Apmis

KRONVALL, GÖRAN

doi: 10.1111/j.1600-0463.2010.02660.xpmid: 20718714

Kronvall G. Antimicrobial resistance 1979–2009 at Karolinska hospital, Sweden: normalized resistance interpretation during a 30‐year follow‐up on Staphylococcus aureus and Escherichia coli resistance development. APMIS 2010; 118: 621–39. To utilize a material of inhibition zone diameter measurements from disc diffusion susceptibility tests between 1979 and 2009, an objective setting of epidemiological breakpoints was necessary because of methodological changes. Normalized resistance interpretation (NRI) met this need and was applied to zone diameter histograms for Staphylococcus aureus and Escherichia coli isolates. The results confirmed a slow resistance development as seen in Northern countries. The S. aureus resistance levels for erythromycin, clindamycin and fusidic acid in 2009 were 3.2%, 1.8% and 1.4% with denominator correction. A rise in resistance to four antimicrobials in 1983 was probably because of a spread of resistant Methicillin Susceptible Staphylococcus Aureus (MSSA). For E. coli, the denominator‐corrected resistance levels in 2009 were 27% for ampicillin, around 3% for third‐generation cephalosporins, 0.1% for imipenem, 2.5% for gentamicin, 19% for trimethoprim, 4.5% for co‐trimoxazole, 1.2% for nitrofurantoin and 9% for ciprofloxacin. The temporal trends showed a rise in fluoroquinolone resistance from 1993, a parallel increase in gentamicin resistance, a substantial increase in trimethoprim and sulphonamide resistance in spite of decreased consumption, and a steady rise in ampicillin resistance from a constant level before 1989. A short review of global resistance surveillance studies is included.

VÄRE, PÄIVI; SOINI, YLERMI

doi: 10.1111/j.1600-0463.2010.02638.xpmid: 20718715

Väre P, Soini Y. Twist is inversely associated with claudins in germ cell tumors of the testis. APMIS 2010; 118: 640–7. We investigated the expression of claudins 1, 3–7 and transcriptional factor twist in a set of testicular germ cell tumors. The material consisted of 17 seminomas, 13 teratomas, 9 teratocarcinomas, 20 embryonal carcinomas and 9 mixed germ cell tumors. They were immunostained with antibodies to claudins 1, 3–7 and twist. As expected, all claudins were variably present in germ cell tumors with epithelial elements or differentiation, but the intensity of expression varied depending on the claudin type. Mesenchymal elements in teratomatous tumors remained negative for claudins. Expression of different claudins was less intense and inconsistent in other types of germ cell tumors. Choriocarcinomatous elements in germ cell tumors expressed relatively strongly claudin 4 and weaker positivity for claudins 5–7, while claudins 1 and 3 were negative. Seminomas showed expression only for claudins 5 and 7. The transcriptional factor twist was most strongly expressed in seminoma followed by embryonal carcinoma. Twist expression was inversely associated with several claudins (claudins 1, 3, 4 and 6). Germ cell tumors vary in their expression of claudins 1–7. Twist expression was inversely associated with several claudins, suggesting that it takes part in the downregulation of claudins in testicular tumors.

TRYGGVASON, GEIR; HILMARSDOTTIR, BYLGJA; GUNNARSSON, GUðMUNDUR H.; JÓNSSON, JÓN JÓHANNES; JÓNASSON, JÓN G.; MAGNÚSSON, MAGNÚS K.

doi: 10.1111/j.1600-0463.2010.02643.xpmid: 20718716

Tryggvason G, Hilmarsdottir B, Gunnarsson GH, Jónsson JJ, Jónasson JG, Magnússon MK. Tyrosine kinase mutations in gastrointestinal stromal tumors in a nation‐wide study in Iceland. APMIS 2010; 118: 648–56. Gastrointestinal stromal tumor (GIST) is the most common mesenchymal tumor of the gastrointestinal tract. It is characterized by activating mutations in the tyrosine kinase genes c‐kit or PDGFRA. This study examined the mutation rate and type in a population‐based material. All gastrointestinal mesenchymal tumors over the years 1990–2004 were evaluated and GIST tumors identified using immunohistochemistry (c‐kit) and conventional pathologic parameters. Paraffin sections from all tumors were subjected to mutation analysis on exons 9, 11, 13 and 17 of the c‐kit gene and exons 12 and 18 of the PDGFRA gene. To screen for mutations, we used a highly sensitive conformation‐sensitive gel electrophoresis (CSGE) and to define the mutated alleles, we employed direct automated DNA sequencing. All c‐kit‐positive gastrointestinal mesenchymal tumors were entered into the study. Fifty‐six tumors from 55 patients were analyzed. Mutations were found in 52 tumors representing a 92.9% mutational rate. Most of the mutations were found in c‐kit exon 11 (76.8%), followed by c‐kit exon 9 (10.7%). PDGFRA mutations were only found in three tumors. No correlation of mutation type with biologic behavior was found. This population‐based study, using a sensitive CSGE method, identifies mutations in the great majority of patients with GIST.

LIU, QIUYU; HAN, ANJIA; YOU, SHUYUAN; YANG, QINGXU; LIANG, YINGJIE; DONG, YU

doi: 10.1111/j.1600-0463.2010.02642.xpmid: 20718717

Liu Q, Han A, You S, Yang Q, Liang Y, Dong Y. The association of genomic variation of Epstein–Barr virus BamHI F fragment with the proliferation of nasopharyngeal carcinoma. APMIS 2010; 118: 657–64. To investigate the f variant of Epstein–Barr virus (EBV) in nasopharyngeal carcinogenesis, we detected the f variant in primary nasopharyngeal carcinoma (NPC), metastatic carcinoma of the lymph node (LN), and chronic inflammation of the nasopharynx from the Guangdong region. Meanwhile, we analyzed the relationship between the f variant of EBV and LMP1, Fascin, pStat3, p53, Bcl‐2, and Ki‐67 expression in NPC. The results showed that the f variant of EBV was found in 11 cases of primary NPCs with LN metastasis, 12 LN metastases, and 18 primary NPCs without LN metastasis. However, only one demonstrated the F/f variant in 50 cases of chronic inflammation of the nasopharynx. The expression rate of LMP1, Fascin, pStat3, p53, Bcl‐2, and Ki‐67 in NPC with the f or F/f variant was higher than that with the F prototype. Furthermore, there was a significantly positive correlation between the f variant of EBV and Ki‐67 expression (p < 0.05). Our study suggests that the f variant of EBV may be closely related to nasopharyngeal carcinogenesis.

YRJÄNÄINEN, HETA; HYTÖNEN, JUKKA; HARTIALA, PAULIINA; OKSI, JARMO; VILJANEN, MATTI K.

doi: 10.1111/j.1600-0463.2010.02615.xpmid: 20718718

Yrjänäinen H, Hytönen J, Hartiala P, Oksi J, Viljanen MK. Persistence of borrelial DNA in the joints of Borrelia burgdorferi‐infected mice after ceftriaxone treatment. APMIS 2010; 118: 665–73. We have earlier shown that Borrelia burgdorferi‐infected and ceftriaxone‐treated mice have viable spirochetes in their body, since immunosuppressive treatment allows B. burgdorferi to be detected by culture. However, the niche of the persisting spirochetes remained unknown. In the present study, we analyzed the tissues of B. burgdorferi‐infected and ceftriaxone‐treated mice by culture and PCR to reveal the foci of persisting spirochetes. C3H/HeN mice were infected via intradermal needle injection with B. burgdorferi s.s. N40. The mice were treated as follows: (i) short (5 days) and (ii) long (18 days) course of ceftriaxone at 2 weeks of infection and killed after either 10 or 30 weeks, or (iii) the mice received ceftriaxone for 5 days at 18 weeks of infection and were killed 21 weeks after the treatment. All samples of ceftriaxone‐treated mice were culture negative, whereas all untreated controls were culture positive. Importantly, B. burgdorferi DNA was detected in the joints of 30–100% of the treated mice. In conclusion, these results combined with earlier results suggest that the joint or a tissue adjacent to the joint is the niche of persisting B. burgdorferi in ceftriaxone‐treated mice.

SAVOIA, DIANELLA; DONALISIO, MANUELA; CIVRA, ANDREA; SALVADORI, SEVERO; GUERRINI, REMO

doi: 10.1111/j.1600-0463.2010.02637.xpmid: 20718719

Savoia D, Donalisio M, Civra A, Salvadori S, Guerrini R. In vitro activity of dermaseptin S1 derivatives against genital pathogens. APMIS 2010; 118: 674–80. The aim of this study was to evaluate the biological activity of nine dermaseptin‐S1 (DRS‐S1) derivatives (synthesized by solid‐phase methods and purified) against different pathogens causing genital infections (Trichomonas vaginalis, Herpes simplex virus, Papillomavirus). The in vitro activity on T. vaginalis was determined by counting the protozoon in a hemocytometer after vital staining with trypan blue; antiviral activity of the compounds was tested on monolayers of Vero cells for Herpes simplex virus‐1 (GFP) and on 293TT cells for human papillomavirus (HPV‐16) pseudovirions (GFP). The cytotoxicity of the derivatives was assessed by evaluating both the hemolytic activity and the effect on Vero and 293TT cells. The DRS‐S1 longer peptides demonstrated a superior activity on T. vaginalis but also a certain cytopathic effect. The compounds with 29 amino acids exhibited activity against the two viruses tested at concentrations not toxic to cells. The results obtained show that some of the synthetic peptides assessed have inhibitory activity against the pathogens tested, indicating a potential for the development of new molecules for use as topical microbicides to prevent the sexual transmission of microorganisms.

Galan‐Sanchez, Fatima; Rodriguez‐Iglesias, Manuel A.

doi: 10.1111/j.1600-0463.2010.02639.xpmid: 20718720

Galan‐Sanchez F, Rodriguez‐Iglesias MA. Use of Cervista HPV HR assay for detection of human papillomavirus in samples with hybrid capture borderline negative results. APMIS 2010; 118: 681–4. We have evaluated Cervista HPV HR for papillomavirus detection in 65 samples previously borderline negative by the hybrid capture method (Digene), using InnoLipa and sequencing as confirmatory techniques. Nine samples were found to be positive by Cervista HPV HR, of which five (7.6%) were confirmed by InnoLipa. Four samples (6.1%) were false positive, of which three samples were reactive for A9 probes. The Cervista HPV HR assay can detect HPV‐positive samples from those with hybrid capture borderline results but can produce false‐positive results when tested for reactivity with A9 probes.

XU, YINGHUA; XU, YUNQIANG; HOU, QIMING; YANG, RUIFU; ZHANG, SHUMIN

doi: 10.1111/j.1600-0463.2010.02644.xpmid: 20718721

Xu Y, Xu Y, Hou Q, Yang R, Zhang S. Triplex real‐time PCR assay for detection and differentiation of Bordetella pertussis and Bordetella parapertussis. APMIS 2010; 118: 685–91. A triplex real‐time PCR assay for detection and differentiation of Bordetella pertussis and Bordetella parapertussis was developed. Three targets were used for amplification in a single tube: the insertion sequence IS481 and the pertussis toxin promoter region (ptxP) for B. pertussis, and the insertion sequence IS1001 for B. parapertussis. The performance of this PCR assay was evaluated in parallel in three single‐target real‐time PCR assays using DNA extracted from B. pertussis and B. parapertussis reference strains and nasopharyngeal swabs taken from 105 patients who had been coughing for more than 7 days. The minimum detection limit of the triplex PCR was one to five colony‐forming units (CFU) of B. pertussis and 1 CFU of B. parapertussis per reaction, and the coefficients of both intra‐ and inter‐assay variation were less than 7%. Results were available within 4 h. Of the 105 nasopharyngeal samples, seven were culture positive and 23 were PCR positive for B. pertussis. All culture‐positive samples were also PCR positive. Our single‐tube triplex real‐time PCR assay proved to be sensitive, specific and suitable for simultaneous detection and discrimination of B. pertussis and B. parapertussis.

Botros, Sanaa S.; Hammam, Olfat; Mahmoud, Madiha; Bergquist, Robert

doi: 10.1111/j.1600-0463.2010.02645.xpmid: 20718722

Botros SS, Hammam O, Mahmoud M, Bergquist R. Praziquantel efficacy in mice infected with PZQ non‐susceptible S. mansoni isolate treated with artemether: parasitological, biochemical and immunohistochemical assessment. APMIS 2010; 118: 692–702. Based on the fact that artemether (ART) affects immature schistosomes and that the effect of praziquantel (PZQ) mainly targets mature schistosomes, this work investigates the possible enhanced efficacy of PZQ in combination with ART in mice harboring a PZQ non‐susceptible Schistosoma mansoni isolate. Associated schistosomal, inflammatory, hepatic histopathological changes have been investigated by examining the tissue markers expressing apoptosis using FAS (CD95), anti‐apoptosis (Bcl2) and angiogenesis (vascular endothelial growth factor (VEGF)). A batch of Swiss albino mice infected with a PZQ non‐susceptible (EE10) S. mansoni isolate was divided into 12 groups. Animals of the first group were left without treatment as infected controls, while groups 2–6 received PZQ in increasing doses. The animals of group 7 received ART in double doses. Those comprising groups 8–12 received combined therapy of PZQ and ART in the same doses and at the same timings postinfection (PI) as those belonging to groups 2–6. Parasitological parameters, liver function, and histopathological and immunohistochemical studies of FAS, Bcl2 and VEGF antibodies were assessed. Combined administration of ART and PZQ reduced the ED50 (the dose at which the worm burden was decreased by 50%) of PZQ. Typical granulomas were not seen in animals treated with ART alone and combined with PZQ, with least expression of FAS and VEGF and increased expression of Bcl2. The minimal histopathological changes recorded in mice treated with both ART and PZQ could be related to a synergistic/additive effect of ART, markedly reducing the intensity of infection. Improved liver function tests support the less severe histopathological changes under the influence of this treatment protocol. This study encourages human trials especially in areas where malaria is not endemic, and differing combination doses should be investigated in view of the antagonistic effect noticed with some dose regimens.

MAZUR, WITOLD; LINDHOLM, PAMELA; VUORINEN, KIRSI; MYLLÄRNIEMI, MARJUKKA; SALMENKIVI, KAISA; KINNULA, VUOKKO L.

doi: 10.1111/j.1600-0463.2010.02646.xpmid: 20718723

Mazur W, Lindholm P, Vuorinen K, Myllärniemi M, Salmenkivi K, Kinnula VL. Cell‐specific elevation of NRF2 and sulfiredoxin‐1 as markers of oxidative stress in the lungs of idiopathic pulmonary fibrosis and non‐specific interstitial pneumonia. APMIS 2010; 118: 703–12. Human idiopathic pulmonary fibrosis (IPF) and non‐specific interstitial pneumonia (NSIP) have been proposed to be attributable to oxidative stress. The nuclear factor, erythroid derived 2, like protein (NRF2)–sulfiredoxin‐1 (SRX1) pathway was hypothesized to be associated with the pathogenesis of human pulmonary fibrosis. Several methods including digital morphometry were used in the assessment of the cell‐specific localization and expression of NRF2 and SRX1 and selected proteins linked to their activation/stability in human IPF/usual interstitial pneumonia (UIP) and NSIP lung. The proteins of the NRF2 pathway were localized in the hyperplastic alveolar epithelium and inflammatory cells in IPF and NSIP, but were absent in the fibroblastic foci characteristic of IPF. Morphometric evaluation revealed NRF2 and KEAP1 to be significantly elevated in the hyperplastic alveolar epithelium compared with the normal alveolar epithelium, and NRF2 was remarkably expressed in the nuclear compartment of the hyperplastic cells. SRX1 was expressed mainly in alveolar macrophages, and the number of SRX1‐positive macrophages/surface area was elevated in NSIP, a disease which contains more marked inflammatory reaction compared with the IPF/UIP lung. The expression of the NRF2 pathway in human IPF and NSIP is further evidence that the pathogenesis of human fibrotic lung diseases is oxidant‐mediated and originates from the alveolar epithelium.