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Essentials Tissue factor (TF) isoforms are expressed in pancreatic neuroendocrine tumors (pNET). TF knockdown inhibits proliferation of human pNET cells in vitro. mTOR kinase inhibitor sapanisertib/MLN0128 suppresses TF expression in human pNET cells. Sapanisertib suppresses TF expression and activity and reduces the growth of pNET tumors in vivo. SUMMARY: Background Full-length tissue factor (flTF) and alternatively spliced TF (asTF) contribute to growth and spread of pancreatic ductal adenocarcinoma. It is unknown, however, if flTF and/or asTF contribute to the pathobiology of pancreatic neuroendocrine tumors (pNETs). Objective To assess TF expression in pNETs and the effects of mTOR complex 1/2 (mTORC1/2) inhibition on pNET growth. Methods Human pNET specimens were immunostained for TF. Human pNET cell lines QGP1 and BON were evaluated for TF expression and responsiveness to mTOR inhibition. shRNA were used to knock down TF in BON. TF cofactor activity was assessed using a two-step FXa generation assay. TF promoter activity was assessed using transient transfection of human TF promoter-driven reporter constructs into cells. Mice bearing orthotopic BON tumors were treated with the mTORC1/2 ATP site competitive inhibitor sapanisertib/MLN0128 (3 mg kg -1 , oral gavage) for 34 days. Results Immunostaining of pNET tissue revealed flTF and asTF expression. BON and QGP1 expressed both TF isoforms, with BON exhibiting higher levels. shRNA directed against TF suppressed BON proliferation in vitro. Treatment of BON with sapanisertib inhibited mTOR signaling and suppressed TF levels. BON tumors grown in mice treated with sapanisertib had significantly less TF protein and cofactor activity, and were smaller compared with tumors grown in control mice. Conclusions TF isoforms are expressed in pNETs. Sapanisertib suppresses TF mRNA and protein expression as well as TF cofactor activity in vitro and in vivo. Thus, further studies are warranted to evaluate the clinical utility of TF-suppressing mTORC1/2 inhibitor sapanisertib in pNET management., (© 2018 International Society on Thrombosis and Haemostasis.)

Objective: To find out if clearance of surgical colectomy specimens with xylene gave a higher yield of lymph nodes and more accurate staging than the traditional step-sectioning technique., Design: Consecutive open study., Setting: Private hospital, United States., Material: 84 specimens from colonic resections, 4 of which were total colectomies and the remaining 80 segmental resections., Interventions: The first 41 (2 colectomies and 39 segmental resections) were cleared by step-sectioning alone (to establish baseline values). The remainder (n = 2 and 41, respectively) were step-sectioned, the lymph nodes were removed, and then the residual tissue was cleared with xylene., Main Outcome Measures: The number of lymph nodes found, and if the diagnosis was changed by the finding of additional nodes., Results: The baseline values in the two total colectomy specimens were 76 and 101, and the mean (range) after segmental colectomy was 21 (1-98). The values after total colectomy in the second group were 33 and 73, and after xylene clearance an additional 12 and 17 nodes were found. After segmental colectomy a mean (range) of 13 (0-43) was found, and an additional 4 (0-12) were found after xylene clearance. No additional nodes containing metastases were found in total colectomy specimens after xylene clearance, and only 6 additional nodes after segmental resection contained metastases. These changed the histological stage of the disease in only 2 patients., Conclusions: Xylene clearance offers little advantage over careful traditional step-sectioning of specimens, but may be of value if the histopathologist does not do routine meticulous step-sectioning.

Ischemic colitis with colonic necrosis is one of the uncommon gastrointestinal complications of systemic lupus erythematosus. In the few reported cases, only the abdominal part of the colon was involved with rectal sparing. This is the first report of gangrenous ischemic colitis isolated to the rectum, due to systemic lupus erythematosus vasculitis.

A study was undertaken to assess the incidence of inflammation and dysplasia in retained mucosa after double-stapled ileoanal reservoir (IAR) for mucosal ulcerative colitis (MUC). Between September 1988 and February 1992, 56 patients with MUC underwent an IAR. Forty-five patients had a double-stapled IAR (DS-IAR), seven patients had a transanal pursestring stapled IAR (PS-IAR), and four patients had a PS-IAR with mucosectomy. Distal donuts obtained from the stapled IAR were submitted for pathologic review in 55 patients. Nine patients had only small bowel, connective tissue, and/or muscle noted on review. Mucosa was qualified as squamous epithelium (SE), transitional epithelium (TE), or columnar epithelium (CE). All samples were examined for evidence of inflammation and dysplasia. Four patients had SE only, one patient had TE, and 18 had CE. In addition, three patients had SE and CE, seven patients had SE and TE, two patients had CE and TE, and nine patients had all three types. The distance from the dentate line to the anastomosis ranged from 0 to 2.5 cm (mean, 1 cm). In 19 patients (35 percent), the distal donut revealed MUC. Of these 19 patients, six had persistent MUC (43 percent) at the time of subsequent biopsy. An additional four patients had MUC evident on follow-up biopsy but not on distal donuts; two of these four patients had no mucosa in their distal donuts. Only one of the patients with evidence of MUC on donuts and/or biopsy experienced any symptoms referable to active MUC (1.8 percent). None of the specimens examined had any evidence of dysplasia. In 31 patients, no MUC was present in the initial donuts or follow-up biopsies. Although the double-stapled technique appears safe, periodic monitoring is suggested.

Of 40 patients with thrombotic thrombocytopenic purpura, 17 were treated with plasma exchange, 15 with exchange transfusions, and 6 with both types of therapy. One patient died before being treated and another patient was seen but not treated. Plasma exchange was performed daily for a mean of seven exchanges per patient. The replacement fluid during plasma exchange was fresh frozen plasma in all cases. The complete response rates for each type of treatment were as follows: 88% for plasma exchange (15 patients), 47% for exchange transfusions (7 patients), and 67% for exchange transfusions and plasma exchange (4 patients). Clinical and laboratory factors were examined for any statistically significant association with therapy response. Treatment with plasma exchange was statistically the initial factor most strongly associated with prognosis. Paresis, paresthesias, seizures, mental status change, and coma showed no association with response to treatment. Some of the laboratory factors that did not show significant association with treatment response were the initial creatinine, hemoglobin, platelet count, lactate dehydrogenase, and total bilirubin. This study supports the hypothesis that plasma exchange has significantly improved the prognosis of patients with thrombotic thrombocytopenic purpura. These patients should be treated aggressively regardless of the severity of their symptoms.

Cross-linked fibrin(ogen) dimers are known to be elevated in the plasma of subjects with occlusive vascular disease, and are thought to be fibrin dimers. Immunoelectrophoretic analyses of the dimers, however, indicate that (1) they are predominantly fibrinogen rather than fibrin dimers, and (2) they contain cross-linked A alpha-chains (A alpha-dyads) instead of the gamma-chain dyads that are rapidly formed by factor XIII during blood coagulation. Furthermore, the mobilities of the A alpha-dyads differ from the cross-linked alpha-chain products that accompany the gamma-chain cross-linking by factor XIII. Instead, the mobilities coincide with the distinct A alpha-dyads that are produced by tissue transglutaminase, an intracellular enzyme not normally present in plasma. The intimal fibrinogen deposits in atherosclerotic aortas also possess fibrinopeptide A and cross-linked A alpha-chains. Thus, both the plasma fibrinogen dimers and the intimal fibrinogen deposits appear to derive from the action of released tissue transglutaminase more so than factor XIII. It is proposed that, in the absence of other indications of cytolytic processes, the levels of A alpha-dyads in plasma reflect ongoing cellular injury accompanying atherogenesis. The extent to which gamma-dyads accompany the A alpha-dyads may signal progression of the disease to advanced stages in which ulcerations and occlusive lesions trigger thrombotic complications.

An ability of intravenous nitroglycerin to interfere with the anticoagulant properties of intravenous heparin would have profound clinical implications. To investigation nitroglycerin-heparin interactions, the following pilot study was performed. Patients (N = 18) admitted to the coronary care unit with a diagnosis of either acute myocardial infarction or unstable angina were divided into four treatment groups: (1) intravenous nitroglycerin and intravenous heparin; (2) intravenous nitroglycerin alone; (3) intravenous heparin alone; or (4) neither intravenous nitroglycerin nor intravenous heparin. Serial determinations of activated partial thromboplastin time (APTT), serum heparin concentration, antithrombin III (ATIII) antigen (ATA), and ATIII activity (ATC) were obtained over a 72-hour period. Overall, patients receiving intravenous nitroglycerin did not differ significantly from other patients in APTT, heparin dose, heparin concentration, ATA, ATC, or ATA/ATC ratio (ATR). However, patients receiving intravenous nitroglycerin at a rate exceeding 350 micrograms per minute had a lower APTT (p less than 0.05), lower ATC (p = 0.02), higher ATR (p = 0.004), and a larger heparin dose requirement than patients receiving lower infusion rates. ATR correlated directly (r = 0.91; p less than 0.05) and ATC inversely (r = -0.78; p less than 0.05) with the intravenous nitroglycerin dose. Serum heparin concentration did not correlate with the intravenous nitroglycerin dose. Intravenous nitroglycerin-induced heparin resistance occurs at a critical nitroglycerin dose. A nitroglycerin-induced qualitative ATIII abnormality may be the underlying mechanism.

Myeloperoxidase staining methods for classification of leukemias have traditionally employed benzidine dihydrochloride as the chromogen. Recent Occupational Safety and Health Administration regulations have classified benzidine as a carcinogen, which severely restricts its use in the clinical laboratory. Twenty-two specimens from normal control subjects and leukemia patients, previously classified by FAB criteria, were stained with benzidine and two alternate chromogens, diaminobenzidine and Hanker-Yates reagent (p-phenylenediamine and pyrocatechol). In a random, blind fashion, three experienced observers scored the stains from each case according to quality of smear, degree of peroxidase positivity, tinctorial distinction between nucleus and cytoplasm, and overall acceptability of the stain. All three observers rated the substitute chromogens as adequate for routine myeloperoxidase cytochemical staining. It is concluded that either of the methods studied would have clinical utility and can substitute for benzidine as a myeloperoxidase chromogen.

Fifty-eight patients with clinical inflammatory breast carcinoma and 15 patients with "occult" inflammatory cancer (dermal lymphatic carcinomatosis without clinical inflammation) are grouped and reviewed to determine whether diagnosis is pathologic or clinical. All cases represent a retrospective study of records from the Ellis Fischel State Cancer Hospital, Columbia, Missouri. Lesions of clinically apparent and occult inflammatory carcinoma demonstrate similar gross and microscopic growth patterns, histologic types, axillary involvement and early widespread metastases. Regardless of pathologic evidence of dermal lymphatic tumor, patients with clinical inflammation had rapid deterioration. Cases with only a pathological diagnosis were slightly less fulminant in progression. Either clinical or pathologic criteria justify use of the term "inflammatory breast carcinoma" to indicate short-term prognosis despite available treatment.

Electron-microscope study of chick tendon fibroblast revealed a constant ultrastructural finding of a microtubular-microfibrillar system and an intimate relationship which existed between the microtubular-microfibrillar system and secretory vacuoles. Additionally, the data from this study suggest a mechanism by which newly synthesized collagen molecules are transported and secreted into the extracellular space to be organized into mature collagen.

A new assay for IgG bound to autologous platelets is described, in which IgG is dissociated from platelets washed at low pH, then measured by radioimmunoassay. Platelet-bound IgG was found to be elevated in thrombocytopenic patients with SLE and reduced in non-thrombocytopenic patients with this disease. There was a close inverse correlation of platelet-bound IgG and platelet count. Immune complexes did not interfere with the assay.

Twenty-two patients were selected from a group of 33 patients who underwent recombinant human tissue-type plasminogen activator (rt-PA) thrombolysis for thrombosed infrainguinal bypass grafts of the lower extremity and were compared with 38 matched patients who had undergone surgical thrombectomy during the same period. The proportion of persons with diabetes mellitus, smokers, and types of bypass grafts was similar in both groups. More patients in the rt-PA-treated group had hypertension (p = 0.01). To evaluate the different lengths of follow-up, Kaplan-Meier survival analysis was used with a log-rank test to compare the proportion of persons with patent grafts in the two treatment groups. At 30 days, 86% of the rt-PA-treated grafts were still patent compared with 42% of the surgically treated grafts (p = 0.001). When risk factors on the Kaplan-Meier curves were compared, there was no statistical difference with regard to graft patency among the groups. According to simultaneous Cox regression analysis, no risk factor was significantly associated with graft patency. When amputation was evaluated between treatment groups simultaneously with other risk factors in a logistic regression analysis, smoking and age of the graft were marginally significant (p = 0.07), whereas all other factors were clearly not significant. In 91% of the rt-PA-treated patients, a secondary surgical procedure was required to maintain patency of the graft segment. Eighty-nine percent of the surgically treated patients required similar graft revisions. Two patients in the surgical group and one patient in the rt-PA-treated group had major complications.(ABSTRACT TRUNCATED AT 250 WORDS)

Factor VIII assays are the most common specific coagulation factor assay performed in the United States. Interlaboratory proficiency studies have documented persistent problems with variation in results between laboratories. The Coagulation Resource Committee of the College of American Pathologists conducted a workshop to analyze variables that may affect performance of the one-stage factor assay. The results indicate that accuracy of the assay can be improved by uniform standardization of reference plasma samples and that reproducibility can be enhanced through appropriate choice of reagents and instruments. Optimizing performance of this assay should lead to more reproducible interlaboratory results.

Thirty-three patients with thrombosed peripheral arteries and bypass grafts, as confirmed by angiography, were treated with recombinant human tissue-type plasminogen activator (rt-PA). Twenty-six patients were treated with a dose of 0.1 mg/kg/hr and seven patients with 0.05 mg/kg/hr. Thrombus lysis and clinical improvement occurred in 22 of 26 (85%) patients in the 0.1 mg/kg/hr group. In seven of seven (100%) patients in the 0.05 mg/kg/hr group angiographic as well as clinical improvement were observed. Fifteen of the 33 patients required anticoagulation to maintain patency. Sixteen required secondary procedures to maintain patency. One (3%) patient required a blood transfusion for a hematoma at the catheter entry site. Three other patients developed small hematomas that were controlled without transfusion or intervention. Sixty-one percent of patients treated with the 0.01 mg/kg/hr dose and 86% of patients treated with the 0.05 mg/kg/hr dose maintained fibrinogen levels greater than 50% of their initial values. Infusion durations ranged from 1 to 6 hr (mean 3.9 hr). rt-PA appears to be a potent and selective thrombolytic agent that rapidly and safely lyses thrombi in peripheral arteries and occluded bypass grafts.

Fluorescein is a reliable indicator of mucosal viability in dogs. This fact is probably applicable to humans. The Doppler device was not a reliable predictor of intestinal nonviability, and in the instance of mesenteric venous occlusion, with ischemic intestine, it was totally inaccurate in assessing intestinal viability. Short segments of intestine failing to take up fluorescein stain will retain viability, owing to the lesser nutrient requirements of resting smooth muscle. However, segments should not be used for anastomoses, since the mucosa will, to some degree be ischemic.