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1.
BMC Microbiol ; 22(1): 17, 2022 01 07.
Article in English | MEDLINE | ID: mdl-34996353

ABSTRACT

BACKGROUND: Xanthomonas campestris pv. campestris (Xcc) is a Gram-negative bacterium that can cause black rot disease in crucifers. The lipoprotein outer membrane localization (Lol) system is involved in the lipoprotein sorting to the outer membrane. Although Xcc has a set of annotated lol genes, there is still little known about the physiological role in this phytopathogen. In this study, we aimed to characterize the role of LolB of Xcc in bacterial attachment, stress tolerance, and virulence. RESULTS: To characterize the role of LolB, lolB mutant was constructed and phenotypic evaluation was performed. The lolB mutant revealed reductions in bacterial attachment, extracellular enzyme production, and virulence. Mutation of lolB also resulted in reduced tolerance to a myriad of stresses, including heat and a range of membrane-perturbing agents. Trans-complementation of lolB mutant with intact lolB gene reverted these altered phenotypes to the wild-type levels. From subsequent reporter assay and reverse transcription quantitative real-time polymerase chain reaction (RT-qPCR) analysis, the expression of genes that encode the major extracellular enzymes and the stress-related proteins was reduced after lolB mutation. CONCLUSIONS: The results in this work contribute to the functional understanding of lolB in Xanthomonas for the first time, and provide new insights into the function of lolB in bacteria.


Subject(s)
Bacterial Outer Membrane Proteins/genetics , Xanthomonas campestris/physiology , Xanthomonas campestris/pathogenicity , Adaptation, Physiological/genetics , Bacterial Adhesion/genetics , Cell Membrane/genetics , Cell Membrane/metabolism , Gene Expression Regulation, Bacterial/genetics , Lipoproteins/genetics , Lipoproteins/metabolism , Mutation , Plant Diseases/microbiology , Virulence/genetics , Xanthomonas campestris/genetics , Xanthomonas campestris/metabolism
2.
iScience ; 24(2): 102034, 2021 Feb 19.
Article in English | MEDLINE | ID: mdl-33554057

ABSTRACT

Human mitochondrial NAD(P)+-dependent malic enzyme (ME2) is well recognized to associate with cancer cell metabolism, and the single nucleotide variants (SNVs) of ME2 may play a role in enzyme regulation. Here we reported that the SNVs of ME2 occurring in the allosteric sites lead to inactivation or overactivation of ME2. Two ME2-SNVs, ME2_R67Q and ME2-R484W, that demonstrated inactivating or overactivating enzyme activities of ME2, respectively, have different impact toward the cells. The cells with overactivating SNV enzyme, ME2_R484W, grow more rapidly and are more resistant to cellular senescence than the cells with wild-type or inactivating SNV enzyme, ME2_R67Q. Crystal structures of these two ME2-SNVs reveal that ME2_R67Q was an inactivating "dead form," and ME2_R484W was an overactivating "closed form" of the enzyme. The resolved ME2-SNV structures provide a molecular basis to explain the abnormal kinetic properties of these SNV enzymes.

3.
Front Med (Lausanne) ; 7: 601606, 2020.
Article in English | MEDLINE | ID: mdl-33693010

ABSTRACT

Objectives: Women affected by rheumatoid arthritis (RA) have a higher risk of endometriosis, an estrogen-dependent, chronic inflammatory disease. Though acupuncture has long been a safe and effective therapy for treating inflammatory conditions, it is unclear whether it could prevent the onset of endometriosis. This study aims to determine the effect of acupuncture on the subsequent risk of endometriosis in female RA patients. Methods: Between 1998 and 2010, female subjects with RA were recruited from a nationwide database (5,736 patients; age ≥20 years). Enrolled patients included 2,407 acupuncture users and 2,407 nonusers randomly selected using propensity scores. The occurrence of endometriosis was recorded through the end of 2012. Cox proportional hazards regression was used to estimate the adjusted hazard ratio (HR) associated with acupuncture use. Results: During the follow-up period, 35 acupuncture users and 94 non-users developed endometriosis, with incidence rates of 2.36 and 4.91 per 1,000 person-years, respectively. Acupuncture use was associated with a 55% lower endometriosis risk (adjusted HR, 0.45; 95% confidence interval, 0.31-0.65). Those who received high intensity acupuncture (≥15 packages) had the greatest benefit. Conclusions: Findings suggest that adding acupuncture to conventional therapy may decrease the subsequent endometriosis risk in female RA patients. Prospective randomized trials are recommended to further clarify whether the association revealed in this study supports a causal link.

4.
J Formos Med Assoc ; 111(6): 347-9, 2012 Jun.
Article in English | MEDLINE | ID: mdl-22748626

ABSTRACT

Crohn disease is a chronic inflammatory disorder, which is rare in pediatric patients. The definite etiology and mechanism to induce an acute exacerbation of Crohn disease remains mostly unknown. The authors report on a 14-year-old girl with Crohn disease who has acute gastrointestinal symptoms caused by toxin A-producing Clostridium difficile, which mimicked a flare-up of Crohn disease. There was no preceding antibiotic prescription before the episode. The disease activity did not improve after steroid treatment, which is unusual for Crohn disease. However, all symptoms were dramatically relieved after eradication of C difficile, and led to a symptom-free period for more than 3 years. This case report aims to address the unusual presentation of a usual pathogen, C difficile, in a pediatric patient with Crohn disease.


Subject(s)
Clostridioides difficile/isolation & purification , Clostridium Infections/diagnosis , Crohn Disease/complications , Adolescent , Clostridium Infections/complications , Disease Progression , Female , Humans
5.
J Microbiol Immunol Infect ; 45(3): 185-92, 2012 Jun.
Article in English | MEDLINE | ID: mdl-22571996

ABSTRACT

BACKGROUND/PURPOSE: Human papillomavirus (HPV) infection can cause laryngeal papillomas in children. Vertical transmission has been confirmed. This study aimed to establish a sensitive molecular diagnostic method and understand the incidence of the HPV-6 and HPV-11 in neonates with intubation. METHODS: We enrolled 108 newborns between October 2007 and January 2010. All neonates were intubated due to underlying disease. The specimens were collected via endotracheal aspiration. DNA of HPV types 6 and 11 was detected by real-time PCR and nested PCR. RESULTS: HPV-DNA was detected in eight of the 108 newborns studied. Seven respiratory specimens tested positive for HPV-11 and one was positive for HPV-6. The HPV 6/11 detection rate in neonates was 7.4% (8/108). CONCLUSION: A rapid, sensitive, specific, and reproducible RT-PCR method and nest PCR were developed for the detection and differentiation of HPV-6 and HPV-11 genomic variants in a single PCR reaction. The assays are of great value for clinical and epidemiologic studies of HPV-6 and HPV-11 infections. Neonatal HPV colonization may be related to juvenile-onset recurrent respiratory papillomatosis. The transmission route may be from mother to child. The clinical significance of neonatal carriage of HPV-6 or HPV-11 warrants further study.


Subject(s)
Human papillomavirus 11/isolation & purification , Human papillomavirus 6/isolation & purification , Molecular Diagnostic Techniques/methods , Papillomavirus Infections/virology , Academic Medical Centers , Base Sequence , Cohort Studies , DNA, Viral/analysis , DNA, Viral/isolation & purification , Human papillomavirus 11/genetics , Human papillomavirus 6/genetics , Humans , Incidence , Infant, Newborn , Intubation, Intratracheal/statistics & numerical data , Molecular Sequence Data , Pilot Projects , Reproducibility of Results , Reverse Transcriptase Polymerase Chain Reaction/methods , Sensitivity and Specificity , Sequence Alignment
6.
Cancer Prev Res (Phila) ; 5(3): 444-52, 2012 Mar.
Article in English | MEDLINE | ID: mdl-22135043

ABSTRACT

Adoptive T-cell therapy involves the ex vivo expansion and subsequent transfusion of tumor-specific T lymphocytes to eliminate tumors. Using immune modulators to block immunosuppressive factors in the tumor microenvironment has emerged as a promising strategy to enhance T-cell-mediated tumor regression. Curcumin, a major component of turmeric, has been shown to possess antitumor and immunomodulatory effects by regulating a diverse range of molecular targets. Thus, we hypothesize that these beneficial effects of curcumin may improve the therapeutic efficacy of adoptive therapy. Here, we have shown that curcumin enhances cytotoxicity of CD8(+) T cells toward tumors via alteration of the tumor microenvironment when combined with adoptive therapy. We found that T-cell accumulation and function were increased in combined treatment due to the blockade of different immunosuppressors, including TGF-ß, indoleamine 2,3-dioxygenase, and regulatory T cells. Furthermore, bioluminescent imaging with a granzyme B promoter-conjugated optical reporter also reflected improved cytotoxicity of antigen-specific CD8(+) T cells in tumor-bearing mice during treatment. These findings suggest that combination of multitargeting drugs, such as curcumin, with adoptive therapy may have potential for clinical application. In addition, using a granzyme B-specific imaging reporter to assess T-cell function may also be applied for the development and therapeutic evaluation of new immunotherapy in preclinical studies.


Subject(s)
Antineoplastic Agents/therapeutic use , CD8-Positive T-Lymphocytes/immunology , Curcumin/therapeutic use , Immunotherapy, Adoptive , T-Lymphocytes, Regulatory/immunology , T-Lymphocytes/immunology , Thymus Neoplasms/therapy , Animals , Blotting, Western , Combined Modality Therapy , Flow Cytometry , Fluorescent Antibody Technique , Granzymes/genetics , Immune Tolerance , Immunomodulation , Indoleamine-Pyrrole 2,3,-Dioxygenase/antagonists & inhibitors , Indoleamine-Pyrrole 2,3,-Dioxygenase/metabolism , Luminescent Measurements , Male , Mice , Mice, Inbred C57BL , Mice, Transgenic , Molecular Imaging , RNA, Messenger/genetics , T-Lymphocytes/drug effects , T-Lymphocytes/pathology , Thymus Neoplasms/drug therapy , Thymus Neoplasms/immunology , Transforming Growth Factor beta/antagonists & inhibitors , Transforming Growth Factor beta/metabolism , Tumor Cells, Cultured
7.
J Microbiol Immunol Infect ; 44(4): 265-73, 2011 Aug.
Article in English | MEDLINE | ID: mdl-21524954

ABSTRACT

BACKGROUND: Non-polio enteroviruses may cause different diseases, including herpangina, hand-foot-mouth disease (HFMD), meningitis, and nonspecific febrile illness; and cause epidemic outbreak annually. This study delineates the diversity of clinical presentations based on different serotypes and different groups [human enterovirus (HEV)-A and HEV-B] of enteroviruses (EVs) during the 2008 epidemic in National Taiwan University Hospital (NTUH). METHODS: We retrospectively identified patients younger than 18 years who had positive isolates of non-polio EV in throat swabs, rectal swabs, or cerebrospinal fluid, in NTUH from January 1 to December 31, 2008. For serotyping, immunofluorescence assay and polymerase chain reaction followed by viral structure protein-1 sequencing were applied. We analyzed and compared their clinical features among different serotypes and different groups of EVs. RESULTS: Among 172 patients who were enrolled, 16 serotypes were identified. The major serotype in NTUH was EV71 (25.6%) followed by coxsackievirus A (CA)16 and coxsackievirus B (CB)4. EV71 manifested mostly as HFMD (89%) and was complicated with encephalomyelitis in three patients. Serotypes of HFMD included EV71 (70%), CA16 (27%), CA4, and CA6. Serotypes of herpangina were heterogeneous, and the major serotype was CA2 (35.7%) followed by CB4 (23.8%). Aseptic meningitis was entirely caused by HEV-B and mostly infected by echovirus 30 (50%). Among children with EV-related respiratory tract infection, CB4 (32%) was dominant in upper respiratory tract infection, whereas echovirus 4 (71%) was the major cause of lower respiratory tract infection. Cases of HEV-A were significantly younger than the cases of HEV-B (p = 0.04). Multivariate analysis revealed that the most significant factor associated with hospitalization is HEV-B (odds ratio, 2.2; 95% confidence interval, 1.1-4.2; p = 0.02). CONCLUSIONS: At least 16 serotypes circulated in northern Taiwan in 2008. EV71 is the predominant strain in this outbreak. All patients with HFMD were infected by HEV-A, but HEV-B was associated with a higher rate of hospitalization and aseptic meningitis, which should be a cause of alert regarding public health.


Subject(s)
Enterovirus Infections/epidemiology , Enterovirus Infections/virology , Enterovirus/classification , Adolescent , Chi-Square Distribution , Child , Child, Preschool , Enterovirus/genetics , Enterovirus/isolation & purification , Enterovirus Infections/diagnosis , Female , Fluorescent Antibody Technique , Hospitalization/statistics & numerical data , Hospitals, University/statistics & numerical data , Humans , Infant , Male , Multivariate Analysis , Phylogeny , Polymerase Chain Reaction , Retrospective Studies , Serotyping , Taiwan/epidemiology
8.
Nucleic Acids Res ; 38(22): 8061-71, 2010 Dec.
Article in English | MEDLINE | ID: mdl-20716519

ABSTRACT

Fibroblast growth factor 9 (FGF9) is an autocrine/paracrine growth factor that plays vital roles in many physiologic processes including embryonic development. Aberrant expression of FGF9 causes human diseases and thus it highlights the importance of controlling FGF9 expression; however, the mechanism responsible for regulation of FGF9 expression is largely unknown. Here, we show the crucial role of an AU-rich element (ARE) in FGF9 3'-untranslated region (UTR) on controlling FGF9 expression. Our data demonstrated that AUF1 binds to this ARE to regulate FGF9 mRNA stability. Overexpression of each isoform of AUF1 (p37, p40, p42 and p45) showed that only the p42 isoform reduced the steady-state FGF9 mRNA. Also, knockdown of p42(AUF1) prolonged the half-life of FGF9 mRNA. The induction of FGF9 mRNA in prostaglandin (PG) E(2)-treated human endometrial stromal cells was accompanied with declined cytoplasmic AUF1. Nevertheless, ablation of AUF1 led to sustained elevation of FGF9 expression in these cells. Our study demonstrated that p42(AUF1) regulates both steady-state and PGE(2)-induced FGF9 mRNA stability through ARE-mediated mRNA degradation. Since almost half of the FGF family members are ARE-containing genes, our findings also suggest that ARE-mediated mRNA decay is a common pathway to control FGFs expression, and it represents a novel RNA regulon to coordinate FGFs homeostasis in various physiological conditions.


Subject(s)
3' Untranslated Regions , Dinoprostone/pharmacology , Fibroblast Growth Factor 9/genetics , Heterogeneous-Nuclear Ribonucleoprotein D/metabolism , RNA, Messenger/metabolism , Adenine/analysis , Base Sequence , Binding Sites , HEK293 Cells , Heterogeneous Nuclear Ribonucleoprotein D0 , Heterogeneous-Nuclear Ribonucleoprotein D/antagonists & inhibitors , Heterogeneous-Nuclear Ribonucleoprotein D/genetics , Humans , Molecular Sequence Data , Protein Isoforms/metabolism , RNA Interference , RNA Stability , Uracil/analysis
9.
Hum Mutat ; 28(1): 98, 2007 Jan.
Article in English | MEDLINE | ID: mdl-17154280

ABSTRACT

Fibroblast growth factor 9 (FGF9) is a member of secreted polypeptide families and involved in many important biological processes, including implantation and morphogenesis during embryogenesis and adult life. Recently, Fgf9-knockout mice exhibited male-to-female sex reversal, demonstrating a novel function for FGF9 in testicular development. We hypothesized that FGF9 is involved in sex development at an early embryonic stage in humans. In this study, we systematically screened sequences of the FGF9 gene in 21 XY females and 72 XX females and XY males to examine whether sequence variants of the FGF9 gene play a pathophysiological role on human gonadal dysgenesis. No mutation was identified, but a single nucleotide variant and two microsatellites were found. The allelic distribution of polymorphic microsatellite in the 3'-UTR of FGF9 between patients and controls was slightly different with Bonferroni correction (P=0.06). We further applied reporter gene system and quantitative RT-PCR to study the function of this microsatellite motif and results demonstrated that the (TG)(n) motif modulated gene expression at both pre- and post-transcriptional levels. The (TG)(14) allele, which showed a potential association with male-to-female sex reversal (odds ratio=6.08, 95% confidence interval=1.39-26.63), displayed the strongest promoter activity and longest mRNA stability. These data demonstrated that 3'-UTR microsatellite of the FGF9 is a functional polymorphism that plays dual roles in regulating FGF9 expression. Although our preliminary result suggested a possible association between FGF9 and human gonadal dysgenesis, the major limitation of small dataset in this study points out the requirement for further investigation.


Subject(s)
3' Untranslated Regions/genetics , Fibroblast Growth Factor 9/genetics , Fibroblast Growth Factor 9/metabolism , Microsatellite Repeats/physiology , Adolescent , Adult , Cells, Cultured , Child , Child, Preschool , DNA Mutational Analysis , DNA-Binding Proteins/genetics , Disorders of Sex Development/genetics , Female , Gene Expression Regulation , Gene Frequency , Genetic Variation , High Mobility Group Proteins/genetics , Humans , Luciferases/metabolism , Male , Promoter Regions, Genetic , SOXB1 Transcription Factors , Transfection
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