Acute renal failure due to adenovirus-associated obstructive uropathy and necrotizing tubulointerstitial nephritis in a bone marrow transplant recipient

Management of post-transplant complications caused by severe adenoviral infection remains a major therapeutic challenge. A 17-year-old male who had undergone bone marrow transplantation for the treatment of acute lymphoblastic leukemia developed complete anuria following hemorrhagic cystitis 34 days after the transplant procedure. The computed tomogram scan revealed bilateral hydronephrosis, indicating acute renal failure because of obstructive uropathy. The emergency procedure of percutaneous nephrostomy caused massive bleeding in the left kidney, which eventually required a nephrectomy. Adenovirus-positive severe necrotizing tubulointerstitial nephritis was the histopathological diagnosis. Post-transplant acute renal failure because of hydronephrosis, which could be complicated by adenovirus-induced renal parenchymal disease, is of great concern and may cause significant problems with interventional treatment.

Potent and selective ET-A antagonists. 2. Discovery and evaluation of potent and water soluble N-(6-(2-(aryloxy)ethoxy)-4-pyrimidinyl)sulfonamide derivatives

In the preceding article,(1) we outlined the discovery and structure-activity relationship of a potent and selective ET(A) receptor antagonist 1 and its related compounds. Metabolites of 1 having potent selective ET(A) receptor antagonist activity were identified. This study suggested the metabolic pathways of 1 were considerably affected by species. Consequently, structural modification of 1 intended to improve the complexity of the metabolic pathway, and water solubility was performed. The subsequent introduction of a hydroxyl group into the tert-butyl moiety of 1 led to the discovery of our new clinical candidate, 6b, which showed a higher water solubility, a uniform metabolic pathway among species, and very high affinity and selectivity for the human ET(A) receptor (K(i) for ET(A) receptor: 0.015 +/- 0.004 nM; for ET(B) receptor: 41 +/- 21 nM).

Potent and selective ET-A antagonists. 1. Syntheses and structure-activity relationships of N-(6-(2-(aryloxy)ethoxy)-4-pyrimidinyl)sulfonamide derivatives

Modifications to the ET(A/B) mixed type compounds 1 (Ro. 46-2005) and 2 (bosentan) were performed. Introduction of a pyrimidine group into 1 resulted in a dramatic increase in affinity for the ET(A) receptor, and the subsequent optimization of substituents on the pyrimidine ring led us to the discovery of N-(6-(2-((5-bromo-2-pyrimidinyl)oxy)ethoxy)-5-(4-methylphenyl)-4-pyrimidinyl)-4-tert-butylbenzenesulfonamide (7k), which showed an extremely high affinity for the human cloned ET(A) receptor (K(i) = 0.0042 +/- 0.0038 nM) and an ET(A/B) receptor selectivity up to 29 000 (K(i) = 130 +/- 50 nM for the human cloned ET(B) receptor). The compound was designed on the hypothesis that the hydrogen atom of the hydroxyl group in 1 and 2 played a role not as a proton donor but as an acceptor in the possible hydrogen bonding with Tyr129. Since the incorporation of a pyrimidinyl group into the hydroxyethoxy side chain of the nonselective antagonist (1) dramatically enhanced both the ET(A) receptor affinity and selectivity, and since similar results were obtained from the benzene analogues, we put forward the hypothesis that a "pyrimidine binding pocket" might exist in the ET(A) receptor.

Comparison of intracytoplasmic sperm injection for inbred and hybrid mice

We compared the results of intracytoplasmic sperm injection (ICSI) that leads to full term development of hybrid (B6C3F1 and B6D2F1) and inbred (C57BL/6) mouse embryos. Although fertilization and pre-implantation development of C57BL/6 eggs were similar to those of F1 hybrid eggs, post-implantation development of the embryos from C57BL/6 females was significantly poorer than those of the eggs from hybrid females. Reciprocal crosses of C57BL/6 and B6C3F1 gametes revealed that the low rate of post-implantation development of C57BL/6 embryos was due to oocyte factor(s), rather than the sperm factor.

Apoptosis, rather than oncosis, is the predominant mode of spontaneous death of isolated adult rat cardiac myocytes in culture

A number of isolated adult cardiomyocytes dies within a few days of culture and the mode of death has recently been suggested to be apoptosis, based on its association with the appearance of DNA fragmentation. However, morphological evidence is still lacking and precise analysis, including quantification, has not been performed. Adult rat ventricular cardiomyocytes isolated by enzymatic dissociation were incubated for 7 days in a serum-free medium (the rapid attachment model) and after various incubation periods, both attached and floating cells were counted and classified based on combined criteria of morphology and membrane permeability (dye exclusion): type 1, rod cells with intact membranes; type 2, non-rod cells with intact membranes; and type 3, non-rod cells with ruptured membranes. The number of both rod-shaped and dye-excluding cells decreased with the incubation period. After 7 days culture, the number of residual cells decreased to 12% of the initial value. Electron microscopy identified type 1 cells as viable, type 2 cells as viable or apoptotic, and type 3 as undergoing oncosis (primary necrosis) or secondary post-apoptotic necrosis. Ultrastructural morphometry revealed that oncotic cell death occurred predominantly during the early phase of culture whereas the more abundant apoptotic cell death occurred throughout the culture period. In conclusion, although both apoptotic and oncotic death occur in the natural course of adult rat cardiomyocytes in short-term culture, apoptosis is more predominant. Because of the high incidence of spontaneous cell death predominantly via apoptosis, this information is important for the interpretation of studies using this cell type in culture.

Dynamic process of apoptosis in adult rat cardiomyocytes analyzed using 48-hour videomicroscopy and electron microscopy: beating and rate are associated with the apoptotic process

Dynamic process of apoptosis has not been elucidated in adult rat cardiomyocytes. Soluble Fas ligand (0.1 microg/ml) in the presence of actinomycin D (0.05 microg/ml) induced apoptosis in cultured adult rat cardiomyocytes, as documented by activated caspase-3, DNA fragmentation, and apoptotic ultrastructure. In the present model, we observed 60 adult cardiomyocytes with a normal rod shape under a real-time videomicroscope continuously for 48 hours. Seventeen cells (28%) were unchanged and 7 cells (12%) showed oncosis (so-called necrosis) in which no beating was evident. In the remaining 36 cells (apoptosis, 60%), a slow beating (17 +/- 3/min) was initiated 16 +/- 1 hours later. Approximately 1 hour later, the rod cells showed long-axial shortening as bone- or club-like, or square-shaped, accompanied with faster beating rates (35 +/- 7/min). In 29 cells (type A1 and A2), marked shrinkage occurred; the cellular shape became almost completely round with a smooth surface and the beating ceased 3.0 +/- 0.4 hours later. Then, smooth budding appeared 0.6 +/- 0.2 hours later. Apoptotic bodies were found in 8 cells 10 +/- 4 hours later (type A1, 13%) but not in 21 cells (type A2, 35%). In the other 7 cells (type A3, 12%), the cell surface became rough 8 +/- 3 hours later and the beating ceased. Maximal beating rate was greatest in type A1 (72 +/- 26/min) and greater in type A2 (29 +/- 5/min) than in type A3 (10 +/- 2/min). Electron microscopy confirmed apoptotic ultrastructure even in the cardiomyocytes with bone-, club-like, or square shapes, suggesting that type A3 as well as A1 and A2 is also under apoptotic process. A caspase inhibitor, zVAD.fmk, blocked beating, apoptotic morphology, and DNA fragmentation, indicating these depended on caspase activation. In the caspase-dependent apoptotic process of cultured adult cardiomyocytes, beating and the following deformity of the cellular edges were the initial signs and the rate of beating was related with the subsequent three different processes of apoptosis.

Disruption of imprinted expression of U2afbp-rs/U2af1-rs1 gene in mouse parthenogenetic fetuses

The present study shows that the U2afbp-rs gene, a paternally expressed imprinted gene, is activated and expressed in a biallelic manner from maternal alleles in parthenogenetic mouse fetuses on day 9.5 of gestation. The mean expression was detected to be 88% (31-134%) of that in control biparental fetuses, using real-time quantitative reverse transcription and polymerase chain reaction. This disrupted expression of the gene was associated with changes in the chromatin structure but not with the methylation pattern in the regulation region. The present results show that parental specific expression of imprinted genes is not always maintained in uniparental embryos. This suggests that both parental genomes are necessary to establish parental specific expression of the U2afbp-rs gene.

Cutting edge: IL-18-transgenic mice: in vivo evidence of a broad role for IL-18 in modulating immune function

IL-18 has been shown to be a strong cofactor for Th1 T cell development. However, we previously demonstrated that when IL-18 was combined with IL-2, there was a synergistic induction of a Th2 cytokine, IL-13, in both T and NK cells. More recently, we and other groups have reported that IL-18 can potentially induce IgE, IgG1, and Th2 cytokine production in murine experimental models. Here, we report on the generation of IL-18-transgenic (Tg) mice in which mature mouse IL-18 cDNA was expressed. CD8+CD44high T cells and macrophages were increased, but B cells were decreased in these mice while serum IgE, IgG1, IL-4, and IFN-gamma levels were significantly increased. Splenic T cells in IL-18 Tg mice produced higher levels of IFN-gamma, IL-4, IL-5, and IL-13 than control wild-type mice. Thus, aberrant expression of IL-18 in vivo results in the increased production of both Th1 and Th2 cytokines.

Axial length and refractive error in X-linked retinoschisis

PURPOSE

To examine the relationship between axial length and refractive error in patients with X-linked retinoschisis.

DESIGN

To determine whether the hypermetropia frequently found in patients with X-linked retinoschisis is axial hypermetropia.

METHODS

The axial length and refractive error were measured in 29 right eyes of 29 patients. The patients were divided into two groups: a juvenile group with ages <13 years (12 eyes) and an adult group with ages > or =13 years (17 eyes). The axial length of the right eye of 30 adult men without eye diseases whose refractive error ranged from +/- 1.0 diopter served as controls.

RESULTS

In the adult patient group, the refractive error was significantly more hypermetropic and the axial length was significantly shorter than was the normal adult group (P <.001).

CONCLUSION

These results strongly suggest that the hypermetropia in patients with X-linked retinoschisis is axial hypermetropia.

[Inflammatory endotracheal polyp associated with lung cancer treated by high-power diode laser]

A 74-year-old man was admitted to our department for surgery of light lung cancer (c-T1N0 M0 stage IA). Preoperative bronchoscopy revealed a smooth-surfaced polypoid lesion about 3 mm in diameter in the left main bronchus. Pathological findings of the biopsied specimen revealed inflammatory granulation tissue. Right upper lobectomy and lymph node dissection was performed and the pathological diagnosis was squamous cell carcinoma of the lung with no lymph node metastasis (p-T1N0M0 stage IA). Bronchoscopy after 2 and 5 month revealed no change of the polypoid lesion and the biopsied specimen revealed no malignancy. The polypoid lesion was identified microscopically as inflammatory polyp. Therefore, the polypoid lesion was treated with a new high power diode laser system (DIOMED 25, OLYMPUS). Bronchoscopy after 10 month showed complete disappearance of the polypoid lesion.

Expression of neural cell adhesion molecule in pancreatic cancer

Neural cell adhesion molecule (NCAM) has been found to be a significant factor for survival in various solid tumors. In the present study, we examined the expression of NCAM in exocrine tumors of the pancreas by immunohistochemistry, using two monoclonal antibodies against NCAM and polysialic acid (MAB735). Expression of NCAM was seen mainly in the cytoplasm of the following cells: regenerating duct cells among neoplastic tissue, hyperplastic islet cells, intrapancreatic nerves and ganglia, as well as tumor cells. There was no reactivity with MAB735. We found a significant correlation between intense NCAM expression (i.e., expression in more than 50% of all tumor cell mass) and survival rates in tubular adenocarcinoma, particularly moderately differentiated tumors (p < 0.05). There was no statistically significant relation between NCAM reactivity and tumor stage or any of the clinicopathologic parameters described by the Japan Pancreas Society (p > 0.05). We conclude that the expression of NCAM in tubular adenocarcinoma of the pancreas, particularly in moderately differentiated tumors, has a significant impact on the overall patient survival.

Application of the piezo-micromanipulator for injection of embryonic stem cells into mouse blastocysts

Microinjection of embryonic stem (ES) cells into mouse blastocysts is one of the most important techniques for production of knockout or transgenic mice. However, skillful manipulation techniques and tremendous effort are required for this method. To overcome this difficulty, we applied a piezo-micromanipulator (PMM), which has been used for intracytoplasmic sperm injection in mice and production of cloned mice, for the injection of ES cells into blastocysts. When ES cells were injected by using a conventional method, 91% of the blastocysts were manipulated successfully. Using the PMM significantly (P < 0.01) increased the success rate of ES injection to 97%. The number of embryos manipulated in an hour increased from 9.7 embryos with the conventional method to 27.0 embryos with the PMM method. The injected ES cells did not show any detrimental effects due to a pulse from the PMM. After embryo transfer of the manipulated blastocysts, 39% of the newborns were chimeric mice with the conventional method, whereas 42% of the neonates were chimeric after the PMM method. These results indicate that microinjection of the ES cells into blastocysts is more efficient by the PMM method than the conventional method.

[A case of panpleuropneumonectomy for diffuse pleural mesothelioma]

A 58-year-old man was admitted to our hospital because of chest pain and dyspnea on July 15, 1999. A chest X-ray showed left pleural effusion, and a chest CT revealed left pleural effusion and diffuse pleural thickening. Because pleural fluid cytology and percutaneous needle pleural biopsy were negative for malignancy, thoracoscopic biopsy was performed on July 28. The biopsied specimen revealed malignant pleural mesothelioma (epithelial type). An operation was performed on August 16. First, mediastinal lymph node dissection was performed and we identified that there was no lymph node metastasis by frozen section diagnosis. Then panpleuropneumonectomy with combined resection of the diaphragm and pericardium was performed.

Alteration of conformation and dynamics of bacteriorhodopsin induced by protonation of Asp 85 and deprotonation of Schiff base as studied by 13C NMR

According to previous X-ray diffraction studies, the D85N mutant of bacteriorhodopsin (bR) with unprotonated Schiff base assumes a protein conformation similar to that in the M photointermediate. We recorded (13)C NMR spectra of [3-(13)C]Ala- and [1-(13)C]Val-labeled D85N and D85N/D96N mutants at ambient temperature to examine how conformation and dynamics of the protein backbone are altered when the Schiff base is protonated (at pH 7) and unprotonated (at pH 10). Most notably, we found that the peak intensities of three to four [3-(13)C]Ala-labeled residues from the transmembrane alpha-helices, including Ala 39, 51, and 53 (helix B) and 215 (helix G), were suppressed in D85N and D85N/D96N both from CP-MAS (cross polarization-magic angle spinning) and DD-MAS (dipolar decoupled-magic angle spinning) spectra, irrespective of the pH. This is due to conformational change and subsequent acquisition of intermediate time-range motions, with correlation times in the order of 10(-)(5) or 10(-)(4) s, which interferes with proton decoupling frequency or frequency of magic angle spinning, respectively, essential for an attempted peak-narrowing to achieve high-resolution NMR signals. Greater changes were achieved, however, at pH 10, which indicate large-amplitude motions of transmembrane helices upon deprotonation of Schiff base and the formation of the M-like state in the absence of illumination. The spectra detected more rapid motions in the extracellular and/or cytoplasmic loops, with correlation times increasing from 10(-)(4) to 10(-)(5) s. Conformational changes in the transmembrane helices were located at helices B, G, and D as viewed from the above-mentioned spectral changes, as well as at 1-(13)C-labeled Val 49 (helix B), 69 (B-C loop), and [3-(13)C]Ala-labeled Ala 126 (D-helix) signals, in addition to the cytoplasmic and extracellular loops. Further, we found that in the M-like state the charged state of Asp 96 at the cytoplasmic side substantially modulated the conformation and dynamics of the extracellular region through long-distance interaction.

Ganglioside GD3 and its mimetics induce cytochrome c release from mitochondria

Ganglioside GD3 induced the release of cytochrome c from isolated rat liver mitochondria. This process was completely prevented by cyclosporin A and partially prevented by a cysteine protease inhibitor, n-acetyl-leu-leu-norleucinal. Cyclosporin A is a potent inhibitor of the permeability transition pore, whereas n-acetyl-leu-leu-norleucinal has no effect on this pore. These results indicate that the release of cytochrome c from mitochondria requires both the opening of the permeability transition pore and a cysteine protease inhibitor-sensitive mechanism. Gangliosides GD1a, GD1b, GT1b, and GQ1b along with the synthetic GD3 mimetics TMS-42 and CI-22, which are glycerophospholipids carrying a disialo residue, also induced cytochrome c release. In contrast, gangliosides GM1, GM2, and GM3 did not induce cytochrome c release. These results indicate that two sialo residues must play an important role in the induction of cytochrome c release by gangliosides.

The paternal methylation imprint of the mouse H19 locus is acquired in the gonocyte stage during foetal testis development

BACKGROUND

Germline-specific differential DNA methylation that persists through fertilization and embryonic development is thought to be the 'imprint' distinguishing the parental alleles of imprinted genes. If such methylation is to work as the imprinting mechanism, however, it has to be reprogrammed following each passage through the germline. Previous studies on maternally methylated genes have shown that their methylation imprints are first erased in primordial germ cells (PGCs) and then re-established during oocyte growth.

RESULTS

We have examined the timing of the reprogramming of the paternal methylation imprint of the mouse H19 gene during germ cell development. In both male and female PGCs, the paternal allele is partially methylated whereas the maternal allele is unmethylated. This partial methylation is completely erased in the female germline by entry into meiosis, establishing the oocyte methylation pattern. In the male germline, both alleles become methylated, mainly during the gonocyte stage, establishing the sperm methylation pattern.

CONCLUSION

The paternal methylation imprint of H19 is established in the male germline and erased in the female germline at specific developmental stages. The identification of the timings of the methylation and demethylation should help to identify and characterize the biochemical basis of the reprogramming of imprinting.

[A case of congenital cystic adenomatoid malformation of the lung in a 4-year-old child]

A case of congenital cystic adenomatoid malformation (CCAM) of the lung is reported. A 3-year-old boy was admitted for elevation of infiltrative shadow in the right lower lung field on a chest X-ray. The clinical diagnosis was emphysematous bullae with inflammation. After 6 months, he had recurrent infected bullae, and was admitted. He received chemotherapy with antibiotics prior to the operation. Right lower lobectomy was performed on February 2, 1998. The resected lung was composed of multiple cysts with thin wall measuring 10-60 mm in diameter. The histological examination of specimen revealed CCAM (Stocker type I), which is rare in this age. The patient has been well for 16 months postoperatively.

Endomyocardial biopsy findings in patients with atrioventricular block in the absence of apparent heart disease

The purpose of this study was to examine the histopathological findings of right ventricular endomyocardial biopsies from ten patients less than 60 years of age (47 +/- 9.8 (mean +/- SD) years) with documented atrioventricular block but without apparent heart disease. They underwent electrophysiological testing, echocardiography, coronary angiography, and right ventricular endomyocardial biopsy. Biopsy specimens were assessed for morphologic changes in myocyte diameter, fibrosis, disarray, and degeneration. Electrophysiological testing demonstrated atrioventricular nodal block in 2, intra-His bundle block in 2, and infra-His bundle block in 6 patients. Histology revealed evidence of myocardial fibrosis with either myocyte hypertrophy or disarray in 7 of the 10 patients. The results of electrophysiological testing did not correlate with the histopathological findings or severity. In one patient, heart failure appeared during the follow-up period. We conclude that patients with atrioventricular block of unknown etiology have histological abnormalities of the ventricular endomyocardium in addition to the conduction system disturbances. We consider such cases as constituting one of the disease groups of cardiomyopathy, and suggest that it is necessary to follow up the clinical course in these patients.

Molecular cloning and characterization of a novel bacteriophage-associated sialidase

Bacteriophage 63D, previously isolated from sewage, is associated with alpha-2,8-linked polysialic acid degrading activity. We cloned a DNA fragment containing the sialidase gene from a 63D phage genomic library and the enzyme was functionally expressed in Escherichia coli. Determination of the nucleotide sequence of the fragment revealed that it contained one open reading frame (ORF) coding for a 108-kDa polypeptide consisting of 984 amino acid residues. The fragment had promoter sequences similar to the E. coli consensus promoters for sigma70. The deduced amino acid sequence of the central region of the ORF showed homology to those of phages K1F (51.6% identity) and PK1E (51.7% identity) endosialidases. Two Asp-box motifs that are widely found in sialidases were conserved. Purification of the soluble enzyme from lysed culture broth of infected E. coli yielded a 90-kDa protein upon SDS polyacrylamide gel electrophoresis, suggesting that the primary translational product is processed to the mature 90-kDa protein. The molecular mass of the enzyme was determined as 360 kDa by gel filtration, indicating that the native enzyme was probably a tetramer of identical 90-kDa subunits.

Continuous production of sialyllactose from colominic acid using a membrane reactor

Continuous production of sialyllactose, as a typical sialylsaccharide, was examined using a membrane reactor. The synthesis of sialyllactose through the transfer reaction catalyzed by neuraminidase, has been reported to be a suitable process for industrial production, but it still has drawbacks such as a low yield, high enzyme cost, and hydrolysis by the enzyme of sialyllactose formed. We attempted to solve these problems by utilizing an appropriate membrane reactor system. We first investigated the effects of various reaction conditions on sialyllactose productivity, and found that the productivity was independent of the enzyme concentration and reaction temperature but dependent on the substrate and buffer concentrations and the hydraulic retention time (HRT). We then selected a suitable membrane that allowed sialyllactose to permeate but rejected the substrate and enzyme. Finally, we constructed a membrane reactor system with a cut-off molecular weight of 3000 and applied it to continuous sialyllactose production from colominic acid at an HRT of 80 min. Using substrate concentration of 25 g/l the system performed with a high level of productivity and gave a good yield, while maintaining high transfer ratio of 4-5% over a 160-h test period.