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1.
Nat Commun ; 12(1): 216, 2021 01 11.
Article in English | MEDLINE | ID: mdl-33431849

ABSTRACT

While a number of human coronaviruses are believed to be originated from ancestral viruses in bats, it remains unclear if bat coronaviruses are ready to cause direct bat-to-human transmission. Here, we report the isolation of a MERS-related coronavirus, Tylonycteris-bat-CoV-HKU4, from lesser bamboo bats. Tylonycteris-bat-CoV-HKU4 replicates efficiently in human colorectal adenocarcinoma and hepatocarcinoma cells with cytopathic effects, and can utilize human-dipeptidyl-peptidase-4 and dromedary camel-dipeptidyl-peptidase-4 as the receptors for cell entry. Flow cytometry, co-immunoprecipitation and surface plasmon resonance assays show that Tylonycteris-bat-CoV-HKU4-receptor-binding-domain can bind human-dipeptidyl-peptidase-4, dromedary camel-dipeptidyl-peptidase-4, and Tylonycteris pachypus-dipeptidyl-peptidase-4. Tylonycteris-bat-CoV-HKU4 can infect human-dipeptidyl-peptidase-4-transgenic mice by intranasal inoculation with self-limiting disease. Positive virus and inflammatory changes were detected in lungs and brains of infected mice, associated with suppression of antiviral cytokines and activation of proinflammatory cytokines and chemokines. The results suggest that MERS-related bat coronaviruses may overcome species barrier by utilizing dipeptidyl-peptidase-4 and potentially emerge in humans by direct bat-to-human transmission.


Subject(s)
Chiroptera/virology , Coronavirus Infections/virology , Dipeptidyl Peptidase 4/metabolism , Middle East Respiratory Syndrome Coronavirus/isolation & purification , Animals , Brain/pathology , Caco-2 Cells , Coronavirus Infections/immunology , Coronavirus Infections/pathology , Coronavirus Infections/transmission , Cytokines/metabolism , Dipeptidyl Peptidase 4/genetics , HEK293 Cells , Host Specificity , Humans , Lung/pathology , Mice , Mice, Inbred C57BL , Mice, Transgenic , Middle East Respiratory Syndrome Coronavirus/genetics
2.
mBio ; 9(3)2018 06 12.
Article in English | MEDLINE | ID: mdl-29895639

ABSTRACT

Talaromyces marneffei is the most important thermal dimorphic fungus causing systemic mycosis in Southeast Asia. We report the discovery of a novel partitivirus, Talaromyces marneffeipartitivirus-1 (TmPV1). TmPV1 was detected in 7 (12.7%) of 55 clinical T. marneffei isolates. Complete genome sequencing of the seven TmPV1 isolates revealed two double-stranded RNA (dsRNA) segments encoding RNA-dependent RNA polymerase (RdRp) and capsid protein, respectively. Phylogenetic analysis showed that TmPV1 occupied a distinct clade among the members of the genus Gammapartitivirus Transmission electron microscopy confirmed the presence of isometric, nonenveloped viral particles of 30 to 45 nm in diameter, compatible with partitiviruses, in TmPV1-infected T. marneffei Quantitative reverse transcription-PCR (qRT-PCR) demonstrated higher viral load of TmPV1 in the yeast phase than in the mycelial phase of T. marneffei Two virus-free isolates, PM1 and PM41, were successfully infected by purified TmPV1 using protoplast transfection. Mice challenged with TmPV1-infected T. marneffei isolates showed significantly shortened survival time (P < 0.0001) and higher fungal burden in organs than mice challenged with isogenic TmPV1-free isolates. Transcriptomic analysis showed that TmPV1 causes aberrant expression of various genes in T. marneffei, with upregulation of potential virulence factors and suppression of RNA interference (RNAi)-related genes. This is the first report of a mycovirus in a thermally dimorphic fungus. Further studies are required to ascertain the mechanism whereby TmPV1 enhances the virulence of T. marneffei in mice and the potential role of RNAi-related genes in antiviral defense in T. marneffeiIMPORTANCETalaromyces marneffei (formerly Penicillium marneffei) is the most important thermal dimorphic fungus in Southeast Asia, causing highly fatal systemic penicilliosis in HIV-infected and immunocompromised patients. We discovered a novel mycovirus, TmPV1, in seven clinical isolates of T. marneffei TmPV1 belongs to the genus Gammapartitivirus of the family Partitiviridae We showed that TmPV1 enhanced the virulence of T. marneffei in mice, with shortened survival time and higher fungal burden in the organs of mice challenged with TmPV1-infected T. marneffei isolates than in those of mice challenged with virus-free isogenic isolates. Transcriptomics analysis showed that TmPV1 altered the expression of genes involved in various cellular processes in T. marneffei, with upregulation of potential virulence factors and suppression of RNAi machinery which may be involved in antiviral defense. This is the first report of a mycovirus in a thermal dimorphic fungus. The present results offer insights into mycovirus-fungus interactions and pathogenesis of thermal dimorphic fungi.


Subject(s)
Fungal Viruses/isolation & purification , Mycoses/microbiology , RNA Viruses/isolation & purification , RNA Viruses/physiology , Talaromyces/pathogenicity , Talaromyces/virology , Animals , Female , Fungal Proteins/genetics , Fungal Proteins/metabolism , Fungal Viruses/classification , Fungal Viruses/genetics , Fungal Viruses/physiology , Humans , Mice , Mice, Inbred BALB C , Phylogeny , RNA Viruses/classification , RNA Viruses/genetics , Talaromyces/genetics , Talaromyces/physiology , Viral Proteins/genetics , Viral Proteins/metabolism , Virulence , Virulence Factors/genetics , Virulence Factors/metabolism
3.
Article in English | MEDLINE | ID: mdl-28031205

ABSTRACT

We determined the susceptibilities of 57 Talaromyces marneffei strains to anidulafungin, itraconazole, voriconazole, and posaconazole with MICs of 2 to 8, 0.002 to 0.004, 0.016 to 0.063, and 0.001 to 0.002 µg/ml by broth microdilution and >32, ≤0.002 to 0.008, ≤0.002 to 0.008, and ≤0.002 µg/ml by Etest, respectively, at yeast phase; MICs at mycelial phase for anidulafungin and posaconazole were 1 to 2 and 0.004 to 0.063 µg/ml, respectively. The results suggest promising activities of posaconazole. Etest can be used for testing of azoles against T. marneffei.


Subject(s)
Antifungal Agents/pharmacology , Echinocandins/pharmacology , Itraconazole/pharmacology , Talaromyces/drug effects , Triazoles/pharmacology , Voriconazole/pharmacology , Anidulafungin , Disk Diffusion Antimicrobial Tests , Humans , Penicillium/drug effects , Penicillium/growth & development , Reagent Strips , Talaromyces/growth & development , Talaromyces/isolation & purification
4.
Int J Mol Sci ; 17(3): 307, 2016 Feb 27.
Article in English | MEDLINE | ID: mdl-26927094

ABSTRACT

To identify potential biomarkers for improving diagnosis of melioidosis, we compared plasma metabolome profiles of melioidosis patients compared to patients with other bacteremia and controls without active infection, using ultra-high-performance liquid chromatography-electrospray ionization-quadruple time-of-flight mass spectrometry. Principal component analysis (PCA) showed that the metabolomic profiles of melioidosis patients are distinguishable from bacteremia patients and controls. Using multivariate and univariate analysis, 12 significant metabolites from four lipid classes, acylcarnitine (n = 6), lysophosphatidylethanolamine (LysoPE) (n = 3), sphingomyelins (SM) (n = 2) and phosphatidylcholine (PC) (n = 1), with significantly higher levels in melioidosis patients than bacteremia patients and controls, were identified. Ten of the 12 metabolites showed area-under-receiver operating characteristic curve (AUC) >0.80 when compared both between melioidosis and bacteremia patients, and between melioidosis patients and controls. SM(d18:2/16:0) possessed the largest AUC when compared, both between melioidosis and bacteremia patients (AUC 0.998, sensitivity 100% and specificity 91.7%), and between melioidosis patients and controls (AUC 1.000, sensitivity 96.7% and specificity 100%). Our results indicate that metabolome profiling might serve as a promising approach for diagnosis of melioidosis using patient plasma, with SM(d18:2/16:0) representing a potential biomarker. Since the 12 metabolites were related to various pathways for energy and lipid metabolism, further studies may reveal their possible role in the pathogenesis and host response in melioidosis.


Subject(s)
Melioidosis/blood , Metabolome , Sphingomyelins/blood , Bacteremia/blood , Biomarkers/blood , Carnitine/analogs & derivatives , Carnitine/blood , Case-Control Studies , Humans , Phosphatidylcholines/blood
5.
Sensors (Basel) ; 7(11): 2881-2906, 2007 Nov 20.
Article in English | MEDLINE | ID: mdl-28903267

ABSTRACT

This study examines the temporal and spatial changes in land use as aconsequence of rapid urban development in the city of Beijing. Using a combination oftechniques of remote sensing and GIS, the study identifies a substantial loss of plaindryland and a phenomenal expansion of urban construction land over the recent decade.Geographically, there is a clear shifting of urban construction land from the inner city tothe outskirts as a consequence of suburbanization. The outward expansion of the ring-roadsystem is found to be one of the most important driving forces explaining the temporal andspatial pattern of land use change. The uneven distribution of population stands as anotherfactor with significant correlation with land use change. The application of the techniquesof remote sensing and GIS can enhance the precision and comparability of research onland use change and urban transformation in China.

6.
Ann Oncol ; 13(10): 1576-82, 2002 Oct.
Article in English | MEDLINE | ID: mdl-12377645

ABSTRACT

BACKGROUND: Eniluracil is a potent, irreversible inactivator of dihydropyrimidine dehydrogenase, the major catabolic enzyme for 5-fluorouracil (5-FU). Pretreatment with eniluracil significantly increases plasma half-life, plasma concentration and oral bioavailability of 5-FU. This multicenter phase II trial was designed to estimate the 6-month survival rate in patients with metastatic adenocarcinoma of the pancreas treated with 5-FU and eniluracil. PATIENTS AND METHODS: One hundred and sixteen patients (61 with no prior chemotherapy and 55 with prior chemotherapy) were registered for treatment with eniluracil 50 mg (total dose) p.o. on days 1-7 and 5-FU 20 mg/m(2)/day p.o. on days 2-6 of a 28-day treatment cycle. RESULTS: In 106 patients evaluable for survival, the 6-month survival rate was 34% [95% confidence interval (CI) 22% to 47%, median survival 3.6 months] for patients who had not been treated previously with chemotherapy and 29% (95% CI 16% to 42%, median survival 3.4 months) for those who had received prior chemotherapy. For those patients with measurable disease, the confirmed response rates were 8% and 2%, respectively. The most common grade 3-4 toxicities were neutropenia (29% of patients) and diarrhea (12% of patients). Overall, 69% of patients experienced a grade 3 or worse adverse event during treatment. CONCLUSIONS: These results suggest that the combination of a 7-day course of eniluracil and a 5-day course of oral 5-FU has limited activity in patients with advanced pancreatic cancer, and is associated with a high frequency of clinically significant adverse events.


Subject(s)
Adenocarcinoma/drug therapy , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Pancreatic Neoplasms/drug therapy , Uracil/analogs & derivatives , Adenocarcinoma/pathology , Administration, Oral , Adult , Aged , Antineoplastic Combined Chemotherapy Protocols/adverse effects , Diarrhea/chemically induced , Enzyme Inhibitors/administration & dosage , Enzyme Inhibitors/pharmacology , Female , Fluorouracil/administration & dosage , Humans , Male , Middle Aged , Neoplasm Metastasis , Neutropenia/chemically induced , Pancreatic Neoplasms/pathology , Survival , Treatment Outcome , Uracil/administration & dosage , Uracil/pharmacology
7.
Rheum Dis Clin North Am ; 23(2): 425-37, 1997 May.
Article in English | MEDLINE | ID: mdl-9156401

ABSTRACT

Hematologic side effects of rheumatic disease therapies are generally mild and reversible; however, the clinician must be alert for potential profound and life-threatening toxicities. A knowledge of the toxicity patterns for the individual drugs is necessary to anticipate potential complications. Management of acute leukemias and lymphomas arising in patients with connective tissue disorders is particularly challenging. Further data are needed to define the best treatment options and thus enrollment in clinical trials is encouraged for these patients.


Subject(s)
Antirheumatic Agents/adverse effects , Hematologic Diseases/chemically induced , Neoplasms, Second Primary/chemically induced , Rheumatic Diseases/drug therapy , Anemia/chemically induced , Anemia/therapy , Humans , Immunocompromised Host , Leukemia/chemically induced , Leukopenia/chemically induced , Leukopenia/therapy , Lymphoma/chemically induced
8.
J Bacteriol ; 162(2): 661-7, 1985 May.
Article in English | MEDLINE | ID: mdl-3886630

ABSTRACT

A locus unlinked to either katE or katF that affected catalase levels in Escherichia coli was identified and localized between metB and ppc at 89.2 min on the genome. The locus was named katG. Mutations in katG which prevented the formation of both isoenzyme forms of the bifunctional catalase-peroxidase HPI were created both by nitrosoguanidine and by transposon Tn10 insertions. All katG+ recombinants and transductants contained both HPI isoenzymes. Despite the common feature of little or no catalase activity in four of the catalase-deficient strains, subtle differences in the phenotypes of each strain resulted from the different katG mutations. All three mutants caused by nitrosoguanidine produced a protein with little or no catalase activity but with the same subunit molecular weight and with similar antigenic properties to HPI, implying the presence of missense mutations rather than nonsense mutations in each strain. Indeed one mutant produced an HPI-like protein that retained peroxidase activity, whereas the HPI-like protein in a second mutant exhibited no catalase or peroxidase activity. The third mutant responded to ascorbate induction with the synthesis of near normal catalase levels, suggesting a regulatory defect. The Tn10 insertion mutant produced no catalase and no protein that was antigenically similar to HPI.


Subject(s)
Catalase/genetics , Escherichia coli/genetics , Catalase/immunology , Chromosome Mapping , DNA, Bacterial/genetics , Escherichia coli/enzymology , Genes, Bacterial , Isoenzymes/genetics , Peroxidases/genetics , Phenotype
9.
AANA J ; 44(5): 513-6, 1976 Oct.
Article in English | MEDLINE | ID: mdl-1049501
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