O-183 Frequent spontaneous abortion in pregnancies followed by ICSI using frozen sperm from patients with testicular germ cell tumor (TGCT)

Study question

Despite the high rate of sperm chromosome abnormalities in testicular germ cell tumor (TGCT), why is newborn aneuploidy rate in pregnancies with TGCT patient normal?

Summary answer

Miscarriage rate is higher in the pregnancy of TGCT patients than of non-TGCT cancer patients, although the pregnancy rate in ICSI was not significantly different.

What is known already

Previous reports showed higher sperm aneuploidy in TGCT patients than control males. The sperm aneuploidy rate is high before treatment, and after radical treatments peaked at 6 months after treatment and remained high until 24 months after treatment. However, in the Swedish government base study, the rate of newborn malformations including aneuploidy in all pregnancy with TGCT patients was higher than without TGCT, but not statistically significant. In only natural pregnancies, the rate was not significantly different between the two groups. The cause for discrepancy within sperm aneuploidy and newborn aneuploidy was not well clarified.

Study design, size, duration

To clarify the mechanism for the purifying selection of aneuploid sperm in conception, we examined ICSI cases with TGCT patients that did not include natural sperm competition and compared to controls with non-TGCT cancer patient, who have normal rate of aneuploid sperm. By investigating ICSI outcomes, we aimed to determine which stage of embryonic development are affected by the sperm of TGCT patients.

Participants/materials, setting, methods

Under ethical review of Yokohama city university, the 10 TGCT patients (123 oocytes) and 16 non-TGCT cancer patients (251 oocytes) who underwent ICSI with their frozen sperm from 2012 to 2021 were enrolled. Fertilization, embryo viability and embryo transfer outcomes (pregnancy and miscarriage rate) were examined between two groups underwent ICSI with cryopreserved sperm for fertility preservation. Clinical information was retrospectively collected from medical records.

Main results and the role of chance

The patients' age of sperm cryopreservation was 21-56 years old. 10 cases of TGCT were diagnosed as seminoma (3), non seminoma (6), and unknown (2). 15 cases of non-TGCT were diagnosed as malignant blood diseases (9), prostate cancer (2), bladder cancer (1), and others (3). In both groups, all patients were treated by ICSI with cryopreserved sperm obtained prior to chemotherapy. The mean age of female partners in TGCT was 33.2±3.5 years and not different with 35.8±3.4 years in non-TGCT meaning no different age factor. The fertilization rate, viable embryo rate, pregnancy rate and chemical abortion rate of TGCT vs non-TGCT group were 76.4% vs 67.7%, 64.3% vs 61.7%, 37.1% vs 21.7%, 7.1% vs 23.1%, respectively. Those developmental evaluations were not significantly different between two groups. However, spontaneous abortion rate was significantly higher 46.2% in TGCT group than 10% in non-TGCT group (p < 0.05). Further, in our follow-up, no congenital malformations in the babies born in either group (5 babies in TGCT vs 7 babies in non-TGCT group). The outcome of ICSI using sperm in TGCT patients show normal pregnancy rate but include higher spontaneous abortions rate, suggesting aneuploid embryo were negatively purifying selected under post-implantation stage.

Limitations, reasons for caution

Because ICSI with fertility-preserving frozen sperm in TGCT patient is rare even in reproduction center in general university hospital, single center analysis is still small and limited. More case reports and studies for TGCT fertility preservation are needed for more accurate evaluation.

Wider implications of the findings

In TGCT patients, chromosome aberrations and DNA fragmentation of sperm may not be apparent in natural pregnancies with normal sperm competition, but may become apparent as spontaneous abortions when ICSI were performed, suggesting PGT-A can predict and avoid the hidden risk of repeated pregnancy loss in ICSI to TGCT patients.

Trial registration number

not applicable

P–572 Purifying selection for aneuploidy cells in mosaicism embryo at post-implantation stage

Study question

Why low ratio mosaicism embryos develop to normal karyotype babies?

Summary answer

Our in vitro implantation assay clarified purifying selection for aneuploid cells in post implantation embryos.

What is known already

There are some reports about healthy live birth after transfer of mosaic embryos, which was reported for the first time from Italy in 2015. It is also reported that the abnormal cell is screened with the mouse in the embryo development, and only a normal cell contributes to the development. But it has not been examined in human.

Study design, size, duration

To clarify the change of aneuploid cells and mitochondrial activity in human embryo, we biopsied several parts from one blastocyst and examined karyotype. After in vitro implantation assay for biopsied embryos, we compared the karyotype of biopsy sample with that of cultured cell mass.

Participants/materials, setting, methods

Under the ethical review of Yokohama City University and informed consent with patients, we collected human surplus blastocysts those are donated after successful clinical treatment or discarded because of poor development grade. We biopsied multiple parts from one blastocyst and cultured the biopsied embryos, and extracted whole DNA from the biopsy samples and cultured embryos. Karyotyping by next generation sequencing were performed.

Main results and the role of chance

We analyzed 34 samples from 11 embryos, including 25 biopsy sample from 11 embryos and 9 cell mass from 7 cultured embryos. In the karyotype tracking results, even though biopsy sample analysis before the culture were uniformed aneuploid or chromosome mosaic, the developing embryo cell mass had normal karyotype. In one embryo as an example, among the three biopsied extra trophectoderm samples from that, two of them were mosaic, and one of them had uniformed chromosome 21 trisomy and chromosome 16 mosaic monosomy. But the embryo formed multiple cell mass in implantation assay. We examined karyotype of three cell mass, and the result from all were normal karyotype. We suggested that the chromosome aberration cells were screened in the human embryo development, and when the function was not carried out the embryo stopped the development.

Limitations, reasons for caution

Because of small number of samples available, we need more samples for a more accurate evaluation. Furthermore, we cannot evaluate the absolute mechanism that cells with chromosome aberration decreases.

Wider implications of the findings: Conventional PGT-A techniques are based on uniformed embryos developing hypothesized past time. As showed in some clinical reports, PGT-A can reduce of spontaneous abortion and chance of embryo transfer. Thinking about aneuploid cell purifying system in embryo development, effectiveness of PGT-A should be more questionable for infertility treatment.

Trial registration number

A200326004

Changes in platelet Bax levels contribute to impaired platelet response to thrombin after cardiopulmonary bypass: prospective observational clinical and laboratory investigations

Background

Anucleate platelets can undergo apoptosis in response to various stimuli, as do nucleated cells. Cardiopulmonary bypass (CPB) causes platelet dysfunction and can also activate platelet apoptotic pathways. We therefore evaluated time-dependent changes in blood platelet Bax (a pro-apoptotic molecule) levels and platelet dysfunction after cardiac surgery.

Methods

We assessed blood samples obtained from subjects having on-pump or off-pump coronary artery bypass graft surgery ( n =20 each). We also evaluated the in vitro effects of platelet Bax increase in eight healthy volunteers.

Results

Thrombin-induced platelet calcium mobilisation and platelet-surface glycoprotein Ib (GPIb) expression were lowest at weaning from CPB and did not recover on postoperative day one. On-pump surgery increased platelet expression of Bax, especially the oligomerised form, along with translocation of Bax from the cytosol to mitochondria and platelet-surface tumour necrosis factor-alpha (TNF-α)-converting enzyme (TACE) expression. In contrast, mitochondrial cytochrome c expression was reduced. While similar in direction, the magnitude of the observed changes was smaller in patients having off-pump surgery. In vitro , a cell-permeable Bax peptide increased platelet Bax expression to the same extent seen during bypass and produced similar platelet changes. These apoptotic-like changes were largely reversed by Bcl-xL pre-administration, and were completely reversed by combined application of inhibitors that stabilise outer mitochondrial membrane permeability and TACE.

Conclusions

CPB increases platelet Bax expression, which contributes to reduced platelet-surface GPIb expression and thrombin-induced platelet calcium changes. These changes in platelet apoptotic signalling might contribute to platelet dysfunction after CPB.

Clinical trial registration

UMIN Clinical Trials Registry (number UMIN000006033).

Search for Boosted Dark Matter Interacting with Electrons in Super-Kamiokande

A search for boosted dark matter using 161.9 kt yr of Super-Kamiokande IV data is presented. We search for an excess of elastically scattered electrons above the atmospheric neutrino background, with a visible energy between 100 MeV and 1 TeV, pointing back to the Galactic center or the Sun. No such excess is observed. Limits on boosted dark matter event rates in multiple angular cones around the Galactic center and Sun are calculated. Limits are also calculated for a baseline model of boosted dark matter produced from cold dark matter annihilation or decay. This is the first experimental search for boosted dark matter from the Galactic center or the Sun interacting in a terrestrial detector.

Digitised evaluation of speech intelligibility using vowels in maxillectomy patients

Among the functional disabilities that patients face following maxillectomy, speech impairment is a major factor influencing quality of life. Proper rehabilitation of speech, which may include prosthodontic and surgical treatments and speech therapy, requires accurate evaluation of speech intelligibility (SI). A simple, less time-consuming yet accurate evaluation is desirable both for maxillectomy patients and the various clinicians providing maxillofacial treatment. This study sought to determine the utility of digital acoustic analysis of vowels for the prediction of SI in maxillectomy patients, based on a comprehensive understanding of speech production in the vocal tract of maxillectomy patients and its perception. Speech samples were collected from 33 male maxillectomy patients (mean age 57.4 years) in two conditions, without and with a maxillofacial prosthesis, and formant data for the vowels /a/,/e/,/i/,/o/, and /u/ were calculated based on linear predictive coding. The frequency range of formant 2 (F2) was determined by differences between the minimum and maximum frequency. An SI test was also conducted to reveal the relationship between SI score and F2 range. Statistical analyses were applied. F2 range and SI score were significantly different between the two conditions without and with a prosthesis (both P < .0001). F2 range was significantly correlated with SI score in both the conditions (Spearman's r = .843, P < .0001; r = .832, P < .0001, respectively). These findings indicate that calculating the F2 range from 5 vowels has clinical utility for the prediction of SI after maxillectomy.

Extensive use of vasodilator agents and functional echocardiography to monitor extremely-low-birth-weight infants in Japan

National surveys were conducted in Japan to assess the current practices for circulatory management of extremely-low-birth-weight infants (ELBWIs) in acute phases. Approximately 80 and 100 institutions were surveyed in 2006 and 2011, respectively. Echocardiography was identified as an important diagnostic tool at 95% of the surveyed institutions. Furthermore, 74% of the institutions survey in 2011 used vasodilator agents. In 2011, the mean velocity of circumferential fiber shortening (mVcfc) and left ventricular end-systolic wall stress (ESWS) were used by 60% of the surveyed institutions to evaluate the relationship between afterload of the left ventricle and left ventricular contractility. Overall, the data collected from these national surveys clarified the current practices for circulatory management of ELBWIs in Japan, particularly the use of echocardiography and cardiovascular agents, including catecholamines and vasodilators.

High expression of CD109 antigen regulates the phenotype of cancer stem-like cells/cancer-initiating cells in the novel epithelioid sarcoma cell line ESX and is related to poor prognosis of soft tissue sarcoma

Epithelioid sarcoma (ES) is a relatively rare, highly malignant soft tissue sarcoma. The mainstay of treatment is resection or amputation. Currently other therapeutic options available for this disease are limited. Therefore, a novel therapeutic option needs to be developed. In the present study, we established a new human ES cell line (ESX) and analyzed the characteristics of its cancer stem-like cells/cancer-initiating cells (CSCs/CICs) based on ALDH1 activity. We demonstrated that a subpopulation of ESX cells with high ALDH1 activity (ALDH(high) cells) correlated with enhanced clonogenic ability, sphere-formation ability, and invasiveness in vitro and showed higher tumorigenicity in vivo. Next, using gene expression profiling, we identified CD109, a GPI-anchored protein upregulated in the ALDH(high) cells. CD109 mRNA was highly expressed in various sarcoma cell lines, but weakly expressed in normal adult tissues. CD109-positive cells in ESX predominantly formed spheres in culture, whereas siCD109 reduced ALDH1 expression and inhibited the cell proliferation in vitro. Subsequently, we evaluated the expression of CD109 protein in 80 clinical specimens of soft tissue sarcoma. We found a strong correlation between CD109 protein expression and the prognosis (P = 0.009). In conclusion, CD109 might be a CSC/CIC marker in epithelioid sarcoma. Moreover, CD109 is a promising prognostic biomarker and a molecular target of cancer therapy for sarcomas including ES.

The gating mechanism of the bacterial mechanosensitive channel MscL revealed by molecular dynamics simulations: from tension sensing to channel opening

One of the ultimate goals of the study on mechanosensitive (MS) channels is to understand the biophysical mechanisms of how the MS channel protein senses forces and how the sensed force induces channel gating. The bacterial MS channel MscL is an ideal subject to reach this goal owing to its resolved 3D protein structure in the closed state on the atomic scale and large amounts of electrophysiological data on its gating kinetics. However, the structural basis of the dynamic process from the closed to open states in MscL is not fully understood. In this study, we performed molecular dynamics (MD) simulations on the initial process of MscL opening in response to a tension increase in the lipid bilayer. To identify the tension-sensing site(s) in the channel protein, we calculated interaction energy between membrane lipids and candidate amino acids (AAs) facing the lipids. We found that Phe78 has a conspicuous interaction with the lipids, suggesting that Phe78 is the primary tension sensor of MscL. Increased membrane tension by membrane stretch dragged radially the inner (TM1) and outer (TM2) helices of MscL at Phe78, and the force was transmitted to the pentagon-shaped gate that is formed by the crossing of the neighboring TM1 helices in the inner leaflet of the bilayer. The radial dragging force induced radial sliding of the crossing portions, leading to a gate expansion. Calculated energy for this expansion is comparable to an experimentally estimated energy difference between the closed and the first subconductance state, suggesting that our model simulates the initial step toward the full opening of MscL. The model also successfully mimicked the behaviors of a gain of function mutant (G22N) and a loss of function mutant (F78N), strongly supporting that our MD model did simulate some essential biophysical aspects of the mechano-gating in MscL.

SYT-SSX breakpoint peptide vaccines in patients with synovial sarcoma: a study from the Japanese Musculoskeletal Oncology Group

In the present study, we evaluated the safety and effectiveness of SYT-SSX-derived peptide vaccines in patients with advanced synovial sarcoma. A 9-mer peptide spanning the SYT-SSX fusion region (B peptide) and its HLA-A*2402 anchor substitute (K9I) were synthesized. In Protocols A1 and A2, vaccines with peptide alone were administered subcutaneously six times at 14-day intervals. The B peptide was used in Protocol A1, whereas the K9I peptide was used in Protocol A2. In Protocols B1 and B2, the peptide was mixed with incomplete Freund's adjuvant and then administered subcutaneously six times at 14-day intervals. In addition, interferon-α was injected subcutaneously on the same day and again 3 days after the vaccination. The B peptide and K9I peptide were used in Protocols B1 and B2, respectively. In total, 21 patients (12 men, nine women; mean age 43.6 years) were enrolled in the present study. Each patient had multiple metastatic lesions of the lung. Thirteen patients completed the six-injection vaccination schedule. One patient developed intracerebral hemorrhage after the second vaccination. Delayed-type hypersensitivity skin tests were negative in all patients. Nine patients showed a greater than twofold increase in the frequency of CTLs in tetramer analysis. Recognized disease progression occurred in all but one of the nine patients in Protocols A1 and A2. In contrast, half the 12 patients had stable disease during the vaccination period in Protocols B1 and B2. Of note, one patient showed transient shrinkage of a metastatic lesion. The response of the patients to the B protocols is encouraging and warrants further investigation.

SOX2 is overexpressed in stem-like cells of human lung adenocarcinoma and augments the tumorigenicity

Recently, the SOX2 gene has been reported to be amplified in human lung squamous cell carcinomas. However, its roles in human lung adenocarcinomas are still elusive. In this study, we analyzed the functions of SOX2 in cancer stem-like cells (CSCs)/cancer-initiating cells (CICs) derived from human lung adenocarcinoma. Human lung CSCs/CICs were isolated as higher tumorigenic side population (SP) cells using Hoechst 33342 dye from several lung cancer cell lines. Four of nine lung cancer cell lines were positive for SP cells (LHK2, 1-87, A549, Lc817). The ratios of SP cells ranged from 0.4% for Lc817 to 2.8% for LHK2. To analyze the molecular aspects of SP cells, we performed microarray screening and RT-PCR analysis, and isolated SOX2 as one of a SP cell-specific gene. SOX2 was expressed predominantly in LHK2 and 1-87 SP cells, and was also expressed in several other cancer cell lines. The expression of SOX2 protein in primary human lung cancer tissues were also confirmed by immunohistochemical staining, and SOX2 was detected in more than 80% of primary lung cancer tissues. To address SOX2 molecular functions, we established a SOX2-overexpressed LHK2 and A549 cell line (LHK2-SOX2 and A549-SOX2). LHK2-SOX2 cells showed higher rates of SP cells and higher expression of POU5F1 compared with control cells. LHK2-SOX2 and A549-SOX2 cells showed relatively higher tumorigenicity than control cells. On the other hand, SOX2 mRNA knockdown of LHK2 SP cells by gene-specific siRNA completely abrogated tumorigenicity in vivo. These observations indicate that SOX2 has a role in maintenance of stemness and tumorigenicity of human lung adenocarcinoma CSCs/CICs and is a potential target for treatment.

Constant expression of mouse calpastatin isoforms during differentiation in myoblast cell line, C2C12

C2C12 is a myoblast cell line which is used to studydifferentiation into multinucleated cells in vitro. Addition of calpain inhibitors, calpeptin orE-64d, to the culture medium prevented the myoblasticfusion of C2C12 cells. Immunoblot studies usingaffinity-purified antibody, revealed that the expressedlevels of mouse calpastatin remained unaltered duringC2C12 cell fusion. The detected calpastatin migratedas a protein of 130 kDa on SDS-polyacrylamide gelelectrophoresis. The estimated molecular mass wassomewhat greater than that in mouse liver anderythrocytes, and much greater than that reported inrat myoblasts. The 130 kDa isoform may contain anadditional N-terminal region designated XL domainfound in bovine calpastatin.

Autologous CTL response against cancer stem-like cells/cancer-initiating cells of bone malignant fibrous histiocytoma

Malignant fibrous histiocytoma (MFH) of the bone is an aggressive tumor with high rates of local recurrence and metastasis. The development of novel therapeutic approaches is critical to improve the prognosis of patients with MFH. We reported previously that the side population (SP) cells of the MFH2003 bone MFH cell line have the characteristics of cancer stem-like cells (CSC)/cancer-initiating cells. In the present study, to establish immunotherapy targeting CSC, we analyzed cell surface immune molecules on SP cells of the MHF2003 cell line, as well as autologous CTL responses against these SP cells in the tumor microenvironment and peripheral circulating lymphocytes, using autologous tumor-infiltrating lymphocytes and autologous CTL clones derived from peripheral blood, respectively. We found that the SP cells expressed human leukocyte antigen (HLA) Class I molecules on the cell surface. The autologous tumor-infiltrating lymphocyte line TIL2003 recognized both the SP and main population cells of the MFH2003 cell line. Next, we induced the CTL clone Tc4C-6 by mixed lymphocyte tumor cell culture using autologous peripheral blood mononuclear cells and freshly isolated SP cells, followed by a limiting dilution procedure. The Tc4C-6 clone showed specific cytotoxicity against the SP cells. Moreover, the cytotoxicity against SP cells was blocked by the anti-HLA Class I antibody W6/32. In conclusion, the findings of the present study support the idea that CSC of bone MFH are recognized by autologous CTL in the tumor microenvironment and peripheral circulating lymphocytes. Thus, CTL-based immunotherapy could target CSC of bone sarcoma to help prevent tumor recurrence.

Cytotoxic T-lymphocyte antigen 4 haplotype correlates with relapse and survival after allogeneic hematopoietic SCT

CTLA-4 is a negative regulator of activated T cells and the association of CTLA-4 polymorphisms with autoimmune diseases and transplant outcome has been reported. We evaluated the effect of donor CTLA-4 polymorphisms on outcome after allogeneic hematopoietic SCT (HSCT). We analyzed 147 Japanese HLA-matched sibling recipients and their donors who had undergone allogeneic HSCT. Genotyping of three single-nucleotide polymorphisms in CTLA-4 (-318, +49, CT60) was performed using TaqMan-PCR. According to the international HapMap database, only these three CTLA-4 haplotypes, classified as C-G-G, C-A-A and T-A-G, are present in the Japanese population. In this study, percentage expression of the C-G-G, C-A-A and T-A-G haplotypes was 59.5, 30.6 and 9.9%, respectively. Recipients of the C-A-A haplotype donor showed a significantly lower risk of relapse (HR: 0.54, 95% CI: 0.30-0.97, P=0.040) and a trend toward higher OS (HR: 0.61, 95% CI: 0.36-1.0, P=0.054) than did recipients of a donor without the C-A-A haplotype. The presence or absence of the C-A-A haplotype did not affect GVHD or non-relapse mortality. As the presence of the C-A-A haplotype reduced relapse risk and improved survival after allogeneic HSCT, this CTLA-4 haplotype may provide useful information for donor selection.

Maturational changes in the feeding behaviour of infants - a comparison between breast-feeding and bottle-feeding

AIM

To obtain a better understanding of the changes in feeding behaviour from 1 to 6 months of age. By comparing breast- and bottle-feeding, we intended to clarify the difference in longitudinal sucking performance.

METHODS

Sucking variables were consecutively measured for 16 breast-fed and eight bottle-fed infants at 1, 3 and 6 months of age.

RESULTS

For breast-feeding, number of sucks per burst (17.8 +/- 8.8, 23.8 +/- 8.3 and 32.4 +/- 15.3 times), sucking burst duration (11.2 +/- 6.1, 14.7 +/- 8.0 and 17.9 +/- 8.8 sec) and number of sucking bursts per feed (33.9 +/- 13.9, 28.0 +/- 18.2 and 18.6 +/- 12.8 times) at 1, 3 and 6 months of age respectively showed significant differences between 1 and 6 months of age (p < 0.05). The sucking pressure and total number of sucks per feed did not differ among different ages. Bottle-feeding resulted in longer sucking bursts and more sucks per burst compared with breast-feeding in each month (p < 0.05).

CONCLUSION

The increase in the amount of ingested milk with maturation resulted from an increase in bolus volume per minute as well as the higher number of sucks continuously for both breast- and bottle-fed infants.

Side population cells have the characteristics of cancer stem-like cells/cancer-initiating cells in bone sarcomas

Background:

Several human cancers have been found to contain cancer stem-like cells (CSCs) having cancer-initiating ability. However, only a few reports have shown the existence of CSCs in bone and soft tissue sarcomas. In this study, we identified and characterised side population (SP) cells that showed drug-resistant features in human bone sarcoma cell lines.

Methods:

In seven osteosarcoma cell lines (OS2000, KIKU, NY, Huo9, HOS, U2OS and Saos2) and in one bone malignant fibrous histiocytoma (MFH) cell line (MFH2003), the frequency of SP cells was analysed. Tumourigenicity of SP cells was assessed in vitro and in vivo. Gene profiles of SP cells and other populations (main population; MP) of cells were characterised using cDNA microarrays.

Results:

SP cells were found in NY (0.31%) and MFH2003 (5.28%). SP cells of MFH2003 formed spherical colonies and re-populated into SP and MP cells. In an NOD/SCID mice xenograft model, 1 × 10³ sorted SP cell-induced tumourigenesis. cDNA microarray analysis showed that 23 genes were upregulated in SP cells.

Conclusions:

We showed that SP cells existed in bone sarcoma cell lines. SP cells of MFH2003 had cancer-initiating ability in vitro and in vivo. The gene profiles of SP cells could serve as candidate markers for CSCs in bone sarcomas.

Prognostic impact and immunogenicity of a novel osteosarcoma antigen, papillomavirus binding factor, in patients with osteosarcoma

To develop peptide-based immunotherapy for osteosarcoma, we previously identified papillomavirus binding factor (PBF) as a cytotoxic T lymphocytes (CTL)-defined osteosarcoma antigen in the context of human leukocyte antigen (HLA)-B55. In the present study, we analyzed the distribution profile of PBF in 83 biopsy specimens of osteosarcomas and also the prognostic impact of PBF expression in 78 patients with osteosarcoma who had completed the standard treatment protocols. Next, we determined the antigenic peptides from PBF that react with peripheral T lymphocytes of HLA-A24(+) patients with osteosarcoma. Immunohistochemical analysis revealed that 92% of biopsy specimens of osteosarcoma expressed PBF. PBF-positive osteosarcoma conferred significantly poorer prognosis than those with negative expression of PBF (P = 0.025). In accordance with the Bioinformatics and Molecular Analysis Section score, we synthesized 10 peptides from the PBF sequence. Subsequent screening with an HLA class I stabilization assay revealed that peptide PBF A24.2 had the highest affinity to HLA-A24. CD8(+) T cells reacting with a PBF A24.2 peptide were detected in eight of nine HLA-A24-positive patients with osteosarcoma at the frequency from 5 x 10(-7) to 7 x 10(-6) using limiting dilution/mixed lymphocyte peptide culture followed by tetramer-based frequency analysis. PBF A24.2 peptide induced CTL lines from an HLA-A24-positive patient, which specifically killed an osteosarcoma cell line that expresses both PBF and HLA-A24. These findings suggested prognostic significance and immunodominancy of PBF in patients with osteosarcoma. PBF is the candidate target for immunotherapy in patients with osteosarcoma.

Clonal T-cell response against autologous pleomorphic malignant fibrous histiocytoma antigen presented by retrieved HLA-A*0206

Towards the goal of identifying tumor-rejection antigens on eradicated tumors in bone and soft tissue sarcomas, we evaluated the immune response against antigens presented by lost HLA class I molecules. Tumor specimens and peripheral blood samples were obtained from a 70-year-old woman with pleomorphic malignant fibrous histiocytoma. Over 1-year culture, a tumor cell line (MFH2004) was established. A B-cell line infected with Epstein-Barr virus (B2004-EBV) was developed from the blood samples. HLA genotypes of B2004-EBVcells were A*0206/2402, B*4006/4601, and C*0102/0801, whereas MFH2004 cells were defective for A*0206, B*4006, and C*0102. Loss of HLA-A2 expression was also proved immunohistochemically in the primary tumor tissues. Lost HLA-A2 in MFH2004 cells was retrieved by transfection of HLA-A*0206 cDNA to develop MFH2004-A2. Attempts to induce CTLs by mixed culture with autologous T cells and MFH2004 cells resulted in failure. In contrast, those with MFH2004-A2 induced CTL clones CTL2004-c6 and CTL2004-c17. These CTL clones specifically killed MFH2004-A2 but not MFH2004 or B2004-EBV in an HLA-A2-restricted manner. These findings suggest that CTL2004-c6 and CTL2004-c17 recognize autologous tumor-rejection antigens presented by HLA-A*0206, which may have been expressed by tumor cells that had been eradicated by the host's immunosurveillance system.

Insulin resistance and impaired myocardial fatty acid metabolism in dialysis patients with normal coronary arteries

We investigated whether insulin resistance is associated with impaired cardiac fatty acid metabolism in maintenance hemodialysis patients without coronary artery disease. We studied 55 nondiabetic (63+/-11 years old) and 51 diabetic (61+/-10 years old) hemodialysis patients with normal coronary arteries, using single-photon emission computed tomography (SPECT) with an iodinated fatty acid analogue, iodine-123-beta-methyl iodophenyl-pentadecanoic acid ((123)I-BMIPP), to evaluate cardiac fatty acid metabolism. SPECT imaging was graded regionally from 0 (normal) to 4 (absence of tracer) to calculate a summed score for 17 left ventricular segments. Insulin resistance was determined using the homeostasis model assessment index of insulin resistance (HOMA-IR). HOMA-IR correlated with summed BMIPP score in nondiabetic and diabetic patients. Stepwise multiple regression analysis showed that HOMA-IR was independently associated with BMIPP summed score in nondiabetic (beta=0.774, t=9.218, P=0.0001) and diabetic patients (beta=0.792, t=9.079, P=0.0001). Left ventricular ejection fraction was lower in nondiabetic subjects with BMIPP summed score of at least 6 plus HOMA-IR of at least 4 than in others with lower values for both assessments (53.1+/-13.8%, n=20 vs 67.7+/-9.1%, n=23, P=0.0002); this was also true in diabetic subjects (50.9+/-15.2%, n=24 vs 71.0+/-13.6%, n=11, P=0.0007). Association between insulin resistance and impaired cardiac fatty acid metabolism may contribute to left ventricular dysfunction in patients with maintenance hemodialysis without coronary diseases.

Influence of diabetes mellitus on diagnostic potential of iodine-123-BMIPP imaging for coronary artery stenosis in hemodialysis patients

BACKGROUND

Single-photon emission computed tomography (SPECT) using a fatty acid analogue, iodine-123-beta-methyl iodophenyl-pentadecanoic acid (123I-BMIPP), as a tracer may be effective for detecting coronary artery disease in end-stage renal disease (ESRD) patients. In this study, we investigated whether the presence of diabetes mellitus may affect the diagnostic potential of BMIPP SPECT for detecting coronary stenosis in ESRD patients.

METHODS

123I-BMIPP SPECT was performed in 98 diabetic hemodialysis patients (male to female ratio 66:32; mean age 63.6+/-9.8 years) and 103 nondiabetic hemodialysis patients (68:35; 64.5+/-10.4 years), followed by coronary angiography within 60 days of the SPECT. SPECT imaging was evaluated and graded on a 5-point scale (0=normal, 4=absence of tracer) and assessed as a BMIPP summed score for 17 left ventricular segments.

RESULTS

Coronary angiography revealed that 72.4% (71/98) of the diabetic patients and 56.3% (58/103) of the non-diabetic patients had significant coronary stenosis more than 50%; incidences of asymptomatic coronary stenosis were 77.5% in diabetic patients and 72.4% in nondiabetic patients. When a BMIPP summed score of 8 or more was defined as abnormal, sensitivity, specificity and accuracy for detecting coronary stenosis by BMIPP SPECT were 97.2, 63.0 and 87.8% in diabetic patients, and 96.6, 73.3 and 86.4% in nondiabetic patients. In receiver operating characteristic analysis, the areas under the curve of BMIPP SPECT to diagnose coronary stenosis were 0.897 in diabetic and 0.906 in nondiabetic patients.

CONCLUSIONS

BMIPP SPECT seems to be able to detect coronary stenosis in diabetic as well as nondiabetic hemodialysis patients.

Echocardiographic assessment of early circulatory status in preterm infants with suspected intrauterine infection

OBJECTIVE

To assess early circulatory status in very low birthweight (VLBW) infants with suspected intrauterine infections.

PATIENTS

Thirteen VLBW infants who were diagnosed with prenatal infections because of raised serum IgM at birth (infectious group), and 39 infants matched for gestational age and birth weight (control group).

METHODS

Echocardiographic assessments were performed consecutively from birth to day 28 in all VLBW infants. Left ventricular output (LVO) and left ventricular stroke volume (LVSV) were measured using Doppler echocardiography. Pulsed Doppler assessment of pulmonary artery pressure (PAP) was performed using the corrected ratio of the pulmonary artery acceleration time to the right ventricular ejection time (AT/RVET(c)). Blood flow in the superior mesenteric artery (SMA) was also evaluated by Doppler ultrasound.

RESULTS

Mean LVO and LVSV were both significantly higher in the infectious group than in the control group at 12 hours (LVO; 188 v 154 ml/kg/min) and 72 hours (LVO; 216 v 173 ml/kg/min) of life. Pulsed Doppler assessment of PAP showed that mean AT/RVET(c) values were significantly lower in the infectious group than in the control group at 48 hours, 96 hours, day 14, and day 28. In the analysis of SMA flow velocities, both peak systolic velocities and time averaged velocities had decreased significantly in the infectious group compared with the control group at 24 hours, 36 hours, 96 hours, and day 28.

CONCLUSIONS

VLBW infants with suspected prenatal infection showed a unique circulation status, namely high cardiac output, latency of high PAP, and low organ flow.

Early hypocarbia of preterm infants: its relationship to periventricular leukomalacia and cerebral palsy, and its perinatal risk factors

AIM

To clarify clinical interactions between early hypocarbia, periventricular leukomalacia (PVL) and cerebral palsy of preterm infants.

METHODS

Serial measurements of PaCO2 using arterial blood samples at 3, 6, 12, 24 and 48 h of life were performed for 115 very-low-birthweight infants admitted between 1995 and 1999. Severe early hypocarbia, defined when at least two of five PaCO2 values showed 3.3 kPa or less, was observed in eight infants (hypocarbia group). Preterm PVL was diagnosed by serial ultrasonographic examinations and cranial magnetic resonance imaging, and subsequently classified into early-onset PVL diagnosed within 14 d, or late-onset PVL after 14 d. Perinatal risk factors for early hypocarbia were investigated from the mothers' records and interviews with obstetricians.

RESULTS

The average birthweight in the hypocarbia group was significantly smaller than that in the control group (p < 0.01). The occurrence of PVL in the hypocarbia group was not different from that in the control group. Early hypocarbia was significantly related to late-onset PVL (p < 0.001), but not related to early-onset PVL. The incidence of cerebral palsy in the hypocarbia group was significantly higher than that in the control group (p < 0.001). Multivariate analysis showed that both low birthweight and number of maternal previous abortions were predictive for early hypocarbia.

CONCLUSION

Early hypocarbia of preterm infants in our hospital was significantly associated with both cerebral palsy and late-onset PVL, but not with early-onset PVL. The background of the three clinical events, early hypocarbia, PVL, and cerebral palsy, may not be identical in human newborns.

Serial pulsed Doppler assessment of early left ventricular output in critically ill very low-birth-weight infants

Serial, detailed assessments of left ventricular output (LVO) in critically ill very low-birth-weight (VLBW) infants of four different gestational ages were performed in the early neonatal period using pulsed Doppler echocardiography. Initially, the LVO values of all groups at 3 hours of age were relatively high. However, LVO dropped transiently at 12 hours and then increased again after 24 hours reaching a steady level of 160-180 ml/kg/min after 48 hours of age. In all four groups, heart rate also decreased significantly at 12 hours of age but did not increase at 24 hours of age. Both the left ventricular stroke volume and the left ventricular ejection fraction in all groups exhibited similar longitudinal changes to those observed for LVO. The LVO values observed in the lower gestational age group were significantly lower than those observed in the upper gestational group before 24 hours of age. Both patent ductus arteriosus and mechanical ventilation did not significantly influence the changes in LVO of VLBW infants at least before 36 hours of age. Our results suggest that in the early neonatal period, there are drastic changes in LVO of VLBW infants that reflect not only changes in heart rate but also changes in myocardial contractility.

A longitudinal study of disturbances of the hypothalamic-pituitary-adrenal axis in women with progestin-negative functional hypothalamic amenorrhea

OBJECTIVE

To longitudinally evaluate disturbances of the hypothalamic-pituitary-adrenal (HPA) axis in women with secondary progestin-negative hypothalamic amenorrhea.

DESIGN

Retrospective cohort study.

SETTING

Yokohama City University, Yokohama, Japan.

PATIENT(S)

Twenty-four women with progestin-negative hypothalamic amenorrhea.

INTERVENTION(S)

Administration of human corticotropin-releasing hormone (hCRH) and treatment with a combination of estrogen and progesterone.

MAIN OUTCOME MEASURE(S)

Plasma cortisol and ACTH concentrations and period required for recovery from amenorrhea.

RESULT(S)

Plasma ACTH concentrations 30 and 60 minutes after injection of hCRH and the percent maximum increment (%Cmax) of ACTH were significantly lower in the amenorrheic patients compared with the control group patients. The basal cortisol was significantly higher, and the %Cmax of cortisol was significantly lower. In the 16 patients who recovered from amenorrhea, there was a significant positive correlation (Y = 1.93X-10.8, r = 0.629) between the basal cortisol concentrations (X) and the period for recovery (Y). The serum E2 gradually increased before recovery, and this E2 increase was preceded by changes in the plasma cortisol concentration and the %Cmax values of cortisol and ACTH.

CONCLUSION(S)

The CRH test might be useful for evaluating the roles of stress and for estimating the period required for recovery in hypothalamic amenorrhea.

[Surveillance of various enteropathogenic bacteria from diarrheal cases during 1989-1999 in Kobe City]

Incidence of various enteropathogenic bacteria was examined from diarrheal faecal samples that were collected from the patients of Kobe City General Hospital and some station hospitals (23,862), and from overseas travelers (2,855) over a period of decade (1989-1999) in Kobe. A total of 1,580 strains were isolated from domestic and 331 strains from overseas travelers. The results are as follows. 1) Thirteen kinds of enteropathogenic bacteria were isolated from domestic diarrheal cases (6.6%). Salmonella was the most predominant bacteria followed by Campylobacter, Vibrio parahaemolyticus, enteropathogenic Escherichia coli and Shigella. 2) Eleven kinds of enteropathogenic bacteria were isolated from overseas diarrheal travelers (11.6%). The most frequently isolated species was Salmonella, followed by Vibrio parahaemolyticus, Shigella and Plesiomonas shigelloides. 3) Of Salmonella strains isolated from domestic and overseas diarrheal cases, serovar Enteritidis was the most predominant. Other frequent serovars in both cases were Typhimurium, Tennessee, Hadar, Infantis, Blockley and Montevideo. 4) Antibiotics resistant rate of the isolated Salmonella strains was 42.6% for domestic samples and 29.3% for overseas diarrheal cases. In domestic cases. Enteritidis was resistance to streptomycin only and the multiple antibiotic resistance was observed in Typhimurium serovars. In overseas samples, the multiple antibiotic resistance was seen in a few Typhimurium, Anatum and Blockley strains. 5) Among Shigella, S. sonnei was isolated from both domestic and overseas cases. The frequency of acquiring infection was the highest in India, followed by Indonesia, Thailand and Nepal. 6) With reference to the incidence of the members of the genus Vibrio, Aeromonas and Plesiomonas, V. parahaemolyticus were abundant from domestic samples where as V. parahaemolyticus, P. shigelloides, Vibrio cholerae non-O1 and Vibrio cholerae O1 were isolated more frequently from overseas samples. The frequency of acquiring infection was the highest in Thailand, followed by Indonesia and India.

[Perspective of laboratory examination system for infectious disease]

The primary goal of the clinical microbiology laboratory is to provide accurate diagnostic testing and high-quality, rapidly, anytime service at the lowest cost for its customers. In regard to beginning microbiological test as one of emergency test system, the agreement among laboratory staff and the communication with practical conference among clinical divisions are needed, especially about 1. Place and time for receive, 2. Methods of handling and store, 3. Ordering system and information about patients, 4. Selection of items and method, 5. Reporting system and 6. Decision of laboratory staff. As items of microbiological test on this system, smear test, immunoserological test and auto-blood culture equipment are needed. According to the new law of infectious disease, laboratory system should be established in the cases of outbreak. As for the inexperienced cases of import infection, network system of information should be practically used.

Improved preparation of sulfur substituted 3-vinylpyrrole and its application to the syntheses of chuangxinmycin derivatives

Sulfur substituted 3-vinylpyrrole 10 was prepared from 3-thio-acetylpyrrole 9 by alkylation with alkyl halide in the presence of propylene oxide. Functionalized 4-alkylthioindoles were made by Diels-Alder reaction of the 3-vinylpyrrole 10 with dienophiles. Chuangxinmycin analogues were synthesized by using some of the functionalized 4-alkylthioindoles as key intermediates.

[Clinical significance of serum LpA-I levels measured by immunoturbidimetric assay in type 2 diabetes mellitus patients]

Previously, we developed an immunoturbidimetric assay method for lipoprotein A-I(LpA-I) on sera pre-absorbed with anti-apolipoprotein A-II. In the present study, correlations between serum lipoprotein A-I and other serum parameters levels were examined and LpA-I levels were studied in patients with type 2 diabetes mellitus. The serum levels of LpA-I did not correlate with those of diabetic markers such as fasted blood glucose, glycohemoglobin(HbA1c) and fructosamine, but correlated well with the levels of total cholesterol and HDL cholesterol, phospholipids, apolipoprotein A-I and seemed to correlate inversely with arteriosclerosis index. In patients with type 2 diabetes mellitus, LpA-I levels were significantly lower than those in normal subjects. Especially, LpA-I levels of patients with diabetic complications were significantly lower than those in normal subjects and non-complicated diabetic patients. Then, the measurement of LpA-I levels in patients with type 2 diabetes mellitus was considered to be useful for prevention and management of arteriosclerosis.

Evaluation of Immunochromatography Method for Rapid Detection of Shigatoxin

The Shigatoxin detection kit based on the immunochromatography system is commercially available. To obtain the identification result rapidly, we devised the improved method (ICG-Imp) replaced to an original method (ICG). Modification provided that Shigatoxins extracted directly from the strains grown on TSI medium without centrifugation. ICG-Imp was compared with ICG, RPLA and PCR. Comparing with RPLA, the sensitivity, specificity, and concordance rate of Shigatoxin 1 showed 77.5, 100 and 90.5%, respectively on ICG, 93.8, 100 and 97.4%, respectively on ICG-Imp, and 100, 99.1 and 99.5%, respectively on PCR. On the other hand, the patterns of Shigatoxin 2 showed 95.3, 100 and 96.3%, respectively on ICG, 100, 100, and 100%, respectively on ICG-Imp, and 100, 100 and 100%, respectively on PCR. The time required from TSI medium to the final result are 24 h, 30-60 min, 48 h, and 6 h, respectively by ICG, ICG-Imp, RPLA, and PCR. It seems that the ICG-Imp is recommended for the identification by means of the accuracy and rapidness.

Serial pulsed Doppler assessment of pulmonary artery pressure in very low birth-weight infants

We assessed pulmonary artery pressure (PAP) during the early neonatal period in very low birth-weight (VLBW) infants using serial echocardiographic measurements of the ratio of the pulmonary artery acceleration time to the right ventricular ejection time corrected by heart rate [AT:RVET(c)]. Eighty-four VLBW infants weighing less than 1,500 g were examined using serial color Doppler echocardiography from 3 hours to day 7 after birth. The AT:RVET(c) of infants born after 30 weeks of gestation showed a rapid, significant increase during the early neonatal period, whereas those of the groups born at less than 30 weeks showed no significant increase before day 14. At 24 hours after birth, the AT:RVET(c) values of VLBW infants did not correlate well with either the ratio of the right preejection period to the right ventricular ejection time on M-mode echocardiography or the pressure gradient between the right ventricle and the right atrium, as estimated by tricuspid regurgitation on pulsed Doppler echocardiography. The AT:RVET(c) value for the chronic lung disease (CLD) group did not differ significantly from that for the oxygen-dependent group at any assessment point. During the early neonatal period, the AT:RVET(c) of VLBW infants, as calculated by pulsed Doppler echocardiography, differed with their gestational age and did not appear to correlate well with PAP. Our data also suggest that AT:RVET(c) values may not be a good predictor of the subsequent occurrence of CLD in VLBW infants.

Ca2+ dynamics at the frog motor nerve terminal

Rises in free [Ca2+]i in response to various tetanic stimuli (Ca2+ transient) in frog motor nerve terminals were measured by recording fluorescence changes of Ca2+ indicators and analyzed in relation to short-term synaptic plasticity. Ca2+ transients reached a plateau after 10-20 impulses at 100 Hz and decayed in a three-exponential manner, in which the fast component was predominant. The plateau and fast component of the Ca2+ transient were elevated infralinearly with an increase in tetanus frequency. Computer simulation showed that the Ca2+ transients estimated from fluorescence changes faithfully reflect the true changes in [Ca2+]i except for the initial 20 ms. A slow Ca2+ chelator, EGTA, loaded into the nerve terminal, decreased the magnitude of both the fast and slow components of facilitation of transmitter release and the time constant of the former. A fast Ca2+ chelator, BAPTA, decreased the magnitude of fast facilitation but slightly increased its time constant. These results suggest that Ca2+ transients in the frog motor nerve terminals are primarily caused by Ca2+ entry and are dissipated by three components, in which the rate of the fast component is equivalent to that of free Ca2+ diffusion. The residual Ca2+ in the nerve terminals after stimulation accounts for the fast component of facilitation.

Glycated apolipoprotein A-I assay by combination of affinity chromatography and latex immunoagglutination

The degree of glycation of plasma apolipoprotein A-I was measured by a combination of gel filtration, boronate affinity chromatography and latex immunoagglutination. The plasma concentrations of apolipoprotein A-I determined by this combination method (y) correlated well with those determined by turbidimetric immunoassay (x) (y=1.12x + 1.9, r=0.964). The inter- and intra-assay coefficients of variation in the glycated apolipoprotein A-I assay were 4.1-5.0% and 4.0-4.4%, respectively. Interference from plasma glucose at concentrations up to 55.1 mmol/L was eliminated by gel filtration. Labile glycated apolipoprotein A-I did not interfere with the measurement of glycated apolipoprotein A-I. Reference values for glycated apolipoprotein A-I were determined to be 2.4-4.0% (n=140), with no significant difference between men and women. The mean concentration of plasma glycated apolipoprotein A-I in patients with uncontrolled diabetes mellitus (5.11%) was significantly higher than in normal subjects (3.12%, P<0.001). The method is simple, rapid and highly sensitive for determination of the glycation level of plasma apolipoprotein A-I.

[Treatment by corticosteroid and plasma exchange in 5 cases of renal cholesterol embolic disease]

Cholesterol arterial embolization is a systemic disease resulting from cholesterol crystal embolization to multiple organs, including the kidney, skin, brain, eye, gastrointestinal tract and extremities. In general, it is associated with high morbidity and mortality, but no optimal treatment has yet been developed. In this paper, we report five patients with cholesterol atheroembolic renal failure. In three of the five patients, combined therapy with corticosteroids and plasma exchange was performed. The three patients survived. On the other hand, the two remaining patients died of multifactorial causes. In this report, the literature on steroid therapy for cholesterol atheroembolic renal disease is reviewed and the efficacy of combined therapy by use of corticosteroids and plasma exchange is evaluated.

[A case of Chinese herbs nephropathy in which the progression of renal dysfunction was slowed by steroid therapy]

The patients was a 43-year-old woman whose chief complaints were nausea and heaviness of the heads. There was a history of toxemia of pregnancy. The patient had previously taken Tenshin Tokishigyaku-ka-goshuyu-shokyo-to for two years because of cold sensitivity. Fever, thirst, and loss of appetite developed from approximately 18 months after she started treatment with the Chinese herbal preparation, and she presented at our outpatient clinic 2.5 years later. On initial examination, deterioration of renal function was evident and the serum creatinine level was 3.4 mg/dl. A renal biopsy specimen showed marked interstitial fibrosis without inflammatory cell infiltration, leading to the diagnosis of Chinese herbs nephropathy (CHN). Steroid therapy was started on the 36th hospital day after a sharp rise in the serum creatinine level to 5.1 mg/dl. This resulted in the rapid improvement of renal function and reduction of the serum creatinine to 2.6 mg/dl by 8 weeks after the initiation of treatment. In a study on the use of steroids for patients with progressive moderate renal dysfunction caused by Chinese herbs, Vanherweghem et al. reported that the progression of renal failure was appreciably slowed in patients given steroids when compared with the control group. We were also able to slow the progression of renal dysfunction in our patient by steroid therapy, although the prognosis of CHN is generally considered to be very poor.

Repair of leaking postinfarction ventricular septal defect under circulatory arrest via left thoracotomy

We treated a 60-year-old woman for postinfarction ventricular septal defect (VSD) and closed it by the infarction exclusion method. Postoperatively she was complicated by Candida sternal mediastinitis and residual shunt of VSD. After her sternal infection came under control we repaired the leaking VSD via left thoracotomy under hypothermic circulatory arrest. She recovered well and repair of the leaking VSD under circulatory arrest via left thoracotomy seemed to be a safe and promising alternative for VSD repair.

A new concise synthesis of arcyriacyanin A and its unique inhibitory activity against a panel of human cancer cell line

The nucleophilic addition reaction of N-tosyl-4-oxo-4,5,6,7-tetrahydroindole (12) with the lithium salt of 1-methoxyindole (5), followed by dehydration with 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ) gave the derivative of 2,4'-bi-1H-indole (9) which provides a new concise synthetic method of an indole pigment of the slime mould, arcyriacyanin A. The compound was first demonstrated here to have unique inhibitory activity to a panel of human cancer cell lines and to inhibit protein kinase C and protein tyrosine kinase.

A complete deficiency of coagulation factor XIII A-subunit due to a novel compound heterozygote of Ser 413 Leu missense and an nt 389 (ins G) frameshift mutation

Coagulation factor XIII consists of two A- and two B-subunits, and either gene mutation can cause a complete deficiency. In a newborn patient with persistent bleeding from the umbilical cord stump, the plasma A-subunit protein was not detectable. Direct PCR sequencing revealed an nt 389 (ins G) frameshift mutation in exon 4 resulting in a new stop codon and a Ser 413 Leu missense mutation in exon 10 in either allele. His mother and father were heterozygous for the nt 389 (ins G) and the Ser 413 Leu, respectively, with about 50% reduction of the plasma A-subunit proteins. In all family members examined only those with either mutation showed the reduced subunit A protein levels. Thus, this complete deficiency of factor XIII was due to a novel compound heterozygous mutation in the A-subunit gene.

[In vitro antibacterial activities of carbapenems against clinical isolates]

Antibacterial activities of four carbapenems, imipenem, panipenem, meropenem, and biapenem, were determined using 353 strains belonging to 18 bacterial species which were isolated from clinical materials at Ehime University Hospital. The MIC values of these carbapenems against MRSA were widely distributed between 0.1 and 100 micrograms/ml, and MIC90 values of these 4 carbapenems were 25-50 micrograms/ml. Any of these carbapenems prevented the bacterial growth of enterobacteriaceae of 8 bacterial species excluding S. macrescens at concentrations of 1 microgram/ml or less. The MIC values against P. aeruginosa showed relatively wide distribution, being 0.39-25 micrograms/ml for imipenem, 0.2-25 micrograms/ml for panipenem, 0.1-12.5 micrograms/ml for meropenem, and 0.2-12.5 micrograms/ml for biapenem. From those results, it was confirmed that any of the carbapenems tested had a wide antibacterial spectrum and strong antibacterial activities.

Structure of mouse calpastatin isoforms: implications of species-common and species-specific alternative splicing

Mouse calpastatin cDNAs were cloned by the method of RT-PCR using RNA isolated from myoblast C2C12 cells. Nucleotide sequencing of the isolated clones revealed an in-frame ATG codon upstream of the previously assigned translation initiation methionine. Except for the N-terminal segment, the new translatable region (domain XL) was similar to the sequence of bovine calpastatin in which domain XL was first identified. Among the isolated mouse calpastatin cDNA clones, three isoforms (mCS-a, mCS-b, and mCS-c) were identified. In domain L, mCS-b had a deletion of the region corresponding to exon 3 of the human calpastatin gene. RT-PCR analyses of various mouse tissues revealed that mCS-b was the major form and that the content of mCS-a, nondeleted form, was 5-10% in tissues including skeletal muscle, liver, brain, etc. and about 30% in the myoblast C2C12 cells. Unlike human and rat cDNAs, no other deletions were detected in mouse calpastatin domain L. Isolation of the cDNA clone of mCS-c, which lacked regions corresponding to exons 3 and 12, was obtained by chance because its expression level was under the detectable level in the mouse tissues and even in C2C12 cells.