Background & Aims: Bacterial infections commonly occur in decompensated cirrhosis resulting from bacterial translocation from the intestine. We studied the role of intestinal macrophages and the epithelial barrier in cirrhosis. Methods: Forty-four patients with NASH/ASH cirrhosis (decom-pensated n = 29, compensated n = 15) and nineteen controls undergoing endoscopy were recruited. Serum was obtained and LPS and LBP levels determined. Intestinal macrophages were characterized by flow cytometry, immunohistochemistry, and nitric oxide (NO) production measured in supernatant of cultured duodenal samples. Quantitative RT-PCR was performed on duo-denal biopsies assessing 84 inflammatory genes. Protein levels of cytokines/chemokines were assessed in serum and superna-tant. The duodenal wall was assessed by electron microscopy, tight junction protein expression determined by RT-PCR, immu-nohistochemistry, and Western blot and, functional analysis performed by transepithelial resistance measurement and per-meability studies. Results: Increased plasma LPS, LBP levels and higher numbers of duodenal CD33 + /CD14 + /Trem-1 + macrophages, synthesizing iNOS and secreting NO were present in decompensated cirrhosis. Upregulation of IL-8, CCL2, CCL13 at the transcriptional level, and increased IL-8, and IL-6 were detected in supernatant and serum in cirrhosis. IL-6 and IL-8 co-localised with iNOS + and CD68 + , but not with CD11c + cells. Electron microscopy demon-strated an intact epithelial barrier. Increased Claudin-2 was detected by Western blot and immunohistochemistry, while decreased transepithelial resistance and increased duodenal per-meability were detected in decompensated cirrhosis. Conclusions: Our study shows the presence of activated CD14 +-Trem-1 + iNOS + intestinal macrophages, releasing IL-6, NO, and increased intestinal permeability in patients with cirrhosis, sug-gesting that these cells may produce factors capable of enhancing permeability to bacterial products.

Uterine perivascular epithelioid cell tumors (PEComas) are rare neoplasms that may show overlapping morphology and immunohistochemistry with uterine smooth muscle tumors. In this study, we evaluated the morphologic, immunohistochemical, and molecular features of 32 PEComas, including 11 with aggressive behavior. Two distinct morphologies were observed: classic (n=30) and those with a lymphangioleiomyomatosis appearance (n=2). In the former, patients ranged from 32 to 77 (mean: 51) years and 13% had tuberous sclerosis. Tumors ranged from 0.2 to 17 (mean: 5.5) cm with 77% arising in the corpus. Epithelioid cells were present in 100% and a spindled component was seen in 37%. Nuclear atypia was low (53%), intermediate (17%), or high (30%). Mitoses ranged from 0 to 36 (mean: 6) and 0 to 133 (mean: 19) per 10 and 50 high-power fields, with atypical mitoses present in 30%. Thin and delicate vessels were noted in 100%, clear/eosinophilic and granular cytoplasm in 93%, stromal hyalinization in 73%, necrosis in 30%, and lymphovascular invasion in 10%. All tumors were positive for HMB-45, cathepsin K, and at least one muscle marker, with most expressing melan-A (77%) and/or MiTF (79%). A PSF-TFE3 fusion was identified in one while another showed a RAD51B-OPHN1 fusion. Follow-up ranged from 2 to 175 (mean: 41) months, with 63% of patients alive and well, 20% dead of disease, 13% alive with disease, and 3% dead from other causes. In the latter group (n=2), patients were 39 and 49 years old, one had tuberous sclerosis, while the other had pulmonary lymphangioleiomyomatosis. Both tumors expressed HMB-45, cathepsin K, and muscle markers, but lacked TFE3 and RAD51B rearrangements. The 2 patients are currently alive and well. Application of gynecologic-specific criteria (≥4 features required for malignancy: size ≥5 cm, high-grade atypia, mitoses >1/50 high-power fields, necrosis, and lymphovascular invasion) for predicting outcome misclassified 36% (4/11) of aggressive tumors; thus, a modified algorithm with a threshold of 3 of these features is recommended to classify a PEComa as malignant.

Dimers, trimers, and tetramers of bovine ribonuclease A, obtained by lyophilization of the enzyme from 40% acetic acid solutions, were purified and isolated by cation exchange chromatography. The two conformers constituting each aggregated species were assayed for their antitumor, aspermatogenic, or embryotoxic activities in comparison with monomeric RNase A and bovine seminal RNase, which is dimeric in nature. The antitumor action was tested in vitro on ML-2 (human myeloid leukemia) and HL-60 (human myeloid cell line) cells and in vivo on the growth of human non-pigmented melanoma (line UB900518) transplanted subcutaneously in nude mice. RNase A oligomers display a definite antitumor activity that increases as a function of the size of the oligomers. On ML-2 and HL-60 cells, dimers and trimers generally show a lower activity than bovine seminal RNase; the activity of tetramers, instead, is similar to or higher than that of the seminal enzyme. The growth of human melanoma in nude mice is inhibited by RNase A oligomers in the order dimers < trimers < tetramers. The action of the two tetramers is very strong, blocking almost completely the growth of melanoma. RNase A dimers, trimers, and tetramers display aspermatogenic effects similar to those of bovine seminal RNase, but, contrarily, they do not show any embryotoxic activity.Bovine ribonuclease A oligomerizes in the forms of dimers (1), trimers, tetramers, and higher order oligomers (2) during lyophilization from 40% acetic acid solutions. Each oligomer consists of two conformational isomers, which can be separated by cation exchange chromatography into a less basic and a more basic species (2, 3). The molecular structures of the two dimers have been solved (4, 5). They form by a three-dimensional domain-swapping mechanism (6); the less basic dimer, formerly named minor because of its ratio of 1:4 to the more basic dimer (2,3,5), is formed by the swapping of the Nterminal ␣-helix (residues 1-15) of each monomeric subunit, and the more basic or major dimer (2, 3, 5) is formed by the swapping of the C-terminal ␤-strand (residues 116 -124) of each monomer. On this basis, the two dimers will be called N-dimer and C-dimer, respectively. The structure of the more basic or minor trimer (2, 3) has also been solved; it is formed by three monomers linked to each other by swapping their Cterminal ␤-strands, thereby forming a circular structure that looks like a propeller (7). It will be called the C-trimer in this paper. On the basis of its dissociation products (3, 7), a plausible linear model was proposed for the less basic, major trimer (its abundance is 1.5 times that of the more basic, minor trimer). In this linear model, two monomers are linked through swapping of their N termini, and a third monomer is bound to one of them by C-terminal domain swapping (5, 7). It will be called the NC-trimer. Two linear structures for the two tetramers, the less basic minor and the more basic major (ratio, 1:1.6), have also been proposed on the basis of their dissociation products (...

Cronkhite–Canada syndrome is a rare gastro-entero-colopathy of uncertain aetiology first described almost 60 years ago. It is characterised by diffuse gastrointestinal polyposis sparing only the oesophagus, ectodermal abnormalities and an unpredictable but often fatal clinical course. The disease may demonstrate extremely diverse clinical and endoscopic features, which often leads to a delay in diagnosis. A high index of suspicion and recognition of the characteristic histological findings frequently facilitate a correct diagnosis, but the distribution of the gastrointestinal pathology and its microscopic features may be atypical. The pathologist thus requires a thorough knowledge of both the typical and many atypical faces of this disease, for which various documented therapies often still prove ineffective. Close correlation with clinical findings, including any pertinent ectodermal abnormalities, and careful examination of biopsies derived from polypoid and endoscopically spared mucosa will ensure a timely and correct diagnosis in patients with this enigmatic syndrome.

Our study aimed to evaluate the oral cavity as a reservoir from where Helicobacter pylori may be transmitted. Histology and PCR amplification were performed. Eighty-four percent of the stomach biopsies tested positive; however, H. pylori was not detected in dental samples, indicating the absence of H. pylori within the oral cavity.It has been suggested that the oral cavity may play a role in the transmission of Helicobacter pylori. Increased H. pylori prevalence rates have been reported in Chinese immigrants who use chopsticks and in African infants whose mothers premasticate their food (4, 16). H. pylori has been detected in dental plaque and saliva by culture and PCR methods, with the results obtained ranging from 0 to 100% for culture and 0 to 90% for PCR (1-3, 5, 7, 9, 11, 12, 14, 15, 17, 18, 20, 21). The role of the oral cavity as a permanent reservoir for H. pylori infection in healthy nonhospitalized individuals is still unclear (6, 10).Seventy-nine (25 men and 54 women; mean age, 27 years; range, 5 to 65 years) healthy individuals from a rural community in South Africa were included in this study. We previously showed that this community had a high H. pylori seroprevalence rate (23,24). The ethics committee of the University of Pretoria and the Review Board of Unitas Hospital approved this study.Cumulative dental plaque samples were obtained from the oral cavity, and biopsies were taken from two sites in the stomach (two from the antrum and two from the corpus). One biopsy specimen from each site was placed in 10% formalin, cut, and stained with hematoxylin-eosin and methylene blue. DNA was extracted from the remainder of the samples by using the QIAamp DNA Mini kit (QIAGEN, Hilden, Germany) per the manufacturer's instructions and stored at Ϫ20°C. The quality and concentration of the extracted DNA was assessed by means of a Nanodrop Spectrophotometer (A 260 /A 280 , 1.6 to 2.00).A single-step PCR directed toward the urease AB gene and a heminested PCR directed toward the phosphoglucosamine mutase (glmM) gene of H. pylori were performed on dental plaque and biopsy samples (8). A third nested PCR directed toward the 860-bp DNA region of H. pylori was performed on dental plaque samples (21,22). Negative and positive controls (H. pylori type strain Hp115.90) were included in each batch of amplifications. Amplification was performed on the GeneAmp 9700 thermocycler (Applied Biosystems, Foster City, Calif.). To exclude the possibility of PCR amplifications being negative due to the presence of inhibitors, the single-step PCR amplifying the urease AB gene was repeated for dental plaque samples spiked with DNA isolated from the positive control.The sensitivities, specificities, and percentages of infected individuals are represented in Table 1. Sensitivity and specificity were calculated compared to the gold standard of histology. Dental plaque samples were not collected for five individuals, and biopsy samples were not collected for one individual included in the study. Five samples were excluded due to the fac...