30 research outputs found

    Rapid Detection of Quinolone Resistance Mutations in gyrA of Helicobacter pylori by Real-Time PCR

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    The treatment of infections by the gastric pathogen Helicobacter pylori (H. pylori) has become more difficult due to increased rates of resistances against various antibiotics. Typically, atriple therapy, employing a combination of at least two antibiotics and a proton pump inhibitor, is used to cure H. pylori infections. In case of first-line therapy failure, quinolones are commonly applied in a second-line therapy. To prevent second-line treatment failures, we developed an improved method to detect the most common quinolone-resistance mutations located in the quinolone-resistance-determining region (QRDR) of the bacterial gyrA gene. Biopsy material from the gastric mucosa of infected patients was used to identify quinolone-resistant strains before the onset of drug administration. Two different wild-type and six mutant QRDR sequences were included. Melting curve analyses were performed with corresponding gyrA plasmid DNAs using a real-time polymerase chain reaction (RT-PCR) assay. By applying a combination of only two different fluorescent probes, this assay allows wild-type sequences to be unambiguously distinguished from all known mutant QRDR sequences of H. pylori. Next, the T(m) values of patient DNAs were established, and the genotypes were confirmed by sequencing. Thus, quinolone-resistant H. pylori strains can be easily and quickly diagnosed before treatment, which will help to avoid the administration of ineffective drug regimes

    Detection of Fusobacterium nucleatum in Patients with Colitis-Associated Colorectal Cancer

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    Fusobacterium nucleatum is supposed to play a critical role in the development of colorectal cancer. The species has also been associated with ulcerative colitis (UC) that can progress into colorectal cancer, however, the involvement of bacteria in this process remains unclear. We analysed 177 colon biopsies obtained from patients during screening, including 20 healthy controls, 56 UC cases and 69 cases at different stages of progression to colitis-associated cancer (CAC); 32 samples of sporadic colorectal carcinoma (sCRC) were also included. The presence of F.   nucleatum was detected by quantitative real-time PCR (qPCR). Our data show an association between the presence of the bacteria and the progression of carcinogenesis in UC patients. In 39.5% of CAC samples F. nucleatum was detected, compared to only 1.8% in UC cases. The bacteria were detected in 6.3% of samples with initial neoplastic transformation, so-called low-grade dysplasia (LGD), whereas high-grade dysplasia (HGD) resulted in 33.3% of samples positive for F. nucleatum . The fraction of F. nucleatum -positive samples from sCRC cases was 56.3%, which was not significantly different to the CAC group. We conclude that F. nucleatum is associated with the occurrence and progression of colon carcinogenesis, rather than with UC itself.Open Access funding enabled and organized by Projekt DEAL.Forschungskommission of the Klinikum BayreuthFriedrich-Alexander-Universität Erlangen-Nürnberg (1041

    Leukotriene Receptor Blockade as a Life-Saving Treatment in Severe Bronchopulmonary Dysplasia

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    Background: Bronchopulmonary dysplasia (BPD) is a major cause of mortality and morbidity in infants with an extremely low birth weight. Because there is no effective therapy, the mortality of this condition in severely affected patients is high. Therapeutic blocking of the leukotriene system seems to be a logical approach due to the known pathophysiology of BPD. Objectives: The aim of this study was to examine the therapeutic effect of montelukast in preterm children suffering from severe BPD. Methods: We performed an unblinded, prospective trial including infants born between 23 and 27 weeks of gestation suffering from severe BPD. The study drug was montelukast (1 mg/kg of body weight as a single dose daily in the 1st week of therapy, increasing to 1.5 mg/kg of body weight in the 2nd week and finally to 2 mg/kg of body weight in the 3rd week). Treatment was continued until the radiological signs and the clinical symptoms of BPD disappeared or the patient was discharged from the hospital. Each patient included in this study was matched for gestational age, birth weight, and pulmonary severity score to a control. Results: Until March 2014, a total of 22 infants were enrolled into the study. The rates of the primary outcome differed significantly between the montelukast-treated group and the control group. All but 1 of the children in the treatment group survived (91%), whereas 7 of the 11 children in the control group died (survival rate 36%; p = 0.002 using Fisher's exact test). The mean mechanical ventilation time (41.2 ± 25.3 vs. 103.7 ± 90.6 days) was significantly shorter and the mean preterm complication score (3.0 ± 1.7 vs. 5.6 ± 1.4) was significantly lower in treated patients compared to the control group. (p = 0.05 for both items; Wilcoxon's matched-pairs test). Conclusion: Based on the clinical observations, the statistical results, and the relatively low risk of the study drug montelukast, we recommend using this treatment in severe cases of BPD for infants facing a high risk of death

    Programmed death ligand 1 (PD-L1) in colon cancer and its interaction with budding and tumor-infiltrating lymphocytes (TILs) as tumor-host antagonists

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    Purpose To analyze the role of programmed death ligand 1 (PD-L1) immunohistochemisty in the context of tumor microenvironment in colon cancer (CC) with focus on the interaction between tumor budding and tumor-infiltrating lymphocytes (TILs) and to elucidate its potential value for immunooncologic treatment decisions. Methods Three hundred forty seven patients with CC, stages I to IV, were enrolled. PD-L1 immunohistochemistry was performed using two different antibodies (clone 22C3 pharmDx, Agilent and clone QR1, Quartett). Tumor proportion score (TPS) as well as immune cell score (IC) was assessed. Budding and TILs were assessed according to the criteria of the International Tumor Budding Consensus Conference (ITBCC) and International TILs Working Group (ITWG). Correlation analyses as well as survival analyses were performed. Results PD-L1 positivity significantly correlated with TILs > 5% and MMR deficiency, and PD-L1-positive cases (overall and IC) showed significantly longer overall survival (OS) with both antibodies.The parameters “high grade,” “right-sidedness,” and “TILS > 5% regardless of MMR status” evolved as potential parameters for additional immunological treatment decisions. Additionally, TPS positivity correlated with low budding. More PD-L1-positive cases were seen in both high TIL groups. The low budding/high TIL group showed longer disease-free survival and longer OS in PD-L1-positive cases. Conclusion Overall, PD-L1 positivity correlated with markers of good prognosis. PD-L1 immunohistochemistry was able to identify parameters as additional potential candidates for immune therapy. Furthermore, it was able to stratify patients within the low budding/high TIL group with significant prognostic impact

    Helicobacter Infection and Gastric Adenoma

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    Background: We aimed to provide insight into the actual frequencies of gastric adenoma types and their association with gastritis status and associated mucosal changes with a focus on Helicobacter infection and the operative link on gastritis assessment (OLGA)/operative link on gastric intestinal metaplasia assessment (OLGIM) staging. Methods: From the archive of the Institute of Pathology in Bayreuth, we collected a consecutive series of 1058 gastric adenomas diagnosed between 1987 and 2017. Clinicopathological parameters retrieved from diagnostic reports included adenoma type and localization, associated mucosal changes in antrum and corpus (i.e., type of gastritis, the extent of intestinal metaplasia and atrophy), gender, date of birth, and date of diagnosis. Results: Intestinal-type adenoma was the most frequent adenoma (89.1%), followed by foveolar-type adenoma (4.3%), pyloric gland adenoma (3.4%), adenomas associated with hereditary tumor syndromes (2.8%), and oxyntic gland adenoma (0.4%). Adenomas were found in the background of Helicobacter pylori (H. pylori) gastritis in 23.9%, Ex-H. pylori gastritis in 36.0%, autoimmune gastritis in 24.8%, chemical reactive gastritis in 7.4%, and others in 0.1%. More than 70% of patients with gastric adenomas had low-risk stages in OLGA and OLGIM. Conclusions: We found a higher frequency of foveolar-type adenoma than anticipated from the literature. It needs to be questioned whether OLGA/OLGIM staging can be applied to all patients

    Adjuvant chemotherapy in stage II and III colon cancer: the role of the “budding and TILs-(tumor-infiltrating lymphocytes) combination” as tumor-host antagonists

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    Purpose To analyze the influence of adjuvant chemotherapy on the combination of tumor budding and tumor-infiltrating lymphocytes (TILs) in stage II and III colon cancer and to elucidate its potential value for adjuvant treatment decisions. Methods 306 patients with stage II and 205 patients with stage III colon cancer diagnosed between 2005 and 2016 who had undergone surgery in a curative setting were enrolled. Budding and TILs were assessed according to the criteria of the International Tumor Budding Consensus Conference (ITBCC) and the criteria of the International TILs Working Group (ITWG). Combinations of budding and TILs were analyzed, and the influence of adjuvant chemotherapy was assessed. Results In stage II colon cancer, stratification into the four budding/TILs groups showed no significant differences in overall survival (OS) between the chemotherapy and the surgery-alone group, not even in cases with high-risk features. In stage III colon cancer, patients with low budding/high TILs benefited significantly from chemotherapy (p=0.005). Patients with high budding/low TILs as well as high budding/high TILs showed a trend to benefit from adjuvant treatment. However, no chemotherapy benefit was seen for the low budding/low TIL group. Conclusions The budding/TIL combination identified subgroups in stage II and III colon cancer with and without benefit from adjuvant treatment. The results this study suggest that the combination of budding and TILs as tumor-host antagonists might be an additional helpful tool in adjuvant treatment decisions in stage II and III colon cancer

    Clinical relevance of neuroendocrine differentiation in non-small cell lung cancer assessed by immunohistochemistry : a retrospective study on 405 surgically resected cases

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    Neuroendocrine differentiation in non-small cell lung cancer is a common feature, which has caused contradictory conclusions concerning survival estimates and responsiveness to therapy. Aiming to clarify this conflict, we analyzed neuroendocrine differentiation by immunohistochemistry in 405 surgically resected non-small cell lung carcinomas using standardized tissue microarray platform and the currently recommended antibody panel consisting of chromogranin-A, synaptophysin, and neural-cell adhesion molecule. Diagnostic criteria provided by the World Health Organization were applied. Histological subtypes were primarily reclassified according to current guidelines, assisted by auxiliary immunohistochemistry. Extensive clinical data was acquired, enabling detailed clinicopathological correlation. Importantly, neuroendocrine differentiation assessed by immunohistochemistry showed no significant relation to overall survival estimates, which remained unaffected by histological subtype, neuroendocrine marker type, adjuvant therapy, and recurring disease. The only exception was a small group consisting of three large cell carcinomas, each expressing all three neuroendocrine markers and demonstrating decreased survival. In conclusion, additional immunohistochemical detection of neuroendocrine differentiation in non-small cell lung cancer is presently not of prognostic importance and does not justify a distinct consideration
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