Soft tissue metastasis of mediastinal non-functioning paraganglioma with unusual TTF-1 expression: a potential diagnostic pitfall.

Metastatic extra-adrenal paragangliomas are very rare and can represent diagnostic challenges. We report a case of 69-year-old man with a tumor of the right shoulder. Histologic and immunohistochemical examinations confirmed the diagnosis of paraganglioma. Surprisingly, tumor cells were diffusely thyroid transcription factor 1 (TTF-1) positive. Succinate dehydrogenase complex subunit B (SDHB) deficiency has not been detected. Inherited syndromes associated with paragangliomas were ruled out. The primary tumor was identified in the mediastinum. This is the first report of TTF-1 expression in paraganglioma. To avoid misdiagnosis, careful clinical and pathological examination of any tumor with organoid growths pattern is necessary.

Overexpression of c-Myb is associated with suppression of distant metastases in colorectal carcinoma.

The MYB gene codes for the c-Myb transcription factor maintaining proliferation of colon epithelial progenitors, thus controlling colon development and homeostasis. This gene is overexpressed in early phases of colorectal cancer (CRC) tumorigenesis. The aim of this study was to examine the expression of c-Myb in CRC tissue samples both at the messenger RNA (mRNA) and protein levels and to evaluate their associations with clinicopathological characteristics in a group of 108 CRC patients. Statistically significant negative association was found between the frequency of the c-Myb-positive tumor cells assessed by immunohistochemistry and the presence of distant metastases (p < 0.01) but not tumor differentiation, tumor stage, lymph node involvement, vascular invasion, tumor localization, age, and gender of the patients. Although the c-Myb protein level in the tumor tissue correlated with its mRNA level, no significant association between MYB mRNA and any clinicopathological characteristics was observed. We conclude that albeit overexpression of c-Myb is considered as an important factor contributing to early phases of CRC tumorigenesis, it may later have negative effect on tumor cell dissemination as observed recently in breast cancer as well. Further studies are required to explain the role of c-Myb during formation of CRC distant metastases.

Intravenous insulin therapy during lung resection does not affect lung function or surfactant proteins.

BACKGROUND: The surgical resection of lung disrupts glucose homeostasis and causes hyperglycemia, as in any other major surgery or critical illness. We performed a prospective study where we carefully lowered hyperglycemia by insulin administration during the surgery, and for the first time we monitored immediate insulin effects on lung physiology and gene transcription. METHODS: The levels of blood gases (pH, pCO2, pO2, HCO3-, HCO3- std, base excess, FiO2, and pO2/FiO2) were measured at the beginning of surgery, at the end of surgery, and two hours after. Samples of healthy lung tissue surrounding the tumour were obtained during the surgery, anonymized and sent for subsequent blinded qPCR analysis (mRNA levels of surfactant proteins A1, A2, B, C and D were measured). This study was done on a cohort of 64 patients who underwent lung resection. Patients were randomly divided, and half of them received insulin treatment during the surgery. RESULTS: We demonstrated for the first time that insulin administered intravenously during lung resection does not affect levels of blood gases. Furthermore, it does not induce immediate changes in the expression of surfactant proteins. CONCLUSION: According to our observations, short insulin treatment applied intravenously during resection does not affect the quality of breathing.

High c-Myb Expression Associates with Good Prognosis in Colorectal Carcinoma.

Colorectal cancer (CRC) represents a serious challenge for oncologists due to high incidence and large heterogeneity. Prognostic factors are needed to stratify patients according to risk of disease progression. In this study, we report that high expression of c-Myb protein, determined by immunohistochemistry (IHC), associates with better overall and disease-free survival (OS, DFS) in a cohort of 103 patients. Although MYB has been previously considered to act as oncogene in CRC, our further analysis of datasets deposited in PrognoScan and SurvExpress databases confirmed that high MYB expression largely associates with good prognosis in CRC. As therapies targeting c-Myb have been developed and tested in preclinical studies, we believe that further studies are needed for detailed understanding of c-Myb function in CRC, before the c-Myb-targeted therapy enters clinical trials.

Postintubation tracheal rupture: case report.

Tracheobronchial rupture after tracheal intubation has been infrequently reported. Successful diagnosis often requires a high level of suspicion. A laceration of the distal membranous trachea usually has been repaired through a right thoracotomy.

Neovascularization after ischemic conditioning of the stomach and the influence of follow-up neoadjuvant chemotherapy thereon.

INTRODUCTION: Esophagectomy and reconstruction remain the optimal treatment for patients with resectable esophageal cancer. Neovascularization after ischemic conditioning of the stomach before esophagectomy is a laparoscopic procedure which may potentially reduce gastric conduit ischemia. AIM: To investigate the influence of ischemic conditioning on neovascularization along the greater curvature of the stomach and to explore the effect of neoadjuvant chemotherapy on neovascularization after ischemic conditioning. MATERIAL AND METHODS: Staging laparoscopy was performed before the main resection procedure; during this procedure ischemic conditioning was performed. Samples taken from the human stomach were divided into 3 groups: group A - patients after ischemic conditioning with a delay of 30-45 days after left gastric artery (LGA) ligation (n = 4); group B - patients who were undergoing neoadjuvant chemotherapy with a delay of 90-140 days after left gastric artery ligation (n = 4); and control group C - patients without ischemic conditioning (n = 7). RESULTS: After ischemic conditioning with a delay of 30-45 days, the count of neovessels along the greater curvature of the stomach increased from 5.4 ±0.7 in the control group to 17.5 ±0.9 in a low-power field of view (LPF) in group A and increased still further on average to 19.8 ±10.4 in group B. CONCLUSIONS: Left gastric artery ligation only is a sufficient procedure for ischemic conditioning of the stomach. Neovascularization along the greater curvature is a continuous process that depends on delay time. Neoadjuvant therapy has no influence on the effect of neovascularization.

Comparison of two non-invasive methods of microbial analysis in surgery practice: incision swabbing and the indirect imprint technique.

BACKGROUND: A variety of methods exist to take samples from surgical site infections for cultivation; however, an unambiguous and suitable method has not yet been defined. The aim of our retrospective non-randomized study was to compare two non-invasive techniques of sampling material for microbiologic analysis in surgical practice. We compared bacteria cultured from samples obtained with the use of the swab technique, defined in our study as the gold standard, with the indirect imprint technique. METHODS: A cotton-tipped swab (Copan, Brescia, Italy) was used; the imprints were taken using Whatman no. 4 filter paper (Macherey-Nagal, Duren, Germany) cut into 5×5 cm pieces placed on blood agar in a Petri dish. To culture the microorganisms in the microbiology laboratory, we used blood agar, UriSelect 4 medium (Bio-Rad, Marnes-la-Coquette, France), and a medium with sodium chloride (blood agar with salt). After careful debridement, a sample was taken from the incision surface by swab and subsequently the same area of the surface was imprinted onto filter paper. The samples were analyzed in the microbiology laboratory under standard safety precautions. The cultivation results of the two techniques were processed statistically using contingency tables and the McNemar test. Those samples that were simultaneously cultivation-positive by imprint and -negative by swabbing were processed in greater detail. RESULTS: Over the period between October 2008 and March 2013, 177 samples from 70 patients were analyzed. Sampling was carried out from 42 males and 28 females. One hundred forty-six samples were from incisions after operations (21 samples from six patients after operation on the thoracic cavity, 73 samples from 35 patients after operation on the abdominal cavity combined with the gastrointestinal tract, 52 samples from 19 patients with other surgical site infections not included above) and 31 samples from 11 patients with no post-operative infection. One patient had a sample taken both from a post-operative and a non-post-operative site. Coincidently, the most frequent cultivation finding with both techniques was a sterile one (imprint, 62; swab, 50). The microorganism cultivated most frequently after swabbing was Pseudomonas aeruginosa (22 cases), compared with Escherichia coli when the filter paper (imprint) was used (31 cases). The imprint technique was evaluated as more sensitive compared with swabbing (p=0.0001). The κ statistic used to evaluate the concordance between the two techniques was 0.302. Of the 177 samples there were 53 samples simultaneously sterile using the swab and positive in the imprint. In three samples colony- forming units (CFU) were not counted; 22 samples were within the limit of 0-25×10(1) CFU/cm(2), 20 samples within the limit of 25×10(1)-25×10(2) CFU/cm(2), five within the limit of 25×10(2)-25×10(3) CFU/cm(2), and three of more than 25×10(4) CFU/cm(2). CONCLUSIONS: The hypothesis of swabbing as a more precise technique was not confirmed. In our study the imprint technique was more sensitive than swabbing; the strength of agreement was fair. We obtained information not only on the type of the microorganism cultured, but also on the number of viable colonies, expressed in CFU/cm(2).

Differential effects of insulin and dexamethasone on pulmonary surfactant-associated genes and proteins in A549 and H441 cells and lung tissue.

In this study, the effects of insulin and dexamethasone on the expression and mRNA transcription of 4 pulmonary surfactant-associated proteins [surfactant protein (SFTP)A, SFTPB, SFTPC and SFTPD] were examined. The commercially available cell lines, A549 and H441, were used as acceptable models of lung surfactant-producing cells. Subsequently, the effects of insulin on the expression of surfactant-associated proteins were examined in patients with lung adenocarcinoma during lung resection. Our results demonstrated the inhibitory effects of insulin on the transcription of the SFTPB, SFTPC and SFTPD genes in H441 cells and the SFTPB gene in A549 cells. Treatment with insulin significantly decreased the protein expression of SFTPA1 and SFTPA2 in the H441 cells and that of proSFTPB in the A549 cells. Dexamethasone promoted the transcription of the SFTPB, SFTPC and SFTPD genes in the A549 and H441 cells and reduced the transcription of the SFTPA1 and SFTPA2 genes in the H441 cells (SFTPA mRNA expression was not detected in A549 cells). Furthermore, we demonstrated that the mRNA levels of the selected genes were significantly lower in the cell lines compared to the lung tissue. A549 and H441 cells represent similar cell types. Yet, in our experiments, these cells reacted differently to insulin and/or dexamethasone treatment, and the mRNA levels of their main protein products, surfactant-associated proteins, were significantly lower than those in real tissue. Therefore, the results obtained in this study challenge the suitability of A549 and H441 cells as models of type II pneumocytes and Clara cells, respectively. However, we successfully demonstrate the possibility of studying the effects of insulin on pulmonary surfactant-associated genes and proteins in patients with lung adenocarcinoma.