New insights into innate immune control of systemic candidiasis

PubMed Central

Lionakis, Michail S.

2014-01-01

Systemic infection caused by Candida species is the fourth leading cause of nosocomial bloodstream infection in modern hospitals and carries high morbidity and mortality despite antifungal therapy. A recent surge of immunological studies in the mouse models of systemic candidiasis and the parallel discovery and phenotypic characterization of inherited genetic disorders in antifungal immune factors that are associated with enhanced susceptibility or resistance to the infection have provided new insights into the cellular and molecular basis of protective innate immune responses against Candida. In this review, the new developments in our understanding of how the mammalian immune system responds to systemic Candida challenge are synthesized and important future research directions are highlighted. PMID:25023483

Clinical correlates and outcomes in a group of Puerto Ricans with systemic lupus erythematosus hospitalized due to severe infections

PubMed Central

Jordán-González, Patricia; Shum, Lee Ming; González-Sepúlveda, Lorena

2018-01-01

Objective: Infections are a major cause of morbidity and mortality in systemic lupus erythematosus. Clinical outcomes of systemic lupus erythematosus patients hospitalized due to infections vary among different ethnic populations. Thus, we determined the outcomes and associated factors in a group of Hispanics from Puerto Rico with systemic lupus erythematosus admitted due to severe infections. Methods: Records of systemic lupus erythematosus patients admitted to the Adult University Hospital, San Juan, Puerto Rico, from January 2006 to December 2014 were examined. Demographic parameters, lupus manifestations, comorbidities, pharmacologic treatments, inpatient complications, length of stay, readmissions, and mortality were determined. Patients with and without infections were compared using bivariate and multivariate analyses. Results: A total of 204 admissions corresponding to 129 systemic lupus erythematosus patients were studied. The mean (standard deviation) age was 34.7 (11.6) years; 90% were women. The main causes for admission were lupus flare (45.1%), infection (44.0%), and initial presentation of systemic lupus erythematosus (6.4%). The most common infections were complicated urinary tract infections (47.0%) and soft tissue infections (42.0%). In the multivariate analysis, patients admitted with infections were more likely to have diabetes mellitus (odds ratio: 4.20, 95% confidence interval: 1.23–14.41), exposure to aspirin prior to hospitalization (odds ratio: 4.04, 95% confidence interval: 1.03–15.80), and higher mortality (odds ratio: 6.00, 95% confidence interval: 1.01–35.68) than those without infection. Conclusion: In this population of systemic lupus erythematosus patients, 44% of hospitalizations were due to severe infections. Patients with infections were more likely to have diabetes mellitus and higher mortality. Preventive and control measures of infection could be crucial to improve survival in these patients.

Clinical correlates and outcomes in a group of Puerto Ricans with systemic lupus erythematosus hospitalized due to severe infections.

PubMed

Jordán-González, Patricia; Shum, Lee Ming; González-Sepúlveda, Lorena; Vilá, Luis M

2018-01-01

Infections are a major cause of morbidity and mortality in systemic lupus erythematosus. Clinical outcomes of systemic lupus erythematosus patients hospitalized due to infections vary among different ethnic populations. Thus, we determined the outcomes and associated factors in a group of Hispanics from Puerto Rico with systemic lupus erythematosus admitted due to severe infections. Records of systemic lupus erythematosus patients admitted to the Adult University Hospital, San Juan, Puerto Rico, from January 2006 to December 2014 were examined. Demographic parameters, lupus manifestations, comorbidities, pharmacologic treatments, inpatient complications, length of stay, readmissions, and mortality were determined. Patients with and without infections were compared using bivariate and multivariate analyses. A total of 204 admissions corresponding to 129 systemic lupus erythematosus patients were studied. The mean (standard deviation) age was 34.7 (11.6) years; 90% were women. The main causes for admission were lupus flare (45.1%), infection (44.0%), and initial presentation of systemic lupus erythematosus (6.4%). The most common infections were complicated urinary tract infections (47.0%) and soft tissue infections (42.0%). In the multivariate analysis, patients admitted with infections were more likely to have diabetes mellitus (odds ratio: 4.20, 95% confidence interval: 1.23-14.41), exposure to aspirin prior to hospitalization (odds ratio: 4.04, 95% confidence interval: 1.03-15.80), and higher mortality (odds ratio: 6.00, 95% confidence interval: 1.01-35.68) than those without infection. In this population of systemic lupus erythematosus patients, 44% of hospitalizations were due to severe infections. Patients with infections were more likely to have diabetes mellitus and higher mortality. Preventive and control measures of infection could be crucial to improve survival in these patients.

Effects of invertebrate iridescent virus 6 in Phyllophaga vandinei and its potential as a biocontrol delivery system

USDA-ARS?s Scientific Manuscript database

Invertebrate iridescent virus 6 (IIV6) was determined to cause infection in Phyllophaga vandinei Smyth, through a range of modes of transmissions. This is the first evidence of IIV6 infection in P. vandinei, which caused both patent and sub-lethal covert infections in larvae and adults. Mortality r...

BK nephropathy in the native kidneys of patients with organ transplants: Clinical spectrum of BK infection

PubMed Central

Vigil, Darlene; Konstantinov, Nikifor K; Barry, Marc; Harford, Antonia M; Servilla, Karen S; Kim, Young Ho; Sun, Yijuan; Ganta, Kavitha; Tzamaloukas, Antonios H

2016-01-01

Nephropathy secondary to BK virus, a member of the Papoviridae family of viruses, has been recognized for some time as an important cause of allograft dysfunction in renal transplant recipients. In recent times, BK nephropathy (BKN) of the native kidneys has being increasingly recognized as a cause of chronic kidney disease in patients with solid organ transplants, bone marrow transplants and in patients with other clinical entities associated with immunosuppression. In such patients renal dysfunction is often attributed to other factors including nephrotoxicity of medications used to prevent rejection of the transplanted organs. Renal biopsy is required for the diagnosis of BKN. Quantitation of the BK viral load in blood and urine are surrogate diagnostic methods. The treatment of BKN is based on reduction of the immunosuppressive medications. Several compounds have shown antiviral activity, but have not consistently shown to have beneficial effects in BKN. In addition to BKN, BK viral infection can cause severe urinary bladder cystitis, ureteritis and urinary tract obstruction as well as manifestations in other organ systems including the central nervous system, the respiratory system, the gastrointestinal system and the hematopoietic system. BK viral infection has also been implicated in tumorigenesis. The spectrum of clinical manifestations from BK infection and infection from other members of the Papoviridae family is widening. Prevention and treatment of BK infection and infections from other Papovaviruses are subjects of intense research. PMID:27683628

Pseudomonas aeruginosa adapts its iron uptake strategies in function of the type of infections

PubMed Central

Cornelis, Pierre; Dingemans, Jozef

2013-01-01

Pseudomonas aeruginosa is a Gram-negative γ-Proteobacterium which is known for its capacity to colonize various niches, including some invertebrate and vertebrate hosts, making it one of the most frequent bacteria causing opportunistic infections. P. aeruginosa is able to cause acute as well as chronic infections and it uses different colonization and virulence factors to do so. Infections range from septicemia, urinary infections, burn wound colonization, and chronic colonization of the lungs of cystic fibrosis patients. Like the vast majority of organisms, P. aeruginosa needs iron to sustain growth. P. aeruginosa utilizes different strategies to take up iron, depending on the type of infection it causes. Two siderophores are produced by this bacterium, pyoverdine and pyochelin, characterized by high and low affinities for iron respectively. P. aeruginosa is also able to utilize different siderophores from other microorganisms (siderophore piracy). It can also take up heme from hemoproteins via two different systems. Under microaerobic or anaerobic conditions, P. aeruginosa is also able to take up ferrous iron via its Feo system using redox-cycling phenazines. Depending on the type of infection, P. aeruginosa can therefore adapt by switching from one iron uptake system to another as we will describe in this short review. PMID:24294593

Mycoplasmosis

USGS Publications Warehouse

Friend, M.

1999-01-01

Mycoplasmosis is caused by infection with a unique group of bacteria that lack cell walls but possess distinctive plasma membranes. Mycoplasma are also the smallest self-replicating life-forms, and they are responsible for a variety of diseases in humans, animals, insects, and plants. These bacteria can cause acute and chronic diseases in hosts that they infect, and they are also implicated with other microbes as causes of disease when the immune system of the host has become impaired through concurrent infection by other disease agents or through other processes. This chapter focuses on mycoplasmal infections of birds, the most significant of which are caused by Mycoplasma gallisepticum (MG), M. meleagridis (MM), and M. synoviae (MS). Only MG is of known importance for wild birds.

Aseptic meningitis and viral myelitis.

PubMed

Irani, David N

2008-08-01

Meningitis and myelitis represent common and very infrequent viral infections of the central nervous system, respectively. The number of cases of viral meningitis that occurs annually exceeds the total number of meningitis cases caused by all other etiologies combined. Focal central nervous system infections, such as occur in the spinal cord with viral myelitis, are much less common and may be confused with noninfectious disorders that cause acute flaccid paralysis. This article reviews some of the important clinical features, epidemiology, diagnostic approaches, and management strategies for patients with aseptic meningitis and viral myelitis. Particular focus is placed on the diseases caused by enteroviruses, which as a group account for most aseptic meningitis cases and many focal infections of the spinal cord.

Temporary Mental Nerve Paresthesia Originating from Periapical Infection

PubMed Central

Genc Sen, Ozgur; Kaplan, Volkan

2015-01-01

Many systemic and local factors can cause paresthesia, and it is rarely caused by infections of dental origin. This report presents a case of mental nerve paresthesia caused by endodontic infection of a mandibular left second premolar. Resolution of the paresthesia began two weeks after conventional root canal treatment associated with antibiotic therapy and was completed in eight weeks. One year follow-up radiograph indicated complete healing of the radiolucent periapical lesion. The tooth was asymptomatic and functional. PMID:26345692

[Immune system and influenza virus].

PubMed

Wierzbicka-Woś, Anna; Tokarz-Deptuła, Beata; Deptuła, Wiesław

2015-02-15

Influenza viruses are a significant cause of respiratory infections, causing 3-5 million clinical infections and 250-500 thousand deaths per year. Infections caused by the influenza virus induce a host immune response at the non-specific and specific level (defined as natural and acquired), which leads to limitation of virus replication. Moreover the elements of immunological memory are induced so that they can protect against subsequent infection by the influenza virus. However, there is still no effective way for the total elimination of this virus, and the only effective method to combat this pathogen appears to be vaccination, which through immune system activation greatly limits its spread. The present paper presents the immune reaction at different levels in response to the influenza virus after entering the body and the mechanisms of the influenza virus for avoiding reactions of the immune system, which correspond to its high variability at the molecular level. Moreover, in this paper we describe various methods of stimulating the organism's immune systems with different generations of vaccines and their effectiveness in the fight against this pathogen.

Recurrent Infections May Signal Immunodeficiencies

MedlinePlus

... FAAAAI Your immune system is constantly on the defense-fighting germs that could cause infections. Sometimes the “ ... produce. Did You Know? • The first lines of defense against infection are your skin and the membranes ...

Molecular mechanisms of cryptococcal meningitis

PubMed Central

Liu, Tong-Bao; Perlin, David; Xue, Chaoyang

2012-01-01

Fungal meningitis is a serious disease caused by a fungal infection of the central nervous system (CNS) mostly in individuals with immune system deficiencies. Fungal meningitis is often fatal without proper treatment, and the mortality rate remains unacceptably high even with antifungal drug interventions. Currently, cryptococcal meningitis is the most common fungal meningitis in HIV-1/AIDS, and its disease mechanism has been extensively studied. The key steps for fungi to infect brain and cause meningitis after establishment of local infection are the dissemination of fungal cells to the bloodstream and invasion through the blood brain barrier to reach the CNS. In this review, we use cryptococcal CNS infection as an example to describe the current molecular understanding of fungal meningitis, including the establishment of the infection, dissemination, and brain invasion. Host and microbial factors that contribute to these infection steps are also discussed. PMID:22460646

Infective Endocarditis Presenting as Bilateral Orbital Cellulitis: An Unusual Case

PubMed Central

Hasan, Badar; Ukani, Rehman; Pauly, Rebecca R

2017-01-01

Orbital cellulitis is a severe and sight-threatening infection of orbital tissues posterior to the orbital septum. The most common causes of orbital cellulitis are rhinosinusitis, orbital trauma, and surgery. Infective endocarditis (IE) is a systemic infection that begins on cardiac valves and spreads by means of the bloodstream to peripheral organs. Septic emboli can spread to any organ including the eyes and can cause focal or diffuse ophthalmic infection. Ocular complications of IE classically include Roth’s spots, subconjunctival hemorrhages, chorioretinitis, and endophthalmitis. IE as a cause of orbital cellulitis has been described by only one author in the literature. Here, we present a very rare case of bilateral orbital cellulitis caused by IE. Through this case, we aim to create awareness of the potential for serious ocular complications in IE and provide an overview of the management. PMID:28721318

IgE antibodies in toxoplasmosis.

PubMed

Matowicka-Karna, Joanna; Kemona, Halina

2014-05-15

Toxoplasmosis is a worldwide infection caused by the intracellular parasite Toxoplasma gondii. At least a third of the world human population is infected with the parasite, making it one of the most successful parasitic infections. Primary maternal infection may cause health-threatening sequelae for the fetus, or even cause death of the uterus. Reactivation of a latent infection in immune deficiency conditions such as AIDS and organ transplantation can cause fatal toxoplasmic encephalitis. Toxoplasmosis is a major cause of chorioretinitis, especially in individuals with impaired immune systems. In the acute phase, directly after invading the body, T. gondii begins to multiply rapidly. In the majority of cases acquired toxoplasmosis is asymptomatic. In the second week of infection, specific IgM antibodies are present in the blood. IgE antibodies appear at the same time, slightly preceding specific IgA antibodies. The concentration of IgE can be one of the parameters used for diagnosing an infection with T. gondii. Laboratory diagnosis, i.e. IgE and serologic assays, plays the main role in the diagnosis of congenital infection and assists in the confirmatory diagnosis of toxoplasmic encephalitis and ocular toxoplasmosis. This article is a review of IgE in toxoplasmosis.

Noncongenital central nervous system infections in children: radiology review.

PubMed

Acosta, Jorge Humberto Davila; Rantes, Claudia Isabel Lazarte; Arbelaez, Andres; Restrepo, Feliza; Castillo, Mauricio

2014-06-01

Infections of the central nervous system (CNS) are a very common worldwide health problem in childhood with significant morbidity and mortality. In children, viruses are the most common cause of CNS infections, followed by bacterial etiology, and less frequent due to mycosis and other causes. Noncomplicated meningitis is easier to recognize clinically; however, complications of meningitis such as abscesses, infarcts, venous thrombosis, or extra-axial empyemas are difficult to recognize clinically, and imaging plays a very important role on this setting. In addition, it is important to keep in mind that infectious process adjacent to the CNS such as mastoiditis can develop by contiguity in an infectious process within the CNS. We display the most common causes of meningitis and their complications.

Central nervous system manifestations of Angiostrongylus cantonensis infection.

PubMed

Martins, Yuri C; Tanowitz, Herbert B; Kazacos, Kevin R

2015-01-01

Over 20 species of Angiostrongylus have been described from around the world, but only Angiostrongylus cantonensis has been confirmed to cause central nervous system disease in humans. A neurotropic parasite that matures in the pulmonary arteries of rats, A. cantonensis is the most common cause of eosinophilic meningitis in southern Asia and the Pacific and Caribbean islands. The parasite can also cause encephalitis/encephalomyelitis and rarely ocular angiostrongyliasis. The present paper reviews the life cycle, epidemiology, pathogenesis, clinical features, diagnosis, treatment, prevention and prognosis of A. cantonesis infection. Emphasis is given on the spectrum of central nervous system manifestations and disease pathogenesis. Copyright © 2014 Elsevier B.V. All rights reserved.

Eumycotic mycetoma caused by Cladophialophora bantiana in a patient with systemic lupus erythematosus.

PubMed

Werlinger, Kelly D; Yen Moore, Angela

2005-05-01

We present the case of a 31-year-old patient who developed widespread mycetoma across her back and shoulders caused by Cladophialophora bantiana 16 years after injury to those sites from tornado debris. The patient also had a history of systemic lupus erythematosus treated with systemic steroids. Systemic antifungal treatment with fluconazole and itraconazole proved ineffective, and surgical debridement was required. Nine other culture-confirmed cases of cutaneous infection with this organism have been reported worldwide. This type of infection can occur in immunocompromised or immunocompetent patients, and may respond to systemic antifungals or surgery.

Complicated infective endocarditis: a case series.

PubMed

Kim, Joo Seop; Kang, Min-Kyung; Cho, A Jin; Seo, Yu Bin; Kim, Kun Il

2017-05-08

Infective endocarditis is associated with not only cardiac complications but also neurologic, renal, musculoskeletal, and systemic complications related to the infection, such as embolization, metastatic infection, and mycotic aneurysm. We report three cases (the first patient is Chinese and the other two are Koreans) of complicated infective endocarditis; two of the cases were associated with a mycotic aneurysm, and one case was associated with a splenic abscess. One case of a patient with prosthetic valve endocarditis was complicated by intracerebral hemorrhage caused by mycotic aneurysm rupture. A second case of a patient with right-sided valve endocarditis associated with a central catheter was complicated by an abdominal aortic mycotic aneurysm. The third patient had a splenic infarction and abscess associated with infected cardiac thrombi. Complicated infective endocarditis is rare and is associated with cardiac, neurologic, renal, musculoskeletal, and systemic complications related to infection, such as embolization, metastatic infection, and mycotic aneurysm. Infective endocarditis caused by Staphylococcus aureus is more frequently associated with complications. Because the mortality rate increases when complications develop, aggressive antibiotic therapy and surgery, combined with specific treatments for the complications, are necessary.

Acute abdomen caused by brucellar hepatic abscess.

PubMed

Ibis, Cem; Sezer, Atakan; Batman, Ali K; Baydar, Serkan; Eker, Alper; Unlu, Ercument; Kuloglu, Figen; Cakir, Bilge; Coskun, Irfan

2007-10-01

Brucellosis is a zoonotic infection that is transmitted from animals to humans by ingestion of infected food products, direct contact with an infected animal, or aerosol inhalation. The disease is endemic in many countries, including the Mediterranean basin, the Middle East, India, Mexico, Central and South America and, central and southwest Asia. Human brucellosis is a systemic infection with a wide clinical spectrum. Although hepatic involvement is very common during the course of chronic brucellosis, hepatic abscess is a very rare complication of Brucella infection. We present a case of hepatic abscess caused by Brucella, which resembled the clinical presentation of surgical acute abdomen.

Bacteremia caused by a rare pathogen - Chromobacterium violaceum: a case report from Nepal.

PubMed

Parajuli, Narayan Prasad; Bhetwal, Anjeela; Ghimire, Sumitra; Maharjan, Anjila; Shakya, Shreena; Satyal, Deepa; Pandit, Roshan; Khanal, Puspa Raj

2016-01-01

Chromobacterium violaceum is a gram negative saprophytic bacterium, prevalent in tropical and subtropical climates. Infections caused by C. violaceum are very uncommon, yet it can cause severe systemic infections with higher mortality when entered into the bloodstream through open wound. A case of symptomatic bacteremia in a woman caused by C. violaceum was identified recently at a tertiary care teaching hospital in Nepal. Timely diagnosis by microbiological methods and rapid administration of antimicrobials led to a successful treatment of this life-threatening infection in this case. From this experience, we suggest to include this bacterium in the differential diagnosis of sepsis, especially when abraded skin is exposed to soil or stagnant water in tropical areas. The precise antimicrobial selection and timely administration should be considered when this infection is suspected.

Guillain-Barre Syndrome

MedlinePlus

Guillain-Barre syndrome is a rare disorder that causes your immune system to attack your peripheral nervous system (PNS). The PNS ... your brain. No one knows what causes the syndrome. Sometimes it is triggered by an infection, surgery, ...

Lung Lesions During Fever of Unknown Origin.

PubMed

Krupa, Renata; Zielonka, Tadeusz M; Hadzik-Blaszczyk, Malgorzata; Wardyn, Kazimierz A; Zycinska, Katarzyna

2017-01-01

Fever of unknown origin (FUO) remains one of the most difficult diagnostic challenges. The causes of FUO can be various diseases located in different organs. The aim of the study was to determine the prevalence and nature of pulmonary lesions during FUO. One hundred and sixty one patients with FUO participated in this prospective study. We performed a detailed comprehensive history, physical examination, and a wide spectrum of tests. The most common causes of FUO were infections (39%), autoimmune conditions (28%), and neoplasms (17%). Lung lesions were found in 30% of patients. In this group 35% were infections, 30% autoimmune diseases, and 4% cancer. Among patients with respiratory infections, there were cases of tuberculosis, atypical pneumonia, lung abscess, and bronchiectases. Autoimmune pulmonary lesions were observed during vasculitis and systemic lupus. The causes of FUO in the group of patients with lung lesions were also pulmonary embolism, sarcoidosis, and pulmonary fibrosis. Chest CT played an important role in the diagnosis of the causes of FUO with pulmonary manifestations. Pulmonary lesions are a common cause of FUO. Most FUO with pulmonary lesions are recognized during infections and autoimmune diseases. An important part of diagnosing FUO is a detailed evaluation of the respiratory system.

Chronic Lyme Disease and Co-infections: Differential Diagnosis

PubMed Central

Berghoff, Walter

2012-01-01

In Lyme disease concurrent infections frequently occur. The clinical and pathological impact of co-infections was first recognized in the 1990th, i.e. approximately ten years after the discovery of Lyme disease. Their pathological synergism can exacerbate Lyme disease or induce similar disease manifestations. Co-infecting agents can be transmitted together with Borrelia burgdorferi by tick bite resulting in multiple infections but a fraction of co-infections occur independently of tick bite. Clinically relevant co-infections are caused by Bartonella species, Yersinia enterocolitica, Chlamydophila pneumoniae, Chlamydia trachomatis, and Mycoplasma pneumoniae. In contrast to the USA, human granulocytic anaplasmosis (HGA) and babesiosis are not of major importance in Europe. Infections caused by these pathogens in patients not infected by Borrelia burgdorferi can result in clinical symptoms similar to those occurring in Lyme disease. This applies particularly to infections caused by Bartonella henselae, Yersinia enterocolitica, and Mycoplasma pneumoniae. Chlamydia trachomatis primarily causes polyarthritis. Chlamydophila pneumoniae not only causes arthritis but also affects the nervous system and the heart, which renders the differential diagnosis difficult. The diagnosis is even more complex when co-infections occur in association with Lyme disease. Treatment recommendations are based on individual expert opinions. In antibiotic therapy, the use of third generation cephalosporins should only be considered in cases of Lyme disease. The same applies to carbapenems, which however are used occasionally in infections caused by Yersinia enterocolitica. For the remaining infections predominantly tetracyclines and macrolides are used. Quinolones are for alternative treatment, particularly gemifloxacin. For Bartonella henselae, Chlamydia trachomatis, and Chlamydophila pneumoniae the combination with rifampicin is recommended. Erythromycin is the drug of choice for Campylobacter jejuni. PMID:23400696

Impact of Serum Vancomycin Trough Levels in the Treatment of Central Nervous System Shunt Infections Caused by Coagulase-Negative Staphylococci.

PubMed

Gibson, Ashley; Kaplan, Sheldon L; Vallejo, Jesus G

2018-04-26

Coagulase-negative staphylococci (CoNS) are a common cause of pediatric ventricular shunt infections. The Infectious Diseases Society of America recommends vancomycin serum troughs of 15-20 µg/mL when treating CoNS shunt infections in adult patients. We report a series of pediatric cases of CoNS shunt infections in which clinical cure was obtained with troughs < 15 µg/mL. These findings question the relevance of this recommendation in pediatric patients. © 2018 S. Karger AG, Basel.

Dermatologic Infectious Diseases in International Travelers.

PubMed

Wilson, Mary E.; Chen, Lin H.

2004-02-01

Skin lesions provide an important clue to the diagnoses of many infections in returned travelers. New information related to epidemiology, recognition, diagnosis, or management is described for the systemic infections--dengue fever, several of the rickettsial infections, African trypanosomiasis, and coccidioidomycosis. Many pathogens cause focal skin findings. Recent findings are presented for cutaneous leishmaniasis, Buruli ulcer, gnatho-stomiasis, cutaneous larva migrans, myiasis, tungiasis, and scabies. This paper describes the most common skin problems in returning travelers and outlines the types of infections that cause skin lesions, as defined by morphologic characteristics.

Unusual ulcerative keratitis caused by Prototheca wickerhamii in a diabetic patient.

PubMed

Narayanan, Niveditha; Vaidehi, D; Dhanurekha, L; Therese, K Lily; Rajagopal, Rama; Natarajan, Radhika; Lakshmipathy, Meena

2018-02-01

The purpose of the study was to report a case of ulcerative keratitis caused by an unusual algae Prototheca wickerhamii in a diabetic patient. This study design was a case report. A 46-year-old male, who was a known diabetic for 3 years, had an injury to the left cornea with the sparks of fire from wielding at work that developed into an ulcerative keratitis over a period of next 3 months as the patient was not on any medication. Corneal scraping culture report and Vitek 2 system investigation result confirmed it to be a P. wickerhamii infection. The patient was started on intensive topical 1% voriconazole and 5% natamycin for 1 month and with no improvement subsequently underwent penetrating keratoplasty. No recurrence of infection postoperatively was noted. This opportunistic algae rarely known to cause human eye infections is so far reported in either patients with severe systemic immunosuppression causing posterior segment eye involvement or as postcorneal surgery infections. We report an ulcerative keratitis by P. wickerhamii in a diabetic patient post corneal trauma with no prior ocular surgery.

Unusual ulcerative keratitis caused by Prototheca wickerhamii in a diabetic patient

PubMed Central

Narayanan, Niveditha; Vaidehi, D; Dhanurekha, L; Therese, K Lily; Rajagopal, Rama; Natarajan, Radhika; Lakshmipathy, Meena

2018-01-01

The purpose of the study was to report a case of ulcerative keratitis caused by an unusual algae Prototheca wickerhamii in a diabetic patient. This study design was a case report. A 46-year-old male, who was a known diabetic for 3 years, had an injury to the left cornea with the sparks of fire from wielding at work that developed into an ulcerative keratitis over a period of next 3 months as the patient was not on any medication. Corneal scraping culture report and Vitek 2 system investigation result confirmed it to be a P. wickerhamii infection. The patient was started on intensive topical 1% voriconazole and 5% natamycin for 1 month and with no improvement subsequently underwent penetrating keratoplasty. No recurrence of infection postoperatively was noted. This opportunistic algae rarely known to cause human eye infections is so far reported in either patients with severe systemic immunosuppression causing posterior segment eye involvement or as postcorneal surgery infections. We report an ulcerative keratitis by P. wickerhamii in a diabetic patient post corneal trauma with no prior ocular surgery. PMID:29380790

[Cryptococcal meningitis as a diagnostic problem in a patient with SLE--case report].

PubMed

Bosnić, Dubravka; Cerovec, Mislav; Anić, Branimir; Mayer, Miroslav; Sentić, Mirna; Baresić, Marko; Markeljević, Jasenka; Cikes, Nada

2008-01-01

Systemic erythematosus lupus (SLE) is a disease with wide range of clinical manifestations, signs and symptoms. Disease outcome depends mostly on the affection of kidneys and central nervous system by the disease. Very important cause of death in patients with SLE is infection. Infections are very common among these patients due to aggressive immunosuppressive treatment that is needed for the disease inflammatory activity control. In this case report we have presented a patient with SLE who initially had severe renal affection, but also complications of immunosuppressive therapy that was administered. Even though the disease was accidentally diagnosed, it had a severe clinical progress. Because of lupus nephropathy, in the early phase of the disease we administered aggressive immunosuppressive therapy (combined parenteral therapy of glucocorticoides and cyclophosphamide). As an outcome of the combined effect of disease and immunosuppressive agents used in the treatment of the disease, the patient had increased infective diathesis (repeated infections caused by S. enteritidis--urinary infections and sepsis). During one of the disease flares the patient was hospitalized an opportunistic infection developed. It was meningitis caused by C. neoformans. This opportunistic mycosis infection presented with clinically totally nonspecific signs and symptoms of CNS affection. Therefore, we suspected affection of CNS with SLE. Even though all diagnostic procedures were made on time and that adequate antifungal and supportive agents were applied very early after the infection onset, the outcome was fatal. Because of infective diathesis in patients with SLE, which present with common and opportunistic infections, and due to high mortality rates caused by these infections, we have tried to emphasise the importance of taking adequate specimens early after infection outcome for these rare infective agents like C. neophormans. In recent medical literature are dominant cases reported in Asia. Reports from Europe are very rare, and this case is the one of that kind in Croatia.

Oxylipin Biosynthesis Genes Positively Regulate Programmed Cell Death during Compatible Infections with the Synergistic Pair Potato Virus X-Potato Virus Y and Tomato Spotted Wilt Virus

PubMed Central

García-Marcos, Alberto; Pacheco, Remedios; Manzano, Aranzazu; Aguilar, Emmanuel

2013-01-01

One of the most severe symptoms caused by compatible plant-virus interactions is systemic necrosis, which shares common attributes with the hypersensitive response to incompatible pathogens. Although several studies have identified viral symptom determinants responsible for systemic necrosis, mechanistic models of how they contribute to necrosis in infected plants remain scarce. Here, we examined the involvement of different branches of the oxylipin biosynthesis pathway in the systemic necrosis response caused either by the synergistic interaction of Potato virus X with Potato virus Y (PVX-PVY) or by Tomato spotted wilt virus (TSWV) in Nicotiana benthamiana. Silencing either 9-lipoxygenase (LOX), 13-LOX, or α-dioxygenase-1 (α-DOX-1) attenuated the programmed cell death (PCD)-associated symptoms caused by infection with either PVX-PVY or TSWV. In contrast, silencing of the jasmonic acid perception gene, COI1 (Coronatine insensitive 1), expedited cell death during infection with compatible viruses. This correlated with an enhanced expression of oxylipin biosynthesis genes and dioxygenase activity in PVX-PVY-infected plants. Moreover, the Arabidopsis thaliana double lox1 α-dox-1 mutant became less susceptible to TSWV infection. We conclude that oxylipin metabolism is a critical component that positively regulates the process of PCD during compatible plant-virus interactions but does not play a role in restraining virus accumulation in planta. PMID:23487466

Exploratory Study on Pathogenesis of Far-Eastern Spotted Fever

PubMed Central

Duan, Changsong; Meng, Yanfen; Wang, Xile; Xiong, Xiaolu; Wen, Bohai

2011-01-01

Far-eastern spotted fever is an emerging disease caused by Rickettsia heilongjiangensis, a tick-borne obligate intracellular bacterium. In this study, R. heilongjiangensis was used to infect BALB/c mice by inoculation of retro-orbital venous plexus to imitate a blood infection caused by tick biting. We found that R. heilongjiangensis rapidly entered the circulation for systemic dissemination and the pathogen existed in liver, spleen, lungs, and brain of the mice at least 9 days post-infection (p.i.). Severe pathological lesions were observed in liver, lungs, and brain at Day 6 p.i. In addition, the elevated levels of inflammatory cytokines, including interferon-γ, tumor necrosis factor, and CC chemokine, were detected in the infected organs at Day 3 p.i. Our results reveal that R. heilongjiangensis may cause an infection in BALB/c mice and the pathological lesions in the infected mice are associated with host inflammatory response induced by R. heilongjiangensis. PMID:21896812

[Infections related to recreational waters].

PubMed

Doménech-Sánchez, Antonio; Olea, Francisco; Berrocal, Clara I

2008-11-01

Recreational waters are a source of infection by several microorganisms causing acute gastrointestinal, cutaneous and respiratory illnesses. Cryptosporidium, noroviruses and enteropathogenic Escherichia coli strains are the most important causes of diarrhea, while Pseudomonas and Staphylococcus aureus are the main causes of cutaneous infections, and Legionella is the major cause of acute lower respiratory disease. Approximately 90% of outbreaks occur in treated recreational waters (swimming pools, spas and recreational parks), while the remaining 10% arise from natural waters used for leisure (bathing in rivers, beaches, etc). In spas, most infections are caused by thermophilic bacteria, such as Pseudomonas and Legionella, since overgrowth of these bacteria is facilitated by the direct effect of temperature and, indirectly, by the evaporation of the disinfectant. Outbreaks related to recreational waters usually reflect deficient control of the system: a low level of disinfectant, or the use of an inappropriate disinfectant, insufficient maintenance and cleaning of the installation, higher than recommended usage, and failure of the disinfectant dosage system. The correct design, maintenance and use of these facilities drastically lower the risk of infections from recreational waters. Thus, other key actions to minimize this risk are the existence of, and compliance with, regulatory rules, as well as educational campaigns on good hygiene practices directed at users. Rapid etiologic diagnosis of affected patients, together with an epidemiological survey and detection of the pathogen implicated in water samples are the keys to outbreak control.

Comparison of multi- and hyperspectral imaging data of leaf rust infected wheat plants

NASA Astrophysics Data System (ADS)

Franke, Jonas; Menz, Gunter; Oerke, Erich-Christian; Rascher, Uwe

2005-10-01

In the context of precision agriculture, several recent studies have focused on detecting crop stress caused by pathogenic fungi. For this purpose, several sensor systems have been used to develop in-field-detection systems or to test possible applications of remote sensing. The objective of this research was to evaluate the potential of different sensor systems for multitemporal monitoring of leaf rust (puccinia recondita) infected wheat crops, with the aim of early detection of infected stands. A comparison between a hyperspectral (120 spectral bands) and a multispectral (3 spectral bands) imaging system shows the benefits and limitations of each approach. Reflectance data of leaf rust infected and fungicide treated control wheat stand boxes (1sqm each) were collected before and until 17 days after inoculation. Plants were grown under controlled conditions in the greenhouse and measurements were taken under consistent illumination conditions. The results of mixture tuned matched filtering analysis showed the suitability of hyperspectral data for early discrimination of leaf rust infected wheat crops due to their higher spectral sensitivity. Five days after inoculation leaf rust infected leaves were detected, although only slight visual symptoms appeared. A clear discrimination between infected and control stands was possible. Multispectral data showed a higher sensitivity to external factors like illumination conditions, causing poor classification accuracy. Nevertheless, if these factors could get under control, even multispectral data may serve a good indicator for infection severity.

Mobile Microbiome

PubMed Central

Han, Y.W.; Wang, X.

2013-01-01

The link between oral infections and adverse systemic conditions has attracted much attention in the research community. Several mechanisms have been proposed, including spread of the oral infection due to transient bacteremia resulting in bacterial colonization in extra-oral sites, systemic injury by free toxins of oral pathogens, and systemic inflammation caused by soluble antigens of oral pathogens. Mounting evidence supports a major role of the systemic spread of oral commensals and pathogens to distant body sites causing extra-oral infections and inflammation. We review here the most recent findings on systemic infections and inflammation complicated by oral bacteria, including cardiovascular disease, adverse pregnancy outcomes, rheumatoid arthritis, inflammatory bowel disease and colorectal cancer, respiratory tract infections, and organ inflammations and abscesses. The recently identified virulence mechanisms of oral species Fusobacterium nucleatum, Porphyromonas gingivalis, Streptococcus mutans, and Campylobacter rectus are also reviewed. A pattern emerges indicating that only select subtype(s) of a given species, e.g., F. nucleatum subspecies animalis and polymorphum and S. mutans non-c serotypes, are prone to extra-oral translocation. These findings advocate the importance of identification and quantification of potential pathogens at the subtype levels for accurate prediction of disease potential. PMID:23625375

Systemic toxoplasmosis and concurrent porcine circovirus-2 infection in a pig.

PubMed

Klein, S; Wendt, M; Baumgärtner, W; Wohlsein, P

2010-01-01

Systemic toxoplasmosis and concurrent infection with porcine circovirus-2 (PCV-2) was diagnosed in a fattening pig. Clinical examination of the herd showed that up to 30% of the pigs of this weight group suffered from severe respiratory signs including sneezing and coughing, with a mortality rate of up to 5%. Gross necropsy examination revealed severe interstitial pneumonia and generalized lymphadenopathy. On microscopical examination there was necrotizing inflammation of the lung, adrenal glands and lymph nodes, associated with lymphoid depletion, cytoplasmic basophilic botryoid inclusion bodies and protozoal microorganisms. Infection with Toxoplasma gondii was confirmed by immunohistochemistry (IHC). Polymerase chain reaction analysis, in-situ hybridization and IHC confirmed systemic PCV-2 infection. These findings, associated with the respiratory signs and lesions in lymphoid tissues, are characteristic for post-weaning multisystemic wasting syndrome (PMWS). In this case, immunosuppression by PCV-2 may have triggered systemic toxoplasmosis, or immune stimulation caused by coinfection with T. gondii may have caused extensive replication of PCV-2. Copyright 2009 Elsevier Ltd. All rights reserved.

Invasive Non-Typhoidal Salmonella Typhimurium ST313 Are Not Host-Restricted and Have an Invasive Phenotype in Experimentally Infected Chickens

PubMed Central

Parsons, Bryony N.; Humphrey, Suzanne; Salisbury, Anne Marie; Mikoleit, Julia; Hinton, Jay C. D.; Gordon, Melita A.; Wigley, Paul

2013-01-01

Salmonella enterica serovar Typhimurium Sequence Type (ST) 313 is a major cause of invasive non-Typhoidal salmonellosis in sub-Saharan Africa. No animal reservoir has been identified, and it has been suggested that ST313 is adapted to humans and transmission may occur via person-to-person spread. Here, we show that ST313 cause severe invasive infection in chickens as well as humans. Oral infection of chickens with ST313 isolates D23580 and Q456 resulted in rapid infection of spleen and liver with all birds infected at these sites by 3 days post-infection. In contrast, the well-defined ST19 S. Typhimurium isolates F98 and 4/74 were slower to cause invasive disease. Both ST19 and ST313 caused hepatosplenomegaly, and this was most pronounced in the ST313-infected animals. At 3 and 7 days post-infection, colonization of the gastrointestinal tract was lower in birds infected with the ST313 isolates compared with ST19. Histological examination and expression of CXCL chemokines in the ileum showed that both D23580 (ST313) and 4/74 (ST19) strains caused increased CXCL expression at 3 days post-infection, and this was significantly higher in the ileum of D23580 vs 4/74 infected birds. At 7 days post-infection, reduced chemokine expression occurred in the ileum of the D23580 but not 4/74-infected birds. Histological analysis showed that D23580 infection resulted in rapid inflammation and pathology including villous flattening and fusion at 3 days post-infection, and subsequent resolution by 7 days. In contrast, 4/74 induced less inflammation and pathology at 3 days post-infection. The data presented demonstrate that ST313 is capable of causing invasive disease in a non-human host. The rapid invasive nature of infection in the chicken, coupled with lower gastrointestinal colonization, supports the hypothesis that ST313 is a distinct pathovariant of S. Typhimurium that has evolved to become a systemic pathogen that can cause disease in several hosts. PMID:24130915

Are sex ratio distorting endosymbionts responsible for mating system variation among dance flies (Diptera: Empidinae)?

PubMed Central

Herridge, Elizabeth J.; Ness, Rob W.; Bussière, Luc F.

2017-01-01

Maternally inherited bacterial endosymbionts are common in many arthropod species. Some endosymbionts cause female-biased sex ratio distortion in their hosts that can result in profound changes to a host’s mating behaviour and reproductive biology. Dance flies (Diptera: Empidinae) are well known for their unusual reproductive biology, including species with female-specific ornamentation and female-biased lek-like swarming behaviour. The cause of the repeated evolution of female ornaments in these flies remains unknown, but is probably associated with female-biased sex ratios in individual species. In this study we assessed whether dance flies harbour sex ratio distorting endosymbionts that might have driven these mating system evolutionary changes. We measured the incidence and prevalence of infection by three endosymbionts that are known to cause female-biased sex ratios in other insect hosts (Wolbachia, Rickettsia and Spiroplasma) across 20 species of dance flies. We found evidence of widespread infection by all three symbionts and variation in sex-specific prevalence across the taxa sampled. However, there was no relationship between infection prevalence and adult sex ratio measures and no evidence that female ornaments are associated with high prevalences of sex-biased symbiont infections. We conclude that the current distribution of endosymbiont infections is unlikely to explain the diversity in mating systems among dance fly species. PMID:28609446

Are sex ratio distorting endosymbionts responsible for mating system variation among dance flies (Diptera: Empidinae)?

PubMed

Murray, Rosalind L; Herridge, Elizabeth J; Ness, Rob W; Bussière, Luc F

2017-01-01

Maternally inherited bacterial endosymbionts are common in many arthropod species. Some endosymbionts cause female-biased sex ratio distortion in their hosts that can result in profound changes to a host's mating behaviour and reproductive biology. Dance flies (Diptera: Empidinae) are well known for their unusual reproductive biology, including species with female-specific ornamentation and female-biased lek-like swarming behaviour. The cause of the repeated evolution of female ornaments in these flies remains unknown, but is probably associated with female-biased sex ratios in individual species. In this study we assessed whether dance flies harbour sex ratio distorting endosymbionts that might have driven these mating system evolutionary changes. We measured the incidence and prevalence of infection by three endosymbionts that are known to cause female-biased sex ratios in other insect hosts (Wolbachia, Rickettsia and Spiroplasma) across 20 species of dance flies. We found evidence of widespread infection by all three symbionts and variation in sex-specific prevalence across the taxa sampled. However, there was no relationship between infection prevalence and adult sex ratio measures and no evidence that female ornaments are associated with high prevalences of sex-biased symbiont infections. We conclude that the current distribution of endosymbiont infections is unlikely to explain the diversity in mating systems among dance fly species.

Etiologic Aspect of Sarcoidosis as an Allergic Endogenous Infection Caused by Propionibacterium acnes

PubMed Central

2013-01-01

Sarcoidosis is a systemic granulomatous disease of unknown etiology. Propionibacterium acnes is the only microorganism that has been isolated from sarcoid lesions. Many P. acnes have been detected in sarcoid lymph nodes using quantitative PCR and in sarcoid granulomas by in situ hybridization. P. acnes trigger factor protein causes a cellular immune response only in sarcoid patients and induces pulmonary granulomas in mice sensitized with the protein and adjuvant, but only those with latent P. acnes infection in their lungs. Eradication of P. acnes by antibiotics prevents the development of granulomas in this experimental model. Although P. acnes is the most common commensal bacterium in the lungs and lymph nodes, P. acnes-specific antibody detected the bacterium within sarcoid granulomas of these organs. P. acnes can cause latent infection in the lung and lymph node and persist in a cell-wall-deficient form. The dormant form is activated endogenously under certain conditions and proliferates at the site of latent infection. In patients with P. acnes hypersensitivity, granulomatous inflammation is triggered by intracellular proliferation of the bacterium. Proliferating bacteria may escape granulomatous isolation, spreading to other organs. Latent P. acnes infection in systemic organs can be reactivated by another triggering event, leading to systemic sarcoidosis. PMID:23844371

The pathogenesis of measles.

PubMed

de Vries, Rory D; Mesman, Annelies W; Geijtenbeek, Teunis B H; Duprex, W Paul; de Swart, Rik L

2012-06-01

Measles is an important cause of childhood morbidity and mortality in developing countries. Measles virus (MV) is transmitted via the respiratory route and causes systemic disease. Over the last decade, identification of new cellular receptors and studies in animal models have challenged the historic concepts of measles pathogenesis. It is thought that MV enters the host by infection of alveolar macrophages and/or dendritic cells in the airways, and is amplified in local lymphoid tissues. Viremia mediated by infected CD150+ lymphocytes results in systemic dissemination. Infection of lymphocytes and dendritic cells in the respiratory submucosa facilitates basolateral infection of epithelial cells via the newly identified receptor Nectin-4. Concomitant and extensive epithelial damage may contribute to efficient transmission to the next host. Copyright © 2012 Elsevier B.V. All rights reserved.

Actinobaculum schaalii, a new cause of knee prosthetic joint infection in elderly.

PubMed

Jacquier, H; Benmansour, H; Zadegan, F; Hannouche, D; Micaelo, M; Mongiat-Artus, P; Salomon, E; Cambau, E; Berçot, B

2016-08-01

Actinobaculum schaalii is an emerging pathogen particularly involved in urinary tract infection of elderly people and/or patient with urological risk factors of urinary tract infection. This microorganism is a difficult-to-diagnose pathogen and is rarely involved in systemic or deep infections. Here, we report the first case of prosthetic joint infection due to A. schaalii in an 84-year-old man with a benign prostatic hyperplasia associated with chronic retention of urine. This case underlines the importance to optimize the diagnosis of emerging uropathogens as A. schaalii, to prevent systemic infections, particularly in patients with orthopaedic implants.

Infection in Venous Leg Ulcers: Considerations for Optimal Management in the Elderly.

PubMed

Pugliese, Douglas J

2016-02-01

Venous leg ulcers are the most common cause of chronic leg wounds, accounting for up to 70 % of all chronic leg ulcers and carrying with them a significant morbidity, especially for elderly patients. Among people aged 65 years and older, the annual prevalence is 1.7 %. Billions of dollars per year are spent caring for patients with these often difficult-to-heal and sometimes recurrent chronic wounds. Chronic non-healing wounds of the lower extremities are susceptible to microbial invasion and can lead to serious complications, such as delayed healing, cellulitis, enlargement of wound size, debilitating pain, and deeper wound infections causing systemic illness. Recognition and treatment of the infected venous leg ulcer is an essential skill set for any physician caring for geriatric patients. Most physicians rely on subjective clinical signs and patient-reported symptoms in the evaluation of infected chronic wounds. The conventional bacterial culture is a widely available tool for the diagnosis of bacterial infection but can have limitations. Systemic antibiotics, as well as topical antiseptics and antibiotics, can be employed to treat and control infection and critical colonization. Better understanding of microbial biofilms in the wound environment have caused them to emerge as an important reason for non-healing and infection due to their increased resistance to antimicrobial, immunological, and chemical attack. A sound understanding of the microbial-host environment and its complexities, as well as the pathophysiology of venous hypertension, must be appreciated to understand the need for a multimodality approach to treating an infected venous leg ulcer. Other treatment measures are often required, in addition to systemic and topical antibiotics, such as the application of wound bandages, compression therapy, and wound debridement, which can hasten clearance of the infection and help to promote healing.

Central nervous system infection due to Mycobacterium haemophilum in a patient with acquired immunodeficiency syndrome.

PubMed

Buppajarntham, Aubonphan; Apisarnthanarak, Anucha; Rutjanawech, Sasinuj; Khawcharoenporn, Thana

2015-03-01

Mycobacterium haemophilum is an environmental organism that rarely causes infections in humans. We report a patient with acquired immunodeficiency syndrome who had central nervous system infection due to M. haemophilum. The diagnosis required brain tissue procurement and molecular identification method while the treatment outcome was unfavourable. © The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

Term stillbirth caused by oral Fusobacterium nucleatum.

PubMed

Han, Yiping W; Fardini, Yann; Chen, Casey; Iacampo, Karla G; Peraino, Victoria A; Shamonki, Jaime M; Redline, Raymond W

2010-02-01

Intrauterine infection is a recognized cause of adverse pregnancy outcome, but the source of infection is often undetermined. We report a case of stillbirth caused by Fusobacterium nucleatum that originated in the mother's mouth. A woman with pregnancy-associated gingivitis experienced an upper respiratory tract infection at term, followed by stillbirth a few days later. F. nucleatum was isolated from the placenta and the fetus. Examination of different microbial floras from the mother identified the same clone in her subgingival plaque but not in the supragingival plaque, vagina, or rectum. F. nucleatum may have translocated from the mother's mouth to the uterus when the immune system was weakened during the respiratory infection. This case sheds light on patient management for those with pregnancy-associated gingivitis.

Use of antibiotics in the management of postirradiation wound infection and sepsis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Brook, I.

1988-07-01

Ionizing gamma irradiation depresses the host defenses and enhances the susceptibility of the immunocompromised host to local and systemic infection due to endogenous or exogenous microorganisms. Trauma and wounding act synergistically and decrease the survival after exposure to irradiation. The current antimicrobial agents suitable for controlling serious infections and their use in post irradiation local and systemic infection with and without trauma are discussed. The experience gained in managing immunocompromised patients following chemotherapy is reviewed. Empiric single agent or combination agent therapy should be directed at the eradication of potential gram-negative as well as gram-positive pathogens. The most important organismsmore » known to cause these infections are Pseudomonas sp. and Enterobacteriaceae. Management of intra-abdominal infections following trauma should include early surgical correlation and antimicrobials directed against the Bacteroides fragilis group and Enterobacteriaceae. Staphylococcus aureus and Streptococcus pyogenes cause most skin and soft tissue infections following trauma. Chemoprophylaxis of enteric sources of systemic infection can be achieved by antimicrobials that selectively inhibit the Enterobacteriaceae sp. and preserve the anaerobic flora. The management of infection in the injured and irradiated host includes supportive and restorative therapy. Supportive therapy includes debridement and cleansing of wounds, fluids, immunoglobulin, and antimicrobials. Restorative therapy includes definite surgery repair and replenishment of the immune system by use of immunomodulators, growth factors, and bone marrow transplantation. Further studies are needed to examine the usefulness of presently available drugs and experimental agents in the irradiated and traumatized host. 111 references.« less

Necrotizing fasciitis due to Streptococcus mitis caused by accidental human bite.

PubMed

Bastug, Aliye; Kislak, Sumeyye; Mutlu, Nevzat Mehmet; Akcaboy, Zeynep Nur; Koksal, Asude; Sertcelik, Ahmet; Ünlü, Ramazan Erkin; Akinci, Esragul; Bodur, Hurrem

2016-01-31

Human bite wounds are more prone to infection than animal bites, which may cause necrotizing soft tissue infections such as myositis, fasciitis. Both aerobic and anaerobic microorganisms may be responsible, including Streptococcus spp., Staphylococcus aureus, Peptostreptococcus spp. Necrotizing fasciitis is characterized by serious tissue destruction and systemic toxicity with high morbidity and mortality. We report a patient with Streptococcus mitis associated necrotizing fasciitis on the upper extremity resulting from an accidental human bite, which caused nearly fatal infection. Prophylactic antibiotic treatment should be given after a human bite to prevent infection. If the infection signs and symptoms develop, rapid diagnosis, appropriate antibiotic and surgical therapy should be administered immediately. Streptococcus mitis is a viridans streptococcus, usually known as a relatively benign oral streptococcus. To our knowledge, this is the first necrotizing fasciitis case due to Streptococcus mitis after human bite.

Chickenpox

MedlinePlus

... Better? When Should I Call the Doctor? Print What Is Chickenpox? Chickenpox is a viral infection that causes ... weak immune systems or skin disorders like eczema . What Causes Chickenpox? Chickenpox is caused by the varicella-zoster virus (VZV). This ...

Adaptive Immunity to Cryptococcus neoformans Infections

PubMed Central

Mukaremera, Liliane; Nielsen, Kirsten

2017-01-01

The Cryptococcus neoformans/Cryptococcus gattii species complex is a group of fungal pathogens with different phenotypic and genotypic diversity that cause disease in immunocompromised patients as well as in healthy individuals. The immune response resulting from the interaction between Cryptococcus and the host immune system is a key determinant of the disease outcome. The species C. neoformans causes the majority of human infections, and therefore almost all immunological studies focused on C. neoformans infections. Thus, this review presents current understanding on the role of adaptive immunity during C. neoformans infections both in humans and in animal models of disease. PMID:29333430

Rare Orbital Infections ~ State of the Art ~ Part II

PubMed Central

Hamed-Azzam, Shirin; AlHashash, Islam; Briscoe, Daniel; Rose, Geoffrey E; Verity, David H.

2018-01-01

Infections of the orbit and periorbita are relatively frequent. Identifying unusual organisms is crucial because they can cause severe local and systemic morbidity, despite their rarity. Opportunistic infections of the orbit should be considered mainly in debilitated or immunocompromised patients. The key to successful management includes a high index of suspicion, prompt diagnosis, and addressing the underlying systemic disease. This review summarizes unusual infectious processes of the orbit, including mycobacterial, fungal, and parasitic infections, as well as their pathophysiology, symptoms, signs, and treatment. PMID:29719648

Role of Iron Uptake Systems in Pseudomonas aeruginosa Virulence and Airway Infection

PubMed Central

Minandri, Fabrizia; Imperi, Francesco; Frangipani, Emanuela; Bonchi, Carlo; Visaggio, Daniela; Facchini, Marcella; Pasquali, Paolo; Bragonzi, Alessandra

2016-01-01

Pseudomonas aeruginosa is a leading cause of hospital-acquired pneumonia and chronic lung infections in cystic fibrosis patients. Iron is essential for bacterial growth, and P. aeruginosa expresses multiple iron uptake systems, whose role in lung infection deserves further investigation. P. aeruginosa Fe3+ uptake systems include the pyoverdine and pyochelin siderophores and two systems for heme uptake, all of which are dependent on the TonB energy transducer. P. aeruginosa also has the FeoB transporter for Fe2+ acquisition. To assess the roles of individual iron uptake systems in P. aeruginosa lung infection, single and double deletion mutants were generated in P. aeruginosa PAO1 and characterized in vitro, using iron-poor media and human serum, and in vivo, using a mouse model of lung infection. The iron uptake-null mutant (tonB1 feoB) and the Fe3+ transport mutant (tonB1) did not grow aerobically under low-iron conditions and were avirulent in the mouse model. Conversely, the wild type and the feoB, hasR phuR (heme uptake), and pchD (pyochelin) mutants grew in vitro and caused 60 to 90% mortality in mice. The pyoverdine mutant (pvdA) and the siderophore-null mutant (pvdA pchD) grew aerobically in iron-poor media but not in human serum, and they caused low mortality in mice (10 to 20%). To differentiate the roles of pyoverdine in iron uptake and virulence regulation, a pvdA fpvR double mutant defective in pyoverdine production but expressing wild-type levels of pyoverdine-regulated virulence factors was generated. Deletion of fpvR in the pvdA background partially restored the lethal phenotype, indicating that pyoverdine contributes to the pathogenesis of P. aeruginosa lung infection by combining iron transport and virulence-inducing capabilities. PMID:27271740

Interpreting Laboratory Tests in Infection: Making Sense of Biomarkers in Sepsis and Systemic Inflammatory Response Syndrome for Intensive Care Unit Patients.

PubMed

Martin, Jennifer B; Badeaux, Jennifer E

2017-03-01

Sepsis and severe sepsis are leading causes of death in the United States and the most common causes of death among critically ill patients in noncoronary intensive care units. Diagnosis of infection and sepsis is a subjective clinical judgment based on the criteria for systemic inflammatory reaction, which is highly sensitive, not specific, and often misleading in intensively treated patients. Biomarkers are emerging as adjuncts to traditional diagnostic measures. No biomarkers have sufficient specificity or sensitivity to be routinely used in clinical practice, but they can aid in the diagnosis and treatment of infection versus inflammation. Copyright © 2016 Elsevier Inc. All rights reserved.

Mortality from selected diseases that can be transmitted by water - United States, 2003-2009.

PubMed

Gargano, J W; Adam, E A; Collier, S A; Fullerton, K E; Feinman, S J; Beach, M J

2017-06-01

Diseases spread by water are caused by fecal-oral, contact, inhalation, or other routes, resulting in illnesses affecting multiple body systems. We selected 13 pathogens or syndromes implicated in waterborne disease outbreaks or other well-documented waterborne transmission (acute otitis externa, Campylobacter, Cryptosporidium, Escherichia coli (E. coli), free-living ameba, Giardia, Hepatitis A virus, Legionella (Legionnaires' disease), nontuberculous mycobacteria (NTM), Pseudomonas-related pneumonia or septicemia, Salmonella, Shigella, and Vibrio). We documented annual numbers of deaths in the United States associated with these infections using a combination of death certificate data, nationally representative hospital discharge data, and disease-specific surveillance systems (2003-2009). We documented 6,939 annual total deaths associated with the 13 infections; of these, 493 (7%) were caused by seven pathogens transmitted by the fecal-oral route. A total of 6,301 deaths (91%) were associated with infections from Pseudomonas, NTM, and Legionella, environmental pathogens that grow in water system biofilms. Biofilm-associated pathogens can cause illness following inhalation of aerosols or contact with contaminated water. These findings suggest that most mortality from these 13 selected infections in the United States does not result from classical fecal-oral transmission but rather from other transmission routes.

Staphylococcus aureus infections in Australasian neonatal nurseries.

PubMed

Isaacs, D; Fraser, S; Hogg, G; Li, H Y

2004-07-01

To study the incidence and outcome of systemic infections with methicillin sensitive (MSSA) and methicillin resistant Staphylococcus aureus (MRSA) infections in Australasian neonatal nurseries. Prospective longitudinal study of systemic infections (clinical sepsis plus positive cultures of blood and/or cerebrospinal fluid) in 17 Australasian neonatal nurseries. The incidence of early onset sepsis with S aureus, mainly MSSA, was 19 cases per 244 718 live births or 0.08 per 1000. From 1992 to 1994, MRSA infections caused only 8% of staphylococcal infections. From 1995 to 1998, there was an outbreak of MRSA infection, in two Melbourne hospitals. The outbreak resolved, after the use of topical mupirocin and improved handwashing. Babies with MRSA sepsis were significantly smaller than babies with MSSA sepsis (mean birth weight 1093 v 1617 g) and more preterm (mean gestation 27.5 v 30.3 weeks). The mortality of MRSA sepsis was 24.6% compared with 9.9% for MSSA infections. The mortality of early onset MSSA sepsis, however, was 39% (seven of 18) compared with 7.3% of late onset MSSA infection presenting more than two days after birth. S aureus is a rare but important cause of early onset sepsis. Late onset MRSA infections carried a higher mortality than late onset MSSA infections, but babies with early onset MSSA sepsis had a particularly high mortality.

Cervical spondylodiscitis with spinal epidural abscess caused by Aggregatibacter aphrophilus.

PubMed

Pasqualini, Leonella; Mencacci, Antonella; Scarponi, Anna Maria; Leli, Christian; Fabbriciani, Gianluigi; Callarelli, Laura; Schillaci, Giuseppe; Bistoni, Francesco; Mannarino, Elmo

2008-05-01

Spondylodiscitis caused by Aggregatibacter aphrophilus, formerly known as Haemophilus paraphrophilus, is an unusual condition and can be very difficult to diagnose. We report a case of cervical spondylodiscitis complicated by spinal epidural abscess in a 63-year-old woman, without underlying predisposing conditions. The source of infection was identified as a periodontal infection. The patient was successfully treated with systemic antibiotics.

Mutations Allow JC Polyomaviruses to Elude Antibody Recognition | Center for Cancer Research

Cancer.gov

JC polyomavirus (JCV) infects the urinary tract of most adults. In healthy individuals, JCV infection does not cause noticeable symptoms. However, in those with compromised immune systems, JCV can cause a lethal brain disease called progressive multifocal leukoencephalopathy (PML). Data from a recently approved assay to detect serum antibodies specific for the JCV protein VP1

Staphylococcus aureus Central Nervous System Infections in Children.

PubMed

Vallejo, Jesus G; Cain, Alexandra N; Mason, Edward O; Kaplan, Sheldon L; Hultén, Kristina G

2017-10-01

Central nervous system (CNS) infections caused by Staphylococcus aureus are uncommon in pediatric patients. We review the epidemiology, clinical features and treatment in 68 patients with a S. aureus CNS infection evaluated at Texas Children's Hospital. Cases of CNS infection in children with positive cerebrospinal fluid cultures or spinal epidural abscess (SEA) for S. aureus at Texas Children's Hospital from 2001 to 2013 were reviewed. Seventy cases of S. aureus CNS infection occurred in 68 patients. Forty-nine cases (70%) were secondary to a CNS device, 5 (7.1%) were postoperative meningitis, 9 (12.8%) were hematogenous meningitis and 7 (10%) were SEAs. Forty-seven (67.2%) were caused by methicillin-sensitive S. aureus (MSSA) and 23 (32.8%) by methicillin-resistant S. aureus (MRSA). Community-acquired infections were more often caused by MRSA that was clone USA300/pvl. Most patients were treated with nafcillin (MSSA) or vancomycin (MRSA) with or without rifampin. Among patients with MRSA infection, 50% had a serum vancomycin trough obtained with the median level being 10.6 μg/mL (range: 5.4-15.7 μg/mL). Only 1 death was associated with S. aureus infection. The epidemiology of invasive of S. aureus infections continues to evolve with MSSA accounting for most of the infections in this series. The majority of cases were associated with neurosurgical procedures; however, hematogenous S. aureus meningitis and SEA occurred as community-acquired infections in patients without predisposing factors. Patients with MRSA CNS infections had a favorable response to vancomycin, but the beneficial effect of combination therapy or targeting vancomycin trough concentrations of 15-20 μg/mL remains unclear.

A Neuron-Specific Antiviral Mechanism Prevents Lethal Flaviviral Infection of Mosquitoes

PubMed Central

Xiao, Xiaoping; Zhang, Rudian; Pang, Xiaojing; Liang, Guodong; Wang, Penghua; Cheng, Gong

2015-01-01

Mosquitoes are natural vectors for many etiologic agents of human viral diseases. Mosquito-borne flaviviruses can persistently infect the mosquito central nervous system without causing dramatic pathology or influencing the mosquito behavior and lifespan. The mechanism by which the mosquito nervous system resists flaviviral infection is still largely unknown. Here we report that an Aedes aegypti homologue of the neural factor Hikaru genki (AaHig) efficiently restricts flavivirus infection of the central nervous system. AaHig was predominantly expressed in the mosquito nervous system and localized to the plasma membrane of neural cells. Functional blockade of AaHig enhanced Dengue virus (DENV) and Japanese encephalitis virus (JEV), but not Sindbis virus (SINV), replication in mosquito heads and consequently caused neural apoptosis and a dramatic reduction in the mosquito lifespan. Consistently, delivery of recombinant AaHig to mosquitoes reduced viral infection. Furthermore, the membrane-localized AaHig directly interfaced with a highly conserved motif in the surface envelope proteins of DENV and JEV, and consequently interrupted endocytic viral entry into mosquito cells. Loss of either plasma membrane targeting or virion-binding ability rendered AaHig nonfunctional. Interestingly, Culex pipien pallens Hig also demonstrated a prominent anti-flavivirus activity, suggesting a functionally conserved function for Hig. Our results demonstrate that an evolutionarily conserved antiviral mechanism prevents lethal flaviviral infection of the central nervous system in mosquitoes, and thus may facilitate flaviviral transmission in nature. PMID:25915054

Examining the Link between Biofilm Formation and the Ability of Pathogenic Salmonella Strains to Colonize Multiple Host Species

PubMed Central

MacKenzie, Keith D.; Palmer, Melissa B.; Köster, Wolfgang L.; White, Aaron P.

2017-01-01

Salmonella are important pathogens worldwide and a predominant number of human infections are zoonotic in nature. The ability of strains to form biofilms, which is a multicellular behavior characterized by the aggregation of cells, is predicted to be a conserved strategy for increased persistence and survival. It may also contribute to the increasing number of infections caused by ingestion of contaminated fruits and vegetables. There is a correlation between biofilm formation and the ability of strains to colonize and replicate within the intestines of multiple host species. These strains predominantly cause localized gastroenteritis infections in humans. In contrast, there are salmonellae that cause systemic, disseminated infections in a select few host species; these “invasive” strains have a narrowed host range, and most are unable to form biofilms. This includes host-restricted Salmonella serovar Typhi, which are only able to infect humans, and atypical gastroenteritis strains associated with the opportunistic infection of immunocompromised patients. From the perspective of transmission, biofilm formation is advantageous for ensuring pathogen survival in the environment. However, from an infection point of view, biofilm formation may be an anti-virulence trait. We do not know if the capacity to form biofilms prevents a strain from accessing the systemic compartments within the host or if loss of the biofilm phenotype reflects a change in a strain’s interaction with the host. In this review, we examine the connections between biofilm formation, Salmonella disease states, degrees of host adaptation, and how this might relate to different transmission patterns. A better understanding of the dynamic lifecycle of Salmonella will allow us to reduce the burden of livestock and human infections caused by these important pathogens. PMID:29159172

Clinical aspects of feline immunodeficiency and feline leukemia virus infection.

PubMed

Hartmann, Katrin

2011-10-15

Feline leukemia virus (FeLV) and feline immunodeficiency virus (FIV) are retroviruses with a global impact on the health of domestic cats. The two viruses differ in their potential to cause disease. FIV can cause an acquired immunodeficiency syndrome that increases the risk of developing opportunistic infections, neurological diseases, and tumors. In most naturally infected cats, however, FIV itself does not cause severe clinical signs, and FIV-infected cats may live many years without any health problems. FeLV is more pathogenic, and was long considered to be responsible for more clinical syndromes than any other agent in cats. FeLV can cause tumors (mainly lymphoma), bone marrow suppression syndromes (mainly anemia) and lead to secondary infectious diseases caused by suppressive effects of the virus on bone marrow and the immune system. Today, FeLV is less important as a deadly infectious agent as in the last 20 years prevalence has been decreasing in most countries. Copyright © 2011 Elsevier B.V. All rights reserved.

[Physiopathological mechanisms of abomasal Trichostrongylidae infections in small ruminants].

PubMed

Scala, A

2006-09-01

Abomasal Trichostrongylidae infections are still today an important cause of scarce performances in small ruminants, mainly when bred in extensive systems. Although morpho-biology, symptomatology, prophylaxis and therapy of these infections are well known, other, such as physiopathology, are less investigated. The aim of the present note is to review the more important physiopathogenetic mechanisms of abomasal Trichostrongylidae infections, with special emphasis to Haemonchus spp. and Teladorsagia spp. The parasitic anorexia due to the action of gastrin, the defects of digestion due to hypocloridia, the scarce intestinal absorption and anaemia caused by H. contortus are discussed. Furthermore, the effects of hypersensitivity sometimes caused by these abomasal nematodes are examined. A better knowledge of physiopathological mechanisms can represent an important factor to understand the relationships between host and parasite, useful to set up new diagnostic techniques or new therapeutic and prophylactic protocols for sanitary education and control plans of these important and widespread parasitic infections.

Transcriptional response of honey bee larvae infected with the bacterial pathogen Paenibacillus larvae

USDA-ARS?s Scientific Manuscript database

American foulbrood disease of honey bees is caused by the bacterium Paenibacillus larvae. Infection occurs per os in larvae and systemic infection requires a breaching of the host peritrophic matrix and midgut epithelium. Genetic variation exists for both bacterial virulence and host resistance, and...

Term Stillbirth Caused by Oral Fusobacterium nucleatum

PubMed Central

Han, Yiping W.; Fardini, Yann; Chen, Casey; Iacampo, Karla G.; Peraino, Victoria A.; Shamonki, Jaime M.; Redline, Raymond W.

2010-01-01

Background Intrauterine infection is a recognized cause of adverse pregnancy outcome but the source of infection is often undetermined. We report a case of stillbirth caused by Fusobacterium nucleatum that originated in the mother’s mouth. Case A woman with pregnancy-associated gingivitis experienced an upper respiratory tract infection at term, followed by stillbirth a few days later. Fusobacterium nucleatum was isolated from the placenta and the infant. Examination of different microbial flora from the mother identified the same clone in her subgingival plaque, but not in the supragingival plaque, vagina, or rectum. Conclusion F. nucleatum may have translocated from the mother’s mouth to the uterus when the immune system was weakened during the respiratory infection. This case sheds light on patient management for those with pregnancy-associated gingivitis. PMID:20093874

Implementing systems thinking for infection prevention: The cessation of repeated scabies outbreaks in a respiratory care ward.

PubMed

Chuang, Sheuwen; Howley, Peter P; Lin, Shih-Hua

2015-05-01

Root cause analysis (RCA) is often adopted to complement epidemiologic investigation for outbreaks and infection-related adverse events in hospitals; however, RCA has been argued to have limited effectiveness in preventing such events. We describe how an innovative systems analysis approach halted repeated scabies outbreaks, and highlight the importance of systems thinking for outbreaks analysis and sustaining effective infection prevention and control. Following RCA for a third successive outbreak of scabies over a 17-month period in a 60-bed respiratory care ward of a Taiwan hospital, a systems-oriented event analysis (SOEA) model was used to reanalyze the outbreak. Both approaches and the recommendations were compared. No nosocomial scabies have been reported for more than 1975 days since implementation of the SOEA. Previous intervals between seeming eradication and repeat outbreaks following RCA were 270 days and 180 days. Achieving a sustainable positive resolution relied on applying systems thinking and the holistic analysis of the system, not merely looking for root causes of events. To improve the effectiveness of outbreaks analysis and infection control, an emphasis on systems thinking is critical, along with a practical approach to ensure its effective implementation. The SOEA model provides the necessary framework and is a viable complementary approach, or alternative, to RCA. Copyright © 2015 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.

Sepsis

MedlinePlus

Septicemia; Sepsis syndrome; Systemic inflammatory response syndrome; SIRS; Septic shock ... The symptoms of sepsis are not caused by the germs themselves. Instead, chemicals the body releases cause the response. A bacterial infection anywhere ...

Risk and Protective Factors for Cause-Specific Mortality After Spinal Cord Injury.

PubMed

Krause, James S; Cao, Yue; DeVivo, Michael J; DiPiro, Nicole D

2016-10-01

To investigate the association of multiple sets of risk and protective factors (biographic and injury, socioeconomic, health) with cause-specific mortality after spinal cord injury (SCI). Retrospective analysis of a prospectively created cohort. Spinal Cord Injury Model Systems facilities. Adults (N=8157) with traumatic SCI who were enrolled in a model systems facility after 1973 and received follow-up evaluation that included all study covariates (between November 1, 1995 and October 31, 2006). Not applicable. All-cause mortality was determined using the Social Security Death Index as of January 1, 2014. Causes of death were obtained from the National Death Index and classified as infective and parasitic diseases, neoplasms, respiratory system diseases, heart and blood vessel diseases, external causes, and other causes. Competing risk analysis, with time-dependent covariates, was performed with hazard ratios (HRs) for each cause of death. The HRs for injury severity indicators were highest for deaths due to respiratory system diseases (highest HR for injury level C1-4, 4.84) and infective and parasitic diseases (highest HR for American Spinal Injury Association Impairment Scale grade A, 5.70). In contrast, injury level and American Spinal Injury Association Impairment Scale grade were relatively unrelated to death due to neoplasms and external causes. Of the socioeconomic indicators, education and income were significantly predictive of a number of causes of death. Pressure ulcers were the only 1 of 4 secondary health condition indicators consistently related to cause of death. Injury severity was related to mortality due to infective disease and respiratory complications, suggesting that those with the most severe SCI should be targeted for prevention of these causes. Socioeconomic and health factors were more broadly related to a number of causes of death. Intervention strategies that enhance socioeconomic status and health may also result in reduced mortality due to multiple causes. Copyright © 2016 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

Toscana meningoencephalitis: a comparison to other viral central nervous system infections

PubMed Central

Jaijakul, Siraya; Arias, Cesar A.; Hossein, Monir; Arduino, Roberto C.; Wootton, Susan H.; Hasbun, Rodrigo

2012-01-01

Background Toscana virus (TOSV) is an emerging pathogen causing central nervous system (CNS) infection in Mediterranean countries, mostly during summer season. Objectives To compare the clinical and laboratory characteristics of Toscana CNS infections to the most common viral pathogens seen in the United States. Study Design We performed a case series of patients with 41 TOSV infection and compared the clinical characteristics, laboratory findings, imaging results and clinical outcomes to the most commonly recognized viral causes of meningoencephalitis in the US (enterovirus (n=60), herpes simplex virus (n=48), and west nile virus (n=30) from our multi-center study of patients with aseptic meningoencephalitis syndromes in the Greater Houston area. Results TOSV infection occurs in different age groups compared to enterovirus, HSV, and WNV. All infections most frequently occur during summer-fall except HSV which distributes throughout the year. All patients with TOSV had history of travel to endemic areas. There are differences in clinical presentation and CSF findings comparing TOSV and enterovirus, HSV, and WNV infection. There are no significant differences in outcomes of each infection except WNV meningoencephalitis which had a poorer outcome compared to TOSV infection. Conclusions TOSV is an emerging pathogen that should be considered in the differential diagnosis of patients with CNS infections and a recent travel history to endemic areas. PMID:22867730

Does the Intestinal Parasite Enterobius vermicularis Cause Acute Appendicitis?

PubMed

Pirhan, Yavuz; Özen, Fatma Zeynep; Kılınç, Çetin; Güçkan, Rıdvan

2017-06-01

Although intestinal parasitic infections rarely cause acute appendicitis, they are common public health problems in undeveloped and developing countries. Parasitic infections should be kept in mind in patients clinically suspected of having acute appendicitis, and treatment procedures should be adopted according to the etiology. Herein we presented the cases of four patients with clinical findings of acute appendicitis. Patients were clinically suspected of having acute appendicitis, and Enterobius vermicularis was detected in the pathological examinations of specimens. Pinworm infections are common parasitic infections that may mimic appendicitis. The pathology of the four cases was noted when the file of 186 patients aged between 4 and 72 years who underwent surgery for acute appendicitis in my hospital was retrospectively reviewed. When the appendectomy specimen was examined histopathologically it was understood that acute appendicitis was caused by Enterobius vermicularis parasite. In Enterobius infections, performing systemic therapy for patients and their family members is sufficient. To prevent unnecessary appendectomy, this type of infection should be made to ask in the history and clinical findings of patients.

Molecular pathology of emerging coronavirus infections

PubMed Central

Gralinski, Lisa E; Baric, Ralph S

2015-01-01

Respiratory viruses can cause a wide spectrum of pulmonary diseases, ranging from mild, upper respiratory tract infections to severe and life-threatening lower respiratory tract infections, including the development of acute lung injury (ALI) and acute respiratory distress syndrome (ARDS). Viral clearance and subsequent recovery from infection require activation of an effective host immune response; however, many immune effector cells may also cause injury to host tissues. Severe acute respiratory syndrome (SARS) coronavirus and Middle East respiratory syndrome (MERS) coronavirus cause severe infection of the lower respiratory tract, with 10% and 35% overall mortality rates, respectively; however, >50% mortality rates are seen in the aged and immunosuppressed populations. While these viruses are susceptible to interferon treatment in vitro, they both encode numerous genes that allow for successful evasion of the host immune system until after high virus titres have been achieved. In this review, we discuss the importance of the innate immune response and the development of lung pathology following human coronavirus infection. PMID:25270030

Evaluation of MALDI-TOF-MS for the Identification of Yeast Isolates Causing Bloodstream Infection.

PubMed

Turhan, Ozge; Ozhak-Baysan, Betil; Zaragoza, Oscar; Er, Halil; Sarıtas, Zubeyde Eres; Ongut, Gozde; Ogunc, Dilara; Colak, Dilek; Cuenca-Estrella, Manuel

2017-04-01

Infections due to Candida species are major causes of morbidity and mortality in humans, causing a diverse spectrum of clinical disease ranging from superficial and mucosal infections to invasive disease. Several authors have demonstrated that mortality is closely linked to both timing of therapy and/or source control. The rapid identification of pathogenic species is helpful to start timely and effective antifungal therapy. The aim of this study was to assess the performance of the matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) system for the correct and rapid identification of yeast isolates causing bloodstream infection. Between January 2014 and January 2015, a total of 117 yeast like organisms isolated from blood culture samples of 117 episodes from 102 patients who had blood stream infections were included in the study. The isolates were identified by MALDI-TOF MS. The results were compared with those obtained by the standard mycological methods and/or sequence analysis. One hundred and seventeen yeast isolates including 115 Candida spp and two non-Candida yeasts were analysed. The Biotyper correctly identified 115 (98.3%) isolates to the genus level and 102 (87.2%) isolates to the species level using the manufacturer's recommended cutoff scores. The Bruker Biotyper is a rapid, easy, inexpensive, and highly reliable system for the identification of yeast isolates. Early identification with MALDI-TOF MS would save time for determination of antifungal susceptibility and proper treatment strategy. The expansion of the database of the library by addition of less common species will improve the performance of the system.

Emerging Viral Infections and Their Impact on the Global Burden of Neurological Disease.

PubMed

Muñoz, Laura S; Garcia, Maria A; Gordon-Lipkin, Eliza; Parra, Beatriz; Pardo, Carlos A

2018-04-01

Emerging viral infections of the nervous system represent a major global public health concern in the 21st century. They are caused primarily by RNA viruses and are mostly associated with acute or subacute encephalitis. The spectrum of associated central or peripheral nervous system disorders is broad, and results either from a direct viral effect or due to the host immune responses against the infection. Emerging viral infections impose substantial neurological morbidity and mortality, particularly in low- and middle-income regions. In the past five decades, vector-borne viruses primarily transmitted by arthropods, or arboviruses, have been responsible for epidemics with a high burden of neurological disease, like the 2015-2016 Zika virus epidemic in the Americas. Viruses that have become neurovirulent for humans after geographical expansion include West Nile, Dengue, and Zika viruses. Factors such as animal migration, disruption of ecological niches, and cross-species contact have caused old viruses to reappear and cause neurological disease, as is the case of Ebola virus. In addition to these biological challenges, current preventive strategies, vaccination, and diagnostic and therapeutic approaches remain limited. We review the clinical-virological features and global impact of the most relevant emerging viral infections of the nervous system as they are projected over the 21st century. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

PubMed Central

Lang, Jean-Yves

1983-01-01

Systemic lupus erythematosus (SLE) is a chronic inflammatory disease of the connective tissue, affecting many organs of the body. The cause of SLE remains unknown, but the results of recent immunologic research have enlighted the characteristics of this disease and have contributed to improve the prognosis over the years. The renal and central nervous system involvement, as well as infection, remain high in the list of mortality causes. The usual treatment includes acetylsalicylic acid (ASA), antimalarials and corticosteroids. Main factors known to induce SLE are: sun exposures, pregnancy, therapeutic abortion, infection and several drugs. PMID:21283476

An evaluation of the wilt-causing bacterium Ralstonia solanacearum as a potential biological control agent for the alien Kahili ginger (Hedychium gardnerianum) in Hawaiian forests

USGS Publications Warehouse

1999-01-01

Kahili ginger (Hedychium gardnerianum) is an invasive weed in tropical forests in Hawaii and elsewhere. Bacterial wilt caused by the ginger strain of Ralstonia(=Pseudomonas) solanacearum systemically infects edible ginger (Zingiber officinale) and ornamental gingers (Hedychium spp.), causing wilt in infected plants. The suitability of R. solanacearum as a biological control agent for kahili ginger was investigated by inoculating seedlings and rooted cuttings of native forest plants, ornamental ginger, and solanaceous species to confirm host specificity. Inoculation via stem injection or root wounding with a bacterial–water suspension was followed by observation for 8 weeks. Inoculations on H. gardnerianum were then carried out in ohia-lehua (Metrosideros polymorpha) wet forests of Hawaii Volcanoes National Park to determine the bacterium's efficacy in the field. No native forest or solanaceous species developed wilt or other symptoms during the study. The bacterium caused limited infection near the inoculation site on H. coronarium, Z. zerumbet, Heliconia latispatha, and Musa sapientum. However, infection did not become systemic in any of these species, and normal growth resumed following appearance of initial symptoms. All inoculated H. gardnerianum plants developed irreversible chlorosis and severe wilting 3–4 weeks following inoculation. Systemic infection also caused death and decay of rhizomes. Most plants were completely dead 16–20 weeks following inoculation. The destructiveness of the ginger strain of R. solanacearum to edible ginger has raised questions regarding its use for biological control. However, because locations of kahili ginger infestations are often remote, the risk of contaminating edible ginger plantings is unlikely. The ability of this bacterium to cause severe disease in H. gardnerianum in the field, together with its lack of virulence in other ginger species, contributes to its potential as a biological control agent.

Genome analysis of Listeria ivanovii strain G770 that caused a deadly aortic prosthesis infection

PubMed Central

Beye, M.; Gouriet, F.; Michelle, C.; Casalta, J.-P.; Habib, G.; Raoult, D.; Fournier, P.-E.

2016-01-01

We sequenced the genome of Listeria ivanovii strain G770, which caused a deadly infection of the thoracic aortic prosthesis of a 78-year-old man. The 2.9 Mb genome exhibited 21 specific genes among L. ivanovii strains, including five genes encoding a type I restriction modification system and one glycopeptide resistance gene. PMID:26933501

Association of Systemic Anaplastic Large Cell Lymphoma and Active Toxoplasmosis in a Child.

PubMed

Sayyahfar, Shirin; Karimi, Abdollah; Gharib, Atoosa; Fahimzad, Alireza

2015-08-01

Anaplastic large cell lymphoma is a subset of non-Hodgkin lymphoma and an unusual disease in children. Herein we have reported a 7- year- old girl with a large necrotic skin ulcer on the chest caused by systemic form of anaplastic large-cell lymphoma and simultaneous active toxoplasmosis diagnosed by PCR on lymph node specimen. There were few reports showing a role for toxoplasma infection to cause some malignancies such as lymphoma in adults. Based to our knowledge, this has been the first report of simultaneous systemic anaplastic large cell lymphoma and active toxoplasmosis, documented by positive PCR on tissue biopsy in a child. This case report has suggested more attention to the accompanying Toxoplasma gondii infection as a probable cause of some types of lymphomas.

Myxoma virus in the European rabbit: interactions between the virus and its susceptible host.

PubMed

Stanford, Marianne M; Werden, Steven J; McFadden, Grant

2007-01-01

Myxoma virus (MV) is a poxvirus that evolved in Sylvilagus lagomorphs, and is the causative agent of myxomatosis in European rabbits (Oryctolagus cuniculus). This virus is not a natural pathogen of O. cuniculus, yet is able to subvert the host rabbit immune system defenses and cause a highly lethal systemic infection. The interaction of MV proteins and the rabbit immune system has been an ideal model to help elucidate host/poxvirus interactions, and has led to a greater understanding of how other poxvirus pathogens are able to cause disease in their respective hosts. This review will examine how MV causes myxomatosis, by examining a selection of the identified immunomodulatory proteins that this virus expresses to subvert the immune and inflammatory pathways of infected rabbit hosts.

Central nervous system infection by Listeria monocytogenes in patients with systemic lupus erythematosus: analysis of 26 cases, including the report of a new case.

PubMed

Horta-Baas, Gabriel; Guerrero-Soto, Omar; Barile-Fabris, Leonor

2013-01-01

Infections in patients with systemic lupus erythematosus cause significant morbidity. Infection due to Listeria monocytogenes (LM) is considered an opportunistic disease, and has been published on rare occasions in patients with SLE. To review the presentation of listeria infections in the central nervous system (CNS) in SLE patients. We conducted a literature review, selecting cases with central nervous system infection and confirmation of LM infection through culture. Twenty six cases are described. The most common presentation was meningitis, with meningoencephalitis and brain abscesses being less frequent. The predisposing factors are: use of glucocorticoids, immunosuppressants, renal replacement therapy and the activity flares. CNS infection by listeria is rare and sometimes fatal. The atypical presentation may lead to a delay in diagnosis and appropriate treatment. L. monocytogenes should be included in the differential diagnosis of patients with SLE with neurological manifestations. Copyright © 2013 Elsevier España, S.L. All rights reserved.

Bacterial skin infections: management of common streptococcal and stapylococcal lesions.

PubMed

Witkowski, J A; Parish, L C

1982-10-01

Skin infection occurs in any age-group, sex, and race but is particularly common in children. It is usually minor, but may indicate underlying systemic disease or may lead to systemic infection. Streptococci and staphylococci are common causes. Group A beta-hemolytic streptococci account for the majority of streptococcal infections in man. Infection most often involves the lower extremities and produces spreading erythema and necrosis but little purulence. Staphylococcal infections most commonly involve the face, the hair follicles and eccrine sweat ducts being the initial sites. Lesions appear as bullae and pustules with a narrow rim of erythema. Intense cellulitis surrounding the lesions usually points to a virulent, penicillin-resistant strain of Staphylococcus. Treatment of both types of infection consists of cleansing with antibacterial agents, removal of crusts, application of warm compresses, and use of topical or systemic antibiotics, depending on the severity of the infection and the type of pyoderma involved.

Cryptococcus gattii infections in multiple states outside the US Pacific Northwest.

PubMed

Harris, Julie R; Lockhart, Shawn R; Sondermeyer, Gail; Vugia, Duc J; Crist, Matthew B; D'Angelo, Melissa Tobin; Sellers, Brenda; Franco-Paredes, Carlos; Makvandi, Monear; Smelser, Chad; Greene, John; Stanek, Danielle; Signs, Kimberly; Nett, Randall J; Chiller, Tom; Park, Benjamin J

2013-10-01

Clonal VGII subtypes (outbreak strains) of Cryptococcus gattii have caused an outbreak in the US Pacific Northwest since 2004. Outbreak-associated infections occur equally in male and female patients (median age 56 years) and usually cause pulmonary disease in persons with underlying medical conditions. Since 2009, a total of 25 C. gattii infections, 23 (92%) caused by non-outbreak strain C. gattii, have been reported from 8 non-Pacific Northwest states. Sixteen (64%) patients were previously healthy, and 21 (84%) were male; median age was 43 years (range 15-83 years). Ten patients who provided information reported no past-year travel to areas where C. gattii is known to be endemic. Nineteen (76%) patients had central nervous system infections; 6 (24%) died. C. gattii infection in persons without exposure to known disease-endemic areas suggests possible endemicity in the United States outside the outbreak-affected region; these infections appear to differ in clinical and demographic characteristics from outbreak-associated C. gattii. Clinicians outside the outbreak-affected areas should be aware of locally acquired C. gattii infection and its varied signs and symptoms.

Cryptococcus gattii Infections in Multiple States Outside the US Pacific Northwest

PubMed Central

Lockhart, Shawn R.; Sondermeyer, Gail; Vugia, Duc J.; Crist, Matthew B.; D’Angelo, Melissa Tobin; Sellers, Brenda; Franco-Paredes, Carlos; Makvandi, Monear; Smelser, Chad; Greene, John; Stanek, Danielle; Signs, Kimberly; Nett, Randall J.; Chiller, Tom; Park, Benjamin J.

2013-01-01

Clonal VGII subtypes (outbreak strains) of Cryptococcus gattii have caused an outbreak in the US Pacific Northwest since 2004. Outbreak-associated infections occur equally in male and female patients (median age 56 years) and usually cause pulmonary disease in persons with underlying medical conditions. Since 2009, a total of 25 C. gattii infections, 23 (92%) caused by non–outbreak strain C. gattii, have been reported from 8 non–Pacific Northwest states. Sixteen (64%) patients were previously healthy, and 21 (84%) were male; median age was 43 years (range 15–83 years). Ten patients who provided information reported no past-year travel to areas where C. gattii is known to be endemic. Nineteen (76%) patients had central nervous system infections; 6 (24%) died. C. gattii infection in persons without exposure to known disease-endemic areas suggests possible endemicity in the United States outside the outbreak-affected region; these infections appear to differ in clinical and demographic characteristics from outbreak-associated C. gattii. Clinicians outside the outbreak-affected areas should be aware of locally acquired C. gattii infection and its varied signs and symptoms. PMID:24050410

Acute dermal abscesses caused by Serratia marcescens.

PubMed

Soria, Xavier; Bielsa, Isabel; Ribera, Miquel; Herrero, María José; Domingo, Helena; Carrascosa, José Manuel; Ferrándiz, Carlos

2008-05-01

Primary acute cutaneous infections caused by Serratia marcescens are extremely unusual. Nevertheless, Serratia infections are especially frequent in chronic granulomatous disease, which is a primary immunodeficiency that affects phagocytic cells of the innate immune system. We report a young man without history of infections, who developed multiple dermal abscesses on a leg with chronic lymphoedema attributed to S marcescens. Laboratory investigations showed a delayed partial neutrophilic oxidative function. It is remarkable that the patient did not have any other infections during childhood, when most of the innate immune deficiencies are diagnosed, and he had no history of granulomatous lesions. We hypothesize that the delayed neutrophilic oxidative function could be explained by a partial neutrophilic oxidative function, which could be enough to maintain the patient asymptomatic until this infection.

Virology, Immunology, and Clinical Course of HIV Infection.

ERIC Educational Resources Information Center

McCutchan, J. Allen

1990-01-01

Presents overview of medical aspects of human immunodeficiency virus Type 1 (HIV-1) disease. Addresses structure and replication of virus, current methods for detecting HIV-1 in infected persons, effects of the virus on immune system, and clinical course of HIV-1 disease. Emphasizes variable causes of progression through HIV-1 infection stages;…

West Nile virus: immunity and pathogenesis.

PubMed

Lim, Stephanie M; Koraka, Penelope; Osterhaus, Albert D M E; Martina, Byron E E

2011-06-01

West Nile virus (WNV) is a neurotropic, arthropod-borne flavivirus that is maintained in an enzootic cycle between mosquitoes and birds, but can also infect and cause disease in horses and humans. WNV is endemic in parts of Africa, Europe, the Middle East, and Asia, and since 1999 has spread to North America, Mexico, South America, and the Caribbean. WNV infects the central nervous system (CNS) and can cause severe disease in a small minority of infected humans, mostly immunocompromised or the elderly. This review discusses some of the mechanisms by which the immune system can limit dissemination of WNV infection and elaborates on the mechanisms involved in pathogenesis. Reasons for susceptibility to WNV-associated neuroinvasive disease in less than 1% of cases remain unexplained, but one favored hypothesis is that the involvement of the CNS is associated with a weak immune response allowing robust WNV replication in the periphery and spread of the virus to the CNS.

Virus signaling and apoptosis in the central nervous system infection.

PubMed

Perkins, Dana

2005-09-01

Viruses target the central nervous system (CNS) incidentally, due to complications of systemic infection, or specifically, by ascending via the axons of peripheral and cranial nerves. In the CNS, viruses cause acute disease (viz. encephalitis), latent infections or neurodegenerative pathology. Causation of acute disease or immune-mediated pathology, and virus involvement in the etiology of chronic neurodegenerative diseases depends, at least in part, on the ability to commander signaling pathways. Better understanding of these virus-host cell interactions will help identify molecular targets for the development of improved therapeutic strategies.

Papillomaviruses: Viral evolution, cancer and evolutionary medicine.

PubMed

Bravo, Ignacio G; Félez-Sánchez, Marta

2015-01-28

Papillomaviruses (PVs) are a numerous family of small dsDNA viruses infecting virtually all mammals. PVs cause infections without triggering a strong immune response, and natural infection provides only limited protection against reinfection. Most PVs are part and parcel of the skin microbiota. In some cases, infections by certain PVs take diverse clinical presentations from highly productive self-limited warts to invasive cancers. We propose PVs as an excellent model system to study the evolutionary interactions between the immune system and pathogens causing chronic infections: genotypically, PVs are very diverse, with hundreds of different genotypes infecting skin and mucosa; phenotypically, they display extremely broad gradients and trade-offs between key phenotypic traits, namely productivity, immunogenicity, prevalence, oncogenicity and clinical presentation. Public health interventions have been launched to decrease the burden of PV-associated cancers, including massive vaccination against the most oncogenic human PVs, as well as systematic screening for PV chronic anogenital infections. Anti-PVs vaccines elicit protection against infection, induce cross-protection against closely related viruses and result in herd immunity. However, our knowledge on the ecological and intrapatient dynamics of PV infections remains fragmentary. We still need to understand how the novel anthropogenic selection pressures posed by vaccination and screening will affect viral circulation and epidemiology. We present here an overview of PV evolution and the connection between PV genotypes and the phenotypic, clinical manifestations of the diseases they cause. This differential link between viral evolution and the gradient cancer-warts-asymptomatic infections makes PVs a privileged playground for evolutionary medicine research. © The Author(s) 2015. Published by Oxford University Press on behalf of the Foundation for Evolution, Medicine, and Public Health.

A multicenter study of outcome in systemic lupus erythematosus. II. Causes of death.

PubMed

Rosner, S; Ginzler, E M; Diamond, H S; Weiner, M; Schlesinger, M; Fries, J F; Wasner, C; Medsger, T A; Ziegler, G; Klippel, J H; Hadler, N M; Albert, D A; Hess, E V; Spencer-Green, G; Grayzel, A; Worth, D; Hahn, B H; Barnett, E V

1982-06-01

Causes of death were examined for 1,103 systemic lupus erythematosus patients who were followed from 1965 to 1978 at 9 centers that participated in the Lupus Survival Study Group. A total of 222 patients (20%) died. Lupus-related organ system involvement (mainly active nephritis) and infection were the most frequent primary causes of death. Causes of death were similar throughout the followup period. Hemodialysis had little impact on the length of survival for patients with nephritis. Active central nervous system disease and myocardial infarction were infrequent causes of death. There were no deaths from malignancy.

Genetics of Host Response to Leishmania tropica in Mice – Different Control of Skin Pathology, Chemokine Reaction, and Invasion into Spleen and Liver

PubMed Central

Grekov, Igor; Volkova, Valeriya; Vojtíšková, Jarmila; Slapničková, Martina; Kurey, Iryna; Sohrabi, Yahya; Svobodová, Milena; Demant, Peter; Lipoldová, Marie

2012-01-01

Background Leishmaniasis is a disease caused by protozoan parasites of genus Leishmania. The frequent involvement of Leishmania tropica in human leishmaniasis has been recognized only recently. Similarly as L. major, L. tropica causes cutaneous leishmaniasis in humans, but can also visceralize and cause systemic illness. The relationship between the host genotype and disease manifestations is poorly understood because there were no suitable animal models. Methods We studied susceptibility to L. tropica, using BALB/c-c-STS/A (CcS/Dem) recombinant congenic (RC) strains, which differ greatly in susceptibility to L. major. Mice were infected with L. tropica and skin lesions, cytokine and chemokine levels in serum, and parasite numbers in organs were measured. Principal Findings Females of BALB/c and several RC strains developed skin lesions. In some strains parasites visceralized and were detected in spleen and liver. Importantly, the strain distribution pattern of symptoms caused by L. tropica was different from that observed after L. major infection. Moreover, sex differently influenced infection with L. tropica and L. major. L. major-infected males exhibited either higher or similar skin pathology as females, whereas L. tropica-infected females were more susceptible than males. The majority of L. tropica-infected strains exhibited increased levels of chemokines CCL2, CCL3 and CCL5. CcS-16 females, which developed the largest lesions, exhibited a unique systemic chemokine reaction, characterized by additional transient early peaks of CCL3 and CCL5, which were not present in CcS-16 males nor in any other strain. Conclusion Comparison of L. tropica and L. major infections indicates that the strain patterns of response are species-specific, with different sex effects and largely different host susceptibility genes. PMID:22679519

The potential of desferrioxamine-gallium as an anti-Pseudomonas therapeutic agent

PubMed Central

Banin, Ehud; Lozinski, Alina; Brady, Keith M.; Berenshtein, Eduard; Butterfield, Phillip W.; Moshe, Maya; Chevion, Mordechai; Greenberg, Everett Peter; Banin, Eyal

2008-01-01

The opportunistic pathogen Pseudomonas aeruginosa causes infections that are difficult to treat by antibiotic therapy. This bacterium can cause biofilm infections where it shows tolerance to antibiotics. Here we report the novel use of a metallo-complex, desferrioxamine-gallium (DFO-Ga) that targets P. aeruginosa iron metabolism. This complex kills free-living bacteria and blocks biofilm formation. A combination of DFO-Ga and the anti-Pseudomonas antibiotic gentamicin caused massive killing of P. aeruginosa cells in mature biofilms. In a P. aeruginosa rabbit corneal infection, topical administration of DFO-Ga together with gentamicin decreased both infiltrate and final scar size by about 50% compared to topical application of gentamicin alone. The use of DFO-Ga as a Trojan horse delivery system that interferes with iron metabolism shows promise as a treatment for P. aeruginosa infections. PMID:18931304

CXCR1-mediated Neutrophil Degranulation and Fungal Killing Promotes Candida Clearance and Host Survival

PubMed Central

Swamydas, Muthulekha; Gao, Ji-Liang; Break, Timothy J.; Johnson, Melissa D.; Jaeger, Martin; Rodriguez, Carlos A.; Lim, Jean K.; Green, Nathaniel M.; Collar, Amanda L.; Fischer, Brett G.; Lee, Chyi-Chia Richard; Perfect, John R.; Alexander, Barbara D.; Kullberg, Bart-Jan; Netea, Mihai G.; Murphy, Philip M.; Lionakis, Michail S.

2016-01-01

Systemic Candida albicans infection causes high morbidity and mortality and is now the leading cause of nosocomial bloodstream infection in the US. Neutropenia is a major risk factor for poor outcome in infected patients; however, the molecular factors that mediate neutrophil trafficking and effector function during infection are poorly defined. Here, using a mouse model of systemic candidiasis, we found that the neutrophil-selective CXC chemokine receptor Cxcr1 and its ligand, Cxcl5, are highly induced in the Candida-infected kidney, the target organ in the model. To investigate the role of Cxcr1 in antifungal host defense in vivo, we generated Cxcr1−/− mice and analyzed their immune response to Candida. Mice lacking Cxcr1 exhibited decreased survival with enhanced Candida growth in the kidney and renal failure. Surprisingly, increased susceptibility of Cxcr1−/− mice to systemic candidiasis was not due to impaired neutrophil trafficking from the blood into the infected kidney but was the result of defective killing of the fungus by neutrophils that exhibited a cell-intrinsic decrease in degranulation. In humans, the mutant CXCR1 allele CXCR1-T276 results in impaired neutrophil degranulation and fungal killing and was associated with increased risk of disseminated candidiasis in infected patients. Together, our data demonstrate a biological function for mouse Cxcr1 in vivo and indicate that CXCR1-dependent neutrophil effector function is a critical innate protective mechanism of fungal clearance and host survival in systemic candidiasis. PMID:26791948

Combination liposomal amphotericin B, posaconazole and oral amphotericin B for treatment of gastrointestinal Mucorales in an immunocompromised patient.

PubMed

Anderson, Anthony; McManus, Dayna; Perreault, Sarah; Lo, Ying-Chun; Seropian, Stuart; Topal, Jeffrey E

2017-09-01

Mucormycosis is a life threatening infection caused by fungi in the order Mucorales. Mucormycosis can affect any organ system with rhino-orbital-cerebral and pulmonary infections being the most predominant infection types. Gastrointestinal mucormycosis is rare and accounts for only 4-7% of all cases. Here, we present a case of invasive gastrointestinal mucormycosis in an immunocompromised host treated with systemic and topical anti-mold therapy.

Development of protective immunity to Salmonella, a mucosal pathogen with a systemic agenda

PubMed Central

Griffin, Amanda J.; McSorley, Stephen J.

2014-01-01

Salmonella infections can cause a range of intestinal and systemic disease in human and animal hosts. While some Salmonella serovars initiate a localized intestinal inflammatory response, others use the intestine as a portal of entry to initiate a systemic infection. Considerable progress has been made in understanding bacterial invasion and dissemination strategies and the nature of the Salmonella-specific immune response to oral infection. Innate and adaptive immunity are rapidly initiated after oral infection but these effector responses can also be hindered by bacterial evasion strategies. Furthermore, although Salmonella resides within intramacrophage phagosomes, recent studies highlight a surprising collaboration of CD4 Th1, Th17, and B cell responses in mediating resistance to Salmonella infection. PMID:21307847

Comparative virulence and genomic analysis of 10 strains of Haemophilus parasuis

USDA-ARS?s Scientific Manuscript database

Haemophilus parasuis is the cause of Glasser's disease in swine, which is characterized by systemic infection resulting in polyserositis, meningitis, and arthritis. An enormous difference exists in the severity of disease caused by H. parasuis strains, ranging from lethal systemic disease to asympto...

Production of recombinant gG-1 protein of herpes simplex virus type 1 in a prokaryotic system in order to develop a type-specific enzyme-linked immunosorbent assay kit.

PubMed

Zandi, Keivan; Roostaee, Mohammad Hassan; Sadeghizadeh, Majid; Rasaee, Mohammad Javad; Sajedi, Reza Hassan; Soleimanjahi, Hoorieh

2007-08-01

The herpes simplex viruses are important causes of disease worldwide. Herpes simplex virus type 1 (HSV-1) is the primary cause of oral-facial and pharyngeal infections and may cause herpetic whitlow, eye infections as well as severe and sometimes dangerous infections of the eyes and brain. HSV-1 also accounts for 10-15% of all genital herpetic infections. Therefore, laboratory diagnosis of this virus and development of diagnostic serological techniques for HSV-1 is of particular importance. In the present study, pTrc His2A-gG1 plasmid, containing the full-length glycoprotein G (gG) protein, was produced in a prokaryotic system for the first time. Upon confirmation of a 37-kDa gG-1 protein production in a prokaryotic system based on western blotting and monoclonal antibodies, the protein was produced at a large scale and purified by ion-exchange chromatography using DEAE-sepharose. An HSV-1 type-specific diagnostic kit was designed and developed and the specificity and sensitivity of this kit were demonstrated to be 89.5% and 100%, respectively, as compared with a commercially available kit. A significant correlation was shown between the developed kit and the commercial kit.

Contribution of Human Lung Parenchyma and Leukocyte Influx to Oxidative Stress and Immune System-Mediated Pathology following Nipah Virus Infection.

PubMed

Escaffre, Olivier; Saito, Tais B; Juelich, Terry L; Ikegami, Tetsuro; Smith, Jennifer K; Perez, David D; Atkins, Colm; Levine, Corri B; Huante, Matthew B; Nusbaum, Rebecca J; Endsley, Janice J; Freiberg, Alexander N; Rockx, Barry

2017-08-01

Nipah virus (NiV) is a zoonotic emerging paramyxovirus that can cause fatal respiratory illness or encephalitis in humans. Despite many efforts, the molecular mechanisms of NiV-induced acute lung injury (ALI) remain unclear. We previously showed that NiV replicates to high titers in human lung grafts in NOD-SCID/γ mice, resulting in a robust inflammatory response. Interestingly, these mice can undergo human immune system reconstitution by the bone marrow, liver, and thymus (BLT) reconstitution method, in addition to lung tissue engraftment, giving altogether a realistic model to study human respiratory viral infections. Here, we characterized NiV Bangladesh strain (NiV-B) infection of human lung grafts from human immune system-reconstituted mice in order to identify the overall effect of immune cells on NiV pathogenesis of the lung. We show that NiV-B replicated to high titers in human lung grafts and caused similar cytopathic effects irrespective of the presence of human leukocytes in mice. However, the human immune system interfered with virus spread across lung grafts, responded to infection by leukocyte migration to small airways and alveoli of the lung grafts, and accelerated oxidative stress in lung grafts. In addition, the presence of human leukocytes increased the expression of cytokines and chemokines that regulate inflammatory influx to sites of infection and tissue damage. These results advance our understanding of how the immune system limits NiV dissemination and contributes to ALI and inform efforts to identify therapeutic targets. IMPORTANCE Nipah virus (NiV) is an emerging paramyxovirus that can cause a lethal respiratory and neurological disease in humans. Only limited data are available on NiV pathogenesis in the human lung, and the relative contribution of the innate immune response and NiV to acute lung injury (ALI) is still unknown. Using human lung grafts in a human immune system-reconstituted mouse model, we showed that the NiV Bangladesh strain induced cytopathic lesions in lung grafts similar to those described in patients irrespective of the donor origin or the presence of leukocytes. However, the human immune system interfered with virus spread, responded to infection by leukocyte infiltration in the small airways and alveolar area, induced oxidative stress, and triggered the production of cytokines and chemokines that regulate inflammatory influx by leukocytes in response to infection. Understanding how leukocytes interact with NiV and cause ALI in human lung xenografts is crucial for identifying therapeutic targets. Copyright © 2017 American Society for Microbiology.

Contribution of Human Lung Parenchyma and Leukocyte Influx to Oxidative Stress and Immune System-Mediated Pathology following Nipah Virus Infection

PubMed Central

Escaffre, Olivier; Saito, Tais B.; Juelich, Terry L.; Ikegami, Tetsuro; Smith, Jennifer K.; Perez, David D.; Atkins, Colm; Levine, Corri B.; Huante, Matthew B.; Nusbaum, Rebecca J.; Endsley, Janice J.

2017-01-01

ABSTRACT Nipah virus (NiV) is a zoonotic emerging paramyxovirus that can cause fatal respiratory illness or encephalitis in humans. Despite many efforts, the molecular mechanisms of NiV-induced acute lung injury (ALI) remain unclear. We previously showed that NiV replicates to high titers in human lung grafts in NOD-SCID/γ mice, resulting in a robust inflammatory response. Interestingly, these mice can undergo human immune system reconstitution by the bone marrow, liver, and thymus (BLT) reconstitution method, in addition to lung tissue engraftment, giving altogether a realistic model to study human respiratory viral infections. Here, we characterized NiV Bangladesh strain (NiV-B) infection of human lung grafts from human immune system-reconstituted mice in order to identify the overall effect of immune cells on NiV pathogenesis of the lung. We show that NiV-B replicated to high titers in human lung grafts and caused similar cytopathic effects irrespective of the presence of human leukocytes in mice. However, the human immune system interfered with virus spread across lung grafts, responded to infection by leukocyte migration to small airways and alveoli of the lung grafts, and accelerated oxidative stress in lung grafts. In addition, the presence of human leukocytes increased the expression of cytokines and chemokines that regulate inflammatory influx to sites of infection and tissue damage. These results advance our understanding of how the immune system limits NiV dissemination and contributes to ALI and inform efforts to identify therapeutic targets. IMPORTANCE Nipah virus (NiV) is an emerging paramyxovirus that can cause a lethal respiratory and neurological disease in humans. Only limited data are available on NiV pathogenesis in the human lung, and the relative contribution of the innate immune response and NiV to acute lung injury (ALI) is still unknown. Using human lung grafts in a human immune system-reconstituted mouse model, we showed that the NiV Bangladesh strain induced cytopathic lesions in lung grafts similar to those described in patients irrespective of the donor origin or the presence of leukocytes. However, the human immune system interfered with virus spread, responded to infection by leukocyte infiltration in the small airways and alveolar area, induced oxidative stress, and triggered the production of cytokines and chemokines that regulate inflammatory influx by leukocytes in response to infection. Understanding how leukocytes interact with NiV and cause ALI in human lung xenografts is crucial for identifying therapeutic targets. PMID:28539439

Incidence and clinical implication of nosocomial infections associated with implantable biomaterials – catheters, ventilator-associated pneumonia, urinary tract infections

PubMed Central

Guggenbichler, Josef Peter; Assadian, Ojan; Boeswald, Michael; Kramer, Axel

2012-01-01

Health care associated infections, the fourth leading cause of disease in industrialised countries, are a major health issue. One part of this condition is based on the increasing insertion and implantation of prosthetic medical devices, since presence of a foreign body significantly reduces the number of bacteria required to produce infection. The most significant hospital-acquired infections, based on frequency and potential severity, are those related to procedures e.g. surgical site infections and medical devices, including urinary tract infection in catheterized patients, pneumonia in patients intubated on a ventilator and bacteraemia related to intravascular catheter use. At least half of all cases of nosocomial infections are associated with medical devices. Modern medical and surgical practices have increasingly utilized implantable medical devices of various kinds. Such devices may be utilized only short-time or intermittently, for months, years or permanently. They improve the therapeutic outcome, save human lives and greatly enhance the quality of life of these patients. However, plastic devices are easily colonized with bacteria and fungi, able to be colonized by microorganisms at a rate of up to 0.5 cm per hour. A thick biofilm is formed within 24 hours on the entire surface of these plastic devices once inoculated even with a small initial number of bacteria. The aim of the present work is to review the current literature on causes, frequency and preventive measures against infections associated with intravascular devices, catheter-related urinary tract infection, ventilator-associated infection, and infections of other implantable medical devices. Raising awareness for infection associated with implanted medical devices, teaching and training skills of staff, and establishment of surveillance systems monitoring device-related infection seem to be the principal strategies used to achieve reduction and prevention of such infections. The intelligent use of suitable antiseptics in combination with medical devices may further support reduction and prevention of such infections. In addition to reducing the adverse clinical outcomes related with these infections, such reduction may substantially decrease the economic burden caused by device-related infection for health care systems. PMID:22242099

Reduction of Urinary Tract Infections Caused By Urethral Catheter through the Implementation of Hydrophobic Coating and Geometrical Modifications

NASA Astrophysics Data System (ADS)

Gare, Aya

2013-11-01

Catheter-Associated Urinary Tract Infection (CAUTI) is the most common nosocomial infection in the U.S. healthcare system. The obstruction of urine caused by confined air bubbles result in the development of urinary back-flow and stagnation, wherein microbial pathogens could multiply rapidly and colonization within catheters become commonplace. Infections can be prevented by aseptic insertion and the maintenance of a closed drainage system, keeping high infection control standards, and preventing back-flow from the catheter bag. The goal of this study is to assess the effectiveness of a simple, low cost, modification that may be implemented into current catheter designs to reduce the incidence of CAUTI. Using the principle of transmission of fluid-pressure and the Young-Laplace equation for capillary pressure difference, this research focuses on improving the liquid flow in the presence of confined bubbles to prevent stagnation and reflux of bacteria-ridden urine into the body. Preliminary experiments are performed on a variety of tubes with hydrophobic-coating the interior, as well as geometrically modifying the tubes. Proof-of-Concept Prototype tubes are used to represent the drainage system of the catheter structure.

Congenital brain infections.

PubMed

Arbelaez, Andres; Restrepo, Feliza; Davila, Jorge; Castillo, Mauricio

2014-06-01

Pediatric congenital intracranial infections are a group of different and important entities that constitute a small percentage of all pediatric infections. The causal factors and clinical presentations are different in children compared with adults. They require early recognition because delay diagnosis and initiation of treatment may have catastrophic consequences. Despite improvements in prenatal screening, vaccine safety, and antibiotics, infections of the central nervous system remain an important cause of neurological disabilities worldwide. This article reviews the most common congenital infections and their imaging findings.

Comparative studies of the genome, virulence, and protection of 10 Haemophilus parasuis strains

USDA-ARS?s Scientific Manuscript database

Haemophilus parasuis is the cause of Glässer’s disease in swine, which is characterized by systemic infection resulting in polyserositis, meningitis, and arthritis. An enormous difference exists in the severity of disease caused by H. parasuis strains, ranging from lethal systemic disease to asympto...

How (and why) the immune system makes us sleep

PubMed Central

Imeri, Luca; Opp, Mark R.

2010-01-01

Good sleep is necessary for physical and mental health. For example, sleep loss impairs immune function, and sleep is altered during infection. Immune signalling molecules are present in the healthy brain, where they interact with neurochemical systems to contribute to the regulation of normal sleep. Animal studies have shown that interactions between immune signalling molecules (such as the cytokine interleukin 1) and brain neurochemical systems (such as the serotonin system) are amplified during infection, indicating that these interactions might underlie the changes in sleep that occur during infection. Why should the immune system cause us to sleep differently when we are sick? We propose that the alterations in sleep architecture during infection are exquisitely tailored to support the generation of fever, which in turn imparts survival value. PMID:19209176

How (and why) the immune system makes us sleep.

PubMed

Imeri, Luca; Opp, Mark R

2009-03-01

Good sleep is necessary for physical and mental health. For example, sleep loss impairs immune function, and sleep is altered during infection. Immune signalling molecules are present in the healthy brain, where they interact with neurochemical systems to contribute to the regulation of normal sleep. Animal studies have shown that interactions between immune signalling molecules (such as the cytokine interleukin 1) and brain neurochemical systems (such as the serotonin system) are amplified during infection, indicating that these interactions might underlie the changes in sleep that occur during infection. Why should the immune system cause us to sleep differently when we are sick? We propose that the alterations in sleep architecture during infection are exquisitely tailored to support the generation of fever, which in turn imparts survival value.

Central venous catheter infection caused by Moraxella osloensis in a patient receiving home parenteral nutrition.

PubMed

Buchman, A L; Pickett, M J; Mann, L; Ament, M E

1993-01-01

We report the first case of a central venous catheter infection caused by Moraxella osloensis, which was successfully treated without catheter removal. The isolation, identification, and pathogenesis of this species are discussed. It is recommended that Moraxella isolates be identified to species in order to determine the relative pathogenic and opportunistic roles of the various Moraxella species. Our case also demonstrates that catheter sepsis caused by some Gram-negative organisms may be amenable to systemic antibiotic therapy without the necessity of catheter removal.

Prolonged protection against Intranasal challenge with influenza virus following systemic immunization or combinations of mucosal and systemic immunizations with a heat-labile toxin mutant.

PubMed

Zhou, Fengmin; Goodsell, Amanda; Uematsu, Yasushi; Vajdy, Michael

2009-04-01

Seasonal influenza virus infections cause considerable morbidity and mortality in the world, and there is a serious threat of a pandemic influenza with the potential to cause millions of deaths. Therefore, practical influenza vaccines and vaccination strategies that can confer protection against intranasal infection with influenza viruses are needed. In this study, we demonstrate that using LTK63, a nontoxic mutant of the heat-labile toxin from Escherichia coli, as an adjuvant for both mucosal and systemic immunizations, systemic (intramuscular) immunization or combinations of mucosal (intranasal) and intramuscular immunizations protected mice against intranasal challenge with a lethal dose of live influenza virus at 3.5 months after the second immunization.

Enterobacter aerogenes Needle Stick Leads to Improved Biological Management System

DOE Office of Scientific and Technical Information (OSTI.GOV)

Johanson, Richard E.

2004-08-01

A laboratory worker who received a needle stick from a contaminated needle while working with a culture containing Enterobactor aerogenes developed a laboratory acquired infection. Although this organism has been shown to cause community and nosocomial infections, there have been no documented cases of a laboratory acquired infections. Lessons learned from the event led to corrective actions which included modification of lab procedures, development of a biological inventory tracking and risk identification system and the establishment of an effective biological safety program.

Tick-borne infectious diseases in Australia.

PubMed

Graves, Stephen R; Stenos, John

2017-04-17

Tick bites in Australia can lead to a variety of illnesses in patients. These include infection, allergies, paralysis, autoimmune disease, post-infection fatigue and Australian multisystem disorder. Rickettsial (Rickettsia spp.) infections (Queensland tick typhus, Flinders Island spotted fever and Australian spotted fever) and Q fever (Coxiella burnetii) are the only systemic bacterial infections that are known to be transmitted by tick bites in Australia. Three species of local ticks transmit bacterial infection following a tick bite: the paralysis tick (Ixodes holocyclus) is endemic on the east coast of Australia and causes Queensland tick typhus due to R. australis and Q fever due to C. burnetii; the ornate kangaroo tick (Amblyomma triguttatum) occurs throughout much of northern, central and western Australia and causes Q fever; and the southern reptile tick (Bothriocroton hydrosauri) is found mainly in south-eastern Australia and causes Flinders Island spotted fever due to R. honei. Much about Australian ticks and the medical outcomes following tick bites remains unknown. Further research is required to increase understanding of these areas.

Epidemiological perspective on infections in chronic dialysis patients.

PubMed

Bloembergen, W E; Port, F K

1996-07-01

Infectious complications are a source of substantial morbidity and a common cause of death among dialysis patients. This article considers the magnitude and impact of the problem of infection among patients treated with hemodialysis (HD) and peritoneal dialysis (PD) using data from national registries and large cohort studies of patients with end-stage renal disease (ESRD). United States Renal Data System (USRDS) data indicate that in the United States for years 1991 to 1992, infection accounted for 12% of all deaths among HD patients and 15% of all deaths among PD patients. Septicemia was the underlying cause in 76% of these infectious deaths among HD patients, of which the vascular access, peritonitis, peripheral vascular disease, and other causes accounted for 12%, 5%, 24%, and 59% respectively. Among PD patients, septicemia accounted for 79% of infectious deaths. Of these deaths attributable to septicemia, peritonitis, peripheral vascular disease, and other causes were reported as the cause in 35%, 23%, and 41% respectively. Infection is also a major cause of morbidity in the dialysis population. Among HD patients, an average of 7.6 bacteremic episodes per 100 patient years (0.076 per year) has been described, of which 48% were associated with access infections. Among PD patients, studies have reported peritonitis rates ranging from 1 in 7.6 to 21.5 months (0.56 to 1.58 per patient year) and exit and/or tunnel infections occurring at a rate of 0.6 episodes per year. The known predictors of infectious complications among these populations are reviewed.

Co-infection with Influenza Viruses and Influenza-Like Virus During the 2015/2016 Epidemic Season.

PubMed

Szymański, K; Cieślak, K; Kowalczyk, D; Brydak, L B

2017-01-01

Concerning viral infection of the respiratory system, a single virus can cause a variety of clinical symptoms and the same set of symptoms can be caused by different viruses. Moreover, infection is often caused by a combination of viruses acting at the same time. The present study demonstrates, using multiplex RT-PCR and real-time qRT-PCR, that in the 2015/2016 influenza season, co-infections were confirmed in patients aged 1 month to 90 years. We found 73 co-infections involving influenza viruses, 17 involving influenza viruses and influenza-like viruses, and six involving influenza-like viruses. The first type of co-infections above mentioned was the most common, amounting to 51 cases, with type A and B viruses occurring simultaneously. There also were four cases of co-infections with influenza virus A/H1N1/pdm09 and A/H1N1/ subtypes and two cases with A/H1N1/pdm09 and A/H3N2/ subtypes. The 2015/2016 epidemic season was characterized by a higher number of confirmed co-infections compared with the previous seasons. Infections by more than one respiratory virus were most often found in children and in individuals aged over 65.

Central nervous system infection with Staphylococcus intermedius secondary to retrobulbar abscessation in a dog.

PubMed

Oliver, James A C; Llabrés-Diaz, Francisco J; Gould, David J; Powell, Roger M

2009-01-01

In this report, we describe a case of retrobulbar abscessation in a dog that was initially diagnosed as masticatory myositis and treated with immunosuppressive doses of corticosteroids. Secondary bacterial infection of the central nervous system (CNS) occurred and was definitively diagnosed by the analysis and culture of the cerebrospinal fluid. This is the first time that retrobulbar infection has been definitively shown to result in secondary bacterial infection of the CNS in the dog and highlights the importance of ruling out infectious causes of retrobulbar disease before assuming and treating for an immune-mediated etiology.

[Multicenter investigation of bufavirus in the etiology of viral central nervous system infections of adults and children].

PubMed

Altay Koçak, Aylin; Öcal, Murat; Polat, Meltem; Kanık Yüksek, Saliha; Aktaş Tapısız, Anıl; Tezer, Hasan; Özkul, Aykut; Ergünay, Koray; Bozdayı, Gülendam; Ahmed, Kamruddin

2017-04-01

Bufavirus (BuV) is a newly-identified parvovirus in the family of Parvoviridae. Metagenomic analysis of fecal samples from children in Burkina Faso with acute diarrhea showed a highly divergent parvovirus, which was named bufavirus (BuV). The global distribution, epidemiology and genetic characteristics of BuVs infections are obscure. It was first discovered as an agent causing gastroenteritis but the association of BuV infections with various clinical presentations mostly remain to be explored. The aims of this study were to investigate probable impact of BuV in central nervous system infections in a region where it was previously reported to cause human infections and to detect enteroviruses (EV) which are reported as a cause of central nervous system infections in our country. The study was undertaken in three institutions in Ankara province, Central Anatolia, Turkey. Patients, clinically diagnosed with febrile disease and/or central nervous system infections of presumed viral etiology, were enrolled in the study with informed consent. Cerebrospinal fluid specimens were collected from 93 children attended to Gazi University Hospital and Dışkapı Yıldırım Beyazıt Hospital from October 2011-April 2015 and 33 adult patients, attended to Hacettepe University Hospital from June 2012 to March 2013. Clinical history and follow-up, physical examination and standard laboratory findings of the patients were recorded. Nucleic acid extraction was performed via commercially available spin-column assays and complementery DNA (cDNA) synthesis was performed by using commercially available cDNA synthesis kit with randomised hexamer primers. BuV detection was carried out by in house nested-polymerase chain reaction (PCR) utilized with previously-described primers. EV detection was carried out by in house PCR with pan-enterovirus primers. Seventy-four percent (93/126) and 26% (33/126) of the patients were children (0-18) and adults (19-86), respectively. In all patients, bacterial, mycobacterial and fungal cultures were negative, as well as PCR for herpes simplex virus (HSV) types 1 and 2. PCR results of all samples were negative for BuV and EV. This is the first study that evaluates a probable association of BuV and central nervous system infections. Although Parvovirus B19, a well-characterized human pathogen can rarely cause encephalitis, our findings did not confirm such an association for BuV in this preliminary investigation. However, long-term evaluation of individual cases with unknown etiology is required to reveal the relationship of the virus with specific environments.

Discovery of a lentivirus susceptibility gene in sheep

USDA-ARS?s Scientific Manuscript database

Ovine lentivirus targets the host immune system and causes persistent retroviral infections affecting millions of sheep worldwide. In primates, lentivirus resistance is attributed to mutant virus coreceptors that are not expressed. In sheep, some animals are resistant to lentivirus infection despit...

First fatal case of CNS infection caused by Enterovirus A in Brazil

PubMed Central

Oliveira, D.B.; Machado, G.; Almeida, G.M.F.; Ferreira, P.C.P.; Bonjardim, C.A.; de Souza Trindade, G.; Abrahão, J.S.; Kroon, E.G.

2015-01-01

We describe what is to our knowledge the first fatal case of central nervous system Enterovirus infection in Brazil. Molecular and phylogenetic characterization revealed that Enterovirus A was the aetiologic agent of this case. PMID:26442151

Human parasitic meningitis caused by Angiostrongylus cantonensis infection in Taiwan.

PubMed

Tsai, Hung-Chin; Chen, Yao-Shen; Yen, Chuan-Min

2013-06-01

The major cause of eosinophilic meningitis in Taiwan is Angiostrongylus cantonensis. Humans are infected by ingesting terrestrial and freshwater snails and slugs. In 1998 and 1999, two outbreaks of eosinophilic meningitis caused by A. cantonensis infection were reported among 17 adult male immigrant Thai laborers who had eaten raw golden apple snails (Pomacea canaliculata). Another outbreak associated with consuming a health drink consisting of raw vegetable juice was reported in 2001. These adult cases differed from reports in the 1970s and 1980s, in which most of the cases were in children. With improvements in public health and education of foreign laborers, there have since been only sporadic cases in Taiwan. Review of clinical research indicates inconsistent association of Magnetic Resonance Imaging (MRI) results with clinical features of eosinophilic meningitis. MRI features were nonspecific but there was an association between the presence of high brain MRI signal intensities and severity of peripheral and cerebrospinal fluid (CSF) eosinophilia. Inflammatory markers have been identified in the CSF of patients with eosinophilic meningitis caused by A. cantonensis infection, and vascular endothelial growth factor (VEGF), hepatocyte growth factor (HGF), and the matrix metalloproteinase system may be associated with blood-brain barrier disruption. Eosinophilic meningitis caused by A. cantonensis infection is not a reportable disease in Taiwan. It is important that a public advisory and education program be developed to reduce future accidental infection.

How Do the Virulence Factors of Shigella Work Together to Cause Disease?

PubMed

Mattock, Emily; Blocker, Ariel J

2017-01-01

Shigella is the major cause of bacillary dysentery world-wide. It is divided into four species, named S. flexneri, S. sonnei, S. dysenteriae , and S. boydii , which are distinct genomically and in their ability to cause disease. Shigellosis, the clinical presentation of Shigella infection, is characterized by watery diarrhea, abdominal cramps, and fever. Shigella 's ability to cause disease has been attributed to virulence factors, which are encoded on chromosomal pathogenicity islands and the virulence plasmid. However, information on these virulence factors is not often brought together to create a detailed picture of infection, and how this translates into shigellosis symptoms. Firstly, Shigella secretes virulence factors that induce severe inflammation and mediate enterotoxic effects on the colon, producing the classic watery diarrhea seen early in infection. Secondly, Shigella injects virulence effectors into epithelial cells via its Type III Secretion System to subvert the host cell structure and function. This allows invasion of epithelial cells, establishing a replicative niche, and causes erratic destruction of the colonic epithelium. Thirdly, Shigella produces effectors to down-regulate inflammation and the innate immune response. This promotes infection and limits the adaptive immune response, causing the host to remain partially susceptible to re-infection. Combinations of these virulence factors may contribute to the different symptoms and infection capabilities of the diverse Shigella species, in addition to distinct transmission patterns. Further investigation of the dominant species causing disease, using whole-genome sequencing and genotyping, will allow comparison and identification of crucial virulence factors and may contribute to the production of a pan- Shigella vaccine.

How Do the Virulence Factors of Shigella Work Together to Cause Disease?

PubMed Central

Mattock, Emily; Blocker, Ariel J.

2017-01-01

Shigella is the major cause of bacillary dysentery world-wide. It is divided into four species, named S. flexneri, S. sonnei, S. dysenteriae, and S. boydii, which are distinct genomically and in their ability to cause disease. Shigellosis, the clinical presentation of Shigella infection, is characterized by watery diarrhea, abdominal cramps, and fever. Shigella's ability to cause disease has been attributed to virulence factors, which are encoded on chromosomal pathogenicity islands and the virulence plasmid. However, information on these virulence factors is not often brought together to create a detailed picture of infection, and how this translates into shigellosis symptoms. Firstly, Shigella secretes virulence factors that induce severe inflammation and mediate enterotoxic effects on the colon, producing the classic watery diarrhea seen early in infection. Secondly, Shigella injects virulence effectors into epithelial cells via its Type III Secretion System to subvert the host cell structure and function. This allows invasion of epithelial cells, establishing a replicative niche, and causes erratic destruction of the colonic epithelium. Thirdly, Shigella produces effectors to down-regulate inflammation and the innate immune response. This promotes infection and limits the adaptive immune response, causing the host to remain partially susceptible to re-infection. Combinations of these virulence factors may contribute to the different symptoms and infection capabilities of the diverse Shigella species, in addition to distinct transmission patterns. Further investigation of the dominant species causing disease, using whole-genome sequencing and genotyping, will allow comparison and identification of crucial virulence factors and may contribute to the production of a pan-Shigella vaccine. PMID:28393050

Acute pancreatitis caused by Mycoplasma pneumoniae: an unusual etiology.

PubMed

Valdés Lacasa, Teresa; Duarte Borges, María Alejandra; García Marín, Alicia; Gómez Cuervo, Covadonga

2017-06-01

It is well known that the most important etiologies of acute pancreatitis are gallstones and alcohol consumption. Once these causes have been ruled out, especially in young adults, it is important to consider less frequent etiologic factors such as drugs, trauma, malformations, autoimmunity or systemic diseases. Other rare and less well studied causes of this pathology are infections, among which Mycoplasma pneumoniae has been reported to cause acute pancreatitis as an unusual extrapulmonary manifestation. Here, we report the case of a 21-year-old patient who had acute idiopathic pancreatitis associated with an upper respiratory tract infection. After an in-depth study, all other causes of pancreatitis were ruled out and Mycoplasma was established as the clinical etiology.

A safe and efficient BCG vectored vaccine to prevent the disease caused by the human Respiratory Syncytial Virus.

PubMed

Rey-Jurado, Emma; Soto, Jorge; Gálvez, Nicolás; Kalergis, Alexis M

2017-09-02

The human Respiratory Syncytial Virus (hRSV) causes lower respiratory tract infections including pneumonia and bronchiolitis. Such infections also cause a large number of hospitalizations and affects mainly newborns, young children and the elderly worldwide. Symptoms associated with hRSV infection are due to an exacerbated immune response characterized by low levels of IFN-γ, recruitment of neutrophils and eosinophils to the site of infection and lung damage. Although hRSV is a major health problem, no vaccines are currently available. Different immunization approaches have been developed to achieve a vaccine that activates the immune system, without triggering an unbalanced inflammation. These approaches include live attenuated vaccine, DNA or proteins technologies, and the use of vectors to express proteins of the virus. In this review, we discuss the host immune response to hRSV and the immunological mechanisms underlying an effective and safe BCG vectored vaccine against hRSV.

Powassan encephalitis and Colorado tick fever.

PubMed

Romero, José R; Simonsen, Kari A

2008-09-01

This article discusses two tick-borne illnesses: Powassan encephalitis, a rare cause of central nervous system infection caused by the Powassan virus, and Colorado tick fever, an acute febrile illness caused by the Colorado tick fever virus common to the Rocky Mountain region of North America.

Meningitis caused by Oerskovia xanthineolytica.

PubMed

Kailath, E J; Goldstein, E; Wagner, F H

1988-03-01

In summary, we describe a case of central nervous system infection with O. xanthineolytica in which the infecting microbe probably was engrafted on a ventricular shunt. The bacteria caused a smoldering meningitis that did not respond to penicillin and rifampin despite in vitro sensitivity, presumably because of inadequate cerebrospinal fluid penetration of the penicillin and the recognized difficulty of eradicating bacteria from contaminated shunts. Removal of the shunt and continued treatment with penicillin and rifampin resulted in cure.

Systemic Epstein-Barr virus infection associated with membranous nephropathy in children.

PubMed

Araya, C E; González-Peralta, R P; Skoda-Smith, S; Dharnidharka, V R

2006-03-01

Epstein-Barr virus (EBV) infection can cause diverse renal manifestations ranging from microscopic hematuria to acute renal failure. Membranous nephropathy (MN) is an uncommon and usually secondary cause of nephrotic syndrome in children, and has been reported after chronic infections and antigenemia. We report two pediatric cases of secondary MN associated with acute and chronic systemic EBV infection. Patient 1 had a liver transplant for cirrhosis due to biliary atresia and developed chronic EB viremia. Membranous nephropathy occurred 3 years later and with aggressive therapy has partially subsided, in temporal association with a drop in blood EBV PCR levels. The other patient had a primary immunodeficiency and developed a lymphoproliferative disorder attributed to EBV. Nephrotic syndrome developed at initial presentation and was associated with MN on biopsy. The patient cleared the virus from blood, which was associated with eventual resolution of the MN. We postulate that EB viremia in patients lacking a fully competent immune system, but without a renal allograft, may create a susceptible environment for chronic systemic EB antigenemia that can then lead to immune-complex MN in the kidney. The association of EBV with renal histological changes consistent with MN has been suggested but not directly described before.

The Anopheles innate immune system in the defense against malaria infection

PubMed Central

Clayton, April M.; Dong, Yuemei; Dimopoulos, George

2014-01-01

The multifaceted innate immune system of insects is capable of fighting infection by a variety of pathogens including those causing human malaria. Malaria transmission by the Anopheles mosquito depends on the Plasmodium parasite’s successful completion of its lifecycle in the insect vector, a process that involves interactions with several tissues and cell types as well as with the mosquito’s innate immune system. This review will discuss our current understanding of the Anopheles mosquito’s innate immune responses against the malaria parasite Plasmodium and the influence of the insect’s intestinal microbiota on parasite infection. PMID:23988482

Hospitalization in daily home hemodialysis and matched thrice-weekly in-center hemodialysis patients.

PubMed

Weinhandl, Eric D; Nieman, Kimberly M; Gilbertson, David T; Collins, Allan J

2015-01-01

Cardiovascular disease is a common cause of hospitalization in dialysis patients. Daily hemodialysis improves some parameters of cardiovascular function, but whether it associates with lower hospitalization risk is unclear. Observational cohort study using US Renal Data System data. Medicare-enrolled daily (5 or 6 sessions weekly) home hemodialysis (HHD) patients initiating NxStage System One use from January 1, 2006, through December 31, 2009, and contemporary thrice-weekly in-center hemodialysis patients, matched 5 to 1. Daily HHD or thrice-weekly in-center hemodialysis. All-cause and cause-specific hospital admissions, hospital readmissions, and hospital days assessed from Medicare Part A claims. For 3,480 daily HHD and 17,400 thrice-weekly in-center hemodialysis patients in intention-to-treat analysis, the HR of all-cause admission for daily HHD versus in-center hemodialysis was 1.01 (95%CI, 0.98-1.03). Cause-specific admission HRs were 0.89 (95%CI, 0.86-0.93) for cardiovascular disease, 1.18 (95%CI, 1.13-1.23) for infection, 1.01 (95%CI, 0.93-1.09) for vascular access dysfunction, and 1.02 (95%CI, 0.99-1.06) for other morbidity. Regarding cardiovascular disease, first admission and readmission HRs for daily HHD versus in-center hemodialysis were 0.91 and 0.87, respectively. Regarding infection, first admission and readmission HRs were 1.35 and 1.03, respectively. Protective associations of daily HHD with heart failure and hypertensive disease were most pronounced, as were adverse associations of daily HHD with bacteremia/sepsis, cardiac infection, osteomyelitis, and vascular access infection. Results may be confounded by unmeasured factors, including vascular access type; information about dialysis frequency, duration, and dose was lacking; causes of admission may be misclassified; results may not apply to patients without Medicare coverage. All-cause hospitalization risk was similar in daily HHD and thrice-weekly in-center hemodialysis patients. However, risk of cardiovascular-related admission was lower with daily HHD, and risk of infection-related admission was higher. More attention should be afforded to infection in HHD patients. Copyright © 2014 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.

Acute encephalitis in the immunocompromised individual.

PubMed

Saylor, Deanna; Thakur, Kiran; Venkatesan, Arun

2015-08-01

This article describes recent advances in the diagnosis and management of encephalitis in immunocompromised individuals. Herpes simplex virus (HSV) and varicella zoster virus (VZV) are common causes of encephalitis in immunocompromised individuals, although clinical manifestations may be atypical, and thus challenging to recognize. Recently, an increased incidence of HSV and VZV central nervous system infections has been reported in association with novel immunosuppressive and immunomodulatory treatments. The free-living ameba Balamuthia mandrillaris causes granulomatous encephalitis predominantly in immunocompromised individuals and is associated with nearly uniform fatality. In the setting of organ transplantation, the recipient's immunocompromised state along with the potential for donor-transmitted infections can result in a unique epidemiology of encephalitis, including infection by human herpes virus-6 and BK virus. Recent studies utilizing next-generation sequencing techniques have identified several pathogens, including Leptospira santarosai and a neurotropic astrovirus, as causes of encephalitis in immunocompromised individuals. Diagnosis and management of encephalitis is challenging in immunocompromised individuals, in part because of atypical clinical presentations and the presence of uncommon or novel infectious agents. Unbiased techniques for pathogen discovery are likely to play an increasing role in the diagnosis of central nervous system infections in immunocompromised individuals.

IDENTIFICATION AND CHARACTERIZATION OF AEROMONAS ISOLATES FROM DRINKING WATER DISTRIBUTION SYSTEMS

EPA Science Inventory

Members of the bacterial genus Aeromonas are commonly isolated from both fresh and salt waters worldwide and some are believed to cause infections in humans, including gastroenteritis and wound infections. Currently, aeromonads are on the United States Environmental Protection A...

Passive therapy with humanized anti-staphylococcal enterotoxin B antibodies attenuates systemic inflammatory response and protects from lethal pneumonia caused by staphylococcal enterotoxin B-producing Staphylococcus aureus.

PubMed

Karau, Melissa J; Tilahun, Mulualem E; Krogman, Ashton; Osborne, Barbara A; Goldsby, Richard A; David, Chella S; Mandrekar, Jayawant N; Patel, Robin; Rajagopalan, Govindarajan

2017-10-03

Drugs such as linezolid that inhibit bacterial protein synthesis may be beneficial in treating infections caused by toxigenic Staphylococcus aureus. As protein synthesis inhibitors have no effect on preformed toxins, neutralization of pathogenic exotoxins with anti-toxin antibodies may be beneficial in conjunction with antibacterial therapy. Herein, we evaluated the efficacy of human-mouse chimeric high-affinity neutralizing anti-staphylococcal enterotoxin B (SEB) antibodies in the treatment of experimental pneumonia caused by SEB-producing S. aureus. Since HLA class II transgenic mice mount a stronger systemic immune response following challenge with SEB and are more susceptible to SEB-induced lethal toxic shock than conventional mice strains, HLA-DR3 transgenic mice were used. Lethal pneumonia caused by SEB-producing S. aureus in HLA-DR3 transgenic mice was characterized by robust T cell activation and elevated systemic levels of several pro-inflammatory cytokines and chemokines. Prophylactic administration of a single dose of linezolid 30 min prior to the onset of infection attenuated the systemic inflammatory response and protected from mortality whereas linezolid administered 60 min after the onset of infection failed to confer significant protection. Human-mouse chimeric high-affinity neutralizing anti-SEB antibodies alone, but not polyclonal human IgG, mitigated this response and protected from death when administered immediately after initiation of infection. Further, anti-SEB antibodies as well as intact polyclonal human IgG, but not its Fab or Fc fragments, protected from lethal pneumonia when followed with linezolid therapy 60 min later. In conclusion, neutralization of superantigens with high-affinity antibodies may have beneficial effects in pneumonia.

Completeness of Methicillin-Resistant Staphylococcus aureus Bloodstream Infection Reporting From Outpatient Hemodialysis Facilities to the National Healthcare Safety Network, 2013.

PubMed

Nguyen, Duc B; See, Isaac; Gualandi, Nicole; Shugart, Alicia; Lines, Christi; Bamberg, Wendy; Dumyati, Ghinwa; Harrison, Lee H; Lesher, Lindsey; Nadle, Joelle; Petit, Susan; Ray, Susan M; Schaffner, William; Townes, John; Njord, Levi; Sievert, Dawn; Thompson, Nicola D; Patel, Priti R

2016-02-01

Reports of bloodstream infections caused by methicillin-resistant Staphylococcus aureus among chronic hemodialysis patients to 2 Centers for Disease Control and Prevention surveillance systems (National Healthcare Safety Network Dialysis Event and Emerging Infections Program) were compared to evaluate completeness of reporting. Many methicillin-resistant S. aureus bloodstream infections identified in hospitals were not reported to National Healthcare Safety Network Dialysis Event.

Detection of Vaccinia virus in blood and faeces of experimentally infected cows.

PubMed

Guedes, M I M C; Rehfeld, I S; de Oliveira, T M L; Assis, F L; Matos, A C D; Abrahão, J S; Kroon, E G; Lobato, Z I P

2013-12-01

Bovine vaccinia (BV), a zoonosis caused by Vaccinia virus (VACV), affects dairy cattle and milkers, causing economic, veterinary and human health impacts. Despite such impacts, there are no experimental studies about the pathogenesis of BV in cows to assess whether there is a systemic spread of the virus and whether there are different ways of VACV shedding. Trying to answer some of these questions, a study was proposed using experimental inoculation of VACV in cows. All experimentally infected cows developed lesions compatible with VACV infection in cattle. Two of the six animals presented VACV DNA in blood and faecal samples, starting at the 2nd and the 3rd day post-infection (d.p.i.), respectively, and lasting until the 36th d.p.i., in an intermittent way. This study provides new evidence that VACV can be detected in blood and faeces of infected cows, suggesting that BV could be a systemic disease, and also bringing new information about the epidemiology and pathogenesis of BV. © 2012 Blackwell Verlag GmbH.

Approach to the patient with neutropenia in childhood

PubMed Central

Celkan, Tiraje; Koç, Begüm Şirin

2015-01-01

Neutrophils have an important role in host defense and acute inflammation. It is well known that susceptibility to infection increases when the neutrophil count is low. Neutropenia were classified as mild, moderate and severe according to the neutrophil counts, or acute and chronic depending on the duration of neutropenia, or congenital and acquired according to the mechanism. The patients with neutropenia are clinically different due to underlying mechanism, they have life- threatening infections or no infection may be observed. The most common cause of acquired neutropenia is viral infection, followed by drugs and autoimmune neutropenia. Congenital neutropenia are usually diagnosed by acute and life- threatening invasive bacterial and fungal infections. Immune system disorders and other systemic abnormalities may be accompanied or not. Recent years, novel single gen defects causing congenital neutropenia were defined through advanced genetic techniques. Molecular diagnosis is useful for risk stratification, choice of therapy and prognosis on follow- up. This review was prepared for pediatricians as a guide focused on approach neutropenia, which tests should be performed and when should be referred to a specialist. PMID:26568688

New clinical trial will test immunotherapy for type of HPV infection | Center for Cancer Research

Cancer.gov

Vulvar high-grade squamous intraepithelial lesion (HSIL) is caused by chronic infection with the human papillomavirus (HPV) type 16. Patients with vulvar HSIL have an increased risk of developing cancer. Lesions are usually treated surgically. However, the vulvar lesions commonly recur because of persistent systemic infection with HPV. Christian Hinrichs, M.D., a Lasker

Asymptomatic Hepadnaviral Persistence and Its Consequences in the Woodchuck Model of Occult Hepatitis B Virus Infection

PubMed Central

Mulrooney-Cousins, Patricia M.; Michalak, Tomasz I.

2015-01-01

Woodchuck hepatitis virus (WHV) is molecularly and pathogenically closely related to hepatitis B virus (HBV). Both viruses display tropism towards hepatocytes and cells of the immune system and cause similar liver pathology, where acute hepatitis can progress to chronic hepatitis and to hepatocellular carcinoma (HCC). Two forms of occult hepadnaviral persistence were identified in the woodchuck-WHV model: secondary occult infection (SOI) and primary occult infection (POI). SOI occurs after resolution of a serologically apparent infection with hepatitis or after subclinical serologically evident virus exposure. POI is caused by small amounts of virus and progresses without serological infection markers, but the virus genome and its replication are detectable in the immune system and with time in the liver. SOI can be accompanied by minimal hepatitis, while the hallmark of POI is normal liver morphology. Nonetheless, HCC develops in about 20% of animals with SOI or POI within 3 to 5 years. The virus persists throughout the lifespan in both SOI and POI at serum levels rarely greater than 100 copies/mL, causes hepatitis and HCC when concentrated and administered to virus-naïve woodchucks. SOI is accompanied by virus-specific T and B cell immune responses, while only virus-specific T cells are detected in POI. SOI coincides with protection against reinfection, while POI does not and hepatitis develops after challenge with liver pathogenic doses >1000 virions. Both SOI and POI are associated with virus DNA integration into the liver and the immune system genomes. Overall, SOI and POI are two distinct forms of silent hepadnaviral persistence that share common characteristics. Here, we review findings from the woodchuck model and discuss the relevant observations made in human occult HBV infection (OBI). PMID:26623268

Asymptomatic Hepadnaviral Persistence and Its Consequences in the Woodchuck Model of Occult Hepatitis B Virus Infection.

PubMed

Mulrooney-Cousins, Patricia M; Michalak, Tomasz I

2015-09-28

Woodchuck hepatitis virus (WHV) is molecularly and pathogenically closely related to hepatitis B virus (HBV). Both viruses display tropism towards hepatocytes and cells of the immune system and cause similar liver pathology, where acute hepatitis can progress to chronic hepatitis and to hepatocellular carcinoma (HCC). Two forms of occult hepadnaviral persistence were identified in the woodchuck-WHV model: secondary occult infection (SOI) and primary occult infection (POI). SOI occurs after resolution of a serologically apparent infection with hepatitis or after subclinical serologically evident virus exposure. POI is caused by small amounts of virus and progresses without serological infection markers, but the virus genome and its replication are detectable in the immune system and with time in the liver. SOI can be accompanied by minimal hepatitis, while the hallmark of POI is normal liver morphology. Nonetheless, HCC develops in about 20% of animals with SOI or POI within 3 to 5 years. The virus persists throughout the lifespan in both SOI and POI at serum levels rarely greater than 100 copies/mL, causes hepatitis and HCC when concentrated and administered to virus-naïve woodchucks. SOI is accompanied by virus-specific T and B cell immune responses, while only virus-specific T cells are detected in POI. SOI coincides with protection against reinfection, while POI does not and hepatitis develops after challenge with liver pathogenic doses >1000 virions. Both SOI and POI are associated with virus DNA integration into the liver and the immune system genomes. Overall, SOI and POI are two distinct forms of silent hepadnaviral persistence that share common characteristics. Here, we review findings from the woodchuck model and discuss the relevant observations made in human occult HBV infection (OBI).

In vitro and in vivo cell invasion and systemic spreading of Mycoplasma agalactiae in the sheep infection model

PubMed Central

Hegde, Shivanand; Hegde, Shrilakshmi; Spergser, Joachim; Brunthaler, René; Rosengarten, Renate; Chopra-Dewasthaly, Rohini

2014-01-01

Generally regarded as extracellular pathogens, molecular mechanisms of mycoplasma persistence, chronicity and disease spread are largely unknown. Mycoplasma agalactiae, an economically important pathogen of small ruminants, causes chronic infections that are difficult to eradicate. Animals continue to shed the agent for several months and even years after the initial infection, in spite of long antibiotic treatment. However, little is known about the strategies that M. agalactiae employs to survive and spread within an immunocompetent host to cause chronic disease. Here, we demonstrate for the first time its ability to invade cultured human (HeLa) and ruminant (BEND and BLF) host cells. Presence of intracellular mycoplasmas is clearly substantiated using differential immunofluorescence technique and quantitative gentamicin invasion assays. Internalized M. agalactiae could survive and exit the cells in a viable state to repopulate the extracellular environment after complete removal of extracellular bacteria with gentamicin. Furthermore, an experimental sheep intramammary infection was carried out to evaluate its systemic spread to organs and host niches distant from the site of initial infection. Positive results obtained via PCR, culture and immunohistochemistry, especially the latter depicting the presence of M. agalactiae in the cytoplasm of mammary duct epithelium and macrophages, clearly provide the first formal proof of M. agalactiae's capability to translocate across the mammary epithelium and systemically disseminate to distant inner organs. Altogether, the findings of these in vitro and in vivo studies indicate that M. agalactiae is capable of entering host cells and this might be the strategy that it employs at a population level to ward off the host immune response and antibiotic action, and to disseminate to new and safer niches to later egress and once again proliferate upon the return of favorable conditions to cause persistent chronic infections. PMID:25129554

A Role for Human Skin Mast Cells in Dengue Virus Infection and Systemic Spread.

PubMed

Troupin, Andrea; Shirley, Devon; Londono-Renteria, Berlin; Watson, Alan M; McHale, Cody; Hall, Alex; Hartstone-Rose, Adam; Klimstra, William B; Gomez, Gregorio; Colpitts, Tonya M

2016-12-01

Dengue virus (DENV) is a mosquito-borne flavivirus that causes serious global human disease and mortality. Skin immune cells are an important component of initial DENV infection and systemic spread. Here, we show that mast cells are a target of DENV in human skin and that DENV infection of skin mast cells induces degranulation and alters cytokine and growth factor expression profiles. Importantly, to our knowledge, we also demonstrate for the first time that DENV localizes within secretory granules in infected skin mast cells. In addition, DENV within extracellular granules was infectious in vitro and in vivo, trafficking through lymph to draining lymph nodes in mice. We demonstrate an important role for human skin mast cells in DENV infection and identify a novel mechanism for systemic spread of DENV infection from the initial peripheral mosquito injection site. Copyright © 2016 by The American Association of Immunologists, Inc.

Excessive Cytokine Response to Rapid Proliferation of Highly Pathogenic Avian Influenza Viruses Leads to Fatal Systemic Capillary Leakage in Chickens

PubMed Central

Kuribayashi, Saya; Sakoda, Yoshihiro; Kawasaki, Takeshi; Tanaka, Tomohisa; Yamamoto, Naoki; Okamatsu, Masatoshi; Isoda, Norikazu; Tsuda, Yoshimi; Sunden, Yuji; Umemura, Takashi; Nakajima, Noriko; Hasegawa, Hideki; Kida, Hiroshi

2013-01-01

Highly pathogenic avian influenza viruses (HPAIVs) cause lethal infection in chickens. Severe cases of HPAIV infections have been also reported in mammals, including humans. In both mammals and birds, the relationship between host cytokine response to the infection with HPAIVs and lethal outcome has not been well understood. In the present study, the highly pathogenic avian influenza viruses A/turkey/Italy/4580/1999 (H7N1) (Ty/Italy) and A/chicken/Netherlands/2586/2003 (H7N7) (Ck/NL) and the low pathogenic avian influenza virus (LPAIV) A/chicken/Ibaraki/1/2005 (H5N2) (Ck/Ibaraki) were intranasally inoculated into chickens. Ty/Italy replicated more extensively than Ck/NL in systemic tissues of the chickens, especially in the brain, and induced excessive mRNA expression of inflammatory and antiviral cytokines (IFN-γ, IL-1β, IL-6, and IFN-α) in proportion to its proliferation. Using in situ hybridization, IL-6 mRNA was detected mainly in microglial nodules in the brain of the chickens infected with Ty/Italy. Capillary leakage assessed by Evans blue staining was observed in multiple organs, especially in the brains of the chickens infected with Ty/Italy, and was not observed in those infected with Ck/NL. In contrast, LPAIV caused only local infection in the chickens, with neither apparent cytokine expression nor capillary leakage in any tissue of the chickens. The present results indicate that an excessive cytokine response is induced by rapid and extensive proliferation of HPAIV and causes fatal multiple organ failure in chickens. PMID:23874602

Molecular determinants of Pichinde virus infection of guinea pigs--a small animal model system for arenaviral hemorrhagic fevers.

PubMed

Liang, Yuying; Lan, Shuiyun; Ly, Hinh

2009-09-01

Arenaviruses are enveloped single-strand RNA viruses that mostly have natural hosts in rodents. Upon infection of humans, several arenaviruses can cause severe hemorrhagic fever diseases, including Lassa fever that is endemic in West Africa. The virulence mechanism of these deadly arenaviruses can be studied in a safe and economical small animal model-guinea pigs infected by a nonpathogenic arenavirus Pichinde virus (PICV), a virulent strain of which can cause similar disease syndromes in guinea pigs as arenaviral hemorrhagic fevers in humans. We have recently developed molecular clones for both the virulent and avirulent strains of PICV. Using the available reverse genetics tools, we are characterizing the molecular determinants of virulent arenavirus infections in vivo.

Redundant Function of Plasmacytoid and Conventional Dendritic Cells Is Required To Survive a Natural Virus Infection.

PubMed

Kaminsky, Lauren W; Sei, Janet J; Parekh, Nikhil J; Davies, Michael L; Reider, Irene E; Krouse, Tracy E; Norbury, Christopher C

2015-10-01

Viruses that spread systemically from a peripheral site of infection cause morbidity and mortality in the human population. Innate myeloid cells, including monocytes, macrophages, monocyte-derived dendritic cells (mo-DC), and dendritic cells (DC), respond early during viral infection to control viral replication, reducing virus spread from the peripheral site. Ectromelia virus (ECTV), an orthopoxvirus that naturally infects the mouse, spreads systemically from the peripheral site of infection and results in death of susceptible mice. While phagocytic cells have a requisite role in the response to ECTV, the requirement for individual myeloid cell populations during acute immune responses to peripheral viral infection is unclear. In this study, a variety of myeloid-specific depletion methods were used to dissect the roles of individual myeloid cell subsets in the survival of ECTV infection. We showed that DC are the primary producers of type I interferons (T1-IFN), requisite cytokines for survival, following ECTV infection. DC, but not macrophages, monocytes, or granulocytes, were required for control of the virus and survival of mice following ECTV infection. Depletion of either plasmacytoid DC (pDC) alone or the lymphoid-resident DC subset (CD8α(+) DC) alone did not confer lethal susceptibility to ECTV. However, the function of at least one of the pDC or CD8α(+) DC subsets is required for survival of ECTV infection, as mice depleted of both populations were susceptible to ECTV challenge. The presence of at least one of these DC subsets is sufficient for cytokine production that reduces ECTV replication and virus spread, facilitating survival following infection. Prior to the eradication of variola virus, the orthopoxvirus that causes smallpox, one-third of infected people succumbed to the disease. Following successful eradication of smallpox, vaccination rates with the smallpox vaccine have significantly dropped. There is now an increasing incidence of zoonotic orthopoxvirus infections for which there are no effective treatments. Moreover, the safety of the smallpox vaccine is of great concern, as complications may arise, resulting in morbidity. Like many viruses that cause significant human diseases, orthopoxviruses spread from a peripheral site of infection to become systemic. This study elucidates the early requirement for innate immune cells in controlling a peripheral infection with ECTV, the causative agent of mousepox. We report that there is redundancy in the function of two innate immune cell subsets in controlling virus spread early during infection. The viral control mediated by these cell subsets presents a potential target for therapies and rational vaccine design. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

Possible Zika Virus Infection Among Pregnant Women - United States and Territories, May 2016.

PubMed

Simeone, Regina M; Shapiro-Mendoza, Carrie K; Meaney-Delman, Dana; Petersen, Emily E; Galang, Romeo R; Oduyebo, Titilope; Rivera-Garcia, Brenda; Valencia-Prado, Miguel; Newsome, Kimberly B; Pérez-Padilla, Janice; Williams, Tonya R; Biggerstaff, Matthew; Jamieson, Denise J; Honein, Margaret A

2016-05-27

Zika virus is a cause of microcephaly and brain abnormalities (1), and it is the first known mosquito-borne infection to cause congenital anomalies in humans. The establishment of a comprehensive surveillance system to monitor pregnant women with Zika virus infection will provide data to further elucidate the full range of potential outcomes for fetuses and infants of mothers with asymptomatic and symptomatic Zika virus infection during pregnancy. In February 2016, Zika virus disease and congenital Zika virus infections became nationally notifiable conditions in the United States (2). Cases in pregnant women with laboratory evidence of Zika virus infection who have either 1) symptomatic infection or 2) asymptomatic infection with diagnosed complications of pregnancy can be reported as cases of Zika virus disease to ArboNET* (2), CDC's national arboviral diseases surveillance system. Under existing interim guidelines from the Council for State and Territorial Epidemiologists (CSTE), asymptomatic Zika virus infections in pregnant women who do not have known pregnancy complications are not reportable. ArboNET does not currently include pregnancy surveillance information (e.g., gestational age or pregnancy exposures) or pregnancy outcomes. To understand the full impact of infection on the fetus and neonate, other systems are needed for reporting and active monitoring of pregnant women with laboratory evidence of possible Zika virus infection during pregnancy. Thus, in collaboration with state, local, tribal, and territorial health departments, CDC established two surveillance systems to monitor pregnancies and congenital outcomes among women with laboratory evidence of Zika virus infection(†) in the United States and territories: 1) the U.S. Zika Pregnancy Registry (USZPR),(§) which monitors pregnant women residing in U.S. states and all U.S. territories except Puerto Rico, and 2) the Zika Active Pregnancy Surveillance System (ZAPSS), which monitors pregnant women residing in Puerto Rico. As of May 12, 2016, the surveillance systems were monitoring 157 and 122 pregnant women with laboratory evidence of possible Zika virus infection from participating U.S. states and territories, respectively. Tracking and monitoring clinical presentation of Zika virus infection, all prenatal testing, and adverse consequences of Zika virus infection during pregnancy are critical to better characterize the risk for congenital infection, the performance of prenatal diagnostic testing, and the spectrum of adverse congenital outcomes. These data will improve clinical guidance, inform counseling messages for pregnant women, and facilitate planning for clinical and public health services for affected families.

Aging leads to prolonged duration of inflammation-induced depression-like behavior caused by Bacillus Calmette-Guérin.

PubMed

Kelley, Keith W; O'Connor, Jason C; Lawson, Marcus A; Dantzer, Robert; Rodriguez-Zas, Sandra L; McCusker, Robert H

2013-08-01

Geriatric depression is a costly health issue, but little is known about its physiological underpinnings. Systemic inflammation sensitizes the innate immune system of aged animals and humans, but it is unknown if chronic, low-grade infections affect the duration of depressive-like behaviors. In this report, we infected adult (4-6 months) and aged (20-24 months) Balb/c mice with an attenuated strain of Mycobacterium bovis, Bacillus Calmette-Guérin (BCG), to induce a chronic infection. We then measured depression-like behaviors that have construct, face and predictive validity for human inflammation-associated clinical depression. Exposure to BCG caused acute sickness responses in both adult and aged mice. However, sickness behavior was prolonged in aged mice, as assessed by both locomotor and rearing activity. Two measures of depression-like behavior, which were tests involving sucrose preference and tail suspension, both showed that adult mice displayed depression-like behaviors at one day and seven days after exposure to BCG. However, aged mice continued to express both of these depression-like behaviors at three weeks following infection. Infection with BCG caused an increase in tryptophan catabolism, as evidenced by a significant rise in the plasma kynurenine/tryptophan ratio that peaked at 7 days post-infection. In aged mice, greater tryptophan catabolism persisted longer and remained elevated at 21 days post-infection. This finding is consistent with the prolonged duration of depression-like behaviors in aged mice. These are the first data using a chronic infection model to establish that recovery from inflammation-induced depression-like behavior and tryptophan catabolism are prolonged in aged animals. Copyright © 2013 Elsevier Inc. All rights reserved.

Alpha-Synuclein Expression Restricts RNA Viral Infections in the Brain.

PubMed

Beatman, Erica L; Massey, Aaron; Shives, Katherine D; Burrack, Kristina S; Chamanian, Mastooreh; Morrison, Thomas E; Beckham, J David

2015-12-30

We have discovered that native, neuronal expression of alpha-synuclein (Asyn) inhibits viral infection, injury, and disease in the central nervous system (CNS). Enveloped RNA viruses, such as West Nile virus (WNV), invade the CNS and cause encephalitis, yet little is known about the innate neuron-specific inhibitors of viral infections in the CNS. Following WNV infection of primary neurons, we found that Asyn protein expression is increased. The infectious titer of WNV and Venezuelan equine encephalitis virus (VEEV) TC83 in the brains of Asyn-knockout mice exhibited a mean increase of 10(4.5) infectious viral particles compared to the titers in wild-type and heterozygote littermates. Asyn-knockout mice also exhibited significantly increased virus-induced mortality compared to Asyn heterozygote or homozygote control mice. Virus-induced Asyn localized to perinuclear, neuronal regions expressing viral envelope protein and the endoplasmic reticulum (ER)-associated trafficking protein Rab1. In Asyn-knockout primary neuronal cultures, the levels of expression of ER signaling pathways, known to support WNV replication, were significantly elevated before and during viral infection compared to those in Asyn-expressing primary neuronal cultures. We propose a model in which virus-induced Asyn localizes to ER-derived membranes, modulates virus-induced ER stress signaling, and inhibits viral replication, growth, and injury in the CNS. These data provide a novel and important functional role for the expression of native alpha-synuclein, a protein that is closely associated with the development of Parkinson's disease. Neuroinvasive viruses such as West Nile virus are able to infect neurons and cause severe disease, such as encephalitis, or infection of brain tissue. Following viral infection in the central nervous system, only select neurons are infected, implying that neurons exhibit innate resistance to viral infections. We discovered that native neuronal expression of alpha-synuclein inhibited viral infection in the central nervous system. When the gene for alpha-synuclein was deleted, mice exhibited significantly decreased survival, markedly increased viral growth in the brain, and evidence of increased neuron injury. Virus-induced alpha-synuclein localized to intracellular neuron membranes, and in the absence of alpha-synuclein expression, specific endoplasmic reticulum stress signaling events were significantly increased. We describe a new neuron-specific inhibitor of viral infections in the central nervous system. Given the importance of alpha-synuclein as a cause of Parkinson's disease, these data also ascribe a novel functional role for the native expression of alpha-synuclein in the CNS. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

Economic burden of mucormycosis in the United States: can a vaccine be cost-effective?

PubMed

Ibrahim, Ashraf S; Edwards, John E; Bryant, Richard; Spellberg, Brad

2009-01-01

Mucormycosis is a life-threatening infection which causes unacceptably high morbidity and mortality despite treatment. Therefore, a vaccine to prevent mucormycosis is desirable. A major barrier to developing an anti-mucormycosis vaccine is the perception that such a vaccine would not be cost-effective to deploy because the disease is rare. We used data from a recent retrospective study to calculate the annual cost to the US healthcare system caused by mucormycosis infections. We created a model to estimate the cost-efficacy of a niche, anti-mucormycosis vaccine deployed in a targeted manner to high-risk patients. We found that each case of mucormycosis results in an average direct cost to the US healthcare system of $97,743, for an overall cost of mucormycosis of $50 million per year. In the base case scenario, targeted deployment of an anti-mucormycosis vaccine would result in a net cost per quality adjusted life year saved (QUALY) of $17,249. Variations in the price of the vaccine, its market penetration, or the cost of infection could dramatically decrease the net cost, and could even result in net savings per QUALY. In conclusion, mucormycosis causes considerable cost to the US health care system. Targeted deployment of a niche vaccine could decrease infection rates and mortality from mucormycosis in a cost-effective manner.

[Pathogenesis, diagnosis and therapy of Legionella infections].

PubMed

Lück, P C; Steinert, M

2006-05-01

Legionella species are ubiquitous in aquatic environments. About 50 years ago they entered the engineered (technical) environment, i.e. warm water systems with zones of stagnation. Since that time they represent a hygienic problem. After transmission to humans via aerosols legionellae might cause Legionella pneumonia (legionnaires' disease) or influenza-like respiratory infections (Pontiac fever). Epidemiological data suggest that Legionella strains might differ substantially in their virulence properties. Although the molecular basis is not understood L. pneumophila serogroup 1 especially MAb 3/1-positive strains cause the majority of infections. The main virulence feature is the ability to multiply intracellularly. After uptake into macrophages legionellae multiply in a specialized vacuole and finally lyse their host cells. Several bacterial factors like surface components, secretion systems and iron uptake systems are involved in this process. Since the clinical picture of Legionella pneumonia does not allow differentiation from pneumoniae caused by other pathogens, microbiological diagnostic methods are needed to establish the diagnosis. Cultivation of legionellae from clinical specimens, detection of antigens and DNA in patients' samples and detection of antibodies in serum samples are suitable methods. However, none of the diagnostic tests presently available offers the desired quality with respect to sensitivity and specificity. Therefore, the standard technique is to use several diagnostic tests in parallel. Advantages and disadvantages of the diagnostic procedures are discussed. Therapeutic options for Legionella infections are newer macrolides like azithromycin and chinolones (ciprofloxacin, levofloxacin and moxifloxacin).

A study of lymphoid organs and serum proinflammatory cytokines in pigs infected with African swine fever virus genotype II.

PubMed

Zakaryan, Hovakim; Cholakyans, Victorya; Simonyan, Lusine; Misakyan, Alla; Karalova, Elena; Chavushyan, Andranik; Karalyan, Zaven

2015-06-01

African swine fever virus (ASFV), the causative agent of one of the most important viral diseases of domestic pigs for which no vaccine is available, causes immune system disorders in infected animals. In this study, the serum levels of proinflammatory cytokines, as well as the histological and cellular constitution of lymphoid organs of pigs infected with ASFV genotype II were investigated. The results showed a high degree of lymphocyte depletion in the lymphoid organs, particularly in the spleen and lymph nodes, where ASFV infection led to a twofold decrease in the number of lymphocytes on the final day of infection. Additionally, ASFV-infected pigs had atypical forms of lymphocytes found in all lymphoid organs. In contrast to lymphocytes, the number of immature immune cells, particularly myelocytes, increased dramatically and reached a maximum on day 7 postinfection. The serum levels of TNF-α, IL-1β, IL-6, and IL-8 were evaluated. Proinflammatory cytokines showed increased levels after ASFV infection, with peak values at 7 days postinfection, and this highlights their role in the pathogenesis of ASFV. In conclusion, this study showed that ASFV genotype II, like other highly virulent strains, causes severe pathological changes in the immune system of pigs.

[Pathomorphology of experimental infection caused by powassan virus isolated in the Primorskiĭ Territory].

PubMed

Isachkova, L M; Frolova, M P; Leonova, G N; Karmysheva, V Ia; Somov, G P

1978-01-01

Pathomorphology of the infection caused by Powassan virus strains isolated in the Primorsky Kray was studied in white mice. The central nervous system of the animals sacrificed in the time course of the infectious process was studied by light and luminescent microscopy. Severe diffuse inflammatory-degenerative changes were found in the brain and spinal cord. Immunofluorescence revealed cytoplasmic localization of the virus antigen in neurons, glial and connective tissue cells.

Helminth Infections and Cardiovascular Diseases: Toxocara Species is Contributing to the Disease

PubMed Central

Zibaei, Mohammad

2017-01-01

Toxocariasis is the clinical term used to describe human infection with either the dog ascarid Toxocara canis or the feline ascarid Toxocara cati. As with other helminths zoonoses, the infective larvae of these Toxocara species cannot mature into adults in the human host. Instead, the worms wander through organs and tissues, mainly the liver, lungs, myocardium, kidney and central nervous system, in a vain attempt to find that, which they need to mature into adults. The migration of these immature nematode larvae causes local and systemic inflammation, resulting in the “larva migrans” syndrome. The clinical manifestations of toxocariasis are divided into visceral larva migrans, ocular larva migrans and neurotoxocariasis. Subclinical infection is often referred to as covert toxocariasis. One of the primary causes of death all around the world is cardiovascular disease that accounted for up to 30 percent of all-cause mortality. Cardiovascular disease and more precisely atherosclerotic cardiovascular disease, is predicted to remain the single leading cause of death (23.3 million deaths by 2030). A-quarter of people presenting the disease does not show any of the known cardiovascular risk factors. Therefore, there is considerable interest in looking for novel components affecting cardiovascular health, especially for those that could improve global cardiovascular risk prediction. This review endeavours to summarize the clinical aspects, new diagnostic and therapeutic perspectives of toxocaral disease with cardiovascular manifestations. PMID:27492228

Experimental system, and its evaluation for the control of surgically inducted infections

NASA Technical Reports Server (NTRS)

Tevebaugh, M. D.; Nelson, J. P.

1972-01-01

The effect is reported to design, fabricate, test and evaluate a prototype experimental system for the control of surgically induced infections. The purpose is to provide the cleanest possible environment within a hospital surgery room and eliminate contamination sources that could cause infections during surgery. The system design is described. The system provides for a portable laminar flow clean room, a full bubble helmet system with associated communications and ventilation subsystems for operating room personnel, and surgical gowns that minimize the migration of bacteria. The development test results consisting of portability, laminar flowrate, air flow pattern, electrostatic buildup, noise level, ventilation, human factors, electrical and material compatibility tests are summarized. The conclusions are that the experimental system is effective in reducing the airborne and wound contamination although the helmets and gowns may not be a significant part of this reduction. Definitive conclusions with regard to the infection rate cannot be made at this time.

Root canal treatment and general health: a review of the literature.

PubMed

Murray, C A; Saunders, W P

2000-01-01

The focal infection theory was prominent in the medical literature during the early 1900s and curtailed the progress of endodontics. This theory proposed that microorganisms, or their toxins, arising from a focus of circumscribed infection within a tissue could disseminate systemically, resulting in the initiation or exacerbation of systemic illness or the damage of a distant tissue site. For example, during the focal infection era rheumatoid arthritis (RA) was identified as having a close relationship with dental health. The theory was eventually discredited because there was only anecdotal evidence to support its claims and few scientifically controlled studies. There has been a renewed interest in the influence that foci of infection within the oral tissues may have on general health. Some current research suggests a possible relationship between dental health and cardiovascular disease and published case reports have cited dental sources as causes for several systemic illnesses. Improved laboratory procedures employing sophisticated molecular biological techniques and enhanced culturing techniques have allowed researchers to confirm that bacteria recovered from the peripheral blood during root canal treatment originated in the root canal. It has been suggested that the bacteraemia, or the associated bacterial endotoxins, subsequent to root canal treatment, may cause potential systemic complications. Further research is required, however, using current sampling and laboratory methods from scientifically controlled population groups to determine if a significant relationship between general health and periradicular infection exists.

Urinary tract infection with Pasteurella multocida in a patient with cat exposure and abnormal urinary tract physiology: Case report and literature review.

PubMed

Costanzo, Joel T; Wojciechowski, Amy L; Bajwa, Rajinder P S

2017-01-01

Pasteurella multocida is a gram-negative organism that commonly colonizes the mouth of cats and dogs, and is known to cause infection in humans associated with animal bites or scratches. Sites of infection other than skin and soft tissue are rare, but have been reported in patients with specific risk factors including anatomical abnormalities or immunosuppression. Herein, we report a case of a symptomatic urinary tract infection caused by P. multocida in a 59 year old female who presented to the hospital with complaints of systemic symptoms including malaise, rigors, and chills, as well as thick, malodorous urine. The patient self-catheterized multiple times daily due to urostomy with Kock pouch. Treatment with piperacillin/tazobactam followed by amoxicillin resulted in resolution of the infection.

Rhinosinusitis and disseminated cutaneous infection caused by Mycobacterium chelonae in an immunocompromised patient.

PubMed

Enomoto, Yasunori; Oba, Misao; Ishii, Norihisa; Nakanaga, Kazue; Yagi, Yuki; Hasegawa, Hirotsugu; Ozawa, Yuichi; Matsui, Takashi; Yokomura, Koshi; Suda, Takafumi

2015-09-01

Mycobacterium chelonae frequently involves the skin, and the disseminated form can be observed in immunocompromised patients. In contrast, rhinosinusitis caused by the bacterium is a rare manifestation, which occurs independently of immune status. We report here a rare case of M. chelonae infection presenting as both disseminated cutaneous infection and rhinosinusitis in an immunocompromised patient. He had received systemic corticosteroids for 11 months due to cryptogenic organizing pneumonia. Before admission, he sustained injuries to his left arm and hand; those injuries succumbed to an infection that would subsequently spread to his other limbs, face, and even nasal cavities. This valuable case suggests that disseminated cutaneous infection by M. chelonae could spread to other organs. Copyright © 2015 Japanese Society of Chemotherapy and The Japanese Association for Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

Pathogenesis of Infection by Clinical and Environmental Strains of Vibrio vulnificus in Iron-Dextran-Treated Mice

PubMed Central

Starks, Angela M.; Schoeb, Trenton R.; Tamplin, Mark L.; Parveen, Salina; Doyle, Thomas J.; Bomeisl, Philip E.; Escudero, Gloria M.; Gulig, Paul A.

2000-01-01

Vibrio vulnificus is an opportunistic pathogen that contaminates oysters harvested from the Gulf of Mexico. In humans with compromising conditions, especially excess levels of iron in plasma and tissues, consumption of contaminated seafood or exposure of wounds to contaminated water can lead to systemic infection and disfiguring skin infection with extremely high mortality. V. vulnificus-associated diseases are noted for the rapid replication of the bacteria in host tissues, with extensive tissue damage. In this study we examined the virulence attributes of three virulent clinical strains and three attenuated oyster or seawater isolates in mouse models of systemic disease. All six V. vulnificus strains caused identical skin lesions in subcutaneously (s.c.) inoculated iron dextran-treated mice in terms of numbers of recovered CFU and histopathology; however, the inocula required for identical frequency and magnitude of infection were at least 350-fold higher for the environmental strains. At lethal doses, all strains caused s.c. skin lesions with extensive edema, necrosis of proximate host cells, vasodilation, and as many as 108 CFU/g, especially in perivascular regions. These data suggest that the differences between these clinical and environmental strains may be related to growth in the host or susceptibility to host defenses. In non-iron dextran-treated mice, strains required 105-fold-higher inocula to cause an identical disease process as with iron dextran treatment. These results demonstrate that s.c. inoculation of iron dextran-treated mice is a useful model for studying systemic disease caused by V. vulnificus. PMID:10992486

The spectrum of aseptic central nervous system infections in southern Germany - demographic, clinical and laboratory findings.

PubMed

Kaminski, M; Grummel, V; Hoffmann, D; Berthele, A; Hemmer, B

2017-08-01

Aseptic infections of the central nervous system (CNS) are frequently observed in Germany. However, no study has systematically addressed the spectrum of aseptic CNS infections in Germany. Data on 191 adult patients diagnosed from January 2007 to December 2014 with aseptic meningitis or encephalitis/meningoencephalitis at our hospital were collected by chart review and analyzed for demographic, clinical and laboratory findings. Patients were stratified according to the causative virus and findings were compared between groups. In our cohort, meningitis was caused in 36% by enterovirus (EV), 15% by herpes simplex virus (HSV), 12% by varicella zoster virus (VZV) and 5% by tick borne encephalitis (TBE). Encephalitis/meningoencephalitis was caused in 13% by HSV, 13% by VZV, and three out of 11 tested patients were positive for TBE. The highest incidence of EV infections was between 25 and 35 years and of HSV infections between 30 and 60 years. VZV infections had a bimodal distribution peaking below 30 and above 70 years. VZV and EV infections were more frequently observed during summer, whereas HSV infections showed no seasonal preference. Inflammatory changes in cerebrospinal fluid (CSF) were highest in HSV and lowest in EV infections. Polymerase chain reaction tests for HSV, VZV and EV in CSF and TBE serology determined the causative virus in over 60% of tested patients. The age of affected patients, seasonal distribution, disease course and inflammatory changes in CSF differ between groups of patients affected by the most common viral infections. © 2017 EAN.

Herpes virus infection of the peripheral nervous system.

PubMed

Steiner, Israel

2013-01-01

Among the human herpes viruses, three are neurotropic and capable of producing severe neurological abnormalities: herpes simplex virus type 1 and 2 (HSV-1 and HSV-2) and varicella-zoster virus (VZV). Both the acute, primary infection and the reactivation from the site of latent infection, the dorsal sensory ganglia, are associated with severe human morbidity and mortality. The peripheral nervous system is one of the major loci affected by these viruses. The present review details the virology and molecular biology underlying the human infection. This is followed by detailed description of the symtomatology, clinical presentation, diagnosis, course, therapy, and prognosis of disorders of the peripheral nervous system caused by these viruses. Copyright © 2013 Elsevier B.V. All rights reserved.

Human parasitic protozoan infection to infertility: a systematic review.

PubMed

Shiadeh, Malihe Nourollahpour; Niyyati, Maryam; Fallahi, Shirzad; Rostami, Ali

2016-02-01

Protozoan parasitic diseases are endemic in many countries worldwide, especially in developing countries, where infertility is a major burden. It has been reported that such infections may cause infertility through impairment in male and female reproductive systems. We searched Medline, PubMed, and Scopus databases and Google scholar to identify the potentially relevant studies on protozoan parasitic infections and their implications in human and animal model infertility. Literature described that some of the protozoan parasites such as Trichomonas vaginalis may cause deformities of the genital tract, cervical neoplasia, and tubal and atypical pelvic inflammations in women and also non-gonoccocal urethritis, asthenozoospermia, and teratozoospermia in men. Toxopalasma gondii could cause endometritis, impaired folliculogenesis, ovarian and uterine atrophy, adrenal hypertrophy, vasculitis, and cessation of estrus cycling in female and also decrease in semen quality, concentration, and motility in male. Trypanosoma cruzi inhibits cell division in embryos and impairs normal implantation and development of placenta. Decrease in gestation rate, infection of hormone-producing glands, parasite invasion of the placenta, and overproduction of inflammatory cytokines in the oviducts and uterine horns are other possible mechanisms induced by Trypanosoma cruzi to infertility. Plasmodium spp. and Trypanosoma brucei spp. cause damage in pituitary gland, hormonal disorders, and decreased semen quality. Entamoeba histolytica infection leads to pelvic pain, salpingitis, tubo-ovarian abscess, and genital ulcers. Cutaneous and visceral leishmaniasis can induce genital lesion, testicular amyloidosis, inflammation of epididymis, prostatitis, and sperm abnormality in human and animals. In addition, some epidemiological studies have reported that rates of protozoan infections in infertile patients are higher than healthy controls. The current review indicates that protozoan parasitic infections may be an important cause of infertility. Given the widespread prevalence of parasitic protozoa diseases worldwide, we suggest further studies to better understanding of relationship between such infections and infertility.

Associations and Trends in Cause-Specific Rates of Death Among Persons Reported with HIV Infection, 23 U.S. Jurisdictions, Through 2011.

PubMed

Adih, William K; Selik, Richard M; Hall, H Irene; Babu, Aruna Surendera; Song, Ruiguang

2016-01-01

Published death rates for persons with HIV have not distinguished deaths due to HIV from deaths due to other causes. Cause-specific death rates would allow better assessment of care needs. Using data reported to the US national HIV surveillance system, we examined a) associations between selected decedent characteristics and causes of death during 2007-2011, b) trends in rates of death due to underlying causes among persons with AIDS during 1990-2011, and among all persons with diagnosed HIV infection (with or without AIDS) during 2000-2011. During 2007-2011, non-HIV-attributable causes of death with the highest rates per 1,000 person-years were heart disease (2.0), non-AIDS cancers other than lung cancer (1.4), and accidents (0.8). During 1990-2011, among persons with AIDS, the annual rate of death due to HIV-attributable causes decreased by 89% (from 122.0 to 13.2), and the rate due to non-HIV-attributable-causes decreased by 57% (from 20.0 to 8.6), while the percentage of deaths caused by non-HIV-attributable causes increased from 11% to 43%. During 2000-2011, among persons with HIV infection, the rate of death due to HIV-attributable causes decreased by 69% (from 26.4 to 8.3), and the rate due to non-HIV-attributable causes decreased by 28% (from 10.5 to 7.6), while the percentage of deaths caused by non-HIV-attributable causes increased from 25% to 48%. Among HIV-infected persons, as rates of death due to HIV-attributable causes decreased, rates due to non-HIV-attributable causes also decreased, but the percentages of deaths due to non-HIV-attributable causes, such as heart disease and non-AIDS cancers increased.

The role of TLRs in cervical cancer with HPV infection: a review

PubMed Central

Yang, Xiao; Cheng, Yanxiang; Li, Chunsheng

2017-01-01

The main cause of cervical cancer is persistent infection with high-risk human papilloma virus (HR-HPV), but not all human papilloma virus (HPV) infections lead to cervical cancer. The key factors that determine the outcome of HPV infection remain poorly understood, and how the host immune system protects against HPV infection is unclear. Toll-like receptors (TLRs) are a group of pattern recognition receptors present in the cytoplasm and cell membrane, and can specifically recognize pathogen-associated molecular patterns. As the key molecules of innate and acquired immunity, TLRs not only play important roles in the immune defense against infectious diseases, but also are involved in the occurrence and development of a variety of malignant tumors. In cervical cancer caused by HR-HPV infection, TLRs have been found to regulate the local immune microenvironment. The role of TLRs in HR-HPV infection and HPV-induced cervical cancer and its relationship with HPV vaccine are reviewed in this article. PMID:29263932

Pharmacological Blockade of the Chemokine Receptor CCR1 Protects Mice from Systemic Candidiasis of Hematogenous Origin

PubMed Central

Albert, Nathaniel D.; Swamydas, Muthulekha; Lee, Chyi-Chia R.; Loetscher, Pius

2016-01-01

ABSTRACT Systemic candidiasis is a leading cause of nosocomial bloodstream infection with a high mortality rate despite treatment. Immune-based strategies are needed to improve outcomes. We previously reported that genetic deficiency in the chemokine receptor CCR1 improves survival and ameliorates tissue damage in Candida-infected mice. Here, we found that treatment of immunocompetent Candida-infected mice with the CCR1-selective antagonist BL5923 improves survival, decreases the kidney fungal burden, and protects from renal tissue injury. PMID:27993850

Pathogenesis of Congenital Rubella Virus Infection in Human Fetuses: Viral Infection in the Ciliary Body Could Play an Important Role in Cataractogenesis.

PubMed

Nguyen, Thong Van; Pham, Van Hung; Abe, Kenji

2015-01-01

Development of congenital rubella syndrome associated with rubella virus infection during pregnancy is clinically important, but the pathogenicity of the virus remains unclear. Pathological examination was conducted on 3 aborted fetuses with congenital rubella infection. At autopsy, all 3 aborted fetuses showed congenital cataract confirmed by gross observation. Rubella virus infection occurred via systemic organs including circulating hematopoietic stem cells confirmed by immunohistochemical and molecular investigations, and major histopathogical changes were found in the liver. It is noteworthy that the virus infected the ciliary body of the eye, suggesting a possible cause of cataracts. Our study based on the pathological examination demonstrated that the rubella virus infection occurred via systemic organs of human fetuses. This fact was confirmed by immunohistochemistry and direct detection of viral RNA in multiple organs. To the best of our knowledge, this study is the first report demonstrating that the rubella virus infection occurred via systemic organs of the human body. Importantly, virus infection of the ciliary body could play an important role in cataractogenesis.

Toenail infection by Cladophialophora boppii.

PubMed

Brasch, J; Dressel, S; Müller-Wening, K; Hügel, R; von Bremen, D; de Hoog, G S

2011-02-01

Cladophialophora boppii is a black yeast-like fungus that up to now has been only rarely described as a cause of human infection and whose role as a pathogen was not established despite its repeated isolation and genetic identification in these reports. Here we report the first case of a verified toenail infection caused by this fungus in a woman without any systemic disease or evidence of immunodeficiency. Identical dark molds were isolated from the same toenail at three points of time. Species identification was performed by scrutinizing the isolates morphologic, physiologic and genetic characteristics which resulted in their identification as Cladophialophora boppii. Oral treatment with terbinafin plus topical ciclopiroxolamine was effective.

Genomic analysis of a Raoultella ornithinolytica strain causing prosthetic joint infection in an immunocompetent patient.

PubMed

Beye, Mamadou; Hasni, Issam; Seng, Piseth; Michelle, Caroline; La Scola, Bernard; Raoult, Didier; Fournier, Pierre-Edouard

2018-06-21

We sequenced the genome of Raoultella ornithinolytica strain Marseille-P1025 that caused a rare case of prosthetic joint infection in a 67-year-old immunocompetent male. The 6.7-Mb genome exhibited a genomic island (RoGI) that was unique among R. ornithinolytica strains. RoGI was likely acquired by lateral gene transfer from a member of the Pectobacterium genus and coded for a type IVa secretion system found in other pathogenic bacteria and that may have conferred strain Marseille-P1025 an increased virulence. Strain Marseille-P1025 was also able to infect, multiply within, and kill Acanthamoaeba castellanii amoebae.

Mycobacteria employ two different mechanisms to cross the blood-brain barrier.

PubMed

van Leeuwen, Lisanne M; Boot, Maikel; Kuijl, Coen; Picavet, Daisy I; van Stempvoort, Gunny; van der Pol, Susanne M A; de Vries, Helga E; van der Wel, Nicole N; van der Kuip, Martijn; van Furth, A Marceline; van der Sar, Astrid M; Bitter, Wilbert

2018-05-10

Central nervous system (CNS) infection by Mycobacterium tuberculosis is one of the most devastating complications of tuberculosis, in particular in early childhood. In order to induce CNS infection, M. tuberculosis needs to cross specialised barriers protecting the brain. How M. tuberculosis crosses the blood-brain barrier (BBB) and enters the CNS is not well understood. Here, we use transparent zebrafish larvae and the closely related pathogen Mycobacterium marinum to answer this question. We show that in the early stages of development, mycobacteria rapidly infect brain tissue, either as free mycobacteria or within circulating macrophages. After the formation of a functionally intact BBB, the infiltration of brain tissue by infected macrophages is delayed, but not blocked, suggesting that crossing the BBB via phagocytic cells is one of the mechanisms used by mycobacteria to invade the CNS. Interestingly, depletion of phagocytic cells did not prevent M. marinum from infecting the brain tissue, indicating that free mycobacteria can independently cause brain infection. Detailed analysis showed that mycobacteria are able to cause vasculitis by extracellular outgrowth in the smaller blood vessels and by infecting endothelial cells. Importantly, we could show that this second mechanism is an active process that depends on an intact ESX-1 secretion system, which extends the role of ESX-1 secretion beyond the macrophage infection cycle. © 2018 The Authors Cellular Microbiology Published by John Wiley & Sons Ltd.

Model systems for the study of Enterococcal colonization and infection

PubMed Central

Goh, H. M. Sharon; Yong, M. H. Adeline; Chong, Kelvin Kian Long

2017-01-01

ABSTRACT Enterococcus faecalis and Enterococcus faecium are common inhabitants of the human gastrointestinal tract, as well as frequent opportunistic pathogens. Enterococci cause a range of infections including, most frequently, infections of the urinary tract, catheterized urinary tract, bloodstream, wounds and surgical sites, and heart valves in endocarditis. Enterococcal infections are often biofilm-associated, polymicrobial in nature, and resistant to antibiotics of last resort. Understanding Enterococcal mechanisms of colonization and pathogenesis are important for identifying new ways to manage and intervene with these infections. We review vertebrate and invertebrate model systems applied to study the most common E. faecalis and E. faecium infections, with emphasis on recent findings examining Enterococcal-host interactions using these models. We discuss strengths and shortcomings of each model, propose future animal models not yet applied to study mono- and polymicrobial infections involving E. faecalis and E. faecium, and comment on the significance of anti-virulence strategies derived from a fundamental understanding of host-pathogen interactions in model systems. PMID:28102784

Inherited CARD9 deficiency in otherwise healthy children and adults with meningo-encephalitis and/or colitis caused by Candida

PubMed Central

Lanternier, Fanny; Mahdaviani, Seyed Alireza; Barbati, Elisa; Chaussade, Hélène; Koumar, Yatrika; Levy, Romain; Denis, Blandine; Brunel, Anne-Sophie; Martin, Sophie; Loop, Michèle; Peeters, Julie; de Selys, Ariel; Vanclaire, Jean; Vermylen, Christiane; Nassogne, Marie-Cécile; Chatzis, Olga; Liu, Luyan; Migaud, Mélanie; Pedergnana, Vincent; Desoubeaux, Guillaume; Jouvion, Gregory; Chretien, Fabrice; Darazam, Ilad Alavi; Schäffer, Alejandro A.; Netea, Mihai G.; De Bruycker, Jean-Jacques; Bernard, Louis; Reynes, Jacques; Amazrine, Noureddine; Abel, Laurent; Van der Linden, Dimitri; Harrison, Tom; Picard, Capucine; Lortholary, Olivier; Mansouri, Davood; Casanova, Jean-Laurent; Puel, Anne

2016-01-01

Invasive infections of the central nervous system or digestive tract caused by commensal fungi of the genus Candida are rare and life-threatening. The known risk factors include acquired and inherited immunodeficiencies, with patients often displaying a history of multiple infections. Cases of meningo-encephalitis and/or colitis caused by Candida remain unexplained. We studied five previously healthy children and adults with unexplained invasive disease of the central nervous system, or the digestive tract, or both, caused by Candida spp. The patients were aged 39, 7, 17 37, and 26 years at the time of infection and were unrelated but each born to consanguineous parents of Turkish (two patients), Iranian, Moroccan or Pakistani origin. Meningo-encephalitis was isolated in three patients, associated with colitis in a fourth patient, and the fifth patient suffered from isolated colitis. Inherited CARD9 deficiency was recently reported in otherwise healthy patients with other forms of severe disease caused by Candida, Trichophyton, Phialophora, and Exophiala, including meningo-encephalitis, but not colitis, caused by Candida and Exophiala. We therefore sequenced CARD9 in the five patients. All were found to be homozygous for rare and deleterious mutant CARD9 alleles: R70W and Q289* for the three patients with isolated C. albicans meningo-encephalitis, R35Q for the patient with meningo-encephalitis and colitis caused by C. glabrata, and Q295* for the patient with C. albicans colitis. Regardless of their levels of mutant CARD9 protein, the patients’ monocyte-derived dendritic cells responded poorly to CARD9-dependent fungal agonists (curdlan, heat-killed C. albicans, Saccharomyces cerevisiae and Exophiala dermatitidis). Invasive infections of the CNS or digestive tract caused by Candida in previously healthy children and even adults may be caused by inherited CARD9 deficiency. PMID:25702837

Suppression of IL-12p70 formation by IL-2 or following macrophage depletion causes T-cell autoreactivity leading to CNS demyelination in HSV-1-infected mice.

PubMed

Lee, Dhong Hyun; Zandian, Mandana; Kuo, Jane; Mott, Kevin R; Chen, Shuang; Arditi, Moshe; Ghiasi, Homayon

2017-05-01

We have established two mouse models of central nervous system (CNS) demyelination that differ from most other available models of multiple sclerosis (MS) in that they represent a mixture of viral and immune triggers. In the first model, ocular infection of different strains of mice with a recombinant HSV-1 that expresses murine IL-2 constitutively (HSV-IL-2) causes CNS demyelination. In the second model, depletion of macrophages causes CNS demyelination in mice that are ocularly infected with wild-type (WT) HSV-1. In the present study, we found that the demyelination in macrophage-intact mice infected with HSV-IL-2 was blocked by depletion of FoxP3-expressing cells, while concurrent depletion of macrophages restored demyelination. In contrast, demyelination was blocked in the macrophage-depleted mice infected with wild-type HSV-1 following depletion of FoxP3-expressing cells. In macrophage-depleted HSV-IL-2-infected mice, demyelination was associated with the activity of both CD4+ and CD8+ T cells, whereas in macrophage-depleted mice infected with WT HSV-1, demyelination was associated with CD4+ T cells. Macrophage depletion or infection with HSV-IL-2 caused an imbalance of T cells and TH1 responses as well as alterations in IL-12p35 and IL-12p40 but not other members of the IL-12 family or their receptors. Demyelination was blocked by adoptive transfer of macrophages that were infected with HSV-IL-12p70 or HSV-IL-12p40 but not by HSV-IL-12p35. These results indicate that suppression of IL-12p70 formation by IL-2 or following macrophage depletion causes T-cell autoreactivity leading to CNS demyelination in HSV-1-infected mice.

Suppression of IL-12p70 formation by IL-2 or following macrophage depletion causes T-cell autoreactivity leading to CNS demyelination in HSV-1-infected mice

PubMed Central

Lee, Dhong Hyun; Zandian, Mandana; Mott, Kevin R.; Chen, Shuang

2017-01-01

We have established two mouse models of central nervous system (CNS) demyelination that differ from most other available models of multiple sclerosis (MS) in that they represent a mixture of viral and immune triggers. In the first model, ocular infection of different strains of mice with a recombinant HSV-1 that expresses murine IL-2 constitutively (HSV-IL-2) causes CNS demyelination. In the second model, depletion of macrophages causes CNS demyelination in mice that are ocularly infected with wild-type (WT) HSV-1. In the present study, we found that the demyelination in macrophage-intact mice infected with HSV-IL-2 was blocked by depletion of FoxP3-expressing cells, while concurrent depletion of macrophages restored demyelination. In contrast, demyelination was blocked in the macrophage-depleted mice infected with wild-type HSV-1 following depletion of FoxP3-expressing cells. In macrophage-depleted HSV-IL-2-infected mice, demyelination was associated with the activity of both CD4+ and CD8+ T cells, whereas in macrophage-depleted mice infected with WT HSV-1, demyelination was associated with CD4+ T cells. Macrophage depletion or infection with HSV-IL-2 caused an imbalance of T cells and TH1 responses as well as alterations in IL-12p35 and IL-12p40 but not other members of the IL-12 family or their receptors. Demyelination was blocked by adoptive transfer of macrophages that were infected with HSV-IL-12p70 or HSV-IL-12p40 but not by HSV-IL-12p35. These results indicate that suppression of IL-12p70 formation by IL-2 or following macrophage depletion causes T-cell autoreactivity leading to CNS demyelination in HSV-1-infected mice. PMID:28542613

Prevalence, transmission and impact of bovine leukosis in Michigan dairies

USDA-ARS?s Scientific Manuscript database

Bovine leukosis, caused by infection with the retrovirus bovine leukemia virus (BLV), has been characterized as a contagious, but practically benign disease of the immune system. National Animal Health Monitoring Surveys in 1996 and 2007 indicate complacency has resulted in high prevalence of infect...

Acute Parasitic Infections as a Cause of Fever of Unknown Origin in Egypt

DTIC Science & Technology

1993-10-01

series and included 10 with acute and biliary system (Bassily et al., 1989). fascioliasis , 9 with schistosomiasis and I Diagnosing these patients...Farid et al., 1989). Acute Ilosp., Postal Code 11517, Cairo. Egpt. fascioliasis is treated with bithionol, 88 Table: Diagnostic categories of fcver of...diagnosis Infections 80 57 Tuberculosis (32), Salmonellosis (10), Fascioliasis (10), Schistosomiasis (9). Infective Endocarditis (5), Brucellosis (4

Use of Endophytic and Rhizosphere Actinobacteria from Grapevine Plants To Reduce Nursery Fungal Graft Infections That Lead to Young Grapevine Decline

PubMed Central

Álvarez-Pérez, José Manuel; González-García, Sandra; Cobos, Rebeca; Olego, Miguel Ángel; Ibañez, Ana; Díez-Galán, Alba; Garzón-Jimeno, Enrique

2017-01-01

ABSTRACT Endophytic and rhizosphere actinobacteria isolated from the root system of 1-year-old grafted Vitis vinifera plants were evaluated for their activities against fungi that cause grapevine trunk diseases. A total of 58 endophytic and 94 rhizosphere isolates were tested. Based on an in vitro bioassay, 15.5% of the endophytic isolates and 30.8% of the rhizosphere isolates exhibited antifungal activity against the fungal pathogen Diplodia seriata, whereas 13.8% of the endophytic isolates and 16.0% of the rhizosphere isolates showed antifungal activity against Dactylonectria macrodidyma (formerly Ilyonectria macrodidyma). The strains which showed the greatest in vitro efficacy against both pathogens were further analyzed for their ability to inhibit the growth of Phaeomoniella chlamydospora and Phaeoacremonium minimum (formerly Phaeoacremonium aleophilum). Based on their antifungal activity, three rhizosphere isolates and three endophytic isolates were applied on grafts in an open-root field nursery in a 3-year trial. The field trial led to the identification of one endophytic strain, Streptomyces sp. VV/E1, and two rhizosphere isolates, Streptomyces sp. VV/R1 and Streptomyces sp. VV/R4, which significantly reduced the infection rates produced by the fungal pathogens Dactylonectria sp., Ilyonectria sp., P. chlamydospora, and P. minimum, all of which cause young grapevine decline. The VV/R1 and VV/R4 isolates also significantly reduced the mortality level of grafted plants in the nursery. This study shows that certain actinobacteria could represent a promising new tool for controlling fungal trunk pathogens that infect grapevine plants through the root system in nurseries. IMPORTANCE Grapevine trunk diseases are a major threat to the wine and grape industry worldwide. They cause a significant reduction in yields as well as in grape quality, and they can even cause plant death. Trunk diseases are caused by fungal pathogens that enter through pruning wounds and/or the root system. Although different strategies have recently been developed to protect pruning wounds using antifungal compounds (natural or synthetic) or biocontrol agents, no tools are yet available for controlling soil pathogens that infect plants through their root system. This study shows that different actinobacterial isolates, when applied to grafts in a nursery, can significantly reduce the infection rate caused by fungal pathogens that enter through the root system. This is a new, promising, and green alternative for preventing the decline of young grapevines in nurseries and vineyards. PMID:28986378

Use of Endophytic and Rhizosphere Actinobacteria from Grapevine Plants To Reduce Nursery Fungal Graft Infections That Lead to Young Grapevine Decline.

PubMed

Álvarez-Pérez, José Manuel; González-García, Sandra; Cobos, Rebeca; Olego, Miguel Ángel; Ibañez, Ana; Díez-Galán, Alba; Garzón-Jimeno, Enrique; Coque, Juan José R

2017-12-15

Endophytic and rhizosphere actinobacteria isolated from the root system of 1-year-old grafted Vitis vinifera plants were evaluated for their activities against fungi that cause grapevine trunk diseases. A total of 58 endophytic and 94 rhizosphere isolates were tested. Based on an in vitro bioassay, 15.5% of the endophytic isolates and 30.8% of the rhizosphere isolates exhibited antifungal activity against the fungal pathogen Diplodia seriata , whereas 13.8% of the endophytic isolates and 16.0% of the rhizosphere isolates showed antifungal activity against Dactylonectria macrodidyma (formerly Ilyonectria macrodidyma ). The strains which showed the greatest in vitro efficacy against both pathogens were further analyzed for their ability to inhibit the growth of Phaeomoniella chlamydospora and Phaeoacremonium minimum (formerly Phaeoacremonium aleophilum ). Based on their antifungal activity, three rhizosphere isolates and three endophytic isolates were applied on grafts in an open-root field nursery in a 3-year trial. The field trial led to the identification of one endophytic strain, Streptomyces sp. VV/E1, and two rhizosphere isolates, Streptomyces sp. VV/R1 and Streptomyces sp. VV/R4, which significantly reduced the infection rates produced by the fungal pathogens Dactylonectria sp., Ilyonectria sp., P. chlamydospora , and P. minimum , all of which cause young grapevine decline. The VV/R1 and VV/R4 isolates also significantly reduced the mortality level of grafted plants in the nursery. This study shows that certain actinobacteria could represent a promising new tool for controlling fungal trunk pathogens that infect grapevine plants through the root system in nurseries. IMPORTANCE Grapevine trunk diseases are a major threat to the wine and grape industry worldwide. They cause a significant reduction in yields as well as in grape quality, and they can even cause plant death. Trunk diseases are caused by fungal pathogens that enter through pruning wounds and/or the root system. Although different strategies have recently been developed to protect pruning wounds using antifungal compounds (natural or synthetic) or biocontrol agents, no tools are yet available for controlling soil pathogens that infect plants through their root system. This study shows that different actinobacterial isolates, when applied to grafts in a nursery, can significantly reduce the infection rate caused by fungal pathogens that enter through the root system. This is a new, promising, and green alternative for preventing the decline of young grapevines in nurseries and vineyards. Copyright © 2017 American Society for Microbiology.

Systemic and mucosal immune reactivity upon Mycobacterium avium ssp. paratuberculosis infection in mice.

PubMed

Koc, Arzu; Bargen, Imke; Suwandi, Abdulhadi; Roderfeld, Martin; Tschuschner, Annette; Rath, Timo; Gerlach, Gerald F; Hornef, Mathias; Goethe, Ralph; Weiss, Siegfried; Roeb, Elke

2014-01-01

Mycobacterium avium ssp. paratuberculosis (MAP) is the cause of Johne's disease, an inflammatory bowel disorder of ruminants. Due to the similar pathology, MAP was also suggested to cause Crohn's disease (CD). Despite of intensive research, this question is still not settled, possibly due to the lack of versatile mouse models. The aim of this study was to identify basic immunologic mechanisms in response to MAP infection. Immune compromised C57BL/6 Rag2-/- mice were infected with MAP intraperitoneally. Such chronically infected mice were then reconstituted with CD4+ and CD8+ T cells 28 days after infection. A systemic inflammatory response, detected as enlargement of the spleen and granuloma formation in the liver, was observed in mice infected and reconstituted with CD4+ T cells. Whereby inflammation in infected and CD4+CD45RB(hi) T cell reconstituted animals was always higher than in the other groups. Reconstitution of infected animals with CD8+ T cells did not result in any inflammatory signs. Interestingly, various markers of inflammation were strongly up-regulated in the colon of infected mice reconstituted with CD4+CD45RB(lo/int) T cells. We propose, the usual non-colitogenic CD4+CD45RB(lo/int) T cells were converted into inflammatory T cells by the interaction with MAP. However, the power of such cells might be not sufficient for a fully established inflammatory response in the colon. Nevertheless, our model system appears to mirror aspects of an inflammatory bowel disease (IBD) like CD and Johne's diseases. Thus, it will provide an experimental platform on which further knowledge on IBD and the involvement of MAP in the induction of CD could be acquired.

Systemic and Mucosal Immune Reactivity upon Mycobacterium avium ssp. paratuberculosis Infection in Mice

PubMed Central

Suwandi, Abdulhadi; Roderfeld, Martin; Tschuschner, Annette; Rath, Timo; Gerlach, Gerald F.; Hornef, Mathias; Goethe, Ralph; Weiss, Siegfried; Roeb, Elke

2014-01-01

Mycobacterium avium ssp. paratuberculosis (MAP) is the cause of Johne's disease, an inflammatory bowel disorder of ruminants. Due to the similar pathology, MAP was also suggested to cause Crohn's disease (CD). Despite of intensive research, this question is still not settled, possibly due to the lack of versatile mouse models. The aim of this study was to identify basic immunologic mechanisms in response to MAP infection. Immune compromised C57BL/6 Rag2 −/− mice were infected with MAP intraperitoneally. Such chronically infected mice were then reconstituted with CD4+ and CD8+ T cells 28 days after infection. A systemic inflammatory response, detected as enlargement of the spleen and granuloma formation in the liver, was observed in mice infected and reconstituted with CD4+ T cells. Whereby inflammation in infected and CD4+CD45RBhi T cell reconstituted animals was always higher than in the other groups. Reconstitution of infected animals with CD8+ T cells did not result in any inflammatory signs. Interestingly, various markers of inflammation were strongly up-regulated in the colon of infected mice reconstituted with CD4+CD45RBlo/int T cells. We propose, the usual non-colitogenic CD4+CD45RBlo/int T cells were converted into inflammatory T cells by the interaction with MAP. However, the power of such cells might be not sufficient for a fully established inflammatory response in the colon. Nevertheless, our model system appears to mirror aspects of an inflammatory bowel disease (IBD) like CD and Johne's diseases. Thus, it will provide an experimental platform on which further knowledge on IBD and the involvement of MAP in the induction of CD could be acquired. PMID:24728142

Intraabdominal abscess related fungaemia caused by Rhodotorula glutinis in a non-neutropenic cancer patient.

PubMed

Diktas, H; Gulec, B; Baylan, O; Oncul, O; Turhan, V; Acar, A; Gorenek, L

2013-01-01

Rhodotorula glutinis is a rare fungal infection that is especially observed in immune-compromised patients. It is common in the skin, faeces, nails, sputum, gastrointestinal system and adenoid tissue. However, the incidence of Rhodotorula glutinis is increased in both local and systemic infections in recent years. Presented here is a case of Rhodotorula glutinis fungaemia that isolated from subhepatic abscess formation and blood in a patient who was operated with Roux-en-Y technique due to gastric adenocarcinoma. Fungal sepsis is an important cause of fever resistant to antibiotic therapy that is often taken into marginal account. It should instead be particularly considered in patients with a history of intraabdominal surgery and non-neutropenic cancer patients. The case described illustrates an episode of systemic infection by Rhodotorula glutinis, correlated with the presence of intraabdominal abscess and without central venous catheters. This is the first case of fungaemia by Rhodotorula glutinis with an intraabdominal abscess source reported from Turkey.

Systemic Escherichia coli infection does not influence clinical symptoms and neurodegeneration in experimental autoimmune encephalomyelitis.

PubMed

Kumar, Prateek; Friebe, Katharina; Schallhorn, Rieka; Moinfar, Zahra; Nau, Roland; Bähr, Mathias; Schütze, Sandra; Hein, Katharina

2015-06-19

Systemic infections can influence the course of multiple sclerosis (MS), especially by driving recurrent acute episodes. The question whether the infection enhances tissue damage is of great clinical importance and cannot easily be assessed in clinical trials. Here, we investigated the effects of a systemic infection with Escherichia coli, a Gram-negative bacterium frequently causing urinary tract infections, on the clinical course as well as on neurodegeneration in experimental autoimmune encephalomyelitis (EAE), an animal model of MS. Rats were immunized with myelin oligodendrocyte glycoprotein (MOG1-125) and challenged intraperitoneally with live E. coli K1 in the preclinical or in the clinical phase of the disease. To ensure the survival of animals, antibiotic treatment with ceftriaxone was initiated 36 h after the infection and continued for 3 consecutive days. Systemic infection with E. coli did not influence the onset of clinical EAE symptoms or disease severity. Analysis of the optic nerve and retinal ganglion cells revealed no significant changes in the extent of inflammatory infiltrates, demyelination and neurodegeneration after E. coli infection. We could not confirm the detrimental effect of lipopolysaccharide-induced systemic inflammation, a model frequently used to mimic the bacterial infection, previously observed in animal models of MS. Our results indicate that the effect of an acute E. coli infection on the course of MS is less pronounced than suspected and underline the need for adequate models to test the role of systemic infections in the pathogenesis of MS.

Complicated catheter-associated urinary tract infections due to Escherichia coli and Proteus mirabilis.

PubMed

Jacobsen, S M; Stickler, D J; Mobley, H L T; Shirtliff, M E

2008-01-01

Catheter-associated urinary tract infections (CAUTIs) represent the most common type of nosocomial infection and are a major health concern due to the complications and frequent recurrence. These infections are often caused by Escherichia coli and Proteus mirabilis. Gram-negative bacterial species that cause CAUTIs express a number of virulence factors associated with adhesion, motility, biofilm formation, immunoavoidance, and nutrient acquisition as well as factors that cause damage to the host. These infections can be reduced by limiting catheter usage and ensuring that health care professionals correctly use closed-system Foley catheters. A number of novel approaches such as condom and suprapubic catheters, intermittent catheterization, new surfaces, catheters with antimicrobial agents, and probiotics have thus far met with limited success. While the diagnosis of symptomatic versus asymptomatic CAUTIs may be a contentious issue, it is generally agreed that once a catheterized patient is believed to have a symptomatic urinary tract infection, the catheter is removed if possible due to the high rate of relapse. Research focusing on the pathogenesis of CAUTIs will lead to a better understanding of the disease process and will subsequently lead to the development of new diagnosis, prevention, and treatment options.

Complicated Catheter-Associated Urinary Tract Infections Due to Escherichia coli and Proteus mirabilis

PubMed Central

Jacobsen, S. M.; Stickler, D. J.; Mobley, H. L. T.; Shirtliff, M. E.

2008-01-01

Catheter-associated urinary tract infections (CAUTIs) represent the most common type of nosocomial infection and are a major health concern due to the complications and frequent recurrence. These infections are often caused by Escherichia coli and Proteus mirabilis. Gram-negative bacterial species that cause CAUTIs express a number of virulence factors associated with adhesion, motility, biofilm formation, immunoavoidance, and nutrient acquisition as well as factors that cause damage to the host. These infections can be reduced by limiting catheter usage and ensuring that health care professionals correctly use closed-system Foley catheters. A number of novel approaches such as condom and suprapubic catheters, intermittent catheterization, new surfaces, catheters with antimicrobial agents, and probiotics have thus far met with limited success. While the diagnosis of symptomatic versus asymptomatic CAUTIs may be a contentious issue, it is generally agreed that once a catheterized patient is believed to have a symptomatic urinary tract infection, the catheter is removed if possible due to the high rate of relapse. Research focusing on the pathogenesis of CAUTIs will lead to a better understanding of the disease process and will subsequently lead to the development of new diagnosis, prevention, and treatment options. PMID:18202436

The effect of malnutrition on norovirus infection.

PubMed

Hickman, Danielle; Jones, Melissa K; Zhu, Shu; Kirkpatrick, Ericka; Ostrov, David A; Wang, Xiaoyu; Ukhanova, Maria; Sun, Yijun; Mai, Volker; Salemi, Marco; Karst, Stephanie M

2014-03-04

Human noroviruses are the primary cause of severe childhood diarrhea in the United States, and they are of particular clinical importance in pediatric populations in the developing world. A major contributing factor to the general increased severity of infectious diseases in these regions is malnutrition-nutritional status shapes host immune responses and the composition of the host intestinal microbiota, both of which can influence the outcome of pathogenic infections. In terms of enteric norovirus infections, mucosal immunity and intestinal microbes are likely to contribute to the infection outcome in substantial ways. We probed these interactions using a murine model of malnutrition and murine norovirus infection. Our results reveal that malnutrition is associated with more severe norovirus infections as defined by weight loss, impaired control of norovirus infections, reduced antiviral antibody responses, loss of protective immunity, and enhanced viral evolution. Moreover, the microbiota is dramatically altered by malnutrition. Interestingly, murine norovirus infection also causes changes in the host microbial composition within the intestine but only in healthy mice. In fact, the infection-associated microbiota resembles the malnutrition-associated microbiota. Collectively, these findings represent an extensive characterization of a new malnutrition model of norovirus infection that will ultimately facilitate elucidation of the nutritionally regulated host parameters that predispose to more severe infections and impaired memory immune responses. In a broad sense, this model may provide insight into the reduced efficacy of oral vaccines in malnourished hosts and the potential for malnourished individuals to act as reservoirs of emergent virus strains. IMPORTANCE Malnourished children in developing countries are susceptible to more severe infections than their healthy counterparts, in particular enteric infections that cause diarrhea. In order to probe the effects of malnutrition on an enteric infection in a well-controlled system devoid of other environmental and genetic variability, we studied norovirus infection in a mouse model. We have revealed that malnourished mice develop more severe norovirus infections and they fail to mount effective memory immunity to a secondary challenge. This is of particular importance because malnourished children generally mount less effective immune responses to oral vaccines, and we can now use our new model system to probe the immunological basis of this impairment. We have also determined that noroviruses evolve more readily in the face of malnutrition. Finally, both norovirus infection and malnutrition independently alter the composition of the intestinal microbiota in substantial and overlapping ways.

A Web-Based, Hospital-Wide Health Care-Associated Bloodstream Infection Surveillance and Classification System: Development and Evaluation.

PubMed

Tseng, Yi-Ju; Wu, Jung-Hsuan; Lin, Hui-Chi; Chen, Ming-Yuan; Ping, Xiao-Ou; Sun, Chun-Chuan; Shang, Rung-Ji; Sheng, Wang-Huei; Chen, Yee-Chun; Lai, Feipei; Chang, Shan-Chwen

2015-09-21

Surveillance of health care-associated infections is an essential component of infection prevention programs, but conventional systems are labor intensive and performance dependent. To develop an automatic surveillance and classification system for health care-associated bloodstream infection (HABSI), and to evaluate its performance by comparing it with a conventional infection control personnel (ICP)-based surveillance system. We developed a Web-based system that was integrated into the medical information system of a 2200-bed teaching hospital in Taiwan. The system automatically detects and classifies HABSIs. In this study, the number of computer-detected HABSIs correlated closely with the number of HABSIs detected by ICP by department (n=20; r=.999 P<.001) and by time (n=14; r=.941; P<.001). Compared with reference standards, this system performed excellently with regard to sensitivity (98.16%), specificity (99.96%), positive predictive value (95.81%), and negative predictive value (99.98%). The system enabled decreasing the delay in confirmation of HABSI cases, on average, by 29 days. This system provides reliable and objective HABSI data for quality indicators, improving the delay caused by a conventional surveillance system.

Multi-Disciplinary Antimicrobial Strategies for Improving Orthopaedic Implants to Prevent Prosthetic Joint Infections in Hip and Knee

PubMed Central

Getzlaf, Matthew A.; Lewallen, Eric A.; Kremers, Hilal M.; Jones, Dakota L.; Bonin, Carolina A.; Dudakovic, Amel; Thaler, Roman; Cohen, Robert C.; Lewallen, David G.; van Wijnen, Andre J.

2016-01-01

Like any foreign object, orthopaedic implants are susceptible to infection when introduced into the human body. Without additional preventative measures, the absolute number of annual prosthetic joint infections will continue to rise, and may exceed the capacity of health care systems in the near future. Bacteria are difficult to eradicate from synovial joints due to their exceptionally diverse taxonomy, complex mechanistic attachment capabilities, and tendency to evolve antibiotic resistance. When a primary orthopaedic implant fails from prosthetic joint infection, surgeons are generally challenged by limited options for intervention. In this review, we highlight the etiology and taxonomic groupings of bacteria known to cause prosthetic joint infections, and examine their key mechanisms of attachment. We propose that antimicrobial strategies should focus on the most harmful bacteria taxa within the context of occurrence, taxonomic diversity, adhesion mechanisms, and implant design. Patient-specific identification of organisms that cause prosthetic joint infections will permit assessment of their biological vulnerabilities. The latter can be targeted using a range of antimicrobial techniques that exploit different colonization mechanisms including implant surface attachment, biofilm formation, and/or hematogenous recruitment. We anticipate that customized strategies for each patient, joint, and prosthetic component will be most effective at reducing prosthetic joint infections, including those caused by antibiotic-resistant and polymicrobial bacteria. PMID:26449208

Looking into Candida albicans infection, host response, and antifungal strategies.

PubMed

Wang, Yan

2015-01-01

Candida albicans, a commonly encountered fungal pathogen, causes diseases varying from superficial mucosal complaints to life-threatening systemic disorders. Among the virulence traits of C. albicans, yeast-to-hypha transition is most widely acknowledged. Host innate immunity to C. albicans critically requires pattern recognition receptors (PRRs), and defence against C. albicans infection is provided by an exquisite interplay between the innate and adaptive arms of the host immune system.

The Soriano Award Lecture. Emerging infections of the nervous system.

PubMed

Johnson, R T

1994-06-01

The epidemic of acquired immunodeficiency disease [AIDS] has focused interest on the origins of "new" infectious agents. Great plagues are well known from the distant past, but a number of novel diseases affecting the nervous system infections have emerged in recent years. The causes of such new disorders are diverse: whereas rapid mutations of microbes allow the evolution of truly novel agents, the appearance of new diseases is more often due to changes in human or vector populations or changes in societal mores that result in dissemination of preexistent microbes. Examples of recently emerging infections that involve the nervous system include the enterovirus 70 epidemics with poliomyelitis-like disease, the appearance of California virus encephalitis in the midwestern United States, the rapid spread of Lyme disease with its many neurological complications in the eastern United States, and the outbreak of bovine spongiform encephalopathy in the United Kingdom, in addition to the devastating epidemic of human immunodeficiency virus (HIV), which will cause nervous system disease in over half of those infected. As the world population increases and modern transportation brings us closer into a "global village" more new agents will emerge and more will be sustained. Knowledge of the molecular biology and ecology of the agents and awareness of how our actions can alter their behavior are our best defense.

Manipulation of host diet to reduce gastrointestinal colonization by the opportunistic pathogen Candida albicans

USDA-ARS?s Scientific Manuscript database

Candida albicans, the most common human fungal pathogen, can cause systemic infections with a mortality rate of ~40%. Infections arise from colonization of the gastrointestinal (GI) tract, where C. albicans is part of the normal microflora. Reducing colonization in at-risk patients using antifungal ...

Yogurt, immune function and infectious disease: can yogurt be used to protect the elderly against infections?

USDA-ARS?s Scientific Manuscript database

Systemic low-grade inflammation and immunosenescence occurs with aging, predisposing the elderly to myriad risk factors for infectious and chronic disease. Respiratory infections such as influenza and pneumonia are a leading cause of mortality in the elderly, and therefore of significant public hea...

Starvation reveals the cause of infection-induced castration and gigantism

PubMed Central

Cressler, Clayton E.; Nelson, William A.; Day, Troy; McCauley, Edward

2014-01-01

Parasites often induce life-history changes in their hosts. In many cases, these infection-induced life-history changes are driven by changes in the pattern of energy allocation and utilization within the host. Because these processes will affect both host and parasite fitness, it can be challenging to determine who benefits from them. Determining the causes and consequences of infection-induced life-history changes requires the ability to experimentally manipulate life history and a framework for connecting life history to host and parasite fitness. Here, we combine a novel starvation manipulation with energy budget models to provide new insights into castration and gigantism in the Daphnia magna–Pasteuria ramosa host–parasite system. Our results show that starvation primarily affects investment in reproduction, and increasing starvation stress reduces gigantism and parasite fitness without affecting castration. These results are consistent with an energetic structure where the parasite uses growth energy as a resource. This finding gives us new understanding of the role of castration and gigantism in this system, and how life-history variation will affect infection outcome and epidemiological dynamics. The approach of combining targeted life-history manipulations with energy budget models can be adapted to understand life-history changes in other disease systems. PMID:25143034

Starvation reveals the cause of infection-induced castration and gigantism.

PubMed

Cressler, Clayton E; Nelson, William A; Day, Troy; McCauley, Edward

2014-10-07

Parasites often induce life-history changes in their hosts. In many cases, these infection-induced life-history changes are driven by changes in the pattern of energy allocation and utilization within the host. Because these processes will affect both host and parasite fitness, it can be challenging to determine who benefits from them. Determining the causes and consequences of infection-induced life-history changes requires the ability to experimentally manipulate life history and a framework for connecting life history to host and parasite fitness. Here, we combine a novel starvation manipulation with energy budget models to provide new insights into castration and gigantism in the Daphnia magna-Pasteuria ramosa host-parasite system. Our results show that starvation primarily affects investment in reproduction, and increasing starvation stress reduces gigantism and parasite fitness without affecting castration. These results are consistent with an energetic structure where the parasite uses growth energy as a resource. This finding gives us new understanding of the role of castration and gigantism in this system, and how life-history variation will affect infection outcome and epidemiological dynamics. The approach of combining targeted life-history manipulations with energy budget models can be adapted to understand life-history changes in other disease systems.

10 x '20 Progress--development of new drugs active against gram-negative bacilli: an update from the Infectious Diseases Society of America.

PubMed

Boucher, Helen W; Talbot, George H; Benjamin, Daniel K; Bradley, John; Guidos, Robert J; Jones, Ronald N; Murray, Barbara E; Bonomo, Robert A; Gilbert, David

2013-06-01

Infections caused by antibiotic-resistant bacteria, especially the "ESKAPE" pathogens, continue to increase in frequency and cause significant morbidity and mortality. New antimicrobial agents are greatly needed to treat infections caused by gram-negative bacilli (GNB) resistant to currently available agents. The Infectious Diseases Society of America (IDSA) continues to propose legislative, regulatory, and funding solutions to this continuing crisis. The current report updates the status of development and approval of systemic antibiotics in the United States as of early 2013. Only 2 new antibiotics have been approved since IDSA's 2009 pipeline status report, and the number of new antibiotics annually approved for marketing in the United States continues to decline. We identified 7 drugs in clinical development for treatment of infections caused by resistant GNB. None of these agents was included in our 2009 list of antibacterial compounds in phase 2 or later development, but unfortunately none addresses the entire spectrum of clinically relevant GNB resistance. Our survey demonstrates some progress in development of new antibacterial drugs that target infections caused by resistant GNB, but progress remains alarmingly elusive. IDSA stresses our conviction that the antibiotic pipeline problem can be solved by the collaboration of global leaders to develop creative incentives that will stimulate new antibacterial research and development. Our aim is the creation of a sustainable global antibacterial drug research and development enterprise with the power in the short term to develop 10 new, safe, and efficacious systemically administered antibiotics by 2020 as called for in IDSA's "10 × '20 Initiative."

Recurrent Soft Tissue Abscesses Caused by Legionella cincinnatiensis

PubMed Central

Gubler, Jacques G. H.; Schorr, Mirjam; Gaia, V.; Zbinden, R.; Altwegg, M.

2001-01-01

Recurrent soft tissue abscesses of the jaw, wrist, and arm developed in a 73-year-old housewife with nephrotic syndrome and immunoglobulin A(κ) gammopathy of unknown etiology. Conventional cultures remained negative, despite visible gram-negative rods on microscopy. Broad-spectrum PCR revealed Legionella cincinnatiensis, which was confirmed by isolation of the organism on special Legionella medium. Infections due to Legionella species outside the lungs are rare. L. cincinnatiensis has been implicated in only four cases of clinical infection; these involved the lungs in three patients and the central nervous system in one patient. We conclude that broad-spectrum PCR can be a valuable tool for the evaluation of culture-negative infections with a high probability of bacterial origin and that Legionella might be an underdiagnosed cause of pyogenic soft tissue infection. PMID:11724886

Whole-animal imaging of bacterial infection using endoscopic excitation of β-lactamase (BlaC)-specific fluorogenic probe

NASA Astrophysics Data System (ADS)

Nooshabadi, Fatemeh; Yang, Hee-Jeong; Cheng, Yunfeng; Xie, Hexin; Rao, Jianghong; Cirillo, Jeffrey D.; Maitland, Kristen C.

2016-03-01

Tuberculosis (TB), caused by Mycobacterium tuberculosis (Mtb), remains one of the most frequent causes of death worldwide. The slow growth rate of Mtb limits progress toward understanding tuberculosis including diagnosis of infections and evaluating therapeutic efficacy. Development of near-infrared (NIR) β-lactamase (BlaC)-specific fluorogenic substrate has made a significant breakthrough in the whole-animal imaging to detect Mtb infection. The reporter enzyme fluorescence (REF) system using a BlaC-specific fluorogenic substrate has improved the detection sensitivity in whole-animal optical imaging down to ~104 colony forming units (CFU) of bacteria, about 100-fold improvement over recombinant strains. However, improvement of detection sensitivity is strongly needed for clinical diagnosis of early stage infection at greater tissue depth. In order to improve detection sensitivity, we have integrated a fiber-based microendoscpe into a whole-animal imaging system to transmit the excitation light from the fiber bundle to the fluorescent target directly and measure fluorescent level using BlaC-specific REF substrate in the mouse lung. REF substrate, CNIR800, was delivered via aerosol route to the pulmonary infected mice with M. bovis BCG strain at 24 hours post-infection and groups of mice were imaged at 1-4 hours post-administration of the substrate using the integrated imaging system. In this study we evaluated the kinetics of CNIR800 substrate using REF technology using the integrated imaging system. Integration of these technologies has great promise for improved detection sensitivity allowing pre-clinical imaging for evaluation of new therapeutic agents.

Impact of the introduction of an automated microbiologic system on the clinical outcomes of bloodstream infections caused by Enterobacteriaceae strains.

PubMed

Callefi, Luciana Azevedo; Medeiros, Eduardo Alexandrino Servolo de; Furtado, Guilherme Henrique Campos

2013-01-01

Enterobacteriaceae strains are a leading cause of bloodstream infections (BSI). The aim of this study is to assess differences in clinical outcomes of patients with BSI caused by Enterobacteriaceae strains before and after introduction of an automated microbiologic system by the microbiology laboratory. We conducted a retrospective cohort study aimed to evaluate the impact of the introduction of an automated microbiologic system (Phoenix(tm) automated microbiology system, Becton, Dickinson and Company (BD) - Diagnostic Systems, Sparks, MD, USA) on the outcomes of BSIs caused by Enterobacteriaceae strains. The study was undertaken at Hospital São Paulo, a 750-bed teaching hospital in São Paulo, Brazil. Patients with BSI caused by Enterobacteriaceae strains before the introduction of the automated system were compared with patients with BSI caused by the same pathogens after the introduction of the automated system with regard to treatment adequacy, clinical cure/improvement and 14- and 28-day mortality rates. We evaluated 90 and 106 patients in the non-automated and automated testing periods, respectively. The most prevalent species in both periods were Klebsiella spp. and Proteus spp. Clinical cure/improvement occurred in 70% and 67.9% in non-automated and automated period, respectively (p = 0.75). 14-day mortality rates were 22.2% and 30% (p = 0.94) and 28-day mortality rates were 24.5% and 40.5% (p = 0.12). There were no significant differences between the two testing periods with regard to treatment adequacy, clinical cure/improvement and 14- and 28-day mortality rates. Introduction of the BD Phoenix(tm) automated microbiology system did not impact the clinical outcomes of BSIs caused by Enterobacteriaceae strains in our setting.

Liver abscess caused by periodontal bacterial infection with Fusobacterium necrophorum.

PubMed

Yoneda, Masato; Kato, Shingo; Mawatari, Hironori; Kirikoshi, Hiroyuki; Imajo, Kento; Fujita, Koji; Endo, Hiroki; Takahashi, Hirokazu; Inamori, Masahiko; Kobayashi, Noritoshi; Kubota, Kensuke; Saito, Satoru; Tohnai, Iwai; Watanuki, Kei; Wada, Koichiro; Maeda, Shin; Nakajima, Atsushi

2011-02-01

Liver abscess is recognized as a life-threatening disease. However, even in recent years, approximately 50% of liver abscess cases are considered to be cryptogenic. Here, we report a case of liver abscess associated with periodontal bacterial infection by Fusobacterium necrophorum, which is commonly found in the oropharyngeal flora. A 36-year-old man presented with fever and contrast-enhanced abdominal computed tomography revealed multiple liver abscesses. F.necrophorum was isolated from oral smears, liver aspirates and blood samples. Liver abscesses caused by periodontal bacterial infection are rare, however, the incidence is expected to increase in the future, as periodontitis is extremely common and is on the rise as one of the most common chronic infections in the world. A systemic survey including periodontitis may be required for the exact diagnosis of the source of infection. © 2011 The Japan Society of Hepatology.

Impact of methicillin-resistant Staphylococcus Aureus (MRSA) infection on patient outcome after pancreatoduodenectomy (PD)--a cause for concern?

PubMed

Sanjay, Pandanaboyana; Fawzi, Ali; Kulli, Christoph; Polignano, Francesco M; Tait, Iain S

2010-11-01

This study evaluated the impact of methicillin-resistant Staphylococcus aureus (MRSA) hospital-acquired infection on postoperative complications and patient outcome after pancreatoduodenectomy (PD). Seventy-nine patients who underwent PD were monitored for hospital-acquired MRSA. The patients were grouped as (1) no MRSA infection, (2) skin colonization with MRSA, and (3) systemic MRSA infection. Forty (51%) of the 79 patients were MRSA positive during hospital admission. Fourteen of the 40 patients swabbed for MRSA were found positive (skin colonization), and 26 patients (33%) developed systemic MRSA infection after PD. The sites of MRSA infection included (1) abdominal drain fluid (16/26; 42%), (2) sputum (4/26; 15%), (3) blood cultures (2/26; 8%), and (4) combination of sites (9/26; 35%). The patients with systemic MRSA infection had a longer postoperative stay (31 vs 22 days; P = 0.005) and increased incidence of chest infections compared with MRSA-negative patients (14 vs 4; P = 0.02). Four of the 16 patients with MRSA-positive drain fluid had a postpancreatectomy hemorrhage compared with 3 of the 63 patients with no MRSA infection in drain fluid (P = 0.02). Of the 79 patients admitted for PD, 51% became colonized with MRSA infection. Systemic hospital-acquired MRSA infection in 33% was associated with prolonged postoperative stay, increased wound and chest infections, and increased risk of postoperative hemorrhage.

Autoimmune encephalitis and its relation to infection.

PubMed

Venkatesan, Arun; Benavides, David R

2015-03-01

Encephalitis, an inflammatory condition of the brain that results in substantial morbidity and mortality, has numerous causes. Over the past decade, it has become increasingly recognized that autoimmune conditions contribute significantly to the spectrum of encephalitis causes. Clinical suspicion and early diagnosis of autoimmune etiologies are of particular importance due to the need for early institution of immune suppressive therapies to improve outcome. Emerging clinical observations suggest that the most commonly recognized cause of antibody-mediated autoimmune encephalitis, anti-N-methyl-D-aspartate (NMDA) receptor encephalitis, may in some cases be triggered by herpes virus infection. Other conditions such as Rasmussen's encephalitis (RE) and febrile infection-related epilepsy syndrome (FIRES) have also been posited to be autoimmune conditions triggered by infectious agents. This review focuses on emerging concepts in central nervous system autoimmunity and addresses clinical and mechanistic findings linking autoimmune encephalitis and infections. Particular consideration will be given to anti-NMDA receptor encephalitis and its relation to herpes simplex encephalitis.

Incidence of varicella zoster virus infections of the central nervous system in the elderly: a large tertiary hospital-based series (2007-2014).

PubMed

Arruti, M; Piñeiro, L D; Salicio, Y; Cilla, G; Goenaga, M A; López de Munain, A

2017-06-01

The aim of the study was to describe the clinical and epidemiological characteristics of the central nervous system (CNS) infection by varicella zoster virus (VZV) in patients older than 65 years in a tertiary community hospital. We retrospectively analysed the results of cerebrospinal fluid (CSF) testing in patients older than 65 years between 2007 and 2014 with clinically suspected VZV infection with CNS involvement. Patients whose CSF samples were positive for VZV DNA were included, as were those with negative results who simultaneously presented herpes zoster and CSF or magnetic resonance imaging findings suggestive of CNS infection, and in whom other possible aetiologies had been ruled out. The study included 280 patients. The disease was considered to be caused by a VZV infection in 32 patients (11.4%), of which 23 cases were virologically confirmed (detection of VZV DNA in CSF). The most frequent diagnosis of the patients with VZV CNS infection was encephalitis (83.3%), followed by meningitis (13.3%) and cerebellitis (3.3%). The mean annual incidence of VZV CNS infection was 3.0 cases per 100,000 inhabitants. VZV was the most common cause of encephalitis and viral meningitis, ahead of herpes simplex virus (n = 9). At the time of discharge, 12 (40%) patients showed neurological sequelae. Five patients (20%) died during hospitalization, all with encephalitis. Patients with a fatal outcome had significantly higher median age and longer delay before initiating acyclovir. In conclusion, VZV was the first cause of encephalitis in our elderly population. Despite acyclovir treatment, there was a high rate of case fatality and sequelae at discharge.

Differential Disease Susceptibilities in Experimentally Reptarenavirus-Infected Boa Constrictors and Ball Pythons

PubMed Central

Sanchez-Migallon Guzman, David; Garcia, Valentina E.; Layton, Marylee L.; Hoon-Hanks, Laura L.; Boback, Scott M.; Keel, M. Kevin; Drazenovich, Tracy

2017-01-01

ABSTRACT Inclusion body disease (IBD) is an infectious disease originally described in captive snakes. It has traditionally been diagnosed by the presence of large eosinophilic cytoplasmic inclusions and is associated with neurological, gastrointestinal, and lymphoproliferative disorders. Previously, we identified and established a culture system for a novel lineage of arenaviruses isolated from boa constrictors diagnosed with IBD. Although ample circumstantial evidence suggested that these viruses, now known as reptarenaviruses, cause IBD, there has been no formal demonstration of disease causality since their discovery. We therefore conducted a long-term challenge experiment to test the hypothesis that reptarenaviruses cause IBD. We infected boa constrictors and ball pythons by cardiac injection of purified virus. We monitored the progression of viral growth in tissues, blood, and environmental samples. Infection produced dramatically different disease outcomes in snakes of the two species. Ball pythons infected with Golden Gate virus (GoGV) and with another reptarenavirus displayed severe neurological signs within 2 months, and viral replication was detected only in central nervous system tissues. In contrast, GoGV-infected boa constrictors remained free of clinical signs for 2 years, despite high viral loads and the accumulation of large intracellular inclusions in multiple tissues, including the brain. Inflammation was associated with infection in ball pythons but not in boa constrictors. Thus, reptarenavirus infection produces inclusions and inclusion body disease, although inclusions per se are neither necessarily associated with nor required for disease. Although the natural distribution of reptarenaviruses has yet to be described, the different outcomes of infection may reflect differences in geographical origin. IMPORTANCE New DNA sequencing technologies have made it easier than ever to identify the sequences of microorganisms in diseased tissues, i.e., to identify organisms that appear to cause disease, but to be certain that a candidate pathogen actually causes disease, it is necessary to provide additional evidence of causality. We have done this to demonstrate that reptarenaviruses cause inclusion body disease (IBD), a serious transmissible disease of snakes. We infected boa constrictors and ball pythons with purified reptarenavirus. Ball pythons fell ill within 2 months of infection and displayed signs of neurological disease typical of IBD. In contrast, boa constrictors remained healthy over 2 years, despite high levels of virus throughout their bodies. This difference matches previous reports that pythons are more susceptible to IBD than boas and could reflect the possibility that boas are natural hosts of these viruses in the wild. PMID:28515291

Percutaneous Management of Systemic Fungal Infection Presenting As Bilateral Renal Fungal Ball

PubMed Central

Shukla, Abhishek; Shrivastava, Nitin; Singh, Chirom Amit

2016-01-01

Abstract Background: Zygomycoses are uncommon, frequently fatal diseases caused by fungi of the class Zygomycetes. The majority of human cases are caused by Mucorales (genus—rhizopus, mucor, and absidia) fungi. Renal involvement is uncommon and urine microscopy, pottasium hydroxide mount, and fungal cultures are frequently negative. Case Presentation: A twenty-one-year-old young unmarried lady presented to our emergency department with bilateral flank pain, fever, nausea, and decreased urine output of one-month duration. She was found to have azotemia with sepsis with bilateral hydronephrosis with a left renal pelvic obstructing stone. Even after nephrostomy drainage and broad spectrum antibiotics, her condition worsened. She developed disseminated fungal infection, and timely systemic antifungal followed by bilateral nephroscopic clearance saved the patient. Conclusion: Although renal fungal infections are uncommon, a high index of suspicion and early antifungal and surgical intervention can give favorable outcomes. PMID:27704055

Percutaneous Management of Systemic Fungal Infection Presenting As Bilateral Renal Fungal Ball.

PubMed

Shukla, Abhishek; Shrivastava, Nitin; Singh, Chirom Amit; Nayak, Brusabhanu

2016-01-01

Background: Zygomycoses are uncommon, frequently fatal diseases caused by fungi of the class Zygomycetes. The majority of human cases are caused by Mucorales (genus-rhizopus, mucor, and absidia) fungi. Renal involvement is uncommon and urine microscopy, pottasium hydroxide mount, and fungal cultures are frequently negative. Case Presentation: A twenty-one-year-old young unmarried lady presented to our emergency department with bilateral flank pain, fever, nausea, and decreased urine output of one-month duration. She was found to have azotemia with sepsis with bilateral hydronephrosis with a left renal pelvic obstructing stone. Even after nephrostomy drainage and broad spectrum antibiotics, her condition worsened. She developed disseminated fungal infection, and timely systemic antifungal followed by bilateral nephroscopic clearance saved the patient. Conclusion: Although renal fungal infections are uncommon, a high index of suspicion and early antifungal and surgical intervention can give favorable outcomes.

Orbital Apex Syndrome Caused by Invasive Aspergillosis as an Adverse Effect of Systemic Chemotherapy for Metastatic Colorectal Cancer: a Case Report.

PubMed

Miyamoto, Yuji; Sakamoto, Yasuo; Ohuchi, Mayuko; Tokunaga, Ryuma; Shigaki, Hironobu; Kurashige, Junji; Iwatsuki, Masaaki; Baba, Yoshifumi; Yoshida, Naoya; Watanabe, Masayuki; Baba, Hideo

2016-02-01

Continuous therapy with cytotoxic drugs suppresses humoral immune function and may result in local infection. We present a case of orbital apex syndrome caused by Aspergillus infection during chemotherapy for metastatic colorectal cancer. A 74-year-old man with colorectal liver metastases under long-term continuous systemic chemotherapy presented with painful, progressive orbital apex syndrome. Magnetic resonance imaging disclosed a small enhancing lesion around the right ethmoid sinus. We initially diagnosed colorectal cancer metastasis and he underwent biopsy via the endoscopic endonasal transethmoid approach. However, pathological examination of the cultured specimen revealed Aspergillus fumigatus. The patient was treated with voriconazole and the orbital apex syndrome resolved after 1 month. Orbital aspergillosis is a life-threatening disease and should be listed as a differential diagnosis of uncommon local infections during continuous chemotherapy. Copyright© 2016 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

The accessory gene regulator (agr) controls Staphylococcus aureus virulence in a murine intracranial abscesses model.

PubMed

Gong, Jian; Li, Dongzhi; Yan, Jun; Liu, Yu; Li, Di; Dong, Jie; Gao, Yaping; Sun, Tao; Yang, Guang

2014-01-01

Intracranial abscesses are associated with high mortality. Staphylococcus aureus is one of the main pathogens that cause intracranial infection. Until now, there is no report to identify the key effectors of S. aureus during the intracranial infection. The murine intracranial abscesses model induced by S. aureus was constructed. The vital sign and survival rate of mice were observed to evaluate the infection. Histological examination was used to diagnose the pathological alterations of mouse tissues. The sensitivity of S. aureus to whole blood was evaluated by whole-blood killing assay. In murine intracranial abscesses model, it was shown that the mortality caused by the accessory gene regulator (agr) locus deficient strain was significant decreased compared with its parent strain. Moreover, we found that RNAIII, the effector of agr system, was essential for the intracranial infection caused by S. aureus. In the further investigation, it was shown that restoration the expression of α-toxin in agr deficient strain could partially recover the mortality in the murine intracranial abscesses model. Our data suggested that the agr system of S. aureus is an important virulence determinant in the induction and mortality of intracranial abscesses in mice. Copyright © 2014 Elsevier Editora Ltda. All rights reserved.

Maintaining the Body's Immune System: Incidence of Latent Virus Shedding During Space Flight

NASA Technical Reports Server (NTRS)

Pierson, Duane; Bloomberg, Jacob; Lee, Angie (Technical Monitor)

2002-01-01

Your body protects you from illness with its own security system - the immune system. This system keeps illness at bay not only by mounting a defense against foreign organisms, but also by controlling the population of bacteria and viruses that normally live in your body. But there's no need to panic: certain microbes can actually exist in your body without causing illness. Some bacteria are even beneficial - like the E. coli in the large intestine that are an important source of vitamin K. While viruses are not exactly considered beneficial, they can also inhabit the human body without causing immediate harm or infection. A good example is the herpes simplex virus type 1 (HSV1), more commonly known as cold sores or fever blisters. This virus infects 70 to 80 percent of all adults but remains latent much of the time. While latent, the virus within cells remains dormant. Activation of the dormant virus causes it to make copies of itself (known as replication) constantly detectable in body fluids such as urine or saliva in a process called shedding. When a person becomes sick or stressed, however, this weakened condition allows the virus to reactivate and multiply. These elevated levels may be enough to produce symptoms, but shedding can also occur without symptoms. This ability to shed without showing signs of infection, or asymptomatic shedding, is of great interest, as it increases the chances of infecting others. The stresses associated with space flight - adapting to microgravity, isolation from family and friends, living and working in a confined space, sleep deprivation, and busy schedules, to name but a few - may weaken astronauts' immune systems, leaving them at greater risk of viral reactivation. Members of the STS-107 crew will participate in this experiment, Incidence of Latent Viral Shedding in Space Flight, to help scientists understand how reactivation works in space, and at what level replication reaches before symptoms begin to show. This study also promises more insight into the behavior of the larger virus family, herpesvirus, which will help us understand how to prevent infection in populations on Earth and reactivation in those already infected.

Exit-site infections by non-diphtheria corynebacteria in CAPD.

PubMed

Schiffl, Helmut; Mücke, Claudia; Lang, Susanne M

2004-01-01

Non-diphtheria corynebacteria species cause disease in risk populations such as immunocompromised patients and patients with indwelling medical devices. Despite reports of exit-site infection and peritonitis caused by non-diphtheria corynebacteria, these organisms are frequently dismissed as contaminants. During a 10-year observation period, we prospectively identified 8 cases of exit-site/tunnel infections caused by 2 different species of corynebacteria (Corynebacterium striatum in 5 and C. jeikeium in 3 cases). Four patients experienced a second episode of exit-site infection 3 months (2 cases), 25 months, and 40 months, respectively, after termination of an oral cephalosporin therapy of 4 to 6 weeks' duration. Non-diphtheria corynebacteria accounted for 9% of all exit-site infections during the study period. All catheter-related infections healed; no catheter had to be removed. The diagnosis of catheter-related non-diphtheria corynebacteria infection may be suspected when Gram stain shows gram-positive rods and with colony morphology and commercial biochemical identification systems. Susceptibility of non-diphtheria corynebacteria to antibiotics may vary, especially in C. jeikeium. Virtually all Corynebacterium species are sensitive to vancomycin. Empirical antibiotic therapy with vancomycin should be initiated while antibiotic susceptibility testing is being carried out. Oral cephalosporin may be an alternative treatment regimen for exit-site infections if sensitive. This study highlights the importance of non-diphtheria corynebacteria as emerging nosocomial pathogens in the population of end-stage renal disease patients on on continuous ambulatory peritoneal dialysis.

Neurotropic Enterovirus Infections in the Central Nervous System.

PubMed

Huang, Hsing-I; Shih, Shin-Ru

2015-11-24

Enteroviruses are a group of positive-sense single stranded viruses that belong to the Picornaviridae family. Most enteroviruses infect humans from the gastrointestinal tract and cause mild symptoms. However, several enteroviruses can invade the central nervous system (CNS) and result in various neurological symptoms that are correlated to mortality associated with enteroviral infections. In recent years, large outbreaks of enteroviruses occurred worldwide. Therefore, these neurotropic enteroviruses have been deemed as re-emerging pathogens. Although these viruses are becoming large threats to public health, our understanding of these viruses, especially for non-polio enteroviruses, is limited. In this article, we review recent advances in the trafficking of these pathogens from the peripheral to the central nervous system, compare their cell tropism, and discuss the effects of viral infections in their host neuronal cells.

Neurotropic Enterovirus Infections in the Central Nervous System

PubMed Central

Huang, Hsing-I; Shih, Shin-Ru

2015-01-01

Enteroviruses are a group of positive-sense single stranded viruses that belong to the Picornaviridae family. Most enteroviruses infect humans from the gastrointestinal tract and cause mild symptoms. However, several enteroviruses can invade the central nervous system (CNS) and result in various neurological symptoms that are correlated to mortality associated with enteroviral infections. In recent years, large outbreaks of enteroviruses occurred worldwide. Therefore, these neurotropic enteroviruses have been deemed as re-emerging pathogens. Although these viruses are becoming large threats to public health, our understanding of these viruses, especially for non-polio enteroviruses, is limited. In this article, we review recent advances in the trafficking of these pathogens from the peripheral to the central nervous system, compare their cell tropism, and discuss the effects of viral infections in their host neuronal cells. PMID:26610549

Aseptic Meningitis and Viral Myelitis

PubMed Central

Irani, David N.

2008-01-01

SYNOPSIS Meningitis and myelitis represent common and very infrequent viral infections of the central nervous system (CNS), respectively. Indeed, the number of cases of viral meningitis that occurs annually exceeds the total number of meningitis cases caused by all other etiologies combined. Focal CNS infections, on the other hand, such as occur in the spinal cord with viral myelitis, are much less common and may be confused with non-infectious disorders that cause acute flaccid paralysis (AFP). This chapter will review some of the important clinical features, epidemiology, diagnostic approaches, and management strategies for patients with aseptic meningitis and viral myelitis. Particular focus will be placed on the diseases caused by enteroviruses (EVs), which as a group account for the vast majority of all aseptic meningitis cases as well as many focal infections of the spinal cord. PMID:18657719

Transient urinary retention and chronic neuropathic pain associated with genital herpes simplex virus infection.

PubMed

Haanpää, Maija; Paavonen, Jorma

2004-10-01

Genital herpes (GH) causes genital ulcer disease, severe transient pain, and often paresthesias. Whether or not GH can cause urinary retention or chronic neuropathic pain is not well known. We present two immunocompetent patients with GH associated with neuropathic symptoms. We also review the literature on GH and associated neurologic problems. Patient 1 had primary herpes simplex virus (HSV)-2 infection with transient urinary retention and chronic bilateral neuropathic pain in the sacral area. Patient 2 had recurrent HSV-1 associated with unitaleral chronic neuropathic pain in the sacral area. Although transient urinary retention associated with GH is not uncommon, chronic neuropathic pain has not been reported previously. Our cases show that chronic neuropathic pain, that is "pain initiated or caused by a primary lesion or dysfunction in the nervous system," can follow genital HSV infection.

How Ebola virus counters the interferon system.

PubMed

Kühl, A; Pöhlmann, S

2012-09-01

Zoonotic transmission of Ebola virus (EBOV) to humans causes a severe haemorrhagic fever in afflicted individuals with high case-fatality rates. Neither vaccines nor therapeutics are at present available to combat EBOV infection, making the virus a potential threat to public health. To devise antiviral strategies, it is important to understand which components of the immune system could be effective against EBOV infection. The interferon (IFN) system constitutes a key innate defence against viral infections and prevents development of lethal disease in mice infected with EBOV strains not adapted to this host. Recent research revealed that expression of the host cell IFN-inducible transmembrane proteins 1-3 (IFITM1-3) and tetherin is induced by IFN and restricts EBOV infection, at least in cell culture model systems. IFITMs, tetherin and other effector molecules of the IFN system could thus pose a potent barrier against EBOV spread in humans. However, EBOV interferes with signalling events required for human cells to express these proteins. Here, we will review the strategies employed by EBOV to fight the IFN system, and we will discuss how IFITM proteins and tetherin inhibit EBOV infection. © 2012 Blackwell Verlag GmbH.

Innovative Methodology in the Discovery of Novel Drug Targets in the Free-Living Amoebae

PubMed

Baig, Abdul Mannan

2018-04-25

Despite advances in drug discovery and modifications in the chemotherapeutic regimens, human infections caused by free-living amoebae (FLA) have high mortality rates (~95%). The FLA that cause fatal human cerebral infections include Naegleria fowleri, Balamuthia mandrillaris and Acanthamoeba spp. Novel drug-target discovery remains the only viable option to tackle these central nervous system (CNS) infection in order to lower the mortality rates caused by the FLA. Of these FLA, N. fowleri causes primary amoebic meningoencephalitis (PAM), while the A. castellanii and B. Mandrillaris are known to cause granulomatous amoebic encephalitis (GAE). The infections caused by the FLA have been treated with drugs like Rifampin, Fluconazole, Amphotericin-B and Miltefosine. Miltefosine is an anti-leishmanial agent and an experimental anti-cancer drug. With only rare incidences of success, these drugs have remained unsuccessful to lower the mortality rates of the cerebral infection caused by FLA. Recently, with the help of bioinformatic computational tools and the discovered genomic data of the FLA, discovery of newer drug targets has become possible. These cellular targets are proteins that are either unique to the FLA or shared between the humans and these unicellular eukaryotes. The latter group of proteins has shown to be targets of some FDA approved drugs prescribed in non-infectious diseases. This review out-lines the bioinformatic methodologies that can be used in the discovery of such novel drug-targets, their chronicle by in-vitro assays done in the past and the translational value of such target discoveries in human diseases caused by FLA. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Monoassociation with probiotic Lactobacillus delbrueckii UFV-H2b20 stimulates the immune system and protects germfree mice against Listeria monocytogenes infection.

PubMed

dos Santos, Liliane Martins; Santos, Mônica Morais; de Souza Silva, Humberto Pereira; Arantes, Rosa Maria Esteves; Nicoli, Jacques Robert; Vieira, Leda Quercia

2011-02-01

In the present study, we investigated the protective effects of Lactobacillus delbrueckii UFV-H2b20 on the resistance to Listeria monocytogenes infection in gnotobiotic mice. Germfree mice or monoassociated mice were infected with L. monocytogenes, and the microbiological and immunological responses were evaluated after 1, 3, and 5 days of infection. Monoassociation with L. delbrueckii was capable of protecting mice against death caused by L. monocytogenes and induced a faster clearance of the bacteria in the liver, spleen, and peritoneal cavity at days 1, 3, and 5 post-infection. Also, monoassociated mice displayed less liver injury than germfree mice. The production of TNF-α in the serum, peritoneal cavity, and gut was augmented in monoassociated mice. Likewise, the levels of IFN-γ found on supernatants of spleen cells cultures were higher after the monoassociation. In addition, increased production of nitric oxide in peritoneal cell cultures supernatants and in serum was observed in mice that received L. delbrueckii. The monoassociation with L. delbrueckii induced higher production of IL-10 in the mucosal immune system. We conclude that monoassociation with L. delbrueckii UFV-H2b20 protects mice from death caused by L. monocytogenes infection by favoring effector responses while preventing their immunopathological consequences.

Sertoli Cells Are Susceptible to ZIKV Infection in Mouse Testis.

PubMed

Sheng, Zi-Yang; Gao, Na; Wang, Zhao-Yang; Cui, Xiao-Yun; Zhou, De-Shan; Fan, Dong-Ying; Chen, Hui; Wang, Pei-Gang; An, Jing

2017-01-01

Flaviviruses including Dengue virus (DENV), Yellow fever virus (YFV), West Nile virus (WNV), and Japanese encephalitis virus (JEV) are global health problems that caused several serious diseases such as fever, hemorrhagic fever, and encephalitis in the past century. Recently, Zika virus (ZIKV) which spreads from Asia to American and causes millions of infections emerges as a new dangerous member of the genus of Flavivirus . Unlike other well-known flaviviruses, ZIKV can be transmitted sexually and infect testes in murine models. Its impacts on sperm functions, and the exact susceptible cells, however, are not entirely clear. To investigate these issues, we infected interferon α/β and γ receptors deficient AG6 mice with ZIKV and examined the outcomes of infection using an assortment of physiological, histopathological, immunological, and virological techniques. We found that infected mice displayed signs of reproductive system disorder, altered androgen levels in serum, and high viral load in semen and testes. Additionally, histopathological examinations revealed marked atrophy of seminiferous tubules and significant reduction in lumen size. Notably, these were accompanied by positive staining of ZIKV antigens on sertoli cells, detection of viral particles and vacuole changes within cytoplasm of sertoli cells. The susceptibility of sertoli cells to ZIKV was further validated in vitro study using cell lines. Importantly, the disruption of tight junctions within testis and altered sperm morphology were also observed in ZIKV infected mice. It is well-known that tight junctions formed by adjacent sertoli cells are major component of blood testis barrier, which plays important roles in maintenance of microenvironment for spermagenesis in testis. Taken together, these results demonstrate that sertoli cells are susceptible to ZIKV infection, which results in the disruption of tight junctions in testis and causes abnormal spermatogenesis in mice. These results also imply that long-term impact of ZIKV infection on human male reproductive system requires close monitoring.

Experimental infection with Haemophilus ducreyi in persons who are infected with HIV does not cause local or augment systemic viral replication.

PubMed

Janowicz, Diane M; Tenner-Racz, Klara; Racz, Paul; Humphreys, Tricia L; Schnizlein-Bick, Carol; Fortney, Kate R; Zwickl, Beth; Katz, Barry P; Campbell, James J; Ho, David D; Spinola, Stanley M

2007-05-15

We infected 11 HIV-seropositive volunteers whose CD4(+) cell counts were >350 cells/ microL (7 of whom were receiving antiretrovirals) with Haemophilus ducreyi. The papule and pustule formation rates were similar to those observed in HIV-seronegative historical control subjects. No subject experienced a sustained change in CD4(+) cell count or HIV RNA level. The cellular infiltrate in biopsy samples obtained from the HIV-seropositive and HIV-seronegative subjects did not differ with respect to the percentage of leukocytes, neutrophils, macrophages, or T cells. The CD4(+):CD8(+) cell ratio in biopsy samples from the HIV-seropositive subjects was 1:3, the inverse of the ratio seen in the HIV-seronegative subjects (P<.0001). Although CD4(+) cells proliferated in lesions, in situ hybridization and reverse-transcription polymerase chain reaction for HIV RNA was negative. We conclude that experimental infection in HIV-seropositive persons is clinically similar to infection in HIV-seronegative persons and does not cause local or augment systemic viral replication. Thus, prompt treatment of chancroid may abrogate increases in viral replication associated with natural disease.

New Insights into Gastrointestinal Anthrax Infection

PubMed Central

Owen, Jennifer L.; Yang, Tao; Mohamadzadeh, Mansour

2014-01-01

Bacterial infections are the primary cause of gastrointestinal (GI) disorders in both developing and developed countries, and are particularly dangerous for infants and children. Bacillus anthracis is the “archetype zoonotic” pathogen; no other infectious disease affects such a broad range of species, including humans. Importantly, there are more case reports of GI anthrax infection in children than inhalational disease. Early diagnosis is difficult and widespread systemic disease develops rapidly. This review highlights new findings concerning the roles of the gut epithelia, commensal microbiota, and innate lymphoid cells in initiation of disease and systemic dissemination in animal models of GI anthrax, the understanding of which is crucial to designing alternative therapies that target establishment of infection. PMID:25577136

Infective Causes of Epilepsy.

PubMed

Bonello, M; Michael, B D; Solomon, T

2015-06-01

A wide range of infections of the central nervous system are responsible for both acute seizures and epilepsy. The pathogenesis and clinical semiology of the seizure disorders vary widely between the infective pathogens. The exact mechanisms underlying this are poorly understood, but appear, at least in part, to relate to the pathogen; the degree of cortical involvement; delays in treatment; and the host inflammatory response. The treatment of infective causes of seizures involves both symptomatic treatment with antiepileptic drugs and direct treatment of the underlying condition. In many cases, early treatment of the infection may affect the prognosis of the epilepsy syndrome. The greatest burden of acute and long-term infection-related seizures occurs in resource-poor settings, where both clinical and research facilities are often lacking to manage such patients adequately. Nevertheless, education programs may go a long way toward addressing the stigma, leading to improved diagnosis, management, and ultimately to better quality of life. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Streptococcal toxic shock syndrome secondary to group A Streptococcus vaginitis.

PubMed

Hikone, Mayu; Kobayashi, Ken-Ichiro; Washino, Takuya; Ota, Masayuki; Sakamoto, Naoya; Iwabuchi, Sentaro; Ohnishi, Kenji

2015-12-01

Streptococcal toxic shock syndrome (TSS) is a systemic illness usually caused in the setting of infection by group A Streptococcus (GAS). The primary infections are often invasive infections of the respiratory tract or necrotizing infections of the skin and soft tissue, but some infections occur without relevant focus. GAS vaginitis is a rare condition among adult women and is accordingly thought to be uncommon as a cause of streptococcal TSS. Here we report the cases of two postmenopausal women with streptococcal TSS secondary to GAS vaginitis, one aged 55 and one aged 60. Both came to our emergency department with complaints or symptoms of abdominal pain, fever, hypotension, and multi-organ failure. In both cases, the relevant factor associated with streptococcal infection was a recent episode of GAS vaginitis. Both underwent fluid management and 14 days of antibiotic treatment and fully recovered without complications. Vaginitis was likely to be the primary infectious trigger of TSS in these two cases. Intrauterine device insertion, endometrial biopsy, and post-partum state have all been previously reported in TSS patients, and the female genital tract has been described as a portal of entry. GAS vaginitis warrants appropriate treatment as it may progress to severe systemic infection as described. Copyright © 2015 Japanese Society of Chemotherapy and The Japanese Association for Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

Aspergillus--classification and antifungal susceptibilities.

PubMed

Buzina, Walter

2013-01-01

Aspergillus is one of the most important fungal genera for the man, for its industrial use, its ability to spoil food and not least its medical impact as cause of a variety of diseases. Currently hundreds of species of Aspergillus are known; nearly fifty of them are able to cause infections in humans and animals. Recently, the genus Aspergillus is subdivided into 8 subgenera and 22 sections. The spectrum of diseases caused by Aspergillus species varies from superficial cutaneous to invasive and systemic infections. All species of Aspergillus investigated so far are resistant against the antifungals fluconazole and 5-fluorocytosine, the range of susceptibilities to currently available antifungals is discussed in this paper.

Chronic Trichuris muris infection causes neoplastic change in the intestine and exacerbates tumour formation in APC min/+ mice

PubMed Central

Cliffe, Laura J.; Bancroft, Alison J.; Forman, Simon P.; Thompson, Seona; Booth, Cath

2017-01-01

Incidences of infection-related cancers are on the rise in developing countries where the prevalence of intestinal nematode worm infections are also high. Trichuris muris (T. muris) is a murine gut-dwelling nematode that is the direct model for human T. trichiura, one of the major soil-transmitted helminth infections of humans. In order to assess whether chronic infection with T. muris does indeed influence the development of cancer hallmarks, both wild type mice and colon cancer model (APC min/+) mice were infected with this parasite. Parasite infection in wild type mice led to the development of neoplastic change similar to that seen in mice that had been treated with the carcinogen azoxymethane. Additionally, both chronic and acute infection in the APCmin/+ mice led to an enhanced tumour development that was distinct to the site of infection suggesting systemic control. By blocking the parasite induced T regulatory response in these mice, the increase in the number of tumours following infection was abrogated. Thus T. muris infection alone causes an increase in gut pathologies that are known to be markers of cancer but also increases the incidence of tumour formation in a colon cancer model. The influence of parasitic worm infection on the development of cancer may therefore be significant. PMID:28650985

Chronic Trichuris muris infection causes neoplastic change in the intestine and exacerbates tumour formation in APC min/+ mice.

PubMed

Hayes, Kelly S; Cliffe, Laura J; Bancroft, Alison J; Forman, Simon P; Thompson, Seona; Booth, Cath; Grencis, Richard K

2017-06-01

Incidences of infection-related cancers are on the rise in developing countries where the prevalence of intestinal nematode worm infections are also high. Trichuris muris (T. muris) is a murine gut-dwelling nematode that is the direct model for human T. trichiura, one of the major soil-transmitted helminth infections of humans. In order to assess whether chronic infection with T. muris does indeed influence the development of cancer hallmarks, both wild type mice and colon cancer model (APC min/+) mice were infected with this parasite. Parasite infection in wild type mice led to the development of neoplastic change similar to that seen in mice that had been treated with the carcinogen azoxymethane. Additionally, both chronic and acute infection in the APCmin/+ mice led to an enhanced tumour development that was distinct to the site of infection suggesting systemic control. By blocking the parasite induced T regulatory response in these mice, the increase in the number of tumours following infection was abrogated. Thus T. muris infection alone causes an increase in gut pathologies that are known to be markers of cancer but also increases the incidence of tumour formation in a colon cancer model. The influence of parasitic worm infection on the development of cancer may therefore be significant.

On the causes of persistent apical periodontitis: a review.

PubMed

Nair, P N R

2006-04-01

Apical periodontitis is a chronic inflammatory disorder of periradicular tissues caused by aetiological agents of endodontic origin. Persistent apical periodontitis occurs when root canal treatment of apical periodontitis has not adequately eliminated intraradicular infection. Problems that lead to persistent apical periodontitis include: inadequate aseptic control, poor access cavity design, missed canals, inadequate instrumentation, debridement and leaking temporary or permanent restorations. Even when the most stringent procedures are followed, apical periodontitis may still persist as asymptomatic radiolucencies, because of the complexity of the root canal system formed by the main and accessory canals, their ramifications and anastomoses where residual infection can persist. Further, there are extraradicular factors -- located within the inflamed periapical tissue -- that can interfere with post-treatment healing of apical periodontitis. The causes of apical periodontitis persisting after root canal treatment have not been well characterized. During the 1990s, a series of investigations have shown that there are six biological factors that lead to asymptomatic radiolucencies persisting after root canal treatment. These are: (i) intraradicular infection persisting in the complex apical root canal system; (ii) extraradicular infection, generally in the form of periapical actinomycosis; (iii) extruded root canal filling or other exogenous materials that cause a foreign body reaction; (iv) accumulation of endogenous cholesterol crystals that irritate periapical tissues; (v) true cystic lesions, and (vi) scar tissue healing of the lesion. This article provides a comprehensive overview of the causative factors of non-resolving periapical lesions that are seen as asymptomatic radiolucencies post-treatment.

Coccidioidomycosis and other endemic mycoses in Mexico.

PubMed

Laniado-Laborín, Rafael

2007-12-31

The endemic mycoses traditionally include coccidioidomycosis, histoplasmosis, blastomycosis and paracoccidioidomycosis. Although sporotrichosis and chromomycosis are technically not included among the endemic mycoses, they are frequently diagnosed in Mexico. Most systemic endemic mycoses are a consequence of inhaling the fungi, while subcutaneous mycoses are acquired through the inoculation of vegetable matter or soil containing the organism. Coccidioidomycosis is caused by Coccidioides spp., a dimorphic pathogenic fungus. Approximately 60% of exposures result in asymptomatic infection; in the rest there are protean manifestations that range from a benign syndrome also known as "Valley Fever" to progressive pulmonary or extrapulmonary disease. Histoplasmosis, caused by the dimorphic fungus Histoplasma capsulatum, is endemic to the Americas. Pulmonary histoplasmosis manifestations are protean, ranging from a brief period of malaise to a severe, prolonged illness. The spectrum of illness in disseminated histoplasmosis ranges from a chronic, intermittent course to an acute and rapidly fatal infection. Paracoccidioidomycosis is a chronic, granulomatous systemic disease caused by Paracoccidioides brasiliensis that characteristically produces a primary pulmonary infection, often asymptomatic, and then disseminates to form ulcerative granulomata of the oral, nasal and occasionally the gastrointestinal mucosa. Sporotrichosis, caused by Sporothrix schenckii, has diverse clinical manifestations; the most frequent is the lymphocutaneous form. Generally, infection results from inoculation of the fungus through thorns, splinters, scratches and small traumas. Chromomycosis (Chromoblastomycosis) is a slowly progressive cutaneous and subcutaneous mycosis attributed to various saprophyte Hypomycetes fungi. The primary lesion is also thought to develop as a result of percutaneous traumatic inoculation.

Nucleotide and nucleoside involvement in immunomodulation in experimental Chagas disease.

PubMed

do Carmo, Guilherme M; de Sá, Mariângela F; Baldissera, Matheus D; Grando, Thirssa H; Mendes, Ricardo E; Cardoso, Valesca V; Casali, Emerson A; Moritz, Cesar Eduardo J; Monteiro, Silvia G; Da Silva, Aleksandro S

2018-02-05

The aim of this study was to evaluate whether Trypanosma cruzi infections cause alterations in the levels of seric purines, which could contribute to host immunomodulation. Twelve mice were divided into two groups identified as control (uninfected) and infected (T. cruzi) groups. The influence of the disease on seric purine levels was verified on day 20 post-infection (PI) by HPLC. Infected mice had circulating trypomastigotes during the experiment, as well as amastigote forms in the heart associated with inflammatory infiltrates. Increases on adenosine triphosphate (ATP), adenosine diphosphate (ADP), adenosine (ADO), inosine (INO), and uric acid (URIC) levels were observed in the infected animals, while the adenosine monophosphate (AMP) and xanthine (XAN) levels were reduced compared with mice of the control group, indicating a possible impairment on the purinergic system, and consequently, on the immune system during the clinical course of the disease. In summary, the T. cruzi infection alters the seric purine levels, and consequently, modulates the immune system.

Iridovirus infections in farm-reared tropical ornamental fish.

PubMed

Paperna, I; Vilenkin, M; de Matos, A P

2001-12-20

A systemic viral infection in both gourami Trichogaster spp. and swordtail Xiphophorus hellerii and an outbreak of lymphocystis in scalare Pterophyllum scalarae and gourami are reported to have occurred in fish reared in ornamental fish farms in Israel. The systemic infection developed in endothelial cells that became hypertrophic and their contents were modified. The presence of such cells in light-microscopically examined stained smears and sections provides an initial indication for this systemic viral infection. Infection in gourami caused hemorrhagic dropsy. Transmission electron microscopic (TEM) images of iridovirus-like particles recovered from gouramies showed them to be 138 to 201 nm from vertex to vertex (v-v); those from swordtails were 170 to 188 nm v-v. TEM images of lymphocystis virions from scalare were 312 to 342 nm v-v and from gourami 292 to 341 nm v-v. Lymphocystis cells from the gourami were joined by a solid hyaline plate, which was lacking in the infection in scalare where the intercellular spaces between the lymphocystis cells consisted of loose connective tissue.

Systems immunology reveals markers of susceptibility to West Nile virus infection.

PubMed

Qian, Feng; Goel, Gautam; Meng, Hailong; Wang, Xiaomei; You, Fuping; Devine, Lesley; Raddassi, Khadir; Garcia, Melissa N; Murray, Kristy O; Bolen, Christopher R; Gaujoux, Renaud; Shen-Orr, Shai S; Hafler, David; Fikrig, Erol; Xavier, Ramnik; Kleinstein, Steven H; Montgomery, Ruth R

2015-01-01

West Nile virus (WNV) infection is usually asymptomatic but can cause severe neurological disease and death, particularly in older patients, and how individual variations in immunity contribute to disease severity is not yet defined. Animal studies identified a role for several immunity-related genes that determine the severity of infection. We have integrated systems-level transcriptional and functional data sets from stratified cohorts of subjects with a history of WNV infection to define whether these markers can distinguish susceptibility in a human population. Transcriptional profiles combined with immunophenotyping of primary cells identified a predictive signature of susceptibility that was detectable years after acute infection (67% accuracy), with the most prominent alteration being decreased IL1B induction following ex vivo infection of macrophages with WNV. Deconvolution analysis also determined a significant role for CXCL10 expression in myeloid dendritic cells. This systems analysis identified markers of pathogenic mechanisms and offers insights into potential therapeutic strategies. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

Human Fungal Pathogens of Mucorales and Entomophthorales.

PubMed

Mendoza, Leonel; Vilela, Raquel; Voelz, Kerstin; Ibrahim, Ashraf S; Voigt, Kerstin; Lee, Soo Chan

2014-11-06

In recent years, we have seen an increase in the number of immunocompromised cohorts as a result of infections and/or medical conditions, which has resulted in an increased incidence of fungal infections. Although rare, the incidence of infections caused by fungi belonging to basal fungal lineages is also continuously increasing. Basal fungal lineages diverged at an early point during the evolution of the fungal lineage, in which, in a simplified four-phylum fungal kingdom, Zygomycota and Chytridiomycota belong to the basal fungi, distinguishing them from Ascomycota and Basidiomycota. Currently there are no known human infections caused by fungi in Chytridiomycota; only Zygomycotan fungi are known to infect humans. Hence, infections caused by zygomycetes have been called zygomycosis, and the term "zygomycosis" is often used as a synonym for "mucormycosis." In the four-phylum fungal kingdom system, Zygomycota is classified mainly based on morphology, including the ability to form coenocytic (aseptated) hyphae and zygospores (sexual spores). In the Zygomycota, there are 10 known orders, two of which, the Mucorales and Entomophthorales, contain species that can infect humans, and the infection has historically been known as zygomycosis. However, recent multilocus sequence typing analyses (the fungal tree of life [AFTOL] project) revealed that the Zygomycota forms not a monophyletic clade but instead a polyphyletic clade, whereas Ascomycota and Basidiomycota are monophyletic. Thus, the term "zygomycosis" needed to be further specified, resulting in the terms "mucormycosis" and "entomophthoramycosis." This review covers these two different types of fungal infections. Copyright © 2015 Cold Spring Harbor Laboratory Press; all rights reserved.

Human Fungal Pathogens of Mucorales and Entomophthorales

PubMed Central

Mendoza, Leonel; Vilela, Raquel; Voelz, Kerstin; Ibrahim, Ashraf S.; Voigt, Kerstin; Lee, Soo Chan

2015-01-01

In recent years, we have seen an increase in the number of immunocompromised cohorts as a result of infections and/or medical conditions, which has resulted in an increased incidence of fungal infections. Although rare, the incidence of infections caused by fungi belonging to basal fungal lineages is also continuously increasing. Basal fungal lineages diverged at an early point during the evolution of the fungal lineage, in which, in a simplified four-phylum fungal kingdom, Zygomycota and Chytridiomycota belong to the basal fungi, distinguishing them from Ascomycota and Basidiomycota. Currently there are no known human infections caused by fungi in Chytridiomycota; only Zygomycotan fungi are known to infect humans. Hence, infections caused by zygomycetes have been called zygomycosis, and the term “zygomycosis” is often used as a synonym for “mucormycosis.” In the four-phylum fungal kingdom system, Zygomycota is classified mainly based on morphology, including the ability to form coenocytic (aseptated) hyphae and zygospores (sexual spores). In the Zygomycota, there are 10 known orders, two of which, the Mucorales and Entomophthorales, contain species that can infect humans, and the infection has historically been known as zygomycosis. However, recent multilocus sequence typing analyses (the fungal tree of life [AFTOL] project) revealed that the Zygomycota forms not a monophyletic clade but instead a polyphyletic clade, whereas Ascomycota and Basidiomycota are monophyletic. Thus, the term “zygomycosis” needed to be further specified, resulting in the terms “mucormycosis” and “entomophthoramycosis.” This review covers these two different types of fungal infections. PMID:25377138

Adenovirus vector infection of non-small-cell lung cancer cells is a trigger for multi-drug resistance mediated by P-glycoprotein.

PubMed

Tomono, Takumi; Kajita, Masahiro; Yano, Kentaro; Ogihara, Takuo

2016-08-05

P-glycoprotein (P-gp) is an ATP-binding cassette protein involved in cancer multi-drug resistance (MDR). It has been reported that infection with some bacteria and viruses induces changes in the activities of various drug-metabolizing enzymes and transporters, including P-gp. Although human adenoviruses (Ad) cause the common cold, the effect of Ad infection on MDR in cancer has not been established. In this study, we investigated whether Ad infection is a cause of MDR in A549, H441 and HCC827 non-small-cell lung cancer (NSCLC) cell lines, using an Ad vector system. We found that Ad vector infection of NSCLC cell lines induced P-gp mRNA expression, and the extent of induction was dependent on the number of Ad vector virus particles and the infection time. Heat-treated Ad vector, which is not infectious, did not alter P-gp mRNA expression. Uptake experiments with doxorubicin (DOX), a P-gp substrate, revealed that DOX accumulation was significantly decreased in Ad vector-infected A549 cells. The decrease of DOX uptake was blocked by verapamil, a P-gp inhibitor. Our results indicated that Ad vector infection of NSCLC cells caused MDR mediated by P-gp overexpression. The Ad vector genome sequence is similar to that of human Ad, and therefore human Ad infection of lung cancer patients may lead to chemoresistance in the clinical environment. Copyright © 2016 Elsevier Inc. All rights reserved.

A review of the critical role of vitamin D in the functioning of the immune system and the clinical implications of vitamin D deficiency.

PubMed

Schwalfenberg, Gerry K

2011-01-01

This review looks at the critical role of vitamin D in improving barrier function, production of antimicrobial peptides including cathelicidin and some defensins, and immune modulation. The function of vitamin D in the innate immune system and in the epithelial cells of the oral cavity, lung, gastrointestinal system, genito-urinary system, skin and surface of the eye is discussed. Clinical conditions are reviewed where vitamin D may play a role in the prevention of infections or where it may be used as primary or adjuvant treatment for viral, bacterial and fungal infections. Several conditions such as tuberculosis, psoriasis, eczema, Crohn's disease, chest infections, wound infections, influenza, urinary tract infections, eye infections and wound healing may benefit from adequate circulating 25(OH)D as substrate. Clinical diseases are presented in which optimization of 25(OH)D levels may benefit or cause harm according to present day knowledge. The safety of using larger doses of vitamin D in various clinical settings is discussed. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Link between cutaneous infection, stress and depression.

PubMed

Jagmag, T; Tirant, M; Lotti, T

2017-01-01

Depression and mood disorders often develop after dermatological conditions which could be primary or secondary to dermatological pathology. The oxidative and psychological stress cause physiological changes in the body. Shift in the methylation pathway, elevated cortisol, lowered neurotransmitter levels and lowered immune system allow infection to penetrate the body and lead to anxiety and depression. Here, a case report of a 20 year old male patient is presented to show how infectious skin lesions, unresponsive to the usual treatment plan, were treated after using a multipronged approach of addressing systemic infection of Escherichia coli, elevated cortisol levels and nutritional imbalances.

Systemic chlorellosis, an emerging infection in humans caused by algae.

PubMed

Krcméry, V

2000-08-01

One hundred and eight cases of human protothecosis occurring over 25 years are reviewed. The most common species isolated was Prototheca wickerhamii, The algae have been isolated from a large number of sites but seem to have low virulence. In the majority of systemic infections there have been few symptoms. Cutaneous manifestations may vary from patient to patient but infections of immunosuppressed patients tend to be more florid. Most cases have been successfully treated by excising the lesion or with antifungals. Most strains are sensitive to 5-fluorocytosine, amphotericin B and the azoles but resistance does occur.

Treatment strategies for Aspergillus infections.

PubMed

Chiller, Tom M.; Stevens, David A.

2000-04-01

Infections caused by Aspergillus species consist of many different disease presentations, ranging from relatively benign asthma in atopic disease to life-threatening systemic invasive infections. The spectrum of disease manifestations is determined by a combination of genetic predisposition, host immune system defects, and virulence of the Aspergillus species. For the purposes of this discussion, we will address three principal entities: invasive aspergillosis, both primary and disseminated, pulmonary aspergilloma, and allergic bronchopulmonary aspergillosis. Amphotericin B is the standard of treatment for severe Aspergillus infections, despite the fact that mortality in these patients remains high. Alternative therapies such as combination regimens and itraconazole also have efficacy against Aspergillus infections. We discuss the role of current therapies, the potential role of drugs in development, and the results of ongoing research with combination and immunotherapies. Copyright 2000 Harcourt Publishers Ltd.

Apoptosis Modulation in the Immune System Reveals a Role of Neutrophils in Tissue Damage in a Murine Model of Chlamydial Genital Infection.

PubMed

Zortel, Tom; Schmitt-Graeff, Annette; Kirschnek, Susanne; Häcker, Georg

2018-05-05

Chlamydial infection frequently causes damage to the female genital tract. The precise mechanisms of chlamydial clearance and tissue damage are unknown, but studies suggest immunopathology with a particular role of neutrophils. The goal of this study was to understand the contribution of the immune system, in particular neutrophils. Using Chlamydia muridarum, we infected mice with a prolonged immune response due to expression of B-cell lymphoma 2 (Bcl-2) in hematopoietic cells (Bcl-2 mice), and mice where mature neutrophils are lacking due to the deletion of Myeloid cell leukemia 1 (Mcl-1) in myeloid cells (LysM-cre-mcl-1-flox mice; Mcl-1 mice). We monitored bacterial clearance, cellular infiltrate, and long-term tissue damage. Both mutant strains showed slightly delayed clearance of the acute infection. Bcl-2 mice had a strongly increased inflammatory infiltrate concerning almost all cell lineages. The infection of Bcl-2 mice caused increased tissue damage. The loss of neutrophils in Mcl-1 mice was associated with substantial quantitative and qualitative alterations of the inflammatory infiltrate. Mcl-1 mice had higher chlamydial burden and reduced tissue damage, including lower incidence of hydrosalpinx and less uterine dilation. Inhibition of apoptosis in the hematopoietic system increases inflammation and tissue damage. Neutrophils have broad functions, including a role in chlamydial clearance and in tissue destruction.

Mechanisms underlying zoonotic success of Campylobacter jejuni: the CprRS two-component regulatory system influences essential processes, biofilm formation, and pathogenesis

USDA-ARS?s Scientific Manuscript database

Campylobacter jejuni is a leading cause of food- and waterbourne bacterial gastroenteritis in the developed world. Although illness is usually self-limiting, immunocompromised individuals are at risk for infections recalcitrant to antibiotic treatment, and prior campylobacter infection correlates wi...

Health Wise: March 2010

ERIC Educational Resources Information Center

Streker, Meg

2010-01-01

In this article, the author discusses how to tell the difference between a cold and airborne allergy symptoms. A cold is caused by a viral infection. Viruses spread through an infected person's cough, sneeze, handshake, or contact with a contaminated surface. When a virus enters one's body, his/her immune system reacts. This produces the symptoms…

A pathogenesis assay using Saccharomyces cerevisiae and Caenorhabditis elegans reveals novel roles for yeast AP-1, Yap1, and host dual oxidase BLI-3 in fungal pathogenesis.

PubMed

Jain, Charu; Yun, Meijiang; Politz, Samuel M; Rao, Reeta Prusty

2009-08-01

Treatment of systemic fungal infections is difficult because of the limited number of antimycotic drugs available. Thus, there is an immediate need for simple and innovative systems to assay the contribution of individual genes to fungal pathogenesis. We have developed a pathogenesis assay using Caenorhabditis elegans, an established model host, with Saccharomyces cerevisiae as the invading fungus. We have found that yeast infects nematodes, causing disease and death. Our data indicate that the host produces reactive oxygen species (ROS) in response to fungal infection. Yeast mutants sod1Delta and yap1Delta, which cannot withstand ROS, fail to cause disease, except in bli-3 worms, which carry a mutation in a dual oxidase gene. Chemical inhibition of the NADPH oxidase activity abolishes ROS production in worms exposed to yeast. This pathogenesis assay is useful for conducting systematic, whole-genome screens to identify fungal virulence factors as alternative targets for drug development and exploration of host responses to fungal infections.

Congenital cytomegalovirus infection: an obstetrician's point of view.

PubMed

Soper, David E

2013-12-01

Maternal cytomegalovirus (CMV) is the cause of the most frequent congenital infection in America; however, pregnant women are not routinely screened. Primary CMV infection is associated with a high maternal-to-child transmission rate (40%); up to 15% of these infected neonates will be symptomatic at birth and develop permanent sequelae that usually involve the central nervous system. New interventions are now available to decrease the rate of primary maternal infection as well as to treat pregnant women with primary infection, thus decreasing the fetal and neonatal morbidity associated with this disease. Based on these data, strategies for maternal screening need to be reconsidered.

[Aspects of the innate immune response to intramammary Staphylococcus aureus infections in cattle].

PubMed

Pereyra, Elizabet A L; Dallard, Bibiana E; Calvinho, Luis F

2014-01-01

Staphylococcus aureus is the pathogen most frequently isolated from bovine mastitis worldwide, causing chronic intramammary infections that limit profitable dairying. The objective of this article is to characterize the mechanisms involved in S. aureus mammary gland infections considering two different aspects of the infectious process; on the one hand, the aspects involved in the host innate immune response and on the other hand, the capacity of this organism to evade the immune system and interact with different cell types. The exploration of S. aureus interactions with the immune response of bovine mammary gland will help identify targets to outline new preventive or curative alternatives for intramammary infections caused by this organism. Copyright © 2014 Asociación Argentina de Microbiología. Publicado por Elsevier España. All rights reserved.

The Regulatory Networks That Control Clostridium difficile Toxin Synthesis

PubMed Central

Martin-Verstraete, Isabelle; Peltier, Johann; Dupuy, Bruno

2016-01-01

The pathogenic clostridia cause many human and animal diseases, which typically arise as a consequence of the production of potent exotoxins. Among the enterotoxic clostridia, Clostridium difficile is the main causative agent of nosocomial intestinal infections in adults with a compromised gut microbiota caused by antibiotic treatment. The symptoms of C. difficile infection are essentially caused by the production of two exotoxins: TcdA and TcdB. Moreover, for severe forms of disease, the spectrum of diseases caused by C. difficile has also been correlated to the levels of toxins that are produced during host infection. This observation strengthened the idea that the regulation of toxin synthesis is an important part of C. difficile pathogenesis. This review summarizes our current knowledge about the regulators and sigma factors that have been reported to control toxin gene expression in response to several environmental signals and stresses, including the availability of certain carbon sources and amino acids, or to signaling molecules, such as the autoinducing peptides of quorum sensing systems. The overlapping regulation of key metabolic pathways and toxin synthesis strongly suggests that toxin production is a complex response that is triggered by bacteria in response to particular states of nutrient availability during infection. PMID:27187475

Rotavirus infection

PubMed Central

Crawford, Sue E.; Ramani, Sasirekha; Tate, Jacqueline E.; Parashar, Umesh D.; Svensson, Lennart; Hagbom, Marie; Franco, Manuel A.; Greenberg, Harry B.; O’Ryan, Miguel; Kang, Gagandeep; Desselberger, Ulrich; Estes, Mary K.

2017-01-01

Rotavirus infections are a leading cause of severe, dehydrating gastroenteritis in children <5 years of age. Despite the global introduction of vaccinations for rotavirus over a decade ago, rotavirus infections still result in >200,000 deaths annually, mostly in low-income countries. Rotavirus primarily infects enterocytes and induces diarrhoea through the destruction of absorptive enterocytes (leading to malabsorption), intestinal secretion stimulated by rotavirus non-structural protein 4 and activation of the enteric nervous system. In addition, rotavirus infections can lead to antigenaemia (which is associated with more severe manifestations of acute gastroenteritis) and viraemia, and rotavirus can replicate in systemic sites, although this is limited. Reinfections with rotavirus are common throughout life, although the disease severity is reduced with repeat infections. The immune correlates of protection against rotavirus reinfection and recovery from infection are poorly understood, although rotavirus-specific immunoglobulin A has a role in both aspects. The management of rotavirus infection focuses on the prevention and treatment of dehydration, although the use of antiviral and anti-emetic drugs can be indicated in some cases. PMID:29119972

Salmonella infections associated with international travel: a Foodborne Diseases Active Surveillance Network (FoodNet) study.

PubMed

Johnson, Laura R; Gould, L Hannah; Dunn, John R; Berkelman, Ruth; Mahon, Barbara E

2011-09-01

Salmonella species cause an estimated 1.2 million infections per year in the United States, making it one of the most commonly reported enteric pathogens. In addition, Salmonella is an important cause of travel-associated diarrhea and enteric fever, a systemic illness commonly associated with Salmonella serotypes Typhi and Paratyphi A. We reviewed cases of Salmonella infection reported to the Centers for Disease Control and Prevention's (CDC) Foodborne Diseases Active Surveillance Network (FoodNet), a sentinel surveillance network, from 2004 to 2008. We compared travelers with Salmonella infection to nontravelers with Salmonella infection with respect to demographics, clinical characteristics, and serotypes. Among 23,712 case-patients with known travel status, 11% had traveled internationally in the 7 days before illness. Travelers with Salmonella infection tended to be older (median age, 30 years) than nontravelers (median age, 24 years; p<0.0001), but were similar with respect to gender. The most common destinations reported were Mexico (38% of travel-associated infections), India (9%), Jamaica (7%), the Dominican Republic (4%), China (3%), and the Bahamas (2%). The proportions of travelers with Salmonella infection hospitalized and with invasive disease were inversely related to the income level of the destination (p<0.0001). The most commonly reported serotypes, regardless of travel status, were Enteritidis (19% of cases), Typhimurium (14%), Newport (9%), and Javiana (5%). Among infections caused by these four serotypes, 22%, 6%, 5%, and 4%, respectively, were associated with travel. A high index of clinical suspicion for Salmonella infection is appropriate when evaluating recent travelers, especially those who visited Africa, Asia, or Latin America.

Species-Level Identification of Actinomyces Isolates Causing Invasive Infections: Multiyear Comparison of Vitek MS (Matrix-Assisted Laser Desorption Ionization-Time of Flight Mass Spectrometry) to Partial Sequencing of the 16S rRNA Gene.

PubMed

Lynch, T; Gregson, D; Church, D L

2016-03-01

Actinomyces species are uncommon but important causes of invasive infections. The ability of our regional clinical microbiology laboratory to report species-level identification of Actinomyces relied on molecular identification by partial sequencing of the 16S ribosomal gene prior to the implementation of the Vitek MS (matrix-assisted laser desorption ionization-time of flight mass spectrometry [MALDI-TOF MS]) system. We compared the use of the Vitek MS to that of 16S rRNA gene sequencing for reliable species-level identification of invasive infections caused by Actinomyces spp. because limited data had been published for this important genera. A total of 115 cases of Actinomyces spp., either alone or as part of a polymicrobial infection, were diagnosed between 2011 and 2014. Actinomyces spp. were considered the principal pathogen in bloodstream infections (n = 17, 15%), in skin and soft tissue abscesses (n = 25, 22%), and in pulmonary (n = 26, 23%), bone (n = 27, 23%), intraabdominal (n = 16, 14%), and central nervous system (n = 4, 3%) infections. Compared to sequencing and identification from the SmartGene Integrated Database Network System (IDNS), Vitek MS identified 47/115 (41%) isolates to the correct species and 10 (9%) isolates to the correct genus. However, the Vitek MS was unable to provide identification for 43 (37%) isolates while 15 (13%) had discordant results. Phylogenetic analyses of the 16S rRNA sequences demonstrate high diversity in recovered Actinomyces spp. and provide additional information to compare/confirm discordant identifications between MALDI-TOF and 16S rRNA gene sequences. This study highlights the diversity of clinically relevant Actinomyces spp. and provides an important typing comparison. Based on our analysis, 16S rRNA gene sequencing should be used to rapidly identify Actinomyces spp. until MALDI-TOF databases are optimized. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

Species-Level Identification of Actinomyces Isolates Causing Invasive Infections: Multiyear Comparison of Vitek MS (Matrix-Assisted Laser Desorption Ionization–Time of Flight Mass Spectrometry) to Partial Sequencing of the 16S rRNA Gene

PubMed Central

Gregson, D.; Church, D. L.

2016-01-01

Actinomyces species are uncommon but important causes of invasive infections. The ability of our regional clinical microbiology laboratory to report species-level identification of Actinomyces relied on molecular identification by partial sequencing of the 16S ribosomal gene prior to the implementation of the Vitek MS (matrix-assisted laser desorption ionization–time of flight mass spectrometry [MALDI-TOF MS]) system. We compared the use of the Vitek MS to that of 16S rRNA gene sequencing for reliable species-level identification of invasive infections caused by Actinomyces spp. because limited data had been published for this important genera. A total of 115 cases of Actinomyces spp., either alone or as part of a polymicrobial infection, were diagnosed between 2011 and 2014. Actinomyces spp. were considered the principal pathogen in bloodstream infections (n = 17, 15%), in skin and soft tissue abscesses (n = 25, 22%), and in pulmonary (n = 26, 23%), bone (n = 27, 23%), intraabdominal (n = 16, 14%), and central nervous system (n = 4, 3%) infections. Compared to sequencing and identification from the SmartGene Integrated Database Network System (IDNS), Vitek MS identified 47/115 (41%) isolates to the correct species and 10 (9%) isolates to the correct genus. However, the Vitek MS was unable to provide identification for 43 (37%) isolates while 15 (13%) had discordant results. Phylogenetic analyses of the 16S rRNA sequences demonstrate high diversity in recovered Actinomyces spp. and provide additional information to compare/confirm discordant identifications between MALDI-TOF and 16S rRNA gene sequences. This study highlights the diversity of clinically relevant Actinomyces spp. and provides an important typing comparison. Based on our analysis, 16S rRNA gene sequencing should be used to rapidly identify Actinomyces spp. until MALDI-TOF databases are optimized. PMID:26739153

In vitro and in vivo cell invasion and systemic spreading of Mycoplasma agalactiae in the sheep infection model.

PubMed

Hegde, Shivanand; Hegde, Shrilakshmi; Spergser, Joachim; Brunthaler, René; Rosengarten, Renate; Chopra-Dewasthaly, Rohini

2014-11-01

Generally regarded as extracellular pathogens, molecular mechanisms of mycoplasma persistence, chronicity and disease spread are largely unknown. Mycoplasma agalactiae, an economically important pathogen of small ruminants, causes chronic infections that are difficult to eradicate. Animals continue to shed the agent for several months and even years after the initial infection, in spite of long antibiotic treatment. However, little is known about the strategies that M. agalactiae employs to survive and spread within an immunocompetent host to cause chronic disease. Here, we demonstrate for the first time its ability to invade cultured human (HeLa) and ruminant (BEND and BLF) host cells. Presence of intracellular mycoplasmas is clearly substantiated using differential immunofluorescence technique and quantitative gentamicin invasion assays. Internalized M. agalactiae could survive and exit the cells in a viable state to repopulate the extracellular environment after complete removal of extracellular bacteria with gentamicin. Furthermore, an experimental sheep intramammary infection was carried out to evaluate its systemic spread to organs and host niches distant from the site of initial infection. Positive results obtained via PCR, culture and immunohistochemistry, especially the latter depicting the presence of M. agalactiae in the cytoplasm of mammary duct epithelium and macrophages, clearly provide the first formal proof of M. agalactiae's capability to translocate across the mammary epithelium and systemically disseminate to distant inner organs. Altogether, the findings of these in vitro and in vivo studies indicate that M. agalactiae is capable of entering host cells and this might be the strategy that it employs at a population level to ward off the host immune response and antibiotic action, and to disseminate to new and safer niches to later egress and once again proliferate upon the return of favorable conditions to cause persistent chronic infections. Copyright © 2014 The Authors. Published by Elsevier GmbH.. All rights reserved.

Yeast Infection (Vaginal)

MedlinePlus

Yeast infection (vaginal) Overview A vaginal yeast infection is a fungal infection that causes irritation, discharge and intense itchiness ... symptoms Causes The fungus candida causes a vaginal yeast infection. Your vagina naturally contains a balanced mix of yeast, including ...

Recurrent catheter-related infection caused by a single clone of Mycobacterium chelonae with two colonial morphotypes.

PubMed

Hsueh, P R; Teng, L J; Yang, P C; Chen, Y C; Ho, S W; Luh, K T

1998-05-01

We describe herein a recurrent catheter-related (Port-A-Cath; Smiths Industries Medical Systems [SIMS] Deltec, Inc., St. Paul, Minn.) infection caused by multidrug-resistant Mycobacterium chelonae with two colonial morphotypes in a 53-year-old woman with gastric adenocarcinoma. Four isolates recovered from this patient within a 3-month period were found to belong to a single clone on the basis of the isolates' identical antibiotypes as determined by the E test and their identical random amplified polymorphic DNA patterns.

Scytalidium dimidiatum and Lecythophora hoffmannii: unusual causes of fungal infections in a patient with AIDS.

PubMed Central

Marriott, D J; Wong, K H; Aznar, E; Harkness, J L; Cooper, D A; Muir, D

1997-01-01

Immunocompromised patients are susceptible to infections by fungi that seldom cause disease in humans. We describe a human immunodeficiency virus-infected patient who had simultaneous infections with two fungi which are rare causes of serious infection: Lecythophora hoffmannii, causing chronic sinusitis, and Scytalidium dimidiatum, causing skin lesions, lymphangitis, and lymphadenitis. The clinical and pathologic findings are discussed. PMID:9350765

Associations and Trends in Cause-Specific Rates of Death Among Persons Reported with HIV Infection, 23 U.S. Jurisdictions, Through 2011

PubMed Central

Adih, William K.; Selik, Richard M.; Hall, H. Irene; Babu, Aruna Surendera; Song, Ruiguang

2016-01-01

Background: Published death rates for persons with HIV have not distinguished deaths due to HIV from deaths due to other causes. Cause-specific death rates would allow better assessment of care needs. Methods: Using data reported to the US national HIV surveillance system, we examined a) associations between selected decedent characteristics and causes of death during 2007-2011, b) trends in rates of death due to underlying causes among persons with AIDS during 1990-2011, and among all persons with diagnosed HIV infection (with or without AIDS) during 2000-2011. Results: During 2007-2011, non-HIV-attributable causes of death with the highest rates per 1,000 person-years were heart disease (2.0), non-AIDS cancers other than lung cancer (1.4), and accidents (0.8). During 1990-2011, among persons with AIDS, the annual rate of death due to HIV-attributable causes decreased by 89% (from 122.0 to 13.2), and the rate due to non-HIV-attributable-causes decreased by 57% (from 20.0 to 8.6), while the percentage of deaths caused by non-HIV-attributable causes increased from 11% to 43%. During 2000-2011, among persons with HIV infection, the rate of death due to HIV-attributable causes decreased by 69% (from 26.4 to 8.3), and the rate due to non-HIV-attributable causes decreased by 28% (from 10.5 to 7.6), while the percentage of deaths caused by non-HIV-attributable causes increased from 25% to 48%. Conclusion: Among HIV-infected persons, as rates of death due to HIV-attributable causes decreased, rates due to non-HIV-attributable causes also decreased, but the percentages of deaths due to non-HIV-attributable causes, such as heart disease and non-AIDS cancers increased. PMID:27708746

Nocardia farcinica brain abscess: epidemiology, pathophysiology, and literature review.

PubMed

Kumar, V Anil; Augustine, Deepthi; Panikar, Dilip; Nandakumar, Aswathy; Dinesh, Kavitha R; Karim, Shamsul; Philip, Rosamma

2014-10-01

Infections caused by Nocardia farcinica are potentially lethal because of the organism's tendency to disseminate and resist antibiotics. Central nervous system involvement has been documented in 30% of infections caused N. farcinica. Case report and review of the literature. A case of primary brain abscess caused by N. farcinica, identified by 16SrRNA sequencing, is presented, and 39 cases reported previously in the literature are reviewed. Our patient underwent a neuronavigation-guided right frontal craniotomy and was treated with trimethoprim/sulfamethoxazole and amoxicillin-clavulanic acid for 12 mo. He showed marginal improvement in his prior left hemiparesis at the last review 14 months later. Cases of N. farcinica infections are being reported increasingly because of recent changes in taxonomy and diagnostic methodology. This change in epidemiology has implications for therapy because of the organism's pathogenicity and natural resistance to multiple antimicrobial agents, including third-generation cephalosporins. Any delay in starting appropriate antibiotic therapy can have adverse consequences.

Premature delivery due to intrauterine Candida infection that caused neonatal congenital cutaneous candidiasis: a case report.

PubMed

Ito, Fumitake; Okubo, Tomoharu; Yasuo, Tadahiro; Mori, Taisuke; Iwasa, Koichi; Iwasaku, Kazuhiro; Kitawaki, Jo

2013-01-01

Congenital cutaneous candidiasis is a very rare disease with less than 100 cases published in the medical literature. Neonates having this disease present with systemic skin lesions caused by intrauterine Candida infections. We present a case of threatened premature delivery due to Candida chorioamnionitis, which caused both maternal postpartum endometritis and neonatal congenital cutaneous candidiasis. A 34-year-old woman who was admitted for fetal membrane bulging at 20 weeks of gestation underwent McDonald cervical cerclage. We diagnosed threatened premature delivery due to intrauterine infection; therefore, we terminated the gestation by cesarean section at 24 weeks of gestation. Fungi-like yeast was detected in infantile gastric juice. Histopathological findings of the placenta revealed that Candida albicans mycelium invaded the placenta, chorioamniotic membrane and umbilical cord. © 2012 The Authors. Journal of Obstetrics and Gynaecology Research © 2012 Japan Society of Obstetrics and Gynecology.

Oral infections and orofacial pain in Alzheimer’s disease: Case report and review

PubMed Central

de Siqueira, Silvia Regina Dowgan T.; Rolim, Thaís de Souza; Teixeira, Manoel Jacobsen; Nitrini, Ricardo; Anghinah, Renato; de Siqueira, José Tadeu T.

2010-01-01

Dental infections, frequent in the general population, are a common cause of inflammation with systemic impact, and are the most common cause of orofacial pain. Temporomandibular disorders are also frequent in the elderly and represent an important cause of secondary headache. Both inflammation and pain can also contribute to cognitive, functional and behavioral impairment of the elderly and aggravate symptoms of patients with Alzheimer’s disease (AD). We report a case of a 74-year-old woman with AD and chronic facial pain who had a significant improvement in functional activities as well as in cognition and depressive symptoms after successful treatment of her facial pain. Patients with AD have higher compromise of oral health with infections and teeth loss. The investigation of orofacial pain should be performed in patients with AD, because of the associations reviewed and given the potential for improvement as highlighted by this case. PMID:29213678

[A case of fascioliasis in the intrahepatic duct with concurrent clonochiasis].

PubMed

Kim, Seung-Hyun; Jung, Chang-Kil; Her, Jin; Hur, Ki-Hwan; Choi, Jae-Hyuc; Kang, Kee-Hoon; Hwang, Chan-Hee

2014-11-01

The main causes of biliary obstruction are stones and cancers. Fascioliasis is a very rare case which causes biliary obstruction. Fascioliasis is a zoonosis caused by Fasciola hepatica which infects herbivores like sheep and cattle. F. hepatica lives in the biliary system or the liver parenchyma of a host. In Korea, the occurrence of this infection in human is very rare and only few cases have been reported. A 32-year-old male presented with upper abdominal pain and jaundice. His laboratory finding revealed elevated liver transaminases. Abdomen CT scan showed mild left intrahepatic bile duct dilatation. On ERCP, adult F. hepatica worms were found and were thus removed. Concurrently, clonorchiasis was diagnosed by stool exam and serologic enzyme-linked immunosorbent assay test. Clonorchiasis was treated with praziquantel. Herein, we report a case of intrahepatic bile duct dilatation due to F. hepatica infection with concurrent Clonorchis sinensis infestation.

Destructive disinfection of infected brood prevents systemic disease spread in ant colonies.

PubMed

Pull, Christopher D; Ugelvig, Line V; Wiesenhofer, Florian; Grasse, Anna V; Tragust, Simon; Schmitt, Thomas; Brown, Mark Jf; Cremer, Sylvia

2018-01-09

In social groups, infections have the potential to spread rapidly and cause disease outbreaks. Here, we show that in a social insect, the ant Lasius neglectus , the negative consequences of fungal infections ( Metarhizium brunneum ) can be mitigated by employing an efficient multicomponent behaviour, termed destructive disinfection, which prevents further spread of the disease through the colony. Ants specifically target infected pupae during the pathogen's non-contagious incubation period, utilising chemical 'sickness cues' emitted by pupae. They then remove the pupal cocoon, perforate its cuticle and administer antimicrobial poison, which enters the body and prevents pathogen replication from the inside out. Like the immune system of a metazoan body that specifically targets and eliminates infected cells, ants destroy infected brood to stop the pathogen completing its lifecycle, thus protecting the rest of the colony. Hence, in an analogous fashion, the same principles of disease defence apply at different levels of biological organisation.

Vaccine-preventable infections in Systemic Lupus Erythematosus

PubMed Central

Murdaca, Giuseppe; Orsi, Andrea; Spanò, Francesca; Faccio, Valeria; Puppo, Francesco; Durando, Paolo; Icardi, Giancarlo; Ansaldi, Filippo

2016-01-01

Systemic Lupus Erythematosus (SLE) is characterized by abnormal autoantibody production and clearance. Infections are among the most important causes of morbidity and mortality in SLE patients; they have an increased frequency of severe bacterial and viral infections possibly due to inherited genetic and immunologic defects and to immunosuppressive therapies. In addition, infectious agents can switch on lupus disease expression and activity. Among the strategies to reduce the risk of infection, vaccination can be considered the most reliable option. Most vaccines are effective and safe in SLE patients, although in certain cases immunogenicity may be sub-optimal and vaccination can trigger a flare. Although these issues are currently unresolved, the risk benefit balance is in favor for vaccination to reduce the risk of infection in SLE patients. In the present review we discuss the preventive strategies currently recommended to reduce bacterial and viral infections in SLE. PMID:26750996

Infections After Orthotopic Liver Transplantation

PubMed Central

Pedersen, Mark; Seetharam, Anil

2014-01-01

Opportunistic infections are a leading cause of morbidity and mortality after orthotopic liver transplantation. Systemic immunosuppression renders the liver recipient susceptible to de novo infection with bacteria, viruses and fungi post-transplantation as well to reactivation of pre-existing, latent disease. Pathogens are also transmissible via the donor organ. The time from transplantation and degree of immunosuppression may guide the differential diagnosis of potential infectious agents. However, typical systemic signs and symptoms of infection are often absent or blunted after transplant and a high index of suspicion is needed. Invasive procedures are often required to procure tissue for culture and guide antimicrobial therapy. Antimicrobial prophylaxis reduces the incidence of opportunistic infections and is routinely employed in the care of patients after liver transplant. In this review, we survey common bacterial, fungal, and viral infections after orthotopic liver transplantation and highlight recent developments in their diagnosis and management. PMID:25755581

Destructive disinfection of infected brood prevents systemic disease spread in ant colonies

PubMed Central

Ugelvig, Line V; Wiesenhofer, Florian; Grasse, Anna V; Tragust, Simon; Schmitt, Thomas; Brown, Mark JF

2018-01-01

In social groups, infections have the potential to spread rapidly and cause disease outbreaks. Here, we show that in a social insect, the ant Lasius neglectus, the negative consequences of fungal infections (Metarhizium brunneum) can be mitigated by employing an efficient multicomponent behaviour, termed destructive disinfection, which prevents further spread of the disease through the colony. Ants specifically target infected pupae during the pathogen’s non-contagious incubation period, utilising chemical ‘sickness cues’ emitted by pupae. They then remove the pupal cocoon, perforate its cuticle and administer antimicrobial poison, which enters the body and prevents pathogen replication from the inside out. Like the immune system of a metazoan body that specifically targets and eliminates infected cells, ants destroy infected brood to stop the pathogen completing its lifecycle, thus protecting the rest of the colony. Hence, in an analogous fashion, the same principles of disease defence apply at different levels of biological organisation. PMID:29310753

Outbreak of Bacillus cereus infections in a neonatal intensive care unit traced to balloons used in manual ventilation.

PubMed

Van Der Zwet, W C; Parlevliet, G A; Savelkoul, P H; Stoof, J; Kaiser, A M; Van Furth, A M; Vandenbroucke-Grauls, C M

2000-11-01

In 1998, an outbreak of systemic infections caused by Bacillus cereus occurred in the Neonatal Intensive Care Unit of the University Hospital Vrije Universiteit, Amsterdam, The Netherlands. Three neonates developed sepsis with positive blood cultures. One neonate died, and the other two neonates recovered. An environmental survey, a prospective surveillance study of neonates, and a case control study were performed, in combination with molecular typing, in order to identify potential sources and transmission routes of infection. Genotypic fingerprinting by amplified-fragment length polymorphism (AFLP) showed that the three infections were caused by a single clonal type of B. cereus. The same strain was found in trachea aspirate specimens of 35 other neonates. The case control study showed mechanical ventilation with a Sensormedics ventilation machine to be a risk factor for colonization and/or infection (odds ratio, 9.8; 95% confidence interval, 1.1 to 88.2). Prospective surveillance showed that colonization with B. cereus occurred exclusively in the respiratory tract of mechanically ventilated neonates. The epidemic strain of B. cereus was found on the hands of nursing staff and in balloons used for manual ventilation. Sterilization of these balloons ended the outbreak. We conclude that B. cereus can cause outbreaks of severe opportunistic infection in neonates. Typing by AFLP proved very useful in the identification of the outbreak and in the analysis of strains recovered from the environment to trace the cause of the epidemic.

Outbreak of Bacillus cereus Infections in a Neonatal Intensive Care Unit Traced to Balloons Used in Manual Ventilation

PubMed Central

Van Der Zwet, Wil C.; Parlevliet, Gerard A.; Savelkoul, Paul H.; Stoof, Jeroen; Kaiser, Annie M.; Van Furth, A. Marceline; Vandenbroucke-Grauls, Christina M.

2000-01-01

In 1998, an outbreak of systemic infections caused by Bacillus cereus occurred in the Neonatal Intensive Care Unit of the University Hospital Vrije Universiteit, Amsterdam, The Netherlands. Three neonates developed sepsis with positive blood cultures. One neonate died, and the other two neonates recovered. An environmental survey, a prospective surveillance study of neonates, and a case control study were performed, in combination with molecular typing, in order to identify potential sources and transmission routes of infection. Genotypic fingerprinting by amplified-fragment length polymorphism (AFLP) showed that the three infections were caused by a single clonal type of B. cereus. The same strain was found in trachea aspirate specimens of 35 other neonates. The case control study showed mechanical ventilation with a Sensormedics ventilation machine to be a risk factor for colonization and/or infection (odds ratio, 9.8; 95% confidence interval, 1.1 to 88.2). Prospective surveillance showed that colonization with B. cereus occurred exclusively in the respiratory tract of mechanically ventilated neonates. The epidemic strain of B. cereus was found on the hands of nursing staff and in balloons used for manual ventilation. Sterilization of these balloons ended the outbreak. We conclude that B. cereus can cause outbreaks of severe opportunistic infection in neonates. Typing by AFLP proved very useful in the identification of the outbreak and in the analysis of strains recovered from the environment to trace the cause of the epidemic. PMID:11060080

10 × '20 Progress—Development of New Drugs Active Against Gram-Negative Bacilli: An Update From the Infectious Diseases Society of America

PubMed Central

Boucher, Helen W.; Talbot, George H.; Benjamin, Daniel K.; Bradley, John; Guidos, Robert J.; Jones, Ronald N.; Murray, Barbara E.; Bonomo, Robert A.; Gilbert, David

2013-01-01

Infections caused by antibiotic-resistant bacteria, especially the “ESKAPE” pathogens, continue to increase in frequency and cause significant morbidity and mortality. New antimicrobial agents are greatly needed to treat infections caused by gram-negative bacilli (GNB) resistant to currently available agents. The Infectious Diseases Society of America (IDSA) continues to propose legislative, regulatory, and funding solutions to this continuing crisis. The current report updates the status of development and approval of systemic antibiotics in the United States as of early 2013. Only 2 new antibiotics have been approved since IDSA's 2009 pipeline status report, and the number of new antibiotics annually approved for marketing in the United States continues to decline. We identified 7 drugs in clinical development for treatment of infections caused by resistant GNB. None of these agents was included in our 2009 list of antibacterial compounds in phase 2 or later development, but unfortunately none addresses the entire spectrum of clinically relevant GNB resistance. Our survey demonstrates some progress in development of new antibacterial drugs that target infections caused by resistant GNB, but progress remains alarmingly elusive. IDSA stresses our conviction that the antibiotic pipeline problem can be solved by the collaboration of global leaders to develop creative incentives that will stimulate new antibacterial research and development. Our aim is the creation of a sustainable global antibacterial drug research and development enterprise with the power in the short term to develop 10 new, safe, and efficacious systemically administered antibiotics by 2020 as called for in IDSA's “10 × '20 Initiative.” PMID:23599308

Proteflazid® and local immunity in diseases caused by human papillomavirus, herpesvirus and mixed urogenital infections.

PubMed

Kaminsky, Vjacheslav; Chernyshov, Viktor; Grynevych, Oleksandr; Benyuk, Vasil; Kornatskaya, Alla; Shalko, Miroslava; Usevich, Igor; Revenko, Oleg; Shepetko, Maxim; Solomakha, Ludmila

2017-03-21

Reporting of clinical trials results for Proteflazid® in the drug formulation suppositories and vaginal swabs soaked in the solution of the drug to the local immunity of the female reproductive tract. The aim of study was to examine the state of local immunity in the reproductive tract of women with sexually transmitted diseases caused by human papillomavirus, herpes viruses (Type 1, 2) and mixed infection (herpes viruses + chlamydia). The trials involved 216 women with viral sexually transmitted diseases: Cervical Dysplasia associated with papillomavirus infection (HPV) (Group 1); Herpes genitalis type 1 (HSV- 1) and type 2 (HSV-1) (Group 2); mixed infection - HSV-1, HSV-2 and chlamydia (Group 3). Treatment results have confirmed that Proteflazid® contributes to sustainable performance improvement of basic factors of local immunity - sIgA, lysozyme and complement component C3 in the cervical mucus for all three groups of women. Proteflazid® enhances level of local immunity markers (sIgA, lysozyme, C3 complement component) and improves their ratios. Also it intensifies anticontagious activity of mucosal protection and female reproductive system as whole, during treatment diseases caused by human papillomavirus, herpesvirus and mixed urogenital infections (herpesvirus and chlamydia).

Neuroimaging findings of congenital Zika virus infection: a pictorial essay.

PubMed

Zare Mehrjardi, Mohammad; Poretti, Andrea; Huisman, Thierry A G M; Werner, Heron; Keshavarz, Elham; Araujo Júnior, Edward

2017-03-01

Zika virus (ZIKV) is a mosquito-borne arbovirus from the Flaviviridae family. It had caused several epidemics since its discovery in 1947, but there was no significant attention to this virus until the recent outbreak in Brazil in 2015. The main concern is the causal relationship between prenatal ZIKV infection and congenital microcephaly, which has been confirmed recently. Moreover, ZIKV may cause other central nervous system abnormalities such as brain parenchymal atrophy with secondary ventriculomegaly, intracranial calcification, malformations of cortical development (such as polymicrogyria, and lissencephaly-pachygyria), agenesis/hypoplasia of the corpus callosum, cerebellar and brainstem hypoplasia, sensorineural hearing-loss, and ocular abnormalities as well as arthrogryposis in the infected fetuses. Postnatal (acquired) ZIKV infection usually has an asymptomatic or mildly symptomatic course, while prenatal (congenital) ZIKV infection has a more severe course and may cause severe brain anomalies that are described as congenital Zika syndrome. In this pictorial essay, we aim to illustrate the prenatal and postnatal neuroimaging findings that may be seen in fetuses and neonates with congenital Zika syndrome, and will discuss possible radiological differential diagnoses. A detailed knowledge of these findings is paramount for an early correct diagnosis, prognosis determination, and counseling of the affected children and families.

Multiplicity of Mathematical Modeling Strategies to Search for Molecular and Cellular Insights into Bacteria Lung Infection

PubMed Central

Cantone, Martina; Santos, Guido; Wentker, Pia; Lai, Xin; Vera, Julio

2017-01-01

Even today two bacterial lung infections, namely pneumonia and tuberculosis, are among the 10 most frequent causes of death worldwide. These infections still lack effective treatments in many developing countries and in immunocompromised populations like infants, elderly people and transplanted patients. The interaction between bacteria and the host is a complex system of interlinked intercellular and the intracellular processes, enriched in regulatory structures like positive and negative feedback loops. Severe pathological condition can emerge when the immune system of the host fails to neutralize the infection. This failure can result in systemic spreading of pathogens or overwhelming immune response followed by a systemic inflammatory response. Mathematical modeling is a promising tool to dissect the complexity underlying pathogenesis of bacterial lung infection at the molecular, cellular and tissue levels, and also at the interfaces among levels. In this article, we introduce mathematical and computational modeling frameworks that can be used for investigating molecular and cellular mechanisms underlying bacterial lung infection. Then, we compile and discuss published results on the modeling of regulatory pathways and cell populations relevant for lung infection and inflammation. Finally, we discuss how to make use of this multiplicity of modeling approaches to open new avenues in the search of the molecular and cellular mechanisms underlying bacterial infection in the lung. PMID:28912729

Multiplicity of Mathematical Modeling Strategies to Search for Molecular and Cellular Insights into Bacteria Lung Infection.

PubMed

Cantone, Martina; Santos, Guido; Wentker, Pia; Lai, Xin; Vera, Julio

2017-01-01

Even today two bacterial lung infections, namely pneumonia and tuberculosis, are among the 10 most frequent causes of death worldwide. These infections still lack effective treatments in many developing countries and in immunocompromised populations like infants, elderly people and transplanted patients. The interaction between bacteria and the host is a complex system of interlinked intercellular and the intracellular processes, enriched in regulatory structures like positive and negative feedback loops. Severe pathological condition can emerge when the immune system of the host fails to neutralize the infection. This failure can result in systemic spreading of pathogens or overwhelming immune response followed by a systemic inflammatory response. Mathematical modeling is a promising tool to dissect the complexity underlying pathogenesis of bacterial lung infection at the molecular, cellular and tissue levels, and also at the interfaces among levels. In this article, we introduce mathematical and computational modeling frameworks that can be used for investigating molecular and cellular mechanisms underlying bacterial lung infection. Then, we compile and discuss published results on the modeling of regulatory pathways and cell populations relevant for lung infection and inflammation. Finally, we discuss how to make use of this multiplicity of modeling approaches to open new avenues in the search of the molecular and cellular mechanisms underlying bacterial infection in the lung.

Rapid and amplification-free detection of fish pathogens by utilizing a molecular beacon-based microfluidic system.

PubMed

Su, Yi-Chih; Wang, Chih-Hung; Chang, Wen-Hsin; Chen, Tzong-Yueh; Lee, Gwo-Bin

2015-01-15

Nervous necrosis virus (NNV) and iridovirus are highly infectious pathogens that can cause lethal diseases in various species of fish. These infectious diseases have no effective treatments and the mortality rate is over 80%, which could cause dramatic economic losses in the aquaculture industry. Conventional diagnostic methods of NNV or iridovirus infected fishes, such as virus culture, enzyme-linked immunosorbent assays and nucleic acid assays usually require time-consuming and complex procedures performed by specialized technicians with delicate laboratory facilities. Rapid, simple, accurate and on-site detection of NNV and iridovirus infections would enable timely preventive measures such as immediate sacrifice of infected fishes, and is therefore critically needed for the aquaculture industry. In this study, a microfluidic-based assay that employ magnetic beads conjugated with viral deoxyribonucleic acid (DNA) capturing probes and fluorescent DNA molecular beacons were developed to rapidly detect NNV and iridovirus. Importantly, this new assay was realized in an integrated microfluidic system with a custom-made control system. With this approach, direct and automated NNV and iridovirus detection from infected fishes can be achieved in less than 30 min. Therefore, this molecular-beacon based microfluidic system presents a potentially promising tool for rapid diagnosis of fish pathogens in the field in the future. Copyright © 2014 Elsevier B.V. All rights reserved.

New insights into gastrointestinal anthrax infection.

PubMed

Owen, Jennifer L; Yang, Tao; Mohamadzadeh, Mansour

2015-03-01

Bacterial infections are the primary cause of gastrointestinal (GI) disorders in both developing and developed countries, and are particularly dangerous for infants and children. Bacillus anthracis is the 'archetype zoonotic' pathogen; no other infectious disease affects such a broad range of species, including humans. Importantly, there are more case reports of GI anthrax infection in children than inhalational disease. Early diagnosis is difficult and widespread systemic disease develops rapidly. This review highlights new findings concerning the roles of the gut epithelia, commensal microbiota, and innate lymphoid cells (ILCs) in initiation of disease and systemic dissemination in animal models of GI anthrax, the understanding of which is crucial to designing alternative therapies that target the establishment of infection. Copyright © 2014 Elsevier Ltd. All rights reserved.

Hemorrhagic Transformation of Scrub Typhus Encephalitis: A Rare Entity.

PubMed

Kim, H-C; Yoon, K-W; Yoo, D-S; Cho, C-S

2015-12-01

Central nervous system (CNS) involvement of scrub typhus infection is well known. Most CNS involvement of scrub typhus infection present as meningitis or encephalitis. We report on a patient suffering from hemorrhagic transformation of intracranial lesions caused by Orientia tsutsugamushi. A 53-year-old female farmer who was infected by scrub typhus was treated with doxycycline and recovered from the systemic illness. However, headache persisted. Brain radiologic studies revealed acute intracranial hemorrhage and enhancing lesion, which implied a CNS involvement. Hemorrhagic transformation of encephalitis by scrub typhus is very rare complication and to our best knowledge, this is the first report of hemorrhagic transformation of scrub typhus encephalitis. Clinician should consider the possibility of hemorrhagic transformation of encephalitis in cases of scrub typhus infection.

Myenteric plexus is differentially affected by infection with distinct Trypanosoma cruzi strains in Beagle dogs.

PubMed

Nogueira-Paiva, Nívia Carolina; Fonseca, Kátia da Silva; Vieira, Paula Melo de Abreu; Diniz, Lívia Figueiredo; Caldas, Ivo Santana; Moura, Sandra Aparecida Lima de; Veloso, Vanja Maria; Guedes, Paulo Marcos da Matta; Tafuri, Washington Luiz; Bahia, Maria Terezinha; Carneiro, Cláudia Martins

2014-02-01

Chagasic megaoesophagus and megacolon are characterised by motor abnormalities related to enteric nervous system lesions and their development seems to be related to geographic distribution of distinct Trypanosoma cruzi subpopulations. Beagle dogs were infected with Y or Berenice-78 (Be-78) T. cruzi strains and necropsied during the acute or chronic phase of experimental disease for post mortem histopathological evaluation of the oesophagus and colon. Both strains infected the oesophagus and colon and caused an inflammatory response during the acute phase. In the chronic phase, inflammatory process was observed exclusively in the Be-78 infected animals, possibly due to a parasitism persistent only in this group. Myenteric denervation occurred during the acute phase of infection for both strains, but persisted chronically only in Be-78 infected animals. Glial cell involvement occurred earlier in animals infected with the Y strain, while animals infected with the Be-78 strain showed reduced glial fibrillary acidic protein immunoreactive area of enteric glial cells in the chronic phase. These results suggest that although both strains cause lesions in the digestive tract, the Y strain is associated with early control of the lesion, while the Be-78 strain results in progressive gut lesions in this model.

Clostridium difficile infection

PubMed Central

Smits, Wiep Klaas; Lyras, Dena; Lacy, D. Borden; Wilcox, Mark H.; Kuijper, Ed J.

2017-01-01

Infection of the colon with the Gram-positive bacterium Clostridium difficile is potentially life threatening, especially in elderly people and in patients who have dysbiosis of the gut microbiota following antimicrobial drug exposure. C. difficile is the leading cause of health-care-associated infective diarrhoea. The life cycle of C. difficile is influenced by antimicrobial agents, the host immune system, and the host microbiota and its associated metabolites. The primary mediators of inflammation in C. difficile infection (CDI) are large clostridial toxins, toxin A (TcdA) and toxin B (TcdB), and, in some bacterial strains, the binary toxin CDT. The toxins trigger a complex cascade of host cellular responses to cause diarrhoea, inflammation and tissue necrosis — the major symptoms of CDI. The factors responsible for the epidemic of some C. difficile strains are poorly understood. Recurrent infections are common and can be debilitating. Toxin detection for diagnosis is important for accurate epidemiological study, and for optimal management and prevention strategies. Infections are commonly treated with specific antimicrobial agents, but faecal microbiota transplants have shown promise for recurrent infections. Future biotherapies for C. difficile infections are likely to involve defined combinations of key gut microbiota. PMID:27158839

Measles virus, immune control and persistence

PubMed Central

Griffin, Diane E.; Lin, Wen-Hsuan; Pan, Chien-Hsiung

2012-01-01

Measles remains one of the most important causes of child morbidity and mortality worldwide with the greatest burden in the youngest children. Most acute measles deaths are due to secondary infections that result from a poorly understood measles-induced suppression of immune responses. Young children are also vulnerable to late development of subacute sclerosing panencephalitis, a progressive, uniformly fatal neurologic disease caused by persistent measles virus (MeV) infection. During acute infection, the rash marks the appearance of the adaptive immune response and CD8+ T cell-mediated clearance of infectious virus. However, after clearance of infectious virus, MeV RNA persists and can be detected in blood, respiratory secretions, urine and lymphoid tissue for many weeks to months. This prolonged period of virus clearance may help to explain measles immunosuppression and the development of lifelong immunity to re-infection, as well as occasional infection of the nervous system. Once MeV infects neurons, the virus can spread transynaptically and the envelope proteins needed to form infectious virus are unnecessary, accumulate mutations and can establish persistent infection. Identification of the immune mechanisms required for clearance of MeV RNA from multiple sites will enlighten our understanding of the development of disease due to persistent infection. PMID:22316382

Comparison of Rates of Death Having any Death-Certificate Mention of Heart, Kidney, or Liver Disease Among Persons Diagnosed with HIV Infection with those in the General US Population, 2009-2011.

PubMed

Whiteside, Y Omar; Selik, Richard; An, Qian; Huang, Taoying; Karch, Debra; Hernandez, Angela L; Hall, H Irene

2015-01-01

Compare age-adjusted rates of death due to liver, kidney, and heart diseases during 2009-2011 among US residents diagnosed with HIV infection with those in the general population. Numerators were numbers of records of multiple-cause mortality data from the national vital statistics system with an ICD-10 code for the disease of interest (any mention, not necessarily the underlying cause), divided into those 1) with and 2) without an additional code for HIV infection. Denominators were 1) estimates of persons living with diagnosed HIV infection from national HIV surveillance system data and 2) general population estimates from the US Census Bureau. We compared age-adjusted rates overall (unstratified by sex, race/ethnicity, or region of residence) and stratified by demographic group. Overall, compared with the general population, persons diagnosed with HIV infection had higher age-adjusted rates of death reported with hepatitis B (rate ratio [RR]=42.6; 95% CI: 34.7-50.7), hepatitis C (RR=19.4; 95% CI: 18.1-20.8), liver disease excluding hepatitis B or C (RR=2.1; 95% CI: 1.8-2.3), kidney disease (RR=2.4; 95% CI: 2.2-2.6), and cardiomyopathy (RR=1.9; 95% CI: 1.6-2.3), but lower rates of death reported with ischemic heart disease (RR=0.6; 95% CI: 0.6-0.7) and heart failure (RR=0.8; 95% CI: 0.6-0.9). However, the differences in rates of death reported with the heart diseases were insignificant in some demographic groups. Persons with HIV infection have a higher risk of death with liver and kidney diseases reported as causes than the general population.

Giardia Alters Commensal Microbial Diversity throughout the Murine Gut

PubMed Central

Barash, N. R.; Maloney, J. G.

2017-01-01

ABSTRACT Giardia lamblia is the most frequently identified protozoan cause of intestinal infection. Over 200 million people are estimated to have acute or chronic giardiasis, with infection rates approaching 90% in areas where Giardia is endemic. Despite its significance in global health, the mechanisms of pathogenesis associated with giardiasis remain unclear, as the parasite neither produces a known toxin nor induces a robust inflammatory response. Giardia colonization and proliferation in the small intestine of the host may, however, disrupt the ecological homeostasis of gastrointestinal commensal microbes and contribute to diarrheal disease associated with giardiasis. To evaluate the impact of Giardia infection on the host microbiota, we used culture-independent methods to quantify shifts in the diversity of commensal microbes throughout the gastrointestinal tract in mice infected with Giardia. We discovered that Giardia's colonization of the small intestine causes a systemic dysbiosis of aerobic and anaerobic commensal bacteria. Specifically, Giardia colonization is typified by both expansions in aerobic Proteobacteria and decreases in anaerobic Firmicutes and Melainabacteria in the murine foregut and hindgut. Based on these shifts, we created a quantitative index of murine Giardia-induced microbial dysbiosis. This index increased at all gut regions during the duration of infection, including both the proximal small intestine and the colon. Giardiasis could be an ecological disease, and the observed dysbiosis may be mediated directly via the parasite's unique anaerobic fermentative metabolism or indirectly via parasite induction of gut inflammation. This systemic alteration of murine gut commensal diversity may be the cause or the consequence of inflammatory and metabolic changes throughout the gut. Shifts in the commensal microbiota may explain observed variations in giardiasis between hosts with respect to host pathology, degree of parasite colonization, infection initiation, and eventual clearance. PMID:28396324

The implant infection paradox: why do some succeed when others fail? Opinion and discussion paper.

PubMed

Yue, C; Zhao, B; Ren, Y; Kuijer, R; van der Mei, H C; Busscher, H J; Rochford, E T J

2015-06-05

Biomaterial-implants are frequently used to restore function and form of human anatomy. However, the presence of implanted biomaterials dramatically elevates infection risk. Paradoxically, dental-implants placed in a bacteria-laden milieu experience moderate failure-rates, due to infection (0.0-1.1%), similar to the ones of joint-arthroplasties placed in a near-sterile environment (0.1-1.3%). Transcutaneous bone-fixation pins breach the immune-barrier of the epidermis, exposing underlying sterile-tissue to an unsterile external environment. In contrast to dental-implants, also placed in a highly unsterile environment, these pins give rise to relatively high infection-associated failure-rates of up to 23.0%. Herein, we attempt to identify causes as to why dental-implants so often succeed, where others fail. The major part of all implants considered are metal-made, with similar surface-finishes. Material choice was therefore discarded as underlying the paradox. Antimicrobial activity of saliva has also been suggested as a cause for the success of dental-implants, but was discarded because saliva is the implant-site-fluid from which viable bacteria adhere. Crevicular fluid was discarded as it is largely analogous to serum. Instead, we attribute the relative success of dental-implants to (1) ability of oral tissues to heal rapidly in the continuous presence of commensal bacteria and opportunistic pathogens, and (2) tolerance of the oral immune-system. Inability of local tissue to adhere, spread and grow in presence of bacteria and an intolerant immune-system are identified as the likely main causes explaining the susceptibility of other implants to infection-associated failure. In conclusion, it is the authors' belief that new anti-infection strategies for a wide range of biomaterial-implants may be derived from the relative success of dental-implants.

Clinical findings for fungal infections caused by methylprednisolone injections.

PubMed

Chiller, Tom M; Roy, Monika; Nguyen, Duc; Guh, Alice; Malani, Anurag N; Latham, Robert; Peglow, Sheree; Kerkering, Tom; Kaufman, David; McFadden, Jevon; Collins, Jim; Kainer, Marion; Duwve, Joan; Trump, David; Blackmore, Carina; Tan, Christina; Cleveland, Angela A; MacCannell, Tara; Muehlenbachs, Atis; Zaki, Sherif R; Brandt, Mary E; Jernigan, John A

2013-10-24

Since September 18, 2012, public health officials have been investigating a large outbreak of fungal meningitis and other infections in patients who received epidural, paraspinal, or joint injections with contaminated lots of methylprednisolone acetate. Little is known about infections caused by Exserohilum rostratum, the predominant outbreak-associated pathogen. We describe the early clinical course of outbreak-associated infections. We reviewed medical records for outbreak cases reported to the Centers for Disease Control and Prevention before November 19, 2012, from the six states with the most reported cases (Florida, Indiana, Michigan, New Jersey, Tennessee, and Virginia). Polymerase-chain-reaction assays and immunohistochemical testing were performed on clinical isolates and tissue specimens for pathogen identification. Of 328 patients without peripheral-joint infection who were included in this investigation, 265 (81%) had central nervous system (CNS) infection and 63 (19%) had non-CNS infections only. Laboratory evidence of E. rostratum was found in 96 of 268 patients (36%) for whom samples were available. Among patients with CNS infections, strokes were associated with an increased severity of abnormalities in cerebrospinal fluid (P<0.001). Non-CNS infections were more frequent later in the course of the outbreak (median interval from last injection to diagnosis, 39 days for epidural abscess and 21 days for stroke; P<0.001), and such infections developed in patients with and in those without meningitis. The initial clinical findings from this outbreak suggest that fungal infections caused by epidural and paraspinal injection of a contaminated glucocorticoid product can result in a broad spectrum of clinical disease, reflecting possible variations in the pathogenic mechanism and in host and exposure risk factors. (Funded by the Centers for Disease Control and Prevention.).

Adenovirus vector infection of non-small-cell lung cancer cells is a trigger for multi-drug resistance mediated by P-glycoprotein

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tomono, Takumi; Kajita, Masahiro; Yano, Kentaro

P-glycoprotein (P-gp) is an ATP-binding cassette protein involved in cancer multi-drug resistance (MDR). It has been reported that infection with some bacteria and viruses induces changes in the activities of various drug-metabolizing enzymes and transporters, including P-gp. Although human adenoviruses (Ad) cause the common cold, the effect of Ad infection on MDR in cancer has not been established. In this study, we investigated whether Ad infection is a cause of MDR in A549, H441 and HCC827 non-small-cell lung cancer (NSCLC) cell lines, using an Ad vector system. We found that Ad vector infection of NSCLC cell lines induced P-gp mRNAmore » expression, and the extent of induction was dependent on the number of Ad vector virus particles and the infection time. Heat-treated Ad vector, which is not infectious, did not alter P-gp mRNA expression. Uptake experiments with doxorubicin (DOX), a P-gp substrate, revealed that DOX accumulation was significantly decreased in Ad vector-infected A549 cells. The decrease of DOX uptake was blocked by verapamil, a P-gp inhibitor. Our results indicated that Ad vector infection of NSCLC cells caused MDR mediated by P-gp overexpression. The Ad vector genome sequence is similar to that of human Ad, and therefore human Ad infection of lung cancer patients may lead to chemoresistance in the clinical environment. -- Highlights: •Adenovirus vector infection induced P-gp mRNA expression in three NSCLC cell lines. •Adenovirus vector infection enhanced P-gp-mediated doxorubicin efflux from the cells. •The increase of P-gp was not mediated by nuclear receptors (PXR, CAR) or COX-2.« less

The blood-brain barrier in the cerebrum is the initial site for the Japanese encephalitis virus entering the central nervous system.

PubMed

Liu, Tsan-Hsiun; Liang, Li-Ching; Wang, Chien-Chih; Liu, Huei-Chung; Chen, Wei-June

2008-11-01

Japanese encephalitis (JE) virus is a member of the encephalitic flaviviruses and frequently causes neurological sequelae in a proportion of patients who survive the acute phase of the infection. In the present study, we molecularly identified viral infection in the brain of mice with rigidity of hindlimbs and/or abnormal gait, in which JE virus particles appeared within membrane-bound vacuoles of neurons throughout the central nervous system. Deformation of tight junctions (TJs) shown as dissociation of endothelial cells in capillaries, implying that the integrity of the blood-brain barrier (BBB) has been compromised by JE virus infection. BBB permeability evidently increased in the cerebrum, but not in the cerebellum, of JE virus-infected mice intravenously injected with the tracer of Evans blue dye. This suggests that the permeability of the BBB differentially changed in response to viral infection, leading to the entry of JE virions and/or putatively infected leukocytes from the periphery to the cerebrum as the initial site of infection in the central nervous system (CNS). Theoretically, the virus spread to the cerebellum soon after the cerebrum became infected.

Acute Systemic Infection with Dengue Virus Leads to Vascular Leakage and Death through Tumor Necrosis Factor-α and Tie2/Angiopoietin Signaling in Mice Lacking Type I and II Interferon Receptors.

PubMed

Phanthanawiboon, Supranee; Limkittikul, Kriengsak; Sakai, Yusuke; Takakura, Nobuyuki; Saijo, Masayuki; Kurosu, Takeshi

2016-01-01

Severe dengue is caused by host responses to viral infection, but the pathogenesis remains unknown. This is, in part, due to the lack of suitable animal models. Here, we report a non-mouse-adapted low-passage DENV-3 clinical isolate, DV3P12/08, derived from recently infected patients. DV3P12/08 caused a lethal systemic infection in type I and II IFN receptor KO mice (IFN-α/β/γR KO mice), which have the C57/BL6 background. Infection with DV3P12/08 induced a cytokine storm, resulting in severe vascular leakage (mainly in the liver, kidney and intestine) and organ damage, leading to extensive hemorrhage and rapid death. DV3P12/08 infection triggered the release of large amounts of TNF-α, IL-6, and MCP-1. Treatment with a neutralizing anti-TNF-α antibody (Ab) extended survival and reduced liver damage without affecting virus production. Anti-IL-6 neutralizing Ab partly prolonged mouse survival. The anti-TNF-α Ab suppressed IL-6, MCP-1, and IFN-γ levels, suggesting that the severe response to infection was triggered by TNF-α. High levels of TNF-α mRNA were expressed in the liver and kidneys, but not in the small intestine, of infected mice. Conversely, high levels of IL-6 mRNA were expressed in the intestine. Importantly, treatment with Angiopoietin-1, which is known to stabilize blood vessels, prolonged the survival of DV3P12/08-infected mice. Taken together, the results suggest that an increased level of TNF-α together with concomitant upregulation of Tie2/Angiopoietin signaling have critical roles in severe dengue infection.

Pravastatin inhibits farnesol production in Candida albicans and improves survival in a mouse model of systemic candidiasis.

PubMed

Tashiro, Masato; Kimura, Soichiro; Tateda, Kazuhiro; Saga, Tomoo; Ohno, Akira; Ishii, Yoshikazu; Izumikawa, Koichi; Tashiro, Takayoshi; Kohno, Shigeru; Yamaguchi, Keizo

2012-05-01

Candidemia remains a major cause of morbidity and mortality, especially in immunocompromised patients. A strategy of reducing virulence and virulence factors of Candida spp. is an attractive approach for the treatment of serious infections caused by these yeasts. Recently, farnesol has been reported to be a quorum-sensing autoinducer, as well as a virulence factor of C. albicans. In the present study, we examined the effects of pravastatin, a 3-hydroxy-3-methylglutaryl-CoA (HMG-CoA) reductase inhibitor on the in vitro production of farnesol. In addition, the synergistic effects of pravastatin with fluconazole (FLC) were examined in a mouse model of systemic infections. In vitro experiments demonstrated that pravastatin had synergistic activity with FLC as judged by fractional inhibitory concentration index (FICI) and suppression of farnesol production at sub-minimum inhibitory concentrations. Furthermore, significant improvement of survival in systemic infection models was shown with pravastatin supplementation. The survival benefits of pravastatin were correlated with reductions of fungal burden. These data suggest the potential of pravastatin as a supportive therapy against C. albicans infections. Synergistic antifungal activity and suppression of HMG-CoA reductase-associated Candida virulence factors, including farnesol, may explain, at least in part, the in vivo efficacy of pravastatin.

Effect of various concentrations of antibiotics on osteogenic cell viability and activity.

PubMed

Rathbone, Christopher R; Cross, Jessica D; Brown, Kate V; Murray, Clinton K; Wenke, Joseph C

2011-07-01

Infection is a common complication of open fractures. Systemic antibiotics often cause adverse events before eradication of infected bone occurs. The local delivery of antibiotics and the use of implants that deliver both growth factors and antimicrobials are ways to circumvent systemic toxicity while decreasing infection and to reach extremely high levels required to treat bacterial biofilms. When choosing an antibiotic for a local delivery system, one should consider the effect that the antibiotic has on cell viability and osteogenic activity. To address this concern, osteoblasts were treated with 21 different antibiotics over 8 concentrations from 0 to 5000 µg/ml. Osteoblast deoxyribonucleic acid content and alkaline phosphatase activity (ALP) were measured to determine cell number and osteogenic activity, respectively. Antibiotics that caused the greatest decrement include rifampin, minocycline, doxycycline, nafcillin, penicillin, ciprofloxacin, colistin methanesulfonate, and gentamicin; their cell number and ALP were significantly less than control at drug concentrations ≤ 200 µg/ml. Conversely, amikacin, tobramycin, and vancomycin were the least cytotoxic and did not appreciably affect cell number and ALP until very high concentrations were used. This comprehensive evaluation of numerous antibiotics' effects on osteoblast viability and activity will enable clinicians and researchers to choose the optimal antibiotic for treatment of infection and maintenance of healthy host bone. Copyright © 2011 Orthopaedic Research Society.

A case report of tinea pedis caused by Trichosporon faecale in Iran

PubMed Central

Fallahi, Ali akbar; Moazeni, Maryam; Noorbakhsh, Fatemeh; Kordbacheh, Parivash; Zaini, Farideh; Mirhendi, Hossein; Zeraati, Hojjat; Rezaie, Sassan

2012-01-01

Trichosporon species are known as the causative agents of cutaneous infections and are involved in systemic, localized, as well as disseminated mycoses particularly in immunocompromised patients. Here we report a case of tinea pedis infection caused by Trichosporon faecale in a healthy 29-year-old woman in the north of Iran. Macroscopic and microscopic characteristics using direct examination as well as culture method revealed the causative agent as Trichosporon species. Molecular analysis of the internal transcribed spacer region validated the initial result and indicated that this case of tinea pedis was caused by T. faecale. The patient was recovered after treatment with topical myconazole accompanied with oral fluconazole. PMID:24371737

Fatal primary meningoencephalitis caused by Naegleria fowleri.

PubMed

Shariq, Ali; Afridi, Faisal Iqbal; Farooqi, Badar Jahan; Ahmed, Sumaira; Hussain, Arif

2014-07-01

Naegleria fowleri is a free living parasite which habitats in fresh water reservoirs. It causes a fatal nervous system infection known as primary amoebic meningoencephalitis by invading through cribriform plate of nose and gaining entry into brain. We report a case of primary amoebic meningoencephalitis caused by Naegleria fowleri in Karachi, Pakistan, in a 42 years old male poultry farm worker having no history of swimming. Clinical course was fulminant and death occurred within one week of hospital admission. Naegleria fowleri was detected by wet mount technique in the sample of cerebrospinal fluid collected by lumbar puncture of patient. This is a serious problem and requires immediate steps to prevent general population to get affected by this lethal neurological infection.

Detection of cucumber green mottle mosaic virus-infected watermelon seeds using short wave infrared (SWIR) hyperspectral imaging system

USDA-ARS?s Scientific Manuscript database

The cucurbit diseases caused by cucumber green mottle mosaic virus (CGMMV) have led to a serious problem to growers and seed producers because it is difficult to prevent spreading through causal agent of seeds. Conventional detection methods for infected seed such as a biological, serological, and m...

The morbidity, mortality, and costs associated with Clostridium difficile infection.

PubMed

Kwon, Jennie H; Olsen, Margaret A; Dubberke, Erik R

2015-03-01

Clostridium difficile infection (CDI) is the most common cause of infectious health care-associated diarrhea and is a major burden to patients and the health care system. The incidence and severity of CDI remain at historically high levels. This article reviews the morbidity, mortality, and costs associated with CDI. Copyright © 2015 Elsevier Inc. All rights reserved.

Imaging of viral neuroinvasion in the zebrafish reveals that Sindbis and chikungunya viruses favour different entry routes

PubMed Central

Passoni, Gabriella; Langevin, Christelle; Palha, Nuno; Mounce, Bryan C.; Briolat, Valérie; Affaticati, Pierre; De Job, Elodie; Joly, Jean-Stéphane; Vignuzzi, Marco; Saleh, Maria-Carla; Herbomel, Philippe; Boudinot, Pierre

2017-01-01

ABSTRACT Alphaviruses, such as chikungunya virus (CHIKV) and Sindbis virus (SINV), are vector-borne pathogens that cause acute illnesses in humans and are sometimes associated with neuropathies, especially in infants and elderly patients. Little is known about their mechanism of entry into the central nervous system (CNS), even for SINV, which has been used extensively as a model for viral encephalopathies. We previously established a CHIKV infection model in the optically transparent zebrafish larva; here we describe a new SINV infection model in this host. We imaged in vivo the onset and progression of the infection caused by intravenous SINV inoculation. Similar to that described for CHIKV, infection in the periphery was detected early and was transient, whereas CNS infection started at later time points and was persistent or progressive. We then tested the possible mechanisms of neuroinvasion by CHIKV and SINV. Neither virus relied on macrophage-mediated transport to access the CNS. CHIKV, but not SINV, always infects endothelial cells of the brain vasculature. By contrast, axonal transport was much more efficient with SINV than CHIKV, both from the periphery to the CNS and between neural tissues. Thus, the preferred mechanisms of neuroinvasion by these two related viruses are distinct, providing a powerful imaging-friendly system to compare mechanisms and prevention methods of encephalopathies. PMID:28483796

Immune Function and Reactivation of Latent Viruses

NASA Technical Reports Server (NTRS)

Butel, Janet S.

1999-01-01

A major concern associated with long-duration space flight is the possibility of infectious diseases posing an unacceptable medical risk to crew members. One major hypothesis addressed in this project is that space flight will cause alterations in the immune system that will allow latent viruses that are endogenous in the human population to reactivate and shed to higher levels than normal, which may affect the health of crew members. The second major hypothesis being examined is that the effects of space flight will alter the mucosal immune system, the first line of defense against many microbial infections, including herpesviruses, polyomaviruses, and gastroenteritis viruses, rendering crew members more susceptible to virus infections across the mucosa. We are focusing the virus studies on the human herpesviruses and polyomaviruses, important pathogens known to establish latent infections in most of the human population. Both primary infection and reactivation from latent infection with these groups of viruses (especially certain herpesviruses) can cause a variety of illnesses that result in morbidity and, occasionally, mortality. Both herpesviruses and polyomaviruses have been associated with human cancer, as well. Effective vaccines exist for only one of the eight known human herpesviruses and available antivirals are of limited use. Whereas normal individuals display minimal consequences from latent viral infections, events which alter immune function (such as immunosuppressive therapy following solid organ transplantation) are known to increase the risk of complications as a result of viral reactivations.

Safety and tolerability of a live oral Salmonella typhimurium vaccine candidate in SIV-infected nonhuman primates.

PubMed

Ault, Alida; Tennant, Sharon M; Gorres, J Patrick; Eckhaus, Michael; Sandler, Netanya G; Roque, Annelys; Livio, Sofie; Bao, Saran; Foulds, Kathryn E; Kao, Shing-Fen; Roederer, Mario; Schmidlein, Patrick; Boyd, Mary Adetinuke; Pasetti, Marcela F; Douek, Daniel C; Estes, Jacob D; Nabel, Gary J; Levine, Myron M; Rao, Srinivas S

2013-12-02

Nontyphoidal Salmonella (NTS) serovars are a common cause of acute food-borne gastroenteritis worldwide and can cause invasive systemic disease in young infants, the elderly, and immunocompromised hosts, accompanied by high case fatality. Vaccination against invasive NTS disease is warranted where the disease incidence and mortality are high and multidrug resistance is prevalent, as in sub-Saharan Africa. Live-attenuated vaccines that mimic natural infection constitute one strategy to elicit protection. However, they must particularly be shown to be adequately attenuated for consideration of immunocompromised subjects. Accordingly, we examined the safety and tolerability of an oral live attenuated Salmonella typhimurium vaccine candidate, CVD 1921, in an established chronic simian immunodeficiency virus (SIV)-infected rhesus macaque model. We evaluated clinical parameters, histopathology, and measured differences in mucosal permeability to wild-type and vaccine strains. Compared to the wild-type S. typhimurium strain I77 in both SIV-infected and SIV-uninfected nonhuman primate hosts, this live-attenuated vaccine shows reduced shedding and systemic spread, exhibits limited pathological disease manifestations in the digestive tract, and induces low levels of cellular infiltration in tissues. Furthermore, wild-type S. typhimurium induces increased intestinal epithelial damage and permeability, with infiltration of neutrophils and macrophages in both SIV-infected and SIV-uninfected nonhuman primates compared to the vaccine strain. Based on shedding, systemic spread, and histopathology, the live-attenuated S. typhimurium strain CVD 1921 appears to be safe and well-tolerated in the nonhuman primate model, including chronically SIV-infected rhesus macaques. Copyright © 2013. Published by Elsevier Ltd.

[Dermatomycoses due to pets and farm animals : neglected infections?].

PubMed

Nenoff, P; Handrick, W; Krüger, C; Vissiennon, T; Wichmann, K; Gräser, Y; Tchernev, G

2012-11-01

Dermatomycoses due to contact with pets and livestock frequently affect children and young adults. Zoophilic dermatophytes are the main important causative agents. It has long been known that the often high inflammatory dermatophytoses of the skin and the scalp are caused mostly by Microsporum canis. Due to an absence of an obligation for reporting fungal infections of the skin to the Public Health Office in Germany, an unnoticed but significant change in responsible pathogens has occurred. Today an increasing number of infections due to zoophilic strains of Trichophyton interdigitale (formerly Trichophyton mentagrophytes) and Trichophyton species of Arthroderma benhamiae are found. The latter mentioned dermatophyte is the anamorph species of the teleomorph Arthroderma benhamiae, which originally was isolated in the Far East (Japan). Source of infection of these dermatophytes are small rodents, in particular guinea pigs. These animals are bought in pet shops by the parents of those children who later are affected by the fungal infection. The coincidental purchase of the relevant fungal pathogen is not obvious to the parents. As a consequence, highly contagious dermatophytoses occur, often tinea capitis sometimes with kerion formation. Further dermatophytes should be considered as cause of a zoophilic dermatomycosis. Both Trichophyton verrucosum, the cause of the ringworm in cattle, and Trichophyton erinacei following contact to hedgehogs are worthy of note. Yeasts cannot be ignored as cause of dermatomycosis, especially Malassezia pachydermatis, the only non-lipophilic species within the genus Malassezia, which can be transferred from dog to men. Cryptococcus neoformans also comes from animal sources. The mucous yeast occurs in bird's dropping, and it causes both pulmonary and central nervous system infections, but also primary and secondary cutaneous cryptococcosis in immunocompromised patients (HIV/AIDS) as possible consequence after contact to these animals.

The chicken as a natural model for extraintestinal infections caused by avian pathogenic Escherichia coli (APEC).

PubMed

Antão, Esther-Maria; Glodde, Susanne; Li, Ganwu; Sharifi, Reza; Homeier, Timo; Laturnus, Claudia; Diehl, Ines; Bethe, Astrid; Philipp, Hans-C; Preisinger, Rudolf; Wieler, Lothar H; Ewers, Christa

2008-01-01

E. coli infections in avian species have become an economic threat to the poultry industry worldwide. Several factors have been associated with the virulence of E. coli in avian hosts, but no specific virulence gene has been identified as being entirely responsible for the pathogenicity of avian pathogenic E. coli (APEC). Needless to say, the chicken would serve as the best model organism for unravelling the pathogenic mechanisms of APEC, an extraintestinal pathogen. Five-week-old white leghorn SPF chickens were infected intra-tracheally with a well characterized APEC field strain IMT5155 (O2:K1:H5) using different doses corresponding to the respective models of infection established, that is, the lung colonization model allowing re-isolation of bacteria only from the lung but not from other internal organs, and the systemic infection model. These two models represent the crucial steps in the pathogenesis of APEC infections, including the colonization of the lung epithelium and the spread of bacteria throughout the bloodstream. The read-out system includes a clinical score, pathomorphological changes and bacterial load determination. The lung colonization model has been established and described for the first time in this study, in addition to a comprehensive account of a systemic infection model which enables the study of severe extraintestinal pathogenic E. coli (ExPEC) infections. These in vivo models enable the application of various molecular approaches to study host-pathogen interactions more closely. The most important application of such genetic manipulation techniques is the identification of genes required for extraintestinal virulence, as well as host genes involved in immunity in vivo. The knowledge obtained from these studies serves the dual purpose of shedding light on the nature of virulence itself, as well as providing a route for rational attenuation of the pathogen for vaccine construction, a measure by which extraintestinal infections, including those caused by APEC, could eventually be controlled and prevented in the field.

Detection of Candida species by nested PCR method in one-humped camels (Camelus dromedarius).

PubMed

Parin, Ugur; Erbas, Goksel; Kirkan, Sukru; Savasan, Serap; Tugba Yuksel, H; Balat, Gamze

2018-02-01

Systemic fungal diseases are the infections caused by false treatment protocols and generally are not taken into consideration especially in the veterinary field. One-humped camels are found in the western side of the Aegean region of our country and bred for wrestling. The aim of this study is the application of diagnosing systemic fungi infection from camel blood samples by the PCR method. In this study, specific primers for DNA topoisomerase II gene sequences were used. As a result, a systemic fungal infection was detected by the nested PCR method from 10 (20%) out of 50 DNA samples taken from camels located on the western side of the Aegean region. In this study, 3 (30%) samples were identified as Candida albicans, 3 (30%) samples were identified as C. glabrata, and 4 (40%) samples were identified as C. parapsilosis. In conclusion, the 20% positive systemic fungal infection rate in one-humped camels observed in the present study showed that the systemic fungal infections are not taken into considerations in veterinary medicine. Further studies are suggested in order to obtain and to maintain extensive data for systemic fungal diseases in our country for one-humped camels.

[Invasive infection caused Streptococcus group A and streptococcal toxic shock syndrome].

PubMed

Danilova, T A

2001-01-01

Modern data on the etiology and pathogenesis of invasive streptococcal infection and the syndrome of streptococcal toxic shock are presented. In the course of the last 10-15 years essential changes in the system of interaction of group A streptococci and the macroorganism have been noted. The growth of morbidity in severe invasive forms of streptococcal infection with different clinical manifestations, including the syndrome of toxic shock, is observed. Most often this disease develops in elderly people, making up a group of risk, but sometimes affects healthy young people. Different pathogenicity factors of streptococci, capable of inducing the development of infection, are analyzed. Special attention is given to superantigens: pyrogenic toxins and M-protein. The suggestion that the development of the disease is seemingly linked with the state of specific protective immunity is substantiated. In spite of achievements in the field of the microbiology and immunology of group A streptococci, the causes of the appearance and development of invasive streptococcal infection have not yet been determined.

Penetration of equine leukocytes by merozoites of Sarcocystis neurona.

PubMed

Lindsay, David S; Mitchell, Sheila M; Yang, Jibing; Dubey, J P; Gogal, Robert M; Witonsky, Sharon G

2006-06-15

Horses are considered accidental hosts for Sarcocystis neurona and they often develop severe neurological disease when infected with this parasite. Schizont stages develop in the central nervous system (CNS) and cause the neurological lesions associated with equine protozoal myeloencephalitis. The present study was done to examine the ability of S. neurona merozoites to penetrate and develop in equine peripheral blood leukocytes. These infected host cells might serve as a possible transport mechanism into the CNS. S. neurona merozoites penetrated equine leukocytes within 5 min of co-culture. Infected leukocytes were usually monocytes. Infected leukocytes were present up to the final day of examination at 3 days. Up to three merozoites were present in an infected monocyte. No development to schizont stages was observed. All stages observed were in the host cell cytoplasm. We postulate that S. neurona merozoites may cross the blood brain barrier hidden inside leukocytes. Once inside the CNS these merozoites can egress and invade additional cells and cause encephalitis.

Malnutrition and Gastrointestinal and Respiratory Infections in Children: A Public Health Problem

PubMed Central

Rodríguez, Leonor; Cervantes, Elsa; Ortiz, Rocío

2011-01-01

Infectious disease is the major cause of morbidity and mortality in developing countries, particularly in children. Increasing evidence suggests that protein-calorie malnutrition is the underlying reason for the increased susceptibility to infections observed in these areas. Moreover, certain infectious diseases also cause malnutrition, which can result in a vicious cycle. Malnutrition and bacterial gastrointestinal and respiratory infections represent a serious public health problem. The increased incidence and severity of infections in malnourished children is largely due to the deterioration of immune function; limited production and/or diminished functional capacity of all cellular components of the immune system have been reported in malnutrition. In this review, we analyze the cyclical relationship between malnutrition, immune response dysfunction, increased susceptibility to infectious disease, and metabolic responses that further alter nutritional status. The consequences of malnutrition are diverse and included: increased susceptibility to infection, impaired child development, increased mortality rate and individuals who come to function in suboptimal ways. PMID:21695035

Attenuation of virus production at high multiplicities of infection in Aureococcus anophagefferens

DOE Office of Scientific and Technical Information (OSTI.GOV)

Brown, Christopher M.; Bidle, Kay D., E-mail: bidle@marine.rutgers.edu

2014-10-15

Infection dynamics (saturation kinetics, infection efficiency, adsorption and burst size) for the Aureococcus anophagefferens-Brown Tide virus (AaV) system were investigated using susceptible and resistant strains. Adsorption assays revealed that virus affinity to the cell surface is a key determinant of infectivity. Saturation of infection occurred at a multiplicity of infection (MOI) of 8 viruses per host and resulted in ∼90–95% of infected cells, with burst sizes ranging from 164 to 191. Insight from the AaV genome implicates recycling of host nucleotides rather than de novo synthesis as a constraint on viral replication. Viral yields and mean burst sizes were significantlymore » diminished with increasing MOI. This phenomenon, which was reminiscent of phage-induced ‘lysis from without’, appeared to be caused by viral contact and was unrelated to bacteria, signaling/toxic compounds, or defective interfering viruses. We posit that high-MOI effects attenuate viral proliferation in natural systems providing a negative feedback on virus-induced bloom collapse.« less

New Paradigms for the Study of Ocular Alphaherpesvirus Infections: Insights into the Use of Non-Traditional Host Model Systems

PubMed Central

Ledbetter, Eric C.; Van de Walle, Gerlinde R.

2017-01-01

Ocular herpesviruses, most notably human alphaherpesvirus 1 (HSV-1), canid alphaherpesvirus 1 (CHV-1) and felid alphaherpesvirus 1 (FHV-1), infect and cause severe disease that may lead to blindness. CHV-1 and FHV-1 have a pathogenesis and induce clinical disease in their hosts that is similar to HSV-1 ocular infections in humans, suggesting that infection of dogs and cats with CHV-1 and FHV-1, respectively, can be used as a comparative natural host model of herpesvirus-induced ocular disease. In this review, we discuss both strengths and limitations of the various available model systems to study ocular herpesvirus infection, with a focus on the use of these non-traditional virus-natural host models. Recent work has demonstrated the robustness and reproducibility of experimental ocular herpesvirus infections in dogs and cats, and, therefore, these non-traditional models can provide additional insights into the pathogenesis of ocular herpesvirus infections. PMID:29156583

Ganciclovir Injection

MedlinePlus

Ganciclovir injection is used to treat cytomegalovirus (CMV) retinitis (eye infection that can cause blindness) in people whose immune system is not working normally, including those people who have acquired immunodeficiency ...

Type 1 Interferons and NK Cells Limit Murine Cytomegalovirus Escape from the Lymph Node Subcapsular Sinus

PubMed Central

Bruce, Kimberley; Lawler, Clara; Cardin, Rhonda D.

2016-01-01

Cytomegaloviruses (CMVs) establish chronic, systemic infections. Peripheral infection spreads via lymph nodes, which are also a focus of host defence. Thus, this is a point at which systemic infection spread might be restricted. Subcapsular sinus macrophages (SSM) captured murine CMV (MCMV) from the afferent lymph and poorly supported its replication. Blocking the type I interferon (IFN-I) receptor (IFNAR) increased MCMV infection of SSM and of the fibroblastic reticular cells (FRC) lining the subcapsular sinus, and accelerated viral spread to the spleen. Little splenic virus derived from SSM, arguing that they mainly induce an anti-viral state in the otherwise susceptible FRC. NK cells also limited infection, killing infected FRC and causing tissue damage. They acted independently of IFN-I, as IFNAR blockade increased NK cell recruitment, and NK cell depletion increased infection in IFNAR-blocked mice. Thus SSM restricted MCMV infection primarily though IFN-I, with NK cells providing a second line of defence. The capacity of innate immunity to restrict MCMV escape from the subcapsular sinus suggested that enhancing its recruitment might improve infection control. PMID:27926941

An in-situ infection detection sensor coating for urinary catheters

PubMed Central

Milo, Scarlet; Thet, Naing Tun; Liu, Dan; Nzakizwanayo, Jonathan; Jones, Brian V.; Jenkins, A. Toby A.

2016-01-01

We describe a novel infection-responsive coating for urinary catheters that provides a clear visual early warning of Proteus mirabilis infection and subsequent blockage. The crystalline biofilms of P. mirabilis can cause serious complications for patients undergoing long-term bladder catheterisation. Healthy urine is around pH 6, bacterial urease increases urine pH leading to the precipitation of calcium and magnesium deposits from the urine, resulting in dense crystalline biofilms on the catheter surface that blocks urine flow. The coating is a dual layered system in which the lower poly(vinyl alcohol) layer contains the self-quenching dye carboxyfluorescein. This is capped by an upper layer of the pH responsive polymer poly(methyl methacrylate-co-methacrylic acid) (Eudragit S100®). Elevation of urinary pH (>pH 7) dissolves the Eudragit layer, releasing the dye to provide a clear visual warning of impending blockage. Evaluation of prototype coatings using a clinically relevant in vitro bladder model system demonstrated that coatings provide up to 12 h advanced warning of blockage, and are stable both in the absence of infection, and in the presence of species that do not cause catheter blockage. At the present time, there are no effective methods to control these infections or provide warning of impending catheter blockage. PMID:26945183

Comparison of Pratylenchus penetrans Infection and Maladera castanea Feeding on Strawberry Root Rot

PubMed Central

LaMondia, J. A.; Cowles, R. S.

2005-01-01

The interaction of lesion nematodes, black root rot disease caused by Rhizoctonia fragariae, and root damage caused by feeding of the scarab larva, Maladera castanea, was determined in greenhouse studies. Averaged over all experiments after 12 weeks, root weight was reduced 13% by R. fragariae and 20% by M. castanea. The percentage of the root system affected by root rot was increased by inoculation with either R. fragariae (35% more disease) or P. penetrans (50% more disease) but was unaffected by M. castanea. Rhizoctonia fragariae was isolated from 9.2% of the root segments from plants not inoculated with R. fragariae. The percentage of R. fragariae-infected root segments was increased 3.6-fold by inoculation with R. fragariae on rye seeds. The presence of P. penetrans also increased R. fragariae root infection. The type of injury to root systems was important in determining whether roots were invaded by R. fragariae and increased the severity of black root rot. Pratylenchus penetrans increased R. fragariae infection and the severity of black root rot. Traumatic cutting action by Asiatic garden beetle did not increase root infection or root disease by R. fragariae. Both insects and diseases need to be managed to extend the productive life of perennial strawberry plantings. PMID:19262852

Genetic variants of innate immune receptors and infections after liver transplantation

PubMed Central

Sanclemente, Gemma; Moreno, Asuncion; Navasa, Miquel; Lozano, Francisco; Cervera, Carlos

2014-01-01

Infection is the leading cause of complication after liver transplantation, causing morbidity and mortality in the first months after surgery. Allograft rejection is mediated through adaptive immunological responses, and thus immunosuppressive therapy is necessary after transplantation. In this setting, the presence of genetic variants of innate immunity receptors may increase the risk of post-transplant infection, in comparison with patients carrying wild-type alleles. Numerous studies have investigated the role of genetic variants of innate immune receptors and the risk of complication after liver transplantation, but their results are discordant. Toll-like receptors and mannose-binding lectin are arguably the most important studied molecules; however, many other receptors could increase the risk of infection after transplantation. In this article, we review the published studies analyzing the impact of genetic variants in the innate immune system on the development of infectious complications after liver transplantation. PMID:25170199

Parasitic scabies mites and associated bacteria joining forces against host complement defence.

PubMed

Swe, P M; Reynolds, S L; Fischer, K

2014-11-01

Scabies is a ubiquitous and contagious skin disease caused by the parasitic mite Sarcoptes scabiei Epidemiological studies have identified scabies as a causative agent for secondary skin infections caused by Staphylococcus aureus and Streptococcus pyogenes. This is an important notion, as such bacterial infections can lead to serious downstream life-threatening complications. As the complement system is the first line of host defence that confronts invading pathogens, both the mite and bacteria produce a large array of molecules that inhibit the complement cascades. It is hypothesised that scabies mite complement inhibitors may play an important role in providing a favourable micro-environment for the establishment of secondary bacterial infections. This review aims to bring together the current literature on complement inhibition by scabies mites and bacteria associated with scabies and to discuss the proposed molecular link between scabies and bacterial co-infections. © 2014 John Wiley & Sons Ltd.

Rare Case of Aspergillus ochraceus Osteomyelitis of Calcaneus Bone in a Patient with Diabetic Foot Ulcers.

PubMed

Babamahmoodi, Farhang; Shokohi, Tahereh; Ahangarkani, Fatemeh; Nabili, Mojtaba; Afzalian Ashkezari, Elham; Alinezhad, Sosan

2015-01-01

Diabetes is the most common metabolic disease in humans. One of the major complications of the disease is foot ulcer that is prone to infection. The most common causes of infection which have been reported in these patients are bacteria and fungi such as Candida, Aspergillus, and Rhizopus species. We report one such rare case with calcaneal osteomyelitis caused by Aspergillus ochraceus in a patient with diabetic foot osteomyelitis. The case was a 68-year-old male with a history of type II diabetes for 2 years. The patient had two ulcers on the right heel bones for the past 6 months with no significant improvement. One of the most important predisposing factors to infectious diseases, especially opportunistic fungal infection, is diabetes mellitus. Aspergillus species can involve bony tissue through vascular system, direct infection, and trauma. Proper and early diagnosis and treatment of diabetic foot infection can reduce or prevent complications, such as osteomyelitis and amputation. The annual examination of feet for skin and nail lesion, sensation, anatomical changes, and vascular circulation can be useful for prevention and control of infection.

Rare Case of Aspergillus ochraceus Osteomyelitis of Calcaneus Bone in a Patient with Diabetic Foot Ulcers

PubMed Central

Babamahmoodi, Farhang; Shokohi, Tahereh; Ahangarkani, Fatemeh; Nabili, Mojtaba; Afzalian Ashkezari, Elham; Alinezhad, Sosan

2015-01-01

Diabetes is the most common metabolic disease in humans. One of the major complications of the disease is foot ulcer that is prone to infection. The most common causes of infection which have been reported in these patients are bacteria and fungi such as Candida, Aspergillus, and Rhizopus species. We report one such rare case with calcaneal osteomyelitis caused by Aspergillus ochraceus in a patient with diabetic foot osteomyelitis. The case was a 68-year-old male with a history of type II diabetes for 2 years. The patient had two ulcers on the right heel bones for the past 6 months with no significant improvement. One of the most important predisposing factors to infectious diseases, especially opportunistic fungal infection, is diabetes mellitus. Aspergillus species can involve bony tissue through vascular system, direct infection, and trauma. Proper and early diagnosis and treatment of diabetic foot infection can reduce or prevent complications, such as osteomyelitis and amputation. The annual examination of feet for skin and nail lesion, sensation, anatomical changes, and vascular circulation can be useful for prevention and control of infection. PMID:26064128

Multi-spectral fluorescent reporter influenza viruses (Color-flu) as powerful tools for in vivo studies

PubMed Central

Fukuyama, Satoshi; Katsura, Hiroaki; Zhao, Dongming; Ozawa, Makoto; Ando, Tomomi; Shoemaker, Jason E.; Ishikawa, Izumi; Yamada, Shinya; Neumann, Gabriele; Watanabe, Shinji; Kitano, Hiroaki; Kawaoka, Yoshihiro

2015-01-01

Seasonal influenza A viruses cause annual epidemics of respiratory disease; highly pathogenic avian H5N1 and the recently emerged H7N9 viruses cause severe infections in humans, often with fatal outcomes. Although numerous studies have addressed the pathogenicity of influenza viruses, influenza pathogenesis remains incompletely understood. Here we generate influenza viruses expressing fluorescent proteins of different colours (‘Color-flu’ viruses) to facilitate the study of viral infection in in vivo models. On adaptation to mice, stable expression of the fluorescent proteins in infected animals allows their detection by different types of microscopy and by flow cytometry. We use this system to analyse the progression of viral spread in mouse lungs, for live imaging of virus-infected cells, and for differential gene expression studies in virus antigen-positive and virus antigen-negative live cells in the lungs of Color-flu-infected mice. Collectively, Color-flu viruses are powerful tools to analyse virus infections at the cellular level in vivo to better understand influenza pathogenesis. PMID:25807527

Aspergillosis.

PubMed

Bodey, G P; Vartivarian, S

1989-05-01

Aspergillus spores are ubiquitous in the environment and may become concentrated in hospital ventilation systems. Colonization in normal hosts can lead to allergic diseases ranging from asthma to allergic bronchopulmonary aspergillosis. Normal hosts rarely develop invasive disease, which is primarily an infection of severely immunocompromised patients. The major predisposing factors for infection include prolonged neutropenia, chronic administration of adrenal corticosteroids, the insertion of prosthetic devices, and tissue damage due to prior infection or trauma. Since Aspergillus spp. are respiratory pathogens, the most common form of infection is pneumonia followed by sinusitis. Patients with preexistant cavitary disease may develop noninvasive aspergillomas. Most infections are caused by Aspergillus fumigatus. The organism is capable of invading across all natural barriers, including cartilage and bone. It has a propensity for invading blood vessels causing thrombosis and infarction. The diagnosis of pulmonary infection is usually difficult to establish because the organism is seldom cultured from sputum and can represent contamination in some cases. Therapy is immunocompromised hosts is less than satisfactory and amphotericin B is the only agent with significant activity. There is anecdotal evidence to suggest that the addition of 5-fluorocytosine to amphotericin B may be beneficial.

[A Case of Hyperammonemia Caused by Urinary Tract Infection Due to Urease-Producing Bacteria].

PubMed

Emura, Masahiro; Tsuchihashi, Kazunari; Shimizu, Yosuke; Kanamaru, Sojun; Matoba, Shun; Ito, Noriyuki

2016-08-01

We present here a rare case of hyperammonemia without liver dysfunction or portal-systemic shunting. The patient was an 80-year-old woman with a history of neurogenic bladder. She was admitted to a nearby hospital for vomiting, diarrhea and consciousness disturbance. Two days after admission, she was transferred to our hospital because of persistant consciousness disturbance. Laboratory data revealed hyperammonemia, but there was no indication of liver dysfunction. Moreover abdominal computed tomography did not reveal any clear finding of liver disease or portal-systemic shunting, but we noted multiple large bladder diverticula. Antibiotic therapy, tracheal intubation, ventilator management and bladder catheterization were performed. The patient's level of consciousness improved rapidly. Urinary culture revealed Bacteroides ureolyticus (urease-producing bacteria). The patient was diagnosed with hyperammonemia and a urinary tract infection due to urease-producing bacteria. Thus, physicians should be aware that obstructive urinary tract infections due to urease-producing bacteria can also be the cause of hyperammonemia.

Chronic infection with Mycobacterium lepraemurium induces alterations in the hippocampus associated with memory loss.

PubMed

Becerril-Villanueva, Enrique; Ponce-Regalado, María Dolores; Pérez-Sánchez, Gilberto; Salazar-Juárez, Alberto; Arreola, Rodrigo; Álvarez-Sánchez, María Elizbeth; Juárez-Ortega, Mario; Falfán-Valencia, Ramcés; Hernández-Pando, Rogelio; Morales-Montor, Jorge; Pavón, Lenin; Rojas-Espinosa, Oscar

2018-06-13

Murine leprosy, caused by Mycobacterium lepraemurium (MLM), is a chronic disease that closely resembles human leprosy. Even though this disease does not directly involve the nervous system, we investigated a possible effect on working memory during this chronic infection in Balb/c mice. We evaluated alterations in the dorsal region of the hippocampus and measured peripheral levels of cytokines at 40, 80, and 120 days post-infection. To evaluate working memory, we used the T-maze while a morphometric analysis was conducted in the hippocampus regions CA1, CA2, CA3, and dentate gyrus (DG) to measure morphological changes. In addition, a neurochemical analysis was performed by HPLC. Our results show that, at 40 days post-infection, there was an increase in the bacillary load in the liver and spleen associated to increased levels of IL-4, working memory deterioration, and changes in hippocampal morphology, including degeneration in the four subregions analyzed. Also, we found a decrease in neurotransmitter levels at the same time of infection. Although MLM does not directly infect the nervous system, these findings suggest a possible functional link between the immune system and the central nervous system.

Control of parasites in cultured marine finfishes in Southeast Asia--an overview.

PubMed

Seng, L T

1997-10-01

Mariculture in Southeast Asia began in the 1970s and expanded rapidly during the 1980s, with the commercial hatchery production of the seabass Lates calcarifer. Other important cultured species were Epinephelus coioides, Epinephelus malabaricus, Lutjanus johni, and Lutjanus argentimaculatus. Intensification in the polyculture of these species and the large-scale international movement of fingerlings or juveniles, as well as the rapid expansion and concentration of fish farms, have caused severe problems resulting from parasitic infections. Infections in maricultured fish are predominantly caused by monoxenous parasites, in particular the capsalid and diplectanid monogeneans. Heteroxenous blood parasites also successfully maintained transmission in the culture system despite their requirement for an intermediate host. Prophylactic chemical treatments helped to reduce parasitic infection but did not eliminate them and once introduced into the floating netcage culture system, these parasites managed to maintain their transmission successfully. Despite the current lack of information regarding the biology of many parasites affecting cultured marine fishes, it nevertheless is possible to develop methodologies to produce an integrated health management system specifically designed to the needs of the mariculture practiced in the Southeast Asian region. This system is important and should include a sequence of prophylaxes, adequate nutrition, sanitation, immunization and an effective system of marketing for farmed fishes.

Prevention and cure of systemic Escherichia coli K1 infection by modification of the bacterial phenotype.

PubMed

Mushtaq, Naseem; Redpath, Maria B; Luzio, J Paul; Taylor, Peter W

2004-05-01

Escherichia coli is a common cause of meningitis and sepsis in the newborn infant, and the large majority of isolates from these infections produce a polysialic acid (PSA) capsular polysaccharide, the K1 antigen, that protects the bacterial cell from immune attack. We determined whether a capsule-depolymerizing enzyme, by removing this protective barrier, could alter the outcome of systemic infection in an animal model. Bacteriophage-derived endosialidase E (endoE) selectively degrades the PSA capsule on the surface of E. coli K1 strains. Intraperitoneal administration of small quantities of recombinant endoE (20 micro g) to 3-day-old rats, colonized with a virulent strain of K1, prevented bacteremia and death from systemic infection. The enzyme had no effect on the viability of E. coli strains but sensitized strains expressing PSA to killing by the complement system. This study demonstrates the potential therapeutic efficacy of agents that cure infections by modification of the bacterial phenotype rather than by killing or inhibition of growth of the pathogen.

Preventive and therapeutic challenges in combating Zika virus infection: are we getting any closer?

PubMed

Singh, Meera V; Weber, Emily A; Singh, Vir B; Stirpe, Nicole E; Maggirwar, Sanjay B

2017-06-01

The neuroteratogenic nature of Zika Virus (ZIKV) infection has converted what would have been a tropical disease into a global threat. Zika is transmitted vertically via infected placental cells especially in the first and second trimesters. In the developing central nervous system (CNS), ZIKV can infect and induce apoptosis of neural progenitor cells subsequently causing microcephaly as well as other neuronal complications in infants. Its ability to infect multiple cell types (placental, dermal, and neural) and increased environmental stability as compared to other flaviviruses (FVs) has broadened the transmission routes for ZIKV infection from vector-mediated to transmitted via body fluids. To further complicate the matters, it is genetically similar (about 40%) with the four serotypes of dengue virus (DENV), so much so that it can almost be called a fifth DENV serotype. This homology poses the risk of causing cross-reactive immune responses and subsequent antibody-dependent enhancement (ADE) of infection in case of secondary infections or for immunized individuals. All of these factors complicate the development of a single preventive vaccine candidate or a pharmacological intervention that will completely eliminate or cure ZIKV infection. We discuss all of these factors in detail in this review and conclude that a combinatorial approach including immunization and treatment might prove to be the winning strategy.

[Vectorial and congenital transmission of Trypanosoma cruzi in Las Lomitas, Formosa].

PubMed

Sosa-Estani, Sergio; Dri, Lucía; Touris, Cecilia; Abalde, Sergio; Dell'arciprete, Ana; Braunstein, Jose

2009-01-01

Chagas disease, caused by Trypanosoma cruzi, is a major cause of morbidity and mortality in Latin America. The objective of this study was to describe the rate of infestation in four aboriginal communities in Las Lomitas (Great Chaco Region), Formosa, Argentina; the rate of infection in children residing in these communities, in blood donors and in pregnant women who received care at the Hospital Las Lomitas, as well as the rate of congenital infection in children born to women infected during the study period. The rate of infestation of 172 households evaluated in 2006 reached 32%. Prevalence of infection among 445 people was 17.5% and in children under 5 years old it was 8.6%. The rate of infection reached 18.6% in blood donors and 29.1% in pregnant women. The rate of infection among 47 children born to infected women, and living in residences under vectorial surveillance was 17.0%. These infections were considered as congenital. This study showed indexes compatible with active vectorial transmission at the beginning. After vectorial control with insecticides the infestation rate has been reduced to 3.3%. The local health system has introduced high impact procedures of primary and secondary prevention in order to prevent new cases and to treat infected people.

Infection and stillbirth.

PubMed

McClure, Elizabeth M; Goldenberg, Robert L

2009-08-01

Infection may cause stillbirth by several mechanisms, including direct infection, placental damage, and severe maternal illness. Various organisms have been associated with stillbirth, including many bacteria, viruses, and protozoa. In developed countries, between 10% and 25% of stillbirths may be caused by an infection, whereas in developing countries, which have much higher stillbirth rates, the contribution of infection is much greater. In developed countries, ascending bacterial infection, both before and after membrane rupture, with organisms such as Escherichia coli, group B streptococci, and Ureaplasma urealyticum is usually the most common infectious cause of stillbirth. However, in areas where syphilis is prevalent, up to half of all stillbirths may be caused by this infection alone. Malaria may be an important cause of stillbirth in women infected for the first time in pregnancy. The two most important viral causes of stillbirth are parvovirus and Coxsackie virus, although a number of other viral infections appear to be causal. Toxoplasma gondii, Listeria monocytogenes, and the organisms that cause leptospirosis, Q fever, and Lyme disease have all been implicated as etiologic for stillbirth. In certain developing countries, the stillbirth rate is high and the infection-related component so great that achieving a substantial reduction in stillbirth should be possible by reducing maternal infections. However, because infection-related stillbirth is uncommon in developed countries, and because those that do occur are caused by a wide variety of organisms, reducing this etiologic component of stillbirth much further will be difficult.

[Fungal keratitis caused by Scedosporium apiospermum: first report from Turkey-comment].

PubMed

Atalay, Mustafa Altay; Koc, Ayşe Nedret

2014-04-01

Scedosporium apiospermum is a saprophytic fungus which is isolated worldwide in soil, fertilizers, polluted water, rotten vegetables, and other natural environments. It is the cause of mycetoma, a subcutaneous infection, characterized by granule formation. It may also cause severe local or diffuse infections in immunosuppressive patients. S.apiospermum-induced arthritis, endocarditis, keratitis, scleritis, endophthalmitis, meningitis, osteomyelitis, otomycosis, onychomycosis, chronic prostatitis, peritonitis, esophagitis, renal infection, and hepatosplenic abscess have been previously reported in the literature. Possible risk factors of fungal keratitis, one of the major causes of fungal ocular infection, include ocular injury, long-term therapy with topical or systemic steroids, immunosuppressive agents, and underlying diseases such as pre-existing corneal surface abnormality and diabetes mellitus, and wearing contact lenses. We paid great attention to the case report presented by Kalkan Akçay E et al. titled "Fungal keratitis caused by Scedosporium apiospermum: first report from Turkey", which was published in the October 2013 issue of Bulletin of Microbiology [Mikrobiyol Bul 2013; 47(4): 727-33]. Although it is deemed as the first case report of S.apiospermum-related fungal keratitis in Turkey, there were several previous case reports of ocular infections associated with this type of fungus in Turkey, including those of Yucel A titled "An eye mycosis caused by Scedosporium apiospermum (Monosporium apiospermum)" published in 1989, Kiratli et al. titled "Scedosporium apiospermum chorioretinitis" in 2001, Saracli et al. titled "Scedosporium apiospermum keratitis treated with itraconazole" in 2003 and Erdem et al. titled "Clinical follow up of a keratomycosis case with total corneal melting" in 2005. In conclusion, it should be highlighted that the report of Kalkan Akcay et al. is not the first case report of Scedosporium apiospermum-related fungal keratitis in Turkey. We believe, hence, that correction of this misinformation would be beneficial for further studies.

Skin and soft tissue infections caused by methicillin-resistant Staphylococcus aureus (MRSA): an affliction of the underclass.

PubMed

Vayalumkal, Joseph V; Suh, Kathryn N; Toye, Baldwin; Ramotar, Karamchand; Saginur, Raphael; Roth, Virginia R

2012-11-01

The objective of this study was to determine whether skin and soft tissue infections (SSTIs) caused by methicillin-resistant Staphylococcus aureus (MRSA) in patients presenting to The Ottawa Hospital emergency departments (TOHEDs) differed from SSTIs caused by methicillin-susceptible Staphylococcus aureus (MSSA) with regard to risk factors, management, and outcomes. All patients seen at TOHEDs in 2006 and 2007 with SSTIs who yielded MRSA or MSSA in cultures from the site of infection were eligible for inclusion. We excluded patients with decubitus ulcers and infections related to diabetes or peripheral vascular disease. We used an unmatched case-control design. Cases were defined as patients with MRSA isolated from the infection site, and controls were defined as patients with MSSA isolated from the infection site. Data were collected retrospectively from health records and laboratory and hospital information systems. A total of 153 patients were included in the study (81 cases and 72 controls). The mean age of cases was 37 years, compared to 47 years for the controls (p < 0.001). Cases were more likely to have transient residence (31% v. 3% [OR 15.6, 95% CI 3.9-61.8, p < 0.001]), present with abscesses (64% v. 15% [OR 9.9, 95% CI 4.3-23.7, p < .001]), have a documented history of hepatitis C infection (28% v. 3% [OR 13.9, 95% CI 3.9-55.0, p < 0.001]), and have a history of substance abuse (53% v. 10% [OR 10.5, 95% CI 4.4-25.1, p < 0.001]). Cases most commonly used crack cocaine and injection drugs. SSTIs caused by MRSA at TOHEDs mainly occur in a population that is young and transient with comorbidities such as hepatitis C and substance abuse.

Influenza A Virus Infection Damages Zebrafish Skeletal Muscle and Exacerbates Disease in Zebrafish Modeling Duchenne Muscular Dystrophy

PubMed Central

Goody, Michelle; Jurczyszak, Denise; Kim, Carol; Henry, Clarissa

2017-01-01

INTRODUCTION: Both genetic and infectious diseases can result in skeletal muscle degeneration, inflammation, pain, and/or weakness. Duchenne muscular dystrophy (DMD) is the most common congenital muscle disease. DMD causes progressive muscle wasting due to mutations in Dystrophin. Influenza A and B viruses are frequently associated with muscle complications, especially in children. Infections activate an immune response and immunosuppressant drugs reduce DMD symptoms. These data suggest that the immune system may contribute to muscle pathology. However, roles of the immune response in DMD and Influenza muscle complications are not well understood. Zebrafish with dmd mutations are a well-characterized model in which to study the molecular and cellular mechanisms of DMD pathology. We recently showed that zebrafish can be infected by human Influenza A virus (IAV). Thus, the zebrafish is a powerful system with which to ask questions about the etiology and mechanisms of muscle damage due to genetic and/or infectious diseases. METHODS: We infected zebrafish with IAV and assayed muscle tissue structure, sarcolemma integrity, cell-extracellular matrix (ECM) attachment, and molecular and cellular markers of inflammation in response to IAV infection alone or in the context of DMD. RESULTS: We find that IAV-infected zebrafish display mild muscle degeneration with sarcolemma damage and compromised ECM adhesion. An innate immune response is elicited in muscle in IAV-infected zebrafish: NFkB signaling is activated, pro-inflammatory cytokine expression is upregulated, and neutrophils localize to sites of muscle damage. IAV-infected dmd mutants display more severe muscle damage than would be expected from an additive effect of dmd mutation and IAV infection, suggesting that muscle damage caused by Dystrophin-deficiency and IAV infection is synergistic. DISCUSSION: These data demonstrate the importance of preventing IAV infections in individuals with genetic muscle diseases. Elucidating the mechanisms of immune-mediated muscle damage will not only apply to DMD and IAV, but also to other conditions where the immune system, inflammation, and muscle tissue are known to be affected, such as autoimmune diseases, cancer, and aging. PMID:29188128

Influenza A Virus Infection Damages Zebrafish Skeletal Muscle and Exacerbates Disease in Zebrafish Modeling Duchenne Muscular Dystrophy.

PubMed

Goody, Michelle; Jurczyszak, Denise; Kim, Carol; Henry, Clarissa

2017-10-25

Both genetic and infectious diseases can result in skeletal muscle degeneration, inflammation, pain, and/or weakness. Duchenne muscular dystrophy (DMD) is the most common congenital muscle disease. DMD causes progressive muscle wasting due to mutations in Dystrophin. Influenza A and B viruses are frequently associated with muscle complications, especially in children. Infections activate an immune response and immunosuppressant drugs reduce DMD symptoms. These data suggest that the immune system may contribute to muscle pathology. However, roles of the immune response in DMD and Influenza muscle complications are not well understood. Zebrafish with dmd mutations are a well-characterized model in which to study the molecular and cellular mechanisms of DMD pathology. We recently showed that zebrafish can be infected by human Influenza A virus (IAV). Thus, the zebrafish is a powerful system with which to ask questions about the etiology and mechanisms of muscle damage due to genetic and/or infectious diseases. We infected zebrafish with IAV and assayed muscle tissue structure, sarcolemma integrity, cell-extracellular matrix (ECM) attachment, and molecular and cellular markers of inflammation in response to IAV infection alone or in the context of DMD. We find that IAV-infected zebrafish display mild muscle degeneration with sarcolemma damage and compromised ECM adhesion. An innate immune response is elicited in muscle in IAV-infected zebrafish: NFkB signaling is activated, pro-inflammatory cytokine expression is upregulated, and neutrophils localize to sites of muscle damage. IAV-infected dmd mutants display more severe muscle damage than would be expected from an additive effect of dmd mutation and IAV infection, suggesting that muscle damage caused by Dystrophin-deficiency and IAV infection is synergistic. These data demonstrate the importance of preventing IAV infections in individuals with genetic muscle diseases. Elucidating the mechanisms of immune-mediated muscle damage will not only apply to DMD and IAV, but also to other conditions where the immune system, inflammation, and muscle tissue are known to be affected, such as autoimmune diseases, cancer, and aging.

Eosinophilic pustular folliculitis: a sterile folliculitis of unknown cause?

PubMed

Brenner, S; Wolf, R; Ophir, J

1994-08-01

Eosinophilic pustular folliculitis (EPF) was initially defined as a sterile folliculitis of unknown cause. Because attempts to demonstrate bacterial organisms have been unsuccessful, and antibiotic therapy is usually ineffective, a bacterial infection is not considered a plausible causative factor for this disease. Our purpose was to describe five patients with the clinical and histologic characteristics of EPF and to report the results of bacterial cultures. Biopsy specimens were examined and pustules were cultured. In three of the five patients, Pseudomonas infection of the hair follicle was the cause of the disease as proven by repeated cultures and the response to specific therapy. Three patients had a systemic disorder known to cause immunologic alteration: AIDS in one and a myeloproliferative disorder in two. Although EPF was initially defined as a sterile folliculitis of unknown origin, three of our patients had an identifiable and treatable cause. We believe that these cases warrant the diagnosis of EPF.

Leading medical causes of mortality among male prisoners in Texas, 1992--2003.

PubMed

Harzke, Amy J; Baillargeon, Jacques G; Kelley, Michael F; Pruitt, Sandi L; Pulvino, John S; Paar, David P

2011-07-01

Data from the Texas prison system and the Texas Vital Statistics Bureau were used to identify and assess the leading medical causes of death from 1992 to 2003 among male prisoners in Texas (N = 4,026). The leading medical causes of death were infection, cancer, cardiovascular disease (CVD), liver disease, and respiratory disease. Of these, only cancer showed a significant average annual increase in crude death rates (2.5% [0.2% to 4.9%]). Among prisoners aged 55 to 84 years, crude average annual death rates due to cancer and CVD were high and substantially exceeded death rates due to other causes. Among prisoners aged 25 to 44 years, crude average annual death rates due to infection exceeded death rates due to other causes. Continued improvements in the prevention, screening, and treatment of these conditions are warranted in correctional health care settings.

Emerging and Reemerging Neurologic Infections

PubMed Central

Glaser, Carol A.

2014-01-01

The list of emerging and reemerging pathogens that cause neurologic disease is expanding. Various factors, including population growth and a rise in international travel, have contributed to the spread of pathogens to previously nonendemic regions. Recent advances in diagnostic methods have led to the identification of novel pathogens responsible for infections of the central nervous system. Furthermore, new issues have arisen surrounding established infections, particularly in an increasingly immunocompromised population due to advances in the treatment of rheumatologic disease and in transplant medicine. PMID:25360203

The Immunologic Basis for Severe Neonatal Herpes Disease and Potential Strategies for Therapeutic Intervention

PubMed Central

Gantt, Soren; Muller, William J.

2013-01-01

Herpes simplex viruses types 1 and 2 (HSV-1 and HSV-2) infect a large proportion of the world's population. Infection is life-long and can cause periodic mucocutaneous symptoms, but it only rarely causes life-threatening disease among immunocompetent children and adults. However, when HSV infection occurs during the neonatal period, viral replication is poorly controlled and a large proportion of infants die or develop disability even with optimal antiviral therapy. Increasingly, specific differences are being elucidated between the immune system of newborns and those of older children and adults, which predispose to severe infections and reflect the transition from fetal to postnatal life. Studies in healthy individuals of different ages, individuals with primary or acquired immunodeficiencies, and animal models have contributed to our understanding of the mechanisms that control HSV infection and how these may be impaired during the neonatal period. This paper outlines our current understanding of innate and adaptive immunity to HSV infection, immunologic differences in early infancy that may account for the manifestations of neonatal HSV infection, and the potential of interventions to augment neonatal immune protection against HSV disease. PMID:23606868

Deleterious Wolbachia in the ant Formica truncorum.

PubMed

Wenseleers, T; Sundström, L; Billen, J

2002-03-22

Wolbachia is a maternally inherited bacterium that may manipulate the reproduction of its arthropod hosts. In insects, it is known to lead to inviable matings, cause asexual reproduction or kill male offspring, all to its own benefit, but to the detriment of its host. In social Hymenoptera, Wolbachia occurs widely, but little is known about its fitness effects. We report on a Wolbachia infection in the wood ant Formica truncorum, and evaluate whether it influences reproductive patterns. All 33 colonies of the study population were infected, suggesting that Wolbachia infection is at, or close to, fixation. Interestingly, in colonies with fewer infected workers, significantly more sexuals are produced, indicating that Wolbachia has deleterious effects in this species. In addition, adult workers are shown to have significantly lower infection rates (45%) than worker pupae (87%) or virgin queens (94%), suggesting that workers lose their infection over life. Clearance of Wolbachia infection has, to our knowledge, never been shown in any other natural system, but we argue that it may, in this case, represent an adaptive strategy to reduce colony load. The cause of fixation requires further study, but our data strongly suggest that Wolbachia has no influence on the sex ratio in this species.

Co-trimoxazole

MedlinePlus

... cannot digest the nutrients needed for good health); human immunodeficiency virus (HIV) infection; porphyria (an inherited blood disease that may cause skin or nervous system problems); thyroid disease; or glucose-6-phosphate dehydrogenase ( ...

Case Report: Protothecal Tenosynovitis

PubMed Central

Lee, Jin Seo; Moon, Goo Hyun; Lee, Nam Yong

2008-01-01

Protothecosis is a rare infection caused by achlorophyllic algae called Prototheca. Approximately 117 cases have been described in the literature world wide, the majority caused by the species P. wickerhamii. Cutaneous infection is the most common and cases of tenosynovitis are very rare. A local or systemic immunosuppressive factor is seen in half of the cases of protothecosis. We report a case of protothecal tenosynovitis in a middle-aged, immunocompetent woman that developed after she received sclerosing therapy of varicose veins. Administration of itraconazole with surgical débridement produced a good response. We also review the published cases of protothecal tenosynovitis. PMID:18791778

Case report: protothecal tenosynovitis.

PubMed

Lee, Jin Seo; Moon, Goo Hyun; Lee, Nam Yong; Peck, Kyong Ran

2008-12-01

Protothecosis is a rare infection caused by achlorophyllic algae called Prototheca. Approximately 117 cases have been described in the literature world wide, the majority caused by the species P. wickerhamii. Cutaneous infection is the most common and cases of tenosynovitis are very rare. A local or systemic immunosuppressive factor is seen in half of the cases of protothecosis. We report a case of protothecal tenosynovitis in a middle-aged, immunocompetent woman that developed after she received sclerosing therapy of varicose veins. Administration of itraconazole with surgical débridement produced a good response. We also review the published cases of protothecal tenosynovitis.

Direct maldi-tof mass spectrometry assay of blood culture broths for rapid identification of Candida species causing bloodstream infections: an observational study in two large microbiology laboratories.

PubMed

Spanu, Teresa; Posteraro, Brunella; Fiori, Barbara; D'Inzeo, Tiziana; Campoli, Serena; Ruggeri, Alberto; Tumbarello, Mario; Canu, Giulia; Trecarichi, Enrico Maria; Parisi, Gabriella; Tronci, Mirella; Sanguinetti, Maurizio; Fadda, Giovanni

2012-01-01

We evaluated the reliability of the Bruker Daltonik's MALDI Biotyper system in species-level identification of yeasts directly from blood culture bottles. Identification results were concordant with those of the conventional culture-based method for 95.9% of Candida albicans (187/195) and 86.5% of non-albicans Candida species (128/148). Results were available in 30 min (median), suggesting that this approach is a reliable, time-saving tool for routine identification of Candida species causing bloodstream infection.

Antibacterial photodynamic therapy with 808-nm laser and indocyanine green on abrasion wound models

NASA Astrophysics Data System (ADS)

Topaloglu, Nermin; Güney, Melike; Yuksel, Sahru; Gülsoy, Murat

2015-02-01

Infections with pathogens could cause serious health problems, such as septicemia and subsequent death. Some of these deaths are caused by nosocomial, chronic, or burn-related wound infections. Photodynamic therapy (PDT) can be useful for the treatment of these infections. Our aim was to investigate the antibacterial effect of indocyanine green (ICG) and 808-nm laser on a rat abrasion wound model infected with the multidrug resistant Staphylococcus aureus strain. Abrasion wounds were infected with a multidrug resistant clinical isolate of S. aureus. ICG concentrations of 500, 1000, and 2000 μg/ml were applied with a 450 J/cm2 energy dose. Temperature change was monitored by a thermocouple system. The remaining bacterial burden was determined by the serial dilution method after each application. Wounds were observed for 11 days posttreatment. The recovery process was assessed macroscopically. Tissue samples were also examined histologically by hematoxylin-eosin staining. Around a 90% reduction in bacterial burden was observed after PDT applications. In positive control groups (ICG-only and laser-only groups), there was no significant reduction. The applied energy dose did not cause any thermal damage to the target tissue or host environment. Results showed that ICG together with a 808-nm laser might be a promising antibacterial method to eliminate infections in animals and accelerate the wound-healing process.

Genomic and pathogenic analysis of a Muscovy duck parvovirus strain causing short beak and dwarfism syndrome without tongue protrusion.

PubMed

Fu, Qiuling; Huang, Yu; Wan, Chunhe; Fu, Guanghua; Qi, Baomin; Cheng, Longfei; Shi, Shaohua; Chen, Hongmei; Liu, Rongchang; Chen, Zhenhai

2017-12-01

In 2008, clinical cases of short beak and dwarfism syndrome (SBDS) caused by Muscovy duck parvovirus (MDPV) infection were found in mule duck and Taiwan white duck farms in Fujian, China. A MDPV LH strain causing duck SBDS without tongue protrusion was isolated in this study. Phylogenetic analysis show that the MDPV LH strain was clustered together with other MDPV strains, but divergent from GPV isolates. Two major fragment deletions were found in the inverted terminal repeats (ITR) of MDPV LH similar to the ones in the ITR of MDPV GX5, YY and SAAS-SHNH strains. To investigate the pathogenicity of the MDPV LH strain, virus infection of young mule ducks was performed. The infected ducks showed SBDS symptoms including retard growth and shorten beaks without tongue protrusion. Atrophy of thymus, spleen and bursa of Fabricius was identified in the infected ducks. The results show that MDPV LH strain is moderately pathogenic to mule duck, leading to occurrence of SBDS. As far as we know, it is the first study showing that SBDS without tongue protrusion, and atrophy of thymus, spleen and bursa of Fabricius possibly associated with immunosuppression were found in the MDPV-infected ducks. The established duck-MDPV-SBDS system will help us to further work on the virus pathogenesis and develop efficacious vaccine against MDPV infection. Copyright © 2017. Published by Elsevier Ltd.

Puerperal group A streptococcal infection: beyond Semmelweis.

PubMed

Anderson, Brenna L

2014-04-01

Ignaz Semmelweiss made one of the most important contributions to modern medicine when he instituted handwashing in an obstetric clinic in Austria in 1847, decreasing mortality there from more than 10% to 2%. Unfortunately, puerperal sepsis remains a leading cause of maternal mortality throughout the world. Group A streptococcus (GAS), Streptococcus pyogenes, is an organism associated with high rates of morbidity and mortality from puerperal infections. When associated with sepsis, known as streptococcal toxic shock syndrome, mortality rates approach 30-50%. Group A streptococcus can cause invasive infections in the form of endometritis, necrotizing fasciitis, or streptococcal toxic shock syndrome. The clinical presentation of women with puerperal GAS infections is often atypical with extremes of temperature, unusual and vague pain, and pain in extremities. Toxin production by the organism may allow GAS to spread across tissue planes and cause necrosis while evading containment by the maternal immune system in the form of a discrete abscess. Endometrial aspiration in addition to blood cultures may be a useful rapid diagnostic tool. Imaging may appear normal and should not dissuade the clinician from aggressive management. When suspected, invasive GAS infections should be treated emergently with fluid resuscitation, antibiotic administration, and source control. The optimal antibiotic regimen contains penicillin and clindamycin. Source control may require extensive wound or vulvar debridement, hysterectomy, or a combination of these, which may be life-saving. The benefit of immunoglobulins in management of puerperal GAS infections is unclear.

Anaemia, iron deficiency and susceptibility to infections.

PubMed

Jonker, Femke A M; Boele van Hensbroek, Michaël

2014-11-01

Anaemia, iron deficiency and infections are three major causes of childhood morbidity and mortality throughout the world, although they predominantly occur in resource limited settings. As the three conditions may have the same underlying aetiologies, they often occur simultaneously and may interact. Being an essential component in erythropoiesis, iron is also essential for proper functioning of the host immune system as well as an essential nutrient for growth of various pathogens, including non-typhoid salmonella. This has resulted in a treatment dilemma in which iron is needed to treat the iron deficient anaemia and improve the immune system of the host (child), but the same treatment may also put the child at an increased, potentially fatal, infection risk. Copyright © 2014 The British Infection Association. Published by Elsevier Ltd. All rights reserved.

Getting rid of athlete's foot.

PubMed

2002-07-01

At any one time, around 17% of adults in the UK have athlete's foot. While such fungal infection is not usually dangerous, it can cause discomfort, may be resistant to treatment, and may spread to other parts of the body or to other people. Affected feet can also become secondarily infected by bacteria. Here, we review the topical and systemic treatment of athlete's foot.

Inheritance of the bark reaction resistance mechanism in Pinus monticola infected by Cronartium ribicola

Treesearch

Ray J. Hoff

1986-01-01

Necrotic reactions in branch or main stems of western white pine (Pinus monticola Dougl.) caused by infection by the blister rust fungus (Cronartium ribicola J. C. Fisch. ex Rabenh.) are a major mechanism of resistance. Overall, 26 percent of the seedlings eliminated the fungus via this defense system. Heritability based upon crossing family groups averaged 33 percent...

Lymphocytic choriomeningitis virus (LCMV) infection of macaques: a model for Lassa fever

PubMed Central

Zapata, Juan C.; Pauza, C. David; Djavani, Mahmoud M.; Rodas, Juan D.; Moshkoff, Dmitry; Bryant, Joseph; Ateh, Eugene; Garcia, Cybele; Lukashevich, Igor S.; Salvato, Maria S.

2011-01-01

Arenaviruses such as Lassa fever virus (LASV) and lymphocytic choriomeningitis virus (LCMV) are benign in their natural reservoir hosts, and can occasionally cause severe viral hemorrhagic fever (VHF) in non-human primates and in human beings. LCMV is considerably more benign for human beings than Lassa virus, however certain strains, like the LCMV-WE strain, can cause severe disease when the virus is delivered as a high-dose inoculum. Here we describe a rhesus macaque model for Lassa fever that employs a virulent strain of LCMV. Since LASV must be studied within Biosafety Level-4 (BSL-4) facilities, the LCMV-infected macaque model has the advantage that it can be used at BSL-3. LCMV-induced disease is rarely as severe as other VHF, but it is similar in cases where vascular leakage leads to lethal systemic failure. The LCMV-infected macaque has been valuable for describing the course of disease with differing viral strains, doses and routes of infection. By monitoring system-wide changes in physiology and gene expression in a controlled experimental setting, it is possible to identify events that are pathognomonic for developing VHF and potential treatment targets. PMID:21820469

Dissemination of Persistent Intestinal Bacteria via the Mesenteric Lymph Nodes Causes Typhoid Relapse▿

PubMed Central

Griffin, Amanda J.; Li, Lin-Xi; Voedisch, Sabrina; Pabst, Oliver; McSorley, Stephen J.

2011-01-01

Enteric pathogens can cause relapsing infections in a proportion of treated patients, but greater understanding of this phenomenon is hindered by the lack of appropriate animal models. We report here a robust animal model of relapsing primary typhoid that initiates after apparently successful antibiotic treatment of susceptible mice. Four days of enrofloxacin treatment were sufficient to reduce bacterial loads below detectable levels in all major organs, and mice appeared otherwise healthy. However, any interruption of further antibiotic therapy allowed renewed fecal shedding and renewed bacterial growth in systemic tissues to occur, and mice eventually succumbed to relapsing infection. In vivo imaging of luminescent Salmonella identified the mesenteric lymph nodes (MLNs) as a major reservoir of relapsing infection. A magnetic-bead enrichment strategy isolated MLN-resident CD11b+ Gr-1− monocytes associated with low numbers of persistent Salmonella. However, the removal of MLNs increased the severity of typhoid relapse, demonstrating that this organ serves as a protective filter to restrain the dissemination of bacteria during antibiotic therapy. Together, these data describe a robust animal model of typhoid relapse and identify an important intestinal phagocyte subset involved in protection against the systemic spread of enteric infection. PMID:21263018

Herpes simplex virus-1 evasion of CD8+ T cell accumulation contributes to viral encephalitis.

PubMed

Koyanagi, Naoto; Imai, Takahiko; Shindo, Keiko; Sato, Ayuko; Fujii, Wataru; Ichinohe, Takeshi; Takemura, Naoki; Kakuta, Shigeru; Uematsu, Satoshi; Kiyono, Hiroshi; Maruzuru, Yuhei; Arii, Jun; Kato, Akihisa; Kawaguchi, Yasushi

2017-10-02

Herpes simplex virus-1 (HSV-1) is the most common cause of sporadic viral encephalitis, which can be lethal or result in severe neurological defects even with antiviral therapy. While HSV-1 causes encephalitis in spite of HSV-1-specific humoral and cellular immunity, the mechanism by which HSV-1 evades the immune system in the central nervous system (CNS) remains unknown. Here we describe a strategy by which HSV-1 avoids immune targeting in the CNS. The HSV-1 UL13 kinase promotes evasion of HSV-1-specific CD8+ T cell accumulation in infection sites by downregulating expression of the CD8+ T cell attractant chemokine CXCL9 in the CNS of infected mice, leading to increased HSV-1 mortality due to encephalitis. Direct injection of CXCL9 into the CNS infection site enhanced HSV-1-specific CD8+ T cell accumulation, leading to marked improvements in the survival of infected mice. This previously uncharacterized strategy for HSV-1 evasion of CD8+ T cell accumulation in the CNS has important implications for understanding the pathogenesis and clinical treatment of HSV-1 encephalitis.

Measles Virus Host Invasion and Pathogenesis.

PubMed

Laksono, Brigitta M; de Vries, Rory D; McQuaid, Stephen; Duprex, W Paul; de Swart, Rik L

2016-07-28

Measles virus is a highly contagious negative strand RNA virus that is transmitted via the respiratory route and causes systemic disease in previously unexposed humans and non-human primates. Measles is characterised by fever and skin rash and usually associated with cough, coryza and conjunctivitis. A hallmark of measles is the transient immune suppression, leading to increased susceptibility to opportunistic infections. At the same time, the disease is paradoxically associated with induction of a robust virus-specific immune response, resulting in lifelong immunity to measles. Identification of CD150 and nectin-4 as cellular receptors for measles virus has led to new perspectives on tropism and pathogenesis. In vivo studies in non-human primates have shown that the virus initially infects CD150⁺ lymphocytes and dendritic cells, both in circulation and in lymphoid tissues, followed by virus transmission to nectin-4 expressing epithelial cells. The abilities of the virus to cause systemic infection, to transmit to numerous new hosts via droplets or aerosols and to suppress the host immune response for several months or even years after infection make measles a remarkable disease. This review briefly highlights current topics in studies of measles virus host invasion and pathogenesis.

Plasma bacterial and mitochondrial DNA distinguish bacterial sepsis from sterile systemic inflammatory response syndrome and quantify inflammatory tissue injury in nonhuman primates.

PubMed

Sursal, Tolga; Stearns-Kurosawa, Deborah J; Itagaki, Kiyoshi; Oh, Sun-Young; Sun, Shiqin; Kurosawa, Shinichiro; Hauser, Carl J

2013-01-01

Systemic inflammatory response syndrome (SIRS) is a fundamental host response common to bacterial infection and sterile tissue injury. Systemic inflammatory response syndrome can cause organ dysfunction and death, but its mechanisms are incompletely understood. Moreover, SIRS can progress to organ failure or death despite being sterile or after control of the inciting infection. Biomarkers discriminating between sepsis, sterile SIRS, and postinfective SIRS would therefore help direct care. Circulating mitochondrial DNA (mtDNA) is a damage-associated molecular pattern reflecting cellular injury. Circulating bacterial 16S DNA (bDNA) is a pathogen-associated pattern (PAMP) reflecting ongoing infection. We developed quantitative polymerase chain reaction assays to quantify these markers, and predicting their plasma levels might help distinguish sterile injury from infection. To study these events in primates, we assayed banked serum from Papio baboons that had undergone a brief challenge of intravenous Bacillus anthracis delta Sterne (modified to remove toxins) followed by antibiotics (anthrax) that causes organ failure and death. To investigate the progression of sepsis to "severe" sepsis and death, we studied animals where anthrax was pretreated with drotrecogin alfa (activated protein C), which attenuates sepsis in baboons. We also contrasted lethal anthrax bacteremia against nonlethal E. coli bacteremia and against sterile tissue injury from Shiga-like toxin 1. Bacterial DNA and mtDNA levels in timed samples were correlated with blood culture results and assays of organ function. Sterile injury by Shiga-like toxin 1 increased mtDNA, but bDNA was undetectable: consistent with the absence of infection. The bacterial challenges caused parallel early bDNA and mtDNA increases, but bDNA detected pathogens even after bacteria were undetectable by culture. Sublethal E. coli challenge only caused transient rises in mtDNA consistent with a self-limited injury. In lethal anthrax challenge (n = 4), bDNA increased transiently, but mtDNA levels remained elevated until death, consistent with persistent septic tissue damage after bacterial clearance. Critically, activated protein C pretreatment (n = 4) allowed mtDNA levels to decay after bacterial clearance with sparing of organ function and survival. In summary, host tissue injury correlates with mtDNA whether infective or sterile. Mitochondrial DNA and bDNA polymerase chain reactions can quantify tissue injury incurred by septic or sterile mechanisms and suggest the source of SIRS of unknown origin.

Fluorescence diagnosis of upper respiratory tract infections

NASA Astrophysics Data System (ADS)

Blanco, Kate C.; Inada, Natalia M.; Kurachi, Cristina; Bagnato, Vanderlei S.

2015-06-01

The pharyngitis and laryngitis are respiratory tract infections highly common. Pharyngitis can be accompanied by fever, especially if caused by a systemic infection. Laryngitis is an inflammation of your voice box (larynx) from irritation or infection. The conventional treatment is the antibiotics administration, which may be responsible by an increase of identification of bacterial strains resistant to drug. This fact associated to high incidence of these infections become important to develop new technologies for diagnosis. This study aims to evaluate the use of widefield fluorescence imaging for the characterization of oropharynx infections, in order to diagnose the bacteria colonization. The imaging system for wide field fluorescence visualization is Evince® (MMOptics, São Carlos, SP, Brazil) coupled to an Apple iPhone® cell phone device. The system consists of Light Emitting Diodes (LEDs) operating in the violet blue region centered at green-red spectrum 450 nm and optical filters that allow viewing of fluorescence. A tongue depressor was adapted to Evince® for mouth opening. The same images were captured with white light and fluorescence with an optical system. The red fluorescence may be a bacterial marker for physiological monitoring of oropharynx infection processes. The bacterial biofilm on tissue were assigned to the presence of protoporphyrin IX. This work indicates that the autofluorescence of the tissue may be used as a non-invasive technique to aid in the oropharynx infection diagnostic.

A link between perianal strep and pediatric autoimmune neuropsychiatric disorder associated with streptococcal infection (PANDAS).

PubMed

Toufexis, Megan; Deoleo, Caroline; Elia, Josephine; Murphy, Tanya K

2014-04-01

Perianal streptococcal dermatitis is an infection caused by group A streptococcus (GAS). Children with a pediatric autoimmune neuropsychiatric disorder associated with streptococcal infections (PANDAS) phenotype may have tics or obsessive compulsive symptoms secondary to a systemic immune activation by GAS infecting perianal areas. In this retrospective case series, the authors describe three children with symptoms consistent with PANDAS and a confirmed perianal streptococcal dermatitis as the likely infectious trigger. Concomitant perianal dermatitis and new-onset obsessive-compulsive symptoms and/or tics are strong indications for perianal culture and rapid antigen detection test in young children.

Biology of flower-infecting fungi.

PubMed

Ngugi, Henry K; Scherm, Harald

2006-01-01

The ability to infect host flowers offers important ecological benefits to plant-parasitic fungi; not surprisingly, therefore, numerous fungal species from a wide range of taxonomic groups have adopted a life style that involves flower infection. Although flower-infecting fungi are very diverse, they can be classified readily into three major groups: opportunistic, unspecialized pathogens causing necrotic symptoms such as blossom blights (group 1), and specialist flower pathogens which infect inflorescences either through the gynoecium (group 2) or systemically through the apical meristem (group 3). This three-tier system is supported by life history attributes such as host range, mode of spore transmission, degree of host sterilization as a result of infection, and whether or not the fungus undergoes an obligate sexual cycle, produces resting spores in affected inflorescences, and is r- or K-selected. Across the three groups, the flower as an infection court poses important challenges for disease management. Ecologically and evolutionarily, terms and concepts borrowed from the study of venereal (sexually transmitted) diseases of animals do not adequately capture the range of strategies employed by fungi that infect flowers.

Secular Trends in Infection-Related Mortality after Kidney Transplantation.

PubMed

Kinnunen, Susanna; Karhapää, Pauli; Juutilainen, Auni; Finne, Patrik; Helanterä, Ilkka

2018-05-07

Infections are the most common noncardiovascular causes of death after kidney transplantation. We analyzed the current infection-related mortality among kidney transplant recipients in a nationwide cohort in Finland. Altogether, 3249 adult recipients of a first kidney transplant from 1990 to 2012 were included. Infectious causes of death were analyzed, and the mortality rates for infections were compared between two eras (1990-1999 and 2000-2012). Risk factors for infectious deaths were analyzed with Cox regression and competing risk analyses. Altogether, 953 patients (29%) died during the follow-up, with 204 infection-related deaths. Mortality rate (per 1000 patient-years) due to infections was lower in the more recent cohort (4.6; 95% confidence interval, 3.5 to 6.1) compared with the older cohort (9.1; 95% confidence interval, 7.6 to 10.7); the incidence rate ratio of infectious mortality was 0.51 (95% confidence interval, 0.30 to 0.68). The main causes of infectious deaths were common bacterial infections: septicemia in 38% and pulmonary infections in 45%. Viral and fungal infections caused only 2% and 3% of infectious deaths, respectively (such as individual patients with Cytomegalovirus pneumonia, Herpes simplex virus meningoencephalitis, Varicella zoster virus encephalitis, and Pneumocystis jirovecii infection). Similarly, opportunistic bacterial infections rarely caused death; only one death was caused by Listeria monocytogenes , and two were caused by Mycobacterium tuberculosis . Only 23 (11%) of infection-related deaths occurred during the first post-transplant year. Older recipient age, higher plasma creatinine concentration at the end of the first post-transplant year, diabetes as a cause of ESKD, longer pretransplant dialysis duration, acute rejection, low albumin level, and earlier era of transplantation were associated with increased risk of infectious death in multivariable analysis. The risk of death due to infectious causes after kidney transplantation in Finland dropped by one half since the 1990s. Common bacterial infections remained the most frequent cause of infection-related mortality, whereas opportunistic viral, fungal, or unconventional bacterial infections rarely caused deaths after kidney transplantation. Copyright © 2018 by the American Society of Nephrology.

Altered development of the brain after focal herpesvirus infection of the central nervous system.

PubMed

Koontz, Thad; Bralic, Marina; Tomac, Jelena; Pernjak-Pugel, Ester; Bantug, Glen; Jonjic, Stipan; Britt, William J

2008-02-18

Human cytomegalovirus infection of the developing central nervous system (CNS) is a major cause of neurological damage in newborn infants and children. To investigate the pathogenesis of this human infection, we developed a mouse model of infection in the developing CNS. Intraperitoneal inoculation of newborn animals with murine cytomegalovirus resulted in virus replication in the liver followed by virus spread to the brain. Virus infection of the CNS was associated with the induction of inflammatory responses, including the induction of a large number of interferon-stimulated genes and histological evidence of focal encephalitis with recruitment of mononuclear cells to foci containing virus-infected cells. The morphogenesis of the cerebellum was delayed in infected animals. The defects in cerebellar development in infected animals were generalized and, although correlated temporally with virus replication and CNS inflammation, spatially unrelated to foci of virus-infected cells. Specific defects included decreased granular neuron proliferation and migration, expression of differentiation markers, and activation of neurotrophin receptors. These findings suggested that in the developing CNS, focal virus infection and induction of inflammatory responses in resident and infiltrating mononuclear cells resulted in delayed cerebellar morphogenesis.

Altered development of the brain after focal herpesvirus infection of the central nervous system

PubMed Central

Koontz, Thad; Bralic, Marina; Tomac, Jelena; Pernjak-Pugel, Ester; Bantug, Glen; Jonjic, Stipan; Britt, William J.

2008-01-01

Human cytomegalovirus infection of the developing central nervous system (CNS) is a major cause of neurological damage in newborn infants and children. To investigate the pathogenesis of this human infection, we developed a mouse model of infection in the developing CNS. Intraperitoneal inoculation of newborn animals with murine cytomegalovirus resulted in virus replication in the liver followed by virus spread to the brain. Virus infection of the CNS was associated with the induction of inflammatory responses, including the induction of a large number of interferon-stimulated genes and histological evidence of focal encephalitis with recruitment of mononuclear cells to foci containing virus-infected cells. The morphogenesis of the cerebellum was delayed in infected animals. The defects in cerebellar development in infected animals were generalized and, although correlated temporally with virus replication and CNS inflammation, spatially unrelated to foci of virus-infected cells. Specific defects included decreased granular neuron proliferation and migration, expression of differentiation markers, and activation of neurotrophin receptors. These findings suggested that in the developing CNS, focal virus infection and induction of inflammatory responses in resident and infiltrating mononuclear cells resulted in delayed cerebellar morphogenesis. PMID:18268036

Clinical and Pathophysiological Overview of Acinetobacter Infections: a Century of Challenges

PubMed Central

Nielsen, Travis B.; Bonomo, Robert A.; Pantapalangkoor, Paul; Luna, Brian; Spellberg, Brad

2016-01-01

SUMMARY Acinetobacter is a complex genus, and historically, there has been confusion about the existence of multiple species. The species commonly cause nosocomial infections, predominantly aspiration pneumonia and catheter-associated bacteremia, but can also cause soft tissue and urinary tract infections. Community-acquired infections by Acinetobacter spp. are increasingly reported. Transmission of Acinetobacter and subsequent disease is facilitated by the organism's environmental tenacity, resistance to desiccation, and evasion of host immunity. The virulence properties demonstrated by Acinetobacter spp. primarily stem from evasion of rapid clearance by the innate immune system, effectively enabling high bacterial density that triggers lipopolysaccharide (LPS)–Toll-like receptor 4 (TLR4)-mediated sepsis. Capsular polysaccharide is a critical virulence factor that enables immune evasion, while LPS triggers septic shock. However, the primary driver of clinical outcome is antibiotic resistance. Administration of initially effective therapy is key to improving survival, reducing 30-day mortality threefold. Regrettably, due to the high frequency of this organism having an extreme drug resistance (XDR) phenotype, early initiation of effective therapy is a major clinical challenge. Given its high rate of antibiotic resistance and abysmal outcomes (up to 70% mortality rate from infections caused by XDR strains in some case series), new preventative and therapeutic options for Acinetobacter spp. are desperately needed. PMID:27974412

Can Helicobacter pylori infection influence human reproduction?

PubMed

Moretti, Elena; Figura, Natale; Collodel, Giulia; Ponzetto, Antonio

2014-05-21

Helicobacter pylori (H. pylori) infection could be associated with extra-digestive diseases. Here, we report the evidences concerning the decrease in reproductive potential occurring in individuals infected by H. pylori, especially by strains expressing CagA. This infection is more prevalent in individuals with fertility disorders. Infected women have anti-H. pylori antibodies in cervical mucus and follicular fluid that may decrease sperm motility and cross react immunologically with spermatozoa, conceivably hampering the oocyte/sperm fusion. Infection by CagA positive organisms enhances the risk of preeclampsia, which is a main cause of foetus death. These findings are supported by the results of experimental infections of pregnant mice, which may cause reabsorption of a high number of foetuses and alter the balance between Th1 and Th2 cell response. Infected men have decreased sperm motility, viability and numbers of normally shaped sperm and augmented systemic levels of inflammatory cytokines, such as tumor necrosis factor-α, which may damage spermatozoa. In countries where parasitic infestation is endemic, detrimental effects of infection upon spermatozoa may not occur, because the immune response to parasites could determine a switch from a predominant Th1 type to Th2 type lymphocytes, with production of anti-inflammatory cytokines. In conclusion, the evidences gathered until now should be taken into consideration for future studies aiming to explore the possible role of H. pylori infection on human reproduction.

[An adult case of haemophilus parainfluenzae bacteremia and meningitis].

PubMed

Kangas, Ida

2010-01-04

A case of bacteremia and meningitis caused by Haemophilus parainfluenzae in an adult patient without known immunodeficiency and normal complement system is presented. H. parainfluenzae has not previously been reported as the cause of meningitis in Denmark. Patients with invasive H. parainfluenzae infection should be examined for complement factor 7 defect.

Whole genome sequencing and analysis of Campylobacter coli YH502 from retail chicken reveals a plasmid-borne type VI secretion system

USDA-ARS?s Scientific Manuscript database

Campylobacter is a major cause of foodborne illnesses worldwide. Campylobacter infections, commonly caused by ingestion of undercooked poultry and meat products, can lead to gastroenteritis and chronic reactive arthritis in humans. Whole genome sequencing (WGS) is a powerful technology that provides...

Virulence and draft genome sequence overview of multiple strains of the swine pathogen Haemophilus parasuis

USDA-ARS?s Scientific Manuscript database

Haemophilus parasuis is the cause of Glässer’s disease in swine, which is characterized by systemic infection resulting in polyserositis, meningitis, and arthritis. Characterization of this animal disease is complicated by the enormous differences in the severity of disease caused by H. parasuis str...

A Hepatozoon species genetically distinct from H. canis infecting spotted hyenas in the Serengeti ecosystem, Tanzania.

PubMed

East, Marion L; Wibbelt, Gudrun; Lieckfeldt, Dietmar; Ludwig, Arne; Goller, Katja; Wilhelm, Kerstin; Schares, Gereon; Thierer, Dagmar; Hofer, Heribert

2008-01-01

Health monitoring of spotted hyenas (Crocuta crocuta) in the Serengeti ecosystem, Tanzania, revealed Hepatozoon infection in all of 11 immature individuals examined following death from natural causes. Hepatozoon infection was probably an important factor contributing to mortality in two cases that exhibited clinical signs of ataxia, lethargy, ocular discharge, retching, and labored breathing before death. Whether Hepatozoon infection contributed to six deaths from fire, probable lion predation and unknown causes could not be determined. Four deaths from infanticide and starvation were unlikely to be associated with Hepatozoon infection. Histologic examination revealed lung tissue infected with cyst-like structures containing protozoan stages in all eight cases examined and interstitial pneumonia in most cases. Systemic spread of infection to several organs was found in three cases. Alignment of a 426 bp sequence from the parasite's 18s rRNA gene revealed a Hepatozoon species identical to that recently described from two domestic cats in Spain and only 7 bp substitutions when a 853 bp sequence was aligned to this cat Hepatozoon species. Previous reports of infection of wild carnivores in eastern and southern Africa with an unspecified Hepatozoon species similar in appearance to H. canis may have involved the species described in this study.

Postmortem findings and opportunistic infections in HIV-positive patients from a public hospital in Peru

PubMed Central

Eza, Dominique; Cerrillo, Gustavo; Moore, David A.J.; Castro, Cecilia; Ticona, Eduardo; Morales, Domingo; Cabanillas, Jose; Barrantes, Fernando; Alfaro, Alejandro; Benavides, Alejandro; Rafael, Arturo; Valladares, Gilberto; Arevalo, Fernando; Evans, Carlton A.; Gilman, Robert H.

2010-01-01

There is a paucity of HIV autopsy data from South America and none that document the postmortem findings in patients with HIV/AIDS in Peru. The purpose of this autopsy study was to determine the spectrum of opportunistic infections and the causes of mortality in HIV-positive patients at a public hospital in Lima. Clinico-epidemiological information regarding HIV infection in Peru is also reviewed. Sixteen HIV-related hospital postmortems, performed between 1999 and 2004, were included in this retrospective analysis. The primary cause of death was established in 12 patients: one died of neoplasia and 11 of infectious diseases, including 3 from pulmonary infection, 7 from disseminated infection, and 2 from central nervous system infection (one case had dual pathology). Opportunistic infections were identified in 14 cases, comprising cytomegalovirus, histoplasmosis, cryptococcosis, toxoplasmosis, Pneumocystis pneumonia, aspergillosis, tuberculosis, varicella zoster virus, and cryptosporidiosis. Fourteen patients had at least one AIDS-related disease that had been neither clinically suspected nor diagnosed premortem. Moreover, 82% of the diagnoses considered to be of important clinical significance had not been suspected antemortem. The spectrum and frequency of certain opportunistic infections differed from other South American autopsy studies, highlighting the importance of performing HIV/AIDS postmortems in resource-limited countries where locally specific disease patterns may be observed. PMID:16979302

Postmortem findings and opportunistic infections in HIV-positive patients from a public hospital in Peru.

PubMed

Eza, Dominique; Cerrillo, Gustavo; Moore, David A J; Castro, Cecilia; Ticona, Eduardo; Morales, Domingo; Cabanillas, Jose; Barrantes, Fernando; Alfaro, Alejandro; Benavides, Alejandro; Rafael, Arturo; Valladares, Gilberto; Arevalo, Fernando; Evans, Carlton A; Gilman, Robert H

2006-01-01

There is a paucity of HIV autopsy data from South America and none that document the postmortem findings in patients with HIV/AIDS in Peru. The purpose of this autopsy study was to determine the spectrum of opportunistic infections and the causes of mortality in HIV-positive patients at a public hospital in Lima. Clinico-epidemiological information regarding HIV infection in Peru is also reviewed. Sixteen HIV-related hospital postmortems, performed between 1999 and 2004, were included in this retrospective analysis. The primary cause of death was established in 12 patients: one died of neoplasia and 11 of infectious diseases, including 3 from pulmonary infection, 7 from disseminated infection, and 2 from central nervous system infection (one case had dual pathology). Opportunistic infections were identified in 14 cases, comprising cytomegalovirus, histoplasmosis, cryptococcosis, toxoplasmosis, Pneumocystis pneumonia, aspergillosis, tuberculosis, varicella zoster virus, and cryptosporidiosis. Fourteen patients had at least one AIDS-related disease that had been neither clinically suspected nor diagnosed premortem. Moreover, 82% of the diagnoses considered to be of important clinical significance had not been suspected antemortem. The spectrum and frequency of certain opportunistic infections differed from other South American autopsy studies, highlighting the importance of performing HIV/AIDS postmortems in resource-limited countries where locally specific disease patterns may be observed.

Bystander CD4+ T lymphocytes survive in HIV-infected human lymphoid tissue

NASA Technical Reports Server (NTRS)

Grivel, Jean-Charles; Biancotto, Angelique; Ito, Yoshinori; Lima, Rosangela G.; Margolis, Leonid B.

2003-01-01

HIV infection is associated with depletion of CD4(+) T cells. The mechanisms of this phenomenon remain to be understood. In particular, it remains controversial whether and to what extent uninfected ("bystander") CD4(+) T cells die in HIV-infected individuals. We address this question using a system of human lymphoid tissue ex vivo. Tissue blocks were inoculated with HIV-1. After productive infection was established, they were treated with the reverse transcriptase inhibitor nevirapine to protect from infection those CD4(+) T cells that had not yet been infected. These CD4(+) T cells residing in HIV-infected tissue are by definition bystanders. Our results demonstrate that after nevirapine application the number of bystander CD4(+) T cells is conserved. Thus, in the context of HIV-infected human lymphoid tissue, productive HIV infection kills infected cells but is not sufficient to cause the death of a significant number of uninfected CD4(+) T cells.

Bloodstream infection caused by nontoxigenic Corynebacterium diphtheriae in an immunocompromised host in the United States.

PubMed

Wojewoda, Christina M; Koval, Christine E; Wilson, Deborah A; Chakos, Mary H; Harrington, Susan M

2012-06-01

Corynebacterium species are well-known causes of catheter-related bloodstream infections. Toxigenic strains of Corynebacterium diphtheriae cause respiratory diphtheria. We report a bloodstream infection caused by a nontoxigenic strain of C. diphtheriae and discuss the epidemiology, possible sources of the infection, and the implications of rapid species identification of corynebacteria.

Bloodstream Infection Caused by Nontoxigenic Corynebacterium diphtheriae in an Immunocompromised Host in the United States

PubMed Central

Wojewoda, Christina M.; Koval, Christine E.; Wilson, Deborah A.; Chakos, Mary H.

2012-01-01

Corynebacterium species are well-known causes of catheter-related bloodstream infections. Toxigenic strains of Corynebacterium diphtheriae cause respiratory diphtheria. We report a bloodstream infection caused by a nontoxigenic strain of C. diphtheriae and discuss the epidemiology, possible sources of the infection, and the implications of rapid species identification of corynebacteria. PMID:22493337

Cofilin 1-Mediated Biphasic F-Actin Dynamics of Neuronal Cells Affect Herpes Simplex Virus 1 Infection and Replication

PubMed Central

Xiang, Yangfei; Zheng, Kai; Ju, Huaiqiang; Wang, Shaoxiang; Pei, Ying; Ding, Weichao; Chen, Zhenping; Wang, Qiaoli; Qiu, Xianxiu; Zhong, Meigong; Zeng, Fanli; Ren, Zhe; Qian, Chuiwen; Liu, Ge

2012-01-01

Herpes simplex virus 1 (HSV-1) invades the nervous system and causes pathological changes. In this study, we defined the remodeling of F-actin and its possible mechanisms during HSV-1 infection of neuronal cells. HSV-1 infection enhanced the formation of F-actin-based structures in the early stage of infection, which was followed by a continuous decrease in F-actin during the later stages of infection. The disruption of F-actin dynamics by chemical inhibitors significantly reduced the efficiency of viral infection and intracellular HSV-1 replication. The active form of the actin-depolymerizing factor cofilin 1 was found to increase at an early stage of infection and then to continuously decrease in a manner that corresponded to the remodeling pattern of F-actin, suggesting that cofilin 1 may be involved in the biphasic F-actin dynamics induced by HSV-1 infection. Knockdown of cofilin 1 impaired HSV-1-induced F-actin assembly during early infection and inhibited viral entry; however, overexpression of cofilin 1 did not affect F-actin assembly or viral entry during early infection but decreased intracellular viral reproduction efficiently. Our results, for the first time, demonstrated the biphasic F-actin dynamics in HSV-1 neuronal infection and confirmed the association of F-actin with the changes in the expression and activity of cofilin 1. These results may provide insight into the mechanism by which HSV-1 productively infects neuronal cells and causes pathogenesis. PMID:22623803

Hematoma and abscess formation caused by Mycoplasma hominis following cesarean section

PubMed Central

Koshiba, Hisato; Koshiba, Akemi; Daimon, Yasushi; Noguchi, Toshifumi; Iwasaku, Kazuhiro; Kitawaki, Jo

2011-01-01

Mycoplasma species cannot be identified by routine bacteriological culture methods and are resistant to common antimicrobial agents. Mycoplasma hominis usually colonizes the lower urogenital tract and causes pyelonephritis, pelvic inflammatory disease, chorioamnionitis, rupture of fetal membranes, preterm labor, postpartum fever, postabortal fever, and neonatal infection. This organism is highly prevalent in cervicovaginal cultures of sexually active women. M. hominis, M. genitalis, Ureaplasma urealyticum, and U. parvum may invade and infect placental and fetal tissues, leading to adverse pregnancy outcomes. M. hominis occasionally causes nongenitourinary infection of the blood, wounds, central nervous system, joints, or respiratory tract. We present a case of a 27-year-old woman who developed abdominal wound hematoma and abscess after cesarean section. The wound was drained, but her high fever persisted, in spite of antibiotic treatment using flomoxef sodium and imipenem·cilastatin sodium. Because the exudate exhibited M. hominis growth in an anaerobic environment, we administered the quinolone ciprofloxacin. This therapy resolved her fever, and her white blood cell count and C-reactive protein level diminished to the normal ranges. To our knowledge, there are four published articles regarding the isolation of M. hominis from postcesarean incisions. Based on the current study and the literature, infection by this pathogen may cause hematoma formation with or without abscess after cesarean section or in immunosuppressed postoperative patients. In such cases, physicians may need to suspect Mycoplasma infection and initiate appropriate antibacterial treatment as soon as possible in order to avoid persistent fever. PMID:21339933

SIV Infection Impairs the Central Nervous System in Chinese Rhesus Macaques.

PubMed

Liu, Hang; Xiao, Qian-Hao; Liu, Jin-Biao; Li, Jie-Liang; Zhou, Li; Xian, Qiao-Yang; Wang, Yong; Zhang, Jing; Wang, Xu; Ho, Wen-Zhe; Zhuang, Ke

2016-09-01

The central nervous system (CNS) impairment is a consequence seen in SIV infection of rhesus macaques of Indian-origin, which is more common in infected macaques with rapid disease progression than in those with conventional disease progression. Here, we investigated the CNS damages in SIVmac239-infected Chinese rhesus macaques. We demonstrated that SIV infection of Chinese macaques could cause neuropathological impairments, which was evidenced by appearance of SIV-RNA positive cells, the infiltration of activated macrophages and abundant multinucleated giant cells (MNGCs) in the different regions of the brains. The animals with high viremia and short survival time (average of 16 weeks, rapid progression, RP) had severer neuropathological changes than those with conventional progression (CP). As compared with the RP animals, CP macaques had lower viremia and much longer survival time (average of 154 weeks). These findings indicate that SIVmac239 infection of Chinese rhesus macaque can be used as a suitable animal model and alternative resource for nueroAIDS research.

Validation of reference genes for quantifying changes in gene expression in virus-infected tobacco.

PubMed

Baek, Eseul; Yoon, Ju-Yeon; Palukaitis, Peter

2017-10-01

To facilitate quantification of gene expression changes in virus-infected tobacco plants, eight housekeeping genes were evaluated for their stability of expression during infection by one of three systemically-infecting viruses (cucumber mosaic virus, potato virus X, potato virus Y) or a hypersensitive-response-inducing virus (tobacco mosaic virus; TMV) limited to the inoculated leaf. Five reference-gene validation programs were used to establish the order of the most stable genes for the systemically-infecting viruses as ribosomal protein L25 > β-Tubulin > Actin, and the least stable genes Ubiquitin-conjugating enzyme (UCE) < PP2A < GAPDH. For local infection by TMV, the most stable genes were EF1α > Cysteine protease > Actin, and the least stable genes were GAPDH < PP2A < UCE. Using two of the most stable and the two least stable validated reference genes, three defense responsive genes were examined to compare their relative changes in gene expression caused by each virus. Copyright © 2017 Elsevier Inc. All rights reserved.

The infectious origins of stillbirth.

PubMed

Goldenberg, Robert L; Thompson, Cortney

2003-09-01

Our objective was to determine the relationship between various types of perinatal infections and stillbirths. By use of various textbooks on perinatal infections, multiple MEDLINE searches, and the reference list of all appropriate manuscripts, the appropriate English language literature was reviewed to define the relationship between various perinatal infections and stillbirths. Infection may cause stillbirth by a number of mechanisms, including direct infection, placental damage, and severe maternal illness. A large variety of organisms have been associated with stillbirth, including many bacteria, viruses, and protozoa. In developed countries, between 10% and 25% of stillbirths may be caused by an infection, whereas in developing countries, which often have much higher stillbirth rates, the contribution of infection is much greater. Ascending bacterial infection, both before and after membrane rupture, with organisms such as Escherichia coli, group B streptococci, and Ureaplasma urealyticum is usually the most common infectious cause of stillbirth. However, in areas where syphilis is very prevalent, up to half of all stillbirths may be caused by this infection alone. Malaria may be an important cause of stillbirth in women infected for the first time in pregnancy. The two most important viral causes of stillbirth are parvovirus and Coxsackie virus, although a number of other viral infections appear to be causal. Toxoplasma gondii, leptospirosis, Listeria monocytogenes, and the organisms that cause leptospirosis, Q fever, and Lyme disease have all been implicated as etiologic for stillbirth. Because infection-related stillbirth is relatively rare in developed countries, and those that do occur are caused by a wide variety of organisms, reducing this etiologic component of stillbirth much further will be difficult. However, in certain developing countries, the stillbirth rate is so high and the infection-related component so great that achieving a substantial reduction in stillbirth should be possible simply by reducing maternal infections.

Use of Pneumococcal Disease Epidemiology to Set Policy and Prevent Disease during 20 Years of the Emerging Infections Program.

PubMed

Moore, Matthew R; Whitney, Cynthia G

2015-09-01

Two decades ago, the Emerging Infections Program of the US Centers for Disease Control and Prevention implemented what seemed like a simple yet novel idea: a population- and laboratory-based surveillance system designed to identify and characterize invasive bacterial infections, including those caused by Streptococcus pneumoniae. This system, known as Active Bacterial Core surveillance, has since served as a flexible platform for following trends in invasive pneumococcal disease and studying vaccination as the most effective method for prevention. We report the contributions of Active Bacterial Core surveillance to every pneumococcal vaccine policy decision in the United States during the past 20 years.

Urticaria pigmentosa

MedlinePlus

... occurs when there are too many inflammatory cells (mast cells) in the skin. Mast cells are immune system cells that help the body fight infections. Mast cells make and release histamine, which causes nearby tissues ...

Towards a Chlamydia trachomatis vaccine: how close are we?

PubMed

Cochrane, Melanie; Armitage, Charles W; O'Meara, Connor P; Beagley, Kenneth W

2010-12-01

Chlamydia trachomatis is the leading cause of bacterial sexually transmitted infections and preventable blindness worldwide. The incidence of chlamydial sexually transmitted infections has increased rapidly and current antibiotic therapy has failed as an intervention strategy. The most accepted strategy for protection and/or control of chlamydial infections is a vaccine that induces both local neutralizing antibodies to prevent infections by the extracellular elementary bodies and a cell-mediated immune response to target the intracellular infection. This article will discuss the challenges in vaccine design for the prevention of chlamydial urogenital infection and/or disease, including selection of target antigens, discussion of effective delivery systems, immunization routes and adjuvants for induction of protective immunity at the targeted mucosal surface whilst minimizing severe inflammatory disease sequelae.

Measles, mumps, rubella, and human parvovirus B19 infections and neurologic disease.

PubMed

Bale, James F

2014-01-01

While the systemic disorders associated with measles, mumps, and rubella viruses and human parvovirus B19 tend to be mild, each virus can produce potentially life-threatening neurologic disease in human hosts, especially when these viruses infect young children. Two of the viruses, rubella and parvovirus B19, can be vertically transmitted to fetuses during maternal infection and cause congenital infection. Neurologic complications are common after intrauterine infection with the rubella virus, a condition known as the congenital rubella syndrome. Two, measles and rubella viruses, can induce "slow viral" infections, serious, disorders that can occur several years after the initial exposure to the virus and typically have fatal outcomes. © 2014 Elsevier B.V. All rights reserved.

Fatal Systemic Salmonellosis in a Florida Manatee ( Trichechus manatus latirostris).

PubMed

Vorbach, Bryan S; Rotstein, David S; Stacy, Nicole I; Mavian, Carla; Salemi, Marco; Waltzek, Thomas B; de Wit, Martine

2017-10-01

A subadult male Florida manatee ( Trichechus manatus latirostris) stranded dead on Florida's Atlantic coast in January 2015. Necropsy and histopathologic findings confirmed chronic systemic bacterial infection caused by Salmonella enterica serotype IV 50:z4,z23,:- involving renal, respiratory, lymphatic, and skeletal systems. This was a unique case of systemic salmonellosis in a Florida manatee.

Undernutrition, the Acute Phase Response to Infection, and Its Effects on Micronutrient Status Indicators12

PubMed Central

Bresnahan, Kara A.; Tanumihardjo, Sherry A.

2014-01-01

Infection and undernutrition are prevalent in developing countries and demonstrate a synergistic relation. Undernutrition increases infection-related morbidity and mortality. The acute phase response (APR) is an innate, systemic inflammatory reaction to a wide array of disruptions in a host’s homeostasis, including infection. Released from immune cells in response to deleterious stimuli, proinflammatory cytokines act on distant tissues to induce behavioral (e.g., anorexia, weakness, and fatigue) and systemic effects of the APR. Cytokines act to increase energy and protein requirements to manifest fever and support hepatic acute phase protein (APP) production. Blood concentrations of glucose and lipid are augmented to provide energy to immune cells in response to cytokines. Additionally, infection decreases intestinal absorption of nutrients and can cause direct loss of micronutrients. Traditional indicators of iron, zinc, and vitamin A status are altered during the APR, leading to inaccurate estimations of deficiency in populations with a high or unknown prevalence of infection. Blood concentrations of APPs can be measured in nutrition interventions to assess the time stage and severity of infection and correct for the APR; however, standardized cutoffs for nutrition applications are needed. Protein-energy malnutrition leads to increased gut permeability to pathogens, abnormal immune cell populations, and impaired APP response. Micronutrient deficiencies cause specific immune impairments that affect both innate and adaptive responses. This review describes the antagonistic interaction between the APR and nutritional status and emphasizes the need for integrated interventions to address undernutrition and to reduce disease burden in developing countries. PMID:25398733

INFLUENCE OF ANESTHESIA ON EXPERIMENTAL NEUROTROPIC VIRUS INFECTIONS

PubMed Central

Sulkin, S. Edward; Zarafonetis, Christine; Goth, Andres

1946-01-01

Anesthesia with diethyl ether significantly alters the course and outcome of experimental infections with the equine encephalomyelitis virus (Eastern or Western type) or with the St. Louis encephalitis virus. No comparable effect is observed in experimental infections produced with rabies or poliomyelitis (Lansing) viruses. The neurotropic virus infections altered by ether anesthesia are those caused by viruses which are destroyed in vitro by this anesthetic, and those infections not affected by ether anesthesia are caused by viruses which apparently are not destroyed by ether in vitro. Another striking difference between these two groups of viruses is their pathogenesis in the animal host; those which are inhibited in vivo by ether anesthesia tend to infect cells of the cortex, basal ganglia, and only occasionally the cervical region of the cord. On the other hand, those which are not inhibited in vivo by ether anesthesia tend to involve cells of the lower central nervous system and in the case of rabies, peripheral nerves. This difference is of considerable importance in view of the fact that anesthetics affect cells of the lower central nervous system only in very high concentrations. It is obvious from the complexity of the problem that no clear-cut statement can be made at this point as to the mechanism of the observed effect of ether anesthesia in reducing the mortality rate in certain of the experimental neurotropic virus infections. Important possibilities include a direct specific effect of diethyl ether upon the virus and a less direct effect of the anesthetic upon the virus through its alteration of the metabolism of the host cell. PMID:19871570

Effects of temperature on Veronaea botryosa infections in white sturgeon Acipenser transmontanus and fungal induced cytotoxicity of fish cell lines.

PubMed

Coleman, Denver J; Camus, Alvin C; Martínez-López, Beatriz; Yun, Susan; Stevens, Brittany; Soto, Esteban

2018-02-01

Veronaea botryosa is a melanized mold and cause of systemic fungal infections in cultured sturgeon (Acipenser spp.). Mortality in adult female sturgeon caused by this emergent pathogen results in significant economic losses for the caviar industry. Little is known regarding environmental conditions conducive to V. botryosa infection. This study evaluated the effect of temperature on V. botryosa infectivity and dissemination following intramuscular injection challenge of white sturgeon maintained at 13 or 18 °C for 40 days. Daily mortality was recorded and persistence of the fungus in the livers of moribund and surviving fish was investigated using culture and histopathological analysis. Fish maintained at 18 °C developed systemic phaeohyphomycosis and had significantly greater mortality than controls and fish maintained at 13 °C (p < 0.05). Challenged fish, regardless of temperature, exhibited lesions in multiple organs. However, muscle lesions, angioinvasion, and systemic dissemination were more severe and widespread in fish challenged at the higher temperature. In vitro cytotoxicity of V. botryosa was evaluated in white sturgeon skin (WSSK-1) and epithelioma papulosum cyprini (EPC) cell lines inoculated at spore:cell ratios of 1:10, 1:1 and 10:1, then incubated 15, 20 and 25 °C. Cytotoxicity, as indicated by quantifying the release of lactate dehydrogenase into culture supernatants, increased with increasing spore dose and incubation temperature in both fish cell lines. Findings suggest that temperature significantly influences the development of systemic V. botryosa infection in white sturgeon and that WSSK-1 and EPC cells are suitable in vitro models for the study of host-pathogen interactions between V. botryosa and fish epithelial cells.

SdrF, a Staphylococcus epidermidis Surface Protein, Contributes to the Initiation of Ventricular Assist Device Driveline–Related Infections

PubMed Central

Arrecubieta, Carlos; Toba, Faustino A.; von Bayern, Manuel; Akashi, Hirokazu; Deng, Mario C.; Naka, Yoshifumi; Lowy, Franklin D.

2009-01-01

Staphylococcus epidermidis remains the predominant pathogen in prosthetic-device infections. Ventricular assist devices, a recently developed form of therapy for end-stage congestive heart failure, have had considerable success. However, infections, most often caused by Staphylococcus epidermidis, have limited their long-term use. The transcutaneous driveline entry site acts as a potential portal of entry for bacteria, allowing development of either localized or systemic infections. A novel in vitro binding assay using explanted drivelines obtained from patients undergoing transplantation and a heterologous lactococcal system of surface protein expression were used to identify S. epidermidis surface components involved in the pathogenesis of driveline infections. Of the four components tested, SdrF, SdrG, PIA, and GehD, SdrF was identified as the primary ligand. SdrF adherence was mediated via its B domain attaching to host collagen deposited on the surface of the driveline. Antibodies directed against SdrF reduced adherence of S. epidermidis to the drivelines. SdrF was also found to adhere with high affinity to Dacron, the hydrophobic polymeric outer surface of drivelines. Solid phase binding assays showed that SdrF was also able to adhere to other hydrophobic artificial materials such as polystyrene. A murine model of infection was developed and used to test the role of SdrF during in vivo driveline infection. SdrF alone was able to mediate bacterial adherence to implanted drivelines. Anti-SdrF antibodies reduced S. epidermidis colonization of implanted drivelines. SdrF appears to play a key role in the initiation of ventricular assist device driveline infections caused by S. epidermidis. This pluripotential adherence capacity provides a potential pathway to infection with SdrF-positive commensal staphylococci first adhering to the external Dacron-coated driveline at the transcutaneous entry site, then spreading along the collagen-coated internal portion of the driveline to establish a localized infection. This capacity may also have relevance for other prosthetic device–related infections. PMID:19412528

Serum Metabolic Profiling of Oocyst-Induced Toxoplasma gondii Acute and Chronic Infections in Mice Using Mass-Spectrometry

PubMed Central

Zhou, Chun-Xue; Cong, Wei; Chen, Xiao-Qing; He, Shen-Yi; Elsheikha, Hany M.; Zhu, Xing-Quan

2018-01-01

Toxoplasma gondii is an obligate intracellular parasite causing severe diseases in immunocompromised individuals and congenitally infected neonates, such as encephalitis and chorioretinitis. This study aimed to determine whether serum metabolic profiling can (i) identify metabolites associated with oocyst-induced T. gondii infection and (ii) detect systemic metabolic differences between T. gondii-infected mice and controls. We performed the first global metabolomics analysis of mice serum challenged with 100 sporulated T. gondii Pru oocysts (Genotype II). Sera from acutely infected mice (11 days post-infection, dpi), chronically infected mice (33 dpi) and control mice were collected and analyzed using LC-MS/MS platform. Following False Discovery Rate filtering, we identified 3871 and 2825 ions in ESI+ or ESI− mode, respectively. Principal Component Analysis (PCA) and Partial Least Squares Discriminant Analysis (PLS-DA) identified metabolomic profiles that clearly differentiated T. gondii-infected and -uninfected serum samples. Acute infection significantly influenced the serum metabolome. Our results identified common and uniquely perturbed metabolites and pathways. Acutely infected mice showed perturbations in metabolites associated with glycerophospholipid metabolism, biosynthesis of amino acid, and tyrosine metabolism. These findings demonstrated that acute T. gondii infection induces a global perturbation of mice serum metabolome, providing new insights into the mechanisms underlying systemic metabolic changes during early stage of T. gondii infection. PMID:29354104

Far East Scarlet-Like Fever: A Review of the Epidemiology, Symptomatology, and Role of Superantigenic Toxin: Yersinia pseudotuberculosis-Derived Mitogen A

PubMed Central

Amphlett, A.

2016-01-01

Far East scarlet-like fever (FESLF) is a severe inflammatory disease that occurs sporadically and in outbreaks in Russia and Japan. Far East scarlet-like fever is caused by Yersinia pseudotubuclosis infection, an organism that typically causes self-limiting gastroenteritis in Europe. Studies suggest the ability of Far Eastern strains to produce superantigen toxin Y pseudotuberculosis-derived mitogen A is integral to FESLF pathogenesis. In Europe, human Y pseudotuberculosis infection typically occurs sporadically, in the form of a self-limiting gastroenteritis. In Russia and Japan, outbreaks of Y pseudotuberculosis infection cause severe systemic inflammatory symptoms. This disease variant is called FESLF. Geographical heterogeneity exists between virulence factors produced by European and Far Eastern Y pseudotuberculosis strains, implicating superantigen Y pseudotuberculosis-derived mitogen A (YPMa) in the pathogenesis of FESLF. This article describes the epidemiology and clinical features of FESLF, and it presents the evidence for the role of YPMa in FESLF pathogenesis. PMID:26819960

Far East Scarlet-Like Fever: A Review of the Epidemiology, Symptomatology, and Role of Superantigenic Toxin: Yersinia pseudotuberculosis-Derived Mitogen A.

PubMed

Amphlett, A

2016-01-01

Far East scarlet-like fever (FESLF) is a severe inflammatory disease that occurs sporadically and in outbreaks in Russia and Japan. Far East scarlet-like fever is caused by Yersinia pseudotubuclosis infection, an organism that typically causes self-limiting gastroenteritis in Europe. Studies suggest the ability of Far Eastern strains to produce superantigen toxin Y pseudotuberculosis-derived mitogen A is integral to FESLF pathogenesis. In Europe, human Y pseudotuberculosis infection typically occurs sporadically, in the form of a self-limiting gastroenteritis. In Russia and Japan, outbreaks of Y pseudotuberculosis infection cause severe systemic inflammatory symptoms. This disease variant is called FESLF. Geographical heterogeneity exists between virulence factors produced by European and Far Eastern Y pseudotuberculosis strains, implicating superantigen Y pseudotuberculosis-derived mitogen A (YPMa) in the pathogenesis of FESLF. This article describes the epidemiology and clinical features of FESLF, and it presents the evidence for the role of YPMa in FESLF pathogenesis.

Sepsis in acute myeloid leukaemia patients receiving high-dose chemotherapy: no impact of chitotriosidase and mannose-binding lectin polymorphisms.

PubMed

Klostergaard, Anja; Steffensen, Rudi; Møller, Jens K; Peterslund, Niels; Juhl-Christensen, Caroline; Mølle, Ingolf

2010-07-01

Infections after chemotherapy often cause significant morbidity in patients with acute myeloid leukaemia (AML). Chitotriosidase (CHIT) and mannose-binding lectin (MBL) are part of the innate immune system. Polymorphism in the CHIT-coding gene (CHIT1) may be associated with Gram-negative sepsis in children with AML, and polymorphism in the MBL-coding gene (MBL2) seems to modify the risk of infections in several patient groups. The purpose of this study was to investigate the possible associations between polymorphisms in CHIT1, MBL2 and sepsis in adult patients treated with high-dose chemotherapy for AML. We included 190 patients treated with 526 cycles of chemotherapy. The follow-up period was 6 months from the diagnosis of AML. Prophylactic antibiotics were not used. We identified 604 febrile episodes with 246 episodes of sepsis. Thirty-two patients (17%) either died from infection or infection was a major concomitant factor for death. No significant associations between CHIT1 polymorphism and sepsis (P = 0.85) or death caused by sepsis (P = 0.14) were found. Furthermore, no significant associations between MBL2 polymorphism and sepsis (P = 0.76) or death caused by sepsis (P = 0.24) were observed. The severe and long-lasting neutropenia and mucositis after chemotherapy may explain why the MBL system does not protect against sepsis in patients with AML. Replacement therapy with recombinant MBL is not likely to decrease the risk of sepsis in patients with AML.

How compelling are the data for Epstein-Barr virus being a trigger for systemic lupus and other autoimmune diseases?

PubMed

Draborg, Anette; Izarzugaza, Jose M G; Houen, Gunnar

2016-07-01

Systemic lupus erythematosus (SLE) is caused by a combination of genetic and acquired immunodeficiencies and environmental factors including infections. An association with Epstein-Barr virus (EBV) has been established by numerous studies over the past decades. Here, we review recent experimental studies on EBV, and present our integrated theory of SLE development. SLE patients have dysfunctional control of EBV infection resulting in frequent reactivations and disease progression. These comprise impaired functions of EBV-specific T-cells with an inverse correlation to disease activity and elevated serum levels of antibodies against lytic cycle EBV antigens. The presence of EBV proteins in renal tissue from SLE patients with nephritis suggests direct involvement of EBV in SLE development. As expected for patients with immunodeficiencies, studies reveal that SLE patients show dysfunctional responses to other viruses as well. An association with EBV infection has also been demonstrated for other autoimmune diseases, including Sjögren's syndrome, rheumatoid arthritis, and multiple sclerosis. Collectively, the interplay between an impaired immune system and the cumulative effects of EBV and other viruses results in frequent reactivation of EBV and enhanced cell death, causing development of SLE and concomitant autoreactivities.

Aloe vera enhances the innate immune response of pacu (Piaractus mesopotamicus) after transport stress and combined heat killed Aeromonas hydrophila infection.

PubMed

Zanuzzo, Fábio S; Sabioni, Rafael E; Montoya, Luz Natalia F; Favero, Gisele; Urbinati, Elisabeth C

2017-06-01

In this study, pacu (Piaractus mesopotamicus) were fed with diets containing Aloe vera for 10 days prior to transport stress and infection with heat killed Aeromonas hydrophila. A. vera is popular around the world due to its medicinal properties, including immunostimulatory effects which was observed in this study. The results show that transport causes immunosuppression, an effect that was prevented by A. vera. Specifically, A. vera prevented reductions of both leukocyte respiratory burst and hemolytic activity of complement system caused by transport. Further, fish fed with A. vera also showed significantly higher leukocyte respiratory burst, serum lysozyme concentrations and activity of complement system 24 h after bacterial infection. Additionally, we observed that A. vera may modulate the innate response through activation of complement system during bacterial immune stimulation. In summary, A. vera extract enhanced innate immune parameters and consequently the ability of fish to cope with pathogens following transport stress. These findings show that A. vera has promise for use in aquaculture and add further evidence that medicinal herbs added to fish feed assist to prevent disease outbreaks. Copyright © 2017 Elsevier Ltd. All rights reserved.

Vaccines and the infant's immune system--what nurses need to know.

PubMed

Heurter, Helen; Langman, Eileen

2005-01-01

Vaccines prevent serious infections by stimulating the immune system to identify and destroy invading organisms rapidly before they have a chance to cause disease. Armed with the scientific facts to refute current misconceptions surrounding vaccines and the infant's immune system, nurses can provide parents with the answers they need.

Viral Infection of the Central Nervous System and Neuroinflammation Precede Blood-Brain Barrier Disruption during Japanese Encephalitis Virus Infection.

PubMed

Li, Fang; Wang, Yueyun; Yu, Lan; Cao, Shengbo; Wang, Ke; Yuan, Jiaolong; Wang, Chong; Wang, Kunlun; Cui, Min; Fu, Zhen F

2015-05-01

Japanese encephalitis is an acute zoonotic, mosquito-borne disease caused by Japanese encephalitis virus (JEV). Japanese encephalitis is characterized by extensive inflammation in the central nervous system (CNS) and disruption of the blood-brain barrier (BBB). However, the pathogenic mechanisms contributing to the BBB disruption are not known. Here, using a mouse model of intravenous JEV infection, we show that virus titers increased exponentially in the brain from 2 to 5 days postinfection. This was accompanied by an early, dramatic increase in the level of inflammatory cytokines and chemokines in the brain. Enhancement of BBB permeability, however, was not observed until day 4, suggesting that viral entry and the onset of inflammation in the CNS occurred prior to BBB damage. In vitro studies revealed that direct infection with JEV could not induce changes in the permeability of brain microvascular endothelial cell monolayers. However, brain extracts derived from symptomatic JEV-infected mice, but not from mock-infected mice, induced significant permeability of the endothelial monolayer. Consistent with a role for inflammatory mediators in BBB disruption, the administration of gamma interferon-neutralizing antibody ameliorated the enhancement of BBB permeability in JEV-infected mice. Taken together, our data suggest that JEV enters the CNS, propagates in neurons, and induces the production of inflammatory cytokines and chemokines, which result in the disruption of the BBB. Japanese encephalitis (JE) is the leading cause of viral encephalitis in Asia, resulting in 70,000 cases each year, in which approximately 20 to 30% of cases are fatal, and a high proportion of patients survive with serious neurological and psychiatric sequelae. Pathologically, JEV infection causes an acute encephalopathy accompanied by BBB dysfunction; however, the mechanism is not clear. Thus, understanding the mechanisms of BBB disruption in JEV infection is important. Our data demonstrate that JEV gains entry into the CNS prior to BBB disruption. Furthermore, it is not JEV infection per se, but the inflammatory cytokines/chemokines induced by JEV infection that inhibit the expression of TJ proteins and ultimately result in the enhancement of BBB permeability. Neutralization of gamma interferon (IFN-γ) ameliorated the enhancement of BBB permeability in JEV-infected mice, suggesting that IFN-γ could be a potential therapeutic target. This study would lead to identification of potential therapeutic avenues for the treatment of JEV infection. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

Transcriptome comparison and gene coexpression network analysis provide a systems view of citrus response to ‘Candidatus Liberibacter asiaticus’ infection

PubMed Central

2013-01-01

Background Huanglongbing (HLB) is arguably the most destructive disease for the citrus industry. HLB is caused by infection of the bacterium, Candidatus Liberibacter spp. Several citrus GeneChip studies have revealed thousands of genes that are up- or down-regulated by infection with Ca. Liberibacter asiaticus. However, whether and how these host genes act to protect against HLB remains poorly understood. Results As a first step towards a mechanistic view of citrus in response to the HLB bacterial infection, we performed a comparative transcriptome analysis and found that a total of 21 Probesets are commonly up-regulated by the HLB bacterial infection. In addition, a number of genes are likely regulated specifically at early, late or very late stages of the infection. Furthermore, using Pearson correlation coefficient-based gene coexpression analysis, we constructed a citrus HLB response network consisting of 3,507 Probesets and 56,287 interactions. Genes involved in carbohydrate and nitrogen metabolic processes, transport, defense, signaling and hormone response were overrepresented in the HLB response network and the subnetworks for these processes were constructed. Analysis of the defense and hormone response subnetworks indicates that hormone response is interconnected with defense response. In addition, mapping the commonly up-regulated HLB responsive genes into the HLB response network resulted in a core subnetwork where transport plays a key role in the citrus response to the HLB bacterial infection. Moreover, analysis of a phloem protein subnetwork indicates a role for this protein and zinc transporters or zinc-binding proteins in the citrus HLB defense response. Conclusion Through integrating transcriptome comparison and gene coexpression network analysis, we have provided for the first time a systems view of citrus in response to the Ca. Liberibacter spp. infection causing HLB. PMID:23324561

Candida-induced prosthetic joint infection. A literature review including 72 cases and a case report.

PubMed

Cobo, Fernando; Rodríguez-Granger, Javier; López, Enrique M; Jiménez, Gemma; Sampedro, Antonio; Aliaga-Martínez, Luis; Navarro-Marí, José María

2017-02-01

The clinical and microbiological characteristics of prosthetic joint infection (PJI) caused by Candida species is described, including 72 cases in the literature and a case of Candida glabrata infection handled at the present centre. We describe one patient and using the key words 'fungal prosthetic joint infection' and 'candida prosthetic joint infection' we searched MEDLINE (National Library of Medicine, Bethesda, MD), Web of Science, CINAHL and Cochrane systematic review databases for case reports of this condition. Out of the 73 patients, 38 were female; mean age at diagnosis was 65.7 (± SD 18) yrs; 50 had risk factors for candidal infection such as systemic disease (e.g. rheumatoid arthritis, Sjogren's syndrome, systemic lupus erythematosus) and/or immunosuppressive therapy in 18 (24.6%) cases, diabetes mellitus in 14 (19.1%), immunosuppression due to malignant or chronic disease in 24 (32.8%) and long-term antibiotic use in four (5.4%) patients. Infection site was the knee in 36 patients and hip in 35; pain was present in 43 patients and swelling in 23 and the mean surgery-diagnosis interval was 32 months. The most frequent species was C. albicans, followed by C. parapsilosis. The diagnosis was obtained from joint fluid aspirate in 33 cases and intra-operative samples in 16. Susceptibility to antifungals was tested in only 21 isolates. The most frequently used antifungals were fluconazole and amphotericin B. Two-stage exchange arthroplasty was performed in 30 patients and resection arthroplasty in 31; 56 patients were cured with a combination of medical and surgical treatment; one patient died from the infection. PJI caused by Candida requires a high index of suspicion; surgery with long-term antifungal therapy is recommended.

Hansen’s Disease with HIV: A Case of Immune Reconstitution Disease

PubMed Central

Chow, Dominic; Okinaka, Leila; Souza, Scott; Shikuma, Cecilia; Tice, Alan

2009-01-01

Immune reconstitution inflammatory syndrome (IRIS) is an acute symptomatic expression of a latent infection during the recovery of the immune system usually as a response to antiretroviral therapy (ART). Opportunistic infections can trigger IRIS. Hansen’s disease is an infection caused by Mycobacterium leprae (M. leprae). There have been a limited number of case reports reporting the presentation of the co-infection of HIV and M. leprae. We report an unique case of IRIS in a patient co-infected with HIV and M. leprae presenting as an exacerbation of his Hansen’s Disease where the patient’s skin lesions progressed from borderline tuberculoid to lepromatous leprosy following ART administration. PMID:19385373

Acute Hepatopancreatic Necrosis Disease-Causing Vibrio parahaemolyticus Strains Maintain an Antibacterial Type VI Secretion System with Versatile Effector Repertoires.

PubMed

Li, Peng; Kinch, Lisa N; Ray, Ann; Dalia, Ankur B; Cong, Qian; Nunan, Linda M; Camilli, Andrew; Grishin, Nick V; Salomon, Dor; Orth, Kim

2017-07-01

Acute hepatopancreatic necrosis disease (AHPND) is a newly emerging shrimp disease that has severely damaged the global shrimp industry. AHPND is caused by toxic strains of Vibrio parahaemolyticus that have acquired a "selfish plasmid" encoding the deadly binary toxins PirA vp /PirB vp To better understand the repertoire of virulence factors in AHPND-causing V. parahaemolyticus , we conducted a comparative analysis using the genome sequences of the clinical strain RIMD2210633 and of environmental non-AHPND and toxic AHPND isolates of V. parahaemolyticus Interestingly, we found that all of the AHPND strains, but none of the non-AHPND strains, harbor the antibacterial type VI secretion system 1 (T6SS1), which we previously identified and characterized in the clinical isolate RIMD2210633. This finding suggests that the acquisition of this T6SS might confer to AHPND-causing V. parahaemolyticus a fitness advantage over competing bacteria and facilitate shrimp infection. Additionally, we found highly dynamic effector loci in the T6SS1 of AHPND-causing strains, leading to diverse effector repertoires. Our discovery provides novel insights into AHPND-causing pathogens and reveals a potential target for disease control. IMPORTANCE Acute hepatopancreatic necrosis disease (AHPND) is a serious disease that has caused severe damage and significant financial losses to the global shrimp industry. To better understand and prevent this shrimp disease, it is essential to thoroughly characterize its causative agent, Vibrio parahaemolyticus Although the plasmid-encoded binary toxins PirA vp /PirB vp have been shown to be the primary cause of AHPND, it remains unknown whether other virulent factors are commonly present in V. parahaemolyticus and might play important roles during shrimp infection. Here, we analyzed the genome sequences of clinical, non-AHPND, and AHPND strains to characterize their repertoires of key virulence determinants. Our studies reveal that an antibacterial type VI secretion system is associated with the AHPND strains and differentiates them from non-AHPND strains, similar to what was seen with the PirA/PirB toxins. We propose that T6SS1 provides a selective advantage during shrimp infections. Copyright © 2017 American Society for Microbiology.

Acute Hepatopancreatic Necrosis Disease-Causing Vibrio parahaemolyticus Strains Maintain an Antibacterial Type VI Secretion System with Versatile Effector Repertoires

PubMed Central

Li, Peng; Kinch, Lisa N.; Ray, Ann; Dalia, Ankur B.; Nunan, Linda M.; Camilli, Andrew; Grishin, Nick V.

2017-01-01

ABSTRACT Acute hepatopancreatic necrosis disease (AHPND) is a newly emerging shrimp disease that has severely damaged the global shrimp industry. AHPND is caused by toxic strains of Vibrio parahaemolyticus that have acquired a “selfish plasmid” encoding the deadly binary toxins PirAvp/PirBvp. To better understand the repertoire of virulence factors in AHPND-causing V. parahaemolyticus, we conducted a comparative analysis using the genome sequences of the clinical strain RIMD2210633 and of environmental non-AHPND and toxic AHPND isolates of V. parahaemolyticus. Interestingly, we found that all of the AHPND strains, but none of the non-AHPND strains, harbor the antibacterial type VI secretion system 1 (T6SS1), which we previously identified and characterized in the clinical isolate RIMD2210633. This finding suggests that the acquisition of this T6SS might confer to AHPND-causing V. parahaemolyticus a fitness advantage over competing bacteria and facilitate shrimp infection. Additionally, we found highly dynamic effector loci in the T6SS1 of AHPND-causing strains, leading to diverse effector repertoires. Our discovery provides novel insights into AHPND-causing pathogens and reveals a potential target for disease control. IMPORTANCE Acute hepatopancreatic necrosis disease (AHPND) is a serious disease that has caused severe damage and significant financial losses to the global shrimp industry. To better understand and prevent this shrimp disease, it is essential to thoroughly characterize its causative agent, Vibrio parahaemolyticus. Although the plasmid-encoded binary toxins PirAvp/PirBvp have been shown to be the primary cause of AHPND, it remains unknown whether other virulent factors are commonly present in V. parahaemolyticus and might play important roles during shrimp infection. Here, we analyzed the genome sequences of clinical, non-AHPND, and AHPND strains to characterize their repertoires of key virulence determinants. Our studies reveal that an antibacterial type VI secretion system is associated with the AHPND strains and differentiates them from non-AHPND strains, similar to what was seen with the PirA/PirB toxins. We propose that T6SS1 provides a selective advantage during shrimp infections. PMID:28432099

Differences in the causes of death of HIV-positive patients in a cohort study by data sources and coding algorithms.

PubMed

Hernando, Victoria; Sobrino-Vegas, Paz; Burriel, M Carmen; Berenguer, Juan; Navarro, Gemma; Santos, Ignacio; Reparaz, Jesús; Martínez, M Angeles; Antela, Antonio; Gutiérrez, Félix; del Amo, Julia

2012-09-10

To compare causes of death (CoDs) from two independent sources: National Basic Death File (NBDF) and deaths reported to the Spanish HIV Research cohort [Cohort de adultos con infección por VIH de la Red de Investigación en SIDA CoRIS)] and compare the two coding algorithms: International Classification of Diseases, 10th revision (ICD-10) and revised version of Coding Causes of Death in HIV (revised CoDe). Between 2004 and 2008, CoDs were obtained from the cohort records (free text, multiple causes) and also from NBDF (ICD-10). CoDs from CoRIS were coded according to ICD-10 and revised CoDe by a panel. Deaths were compared by 13 disease groups: HIV/AIDS, liver diseases, malignancies, infections, cardiovascular, blood disorders, pulmonary, central nervous system, drug use, external, suicide, other causes and ill defined. There were 160 deaths. Concordance for the 13 groups was observed in 111 (69%) cases for the two sources and in 115 (72%) cases for the two coding algorithms. According to revised CoDe, the commonest CoDs were HIV/AIDS (53%), non-AIDS malignancies (11%) and liver related (9%), these percentages were similar, 57, 10 and 8%, respectively, for NBDF (coded as ICD-10). When using ICD-10 to code deaths in CoRIS, wherein HIV infection was known in everyone, the proportion of non-AIDS malignancies was 13%, liver-related accounted for 3%, while HIV/AIDS reached 70% due to liver-related, infections and ill-defined causes being coded as HIV/AIDS. There is substantial variation in CoDs in HIV-infected persons according to sources and algorithms. ICD-10 in patients known to be HIV-positive overestimates HIV/AIDS-related deaths at the expense of underestimating liver-related diseases, infections and ill defined causes. CoDe seems as the best option for cohort studies.

Brain Malformations

MedlinePlus

Most brain malformations begin long before a baby is born. Something damages the developing nervous system or causes it ... medicines, infections, or radiation during pregnancy interferes with brain development. Parts of the brain may be missing, ...

Aetiology of obstructive azoospermia in Chinese infertility patients.

PubMed

Han, H; Liu, S; Zhou, X-G; Tian, L; Zhang, X-D

2016-09-01

To explore the aetiology of obstructive azoospermia (OA) in Chinese infertility patients, 133 OA patients was included in this study diagnosed and evaluated by one major specialist trained urological infertility. We retrospected the medical records to collect relative information. All of the patients had been underwent physical examination, ultrasound scan to the urogenital system, serum hormone tests, genetic tests and two separate semen analyses. The mean age of all 133 patients was 32.7 ± 6.8 years. A total of 266 reproductive tract units (two/patient) were classified into four categories: no causes (Idiopathic) for 74 units (27.8%), single cause for 173 units (65.0%), double causes for 17 units (6.4%) and triple causes for two units (0.8%). As to single cause of OA, there were four types: trauma for 0 unit (0%), infection for 125 units (47.0%), dysplasia for 11 units (4.1%) and surgeries for 37 units (13.9%). As to total cause of OA, there were five types: infection for 144 units (54.1%), orchitis for 51 units (19.2%), epididymitis for 54 units (20.3%), gonorrhoea for 28 units (10.5%) and inguinal hernia repair surgery for 18 units (6.8%). The most frequent cause of obstructive azoospermia was infection revealed in these Chinese infertility populations, followed by idiopathic reason. © 2015 Blackwell Verlag GmbH.

[Surveillance of infection events in neonatal intensive care].

PubMed

Decembrino, L; Perrini, S; Stronati, M

2010-06-01

Nosocomial infections are one of the major causes of morbidity and mortality in the newborn intensive care unit (NICU). They result in prolonged hospital stays and increased hospital costs. Neonates are susceptible hosts because of prematurity of organ systems, immaturity of immune system, low birth weight and the use of invasive devices. Most infections are endemic others can occur during outbreaks. As advances in medical technology improve mortality in the tiniest of infants, it is imperative that health care providers identify effective interventions to minimize the risks of nosocomial infections in the NICU. Recommended infection control and prevention strategies are: hand washing promotion, decreased use of invasive procedures, limited antitibiotic exposure, environmental hygiene. In this context infection surveillance is the first step to recognize and analyze problems, to effectively target infection control measures and feedback. Any suspicion of an outbreak should lead to a review of general infection control procedures to prevent the spread of the pathogens as quickly as possible. A multidisciplinary approach can be an effective means of developing a plan of action to apply prolonged and strict adherence to isolation precautions', to detect potential reservoirs or source of infections, to educate every member of the patient care team and to review NICU protocols.

Difficult clinical management of antituberculosis DRESS syndrome complicated by MRSA infection: A case report.

PubMed

Wang, Li; Li, Lin-Feng

2017-03-01

Drug reaction with eosinophilia and systemic symptoms (DRESS) syndrome is a severe drug-induced hypersensitivity reaction characterized by skin rash, fever, blood abnormalities, and multiple organ involvement. The diagnosis of DRESS syndrome is often delayed because of its variable presentation. Prompt withdrawal of the culprit drug is the definitive treatment. DRESS syndrome induced by antituberculosis drugs has rarely been reported. A 50-year-old man admitted to our hospital with recurrent episodes of progressive rash, fever, eosinophilia, lymphadenopathy, hepatic, and pulmonary involvement were experienced after repeat trials of the same antituberculosis drugs. We diagnosed it as DRESS caused by antituberculosis drugs. The case responded well to treatment with systemic corticosteroids and intravenous immunoglobulins. However, repeated bouts of infection with methicillin-resistant Staphylococcus aureus occurred during treatment (clavicular osteomyelitis and knee septic arthritis). He was cured after treatment with linezolid. The patient was discharged on day 112. At 8-month follow-up, there was no relapse of drug eruption and joint swelling. Early diagnosis and prompt withdrawal of all suspected drugs is a key tenet of the treatment of DRESS. Our case report highlights the risks inherent in delayed diagnosis of DRESS and the challenges in the clinical management of this condition. Pulmonary manifestations with radiological changes on chest X-ray and CT can be seen in DRESS. These changes need to be differentiated from those caused by pulmonary infections. Clavicular osteomyelitis infected with MRSA may be caused by iatrogenic injury during subclavian vein catheterization. This type of MRSA infections should be treated for 4 to 6 weeks. Blood eosinophilia could be a useful marker of disease progression and treatment response in patients with DRESS. However, more experience and clinical evidence is needed to confirm this.

Serological detection and epidemiology of Neospora caninum and Cryptosporidium parvum antibodies in cattle in southern Egypt.

PubMed

Fereig, Ragab M; AbouLaila, Mahmoud Rezk; Mohamed, Samy G A; Mahmoud, Hassan Y A H; Ali, Alsagher O; Ali, Asmaa F; Hilali, Mosaad; Zaid, Anis; Mohamed, Adel Elsayed Ahmed; Nishikawa, Yoshifumi

2016-10-01

Neospora caninum and Cryptosporidium parvum are intracellular protozoan parasites that are distributed worldwide and of major economical concern in cattle industry. N. caninum can cause abortion storms and high culling rates, whereas C. parvum has zoonotic implications and can cause diarrhea in calves. There are currently no data on the prevalence of neosporosis and cryptosporidiosis in humans or animals in southern Egypt. Prevalence of these two infections was determined in a sample of cattle from two different areas in southern Egypt, Sohag and Qena, using enzyme-linked immunosorbent assay. A total 301 cattle were sampled, of which 18.9% were positive for N. caninum, 35.9% were positive for C. parvum and 10.0% were positive for both. Geographical location and breeding system were considered as potential risk factors for C. parvum infection. A higher prevalence of infection was identified on small scale farms, compared with larger, intensive systems, with a prevalence of 50.2% compared with 37.8%, respectively. Animals in Sohag had a significantly higher prevalence compared with Qena, with a seroprevalence of 46.1% compared with 31.6%, respectively. In brief, marked seroprevalence recorded in this study indicates a high incidence of N. caninum and C. parvum infections in cattle, and this necessitates the application of more effective strategies for combating these types of infections on farms in Egypt. Copyright © 2016 Elsevier B.V. All rights reserved.

The use of microRNA by human viruses: lessons from NK cells and HCMV infection.

PubMed

Goldberger, Tal; Mandelboim, Ofer

2014-11-01

Depending on ethnicity and on social conditions, between 40 and 90 % of the population is infected with human cytomegalovirus (HCMV). In immunocompetent patients, the virus may cause an acute disease and then revert to a state of latency, which enables its coexistence with the human host. However, in cases of immunosuppression or in neonatal infections, HCMV can cause serious long-lasting illnesses. HCMV has developed multiple mechanisms in order to escape its elimination by the immune system, specifically by two killer cell types of the adaptive and the innate immune systems; cytotoxic T lymphocytes (CTL) and natural killer (NK) cells, respectively. Another fascinating aspect of HCMV is that like other highly developed herpesviruses, it expresses its own unique set of microRNAs. Here, we initially describe how the activity of NK cells is regulated under normal conditions and during infection. Then, we discuss what is currently known about HCMV microRNA-mediated interactions, with special emphasis on immune modulation and NK cell evasion. We further illustrate the significant modulation of cellular microRNAs during HCMV infection. Although, the full target spectrum of HCMV microRNAs is far from being completely elucidated, it can already be concluded that HCMV uses its "multitasking" microRNAs to globally affect its own life cycle, as well as important cellular and immune-related pathways.

Rice-Infecting Pseudomonas Genomes Are Highly Accessorized and Harbor Multiple Putative Virulence Mechanisms to Cause Sheath Brown Rot.

PubMed

Quibod, Ian Lorenzo; Grande, Genelou; Oreiro, Eula Gems; Borja, Frances Nikki; Dossa, Gerbert Sylvestre; Mauleon, Ramil; Cruz, Casiana Vera; Oliva, Ricardo

2015-01-01

Sheath rot complex and seed discoloration in rice involve a number of pathogenic bacteria that cannot be associated with distinctive symptoms. These pathogens can easily travel on asymptomatic seeds and therefore represent a threat to rice cropping systems. Among the rice-infecting Pseudomonas, P. fuscovaginae has been associated with sheath brown rot disease in several rice growing areas around the world. The appearance of a similar Pseudomonas population, which here we named P. fuscovaginae-like, represents a perfect opportunity to understand common genomic features that can explain the infection mechanism in rice. We showed that the novel population is indeed closely related to P. fuscovaginae. A comparative genomics approach on eight rice-infecting Pseudomonas revealed heterogeneous genomes and a high number of strain-specific genes. The genomes of P. fuscovaginae-like harbor four secretion systems (Type I, II, III, and VI) and other important pathogenicity machinery that could probably facilitate rice colonization. We identified 123 core secreted proteins, most of which have strong signatures of positive selection suggesting functional adaptation. Transcript accumulation of putative pathogenicity-related genes during rice colonization revealed a concerted virulence mechanism. The study suggests that rice-infecting Pseudomonas causing sheath brown rot are intrinsically diverse and maintain a variable set of metabolic capabilities as a potential strategy to occupy a range of environments.

An in-situ infection detection sensor coating for urinary catheters.

PubMed

Milo, Scarlet; Thet, Naing Tun; Liu, Dan; Nzakizwanayo, Jonathan; Jones, Brian V; Jenkins, A Toby A

2016-07-15

We describe a novel infection-responsive coating for urinary catheters that provides a clear visual early warning of Proteus mirabilis infection and subsequent blockage. The crystalline biofilms of P. mirabilis can cause serious complications for patients undergoing long-term bladder catheterisation. Healthy urine is around pH 6, bacterial urease increases urine pH leading to the precipitation of calcium and magnesium deposits from the urine, resulting in dense crystalline biofilms on the catheter surface that blocks urine flow. The coating is a dual layered system in which the lower poly(vinyl alcohol) layer contains the self-quenching dye carboxyfluorescein. This is capped by an upper layer of the pH responsive polymer poly(methyl methacrylate-co-methacrylic acid) (Eudragit S100®). Elevation of urinary pH (>pH 7) dissolves the Eudragit layer, releasing the dye to provide a clear visual warning of impending blockage. Evaluation of prototype coatings using a clinically relevant in vitro bladder model system demonstrated that coatings provide up to 12h advanced warning of blockage, and are stable both in the absence of infection, and in the presence of species that do not cause catheter blockage. At the present time, there are no effective methods to control these infections or provide warning of impending catheter blockage. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

Therapeutic effect of cefozopran (SCE-2787), a new parenteral cephalosporin, against experimental infections in mice.

PubMed Central

Iizawa, Y; Okonogi, K; Hayashi, R; Iwahi, T; Yamazaki, T; Imada, A

1993-01-01

The therapeutic effect of cefozopran (SCE-2787), a new semisynthetic parenteral cephalosporin, against experimental infections in mice was examined. Cefozopran was more effective than cefpiramide and was as effective as ceftazidime and cefpirome against acute respiratory tract infections caused by Klebsiella pneumoniae DT-S. In the model of chronic respiratory tract infection caused by K. pneumoniae 27, cefozopran was as effective as ceftazidime. The therapeutic effect of cefozopran against urinary tract infections caused by Pseudomonas aeruginosa P9 was superior to that of cefpirome and was equal to those of ceftazidime and cefclidin. In addition, cefozopran was more effective than ceftazidime and was as effective as flomoxef in a thigh muscle infection caused by methicillin-sensitive Staphylococcus aureus 308A-1. Against thigh muscle infections caused by methicillin-resistant S. aureus N133, cefozopran was the most effective agent. The potent therapeutic effect of cefozopran in those experimental infections in mice suggests that it would be effective against respiratory tract, urinary tract, and soft tissue infections caused by a variety of gram-positive and gram-negative bacteria in humans. PMID:8431004

Emergence of African species of dermatophytes in tinea capitis: A 17-year experience in a Montreal pediatric hospital.

PubMed

Marcoux, Danielle; Dang, Julie; Auguste, Hedwige; McCuaig, Catherine; Powell, Julie; Hatami, Afshin; Maari, Catherine; Le Meur, Jean-Baptiste

2018-05-01

An increase in dermatophyte infections caused by African species is reported in countries receiving African immigrants. Our goal was to determine the epidemiologic and clinical characteristics of tinea capitis in children infected with African species of dermatophytes in Montreal, Canada. Demographic and clinical data from medical records of children infected with African species of dermatophytes were retrieved retrospectively (2000-2016) at Sainte-Justine University Hospital Center. In Montreal, the number of tinea capitis cases caused by African species of dermatophytes increased sixfold over 17 years. African immigrant children (84%), men and boys (61%), and preschoolers (2-5 years old) (51%) were the most frequently affected in our 315 cases. Family contamination was frequent (45%). Referring physicians prescribed systemic antifungal treatment in 39% of cases and pediatric dermatologist consultants in 90%. Treatment failure to oral terbinafine occurred in 39% of Microsporum audouinii infections. In Montreal, there was a significant increase in tinea capitis caused by African species of dermatophytes. Microsporum audouinii is highly transmissible and often resistant to oral terbinafine. Recognizing tinea capitis trends in a given environment will improve patient care. © 2018 Wiley Periodicals, Inc.

Viral papillomatosis in Florida manatees (Trichechus manatus latirostris).

PubMed

Bossart, Gregory D; Ewing, Ruth Y; Lowe, Mark; Sweat, Mark; Decker, Susan J; Walsh, Catherine J; Ghim, Shin-je; Jenson, A Bennett

2002-02-01

The Florida manatee (Trichechus manatus latirostris) is one of the most endangered marine mammals in American coastal waters. Naturally resistant to infectious disease, the manatee immune system appears highly developed to protect it against the harsh marine environment and the effects of human-related injury. In 1997, seven captive Florida manatees developed multiple, cutaneous, pedunculated papillomas over a period of 6 months. Approximately 3 years later, four of the seven manatees developed multiple, cutaneous, sessile papillomas topically and clinically distinct from the initial lesions, some of which are still present. Histologic, ultrastructural, and immunohistochemical features indicated that the two distinct phenotypic lesions were caused by papillomaviruses (PVs). Preliminary immunologic data correlated with daily clinical observations suggested that the manatees were immunologically suppressed and that the papillomas were caused by activation of latent PV infections and reinoculation from active infections. The emergence of PV-induced papillomas in captive manatees, the possibility of activation of latent infection or transmission of active infection to free-ranging manatees, and the underlying cause of immune suppression predisposing manatees to develop viral papillomatosis are serious concerns for the future management of this highly endangered species. Copyright 2002 Elsevier Science.

Effect of major abdominal surgery on the host immune response to infection.

PubMed

Buttenschoen, Klaus; Fathimani, Kamran; Buttenschoen, Daniela Carli

2010-06-01

The present review summarizes key studies on the effects of major abdominal surgery on the host response to infection published during the last 18 months. Surgical trauma causes stereotyped systemic proinflammatory and compensatory anti-inflammatory reactions. It is leukocyte reprogramming rather than general immune suppression. The list of recent findings is long. Preoperative infectious challenge was found to increase survival. Obesity is associated with increased production of interleukin-17A in peritonitis. Abdominal surgery alters expression of toll-like receptors (TLRs). The acute phase reaction down-regulates the transcription factor carbohydrate response element binding protein. Myosin light chain kinase activation is a final pathway of acute tight junction regulation of gut barrier and zonula occludens 1 protein is an essential effector. The brain is involved in regulating the immune and gut system. Elimination of lipopolysaccharide is challenging. Th1/Th2 ratio is lowered in patients with postoperative complications. Cholinergic anti-inflammatory pathways can inhibit tissue damage. The new substance PXL01 prevents adhesions. Postoperative infection causes incisional hernias. Hypothermia reduced human leukocyte antigen DR surface expression and delayed tumor necrosis factor clearance. Systems biology identified interferon regulatory factor 3 as the negative regulator of TLR signaling. Protective immunity could contribute defeating surgical infections. Systemic inflammation is the usual response to trauma. All organs seem to be involved and linked up in cybernetic systems aiming at reconstitution of homeostasis. Although knowledge is still fragmentary, it is already difficult to integrate known facts and new technologies are required for information processing. Defining criteria to develop therapeutic strategies requires much more insight into molecular mechanisms and cybernetics of organ systems.

Antimicrobial resistance in Salmonella that caused foodborne disease outbreaks: United States, 2003–2012

PubMed Central

BROWN, A. C.; GRASS, J. E.; RICHARDSON, L. C.; NISLER, A. L.; BICKNESE, A. S.; GOULD, L. H.

2016-01-01

SUMMARY Although most non-typhoidal Salmonella illnesses are self-limiting, antimicrobial treatment is critical for invasive infections. To describe resistance in Salmonella that caused foodborne outbreaks in the United States, we linked outbreaks submitted to the Foodborne Disease Outbreak Surveillance System to isolate susceptibility data in the National Antimicrobial Resistance Monitoring System. Resistant outbreaks were defined as those linked to one or more isolates with resistance to at least one antimicrobial drug. Multidrug resistant (MDR) outbreaks had at least one isolate resistant to three or more antimicrobial classes. Twenty-one per cent (37/176) of linked outbreaks were resistant. In outbreaks attributed to a single food group, 73% (16/22) of resistant outbreaks and 46% (31/68) of non-resistant outbreaks were attributed to foods from land animals (P < 0.05). MDR Salmonella with clinically important resistance caused 29% (14/48) of outbreaks from land animals and 8% (3/40) of outbreaks from plant products (P < 0.01). In our study, resistant Salmonella infections were more common in outbreaks attributed to foods from land animals than outbreaks from foods from plants or aquatic animals. Antimicrobial susceptibility data on isolates from foodborne Salmonella outbreaks can help determine which foods are associated with resistant infections. PMID:27919296

Antimicrobial resistance in Salmonella that caused foodborne disease outbreaks: United States, 2003-2012.

PubMed

Brown, A C; Grass, J E; Richardson, L C; Nisler, A L; Bicknese, A S; Gould, L H

2017-03-01

Although most non-typhoidal Salmonella illnesses are self-limiting, antimicrobial treatment is critical for invasive infections. To describe resistance in Salmonella that caused foodborne outbreaks in the United States, we linked outbreaks submitted to the Foodborne Disease Outbreak Surveillance System to isolate susceptibility data in the National Antimicrobial Resistance Monitoring System. Resistant outbreaks were defined as those linked to one or more isolates with resistance to at least one antimicrobial drug. Multidrug resistant (MDR) outbreaks had at least one isolate resistant to three or more antimicrobial classes. Twenty-one per cent (37/176) of linked outbreaks were resistant. In outbreaks attributed to a single food group, 73% (16/22) of resistant outbreaks and 46% (31/68) of non-resistant outbreaks were attributed to foods from land animals (P < 0·05). MDR Salmonella with clinically important resistance caused 29% (14/48) of outbreaks from land animals and 8% (3/40) of outbreaks from plant products (P < 0·01). In our study, resistant Salmonella infections were more common in outbreaks attributed to foods from land animals than outbreaks from foods from plants or aquatic animals. Antimicrobial susceptibility data on isolates from foodborne Salmonella outbreaks can help determine which foods are associated with resistant infections.

[Disease concept of the slow virus infection].

PubMed

Takasu, Toshiaki

2007-08-01

This article gives a brief history of the terminology of slow virus infection, the conceptual change that occurred in it, the features common to slow infection and the current concept of slow virus infection. Björn Sigurdsson from the field of veterinary medicine proposed slow virus infection as unique mode of infection in 1954. Its initial concept was remodeled along with the general acceptance of prion theory of sheep scrapie that was proposed in 1982. The features common to slow infection include very long latency, unanimous poor prognosis, central nervous system involvement, etc. Currently the slow infection comprises those caused by slow conventional viruses that is the slow virus infection (for example subacute sclerosing panencephalitis and progressive multifocal encephalopathy in human and visna-maedi in sheep) and prion diseases (for example kuru, Creutzfeldt-Jakob disease, Gerstmann-Sträussler-Scheinker syndrome in human, scrapie and bovine spongiform encephalopathy).

Urinary tract infections in patients with type 2 diabetes mellitus: review of prevalence, diagnosis, and management

PubMed Central

Nitzan, Orna; Elias, Mazen; Chazan, Bibiana; Saliba, Walid

2015-01-01

Urinary tract infections are more common, more severe, and carry worse outcomes in patients with type 2 diabetes mellitus. They are also more often caused by resistant pathogens. Various impairments in the immune system, poor metabolic control, and incomplete bladder emptying due to autonomic neuropathy may all contribute to the enhanced risk of urinary tract infections in these patients. The new anti-diabetic sodium glucose cotransporter 2 inhibitors have not been found to significantly increase the risk of symptomatic urinary tract infections. Symptoms of urinary tract infection are similar to patients without diabetes, though some patients with diabetic neuropathy may have altered clinical signs. Treatment depends on several factors, including: presence of symptoms, severity of systemic symptoms, if infection is localized in the bladder or also involves the kidney, presence of urologic abnormalities, accompanying metabolic alterations, and renal function. There is no indication to treat diabetic patients with asymptomatic bacteriuria. Further studies are needed to improve the treatment of patients with type 2 diabetes and urinary tract infections. PMID:25759592

Management of herpesvirus infections.

PubMed

Evans, Cariad M; Kudesia, Goura; McKendrick, Mike

2013-08-01

Management of human herpesviruses remains a considerable clinical challenge, in part due to their ability to cause both lytic and latent disease. Infection with the Herpesviridae results in lifelong infection, which can reactivate at any time. Control of herpesviruses is by the innate and adaptive immune systems. Herpesviruses must evade the host innate immune system to establish infection. Once infected, the adaptive immune response, primarily CD8(+) T-cells, is crucial in establishing and maintaining latency. Latent herpesviruses are characterised by the presence of viral DNA in infected cells and limited or no viral replication. These characteristics provide a challenge to clinicians and those developing antiviral agents. The scope of this review is two-fold. First, to provide an overview of all antivirals used against herpesviruses, including their mechanism of action, pharmacokinetics, side effects, resistance and clinical uses. And second, to address the management of each of the eight herpesviruses both in the immunocompetent and immunocompromised host, providing evidence for clinical management and therapeutic options, which is important to the clinician engaged in the management of these infections. Copyright © 2013 Elsevier B.V. and the International Society of Chemotherapy. All rights reserved.

Respiratory and systemic infections in children with severe aplastic anemia on immunosuppressive therapy.

PubMed

Pawelec, Katarzyna; Salamonowicz, Malgorzata; Panasiuk, Anna; Matysiak, Michal; Demkow, Urszula

2013-01-01

In the present study we investigated the occurrence of systemic and respiratory infections in a cohort of 123 children with severe acquired aplastic anemia (SAA) on immunosuppressive therapy (IST). We recorded 101 episodes of infection in 77 patients (62.6 %). Pneumonia was among the most frequently observed clinical forms of infection (17 cases - 16.8 %). In the entire group, 23 children died, mostly in the course of fatal sepsis (15/23) and in 3 cases because of pneumonia complications. All patients were treated with horse (h-ATG) or rabbit antithymocyte globulin (r-ATG) supplemented with cyclosporine and corticosteroids. The crude incidence rate for serious infections in h-ATG group and r-ATG group was comparable. The relative risk of infectious complications was lower in patients treated with granulocyte colony stimulating factors (G-CSF) by 36 % (RR 0.64; p < 0.0001). The analysis confirmed that respiratory tract and disseminated infections comprise a very serious clinical problem and are the leading cause of death of SAA children. Active surveillance and the analysis of associated risk factors are required to detect opportunistic infections in this group of patients.

Yellow Fever 17DD Vaccine Virus Infection Causes Detectable Changes in Chicken Embryos

PubMed Central

Manso, Pedro Paulo de Abreu; Dias de Oliveira, Barbara C. E. P.; de Sequeira, Patrícia Carvalho; Maia de Souza, Yuli Rodrigues; Ferro, Jessica Maria dos Santos; da Silva, Igor José; Caputo, Luzia Fátima Gonçalves; Guedes, Priscila Tavares; dos Santos, Alexandre Araujo Cunha; Freire, Marcos da Silva; Bonaldo, Myrna Cristina; Pelajo-Machado, Marcelo

2015-01-01

The yellow fever (YF) 17D vaccine is one of the most effective human vaccines ever created. The YF vaccine has been produced since 1937 in embryonated chicken eggs inoculated with the YF 17D virus. Yet, little information is available about the infection mechanism of YF 17DD virus in this biological model. To better understand this mechanism, we infected embryos of Gallus gallus domesticus and analyzed their histopathology after 72 hours of YF infection. Some embryos showed few apoptotic bodies in infected tissues, suggesting mild focal infection processes. Confocal and super-resolution microscopic analysis allowed us to identify as targets of viral infection: skeletal muscle cells, cardiomyocytes, nervous system cells, renal tubular epithelium, lung parenchyma, and fibroblasts associated with connective tissue in the perichondrium and dermis. The virus replication was heaviest in muscle tissues. In all of these specimens, RT-PCR methods confirmed the presence of replicative intermediate and genomic YF RNA. This clearer characterization of cell targets in chicken embryos paves the way for future development of a new YF vaccine based on a new cell culture system. PMID:26371874

Yellow Fever 17DD Vaccine Virus Infection Causes Detectable Changes in Chicken Embryos.

PubMed

Manso, Pedro Paulo de Abreu; Dias de Oliveira, Barbara C E P; de Sequeira, Patrícia Carvalho; Maia de Souza, Yuli Rodrigues; Ferro, Jessica Maria dos Santos; da Silva, Igor José; Caputo, Luzia Fátima Gonçalves; Guedes, Priscila Tavares; dos Santos, Alexandre Araujo Cunha; Freire, Marcos da Silva; Bonaldo, Myrna Cristina; Pelajo-Machado, Marcelo

2015-01-01

The yellow fever (YF) 17D vaccine is one of the most effective human vaccines ever created. The YF vaccine has been produced since 1937 in embryonated chicken eggs inoculated with the YF 17D virus. Yet, little information is available about the infection mechanism of YF 17DD virus in this biological model. To better understand this mechanism, we infected embryos of Gallus gallus domesticus and analyzed their histopathology after 72 hours of YF infection. Some embryos showed few apoptotic bodies in infected tissues, suggesting mild focal infection processes. Confocal and super-resolution microscopic analysis allowed us to identify as targets of viral infection: skeletal muscle cells, cardiomyocytes, nervous system cells, renal tubular epithelium, lung parenchyma, and fibroblasts associated with connective tissue in the perichondrium and dermis. The virus replication was heaviest in muscle tissues. In all of these specimens, RT-PCR methods confirmed the presence of replicative intermediate and genomic YF RNA. This clearer characterization of cell targets in chicken embryos paves the way for future development of a new YF vaccine based on a new cell culture system.

Systems Thinking and Leadership: How Nephrologists Can Transform Dialysis Safety to Prevent Infections.

PubMed

Wong, Leslie P

2018-04-06

Infections are the second leading cause of death for patients with ESKD. Despite multiple efforts, nephrologists have been unable to prevent infections in dialysis facilities. The American Society of Nephrology and the Centers for Disease Control and Prevention have partnered to create Nephrologists Transforming Dialysis Safety to promote nephrologist leadership and engagement in efforts to "Target Zero" preventable dialysis infections. Because traditional approaches to infection control and prevention in dialysis facilities have had limited success, Nephrologists Transforming Dialysis Safety is reconceptualizing the problem in the context of the complexity of health care systems and organizational behavior. By identifying different parts of a problem and attempting to understand how these parts interact and produce a result, systems thinking has effectively tackled difficult problems in dynamic settings. The dialysis facility is composed of different physical and human elements that are interconnected and affect not only behavior but also, the existence of a culture of safety that promotes infection prevention. Because dialysis infections result from a complex system of interactions between caregivers, patients, dialysis organizations, and the environment, attempts to address infections by focusing on one element in isolation often fail. Creating a sense of urgency and commitment to eradicating dialysis infections requires leadership and motivational skills. These skills are not taught in the standard nephrology or medical director curriculum. Effective leadership by medical directors and engagement in infection prevention by nephrologists are required to create a culture of safety. It is imperative that nephrologists commit to leadership training and embrace their potential as change agents to prevent infections in dialysis facilities. This paper explores the systemic factors contributing to the ongoing dialysis infection crisis in the United States and the role of nephrologists in instilling a culture of safety in which infections can be anticipated and prevented. Copyright © 2018 by the American Society of Nephrology.

Emerging Viral Infections in Sub-Saharan Africa and the Developing Nervous System: A Mini Review.

PubMed

Kakooza-Mwesige, Angelina; Mohammed, Abdul H; Kristensson, Krister; Juliano, Sharon L; Lutwama, Julius J

2018-01-01

The global public health concern is heightened over the increasing number of emerging viruses, i.e., newly discovered or previously known that have expanded into new geographical zones. These viruses challenge the health-care systems in sub-Saharan Africa (SSA) countries from which several of them have originated and been transmitted by insects worldwide. Some of these viruses are neuroinvasive, but have been relatively neglected by neuroscientists. They may provide experiments by nature to give a time window for exposure to a new virus within sizeable, previously non-infected human populations, which, for instance, enables studies on potential long-term or late-onset effects on the developing nervous system. Here, we briefly summarize studies on the developing brain by West Nile, Zika, and Chikungunya viruses, which are mosquito-borne and have spread worldwide out of SSA. They can all be neuroinvasive, but their effects vary from malformations caused by prenatal infections to cognitive disturbances following perinatal or later infections. We also highlight Ebola virus, which can leave surviving children with psychiatric disturbances and cause persistent infections in the non-human primate brain. Greater awareness within the neuroscience community is needed to emphasize the menace evoked by these emerging viruses to the developing brain. In particular, frontline neuroscience research should include neuropediatric follow-up studies in the field on long-term or late-onset cognitive and behavior disturbances or neuropsychiatric disorders. Studies on pathogenetic mechanisms for viral-induced perturbations of brain maturation should be extended to the vulnerable periods when neurocircuit formations are at peaks during infancy and early childhood.

Emerging Viral Infections in Sub-Saharan Africa and the Developing Nervous System: A Mini Review

PubMed Central

Kakooza-Mwesige, Angelina; Mohammed, Abdul H.; Kristensson, Krister; Juliano, Sharon L.; Lutwama, Julius J.

2018-01-01

The global public health concern is heightened over the increasing number of emerging viruses, i.e., newly discovered or previously known that have expanded into new geographical zones. These viruses challenge the health-care systems in sub-Saharan Africa (SSA) countries from which several of them have originated and been transmitted by insects worldwide. Some of these viruses are neuroinvasive, but have been relatively neglected by neuroscientists. They may provide experiments by nature to give a time window for exposure to a new virus within sizeable, previously non-infected human populations, which, for instance, enables studies on potential long-term or late-onset effects on the developing nervous system. Here, we briefly summarize studies on the developing brain by West Nile, Zika, and Chikungunya viruses, which are mosquito-borne and have spread worldwide out of SSA. They can all be neuroinvasive, but their effects vary from malformations caused by prenatal infections to cognitive disturbances following perinatal or later infections. We also highlight Ebola virus, which can leave surviving children with psychiatric disturbances and cause persistent infections in the non-human primate brain. Greater awareness within the neuroscience community is needed to emphasize the menace evoked by these emerging viruses to the developing brain. In particular, frontline neuroscience research should include neuropediatric follow-up studies in the field on long-term or late-onset cognitive and behavior disturbances or neuropsychiatric disorders. Studies on pathogenetic mechanisms for viral-induced perturbations of brain maturation should be extended to the vulnerable periods when neurocircuit formations are at peaks during infancy and early childhood. PMID:29527187

Immunity to betanodavirus infections of marine fish.

PubMed

Chen, Young-Mao; Wang, Ting-Yu; Chen, Tzong-Yueh

2014-04-01

Betanodaviruses cause viral nervous necrosis in numerous fish species, but some species are resistant to infection by these viruses. It is essential to fully characterize the immune responses that underlie this protective response. Complete characterization of the immune responses against nodaviruses may allow the development of methods that stimulate fish immunity and of an effective betanodavirus vaccine. Such strategies could include stimulation of specific immune system responses or blockage of factors that decrease the immune response. The innate immune system clearly provides a front-line defense, and this includes the production of interferons and other cytokines. Interferons that are released inside infected cells and that suppress viral replication may be the most ancient form of innate immunity. This review focuses on the immune responses of fish to betanodavirus infection. Copyright © 2013 Elsevier Ltd. All rights reserved.

Infection caused by thymidine-requiring, trimethoprim-resistant bacteria.

PubMed Central

King, C H; Shlaes, D M; Dul, M J

1983-01-01

We first noted the appearance of thymidine-requiring, gram-negative bacilli in clinical specimens 2 years ago. Since then we have seen 10 patients colonized or infected with these organisms. These strains do not grow on Mueller-Hinton media, growth on MacConkey agar is variable, and growth in API 20E (Analytab Products) and Enterobacteriaceae-Plus Cards (AutoMicrobic system; Vitek Systems Inc.) is inadequate for reliable identifications. Thymidine-requiring organisms are routinely resistant to sulfonamides and trimethoprim. Infection or colonization is associated with previous sulfamethoxazole-trimethoprim therapy in most cases. Of 10 patients, 1 had septicemia of urinary tract origin, 5 had urinary tract colonization or infection, 2 had wound colonization, and two had colonization of respiratory secretions. Thymidine-requiring, gram-negative bacilli can be pathogens and present potential problems in diagnosis, identification, and susceptibility testing. PMID:6604070

Combined antifungal therapy against systemic murine infections by rare Cryptococcus species.

PubMed

Thomson, Pamela; Mayayo, Emilio; López-Fernández, Loida; Guarro, Josep; Capilla, Javier

2017-02-01

Cryptococcus albidus and Cryptococcus laurentii are uncommon species of this genus that in recent decades have increasingly caused opportunistic infections in humans, mainly in immunocompromised patients; the best therapy for such infection being unknown. Using a murine model of systemic infection by these fungi, we have evaluated the efficacy of amphotericin B (AMB) at 0.8 mg/kg, administered intravenously, fluconazole (FLC) or voriconazole (VRC), both administered orally, at 25 mg/kg and the combination of AMB plus VRC against three C. albidus and two C. laurentii strains. All the treatments significantly reduced the fungal burden in all the organs studied. The combination showed a synergistic effect in the reduction in fungal load, working better than both monotherapies. The histopathological study confirmed the efficacy of the treatments. © 2016 Blackwell Verlag GmbH.

Gonococcal cellulitis: an (un)friendly bite.

PubMed

Lal, Amos; Rapose, Alwyn

2018-03-16

Gonococcal infection can present with wide spectrum of symptoms, most commonly involving the genitals. This case highlights a rare presentation of Neisseria gonorrhoeae infection primarily with skin involvement without uro-genital disease. A 33-year-old male was admitted to the hospital with complaints of painful swelling of his penis. In the emergency room, he underwent incision and drainage of the abscess under local anaesthesia. After microbiological evaluation, he was found to have skin abscess caused by N. gonorrhoeae and was treated with intravenous ceftriaxone and changed to oral agent amoxicillin-clavulanate with complete resolution. The manifestations of gonococcal infection have changed significantly over the last few years, with more involvement of extra genital sites attributed to changes in sexual practices. Our patient was treated for cellulitis and abscess caused by N. gonorrhoeae in the absence of systemic or urethral disease. Recommendations regarding treatment of gonococcal infection have been widely published. However, there is a paucity of evidence-based guidelines regarding the therapy of primary cutaneous gonococcal infection. Pooled data from similar cases may help determine the optimum therapy.

Genital herpes simplex virus infections.

PubMed

Rosenthal, M S

1979-09-01

In recent years, a great increase in interest in genital herpes has been stimulated partly by the rising prevalence of this disease and partly by observations suggesting that genital herpes is a cause of cervical cancer. The clinical pictures produced by genital herpes simplex virus infections are similar in men and women. In contrast to recurrent attacks, initial episodes of infection are generally more extensive, last longer, and are more often associated with regional lymphadenopathy and systemic symptoms. Genital herpes in pregnancy may pose a serious threat to the newborn infant. Although the data suggesting genital herpes simplex virus infection is a cause of cervical cancer are quite extensive, the evidence is largely circumstantial. In spite of these more serious aspects of genital herpes simplex virus infection, episodes of genital herpes are almost always self-limited and benign. Frequent recurrences pose the major therapeutic and management problem. At present, there is no satisfactory treatment for recurrent genital herpes simplex virus in fection. Many of the suggested therapies, although some sound very promising, are potentially dangerous and should be used only under carefully controlled conditions.

Causes and predictors of mortality in hospitalized lupus patient in Sarawak General Hospital, Malaysia.

PubMed

Teh, C L; Ling, G R

2013-01-01

Systemic lupus erythematosus (SLE) is a serious autoimmune disease that can be life threatening and fatal if left untreated. Causes and prognostic indicators of death in SLE have been well studied in developed countries but lacking in developing countries. We aimed to investigate the causes of mortality in hospitalized patients with SLE and determine the prognostic indicators of mortality during hospitalization in our center. All SLE patients who were admitted to Sarawak General Hospital from January 1, 2006 to December 31, 2010, were followed up in a prospective study using a standard protocol. Demographic data, clinical features, disease activities and damage indices were collected. Logistic regression and Cox regression analysis were used to determine the prognostic indicators of mortality in our patients. There were a total of 251 patients in our study, with the female to male ratio 10 to 1. Our study patients were of multiethnic origins. They had a mean age of 30.5 ± 12.2 years and a mean duration of illness of 36.5 ± 51.6 months. The main involvements were hematologic (73.3%), renal (70.9%) and mucocutaneous (67.3%). There were 26 deaths (10.4%), with the main causes being: infection and flare (50%), infection alone (19%), flare alone (19%) and others (12%). Independent predictors of mortality in our cohort of SLE patients were the presence of both infection and flare of disease (hazard ratio (HR) 5.56) and high damage indices at the time of admission (HR 1.91). Infection and flare were the main causes of death in hospitalized Asian patients with SLE. The presence of infection with flare and high damage indices at the time of admission were independent prognostic indicators of mortality.

Latent Microsporidiosis Caused by Encephalitozoon cuniculi in Immunocompetent Hosts: A Murine Model Demonstrating the Ineffectiveness of the Immune System and Treatment with Albendazole

PubMed Central

Kotkova, Michaela; Sak, Bohumil; Kvetonova, Dana; Kvac, Martin

2013-01-01

Background Microsporidia are obligate intracellular parasites causing severe infections with lethal outcome in immunocompromised hosts. However, these pathogens are more frequently reported as latent infections in immunocompetent individuals and raises questions about the potential risk of reactivation following induced immunosuppression. Aims To evaluate the possibility latent microsporidiosis, efficacy or albendazole, and reactivation, the authors monitored the course of E. cuniculi infection in immunocompetent BALB/c mice and immunodeficient SCID mice using molecular methods. Methods Mice were per orally infected with 107 spores of E. cuniculi. Selected groups were treated with albendazole, re-infected or chemically immunosuppressed by dexamethasone. The presence of microsporidia in the host’s organs and feces were determined using PCR methods. Changes in numbers of lymphocytes in blood and in spleen after induction of immunosuppression were confirmed using flow cytometry analysis. Results Whereas E. cuniculi caused lethal microsporidiosis in SCID mice, the infection in BABL/c mice remained asymptomatic despite parasite dissemination into many organs during the acute infection phase. Albendazole treatment led to microsporidia elimination from organs in BALB/c mice. In SCID mice, however, only a temporary reduction in number of affected organs was observed and infection re-established post-treatment. Dexamethasone treatment resulted in a chronic microsporidia infection disseminating into most organs in BALB/c mice. Although the presence of E. cuniculi in organs of albendazole- treated mice was undetectable by PCR, it was striking that infection was reactivated by immunosuppression treatment. Conclusion Our results demonstrated that microsporidia can successfully survive in organs of immunocompetent hosts and are able to reactivate from undetectable levels and spread within these hosts after induction of immunosuppression. These findings stress the danger of latent microsporidiosis as a life-threatening risk factor especially for individuals undergoing chemotherapy and in transplant recipients of organs originating from infected donors. PMID:23593356

Quantifying the Evolutionary Conservation of Genes Encoding Multidrug Efflux Pumps in the ESKAPE Pathogens To Identify Antimicrobial Drug Targets.

PubMed

Brooks, Lauren E; Ul-Hasan, Sabah; Chan, Benjamin K; Sistrom, Mark J

2018-01-01

Increasing rates of antibiotic-resistant bacterial infection are one of the most pressing contemporary global health concerns. The ESKAPE pathogens (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter species) have been identified as the leading global cause of multidrug-resistant bacterial infections, and overexpression of multidrug efflux (MEX) transport systems has been identified as one of the most critical mechanisms facilitating the evolution of multidrug resistance in ESKAPE pathogens. Despite efforts to develop efflux pump inhibitors to combat antibiotic resistance, the need persists to identify additional targets for future investigations. We evaluated evolutionary pressures on 110 MEX-encoding genes from all annotated ESKAPE organism genomes. We identify several MEX genes under stabilizing selection-representing targets which can facilitate broad-spectrum treatments with evolutionary constraints limiting the potential emergence of escape mutants. We also examine MEX systems being evaluated as drug targets, demonstrating that divergent selection may underlie some of the problems encountered in the development of effective treatments-specifically in relation to the NorA system in S. aureus. This study provides a comprehensive evolutionary context to efflux in the ESKAPE pathogens, which will provide critical context to the evaluation of efflux systems as antibiotic targets. IMPORTANCE Increasing rates of antibiotic-resistant bacterial infection are one of the most pressing contemporary global health concerns. The ESKAPE pathogen group represents the leading cause of these infections, and upregulation of efflux pump expression is a significant mechanism of resistance in these pathogens. This has resulted in substantial interest in the development of efflux pump inhibitors to combat antibiotic-resistant infections; however, no widespread treatments have been developed to date. Our study evaluates an often-underappreciated aspect of resistance-the impact of evolutionary selection. We evaluate selection on all annotated efflux genes in all sequenced ESKAPE pathogens, providing critical context for and insight into current and future development of efflux-targeting treatments for resistant bacterial infections.

Quantifying the Evolutionary Conservation of Genes Encoding Multidrug Efflux Pumps in the ESKAPE Pathogens To Identify Antimicrobial Drug Targets

PubMed Central

Ul-Hasan, Sabah; Chan, Benjamin K.; Sistrom, Mark J.

2018-01-01

ABSTRACT Increasing rates of antibiotic-resistant bacterial infection are one of the most pressing contemporary global health concerns. The ESKAPE pathogens (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter species) have been identified as the leading global cause of multidrug-resistant bacterial infections, and overexpression of multidrug efflux (MEX) transport systems has been identified as one of the most critical mechanisms facilitating the evolution of multidrug resistance in ESKAPE pathogens. Despite efforts to develop efflux pump inhibitors to combat antibiotic resistance, the need persists to identify additional targets for future investigations. We evaluated evolutionary pressures on 110 MEX-encoding genes from all annotated ESKAPE organism genomes. We identify several MEX genes under stabilizing selection—representing targets which can facilitate broad-spectrum treatments with evolutionary constraints limiting the potential emergence of escape mutants. We also examine MEX systems being evaluated as drug targets, demonstrating that divergent selection may underlie some of the problems encountered in the development of effective treatments—specifically in relation to the NorA system in S. aureus. This study provides a comprehensive evolutionary context to efflux in the ESKAPE pathogens, which will provide critical context to the evaluation of efflux systems as antibiotic targets. IMPORTANCE Increasing rates of antibiotic-resistant bacterial infection are one of the most pressing contemporary global health concerns. The ESKAPE pathogen group represents the leading cause of these infections, and upregulation of efflux pump expression is a significant mechanism of resistance in these pathogens. This has resulted in substantial interest in the development of efflux pump inhibitors to combat antibiotic-resistant infections; however, no widespread treatments have been developed to date. Our study evaluates an often-underappreciated aspect of resistance—the impact of evolutionary selection. We evaluate selection on all annotated efflux genes in all sequenced ESKAPE pathogens, providing critical context for and insight into current and future development of efflux-targeting treatments for resistant bacterial infections. PMID:29719870

[Bladder rupture caused by spontaneous perforation of an infected urachal cyst].

PubMed

Maruschke, M; Kreutzer, H J; Seiter, H

2003-06-01

Anomalies of the fetal urachus are rare. Normally, the postnatal urachus presents as a fibrous band extending from the bladder to the umbilicus. Urachal cysts may occur in postnatal life. Spontaneous perforation of urachal cysts is a very rare condition, which clinically may not be distinguishable from other acute abdominal conditions. We report a case of a 63-year-old male with a history of recurrent urinary tract infections and a bladder rupture caused by a spontaneous perforation of an infected urachal cyst. The symptomatology showed abdominal rigidity and pain, a palpable mass in the lower abdomen, and hematuria. Laboratory findings showed leukocytosis and an increased CRP level. The bladder rupture was confirmed by cystography. Bacteriologic examination identified Proteus vulgaris, Corynebacterium species, and Klebsiella pneumoniae. Most of the published cases in the literature report about intraperitoneal perforation of infected urachal cysts. In the present case, we found a spontaneous perforation of an infected urachal cyst leading to an extraperitoneal bladder rupture with an extraperitoneal limitation of the infection. The definitive therapy was complete surgical excision including a cuff of the bladder, drainage, and systemic broad-spectrum and local application of antibiotics. The further course was uneventful.

Multiple Ceratocystis smalleyi infections associated with reduced stem water transport in bitternut hickory.

PubMed

Park, J-H; Juzwik, J; Cavender-Bares, J

2013-06-01

Hundreds of cankers caused by Ceratocystis smalleyi are associated with hickory bark beetle-attacked bitternut hickory exhibiting rapid crown decline in the north-central and northeastern United States. Discolored sapwood colonized by the fungus commonly underlies the cankers. Field studies were conducted to test the hypothesis that C. smalleyi infections cause vascular system dysfunction in infected trees. Fifty C. smalleyi inoculations made at 1.8 to 3.8 m in height on stems of healthy bitternut hickory trees (13 to 28 cm in diameter at 1.4 m in height) resulted in extensive canker formation and sapwood discoloration 12 to 14 months after treatment compared with water-inoculated and noninoculated controls. Sap flow velocity (midday) was significantly lower in the infected trees compared with that in the controls. Sap flow velocity also was inversely correlated with the proportion of bark area with cankered tissues and with tylose abundance in the youngest two growth rings. Tylose formation in current-year vessels associated with C. smalleyi infections is likely responsible for much of the water transport disruption. It is hypothesized that multiple stem infections of C. smalleyi and the resulting xylem dysfunction contribute to crown wilt development in bitternut hickory exhibiting rapid crown decline.

Genetic battle between Helicobacter pylori and humans. The mechanism underlying homologous recombination in bacteria, which can infect human cells.

PubMed

Hanada, Katsuhiro; Yamaoka, Yoshio

2014-10-01

Helicobacter pylori is a gram-negative pathogenic bacterium that colonises the human stomach. The chronic infection it causes results in peptic ulcers and gastric cancers. H. pylori can easily establish a chronic infection even if the immune system attacks this pathogen with oxidative stress agents and immunoglobulins. This is attributed to bacterial defence mechanisms against these stresses. As a defence mechanism against oxidative stresses, in bacterial genomes, homologous recombination can act as a repair pathway of DNA's double-strand breaks (DSBs). Moreover, homologous recombination is also involved in the antigenic variation in H. pylori. Gene conversion alters genomic structures of babA and babB (encoding outer membrane proteins), resulting in escape from immunoglobulin attacks. Thus, homologous recombination in bacteria plays an important role in the maintenance of a chronic infection. In addition, H. pylori infection causes DSBs in human cells. Homologous recombination is also involved in the repair of DSBs in human cells. In this review, we describe the roles of homologous recombination with an emphasis on the maintenance of a chronic infection. Copyright © 2014 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.

Distinct mortality profile in systemic sclerosis: a death certificate study in Rio de Janeiro, Brazil (2006-2015) using a multiple causes of death analysis.

PubMed

de Rezende, Rodrigo Poubel Vieira; Gismondi, Ronaldo Altenburg; Maleh, Haim Cesar; de Miranda Coelho, Elisa Mendes; Vieira, Carol Sartori; Rosa, Maria Luiza Garcia; Mocarzel, Luis Otavio

2017-12-16

The objective of this study was to assess the mortality profile related to SSc in the state of Rio de Janeiro, Brazil. We retrospectively examined all registered deaths in the region (2006-2015 period) in which the diagnosis of SSc was mentioned on any line of the death certificates (underlying cause of death [UCD], n = 223; non-UCD, n = 151). Besides the analysis of gender, age, and the causes of death, we also compared the mortality from UCDs between individuals whose death causes included SSc (cases) and those whose death causes did not include SSc (deceased controls). For the latter comparison, we used the mortality odds ratio to approximate the cause-specific standardized mortality ratio. We identified 1495 death causes among the 374 SSc cases. The mean age at death of the SSc cases (85% women) was significantly lower than that of the controls (n = 1,294,117) (58.7 vs. 65.5 years, respectively). The main death causes were circulatory system diseases, infections, and respiratory diseases (36%, 34%, and 21% of SSc cases, respectively). Compared to the deceased controls, there were proportionally more deaths among the SSc cases from pulmonary arterial hypertension, lung fibrosis, septicemia, gastrointestinal hemorrhage, other systemic connective tissue diseases, and heart failure (for death age < 50 years). We confirmed the high burden of cardiovascular, respiratory, and infectious causes in this predominantly non-Caucasian sample of SSc patients. Of interest, the percentage of infection-related deaths in our report was about three times higher than that in SSc studies with predominantly Caucasian populations.

Infections Caused by Scedosporium spp.

PubMed Central

Cortez, Karoll J.; Roilides, Emmanuel; Quiroz-Telles, Flavio; Meletiadis, Joseph; Antachopoulos, Charalampos; Knudsen, Tena; Buchanan, Wendy; Milanovich, Jeffrey; Sutton, Deanna A.; Fothergill, Annette; Rinaldi, Michael G.; Shea, Yvonne R.; Zaoutis, Theoklis; Kottilil, Shyam; Walsh, Thomas J.

2008-01-01

Scedosporium spp. are increasingly recognized as causes of resistant life-threatening infections in immunocompromised patients. Scedosporium spp. also cause a wide spectrum of conditions, including mycetoma, saprobic involvement and colonization of the airways, sinopulmonary infections, extrapulmonary localized infections, and disseminated infections. Invasive scedosporium infections are also associated with central nervous infection following near-drowning accidents. The most common sites of infection are the lungs, sinuses, bones, joints, eyes, and brain. Scedosporium apiospermum and Scedosporium prolificans are the two principal medically important species of this genus. Pseudallescheria boydii, the teleomorph of S. apiospermum, is recognized by the presence of cleistothecia. Recent advances in molecular taxonomy have advanced the understanding of the genus Scedosporium and have demonstrated a wider range of species than heretofore recognized. Studies of the pathogenesis of and immune response to Scedosporium spp. underscore the importance of innate host defenses in protection against these organisms. Microbiological diagnosis of Scedosporium spp. currently depends upon culture and morphological characterization. Molecular tools for clinical microbiological detection of Scedosporium spp. are currently investigational. Infections caused by S. apiospermum and P. boydii in patients and animals may respond to antifungal triazoles. By comparison, infections caused by S. prolificans seldom respond to medical therapy alone. Surgery and reversal of immunosuppression may be the only effective therapeutic options for infections caused by S. prolificans. PMID:18202441

Infections caused by Scedosporium spp.

PubMed

Cortez, Karoll J; Roilides, Emmanuel; Quiroz-Telles, Flavio; Meletiadis, Joseph; Antachopoulos, Charalampos; Knudsen, Tena; Buchanan, Wendy; Milanovich, Jeffrey; Sutton, Deanna A; Fothergill, Annette; Rinaldi, Michael G; Shea, Yvonne R; Zaoutis, Theoklis; Kottilil, Shyam; Walsh, Thomas J

2008-01-01

Scedosporium spp. are increasingly recognized as causes of resistant life-threatening infections in immunocompromised patients. Scedosporium spp. also cause a wide spectrum of conditions, including mycetoma, saprobic involvement and colonization of the airways, sinopulmonary infections, extrapulmonary localized infections, and disseminated infections. Invasive scedosporium infections are also associated with central nervous infection following near-drowning accidents. The most common sites of infection are the lungs, sinuses, bones, joints, eyes, and brain. Scedosporium apiospermum and Scedosporium prolificans are the two principal medically important species of this genus. Pseudallescheria boydii, the teleomorph of S. apiospermum, is recognized by the presence of cleistothecia. Recent advances in molecular taxonomy have advanced the understanding of the genus Scedosporium and have demonstrated a wider range of species than heretofore recognized. Studies of the pathogenesis of and immune response to Scedosporium spp. underscore the importance of innate host defenses in protection against these organisms. Microbiological diagnosis of Scedosporium spp. currently depends upon culture and morphological characterization. Molecular tools for clinical microbiological detection of Scedosporium spp. are currently investigational. Infections caused by S. apiospermum and P. boydii in patients and animals may respond to antifungal triazoles. By comparison, infections caused by S. prolificans seldom respond to medical therapy alone. Surgery and reversal of immunosuppression may be the only effective therapeutic options for infections caused by S. prolificans.

Tioman virus infection in experimentally infected mouse brain and its association with apoptosis.

PubMed

Yaiw, Koon Chu; Ong, Kien Chai; Chua, Kaw Bing; Bingham, John; Wang, Linfa; Shamala, Devi; Wong, Kum Thong

2007-08-01

Tioman virus is a newly described bat-urine derived paramyxovirus isolated in Tioman Island, Malaysia in 2001. Hitherto, neither human nor animal infection by this virus has been reported. Nonetheless, its close relationship to another paramyxovirus, the Menangle virus which had caused diseases in humans and pigs [Philbey, A.W., Kirkland, P.D., Ross, A.D., Davis, R.J., Gleeson, A.B., Love, R.J., Daniels, P.W., Gould, A.R., Hyatt, A.D., 1998. An apparently new virus (family Paramyxoviridae) infectious for pigs, humans, and fruit bats. Emerg. Infect. Dis. 4, 269-271], raises the possibility that it may be potentially pathogenic. In this study, mice were experimentally infected with Tioman virus by intraperitoneal and intracerebral routes, and the cellular targets and topographical distribution of viral genome and antigens were examined using in situ hybridization and immunohistochemistry, respectively. The possible association between viral infection and apoptosis was also investigated using the TUNEL assay and immunohistochemistry to FasL, Caspase-3, Caspase-8, Caspase-9 and bcl-2. The results showed that Tioman virus inoculated intracerebrally was neurotropic causing plaque-like necrotic areas, and appeared to preferentially replicate in the neocortex and limbic system. Viral infection of inflammatory cells was also demonstrated. TUNEL and Caspase-3 positivity was found in inflammatory cells but not in neurons, while FasL, Caspase-8 and Caspase-9 were consistently negative. This suggests that neuronal infection was associated with necrosis rather than apoptosis. Moreover, the data suggest that there may be an association between viral infection and apoptosis in inflammatory cells, and that it could, at least in part, involve Caspase-independent pathways. Bcl-2 was expressed in some neurons and inflammatory cells indicating its possible role in anti-apoptosis. There was no evidence of central nervous system infection via the intraperitoneal route.

Bilateral lenticular Encephalitozoon cuniculi infection in a snow leopard (Panthera uncia).

PubMed

Scurrell, Emma Jane; Holding, Ellen; Hopper, Jane; Denk, Daniela; Fuchs-Baumgartinger, Andrea; Silbermayr, Katja; Nell, Barbara

2015-01-01

Bilateral phacoclastic uveitis caused by lenticular infection with Encephalitozoon cuniculi is described in a snow leopard. The diagnosis was made on histopathological and immunohistological examination of both eyes submitted after postmortem examination. There was a positive antibody titer for E. cuniculi (1:320). Polymerase chain reaction (PCR) and sequence analysis of formalin-fixed, paraffin-embedded ocular tissue detected the DNA of E. cuniculi, strain III. No other systemic lesions attributable to the E. cuniculi infection were identified. © 2014 American College of Veterinary Ophthalmologists.

Pasteurella multocida meningitis in an adult: case report.

PubMed

Armstrong, G R; Sen, R A; Wilkinson, J

2000-03-01

Pasteurella multocida is known to form part of the normal flora in the nasopharynx or gastrointestinal tract in many domestic and wild animals. Most human P multocida infections are soft tissue infections caused by dog or cat bites. Less commonly this bacterium is associated with infections affecting other organ systems of man. A case of fatal P multocida meningitis discovered at the necropsy of a 52 year old man is described. P multocida is an unusual causative agent of meningitis which tends to affect those at the extremes of age.

[Infectious risk related to the formation of multi-species biofilms (Candida - bacteria) on peripheral vascular catheters].

PubMed

Seghir, A; Boucherit-Otmani, Z; Sari-Belkharroubi, L; Boucherit, K

2017-03-01

The Candida yeasts are the fourth leading cause of death from systemic infections, the risk may increase when the infection also involves bacteria. Yeasts and bacteria can adhere to medical implants, such as peripheral vascular catheters, and form a multicellular structures called "mixed biofilms" more resistant to antimicrobials agents. However, the formation of mixed biofilms on implants leads to long-term persistent infections because they can act as reservoirs of pathogens that have poorly understood interactions. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

Disseminated sporotrichosis

PubMed Central

Romero-Cabello, Raúl; Bonifaz, Alexandro; Romero-Feregrino, Raúl; Sánchez, Carlos Javier; Linares, Yancy; Zavala, Jorge Tay; Romero, Leticia Calderón; Romero-Feregrino, Rodrigo; Vega, José T Sánchez

2011-01-01

Sporotrichosis is a subacute or chronic infection caused by Sporothrix schenckii. It is a primary cutaneous infection and it has different clinical forms: disseminated by lymphatic vessels (75%), localised cutaneous form (20%), disseminated cutaneous and extracuteus rarely. The systemic disseminated sporotrichosis is considered a severe opportunistic infection. The best diagnostic test is the culture. The authors report a case of a 36-year-old man, originally from Puebla, Mexico, with a diagnosis of disseminated sporotrichosis. Differential diagnosis with other pathologies includes leishmaniasis, chromoblastomycosis, tuberculosis verrucose and lymphangitis. The development of unusual presentations in immunocompromised patients has been reported. PMID:22700076

Hospital water and opportunities for infection prevention

PubMed Central

Decker, Brooke K.; Palmore, Tara N.

2017-01-01

Nosocomial waterborne pathogens may reach patients through several modes of transmission. Colonization of healthcare facility waterworks can occur in the proximal infrastructure, in the distal water outlets, or both. Infections with waterborne organisms such as Legionella, mycobacteria, Pseudomonas, and others cause significant morbidity and mortality, particularly in immunocomprised patients. Hospitals should have prospective water safety plans that include preventive measures, as prevention is preferable to remediation of contaminated hospital water distribution system. Whole genome sequencing may provide more informative epidemiologic data to link patient infections with hospital water isolates. PMID:25217106

Multiple cortical brain abscesses due to Listeria monocytogenes in an immunocompetent patient.

PubMed

Khan, Sadia; Kumar, Anil; Kale, Satyajit; Kurkure, Nitin; Nair, Gulsiv; Dinesh, Kavitha

2018-04-01

Listeria monocytogenes is an intracellular organism which is well recognised for its ability to cause meningeal infections in neonates, immunosuppressed, debilitated and elderly individuals. 1 Other less common central nervous system (CNS) infections caused by Listeria spp. include rhomboencephalitis, cerebritis and abscesses in the brain, brain stem and spinal cord. The neuroradiological appearance of Listeria brain abscesses is similar to other types and may also mimic primary or metastatic brain tumours. 2 , 3 We report a case of Listeria brain abscesses in a patient who was being treated for atypical parkinsonism. A good clinical outcome was achieved after appropriate antimicrobial therapy.

A rare disease mimics postoperative bile leakage: Invasive aspergillosis.

PubMed

Yazar, Fatih Mehmet; Urfalıoğlu, Aykut; Boran, Ömer Faruk; Sayar, Hamide; Kanat, Burhan Hakan; Emre, Arif; Cengiz, Emrah; Bülbüloğlu, Ertan

2016-09-01

Aspergillus fungi can cause serious infections, including intra-abdominal infection, particularly in patients with compromised immune system. Described in the present report is case of 46-year-old female patient who had undergone laparoscopic cholecystectomy (LC) at another healthcare facility. In early postoperative period, she had increasing complaints of swelling, nausea, and vomiting. On postoperative 19th day, she was referred to our clinic with diagnosis of acute abdomen. Surgery was performed with suspected possibility of bile leakage. However, pathological examination of soft, yellow-green mass found in subhepatic space determined it was fungus ball caused by fungi of the genus Aspergillus. Patient was diagnosed postoperative intra-abdominal aspergillosis (IAA).

Influenza-Omics and the Host Response: Recent Advances and Future Prospects

PubMed Central

Powell, Joshua D.; Waters, Katrina M.

2017-01-01

Influenza A viruses (IAV) continually evolve and have the capacity to cause global pandemics. Because IAV represents an ongoing threat, identifying novel therapies and host innate immune factors that contribute to IAV pathogenesis is of considerable interest. This review summarizes the relevant literature as it relates to global host responses to influenza infection at both the proteome and transcriptome level. The various-omics infection systems that include but are not limited to ferrets, mice, pigs, and even the controlled infection of humans are reviewed. Discussion focuses on recent advances, remaining challenges, and knowledge gaps as it relates to influenza-omics infection outcomes. PMID:28604586

Increased Hospitalizations for Neuropathies as Indicators of Zika Virus Infection, according to Health Information System Data, Brazil.

PubMed

Barcellos, Christovam; Xavier, Diego Ricardo; Pavão, Ana Luiza; Boccolini, Cristiano Siqueira; Pina, Maria Fatima; Pedroso, Marcel; Romero, Dalia; Romão, Anselmo Rocha

2016-11-01

Evidence is increasing that Zika virus can cause extensive damage to the central nervous system, affecting both fetuses and adults. We sought to identify traces of possible clinical manifestations of nervous system diseases among the registers of hospital admissions recorded in the Brazilian Unified Health System. Time series of several diagnoses from the International Classification of Diseases, 10th Revision, were analyzed by using control diagrams, during January 2008-February 2016. Beginning in mid-2014, we observed an unprecedented and significant rise in the hospitalization rate for congenital malformations of the nervous system, Guillain-Barré syndrome, encephalitis, myelitis, and encephalomyelitis. These conditions are compatible with viral infection and inflammation-associated manifestations and may have been due to the entrance of Zika virus into Brazil. These findings show the necessity of adequately diagnosing and treating suspected cases of Zika virus infection and also that health surveillance systems can be improved by using routine data.

Simulating an Infection Growth Model in Certain Healthy Metabolic Pathways of Homo sapiens for Highlighting Their Role in Type I Diabetes mellitus Using Fire-Spread Strategy, Feedbacks and Sensitivities

PubMed Central

Tagore, Somnath; De, Rajat K.

2013-01-01

Disease Systems Biology is an area of life sciences, which is not very well understood to date. Analyzing infections and their spread in healthy metabolite networks can be one of the focussed areas in this regard. We have proposed a theory based on the classical forest fire model for analyzing the path of infection spread in healthy metabolic pathways. The theory suggests that when fire erupts in a forest, it spreads, and the surrounding trees also catch fire. Similarly, when we consider a metabolic network, the infection caused in the metabolites of the network spreads like a fire. We have constructed a simulation model which is used to study the infection caused in the metabolic networks from the start of infection, to spread and ultimately combating it. For implementation, we have used two approaches, first, based on quantitative strategies using ordinary differential equations and second, using graph-theory based properties. Furthermore, we are using certain probabilistic scores to complete this task and for interpreting the harm caused in the network, given by a ‘critical value’ to check whether the infection can be cured or not. We have tested our simulation model on metabolic pathways involved in Type I Diabetes mellitus in Homo sapiens. For validating our results biologically, we have used sensitivity analysis, both local and global, as well as for identifying the role of feedbacks in spreading infection in metabolic pathways. Moreover, information in literature has also been used to validate the results. The metabolic network datasets have been collected from the Kyoto Encyclopedia of Genes and Genomes (KEGG). PMID:24039701

ECCMID 2016: addressing the burden of recurrent Clostridium difficile infections.

PubMed

Eckmann, Christian; Lyon, Sue

2016-10-01

26th European Congress of Clinical Microbiology and Infectious Diseases (ECCMID), 9-12th April 2016, Amsterdam, The Netherlands The European Congress of Clinical Microbiology and Infectious Diseases (ECCMID) is the annual scientific meeting of the European Society of Clinical Microbiology. ECCMID 2016, held in Amsterdam, The Netherlands, was attended by over 11,600 clinical microbiologists and infectious disease physicians from more than 120 countries. The Congress offered an essential opportunity to learn more about the diagnosis, prevention and treatment of healthcare-associated infections, especially those caused by Clostridium difficile. Recurrent C. difficile infections have an especially serious adverse impact on patients, their families and healthcare systems across Europe and around the world, and continue to be a cause for concern among ECCMID delegates and their colleagues responsible for managing vulnerable patients in acute hospitals and other healthcare facilities.

A Rare Presentation of Cranial Polyneuropathy Without Rash Caused by Varicella Zoster Virus

PubMed Central

Tecellioglu, Mehmet; Kamisli, Suat; Erbay, Mehmet Fatih; Kamisli, Ozden; Ozcan, Cemal

2017-01-01

Introduction: Varicella Zoster Virus (VZV) is associated with many disorders of the central and peripheral nervous systems including neuralgia, meningitis, meningoencephalitis, cerebellitis, vasculopathy, myelopathy, Ramsay-Hunt syndrome, and polyneuritis cranialis. Cranial nerves V, VI, VII, VIII, IX, X, XI, and/or XII may be affected. The neurological disorders caused by VZV usually present with rash, but may rarely present without rash. Case report: We herein present a case of polyneuritis cranialis without rash caused by VZV affecting cranial nerves VII, VIII, IX, and X. After excluding other causes of the condition, we diagnosed VZV infection based on VZV DNA in the CSF and an elevated anti-VZV IgG level in serum. The patient responded well to antiviral therapy. Conclusion: VZV infection should be kept in mind during the differential diagnosis of polyneuritis cranialis; it is important to note that VZV re-activation may occur without rash. PMID:28974853

Cryptococcus neoformans and Cryptococcus gattii, the Etiologic Agents of Cryptococcosis

PubMed Central

Kwon-Chung, Kyung J.; Fraser, James A.; Doering, Tamara L.; Wang, Zhou; Janbon, Guilhem; Idnurm, Alexander; Bahn, Yong-Sun

2014-01-01

Cryptococcus neoformans and Cryptococcus gattii are the two etiologic agents of cryptococcosis. They belong to the phylum Basidiomycota and can be readily distinguished from other pathogenic yeasts such as Candida by the presence of a polysaccharide capsule, formation of melanin, and urease activity, which all function as virulence determinants. Infection proceeds via inhalation and subsequent dissemination to the central nervous system to cause meningoencephalitis. The most common risk for cryptococcosis caused by C. neoformans is AIDS, whereas infections caused by C. gattii are more often reported in immunocompetent patients with undefined risk than in the immunocompromised. There have been many chapters, reviews, and books written on C. neoformans. The topics we focus on in this article include species description, pathogenesis, life cycle, capsule, and stress response, which serve to highlight the specializations in virulence that have occurred in this unique encapsulated melanin-forming yeast that causes global deaths estimated at more than 600,000 annually. PMID:24985132

Pseudallescheria boydii brain abscess in a renal transplant recipient: first case report in Southeast Asia.

PubMed

Satirapoj, B; Ruangkanchanasetr, P; Treewatchareekorn, S; Supasyndh, O; Luesutthiviboon, L; Supaporn, T

2008-09-01

Pseudallescheria boydii and its asexual form, Scedosporium apiospermum, are ubiquitous filamentous fungi that rarely cause central nervous system (CNS) infection. Brain abscess caused by P. boydii is a highly lethal infection, usually seen in organ transplant recipients who receive a number of immunosuppressive agents. We have presented a case of a 48-year-old man 6 years after renal transplantation who received methylprednisolone followed by antithymocyte globulin for treatment of acute cellular rejection. Eight weeks later, he developed fever, headache, and left-sided hemiparesis. Further investigation with magnetic resonance imaging of the brain showed multiple ring-enhancing hypodense lesions with marked edema which were compatible with brain abscesses. Following surgical drainage, multiple fungal elements were initially described as Aspergillus species. The patient failed to improve and died from rapidly progressive infection despite treatment with amphotericin B. Later a diagnosis was finally made by the isolation of P. boydii in pus culture. The specific diagnosis is difficult to rapidly make, because P. boydii mimics other fungi morphologically in tissue sections and may produce infections clinically similar to other mycoses. Culture of the organism is required for definitive diagnosis. P. boydii infections are important complications of transplantation. They are difficult to treat due to resistance to amphotericin B. Physicians should consider P. boydii a possible cause of brain abscess in organ transplant recipients, especially with heavy immunosuppressive agents. This is the first case report of CNS infection due to P. boydii in a renal transplant patient in Southeast Asia.

Causes of acute bronchitis (image)

MedlinePlus

... of the bronchial tubes, the part of the respiratory system that leads into the lungs. Acute bronchitis has a sudden onset and usually appears after a respiratory infection, such as a cold, and can be ...

Organic Causes of Weight Gain and Obesity

MedlinePlus

... Life Family Life Family Life Medical Home Family Dynamics Media Work & Play Getting Involved in Your Community ... and Urinary Tract Glands & Growth Head Neck & Nervous System Heart Infections Learning Disabilities Obesity Orthopedic Prevention Sexually ...

Dengue viruses – an overview

PubMed Central

Bäck, Anne Tuiskunen; Lundkvist, Åke

2013-01-01

Dengue viruses (DENVs) cause the most common arthropod-borne viral disease in man with 50–100 million infections per year. Because of the lack of a vaccine and antiviral drugs, the sole measure of control is limiting the Aedes mosquito vectors. DENV infection can be asymptomatic or a self-limited, acute febrile disease ranging in severity. The classical form of dengue fever (DF) is characterized by high fever, headache, stomach ache, rash, myalgia, and arthralgia. Severe dengue, dengue hemorrhagic fever (DHF), and dengue shock syndrome (DSS) are accompanied by thrombocytopenia, vascular leakage, and hypotension. DSS, which can be fatal, is characterized by systemic shock. Despite intensive research, the underlying mechanisms causing severe dengue is still not well understood partly due to the lack of appropriate animal models of infection and disease. However, even though it is clear that both viral and host factors play important roles in the course of infection, a fundamental knowledge gap still remains to be filled regarding host cell tropism, crucial host immune response mechanisms, and viral markers for virulence. PMID:24003364

Unexpected Abscess Localization of the Anterior Abdominal Wall in an ADPKD Patient Undergoing Hemodialysis.

PubMed

Sabanis, Nikos; Paschou, Eleni; Gavriilaki, Eleni; Mourounoglou, Maria; Vasileiou, Sotirios

2015-01-01

Autosomal Dominant Polycystic Kidney Disease (ADPKD) is one of the most common monogenic disorders and the leading inheritable cause of end-stage renal disease worldwide. Cystic and noncystic extrarenal manifestations are correlated with variable clinical presentations so that an inherited disorder is now considered a systemic disease. Kidney and liver cystic infections are the most common infectious complications in ADPKD patients. Furthermore, it is well known that ADPKD is commonly associated with colonic diverticular disease which recently has been reported to be linked to increased risk of infection on hemodialysis patients. Herein, we present a case of anterior abdominal wall abscess caused by Enterococcus faecalis in a patient with ADPKD undergoing hemodialysis. Although the precise pathway of infection remains uncertain, the previous medical history as well as the clinical course of our patient led us to hypothesize an alternative route of infection from the gastrointestinal tract through an aberrant intestinal barrier into the bloodstream and eventually to an atypical location.

Co-immunization with virus-like particle and DNA vaccines induces protection against respiratory syncytial virus infection and bronchiolitis

PubMed Central

Hwang, Hye Suk; Kwon, Young-Man; Lee, Jong Seok; Yoo, Si-Eun; Lee, Yu-Na; Ko, Eun-Ju; Kim, Min-Chul; Cho, Min-Kyoung; Lee, Young-Tae; Jung, Yu-Jin; Lee, Ji-Yun; Li, Jian Dong; Kang, Sang-Moo

2014-01-01

This study demonstrates that immunization with non-replicating virus-like particle (FFG VLP) containing RSV F and G glycoproteins together with RSV F DNA induced T helper type 1 antibody responses to RSV F similar to live RSV infection. Upon RSV challenge 21 weeks after immunization, FFG VLP vaccination induced protection against RSV infection as shown by clearance of lung viral loads, and the absence of eosinophil infiltrates, and did not cause lung pathology. In contrast, formalin-inactivated RSV (FI-RSV) vaccination showed significant pulmonary eosinophilia, severe mucus production, and extensive histopathology resulting in a hallmark of pulmonary pathology. Substantial lung pathology was also observed in mice with RSV re-infections. High levels of systemic and local inflammatory cytokine-secreting cells were induced in mice with FI-RSV but not with FFG VLP immunization after RSV challenge. Therefore, the results provide evidence that recombinant RSV FFG VLP vaccine can confer long-term protection against RSV without causing lung pathology. PMID:25110201

Sperm Morphological Features Associated with Chronic Chagas Disease in the Semen of Experimentally Infected Dogs

PubMed Central

Rodríguez-Morales, Olivia; Pedro-Martínez, Elvia; Hernández-Pichardo, José Ernesto; Alejandre-Aguilar, Ricardo; Aranda-Fraustro, Alberto; Graullera-Rivera, Verónica; Arce-Fonseca, Minerva

2014-01-01

The presence of trypanosomatids in the reproductive systems of different mammals (causing genital lesions in the acute stage of the disease) may predispose the animals to low semen quality. However, there are no studies examining the alterations in the sperm morphological features in the chronic stage of Trypanosoma cruzi infection. Knowledge of these aspects is important to understand the other ways of transmission of the Chagas disease. Progressive motility, mass motility, concentration, and sperm morphology of 84 ejaculates of dogs that were chronically infected with T. cruzi were evaluated. Most of the findings were consistent with the reference values and with those obtained from healthy control dogs. The scrotal circumference was not correlated with spermatozoa concentration in the infected animals. In conclusion, the T. cruzi Ninoa (MHOM/MX/1994/Ninoa) strain does not cause significant alterations in the semen quality of dogs experiencing chronic Chagas disease (at concentrations of 5 × 104 to 1 × 106 parasites per animal). PMID:25114010

Viral posterior uveitis

PubMed Central

Lee, Joanne H.; Agarwal, Aniruddha; Mahendradas, Padmamalini; Lee, Cecilia S.; Gupta, Vishali; Pavesio, Carlos E.; Agrawal, Rupesh

2017-01-01

The causes of posterior uveitis can be divided into infectious, autoimmune, or masquerade syndromes. Viral infections, a significant cause of sight-threatening ocular diseases in the posterior segment, include human herpesviruses, measles, rubella, and arboviruses such as dengue, West Nile, and chikungunya virus. Viral posterior uveitis may occur as an isolated ocular disease in congenital or acquired infections or as part of a systemic viral illness. Many viruses remain latent in the infected host with a risk of reactivation that depends on various factors, including virulence and host immunity, age, and comorbidities. Although some viral illnesses are self-limiting and have a good visual prognosis, others, such as cytomegalovirus retinitis or acute retinal necrosis, may result in serious complications and profound vision loss. Since some of these infections may respond well to antiviral therapy, it is important to work up all cases of posterior uveitis to rule out an infectious etiology. We review the clinical features, diagnostic tools, treatment regimens, and long-term outcomes for each of these viral posterior uveitides. PMID:28012878

Chromobacterium pathogenicity island 1 type III secretion system is a major virulence determinant for Chromobacterium violaceum-induced cell death in hepatocytes.

PubMed

Miki, Tsuyoshi; Iguchi, Mirei; Akiba, Kinari; Hosono, Masato; Sobue, Tomoyoshi; Danbara, Hirofumi; Okada, Nobuhiko

2010-08-01

Chromobacterium violaceum is a Gram-negative bacterium that causes fatal septicaemia in humans and animals. C. violaceum ATCC 12472 possesses genes associated with two distinct type III secretion systems (T3SSs). One of these systems is encoded by Chromobacterium pathogenicity islands 1 and 1a (Cpi-1/-1a), another is encoded by Chromobacterium pathogenicity island 2 (Cpi-2). Here we show that C. violaceum causes fulminant hepatitis in a mouse infection model, and Cpi-1/-1a-encoded T3SS is required for its virulence. In addition, using C. violaceum strains with defined mutations in the genes that encode the Cpi-1/-1a or Cpi-2 locus in combination with cultured mammalian cell lines, we found that C. violaceum is able to induce cytotoxicity in a Cpi-1/-1a-dependent manner. Characterization of Chromobacterium-induced cytotoxicity revealed that cell lysis by C. violaceum infection involves the formation of pore structures on the host cell membrane, as demonstrated by protection by cytotoxicity in the presence of osmoprotectants. Finally, we demonstrated that CipB, a Cpi-1/-1a effector, is implicated in translocator-mediated pore formation and the ability of CipB to form a pore is essential for Chromobacterium-induced cytotoxicity. These results strongly suggest that Cpi-1/-1a-encoded T3SS is a virulence determinant that causes fatal infection by the induction of cell death in hepatocytes. © 2010 Blackwell Publishing Ltd.

Immunoendocrine abnormalities in the male reproductive system during experimental pulmonary tuberculosis.

PubMed

Ramos Robles, Brenda; Valdez, Ricardo A; Hernández, Uriel Juárez; Marquina Castillo, Brenda; Mata Espinosa, Dulce; Barrios Payan, Jorge; Hernández Pando, Rogelio; Romano, Marta C

2018-03-01

Tuberculosis (TB) is an infectious disease caused by Mycobacterium tuberculosis (Mtb) that mainly affects the lungs. Along the course of pulmonary TB there are remarkable changes in the production of cytokines that cause endocrine changes. So far, it is not known the physiological and histological changes in the male reproductive system during pulmonary TB. To investigate whether pulmonary TB produces histological alterations of the BALB/c mice reproductive organs, as well as abnormalities in spermatogenesis, serum testosterone concentrations and expression of testicular cytokines. BALB/c mice were infected intratracheally with high dose Mtb strain H37Rv. Groups of six non infected and infected animals were euthanized on days 1, 3, 7, 14, 21, 28, 60, 90 and 120 post-infection. Bacillary loads were determined by counting colony forming units (CFUs) in lungs, testes, prostate and seminal vesicles. Histological sections were obtained from the same organs. Spermatozoids number and quality were assessed by spermatobioscopy. Serum testosterone concentrations were determined by radioimmunoanalysis (RIA) in control and infected mice in each time of sacrifice. Mtb only grew in lung tissue. Serum androgens showed a trend to decrease in the infected mice compared to the healthy animals, the difference turn into statistically significance at post infection day 120. The weight of the testis was not modified throughout the study, and no histopathological changes were found. However, we detected a significant decrease in the weight of the seminal vesicles and prostate starting at 28 days post-infection. Atrophy of the seminal vesicles and prostate epithelia were significant, beginning after 60 days of infection. Spermatobioscopy revealed hypospermia in the later stages of the disease. We have observed in the testes a local significant disbalance on the cytokine profile (increase of IL-6 and decrease of IL-10 and TGF-b levels) together with a very significant reduction of the body weight during late pulmonary TB. Pulmonary TB affects the histophysiology of the male reproductive system due to hormonal changes, an imbalance of pro-inflammatory cytokine profile, and a wasting syndrome during late disease. Copyright © 2018. Published by Elsevier Ltd.

Aeromonas caviae alters the cytosolic and mitochondrial creatine kinase activities in experimentally infected silver catfish: Impairment on renal bioenergetics.

PubMed

Baldissera, Matheus D; Souza, Carine F; Júnior, Guerino B; Verdi, Camila Marina; Moreira, Karen L S; da Rocha, Maria Izabel U M; da Veiga, Marcelo L; Santos, Roberto C V; Vizzotto, Bruno S; Baldisserotto, Bernardo

2017-09-01

Cytosolic and mitochondrial creatine kinases (CK), through the creatine kinase-phosphocreatine (CK/PCr) system, provide a temporal and spatial energy buffer to maintain cellular energy homeostasis. However, the effects of bacterial infections on the kidney remain poorly understood and are limited only to histopathological analyses. Thus, the aim of this study was to investigate the involvement of cytosolic and mitochondrial CK activities in renal energetic homeostasis in silver catfish experimentally infected with Aeromonas caviae. Cytosolic CK activity decreased in infected animals, while mitochondrial CK activity increased compared to uninfected animals. Moreover, the activity of the sodium-potassium pump (Na + , K + -ATPase) decreased in infected animals compared to uninfected animals. Based on this evidence, it can be concluded that the inhibition of cytosolic CK activity by A. caviae causes an impairment on renal energy homeostasis through the depletion of adenosine triphosphate (ATP) levels. This contributes to the inhibition of Na + , K + -ATPase activity, although the mitochondrial CK activity acted in an attempt to restore the cytosolic ATP levels through a feedback mechanism. In summary, A. caviae infection causes a severe energetic imbalance in infected silver catfish, which may contribute to disease pathogenesis. Copyright © 2017 Elsevier Ltd. All rights reserved.

Novel Rat Model for Neurocysticercosis Using Taenia solium

PubMed Central

Verastegui, Manuela R.; Mejia, Alan; Clark, Taryn; Gavidia, Cesar M.; Mamani, Javier; Ccopa, Fredy; Angulo, Noelia; Chile, Nancy; Carmen, Rogger; Medina, Roxana; García, Hector H.; Rodriguez, Silvia; Ortega, Ynes; Gilman, Robert H.

2016-01-01

Neurocysticercosis is caused by Taenia solium infecting the central nervous system and is the leading cause of acquired epilepsy and convulsive conditions worldwide. Research into the pathophysiology of the disease and appropriate treatment is hindered by lack of cost-effective and physiologically similar animal models. We generated a novel rat neurocysticercosis model using intracranial infection with activated T. solium oncospheres. Holtzman rats were infected in two separate groups: the first group was inoculated extraparenchymally and the second intraparenchymally, with different doses of activated oncospheres. The groups were evaluated at three different ages. Histologic examination of the tissue surrounding T. solium cysticerci was performed. Results indicate that generally infected rats developed cysticerci in the brain tissue after 4 months, and the cysticerci were observed in the parenchymal, ventricle, or submeningeal brain tissue. The route of infection did not have a statistically significant effect on the proportion of rats that developed cysticerci, and there was no dependence on infection dose. However, rat age was crucial to the success of the infection. Epilepsy was observed in 9% of rats with neurocysticercosis. In histologic examination, a layer of collagen tissue, inflammatory infiltrate cells, perivascular infiltrate, angiogenesis, spongy change, and mass effect were observed in the tissue surrounding the cysts. This study presents a suitable animal model for the study of human neurocysticercosis. PMID:26216286

Human Adenovirus Type 37 Uses αVβ1 and α3β1 Integrins for Infection of Human Corneal Cells

PubMed Central

Storm, Rickard J.; Persson, B. David; Skalman, Lars Nygård; Frängsmyr, Lars; Lindström, Mona; Rankin, Greg; Lundmark, Richard; Domellöf, Fatima Pedrosa

2016-01-01

ABSTRACT Epidemic keratoconjunctivitis (EKC) is a severe, contagious ocular disease that affects 20 to 40 million individuals worldwide every year. EKC is mainly caused by six types of human adenovirus (HAdV): HAdV-8, -19, -37, -53, -54, and -56. Of these, HAdV-8, -19, and -37 use sialic acid-containing glycans as cellular receptors. αVβ3, αVβ5, and a few additional integrins facilitate entry and endosomal release of other HAdVs. With the exception of a few biochemical analyses indicating that HAdV-37 can interact physically with αVβ5, little is known about the integrins used by EKC-causing HAdVs. Here, we investigated the overall integrin expression on human corneal cells and found expression of α2, α3, α6, αV, β1, and β4 subunits in human corneal in situ epithelium and/or in a human corneal epithelial (HCE) cell line but no or less accessible expression of α4, α5, β3, or β5. We also identified the integrins used by HAdV-37 through a series of binding and infection competition experiments and different biochemical approaches. Together, our data suggest that HAdV-37 uses αVβ1 and α3β1 integrins for infection of human corneal epithelial cells. Furthermore, to confirm the relevance of these integrins in the HAdV-37 life cycle, we developed a corneal multilayer tissue system and found that HAdV-37 infection correlated well with the patterns of αV, α3, and β1 integrin expression. These results provide further insight into the tropism and pathogenesis of EKC-causing HAdVs and may be of importance for future development of new antiviral drugs. IMPORTANCE Keratitis is a hallmark of EKC, which is caused by six HAdV types (HAdV-8, -19, -37, -53, -54, and -56). HAdV-37 and some other HAdV types interact with integrin αVβ5 in order to enter nonocular human cells. In this study, we found that αVβ5 is not expressed on human corneal epithelial cells, thus proposing other host factors mediate corneal infection. Here, we first characterized integrin expression patterns on corneal tissue and corneal cells. Among the integrins identified, competition binding and infection experiments and biochemical assays pointed out αVβ1 and α3β1 to be of importance for HAdV-37 infection of corneal tissue. In the absence of a good animal model for EKC-causing HAdVs, we also developed an in vitro system with multilayer HCE cells and confirmed the relevance of the suggested integrins during HAdV-37 infection. PMID:27974569

Trichuris muris: a model of gastrointestinal parasite infection.

PubMed

Klementowicz, Joanna E; Travis, Mark A; Grencis, Richard K

2012-11-01

Infection with soil-transmitted gastrointestinal parasites, such as Trichuris trichiura, affects more than a billion people worldwide, causing significant morbidity and health problems especially in poverty-stricken developing countries. Despite extensive research, the role of the immune system in triggering parasite expulsion is incompletely understood which hinders the development of anti-parasite therapies. Trichuris muris infection in mice serves as a useful model of T. trichiura infection in humans and has proven to be an invaluable tool in increasing our understanding of the role of the immune system in promoting either susceptibility or resistance to infection. The old paradigm of a susceptibility-associated Th1 versus a resistance-associated Th2-type response has been supplemented in recent years with cell populations such as novel innate lymphoid cells, basophils, dendritic cells and regulatory T cells proposed to play an active role in responses to T. muris infection. Moreover, new immune-controlled mechanisms of expulsion, such as increased epithelial cell turnover and mucin secretion, have been described in recent years increasing the number of possible targets for anti-parasite therapies. In this review, we give a comprehensive overview of experimental work conducted on the T. muris infection model, focusing on important findings and the most recent reports on the role of the immune system in parasite expulsion.

Retrospective, Demographic, and Clinical Investigation of the Causes of Postoperative Infection in Patients With Lumbar Spinal Stenosis Who Underwent Posterior Stabilization.

PubMed

Yaldiz, Can; Yaldiz, Mahizer; Ceylan, Nehir; Kacira, Ozlem Kitiki; Ceylan, Davut; Kacira, Tibet; Kizilcay, Gokhan; Tanriverdi, Taner

2015-07-01

Owing to the increasing population of elderly patients, a large number of patients with degenerative spondylosis are currently being surgically treated. Although basic measures for decreasing postoperative surgical infections (PSIs) are considered, it still remains among the leading causes of morbidity and mortality. The aim of this retrospective analysis is to present possible causes leading to PSI in patients who underwent surgery for lumbar degenerative spondylosis and highlight how it can be avoided to decrease morbidity and mortality. The study included 540 patients who underwent posterior stabilization due to degenerative lumbar stenosis between January 2013 and January 2014. The data before and after surgery was retrieved from the hospital charts. Patients with degenerative lumbar stenosis who were operated upon in this study had >2 levels of laminectomy and facetectomy. For this reason, posterior stabilization was performed for all the patients included in this study. Determining the causes of postoperative infection (PI) following spinal surgeries performed with instrumentation is a struggle. Seventeen different parameters that may be related to PI were evaluated in this study. The presence of systemic diseases, unknown glove perforations, and perioperative blood transfusions were among the parameters that increased the prevalence of PI. Alternatively, prolene sutures, double-layered gloves, and the use of rifampicin Sv (RIS) decreased the incidence of PI. Although the presence of systemic diseases, unnoticed glove perforations, and perioperative blood transfusions increased PIs, prolene suture material, double-layered gloves, and the use of RIS decreased PIs.

Type I Interferons and NK Cells Restrict Gammaherpesvirus Lymph Node Infection.

PubMed

Lawler, Clara; Tan, Cindy S E; Simas, J Pedro; Stevenson, Philip G

2016-10-15

Gammaherpesviruses establish persistent, systemic infections and cause cancers. Murid herpesvirus 4 (MuHV-4) provides a unique window into the early events of host colonization. It spreads via lymph nodes. While dendritic cells (DC) pass MuHV-4 to lymph node B cells, subcapsular sinus macrophages (SSM), which capture virions from the afferent lymph, restrict its spread. Understanding how this restriction works offers potential clues to a more comprehensive defense. Type I interferon (IFN-I) blocked SSM lytic infection and reduced lytic cycle-independent viral reporter gene expression. Plasmacytoid DC were not required, but neither were SSM the only source of IFN-I, as IFN-I blockade increased infection in both intact and SSM-depleted mice. NK cells restricted lytic SSM infection independently of IFN-I, and SSM-derived virions spread to the spleen only when both IFN-I responses and NK cells were lacking. Thus, multiple innate defenses allowed SSM to adsorb virions from the afferent lymph with relative impunity. Enhancing IFN-I and NK cell recruitment could potentially also restrict DC infection and thus improve infection control. Human gammaherpesviruses cause cancers by infecting B cells. However, vaccines designed to block virus binding to B cells have not stopped infection. Using a related gammaherpesvirus of mice, we have shown that B cells are infected not via cell-free virus but via infected myeloid cells. This suggests a different strategy to stop B cell infection: stop virus production by myeloid cells. Not all myeloid infection is productive. We show that subcapsular sinus macrophages, which do not pass infection to B cells, restrict gammaherpesvirus production by recruiting type I interferons and natural killer cells. Therefore, a vaccine that speeds the recruitment of these defenses might stop B cell infection. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

Type I Interferons and NK Cells Restrict Gammaherpesvirus Lymph Node Infection

PubMed Central

Lawler, Clara; Tan, Cindy S. E.; Simas, J. Pedro

2016-01-01

ABSTRACT Gammaherpesviruses establish persistent, systemic infections and cause cancers. Murid herpesvirus 4 (MuHV-4) provides a unique window into the early events of host colonization. It spreads via lymph nodes. While dendritic cells (DC) pass MuHV-4 to lymph node B cells, subcapsular sinus macrophages (SSM), which capture virions from the afferent lymph, restrict its spread. Understanding how this restriction works offers potential clues to a more comprehensive defense. Type I interferon (IFN-I) blocked SSM lytic infection and reduced lytic cycle-independent viral reporter gene expression. Plasmacytoid DC were not required, but neither were SSM the only source of IFN-I, as IFN-I blockade increased infection in both intact and SSM-depleted mice. NK cells restricted lytic SSM infection independently of IFN-I, and SSM-derived virions spread to the spleen only when both IFN-I responses and NK cells were lacking. Thus, multiple innate defenses allowed SSM to adsorb virions from the afferent lymph with relative impunity. Enhancing IFN-I and NK cell recruitment could potentially also restrict DC infection and thus improve infection control. IMPORTANCE Human gammaherpesviruses cause cancers by infecting B cells. However, vaccines designed to block virus binding to B cells have not stopped infection. Using a related gammaherpesvirus of mice, we have shown that B cells are infected not via cell-free virus but via infected myeloid cells. This suggests a different strategy to stop B cell infection: stop virus production by myeloid cells. Not all myeloid infection is productive. We show that subcapsular sinus macrophages, which do not pass infection to B cells, restrict gammaherpesvirus production by recruiting type I interferons and natural killer cells. Therefore, a vaccine that speeds the recruitment of these defenses might stop B cell infection. PMID:27466430

The novel species Streptococcus tigurinus and its association with oral infection.

PubMed

Zbinden, Andrea; Bostanci, Nagihan; Belibasakis, Georgios N

2015-01-01

Streptococcus tigurinus is a novel species of viridans streptococci, shown to cause severe invasive infections such as infective endocarditis, spondylodiscitis and meningitis. S. tigurinus belongs to the Streptococcus mitis group and is most closely related to Streptococcus mitis, Streptococcus oralis, Streptococcus pneumoniae, Streptococcus pseudopneumoniae and Streptococcus infantis. The presence of S. tigurinus in the human oral cavity has been documented, including in patients with periodontal disease. This review addresses the available scientific knowledge on S. tigurinus and its association with closely related streptococci, and discusses its putative involvement in common oral infections. While there is as yet no strong evidence on the involvement of S. tigurinus with oral infections, its presence in the oral cavity and its association with endocarditis warrants special attention for a link between oral and systemic infection.

Neurognathostomiasis, a neglected parasitosis of the central nervous system.

PubMed

Katchanov, Juri; Sawanyawisuth, Kittisak; Chotmongkoi, Verajit; Nawa, Yukifumi

2011-07-01

Gnathostomiasis is a foodborne zoonotic helminthic infection caused by the third-stage larvae of Gnathostoma spp. nematodes. The most severe manifestation involves infection of the central nervous system, neurognathostomiasis. Although gnathostomiasis is endemic to Asia and Latin America, almost all neurognathostomiasis cases are reported from Thailand. Despite high rates of illness and death, neurognathostomiasis has received less attention than the more common cutaneous form of gnathostomiasis, possibly because of the apparent geographic confinement of the neurologic infection to 1 country. Recently, however, the disease has been reported in returned travelers in Europe. We reviewed the English-language literature on neurognathostomiasis and analyzed epidemiology and geographic distribution, mode of central nervous system invasion, pathophysiology, clinical features, neuroimaging data, and treatment options. On the basis of epidemiologic data, clinical signs, neuroimaging, and laboratory findings, we propose diagnostic criteria for neurognathostomiasis.

From inflammation to sickness and depression: when the immune system subjugates the brain.

PubMed

Dantzer, Robert; O'Connor, Jason C; Freund, Gregory G; Johnson, Rodney W; Kelley, Keith W

2008-01-01

In response to a peripheral infection, innate immune cells produce pro-inflammatory cytokines that act on the brain to cause sickness behaviour. When activation of the peripheral immune system continues unabated, such as during systemic infections, cancer or autoimmune diseases, the ensuing immune signalling to the brain can lead to an exacerbation of sickness and the development of symptoms of depression in vulnerable individuals. These phenomena might account for the increased prevalence of clinical depression in physically ill people. Inflammation is therefore an important biological event that might increase the risk of major depressive episodes, much like the more traditional psychosocial factors.

Central venous catheter-related infections in patients receiving short-term hemodialysis therapy: incidence, associated factors, and microbiological aspects.

PubMed

Menegueti, Mayra Gonçalves; Betoni, Natália Cristina; Bellissimo-Rodrigues, Fernando; Romão, Elen Almeida

2017-01-01

Bloodstream infections are the second most common cause of death among patients on hemodialysis. This study aimed to evaluate the incidence of and risk factors associated with central venous catheter-related infections in patients undergoing hemodialysis, and to identify and characterize the type and antimicrobial susceptibility profiles of the primary microorganisms isolated during one year of follow-up. A prospective cohort study was conducted in 2014 in a hemodialysis referral center. We included 200 outpatients with acute kidney injury who had no permanent venous access. A nurse assessed the patients for signs of infection three times per week during dressing changes. The clinicopathologic characteristics of patients with and without local or systemic infection were compared. Fifty-five episodes of catheter-related infections occurred in 43 (22%) patients; 38 (69%) were bloodstream infections and 17 (31%) were local infections. Thirty-two (75%) patients with infection had femoral vein catheter placement. In total, 6,240 hemodialysis sessions were performed; the rates of primary bloodstream and local infection were 6.1 and 2.7 episodes per 1,000 patients on daily dialysis, respectively. In the univariate analysis, diabetes was significantly associated with the development of infection, while level of education, ethnicity, age, and sex were not. Gram-negative bacteria were primarily isolated from blood culture specimens (55% of samples). Of the Gram-negative isolates, 56% were resistant to the carbapenems. We identified a high incidence of catheter-related infections caused by resistant microorganisms in patients undergoing hemodialysis via central venous catheters.

Odontogenic infections. Complications. Systemic manifestations.

PubMed

Jiménez, Yolanda; Bagán, José Vicente; Murillo, Judith; Poveda, Rafael

2004-01-01

The term, odontogenic infection refers to an infection that originates in the tooth proper or in the tissues that closely surround it; said infection then progresses along the periodontia down to the apex, involving periapical bone and from this area, it then spreads through the bone and periosteum towards near-by or more distant structures. The relevance of this type of infection lies in that it can cause infections that compromise more distant structures (via direct spread and distant spread), for example, intracraneal, retropharyngeal and pulmonary pleural infections. Dissemination by means of the bloodstream can lead to rheumatic problems and deposits on the valves of the heart (endocarditis), etc. The conditions or factors that influence the spread of infection are dependent on the balance between patient-related conditions and microorganism-related conditions. The virulence of the affecting germs is dependent upon their quality and quantity and is one of the microbiological conditions that influences the infection. It is this virulence that promotes infectious invasion and the deleterious effects the microbe will have on the host. Patient-related conditions include certain systemic factors that determine host resistance, which may be impaired in situations such as immunodeficiency syndrome or in brittle diabetes, as well as local factors that will also exert their impact on the spread of the infection.

[Socio-economic aspects of epidemiology of helicobateriosis].

PubMed

Fedichkina, T P; Solenova, L G; Zykova, I E; German, S V; Modestova, A V; Kislitsyn, V A; Rakhmanin, Yu A; Bobrovnitsky, I P

There are considered special social and economic aspects of the epidemiology of Helicobacter pylori. These aspects acquired the particular importance for the last time due to the fact that the provision of the people with pure water has been becoming the focus of the attention of geopolitical and socio-economic interests in a number of countries. The availability ofpure drinking water serves a marker of the socio-economic state of the territory and the population living there. In Russia where different climatic conditions are deposited by considerable regional differences in the conditions of communal services caused both by various level of the socio-economic development of the territory, the supplementation with pure drinking water serves as the social determinant of the ecological conditions of the population’s life. This particularly has impact on the unfeasible technical state of the water distribution systems, microorganism ecology of which can substantially affect public health. The performed by authors a specialized screening ofpresented at the official web site of the joint-stock company «Mosvodokanal» current data concerning the quality of drinking water consumed by 2500 Moscovites, tested for the Helicobacter pylori infection revealed no deviations from the sanitary standards in the water received by the consumers. Along with that, the comparison of the map documents of the distribution of the Helicobacter pylori infection in Moscow with the distribution of citizens’ complaints of the decline of the quality of tap water has revealed a territorial fastening of the high values of the population infection rate of n^ylori and the urban sites with the greatest number of complaints. In the microbial ecology of water-distribution systems there are tightly aligned problems of their epidemiological safety, technical state and economic damage caused by corrosion as a result of microbiotic activity. In contrast to acute bacterial and viral infections which are deemed of the greatest importance when assessing the sanitary condition of water sources and water-distribution systems, the consequences of infection with H. pylori may not be manifestedfor a long time but some years later they may be manifested as serious chronic diseases (from gastritis to adenocarcinoma of the stomach and a wide range of extraintestinal pathologies), which causes great social and economic losses. Thus, the socio-economic aspect of the epidemiology of helicobacteriosis includes at least two components: the technic - the maintenance of the feasible technic and sanitary state of the water distribution systems and the medico-social - expenditures for screening and treatment of infected patients. In total they are an inseparable part of the prevention of socially-important diseases in the public health system.

Incubation Period and Early Natural History Events of the Acute Form of Paracoccidioidomycosis: Lessons from Patients with a Single Paracoccidioides spp. Exposure.

PubMed

Buccheri, Renata; Khoury, Zarifa; Barata, Luis Carlos Barradas; Benard, Gil

2016-06-01

Several aspects of the natural history of paracoccidioidomycosis are still poorly understood. Different from the most prevalent, chronic form of the disease, the acute form represents a continuum from the initial respiratory infection to the full-blown disease, thus providing an opportunity to elucidate the pathogenesis of the early phase of this mycosis. We describe, for the first time, two patients with a single time point exposure to Paracoccidioides spp., for whom we were able to determine the time lapsed between exposure to the fungus Paracoccidioides spp. and the onset of signs and symptoms. In case 1, the pulmonary infection was unapparent, and the first manifestations of the acute/subacute form of the disease presented 4 months after Paracoccidioides spp. In case 2, self-limited, non-specific respiratory and systemic symptoms presented 45 days after infection. Thus, our patients confirm that, within a few weeks of infection, Paracoccidioides spp. affects the pulmonary lymphatic system and initially causes no or mild-to-moderate self-limited symptoms, eventually causing abnormalities on a chest X-ray, all of which spontaneously subside. These cases provide some insight into the natural history of this mycosis, the extent of the host exposure to the fungus, and the determination of its incubation period.

UroPathogenic Escherichia coli (UPEC) Infections: Virulence Factors, Bladder Responses, Antibiotic, and Non-antibiotic Antimicrobial Strategies

PubMed Central

Terlizzi, Maria E.; Gribaudo, Giorgio; Maffei, Massimo E.

2017-01-01

Urinary tract infections (UTIs) are one of the most common pathological conditions in both community and hospital settings. It has been estimated that about 150 million people worldwide develop UTI each year, with high social costs in terms of hospitalizations and medical expenses. Among the common uropathogens associated to UTIs development, UroPathogenic Escherichia coli (UPEC) is the primary cause. UPEC strains possess a plethora of both structural (as fimbriae, pili, curli, flagella) and secreted (toxins, iron-acquisition systems) virulence factors that contribute to their capacity to cause disease, although the ability to adhere to host epithelial cells in the urinary tract represents the most important determinant of pathogenicity. On the opposite side, the bladder epithelium shows a multifaceted array of host defenses including the urine flow and the secretion of antimicrobial substances, which represent useful tools to counteract bacterial infections. The fascinating and intricate dynamics between these players determine a complex interaction system that needs to be revealed. This review will focus on the most relevant components of UPEC arsenal of pathogenicity together with the major host responses to infection, the current approved treatment and the emergence of resistant UPEC strains, the vaccine strategies, the natural antimicrobial compounds along with innovative anti-adhesive and prophylactic approaches to prevent UTIs. PMID:28861072

Immunology of Yersinia pestis Infection.

PubMed

Bi, Yujing

2016-01-01

As a pathogen of plague, Yersinia pestis caused three massive pandemics in history that killed hundreds of millions of people. Yersinia pestis is highly invasive, causing severe septicemia which, if untreated, is usually fatal to its host. To survive in the host and maintain a persistent infection, Yersinia pestis uses several stratagems to evade the innate and the adaptive immune responses. For example, infections with this organism are biphasic, involving an initial "noninflammatory" phase where bacterial replication occurs initially with little inflammation and following by extensive phagocyte influx, inflammatory cytokine production, and considerable tissue destruction, which is called "proinflammatory" phase. In contrast, the host also utilizes its immune system to eliminate the invading bacteria. Neutrophil and macrophage are the first defense against Yersinia pestis invading through phagocytosis and killing. Other innate immune cells also play different roles, such as dendritic cells which help to generate more T helper cells. After several days post infection, the adaptive immune response begins to provide organism-specific protection and has a long-lasting immunological memory. Thus, with the cooperation and collaboration of innate and acquired immunity, the bacterium may be eliminated from the host. The research of Yersinia pestis and host immune systems provides an important topic to understand pathogen-host interaction and consequently develop effective countermeasures.

ANA testing in the presence of acute and chronic infections.

PubMed

Litwin, Christine M; Binder, Steven R

2016-01-01

Autoantibody testing is performed to help diagnose patients who have clinical symptoms suggestive of possible autoimmune diseases. Antinuclear antibodies (ANA) are present in many systemic autoimmune conditions such as systemic lupus erythematosus (SLE). However, a positive ANA test may also be seen with non-autoimmune inflammatory diseases, including both acute and chronic infections. When the ANA test is used as an initial screen in patients with non-specific clinical symptoms, such as fever, joint pain, myalgias, fatigue, rash, or anemia, the likelihood of a positive result due to infection will increase, especially in children. This article identifies acute and chronic infectious diseases that are likely to produce a positive ANA result and summarizes recent literature addressing both the causes and consequences of these findings.

AFRRI reports. First Quarter, January-March 1991. Scientific report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1991-04-01

Ionizing radiation reduces the host's defenses to infection (1) and enhances its susceptibility to systemic infection due to endogenous and exogenous organisms. Klebsiella pneumoniae is one of the most frequent causes of gram-negative bacteremia, and is especially prevalent in immunocompromised patients. Therapy for severe systemic infection due to gram-negative bacteria generally involves the use of aminoglycosides in combination with beta lactam antibiotics. However, several recently developed quinolone compounds have exhibited high in vitro bactericidal activity against most gram negative bacteria. including K. pneumoniae. In this study, the authors evaluated the efficacy of oral therapy with several quinolones in a modelmore » of experimental septicemia due to orally ingested K pneumoniae in irradiated mice.« less

Acute disseminated encephalomyelitis and thrombocytopenia following Epstein-Barr virus infection.

PubMed

Saeed, Muhammad; Dabbagh, Omar; Al-Muhaizae, Muhammad; Dhalaan, Hesham; Chedrawi, Aziza

2014-11-01

Epstein-Barr Virus (EBV) causes a broad spectrum of disease in humans with several clinical syndromes and is ubiquitous, infecting more than 95% of the world's population. Central Nervous System (CNS) disease alone associated with Epstein-Barr virus rarely occurs in previously healthy individuals. Systemic viral illness in children and complications are rare, but may occur. In few cases, it is associated with a variety of CNS and hematological complications like acute disseminated encephalomyelitis, transverse myelitis, neuropsychiatric syndrome, GBS, autoimmune thrombocytopenia and hemolytic anemia and they usually respond to immunotherapy. We report previously healthy boy, who presented with left sided weakness, headache and thrombocytopenia following EBV infection. The thrombocytopenia was resistant to intravenous immunoglobulin and methylprednisolone but responded well to Rituximab.

Dentistry and internal medicine: from the focal infection theory to the periodontal medicine concept.

PubMed

Pizzo, Giuseppe; Guiglia, Rosario; Lo Russo, Lucio; Campisi, Giuseppina

2010-12-01

During past decades the relationship between dentistry and internal medicine and especially the concept of the so-called focal infection theory have long been a matter of debate. The pathogenesis of focal diseases has been classically attributed to dental pulp pathologies and periapical infections. Nonetheless, in recent years, their role is being dismissed while increasing interest is being devoted to the possible associations between periodontal infection and systemic diseases. In fact, periodontal pathogens and their products, as well as inflammatory mediators produced in periodontal tissues, might enter the bloodstream, causing systemic effects and/or contributing to systemic diseases. On the basis of this mechanism, chronic periodontitis has been suggested as a risk factor for cardiovascular diseases associated with atherosclerosis, bacterial endocarditis, diabetes mellitus, respiratory disease, preterm delivery, rheumatoid arthritis, and, recently, osteoporosis, pancreatic cancer, metabolic syndrome, renal diseases and neurodegenerative diseases such as Alzheimer's disease. Various hypotheses, including common susceptibility, systemic inflammation, direct bacterial infection and cross-reactivity, or molecular mimicry, between bacterial antigens and self-antigens, have been postulated to explain these relationships. In this scenario, the association of periodontal disease with systemic diseases has set the stage for introducing the concept of periodontal medicine. This narrative review summarizes the evolution of focal infection theory up to the current pathophysiology of periodontal disease, and presents an update on the relationships between chronic periodontitis and systemic diseases. Copyright © 2010 European Federation of Internal Medicine. Published by Elsevier B.V. All rights reserved.

“Viral déjà vu” elicits organ-specific immune disease independent of reactivity to self

PubMed Central

Merkler, Doron; Horvath, Edit; Bruck, Wolfgang; Zinkernagel, Rolf M.; del la Torre, Juan Carlos; Pinschewer, Daniel D.

2006-01-01

Autoimmune diseases are often precipitated by viral infections. Yet our current understanding fails to explain how viruses trigger organ-specific autoimmunity despite thymic tolerance extending to many nonlymphohematopoietic self antigens. Additionally, a key epidemiological finding needs to be explained: In genetically susceptible individuals, early childhood infections seem to predispose them to multiple sclerosis (MS) or type 1 diabetes years or even decades before clinical onset. In the present work, we show that the innate immune system of neonatal mice was sufficient to eliminate an attenuated lymphocytic choriomeningitis virus (LCMV) from most tissues except for the CNS, where the virus persisted in neurons (predisposing virus). Virus-specific cytotoxic T cells (CTLs) were neither deleted nor sufficiently primed to cause disease, but they were efficiently triggered in adulthood upon WT LCMV infection (precipitating virus). This defined sequence of viral infections caused severe CNS inflammation that was histomorphologically reminiscent of rasmussen encephalitis, a fatal human autoimmune disease. Yet disease in mice was mediated by antiviral CTLs targeting an epitope shared by the precipitating virus and the predisposing virus persisting in neurons (déjà vu). Thus the concept of “viral déjà vu” demonstrates how 2 related but independently encountered viral infections can cause organ-specific immune disease without molecular mimicry of self and without breaking self tolerance. PMID:16604192

Streptococcal acute pharyngitis.

PubMed

Anjos, Lais Martins Moreira; Marcondes, Mariana Barros; Lima, Mariana Ferreira; Mondelli, Alessandro Lia; Okoshi, Marina Politi

2014-07-01

Acute pharyngitis/tonsillitis, which is characterized by inflammation of the posterior pharynx and tonsils, is a common disease. Several viruses and bacteria can cause acute pharyngitis; however, Streptococcus pyogenes (also known as Lancefield group A β-hemolytic streptococci) is the only agent that requires an etiologic diagnosis and specific treatment. S. pyogenes is of major clinical importance because it can trigger post-infection systemic complications, acute rheumatic fever, and post-streptococcal glomerulonephritis. Symptom onset in streptococcal infection is usually abrupt and includes intense sore throat, fever, chills, malaise, headache, tender enlarged anterior cervical lymph nodes, and pharyngeal or tonsillar exudate. Cough, coryza, conjunctivitis, and diarrhea are uncommon, and their presence suggests a viral cause. A diagnosis of pharyngitis is supported by the patient's history and by the physical examination. Throat culture is the gold standard for diagnosing streptococcus pharyngitis. However, it has been underused in public health services because of its low availability and because of the 1- to 2-day delay in obtaining results. Rapid antigen detection tests have been used to detect S. pyogenes directly from throat swabs within minutes. Clinical scoring systems have been developed to predict the risk of S. pyogenes infection. The most commonly used scoring system is the modified Centor score. Acute S. pyogenes pharyngitis is often a self-limiting disease. Penicillins are the first-choice treatment. For patients with penicillin allergy, cephalosporins can be an acceptable alternative, although primary hypersensitivity to cephalosporins can occur. Another drug option is the macrolides. Future perspectives to prevent streptococcal pharyngitis and post-infection systemic complications include the development of an anti-Streptococcus pyogenes vaccine.

Porcine epidemic diarrhea virus infection: Etiology, epidemiology, pathogenesis and immunoprophylaxis.

PubMed

Jung, Kwonil; Saif, Linda J

2015-05-01

Porcine epidemic diarrhea virus (PEDV), a member of the genera Alphacoronavirus in the family Coronaviridae, causes acute diarrhea/vomiting, dehydration and high mortality in seronegative neonatal piglets. For the last three decades, PEDV infection has resulted in significant economic losses in the European and Asian pig industries, but in 2013-2014 the disease was also reported in the US, Canada and Mexico. The PED epidemic in the US, from April 2013 to the present, has led to the loss of more than 10% of the US pig population. The disappearance and re-emergence of epidemic PED indicates that the virus is able to escape from current vaccination protocols, biosecurity and control systems. Endemic PED is a significant problem, which is exacerbated by the emergence (or potential importation) of multiple PEDV variants. Epidemic PEDV strains spread rapidly and cause a high number of pig deaths. These strains are highly enteropathogenic and acutely infect villous epithelial cells of the entire small and large intestines although the jejunum and ileum are the primary sites. PEDV infections cause acute, severe atrophic enteritis accompanied by viremia that leads to profound diarrhea and vomiting, followed by extensive dehydration, which is the major cause of death in nursing piglets. A comprehensive understanding of the pathogenic characteristics of epidemic or endemic PEDV strains is needed to prevent and control the disease in affected regions and to develop an effective vaccine. This review focuses on the etiology, epidemiology, disease mechanisms and pathogenesis as well as immunoprophylaxis against PEDV infection. Copyright © 2015 Elsevier Ltd. All rights reserved.

Parvovirus B19 infection presenting concurrently as papular-purpuric gloves-and-socks syndrome and bathing-trunk eruption.

PubMed

Vázquez-Osorio, I; Mallo-García, S; Rodríguez-Díaz, E; Gonzalvo-Rodríguez, P; Requena, L

2017-01-01

Parvovirus B19 infection can cause a wide range of cutaneous manifestations, including papular-purpuric gloves-and-socks syndrome (PPGSS) and petechial bathing trunk eruption. We report a case of an immunocompetent woman with a primary parvovirus B19 infection presenting as concurrent PPGSS and petechial bathing trunk eruption. Parvovirus B19 seroconversion was confirmed several days after the onset of the clinical manifestations. The coexistence of these two cutaneous manifestations of primary parvovirus B19 infection has rarely been reported in the literature. It is important to recognize parvovirus B19 infection early, based on the cutaneous manifestations, to avoid potentially serious systemic complications in susceptible individuals. © 2016 British Association of Dermatologists.

Streptococcus pneumoniae and Pseudomonas aeruginosa pneumonia induce distinct host responses

PubMed Central

McConnell, Kevin W.; McDunn, Jonathan E.; Clark, Andrew T.; Dunne, W. Michael; Dixon, David J.; Turnbull, Isaiah R.; DiPasco, Peter J.; Osberghaus, William F.; Sherman, Benjamin; Martin, James R.; Walter, Michael J.; Cobb, J. Perren; Buchman, Timothy G.; Hotchkiss, Richard S.; Coopersmith, Craig M.

2009-01-01

Objective Pathogens that cause pneumonia may be treated in a targeted fashion by antibiotics, but if this therapy fails, treatment involves only non-specific supportive measures, independent of the inciting infection. The purpose of this study was to determine whether host response is similar following disparate infections with similar mortalities. Design Prospective, randomized controlled study. Setting Animal laboratory in a university medical center. Interventions Pneumonia was induced in FVB/N mice by either Streptococcus pneumoniae or two different concentrations of Pseudomonas aeruginosa. Plasma and bronchoalveolar lavage fluid from septic animals was assayed by a microarray immunoassay measuring 18 inflammatory mediators at multiple timepoints. Measurements and Main Results The host response was dependent upon the causative organism as well as kinetics of mortality, but the pro- and anti- inflammatory response was independent of inoculum concentration or degree of bacteremia. Pneumonia caused by different concentrations of the same bacteria, Pseudomonas aeruginosa, also yielded distinct inflammatory responses; however, inflammatory mediator expression did not directly track the severity of infection. For all infections, the host response was compartmentalized, with markedly different concentrations of inflammatory mediators in the systemic circulation and the lungs. Hierarchical clustering analysis resulted in the identification of 5 distinct clusters of the host response to bacterial infection. Principal components analysis correlated pulmonary MIP-2 and IL-10 with progression of infection while elevated plasma TNFsr2 and MCP-1 were indicative of fulminant disease with >90% mortality within 48 hours. Conclusions Septic mice have distinct local and systemic responses to Streptococcus pneumoniae and Pseudomonas aeruginosa pneumonia. Targeting specific host inflammatory responses induced by distinct bacterial infections could represent a potential therapeutic approach in the treatment of sepsis. PMID:19770740

Streptococcus pneumoniae and Pseudomonas aeruginosa pneumonia induce distinct host responses.

PubMed

McConnell, Kevin W; McDunn, Jonathan E; Clark, Andrew T; Dunne, W Michael; Dixon, David J; Turnbull, Isaiah R; Dipasco, Peter J; Osberghaus, William F; Sherman, Benjamin; Martin, James R; Walter, Michael J; Cobb, J Perren; Buchman, Timothy G; Hotchkiss, Richard S; Coopersmith, Craig M

2010-01-01

Pathogens that cause pneumonia may be treated in a targeted fashion by antibiotics, but if this therapy fails, then treatment involves only nonspecific supportive measures, independent of the inciting infection. The purpose of this study was to determine whether host response is similar after disparate infections with similar mortalities. Prospective, randomized controlled study. Animal laboratory in a university medical center. Pneumonia was induced in FVB/N mice by either Streptococcus pneumoniae or two different concentrations of Pseudomonas aeruginosa. Plasma and bronchoalveolar lavage fluid from septic animals was assayed by a microarray immunoassay measuring 18 inflammatory mediators at multiple time points. The host response was dependent on the causative organism as well as kinetics of mortality, but the pro-inflammatory and anti-inflammatory responses were independent of inoculum concentration or degree of bacteremia. Pneumonia caused by different concentrations of the same bacteria, Pseudomonas aeruginosa, also yielded distinct inflammatory responses; however, inflammatory mediator expression did not directly track the severity of infection. For all infections, the host response was compartmentalized, with markedly different concentrations of inflammatory mediators in the systemic circulation and the lungs. Hierarchical clustering analysis resulted in the identification of five distinct clusters of the host response to bacterial infection. Principal components analysis correlated pulmonary macrophage inflammatory peptide-2 and interleukin-10 with progression of infection, whereas elevated plasma tumor necrosis factor sr2 and macrophage chemotactic peptide-1 were indicative of fulminant disease with >90% mortality within 48 hrs. Septic mice have distinct local and systemic responses to Streptococcus pneumoniae and Pseudomonas aeruginosa pneumonia. Targeting specific host inflammatory responses induced by distinct bacterial infections could represent a potential therapeutic approach in the treatment of sepsis.

Hippocampal TNFα Signaling Contributes to Seizure Generation in an Infection-Induced Mouse Model of Limbic Epilepsy.

PubMed

Patel, Dipan C; Wallis, Glenna; Dahle, E Jill; McElroy, Pallavi B; Thomson, Kyle E; Tesi, Raymond J; Szymkowski, David E; West, Peter J; Smeal, Roy M; Patel, Manisha; Fujinami, Robert S; White, H Steve; Wilcox, Karen S

2017-01-01

Central nervous system infection can induce epilepsy that is often refractory to established antiseizure drugs. Previous studies in the Theiler's murine encephalomyelitis virus (TMEV)-induced mouse model of limbic epilepsy have demonstrated the importance of inflammation, especially that mediated by tumor necrosis factor-α (TNFα), in the development of acute seizures. TNFα modulates glutamate receptor trafficking via TNF receptor 1 (TNFR1) to cause increased excitatory synaptic transmission. Therefore, we hypothesized that an increase in TNFα signaling after TMEV infection might contribute to acute seizures. We found a significant increase in both mRNA and protein levels of TNFα and the protein expression ratio of TNF receptors (TNFR1:TNFR2) in the hippocampus, a brain region most likely involved in seizure initiation, after TMEV infection, which suggests that TNFα signaling, predominantly through TNFR1, may contribute to limbic hyperexcitability. An increase in hippocampal cell-surface glutamate receptor expression was also observed during acute seizures. Although pharmacological inhibition of TNFR1-mediated signaling had no effect on acute seizures, several lines of genetically modified animals deficient in either TNFα or TNFRs had robust changes in seizure incidence and severity after TMEV infection. TNFR2 -/- mice were highly susceptible to developing acute seizures, suggesting that TNFR2-mediated signaling may provide beneficial effects during the acute seizure period. Taken together, the present results suggest that inflammation in the hippocampus, caused predominantly by TNFα signaling, contributes to hyperexcitability and acute seizures after TMEV infection. Pharmacotherapies designed to suppress TNFR1-mediated or augment TNFR2-mediated effects of TNFα may provide antiseizure and disease-modifying effects after central nervous system infection.

Cerebrospinal fluid neopterin: an informative biomarker of central nervous system immune activation in HIV-1 infection.

PubMed

Hagberg, Lars; Cinque, Paola; Gisslen, Magnus; Brew, Bruce J; Spudich, Serena; Bestetti, Arabella; Price, Richard W; Fuchs, Dietmar

2010-06-03

HIV-1 invades the central nervous system (CNS) in the context of acute infection, persists thereafter in the absence of treatment, and leads to chronic intrathecal immunoactivation that can be measured by the macrophage activation marker, neopterin, in cerebrospinal fluid (CSF). In this review we describe our experience with CSF neopterin measurements in 382 untreated HIV-infected patients across the spectrum of immunosuppression and HIV-related neurological diseases, in 73 untreated AIDS patients with opportunistic CNS infections, and in 233 treated patients.In untreated patients, CSF neopterin concentrations are almost always elevated and increase progressively as immunosuppression worsens and blood CD4 cell counts fall. However, patients with HIV dementia exhibit particularly high CSF neopterin concentrations, above those of patients without neurological disease, though patients with CNS opportunistic infections, including CMV encephalitis and cryptococcal meningitis, also exhibit high levels of CSF neopterin. Combination antiretroviral therapy, with its potent effect on CNS HIV infection and CSF HIV RNA, mitigates both intrathecal immunoactivation and lowers CSF neopterin. However, despite suppression of plasma and CSF HIV RNA to below the detection limits of clinical assays (<50 copies HIV RNA/mL), CSF neopterin often remains mildly elevated, indicating persistent low-level intrathecal immune activation and raising the important questions of whether this elevation is driven by continued CNS infection and whether it causes continued indolent CNS injury.Although nonspecific, CSF neopterin can serve as a useful biomarker in the diagnosis of HIV dementia in the setting of confounding conditions, in monitoring the CNS inflammatory effects of antiretroviral treatment, and give valuable information to the cause of ongoing brain injury.

Hippocampal TNFα Signaling Contributes to Seizure Generation in an Infection-Induced Mouse Model of Limbic Epilepsy

PubMed Central

Patel, Dipan C.; Wallis, Glenna; Dahle, E. Jill; McElroy, Pallavi B.; Thomson, Kyle E.; West, Peter J.; Smeal, Roy M.; Patel, Manisha; Fujinami, Robert S.; White, H. Steve

2017-01-01

Abstract Central nervous system infection can induce epilepsy that is often refractory to established antiseizure drugs. Previous studies in the Theiler’s murine encephalomyelitis virus (TMEV)-induced mouse model of limbic epilepsy have demonstrated the importance of inflammation, especially that mediated by tumor necrosis factor-α (TNFα), in the development of acute seizures. TNFα modulates glutamate receptor trafficking via TNF receptor 1 (TNFR1) to cause increased excitatory synaptic transmission. Therefore, we hypothesized that an increase in TNFα signaling after TMEV infection might contribute to acute seizures. We found a significant increase in both mRNA and protein levels of TNFα and the protein expression ratio of TNF receptors (TNFR1:TNFR2) in the hippocampus, a brain region most likely involved in seizure initiation, after TMEV infection, which suggests that TNFα signaling, predominantly through TNFR1, may contribute to limbic hyperexcitability. An increase in hippocampal cell-surface glutamate receptor expression was also observed during acute seizures. Although pharmacological inhibition of TNFR1-mediated signaling had no effect on acute seizures, several lines of genetically modified animals deficient in either TNFα or TNFRs had robust changes in seizure incidence and severity after TMEV infection. TNFR2–/– mice were highly susceptible to developing acute seizures, suggesting that TNFR2-mediated signaling may provide beneficial effects during the acute seizure period. Taken together, the present results suggest that inflammation in the hippocampus, caused predominantly by TNFα signaling, contributes to hyperexcitability and acute seizures after TMEV infection. Pharmacotherapies designed to suppress TNFR1-mediated or augment TNFR2-mediated effects of TNFα may provide antiseizure and disease-modifying effects after central nervous system infection. PMID:28497109

Alcohol intake alters immune responses and promotes CNS viral persistence in mice.

PubMed

Loftis, Jennifer M; Taylor, Jonathan; Raué, Hans-Peter; Slifka, Mark K; Huang, Elaine

2016-10-01

Chronic hepatitis C virus (HCV) infection leads to progressive liver disease and is associated with a variety of extrahepatic effects, including central nervous system (CNS) damage and neuropsychiatric impairments. Alcohol abuse can exacerbate these adverse effects on brain and behavior, but the molecular mechanisms are not well understood. This study investigated the role of alcohol in regulating viral persistence and CNS immunopathology in mice infected with lymphocytic choriomeningitis virus (LCMV), a model for HCV infections in humans. Female and male BALB/c mice (n=94) were exposed to alcohol (ethanol; EtOH) and water (or water only) using a two-bottle choice paradigm, followed one week later by infection with either LCMV clone 13 (causes chronic infection similar to chronic HCV), LCMV Armstrong (causes acute infection), or vehicle. Mice were monitored for 60days post-infection and continued to receive 24-h access to EtOH and water. Animals infected with LCMV clone 13 drank more EtOH, as compared to those with an acute or no viral infection. Six weeks after infection with LCMV clone 13, mice with EtOH exposure evidenced higher serum viral titers, as compared to mice without EtOH exposure. EtOH intake was also associated with reductions in virus-specific CD8(+) T cell frequencies (particularly CD11a(hi) subsets) and evidence of persistent CNS viremia in chronically infected mice. These findings support the hypothesis that EtOH use and chronic viral infection can result in combined toxic effects accelerating CNS damage and neuropsychiatric dysfunction and suggest that examining the role of EtOH in regulating viral persistence and CNS immunopathology in mice infected with LCMV can lead to a more comprehensive understanding of comorbid alcohol use disorder and chronic viral infection. Published by Elsevier B.V.

Moraxella Catarrhalis: A Common Cause of Childhood Illnesses

MedlinePlus

... Life Family Life Family Life Medical Home Family Dynamics Media Work & Play Getting Involved in Your Community ... and Urinary Tract Glands & Growth Head Neck & Nervous System Heart Infections Learning Disabilities Obesity Orthopedic Prevention Sexually ...

Alternative Entry Receptors for Herpes Simplex Virus and Their Roles in Disease

PubMed Central

Taylor, Joann M.; Lin, Erick; Susmarski, Nanette; Yoon, Miri; Zago, Anna; Ware, Carl F.; Pfeffer, Klaus; Miyoshi, Jun; Takai, Yoshimi; Spear, Patricia G.

2007-01-01

SUMMARY Either herpesvirus entry mediator (HVEM, TNFRSF14) or nectin-1 (PVRL1) is sufficient for herpes simplex virus (HSV) infection of cultured cells. The contribution of individual receptors to infection in vivo and to disease is less clear. To assess this, Tnfrsf14 −/− and/or Pvrl1 −/− mice were challenged intravaginally with HSV-2. Infection of the vaginal epithelium occurred in the absence of either HVEM or nectin-1, but was virtually undetectable when both receptors were absent, indicating that either HVEM or nectin-1 was necessary. Absence of nectin-1 (but not HVEM) reduced efficiency of infection of the vaginal epithelium and viral spread to the nervous system, attenuating neurological disease and preventing external lesion development. While nectin-1 proved not to be essential for infection of the nervous system, it is required for the full manifestations of disease. This study illustrates the value of mutant mice for understanding receptor contributions to disease caused by a human virus. PMID:18005714

Emergency medical care in developing countries: is it worthwhile?

PubMed Central

Razzak, Junaid A.; Kellermann, Arthur L.

2002-01-01

Prevention is a core value of any health system. Nonetheless, many health problems will continue to occur despite preventive services. A significant burden of diseases in developing countries is caused by time-sensitive illnesses and injuries, such as severe infections, hypoxia caused by respiratory infections, dehydration caused by diarrhoea, intentional and unintentional injuries, postpartum bleeding, and acute myocardial infarction. The provision of timely treatment during life-threatening emergencies is not a priority for many health systems in developing countries. This paper reviews evidence indicating the need to develop and/or strengthen emergency medical care systems in these countries. An argument is made for the role of emergency medical care in improving the health of populations and meeting expectations for access to emergency care. We consider emergency medical care in the community, during transportation, and at first-contact and regional referral facilities. Obstacles to developing effective emergency medical care include a lack of structural models, inappropriate training foci, concerns about cost, and sustainability in the face of a high demand for services. A basic but effective level of emergency medical care responds to perceived and actual community needs and improves the health of populations. PMID:12481213

Role of capsule and suilysin in mucosal infection of complement-deficient mice with Streptococcus suis.

PubMed

Seitz, Maren; Beineke, Andreas; Singpiel, Alena; Willenborg, Jörg; Dutow, Pavel; Goethe, Ralph; Valentin-Weigand, Peter; Klos, Andreas; Baums, Christoph G

2014-06-01

Virulent Streptococcus suis serotype 2 strains are invasive extracellular bacteria causing septicemia and meningitis in piglets and humans. One objective of this study was to elucidate the function of complement in innate immune defense against S. suis. Experimental infection of wild-type (WT) and C3(-/-) mice demonstrated for the first time that the complement system protects naive mice against invasive mucosal S. suis infection. S. suis WT but not an unencapsulated mutant caused mortality associated with meningitis and other pathologies in C3(-/-) mice. The capsule contributed also substantially to colonization of the upper respiratory tract. Experimental infection of C3(-/-) mice with a suilysin mutant indicated that suilysin expression facilitated an early disease onset and the pathogenesis of meningitis. Flow cytometric analysis revealed C3 antigen deposition on the surface of ca. 40% of S. suis WT bacteria after opsonization with naive WT mouse serum, although to a significantly lower intensity than on the unencapsulated mutant. Ex vivo multiplication in murine WT and C3(-/-) blood depended on capsule but not suilysin expression. Interestingly, S. suis invasion of inner organs was also detectable in C5aR(-/-) mice, suggesting that chemotaxis and activation of immune cells via the anaphylatoxin receptor C5aR is, in addition to opsonization, a further important function of the complement system in defense against mucosal S. suis infection. In conclusion, we unequivocally demonstrate here the importance of complement against mucosal S. suis serotype 2 infection and that the capsule of this pathogen is also involved in escape from complement-independent immunity.

The role of Candida albicans AP-1 protein against host derived ROS in in vivo models of infection.

PubMed

Jain, Charu; Pastor, Kelly; Gonzalez, Arely Y; Lorenz, Michael C; Rao, Reeta P

2013-01-01

Candida albicans is a major fungal pathogen of humans, causing mucosal infections that are difficult to eliminate and systemic infections that are often lethal primarily due to defects in the host's innate status. Here we demonstrate the utility of Caenorhabditis elegans, a model host to study innate immunity, by exploring the role of reactive oxygen species (ROS) as a critical innate response against C. albicans infections. Much like a human host, the nematode's innate immune response is activated to produce ROS in response to fungal infection. We use the C. albicans cap1 mutant, which is susceptible to ROS, as a tool to dissect this physiological innate immune response and show that cap1 mutants fail to cause disease and death, except in bli-3 mutant worms that are unable to produce ROS because of a defective NADPH oxidase. We further validate the ROS-mediated host defense mechanism in mammalian phagocytes by demonstrating that chemical inhibition of the NADPH oxidase in cultured macrophages enables the otherwise susceptible cap1 mutant to resists ROS-mediated phagolysis. Loss of CAP1 confers minimal attenuation of virulence in a disseminated mouse model, suggesting that CAP1-independent mechanisms contribute to pathogen survival in vivo. Our findings underscore a central theme in the process of infection-the intricate balance between the virulence strategies employed by C. albicans and the host's innate immune system and validates C. elegans as a simple model host to dissect this balance at the molecular level.

Transcriptome analysis of Vibrio parahaemolyticus in type III secretion system 1 inducing conditions

PubMed Central

Nydam, Seth D.; Shah, Devendra H.; Call, Douglas R.

2014-01-01

Vibrio parahaemolyticus is an emerging bacterial pathogen capable of causing inflammatory gastroenteritis, wound infections, and septicemia. As a food-borne illness, infection is most frequently associated with the consumption of raw or undercooked seafood, particularly shellfish. It is the primary cause of Vibrio-associated food-borne illness in the United States and the leading cause of food-borne illness in Japan. The larger of its two chromosomes harbors a set of genes encoding type III section system 1 (T3SS1), a virulence factor present in all V. parahaemolyticus strains that is similar to the Yersinia ysc T3SS. T3SS1 translocates effector proteins into eukaryotic cells where they induce changes to cellular physiology and modulate host-pathogen interactions. T3SS1 is also responsible for cytotoxicity toward several different cultured cell lines as well as mortality in a mouse model. Herein we used RNA-seq to obtain global transcriptome patterns of V. parahaemolyticus under conditions that either induce [growth in Dulbecco's Modified Eagle Medium (DMEM) media, in trans expression of transcriptional regulator exsA] or repress T3SS1 expression (growth in LB-S media, in trans exsD expression) and during infection of HeLa cells over time. Comparative transcriptomic analysis demonstrated notable differences in the expression patterns under inducing conditions and was also used to generate an expression profile of V. parahaemolyticus during infection of HeLa cells. In addition, we identified several new genes that are associated with T3SS1 expression and may warrant further study. PMID:24478989

Type-1 angiotensin receptor signaling in central nervous system myeloid cells is pathogenic during fatal alphavirus encephalitis in mice.

PubMed

Blakely, Pennelope K; Huber, Amanda K; Irani, David N

2016-08-25

Alphaviruses can cause fatal encephalitis in humans. Natural infections occur via the bite of infected mosquitos, but aerosol transmissibility makes some of these viruses potential bioterrorism agents. Central nervous system (CNS) host responses contribute to alphavirus pathogenesis in experimental models and are logical therapeutic targets. We investigated whether reactive oxygen species (ROS) generated by nicotinamide adenine dinucleotide phosphate (NADPH) oxidase (Nox) activity within the CNS contributes to fatal alphavirus encephalitis in mice. Infected animals were treated systemically with the angiotensin receptor-blocking drug, telmisartan, given its ability to cross the blood-brain barrier, selectively block type-1 angiotensin receptors (AT1R), and inhibit Nox-derived ROS production in vascular smooth muscle and other extraneural tissues. Clinical, virological, biochemical, and histopathological outcomes were followed over time. The importance of the angiotensin II (Ang II)/AT1R axis in disease pathogenesis was confirmed by demonstrating increased Ang II levels in the CNS following infection, enhanced disease survival when CNS Ang II production was suppressed, increased AT1R expression on microglia and tissue-infiltrating myeloid cells, and enhanced disease survival in AT1R-deficient mice compared to wild-type (WT) controls. Systemic administration of telmisartan protected WT mice from lethal encephalitis caused by two different alphaviruses in a dose-dependent manner without altering virus replication or exerting any anti-inflammatory effects in the CNS. Infection triggered up-regulation of multiple Nox subunits in the CNS, while drug treatment inhibited local Nox activity, ROS production, and oxidative neuronal damage. Telmisartan proved ineffective in Nox-deficient mice, demonstrating that this enzyme is its main target in this experimental setting. Nox-derived ROS, likely arising from CNS myeloid cells triggered by AT1R signaling, are pathogenic during fatal alphavirus encephalitis in mice. Systemically administered telmisartan at non-hypotensive doses targets Nox activity in the CNS to exert a neuroprotective effect. Disruption of this pathway may have broader implications for the treatment of related infections as well as for other CNS diseases driven by oxidative injury.

Neuroinvasion and Inflammation in Viral Central Nervous System Infections

PubMed Central

Schroten, Horst

2016-01-01

Neurotropic viruses can cause devastating central nervous system (CNS) infections, especially in young children and the elderly. The blood-brain barrier (BBB) and the blood-cerebrospinal fluid barrier (BCSFB) have been described as relevant sites of entry for specific viruses as well as for leukocytes, which are recruited during the proinflammatory response in the course of CNS infection. In this review, we illustrate examples of established brain barrier models, in which the specific reaction patterns of different viral families can be analyzed. Furthermore, we highlight the pathogen specific array of cytokines and chemokines involved in immunological responses in viral CNS infections. We discuss in detail the link between specific cytokines and chemokines and leukocyte migration profiles. The thorough understanding of the complex and interrelated inflammatory mechanisms as well as identifying universal mediators promoting CNS inflammation is essential for the development of new diagnostic and treatment strategies. PMID:27313404

Mucosal immunity in the female genital tract, HIV/AIDS.

PubMed

Reis Machado, Juliana; da Silva, Marcos Vinícius; Cavellani, Camila Lourencini; dos Reis, Marlene Antônia; Monteiro, Maria Luiza Gonçalves dos Reis; Teixeira, Vicente de Paula Antunes; Miranda Corrêa, Rosana Rosa

2014-01-01

Mucosal immunity consists of innate and adaptive immune responses which can be influenced by systemic immunity. Despite having been the subject of intensive studies, it is not fully elucidated what exactly occurs after HIV contact with the female genital tract mucosa. The sexual route is the main route of HIV transmission, with an increased risk of infection in women compared to men. Several characteristics of the female genital tract make it suitable for inoculation, establishment of infection, and systemic spread of the virus, which causes local changes that may favor the development of infections by other pathogens, often called sexually transmitted diseases (STDs). The relationship of these STDs with HIV infection has been widely studied. Here we review the characteristics of mucosal immunity of the female genital tract, its alterations due to HIV/AIDS, and the characteristics of coinfections between HIV/AIDS and the most prevalent STDs.

Mucosal Immunity in the Female Genital Tract, HIV/AIDS

PubMed Central

Reis Machado, Juliana; da Silva, Marcos Vinícius; Cavellani, Camila Lourencini; Antônia dos Reis, Marlene; Monteiro, Maria Luiza Gonçalves dos Reis; Teixeira, Vicente de Paula Antunes; Rosa Miranda Corrêa, Rosana

2014-01-01

Mucosal immunity consists of innate and adaptive immune responses which can be influenced by systemic immunity. Despite having been the subject of intensive studies, it is not fully elucidated what exactly occurs after HIV contact with the female genital tract mucosa. The sexual route is the main route of HIV transmission, with an increased risk of infection in women compared to men. Several characteristics of the female genital tract make it suitable for inoculation, establishment of infection, and systemic spread of the virus, which causes local changes that may favor the development of infections by other pathogens, often called sexually transmitted diseases (STDs). The relationship of these STDs with HIV infection has been widely studied. Here we review the characteristics of mucosal immunity of the female genital tract, its alterations due to HIV/AIDS, and the characteristics of coinfections between HIV/AIDS and the most prevalent STDs. PMID:25313360

Bacterial antibiotic resistance, animal agriculture, and human health: no simple answer at the interface of three complex systems

USDA-ARS?s Scientific Manuscript database

Infectious disease is the second-leading cause of death worldwide and the third-leading cause of death in the United States (US) (Spellberg et al., 2008). The therapeutic use of antibiotics to treat bacterial infections is often cited as the most important medical innovation of the 20th century, and...

Tetraodon nigroviridis as a nonlethal model of infectious spleen and kidney necrosis virus (ISKNV) infection

DOE Office of Scientific and Technical Information (OSTI.GOV)

Xu Xiaopeng; Huang Lichao; Weng Shaoping

Infectious spleen and kidney necrosis virus (ISKNV) is the type species of the genus Megalocytivirus, family Iridoviridae. We have previously established a high mortality ISKNV infection model of zebrafish (Danio rerio). In this study, a nonlethal Tetraodon nigroviridis model of ISKNV infection was established. ISKNV infection did not cause lethal disease in Tetraodon but could infect almost all the organs of this species. Electron microscopy showed ISKNV particles were present in infected tissues. Immunofluorescence and quantitative real-time PCR analysis showed that nearly all the virions and infected cells were cleared at 14 d postinfection. The expression profiles of interferon-{gamma} andmore » tumor necrosis factor-{alpha} gene in response to ISKNV infection were significantly different in Tetraodon and zebrafish. The establishment of the nonlethal Tetraodon model of ISKNV infection can offer a valuable tool complementary to the zebrafish infection model for studying megalocytivirus disease, fish immune systems, and viral tropism.« less

Genital Herpes: Insights into Sexually Transmitted Infectious Disease

PubMed Central

Jaishankar, Dinesh; Shukla, Deepak

2016-01-01

Etiology, transmission and protection: Herpes simplex virus-2 (HSV-2) is a leading cause of sexually transmitted infections with recurring manifestations throughout the lifetime of infected hosts. Currently no effective vaccines or prophylactics exist that provide complete protection or immunity from the virus, which is endemic throughout the world. Pathology/Symptomatology: Primary and recurrent infections result in lesions and inflammation around the genital area and the latter accounts for majority of genital herpes instances. Immunocompromised patients including neonates are susceptible to additional systemic infections including debilitating consequences of nervous system inflammation. Epidemiology, incidence and prevalence: More than 500 million people are infected worldwide and most reported cases involve the age groups between 16-40 years, which coincides with an increase in sexual activity among this age group. While these numbers are an estimate, the actual numbers may be underestimated as many people are asymptomatic or do not report the symptoms. Treatment and curability: Currently prescribed medications, mostly nucleoside analogs, only reduce the symptoms caused by an active infection, but do not eliminate the virus or reduce latency. Therefore, no cure exists against genital herpes and infected patients suffer from periodic recurrences of disease symptoms for their entire lives. Molecular mechanisms of infection: The last few decades have generated many new advances in our understanding of the mechanisms that drive HSV infection. The viral entry receptors such as nectin-1 and HVEM have been identified, cytoskeletal signaling and membrane structures such as filopodia have been directly implicated in viral entry, host motor proteins and their viral ligands have been shown to facilitate capsid transport and many host and HSV proteins have been identified that help with viral replication and pathogenesis. New understanding has emerged on the role of autophagy and other innate immune mechanisms that are subverted to enhance HSV pathogenesis. This review summarizes our current understanding of HSV-2 and associated diseases and available or upcoming new treatments. PMID:28357380

Genital Herpes: Insights into Sexually Transmitted Infectious Disease.

PubMed

Jaishankar, Dinesh; Shukla, Deepak

2016-06-27

Etiology, transmission and protection: Herpes simplex virus-2 (HSV-2) is a leading cause of sexually transmitted infections with recurring manifestations throughout the lifetime of infected hosts. Currently no effective vaccines or prophylactics exist that provide complete protection or immunity from the virus, which is endemic throughout the world. Pathology/Symptomatology: Primary and recurrent infections result in lesions and inflammation around the genital area and the latter accounts for majority of genital herpes instances. Immunocompromised patients including neonates are susceptible to additional systemic infections including debilitating consequences of nervous system inflammation. Epidemiology, incidence and prevalence: More than 500 million people are infected worldwide and most reported cases involve the age groups between 16-40 years, which coincides with an increase in sexual activity among this age group. While these numbers are an estimate, the actual numbers may be underestimated as many people are asymptomatic or do not report the symptoms. Treatment and curability: Currently prescribed medications, mostly nucleoside analogs, only reduce the symptoms caused by an active infection, but do not eliminate the virus or reduce latency. Therefore, no cure exists against genital herpes and infected patients suffer from periodic recurrences of disease symptoms for their entire lives. Molecular mechanisms of infection: The last few decades have generated many new advances in our understanding of the mechanisms that drive HSV infection. The viral entry receptors such as nectin-1 and HVEM have been identified, cytoskeletal signaling and membrane structures such as filopodia have been directly implicated in viral entry, host motor proteins and their viral ligands have been shown to facilitate capsid transport and many host and HSV proteins have been identified that help with viral replication and pathogenesis. New understanding has emerged on the role of autophagy and other innate immune mechanisms that are subverted to enhance HSV pathogenesis. This review summarizes our current understanding of HSV-2 and associated diseases and available or upcoming new treatments.

Infections in liver and lung transplant recipients: a national prospective cohort.

PubMed

Gagliotti, Carlo; Morsillo, Filomena; Moro, Maria Luisa; Masiero, Lucia; Procaccio, Francesco; Vespasiano, Francesca; Pantosti, Annalisa; Monaco, Monica; Errico, Giulia; Ricci, Andrea; Grossi, Paolo; Nanni Costa, Alessandro

2018-03-01

Infections are a major complication of solid organ transplants (SOTs). This study aimed to describe recipients' characteristics, and the frequency and etiology of infections and transplant outcome in liver and lung SOTs, and to investigate exposures associated to infection and death in liver transplant recipients. The study population included recipients of SOTs performed in Italy during a 1-year period in ten Italian lung transplant units and eight liver transplant units. Data on comorbidities, infections, retransplantation, and death were prospectively collected using a web-based system, with a 6-month follow-up. The cumulative incidence of infection was 31.7% and 47.8% in liver and lung transplants, respectively, with most infections occurring within the first month after transplantation. Gram-negatives, which were primarily multidrug-resistant, were the most frequent cause of infection. Death rates were 0.42 per 1000 recipient-days in liver transplants and 1.41 per 1000 recipient-days in lung transplants. Infection after SOT in adult liver recipients is associated to an increased risk of death (OR = 13.25; p-value < 0.001). Given the frequency of infection caused by multidrug-resistant microorganisms in SOT recipients in Italy and the heavy impact of infections on the transplant outcome, the reinforcement of surveillance and control activities to prevent the transmission of multidrug-resistant microorganisms in SOT recipients represents a priority. The implementation of the study protocol in liver and lung transplant units and the sharing of results have increased the awareness about the threat due to antimicrobial resistance in the country.

Cytoplasmic Copper Detoxification in Salmonella Can Contribute to SodC Metalation but Is Dispensable during Systemic Infection

PubMed Central

Fenlon, Luke A.

2017-01-01

ABSTRACT Salmonella enterica serovar Typhimurium is a leading cause of foodborne disease worldwide. Severe infections result from the ability of S. Typhimurium to survive within host immune cells, despite being exposed to various host antimicrobial factors. SodCI, a copper-zinc-cofactored superoxide dismutase, is required to defend against phagocytic superoxide. SodCII, an additional periplasmic superoxide dismutase, although produced during infection, does not function in the host. Previous studies suggested that CueP, a periplasmic copper binding protein, facilitates acquisition of copper by SodCII. CopA and GolT, both inner membrane ATPases that pump copper from the cytoplasm to the periplasm, are a source of copper for CueP. Using in vitro SOD assays, we found that SodCI can also utilize CueP to acquire copper. However, both SodCI and SodCII have a significant fraction of activity independent of CueP and cytoplasmic copper export. We utilized a series of mouse competition assays to address the in vivo role of CueP-mediated SodC activation. A copA golT cueP triple mutant was equally as competitive as the wild type, suggesting that sufficient SodCI is active to defend against phagocytic superoxide independent of CueP and cytoplasmic copper export. We also confirmed that a strain containing a modified SodCII, which is capable of complementing a sodCI deletion, was fully virulent in a copA golT cueP background competed against the wild type. These competitions also address the potential impact of cytoplasmic copper toxicity within the phagosome. Our data suggest that Salmonella does not encounter inhibitory concentrations of copper during systemic infection. IMPORTANCE Salmonella is a leading cause of gastrointestinal disease worldwide. In severe cases, Salmonella can cause life-threatening systemic infections, particularly in very young children, the elderly, or people who are immunocompromised. To cause disease, Salmonella must survive the hostile environment inside host immune cells, a location in which most bacteria are killed. Our work examines how one particular metal, copper, is acquired by Salmonella to activate a protein important for survival within immune cells. At high levels, copper itself can inhibit Salmonella. Using a strain of Salmonella that cannot detoxify intracellular copper, we also addressed the in vivo role of copper as an antimicrobial agent. PMID:28924031

Cytoplasmic Copper Detoxification in Salmonella Can Contribute to SodC Metalation but Is Dispensable during Systemic Infection.

PubMed

Fenlon, Luke A; Slauch, James M

2017-12-15

Salmonella enterica serovar Typhimurium is a leading cause of foodborne disease worldwide. Severe infections result from the ability of S Typhimurium to survive within host immune cells, despite being exposed to various host antimicrobial factors. SodCI, a copper-zinc-cofactored superoxide dismutase, is required to defend against phagocytic superoxide. SodCII, an additional periplasmic superoxide dismutase, although produced during infection, does not function in the host. Previous studies suggested that CueP, a periplasmic copper binding protein, facilitates acquisition of copper by SodCII. CopA and GolT, both inner membrane ATPases that pump copper from the cytoplasm to the periplasm, are a source of copper for CueP. Using in vitro SOD assays, we found that SodCI can also utilize CueP to acquire copper. However, both SodCI and SodCII have a significant fraction of activity independent of CueP and cytoplasmic copper export. We utilized a series of mouse competition assays to address the in vivo role of CueP-mediated SodC activation. A copA golT cueP triple mutant was equally as competitive as the wild type, suggesting that sufficient SodCI is active to defend against phagocytic superoxide independent of CueP and cytoplasmic copper export. We also confirmed that a strain containing a modified SodCII, which is capable of complementing a sodCI deletion, was fully virulent in a copA golT cueP background competed against the wild type. These competitions also address the potential impact of cytoplasmic copper toxicity within the phagosome. Our data suggest that Salmonella does not encounter inhibitory concentrations of copper during systemic infection. IMPORTANCE Salmonella is a leading cause of gastrointestinal disease worldwide. In severe cases, Salmonella can cause life-threatening systemic infections, particularly in very young children, the elderly, or people who are immunocompromised. To cause disease, Salmonella must survive the hostile environment inside host immune cells, a location in which most bacteria are killed. Our work examines how one particular metal, copper, is acquired by Salmonella to activate a protein important for survival within immune cells. At high levels, copper itself can inhibit Salmonella Using a strain of Salmonella that cannot detoxify intracellular copper, we also addressed the in vivo role of copper as an antimicrobial agent. Copyright © 2017 American Society for Microbiology.

[Potential neurocognitive consequences of infection by human respiratory syncytial virus].

PubMed

Flores, Juan Carlos; Bohmwald, Karen; Espinoza, Janyra; Jara, Crlstlna; Peña, Marcela; Hoyos-Bachiloglu, Rodrigo; Iturriaga, Carolina; Kalergis, Alexis M; Borzutzky, Arturo

2016-10-01

Human respiratory syncytial virus (RSV) infection remains as a major cause of morbidity and mortality among pediatric population. Immune response is poor and unable to establish a long term effective protection against this virus. Of particular interest has been the description of extrapulmonary manifestations of RSV infection in liver, kidney, endocrine system, heart and brain, associated to infection of peripheral blood. In the central nervous system (CNS), recent studies in animals have suggested long term neurocognitive impairment due to a direct damage from the virus. This was prevented in rats by a recombinant BCG vaccine expressing a nucleoprotein N of RSV that produces an effective immune response against the virus, not allowing its dissemination to the CNS. These findings in animal models highlight the importance of conducting more specific studies in children affected with severe infection by RSV. Therefore, our group is currently conducting an assessment of the possible long-term cognitive impairment in children under 2 years. The results of this study could be a strong argument to continue looking for an effective method for protecting against RSV infection.

Interleukin-27 Early Impacts Leishmania infantum Infection in Mice and Correlates with Active Visceral Disease in Humans

PubMed Central

Pérez-Cabezas, Begoña; Cecílio, Pedro; Robalo, Ana Luisa; Silvestre, Ricardo; Carrillo, Eugenia; Moreno, Javier; San Martín, Juan V.; Vasconcellos, Rita; Cordeiro-da-Silva, Anabela

2016-01-01

The complexity of Leishmania–host interactions, one of the main leishmaniasis issues, is yet to be fully understood. We detected elevated IL-27 plasma levels in European patients with active visceral disease caused by Leishmania infantum, which returned to basal levels after successful treatment, suggesting this cytokine as a probable infection mediator. We further addressed this hypothesis recurring to two classical susceptible visceral leishmaniasis mouse models. BALB/c, but not C57BL/6 mice, showed increased IL-27 systemic levels after infection, which was associated with an upregulation of IL-27p28 expression by dendritic cells and higher parasite burdens. Neutralization of IL-27 in acutely infected BALB/c led to decreased parasite burdens and a transient increase in IFN-γ+ splenic T cells, while administration of IL-27 to C57BL/6 promoted a local anti-inflammatory cytokine response at the site of infection and increased parasite loads. Overall, we show that, as in humans, BALB/c IL-27 systemic levels are infection dependently upregulated and may favor parasite installation by controlling inflammation. PMID:27867384

Oral innate immunity in HIV infection in HAART era

PubMed Central

Nittayananta, Wipawee; Tao, Renchuan; Jiang, Lanlan; Peng, Yuanyuan; Huang, Yuxiao

2015-01-01

Oral innate immunity, an important component in host defense and immune surveillance in the oral cavity, plays a crucial role in the regulation of oral health. As part of the innate immune system, epithelial cells lining oral mucosal surfaces provide not only a physical barrier but also produce different antimicrobial peptides, including human β-defensins (hBDs), secretory leukocyte protease inhibitor (SLPI), and various cytokines. These innate immune mediators help in maintaining oral homeostasis. When they are impaired either by local or systemic causes, various oral infections and malignancies may be developed. Human immunodeficiency virus (HIV) infection and other co-infections appear to have both direct and indirect effects on systemic and local innate immunity leading to the development of oral opportunistic infections and malignancies. Highly active antiretroviral therapy (HAART), the standard treatment of HIV infection contributed to a global reduction of HIV-associated oral lesions. However, prolonged treatment by HAART may lead to adverse effects on the oral innate immunity resulting in the relapse of oral lesions. This review article focused on the roles of oral innate immunity in HIV infection in HAART era. The following five key questions were addressed: 1) What are the roles of oral innate immunity in health and disease?, 2) What are the effects of HIV infection on oral innate immunity?, 3) What are the roles of oral innate immunity against other co-infections?, 4) What are the effects of HAART on oral innate immunity?, and 5) Is oral innate immunity enhanced by HAART? PMID:25639844