Pharmacokinetics and disposition of CS-8958, a long-acting prodrug of the novel neuraminidase inhibitor laninamivir in rats

CS-8958, a prodrug of laninamivir (R-125489), is currently under development as an inhaled anti-influenza drug. In this study, the pharmacokinetics and disposition of CS-8958 were characterized in rats. After intratracheal administration of 14C-CS-8958, radioactivity was retained over long periods in the target tissues (trachea and lung) as its active metabolite R-125489 - 19.12% of the dose was retained in the lung at 24 h. After intratracheal administration of CS-8958, plasma R-125489 concentration was slowly eliminated, and its half-life (14.1 h) was considerably longer than that after intravenous administration of R-125489. The radioactivity of intratracheally administered 14C-CS-8958 was mainly excreted into the urine (67.5% of dose), and this excretion lasted over long periods. R-125489 accounted for most of the urinary radioactivity recovered after 24 h. These results demonstrated that CS-8958 administered intratracheally to rats was converted/hydrolysed to R-125489 in the target tissues, and that the R-125489 was slowly excreted into the urine via an absorption rate-limiting process. Such distinctive pharmacokinetics attributed to the slow release of R-125489 suggests the potential for a long-acting anti-influenza drug.

Effect of pressure on lattice distortion, transport and magnetic properties of Pr-substituted La(1.2)Sr(1.8)Mn(2)O(7) bilayered manganite

We have studied the effect of pressure on the anomalous lattice striction, both in the ab-plane and along the c-axis, of (La,Pr)(1.2)Sr(1.8)Mn(2)O(7) single crystals over the temperature region where the paramagnetic insulator to ferromagnetic metal transition takes place. We have examined the temperature dependence of the resistivity and the magnetization under applied pressure. The chemical pressure effect due to Pr-substitution at the La site suppresses the transition temperature of the parent crystal, while the application of external pressure on Pr-substituted crystals enhances the double exchange driven metallic state, resulting in a stable rise of T(c).

Prevalence of adult-onset multifactorial disease among offspring of atomic bomb survivors

The first study to examine whether parental radiation exposure leads to increased heritable risk of common adult-onset multifactorial diseases (i.e., hypertension, diabetes mellitus, hypercholesterolemia, ischemic heart disease, and stroke) was conducted among 11,951 participants in the clinical examination program out of a potential of 24,673 mail survey subjects who were offspring of survivors born from May 1946 through December 1984. Logistic regression analyses demonstrated no evidence of an association between the prevalence of multifactorial diseases in the offspring and parental radiation exposure, after adjusting for age, city, gender and various risk factors. The odds ratio (OR) for a paternal dose of 1 Gy was 0.91 [95% confidence interval (CI) 0.81-1.01, P = 0.08], and that for a maternal dose of 1 Gy was 0.98 (95% CI 0.86-1.10, P = 0.71). There was no apparent effect of parental age at exposure or of elapsed time between parental exposure and birth, but male offspring had a low odds ratio (OR = 0.76 at 1 Gy) for paternal exposure, but cautious interpretation is needed for this finding. The clinical assessment of nearly 12,000 offspring of A-bomb survivors who have reached a median age of about 50 years provided no evidence for an increased prevalence of adult-onset multifactorial diseases in relation to parental radiation exposure.

Unusually small electrical resistance of three-dimensional nanoporous gold in external magnetic fields

We report the electric conductivity of three-dimensional (3D) nanoporous gold at low temperatures and in strong magnetic fields. It was found that topologically disordered 3D nanoporosity leads to extremely low magnetoresistance and anomalous temperature dependence as the characteristic length of nanoporous gold is tuned to be approximately 14 nm. This study underscores the importance of 3D topology of a nanostructure on electronic transport properties and has implications in manipulating electron transport by tailoring 3D nanostructures.

Absolute calibration of an electron spectrometer using high energy electrons produced by the laser-plasma interaction

An in situ observation system has been developed to observe the absolute electron energy spectra of electron beams generated by laser-plasma interaction. A phosphor screen (DRZ) coupled with a charge coupled device camera is used to detect the electrons. A new method is proposed to calibrate the absolute sensitivity of the detection system for a wide energy range with a single shot by using an electron beam generated by laser-plasma interaction. The sensitivity of the system is found to be high, which is comparable to that of an imaging plate.

Monitoring of chemotherapy response in malignant pleural mesothelioma using fluorodeoxyglucose positron emission tomography

We report a 56-year-old man who underwent monitoring of the response to chemotherapy of malignant pleural mesothelioma (MPM). (8)F-fluoro-2-deoxy-(D)-glucose positron emission tomography (FDG-PET) and computed tomography (CT) were performed prior to chemotherapy and after the first and second courses of chemotherapy. The tumor lesion exhibited shrinkage on CT and a decrease in the standardized uptake value (SUV) max after the first course of chemotherapy, but exhibited size enlargement and an increase in SUV max after the second course of chemotherapy. These findings suggest that results of quantification of metabolic response by FDG-PET are related to the objective response as determined by CT in patients with MPM.

Dendritic cells have a crucial role in the production of cytokines in mesenteric lymph nodes of B10.BR mice infected with Trichuris muris

Dendritic cells bridge innate and adaptive immunity and establish protective immunity to pathogens. Protection against the murine nematode parasite Trichuris muris depends on the T helper 2 (Th2) response and requires the Th2 cytokines interleukin 4 (IL-4), IL-10, or IL-13. To examine if the Th2 response to T. muris infection is regulated by CD11c(+)B220(-) dendritic cells in mesenteric lymph nodes, dendritic cell-enriched and dendritic cell-depleted fractions were obtained from mesenteric lymph node cells of T. muris-infected mice, and production of cytokines in cultures of these fractions was measured. At day 14 postinfection, no worm expulsion was observed, and high levels of interferon gamma production occurred in dendritic cell-enriched fractions. Expulsion of worms occurred on days 20 and 25 postinfection, and IL-10 production was induced in dendritic cell-enriched fractions on these 2 days. No cytokine production was observed in mesenteric lymph node cells and dendritic cell-depleted fractions during T. muris infection. The occurrence of worm expulsion was consistent with IL-10 production in dendritic cell-enriched fractions. IL-10 inhibits Th1 cells and promotes the Th2 response, and results from this study suggest that CD11c(+)B220(-) dendritic cells in the mesenteric lymph nodes are required for IL-10 production and the IL-10-dependent protective Th2 response.

Steplike lattice deformation of single crystalline (La0.4Pr0.6)1.2Sr1.8Mn2O7 bilayered manganite

We report a steplike lattice transformation of single crystalline (La0.4Pr0.6)1.2Sr1.8Mn2O7 bilayered manganite accompanied by both magnetization and magnetoresistive jumps, and examine the ultrasharp nature of the field-induced first-order transition from a paramagnetic insulator to a ferromagnetic metal phase accompanied by a huge decrease in resistance. Our findings support that the abrupt magnetostriction is closely related to an orbital frustration existing in the inhomogeneous paramagnetic insulating phase rather than a martensitic scenario between competing two phases.

Usefulness of F-18 FDG-PET in a long-term hemodialysis patient with renal cell carcinoma and pheochromocytoma

A patient who had been on long-term hemodialysis (HD) was diagnosed as having renal cell carcinoma (RCC) and pheochromocytoma. Abdominal computed tomography scanning demonstrated a right renal mass and a right adrenal mass, whereas positron emission tomography (PET) using F-18 fluorodeoxyglucose (FDG) revealed increased accumulation in both the renal and adrenal masses. FDG-PET is useful for detecting RCC in HD patients because FDG is not excreted in the urine, but it is difficult to distinguish pheochromocytoma from an adrenal metastasis by this imaging method.

Comparison of dynamic FDG-microPET study in a rabbit turpentine-induced inflammatory model and in a rabbit VX2 tumor model

PURPOSE

We investigated the optimum time for the differentiation tumor from inflammation using dynamic FDG-microPET scans obtained by a MicroPET P4 scanner in animal models.

MATERIALS AND METHODS

Forty-six rabbits with 92 inflammatory lesions that were induced 2, 5, 7, 14, 30 and 60 days after 0.2 ml (Group 1) or 1.0 ml (Group 2) of turpentine oil injection were used as inflammatory models. Five rabbits with 10 VX2 tumors were used as the tumor model. Helical CT scans were performed before the PET studies. In the PET study, after 4 hours fasting, and following transmission scans and dynamic emission data acquisitions were performed until 2 hours after intravenous FDG injection. Images were reconstructed every 10 minutes using a filtered-back projection method. PET images were analyzed visually referring to CT images. For quantitative analysis, the inflammation-to-muscle (I/M) ratio and tumor-to-muscle (T/M) ratio were calculated after regions of interest were set in tumors and muscles referring to CT images and the time-I/M ratio and time-T/M ratio curves (TRCs) were prepared to show the change over time in these ratios. The histological appearance of both inflammatory lesions and tumor lesions were examined and compared with the CT and FDG-microPET images.

RESULTS

In visual and quantitative analysis, All the I/M ratios and the T/M ratios increased over time except that Day 60 of Group 1 showed an almost flat curve. The TRC of the T/M ratio showed a linear increasing curve over time, while that of the I/M ratios showed a parabolic increasing over time at the most. FDG uptake in the inflammatory lesions reflected the histological findings. For differentiating tumors from inflammatory lesions with the early image acquired at 40 min for dual-time imaging, the delayed image must be acquired 30 min after the early image, while imaging at 90 min or later after intravenous FDG injection was necessary in single-time-point imaging.

CONCLUSION

Our results suggest the possibility of shortening the overall testing time in clinical practice by adopting dual-time-point imaging rather than single-time-point imaging.

Biochemical property and immunogenicity of mouse male reproductive tract CD52 (mrt-CD52)

Male reproductive tract CD52 (mrt-CD52) is known to be a pathogenic antigen for immunological infertility. Although human CD52 has been extensively investigated, the properties of mouse CD52 are not well elucidated. This study was conducted, therefore, to examine the tissue distribution, molecular composition and immunogenicity of mouse mrt-CD52. Immunohistological studies with an antibody to a synthetic peptide showed that mouse CD52 was localized mainly in the cauda epididymis and vas deferens, but not in the testis, liver, kidney or spleen. The molecule was composed of Asn (N)-linked and The/Ser (O)-linked carbohydrates as well as a glycosylphosphatidyl (GPI) anchor portion. Purified mrt-CD52 preparations produced antibodies by subcutaneous and intranasal immunization in both male and female mice. These antisera showed sperm-immobilizing activities with complement to mouse sperm. The research indicated mouse CD52 had similar biochemical and immunological properties to human CD52. This animal experiment is a good model for investigating human mrt-CD52 antibody detected in infertile patients.

Highly sensitive detection of HPV-DNA in paraffin sections of human oral carcinomas

BACKGROUND

Although human papillomavirus (HPV) infection has been shown to be a significant carcinogen in cervical squamous cell carcinoma (SCC), its significance in oral SCC remains unclear.

METHODS

We developed highly sensitive detection methods for HPV to elucidate the prevalence and localization of HPV in paraffin sections from human oral SCC using modified in situ polymerase chain reaction (PCR) and in situ hybridization AT tailing (ISH-AT). Analyses revealed a high prevalence of several HPV types (HPV-16, -18, -22, -38 and -70) under optimal conditions. The ISH-AT method can be used as an alternative to in situ PCR.

RESULTS

Various staining patterns were observed in the 20 cases examined, and HPV-positive cells were localized within the surface epithelium as well as in neoplastic cells. We demonstrated that HPV-DNA could be detected in paraffin sections using either the method of in situ PCR or ISH, providing an appropriate primer and probe are used.

CONCLUSION

These results suggest that HPV infection could be one of several risk factors being involved in oral SCC.

Subpial schwannoma of the cervical spinal cord mimicking an intramedullary tumor

We report a rare case of a subpial schwannoma of the cervical cord mimicking an intramedullary tumor in a 65-year-old woman. The magnetic resonance imaging findings are presented and discussed.

Large-Scale Synthesis of Immunoactivating Natural Product, Pristane, by Continuous Microfluidic Dehydration as the Key Step

An efficient protocol of dehydration was developed under microfluidic conditions. The method was applied to a multikilogram synthesis of pristane, a biologically important natural product, which is now widely used as an adjuvant for monoclonal antibody production. [reaction: see text].