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1.
Ecol Lett ; 25(2): 483-497, 2022 Feb.
Article in English | MEDLINE | ID: mdl-34935272

ABSTRACT

Emerging infectious diseases have resulted in severe population declines across diverse taxa. In some instances, despite attributes associated with high extinction risk, disease emergence and host declines are followed by host stabilisation for unknown reasons. While host, pathogen, and the environment are recognised as important factors that interact to determine host-pathogen coexistence, they are often considered independently. Here, we use a translocation experiment to disentangle the role of host traits and environmental conditions in driving the persistence of remnant bat populations a decade after they declined 70-99% due to white-nose syndrome and subsequently stabilised. While survival was significantly higher than during the initial epidemic within all sites, protection from severe disease only existed within a narrow environmental space, suggesting host traits conducive to surviving disease are highly environmentally dependent. Ultimately, population persistence following pathogen invasion is the product of host-pathogen interactions that vary across a patchwork of environments.


Subject(s)
Ascomycota , Chiroptera , Mycoses , Animals , Ascomycota/pathogenicity , Chiroptera/microbiology , Host-Pathogen Interactions , Mycoses/virology , Nose/microbiology
2.
Pol J Microbiol ; 70(3): 395-400, 2021 Sep.
Article in English | MEDLINE | ID: mdl-34584533

ABSTRACT

Opportunistic fungal infections increase morbidity and mortality in COVID-19 patients monitored in intensive care units (ICU). As patients' hospitalization days in the ICU and intubation period increase, opportunistic infections also increase, which prolongs hospital stay days and elevates costs. The study aimed to describe the profile of fungal infections and identify the risk factors associated with mortality in COVID-19 intensive care patients. The records of 627 patients hospitalized in ICU with the diagnosis of COVID-19 were investigated from electronic health records and hospitalization files. The demographic characteristics (age, gender), the number of ICU hospitalization days and mortality rates, APACHE II scores, accompanying diseases, antibiotic-steroid treatments taken during hospitalization, and microbiological results (blood, urine, tracheal aspirate samples) of the patients were recorded. Opportunistic fungal infection was detected in 32 patients (5.10%) of 627 patients monitored in ICU with a COVID-19 diagnosis. The average APACHE II score of the patients was 28 ± 6. While 25 of the patients (78.12%) died, seven (21.87%) were discharged from the ICU. Candida parapsilosis (43.7%) was the opportunistic fungal agent isolated from most blood samples taken from COVID-19 positive patients. The mortality rate of COVID-19 positive patients with candidemia was 80%. While two out of the three patients (66.6%) for whom fungi were grown from their tracheal aspirate died, one patient (33.3%) was transferred to the ward. Opportunistic fungal infections increase the mortality rate of COVID-19-positive patients. In addition to the risk factors that we cannot change, invasive procedures should be avoided, constant blood sugar regulation should be applied, and unnecessary antibiotics use should be avoided.


Subject(s)
COVID-19/complications , COVID-19/microbiology , Fungi/pathogenicity , Intensive Care Units/statistics & numerical data , Mycoses/etiology , Mycoses/mortality , Opportunistic Infections/etiology , Aged , Aged, 80 and over , Cross Infection , Female , Fungi/classification , Fungi/isolation & purification , Humans , Length of Stay , Male , Middle Aged , Mycoses/blood , Mycoses/virology , Opportunistic Infections/blood , Opportunistic Infections/virology , Risk Factors
3.
Microbes Infect ; 23(4-5): 104806, 2021.
Article in English | MEDLINE | ID: mdl-33684520

ABSTRACT

This study aimed to investigate the frequency and characteristics of respiratory co-infections in COVID-19 patients in the intensive care unit (ICU). In this retrospective observational study, pathogens responsible for potential co-infections were detected by the bacterial culture, real-time polymerase chain reaction (RT-PCR), or serological fungal antigen tests. Demographic and clinical characteristics, as well as microbial results, were analyzed. Bacterial culture identified 56 (58.3%) positive samples for respiratory pathogens, with the most common bacteria being Burkholderia cepacia (18, 18.8%). RT-PCR detected 38 (76.0%) and 58 (87.9%) positive results in the severe and critical groups, respectively. Most common pathogens detected were Stenotrophomonas maltophilia (28.0%) and Pseudomonas aeruginosa (28.0%) in the severe group and S. maltophilia (45.5%) in the critical group. P. aeruginosa was detected more during the early stage after ICU admission. Acinetobacter baumannii and Staphylococcus aureus were more frequently identified during late ICU admission. Fungal serum antigens were more frequently positive in the critical group than in the severe group, and the positive rate of fungal serum antigens frequency increased with prolonged ICU stay. A high frequency of respiratory co-infections presented in ICU COVID-19 patients. Careful examinations and necessary tests should be performed to exclude these co-infections.


Subject(s)
Bacterial Infections/epidemiology , COVID-19/epidemiology , Coinfection/epidemiology , Mycoses/epidemiology , Adult , Aged , Aged, 80 and over , Bacterial Infections/virology , COVID-19/microbiology , China/epidemiology , Coinfection/microbiology , Coinfection/virology , Female , Humans , Intensive Care Units , Male , Middle Aged , Mycoses/virology , Respiratory Tract Infections/epidemiology
4.
Emerg Microbes Infect ; 9(1): 1958-1964, 2020 Dec.
Article in English | MEDLINE | ID: mdl-32815458

ABSTRACT

Objectives Severe or critical COVID-19 is associated with intensive care unit admission, increased secondary infection rate, and would lead to significant worsened prognosis. Risks and characteristics relating to secondary infections in severe COVID-19 have not been described. Methods Severe and critical COVID-19 patients from Shanghai were included. We collected lower respiratory, urine, catheters, and blood samples according to clinical necessity and culture and mNGS were performed. Clinical and laboratory data were archived. Results We found 57.89% (22/38) patients developed secondary infections. The patient receiving invasive mechanical ventilation or in critical state has a higher chance of secondary infections (P<0.0001). The most common infections were respiratory, blood-stream and urinary infections, and in respiratory infections, the most detected pathogens were gram-negative bacteria (26, 50.00%), following by gram-positive bacteria (14, 26.92%), virus (6, 11.54%), fungi (4, 7.69%), and others (2, 3.85%). Respiratory Infection rate post high flow, tracheal intubation, and tracheotomy were 12.90% (4/31), 30.43% (7/23), and 92.31% (12/13) respectively. Secondary infections would lead to lower discharge rate and higher mortality rate. Conclusion Our study originally illustrated secondary infection proportion in severe and critical COVID-19 patients. Culture accompanied with metagenomics sequencing increased pathogen diagnostic rate. Secondary infections risks increased after receiving invasive respiratory ventilations and intravascular devices, and would lead to a lower discharge rate and a higher mortality rate.


Subject(s)
Bacteremia/pathology , Bacterial Infections/pathology , Coronavirus Infections/pathology , Fungemia/pathology , Mycoses/pathology , Opportunistic Infections/pathology , Pneumonia, Viral/pathology , Respiratory Tract Infections/pathology , Urinary Tract Infections/pathology , Aged , Bacteremia/microbiology , Bacteremia/mortality , Bacteremia/virology , Bacterial Infections/microbiology , Bacterial Infections/mortality , Bacterial Infections/virology , Betacoronavirus/pathogenicity , COVID-19 , Coronavirus Infections/microbiology , Coronavirus Infections/mortality , Coronavirus Infections/virology , Critical Illness , Female , Fungemia/microbiology , Fungemia/mortality , Fungemia/virology , Fungi/pathogenicity , Gram-Negative Bacteria/pathogenicity , Gram-Positive Bacteria/pathogenicity , Humans , Intensive Care Units , Lung/microbiology , Lung/pathology , Lung/virology , Male , Middle Aged , Mycoses/microbiology , Mycoses/mortality , Mycoses/virology , Opportunistic Infections/microbiology , Opportunistic Infections/mortality , Opportunistic Infections/virology , Pandemics , Pneumonia, Viral/microbiology , Pneumonia, Viral/mortality , Pneumonia, Viral/virology , Respiration, Artificial/adverse effects , Respiratory Tract Infections/microbiology , Respiratory Tract Infections/mortality , Respiratory Tract Infections/virology , Retrospective Studies , Risk , SARS-CoV-2 , Severity of Illness Index , Survival Analysis , Urinary Tract Infections/microbiology , Urinary Tract Infections/mortality , Urinary Tract Infections/virology
5.
Appl Microbiol Biotechnol ; 104(18): 7777-7785, 2020 Sep.
Article in English | MEDLINE | ID: mdl-32780290

ABSTRACT

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), a novel ß-coronavirus, is the main pathogenic agent of the rapidly spreading pneumonia called coronavirus disease 2019 (COVID-19). SARS-CoV-2 infects much more people, especially the elder population, around the world than other coronavirus, such as SARS-CoV and MERS-CoV, which is challenging current global public health system. Beyond the pathogenesis of SARS-CoV-2, microbial coinfection plays an important role in the occurrence and development of SARS-CoV-2 infection by raising the difficulties of diagnosis, treatment, prognosis of COVID-19, and even increasing the disease symptom and mortality. We summarize the coinfection of virus, bacteria and fungi with SARS-CoV-2, their effects on COVID-19, the reasons of coinfection, and the diagnosis to emphasize the importance of microbial coinfection in COVID-19. KEY POINTS: • Microbial coinfection is a nonnegligible factor in COVID-19. • Microbial coinfection exacerbates the processes of the occurrence, development and prognosis of COVID-19, and the difficulties of clinical diagnosis and treatment. • Different virus, bacteria, and fungi contributed to the coinfection with SARS-CoV-2.


Subject(s)
Bacterial Infections/epidemiology , Coronavirus Infections/epidemiology , Cytokine Release Syndrome/epidemiology , Lymphopenia/epidemiology , Mycoses/epidemiology , Pandemics , Pneumonia, Viral/epidemiology , Virus Diseases/epidemiology , Anti-Bacterial Agents/therapeutic use , Antiviral Agents/therapeutic use , Bacterial Infections/drug therapy , Bacterial Infections/microbiology , Bacterial Infections/virology , Betacoronavirus/drug effects , Betacoronavirus/immunology , Betacoronavirus/pathogenicity , COVID-19 , Coinfection , Coronavirus Infections/drug therapy , Coronavirus Infections/microbiology , Coronavirus Infections/virology , Cytokine Release Syndrome/drug therapy , Cytokine Release Syndrome/microbiology , Cytokine Release Syndrome/virology , Cytokines/biosynthesis , Disease Progression , Host-Pathogen Interactions/immunology , Humans , Immunity, Innate/drug effects , Lymphocytes/microbiology , Lymphocytes/virology , Lymphopenia/drug therapy , Lymphopenia/microbiology , Lymphopenia/virology , Mycoses/drug therapy , Mycoses/microbiology , Mycoses/virology , Pneumonia, Viral/drug therapy , Pneumonia, Viral/microbiology , Pneumonia, Viral/virology , SARS-CoV-2 , Virus Diseases/drug therapy , Virus Diseases/microbiology , Virus Diseases/virology
6.
Clin Microbiol Infect ; 26(10): 1395-1399, 2020 Oct.
Article in English | MEDLINE | ID: mdl-32603803

ABSTRACT

OBJECTIVES: To investigate the incidence of bacterial and fungal coinfection of hospitalized patients with confirmed severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in this retrospective observational study across two London hospitals during the first UK wave of coronavirus disease 2019 (COVID-19). METHODS: A retrospective case series of hospitalized patients with confirmed SARS-CoV-2 by PCR was analysed across two acute NHS hospitals (20 February-20 April 2020; each isolate reviewed independently in parallel). This was contrasted to a control group of influenza-positive patients admitted during the 2019-2020 flu season. Patient demographics, microbiology and clinical outcomes were analysed. RESULTS: A total of 836 patients with confirmed SARS-CoV-2 were included; 27 (3.2%) of 836 had early confirmed bacterial isolates identified (0-5 days after admission), rising to 51 (6.1%) of 836 throughout admission. Blood cultures, respiratory samples, pneumococcal or Legionella urinary antigens and respiratory viral PCR panels were obtained from 643 (77%), 110 (13%), 249 (30%), 246 (29%) and 250 (30%) COVID-19 patients, respectively. A positive blood culture was identified in 60 patients (7.1%), of which 39 were classified as contaminants. Bacteraemia resulting from respiratory infection was confirmed in two cases (one each community-acquired Klebsiella pneumoniae and ventilator-associated Enterobacter cloacae). Line-related bacteraemia was identified in six patients (three Candida, two Enterococcus spp. and one Pseudomonas aeruginosa). All other community-acquired bacteraemias (n = 16) were attributed to nonrespiratory infection. Zero concomitant pneumococcal, Legionella or influenza infection was detected. A low yield of positive respiratory cultures was identified; Staphylococcus aureus was the most common respiratory pathogen isolated in community-acquired coinfection (4/24; 16.7%), with pseudomonas and yeast identified in late-onset infection. Invasive fungal infections (n = 3) were attributed to line-related infections. Comparable rates of positive coinfection were identified in the control group of confirmed influenza infection; clinically relevant bacteraemias (2/141; 1.4%), respiratory cultures (10/38; 26.3%) and pneumococcal-positive antigens (1/19; 5.3%) were low. CONCLUSIONS: We found a low frequency of bacterial coinfection in early COVID-19 hospital presentation, and no evidence of concomitant fungal infection, at least in the early phase of COVID-19.


Subject(s)
Bacterial Infections/epidemiology , Betacoronavirus/pathogenicity , Coronavirus Infections/epidemiology , Influenza, Human/epidemiology , Mycoses/epidemiology , Pandemics , Pneumonia, Viral/epidemiology , Respiratory Tract Infections/epidemiology , Age Factors , Aged , Aged, 80 and over , Bacterial Infections/diagnosis , Bacterial Infections/microbiology , Bacterial Infections/virology , COVID-19 , Coinfection , Community-Acquired Infections , Coronavirus Infections/diagnosis , Coronavirus Infections/microbiology , Coronavirus Infections/virology , Female , Hospitalization , Humans , Influenza, Human/diagnosis , Influenza, Human/microbiology , Influenza, Human/virology , Male , Middle Aged , Mycoses/diagnosis , Mycoses/microbiology , Mycoses/virology , Pneumonia, Viral/diagnosis , Pneumonia, Viral/microbiology , Pneumonia, Viral/virology , Respiratory Tract Infections/diagnosis , Respiratory Tract Infections/microbiology , Respiratory Tract Infections/virology , Retrospective Studies , SARS-CoV-2 , Severity of Illness Index , United Kingdom/epidemiology
7.
AIDS Res Ther ; 17(1): 26, 2020 05 26.
Article in English | MEDLINE | ID: mdl-32456686

ABSTRACT

BACKGROUND: The clinical and laboratory characteristics of AIDS-associated Talaromyces marneffei infection, a rare but a fatal mycosis disease of the central nervous system, remain unclear. CASE PRESENTATION: Herein, we conducted a retrospective study of ten AIDS patients with cerebrospinal fluid culture-confirmed central nervous system infection caused by Talaromyces marneffei. All 10 patients were promptly treated with antifungal treatment for a prolonged duration and early antiviral therapy (ART). Among them, seven patients were farmers. Nine patients were discharged after full recovery, while one patient died during hospitalization, resulting in a mortality rate of 10%. All patients initially presented symptoms and signs of an increase in intracranial pressure, mainly manifesting as headache, dizziness, vomiting, fever, decreased muscle strength, diplopia or even altered consciousness with seizures in severe patients. Nine patients (90%) showed lateral ventricle dilatation or intracranial infectious lesions on brain CT. Cerebrospinal fluid findings included elevated intracranial pressure, increased leukocyte count, low glucose, low chloride and high cerebrospinal fluid protein. The median CD4+ T count of patients was 104 cells/µL (IQR, 36-224 cells/µL) at the onset of the disease. The CD4+ T cell counts of three patients who eventually died were significantly lower (W = 6.00, p = 0.020) than those of the patients who survived. CONCLUSIONS: The common clinical symptoms of T. marneffei central nervous system infection are associated with high intracranial pressure and intracranial infectious lesions. Earlier recognition and diagnosis and a prolonged course of amphotericin B treatment followed by itraconazole combined with early ART might reduce the mortality rate.


Subject(s)
AIDS-Related Opportunistic Infections/microbiology , Central Nervous System Infections/microbiology , HIV Infections/complications , Mycoses/cerebrospinal fluid , Mycoses/virology , Talaromyces/pathogenicity , AIDS-Related Opportunistic Infections/epidemiology , Adult , Antifungal Agents/therapeutic use , Central Nervous System Infections/etiology , China/epidemiology , Female , HIV Infections/epidemiology , HIV Infections/microbiology , Humans , Male , Middle Aged , Mycoses/drug therapy , Mycoses/epidemiology , Retrospective Studies
8.
J Infect ; 81(2): 266-275, 2020 08.
Article in English | MEDLINE | ID: mdl-32473235

ABSTRACT

OBJECTIVES: In previous influenza pandemics, bacterial co-infections have been a major cause of mortality. We aimed to evaluate the burden of co-infections in patients with COVID-19. METHODS: We systematically searched Embase, Medline, Cochrane Library, LILACS and CINAHL for eligible studies published from 1 January 2020 to 17 April 2020. We included patients of all ages, in all settings. The main outcome was the proportion of patients with a bacterial, fungal or viral co-infection. . RESULTS: Thirty studies including 3834 patients were included. Overall, 7% of hospitalised COVID-19 patients had a bacterial co-infection (95% CI 3-12%, n=2183, I2=92·2%). A higher proportion of ICU patients had bacterial co-infections than patients in mixed ward/ICU settings (14%, 95% CI 5-26, I2=74·7% versus 4%, 95% CI 1-9, I2= 91·7%). The commonest bacteria were Mycoplasma pneumonia, Pseudomonas aeruginosa and Haemophilus influenzae. The pooled proportion with a viral co-infection was 3% (95% CI 1-6, n=1014, I2=62·3%), with Respiratory Syncytial Virus and influenza A the commonest. Three studies reported fungal co-infections. CONCLUSIONS: A low proportion of COVID-19 patients have a bacterial co-infection; less than in previous influenza pandemics. These findings do not support the routine use of antibiotics in the management of confirmed COVID-19 infection.


Subject(s)
Bacterial Infections/virology , Coinfection/microbiology , Coinfection/virology , Coronavirus Infections/virology , Pneumonia, Viral/virology , Bacterial Infections/complications , Bacterial Infections/epidemiology , Betacoronavirus , COVID-19 , Coinfection/epidemiology , Coronavirus Infections/complications , Coronavirus Infections/epidemiology , Humans , Mycoses/complications , Mycoses/epidemiology , Mycoses/virology , Pandemics , Pneumonia, Viral/complications , Pneumonia, Viral/epidemiology , SARS-CoV-2 , Virus Diseases/complications , Virus Diseases/epidemiology , Virus Diseases/microbiology
9.
Int J Mol Sci ; 21(5)2020 Mar 06.
Article in English | MEDLINE | ID: mdl-32155734

ABSTRACT

Wheat (Triticum aestivum L.) is an important staple crop. Rhizoctonia cerealis is the causal agent of diseases that are devastating to cereal crops, including wheat. Xylanases play an important role in pathogenic infection, but little is known about xylanases in R. cerealis. Herein, we identified nine xylanase-encoding genes from the R. cerealis genome, named RcXYN1-RcXYN9, examined their expression patterns, and investigated the pathogenicity role of RcXYN1. RcXYN1-RcXYN9 proteins contain two conserved glutamate residues within the active motif in the glycoside hydrolase 10 (GH10) domain. Of them, RcXYN1-RcXYN4 are predicted to be secreted proteins. RcXYN1-RcXYN9 displayed different expression patterns during the infection process of wheat, and RcXYN1, RcXYN2, RcXYN5, and RcXYN9 were expressed highly across all the tested inoculation points. Functional dissection indicated that the RcXYN1 protein was able to induce necrosis/cell-death and H2O2 generation when infiltrated into wheat and Nicotiana benthamiana leaves. Furthermore, application of RcXYN1 protein followed by R. cerealis led to significantly higher levels of the disease in wheat leaves than application of the fungus alone. These results demonstrate that RcXYN1 acts as a pathogenicity factor during R. cerealis infection in wheat. This is the first investigation of xylanase genes in R. cerealis, providing novel insights into the pathogenesis mechanisms of R. cerealis.


Subject(s)
Disease Resistance/genetics , Endo-1,4-beta Xylanases/metabolism , Plant Diseases/genetics , Rhizoctonia/enzymology , Rhizoctonia/genetics , Triticum/virology , Viral Proteins/genetics , Endo-1,4-beta Xylanases/genetics , Gene Expression Regulation, Viral , Genome, Viral , Host-Pathogen Interactions , Mycoses/virology , Plant Diseases/virology , Viral Proteins/metabolism
10.
Arq. Inst. Biol ; 86: e0162019, 2019. graf
Article in English | LILACS, VETINDEX | ID: biblio-1046021

ABSTRACT

The Lonchaeidae family comprises species that are considered of major economic importance due of their damage in several crops. In sweet passion fruit (Passiflora ligularis Juss), these flies cause high infestation in flower buds and fruits, however only a few basic studies about the species associated with the damage are available. Samples of flower buds and fruits were taken and McPhail trap baits with Torula yeast were placed in sweet passion fruit orchards in Oxapampa (Pasco, Peru) in 2015­2016. In addition, other hosts were collected in this period. We found Dasiops inedulis Steykal infesting the flower buds, while Dasiops frieseni Norrbom & McAlpine infesting sweet passion fruits. Moreover, other Lonchaeidae-hosts interactions are related. Through Torula yeast baits, 14 species of lance flies were detected and high numbers of D. inedulis specimens were captured.(AU)


A família Lonchaeidae inclui espécies que são consideradas de grande importância econômica devido aos seus danos em diferentes cultivos. No maracujá-doce (Passiflora ligularis Juss), essas moscas causam altas infestações em botões florais e frutos, tendo ainda poucos estudos sobre as espécies associadas aos danos. Amostragem de botões florais e frutos foram realizadas e armadilhas McPhail com levedura de Torula foram colocadas em fazendas de maracujá em Oxapampa (Pasco, Peru) durante os anos de 2015 e 2016. Além disso, outros hospedeiros foram coletados nesse período. Nós encontramos Dasiops inedulis Steykal infestando botões florais e Dasiops frieseni Norrbom & McAlpine em frutos de maracujá-doce. Além disso, outras interações Lonchaeidae-hospedeiro são relacionadas. Mediante iscas de levedura de Torula, 14 espécies de Lonchaeidae foram detectadas e altos números de espécimes de D. inedulis foram capturados.(AU)


Subject(s)
Passiflora , Diptera , Peru , Mycoses/virology
11.
Microb Pathog ; 105: 321-325, 2017 Apr.
Article in English | MEDLINE | ID: mdl-28104384

ABSTRACT

Penicillium marneffei (P. marneffei) causes systemic opportunistic infections in immunocompromised individuals, particularly in those infected with human immunodeficiency virus (HIV), and more rarely in HIV-negative patients. We retrospectively analyzed the cases of 15 patients infected with P. marneffei. The patients were divided into two groups: HIV-negative (n = 4) and HIV-positive (n = 11). Of the cases studied, three (75%) of the HIV-negative and six (55%) of the HIV-positive group had an accompanying lung infection. The ratio of CD4+/CD8+ was 1.2 (SD = 0.99) in the HIV-negative group and 0.10 (SD = 0.095) in the HIV-positive patients. A series of laboratory examinations were performed and bone marrow smears were observed after staining. P. marneffei is a disseminated fungal infection associated with severe disease symptoms and high mortality rates. Our findings indicate that timely diagnosis and treatment by clinicians is crucial for preventing the spread of localized infections into systemic infections, thereby improving the prognosis of patients.


Subject(s)
HIV Infections/microbiology , Mycoses/microbiology , Opportunistic Infections/microbiology , Penicillium/isolation & purification , Adult , Antifungal Agents/therapeutic use , China/epidemiology , Female , HIV Infections/epidemiology , HIV Seronegativity , HIV Seropositivity , Humans , Male , Middle Aged , Mycoses/epidemiology , Mycoses/virology , Opportunistic Infections/virology , Pneumonia/epidemiology , Pneumonia/microbiology , Pneumonia/virology , Retrospective Studies
12.
Exp Suppl ; 107: 287-323, 2016.
Article in English | MEDLINE | ID: mdl-27812985

ABSTRACT

During host-pathogen interactions, a complex web of events is crucial for the outcome of infection. Pathogen recognition triggers powerful cellular signaling events that is translated into the induction and maintenance of innate and adaptive host immunity against infection. In opposition, pathogens employ active mechanisms to manipulate host cell regulatory pathways toward their proliferation and survival. Among these, subversion of host cell energy metabolism by pathogens is currently recognized to play an important role in microbial growth and persistence. Extensive studies have documented the role of AMP-activated protein kinase (AMPK) signaling, a central cellular hub involved in the regulation of energy homeostasis, in host-pathogen interactions. Here, we highlight the most recent advances detailing how pathogens hijack cellular metabolism by suppressing or increasing the activity of the host energy sensor AMPK. We also address the role of lower eukaryote AMPK orthologues in the adaptive process to the host microenvironment and their contribution for pathogen survival, differentiation, and growth. Finally, we review the effects of pharmacological or genetic AMPK modulation on pathogen growth and persistence.


Subject(s)
AMP-Activated Protein Kinases/genetics , Bacteria/metabolism , Fungi/enzymology , Host-Pathogen Interactions/genetics , Viruses/metabolism , AMP-Activated Protein Kinases/antagonists & inhibitors , AMP-Activated Protein Kinases/immunology , Anti-Infective Agents/therapeutic use , Autophagy/drug effects , Autophagy/immunology , Bacteria/drug effects , Bacteria/genetics , Bacterial Infections/drug therapy , Bacterial Infections/enzymology , Bacterial Infections/genetics , Bacterial Infections/virology , Fungi/drug effects , Fungi/genetics , Gene Expression Regulation , Host-Pathogen Interactions/drug effects , Humans , Immunity, Innate/drug effects , Molecular Targeted Therapy , Mycoses/drug therapy , Mycoses/enzymology , Mycoses/genetics , Mycoses/virology , Protein Serine-Threonine Kinases/antagonists & inhibitors , Protein Serine-Threonine Kinases/genetics , Protein Serine-Threonine Kinases/immunology , Protein Subunits/antagonists & inhibitors , Protein Subunits/genetics , Protein Subunits/immunology , Signal Transduction , Virus Diseases/drug therapy , Virus Diseases/enzymology , Virus Diseases/genetics , Virus Diseases/virology , Viruses/drug effects , Viruses/genetics
13.
Dis Aquat Organ ; 111(3): 229-38, 2014 Oct 16.
Article in English | MEDLINE | ID: mdl-25320035

ABSTRACT

A series of fungal cases in hatchery-reared juvenile and young adult Siberian sturgeon Acipenser baerii and white sturgeon A. transmontanus occurred at production facilities in Florida and California, USA, respectively. Affected fish exhibited abnormal orientation and/or buoyancy, emaciation, coelomic distension, exophthalmos, cutaneous erythema, and ulcerative skin and eye lesions. Necropsies revealed haemorrhage throughout the coelom, serosanguinous coelomic effusion and organomegaly with nodular or cystic lesions in multiple organs. Fungal hyphae were observed in 27 fish (24 A. baerii and 3 A. transmontanus) via microscopic examination of tissue wet mounts and on slides prepared from colonies grown on culture media. Histopathological examination of these infected tissues revealed extensive infiltration by melanised fungal hyphae that were recovered in culture. Phenotypic characteristics and sequencing of the fungal isolates with the use of the internal transcribed spacer region and 28S rRNA gene confirmed the aetiological agent as Veronaea botryosa. To our knowledge, this is the first documentation of V. botryosa infection in fish, although melanised fungi of the closely related genus Exophiala are well-known pathogens of freshwater and marine fishes.


Subject(s)
Ascomycota/isolation & purification , Fish Diseases/microbiology , Mycoses/veterinary , Animals , Ascomycota/genetics , DNA, Fungal/genetics , Fish Diseases/pathology , Fishes , Mycoses/pathology , Mycoses/virology , Polymerase Chain Reaction/veterinary
14.
Clin Infect Dis ; 54(2): e8-e19, 2012 Jan 15.
Article in English | MEDLINE | ID: mdl-22065867

ABSTRACT

BACKGROUND: Penicillium marneffei infection is indigenous to Southeast Asia. Majority of penicilliosis occurs in patients with AIDS, and less commonly with secondary immunodeficiencies. Penicilliosis is rare in otherwise healthy persons, but information on their immunological status is often lacking. METHODS: From 1996 to 2009, we diagnosed penicilliosis in 5 children. Their clinical features, immunological findings, and genetic studies were analyzed. A systematic review of the English and Chinese literature was performed. Case reports/series on patients <18 years with penicilliosis were included, and patients stated to be human immunodeficiency virus (HIV)-positive excluded. RESULTS: All of our 5 patients were HIV negative. Presentations included fungemia (n = 2), multifocal lymphadenopathy (n = 2), and necrotizing pneumonia (n = 1). Four patients had recurrent mucocutaneous candidiasis. Hyperimmunoglobin E syndrome was diagnosed in 1 patient, while another had functional defect in interleukin-12/interferon-γ axis. Three patients were lymphopenic with low natural killer cell counts, but a specific immune defect was not identified. Systematic review of 509 reports on human penicilliosis identified 32 patients aged 3 months to 16 years with no known HIV infection. Twenty-four patients (75%) had disseminated disease, and 55% died of penicilliosis. Eight patients had primary immunodeficiencies or blood disorders, while 4 others had abnormal immune functions. Immune evaluations of the remaining patients were unstated. CONCLUSION: Penicilliosis is a severe disease causing high mortality in children. As an AIDS-defining illness, penicilliosis should be regarded as an indicator for underlying immunodeficiency in HIV-negative individuals. Immunological investigations should be performed, especially in those with recurrent infections. Multicentered collaborative studies are needed to collect information on long-term prognosis and define immune defects underlying penicilliosis.


Subject(s)
AIDS-Related Opportunistic Infections/microbiology , HIV Infections/microbiology , Mycoses/virology , Penicillium/isolation & purification , AIDS-Related Opportunistic Infections/immunology , Adolescent , Child , Child, Preschool , Fatal Outcome , Female , HIV Infections/immunology , Humans , Immunocompetence , Immunocompromised Host , Lymphatic Diseases/microbiology , Lymphatic Diseases/virology , Mycoses/immunology , Pneumonia/microbiology
15.
Avian Pathol ; 38(4): 311-6, 2009 Aug.
Article in English | MEDLINE | ID: mdl-19937516

ABSTRACT

Mortality in excess of 65% occurred in a flock of 450 canaries (Serinus canaria). Clinical signs in the canaries included severe respiratory distress, loss of feathers and/or scaly skin on the head, neck and back, anorexia, loss of weight and fluffed-up appearance of several days duration before death. Gross pathology in most of the canaries included thickened eye lids and small scab-like nodules on the skin of the head and neck, enlarged thymus, mild to severe consolidation of lungs and exudate in the sinuses and trachea. A few birds also had thickened air sacs and enlarged and pale spleens. Microscopically unusual lesions included severe epithelial proliferation and hypertrophy and mononuclear inflammatory cells containing eosinophilic intracytoplasmic inclusion bodies of poxvirus in the thymus, bursa of Fabricius, spleen, bone marrow, air sac, peritoneum, external and middle ears, and lachrymal gland. Similar inclusion bodies associated with inflammation were also seen in the epidermis, dermis, feather follicles, conjunctivae, sinuses, turbinates, choana, oral mucosa including tongue, oesophagus, larynx, trachea, syrinx and bronchi and parabronchi of lungs. Some of the birds also had concurrent bacterial, mycotic and polyomavirus infections. Poxvirus was isolated from lungs and skin in chicken embryo liver cells and confirmed as avian poxvirus by polymerase chain reaction.


Subject(s)
Avipoxvirus/pathogenicity , Bird Diseases/virology , Canaries , Poxviridae Infections/veterinary , Animal Husbandry , Animals , Bacterial Infections/complications , Bacterial Infections/virology , Bird Diseases/mortality , Embryo, Nonmammalian/virology , Inclusion Bodies, Viral/pathology , Inclusion Bodies, Viral/virology , Inflammation/pathology , Inflammation/virology , Liver/embryology , Liver/virology , Lymphoid Tissue/pathology , Lymphoid Tissue/virology , Mycoses/complications , Mycoses/virology , Polyomavirus Infections/complications , Polyomavirus Infections/virology , Poxviridae Infections/complications , Poxviridae Infections/mortality , Poxviridae Infections/virology , Respiratory System/pathology , Respiratory System/virology , Skin/pathology , Skin/virology
17.
Am J Trop Med Hyg ; 77(2): 350-3, 2007 Aug.
Article in English | MEDLINE | ID: mdl-17690411

ABSTRACT

The objective of this study was to evaluate the triazole anti-fungal agent, voriconazole, as therapy for systemic Penicillium marneffei infections in patients with advanced HIV infection. Patients with systemic P. marneffei infection were enrolled into a study of voriconazole for the treatment of less common, emerging, or refractory fungal infections. Patients were eligible for inclusion in the study on the basis that no anti-fungal agents have received regulatory approval specifically for P. marneffei infections. Patients were treated in the hospital setting with intravenous voriconazole (6 mg/kg every 12 hours on Day 1 and then 4 mg/kg every 12 hours for at least 3 days, after which patients could switch to oral therapy at 200 mg twice a day) or as outpatients with oral voriconazole (400 mg twice a day on Day 1 and then 200 mg twice a day) for a maximum of 12 weeks. Eleven patients received treatment with voriconazole. Two received short courses of intravenous therapy followed by the oral formulation; nine were treated with oral voriconazole only. At the end of therapy, eight of the nine evaluable patients had favorable response to therapy, based on mycological and clinical findings. There were no relapses of P. marneffei infection in the six patients who were seen at follow-up within 4 weeks of the end of therapy. Treatment with voriconazole was well tolerated, with no discontinuations caused by drug-related adverse events. The results of this study suggest that voriconazole is an effective, well-tolerated, and convenient option for the treatment of systemic infections with P. marneffei.


Subject(s)
AIDS-Related Opportunistic Infections/drug therapy , Acquired Immunodeficiency Syndrome/complications , Antifungal Agents/therapeutic use , Mycoses/complications , Mycoses/drug therapy , Penicillium/growth & development , Pyrimidines/therapeutic use , Triazoles/therapeutic use , AIDS-Related Opportunistic Infections/microbiology , Acquired Immunodeficiency Syndrome/microbiology , Adult , Female , Humans , Male , Mycoses/microbiology , Mycoses/virology , Voriconazole
20.
Am J Transplant ; 5(8): 2067-9, 2005 Aug.
Article in English | MEDLINE | ID: mdl-15996262

ABSTRACT

The immunosuppressive regimens that are used in solid organ transplantation are potent inhibitors of Th0 as well as Th1 and Th2 cell-mediated immune responses. This predisposes patients to disseminated cryptococcal infections. Mortality in such patients remains very high despite advances in anti-fungal chemotherapy. We describe a case of disseminated cryptococcal disease in a renal allograft recipient that failed to respond to prolonged treatment with several anti-fungal drugs. However, addition of the immuno-modulator, interferon-gamma, resulted in the formation of granulomas and the resolution of his disease within 4-6 weeks. As we cannot find a similar example of combination therapy for disseminated cryptococcal disease in the solid organ transplant literature, we propose that interferon-gamma could be used in synergy with anti-fungal drugs to cure disseminated cryptococcal infections in solid organ transplant patients.


Subject(s)
Antifungal Agents/therapeutic use , Antiviral Agents/therapeutic use , Cryptococcosis , Interferon-gamma/therapeutic use , Kidney Transplantation/adverse effects , Adult , Cryptococcosis/microbiology , Cryptococcosis/physiopathology , Drug Therapy, Combination , Humans , Male , Mycoses/physiopathology , Mycoses/virology , Transplantation, Homologous
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