High-reliability and low-dark-current 10-Gb/s planar superlatticeavalanche photodiodes

For compact and high-sensitivity 10 Gb/s optical receiver applications, we have developed low-dark-current planar-structure InAlGaAs-InAlAs superlattice avalanche photodiodes with a Ti-implanted guard-ring. The APDs exhibited dark current as low as 0.36 μA at a gain of 10. The temperature dependence of the dark current was confirmed to be in a sufficient level for practical 10-Gb/s applications. The APDs also exhibited a quantum efficiency of 67%, a gain-bandwidth-product of 110 GHz, a top 3-dB bandwidth of 15.2 GHz, and a minimum gain for 10-GHz bandwidth of 1.6. Preliminary aging test also showed a stable dark current operation after aging of over 2200 h at 200°C. These high-reliability, low-dark-current, high-speed, and wide-dynamic-range characteristics are promising for 10-Gb/s high-sensitivity optical receiver use     

In vivo voltammetric studies of the effects of intrathecal morphine on noxious heat stimuli-induced serotonin release in the nucleus raphe magnus of anesthetized rats

MOTIVATION: The principal motivation was to design an environment for the development of image-analysis applications which would allow the integration of independent modules into one frame and make available tools for their build-up, running, management and mutual communication. RESULTS: The system was designed as modular, consisting of the core and work modules. The system core focuses on overall management and provides a library of classes for build-up of the work modules, their user interface and data communication. The work modules carry practical implementation of algorithms and data structures for the solution of a particular problem, and were implemented as dynamic-link libraries. They are mutually independent and run as individual threads, communicating with each other via a unified mechanism. The environment was designed to simplify the development and testing of new algorithms or applications. An example of implementation for the particular problem of the analysis of two-dimensional (2D) gel electrophoretograms is presented. The environment was designed for the Windows NT operating system with the use of Microsoft Foundation Class Library employing the possibilities of C++ programming language. AVAILABILITY: Available on request from the authors.     

A novel method for isolation of Chlamydia pneumoniae by treatment with trypsin or EDTA

To establish a novel method for the efficient isolation of Chlamydia pneumoniae, experiments were performed to determine the effects of EDTA or trypsin treatment of C. pneumoniae on its adsorption and inclusion body formation. Treatment of C. pneumoniae with 0.1% trypsin or 1 mM EDTA significantly increased inclusion body-forming activity from 8,000- to 10,000-fold higher than that of the control. C. pneumoniae was successfully isolated in cultured cells which were inoculated with clinical specimens after treatment with 0.1% trypsin.     

Clinicopathologic features of patients with hepatocellular carcinoma surviving >10 years after hepatic resection

BACKGROUND: This study was performed to clarify the clinicopathologic features of hepatocellular carcinoma (HCC) patients surviving >10 years after hepatic resection. METHODS: Between January 1971 and April 1987, 142 patients underwent hepatic resection. Thirty-nine patients who died of surgical morbidity (surgical mortality rate: 27.5%) were excluded from this study. Among the 103 patients who survived and were observed for >10 years after surgery, 12 patients (11.7%) survived >10 years after hepatectomy. The surviving patients were divided into 2 groups: 10-year survivors (n = 12) and nonsurvivors (n = 91). A comparative study between the two groups was made. RESULTS: Preoperative liver function tests such as the indocyanine green retention test at 15 minutes and albumin levels showed that 10-year survivors had better liver function than nonsurvivors. With regard to virus markers, 5 of 12 patients (41.7%) were positive for hepatitis B surface antigen (HBs-Ag) and the incidence of hepatitis B virus-related HCC was significantly higher than in nonsurvivors (P = 0.020). The results also showed that 4 of 12 long term survivors had hepatitis C virus (HCV) antibody and 1 patient did not have any HCV antibody or HBs-Ag. In two other patients, the HCV antibody was not measured and HBs-Ag was negative. Among four patients with the HCV antibody, the serum HCV RNA concentration, measured by branched DNA probe assay, was <0.5 in 3 patients and 1.72 in 1 patient. Therefore, the HCV RNA concentration tended to be lower in 10-year survivors. Tumor recurrence occurred in 8 of the 10-year survivors. Solitary recurrence was observed in five patients whereas multiple recurrence was observed in three patients. All five patients with solitary recurrence underwent a second resection. CONCLUSIONS: Based on the results of the current study, good liver function, HBs-Ag positivity, and a low concentration of serum HCV RNA in HCV-related HCC should be considered potentially good predictors of a long term survival.     

Long-term results of short segmental syngeneic small intestinal transplantation: comparison of jejunal and ileal grafts

A short-segment intestinal graft is favorable to reduce the rate of rejection and the incidence of graft-versus-host disease in recipients of small intestine transplantation. To determine whether a jejunal or an ileal graft is preferable with respect to intestinal morphology and function, syngeneic two-step small intestinal transplantations were performed using male Lewis rats (RT1(1)). They were divided into two groups according to the small intestine donor site (group 1 received 10 cm of jejunum; group 2 received 10 cm of ileum). There was no significant difference in the survival rate or weight gain between the two groups. Nearly all the hematologic findings, serum nutritional parameters, and results of liver function tests were normal for both groups. The only difference was that the serum total bile acid level was significantly higher in group 2. Fifty weeks after transplantation, the graft mucosa showed normal architecture, with adaptive hyperplasia of villi and crypt noted through histological study. The villus height of group 1 was 595 +/- 64 microns (control, 452 +/- 67 microns); that of group 2 was 732 +/- 53 microns (control, 217 +/- 20 microns). The crypt depth of group 1 was 228 +/- 35 microns (control, 165 +/- 24 microns); that of group 2 was 320 +/- 19 microns (control, 102 +/- 19 microns). These compensatory changes were more pronounced in group 2. The authors conclude that, on the basis of long-term functional capacity, there was no significant difference between jejunal and ileal grafts, and that both segments were suitable for transplantation. However, the ileal graft was considered to be better with respect to morphological adaptation.     

Bronchial mucoid impaction due to the monokaryotic mycelium of Schizophyllum commune

PURPOSE: A prospective trial was done to test the efficacy of antimicrobial prophylaxis in patients undergoing transurethral surgery. MATERIALS AND METHODS: A total of 75 adults with preoperatively sterile urine was randomized to receive either 400 mg. oral fleroxacin once daily or placebo as long as the catheter was in place. Urine cultures were obtained preoperatively and after removal of the catheter just before hospital discharge. Growth of 10(4)/ml. or more bacteria was considered a positive urine culture. RESULTS: Postoperative urinary tract infection rates were significantly lower in the fleroxacin group (3%) than in the placebo group (23%). Our study demonstrated the benefit of antimicrobial prophylaxis in preventing urinary tract infection after transurethral surgery, including resection of the prostate, in patients with sterile urine. CONCLUSIONS: The oral administration of 1 daily tablet of fleroxacin for the duration of catheterization is a safe, efficacious and clinically feasible regimen.     

Pre-emptive analgesia from intravenous administration of opioid: no effect with pentazocine

The influence of timing of administration of preoperative pentazocine on pain and analgesic requirements after surgery was studied in 46 patients undergoing total abdominal hysterectomy. Twenty-three patients received thiamylal 5 mg.kg-1 on induction of anesthesia, followed by pentazocine 30 mg or 60 mg before surgical incision (group A). Twenty-three control patients received pentazocine 30 mg or 60 mg, 5 min after abdominal incision (group B). The visual analogue scales for pain 24 h after operation were 6.0 cm at 30 mg dose in group A or 5.3 cm at 60 mg dose in group A and 5.7 cm at 30 mg dose in group B or 4.7 cm at 60 mg dose in group B. There were no differences in the visual analogues scales. Pentazocine consumption in the first 24 h after surgery was 67.5 mg at 30 mg dose in group A or 52.5 mg at 60 mg dose in group A and 70.9 mg at 30 mg dose in group B or 51.8 mg at 60 mg dose in group B. We conclude that postoperative pentazocine consumption and pain scores are no different when pentazocine is given before or after skin incision for abdominal hysterectomy and that there is no clinically useful pre-emptive analgesic effect with these doses of pentazocine.