Transcriptional regulation of the HIV-1 inhibitory factor human mannose receptor 1 by the myeloid-specific transcription factor PU.1.

HIV-1 infection of human macrophages leads to the downmodulation of human mannose receptor 1 (hMRC1), a cell-surface glycoprotein that is involved in the host innate immune response. We previously reported that downmodulation of hMRC1 involves the transactivator of transcription (Tat)-dependent transcriptional silencing of the hMRC1 promoter. However, the inhibitory effect of Tat on hMRC1 transcription was indirect and involved inhibition of the transcriptional activator PU.1, which normally upregulates hMRC1 expression in macrophages and other myeloid cells. We cloned a 284-bp fragment of the hMRC1 promoter, and within it, we identified four PU.1 box elements. We assessed the relative contribution of each of the four PU.1 boxes to PU.1-dependent transcriptional regulation and, surprisingly, found that only one of the four PU.1 boxes [PU.1(b)] was critically required for PU.1-mediated upregulation of luciferase expression. Transfer of this PU.1 box to a heterologous promoter conferred PU.1 responsiveness to an otherwise PU.1 insensitive promoter. Electrophoretic mobility shift assays identified this PU.1 box as a direct binding site for PU.1 both in the context of the hMRC1 promoter and the heterologous promoter. Furthermore, mutational analysis of the PU.1 protein identified the C-terminal DNA-binding domain in PU.1 as the region responsible for interaction with the PU.1 box. Recombinant HIV-1 Tat protein did not bind to the hMRC1 promoter element but efficiently interfered with the binding of PU.1 protein to the hMRC1 promoter. Thus, Tat is likely to inhibit the formation of active PU.1 transcription complexes, presumably by binding to and depleting common transcriptional cofactors.IMPORTANCEHIV-1 infection of cells results in the modulation of cellular gene expression by virus-encoded proteins in a manner that benefits the virus. We reported that HIV-1 transactivator of transcription (Tat) dysregulates the expression of the human mannose receptor 1 (hMRC1). hMRC1 is involved in the innate immune response of macrophages to foreign pathogens. Tat does not act directly on the hMRC1 promoter but instead inhibits PU.1, a cellular transcription factor regulating hMRC1 gene expression. Here, we characterize the PU.1-dependent regulation of hMRC1 expression. We identified four potential PU.1 binding sites in the hMRC1 promoter region but found that only one, PU.1(b), functioned as a true binding site for PU.1. Transfer of the PU.1(b) box to a heterologous promoter did not activate this promoter per se but rendered it responsive to PU.1. Our results support the view that PU.1 acts as a transcriptional co-factor whose activity can be regulated by HIV-1 Tat.

The Myeloid-Specific Transcription Factor PU.1 Upregulates Mannose Receptor Expression but Represses Basal Activity of the HIV-LTR Promoter.

Human mannose receptor 1 (MRC1) is a cell surface receptor expressed in macrophages and other myeloid cells that inhibits human immunodeficiency virus type 1 (HIV-1) particle release by tethering virions to producer cell membranes. HIV-1 counteracts MRC1 expression by inhibiting mrc1 transcription. Here, we investigated the mechanism of MRC1 downregulation in HIV-1-infected macrophages. We identified the myeloid cell-specific transcription factor PU.1 as critical for regulating MRC1 expression. In the course of our study, we recognized a complex interplay between HIV-1 Tat and PU.1 transcription factors: Tat upregulated HIV-1 gene expression but inhibited mrc1 transcription, whereas PU.1 inhibited HIV-1 transcription but activated MRC1 expression. Disturbing this equilibrium by silencing PU.1 resulted in increased HIV-1 gene expression and reduced MRC1 promoter activity. Our study identified PU.1 as a central player in transcriptional control, regulating a complex interplay between viral and host gene expression in HIV-infected macrophages. IMPORTANCE HIV-1 replication in primary human cells depends on the activity of virus-encoded proteins but also involves cellular factors that can either promote (viral dependency factors) or inhibit (host restriction factors) virus replication. In previous work, we identified human MRC1 as a macrophage-specific host restriction factor that inhibits the detachment of viral particles from infected cells. Here, we report that HIV-1 counteracts this effect of MRC1 by imposing a transcriptional block on cellular MRC1 gene expression. The transcriptional inhibition of the MRC1 gene is accomplished by Tat, an HIV-1 factor whose best-described function actually is the enhancement of HIV-1 gene expression. Thus, HIV-1 has evolved to use the same protein for (i) activation of its own gene expression while (ii) inhibiting expression of MRC1 and other host factors.

Expression of proinflammatory cytokines and proinsulin by bone marrow-derived cells for fracture healing in long-term diabetic mice.

BACKGROUND: Diabetes mellitus (DM) causes bone dysfunction due to poor bone quality, leading to severe deterioration in patient of quality of life. The mechanisms of bone metabolism in DM remain unclear, although chemical and/or mechanical factors are known to disrupt the homeostasis of osteoblasts and osteoclasts. The purpose of this study was to identify the changes of osteoblasts and osteoclasts under long-term hyperglycaemic conditions, using a mouse fracture model of long-term hyperglycemia (LT-HG). METHODS: C57BL/6J mice and green fluorescent protein (GFP) -positive bone marrow transplanted C57BL/6J mice with LT-HG, maintained under a state of hyperglycaemia for 2 months, were used in this study. After the experimental fracture, we examined the immunohistochemical expression of proinsulin and tumor necrosis factor (TNF) -α at the fracture site. C57BL/6J fracture model mice without hyperglycaemia were used as controls. RESULTS: In the LT-HG mice, chondrocyte resorption was delayed, and osteoblasts showed an irregular arrangement at the callus site. The osteoclasts were scattered with a decrement in the number of nuclei. The expression of proinsulin was confirmed in bone marrow derived cells (BMDCs) with neovascularization 2 and 3 weeks after fracture. Immunopositivity for TNF-α was also confirmed in immature chondrocytes and BMDCs with neovascularization at 2 weeks, and the number of positive cells was not decreased at 3 weeks. Examination of GFP-grafted hyperglycaemic mice showed that the majority of cells at the fracture site were GFP-positive. Immunohistochemistry showed that the rate of double positives was 15% for GFP and proinsulin and 47% for GFP and TNF-α. CONCLUSION: LT-HG induces an increase in the number of proinsulin and TNF-α positive cells derived from BMDCs. We suggest that proinsulin and TNF-α positive cells are involved in both bone formation and bone resorption after fracture under hyperglycaemic conditions, resulting in the delay of bone healing.

Phosphorylation of the HIV-1 capsid by MELK triggers uncoating to promote viral cDNA synthesis.

Regulation of capsid disassembly is crucial for efficient HIV-1 cDNA synthesis after entry, yet host factors involved in this process remain largely unknown. Here, we employ genetic screening of human T-cells to identify maternal embryonic leucine zipper kinase (MELK) as a host factor required for optimal uncoating of the HIV-1 core to promote viral cDNA synthesis. Depletion of MELK inhibited HIV-1 cDNA synthesis with a concomitant delay of capsid disassembly. MELK phosphorylated Ser-149 of the capsid in the multimerized HIV-1 core, and a mutant virus carrying a phosphorylation-mimetic amino-acid substitution of Ser-149 underwent premature capsid disassembly and earlier HIV-1 cDNA synthesis, and eventually failed to enter the nucleus. Moreover, a small-molecule MELK inhibitor reduced the efficiency of HIV-1 replication in peripheral blood mononuclear cells in a dose-dependent manner. These results reveal a previously unrecognized mechanism of HIV-1 capsid disassembly and implicate MELK as a potential target for anti-HIV therapy.

The Powdering Process with a Set of Ceramic Mills for Green Tea Promoted Catechin Extraction and the ROS Inhibition Effect.

For serving green tea, there are two prominent methods: steeping the leaf or the powdered leaf (matcha style) in hot water. The purpose of the present study was to reveal chemical and functional differences before and after the powdering process of green tea leaf, since powdered green tea may contribute to expanding the functionality because of the different ingesting style. In this study, we revealed that the powdering process with a ceramic mill and stirring in hot water increased the average extracted concentration of epigallocatechin gallate (EGCG) by more than three times compared with that in leaf tea using high-performance liquid chromatography (HPLC) and liquid chromatography-tandem mass Spectrometry (LC-MS/MS) analyses. Moreover, powdered green tea has a higher inhibition effect of reactive oxygen species (ROS) production in vitro compared with the same amount of leaf tea. Our data suggest that powdered green tea might have a different function from leaf tea due to the higher catechin contents and particles.

A carboxy-terminally truncated human CPSF6 lacking residues encoded by exon 6 inhibits HIV-1 cDNA synthesis and promotes capsid disassembly.

Since HIV-1 replication is modulated at multiple stages by host cell factors, identification and characterization of those host cell factors are expected to contribute to the development of novel anti-HIV therapeutics. Previous studies showed that a C-terminally truncated cytosolic form of cleavage and polyadenylation-specific factor 6 (CPSF6-358) inhibits HIV-1 infection through interference with HIV-1 trafficking to the nucleus. Here we identified and characterized a different configuration of C-terminally truncated human CPSF6 (hCPSF6-375) through cDNA expression cloning coupled with ganciclovir-mediated lethal selection. Notably, hCPSF6-375, but not mouse CPSF6-358 (mCPSF6-358) as previously reported, remarkably interfered with viral cDNA synthesis after HIV-1 infection. Moreover, we found that hCPSF6-375 aberrantly accelerated the disassembly of the viral capsid in target cells, while CPSF6-358 did not. Sequence comparison of CPSF6-375 and CPSF6-358 cDNAs showed a lack of exon 6 and additional coding sequence for 54 amino acid residues in the C terminus of hCPSF6-375. Mutational analyses revealed that the residues encoded by exon 6, but not the C-terminal 54 residues in hCPSF6-375, is responsible for impaired viral cDNA synthesis by hCPSF6-375. This is the first report demonstrating a novel mode of HIV-1 inhibition by truncated forms of CPSF6 that involves rapid capsid disassembly and inhibition of viral cDNA synthesis. These findings could facilitate an increased understanding of viral cDNA synthesis in light of the viral capsid disassembly.

Machine learning-based detection of sleep-disordered breathing in hypertrophic cardiomyopathy.

BACKGROUND: Hypertrophic cardiomyopathy (HCM) is often concomitant with sleep-disordered breathing (SDB), which can cause adverse cardiovascular events. Although an appropriate approach to SDB prevents cardiac remodelling, detection of concomitant SDB in patients with HCM remains suboptimal. Thus, we aimed to develop a machine learning-based discriminant model for SDB in HCM. METHODS: In the present multicentre study, we consecutively registered patients with HCM and performed nocturnal oximetry. The outcome was a high Oxygen Desaturation Index (ODI), defined as 3% ODI >10, which significantly correlated with the presence of moderate or severe SDB. We randomly divided the whole participants into a training set (80%) and a test set (20%). With data from the training set, we developed a random forest discriminant model for high ODI based on clinical parameters. We tested the ability of the discriminant model on the test set and compared it with a previous logistic regression model for distinguishing SDB in patients with HCM. RESULTS: Among 369 patients with HCM, 228 (61.8%) had high ODI. In the test set, the area under the receiver operating characteristic curve of the discriminant model was 0.86 (95% CI 0.77 to 0.94). The sensitivity was 0.91 (95% CI 0.79 to 0.98) and specificity was 0.68 (95% CI 0.48 to 0.84). When the test set was divided into low-probability and high-probability groups, the high-probability group had a higher prevalence of high ODI than the low-probability group (82.4% vs 17.4%, OR 20.9 (95% CI 5.3 to 105.8), Fisher's exact test p<0.001). The discriminant model significantly outperformed the previous logistic regression model (DeLong test p=0.03). CONCLUSIONS: Our study serves as the first to develop a machine learning-based discriminant model for the concomitance of SDB in patients with HCM. The discriminant model may facilitate cost-effective screening tests and treatments for SDB in the population with HCM.

Asialoerythropoietin exerts stronger angiogenic activity than erythropoietin via its binding affinity to tissue.

PURPOSE: Although erythropoietin (EPO) is known to express angiogenic and cardioprotective effects, it also induces hypertension, polycythemia, and platelet activation, which may cause serious adverse effects in patients with cardiovascular diseases. We compared the angiogenic effects of EPO and its nonerythropoietic derivative, asialo-EPO (AEPO). METHODS: Lower limb ischemia was induced in ICR and C57/BL mice. Mice were injected intramuscularly with 2 µg/kg of EPO derivatives for 6 or 7 days. To assess biological differences, the tissue affinity of both EPO derivatives was analyzed in vitro using heparin affinity column chromatography. Tissue affinity was also analyzed in vivo using an intramuscular pharmacokinetic study. RESULTS: The survival of ischemic legs was better in the AEPO group than that in the EPO group (5/13 = 38.5 % vs 1/13 = 7.7 %, p < 0.05), and an increase in regenerated vessels was observed in the AEPO group, but not in the EPO group in ICR mice. Vessel/muscle ratios in control, EPO, and AEPO groups were 0.50 ± 0.34, 0.61 ± 0.32, and 2.83 ± 1.13, respectively (p < 0.0001). On the other hand, regenerated vessels were observed in both EPO and AEPO groups (p < 0.001) in C57/BL mice. AEPO, but not EPO, expressed heparin affinity in vitro. Intramuscularly injected EPO gradually decreased in muscle tissue, while AEPO was maintained at 2.5 ng/muscle for 1 day after several hours of a rapid clearance phase in vivo. CONCLUSIONS: AEPO exerts stronger angiogenic effects than those of EPO presumably via its tissue affinity. Administration of AEPO is a promising option for the treatment of patients with critical limb ischemia.

Human Mannose Receptor 1 Attenuates HIV-1 Infectivity in a Virus Isolate-Specific Manner.

Human mannose receptor 1 (hMRC1) is a transmembrane glycoprotein that belongs to the C-type lectin family and is expressed on the surface of most tissue macrophages. hMRC1 contributes to the binding and transmission of HIV-1 and is involved in the endocytic uptake of HIV-1 for subsequent antigen presentation. We previously reported that hMRC1 functions as an antiviral factor by inhibiting virus release through a BST-2-like mechanism. The inhibition of virus release was not virus isolate-specific and, surprisingly, was not Env-dependent. We now report on another hMRC1 antiviral function that affects the infectivity of viral particles. Unlike its effect on virus release, the inhibition of viral infectivity by hMRC1 was virus isolate-specific. An analysis of chimeric Env revealed that the Env V3 region was a critical determinant for the inhibitory effect of hMRC1. Of note, exogenously expressed hMRC1 was packaged into viral particles in an Env-independent manner. Co-immunoprecipitation studies revealed a strong interaction of the hMRC1-sensitive NL43 Env with hMRC1, while the hMRC1-insensitive Envs of AD8 and 49.5 isolates interacted poorly if at all with hMRC1. An analysis of a panel of Transmitted/Founder (T/F) viruses revealed that all of them were R5-tropic, and more than half of them were inhibited by hMRC1. The detailed mechanism of how hMRC1 inhibits viral infectivity remains to be investigated. However, the high-affinity binding of hMRC1 to Env may cause a conformational change around the Env V3 region or obstruct the Env V3 region and may make it inaccessible for subsequent interaction with the coreceptor during virus entry.

Increased Cellular Expression of Interleukin-6 in Patients With Ossification of the Posterior Longitudinal Ligament.

STUDY DESIGN: We performed histologic, immunohistochemical, immunoblot examination and suspension array analyses of cytokine expression in cultured cells derived from human cervical ossification of the posterior longitudinal ligament (OPLL). OBJECTIVE: To determine the roles of interleukin-6 (IL-6) during the maturation of osteoblasts and chondrocytes associated with the development of OPLL. SUMMARY OF BACKGROUND DATA: Ectopic OPLL affects ~3% of the general population, with a higher incidence in Asian ethnic groups. Alterations in cytokine profiles may influence osteoblast differentiation, but the mechanisms and signaling pathways associated with the ossification process remain unclear. METHODS: Samples were collected from 14 patients with OPLL who had undergone spinal surgery and seven with cervical spondylotic myelopathy without OPLL. Tissue sections were used for histologic and immunohistochemical studies, and primary cells from ligamentum samples were used for cytokine array and immunoblotting. A suspension array was used to measure the concentrations of 27 inflammatory cytokines or growth factors. RESULTS: Suspension array and immunoblot analyses revealed significantly elevated levels of IL-6 in OPLL patients. Alterations in IL-6 concentrations were found to alter the expression of the genes Sox9 , Runx2 , and SIRT1 . In addition, immunohistochemical analysis revealed that these factors are present in mesenchymal cells within the degenerative portion of the ligament matrix that is adjacent to the ossification front. CONCLUSIONS: IL-6 plays a profound role in the osteoblast differentiation process along with the induction of chondrocyte hypertrophy and cell apoptosis in the early stages of ossification in OPLL. These changes in cytokine profiles are essential factors for regulation of the ectopic ossified plaque in OPLL.

HIV-1 Vpr Induces Degradation of Gelsolin, a Myeloid Cell-Specific Host Factor That Reduces Viral Infectivity by Inhibiting the Expression and Packaging of the HIV-1 Env Glycoprotein.

Gelsolin (GSN) is a structural actin-binding protein that is known to affect actin dynamics in the cell. Using mass spectrometry, we identified GSN as a novel Vpr-interacting protein. Endogenous GSN protein was expressed at detectable levels in monocyte-derived macrophages (MDM) and in THP-1 cells, but it was undetectable at the protein level in other cell lines tested. The HIV-1 infection of MDM was associated with a reduction in GSN steady-state levels, presumably due to the Vpr-induced degradation of GSN. Indeed, the coexpression of GSN and Viral protein R (Vpr) in transiently transfected HEK293T cells resulted in the Vpr-dependent proteasomal degradation of GSN. This effect was observed for Vprs from multiple virus isolates. The overexpression of GSN in HEK293T cells had no effect on Gag expression or particle release, but it reduced the expression and packaging of the HIV-1 envelope (Env) glycoprotein and reduced viral infectivity. An analysis of the HIV-1 splicing patterns did not reveal any GSN-dependent differences, suggesting that the effect of GSN on Env expression was regulated at a posttranscriptional level. Indeed, the treatment of transfected cells with lysosomal inhibitors reversed the effect of GSN on Env stability, suggesting that GSN reduced Env expression via enhanced lysosomal degradation. Our data identify GSN as a macrophage-specific host antiviral factor that reduces the expression of HIV-1 Env. IMPORTANCE Despite dramatic progress in drug therapies, HIV-1 infection remains an incurable disease that affects millions of people worldwide. The virus establishes long-lasting reservoirs that are resistant to currently available drug treatments and allow the virus to rebound whenever drug therapy is interrupted. Macrophages are long-lived cells that are relatively insensitive to HIV-1-induced cytopathicity and thus could contribute to the viral reservoir. Here, we identified a novel host factor, gelsolin, that is expressed at high levels in macrophages and inhibits viral infectivity by modulating the expression of the HIV-1 Env glycoprotein, which is critical in the spread of an HIV-1 infection. Importantly, the viral protein Vpr induces the degradation of gelsolin and thus counteracts its antiviral activity. Our study provides significant and novel insights into HIV-1 virus-host interactions and furthers our understanding of the importance of Vpr in HIV-1 infection and pathogenesis.

Onset of Chronic Expanding Hematoma 25 Years After Total Hip Arthroplasty.

Chronic expanding hematoma (CEH) is a rare anatomical condition that gradually expands due to trauma or surgery. We report the case of a 56-year-old woman who developed CEH 25 years after metal-on-polyethylene total hip arthroplasty. She presented with swelling and radiating pain in the right inguinal region. Tocilizumab was administered for treating rheumatoid arthritis and renal amyloid A amyloidosis. Diagnostic imaging and partial resection revealed a soft tissue mass and a CEH, respectively. The symptoms recurred 6 months later; dialysis was initiated, and the CEH was resected under general anesthesia, leading to improvement. This case report emphasizes the importance of prompt diagnosis and intervention in CEH management for preventing further complications and improving the patient's quality of life.

Erythropoietin, but not asialoerythropoietin or carbamyl-erythropoietin, attenuates monocrotaline-induced pulmonary hypertension in rats.

Erythropoietin (EPO) has long been utilized for the treatment of renal anemia. The erythropoietin receptor (EPOR) is also expressed in the cardiovascular and central nervous systems in addition to an erythroid lineage, to provide an organoprotective role against several types of cellular stress. Pulmonary hypertension (PH) is a poor prognostic disease caused by primary and secondary pulmonary vascular injury. We observed the effects of EPO derivatives on monocrotaline-induced PH in rats on the supposition that EPO may protect small arteries from injury. Asialoerythropoietin (AEPO) lacks sialic acids in the termini of carbohydrate chains that results in rapid clearance from blood. Carbamyl-erythropoietin (CEPO) interacts with EPOR/ßc heterodimers, but not with EPOR homodimers expressed in erythroid cells. Monocrotaline-injected rats were treated with continuous intravenous injection of 2500 ng/kg/day of EPO, AEPO, or CEPO for 21 days, and lung histology, cardiac function, and mRNA expression in the lungs were examined. Wall thickening of small arteries in the lungs and PH were improved by administration of EPO, but not by its non-hematopoietic derivatives, AEPO, or CEPO. Erythropoietin administration increased mRNA expression of the anti-apoptotic molecule, Bcl-xL, and maintained expression of the CD31 antigen. We conclude that lungs may express EPOR homoreceptors, but not heteroreceptors. Adequate serum erythropoietin levels may be essential for pulmonary protective effects.

Novel electron microscopic staining method using traditional dye, hematoxylin.

Uranyl acetate (UA) has been routinely used as a staining solution for ultrathin sections used in biological electron microscopy. As a radioactive nuclear material, UA is subject to strict international regulations. To develop an alternative and easy-to-use staining method for ultrathin sections, we examined various commercial light microscopic dyes. We found that Mayer's hematoxylin followed by Reynold's lead citrate solution showed staining results comparable to UA and Reynold's lead citrate solution, and this method is therefore suggested as a reliable and promising alternative to UA staining.

Cytokine Profile From the Ligamentum Flavum in Patients with Ossification of the Posterior Longitudinal Ligament in the Cervical Spine.

STUDY DESIGN: Histological, immunohistochemical, and suspension array analyses of cytokine expression in human cervical ossification of the posterior longitudinal ligament (OPLL). OBJECTIVES: The aim of this study was to determine whether changes in the cytokine profile reflect the maturation of chondrocytes and osteoblasts are associated with OPLL development. SUMMARY OF BACKGROUND DATA: OPLL progresses gradually over a prolonged period and may lead to serious spinal cord complications. However, treatment methods only include conservative therapy for neurological symptoms or surgical decompression, whereas preventive therapy for OPLL remains nonexistent. METHODS: Ligamentous samples were harvested from 24 patients with OPLL who underwent spinal surgery, and five control samples from cervical spondylotic myelo/radiculopathy patients without OPLL. Tissue sections were used for immunohistochemical studies and primary cells were cultured from the ligamentous samples for cytokine profiling. Using a suspension array system, concentrations of 27 inflammatory cytokines or growth factors were measured to generate the cytokine profiles. RESULTS: Suspension array and immunoblot analysis revealed significant increments in the levels of interleukin (IL)-6, IL-1α, basic fibroblast growth factor, and RANTES in patients with OPLL. Immunohistochemical analysis further revealed that these factors were present in mesenchymal cells within the degenerative portion of the ligamentous matrix. CONCLUSION: Our findings suggest that specific changes in the cytokine profile during ossification promote osteoblast differentiation, thereby providing new insights into OPLL pathogenesis. Moreover, this work supports the development of a new therapeutic method for preventing OPLL progression by regulating the cytokine profiles.Level of Evidence: 3.

Incidence of Cranial Adjacent Segment Disease after Posterior Lumbar Interbody Fusion Using the Cortical Bone Trajectory Technique for the Treatment of Single-Level Degenerative Lumbar Spondylolisthesis; More than a 2-Year Follow-Up.

INTRODUCTION: Posterior lumbar interbody fusion (PLIF) is a widely used effective, safe, and established treatment for degenerative spinal disorders. Adjacent segment disease (ASD) is one of the serious concerns governing the clinical results following spinal fusion surgery. Cortical bone trajectory (CBT) is an alternative and less-invasive technique for lumbar pedicle screw placement. Its unique medial and caudal entry point has the potential to prevent an iatrogenic facet joint violence leading to the ASD; however, the incidence of ASD following PLIF using the CBT technique (CBT-PLIF) remains unknown. METHODS: Among patients surgically treated with CBT-PLIF in our institute, 52 consecutive patients (13 males, 39 females) with single-level degenerative lumbar spondylolisthesis (DLS) who were followed up for at least 24 months were exclusively enrolled. Their clinical and radiological features, including the incidence of radiographical and symptomatic ASD and significantly associated factor for the developing radiographical ASD, were retrospectively measured. RESULTS: In the present study, we could confirm significant neurological improvement and reduction of the spondylolisthesis with mean follow-up period of 43 months. Radiographical and symptomatic ASD was observed in 14 (27%) and 2 (3.8%) cases, respectively. We compared these two groups and found that the latest lumbar lordosis was significantly different between the two groups, but not in age, body mass index, and Japan Orthopaedic Association score. Two patients with symptomatic ASD required additional surgical treatment around 1 year following the initial surgery. CONCLUSIONS: The present study, even though it is preliminary, revealed that CBT-PLIF can achieve a neurological improvement and an effective reduction of spondylolisthesis for the treatment of single-level DLS. The CBT technique is capable of reducing the incidence of ASD compared with the traditional technique; however, we must keep in mind that appropriate postoperative lumbar lordosis should be achieved. Larger, longer-term follow-up studies are required to elucidate the clinical output of CBT-PLIF.

Gelatin Sponge as an Anchorage for Three-dimensional Culture of Colorectal Cancer Cells.

BACKGROUND: Compared to two-dimensional cultures, three-dimensional (3D) cultures have many advantages in cancer studies. Nevertheless, their implementation is unsatisfactory. This study aimed to develop an anchorage-dependent 3D culture model for colorectal cancer research. MATERIALS AND METHODS: Human HCT116, DLD-1 and SW620 colorectal cell lines were cultured in a gelatin sponge, and its applicability for morphological examination was studied. RESULTS: The resulting specimens were suitable for scanning electron microscopy, transmission electron microscopy, and immunohistochemical examination. HCT116 formed smaller structures and migrated through the pores of the sponge. DLD-1 formed larger structures with tight cell-to-cell adhesion. SW620 also formed large structures but small clustered cells tended to attach to the anchorage more favorably. Immunohistochemical staining demonstrated phosphorylated yes-associated protein (YAP) localized near the attachment site in HCT116 cells. CONCLUSION: Because the gelatin sponge provided suitable anchorage and the cultured cells formed distinguishable 3D structures, this method may be useful for further colorectal cancer research.

[A computerized method for detection of acute cerebral infarction on CT images].

This paper proposes a computerized method for automated detection of acute cerebral infarction (ACI) on CT images. This method is based on the difference value of image features in the two regions-of-interests (ROIs) selected at symmetrical positions. In our computerized method, first, we segmented the brain parenchyma by the thresholding technique after correction of inclination of the midsagittal plane with translation and rotation of the image. Then we selected the middle cerebral artery (MCA) region of the brain parenchyma. Moreover, many ROIs with a 32×32 matrix size were selected in the MCA region. In addition, image features in each ROI were determined from the statistical analysis, the co-occurrence matrix and the run length matrix. Finally, ROIs with ACI were classified by using a linear discriminant analysis with difference values of image features in two ROIs at symmetrical positions. Nineteen cases with ACI and normal 14 cases were employed in this study. As a result of our experiments, the sensitivity of detection of ACI was 88.0% with an average number of false positives of 4.6 per case. Our computerized method provided a relatively high performance for detection of ACI. Therefore, we believe this method would be useful for an algorithm of a computer-aided diagnosis to detect ACI on CT images.

eIF4A2 is a host factor required for efficient HIV-1 replication.

Host factors are required for efficient HIV-1 replication. To identify these factors, genome-wide RNA interference screening was performed using a human T cell line. In the present study, we assessed whether eukaryotic translation initiation factor 4A isoform 2 (eIF4A2), a DEAD-box protein identified in our screen, is necessary for efficient HIV-1 replication. Exploiting MT4C5 cells depleted of eIF4A2 by stable expression of eIF4A2-specific short-hairpin RNA (shRNA) using a lentiviral system, we found that depletion of eIF4A2 markedly inhibited the infection of a replication-competent reporter HIV-1. eIF4A2 depletion reduced the efficiency of viral cDNA synthesis with virion entry into target cells being unaffected. Depletion of eIF4A2 also inhibited HIV-1 spreading infection in a knockdown level-dependent manner. These results suggest that HIV-1 requires eIF4A2 for optimal replication in human T cells.

N-terminally truncated POM121C inhibits HIV-1 replication.

Recent studies have identified host cell factors that regulate early stages of HIV-1 infection including viral cDNA synthesis and orientation of the HIV-1 capsid (CA) core toward the nuclear envelope, but it remains unclear how viral DNA is imported through the nuclear pore and guided to the host chromosomal DNA. Here, we demonstrate that N-terminally truncated POM121C, a component of the nuclear pore complex, blocks HIV-1 infection. This truncated protein is predominantly localized in the cytoplasm, does not bind to CA, does not affect viral cDNA synthesis, reduces the formation of 2-LTR and diminished the amount of integrated proviral DNA. Studies with an HIV-1-murine leukemia virus (MLV) chimeric virus carrying the MLV-derived Gag revealed that Gag is a determinant of this inhibition. Intriguingly, mutational studies have revealed that the blockade by N-terminally-truncated POM121C is closely linked to its binding to importin-ß/karyopherin subunit beta 1 (KPNB1). These results indicate that N-terminally-truncated POM121C inhibits HIV-1 infection after completion of reverse transcription and before integration, and suggest an important role for KPNB1 in HIV-1 replication.