Quantitative measurement of airborne particles during endoscopic and microscopic ear surgery in the operating room.

OBJECTIVE: This study aimed to quantitatively investigate airborne particle load in the operating room during endoscopic or microscopic epitympanectomy or mastoidectomy. METHOD: In the transcanal endoscopic ear surgery group, drilling was performed underwater. A particle counter was used to measure the particle load before, during and after drilling during transcanal endoscopic ear surgery or microscopic ear surgery. The device counted the numbers of airborne particles of 0.3, 0.5 or 1.0 µm in diameter. RESULTS: The particle load during drilling was significantly higher in the microscopic ear surgery group (n = 5) than in the transcanal endoscopic ear surgery group (n = 11) for all particle sizes (p < 0.01). In the transcanal endoscopic ear surgery group, no significant differences among the particle load observed before, during and after drilling were seen for any of the particle sizes. CONCLUSION: Bone dissection carries a lower risk of airborne infection if it is performed using the endoscopic underwater drilling technique.

An endoscopic hydro-mastoidectomy technique for cholesteatoma surgery.

OBJECTIVE: Endoscopic hydro-mastoidectomy, in which mastoidectomy is performed underwater, can be employed during transcanal endoscopic ear surgery for cholesteatoma removal. It was hypothesised that endoscopic hydro-mastoidectomy might take less time than endoscopic non-underwater mastoidectomy because the endoscope does not need to be removed for cleaning. METHODS: This study compared the mastoidectomy and total operative durations between the endoscopic hydro-mastoidectomy (n = 25) and endoscopic non-underwater drilling (control, n = 8) groups. Moreover, it compared the size of resected areas of the external auditory canal between the two groups. RESULTS: The mastoidectomy time of the endoscopic hydro-mastoidectomy group was significantly shorter than that of the control group (p < 0.01). The total operative time did not differ significantly between the endoscopic hydro-mastoidectomy and control groups (p = 0.17). The resected area was significantly larger in the endoscopic hydro-mastoidectomy group than in the control group (p < 0.05). CONCLUSION: Endoscopic hydro-mastoidectomy enables more extensive bone resection within a shorter period.

The sugar ring conformation of 4'-ethynyl-2-fluoro-2'-deoxyadenosine and its recognition by the polymerase active site of HIV reverse transcriptase.

4' Ethynyl-2-fluoro-2'-deoxyadenosine (EFdA) is the most potent inhibitor of HIV reverse transcriptase (RT). We have recently named EFdA a Translocation Defective RT Inhibitor (TDRTI) because after its incorporation in the nucleic acid it blocks DNA polymerization, primarily by preventing translocation of RT on the template/primer that has EFdA at the 3'-primer end (T/PEFdA). The sugar ring conformation of EFdA may also influence RT inhibition by a) affecting the binding of EFdA triphosphate (EFdATP) at the RT active site and/or b) by preventing proper positioning of the 3'-OH of EFdA in T/PEFdA that is required for efficient DNA synthesis. Specifically, the North (C2'-exo/C3'-endo), but not the South (C2'-endo/C3'-exo) nucleotide sugar ring conformation is required for efficient binding at the primer-binding and polymerase active sites of RT. In this study we use nuclear magnetic resonance (NMR) spectroscopy experiments to determine the sugar ring conformation of EFdA. We find that unlike adenosine nucleosides unsubstituted at the 4'-position, the sugar ring of EFdA is primarily in the North conformation. This difference in sugar ring puckering likely contributes to the more efficient incorporation of EFdATP by RT than dATP. In addition, it suggests that the 3'-OH of EFdA in T/PEFdA is not likely to prevent incorporation of additional nucleotides and thus it does not contribute to the mechanism of RT inhibition. This study provides the first insights into how structural attributes of EFdA affect its antiviral potency through interactions with its RT target.

Development of ICF code selection tools for mental health care.

BACKGROUND: The International Classification of Functioning, Disability and Health (ICF) has been available as a means of coding life functions but the coding process is cumbersome due to the large number of ICF codes. In the current study, we developed ICF code selection tools to support the coding of activity and participation data recorded in domiciliary mental health care reports. METHODS: We first developed a search system to facilitate the selection of ICF codes by tracking back through codes' conceptual trees using a directory tool. We performed a morphological analysis on the training data set to correlate nouns with the ICF codes and obtained an analysis corpus to which numerical scores representing the frequencies of associated ICF codes for each noun were assigned. Based on the obtained corpus we developed a full-text search tool, which could simplify ICF coding relative to that performed using the directory tool. We then evaluated the usefulness of the former tool on the test data set. RESULTS: Using the full-text search tool, correct ICF codes were recorded in the first candidate list for only 54.2% of sentences. However, correct ICF codes appeared on the combined candidate lists for 90.1% of sentences and on the top three candidate lists for 71.7%. In a specific case (General Tasks and Demands), 100% of the correct codes were included on the combined candidate lists. CONCLUSION: We developed selection tools that effectively supported ICF coding, although it was impossible to fully automate ICF coding. This indicated that ICF codes could more effectively be applied to mental health care.

Development of a nosocomial outbreak investigation database.

A pilot web-based database was created to facilitate epidemiological investigation of nosocomial outbreaks. The database provides highly structured abstracts in a case study format to serve as a guide for investigations. Problems encountered in abstracting over 330 published reports included missing information and classification of study methods. The database offers a new way to review outbreaks, for example, in terms of their impact measured by various combinations of database fields, such as the number of cases, attack rate, pathogens, service/ward and mode of transmission. Feedback from users of the database suggests its usefulness. Creation of a large web-based database seems to be both desirable and feasible.

Investigation and evaluation of the change in the outpatients flow before and after the move of the hospital.

In order to estimate the changes in the service for outpatients with hospital movement, patient flow investigation has been performed at both old and new hospitals. IC memory card was handed out to each outpatient, and timestamps and places were recorded on the card at the places that the patient have been by using card writers set at each department. By comparing with two results, old and new hospitals, patient-waiting time at payment counter was remarkably shortened because of the effect of order-entry system. However, there were few changes in stay time at clinical departments. From the results, it is found that optimization of booking system was required for improvement of patients flow at clinical departments.

Monocyte chemoattractant protein 1 causes differential signalling mediated by proline-rich tyrosine kinase 2 in THP-1 cells.

Monocyte chemoattractant protein 1 (MCP-1) has a crucial role in atherogenesis and inflammation. However, MCP-1-mediated signalling pathways in monocytes have not been fully elucidated. In the present study we investigated the role of tyrosine kinases such as proline-rich tyrosine kinase 2 (Pyk2) in MCP-1-mediated signal transduction in the monocytic cell line THP-1. Pyk2 was tyrosine phosphorylated very quickly after stimulation with MCP-1. We found that Lyn, Shc and paxillin were also tyrosine phosphorylated by MCP-1. We examined the association of these molecules by immunoprecipitation and immunoblot analysis. The association of Pyk2 with Lyn was dependent on stimulation with MCP-1 and on tyrosine phosphorylation of Pyk2. Phosphorylation of p38 was also dependent on tyrosine phosphorylation of Pyk2. However, the association of Pyk2 with paxillin and Grb2 was not affected by stimulation with MCP-1. Phosphorylation of ERK (extracellular-signal-regulated protein kinase) was not affected by overexpression of kinase-negative Pyk2. Our results indicate that Pyk2 forms a complex with paxillin, Grb2 and Lyn in THP-1 cells. However, Pyk2 is not always involved in MCP-1-mediated signalling pathways.

Distinct signaling pathways for MCP-1-dependent integrin activation and chemotaxis.

Transmigration of monocytes to the subendothelial space is the initial step of atherosclerotic plaque formation and inflammation. Integrin activation and chemotaxis are two important functions involved in monocyte transmigration. To delineate the signaling cascades leading to integrin activation and chemotaxis by monocyte chemoattractant protein-1 (MCP-1), we have investigated the roles of MAPK and Rho GTPases in THP-1 cells, a monocytic cell line. MCP-1 stimulated beta1 integrin-dependent, but not beta2 integrin-dependent cell adhesion in a time-dependent manner. MCP-1-mediated cell adhesion was inhibited by a MEK inhibitor but not by a p38-MAPK inhibitor. In contrast, MCP-1-mediated chemotaxis was inhibited by the p38-MAPK inhibitor but not by the MEK inhibitor. The inhibitor of Rho GTPase, C3 exoenzyme, and a Rho kinase inhibitor abrogated MCP-1-dependent chemotaxis but not integrin-dependent cell adhesion. Further, C3 exoenzyme and the Rho kinase inhibitor blocked MCP-1-dependent p38-MAPK activation. These data indicate that ERK is responsible for integrin activation, that p38-MAPK and Rho are responsible for chemotaxis mediated by MCP-1, and that Rho and the Rho kinase are upstream of p38-MAPK in MCP-1-mediated signaling. This study demonstrates that two distinct MAPKs regulate two dependent signaling cascades leading to integrin activation and chemotaxis induced by MCP-1 in THP-1 cells.

Orientation of bull sperms in static magnetic fields.

The orientation of bull sperm cells in static magnetic fields was investigated by microscopic observation. The bull sperm, which has a very flat head, was fixed and its motion was stopped by glutaraldehyde. It was oriented with the whole body and the flat head perpendicular to the direction of the magnetic field. The diamagnetic cell components, such as the cell membrane, the DNA in the head, and the microtubule in the tail, were thought to contribute to this orientation, because bull sperm does not have paramagnetic components. For quantitative measurement of the orientation, the intensity of transmitted light through glutaraldehyde-fixed bull sperm suspension in a photometric cell was determined. The intensity changed slightly in proportion to the mean degree of orientation of the sperms. It increased sigmoidally depending on the intensity of the magnetic field and reached 100% at just below 1 T. The magnetic orientation is very strong in comparison to that of erythrocytes or platelets. By studying the response of the bull sperm to the magnetic field, it will be possible to understand its microstructure in more detail.

Differential signaling for MCP-1-dependent integrin activation and chemotaxis.

Transmigration of monocytes to the subendothelial space is the initial step in atherosclerotic plaque formation and inflammation. Integrin activation and chemotaxis are two important functions in monocyte transmigration. To delineate the signaling cascades leading to integrin activation and chemotaxis by monocyte chemoattractant protein-1 (MCP-1), we investigated the roles of MAPK in THP-1 cells, a monocytic cell line. MCP-1 stimulated beta1 integrin-dependent, but not beta2 integrin-dependent cell adhesion in a time-dependent manner. MCP-1-mediated cell adhesion was inhibited by a MEK inhibitor, but not by a p38-MAPK inhibitor. By contrast, MCP-1-mediated chemotaxis was inhibited by the p38-MAPK inhibitor, but not by the MEK inhibitor. These data indicate that ERK is responsible for integrin activation and that p38-MAPK is responsible for chemotaxis mediated by MCP-1. This study demonstrates that two distinct MAPKs regulate two dependent signaling cascades, leading to integrin activation and chemotaxis induced by MCP-1 in THP-1 cells.

Synthesis and biological activities of 2'-deoxy-2'-fluoro-4'-thioarabinofuranosylpyrimidine and -purine nucleosides.

As part of our ongoing investigation of the synthesis of biologically interesting 2'-modified-4'-thionucleosides, we synthesized 2'-deoxy-2'-fluoro-4'-thioarabinofuranosylpyrimidine and -purine nucleosides, and evaluated their antiviral and antitumor activities. In the pyrimidine series, beta-anomers of 5-ethyluracil, 5-iodouracil, 5-chloroethyluracil, and 5-iodocytosine derivatives showed potent and selective anti-HSV-1 and HSV-2 activities in vitro. In the purine series, guanine and 2,6-diaminopurine derivatives showed prominent antiviral activities with slight cytotoxicity. On the other hand, the 5-fluorocytosine derivative (5F-4'-thioFAC) showed potent antitumor activity against both leukemia and solid tumor. Its antitumor spectrum against 14 human solid tumor and one leukemic cell lines was compared with that of 4'-thioFAC. The results showed that 5F-4'-thioFAC had an antitumor spectrum similar to that of 4'-thioFAC. However, 5F-4'-thioFAC was about 10 times less active than 4'-thioFAC.

Anti-herpesvirus activity profile of 4'-thioarabinofuranosyl purine and uracil nucleosides and activity of 1-beta-D-2'-fluoro-4'-thioarabinofuranosyl guanine and 2,6-diaminopurine against clinical isolates of human cytomegalovirus.

Newly synthesized 4'-thio- and 2'-fluoro-4'-thioarabinofuranosyl purine and pyrimidine nucleosides were compared with the corresponding 4'-oxo type arabinosyl nucleosides for anti-herpesvirus and anti-cell proliferative potencies. 4'-Thioarabinosyl- and 2'-fluoro-4'-thioarabinofuranosyl 5-substituted uracils had selective antiviral activities, but were not superior to 4'-oxo nucleosides, except for the activity of 5-ethyl-uracil 4'-thio nucleosides against herpes simplex virus. Furthermore, 4'-thio substituted derivatives of sorivudine (BV-araU) and related compounds, and 2'-fluoro-5-methyl-arabinosyluracil exhibited reduced activity against varicella-zoster virus compared with the parent compounds. The 4'-thioarabinosyluracils, except for 5-methyluracil derivatives, were inactive against human cytomegalovirus (HCMV). 4'-Thioarabinofuranosyl guanine and diaminopurine had the most potent anti-HCMV and anti-proliferative activities, whereas arabinosyl guanine and diaminopurine had only marginal antiviral activity. 2'-Fluoro-4'-thioarabinofuranosyl derivatives of guanine (4'-thio-FaraG) and 2,6-diaminopurine (4'-thio-FaraDAP), however, had particularly high activity against all herpesviruses tested with anti-proliferative activity equipotent to that of arabinosyl guanine and diaminopurine. 4'-Thio- and 2'-fluoro-4'-thioarabinofuranosyladenines exhibited biological activities similar to that of arabinosyladenine. Both 4'-thio-FaraG and 4'-thio-FaraDAP had a 6-fold lower ED50 than ganciclovir against clinical isolates of HCMV. A ganciclovir-resistant isolate, obtained from a patient who had received long-term ganciclovir-treatment, was susceptible to 4'-thio-FaraG and 4'-thio-FaraDAP.

Synthesis and antiviral activities of 5-substituted 1-(2-deoxy-2-C-methylene-4-thio-beta-D-ertythro-pentofuranosyl)uracils.

Various 5-substituted 1-(2-deoxy-2-C-methylene-4-thio-beta-D-erythro-pentofuranosyl)uracils (4'-thioDMDUs) were synthesized from D-glucose via sila-Pummerer-type glycosylation. All of the beta-anomers of 5-substituted 4'-thioDMDU, except the 5-hydroxyethyl derivative, showed potent anti-HSV-1 activity (ED50 = 0.016-0.096 microgram/mL). 5-Ethyl- and 5-iodo-4'-thioDMDUs were also active against HSV-2 (ED50 = 0.17 and 0.86 microgram/mL, respectively). 5-Bromovinyl-4'-thioDMDU was particularly active against VZV (ED50 = 0.013 microgram/mL).

RD6-2198, a novel betain-type fluoroalkylated oligomer, inhibits the replications of human immunodeficiency virus type 1 and other enveloped viruses.

We have examined a novel betain-type fluoroalkylated oligomer, RD6-2198, for its inhibitory effects on the replication of human immunodeficiency virus type 1 (HIV-1) and other enveloped viruses, including herpes simplex virus types 1 and 2 (HSV-1 and HSV-2, respectively) and respiratory syncytial virus (RSV) in cell cultures. We have found that the compound is a potent and selective inhibitor of these viruses. RD6-2198 inhibited the replication of HIV-1IIIB at a concentration of 0.85 microg/ml with a selectivity index greater than 59 in MT-4 cells. Furthermore, its 50% effective concentration (EC50) values for HSV-1, HSV-2 and RSV, were 0.51, 0.94 and 3.0 microg/ml, respectively. We found that the RD6-2198 suppressed the gp120-CD4 interaction (as monitored by an enzyme-linked immunosorbent assay (ELISA) method). RD6-2198 also inhibited the binding of anti-gp120 monoclonal antibody to gp120 expressed on MOLT-4/IIIB cells (MOLT-4 cells chronically infected with HIV-1IIIB). However, the compound did not inhibit the interaction of anti-CD4 antibody with CD4. These results suggest that RD6-2198 interacts with the viral envelope glycoprotein and thereby inhibits the viral adsorption process. In addition, RD6-2198 was also found to suppress the proliferation of MOLT-4/IIIB cells. When applied topically, RD6-2198 at a concentration of 10 mg/ml completely protected mice from an intravaginal HSV-2 infection.

New guiding catheter for transrad PTCA.

A new guiding catheter for PTCA is described. In our department, 302 patients (405 lesions) underwent transradial coronary angioplasty using the 6 Fr Kimny guiding catheter since January 1996. The total engagement rate using the Kimny guiding catheter was 91.3% (370/405). The engagement rate after the modified Kimny guiding catheter was introduced in May 1996 increased to 96.0% (243/253). The stent delivery success rate was 98.4%. We had two dislodged stents. PTCA for both left and right coronary arteries in a single procedure with the Kimny guiding catheter was performed via the radial artery in 27 patients. In 24 of these patients (89%) we engaged both coronaries successfully. In the remaining 3 patients we switched to another catheter. Except for 4 patients with non-Q-wave myocardial infarction, no major cardiac complications were encountered. No major entry site-related complications were seen, and no patient required vascular surgery or blood transfusions. In one patient the Kimny guiding catheter tip caused a minor dissection of the LMT, but no ischemic event occurred as a result. In conclusion, the Kimny device is a useful PTCA guiding catheter for routine angioplasty and stenting.

Enzymatic synthesis of 2'-O-acyl prodrugs of 1-(beta-D-arabinofuranosyl)-5(E)-(2-bromovinyl)uracil and of 2'-O-acyl-araU, -araC and -araA.

Pig liver esterase (EC 3.1.1.1) catalysed regioselective hydrolysis of 1-(2,3,5-tri-O-acyl-beta-D-arabinofuranosyl)uracil, -cytosine and -adenine to give the corresponding 2'-monoesters effectively and in high yield. This methodology enabled the preparation of 1-(2-O-acyl-beta-D-arabinofuranosyl)-5-[(E)-(2-bromovinyl)]uracil prodrugs which, although slightly less active than the parent 1-(beta-D-arabinofuranosyl)-5-(E)-(2 bromovinyl)uracil (sorivudine; BV-araU), were strongly active in vitro against varicella-zoster virus (ED50 2.4-45 ng/ml). The retarded rates of enzymatic hydrolysis of the 2'-esters imply that they might function as lipophilic prodrugs, leading to increased plasma and cellular concentrations. In view of the marked in vitro activity, they represent an interesting approach to arabinofuranosyl nucleoside prodrugs with improved pharmacokinetics and enzymatic stability.

Evaluation of highly sensitive thyrotropin assay for detecting thyroid diseases in neonatal screening: preliminary studies.

TSH concentrations in dried blood samples on filter paper were determined by a conventional enzyme-linked immunosorbent assay (ELISA), used for routine neonatal screening for primary hypothyroidism, and a highly sensitive bioluminescence ELISA (BL-ELISA) using firefly luciferase to examine whether central hypothyroidism and hyperthyroidism can be efficiently detected as cases of primary hypothyroidism. Samples were obtained from 3 patients with congenital central hypothyroidism, 5 patients with congenital primary hypothyroidism, 6 patients with hyperthyroidism, 31 neonatal babies with low birth weight (premature babies) and 242 newborn babies with normal birth weight from the general population (normal babies). The TSH values were low in central hypothyroidism and hyperthyroidism. Their deviations from the mean TSH value for normal babies by the BL-ELISA method (-3.12 SD and -4.79 SD in central hypothyroidism and hyperthyroidism respectively) were greater than those by the ELISA method (-2.00 SD and -2.97 SD respectively). The TSH values were high in primary hypothyroidism and normal in premature babies while deviations were the same when BL-ELISA and ELISA were used. These findings indicate that the highly sensitive TSH assay (BL-ELISA) can be used for detecting both primary and central hypothyroidism as well as hyperthyroidism in neonatal screening.

Structure-activity relationship of the affinity of 5-substituted uracil nucleoside analogues for varicella-zoster virus thymidine kinase and their activity against varicella-zoster virus.

We investigated structure-activity relationships of 5-substituted uracil nucleoside analogues for their selective antiviral activity against varicella-zoster virus (VZV) and affinity for VZV thymidine kinase (TK). Anti-proliferative activity of the compounds was measured using human lymphoblastoid cells. Most 2'-deoxyribofuranosyluracil, arabinofuranosyluracil (araU) and 2'-deoxy-2'-fluoro-arabinofuranosyluracil derivatives showed selective anti-VZV activity as well as activity against herpes simplex virus types 1 and 2. 2'-Deoxyuridine derivatives showed higher affinity than the corresponding araU analogues. A correlation was seen between the 50% effective doses for VZV and the Ki values for VZV TK, except for 5-ethyl-2'-deoxyuridine and 5-ethyl araU that showed relatively high affinity for VZV TK without showing any activity against VZV. 5-Halogenovinyluracil nucleosides showed the highest affinity and the most potent and selective anti-VZV activity. 2'-Deoxy-2'-fluoro-arabinofuranosyluracil derivatives exhibited high anti-VZV potency though they showed relatively low affinity for VZV TK. Some 3'-deoxythymidine analogues having anti-human immunodeficiency virus activity were inactive against herpesviruses.

A facile, alternative synthesis of 4'-thioarabinonucleosides and their biological activities.

4'-Thioarabinonucleosides, which are potential antiviral agents, were synthesized from D-glucose. 1,4-Anhydro-4-thioarabitol (8), which can be derived from diacetone glucose in nine steps, was subjected to Pummerer rearrangement after protection of the hydroxyl groups to give 1-O-acetyl-4-thioarabinose (11), which was condensed with nucleobases to give 4'-thioarabinonucleosides. The 5-substituted-4'-thioaraU (6a-e) derivatives showed anti-HSV-1 activity (ED50 = 0.43-3.50 micrograms/mL). 4'-ThioaraG (6h) and 2,6-diaminopurine 4'-thioarabinonucleoside (4'-thioaraDAP, 6g) showed antiviral activity against several herpes viruses and were particularly potent against human cytomegalovirus (0.010 and 0.022 microgram/mL, respectively).