Apmis

BATOULIS, HELENA; RECKS, MASCHA S.; ADDICKS, KLAUS; KUERTEN, STEFANIE

doi: 10.1111/j.1600-0463.2011.02794.xpmid: 22085358

Batoulis H, Recks MS, Addicks K, Kuerten S. Experimental autoimmune encephalomyelitis – achievements and prospective advances. APMIS 2011; 119: 819–30. Multiple sclerosis (MS) is an autoimmune disorder of the CNS. Different subtypes of the disease have been noted, and characterized by distinct clinical courses and histopathologic manifestations. The most intensively studied animal model of MS, experimental autoimmune encephalomyelitis (EAE), classically leads to deficits in motor functions, and is mediated by T helper cells. Recently, TH17 cells were ascribed an even greater pathogenic impact than TH1 cells, but new findings render this view controversial. Although classic EAE has been an invaluable tool, it does not cover the entire pathogenic entity of MS. Especially B‐cell contribution and autoantibody‐dependence are not mirrored adequately: therefore, new B‐cell‐dependent models, such as MP4‐induced EAE, have been introduced. Furthermore, certain symptoms and the spontaneous onset of MS are not featured in classic EAE. Herein, atypical and spontaneous EAE models can be used for investigation of common symptoms, such as tremor and ataxia, as well as spontaneous disease development. MS displays a marked inter‐individual heterogeneity, and no single model will be able to cover all features. Thus, depending on the objective of one’s study, the appropriate EAE model has to be carefully chosen. In addition, refined models should be designed to gain a more complete understanding of MS.

NASSEHI, DAMOUN; DYRBYE, HENRIK; ANDRESEN, MORTEN; THOMSEN, CARSTEN; JUHLER, MARIANNE; LAURSEN, HENNING; BROHOLM, HELLE

doi: 10.1111/j.1600-0463.2011.02764.xpmid: 22085359

Nassehi D, Dyrbye H, Andresen M, Thomsen C, Juhler M, Laursen H, Broholm H. Vascular endothelial growth factor A protein level and gene expression in intracranial meningiomas with brain edema. APMIS 2011; 119: 831–43. Meningiomas are the second most common primary intracranial tumors in adults. Although meningiomas are mostly benign, more than 50% of patients with meningioma develop peritumoral brain edema (PTBE), which may be fatal because of increased intracranial pressure. Vascular endothelial growth factor (VEGF) is an endothelial cell‐specific mitogen and angiogen. VEGF‐A protein, which is identical to vascular permeability factor, is a regulator of angiogenesis. In this study, 101 patients with meningiomas, and possible co‐factors to PTBE, such as meningioma subtypes and tumor location, were examined. Forty‐three patients had primary, solitary, supratentorial meningiomas with PTBE. In these, correlations in PTBE, edema index, VEGF‐A protein, VEGF gene expression, capillary length, and tumor water content were investigated. DNA‐branched hybridization was used for measuring VEGF gene expression in tissue homogenates prepared from frozen tissue samples. The method for VEGF‐A analysis resembled an ELISA assay, but was based on chemiluminescence. The edema index was positively correlated to VEGF‐A protein (p = 0.014) and VEGF gene expression (p < 0.05). The capillary length in the meningiomas was positively correlated to the PTBE (p = 0.038). If VEGF is responsible for the formation of PTBE, the edema may be treated with the anti‐VEGF drug Bevacizumab (Avastin), which has been shown to reduce PTBE in patients with glioblastoma multiforme.

TVEDSKOV, TOVE FILTENBORG; BARTELS, ANNETTE; JENSEN, MAJ‐BRITT; PAASCHBURG, BIRGITTE; KROMAN, NIELS; BALSLEV, EVA; BRÜNNER, NILS

doi: 10.1111/j.1600-0463.2011.02768.xpmid: 22085360

Tvedskov TF, Bartels A, Jensen M‐B, Paaschburg B, Kroman N, Balslev E, Brünner N. Evaluating TIMP‐1, Ki67 and HER2 as markers for non‐sentinel node metastases in breast cancer patients with micrometastases to the sentinel node. APMIS 2011; 119: 844–52. The aim was to investigate whether the biochemical prognostic markers TIMP‐1, Ki67, and HER2 could predict metastatic spread to non‐sentinel nodes (NSN) in breast cancer patients with micrometastases to sentinel node (SN). We included all breast cancer patients with micrometastases to SN operated between 2001 and 2007 at the Department of Breast Surgery, Herlev Hospital. The study was designed as a matched case–control study with 25 cases with micrometastases to SN and, in addition, metastatic spread to NSN and 50 matched controls with micrometastases to SN, but without NSN metastases. Patient and tumor characteristics were retrieved from the Danish Breast Cancer Cooperative Group database. Immunohistochemical analyses of TIMP‐1 and Ki67 and measurements of HER2 on formalin‐fixed paraffin‐embedded tumor tissue were performed. No significant differences in the immunoreactivity of TIMP‐1 and Ki67 were found between patients with and without NSN metastases. Six of seven HER2 positive patients did not have NSN metastases, but the results did not reach statistical significance. Despite being prognostic markers in breast cancer, TIMP‐1 and Ki67 could not predict NSN metastases in women with micrometastatic disease to SN. Larger studies are needed to further validate HER2 as a marker for NSN metastases in these patients.

TITELMAN, EMILIA; IVERSEN, AINA; KAHLMETER, GUNNAR; GISKE, CHRISTIAN G.

doi: 10.1111/j.1600-0463.2011.02766.xpmid: 22085361

Titelman E, Iversen A, Kahlmeter G, Giske CG. Antimicrobial susceptibility to parenteral and oral agents in a largely polyclonal collection of CTX‐M‐14 and CTX‐M‐15‐producing Escherichia coli and Klebsiella pneumoniae. APMIS 2011; 119: 853–63. Activity of oral and parenteral antimicrobials against consecutively isolated extended‐spectrum β‐lactamase (ESBL)‐producing Escherichia coli (n = 149) and Klebsiella pneumoniae (n = 20) was determined, and susceptibility test methods were compared for parenteral β‐lactams. Polymerase chain reaction (PCR) targeting blaCTX‐M, blaSHV and blaTEM, and DNA sequencing and epidemiological typing with pulsed‐field gel electrophoresis were performed. PCR targeting pabB was screened for E. coli O25b‐ST131. Minimum inhibitory concentrations (MICs) were determined using Etest and broth microdilution. Disc diffusion was performed according to European Committee on Antimicrobial Susceptibility Testing (EUCAST). Dominating genotypes were blaCTX‐M‐15 (75%) and blaCTX‐M‐14 (23%). Four E. coli clusters (7–18 isolates) were found. Forty‐two per cent of E. coli belonged to O25b‐ST131. Ciprofloxacin resistance was 72%, trimethoprim resistance was 70%. Among E. coli, resistance to mecillinam (13%), nitrofurantoin (7%) and fosfomycin (3%) was low, although resistance was high in K. pneumoniae (25%, 60%, 85%). Susceptibility to ertapenem was 99%, piperacillin‐tazobactam 91%, tigecycline 96% and temocillin 76%. Susceptibility rates obtained with broth microdilution and Etest were in agreement for cefotaxime (2 vs 1%) and ceftazidime (9 vs 11%), but not for piperacillin‐tazobactam (59 vs 91%). With disc diffusion major errors occurred with piperacillin‐tazobactam (18/169). Several therapeutic alternatives exist for ESBL‐producing E. coli, but few exist for K. pneumoniae. Disc diffusion and Etest can accurately predict susceptibility to cefotaxime and ceftazidime, but not to piperacillin‐tazobactam with the present breakpoints.

OUZOUNOVA‐RAYKOVA, VESSELA; JORDANOV, DANIEL; EL‐TIBI, MOHAMED; MITOV, IVAN

doi: 10.1111/j.1600-0463.2011.02769.xpmid: 22085362

Ouzounova‐Raykova V, Jordanov D, El‐Tibi M, Mitov I. Gonococcal infection in symptomatic and asymptomatic persons seeking medical clinics in Sofia. A 3‐year study 2008–2010. APMIS 2011; 119: 864–7. The aim was to determine the prevalence of gonococcal infection and to compare the results with those received by other researchers, because in Bulgaria a good medical practice for the laboratory confirmation, report and therapy is lacking. A total of 617 specimens from symptomatic and asymptomatic persons attending clinics in Sofia from January 2008 to December 2010 were tested by culture and in‐house PCR. Using PCR Neisseria gonorrhoeae was identified in six urethral (6.25%) and eight (1.54%) cervical specimens. By applying culture method, N. gonorrhoeae positive result was found in 12 swabs – one cervical and one urethral swab less. The positive results correspond predominantly to persons with genital complains and suspicions for gonococcal or other sexually transmitted infection. This is the first study in Bulgaria since 1989 and determines the prevalence of N. gonorrhoeae to 2.3% over a 3‐year period. Detection by culture was slightly less sensitive than by nucleic acid amplification test (NAAT). Continuous monitoring of gonorrhea by culture and NAAT is important for public health in Bulgaria.

AHN, CHI YOUNG; KIM, SE HOON; JANG, SEON JUNG; HONG, SOON WON; KIM, HYUNKI; LIM, BEOM JIN

doi: 10.1111/j.1600-0463.2011.02795.xpmid: 22085363

Ahn CY, Kim SH, Jang SJ, Hong SW, Kim H, Lim BJ. A mathematical approach to the optimal examination of lymph nodes. APMIS 2011; 119: 868–76. There is no scientific evidence to support the idea that serial sectioning along the short axis of the lymph node is superior to a single bisection along the long axis. We mathematically evaluated methods of lymph node dissection and applied the result to six lymph nodes that had produced false negative results at the time of frozen examination. We simplified the geometry of a lymph node to that of a three‐dimensional ellipse and compared two different cutting methods. Let A be the cross‐sectional area obtained through a single bisection along the long axis, and let B be the sum of the cross‐sectional areas of n fragments obtained via serial cutting along the short axis. The smallest n (n*) that makes a B larger than A can be calculated. (, the smallest integer greater than or equal to α; L, long axis; S, short axis). The probabilities of tumor detection when the node is bisected along the long axis (P(DA|E)) and when serially cut along the short axis (P(DB|E)) are as follows. and (T, size of the tumor cell cluster). According to these formulas, three out of six lymph nodes were not examined in the most appropriate manner.

TRAPECAR, MARTIN; LEOUFFRE, THOMAS; FAURE, MORGANE; JENSEN, HENRIK E; GRANUM, PER E; CENCIC, AVRELIJA; HARDY, SIMON P

doi: 10.1111/j.1600-0463.2011.02797.xpmid: 22085364

Trapecar M, Leouffre T, Faure M, Jensen HE, Granum PE, Cencic A, Hardy SP. The use of a porcine intestinal cell model system for evaluating the food safety risk of Bacillus cereus probiotics and the implications for assessing enterotoxigenicity. APMIS 2011; 119: 877–84. The use of porcine intestinal cell lines in assessing toxicity of Bacillus cereus probiotics in conjunction with animal challenge trials with toxigenic B. cereus was investigated. Toxigenic and toxin deletion mutants of B. cereus and two probiotic strains (Paciflor and Toyocerin) were examined for bacterial attachment, cytotoxicity and ability to induce nitric oxide as markers of toxicity. Both cytotoxicity and production of nitric oxide were detected in wild‐type toxigenic strains and the Paciflor probiotic strain but not Toyocerin. Attachment of B. cereus was low (less than 1%) in all strains. Discrimination between toxigenic B. cereus and the probiotic strains was possible semi‐quantitatively via dilution. Despite cytotoxicity in vitro, challenge experiments using 108–109 spores of the toxigenic B. cereus NVH75/95 in weaned piglets did not induce diarrhoea or intestinal lesions. Thus, the pig small intestinal epithelial intestinal cell line PSI is appropriate for identification of potential toxicity in B. cereus strains and sets a low threshold for risk of enterotoxicity to humans.

SVENSSON, KAROLINA; HELLMARK, BENGT; SÖDERQUIST, BO

doi: 10.1111/j.1600-0463.2011.02801.xpmid: 22085365

Svensson K, Hellmark B, Söderquist B. Characterization of SCCmec elements in methicillin‐resistant Staphylococcus epidermidis isolated from blood cultures from neonates during three decades. APMIS 2011; 119: 885–93. Staphylococcus epidermidis is a major cause of nosocomial infections in immunocompromised patients and the predominant pathogen in catheter‐related infections and bloodstream infections. Approximately 70–80% of S. epidermidis carry the mecA gene encoding methicillin resistance. The mecA gene is located on a mobile genetic element, the staphylococcal cassette chromosome mec (SCCmec). The aim of this study was to characterize the SCCmec elements as well as the adjacent arginine catabolic mobile element (ACME) in 30 clinical blood isolates of mecA positive S. epidermidis obtained from neonates and collected over a period of three decades. The ccr and mec gene complexes were identified using PCR. The SCCmec elements were found among 29/30 isolates and 13 different combinations of ccr gene complexes and mec gene complexes were identified. Staphylococcus epidermidis regularly carried multiple copies of ccr gene complexes, but only one class of mec gene complex. Three isolates could be assigned the SCCmec type III (3A). The combinations of ccr gene complexes and the mec gene complexes differed among the three decades. The most frequent combination was class B mec in combination with ccr1 and ccr2. Staphylococcus epidermidis may constitute a large reservoir for SCCmec elements, and frequent exchange of mobile genetic elements between staphylococcal species may explain the emergence of new MRSA strains.

MUBARAK, A; GMELIG‐MEYLING, FHJ; WOLTERS, VM; TEN KATE, FJW; HOUWEN, RHJ

doi: 10.1111/j.1600-0463.2011.02817.xpmid: 22085366

Mubarak A, Gmelig‐Meyling FHJ, Wolters VM, Ten Kate FJW, Houwen RHJ. Immunoglobulin G antibodies against deamidated‐gliadin‐peptides outperform anti‐endomysium and tissue transglutaminase antibodies in children <2 years. APMIS 2011; 119: 894–900. To investigate the usefulness of deamidated‐gliadin‐peptides‐antibodies in the diagnosis of celiac disease, serology was tested in 212 children suspected with celiac disease who had undergone a small‐intestinal‐biopsy. For deamidated‐gliadin‐peptides‐antibodies, two kits were tested. Positive and negative predictive values for IgA deamidated‐gliadin‐peptides‐antibodies using the Bindazyme‐kit were 89% and 74%, while the Quanta‐Lite‐kit had values of 89% and 85%, respectively. For the IgG subtype using the Bindazyme‐kit, these values were 85% and 89%, while they were 85% and 91% for the Quanta‐Lite‐kit. The positive predictive values for endomysium and tissue‐transglutaminase antibodies were disappointing (77% and 87%), although the negative predictive values were better (97% and 96%). When the analysis was restricted to the 41 children aged <2 years, no misclassifications occurred with IgG deamidated‐gliadin‐peptides‐antibodies giving 100% accuracy in both kits. The positive predictive value reached 100% for tissue‐transglutaminase antibodies and both kits for IgA deamidated‐gliadin‐peptides‐antibodies, while the negative predictive value was 94% in these assays. Positive and negative predictive values for endomysium antibodies were 96% and 93%, respectively. In conclusion, although deamidated‐gliadin‐peptides‐antibodies do not outperform anti‐endomysium antibodies in the total study population, the IgG subtype seems to be the best test in children aged <2 years, reaching 100% accuracy.

Gomes, Milene Barbosa; Rodrigues, Ana Claudia Souza; Assef, Ana P D C; De Filippis, Ivano; Asensi, Marise Dutra; Zahner, Viviane

doi: 10.1111/j.1600-0463.2011.02805.xpmid: 22085367