Filter-free wavelength converter using Sagnac loop and delayed interferometer.

A filter-free fiber-XPM-based wavelength converter is proposed and experimentally demonstrated without conventional bandpass optical filters used to filter out the converted signal. The converter is constructed with a propagation-diversity Sagnac loop to separate a converted signal from a pump signal and a delayed interferometer to covert the XPM signal into intensity modulation. We show that 10-Gbit/s input signals are successfully converted to signals with allotted wavelengths by our proposed scheme.

Regenerative mode locking via superposition of higher-order cavity modes in composite cavity fiber lasers.

We demonstrate a new method of optical pulse generation in regeneratively mode-locked fiber ring lasers (RML-FRLs). The method is based on generating dominant longitudinal modes in the fiber ring cavity by means of a composite cavity structure and their intermode beating at the photodetector incorporated in the regenerative feedback loop. The beat signal is then used as a modulation signal to generate optical pulses in a regenerative mode-locking scheme, thereby eliminating the requirement for a high-Q rf bandpass filter in a conventional RML-FRL. Optical pulses with a repetition frequency of 3.6 GHz have been generated successfully with a supermode noise suppression of more than 48 dB and a low phase noise of -85 dBc/Hz at 10 kHz offset from the carrier frequency.

Prognostic impact of CD45 antigen expression in high-risk, childhood B-cell precursor acute lymphoblastic leukemia.

To evaluate the clinical implications of CD45 expression in acute childhood lymphoblastic leukemia (ALL), we measured the CD45 expression of blast cells from 133 untreated patients with childhood B-precursor ALL (n = 118) or T-ALL (n = 15). CD45 expression (> or = 20%) was detected in all 15 cases (100%) of T-ALL, and 101 cases (86%) of B-precursor ALL. In 122 cases, the fluorescence intensity of the CD45 expression was measured as a relative value; the ratio of average linear values (RALV) of CD45 on the blasts to that on CD3-positive T-lymphocytes from the same specimen. The expression was more intense in the T-ALL cases than in the B-precursor ALL cases (RALV, mean +/- SE: T-ALL 0.230 +/- 0.04 vs. pro-B ALL 0.150 +/- 0.012/pre-B ALL 0.153 +/- 0.019, p < 0.05). However, the intensity of the CD10, CD19, CD20 and CD34 antigen immunoreactivity did not correlate with the CD45 expression. Patients with hyperdiploidy (chromosome number > 50) showed significantly lower levels of CD45 expression than patients with t(1;19) or normal karyotypes (RALV, mean +/- SE: 0.081 +/- 0.022 vs. 0.133 +/- 0.03/0.143 +/- 0.019, p < 0.05). Other clinical features such as age, gender and WBC count did not correlate with CD45 expression. The prognostic implications of CD45 expression were studied in non-high-risk (low-risk + intermediate-risk) (n = 60) and high-risk patients (n = 52) with B-precursor ALL who had been treated with the risk-directed protocol of ALL-941 trial. Although CD45 expression did not correlate with the event-free survival (EFS) of the non-high-risk patients, there was a significant correlation between the expression levels and the EFS of the high-risk patients: the 3-year EFS rate of the CD45low group (n = 26, RALV = 0.017-0.132) was 88 +/- 7% versus the CD45high group (n = 26, RALV = 0.133-0.450) at 34 +/- 24% (p < 0.05). These results show that the levels of expression of the CD45 antigen on leukemic lymphoblasts are significantly correlated with the clinical features and prognosis of childhood ALL.

Tubulointerstitial nephritis and uveitis syndrome in two siblings.

Two Japanese sisters with persistent uveitis showed significant increased levels of urinary beta-2 microglobulin. A percutaneous renal biopsy performed in the younger sister revealed tubulointerstitial nephritis (TIN) with helper/inducer T cell infiltrates. Also, abnormal 67-gallium accumulation in the kidneys, suggesting TIN, was observed in the other one at the same time. Although patients with the syndrome of tubulointerstitial nephritis and uveitis (TINU) have been reported to date, its occurrence in siblings has rarely been seen. Both of them shared same human leukocyte antigen (HLA) DR6, suggesting the potential association between HLA-DR6 and TINU.

A bibliometric study on chemical information and computer sciences focusing on literature of JCICS.

A bibliometric approach was used to survey the state-of-the-art of research in the field of chemical information and computer sciences (CICS). By examining the CA database for the articles abstracted under the subsection "Chemical information, documentation, and data processing", Journal of Chemical Information and Computer Sciences (JCICS) was identified to have been the top journal in this subsection for the last 30 years. Based on this result, CA subsections and controlled index terms given to JCICS articles were analyzed to see trends in subjects and topics in the CICS field during the last two decades. These analyses revealed that the subjects of research in CICS have diversified from traditional information science and computer applications to chemistry to "molecular information sciences". The SCISEARCH database was used to grasp interdependency between JCICS and other key journals and also the international nature of JCICS in its publications and citedness.

Active stabilization of a higher-order mode-locked fiber laser operating at a pulse-repetition rate of 154 GHz.

We report stabilization of a higher-order mode-locked Er-fiber laser producing transform-limited 800-fs Gaussian pulses at a repetition rate of 154 GHz against variation of cavity length caused by ambient temperature fluctuation. We obtained an error signal suitable for active control of the cavity length and synchronization to a 38.4-GHz external clock by tailoring the chromatic dispersion of the ring laser cavity and using a feedback circuit based on balanced photodetection. The wavelength and the repetition rate of the stabilized laser could be tuned over ranges of 11 nm and ~100 MHz , respectively.

Fourier synthesis of 1.8-THz optical-pulse trains by phase locking of three independent semiconductor lasers.

Fourier synthesis of ultrafast optical-pulse trains was demonstrated based on optical phase locking of three independent continuous-wave semiconductor lasers. Pulse repetition frequencies as high as 1.81 THz were limited by the gain bandwidth of an erbium-doped fiber amplifier. The waveforms of the pulse trains were maintained over a long period by use of an auxiliary optical phase-locked loop. The repetition frequency could be tuned continuously over a range of 100 MHz.

Acute glomerulonephritis superimposed on focal segmental glomerulosclerosis: a case report.

A 9-year-old boy was referred to our hospital because of significant hematuria and proteinuria associated with hypocomplementemia. Although he had had a 3-year history of asymptomatic persistent proteinuria detected by urine screening of school children, he did not visit a physician. Finally, he visited a regional hospital, and hypocomplementemia was noted there. A percutaneous renal biopsy performed hospital day 4 revealed diffuse endocapillary proliferative glomerulonephritis with severe tubulointerstitial changes. Although his hematuria and hypocomplementemia spontaneously subsided within a month, proteinuria remained. A renal biopsy performed 4 months after the first renal biopsy revealed the lesion suggesting advanced focal segmental glomerulosclerosis (FSGS). Despite corticosteroid treatment, his proteinuria persisted, and he developed end stage renal failure. These clinical observation indicated that he had acute glomerulonephritis (AGN) superimposed on non-nephrotic FSGS, and that the episode of AGN might cause exacerbation of the FSGS.

Focal segmental glomerulosclerosis: unremitting proteinuria of long duration as a possible etiology?

A Japanese boy aged 9 years referred to our hospital because of steroid-resistant proteinuria. He had a 6-year history of unremitting proteinuria and was diagnosed as having minimal-change disease (MCD) by the repeated renal biopsies performed at the age of 3.5 years and 8.5 years, respectively. His proteinuria fluctuated ranging from 115 mg/100 ml to 645 mg/100 ml, and serum total protein ranged from 59 g/liter to 63 g/liter. The third renal biopsy at the presentation also revealed MCD. Thereafter he was treated with an anti-thrombocyte agent combined with an angiotensin converting enzyme inhibitor. Despite unremitting proteinuria of long duration, he did not have any complaints. At the age of 11.5 years, severe tubulointerstitial lesion was observed in the fourth renal biopsy. The fifth renal biopsy 6 months after the fourth finally revealed the lesion of focal segmental glomerulosclerosis (FSGS). Although the interpretation of his repeated renal biopsies were considered to be limited, these clinical observation suggested that his unremitting proteinuria of long duration might have been attributed to subsequent progression FSGS.

Measurement of the chromatic dispersion of an optical fiber by use of a Sagnac interferometer employing asymmetric modulation.

We describe a novel method, based on asymmetric modulation in a Sagnac interferometer, that measures the chromatic dispersion of single-mode fibers. The interferometer incorporates a phase modulator and a test fiber, so the dispersion can be determined from the interference fringe seen when a sweep rf signal is applied to the modulator. This technique provides picosecond temporal resolution without the need for any fast diagnostic equipment and is capable of accurately measuring the average dispersion of fibers several kilometers long.

The C422F mutation of the growth hormone receptor gene is not responsible for short stature.

A missense mutation, C422F, was identified in the intracellular domain of GH receptor (GHR) in a Japanese short boy. Although this mutation was previously reported in a patient with GH insensitivity syndrome (GHIS), it has not been clear whether this mutation causes GH insensitivity. To clarify the effect of this mutation on GH signal transduction, mutant GHR was expressed in CHO cells, and its functional properties were investigated. There were no significant differences in GH-induced tyrosine phosphorylation of STAT5b (signal transducer and activator of transcription) between wild-type GHR (GHR-wt)- and mutant GHR (GHR-C422F)-expressing cells. Moreover, STAT5-mediated transcriptional activation of GHR-C422F-expressing cells was comparable to that of GHR-wt-expressing cells. These findings indicated that the C422F mutation of GHR affected neither GH-induced tyrosine phosphorylation nor the transcriptional activation of STAT5. In addition, the analysis of genotypes and phenotypes of his family revealed that body heights of family members with heterozygous or homozygous C422F mutations were all within normal ranges, with the single exception of the proband. These in vitro and in vivo results indicate that the C422F missense mutation of GHR is a polymorphism that does not result in GHIS.

Glomerulonephritis without IgA deposits in a case of Henoch-Schönlein purpura.

A boy aged 3 years 8 months with Henoch-Schönlein purpura (HSP) developed significant proteinuria with hematuria 2 days after the appearance of purpura rash. Although thought to be purpura nephritis, a percutaneous renal biopsy revealed diffuse mesangial proliferative glomerulonephritis (MesPGN) without deposition of immunoglobulin A or complement. Since his urine screening test during a health check at the age of 3.5 years had been unremarkable, HSP might have played a role in the pathogenesis of his non-IgA MesPGN. To our knowledge, non-IgA MesPGN is an uncommon renal manifestation of HSP.

Long-term azathioprine therapy in two children with steroid-dependent minimal-change nephrotic syndrome.

Long-term azathioprine therapy as an alternative treatment to cyclophosphamide was done in 2 children with steroid-dependent minimal-change nephrotic syndrome (MCNS). They had already been treated with prednisolone, intravenous methyl-prednisolone pulse therapy, cyclophosphamide and mizoribine. Although cyclophosphamide had been proved to be effective in maintaining their remission, the cumulative dose of the agent limited another course of cyclophosphamide therapy. Since ciclosporine therapy is much expensive, a trial of azathioprine (2 mg/kg per day) was started, and the therapy resulted in inducing sustained remission and reducing prednisolone. The patients were well tolerated the long-term azathioprine therapy over a year. Although the efficacy of azathioprine in the management of childhood MCNS might be restricted, we therefore suggest that this agent should be reconsidered as an alternative treatment to cyclophosphamide.

Internal tandem duplication of the FLT3 gene and clinical evaluation in childhood acute myeloid leukemia. The Children's Cancer and Leukemia Study Group, Japan.

We analyzed tandem duplication in the juxtamembrane (JM) domain of the FLT3 (FMS-like tyrosine kinase 3/FLK2, CD135) gene in 94 children with acute myeloid leukemia (AML) and evaluated its correlation with clinical features. Longer polymerase chain reaction (PCR) products were observed in five patients; 1/3 of M0, 119 of M1, 1/39 of M2, 1/9 of M3 and 1/12 of M5. The sequence analyses of abnormal PCR products showed that all the abnormal products were derived from tandem duplications involving the JM domain and that all the lengthened sequences were in-frame as we previously reported. Statistical analyses revealed a significantly lower incidence of the tandem duplication in childhood AML patients than in adult patients (P < 0.05), and significantly shorter disease-free survival in patients with mutant FLT3 than in patients with wild-type FLT3 (P < 0.05). Our results suggest that the tandem duplication in the JM domain of the FLT3 gene is not a frequent phenomenon but might be a factor of poor prognosis in childhood patients with AML.

Fourier synthesis of 9.6-GHz optical-pulse trains by phase locking of three continuous-wave semiconductor lasers.

Fourier synthesis of optical-pulse trains based on optical phase locking of three cw semiconductor lasers has been demonstrated by use of a semiconductor optical amplifier as a four-wave mixer. The temporal waveforms of the pulse trains were directly observed at a repetition rate of 9.6 GHz by a fast sampling oscilloscope. The FM sideband heterodyne technique was employed to realize a stable homodyne optical phase-locked loop.

Generation of a 64-GHz, 3.3-ps transform-limited pulse train from a fiber laser employing higher-order frequency-modulated mode locking.

We demonstrate the generation of optical pulses at a repetition rate of 64 GHz directly from a frequency-modulated (FM) mode-locked fiber laser. This is achieved by phase modulation at 16 GHz and by initiating of higher-order FM mode locking by use of an intracavity Fabry-Perot filter with a free spectral range of 64 GHz. This process yielded transform-limited pulses with a width of 3.3 ps. We investigated the operating characteristics of the laser and compared them with the characteristics that were predicted theoretically.

Effects of soy milk and bifidobacterium fermented soy milk on lipid metabolism in aged ovariectomized rats.

The effects of soy milk and fermented soy milk on lipid metabolism were studied in aged ovariectomized rats. Twenty 8-mo-old Wistar rats were randomly assigned to four treatment groups: sham-operated + control diet (sham-C); ovariectomized (OVX) + control diet (OVX-C); OVX + soy milk diet (OVX-SM); and OVX + fermented soy milk diet (OVX-FSM). The rats were fed on these diets for 6 weeks. Ovariectomy induced an increase in the plasma cholesterol level by 40%. The plasma total cholesterol level of the OVX-FSM rats was decreased by 20% compared to that of the OVX-C rats. The plasma total cholesterol level of the OVX-SM group was not significantly different from that of the OVX-C and sham-C rats. The plasma triglyceride level of the OVX-FSM rats was lower than that of the sham-C rats. The liver cholesterol content in OVX-SM and OVX-FSM rats was lower than that of the OVX-C rats. The liver triglyceride contents of the sham-C, OVX-SM, and OVX-FSM groups were lower than that of the OVX-C group. Fecal steroid excretion did not differ among the groups. Ovariectomy decreased the uterus weight. The OVX-SM and OVX-FSM groups had the same uterus weights as those of the OVX-C group. Thus, the diet including fermented soy milk prevented the cholesterol elevation induced in rats by ovarian hormone deficiency.

An infant case of bilateral small kidneys with both proximal and distal tubular dysfunction.

A male infant with bilateral small kidneys associated with both proximal and distal tubular dysfunction, who showed chronic renal failure soon after birth, is reported. He was also noted to have both proximal and distal type of renal tubular acidosis. The small kidneys were thought to be due to renal hypodysplasia associated with bilateral severe vesicoureteral reflux, by radiological findings. An alkalization therapy with chemoprophylaxis seemed to be of benefit in slowing the progression of renal failure in this case.