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1.
Infect Dis Now ; 51(3): 296-299, 2021 May.
Article in English | MEDLINE | ID: mdl-33495765

ABSTRACT

BACKGROUND: Systemic reactivation of herpesviruses may occur in intensive care unit (ICU) patients and is associated with morbidity and mortality. Data on severe Coronavirus disease-19 (COVID-19) and concomitant reactivation of herpesviruses are lacking. METHODS: We selected patients admitted to ICU for confirmed COVID-19 who underwent systematic testing for Epstein-Barr virus (EBV), cytomegalovirus (CMV) and human-herpes virus-6 (HHV-6) DNAemia while in the ICU. We retrospectively analysed frequency, timing, duration and co-occurrence of viral DNAemia. RESULTS: Thirty-four patients were included. Viremia with EBV, CMV, and HHV-6 was detected in 28 (82%), 5 (15%), and 7 (22%) patients, respectively. EBV reactivation occurred early after ICU admission and was associated with longer ICU length-of-stay. CONCLUSIONS: While in the ICU, critically ill patients with COVID-19 are prone to develop reactivations due to various types of herpesviruses.


Subject(s)
COVID-19/complications , Cytomegalovirus/physiology , Herpesvirus 4, Human/physiology , Herpesvirus 6, Human/physiology , Latent Infection/complications , Virus Activation , Adult , Aged , Aged, 80 and over , Critical Illness/epidemiology , Female , France/epidemiology , Humans , Incidence , Intensive Care Units , Male , Middle Aged , Retrospective Studies , SARS-CoV-2
2.
Virology ; 522: 271-280, 2018 09.
Article in English | MEDLINE | ID: mdl-30056354

ABSTRACT

Viral RNA (vRNA) is found in mice inoculated with coxsackievirus-B4E2 (CV-B4E2). The CV-B4E2 infection of murine spleen cells in vitro is enhanced with CV-B4E2-infected mouse serum. It has been investigated whether monocyte/macrophages were targets of CV-B4E2 in mice. vRNA has been detected in spleen and bone marrow of infected animals. The levels of vRNA were higher in CD14+ cells than in CD14- spleen cells and in F4/80- cells than in F4/80+ spleen cells. Meanwhile, CD14+ cells and F4/80- cells were more permissive to CV-B4E2 in vitro and the infection was enhanced when the virus was mixed with immune serum. While CV-B4E2 infected BMDM cultures (98% F4/80+); however, the immune serum did not enhance the infection. In conclusion, CV-B4E2 infects monocytes (CD14+, F4/80-) and macrophages (CD14+, F4/80+) in vivo and immune serum can enhance the in vitro infection of these cells arising out of the spleen.


Subject(s)
Coxsackievirus Infections/virology , Enterovirus B, Human/growth & development , Macrophages/virology , Monocytes/virology , Animals , Antibody-Dependent Enhancement , Bone Marrow/virology , Disease Models, Animal , Mice , RNA, Viral/analysis , Spleen/virology
4.
Eur J Clin Microbiol Infect Dis ; 36(8): 1433-1441, 2017 Aug.
Article in English | MEDLINE | ID: mdl-28421309

ABSTRACT

Shiga toxin (Stx)-producing Escherichia coli (STECs) cause non-bloody diarrhea, hemorrhagic colitis, and hemolytic uremic syndrome, and are the primary cause of acute renal failure in children worldwide. This study investigated the correlation of genetic makeup of STEC strains as revealed by DNA microarray to clinical symptoms and the duration of STEC shedding. All STEC isolated (n = 96) from patients <10 years of age in Jönköping County, Sweden from 2003 to 2015 were included. Isolates were characterized by DNA microarray, including almost 280 genes. Clinical data were collected through a questionnaire and by reviewing medical records. Of the 96 virulence genes (including stx) in the microarray, 62 genes were present in at least one isolate. Statistically significant differences in prevalence were observed for 21 genes when comparing patients with bloody diarrhea (BD) and with non-bloody stool (18 of 21 associated with BD). Most genes encode toxins (e.g., stx2 alleles, astA, toxB), adhesion factors (i.e. espB_O157, tir, eae), or secretion factors (e.g., espA, espF, espJ, etpD, nleA, nleB, nleC, tccP). Seven genes were associated with prolonged stx shedding; the presence of three genes (lpfA, senB, and stx1) and the absence of four genes (espB_O157, espF, astA, and intI1). We found STEC genes that might predict severe disease outcome already at diagnosis. This can be used to develop diagnostic tools for risk assessment of disease outcome. Furthermore, genes associated with the duration of stx shedding were detected, enabling a possible better prediction of length of STEC carriage after infection.


Subject(s)
Bacterial Shedding , Escherichia coli Infections/microbiology , Escherichia coli Infections/pathology , Microarray Analysis , Shiga-Toxigenic Escherichia coli/classification , Shiga-Toxigenic Escherichia coli/genetics , Virulence Factors/genetics , Child , Child, Preschool , Genetic Variation , Humans , Infant , Shiga-Toxigenic Escherichia coli/isolation & purification , Sweden
5.
Virulence ; 8(7): 1229-1244, 2017 10 03.
Article in English | MEDLINE | ID: mdl-28112573

ABSTRACT

INTRODUCTION: Although known as cytolytic viruses, group B coxackieviruses (CVB) are able to establish a persistent infection in vitro and in vivo. Viral persistence has been reported as a key mechanism in the pathogenesis of CVB-associated chronic diseases such as type 1 diabetes (T1D). The impact of CVB4 persistence on human pancreas ductal-like cells was investigated. METHODS: A persistent CVB4 infection was established in ductal-like cells. PDX-1 expression, resistance to CVB4-induced lysis and CAR expression were evaluated. The profile of cellular microRNAs (miRNAs) was investigated through miRNA-sequencing. Viral phenotypic changes were examined, and genomic modifications were assessed by sequencing of the viral genome. RESULTS: The CVB4 persistence in ductal-like cells was productive, with continuous release of infectious particles. Persistently infected cells displayed a resistance to CVB4-induced lysis upon superinfection and expression of PDX-1 and CAR was decreased. These changes were maintained even after virus clearance. The patterns of cellular miRNA expression in mock-infected and in CVB4-persistently infected ductal-like cells were clearly different. The persistent infection-derived virus (PIDV) was still able to induce cytopathic effect but its plaques were smaller than the parental virus. Several mutations appeared in various PIDV genome regions, but amino acid substitutions did not affect the predicted site of interaction with CAR. CONCLUSION: Cellular and viral changes occur during persistent infection of human pancreas ductal-like cells with CVB4. The persistence of cellular changes even after virus clearance supports the hypothesis of a long-lasting impact of persistent CVB infection on the cells.


Subject(s)
Coxsackievirus Infections/virology , Enterovirus B, Human/physiology , Pancreatic Ducts/cytology , Pancreatic Ducts/virology , Cell Line, Tumor , Coxsackievirus Infections/genetics , Coxsackievirus Infections/metabolism , Enterovirus B, Human/genetics , Homeodomain Proteins/genetics , Homeodomain Proteins/metabolism , Humans , MicroRNAs/genetics , MicroRNAs/metabolism , Pancreas/metabolism , Pancreas/virology , Trans-Activators/genetics , Trans-Activators/metabolism , Virus Replication
6.
J Clin Virol ; 75: 60-3, 2016 Feb.
Article in English | MEDLINE | ID: mdl-26679224

ABSTRACT

We here report the case of a 30-year old man with a history of ulcerative colitis, who presented clinical and biological features compatible with a viral hepatitis. Initial serological results revealed the presence of IgM antibodies against many viruses, and the most likely diagnosis was viral hepatitis A. However, further investigations were performed and concluded to cytomegalovirus primary infection.


Subject(s)
Colitis, Ulcerative , Cytomegalovirus Infections , Cytomegalovirus , Immunoglobulin M/blood , Abdominal Pain , Adult , Antibodies, Viral/immunology , Colitis, Ulcerative/blood , Colitis, Ulcerative/complications , Colitis, Ulcerative/immunology , Colitis, Ulcerative/physiopathology , Cytomegalovirus Infections/complications , Cytomegalovirus Infections/diagnosis , Diagnosis, Differential , Fever , Hepatitis A/complications , Hepatitis A/diagnosis , Humans , Immunoglobulin M/immunology , Male , Serology
8.
Transpl Infect Dis ; 13(3): 259-65, 2011 Jun.
Article in English | MEDLINE | ID: mdl-21156011

ABSTRACT

Herpesvirus infections cause morbidity in lung transplant recipients. The study was conducted to investigate the incidence and impact of herpes simplex virus (HSV) and cytomegalovirus (CMV) detection in the respiratory tract (RT) of lung and heart-lung transplant recipients (LTR) during the postoperative phase. In a prospective cohort study, 91 LTR having at least 1 nasopharyngeal swab (NPS) sent for virus diagnostics were monitored for CMV and HSV detection in NPS during their post-transplant hospital stay on cardiothoracic surgery wards (median 4 weeks) by direct immunofluorescence testing for HSV, virus culture, and CMV and HSV polymerase chain reaction (PCR). Bronchoalveolar lavages (BALs) were analyzed with the same protocol except that HSV PCR was only performed on request. Risk factor analysis for the outcome '90-day mortality' was performed. Fifteen LTR had virus detection in NPS (16.5%): 9 had CMV, 5 had HSV, and 1 had both CMV and HSV. Four of 84 LTR had CMV detection in BAL (4.8%). Absence of CMV detection in NPS had a negative predictive value of 98.8% for absence of CMV detection in BAL. HSV DNA detection in NPS, especially if detected within 8 days after transplantation, was associated with 90-day mortality. In conclusion, detection of herpesviruses in the RT was clinically relevant and frequent, despite antiviral prophylaxis.


Subject(s)
Cytomegalovirus/isolation & purification , Heart Transplantation/adverse effects , Lung Transplantation/adverse effects , Respiratory Tract Infections/epidemiology , Respiratory Tract Infections/virology , Simplexvirus/isolation & purification , Adolescent , Adult , Aged , Child , Child, Preschool , Cohort Studies , Cytomegalovirus/genetics , Cytomegalovirus Infections/epidemiology , Cytomegalovirus Infections/virology , Female , Herpes Simplex/epidemiology , Herpes Simplex/mortality , Herpes Simplex/virology , Humans , Incidence , Infant , Male , Middle Aged , Polymerase Chain Reaction/methods , Respiratory Tract Infections/mortality , Respiratory Tract Infections/physiopathology , Simplexvirus/genetics , Young Adult
9.
Pneumologie ; 64(5): 291-9, 2010 May.
Article in German | MEDLINE | ID: mdl-20455176

ABSTRACT

Lower respiratory tract infections rank among the leading causes of morbidity and mortality worldwide. In clinical practice, especially in the care of severely ill patients, discrimination between tracheobronchial colonisation with potentially pathogenic microorganisms and infection is a common diagnostic challenge. While prompt antibiotic treatment is needed in critically ill patients with pneumonia, an inadequate use of antibiotics is the major cause for the emergence of drug-resistant microorganisms. The first part of this review provided a detailed overview of the currently available methods for the diagnosis of pulmonary infectious diseases. In the present second part of the manuscript, we focus upon methods and criteria for the differentiation between lower respiratory tract bacterial colonisation and lower respiratory tract infections, highlighting important pathogens.


Subject(s)
Respiratory Tract Infections/diagnosis , Anti-Bacterial Agents/therapeutic use , Antigens, Bacterial/immunology , Antigens, Viral/immunology , Bronchi/microbiology , Bronchi/virology , Diagnosis, Differential , Humans , Lung Diseases/diagnosis , Lung Diseases/microbiology , Lung Diseases/virology , Morbidity , Pulmonary Medicine/methods , Respiratory Tract Infections/epidemiology , Respiratory Tract Infections/mortality , Trachea/microbiology , Trachea/virology , Virus Diseases/drug therapy
10.
Pneumologie ; 64(8): 474-87, 2010 Aug.
Article in German | MEDLINE | ID: mdl-20491002

ABSTRACT

Lower respiratory tract infections play an important role in the ambulatory and hospital health-care sectors. State-of-the-art diagnoses of lower respiratory tract infections and methods to differentiate bacterial lower respiratory tract infections from colonisation have been described in the first two parts of this review series. The present article summarises current diagnostic methods and treatment indications for viral and fungal respiratory infections. These recommendations may guide clinicians in their decision to prescribe or withhold antibiotic therapies in daily clinical practice.


Subject(s)
Mycoses/diagnosis , Mycoses/therapy , Pulmonary Medicine/trends , Respiratory Tract Infections/diagnosis , Respiratory Tract Infections/therapy , Virus Diseases/diagnosis , Virus Diseases/therapy , Germany , Humans
11.
J Med Microbiol ; 58(Pt 3): 365-370, 2009 Mar.
Article in English | MEDLINE | ID: mdl-19208888

ABSTRACT

Nowadays, influenza antigen detection test kits are used most frequently to detect influenza A or B virus to establish the diagnosis of influenza rapidly and initiate appropriate therapy. This study was conducted to evaluate the performance of the actim Influenza A&B test (Medix Biochemica). Overall, 473 respiratory specimens were analysed in the actim Influenza A&B test and the results were compared with those from an RT-PCR assay; 461 of these samples originated from paediatric patients aged 7 weeks to 6.5 years either with influenza-related symptoms or from the intensive care unit, and 12 samples originated from adults with underlying lung or haematological diseases. Diagnosis of influenza A or B virus could be established using the actim Influenza A&B test (9/473 samples for influenza A virus and 6/473 for influenza B virus). RT-PCR revealed 23 patients with influenza virus (13/473 for influenza A virus and 10/473 for influenza B virus). The sensitivity and specificity of the actim Influenza A&B test were 65 and 100 % compared with the RT-PCR assay. However, 32 external quality assessment samples containing seven different strains of influenza A subtypes H1N1 and H3N2 and the avian H5N1 were detected correctly by the actim Influenza A&B test. No cross-reactivity to a range of bacterial, fungal and other viral pathogens was observed. In conclusion, the actim Influenza A&B test is reliable for positive results due to its high specificity. Nevertheless, negative results from this test need to be confirmed by a more sensitive assay because of the low sensitivity observed with diagnostic samples.


Subject(s)
Antigens, Viral/isolation & purification , Influenza A virus/isolation & purification , Influenza B virus/isolation & purification , Influenza, Human/diagnosis , Adolescent , Adult , Antibodies, Monoclonal , Child , Child, Preschool , Cross Reactions , DNA, Complementary/isolation & purification , DNA, Viral/isolation & purification , Humans , Infant , Influenza A virus/genetics , Influenza A virus/immunology , Influenza B virus/genetics , Influenza B virus/immunology , Influenza, Human/virology , Middle Aged , Prospective Studies , RNA, Viral/genetics , Reverse Transcriptase Polymerase Chain Reaction , Sensitivity and Specificity , Young Adult
12.
J Med Virol ; 80(3): 467-77, 2008 Mar.
Article in English | MEDLINE | ID: mdl-18205230

ABSTRACT

Rapid diagnosis of human herpesvirus primary infections or reactivations is facilitated by quantitative PCRs. Quantitative PCR assays with a standard thermal cycling profile permitting simultaneous detection of herpes simplex virus (HSV), varicella zoster virus (VZV), cytomegalovirus (CMV), Epstein-Barr virus (EBV), and human herpesvirus 6 (HHV6) DNA were developed and validated for diagnostic use. High specificity and sensitivity were achieved and the new PCR assays correlated well with commercial PCR assays. Twenty two thousand eight hundred sixty eight PCR tests were undertaken on specimens obtained from immunosuppressed patients. DNAemia was frequent with EBV (43.5%), HHV6 (32.4%), CMV (12.8%), and VZV (12.9%). As already described for EBV and CMV, high virus loads of HHV6 and VZV were associated with clinical symptoms and poor clinical outcome, for example, three of four patients with VZV virus loads >10(5) copies/ml died. A high proportion of lower respiratory specimens was positive for EBV- (38.8%), HHV6- (29.4%), and CMV-DNA (18.2%). For CMV, infection was confirmed in 66.7% of patients by virus isolation or positive pp65 antigenaemia. Differentiation of HHV6A, -B and HSV-1, -2 by melting curve analysis revealed that HHV6A and HSV-2 represented only 1.8% and 3.3% of all positive specimens, respectively. In conclusion, these results indicate significant improvements for the early diagnosis of primary infections or reactivations of five human herpesviruses especially in immunosuppressed patients. Detection of coinfections with multiple herpesviruses is facilitated. Quantitative results enable monitoring of virus load during antiviral therapy. A standard thermal cycling profile permits time and cost effective use in a routine diagnostic setting.


Subject(s)
DNA, Viral/analysis , Herpesviridae Infections/diagnosis , Herpesviridae Infections/virology , Herpesviridae/isolation & purification , Polymerase Chain Reaction/methods , Cytomegalovirus/isolation & purification , DNA, Viral/blood , DNA, Viral/cerebrospinal fluid , DNA, Viral/urine , Herpesvirus 3, Human/isolation & purification , Herpesvirus 4, Human/isolation & purification , Herpesvirus 6, Human/isolation & purification , Humans , Sensitivity and Specificity , Simplexvirus/isolation & purification
13.
Infection ; 35(4): 219-24, 2007 Jun.
Article in English | MEDLINE | ID: mdl-17646909

ABSTRACT

The recent unfortunate rabies transmissions through solid organ transplants of an infected donor in Germany required the initiation of a vaccination program to protect health care workers (HCWs) with close contact to rabies-infected patients. A systematic follow-up of adverse effects was initiated. Rabies postexposure prophylaxis (PEP) was started in 269 HCWs at four German hospitals. Pre-exposure prophylaxis (PreEP) was administered to 74 HCWs caring for an already diagnosed rabies patient. At each vaccination date, HCWs were interviewed for symptoms possibly representing adverse effects. Adverse effects of PEP and PrePEP were compared. Out of 269 HCWs, 216 were included for the investigation of adverse effects. Of these 216 HCWs, 114 (53%) individuals developed at least one systemic adverse effect. Incidences of tiredness (30.6%), malaise (26.4%), headache (26.9%), dizziness (14.8%), and chills (13.0%) declined in the course of PEP (p < 0.05), whereas incidences of fever (7.4%), paraesthesias (7.9%), arthralgias (1.9%), myalgias (4.2%), nausea (9.3%), diarrheas (2.8%) and vomiting (1.4%) did not. In 11 (5.1%) HCWs PEP was discontinued mostly due to adverse reactions (four suffered strong headaches, two HCWs meningeal irritations, two chills, one paraesthesia, one malaise, and one a rush). Systemic effects of PEP or PreEP did not differ significantly. Despite relatively high incidences of moderate severe adverse reactions rabies PEP is safe. Strong headache, tiredness, dizziness, and paraesthesias are the most important postvaccinal symptoms. Vaccinees suffering from adverse effects of PEP must be strongly encouraged to complete PEP, as it is to date the only protection against fatal rabies.


Subject(s)
Immunization, Passive/adverse effects , Mass Vaccination/adverse effects , Occupational Exposure , Rabies Vaccines/adverse effects , Rabies , Vaccination/adverse effects , Contact Tracing , Follow-Up Studies , Germany , Health Personnel , Humans , Immunization, Passive/methods , Infectious Disease Transmission, Patient-to-Professional , Mass Vaccination/methods , Prospective Studies , Rabies/immunology , Rabies/prevention & control , Transplants/virology
14.
Eur J Clin Microbiol Infect Dis ; 22(12): 720-5, 2003 Dec.
Article in English | MEDLINE | ID: mdl-14605944

ABSTRACT

The objective of this prospective study was to evaluate the clinical and laboratory parameters distinguishing viral from nonviral lower respiratory tract infection in elderly patients and to determine the yield of virological diagnostics in elderly patients with lower respiratory tract infection. The study was conducted in a 184-bed geriatric department in a university hospital during 4 winter months. All consecutive elderly persons admitted with a lower respiratory tract infection were included in the study. Clinical and laboratory parameters, a nasopharyngeal swab, and serological results for respiratory viruses were obtained for all participants. Available blood and sputum cultures were analysed. A total of 165 elderly persons (mean age, 82+/-6.8 years) were hospitalised with a lower respiratory tract infection. Familial flu-like illness (OR, 4.25; 95%CI, 1.4-13), better functionality (OR, 4; 95%CI, 1.3-14.15), and leucocyte count <10(10)/l (OR, 3; 95%CI, 1.3-7.1) were predictive for viral lower respiratory tract infection. Sixty (36.5%) definite diagnoses (positive blood culture, viral culture, or serological test) and seven (4.2%) probable diagnoses (positive sputum culture) were obtained. An early diagnosis (within 72 h) was possible in 38 (23%) and a late diagnosis in 29 (17.6%) participants. A nasopharyngeal swab contributed in 60.5% of the cases to an early diagnosis. Viral culture identified half (22/43) of the lower respiratory tract infections caused by influenza but only one of six lower respiratory tract infections caused by respiratory syncytial virus. In conclusion, a history of flu-like illness in family members and a total leucocyte count within normal limits makes a viral cause more likely in elderly people hospitalised with a lower respiratory tract infection during winter. Viral culture and rapid antigen detection are insensitive in elderly patients hospitalised with a lower respiratory tract infection.


Subject(s)
Hospital Mortality/trends , Hospitalization/statistics & numerical data , Pneumonia, Viral/epidemiology , Respiratory Tract Infections/epidemiology , Respiratory Tract Infections/virology , Age Factors , Aged , Aged, 80 and over , Belgium/epidemiology , Cohort Studies , Female , Geriatric Assessment , Humans , Incidence , Logistic Models , Male , Pneumonia, Viral/virology , Probability , Prognosis , Prospective Studies , Risk Assessment , Statistics, Nonparametric , Survival Analysis
15.
Redox Rep ; 5(4): 207-14, 2000.
Article in English | MEDLINE | ID: mdl-10994875

ABSTRACT

Myeloperoxidase induces apoptosis in src- or raxs-transformed fibroblasts, but not in parental nontransformed fibroblasts. This selectivity seems to be based on superoxide anion production by transformed cells, a recently described characteristic feature of transformed cells. Myeloperoxidase-mediated apoptosis induction is inhibited by SOD, catalase, 4-aminobenzoyl hydrazide, taurine and DMSO. This pattern of inhibition allows us to conclude that transformed cell derived superoxide anions dismutate to hydrogen peroxide, which fosters HOCl formation by myeloperoxidase. Hydrogen peroxide formation thereby is the rate-limiting step and depends on the cell density. In a second step, HOCl interacts with superoxide anions to yield the highly reactive apoptosis inducing hydroxyl radical. This conclusion was verified through selective apoptosis induction in transformed cells by direct addition of HOCl, which was also inhibited by SOD and DMSO. Our findings demonstrate a specific interplay between target cell derived superoxide anions and MPO during selective apoptosis induction.


Subject(s)
Apoptosis , Cell Transformation, Neoplastic/metabolism , Peroxidase/physiology , Superoxides/metabolism , Buthionine Sulfoximine/pharmacology , Cells, Cultured , Genes, ras , Humans , Hypochlorous Acid/metabolism , Superoxide Dismutase/pharmacology
16.
Anticancer Res ; 20(4): 2297-306, 2000.
Article in English | MEDLINE | ID: mdl-10953288

ABSTRACT

A novel concept for the control of oncogenesis has been established for fibroblasts. Transformed fibroblasts are subject to intercellular induction of apoptosis by TGF-beta or FGF-triggered nontransformed neighboring cells. If this control system acts in vivo as efficiently as it does in vitro, tumor formation should require the establishment of resistance mechanisms directed against intercellular induction of apoptosis. In line with this hypothesis, ex vivo tumor cells have been recently shown to be resistant to intercellular induction of apoptosis, whereas cells transformed in vitro and not passaged in an organism were regularly sensitive. Based on the knowledge of signaling between transformed and nontransformed cells during intercellular induction of apoptosis, several possible mechanisms for resistance of tumor cells are summarized in this paper.


Subject(s)
Apoptosis , Neoplasms/pathology , Cell Transformation, Neoplastic , Glutathione/physiology , Nitric Oxide/physiology , Precancerous Conditions/pathology , Proto-Oncogene Proteins c-bcl-2/physiology , Superoxide Dismutase/physiology
17.
Anticancer Res ; 20(4): 2361-70, 2000.
Article in English | MEDLINE | ID: mdl-10953297

ABSTRACT

Elimination of transformed fibroblasts through intercellular induction of apoptosis has been postulated as representing an efficient control step during oncogenesis. Whereas fibroblasts transformed by chemical carcinogens in vitro were sensitive to intercellular induction of apoptosis, ex vivo tumour cells derived from animals treated with chemical carcinogens were resistant to this control step. Resistance was achieved through two different mechanisms. Two cell lines overexpressed endogenous survival factors and thus the action of intercellular signalling (ICS) was not sufficient for complete depletion of endogenous survival factors. One of the resistant ex vivo tumour lines contained the same concentration of endogenous survival factors as its in vitro transformed and sensitive counterpart, but the endogenous survival factors were protected from the action of ICS in the resistant tumour cell line. In addition, the ex vivo tumour cell lines showed a marked independence of exogenous survival factors. Our data indicate that tumour formation requires independence of control by neighbouring cells and by exogenous survival factors.


Subject(s)
Apoptosis , Neoplasms/pathology , Animals , Cell Survival , Cell Transformation, Neoplastic , Cycloheximide/pharmacology , Mice , Transforming Growth Factor beta/pharmacology , Tumor Cells, Cultured
18.
Int J Oncol ; 17(1): 97-102, 2000 Jul.
Article in English | MEDLINE | ID: mdl-10853024

ABSTRACT

Serum contains exogenous survival factors for fibroblasts. Removal of these exogenous factors causes inactivation of endogenous survival factors, subsequent release of a constitutively expressed apoptosis machinery from negative control and apoptosis. Inactivation of endogenous survival factors after serum withdrawal is mediated by reactive oxygen species and can be rapidly reversed through re-addition of serum. Oxidative inactivation of endogenous survival factors after depletion of exogenous survival factors as well as the process of reversion to the active state do not require protein synthesis, indicating the existence of a constitutively expressed regulatory system that controls the interaction of exogenous and endogenous survival factors.


Subject(s)
Apoptosis/physiology , Cell Survival/physiology , Reactive Oxygen Species/physiology , Animals , Apoptosis/drug effects , Blood , Cell Line , Cell Line, Transformed , Cell Survival/drug effects , Culture Media , Culture Media, Serum-Free , Cycloheximide/pharmacology , Fibroblasts/cytology , Fibroblasts/drug effects , Kinetics , Mice , Protein Synthesis Inhibitors/pharmacology , Transforming Growth Factor beta/pharmacology
19.
Anticancer Res ; 19(1A): 87-103, 1999.
Article in English | MEDLINE | ID: mdl-10226529

ABSTRACT

Fibroblasts constitutively express a functional apoptosis machinery which is under negative control by operationally defined endogenous survival factors. Oncogenic transformation causes a marked downmodulation of endogenous survival factor concentration which renders transformed cells more sensitive to various apoptosis stimuli compared to their nontransformed counterparts. Endogenous survival factors can be inactivated by reactive oxygen species (ROS). Endogenous survival factors are the ultimate targets for apoptosis-inducing factors derived from TGF-beta-triggered nontransformed cells during intercellular induction of apoptosis. During this control step of oncogenesis, endogenous survival factors in transformed cells are inactivated by ROS and the apoptosis machinery is released from negative control. This mechanism leads to the specific elimination of transformed cells. Our data show that the transformed state causes both the ability of the cells to perceive the apoptosis-inducing signal and a decrease in the concentration of endogenous survival factors. These two mechanisms are of central importance for the regulation of intercellular induction of apoptosis.


Subject(s)
Apoptosis , Cell Transformation, Neoplastic/pathology , Animals , Cell Communication , Cell Survival , Genes, p53/physiology , Humans , Phenotype , Reactive Oxygen Species , Transforming Growth Factor beta/pharmacology
20.
Acta Cardiol ; 53(4): 195-9, 1998.
Article in English | MEDLINE | ID: mdl-9842404

ABSTRACT

Thiamine deficiency can have cardiovascular and neurological manifestations. Cardiac beriberi is classically thought to represent a high-output state with oliguria and lactic acidosis. The condition can, however, also present itself with a low cardiac output and fulminant vascular collapse, or as an acute fatal form, causing sudden death, without clear-cut signs of cardiomegaly. In the western society beriberi is mainly encountered in alcoholics. We report on two cases, one with high-output failure and the other with low-output failure and cardiovascular collapse. In both patients the diagnosis of shoshin syndrome was made, and and both showed a spectacular improvement of congestive heart failure symptoms after treatment with thiamine. A therapeutic trial with thiamine is the only way to rapid diagnosis.


Subject(s)
Beriberi/complications , Heart Diseases/etiology , Adult , Beriberi/diagnosis , Beriberi/drug therapy , Cardiac Output , Heart Diseases/diagnosis , Heart Diseases/drug therapy , Heart Diseases/physiopathology , Hemodynamics , Humans , Male , Middle Aged , Syndrome , Thiamine/therapeutic use
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