild-type Vp2/3 was expressed in the same cells. These results suggest that while Vp1 and Vp2/3 have independent nuclear targeting signals, additional signals, such as those defining protein-protein interactions, play a concerted role in nuclear localization along with the nuclear targeting signals of the individual proteins.

Induction of essential components of the superoxide generating system in human monoblastic leukemia U937 cells

Cytochrome b558 composed of large and small subunits, and cytosolic 47- and 65-kDa proteins are important constituents of the superoxide (O2-) generating system in phagocytes and B lymphocytes. In this paper, we describe changes in O2(-)-generating activity and expression of O2(-)-generating components during differentiation of human monoblastic leukemia U937 cells to macrophage-like cells. Undifferentiated U937 cells generated no O2- in response to a stimulation, although they expressed the three components other than the cytochrome b558 large subunit. When U937 cells were cultured with agents that induced the cell differentiation, such as vitamin D3, retinoic acid, interferon-gamma, and tumor necrosis factor, O2(-)-generating activity increased 5- to 200-fold depending on the agent used. Immunoblotting analysis revealed that the amounts of the four protein components essential for O2- generation increased, although their induction levels were significantly different between inducers. Among the four protein components, the cytochrome subunits were induced in low levels by all agents tested, which may explain why the O2(-)-generating activity of differentiated U937 cells was much lower than that of neutrophils from peripheral blood.

Enantiospecific determination of ibuprofen in rat plasma using chiral fluorescence derivatization reagent, (-)-2-[4-(1-aminoethyl)phenyl]-6- methoxybenzoxazole

A highly sensitive and reversed-phase high-performance liquid chromatographic method for the determination of the enantiomeric composition of ibuprofen in rat plasma is described. The method is based on the resolution of the diastereomeric amides formed on reaction of the ibuprofen enantiomers with (-)-2-[4-(1-aminoethyl)phenyl]-6-methoxybenzoxazole ((-)-APMB) in the presence of 2,2'-dipyridyl disulphide (DPDS) and triphenylphosphine (TPP) in dichloromethane. The reaction mixture was allowed to stand at room temperature for 5 min, and the reaction was completed by evaporation with a stream of nitrogen at 40 degrees C. The minimum quantifiable concentrations were 0.2 microgram/mL and 0.4 microgram/mL for S-ibuprofen and R-ibuprofen, respectively, in a 10 microL injection volume. The method was applied to the determination of enantiomeric ibuprofen in plasma after oral administration to rats.

Emergency intubation of the pediatric medical patient: use of anesthetic agents in the emergency department

STUDY OBJECTIVES

To delineate the diagnoses of children who required emergency intubation, to ascertain which medications were used, and to describe the complications of intubation and their association with the choice of medications. DESIGN, SETTING, AND TYPE OF PARTICIPANTS: Three-year retrospective study of 60 intubations of critically ill pediatric patients by pediatric emergency physicians in the emergency department setting.

MEASUREMENTS AND MAIN RESULTS

Clinical complications were noted for intubations with neuromuscular paralysis and intubations initially attempted without a paralyzing agent. Intubations attempted without neuromuscular paralysis resulted in a higher rate of complications (53% versus 26%) and a greater risk of more than one complication per intubation. This finding appeared to be independent of physicians' clinical experience.

CONCLUSION

Rapid-sequence protocols with paralysis facilitate intubations in the complex pediatric patient in the ED setting.

[ABO genotyping by polymerase chain reaction (PCR) and its application to paternity testing]

The authors describe the usefulness of ABO genotyping by polymerase chain reaction (PCR) in paternity testing. Blood samples were obtained from 80 unrelated Japanese (20 samples in each of phenotypes of the ABO blood group system) and 13 cases of disputed paternity. PCR amplification of DNA extracted from blood by a conventional extraction procedure was carried out using the primers (primer 1: CACCGTGGAAGGATGTCCTC; primer 2: AATGTCCACAGTCACTCGCC; primer 3: TGGAGATCCTGACTCCGCTG; primer 4: GTAGAAATCGCCCTCGTCCTT) described by Lee and Chang (J Forensic Sci, Vol. 37). The amplified DNA products using primer 1 and 2 and the amplified DNA products using primer 3 and 4 were digested with Kpn I and Alu I, respectively. The amplified and digested DNA products were then analysed by electrophoresis on polyacrylamide gels. The bands on gels stained with ethidium bromide were observed with UV light and with silver staining. In 20 samples of phenotype A, genotype AA was recognized in five samples and the others were genotype AO. In 20 samples of phenotype B, three samples were genotype BB and the others were genotype BO. According to this procedure, genotypes of phenotype AB and O were clearly and consistently confirmed. In 13 cases of disputed paternity, the paternity of six cases was excluded with some of red cell, serum protein, enzyme genetic markers and HLA systems except ABO phenotype. However, the paternity of three cases out of these six cases was excluded with ABO genotype. This study seems to support the usefulness of ABO genotyping by PCR in paternity testing.

[Adverse reactions to low osmolar iodine contrast media (second report)]

From January to December 1990, we performed a prospective survey of adverse reactions to contrast media at two different institutes of Juntendo University. We collected a total of 4555 case sheets during the period. The radiological procedures we investigated were computed tomography, intravenous urography, arteriography, venography and myelography. Low osmolar iodine contrast medium was used almost exclusively (except for five cases). The overall incidence of adverse reactions was 7.0%, and there were no severe or fatal reactions. The incidence of adverse reactions was higher in females (8.5%) than in males (6.1%). The incidence of adverse reactions increased according to the dose of contrast medium, especially when more than 101 ml was injected. Intra-arterial injection caused adverse reactions most often, followed by regular intravenous injections, followed by bolus intravenous injections. Adverse reactions occurred most often during injection. The next occurred in 5 minutes after injection, and then, 5-10 minutes after the injection of contrast medium. The incidence of adverse reactions was higher in patients with a history of allergy or previous reactions. Allergic adverse reactions were observed at a higher frequency. Pretesting was performed in 56.7% of the cases.

Direct evidence for interaction between COOH-terminal regions of cytochrome b558 subunits and cytosolic 47-kDa protein during activation of an O(2-)-generating system in neutrophils

Cytochrome b558 in phagocytes is a transmembrane protein composed of large and small subunits and considered to play a key role in O2- generation during the respiratory burst. The COOH-terminal regions of the cytochrome subunits protrude to the cytoplasmic side and are assumed to be the sites for association with cytosolic components to form an active O(2-)-generating complex (Imajoh-Ohmi, S., Tokita, K., Ochiai, H., Nakamura, M., and Kanegasaki, S. (1992) J. Biol. Chem. 267, 180-184). We show here that two synthetic peptides corresponding to the COOH-terminal region of each subunit inhibit NADPH-dependent oxygen uptake induced by sodium dodecyl sulfate (SDS) in a cell-free system consisting of plasma membrane and cytosol. The inhibition was observed when either peptide was added to the system before, but not after, the activation with SDS suggesting that interaction between the COOH-terminal regions of the cytochrome subunits and cytosolic components is important for the assembly and the activity of the O(2-)-generating system. Using the cross-linking reagent dimethyl 3,3'-dithiobis-propionimidate, we found that the cytosolic 47-kDa protein, an essential component of the O(2-)-generating system, interacted with the synthetic peptides in the presence of SDS. In addition to the 47-kDa protein, a 17-kDa protein was found to be associated with the peptide corresponding to the COOH-terminal region of the small subunit. These results indicate that the cytosolic COOH-terminal regions of cytochrome b558 subunits are the binding sites for both the cytosolic 47-kDa protein and the 17-kDa protein and that the binding takes place during activation of the system.

Phosphorylation and activation of tyrosine hydroxylase in PC18 cells: a cell line derived from rat pheochromocytoma PC12 cells

Treatment of rat pheochromocytoma PC18 cells (a variant subclone of PC12 cells) with forskolin produced increased activity and phosphorylation of tyrosine hydroxylase. In contrast, treatment of the PC18 cells with 56 mM K+, A23187, phorbol-12-myristate-13-acetate (PMA) or phorbol-12,13-dibutyrate (PDB) did not affect the activity and only slightly increased the phosphorylation of tyrosine hydroxylase. None of the treatments except forskolin increased cyclic AMP levels in PC18 cells. Furthermore, 45Ca2+ uptake into PC18 cells was not affected by 56 mM K+, PDB or forskolin; however, A23187 increased 45Ca2+ uptake 4-fold over basal uptake. Nevertheless, no activation and little increase in phosphorylation of tyrosine hydroxylase was observed in PC18 cells treated with A23187. When tyrosine hydroxylase levels in PC18 cells were elevated by treatment with dexamethasone, activation of tyrosine hydroxylase by 56 mM K+, PDB or A23187 was still not observed. Both purified Ca2+/calmodulin-dependent protein kinase and cyclic AMP-dependent protein kinase catalyzed the phosphorylation of tyrosine hydroxylase purified from PC18 cells in vitro. Furthermore, crude cell extracts from PC12 cells and PC18 cells possessed Ca2+/calmodulin-dependent protein kinase activity that catalyzed the phosphorylation of purified tyrosine hydroxylase. These results suggest that tyrosine hydroxylase activity in PC18 cells is regulated by a cyclic AMP-dependent mechanism. However, due to a number of abnormalities the Ca(2+)-dependent mechanisms do not result in the activation of tyrosine hydroxylase and only slightly increase the phosphorylation of the enzyme in PC18 cells.

Clinical assessment of carcinoma in situ of the human urinary bladder

Recent interest in intravesical instillation of bacillus Calmette-Guérin for the management of carcinoma in situ (CIS) of the bladder prompted us to review our results of total immediate cystourethrectomy. From 1975 to 1987, we surgically treated 302 patients with primary bladder tumours. Of these, 21 bladder tumours were histologically diagnosed as CIS, and total immediate cystourethrectomy was performed in all cases. The lesions were classified into three types: primary CIS accompanied by neither previous nor simultaneous tumours of the urinary tract (Type 1, 9 patients), concomitant CIS associated with superficial papillary tumour (Type 2, 6 patients), and secondary CIS detected during the follow-up period after treatment of the superficial papillary tumour (Type 3, 6 patients). Primary CIS was more often diagnosed according to subjective symptoms such as micturition pain than concomitant CIS. Secondary CIS was diagnosed in all patients by routine examinations including cytology and cystoscopy. There was no particular relationship between the time of recurrence of the tumour and the occurrence of secondary CIS. Within the same period, 60 patients with stage T1 bladder tumour were treated by total cystourethrectomy. The actuarial 5-year survival rate was 77% for T1 and 75% for CIS. The 5-year survival rate was 71% for Type 1, 83% for Type 2, and 67% for Type 3 CIS with no difference among the CIS types. Tumour invasion to the bladder, prostate, ureter, or lymph nodes was observed in 9 (42.9%) of the 21 patients, although cystourethrectomy was performed within 3 months of the diagnosis. Examination of ABH antigens did not allow prediction of invasion of CIS. Our findings suggest that the invasive potential of CIS may seriously limit the indications of conservative treatment against carcinoma in situ.

[Laryngeal fractures due presumably to tracheal intubation in resuscitation]

In three autopsy cases performed in our department, we observed the throat-skeleton fractures occurring presumably during the tracheal intubation in resuscitation. Case 1. 63-year-old man died of acute hemorrhagic pancreatitis shortly after the quarrel with a suspected person. The autopsy examination showed the fractured hyoid bone with haemorrhage at the fracture site. The question whether direct pressure on his neck by the suspected person results the fracture of the hyoid bone was investigated. Case 2. 75-year-old man treated for senile dementia was clubbed with a walking stick by the other patient treated for same disease and he died of traumatic shock. The fracture of the hyoid bone was also noted like case 1. The strike in the throat and/or the neck compression by the assailant were suspected of being the cause of this fracture. Case 3. 47-year-old man got the severe head injury during the quarrel. He died about two weeks after operation and the cause of death was multiple organ failure. The autopsy findings revealed the fracture of the superior thyroid horn. The neck compression by the suspected person was the questionable cause of this fracture. In all these cases, the asphyxia findings and the signs of the direct pressure on the neck by the assailants were not recognized other than the above-mentioned laryngeal fractures. From the autopsy findings, together with the criminal investigation, we consider collectively that the tracheal intubation in resuscitation induced presumably these laryngeal injuries. In general, throat-skeleton fractures seem to be the signs of homicidal violence against the neck.(ABSTRACT TRUNCATED AT 250 WORDS)

6-Acetonylisoxanthopterin: A Potent Inhibitor of Sepiapterin Reductase

The inhibitory effect of 6-/7-substituted (2'-oxo) pteridines and ichthyopterin was examined for sepiapterin reductase. 6-Acetonylisoxanthopterin and 6-acetonyl-2,4-diamino-7-hydroxypteridine showed pronounced competitive inhibitory effects to sepiapterin reductase and Ki values were 0.38 μM and 90 μM, respectively. Ichthyopterin and 6-acetonyl-7-hydroxylumazine showed weak noncompetitive inhibitory effects and Ki values were 2.4 mM and 1.1 mM, respectively. 7-Acetonylxanthopterin exhibited no inhibition to sepiapterin reductase.

Growth fraction of human bladder tumors

The growth fraction of bladder tumors was immunohistochemically assessed in situ using anti-DNA polymerase (Pol alpha) monoclonal antibody. This enzyme is known to be present in the nucleus of the cells in G1, S, and G2 phases. The percentage of labeled cells was expressed as the labeling index (LI). The average LI was 6.0% in normal epithelium and 17.8% in bladder tumors, this difference being significant. The labeled cells were distributed throughout both the basal and surface layers of bladder tumors. However, in some bladder tumors, the distribution of Pol alpha-labeled cells varied from area to area. The higher fraction of labeled cells was found in high grade or invasive tumors. Papillary and nodular bladder tumors showed a greater rate of cell proliferation than papillary tumors. These findings suggest that Pol alpha immunostaining could be a potent tool for easy and quick evaluation of proliferating cells in bladder tumors, thereby providing a supplement to conventional histological findings.

Characterization of palytoxin-induced catecholamine secretion from cultured bovine adrenal chromaffin cells. Effects of Na(+)- and Ca(2+)-channel blockers

The effect of palytoxin (PTX), a potent marine toxin, on catecholamine (CA) secretion from cultured bovine adrenal chromaffin cells was examined. PTX at concentrations of over 10(-10) M induced CA secretion concentration-dependently. About 40-50% of the total cellular CA was secreted during 20-min incubation with 3 x 10(-8) M PTX. PTX-induced CA secretion was dependent on both extracellular Na+ and Ca2+. PTX caused increases in [22Na](+)- and [45Ca](2+)-influxes into the cells. Increase in [22Na](+)-influx was observed at concentrations of over 10(-11) M PTX and was maximal at 10(-10) M PTX and then gradually decreased at higher concentrations that induced [45Ca](2+)-influx and CA secretion. On the other hand, increase in [45Ca](2+)-influx was observed at concentrations of over 10(-10) M PTX and increased with increase in concentration of PTX. This concentration-response curve for PTX-induced [45Ca](2+)-influx was similar to that for PTX-induced CA secretion. The CA secretion and [22Na](+)- and [45Ca](2+)-influxes induced by PTX were not affected by tetrodotoxin (TTX), but were significantly inhibited by quinidine and aprindine(mexiletine), antiarrythmic drugs known to block Na(+)-channels. Ca(2+)-channel blockers such as nifedipine, verapamil, Co2+, Cd2+, inhibited both CA secretion and [45Ca](2+)-influx induced by PTX. These results indicate that PTX-induced CA secretion is mediated by activation of Na(+)-dependent, TTX-insensitive voltage-dependent Ca(2+)-channels, and is inhibited by quinidine and aprindine through their inhibitory effects on the Na(+)- and Ca(2+)-influxes into the cells induced by PTX.