40 Gbit/s electroabsorption modulators with impedance-controlled electrodes

A novel travelling-wave electroabsorption optical modulator, electrically matched for 50 /spl Omega/ loads of driving circuit drivers, was developed. The scattering parameter of electric reflection (S/sub 11/) from this modulator is less than -20 dB at 20 GHz. It can thus enable a 40 Gbit/s, 2 km SMF transmission with a 0.3 dB penalty at a 1.3 /spl mu/m wavelength.     

Evaluation of the Swedish interactive thresholding algorithm, a new thresholding algorithm, of the Humphrey Field Analyzer in glaucoma patients

The Swedish interactive thresholding algorithm (SITA) is a new thresholding algorithm that aims to obtain the visual fields of the same quality in a shorter examination time than the conventional up-and-down method. We investigated the correlation between the threshold values obtained by SITA and the conventional thresholding algorithm in 30 glaucoma patients. The results of two types of SITA, i.e., SITA accurate and SITA fast, showed a significant correlation with those of the conventional method (r = 0.855, p < 0.0001 and r = 0.833, p < 0.0001, respectively). There was no statistical relation between the mean deviation (MD) of the conventional method and the difference between MD values of the conventional method, and SITA accurate and SITA fast. The examination time of SITA accurate and SITA fast was 50% and 31% shorter, respectively, than that of the conventional method. The difference in threshold of each test point in the conventional and SITA methods was minor except in one with a deep relative defect. These results indicate that SITA can be useful for detecting glaucomatous visual field defects in a shorter time.     

Transcellular transport of benzoic acid across Caco-2 cells by a pH-dependent and carrier-mediated transport mechanism

2-Amino-3-methylimidazo[4,5-f]quinoline (IQ) and 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) are two members of a family of carcinogenic heterocyclic amines (HAs) found in cooked meats that form DNA adducts after activation to N-acetoxy derivatives. The ability of IQ- and PhIP-DNA adducts to inhibit gene expression was investigated using a human growth hormone (hGH) reporter gene in a pUC12-based mammalian expression vector under the control of either the herpes simplex virus-1 thymidine kinase promoter or the human immunodeficiency virus-1 long terminal repeat. The plasmids were treated in vitro with 0, 5, 10, or 40 microM N-hydroxy-IQ or N-hydroxy-PhIP in the presence of a 10-fold molar excess of acetic anhydride to generate the N-acetoxy derivatives in situ. The adduct levels in the plasmids were quantitated by the 32P-postlabeling method. The adducted (and control) plasmids were each transfected into repair-deficient or -proficient Chinese hamster ovary cells, and expression of hGH was measured by immunoassay of growth hormone secreted into the cell medium. The results showed that IQ- and PhIP-DNA adducts inhibited gene expression in both plasmids and that the degree of inhibition of hGH production was proportional to the levels of IQ- and PhIP-DNA adducts. The degree of inhibition, however, was independent of the promoter, despite the differences in the strengths of the two promoters to drive hGH production. Repair capacity influenced the extent of inhibition of gene expression by HA adducts since, in general, fewer adducts were needed to inhibit reporter gene expression in repair-deficient cells than in repair-proficient cells. In both cell lines, DNA adducts of PhIP appeared to be more potent in inhibiting hGH expression than adducts of IQ. Whether alteration of gene expression by HA adducts plays a role in the carcinogenicity of these compounds deserves further study.     

Proton-cotransport of pravastatin across intestinal brush-border membrane

PURPOSE: The purpose of the present study is to clarify the intestinal brush-border transport mechanism of a weak organic acid, pravastatin, an HMG-CoA reductase inhibitor. METHODS: The transport of pravastatin was studied by using intestinal brush-border membrane vesicles prepared from rabbit jejunum, and uptake by the membrane vesicles was measured using rapid filtration technique. RESULTS: The initial uptake of [14C]pravastatin was markedly increased with decreases in extravesicular pH and showed a clear overshoot phenomenon in the presence of a proton gradient (pHin/out = 7.5/5.5). A protonophore, carbonylcyanide p-trifluoromethoxyphenylhydrazone, significantly reduced the uptake of [14C]pravastatin. In addition, an ionophore for sodium, potassium and proton, nigericin, stimulated the uptake of [14C]pravastatin in the presence of a potassium gradient ([K+]in/[K+]out = 0/145 mM). On the other hand, neither the imposition of an inwardly directed sodium gradient nor an outwardly directed bicarbonate gradient stimulated the uptake of [14C]pravastatin. In the presence of a proton gradient (pHin/out = 7.5/5.5), the initial uptake of pravastatin was saturable with the apparent Kt of 15.2 +/- 3.2 mM and Jmax of 10.6 +/- 1.21 nmol/mg protein/10 sec. The uptake of pravastatin was significantly inhibited by monocarboxylic acid compounds such as acetic acid and nicotinic acid in a competitive manner but not by di- or tricarboxylic acids, or acidic amino acid. CONCLUSION: It was concluded that a pH-dependent transport of pravastatin across the brush-border membrane occurs by a proton-gradient dependent carrier-mediated mechanism rather than by simple diffusion of its unionized form.     

Effectiveness of an energy-consumption information system for residential buildings

The authors have proposed a method of reducing the energy consumption in residential buildings by providing household members with information on energy consumptions in their own houses. An on-line interactive “energy-consumption information system” that displays power consumptions of, at most, 18 different appliances, power and city-gas consumption of the whole house and room temperature, for the purpose of motivating energy-saving activities has been constructed and the effectiveness of the system investigated by installing it in 10 residential buildings. The experiment showed that energy-saving consciousness was raised and energy consumption was in fact reduced by the energy-saving activities of the household members. In this paper, the system is described in detail and the effectiveness of reducing energy-consumption of the whole house and for space heating will be discussed. Also the energy-saving activities in a certain household are shown by using load duration curves.     

Expression of the Bombyx mori beta-tubulin-encoding gene in testis

We have isolated a beta-tubulin-encoding cDNA clone of Bombyx mori from testes and determined the nucleotide sequence. Northern analyses showed that its expression is testis-specific and most active in the pupal stage.     

Identification and characterization of a major lysosomal membrane glycoprotein, LGP85/LIMP II in mouse liver

To develop a less reactogenic but equally immunogenic vaccine, this study of 91 human volunteers compared the safety and immunogenic potency of a new, cell culture-derived vaccinia virus vaccine administered intradermally and intramuscularly with the licensed vaccinia vaccine administered by scarification. Cutaneous pox lesions developed in a higher proportion of scarification vaccinees. Scarification and intradermal vaccine recipients who developed cutaneous pox lesions had more local reactions but also achieved significantly higher cell-mediated and neutralizing antibody responses than those who did not develop pox lesions. Although less reactogenic, intradermal or intramuscular administration of vaccinia vaccine without the concomitant development of a cutaneous pox lesion induced lower immune responses.     

Lumbar intervertebral disc herniation in children less than 16 years of age. Long-term follow-up study of surgically managed cases

STUDY DESIGN: In this retrospective study, the long-term clinical results of lumbar intervertebral disc herniation in children less than 16 years of age were reviewed. OBJECTIVES: To evaluate the effectiveness of surgical treatment including posterior discectomy, extraperitoneal anterolateral discectomy, and anterior interbody fusion for lumbar intervertebral disc herniation in children less than 16 years of age. SUMMARY OF BACKGROUND DATA: Although previous follow-up studies on surgically managed lumbar intervertebral disc herniation in children and adolescents generally reveal good outcomes, few reports have focused on the time course of clinical findings and the long-term results. METHODS: The outcome of subjective symptoms, clinical signs, and time-related change of the intervertebral disc space in 11 patients were evaluated with an average follow-up period of 9 years (range, 5-12 years). RESULTS: The posterior discectomy procedure relieved clinical symptoms quickly. In the case of central herniation with or without intervertebral instability, extraperitoneal anterolateral discectomy or anterior interbody fusion led to favorable long-term results. Clinical symptoms (lower back pain, leg pain) and neurologic disturbance disappeared within 3 months after surgery. Recovery of normal straight leg raising test results (tight hamstrings), however, required much more time than recovery of other symptoms. Narrowing of the intervertebral disc space progressed up to 3-6 months after discectomy, but then disc space widening occurred. CONCLUSIONS: Satisfactory long-term clinical results and early return to school life were obtained with each surgical procedure. It is important to aim toward an early return to school via surgical treatment.     

Effects of 1,25-dihydroxyvitamin D3 on tumor cell invasion to the extracellular matrix in human fibrosarcoma HT1080 cells and its correlation with laminin

We investigated the role of the active form of vitamin D, 1,25-dihydroxyvitamin D3[1,25(OH)2D3], in promoting tumor cell invasiveness through the extracellular matrix, and showed that 1,25(OH)2D3-induced reduction of laminin production by the cells was correlated with the inhibitory effect of the hormone on tumor cell invasiveness. 1,25(OH)2D3 significantly inhibited invasiveness through the matrix, type IV collagenolytic and migratory activity, but not cell attachment to the matrix in human fibrosarcoma HT1080 cells. The 1,25(OH)2D3-induced inhibition showed the same dose dependency and magnitude for invasiveness as for the effects on type IV collagenolysis and cell migration. 1,25(OH)2D3 inhibited laminin production from the cells in a dose-dependent manner. The inhibitory effects of 1,25(OH)2D3 on the invasiveness, type IV collagenolysis and cell migration appeared to parallel the hormone-induced reduction of laminin production. Antilaminin monoclonal antibody, blocking the activity of laminin in the culture medium, inhibited HT1080 cell invasiveness. In the presence of exogenous laminin, 1,25(OH)2D3-induced inhibition of invasion was not observed. These findings suggest that 1,25(OH)2D3 acts on HT1080 cells, inhibiting the expression of laminin from the cells, and that the reduced laminin expression leads to the inhibition in the type IV collagenolytic and migratory activity of the cells, and consequently, to the inhibition of invasiveness through the extracellular matrix.