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1.
J Virol ; 97(8): e0074923, 2023 08 31.
Article in English | MEDLINE | ID: mdl-37504572

ABSTRACT

Interferon-induced protein with tetratricopeptide repeats 2, Ifit2, is critical in restricting neurotropic murine-ß-coronavirus, RSA59 infection. RSA59 intracranial injection of Ifit2-deficient (-/-) compared to wild-type (WT) mice results in impaired acute microglial activation, reduced CX3CR1 expression, limited migration of peripheral lymphocytes into the brain, and impaired virus control followed by severe morbidity and mortality. While the protective role of Ifit2 is established for acute viral encephalitis, less is known about its influence during the chronic demyelinating phase of RSA59 infection. To understand this, RSA59 infected Ifit2-/- and Ifit2+/+ (WT) were observed for neuropathological outcomes at day 5 (acute phase) and 30 post-infection (chronic phase). Our study demonstrates that Ifit2 deficiency causes extensive RSA59 spread throughout the spinal cord gray and white matter, associated with impaired CD4+ T and CD8+ T cell infiltration. Further, the cervical lymph nodes of RSA59 infected Ifit2-/- mice showed reduced activation of CD4+ T cells and impaired IFNγ expression during acute encephalomyelitis. Interestingly, BBB integrity was better preserved in Ifit2-/- mice, as evidenced by tight junction protein Claudin-5 and adapter protein ZO-1 expression surrounding the meninges and blood vessels and decreased Texas red dye uptake, which may be responsible for reduced leukocyte infiltration. In contrast to sparse myelin loss in WT mice, the chronic disease phase in Ifit2-/- mice was associated with severe demyelination and persistent viral load, even at low inoculation doses. Overall, our study highlights that Ifit2 provides antiviral functions by promoting acute neuroinflammation and thereby aiding virus control and limiting severe chronic demyelination. IMPORTANCE Interferons execute their function by inducing specific genes collectively termed as interferon-stimulated genes (ISGs), among which interferon-induced protein with tetratricopeptide repeats 2, Ifit2, is known for restricting neurotropic viral replication and spread. However, little is known about its role in viral spread to the spinal cord and its associated myelin pathology. Toward this, our study using a neurotropic murine ß-coronavirus and Ifit2-deficient mice demonstrates that Ifit2 deficiency causes extensive viral spread throughout the gray and white matter of the spinal cord accompanied by impaired microglial activation and T cell infiltration. Furthermore, infected Ifit2-deficient mice showed impaired activation of T cells in the cervical lymph node and relatively intact blood-brain barrier integrity. Overall, Ifit2 plays a crucial role in mounting host immunity against neurotropic murine coronavirus in the acute phase while preventing mice from developing viral-induced severe chronic neuroinflammatory demyelination, the characteristic feature of human neurological disease multiple sclerosis (MS).


Subject(s)
Coronavirus Infections , Multiple Sclerosis , Murine hepatitis virus , White Matter , Mice , Humans , Animals , White Matter/pathology , Murine hepatitis virus/physiology , Myelin Sheath , Interferons , Proteins/genetics , Spinal Cord/pathology , Multiple Sclerosis/pathology , Mice, Inbred C57BL , RNA-Binding Proteins/genetics , Apoptosis Regulatory Proteins/genetics
2.
Phytopathology ; 2024 May 29.
Article in English | MEDLINE | ID: mdl-38809758

ABSTRACT

Bacterial spot caused by Xanthomonas spp. is an economically important disease of pepper causing significant yield losses in Taiwan. Monitoring the pathogen population on a continuous basis is necessary for developing disease management strategies. We analyzed a collection of xanthomonad strains isolated from pepper in Taiwan between 1989 and 2019. Among the sequenced genomes, sixty-five were identified as Xanthomonas euvesicatoria and ten were X. perforans. Thirty-five X. euvesicatoria and ten X. perforans strains were copper tolerant, whereas only five X. euvesicatoria and none of the X. perforans strains were tolerant to streptomycin. Nine X. euvesicatoria strains were amylolytic, which is considered an unusual characteristic for X. euvesicatoria. Bayesian analysis of the population structure based on core gene SNPs clustered the strains into five clusters for X. euvesicatoria and three clusters for X. perforans. One X. perforans cluster, designated as TP-2019, appears to be a novel genetic cluster based on core genes, accessory gene content, and effector profile. This knowledge of pathogen diversity with whole genomic information will be useful in future comparative studies and in improving breeding programs to develop disease-resistant cultivars and other disease management options.

3.
J Immunol ; 206(7): 1483-1492, 2021 04 01.
Article in English | MEDLINE | ID: mdl-33685995

ABSTRACT

Patients with grade III anaplastic astrocytomas (AA) separate into survival cohorts based on the presence or absence of mutations in isocitrate dehydrogenase (IDH). Progression to glioblastoma (GBM), morphologically distinguishable by elevated microvascular proliferation, necrosis, and cell division in tumor tissues, is considerably more rapid in IDH wild-type tumors such that their diagnosis as AA is relatively rare. More often initially presenting as GBM, these contain higher numbers of tumor-associated macrophages (TAMs) than most AA, and GBM patients also have higher levels of circulating M2 monocytes. TAM and M2 monocytes share functional properties inhibitory for antitumor immunity. Yet, although there is a wealth of data implicating TAM in tumor-immune evasion, there has been limited analysis of the impact of the circulating M2 monocytes. In the current study, immune parameters in sera, circulating cells, and tumor tissues from patients with primary gliomas morphologically diagnosed as AA were assessed. Profound differences in serum cytokines, glioma extracellular vesicle cross-reactive Abs, and gene expression by circulating cells identified two distinct patient cohorts. Evidence of type 2-immune bias was most often seen in patients with IDH wild-type AA, whereas a type 1 bias was common in patients with tumors expressing the IDH1R132H mutation. Nevertheless, a patient's immune profile was better correlated with the extent of tumor vascular enhancement on magnetic resonance imaging than IDH mutational status. Regardless of IDH genotype, AA progression appears to be associated with a switch in systemic immune bias from type 1 to type 2 and the loss of tumor vasculature integrity.


Subject(s)
Astrocytoma/immunology , Glioblastoma/immunology , Tumor-Associated Macrophages/immunology , Adult , Cancer Survivors , Carcinogenesis , Cohort Studies , Cytokines/metabolism , Female , Humans , Isocitrate Dehydrogenase/genetics , Male , Middle Aged , Mutation/genetics , Th1 Cells/immunology , Th1-Th2 Balance , Th2 Cells/immunology
4.
Neuropathology ; 43(5): 391-395, 2023 Oct.
Article in English | MEDLINE | ID: mdl-36786200

ABSTRACT

Pilocytic astrocytoma (PA), a central nervous system (CNS) World Health Organization grade 1 tumor, is mainly seen in children or young adults aged 5-19. Surgical resection often provides excellent outcomes, but residual tumors may still remain. This low-grade tumor is well recognized for its classic radiological and morphological features; however, some unique molecular findings have been unveiled by the application of next-generation sequencing (NGS). Among the genetic abnormalities identified in this low-grade tumor, increasing evidence indicates that BRAF alterations, especially BRAF fusions, play an essential role in PA tumorigenesis. Among the several fusion partner genes identified in PAs, KIAA1549-BRAF fusion is notably the most common detectable genetic alteration, especially in the cerebellar PAs. Here, we report a case of a young adult patient with a large, right-sided posterior fossa cerebellar and cerebellopontine angle region mass consistent with a PA. Of note, NGS detected a novel GNAI3-BRAF fusion, which results in an in-frame fusion protein containing the kinase domain of BRAF. This finding expands the knowledge of BRAF fusions in the tumorigenesis of PAs, provides an additional molecular signature for diagnosis, and a target for future therapy.


Subject(s)
Astrocytoma , Brain Neoplasms , Central Nervous System Neoplasms , Child , Young Adult , Humans , Proto-Oncogene Proteins B-raf/genetics , Astrocytoma/diagnostic imaging , Astrocytoma/genetics , Astrocytoma/metabolism , Central Nervous System Neoplasms/genetics , Mutation , Carcinogenesis , Brain Neoplasms/diagnostic imaging , Brain Neoplasms/genetics , GTP-Binding Protein alpha Subunits, Gi-Go/genetics , GTP-Binding Protein alpha Subunits, Gi-Go/metabolism
5.
Br J Neurosurg ; 37(5): 1307-1310, 2023 Oct.
Article in English | MEDLINE | ID: mdl-33356599

ABSTRACT

Meningeal melanocytomas are rare, benign tumours of the central nervous system arising from the melanocytes of the leptomeninges. First-line treatment consists of either gross or subtotal resection with or without radiotherapy. However, given the sensitive locations of these tumours, alternative treatment options such as definitive radiotherapy may be warranted in patients deemed high-risk or without accessible tumours. A 67-year-old male presenting with spastic gait, frequent falls, and vertical gaze palsy was diagnosed with a 2.4 cm primary meningeal melanocytoma arising from the interpeduncular fossa. Given the critical tumour position within the brainstem, definitive radiotherapy was recommended. He received fractionated stereotactic radiotherapy (FSRT) to a total dose of 54 Gy in 27 fractions, resulting in a gradual improvement in gait and ocular range of motion. Follow-up imaging over the next three years revealed largely stable disease and an increase in edema with mild upper extremity weakness that improved with steroids. He was followed for three years and expired four years after treatment due to pneumonia. For patients unable to receive surgical resection, definitive RT may provide local control with minimal morbidity.


Subject(s)
Melanoma , Meningeal Neoplasms , Radiosurgery , Male , Adult , Humans , Aged , Melanoma/radiotherapy , Melanoma/surgery , Meningeal Neoplasms/diagnostic imaging , Meningeal Neoplasms/radiotherapy , Meningeal Neoplasms/surgery , Melanocytes/pathology , Central Nervous System/pathology
6.
BMC Pulm Med ; 22(1): 97, 2022 Mar 19.
Article in English | MEDLINE | ID: mdl-35305606

ABSTRACT

BACKGROUND: Neuromuscular pathologies must be considered when caring for patients with persistent or progressive respiratory failure. Pertinent disease states may involve skeletal muscles of respiration or associated neurologic structures including motor neurons, peripheral neurons and the neuromuscular junction. Diagnosis may require pulmonary function testing, neurophysiologic studies, imaging, and/or muscle biopsy. CASE PRESENTATION: A 68-year-old male was transferred to our intensive care unit (ICU) for management of ventilator dependent respiratory failure. Upon further historical review, he described gradually worsening gait instability and muscle weakness, which was previously attributed to vascular Parkinsonism in the setting of known cerebrovascular disease. Upon arrival to our hospital, he was found to have elevated muscle specific enzymes, prompting evaluation for neuromuscular causes of respiratory failure. He was also found to have elevated HMG-CoA Reductase (HMGCR) antibodies. Ultimately, a right quadriceps muscle biopsy was performed and electron microscopy identified nemaline bodies within skeletal myofibers. Given the clinical course and other histopathologic findings, he was diagnosed with Sporadic late-onset nemaline myopathy (SLONM). CONCLUSION: The diagnosis of neuromuscular disease in patients with ventilator dependent respiratory failure is challenging. A detailed history of a patient's clinical course prior to hospitalization is key and may raise suspicion for underlying neuromuscular pathology. Further evaluation in non-critically ill patients may include pulmonary function, electromyography and confirmatory muscle biopsy. Sporadic late onset nemaline myopathy remains a rare disease entity which rarely presents with respiratory failure and lacks effective treatment.


Subject(s)
Myopathies, Nemaline , Respiratory Insufficiency , Aged , Humans , Male , Muscle Weakness/etiology , Muscle, Skeletal/pathology , Myopathies, Nemaline/complications , Myopathies, Nemaline/diagnosis , Myopathies, Nemaline/pathology , Respiratory Insufficiency/etiology , Respiratory Insufficiency/pathology , Ventilators, Mechanical/adverse effects
7.
J Virol ; 94(14)2020 07 01.
Article in English | MEDLINE | ID: mdl-32404525

ABSTRACT

Mouse hepatitis virus (MHV) is a murine betacoronavirus (m-CoV) that causes a wide range of diseases in mice and rats, including hepatitis, enteritis, respiratory diseases, and encephalomyelitis in the central nervous system (CNS). MHV infection in mice provides an efficient cause-effect experimental model to understand the mechanisms of direct virus-induced neural-cell damage leading to demyelination and axonal loss, which are pathological features of multiple sclerosis (MS), the most common disabling neurological disease in young adults. Infiltration of T lymphocytes, activation of microglia, and their interplay are the primary pathophysiological events leading to disruption of the myelin sheath in MS. However, there is emerging evidence supporting gray matter involvement and degeneration in MS. The investigation of T cell function in the pathogenesis of deep gray matter damage is necessary. Here, we employed RSA59 (an isogenic recombinant strain of MHV-A59)-induced experimental neuroinflammation model to compare the disease in CD4-/- mice with that in CD4+/+ mice at days 5, 10, 15, and 30 postinfection (p.i.). Viral titer estimation, nucleocapsid gene amplification, and viral antinucleocapsid staining confirmed enhanced replication of the virions in the absence of functional CD4+ T cells in the brain. Histopathological analyses showed elevated susceptibility of CD4-/- mice to axonal degeneration in the CNS, with augmented progression of acute poliomyelitis and dorsal root ganglionic inflammation rarely observed in CD4+/+ mice. Depletion of CD4+ T cells showed unique pathological bulbar vacuolation in the brain parenchyma of infected mice with persistent CD11b+ microglia/macrophages in the inflamed regions on day 30 p.i. In summary, the current study suggests that CD4+ T cells are critical for controlling acute-stage poliomyelitis (gray matter inflammation), chronic axonal degeneration, and inflammatory demyelination due to loss of protective antiviral host immunity.IMPORTANCE The current trend in CNS disease biology is to attempt to understand the neural-cell-immune interaction to investigate the underlying mechanism of neuroinflammation, rather than focusing on peripheral immune activation. Most studies in MS are targeted toward understanding the involvement of CNS white matter. However, the importance of gray matter damage has become critical in understanding the long-term progressive neurological disorder. Our study highlights the importance of CD4+ T cells in safeguarding neurons against axonal blebbing and poliomyelitis from murine betacoronavirus-induced neuroinflammation. Current knowledge of the mechanisms that lead to gray matter damage in MS is limited, because the most widely used animal model, experimental autoimmune encephalomyelitis (EAE), does not present this aspect of the disease. Our results, therefore, add to the existing limited knowledge in the field. We also show that the microglia, though important for the initiation of neuroinflammation, cannot establish a protective host immune response without the help of CD4+ T cells.


Subject(s)
Axons/immunology , Axons/metabolism , CD4 Antigens/deficiency , Coronavirus Infections/immunology , Coronavirus Infections/virology , Murine hepatitis virus/physiology , Poliomyelitis/etiology , Animals , Axons/pathology , Brain/immunology , Brain/metabolism , Brain/pathology , CD4 Lymphocyte Count , CD4-Positive T-Lymphocytes/immunology , CD4-Positive T-Lymphocytes/metabolism , Coronavirus Infections/pathology , Cytokines/metabolism , Disease Models, Animal , Disease Susceptibility/immunology , Ganglia, Spinal/immunology , Ganglia, Spinal/metabolism , Ganglia, Spinal/pathology , Immunohistochemistry , Inflammation Mediators/metabolism , Mice
8.
Plant Dis ; 2021 Jan 16.
Article in English | MEDLINE | ID: mdl-33455442

ABSTRACT

Mungbean (Vigna radiata L.) is routinely grown in the experimental fields at the headquarters of the World Vegetable Center (23°6'30.88"N, 120°17'51.31"E) for breeding, research and germplasm multiplication. In a spring 2016 mungbean trial, about 50% of the plants were affected with powdery mildew. The white, powdery-like patches first appeared on the upper leaf surfaces, and soon developed to grey patches on both sides of the leaves. Purple to brown discoloration appeared on the underside of the infected leaf. Microscopy examination revealed that the causal organism was not Erysiphe polygoni, which had previously been documented as the powdery mildew pathogen on mungbean in Taiwan (Hartman et al. 1993). The fungus produced typical structures of the powdery mildew Euoidium, anamorph of the genus Podosphaera. The mycelium consisted of septate, flexuous hyphae with indistinct appressoria. The erect conidiophores arising from superficial hyphae varied from straight or slightly curved to curled. Three to ten conidia were borne in long chains with crenate edges. Foot-cells were straight, cylindrical and measured 30 to 52 µm long. Conidia were hyaline, ellipsoid-ovoid to barrel-shaped, with fibrosin bodies, and measured 27 to 33 (mean = 30.4) × 15 to 20 (mean = 16.6) µm. Germ tubes were clavate and occasionally forked, and were produced from the lateral sites of the conidia. No chasmothecia were found in the samples. The morphological characteristics were consistent with P. xanthii (Castagne) U. Braun & Shishkoff (Braun & Cook 2012). To confirm the identity, the internal transcribed spacer (ITS) region of rDNA and partialß-tubulin gene (TUB2) for the isolate MG3 were amplified with the primers ITS4/ITS5 (White et al. 1990) and BtuF5/BtuR7a (Ellingham et al. 2019), respectively. BLASTn analysis revealed the ITS sequence (MN833717) was 100% identical to many records of P. xanthii whereas the TUB2 sequence (MW363957) was 100% identical to a record of P. fusca (syn. P. xanthii; KC333362) in NCBI GenBank. A pathogenicity test was conducted by dusting conidia from an infected leaf onto six healthy four-week-old mungbean plants (cv 'Tainan No. 3'). Another three plants were not inoculated and were used as control. All the plants were maintained in a greenhouse at 25 to 28°C. All inoculated plants developed powdery mildew symptoms after 10 days, whereas the control plants remained symptomless. To our knowledge, this is the first report of P. xanthii causing disease on mungbean in Taiwan. P. xanthii also has been reported on mungbean in Thailand (Meeboon et al. 2016), while other records referring to E. polygoni infecting Vigna spp. are from Brazil and Fiji (Farr & Rossman 2020). Although both P. xanthii and E. polygoni have now been reported as causing powdery mildew on mungbean in Taiwan, which species predominates or is more important remains unclear. A comprehensive survey with accurate species identification is required to develop effective management of the disease, particularly for resistance breeding.

9.
J Biol Chem ; 294(20): 8064-8087, 2019 05 17.
Article in English | MEDLINE | ID: mdl-30824541

ABSTRACT

Fusion peptides (FPs) in spike proteins are key players mediating early events in cell-to-cell fusion, vital for intercellular viral spread. A proline residue located at the central FP region has often been suggested to have a distinctive role in this fusion event. The spike glycoprotein from strain RSA59 (PP) of mouse hepatitis virus (MHV) contains two central, consecutive prolines in the FP. Here, we report that deletion of one of these proline residues, resulting in RSA59 (P), significantly affected neural cell syncytia formation and viral titers postinfection in vitro Transcranial inoculation of C57Bl/6 mice with RSA59 (PP) or RSA59 (P) yielded similar degrees of necrotizing hepatitis and meningitis, but only RSA59 (PP) produced widespread encephalitis that extended deeply into the brain parenchyma. By day 6 postinfection, both virus variants were mostly cleared from the brain. Interestingly, inoculation with the RSA59 (P)-carrying MHV significantly reduced demyelination at the chronic stage. We also found that the presence of two consecutive prolines in FP promotes a more ordered, compact, and rigid structure in the spike protein. These effects on FP structure were due to proline's unique stereochemical properties intrinsic to its secondary amino acid structure, revealed by molecular dynamics and NMR experiments. We therefore propose that the differences in the severity of encephalitis and demyelination between RSA59 (PP) and RSA59 (P) arise from the presence or absence, respectively, of the two consecutive prolines in FP. Our studies define a structural determinant of MHV entry in the brain parenchyma important for altered neuropathogenesis.


Subject(s)
Brain , Demyelinating Diseases , INDEL Mutation , Meningitis, Viral , Murine hepatitis virus , Viral Envelope Proteins , Animals , Brain/metabolism , Brain/pathology , Brain/virology , Cell Line , Demyelinating Diseases/genetics , Demyelinating Diseases/metabolism , Demyelinating Diseases/pathology , Demyelinating Diseases/virology , Meningitis, Viral/genetics , Meningitis, Viral/metabolism , Meningitis, Viral/pathology , Meningitis, Viral/virology , Mice , Murine hepatitis virus/chemistry , Murine hepatitis virus/genetics , Murine hepatitis virus/metabolism , Nuclear Magnetic Resonance, Biomolecular , Proline , Protein Domains , Structure-Activity Relationship , Viral Envelope Proteins/chemistry , Viral Envelope Proteins/genetics , Viral Envelope Proteins/metabolism
10.
Histopathology ; 76(2): 275-282, 2020 Jan.
Article in English | MEDLINE | ID: mdl-31379028

ABSTRACT

AIMS: Cellular schwannoma is a specific subtype of schwannoma, prone to misinterpretation as a malignant neoplasm. Involvement of the intracranial compartment by these tumours is extremely rare. We aim to characterise this clinicopathological subgroup. METHODS AND RESULTS: We identified a total of 20 cellular schwannomas with predominant intracranial involvement. The mean age of the patients at the time of surgery was 37 years (range = 16-81), with a slight female predominance (1.5:1 ratio). The most common sites were the eighth (n = 8) and fifth (n = 6) cranial nerves. Three tumours involved the anterior cranial fossa/olfactory groove, and a single case involved the glossopharyngeal nerve. All tumours met established criteria for cellular schwannoma, and were composed of interlacing fascicles of spindle cells lacking Verocay bodies with minimal Antoni B pattern and variable chronic inflammation and foamy histiocytes. Rare findings included haemosiderin deposition (n = 6), necrosis (n = 4), brisk mitotic activity (>10 mitoses per 10 high-power fields) (n = 2), focal epithelioid morphology (n = 2), myxoid areas (n = 2), neuroblastoma-like pattern (n = 1) and granular cells (n = 1). Immunohistochemical stains demonstrated expression of Schwann cell markers (S100 protein, SOX10, collagen IV) and preserved H3 K27 trimethylation in all cases tested. Fourteen patients had postoperative follow-up, ranging from 2 months to 21 years (mean = 66 months). In patients with follow-up, local recurrence/persistence developed in six cases; five tumours were initially incompletely resected. No metastatic disease or deaths were reported. CONCLUSIONS: Intracranial cellular schwannomas share morphological and immunophenotypical features with cellular schwannomas at others sites may demonstrate locally aggressive growth but appear to lack metastatic potential.


Subject(s)
Biomarkers, Tumor/metabolism , Brain Neoplasms/pathology , Neurilemmoma/pathology , Adolescent , Adult , Aged , Aged, 80 and over , Brain Neoplasms/diagnostic imaging , Brain Neoplasms/metabolism , Female , Follow-Up Studies , Humans , Immunohistochemistry , Immunophenotyping , Male , Middle Aged , Neurilemmoma/diagnostic imaging , Neurilemmoma/metabolism , Young Adult
11.
Stem Cells ; 37(3): 395-406, 2019 03.
Article in English | MEDLINE | ID: mdl-30431198

ABSTRACT

It is well documented that adult neural stem cells (NSCs) residing in the subventricular zone (SVZ) and the subgranular zone (SGZ) are induced to proliferate and differentiate into new neurons after injury such as stroke and hypoxia. However, the role of injury-related cues in driving this process and the means by which they communicate with NSCs remains largely unknown. Recently, the coupling of neurogenesis and angiogenesis and the extensive close contact between vascular cells and other niche cells, known as the neurovascular unit (NVU), has attracted interest. Further facilitating communication between blood and NSCs is a permeable blood-brain-barrier (BBB) present in most niches, making vascular cells a potential conduit between systemic signals, such as vascular endothelial growth factor (VEGF), and NSCs in the niche, which could play an important role in regulating neurogenesis. We show that the leaky BBB in stem cell niches of the intact and stroke brain can respond to circulating VEGF165 to drive induction of the Notch ligand DLL4 (one of the most important cues in angiogenesis) in endothelial cells (ECs), pericytes, and further induce significant proliferation and neurogenesis of stem cells. Stem Cells 2019;37:395-406.


Subject(s)
Adult Stem Cells/metabolism , Blood-Brain Barrier/metabolism , Neovascularization, Physiologic , Neural Stem Cells/metabolism , Neurogenesis , Receptors, Notch/metabolism , Signal Transduction , Adult Stem Cells/cytology , Animals , Blood-Brain Barrier/cytology , Cell Line , Male , Mice , Neural Stem Cells/cytology , Rats , Rats, Sprague-Dawley , Vascular Endothelial Growth Factor A/metabolism
12.
Arch Virol ; 162(6): 1599-1607, 2017 Jun.
Article in English | MEDLINE | ID: mdl-28220324

ABSTRACT

Surveys were conducted in 2014 and 2015 in Southern and Northern Benin, respectively, to identify the viruses infecting peppers (Capsicum spp.). The samples were screened by ELISA for cucumber mosaic virus (CMV), pepper veinal mottle virus (PVMV), potato virus Y (PVY) and tomato yellow leaf curl virus (TYLCV). A generic reverse transcription PCR (RT-PCR) was used to test for the presence of poleroviruses. ELISA tests confirmed the prevalence of all viruses, while the RT-PCR detected pepper vein yellows virus (PeVYV) which is reported for the first time in Benin. A further, divergent polerovirus isolate was detected from a single pepper sample originating from southern Benin. Screening of samples collected from solanaceous plants during virus surveys in Mali (conducted in 2009) also detected this divergent polerovirus isolate in two samples from African eggplants. The complete genome sequence was obtained from the Mali isolate using transcriptome sequencing and by conventional Sanger sequencing of overlapping RT-PCR products. Based on the sequence characteristics of this isolate we propose a new polerovirus species, African eggplant yellowing virus (AeYV).


Subject(s)
Capsicum/virology , Luteoviridae/genetics , Luteoviridae/isolation & purification , Plant Diseases/virology , Benin , Cucumovirus/genetics , Enzyme-Linked Immunosorbent Assay/methods , Genome, Viral , Phylogeny , Polymerase Chain Reaction , Potyvirus/genetics , RNA, Viral , Sequence Analysis, DNA
13.
Am J Physiol Lung Cell Mol Physiol ; 310(4): L365-76, 2016 Feb 15.
Article in English | MEDLINE | ID: mdl-26684251

ABSTRACT

Airway remodeling is a hallmark feature of asthma and chronic obstructive pulmonary disease. Clinical studies and animal models have demonstrated increased airway smooth muscle (ASM) mass, and ASM thickness is correlated with severity of the disease. Current medications control inflammation and reverse airway obstruction effectively but have limited effect on remodeling. Recently we identified the expression of bitter taste receptors (TAS2R) on ASM cells, and activation with known TAS2R agonists resulted in ASM relaxation and bronchodilation. These studies suggest that TAS2R can be used as new therapeutic targets in the treatment of obstructive lung diseases. To further establish their effectiveness, in this study we aimed to determine the effects of TAS2R agonists on ASM growth and promitogenic signaling. Pretreatment of healthy and asthmatic human ASM cells with TAS2R agonists resulted in a dose-dependent inhibition of ASM proliferation. The antimitogenic effect of TAS2R ligands was not dependent on activation of protein kinase A, protein kinase C, or high/intermediate-conductance calcium-activated K(+) channels. Immunoblot analyses revealed that TAS2R agonists inhibit growth factor-activated protein kinase B phosphorylation without affecting the availability of phosphatidylinositol 3,4,5-trisphosphate, suggesting TAS2R agonists block signaling downstream of phosphatidylinositol 3-kinase. Furthermore, the antimitogenic effect of TAS2R agonists involved inhibition of induced transcription factors (activator protein-1, signal transducer and activator of transcription-3, E2 factor, nuclear factor of activated T cells) and inhibition of expression of multiple cell cycle regulatory genes, suggesting a direct inhibition of cell cycle progression. Collectively, these findings establish the antimitogenic effect of TAS2R agonists and identify a novel class of receptors and signaling pathways that can be targeted to reduce or prevent airway remodeling as well as bronchoconstriction in obstructive airway disease.


Subject(s)
Bronchodilator Agents/pharmacology , Muscle, Smooth/drug effects , Myocytes, Smooth Muscle/drug effects , Receptors, G-Protein-Coupled/agonists , Respiratory System/drug effects , Asthma/drug therapy , Asthma/metabolism , Bronchoconstriction/drug effects , Calcium Signaling/drug effects , Humans , Muscle, Smooth/metabolism , Myocytes, Smooth Muscle/metabolism , Phosphatidylinositol 3-Kinases/metabolism , Respiratory System/metabolism , Taste/physiology
14.
Clin Immunol ; 170: 9-19, 2016 09.
Article in English | MEDLINE | ID: mdl-27394164

ABSTRACT

The presence of immunoglobulin oligoclonal bands in the cerebrospinal fluid of Multiple Sclerosis (MS) patients supports the hypothesis of an infectious etiology, although the antigenic targets remain elusive. Neurotropic mouse hepatitis virus (MHV) infection in mice provides a useful tool for studying mechanisms of demyelination in a virus-induced experimental model of MS. This study uses Affymetrix microarray analysis to compare differential spinal cord mRNA levels between mice infected with demyelinating and non-demyelinating strains of MHV to identify host immune genes expressed in this demyelinating disease model. The study reveals that during the acute stage of infection, both strains induce inflammatory innate immune response genes, whereas upregulation of several immunoglobulin genes during chronic stage infection is unique to infection with the demyelinating strain. Results suggest that the demyelinating strain induced an innate-immune response during acute infection that may promote switching of Ig isotype genes during chronic infection, potentially playing a role in antibody-mediated progressive demyelination even after viral clearance.


Subject(s)
Adaptive Immunity/genetics , Coronavirus Infections/genetics , Demyelinating Diseases/genetics , Gene Expression Regulation/genetics , Immunity, Innate/genetics , Animals , Coronavirus Infections/immunology , Coronavirus Infections/virology , Demyelinating Diseases/immunology , Demyelinating Diseases/virology , Gene Expression Profiling/methods , Gene Expression Regulation/immunology , Host-Pathogen Interactions/immunology , Immunohistochemistry , Mice, Inbred C57BL , Murine hepatitis virus/immunology , Murine hepatitis virus/physiology , Oligonucleotide Array Sequence Analysis , Reverse Transcriptase Polymerase Chain Reaction , Spinal Cord/immunology , Spinal Cord/metabolism , Spinal Cord/virology
15.
Cancer Immunol Immunother ; 64(3): 299-309, 2015 Mar.
Article in English | MEDLINE | ID: mdl-25391690

ABSTRACT

Glioblastomas are primary intracranial tumors for which there is no cure. Patients receiving standard of care, chemotherapy and irradiation, survive approximately 15 months prompting studies of alternative therapies including vaccination. In a pilot study, a vaccine consisting of Lucite diffusion chambers containing irradiated autologous tumor cells pre-treated with an antisense oligodeoxynucleotide (AS-ODN) directed against the insulin-like growth factor type 1 receptor was found to elicit positive clinical responses in 8/12 patients when implanted in the rectus sheath for 24 h. Our preliminary observations supported an immune response, and we have since reopened a second Phase 1 trial to assess this possibility among other exploratory objectives. The current study makes use of a murine glioma model and samples from glioblastoma patients in this second Phase 1 trial to investigate this novel therapeutic intervention more thoroughly. Implantation of the chamber-based vaccine protected mice from tumor challenge, and we posit this occurred through the release of immunostimulatory AS-ODN and antigen-bearing exosomes. Exosomes secreted by glioblastoma cultures are immunogenic, eliciting and binding antibodies present in the sera of immunized mice. Similarly, exosomes released by human glioblastoma cells bear antigens recognized by the sera of 6/12 patients with recurrent glioblastomas. These results suggest that the release of AS-ODN together with selective release of exosomes from glioblastoma cells implanted in chambers may drive the therapeutic effect seen in the pilot vaccine trial.


Subject(s)
Brain Neoplasms/therapy , Exosomes/immunology , Glioblastoma/therapy , Immunotherapy/methods , Oligodeoxyribonucleotides, Antisense/administration & dosage , Receptor, IGF Type 1/immunology , Animals , Brain Neoplasms/immunology , Brain Neoplasms/pathology , Cell Line, Tumor , Glioblastoma/immunology , Glioblastoma/pathology , Humans , Male , Mice , Mice, Inbred C57BL , Oligodeoxyribonucleotides, Antisense/genetics , Oligodeoxyribonucleotides, Antisense/immunology , Receptor, IGF Type 1/genetics , Translational Research, Biomedical , Xenograft Model Antitumor Assays
16.
Arch Virol ; 160(10): 2633-6, 2015 Oct.
Article in English | MEDLINE | ID: mdl-26195192

ABSTRACT

Luffa aphid-borne yellows virus (LABYV) was proposed as the name for a previously undescribed polerovirus based on partial genome sequences obtained from samples of cucurbit plants collected in Thailand between 2008 and 2013. In this study, we determined the first full-length genome sequence of LABYV. Based on phylogenetic analysis and genome properties, it is clear that this virus represents a distinct species in the genus Polerovirus. Analysis of sequences from sample TH24, which was collected in 2010 from a luffa plant in Thailand, reveals the presence of two different full-length genome consensus sequences.


Subject(s)
Genome, Viral , Luffa/virology , Luteoviridae/genetics , Luteoviridae/isolation & purification , Base Sequence , Consensus Sequence , Luteoviridae/classification , Molecular Sequence Data , Open Reading Frames , Phylogeny , Thailand
17.
Arch Virol ; 158(6): 1337-41, 2013 Jun.
Article in English | MEDLINE | ID: mdl-23307365

ABSTRACT

Polerovirus infection was detected by reverse transcription polymerase chain reaction (RT-PCR) in 29 pepper plants (Capsicum spp.) and one black nightshade plant (Solanum nigrum) sample collected from fields in India, Indonesia, Mali, Philippines, Thailand and Taiwan. At least two representative samples for each country were selected to generate a general polerovirus RT-PCR product of 1.4 kb length for sequencing. Sequence analysis of the partial genome sequences revealed the presence of pepper vein yellows virus (PeVYV) in all 13 samples. A 1990 Australian herbarium sample of pepper described by serological means as infected with capsicum yellows virus (CYV) was identified by sequence analysis of a partial CP sequence as probably infected with a potato leaf roll virus (PLRV) isolate.


Subject(s)
Capsicum/virology , Luteoviridae/genetics , Plant Diseases/virology , Genome, Viral/genetics , India , Indonesia , Mali , Philippines , Plant Diseases/statistics & numerical data , Reverse Transcriptase Polymerase Chain Reaction , Sequence Analysis, DNA , Taiwan , Thailand
18.
Front Plant Sci ; 14: 1116006, 2023.
Article in English | MEDLINE | ID: mdl-37360710

ABSTRACT

Fusarium wilt is a serious disease of cucurbit crops including cultivated Luffa species (Luffa aegyptiaca, Luffa acutangula) causing considerable amount of reduction in yield and quality. Luffa is starting to be used as rootstocks for major commercial cucurbit crops, but little is known of its resistance against soilborne diseases. Here, 63 Luffa accessions from the World Vegetable Center genebank were evaluated for resistance to an aggressive isolate of Fusarium oxysporum f. FoCu-1 (Fsp-66). According to visual screening based on disease severity rating, 14 accessions exhibited a high level of resistance against Fsp-66. These accessions were further evaluated for resistance against Fsp-66 and two more isolates FoCu-1 (isolated from infected cucumber plants) and FoM-6 (isolated from infected bitter gourd plants). Of the 14 accessions, 11 were confirmed resistant against isolate Fsp-66. In addition, 13 accessions showed high resistance against isolates FoCu-1 and FoM-6. This is the first report of Fusarium wilt resistance in Luffa and these sources will be valuable for the development of Luffa rootstocks/cultivars resistant to soil-borne pathogen to manage this serious disease.

19.
J Med Case Rep ; 17(1): 102, 2023 Mar 20.
Article in English | MEDLINE | ID: mdl-36935497

ABSTRACT

BACKGROUND: Hemangioblastoma of the central nervous system is an uncommon benign neoplasm, with about 25% of cases in patients with von Hippel-Lindau disease. The incidence of metastasis is rare, particularly in patients without von Hippel-Lindau disease. We report a case of hemangioblastoma with leptomeningeal dissemination as a late recurrence. CASE PRESENTATION: A 65-year-old Caucasian man with a history of World Health Organization grade I hemangioblastoma of the cerebellar vermis underwent gross total resection in 1997. In early 2018, he developed intracranial recurrences with diffuse leptomeningeal disease of the entire spine. The patient underwent resection of intracranial recurrence, followed by palliative craniospinal irradiation. The disease progressed quickly, and he died 8 months after recurrence. CONCLUSIONS: Despite a benign pathology, hemangioblastoma has a low risk of metastasis. The outcome for hemangioblastoma patients with metastasis is poor. Multidisciplinary care for patients with metastatic hemangioblastoma warrants further investigation, and an effective systemic option is urgently needed. Regular lifelong follow-up of at-risk patients is recommended.


Subject(s)
Cerebellar Neoplasms , Hemangioblastoma , von Hippel-Lindau Disease , Male , Humans , Aged , Hemangioblastoma/surgery , Cerebellar Neoplasms/surgery , Spine
20.
Neurooncol Adv ; 4(1): vdac152, 2022.
Article in English | MEDLINE | ID: mdl-36299794

ABSTRACT

Background: We sought to identify clinical and genetic predictors of temozolomide-related myelotoxicity among patients receiving therapy for glioblastoma. Methods: Patients (n = 591) receiving therapy on NRG Oncology/RTOG 0825 were included in the analysis. Cases were patients with severe myelotoxicity (grade 3 and higher leukopenia, neutropenia, and/or thrombocytopenia); controls were patients without such toxicity. A risk-prediction model was built and cross-validated by logistic regression using only clinical variables and extended using polymorphisms associated with myelotoxicity. Results: 23% of patients developed myelotoxicity (n = 134). This toxicity was first reported during the concurrent phase of therapy for 56 patients; 30 stopped treatment due to toxicity. Among those who continued therapy (n = 26), 11 experienced myelotoxicity again. The final multivariable clinical factor model included treatment arm, gender, and anticonvulsant status and had low prediction accuracy (area under the curve [AUC] = 0.672). The final extended risk prediction model including four polymorphisms in MGMT had better prediction (AUC = 0.827). Receiving combination chemotherapy (OR, 1.82; 95% CI, 1.02-3.27) and being female (OR, 4.45; 95% CI, 2.45-8.08) significantly increased myelotoxicity risk. For each additional minor allele in the polymorphisms, the risk increased by 64% (OR, 1.64; 95% CI, 1.43-1.89). Conclusions: Myelotoxicity during concurrent chemoradiation with temozolomide is an uncommon but serious event, often leading to treatment cessation. Successful prediction of toxicity may lead to more cost-effective individualized monitoring of at-risk subjects. The addition of genetic factors greatly enhanced our ability to predict toxicity among a group of similarly treated glioblastoma patients.

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