Showing papers in "Apmis in 2013"
TL;DR: Evidence is presented to support a view that the biofilm lifestyle dominates chronic bacterial infections, where bacterial aggregation is the default mode, and that subsequent biofilm development progresses by adaptation to nutritional and environmental conditions.
Abstract: Acute infections caused by pathogenic bacteria have been studied extensively for well over 100 years. These infections killed millions of people in previous centuries, but they have been combated effectively by the development of modern vaccines, antibiotics and infection control measures. Most research into bacterial pathogenesis has focused on acute infections, but these diseases have now been supplemented by a new category of chronic infections caused by bacteria growing in slime-enclosed aggregates known as biofilms. Biofilm infections, such as pneumonia in cystic fibrosis patients, chronic wounds, chronic otitis media and implant- and catheter-associated infections, affect millions of people in the developed world each year and many deaths occur as a consequence. In general, bacteria have two life forms during growth and proliferation. In one form, the bacteria exist as single, independent cells (planktonic) whereas in the other form, bacteria are organized into sessile aggregates. The latter form is commonly referred to as the biofilm growth phenotype. Acute infections are assumed to involve planktonic bacteria, which are generally treatable with antibiotics, although successful treatment depends on accurate and fast diagnosis. However, in cases where the bacteria succeed in forming a biofilm within the human host, the infection often turns out to be untreatable and will develop into a chronic state. The important hallmarks of chronic biofilm-based infections are extreme resistance to antibiotics and many other conventional antimicrobial agents, and an extreme capacity for evading the host defences. In this thesis, I will assemble the current knowledge on biofilms with an emphasis on chronic infections, guidelines for diagnosis and treatment of these infections, before relating this to my previous research into the area of biofilms. I will present evidence to support a view that the biofilm lifestyle dominates chronic bacterial infections, where bacterial aggregation is the default mode, and that subsequent biofilm development progresses by adaptation to nutritional and environmental conditions. I will make a series of correlations to highlight the most important aspects of biofilms from my perspective, and to determine what can be deduced from the past decades of biofilm research. I will try to bridge in vitro and in vivo research and propose methods for studying biofilms based on this knowledge. I will compare how bacterial biofilms exist in stable ecological habitats and opportunistically in unstable ecological habitats, such as infections. Bacteria have a similar lifestyle (the biofilm) in both habitats, but the fight for survival and supremacy is different. On the basis of this comparison, I will hypothesize how chronic biofilm infections are initiated and how bacteria live together in these infections. Finally, I will discuss different aspects of biofilm infection diagnosis. Hopefully, this survey of current knowledge and my proposed guidelines will provide the basis and inspiration for more research, improved diagnostics, and treatments for well-known biofilm infections and any that may be identified in the future.
816 citations
TL;DR: A critical reappraisal of JCPyV infection, replication and disease seems warranted given the increasing number of immunologically vulnerable patients.
Abstract: JC polyomavirus (JCPyV) was the first of now 12 PyVs detected in humans, when in 1964, PyV particles were revealed by electron microscopy in progressive multifocal leukoencephalopathy (PML) tissues. JCPyV infection is common in 35-70% of the general population, and the virus thereafter persists in the renourinary tract. One third of healthy adults asymptomatically shed JCPyV at approximately 50,000 copies/mL urine. PML is rare having an incidence of <0.3 per 100,000 person years in the general population. This increased to 2.4 per 1000 person years in HIV-AIDS patients without combination antiretroviral therapy (cART). Recently, PML emerged in multiple sclerosis patients treated with natalizumab to 2.13 cases per 1000 patients. Natalizumab blocks α4-integrin-dependent lymphocyte homing to the brain suggesting that not the overall cellular immunodeficiency but local failure of brain immune surveillance is a pivotal factor for PML. Recovering JCPyV-specific immune control, e.g., by starting cART or discontinuing natalizumab, significantly improves PML survival, but is challenged by the immune reconstitution inflammatory syndrome. Important steps of PML pathogenesis are undefined, and antiviral therapies are lacking. New clues might come from molecular and functional profiling of JCPyV and PML pathology and comparison with other replicative pathologies such as granule cell neuronopathy and (meningo-)encephalitis, and non-replicative JCPyV pathology possibly contributing to some malignancies. Given the increasing number of immunologically vulnerable patients, a critical reappraisal of JCPyV infection, replication and disease seems warranted.
146 citations
TL;DR: In this paper, a review summarizes epidemiological evidence and current immunological knowledge concerning the hygiene hypothesis concerning the development of both autoimmune and allergic diseases, and concludes that environmental factors have greatly contributed to the increasing prevalence of immune-mediated disorders.
Abstract: Autoimmune and allergic diseases have become a major health problem in the Western world during past decades. The hygiene hypothesis suggests that decreased microbial exposure in childhood leads to increasing prevalence of these diseases. This review summarizes epidemiological evidence and current immunological knowledge concerning the hygiene hypothesis. Recent results from Russian Karelia and Finland imply that environmental factors have greatly contributed to the increasing prevalence of immune-mediated disorders. Infections, or lack of them, may indeed be strongly involved in the development of both autoimmune and allergic diseases.
108 citations
TL;DR: Although BKPyV has been associated with cancer development, especially in the bladder, definitive evidence of a role in human malignancy is lacking and the current treatment strategy for PyVAN is to allow reconstitution of immune function by reducing or changing the immunosuppressive medication.
Abstract: Polyomavirus BK (BKPyV) infects most people subclinically during childhood and establishes a lifelong infection in the renourinary tract. In most immunocompetent individuals, the infection is completely asymptomatic, despite frequent episodes of viral reactivation with shedding into the urine. In immunocompromised patients, reactivation followed by high-level viral replication can lead to severe disease: 1-10% of kidney transplant patients develop polyomavirus-associated nephropathy (PyVAN) and 5-15% of allogenic hematopoietic stem cell transplant patients develop polyomavirus-associated haemorrhagic cystitis (PyVHC). Other conditions such as ureteric stenosis, encephalitis, meningoencephalitis, pneumonia and vasculopathy have also been associated with BKPyV infection in immunocompromised individuals. Although BKPyV has been associated with cancer development, especially in the bladder, definitive evidence of a role in human malignancy is lacking. Diagnosis of PyVAN and PyVHC is mainly achieved by quantitative PCR of urine and plasma, but also by cytology, immunohistology and electron microscopy. Despite more than 40 years of research on BKPyV, there is still no effective antiviral therapy. The current treatment strategy for PyVAN is to allow reconstitution of immune function by reducing or changing the immunosuppressive medication. For PyVHC, treatment is purely supportive. Here, we present a summary of the accrued knowledge regarding BKPyV.
87 citations
TL;DR: Electron microscopy, immunohistochemistry, and viral load measurements indicate an etiological role of active TSPyV infection in the development of trichodysplasia spinulosa, a skin disease of severely immunocompromised hosts characterized by follicular distention and keratotic spine formation especially on the face.
Abstract: Trichodysplasia spinulosa-associated polyomavirus (TSPyV) is a new species of the family Polyomaviridae that was discovered in 2010. TSPyV infects humans and is associated with the development of a rare disease called trichodysplasia spinulosa. Trichodysplasia spinulosa is a skin disease of severely immunocompromised hosts characterized by follicular distention and keratotic spine formation especially on the face. Electron microscopy, immunohistochemistry, and viral load measurements indicate an etiological role of active TSPyV infection in the development of this disease. This review will address virological and pathogenic properties of TSPyV, as well as epidemiologic, diagnostic, and therapeutic aspects of TSPyV infection.
79 citations
TL;DR: The data indicate that loss of SPop expression was common in GC, CRC and PCA, but somatic mutation of SPOP in this study was rare in these tumors, and provides a possibility that Loss of expression of SP Op gene might play a role in cancer pathogenesis by altering TSG functions of SP OP.
Abstract: Mounting evidence exists that alterations of ubiquitination processes are involved in cancer pathogenesis. Speckle-type POZ protein (SPOP) is a key adaptor for Cul3-based ubiquitination process. Recent studies reported that SPOP may be a tumor suppressor gene (TSG) and somatic mutation of SPOP was detected in prostate cancer (PCA). The aim of this study was to see whether alterations of SPOP protein expression and somatic mutation of SPOP gene are features of cancers. In this study, we analyzed SPOP somatic mutation in 45 gastric (GC), 45 colorectal cancer (CRC) and 45 PCA by single-strand conformation polymorphism (SSCP). Also, we analyzed SPOP protein expression in 60 GC, 60 CRC and 60 PCA by immunohistochemistry. Overall, we detected three somatic missense mutations of SPOP gene in the coding sequences (p.Ser14Leu, p.Tyr87Cys and p.Phe133Leu). The mutations were observed in two PCA and one CRC. Of note, the p.Phe133Leu was a recurrent mutation reported in an earlier study. In the immunohistochemistry, SPOP protein was expressed in normal gastric, colonic and prostate epithelial cells, whereas it was lost in 30% of GC, 20% of CRC and 37% of PCA. Our data indicate that loss of SPOP expression was common in GC, CRC and PCA, but somatic mutation of SPOP in this study was rare in these tumors. Also, the data provide a possibility that loss of expression of SPOP gene might play a role in cancer pathogenesis by altering TSG functions of SPOP.
74 citations
TL;DR: Vanillin, 4‐hydroxybenzoic, and gallic acids at concentrations within the range of 40 to 400 μg/mL increased the production of N–3‐oxo‐dodecanoyl‐homoserine lactone in P. aeruginosa PAO1 which suggests a possible relationship between stimulation of biofilm formation and Las Quorum Sensing system of this bacterium.
Abstract: In the natural environment, bacteria predominantly exist in matrix-enclosed multicellular communities associated with various surfaces, referred to as biofilms. Bacteria in biofilms are extremely resistant to antibacterial agents thus causing serious problems for antimicrobial therapy. In this study, we showed that different plant phenolic compounds, at concentrations that did not or weakly suppressed bacterial growth, increased the capacity of Pseudomonas aeruginosa PAO1 to form biofilms. Biofilm formation of P. aeruginosa PAO1 was enhanced 3- to 7-fold under the action of vanillin and epicatechin, and 2- to 2.5-fold in the presence of 4-hydroxybenzoic, gallic, cinnamic, sinapic, ferulic, and chlorogenic acids. At higher concentrations, these compounds displayed an inhibiting effect. Similar experiments carried out for comparison with Agrobacterium tumefaciens C58 showed the same pattern. Vanillin, 4-hydroxybenzoic, and gallic acids at concentrations within the range of 40 to 400 μg/mL increased the production of N-3-oxo-dodecanoyl-homoserine lactone in P. aeruginosa PAO1 which suggests a possible relationship between stimulation of biofilm formation and Las Quorum Sensing system of this bacterium. Using biosensors to detect N-acyl-homoserine lactones (AHL), we demonstrated that the plant phenolics studied did not mimic AHLs.
73 citations
TL;DR: This review article tries to unleash some of the mysteries related to the formation of MN inside the cancer cell, and discusses the possible effects and the events post MN formation in the cancer cells.
Abstract: Micronucleus (MN) is the small nucleus that forms whenever a chromosome or its fragment is not incorporated into one of the daughter nuclei during cell division. Any form of genotoxic stress due to extraneous or internal factors leads to formation of a MN, which serves as an indicator of chromosomal instability. Chromosomal damage and formation of MN are believed to play a significant role in the pathogenesis of many malignancies. Studies have shown that MN assay can be used as a tool for risk prediction, screening, diagnosis, prognosis and as a treatment-response indicator in cancers. With the advancements in technology, greater details are becoming available regarding the molecular events in carcinogenesis. The micronuclei (MNi) in the cancer cells are now being used as tools to understand the pathogenetics of the malignancies. However, despite large number of studies on MNi in lymphocytes or exfoliated cells of cancer patients, the data regarding a cancer cell MN remain scarce. This review article tries to unleash some of the mysteries related to the formation of MN inside the cancer cell. Also, it discusses the possible effects and the events post MN formation in the cancer cell.
67 citations
TL;DR: The etiologic role of MCPyV in MCC opens up opportunities to improve the understanding of this cancer and to potentially improve its treatment.
Abstract: The Merkel cell polyomavirus (MCPyV), identified in humans in 2008, is associated with a relatively rare but aggressive neuroendocrine skin cancer, the Merkel cell carcinoma (MCC). MCC incidence is increasing due to the advancing age of the population, the increase in damaging sun exposure and in the number of immunocompromised individuals. MCPyV must be considered as the etiological agent of MCC and thus is the first example of a human oncogenic polyomavirus. MCPyV infection is common, and seroprevalence studies indicate that widespread exposure begins early in life. The majority of adults have anti-MCPyV antibodies and there is a growing body of evidence that healthy human skin harbors resident or transient MCPyV suggesting that MCPyV infection persists throughout life. However, the mode of transmission, the host cells, and the latency characteristics of this virus remain to be elucidated. In addition, it is still not clear whether MCPyV is associated with diseases or lesions other than Merkel cell carcinoma. The etiologic role of MCPyV in MCC opens up opportunities to improve the understanding of this cancer and to potentially improve its treatment.
65 citations
TL;DR: The methanogenic archaea load correlating with periodontitis severity further supports the pathogenic role of metanobrevibacter oralis, a periodontal pathogen, and detection and quantification of M. oralis inperiodontal pockets could help the laboratory diagnosis and follow‐up ofperiodontitis.
Abstract: Archaea are non-bacterial prokaryotes associated with oral microbiota in humans, but their roles in oral pathologies remain controversial. Several studies reported the molecular detection of methanogenic archaea from periodontitis, but the significance of this association has not been confirmed yet. An electronic search was therefore conducted in MEDLINE-Pubmed to identify all papers published in English connecting archaea and periodontal infections. Data analysis of the selected studies showed that five genera of methanogenic archaea have been detected in the subgingival microbiota, Methanobrevibacter oralis being the most frequently detected species in 41% of periodontitis patients and 55% of periodontal pockets compared to 6% of healthy subjects and 5% of periodontally-healthy sites (p < 10(-5) , Chi-squared test). Based on the five determination-criteria proposed by Socransky (association with disease, elimination of the organism, host response, animal pathogenicity and mechanisms of pathogenicity), M. oralis is a periodontal pathogen. The methanogenic archaea load correlating with periodontitis severity further supports the pathogenic role of methanogenic archaea in periodontitis. Therefore, detection and quantification of M. oralis in periodontal pockets could help the laboratory diagnosis and follow-up of periodontitis. Determining the origin, diversity and pathogenesis of archaea in periodontal infections warrants further investigations.
62 citations
TL;DR: It was concluded in the study that nucleolin was overexpressed in GCs and was an independent prognostic marker for better survival while high cytoplasmic staining was closely associated with worse prognosis for GC patients.
Abstract: The aim of this study was to investigate the expression of nucleolin in tumorous tissues and corresponding non-malignant tissues in gastric cancer (GC), and the correlation of different expression sites with clinicopathologic parameters and prognosis. Immunohistochemistry was used for detecting the expression levels of nucleolin in GC tissues and corresponding non-malignant tissues from 124 gastrectomy specimens with stage I-III. Staining results were correlated with clinicopathologic features and survival. Both GC tissues and corresponding non-malignant tissues showed nucleolar staining for nucleolin. Nucleolin expression was higher in GC tissues than in non-malignant tissues. Among the 124 GCs, 85 (68.5%) were nucleolin-high. No significant correlation between nucleolin expression and other clinicopathologic parameters was found. The Cox univariate analysis indicated that both cytoplasmic staining and nucleolar staining of nucleolin expression correlated with patients' prognosis (log-rank, p < 0.0001; p = 0.0075, respectively). It was concluded in the study that nucleolin was overexpressed in GCs. A high level of nucleolar expression of nucleolin was an independent prognostic marker for better survival while high cytoplasmic staining was closely associated with worse prognosis for GC patients.
TL;DR: The performance in CTC enumeration was compared between the ImageStream and CellSearch systems, which combines the strengths of flow cytometry and fluorescent microscope in a single platform.
Abstract: Circulating tumor cell (CTC) enumeration is important clinically for identifying prognostic and predictive factors in patients with solid cancers. The CellSearch device (Veridex) is an immunomagnetic CTC selection and enumeration system used in clinical practice. The ImageStream (Amnis) combines the strengths of flow cytometry and fluorescent microscopy in a single platform and has potential application for CTC counting. The performance in CTC enumeration was compared between the ImageStream and CellSearch systems.
Various numbers of PANC-1 tumor cells were spiked into 7.5 mL of peripheral blood from a healthy donor. Before cell analysis by the ImageStream, tumor cell enrichment was performed by immunomagnetic selection with anti-EpPCAM. Anti-CD45 and anti-CK markers were used to discriminate between tumor cells and leukocytes. The ratios of tumor cells recovered from each dilution were calculated for both methods. The Wilcoxon rank test was applied to compare the results of the two methods and the reference value.
The results of the two tested methods differed significantly from the reference value, but did not differ between them. Nevertheless, lower level of trueness and precision was observed in ImageStream when fewer numbers of CTCs were analyzed.
Our results suggest that ImageStream platform for CTC enumeration has a potential value for the early diagnosis of disseminated disease, but needs an improvement of precision for the enumeration of low number of CTC.
TL;DR: Standardized quantitative real‐time PCR methods, definition of a clear clinical cutoff value, timing in the collection of respiratory samples, are also crucial to understand the pathogenic role, if any, of KIPyV and WUPyV in human pathology.
Abstract: In 2007, two novel polyomaviruses KI and WU were uncovered in the respiratory secretions of children with acute respiratory symptoms Seroepidemiological studies showed that infection by these viruses is widespread in the human population Following these findings, different biological specimens and body compartments have been screened by real-time PCR in the attempt to establish a pathogenetic role for KI polyomavirus (KIPyV) and WU polyomavirus (WUPyV) in human diseases Although both viruses have been found mainly in respiratory tract samples of immunocompromised patients, a clear causative link with the respiratory disease has not been established Indeed, the lack of specific clinical or radiological findings, the frequent co-detection with other respiratory pathogens, the detection in subjects without signs or symptoms of respiratory disease, and the variability of the viral loads measured did not allow drawing a definitive conclusion Prospective studies carried out on a large sample size including both immunocompromised and immunocompetent patients with and without respiratory symptoms are needed Standardized quantitative real-time PCR methods, definition of a clear clinical cutoff value, timing in the collection of respiratory samples, are also crucial to understand the pathogenic role, if any, of KIPyV and WUPyV in human pathology
TL;DR: The data indicate that DNMT3A gene is mutated mainly in AML, but it occurs in other cancers, such as ALL and lung cancer, despite the lower incidences, and suggest that DN MT3A is altered in many cancer types by various ways, including somatic mutations, allelic loss and loss of expression that might play roles in tumorigenesis.
Abstract: DNMT3A, a DNA methyltransferase that functions for de novo methylation, is important in development and many cellular processes related to tumorigenesis. Somatic mutations of DNMT3A gene, including recurrent mutations in its Arg-882, were recently reported in acute myelogenous leukemia (AML), strongly suggesting its role in development of AML. To see whether DNMT3A mutation occurs in other malignancies as well, we analyzed DNMT3A in 916 cancer tissues from 401 hematologic malignancies (AML, acute lymphoblastic leukemias (ALL), multiple myelomas and lymphomas) and 515 carcinomas (lung, breast, prostate, colorectal and gastric carcinomas) using a single-strand conformation polymorphism (SSCP) assay. We identified DNMT3A mutations, especially the Arg-882 mutations, in adulthood AML (9.4%). In addition, we found DNMT3A mutations in pre-B-ALL and three lung cancers at lower frequencies. Allelic loss of DNMT3A was frequently observed in most cancer types analyzed, including lymphomas (48.1%), gastric cancers (23.5%) and lung cancers (18.3%) irrespective of DNMT3A mutation. Also, loss of DNMT3A expression was common in lung cancers (46.4%), and was associated with the allelic loss. Our data indicate that DNMT3A gene is mutated mainly in AML, but it occurs in other cancers, such as ALL and lung cancer, despite the lower incidences. Also, the data suggest that DNMT3A is altered in many cancer types by various ways, including somatic mutations, allelic loss and loss of expression that might play roles in tumorigenesis.
TL;DR: The characterization of a carbapenemase-producing K. pneumoniae strain isolated from the urine sample recovered from an elderly male non-hospitalized patient in Taza (northern Morocco), which was resistant to aminoglycosides, fluoroquinolones, sulfonamides and tetracycline but remained susceptible to fosfomycin and colistin.
Abstract: To the Editor The emergence and dissemination of carbapenem-resistant Enterobacteriaceae represent a significant threat to the management of nosocomial and community-acquired infections (1). Carbapenem-hydrolysing b-lactamases are represented by three molecular classes of b-lactamases: A, B, and D. The best-known carbapenemases are KPC-type (Ambler class A), IMP and VIM types (class B), and OXA48 (class D), mostly identified in Klebsiella pneumoniae as a source of nosocomial outbreaks (2). Recently, a novel metallo-b-lactamase (MBL) named NDM-1 (New Delhi metallo-b-lactamase) has been identified from a K. pneumoniae strain recovered in Sweden from a patient previously hospitalized in India (3). Very recently, NDM-1 producers have been reported in the environment and in communityacquired infections (1, 3). In this study, we report the characterization of a carbapenemase-producing K. pneumoniae strain (Kpp474) isolated from the urine sample recovered from an elderly male (49 years) non-hospitalized patient in Taza (northern Morocco). He had previously received broadspectrum cephalosporins and fluoroquinolones for recurrent urinary tract infections; the treatment was changed to amikacin and the patient recovered. Antibiotic susceptibilities and minimal inhibitory concentrations were determined by disc diffusion and agar dilution methods respectively, in accordance with the recommendations of the Antibiogram Committee of the French Society of Microbiology (http://www.sfm-microbiologie.org). Isolate Kpp474 was resistant to amoxicillin (>256 mg/ L), amoxicillin clavulanate combination (>16/ 8 mg/L), ertapenem (16 mg/L), cefotaxime (>256 mg/L), ceftriaxone (>256 mg/L), cefepime (64 mg/L), ceftazidime (>256 mg/L), aztreonam (64 mg/L) and cefoxitin (>256 mg/L), and had an intermediate susceptibility to imipenem (6 mg/L). In addition, the isolate was also resistant to aminoglycosides (except to amikacin), fluoroquinolones, sulfonamides and tetracycline, but remained susceptible to fosfomycin and colistin. This isolate was positive for modified Hodge test and double-disc synergy test (4, 5), in which only aztreonam showed a positive synergy with clavulanate. We used the previously described PCRs (2, 6) followed by sequencing, to screen and characterize the carbapenem-hydrolysing b-lactamase genes (blaVIM, blaIMP, blaKPC, blaGES, blaNDM and blaOXA-48). In addition, the carriage of plasmid-encoded blaCTX-M, blaTEM, blaOXA-1, blaSHV and blaAmpC b-lactamase genes, the aac(6′)-Ib, aac(3)-II aminoglycoside resistance genes, the quinolone resistance genes qnrA, B, S, the tetracycline resistance genes tetA, and class 1 integron were investigated (7–9). The isolate was positive for blaNDM-1, blaVIM-1 and blaOXA-48. The search for narrow-spectrum b-lactamases, extended spectrum b-lactamase (ESBL) and AmpC genes revealed that Kp474 isolate harboured the narrowspectrum b-lactamase genes blaTEM-1, blaSHV-1 and blaOXA-1, together with the ESBL gene blaCTX-M. However, they did not harbour AmpC-encoding genes. In addition, the plasmid-encoded quinolone resistance genes qnrB and aac(6′)-Ib-cr, aminoglycoside resistance gene aac(3)-II and tetracycline resistance gene tetA were present in the Kp474 isolate. A class 1 integron was detected, with an amplicon of 1.6 kb in length. Plasmid analysis, performed using the alkaline lysis and S1 nuclease-PFGE method (10, 11), revealed that K. pneumoniae Kpp474 harboured five plasmids of ca. 250,130, 60, 52 and 7 kb. The transfer of the b-lactams resistance markers from Kpp 474 to Escherichia coli K12J5 (azide resistant) was performed by mating assays, with selection based on different antibiotics (ertapenem 0.25 mg/L, kanamycin 2 mg/L and ceftazidime 1 mg/L) (12). Two E. coli K12J5 transconjugant isolates (Tc1 and Tc2) were detected with different phenotypes. The Tc1 transconjugant showed an MBL and an ESBL phenotype (4, 5) and was resistant to nalidixic acid, amoxicillin (>256 mg/L), clavulanic acid/amoxicillin (>16/8 mg/L), ceftazidime
TL;DR: Multivariate survival analysis demonstrated that high levels of uPAR(I) were significantly associated with short overall survival (OS) in SCLC patient, independent of LDH and PS.
Abstract: The prognosis of small cell lung cancer (SCLC) remains poor with a 5-year survival rate of 4-6%. In non-small cell lung cancer (NSCLC), high levels of intact and cleaved forms of the receptor for urokinase plasminogen activator (uPAR) are significantly associated with short overall survival. Our aim was therefore to determine the prognostic value of the different uPAR forms in blood from SCLC patients. Serum samples from 92 treatment naive SCLC patients were analysed. Intact uPAR, uPAR(I-III), intact and cleaved uPAR, uPAR(I-III) + uPAR(II-III) and the liberated domain I, uPAR(I) were measured using time-resolved fluorescence immunoassays (TR-FIA 1-3). Assessment of association of the uPAR forms to overall survival (OS) was done using Cox regression analysis adjusted for clinical covariates [age, gender, stage, lactate dehydrogenase (LDH), WHO performance status (PS)]. Multivariate survival analysis demonstrated that high levels of uPAR(I) were significantly (p = 0.009) associated with short overall survival (OS). Patients with uPAR(I) levels above the second tertile had a hazard ratio (HR) of 1.9 (95% confidence interval (CI): 1.1-3.3), compared to patients with levels below the first tertile. High serum uPAR(I) levels are associated with short OS in SCLC patient, independent of LDH and PS.
TL;DR: Serological studies using capsomer‐based or virus‐like particle (VLP)‐based enzyme‐linked immunosorbent assay (ELISA) revealed that HPyV6, 7, 9 and 12 are circulating in the human population.
Abstract: Since the discovery of Merkel cell polyomavirus and its causative association with Merkel cell carcinoma (MCC), six human polyomaviruses (HPyVs) have been identified that, so far, lack any disease association, which include the human polyomaviruses (HPyV) 6, 7, 9, 10 and 12 as well as the Saint Louis polyomavirus (STLPyV). PCR studies revealed that HPyV6 and HPyV7 are shed from the skin of healthy subjects and of patients suffering from various skin tumours. HPyV6, 7 and 9 were sporadically detected in body fluids and excretions of immunocompromised patients and healthy subjects. HPyV10 was identified in papillomavirus-induced anal condylomas, and variants of HPyV10, named MWPyV and MX polyomavirus (human) (MXPyV), as well as STLPyV were detected in faeces of diarrheal and healthy children. HPyV12 was discovered in organs of the digestive tract of patients suffering from various malignant diseases. Serological studies using capsomer-based or virus-like particle (VLP)-based enzyme-linked immunosorbent assay (ELISA) revealed that HPyV6, 7, 9 and 12 are circulating in the human population. As all other HPyVs, the novel polyomaviruses encode small and large T antigens and thus are potentially oncogenic. However, several studies have revealed a lack of association of HPyV6, 7 and 9 with numerous human tumours. In the future, it will be important to unravel the cell types and body compartments of the novel HPyVs′ reservoir and to search for possible associations with cancer and non-malignant diseases.
TL;DR: Matrix‐assisted laser desorption/ionization time of flight mass spectrometry (MALDI‐TOF MS) was in this study found to be a powerful tool in fast diagnosis of Gram‐negative bacteria and fungi and to a lesser degree of Gram positives.
Abstract: Matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF MS) is a promising and fast method for identifying fungi and bacteria directly from positive blood cultures. Various pre-treatment methods for MALDI-TOF MS identification have been reported for this purpose. In-house results for identification of bacterial colonies by MALDI-TOF MS using a cut-off score of 1.5 did not reduce the diagnostic accuracy compared with the recommended cut-off score of 1.8. A 3-month consecutive study of positive blood cultures was carried out in our laboratory to evaluate whether the Sepsityper™ Kit (Bruker Daltonics) with Biotyper 2.0 software could be used as a fast diagnostic tool for bacteria and fungi and whether a 1.5 cut-off score could improve species identification compared with the recommended score of 1.8. Two hundred and fifty-six positive blood vials from 210 patients and 19 blood vials spiked with fungi were examined. Using the cut-off score of 1.8, 81% Gram-negative bacteria were identified to the species level compared to 84% using a cut-off score of 1.5. For Gram-positive bacteria 44% were identified to the species level with a cut-off of 1.8 compared to 55% with the value of 1.5. The overall identification rate was 63% (cut-off 1.5) and 54% (cut-off 1.8). Seventy-seven per cent of fungal species were identified with both log scores. MALDI-TOF MS was in this study found to be a powerful tool in fast diagnosis of Gram-negative bacteria and fungi and to a lesser degree of Gram positives. Using 1.5 as cut-off score increased the diagnosis for both Gram-positives and -negatives bacteria.
TL;DR: Although regarded as a harmless commensal of the skin, P. acnes strongly activates the inflammasome of human peripheral neutrophils, leading to a pro‐inflammatory response.
Abstract: Propionibacterium acnes is a Gram-positive, slow-growing, anaerobic bacillus, predominantly found as a commensal on the skin and mucous membranes of adults. It is, however, also considered an oppor ...
TL;DR: The human gut Planctomycetes content was explored using PCR primers designed to amplify a 240–bp 16S rRNA gene fragment in human stool specimens from individuals in France and in Senegal and from endocarditis patients receiving antibiotics in France.
Abstract: Until now, Planctomycetes bacteria were considered as environmental organisms. Nevertheless, some studies detected Planctomycetes DNA from human gut. We therefore explored the human gut Planctomycetes content. Planctomycetes-specific PCR primers were designed to amplify a 240-bp 16S rRNA gene fragment in human stool specimens from individuals in France and in Senegal and from endocarditis patients receiving antibiotics in France. PCR products were then cloned and sequenced. PCR detection revealed a significantly higher prevalence (1.8% vs 0.4%, p = 0.05) and higher diversity (62 vs 6 phylotypes, p = 0.02) of Planctomycetes 16S rRNA gene in stool specimens collected in Senegal than in France. Also, stool specimens from endocarditis patients exhibited non-significantly higher prevalence (0.6% vs 0.4%) and the ratio of phylotypes by positive patient (3 vs 1.5) than those collected from untreated French individuals. Gemmata sp. related sequences were found in 6/12 individuals. Planctomycetes organisms are a part of the human digestive tract microbiota. Their diversity varied by environment including the geographical origin of the individual and antibiotics treatment.
TL;DR: The results suggest that bacterial DNA as well as deoxynucleotides having stable secondary structures (i.e. hairpins or G‐quadruplex structures) may serve as endogenous, invasion‐inducing TLR9‐ligands and promote local progression and metastasis of cancers in the alimentary tract.
Abstract: Toll-like receptor 9 (TLR9) recognizes both bacterial and self-DNA and it is abundantly expressed in the gastrointestinal tract. In this study, we investigated the influences of both bacterial DNA and specific short DNA sequences on TLR9-mediated gastrointestinal cancer cell invasion. We assessed the effect of various DNA ligands on cellular invasion and on TLR9 and matrix metalloproteinase expression of three gastrointestinal cancer cell lines. DNA-ligands described in this study include CpG-ODN M362, 9-mer (hairpin), human telomeric sequence h-Tel22 G-quadruplex, and bacterial DNAs from Escherichia coli and Helicobacter pylori. All of the DNAs studied were demonstrated to induce invasion in the studied cells. The DNA-induced invasion was inhibited with a broad-spectrum MMP inhibitor and partly also with chloroquine suggesting that it could be mediated via MMP activation, endosomal signaling, and TLR9. Interestingly, H. pylori DNA was shown to induce a more pronounced invasion in a gastric cancer cell line than in the other cell lines. Our results suggest that bacterial DNA as well as deoxynucleotides having stable secondary structures (i.e. hairpins or G-quadruplex structures) may serve as endogenous, invasion-inducing TLR9-ligands and promote local progression and metastasis of cancers in the alimentary tract.
TL;DR: It is demonstrated for the first time thatPLCE1 overexpression correlates with lymph node metastasis and advanced TNM stages of Kazakh ESCC, implicating a role of PLCE1 in cancer metastasis, aggressiveness and aggressiveness in ethnic Kazakh patients with ESCC.
Abstract: Three recent large-scale genome-wide association studies (GWAS) in Chinese Han populations have identified an esophageal squamous cell carcinoma (ESCC) susceptibility locus within phospholipase C epsilon 1 (PLCE1) gene, which encodes a phospholipase involved in intracellular signaling. The expressed PLCE1 in ESCC, however, are inconsistent. This study examined PLCE1 expression by immunohistochemistry (IHC) from 110 ethnic Kazakh ESCC patients and 50 from adjacent normal esophageal tissues (NETs). The expressed PLCE1 was localized in cytoplasm, especially in the peripheral layers of cancer cell nests, which was significantly higher in tumors than in NETs (p < 0.001). Increased expression of PLCE1 was correlated with advanced tumor-node-metastasis (TNM) stages (p = 0.015) and lymph node metastasis (p = 0.003) in patients with ESCC. Of the 110 patients, we examined 50 paired ESCC tissues and corresponding NETs by quantitative RT-PCR (polymerase chain reaction) and the mean mRNA level of PLCE1 in ESCC was 1.85-fold higher compared with those in corresponding NETs (p = 0.0012). Meanwhile, 4 of 5 ESCC cell lines also showed elevated expression of PLCE1 mRNA. Furthermore, elevated expression of PLCE1 mRNA in Kazakh ESCC was associated with its immunoreactivity (ρ = 0.297, p = 0.040), lymph node metastasis (p < 0.001), and advanced TNM stages of ESCC (p = 0.013). To our knowledge, this study demonstrates for the first time that PLCE1 overexpression correlates with lymph node metastasis and advanced TNM stages of Kazakh ESCC, implicating a role of PLCE1 in cancer metastasis and aggressiveness in ethnic Kazakh patients with ESCC. Furthermore, the current findings may warrant investigations into whether inhibiting PLCE1 could be a strategy for targeted anticancer therapy particularly for Kazakh ESCC.
TL;DR: The results demonstrate that, in addition to its contribution to insulin resistance, TLR4 might also play a role in β‐cell dysfunction in type 2 diabetes.
Abstract: Toll-like receptor 4 (TLR4) has received much attention in the recent years due to its role in development of insulin resistance in type 2 diabetes mellitus. Its expression is elevated in fat and muscle from insulin-resistant mice. Several cells of the pancreatic islets, including β-cells and resident macrophages, express TLR4. Our hypothesis is that expression of TLR4 and downstream signalling molecules in islets increases during progression of type 2 diabetes, thereby contributing to β-cell damage. We investigated the hypothesis in the db/db mouse. Islets from male db/db (4, 8 and 15 weeks old) and control db/+ (4 and 15 weeks old) mice were examined for mRNA expression of TLR4 and selected cytokines using qPCR. In addition, cytokine secretion from islets was quantified. TLR4 is expressed in islets from lean and obese mice, displaying a 7.4-fold higher level in 15 weeks old db/db relative to age-matched control (p < 0.01). During progression of clinical type 2 diabetes manifested by hyperglycaemia, TLR4 expression increases 5.6-fold in islets from 15 weeks compared with 4 weeks old db/db mice (p < 0.01). Furthermore, both protein and mRNA levels of all cytokines examined increased. In particular, expression of IL-6 increased with 37 fold. Expression of TLR4 in db/db mouse islets increased in parallel with hyperglycaemia. A similar increase in expression and secretion of TNFα, IL-1 and IL-6 was observed. Our results demonstrate that, in addition to its contribution to insulin resistance, TLR4 might also play a role in β-cell dysfunction in type 2 diabetes.
TL;DR: First report on antimicrobial activity of Finnish monofloral honeys against streptococcal and staphylococcal bacteria is reported, and to the authors' knowledge this is also the first report on the antimicrobial effect of honey against S. pneumoniae.
Abstract: The antimicrobial activity and phenolic compounds of five Finnish honey products against important human pathogens Streptococcus pneumoniae, S. pyogenes, Staphylococcus aureus, and methicillin-resistant S. aureus were analyzed. Microbroth dilution method and HPLC-DAD were used in antimicrobial testing and phenolic compound determination, respectively. Significant antimicrobial activity (p < 0.01) against all the tested pathogens was found from willow herb (Epilobium angustifolium), heather (Calluna vulgaris), and buckwheat (Fagopyrum esculentum) honeys. This is the first report on antimicrobial activity of Finnish monofloral honeys against streptococcal and staphylococcal bacteria. To our knowledge this is also the first report on the antimicrobial effect of honey against S. pneumoniae.
TL;DR: A current evolution in the A. baumannii epidemiology in Marseille is demonstrated with a switch from an epidemic situation to an endemic situation and with several circulating clones.
Abstract: Centre National de Re´fe´rence de la Re´sistance aux Antibiotiques, InstitutPasteur, Paris Cedex, FranceKempf M, Rolain J-M, Azza S, Diene S, Joly-Guillou M-L, Dubourg G, Colson P, Papazian L,Richet H, Fournier P-E, Ribeiro A, Raoult D. Investigation of Acinetobacter baumannii resistanceto carbapenems in Marseille hospitals, south of France: a transition from an epidemic to anendemic situation. APMIS 2012.Carbapenem-resistant Acinetobacter baumannii infections are a worldwide endemic nosocomialthreat. Between December 2010 and April 2011, an increase of carbapenem-resistant A. baumanniiinfections occurred in several Marseille University Hospitals. The aim of this study was to investi-gate the increase of carbapenem-resistant A. baumannii infections and to characterize the mecha-nisms of carbapenem resistance. The increase was detected by a homemade computer surveillanceprogram, known as EPIMIC, that monitors antibiotic resistance profiles on a weekly basis. Duringthis period, positive samples of carbapenem-resistant A. baumannii were retrieved from patients hos-pitalized in different units. Genotyping of the isolates was performed using pulsed-field gel electro-phoresis (PFGE) and multi-locus sequence typing (MLST), and carbapenemase gene analyses wereperformed to detect the presence of carbapenemases and to determine the relationships of theisolates. Carbapenem-resistant A. baumannii were isolated in a total of 11 patients who were hospi-talized in different hospitals units. We identified the presence of the bla
TL;DR: The data show that increased CLic1 protein expression is associated with clinicopathological factors and a poor prognosis of hepatic tumors, and suggest that CLIC1 might represent a valuable prognostic marker for human hepatic tumor.
Abstract: Chloride intracellular channel 1 (CLIC1) is expressed in many human tissues and has been reported to be involved in the regulation of cell cycle, cell proliferation, and differentiation. Its roles in human hepatic tumor, however, remain unclear. The aim of this study was to investigate the clinicopathological significance and expression pattern of CLIC1 in human primary hepatic tumors. We examined the expression pattern of CLIC1 mRNA and protein in hepatic tumors using real-time quantitative RT-PCR and Western blot, respectively. CLIC1 protein and mRNA levels were significantly higher in cancerous tissues compared with corresponding normal tissue. In 85 hepatic tumor tissues, CLIC1 was significantly higher in 69 cases (81.2%), as determined by immunohistochemical staining. Increased CLIC1 expression was correlated with tumor size (p = 0.021), distant metastasis (p = 0.025), pathological TNM (pTNM) stage (p = 0.023), and poor survival (25.11 ± 2.27 vs 45.29 ± 4.28 months, p = 0.001). Our data show that increased CLIC1 protein expression is associated with clinicopathological factors and a poor prognosis of hepatic tumors, and suggest that CLIC1 might represent a valuable prognostic marker for human hepatic tumors.
TL;DR: Liquid‐based preparation in FNA of thyroid nodules shows better‐preserved nuclear details, cleaner background and fewer large papillae than were evident in CS, indicating that LBP reduces the diagnosis of non‐diagnostic or unsatisfactory/atypia of undetermined significance or follicular lesion of und determined significance.
Abstract: Papillary thyroid carcinoma (PTC) is the most common thyroid malignancy. Fine-needle aspiration (FNA) is the most useful tool in the diagnosis of thyroid nodules. Liquid-based preparation (LBP) in FNA of thyroid nodules is now widely used and is replacing the conventional smear (CS). We compared the diagnostic value of the LBP method with that of CS in thyroid lesions. A total of 1767 CS FNA samples and 2523 LBP FNA samples were included in this comparison of diagnostic values. We also assessed the differences in cytomorphologic features in 41 randomly selected cases of PTC. The measured sensitivities of CS and LBP were 78.9% and 76.3%, respectively, and the specificities were 64.2% and 54.9%, respectively, whereas the positive predictive values were 92.3% and 94.3%, respectively, and the negative predictive values were 89.5% and 81.8%, respectively. The cytomorphological features of LBP showed better-preserved nuclear details, cleaner background and fewer large papillae than were evident in CS. The results indicate that LBP reduces the diagnosis of non-diagnostic or unsatisfactory/atypia of undetermined significance or follicular lesion of undetermined significance, although the diagnostic values for CS and LBP are not appreciably different.
TL;DR: It was found that eugenol and penicillin produced a synergistic effect against S. pneumoniae in planktonic growth and within biofilms.
Abstract: In this study, we investigate the antimicrobial activities of both Eugenia caryophyllata (Ec) extract and its major component eugenol (4-allyl-2-methoxyphenol) against Streptococcus pneumoniae. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were determined by microdilution method. Pneumococcal biofilms were detected by crystal-violet microtiter plate assay, followed by colony-forming unit counts and visualized by scanning electron microscope (SEM). The synergistic effect of eugenol and penicillin was determined by checker-board method. Both the eugenol and the Ec extract inhibited pneumococcal growth in a concentration-dependent manner. The MIC and MBC of eugenol were 0.06% and 0.12%, respectively. Eugenol at a concentration of 0.12% completely killed S. pneumoniae within 60 min of exposure. The kill rate of planktonic cells was most rapid during the first 15 min of contact with eugenol. The addition of eugenol or Ec extract inhibited in vitro biofilm formation. In already established biofilms, the inhibitory effect of eugenol or Ec extract was more significant in terms of cell viability than in terms of disruption of the biofilm matrix. SEM analysis revealed non-viable and disruptive action of eugenol on the cell membrane of bacteria of biofilms. It was found that eugenol and penicillin produced a synergistic effect against S. pneumoniae. In conclusion, eugenol and Ec extract efficiently inhibited S. pneumoniae in planktonic growth and within biofilms.
TL;DR: Staphylococcus saprophyticus is a common urinary tract pathogen in young women, but its relative importance is low compared with E. coli even in this patient group.
Abstract: To determine the distribution of urinary tract pathogens with focus on Staphylococcus saprophyticus and analyse the seasonality, antibiotic susceptibility, and gender and age distributions in a large Swedish cohort. S. saprophyticus is considered an important causative agent of urinary tract infection (UTI) in young women, and some earlier studies have reported up to approximately 40% of UTIs in this patient group being caused by S. saprophyticus. We hypothesized that this may be true only in very specific outpatient settings. During the year 2010, 113,720 urine samples were sent for culture to the Karolinska University Hospital, from both clinics in the hospital and from primary care units. Patient age, gender and month of sampling were analysed for S. saprophyticus, Escherichia coli, Klebsiella pneumoniae and Proteus mirabilis. Species data were obtained for 42,633 (37%) of the urine samples. The most common pathogens were E. coli (57.0%), Enterococcus faecalis (6.5%), K. pneumoniae (5.9%), group B streptococci (5.7%), P. mirabilis (3.0%) and S. saprophyticus (1.8%). The majority of subjects with S. saprophyticus were women 15-29 years of age (63.8%). In this age group, S. saprophyticus constituted 12.5% of all urinary tract pathogens. S. saprophyticus is a common urinary tract pathogen in young women, but its relative importance is low compared with E. coli even in this patient group. For women in other ages and for men, growth of S. saprophyticus is a quite uncommon finding.
TL;DR: Careful review of polyomavirus biology may facilitate new discoveries concerning these formerly underestimated viral agents and their influence on human health.
Abstract: For almost 40 years, polyomavirus JC and BK were the only known human polyomaviruses but in the last 7 years, increased interest and innovative molecular screening techniques have led to the identification of 10 previously unknown polyomaviruses in humans. Two of these, Merkel cell polyomavirus and Trichodysplasia spinulosa polyomavirus, have also been found to cause disease in immunocompromised patients. Seroprevalence studies indicate that human polyomaviruses are transmitted independently of one another in humans and carry different risks of exposure and reexposure throughout life. The potential coexistence of 12 or more different polyomavirus species in the same host and possibly even in the same organ raises the question of potential interactions. Careful review of polyomavirus biology may facilitate new discoveries concerning these formerly underestimated viral agents and their influence on human health.