Population pharmacokinetic analysis of meropenem in Japanese adult patients.

WHAT IS KNOWN AND OBJECTIVE: Meropenem is frequently employed as an empirical treatment for serious infections, but there has been no report on its population pharmacokinetic parameters for Japanese patients. Our aim is to undertake a population pharmacokinetic analysis of meropenem using non-linear mixed effects model (NONMEM). METHODS: Data from 68 patients were analysed via NONMEM with the first-order method. The participants' covariates, including gender, age, actual body weight, serum creatinine, serum albumin, serum total protein and creatinine clearance, were analyzed by the forward inclusion and backward elimination method to identify their potential influence on meropenem pharmacokinetics. The adequacy of the constructed model was assessed by goodness-of-fit plots and the precision of the parameter estimated at each step of the model development. To assess the robustness of the estimated parameter, bootstrap analysis was performed. RESULTS AND DISCUSSION: The data were best described by a one-compartment model. The serum creatinine values modified by the below normal limit in our hospital (mSCR) were an influential covariate for clearance (CL): CL (L/h) = 11·1 × (mSCR/0·7)(-1). The volume of distribution was estimated as 33·6 L. The coefficient of variation of the inter-individual variability of CL and the residual variability were 52·1% and 0·827% µg/mL, respectively. A comparison of the population pharmacokinetic parameters of meropenem in the final model estimated in NONMEM with original data, and 1000 bootstrap samples shows that both sets of estimates were comparable, thereby indicating the robustness of the proposed model. WHAT IS NEW AND CONCLUSION: A population pharmacokinetic model that satisfactorily described the disposition and variability of meropenem in our Japanese population is described. NONMEM analysis showed that the clearance of meropenem depended on modified serum creatinine. The results of this study should help Japanese patients on meropenem by improving the prediction accuracy of dosing using the Bayesian method.

Allogeneic intra-BM-BMT plus adult thymus transplantation from same donor has benefits for long-term survival even after sublethal irradiation or low-dose BM cell injection.

We examined the effects of intra-BM-BMT (IBM-BMT) plus adult thymus transplantation (ATT) from the same donor after 5.5 Gy sublethal irradiation (SubLI) or low-dose (3 x 10(6)) BM cell injection (LDBMCI). With SubLI, BALB/c mice that had received 1 x 10(7) bone marrow cells by IBM-BMT plus ATT from B6 mice showed 73% donor chimerism, whereas those treated with IBM-BMT alone showed 45% chimerism. In the LDBMCI with 7Gy irradiation, IBM-BMT plus ATT resulted in a 90% survival rate with 90% chimerism, whereas IBM-BMT alone resulted in a 55% survival rate with 44% chimerism. Although the number of CD4 T cells was higher in IBM-BMT plus ATT than in IBM-BMT alone, the percentages of FoxP3+/CD4+ T cells and lymphocyte functions in the former were almost identical to those in the latter. When treated with IBM-BMT plus donor lymphocyte infusion (DLI), the mice showed a reduced survival time as a result of GVHD, with low numbers of FoxP3+CD4 T cells under either condition, although 100% chimerism was induced. These results suggest that IBM-BMT plus ATT is effective in reconstituting the recipients with donor-derived cells even after SubLI or LDBMCI.

Prevention of graft-versus-host disease by intrabone marrow injection of donor T cells: involvement of bone marrow stromal cells.

We have developed a new and effective method for bone marrow transplantation (BMT): bone marrow cells (BMCs) are injected directly into the bone marrow (BM) cavity of recipient mice. The intrabone marrow injection of BMCs (IBM-BMT) greatly facilitates the engraftment of donor-derived cells, and IBM-BMT can attenuate graft-versus-host reaction (GVHR), in contrast to conventional intravenous BMT (i.v.-BMT). Here, we examine the mechanisms underlying the inhibitory effects of IBM-BMT on GVHR using animal models where GVHR is elicited. Recipient mice (C57BL/6) were irradiated and splenic T cells (as donor lymphocyte infusion: DLI) from major histocompatibility complex-disparate donors (BALB/c) were injected directly into the BM cavity (IBM-DLI) or injected intravenously (i.v.-DLI) along with IBM-BMT. The BM stromal cells (BMSCs) from these recipients were collected and related cytokines were examined. The recipient mice that had been treated with IBM-BMT + i.v.-DLI showed severe graft-versus-host disease (GVHD), in contrast to those treated with IBM-BMT + IBM-DLI. The suppressive activity of BMSCs in this GVHD model was determined. The cultured BMSCs from the recipients treated with IBM-BMT + IBM-DLI suppressed the proliferation of responder T cells remarkably when compared with those from the recipients of IBM-BMT + i.v.-DLI in mixed leucocyte reaction. Furthermore, the level of transforming growth factor-beta and hepatocyte growth factor in cultured BMSCs from IBM-BMT + IBM-DLI increased significantly when compared with those from the recipients of IBM-BMT + i.v.-DLI. Thus, the prevention of GVHD observed in the recipients of IBM-BMT + IBM-DLI was attributable to the increased production of immunosuppressive cytokines from BMSCs after interaction with host reactive T cells (in DLI).

Transplantation of newborn thymus plus hematopoietic stem cells can rescue supralethally irradiated mice.

We attempted to rescue supralethally irradiated (SLI) mice by transplantation of hematopoietic stem cells (HSCs) plus thymus from variously aged donors (fetus, newborn and adult). Although the transplantations of these kinds of HSCs alone showed a very short survival, newborn liver cells (NLCs) (as the source of HSCs) plus newborn thymus (NT) transplantation markedly improved the survival rate. The transplantation attenuated severe damage in the small intestine, which is one of the major causes of death by SLI. In addition, the donor-derived CD4(+) T cells significantly increased with additional NT transplantation. The production of interleukin (IL)-7 and keratinocyte growth factor, which plays a crucial role in protection against radiation injury in the intestine, was the highest in NT. Finally, SLI mice that had received NLC plus IL-7(-/-) NT transplantation plus IL-7 injection showed improved survival, weight recovery and an elevated number of CD4(+) T cells compared with the mice that had received NLC plus IL-7(-/-) NT or plus IL-7 injection alone. These findings suggest that NLCs plus NT transplantation can rescue SLI mice most effectively, and that high production of IL-7 in NT plays a crucial role with induction of CD4(+) T cells.

Treatment of autoimmune diseases in MRL/lpr mice by allogenic bone marrow transplantation plus adult thymus transplantation.

MRL/lpr mice (H-2(k)) with Fas gene mutation develop severe autoimmune diseases, and their haematolymphoid cells such as bone marrow and spleen cells showed a low apoptotic activity by irradiation. Therefore, conventional bone marrow transplantation (BMT) cannot be used to treat autoimmune diseases in these mice (chimeric resistance). In the present study, we examine the effects of additional adult thymus transplantation (TT) from the same donor on successful BMT. When the MRL/lpr mice were lethally irradiated (9 x 5Gy) and reconstituted with 3 x 10(7) of C57BL/6 mouse (H-2b) bone marrow cells (BMCs) in conjunction with TT, the mice significantly survived long term and showed a high donor-derived chimerism in comparison with those treated with BMT alone. Interestingly, the numbers of not only donor-derived T cells but also B cells increased significantly in the mice treated with BMT plus TT, even at the early phase of BMT. The number of aberrant CD3+B220+ cells decreased significantly, and the numbers of lymphocyte subsets were also normalized 4 weeks after the treatment. Finally, the autoimmune diseases in MRL/lpr mice could be cured by BMT with TT. These results indicate that the combination of BMT plus TT can overcome the chimeric resistance and treat the autoimmune diseases in MRL/lpr mice.

Relationship of p53, Bcl-2, Ki-67 index and E-cadherin expression in early invasive breast cancers with comedonecrosis as an accelerated apoptosis.

AIMS: To study the relationship between comedonecrosis formation and morphology, apoptosis, and p53, Bcl-2, Ki-67 index and E-cadherin expression in early invasive breast cancer. EXPERIMENTAL DESIGN: Early invasive breast cancers were first divided into two groups according to the presence (CN+ tumours) or absence (CN- tumours) of comedonecrosis. The histological grade, apoptosis, and expression of E-cadherin, Ki-67, p53 and Bcl-2 in the cancer-affected area, and in normal ducts from the specimen, were then examined. RESULTS: Less tubule and gland formation was seen in CN+ tumours than in CN- tumours, although the histological grade between the groups was not different. During early comedonecrosis, cells undergo apoptosis and subsequent necrosis. p53 was higher in CN+ tumours than in CN- tumours and normal ducts, whereas Bcl-2 was lower in CN+ tumours than in CN- tumours and normal ducts. Both tumours had higher Ki-67 than in normal ducts, but no difference was evident between the tumours. CN+ tumours had slightly higher E-cadherin than that in CN- tumours, but lower than that in normal ducts. The level of comedonecrosis was positively correlated with p53, but inversely correlated with Bcl-2 in all tumours, and p53 and Bcl-2 were inversely correlated with each other. Furthermore, comedonecrosis and p53 were correlated with Ki-67 in CN+ tumours, and Bcl-2 was correlated with Ki-67 in CN- tumours. CONCLUSION: Comedonecrosis may be actively regulated through an apoptotic procedure in massive cancers for their survival and progression, and the above proteins may be associated cooperatively in this process. CN+ and CN- tumours may have opposite proliferative systems under the p53-Bcl-2 pathway.

[Clinicopathologic study of thymic epithelial tumors].

OBJECTIVE: We analyzed clinicopathologic characters and long-term results of 11 thymic epithelial tumors. METHODS: Five cases of thymic carcinoma and 6 cases of thymoma treated in our hospital from September 1991 to June 2002 were retrospectively analyzed. RESULTS: The histological subtypes of thymic carcinoma were basaloid carcinoma in 2 cases, epidermoid non-keratinizing carcinoma in 1 case, undifferentiated carcinoma in 1 case and sarcomatoid carcinoma in 1 case. Four cases underwent chemotherapy and radiotherapy. Three cases underwent midsternal thoracotomy, 1 had total resection and 2 had exploratory thoracotomy due to tumor invasion of the right upper lobe and cardiac sac. Two cases of basaloid carcinoma had been alive more than 10 years since the operation. The histological subtypes of thymoma were 1, 2, 1, 1 and 1 cases with type A, AB, B 1, B 2 and B 3. All cases underwent midsternal thoracotomy, 4 cases had thymothymectomy and 2 cases had extended thymothymectomy. Five cases have been alive since the operation. Strong immunoreactivity for bcl-2 and p 53 expression of epidermoid non-keratinizing carcinoma and undifferentiated carcinoma were seen. ki-67 labeling index of epidermoid non-keratinizing carcinoma and undifferentiated carcinoma and type B 3 thymoma were higher than those of the other carcinomas and thymomas.

[Extralobar pulmonary sequestration with aberrant lobulation of the lower lobe; report of a case].

An adult case of extralobar pulmonary sequestration with aberrant lobulation of the right lower lobe is reported. A 32-year-old woman admitted to our hospital with a right intrathoracic tumor in the chest computed tomography (CT). Chest CT showed a mass lesion on the right diaphragm of a diameter 5 cm and abnormal fissure of the right lower lobe. Under the diagnosis of pulmonary sequestration without clearly thick vessels, video-assisted thoracoscopic surgery was performed. The mass existed between the right diaphragm and posterior lower lobe with a thin stalk, and the lower lobe had aberrant lobulation. The resected mass was histopathologically diagnosed as extralobar pulmonary sequestration.

[Ventricular pseudo-false aneurysm after myocardial infarction; report of a case].

A 72-year-old man was admitted to our hospital with chest discomfort and syncope. The echocardiography showed the left ventricular aneurysm. The coronary arteriography revealed a complete occlusion at distal portion of the right coronary artery and anterior aneurysm of the left ventricle was demonstrated. We diagnosed that it was false aneurysm because of communicating with the left ventricle through a small orifice. Surgical repair was carried out after resection of the aneurysm of the left ventricle. The postoperative course was uneventful and discharged on the 33rd day after surgery. Pseudo-false ventricular aneurysm of the left ventricle was diagnosed by histological examination.

Torsion of a benign cyst arising from the tunica vaginalis testis.

We describe a rare case of torsion of a benign cyst originating from the parietal layer of tunica vaginalis. This case presented with acute scrotum. Surgical exploration revealed a cyst arising from the parietal layer of tunica vaginalis of which the pedicle was twisted. When a cystic mass is detected in the scrotum of boys with acute scrotum, torsion of a cyst in the cavum tunica vaginalis testis should be considered.

[Clinical laboratory data and reference intervals standardized in Fukuoka].

In Fukuoka whose population is approximately five million inhabitants, surveys on the accuracy of laboratory data have been performed by the Fukuoka Prefecture Medical Association for the last 30 years. We have been attempting to evaluate the data for routine use since 1988, and it has become possible to share laboratory data between all institutions in Fukuoka prefectures. As a result, reference intervals for 23 clinical chemistry analytes were established in 1995, to which were added in 1996 five serum protein constituents that have been utilized for clinical examinations. Methods for documentations and monitorings the data obtained in the prefecture were also established, standardization of the above analytes extended to 97% of the institutions in the prefecture. Results for 14 of the 23 clinical chemistry analytes have become highly reliable and clinically useful as differences between institutions in terms of results have narrowed. Standardization of other analytes is now in progress.

Standardization of laboratory data and establishment of reference intervals in the Fukuoka Prefecture: a Japanese perspective.

Standardization of 22 clinical chemistry analytes and five serum protein constituents has been performed in the Fukuoka Prefecture, which has a population of approximately five million. The standardization project was established to determine reference intervals for these analytes by educating physicians, medical technologists and staff of medical institutions, and by daily or monthly monitoring the use of common control samples through e-mail. Standardization extended to 97% of the institutions in the prefecture. Results for 14 of the 22 clinical chemistry analytes have become highly reliable and differences between institutions decreased. Standardization of other analytes is now in progress. Regional collaboration based on international guidelines led to a significant improvement in interlaboratory comparability. Areas where further improvements are needed have been identified.

Hepatocarcinogenesis inhibition by caffeine in ACI rats treated with 2-acetylaminofluorene.

The inhibitory effects of caffeine have been demonstrated on the development of various organs in animals. The purpose of the present study was to examine the inhibitory effect of caffeine on hepatocarcinogenesis and to determine the responsive dose of caffeine on hepatocarcinogenesis in young male ACI rats. Animals given a diet containing 2-acetylaminofluorene (2-AAF) for 12 weeks and then a basal diet and tap water containing caffeine for 18 weeks showed statistically significant decreases in the incidence, multiplicity (the number of hepatic tumors per rat) and histological grade compared with rats fed a diet containing carcinogen for 12 weeks followed by tap water alone. Dose-dependent inhibition of hepatocarcinogenesis by caffeine was also seen. The inhibitory effect of caffeine on hepatocarcinogenesis in rats was found when caffeine was administered during the initiation phase.

Correlation of immunohistochemical p53 labeling index with inhibition rate in chemosensitivity test in gastric and colon cancer.

To determine whether the expression of p53, p21, bcl-2 or Ki-67 in cancer cells is predictive of chemosensitivity, immunohistochemical examination of these factors and chemosensitivity assays were performed on colon and gastric cancer specimens. Chemosensitivity tests were performed using CDDP, 5-FU, MMC, or ADR and inhibition rate (IR) was calculated by MTT assay. Before exposure to anticancer drugs, the samples were investigated immunohistochemically for expression of the above factors and after anticancer drug exposure by TUNNEL staining, for the presence of apoptotic cells. With 5-FU and MMC, the apoptotic index was well correlated with IR, so their effects were related to apoptosis. Moreover, with these two agents, the p53 labeling index (LI) was inversely correlated with IR and p21-LI showed a good correlation with IR. We therefore concluded that immunohistochemical studies for p53 and p21 were useful for predicting the chemosensitivities of colon and gastric cancer to MMC and 5-FU.

Near-field fluorescence imaging of single molecules with a resolution in the range of 10 nm.

We demonstrate fluorescence imaging of single molecules, by near-field scanning optical microscopy (NSOM), using the illumination-collection mode of operation, with an aperture probe. Fluorescence images of single dye molecules were obtained with a spatial resolution of 15 nm, which is smaller than the diameter of the aperture (20 nm) of the probe employed. Such super-resolution may be attributable to non-radiative energy transfer from the molecules to the coated metal of the probe since the resolution obtained in the case of conventional NSOM is limited to 30-50 nm due to penetration of light into the metal.

Identification of six novel MYH9 mutations and genotype-phenotype relationships in autosomal dominant macrothrombocytopenia with leukocyte inclusions.

The autosomal dominant macrothrombocytopenia with leukocyte inclusions, May-Hegglin anomaly (MHA), Sebastian syndrome (SBS), and Fechtner syndrome (FTNS), are rare platelet disorders characterized by a triad of giant platelets, thrombocytopenia, and characteristic Döhle body-like leukocyte inclusions. The locus for these disorders was previously mapped on chromosome 22q12.3-q13.2 and the disease gene was recently identified as MYH9, the gene encoding the nonmuscle myosin heavy chain-A. To elucidate the spectrum of MYH9 mutations responsible for the disorders and to investigate genotypephenotype correlation, we examined MYH9 mutations in an additional 11 families and 3 sporadic patients with the disorders from Japan. Korea, and China. All 14 patients had heterozygous MYH9 mutations, including three known mutations and six novel mutations (three missense and three deletion mutations). Two cases had Alport manifestations including deafness, nephritis, and cataracts and had R1165C and E1841K mutations, respectively. However, taken together with three previous reports, including ours, the data do not show clear phenotype-genotype relationships. Thus, MHA, SBS, and FTNS appear to represent a class of allelic disorders with variable phenotypic diversity.

[A case of thymoma with pure red cell aplasia].

A 71-year-old man was admitted to the hospital because of general fatigue. There were few reticulocytes in the peripheral blood and no erythroblasts in the bone marrow. Chest CT revealed an anterior mediastinal tumor. Under a diagnosis of thymoma with PRCA, extended thymothymectomy was performed. Histological diagnosis was mixed type thymoma with no invasive growth beyond the capsule. Administration of predonisolone following surgery was not effective for PRCA. Otherwise, peripheral blood counts were significantly improved following occasional onset of acute bronchitis.

A case report of FSH-producing nasal ectopic pituitary adenoma extending to the frontal cranial fossa.

We report the first case of an ectopic pituitary adenoma in the nasal cavity that produced follicle-stimulating hormone (FSH). A 60-year-old man complaining of left nasal bleeding had a polypoid tumor in the left nasal cavity. Findings of computed tomographic scanning and magnetic resonance imaging showed that the tumor originated from the olfactory cleft, occupied the nasal cavity, and extended to the frontal cranial fossa. Results of histologic examination suggested ectopic pituitary adenoma. Magnetic resonance imaging results showed the pituitary gland to be normal. Electron microscopy findings demonstrated a large number of secretory granules in the tumor cells that were positive for FSH on immunohistochemical analyses. Serum gonadotropin levels were normal, and no clinical signs of hypersecretory syndrome were noted. The above findings led us to establish the diagnosis of FSH-producing ectopic pituitary adenoma. The patient underwent craniofacial resection of the tumor followed by an uneventful recovery. The pathologic findings and clinical course of the case were comparable to those of FSH-producing adenomas arising from the pituitary gland.

Correlation of loss of CD4 T cells with plasma levels of both soluble form Fas (CD95) Fas ligand (FasL) in HIV-infected infants.

Fas and Fas ligand (FasL), members of the TNFR and TNF families of molecules involved in apoptosis, respectively, are expressed in membrane-associated as well as soluble forms. Soluble Fas (sFas) and sFasL were evaluated in sequential samples from 16 HIV-infected and 11 HIV-exposed uninfected infants at ages 0-13 months. Regardless of the state of infection, age-dependent decreases in peripheral CD4 T cell counts and increases in sFas and sFasL were noted. However, decreases of the percentage CD4 T cells were more prominent in HIV-infected infants, and this was correlated significantly with increased plasma levels of sFas and sFasL (P = 0.002 and 0.004, respectively). Moreover, the levels of sFas in HIV-infected infants were found to be directly correlated with plasma HIV RNA (P = 0.03) and were significantly increased as early as age <1 month and prior to the onset of CD4 T cell decline. In uninfected infants, there was no such correlation between CD4 counts and the levels of sFas/sFasL. Plasma levels of sFas and sFasL may thus be important indicators of disease progression in perinatal HIV infection.