Can Individuals with Suboptimal Antibody Responses to Conventional Antiviral Vaccines Acquire Adequate Antibodies from SARS-CoV-2 mRNA Vaccination?

In Japan, healthcare workers (HCWs) are vaccinated against measles, rubella, chickenpox, mumps, and hepatitis B to prevent nosocomial infection; however, some do not produce sufficient antibodies ("suboptimal responders"). This study compared immune responses to a severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2 mRNA) vaccine among HCWs with normal and suboptimal responses to conventional vaccines. In this prospective cohort study, 50 HCWs received two doses of BNT162b2 mRNA vaccine 3 weeks apart. SARS-CoV-2 anti-spike antibodies were measured 11 times, starting before the first vaccination and ending 5 months after the second vaccination. Antibody titers of four suboptimal and 46 normal responders were compared. SARS-CoV-2 neutralizing antibody activity was measured twice in suboptimal responders, 1 week/1 month and 5 months after the second vaccination. The SARS-CoV-2 anti-spike antibody was detectable in the samples from suboptimal and normal responders at each timepoint after vaccination. Suboptimal responders exhibited SARS-CoV-2 neutralizing antibody activity 1 week/1 month as well as 5 months after the second vaccination; however, activity was slightly reduced at 5 months. Our findings show that suboptimal responders do acquire adequate SARS-CoV-2 anti-spike and SARS-CoV-2 neutralizing antibodies from vaccination to prevent SARS-CoV-2. SARS-CoV-2 mRNA vaccines should thus be recommended for both normal and suboptimal responders to conventional vaccines.

Bone marrow-derived NGFR+ cells regulate arterial remodeling and those poor mobilizations in peripheral blood in acute coronary syndrome predicts plaque progression at the non-targeted lesion

Background

In our previous 5-year cohort study, we demonstrated that low gene expression of nerve growth factor receptor (NGFR) in peripheral leucocytes in acute coronary syndrome (ACS) predicted repetitive coronary interventions at the de novo lesions. An NGFR-positive cell has been demonstrated to reside in bone marrow (BM) stromal fraction and to be increased in peripheral blood mononuclear cell (MNCs) fraction in patients with ischemic heart disease.

Purpose

To investigate whether the BM-NGFR+ cell is associated with arterial remodeling and the relationship between the levels of peripheral NGFR+ cells after ACS and coronary plaque progression in an experimental and prospective clinical study.

Methods and results

In an experimental study, 8-week-old C57B6/J wild type male mice were subjected to irradiation with 9.6 Gy and transplantation with BM (BMT) isolated from GFP-transgenic NGFR wild type (WT) or knock-out (KO) mice at day 1. Four weeks after BMT, the right carotid artery was ligated for 4 weeks. Induced neointimal area was increased (p<0.05), where cells under apoptosis were decreased (p<0.05) in NGFR-KO-BMT group compared to WT-BMT group (n=4). NGFR+ cells were not detected in wild type sham-operated artery, whereas in the ligated artery in WT-BMT group NGFR+ cells assembled in the developed neointima and exclusively presented double positive with GFP, but absent in NGFR-KO-BMT group (p<0.05, n=4). In a clinical study, thirty patients with ACS who underwent primary percutaneous coronary intervention (PCI) were enrolled. The peripheral blood sample was collected on days 0, 3 and 7, and 9 months follow-up and the number of NGFR+MNCs were measured by flowcytometric analysis. The plaque volume at non-targeted coronary lesion (non-TL:>5 mm proximal or distal to the implanted stents) were quantitatively analysed using gray-scale intravascular ultrasound (IVUS) and Q-IVUS™ software at the acute phase and 9 months follow-up. The number of NGFR+MNCs in peripheral blood was 1.5-fold increased at day 3 (0.064±0.056%) compared to day 0 (0.042±0.030%) (p<0.05). The change in normalized total plaque volume (TAVN) at non-TL at 9 months was negatively correlated with the number of NGFR+MNCs at day 0 (r=−0.51), day 3 (r=−0.51) and 9 months (r=−0.59) after ACS (p<0.05). Multiple regression analysis showed that NGFR+MNCs at day 0 (β=−0.48, p=0.01) and CRP (β=−0.53, P<0.01) are independent factors associating with TAVN change at non-TL at 9 months, regardless of LDL-cholesterol control level. ROC analysis revealed that NGFR+MNCs <0.049 at day 0 predicted the increase of TAVN with AUC 0.78; sensitivity 0.82 and specificity 0.67.

Conclusions

Bone marrow-derived peripheral NGFR+ cells negatively regulate arterial remodeling through appropriate apoptosis of neointimal cells and the peripheral level of NGFR+ cells in ACS predicts plaque progression at the non-targeted lesion.

Funding Acknowledgement

Type of funding source: Public grant(s) – National budget only. Main funding source(s): KAKENHI

The surface composition of asteroid 162173 Ryugu from Hayabusa2 near-infrared spectroscopy

The near-Earth asteroid 162173 Ryugu, the target of the Hayabusa2 sample-return mission, is thought to be a primitive carbonaceous object. We report reflectance spectra of Ryugu's surface acquired with the Near-Infrared Spectrometer (NIRS3) on Hayabusa2, to provide direct measurements of the surface composition and geological context for the returned samples. A weak, narrow absorption feature centered at 2.72 micrometers was detected across the entire observed surface, indicating that hydroxyl (OH)-bearing minerals are ubiquitous there. The intensity of the OH feature and low albedo are similar to thermally and/or shock-metamorphosed carbonaceous chondrite meteorites. There are few variations in the OH-band position, which is consistent with Ryugu being a compositionally homogeneous rubble-pile object generated from impact fragments of an undifferentiated aqueously altered parent body.

The role of the extracellular matrix in primary myelofibrosis

Primary myelofibrosis (PMF) is a myeloproliferative neoplasm that arises from clonal proliferation of hematopoietic stem cells and leads to progressive bone marrow (BM) fibrosis. While cellular mutations involved in the development of PMF have been heavily investigated, noteworthy is the important role the extracellular matrix (ECM) plays in the progression of BM fibrosis. This review surveys ECM proteins contributors of PMF, and highlights how better understanding of the control of the ECM within the BM niche may lead to combined therapeutic options in PMF.

Restoration of MYC-repressed targets mediates the negative effects of GM-CSF on RUNX1-ETO leukemogenicity

GM-CSF signaling regulates hematopoiesis and immune responses. CSF2RA, the gene encoding the α subunit for GM-CSF, is significantly downregulated in t(8;21) (RUNX1-ETO or RE) leukemia patients, suggesting that it may serve as a tumor suppressor. We previously reported that GM-CSF signaling is inhibitory to RE leukemogenesis. Here we conducted gene expression profiling of primary RE hematopoietic stem/progenitor cells (HSPCs) treated with GM-CSF to elucidate the mechanisms mediating the negative effects of GM on RE leukemogenicity. We observed that GM treatment of RE HSPCs resulted in a unique gene expression profile that resembles primary human cells undergoing myelopoiesis, which was not observed in control HSPCs. Additionally we discovered that GM-CSF signaling attenuates MYC-associated gene signatures in RE HSPCs. In agreement with this, a functional screen of a subset of GM-CSF-responsive genes demonstrated that a MYC inhibitor, MXI1, reduced the leukemic potential of RE HSPCs and t(8;21) AML cells. Furthermore, MYC knockdown and treatment with the BET inhibitor JQ1 reduced the leukemic potential of t(8;21) cell lines. Altogether, we discovered a novel molecular mechanism mediating the GM-CSF-induced reduction in leukemic potential of RE cells, and our findings support MYC inhibition as an effective strategy for reducing the leukemogenicity of t(8;21) AML.

Analysis of individual differences in radiosensitivity using genome editing

Current standards for radiological protection of the public have been uniformly established. However, individual differences in radiosensitivity are suggested to exist in human populations, which could be caused by nucleotide variants of DNA repair genes. In order to verify if such genetic variants are responsible for individual differences in radiosensitivity, they could be introduced into cultured human cells for evaluation. This strategy would make it possible to analyse the effect of candidate nucleotide variants on individual radiosensitivity, independent of the diverse genetic background. However, efficient gene targeting in cultured human cells is difficult due to the low frequency of homologous recombination (HR) repair. The development of artificial nucleases has enabled efficient HR-mediated genome editing to be performed in cultured human cells. A novel genome editing strategy, 'transcription activator-like effector nuclease (TALEN)-mediated two-step single base pair editing', has been developed, and this was used to introduce a nucleotide variant associated with a chromosomal instability syndrome bi-allelically into cultured human cells to demonstrate that it is the causative mutation. It is proposed that this editing technique will be useful to investigate individual radiosensitivity.

Effect of (6R)- and (6S)-tetrahydrobiopterin on L-3,4-dihydroxyphenylalanine (DOPA) formation in NRK fibroblasts transfected with human tyrosine hydroxylase type 2 cDNA

l-erythro-5,6,7,8-Tetrahydrobiopterin (BH(4)), which is the cofactor of aromatic amino acid hydroxylases, plays an important role in the biosyntheses of monoamine neurotransmitters. BH(4) exists as natural (6R)- and unnatural (6S)-isomers. In our previous reports, only (6R)-isomer significantly stimulated cofactor activity for tyrosine, tryptophan and phenylalanine hydroxylases (TH, TPH, PAH) in whole animals or in tissue slices. In this study we have compared the in situ cofactor activity on TH between natural (6R)- and unnatural (6S)-isomers in clonal cells. We have transfected human TH type 2 cDNA into the normal rat kidney (NRK) fibroblasts. These cells expressed TH protein, but had neither DOPA decarboxylase (DDC) nor BH(4). Thus, TH activity was observed only in the presence of exogenous BH(4). We compared the difference in in situ DOPA formation by TH activity in the presence of (6R)- or (6S)-BH(4) in the human TH-transfected cells. The effect of exogenous BH(4) was also compared between (6R)- and (6S)-isomers in rat pheochromocytoma PC12h cells, which contained approximately 100 ?M endogenous (6R)-BH(4). The rate of uptake of both BH(4) isomers into these cells increased in proportion to the pterin cofactor concentrations in the incubation medium up to 400 ?M but was nearly saturated at 1 mM BH(4). TH-transfected NRK fibroblasts formed DOPA only in the presence of exogenously added (6R)- or (6S)-BH(4) dose-dependently and released DOPA into the medium. At a saturating concentration of 1 mM, (6R)-BH(4) was approximately three times as active as (6S)-BH(4). In contrast, in PC12h cells which contained endogenous (6R)-BH(4) (approximately 100 ?M), exogenous (6R)-BH(4) activated DOPA formation maximally at 500 ?M about 10-fold, while (6S)-BH(4) activated it only slightly, about 2.5-fold. These results suggest that (6S)-isomer has lower cofactor activity with TH in the cells than (6R)-isomer. This TH transfected fibroblasts should be useful to assess cofactor activities of tetrahydropteridines in the cell.

Histopathological safety evaluation of newly-developed MgO sealer

We aimed to evaluate the subcutaneous tissue reaction to a newly-developed MgO Sealer for root canals. We injected the experimental material and three existing control materials into the dorsal area of 43 male ddY mice. One week and 12 weeks after embedding, the tissue surrounding the embedding sites was removed and histopathological examination was performed. The results demonstrate that the basic histopathological reaction is the formation of fibrous capsules consisting of granulation tissue around the experimental and control embedded materials. Based on our results, we believe that the newly-developed MgO Sealer is as safe as the existing control materials and can be considered for dental use as a root canal sealer.

Comparative examination of subcutaneous tissue reaction to high molecular materials in medical use

Polypropylene (PP), Polyethylene (PE) and polytetrafluoroethylene (FE) are high molecular materials in medical use. They are also used as the negative control materials for ISO 10993-6 international standard biological evaluation of medical devices. We examined tissue reactions to these materials embedded subcutaneously in the dorsal area of male ddY mice. One week and 12 weeks after embedding, the tissue surrounding the embedding site was removed and then histopathological examination was performed. Our results demonstrate that the basic histopathological reaction is the formation of fibrous capsule consisting of granulation tissue around the embedded materials. Based on our results, we believe that the high molecular materials such as, PP, PE and FE, can be considered for medical use as a biomaterials within the body.

Histopathological examination of newly-developed adhesive silicone denture relining material

We aimed to evaluate the subcutaneous tissue reaction to a newly developed adhesive silicone denture relining material, SG, (Neo Dental Chemical Products Co., Ltd. Tokyo, Japan). We embedded the experimental material SG and another existing control material, Roeko Seal (RS), in the dorsal area of 22 male ddY mice. One week and 12 weeks after the embedding, the tissues surrounding the embedded materials were removed and a histopathological examination was performed. The results demonstrate that the basic histopathological aspects are the formation of granulation tissue and the change of the tissue to fibrous capsule over time. The results suggests that the newly-developed SG is safe as compared with the control RS, whose composition is similar.

PKCgamma in Vc and C1/C2 is involved in trigeminal neuropathic pain

The aim of the present study was to clarify the involvement of protein kinase Cγ (PKCγ) in the facial neuropathic pain following infraorbital nerve injury. We analyzed the change in PKCγ expression in the trigeminal spinal subnucleus caudalis (Vc) and upper cervical spinal cord (C1/C2) following chronic constriction injury of the infraorbital nerve (ION-CCI). We also studied ION-CCI-mediated mechanical nocifensive behavior in rats. The mechanical head-withdrawal threshold significantly decreased 1 to 14 days after ION-CCI compared with that before ION-CCI and in sham rats. The expression of PKCγ was significantly larger in the ipsilateral Vc compared with the contralateral side in ION-CCI rats 3, 7, and 14 days after ION-CCI. Intrathecal (i.t.) administration of the PKCγ inhibitor chelerythrine prevented an increase in the PKCγ expression in the ipsilateral Vc. Moreover, i.t. administration of chelerythrine annulled ION-CCI-mediated reduction in the head-withdrawal threshold. Taken together, these findings suggest that PKCγ expression in the Vc played an important role in the mechanism of orofacial static mechanical allodynia following trigeminal nerve injury.

BubR1 localizes to centrosomes and suppresses centrosome amplification via regulating Plk1 activity in interphase cells

BubR1 is a critical component of the mitotic checkpoint that delays the onset of anaphase until all chromosomes have established bipolar attachment to the microtubules. We previously reported that mutations of the BUB1B gene (encoding BubR1) caused premature chromatid separation (PCS) syndrome, a condition characterized by constitutional aneuploidy and a high risk of childhood cancer. We here report that the cells from PCS syndrome patients have loss of regulation of the centrosome duplication machinery, resulting in centrosome amplification and multipolar mitosis. PCS syndrome cells show increased activity of Polo-like kinase 1 (Plk1), whose knockdown suppresses centrosome amplification. BubR1 localizes to centrosomes, physically interacts with Plk1 and inhibits Plk1 phosphorylation and its kinase activity during interphase. These results unravel a crucial role of BubR1 in preventing centrosome reduplication through negative regulation of Plk1 in interphase cells.

[Tracheostenosis caused by blunt thoracic trauma]

Blunt thoracic trauma rarely implicate retropharyngeal hematoma obstructing trachea. 85-year-old woman being struck on her cheek and anterior chest, visited our emergency room. She was nearly suffocated following stridor and dyspnea. Tracheal intubation relieved her dyspnea Chest computed tomography (CT) showed retropharyngeal hematoma obstructing trachea. 5 days conservative management reduced the hematoma and tracheal tube was extubated through an uneventful course.

NBS1 prevents chromatid-type aberrations through ATM-dependent interactions with SMC1

Nijmegen breakage syndrome shares several common cellular features with ataxia telangiectasia, including chromosomal instability and aberrant S- and G2-phase checkpoint regulation. We show here that after irradiation, NBS1 interacts physically with both BRCA1 and SMC1, a component of the cohesin complex, and that their interactions are completely abolished in AT cells. It is noted that BRCA1 is required for the interaction of NBS1 with SMC1, whereas the reverse is not the case, since BRCA1 is able to bind to NBS1 in the absence of an NBS1/SMC1 interaction as observed in MRE11- or RAD50-deficient cells. This indicates that ATM and BRCA1 are upstream of the NBS1/SMC1 interaction. Furthermore, the interaction of NBS1 with SMC1 requires both conserved domains of NBS in the N-terminus and the C-terminus, since they are indispensable for binding of NBS1 to BRCA1 and to MRE11/ATM, respectively. The interaction of NBS1 with SMC1 and the resulting phosphorylation are compromised in the clones lacking either the N- or C-terminus of NBS1, and as a consequence, chromatid-type aberrations are enhanced after irradiation. Our results reveal that ATM plays a fundamental role in promoting the radiation-induced interaction of NBS1 with SMC1 in the presence of BRCA1, leading to the maintenance of chromosomal integrity.

Centrosome amplification induced by survivin suppression enhances both chromosome instability and radiosensitivity in glioma cells

Glioblastoma is characterised by invasive growth and a high degree of radioresistance. Survivin, a regulator of chromosome segregation, is highly expressed and known to induce radioresistance in human gliomas. In this study, we examined the effect of survivin suppression on radiosensitivity in malignant glioma cells, while focusing on centrosome aberration and chromosome instability (CIN). We suppressed survivin by small interfering RNA transfection, and examined the radiosensitivity using a clonogenic assay and a trypan blue exclusion assay in U251MG (p53 mutant) and D54MG (p53 wild type) cells. To assess the CIN status, we determined the number of centrosomes using an immunofluorescence analysis, and the centromeric copy number by fluorescence in situ hybridisation. As a result, the radiosensitisation differed regarding the p53 status as U251MG cells quickly developed extreme centrosome amplification (=CIN) and enhanced the radiosensitivity, while centrosome amplification and radiosensitivity increased more gradually in D54MG cells. TUNEL assay showed that survivin inhibition did not lead to apoptosis after irradiation. This cell death was accompanied by an increased degree of aneuploidy, suggesting mitotic cell death. Therefore, survivin inhibition may be an attractive therapeutic target to overcome the radioresistance while, in addition, proper attention to CIN (centrosome number) is considered important for improving radiosensitivity in human glioma.

Temporary accumulation of glycogen in the epithelial cells of the developing mouse submandibular gland

Temporary accumulation of glycogen in the epithelial cells of the developing mouse submandibular gland was examined under light microscopic histochemistry and electron microscopy. To avoid loss of water-soluble glycogen during histological tissue preparation, fixation with ethanol and embedding in hydrophilic glycol methacrylate resin was used for light microscopy, and high-pressure freezing/freeze substitution for electron microscopy. Glycogen was detected on periodic acid-Schiff stain, periodic acid-thiosemicarbazide-silver proteinate reaction, and the digestion test with alpha-amylase. On embryonic day 14, glycogen began to accumulate in the proximal portions of the developing epithelial cords. On embryonic day 17, marked glycogen particles were seen at the basal portion of the ductal epithelial cells and an abrupt increase of glycogen accumulation occurred in the secretory cells in the terminal bulbs. Ultrastructural observation indicated large clumps of glycogen particles localized in the basal portion of the terminal bulb cells. The initiation of glycogen accumulation preceded the formation of lumens in the ducts and terminal bulbs. Furthermore, proliferation analysis by bromodeoxyuridine labeling showed that this glycogen accumulation followed the cessation of the epithelial cell proliferation. Postnatally, glycogen accumulation in the terminal bulbs became gradually inconspicuous and completely disappeared by postnatal day 3, but that in the ducts was retained until around postnatal day 12. Temporary glycogen accumulation after the cell proliferation and before/during the lumen formation and secretory granule formation suggests significant involvement of the carbohydrate metabolism in the organogenesis of the submandibular gland.

First Report of Chrysanthemum stem necrosis virus on Chrysanthemums in Japan

The chrysanthemum (Dendranthema grandiflorum), whose planted area comprises more than 6,000 ha in Japan, is one of the most important ornamental cut flower crops. In August 2006, necrotic streaks on stems, chlorotic and necrotic spots and rings on leaves, and leaf distortions were observed on chrysanthemum cvs. Jimba and Seinotama, with a disease incidence of more than 70% (approximately 30,000 plants), which represents approximately 1,000 m² of greenhouses of one grower in Hiroshima Prefecture, western Japan. Symptoms were similar to those caused by Tomato spotted wilt virus (TSWV) (genus Tospovirus, family Bunyaviridae). Frankliniella occidentalis was the major thrips species observed on symptomatic plants, followed by F. intonsa. Tospovirus-like spherical particles that were 80 to 100 nm in diameter were found in the infected leaves. After mechanical inoculation, a single lesion isolate reproduced the original symptoms observed in nature on healthy chrysanthemum plants (cv. Jimba). As determined by mechanical inoculation, host range and symptomatology of the isolate were similar to those described previously for Chrysanthemum stem necrosis virus (CSNV), including necrotic spots on Petunia hybrida (1). The isolate caused stunting, severe necrotic lesions on stems, necrotic spots, rings, and vein necrosis on systemically infected leaves of Lycopersicon esculentum (cv. House-momotaro). This virus reacted strongly with CSNV antiserum (DSMZ, Braunschweig, Germany) by indirect dot immuno-binding assay, and cross-reacted weakly with a monoclonal antibody to N protein of TSWV (3) using double-antibody sandwich-ELISA. Reverse transcription (RT)-PCR was conducted to verify virus infection. No amplification was observed from extracts of symptomatic plants (n = 10) by multiplex RT-PCR using TSWV and Impatiens necrotic spot virus specific primer sets (4), indicating that the diseased chrysanthemums were not doubly infected with these viruses. However, a DNA fragment of approximately 450 bp was amplified in samples by RT-PCR using tospovirus universal primers, BR60/65 (2). The nucleotide sequence of the amplified fragment had 98.1% identity with the corresponding region of the CSNV nucleocapsid protein gene (GenBank Accession No. AF067068). The above results indicate that the virus associated with a stem necrosis disease of chrysanthemums in Hiroshima is an isolate of CSNV. To our knowledge, this is the first report of CSNV in Japan. References: (1) I. C. Bezerra et al. Phytopathology 89:823, 1999. (2) M. Eiras et al. Fitopatol. Bras. 26:170, 2001. (3) S. Tsuda et al. Ann. Phytopathol. Soc. Jpn. 60:216, 1994. (4) H. Uga and S. Tsuda. Phytopathology 95:166, 2005.

Homologous recombination repair is regulated by domains at the N- and C-terminus of NBS1 and is dissociated with ATM functions

The proteins responsible for radiation sensitive disorders, NBS1, kinase ataxia-telangiectasia-(A-T)-mutated (ATM) and MRE11, interact through the C-terminus of NBS1 in response to the generation of DNA double-strand breaks (DSBs) and are all implicated in checkpoint regulation and DSB repair, such as homologous recombination (HR). We measured the ability of several NBS1 mutant clones and A-T cells to regulate HR repair using the DR-GFP or SCneo systems. ATM deficiency did not reduce the HR repair frequency of an induced DSB, and it was confirmed by findings that HR frequencies are only slightly affected by deletion of ATM-binding site at the extreme C-terminus of NBS1. In contrast, The HR-regulating ability is dramatically reduced by deletion of the MRE11-binding domain at the C-terminus of NBS1 and markedly inhibited by mutations in the FHA/BRCT domains at the N-terminus. This impaired capability in HR is consistent with a failure to observe MRE11 foci formation. Furthermore, normal HR using sister chromatid was completely inhibited by the absence of FHA/BRCT domains. These results suggested that the N- and C-terminal domains of NBS1 are the major regulatory domains for HR pathways, very likely through the recruitment and retention of the MRE11 nuclease to DSB sites in an ATM-independent fashion.

Osteoblasts provide a suitable microenvironment for the action of receptor activator of nuclear factor-kappaB ligand

Deficiency of osteoprotegerin (OPG), a soluble decoy receptor for receptor activator of nuclear factor-kappaB ligand (RANKL), in mice induces osteoporosis caused by enhanced bone resorption. Serum concentrations of RANKL are extremely high in OPG-deficient (OPG(-/-)) mice, suggesting that circulating RANKL is involved in osteoclastogenesis. RANKL(-/-) mice exhibit osteopetrosis, with the absence of osteoclasts. We examined the requirements for osteoclastogenesis using OPG(-/-) mice, RANKL(-/-) mice, and a system involving bone morphogenetic protein 2 (BMP-2)-induced ectopic bone formation. When collagen disks containing BMP-2 (BMP-2-disks) or vehicle were implanted into OPG(-/-) mice, osteoclast-like cells (OCLs) and alkaline phosphatase-positive OCLs appeared in BMP-2-disks but not the control disks. F4/80-positive osteoclast precursors were similarly distributed in both BMP-2- and control disks. Cells expressing RANKL were detected in the BMP-2-disks, and the addition of OPG to the disk inhibited OCL formation. Muscle cells in culture differentiated into alkaline phosphatase-positive cells in the presence of BMP-2 and accordingly expressed RANKL mRNA in response to PTH. This suggests that RANKL expressed by osteoblasts is a requirement for osteoclastogenesis. We then examined how osteoblasts are involved in osteoclastogenesis other than RANKL expression, using RANKL(-/-) mice. BMP-2- and control disks were implanted into RANKL(-/-) mice, which were injected with RANKL for 7 d. Many OCLs were observed in the BMP-2-disks and bone tissues but not the control disks. These results suggest that osteoblasts also play important roles in osteoclastogenesis through offering the critical microenvironment for the action of RANKL.

Nijmegen breakage syndrome and functions of the responsible protein, NBS1

Nijmegen breakage syndrome (NBS) is a rare recessive genetic disorder, characterized by bird-like facial appearance, early growth retardation, congenital microcephaly, immunodeficiency and high frequency of malignancies. NBS belongs to the so-called chromosome instability syndromes; in fact, NBS cells display spontaneous chromosomal aberrations and are hypersensitive to DNA double-strand break-inducing agents, such as ionizing radiations. NBS1, the gene underlying the disease, is located on human chromosome 8q21. The disease appears to be prevalent in the Eastern and Central European population where more than 90% of patients are homozygous for the founder mutation 657del5 leading to a truncated variant of the protein. NBS1 forms a multimeric complex with MRE11/RAD50 nuclease at the C-terminus and retains or recruits them at the vicinity of sites of DNA damage by direct binding to histone H2AX, which is phosphorylated by PI3-kinase family, such as ATM, in response to DNA damage. Thereafter, the NBS1-complex proceeds to rejoin double-strand breaks predominantly by homologous recombination repair in vertebrates. NBS cells also show to be defective in the activation of intra-S phase checkpoint. We review here some cellular and molecular aspects of NBS, which might contribute to the clinical symptoms of the disease.

'Scirrhous' type hepatocellular carcinomas: a special reference to expression of cytokeratin 7 and hepatocyte paraffin 1

AIMS

'Scirrhous' hepatocellular carcinoma (scirrhous HCC) is extremely rare and its characteristics remain unclear. We investigated the clinicopathological and immunohistochemical features of scirrhous HCC, compared with those of ordinary hepatocellular carcinoma (ordinary HCC).

METHODS AND RESULTS

We compared the clinicopathological and immunohistochemical features of 20 resected cases of scirrhous HCC with those of 69 resected cases of ordinary HCC. Scirrhous HCC was characterized by its gross and histological findings, such as a higher proportion of contiguous multinodular type tumours, the absence of a complete fibrous capsule around the tumour, the absence of tumour necrosis and highly preserved portal tracts in the tumour. The immunohistochemical results revealed a significantly higher expression of cytokeratin 7 and a significantly lower expression of hepatocyte paraffin 1 in scirrhous HCC than in ordinary HCC (P<0.0001, respectively). There were no significant differences in proliferative activity and survival curves between the patients with scirrhous HCC and those with ordinary HCC.

CONCLUSION

Scirrhous HCC has several particular gross, histological and immunohistochemical features. In particular, we would like to emphasize the greater immunohistochemical expression of cytokeratin 7 and lower expression of hepatocyte paraffin 1 in scirrhous HCC than in ordinary HCC.

The influence of mycophenolate mofetil versus azathioprine and mycophenolic acid pharmacokinetics on the incidence of acute rejection and infectious complications after renal transplantation

PURPOSE

The present retrospective study investigated the influence of mycophenolate mofetil (MMF) instead of azathioprine (AZA) as part of tacrolimus-based immunosuppression. Mycophenolic acid (MPA) pharmacokinetic (PK) parameters were used for associations with the incidence of acute rejection (AR) episodes and infectious complications after renal transplantation.

METHODS

The 66 consecutive renal transplant recipients reported herein excluded ABO-incompatible transplants or cytomegalovirus (CMV)-seronegative recipients. The immunosuppressive regimen consisted of tacrolimus, steroids, and AZA 1-2 mg/kg/d in 22 patients (between February 1998 and December 2000) or MMF 2 g/d in 44 patients (since January 2001). CMV infection was defined as positive CMV-antigenemia. MPA PK was studied on day 28 after transplantation in 21 recipients.

RESULTS

AR occurred in 13.6% of patients in the MMF group compared with 18.2% in the AZA group. The viral infection (CMV, varicella zoster virus, adenovirus hemorrhagic cystitis, and malignancy related to Epstein-Barr [EB] virus) rate was 22.7% in the MMF group and 0% in the AZA group (P = .015). There were no bacterial or fungal infections observed in the 2 groups. MMF dose per body weight was significantly lower among patients with AR than those without AR (25.1 vs 35.6 mg/kg; P = .026). There were no differences in MPA PK parameters between patients with and without viral infections.

CONCLUSIONS

Patients treated with MMF required less treatment for AR, however, there were no significant differences. MMF dose per body weight may play an important role in the occurrence of AR. Although virus infections occurred in recipients treated with MMF, MPA PK did not influence the infectious complications after renal transplantation.

Incidence and Risk Factors of Clinical Characteristics, Tacrolimus Pharmacokinetics, and Related Genomic Polymorphisms for Posttransplant Diabetes Mellitus in the Early Stage of Renal Transplant Recipients

PURPOSE

Posttransplant diabetes mellitus (PTDM) is an important complication in a tacrolimus (TAC)-based immunosuppressive regimen. The present study investigated the incidence, clinical risk factors, TAC pharmacokinetics (PK), and genomic polymorphisms related to TAC-PK or diabetes mellitus (DM) under the TAC-based immunosuppressive protocol.

PATIENTS AND METHODS

Seventy-one nondiabetic renal allograft recipients transplanted from February 1998 to March 2004 were studied. Patients with over 6.5 mg/dL of hemoglobin A1c on sequential blood samples or requiring insulin or oral antidiabetic agents around 6 months after transplantation were diagnosed as having PTDM.

RESULTS

Six months after transplantation, 10 recipients (14.1%) developed PTDM. The positive risk factors were age (P = .003) and body mass index (P = .035). There were no significant differences in gender distribution, pretransplant dialysis period, dialysis modality, acute rejection rate, total steroid doses, TAC-PK, or its related genomic polymorphisms between the two groups. In the DM-related polymorphisms, the frequency of PTDM was significant higher in patients with the VDR TaqI tt or Tt genotype than in those with the TT genotype (P = .013). After a multivariate analysis, age over 50 years (P = .007, odds ratio 8.92) and the presence of VDR TaqI t allele (P = .043, odds ratio 6.71) were correlated with the development of PTDM.

CONCLUSION

The incidence of PTDM in our series was 14.1%. Age over 50 years was a risk factor. The presence of VDR TaqI t allele might be a risk for PTDM. An association between TAC-PK and development of PTDM was not observed.

Crystallization and preliminary X-ray diffraction analysis of two lysinal derivatives of Achromobacter protease I

Two crystal forms of lysinal derivatives of Achromobacter protease I have been obtained. The first, modified by benzyloxycarbonyl-Val-lysinal crystallizes in the monoclinic space group P2(1) with unit-cell dimensions of a = 39.6, b = 71.2, c = 45.6 A and beta = 98.4 degrees. The second, modified by benzyloxycarbonyl-Leu-Leu-lysinal crystallizes in the orthorhombic space group I222 (or I2(1)2(1)2(1)) with unit-cell dimensions of a = 98.7, b = 102.2 and c = 55.8 A. The space groups and the unit-cell dimensions of the present two lysinal derivatives are different to those of the protease and TLCK- modified one. The space group of the protease is P1 with cell dimensions a = 39.53, b = 40.34, c = 43.92 A, alpha = 114.81, beta = 113.75 and gamma = 74.00 degrees and that of the TLCK-modified one is also P1 with cell dimensions of a = 37.30, b = 42.74, c = 48.02 A, alpha = 120.10, beta = 112.81 and gamma = 68.54 degrees. Diffraction to 1.9 A resolution for the Val-lysinal modified crystal and to 2.2 A resolution for the Leu-Leu-lysinal modified crystal has been observed using a rotating-anode X-ray generator. Full structure determinations of these lysinal-modified protease crystals may lead to an understanding of the molecular basis of enzyme-substrate interactions in the catalytic process of this protease.

Serum sex steroid hormone levels and polymorphisms of CYP17 and SRD5A2: implication for prostate cancer risk

Polymorphism of the steroid hormone-related genes might affect life-long androgen exposure, thus altering a risk of prostate cancer incidence. To evaluate the effect of the polymorphisms of CYP17 and SRD5A2 on serum steroid hormone levels, the 164 male Japanese cohort were tested for serum hormone levels and the genotype of the polymorphisms of CYP17 (T-C base substitution in the promoter region) and SRD5A2 (V89L). The linear trends across the CYP17 genotypes in serum-free testosterone and androstenedione levels were found, suggesting the importance of the polymorphism of CYP17 in determining the circulating androgen levels.

Histopathological safety evaluation of polyethylene glycol applied subcutaneously in mice

Polyethylene glycol is used as a non-aqueous solvent for a variety of medical agents. We believe it could also be used as a base component in root canal filling material and aimed to test the histological safety of subcutaneously injected polyethylene glycol. We injected polyethylene glycol subcutaneously into the dorsal area of 30 6-week-old anaesthetized male ddY mice. An equal number of mice were injected with propylene glycol as controls. One week, 3 weeks and 9 weeks after injection, the tissue surrounding the injection site was removed from 10 mice in each group and examined. We found no histopathological changes, degeneration, necrosis, foreign body reactions or granulation tissue proliferation in either group. Some inflammatory cell infiltration was observed in both groups. Based on these results, we believe that polyethylene glycol could be used safely as a base component of biomaterials for internal medical use, such as in root canal filling material.

Gluteal muscular and sciatic nerve metastases in advanced urinary bladder carcinoma: case report

We present a case of gluteal muscular and sciatic nerve metastases from urinary bladder carcinoma. T2-weighted magnetic resonance images demonstrated diffuse swelling and an increase in the signal of the right gluteus maximus muscle without destruction of the original arrangement of muscular fibers. Further, remarkable thickening of the right sciatic nerve showing a relatively hypointense signal was detected. Postcontrast T1-weighted images showed strong enhancement of these structures. Fine-needle aspiration biopsy with ultrasonographic guidance confirmed metastatic carcinoma cells in the right gluteal muscle and the sciatic nerve. These radiologic findings may represent a rare pattern of metastasis from urinary bladder carcinoma.

p16 Gene transfer increases cell killing with abnormal nucleation after ionising radiation in glioma cells

It is well established that cells synchronised at the G1–S phase are highly radiosensitive. In this study, p16-null human glioma cell lines were induced into G1 cell cycle arrest by adenovirus-mediated p16 gene transfer, and examined for radiation-induced cell killing. Clonogenic analysis and trypan blue extraction test showed that the p16 gene transfer enhanced radiation-induced cell killing in p16-null glioma cell lines. TUNEL assays and pulse-field gel electrophoresis confirmed that the radiation-induced cell killing of p16-transfected cells could be caused by a nonapoptotic mechanism. Gimsa staining demonstrated that irradiation alone or Ax-mock infection plus irradiation results in a slight increase in the frequency of cells with abnormal nucleus, compared to unirradiated uninfected or Ax-mock infected cells. However, Ax-hp16 or Ax-hp21 infection alone modestly increased the frequency of cells with abnormal nucleus (especially bi- and multinucleation), and 4-Gy irradiation of Ax-hp16 or Ax-hp21 infected cells substantially enhanced this frequency. These results suggest that there exists some unknown interaction between radiation and p16 in cytoplasm/membranes, which decreases cytokinesis and promotes abnormal nucleation. Thus, p16 expression prevented radiation-induced apoptosis by promoting abnormal nucleation, thereby leading to another mode of cell death.

Osteoprotegerin regulates bone formation through a coupling mechanism with bone resorption

Deficiency of osteoprotegerin (OPG), a soluble decoy receptor for receptor activator of nuclear factor-kappaB ligand (RANKL), in mice induces osteoporosis caused by enhanced bone resorption, but also accelerates bone formation. We examined whether bone formation is coupled with bone resorption in OPG-deficient (OPG-/-) mice using risedronate, an inhibitor of bone resorption. Histomorphometric analysis showed that bone formation-related parameters (e.g. mineral apposition rate and osteoblast surface/bone surface) in OPG-/- mice sharply decreased with suppression of bone resorption by daily injection of risedronate for 30 d. OPG-/- mice exhibited high serum alkaline phosphatase activity and osteocalcin concentration, both of which were decreased to the levels in wild-type mice by the risedronate injection. Serum levels of RANKL were markedly elevated in OPG-/- mice, but were unaffected by risedronate. The ectopic bone formation induced by bone morphogenetic protein-2 implantation into OPG-/- mice was not accelerated even with a high turnover rate of bone, but attenuation of mineral density from the ectopic bone was more pronounced than that in wild-type mice. These results suggest that bone formation is coupled with bone resorption at local sites in OPG-/- mice, and that serum RANKL levels do not reflect this coupling.

Quantitation of bovine macrophage colony-stimulating factor in bovine serum by ELISA

We established an enzyme-linked immunosorbent assay (ELISA) system for the quantitation of bovine macrophage colony-stimulating factor (M-CSF) and used it to measure the serum M-CSF levels in bovine fetuses and calves. The average serum M-CSF level was 2.7+/-1.5 ng/ml in 39 calves under 100 days old, and 1.8+/-0.8 ng/ml in 15 cattle between 101 and 418 days old. Fetal sera samples (n = 6) prepared from cattle between 150 and 280 days of gestational age had a higher average level of M-CSF (8.8+/-1.4 ng/ml). Alteration in serum M-CSF levels in each individual calf was also measured. The serum levels of M-CSF in calves at 0-1 day after birth ranged from 0.52 to 7.3 ng/ml. During the period 113-125 days after birth, serum levels were around 1.4+/-0.39 ng/ml. Although serum M-CSF levels generally decreased as the age of calves advanced, differences among individuals, especially among newborn calves, were observed.

Fat detection in gallbladder carcinoma with extensive xanthogranulomatous change demonstrated by chemical shift MR imaging

We present a case of gallbladder carcinoma, in which fat was detected on dual-echo chemical shift magnetic resonance imaging (MRI). Histologic analysis showed poorly differentiated adenocarcinoma associated with massive xanthogranulomatous change. Sudan IV staining successfully confirmed the presence of fat within the interstitial histiocytes. Although rare, gallbladder carcinoma with xanthogranulomatous change should be included in the differential diagnosis of fatty tumor involving the region of the liver as observed on chemical shift MRI.