High molecular weight organic compounds (HMW-OCs) in severe winter haze: Direct observation and insights on the formation mechanism

High molecular weight organic compounds (HMW-OCs), formed as secondary organic aerosols (SOA), have been reported in many laboratory studies. However, little evidence of HMW-OCs formation, in particular during winter season in the real atmosphere, has been reported. In January 2013, Beijing faced historically severe haze pollution, in which the hourly PM_2.5 concentration reached as high as 974 μg m^-3. Four typical haze events (HE1 to HE4) were identified, and HE2 (Jan. 9-16) was the most serious of these. Based on the hourly observed chemical composition of PM_2.5 and the daily organic composition analyzed by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS), we found that abundant ion peaks in m/z 200-850 appeared on heavy haze days, whereas these were negligible on a clear day, indicating the existence of HMW-OCs in the wintertime haze. A negative nonlinear correlation between HMW-OCs and O₃ suggested that gas oxidation was not likely to be the dominant mechanism for HMW-OCs formation. During the heavy haze events, the relative humidity and mass ratio of H₂O/PM_2.5 reached as high as 80% and 0.2, respectively. The high water content and its good positive correlation with HMW-OCs indicated that an aqueous-phase process may be a significant pathway in wintertime. The evidence that acidity was much higher during HE2 (0.37 μg m^-3) than on other days, as well as its strong correlation with HMW-OCs, indicated that acid-catalyzed reactions likely resulted in HMW-OCs formation during the heavy winter haze in Beijing.

Effects of DNA on immunoglobulin production stimulating activity of alcohol dehydrogenase

Alcohol dehydrogenase-I (ADH-I) derived from horse liver stimulated IgM production by human-human hybridoma, HB4C5 cells and lymphocytes. The IPSF activity of ADH-I was suppressed by coexistence of short DNA whose chain length is less than 200 base pairs (bp) and fibrous DNA in a dose-dependent manner. These DNA preparations completely inhibited the IPSF activity at the concentration of 250 mug/ml and 1.0 mg/ml, respectively. DNA sample termed long DNA whose average chain length is 400-7000 bp slightly stimulated IPSF activity at 0.06 mug/ml. However, long DNA suppressed IPSF activity by half at 1.0 mg/ml. The laser confocal microscopic analysis had revealed that ADH-I was incorporated by HB4C5 cells. The uptake of ADH-I was strongly inhibited by short DNA and fibrous DNA. However, long DNA did not suppress the internalization of ADH-I into HB4C5 cells. These findings indicate that short DNA and fibrous DNA depress IPSF activity of ADH-I by inhibiting the internalization of this enzyme. According to the gel-filtration analysis using HPLC, ADH-I did not directly interact with short DNA. It is expected from these findings that short DNA influences HB4C5 cells to suppress the internalization of ADH-I. Moreover, these facts also strongly suggest that ADH-I acts as IPSF after internalization into the cell.

Anaesthetic management of 27 cases of boron neutron capture therapy for glioblastoma

Twenty-seven patients received boron neutron capture therapy during craniotomy at our research reactor from 1991 to 1999. This is a form of intra-operative radiation therapy, which uses neutrons from a nuclear reactor. There are three additional major problems to anaesthetists: boron neutron capture therapy must be given beside the nuclear reactor, with no hospital facilities; neutrons cannot be shielded effectively by ordinary protectors; and neutrons are detrimental to metal devices and especially to electrical appliances. Boron neutron capture therapy has been adopted as an effective therapy for glioblastoma/astrocytoma, but special considerations are required for anaesthesia.

Pharmacological properties of calcium entry channels in A7r5 cells activated by endothelin-1

Using whole-cell recordings of patch-clamp and monitoring of the intracellular free calcium (Ca2+) concentration ([Ca2+]i), we characterized Ca2+ entry channels in A7r5 cells activated by endothelin-1 (ET-1). ET-1 activates three types of voltage-independent Ca2+ entry channels: two types of Ca2+-permeable nonselective cation channels (designated NSCC-1 and NSCC-2) and store-operated Ca2+ channel (SOCC). Furthermore, it was found that these channels can be discriminated pharmacologically using Ca2+ channel blockers such as 1-[beta-[3-(4-methoxyphenyl)propoxy]-4-methoxyphenethyl)-1-H-imidazoe l hydrochloride (SK&F 96365) and (RS)-(3,4-dihydro-6,7-dimethoxyisoquinoline-1-gamma l)-2-phenyl-N,N-di-[2-(2,3,4-trimethoxyphenyl)ethoxyl]acetamide (LOE 908). NSCC-1 is resistant to SK&F 96365 but sensitive to LOE 908, whereas NSCC-2 is sensitive to both drugs: SOCC is sensitive to SK&F 96365 but resistant to LOE 908. Using these channel blockers, we analyzed the Ca2+ entry channels involved in the ET-1-induced increase in [Ca2+]i of the cells. The increase induced by lower concentrations of ET-1 (< or = 0.1 nM) was unaffected by SK&F 96365 but it was abolished by LOE 908. In contrast, the increase caused by higher concentrations of ET-1 (> or = 1 nM) was suppressed by SK&F 96365 or LOE 908 to about 35% of controls, and abolished by combined treatment with SK&F 96365 and LOE 908. These results show that the increase in [Ca2+]i resulting from lower concentrations of ET-1 (< or = 0.1 nM) involves Ca2+ entry through only NSCC-1, whereas that resulting from higher concentrations of ET-1 involves Ca2+ entry through NSCC-1, NSCC-2 and SOCC, contributing 35%, 30% and 30%, respectively, to total Ca2+ entry.

[Intraoperative autologous blood transfusion was effective in a massive blood loss during living-related donor liver transplantation]

We have experienced massive blood loss (> 80,000 g) during living-related donor liver transplantation (LRDLT) of a 14-year old girl with biliary atresia. As available homologous blood was not sufficient, we transfused autologous blood (13,400 ml) during operation. Although immunosuppressant was administered to the patient, severe infection did not occur for 10 days after the operation. Cold ischemia time of the graft liver was about 16 hr, but her postoperative liver function was well-maintained. The case suggests that intraoperative autologus blood transfusion is effective if homologous blood is insufficient during LRDLT.

Pharmacological characterization of receptor-mediated Ca2+ entry in endothelin-1-induced catecholamine release from cultured bovine adrenal chromaffin cells

To clarify the mechanism for the endothelin-1 (ET-1)-induced release of catecholamines from the adrenal gland, we examined the effects of removal of extracellular Ca2+, blockers of L-, N-, P- and Q-types of voltage-operated Ca2+ channels (VOCC) such as nifedipine (L-type), omega-conotoxin GVIA (N-type), omega-agatoxin IVA (P-type) and omega-conotoxin MVIIC (Q-type) and blockers of voltage-independent Ca2+ entry channel such as SK&F 96365 and LOE 908 on release of catecholamines, the cytosolic free Ca2+ concentration ([Ca2+]i), and 45Ca2+ uptake in cultured bovine adrenal chromaffin cells. ET-1 but not ET-3 induced increases in release of catecholamines, [Ca2+]i, and 45Ca2+ uptake. The responses to ET-1 were abolished by the antagonist for ET(A) receptors, BQ-123, but not by the antagonist for ET(B) receptors, BQ-788, and they were abolished by removal of extracellular Ca2+. The increases were only partially inhibited (to about 65% of control) by nifedipine but unaffected by any of the omega-toxins. The nifedipine-resistant increase was inhibited by SK&F 96365 (to about 40%) and abolished by LOE 908 alone. These results indicate that ET-1 augments the release of catecholamines from adrenal chromaffin cells through ET(A) receptors, by activating two types of Ca2+ entry channels in addition to L-type VOCC: one (nonselective cation channel-1; NSCC-1) is sensitive to LOE 908 but resistant to SK&F 96365, whereas the other (NSCC-2) is sensitive to both LOE 908 and SK&F 96365.

Activation of three types of voltage-independent Ca2+ channel in A7r5 cells by endothelin-1 as revealed by a novel Ca2+ channel blocker LOE 908

1. We have shown that in addition to voltage-operated Ca2+ channel (VOC), endothelin-1 (ET-1) activates two types of Ca2+-permeable nonselective cation channel (NSCC) in A7r5 cells: its lower concentrations (< or = 1 nM; lower [ET-1]) activate only an SK&F 96365-resistant channel (NSCC-1), whereas its higher concentrations (> or = 10 nM; higher [ET-1]) activate an SK&F 96365-sensitive channel (NSCC-2) as well. 2. We now characterized the effects of a blocker of Ca2+ entry channel LOE 908 on NSCCs and store-operated Ca2+ channel (SOCC) in A7r5 cells, and using two drugs, clarified the involvement of these channels in the ET-1-induced increase in the intracellular free Ca2+ concentrations ([Ca2+]i). Whole-cell recordings and [Ca2+]i monitoring with fluo-3 were used. 3. LOE 908 up to 10 microM had no effect on increases in [Ca2+]i induced by thapsigargin or ionomycin, but SK&F 96365 abolished them. 4. In the cells clamped at -60 mV, both lower and higher [ET-1] induced inward currents with linear iv relationships and the reversal potentials of -15.0 mV. Thapsigargin induced no currents. 5. In the presence of nifedipine, lower [ET-1] induced a sustained increase in [Ca2+]i, whereas higher [ET-1] induced a transient peak and a sustained increase. The sustained increases by lower and higher [ET-1] were abolished by removal of extracellular Ca2+, and they were suppressed by LOE 908 to 0 and 35%, respectively, with the LOE 908-resistant part being abolished by SK&F 96365. 6. These results show that LOE 908 is a blocker of NSCCs without effect on SOCC, and that the increase in [Ca2+]i at lower [ET-1] results from Ca2+ entry through NSCC-1 in addition to VOC, whereas the increase at higher [ET-1] involves NSCC-1, NSCC-2 and SOCC in addition to VOC.

Physiological role of Ca2+-permeable nonselective cation channel in endothelin-1-induced contraction of rabbit aorta

We previously showed a role for a nonselective cation channel (NSCC) in the ETA-dependent action of endothelin-1 in mouse fibroblast and rabbit aortic smooth-muscle cell. To clarify the physiological significance of NSCCs in endothelin-1 (ET-1)-induced vasocontraction, we examined the effects of NSCC blockers such as mefenamic acid and SK&F 96365 on the contractions of deendothelialized rabbit aortic rings induced by a low (10[-10] M) or high (10[-8] M) concentration of ET-1. Mefenamic acid (< or =10[-3] M) had little effect on the contraction induced by 45 x 10(-3) M K+ or 1 x 10(-6) M Bay K-8644 in combination with 15 x 10(-3) M K+, indicating that it does not affect voltage-operated calcium channels (VOCs) and contractile mechanisms. The contraction by a low concentration of ET-1 was abolished after removal of extracellular Ca2+, but it was reduced only to 50% by a maximally effective concentration (10[-5] M) of nifedipine, an inhibitor of L-type VOCs (L-VOC). Mefenamic acid and SK&F 96365 inhibited the ET-1-induced contraction with 50% inhibitory concentration (IC50) values of 10(-4) M and 2 x 10(-5) M, respectively, and abolished it at 10(-3) M and 10(-4) M. By contrast, nifedipine, mefenamic acid, or SK&F 96365 had little effect on the contraction by a high concentration of ET-1. The contraction induced by a low or high concentration of ET-1 was abolished by an ETA antagonist, BQ-123, but not by an ETB antagonist, BQ-788. These results demonstrate that the contraction induced by ET-1 is totally mediated exclusively by ETA, but that Ca2+ entry through NSCCs in addition to L-VOCs plays an important role in contractions induced by low concentrations of ET-1, whereas it plays only a minor role in contractions induced by high concentrations of ET-1.

Alcohol dehydrogenase-I from horse liver stimulates immunoglobulin production by human hybridoma and human peripheral blood lymphocytes

Immunoglobulin production stimulating activity of alcohol dehydrogenase [EC 1.1.1.1] was assessed. Alcohol dehydrogenase-I (ADH-I) derived from horse liver stimulated IgM production by human-human hybridoma, HB4C5 cells producing human lung cancer specific monoclonal IgM. IgM production of HB4C5 cells was enhanced more than 6 fold by the addition of ADH-I at 400 microg/ml under serum-free condition. However, yeast derived ADHs, such as ADH-II and -III were ineffective to accelerate immunoglobulin production of the hybridoma line. These results imply that the immunoglobulin production stimulating effect of ADH-I is irrelevant to its enzymatic function, and defined as a novel feature of ADH-I. This enzyme also stimulated IgM and IgG production by human peripheral blood lymphocytes 2.9 fold and 1.4 fold, respectively. This fact suggests that ADH-I stimulates immunoglobulin production not only by specific hybridoma cell line, but also by non-specific immunoglobulin producers.

A study of learning splice sites of DNA sequence by neural networks

To predict of splice sites in DNA sequence, we developed a neural network system with back propagation. This system has a flexible network definition language which can describe any network structure. Three types of neural network were defined using the system for the prediction of splice sites. The neural networks are trained by the arrangements of bases around the splice sites of DNA sequences. The results of simulation showed the excellent ability of the neural networks to predict splice sites by applying and testing the arrangements of DNA sequences. This system also were used to predict the effects of point mutations on the splicing of the IX factor gene which may cause hereditary disease.

A method to estimate effects of amino acid substitutions in blood coagulation factor IX from hemophilia B patients

Hemophilia B is a hereditary disease caused by defects in coagulation factor IX. Accumulation of sequence data in the hemophilia B database makes it possible to study this disease at the molecular level. The most common mutations reported in the database are amino acid substitutions. Activity of factor IX in a patient's blood depends on a position of the substitution and combination of original and substituting amino acids. We have developed a method to estimate the effects of amino acid substitutions in factor IX of hemophilia B patients. We adopted two kinds of scores: (1) amino acid homology matrices, and (2) distances obtained from physical-chemical properties of amino acids. We found that: (1) the distance obtained from molecular volume shows the highest correlation with factor IX activity among four physical-chemical properties of amino acids, and (2) Dayhoff's 250PAM matrix gives the highest correlation among three homology matrices. We performed a multiple regression analysis for the estimation of factor IX activity by using four amino acid parameters and obtained a distance matrix, which gives the multiple correlation coefficient 0.6. Hemophilia is a hereditary, X-linked, recessive hemorrhagic disorder. About three-fourths of patients with hemophilia have the A type which is due to deficient factor VIII activity. The B type is less frequent than the A type and is due to deficient factor IX activity. Factor IX is a vitamin K dependent plasma protein that participates in the middle phase of blood coagulation. The entire nucleotide sequence of the factor IX gene was reported by Yoshitake et. al. There have been reported a variety of defects in the factor IX gene from hemophilia B patients, and these are summarized in the hemophilia B database. The effects of amino acid substitutions on the activities of factor IX depends on two factors. One is the combination of native and hemophilic amino acids, the differences of physical-chemical properties of the amino acids. Another is the position of mutation in factor IX protein. In this study, we analyzed missense mutations in the database described with factor IX activity values. Among them, the cases with double mutations were excluded from the analysis, leaving 255 cases. The number of unique mutations are 127. We have introduced distances between 20 amino acids by using the following four physical-chemical properties: (1) Molecular volume, (2)Hydropathy, (3) Polar requirement, and (4) Isoelectric point. We also adopted three homology matrices. These matrices are symmetric and composed of 20 x 20 elements, corresponding to amino acid pairs: (1)Dayhoff's 250 PAM matrix, (2) SCM (Structure-derived Correlation Matrix), and (3) SSM (Structure Superposition Matrix). This analysis shows that the highest correlation with factor á¿ activity is 0.47 given by molecular volume. The second one is 0.4 of Dayhoff's 250 PAM matrix. The multiple regression analysis, using four physicalchemical properties of amino acids, gives a correlation coefficient of 0.60. The amino acid distance obtained by the multiple regression analysis provides a useful measure to estimate the severity of the disease caused by a missense mutation. For example, if the distance between native and hemophilic amino acids is less than 1.5, the ratios of severe cases (activity is less than or equal to 1% of the normal), moderate cases (less than or equal to 4%), and mild cases are 67%, 27% and 6%, respectively.

A general purpose neural network simulator system for medical data processing

We developed a general purpose neural network simulator system for medical data processing. This system has a flexible network definition language. Users can define arbitrary hierarchical neural networks using the definition language to analyze medical data that contains some complex patterns. The learning algorithm used in this system is back propagation. Learning curves are displayed on multiple windows. This is a general purpose system, so it can be used for various kinds of medical data processing such as one dimensional signal processing or two dimensional image processing. The system can run on a standard UNIX workstation, which is faster and more powerful than most personal computers. The system needs an X window system/Motif and C compiler. These are standard system programs already available on most UNIX workstations. The source code of the system can be retrieved from our anonymous ftp site via Internet.

Novel rod-shaped viruses isolated from garlic, Allium sativum, possessing a unique genome organization

Rod-shaped flexuous viruses were partially purified from garlic plants (Allium sativum) showing typical mosaic symptoms. The genome was shown to be composed of RNA with a poly(A) tail of an estimated size of 10 kb as shown by denaturing agarose gel electrophoresis. We constructed cDNA libraries and screened four independent clones, which were designated GV-A, GV-B, GV-C and GV-D, using Northern and Southern blot hybridization. Nucleotide sequence determination of the cDNAs, two of which correspond to nearly one-third of the virus genomic RNA, shows that all of these viruses possess an identical genomic structure and that also at least four proteins are encoded in the viral cDNA, their M(r)s being estimated to be 15K, 27K, 40K and 11K. The 15K open reading frame (ORF) encodes the core-like sequence of a zinc finger protein preceded by a cluster of basic amino acid residues. The 27K ORF probably encodes the viral coat protein (CP), based on both the existence of some conserved sequences observed in many other rod-shaped or flexuous virus CPs and an overall amino acid sequence similarity to potexvirus and carlavirus CPs. The 11K ORF shows significant amino acid sequence similarities to the corresponding 12K proteins of the potexviruses and carlaviruses. On the other hand, the 40K ORF product does not resemble any other plant virus gene products reported so far. The genomic organization in the 3' region of the garlic viruses resembles, but clearly differs from, that of carlaviruses. Phylogenetic analysis based upon the amino acid sequence of the viral capsid protein also indicates that the garlic viruses have a unique and distinct domain different from those of the potexvirus and carlavirus groups. The results suggest that the garlic viruses described here belong to an unclassified and new virus group closely related to the carlaviruses.

Online support functions of prescription order system and prescription audit in an integrated hospital information system

The role of the online prescription support functions of a prescription order entry system was analysed and the results of the prescription audit by pharmacists were examined. In the Kochi Medical School Hospital, an online prescription order system has been developed as part of an integrated hospital information system named IMIS (the Integrated Medical Information System), in which all the physicians enter their prescription orders into online display terminals. The prescription order entry system is provided with prescription support functions, which check the entered prescription data, issue warnings, and offer information about drugs or patients. The prescription order system reduces the incidence of simple prescription mistakes and greatly decreases the cases of inquiries by pharmacists. However, results of the analysis show that such functions as warnings of double order and repeated prescription of a drug do not work as well as expected. The system would thus require some kind of intelligence like that of the auditing pharmacists or that of the physicians with accurate knowledge of clinical pharmacology.

New control chart for multivariate data with missing values

A new multivariate statistical quality control method has been developed. It is an extension of the method developed by Kume, which is able to find abnormal values in multivariate biochemical data of a clinical laboratory. The present method makes use of the difference between two sets of data measured from the samples of the same patient obtained on different days. The Mahalanobis' distance between two samples can be calculated from the difference of their observations. If the Mahalanobis' distance of the two data is larger than the critical value decided in advance, the reliability of the measurement is doubtful. The characteristic of the present method is that it can apply to data with missing values by estimating them from measured data. Some numerical examples are shown to demonstrate the availability of the method.

Efficacy of a computerized system applied to central operating theatre for medical records collection

A computer system operation is introduced, which has been in use since October 1981 at Kochi medical school as one of the integral sub-systems of the total hospital information system called IMIS. The system was designed from the beginning with the main purposes of obtaining better management of operations, and detailed medical records are included for before, during and after operations. It is shown that almost all operations except emergencies were managed using the computer system rather than the paper system. After presenting some of the results of the accumulated records we will discuss the reason for this high frequency of use of the computer system.

Use of a computer in analysis of heart rate and blood pressure response to the Valsalva maneuver

The relationship between systolic blood pressure (SBP) and R-R interval (RR) in phase II of the Valsalva maneuver was analyzed with the use of a nonlinear relation. The nonlinear relation introduced here includes time derivatives of SBP and RR, and is a natural extension from the linear one which defines the linear baroreflex sensitivity index (BRSI). The model equations of SBP and RR derived from the nonlinear relation predicted well the observed changes of SBP and RR in 11 normotensive subjects and 16 hypertensive patients. Two of the parameters of the relation were related to the activity of the compensatory mechanism, and discriminated well the hypertensives from the normotensives. For this analysis an interactive system of regression analysis has been developed to reduce the difficulties in the case of nonlinear regression curve fitting. The regression curves can be monitored on a graphic terminal during every regression step. The values of nonlinear parameters can be obtained easily and systematically with use of the system.

Analysis of the online order entry process in an integrated hospital information system

In Kochi Medical School Hospital, many online order systems have been developed as a part of the integrated hospital information system named IMIS KOCHI. The prescription, laboratory and radiology orders are used frequently and entered into the system by physicians. The distribution of entry duration of these orders by physicians was analyzed and it was found that the order entry is a completely random event and the entry process consists of the two Poisson processes; the quick process and the slow process. The two Poisson processes were observed even in the do-prescription order without correction by trained physicians. It is speculated that the quick process depends on availability in the order entry system and the slow process depends on peculiarities in clinics, and the mental condition of physicians.

Evaluation of the "Mahalanobis' generalized distance" method of quality control: monitoring system of multivariate data

The purpose of this article is to evaluate the effectiveness of a monitoring system that utilizes the multivariate data. The system monitors the data of an individual patient by comparing them with his previous data. The Mahalanobis' generalized distance is introduced to measure the difference between the present and previous data. The authors applied this method to several sets of laboratory data, and it was shown to be useful for the monitoring system of laboratory errors. As a practical application, they developed a batch program and introduced it in the daily routine of the computer system. They expect that this method will be employed as a useful monitoring system in clinical laboratories, like the limit and delta checks.