Liver Transplantation Trends and Outcomes for Hereditary Hemorrhagic Telangiectasia in the United States.

BACKGROUND: Liver arteriovenous malformations (AVM) in hereditary hemorrhagic telangiectasia (HHT) can necessitate liver transplantation. There is limited data on HHT patients undergoing liver transplantation (LT) in the United States. METHODS: Two sources of data were used: (1) Scientific Registry of Transplant Recipients (SRTR) database (1998-2016) (2) Single center liver transplant database (Mayo Clinic Rochester, MN). The aims of this study were (1) to determine trends in LT for HHT-related liver involvement in the United States using the SRTR database; (2) to identify clinical characteristics, indications, and outcomes for LT in HHT. RESULTS: Thirty-nine HHT patients were listed for LT in the SRTR database from 1998-2016 to 1998-2001 (n = 1); 2002-2005 (n = 4); 2006-2010 (n = 10), and 2011-2016 (n = 24). Twenty-four underwent LT at a median age of 47.5 years (interquartile range, 37.0-58.5 years). Median calculated MELD score at time of LT was 8.0 (interquartile range, 7.0-9.5), and 75% received an exception MELD score. Two status-1 patients died during transplant surgery. Nineteen (86%) patients were alive after a median post-LT follow-up of 48 months, whereas 2 patients were lost to follow-up. Five of the aforementioned HHT patients underwent LT at Mayo Clinic, 4 with high output cardiac failure, and 1 with biliary ischemia. All 5 were alive at the time of last follow-up with good graft function and resolution of heart failure. CONCLUSIONS: Outcomes after LT for HHT patients are excellent with 86% survival after a median follow-up of 48 months and resolution of heart failure. LT listing for HHT has increased in substantially in more recent eras.

Feasibility and outcomes of percutaneous thermal ablation of hepatocellular carcinoma in a transplanted allograft.

PURPOSE: To examine the safety, feasibility, and oncologic control following percutaneous image-guided thermal ablation of hepatocellular carcinoma (HCC) in a transplanted allograft. MATERIALS AND METHODS: Retrospective review was performed to identify patients who underwent liver transplantation for HCC and subsequently underwent percutaneous hepatic thermal ablation for recurrent HCC within the allograft between January 1st, 2000-September 1st, 2016. Eleven patients with hepatic allograft HCC underwent twelve percutaneous thermal ablation procedures to treat 16 lesions. Patient, procedural characteristics, and local oncologic efficacy were reviewed. Complications were characterized via the Common Terminology for Clinically Adverse Events nomenclature [CTCAE] v4.03). RESULTS: Eleven transplant recipients underwent treatment of 16 HCC tumors in their allografts during 12 ablation sessions. Mean follow-up time was 25 months (range 2-96 months). Local oncologic control was achieved in 10 of 11 tumors (91%) with imaging follow-up. One patient (8%) with Roux-en-Y biliary reconstruction developed a major complication with hepatic abscess. CONCLUSION: Thermal ablation of recurrent HCC in transplanted allografts can be accomplished safely with acceptable rates of local control for patients with duct-to-duct biliary reconstruction. Due to the high number of patients deemed surgically unresectable, the morbidity of surgical resection, the side effects of targeted therapies, and significant mortality associated with recurrences in the transplanted allograft, patients may benefit from percutaneous thermal ablative treatments. Further study is needed to assess the role of thermal ablation in allograft HCC recurrences as primary therapy or in a multimodality approach with emerging systemic therapies.

Internal hernia and small bowel obstruction following open ileoanal pouch formation: A case report.

INTRODUCTION: Internal herniae, although rare, can give rise to potentially serious morbidity and mortality. The protrusion and entrapment of the small bowel through an embryological or iatrogenic mesenteric aperture within the confines of the peritoneal cavity can be difficult to diagnose, and delay treatment (operative). Timely intervention must be achieved to minimize small bowel ischemia and infarction. CASE PRESENTATION: In this case, a young lady who had a previous laparoscopic total colectomy and ileostomy developed an unusual internal hernia. Small bowel was passing behind the lesser curvature of the stomach causing the stomach to be rotated to form of a tight "band" trapping bowel. The herniated small bowel was reduced, hence, avoiding resection; the defect closed by interupted 4-0 PDS. "Prompt" surgery avoided small bowel length resection and sacrifice of the ileoanal pouch reconstruction. DISCUSSION: It is theorized that a laparoscopic approach results in a more advanced mobilization of the mesentery right up to the small bowel origin, and with less adhesion formation may in fact promote unusual internal hernia and volvulus. CONCLUSION: The case presented highlights the difficulty in making the diagnosis, and the pictures clearly indicate an unusual hernia passing directly behind the stomach and involving a large section of the small bowel. The lead up history of several admissions with sub acute small bowel obstruction suggested the underlying problem was adhesional but quite clearly there was a well defined internal hernia. Without timely surgery she would have been at high risk of losing her pouch.

CIP4 promotes lung adenocarcinoma metastasis and is associated with poor prognosis.

Aberrant epidermal growth factor receptor (EGFR) signaling in non-small cell lung cancer (NSCLC) is linked to tumor progression, metastasis and poor survival rates. Here we report the role of Cdc42-interacting protein 4 (CIP4) in the regulation of NSCLC cell invasiveness and tumor metastasis. CIP4 was highly expressed in a panel of NSCLC cell lines and normal lung epithelial cell lines. Stable knockdown (KD) of CIP4 in lung adenocarcinoma H1299 cells, expressing wild-type EGFR, led to increased EGFR levels on the cell surface and defects in sustained activation of Erk kinase in H1299 cells treated with EGF. CIP4 localized to leading edge projections in NSCLC cells, and CIP4 KD cells displayed defects in EGF-induced cell motility and invasion through extracellular matrix. This correlated with reduced expression and activity of matrix metalloproteinase-2 (MMP-2) in CIP4 KD cells compared with control. In xenograft assays, CIP4 silencing had no effect on tumor growth but resulted in significant defects in spontaneous metastases to the lungs from these subcutaneous tumors. This correlated with reduced expression of the Erk target gene Zeb1 and the Zeb1 target gene MMP-2 in CIP4 KD tumors compared with control. CIP4 also enhanced rates of metastasis to the liver and lungs in an intrasplenic experimental metastasis model. In human NSCLC tumor sections, CIP4 expression was elevated greater than or equal to twofold in 43% of adenocarcinomas and 32% of squamous carcinomas compared with adjacent normal lung tissues. Analysis of microarray data for NSCLC patients also revealed that high CIP4 transcript levels correlated with reduced overall survival. Together, these results identify CIP4 as a positive regulator of NSCLC metastasis and a potential poor prognostic biomarker in lung adenocarcinoma.

Recurrence of hepatocellular carcinoma: importance of mRECIST response to chemoembolization and tumor size.

Determining risk for recurrence of hepatocellular carcinoma (HCC) following liver transplantation (LT) is an important clinical need. We assessed consecutive patients who underwent LT for HCC following sequential transarterial chemoembolization (TACE). Treatment response was assessed using modified response evaluation criteria in solid tumors (mRECIST) categories: complete response (CR), partial response (PR), stable disease (SD) and progressive disease (PD). Cox proportional hazard models were used to predict HCC recurrence. One hundred seventy-three patients underwent TACE and imaging to assess response prior to LT. TACE responses were: CR = 23.7%, PR = 24.3%, SD = 27.7% and PD = 24.3%. Five-year HCC recurrence rate was 5.3% in patients responding to TACE (CR/PR), versus 17.6%, among patients who did not respond (SD/PD, p = 0.014). In multivariate analysis, independent pre-LT predictors of recurrence were response to TACE and largest radiologic size of tumor (>3 cm vs. ≤3 cm). HCC recurrence rate for patients with tumor size >3 cm and no response to TACE was 35.8%, compared with 1.9% for patients with tumor size ≤3 cm and response to TACE (p = 0.0007). We conclude that mRECIST criteria and tumor size differentiate patients with high or low likelihood of HCC recurrence after LT. These findings raise the possibility of incorporating response to TACE and largest tumor size to identify patients at highest risk for HCC recurrence.

Interactions of allelic variance of PNPLA3 with nongenetic factors in predicting nonalcoholic steatohepatitis and nonhepatic complications of severe obesity.

OBJECTIVE: Allelic variation (rs738409C→G) in adiponutrin (patatin-like phospholipase domain-containing protein 3, PNPLA3) has been associated with hepatic steatosis and liver fibrosis. The physiologic impact of the PNPLA3 G allele may be exacerbated in patients with severe obesity. In this study, we investigated the interactions of PNPLA3 rs738409 with a broad panel of metabolic and histologic characteristics of nonalcoholic fatty liver disease and nonalcoholic steatohepatitis (NASH) in patients with medically complicated obesity. DESIGN AND METHODS: Consecutive patients undergoing bariatric surgery were selected for a prospective study. They underwent extensive laboratory and histologic (liver biopsy) assessment, as well as evaluation of rs738409 polymorphism by TaqMan assay. RESULTS: Only 12 (8.3%) of the 144 patients had normal liver histology, with 72 (50%) NASH, of whom 15 (10.4% of total patients) had fibrosis stage 2-3. PNPLA3 GG genotype correlated positively (P < 0.05) with serum levels of alanine aminotransferase (ALT), asparate aminotransferase (AST), glucose, fibrinogen, and insulin-dependent diabetes mellitus, homeostasis model assessment-insulin resistance, and presence of NASH. Multivariate analysis indicated that PNPLA3 rs738409 G versus C allele remained an (independent) risk factor for NASH, in addition to CK-18 >145 IU/l, glucose >100 mg/dl, and C-reactive protein (CRP) >0.8 mg/dl. The probability of NASH increased from 9% (no risk factor) to 82% if all four risk factors were present. CONCLUSIONS: In this cohort of patients with medically complicated obesity, PNPLA3 rs738409 G allelic expression is associated with hepatic (NASH) and nonhepatic complications of obesity, such as insulin resistance. These novel findings may be related to a greater impact of PNPLA3 variant in magnitude and scope in patients with severe obesity than in less obese populations. Further studies are needed to characterize the nature of these associations.

Evolution of causes and risk factors for mortality post-liver transplant: results of the NIDDK long-term follow-up study.

Although mortality rates following liver transplantation (LT) are well described, there is a lack of detailed, prospective studies determining patterns of and risk factors for long-term mortality. We analyzed the multicenter, prospectively obtained The National Institute of Diabetes and Digestive and Kidney Diseases LT Database of 798 transplant recipients from 1990 to 1994 (follow-up 2003). Overall, 327 recipients died. Causes of death >1 year: 28% hepatic, 22% malignancy, 11% cardiovascular, 9% infection, 6% renal failure. Renal-related death increased dramatically over time. Risk factors for death >1 year (univariate): male gender, age/decade, pre-LT diabetes, post-LT diabetes, post-LT hypertension, post-LT renal insufficiency, retransplantation >1 year, pre-LT malignancy, alcoholic disease (ALD) and metabolic liver disease, with similar risks noted for death >5 years. Hepatitis C, retransplantation, post-LT diabetes, hypertension and renal insufficiency were significant risk factors for liver-related death. Cardiac deaths associated with age, male gender, ALD, cryptogenic disease, pre-LT hypertension and post-LT renal insufficiency. In summary, the leading causes of late deaths after transplant were graft failure, malignancy, cardiovascular disease and renal failure. Older age, diabetes and renal insufficiency identified patients at highest risk of poor survival overall. Diligent management of modifiable post-LT factors including diabetes, hypertension and renal insufficiency may impact long-term mortality.

Impact of pegylated interferon and ribavirin treatment on graft survival in liver transplant patients with recurrent hepatitis C infection.

Recurrent hepatitis C virus (HCV) infection is a major cause of morbidity and mortality after liver transplantation for HCV-related end stage liver disease. Although previous studies have shown a short-term effect of interferon-based treatment on fibrosis progression, it is unclear whether this translates to improved graft survival. We evaluated whether treatment of recurrent HCV leads to an improved graft survival. Cohort study included consecutive HCV patients who underwent liver transplantation between 1 January 1995 and 1 January 2005 in the Mayo Clinic, Rochester, MN. Two hundred and fifteen patients were included in the study. During a median follow-up of 4.4 years (interquartile range 2.2-6.6), 165 patients (77%) had biopsy-proven recurrent HCV infection confirmed by serum HCV RNA testing. Seventy-eight patients were treated. There were no differences in MELD-score, fibrosis stage or time towards HCV recurrence between treated and untreated patients at time of recurrence. There was a trend for greater frequency of acute cellular rejection among untreated patients. The incidence of graft failure was lower for patients treated within 6 months of recurrence compared to patients not treated within this time-period (log rank p = 0.002). Time-dependent multivariate Cox regression analysis showed that treatment of recurrent HCV infection was statistically significantly associated with a decreased risk of overall graft failure (hazard ratio 0.34; CI 0.15-0.77, p = 0.009) and a decreased risk of graft failure due to recurrent HCV (hazard ratio 0.24; CI 0.08-0.69, p = 0.008). In conclusion, although a cause and effect relationship cannot be established, treatment of recurrent HCV infection after liver transplantation is associated with a reduced risk of graft failure.

Lack of susceptibility to ischemic necrosis of the remnant liver following partial hepatectomy in the rat.

BACKGROUND/AIMS: The increase in liver lobule dimensions that occurs following partial hepatectomy could predispose living related donors to ischemic hepatic injury were shock-like states to occur in the future. METHODOLOGY: In the present study, rats that had undergone 70% partial hepatectomies or sham surgery six weeks earlier were progressively bled to a maximum of 40% total circulating blood volume. RESULTS: Despite significant increases in liver lobule dimensions (1.5x controls), hepatectomized rats did not manifest biochemical or histologic evidence of early or more extensive hepatic injury when compared to sham-operated controls. CONCLUSIONS: The results of this study suggest that despite theoretical concerns, living related donors are not predisposed to develop ischemic hepatic injury were shock-like states to develop in the future.

Growth performance and ileal and total tract amino acid digestibility in broiler chickens fed diets containing bacterial protein produced on natural gas.

A total of 180 broiler chickens were fed 1 of 3 diets from day-old to slaughter at 35 d: a control diet with 35% soybean meal (SOY) or diets in which either 6% basic bacterial protein meal (BBP) or 6% autolysed bacterial protein meal (AUT) partially replaced soybean meal protein. Ileal and total tract apparent amino acid digestibility were examined in 5 chickens per diet using TiO(2) as an inert marker. Chickens fed the diets with bacterial protein had higher weight gain and feed consumption than control chicks during the first 3 wk, but there were no differences in growth or feed intake during the last 2 wk or during the total experimental period. The birds fed the BBP diet showed more efficient feed conversion compared with chickens fed the SOY and AUT diets. Litter quality at 5 wk was poorer in pens where the chickens were fed the AUT diet compared with the other 2 treatments. There were no differences among diets in the dressing percentage. Ileal amino acid digestibility at 5 wk of age revealed only minor differences between diets. There was a tendency toward lower ileal digestibility (0.12 > P > 0.07) of Arg, Lys, Met, and Phe in the AUT diet compared with the SOY diet, whereas there were no differences between the SOY and BBP diets. Total tract amino acid digestibilities at 5 wk were similar or slightly lower than the ileal digestibilities within diets. Total tract amino acid digestibility at 2 wk was similar to the total tract amino acid digestibility at 5 wk. The diets containing bacterial protein showed lower total tract digestibility of most amino acids compared with the SOY diet. It was concluded that 6% of either basic or autolysed bacterial protein can replace soybean meal in diets for broiler chickens without impairing growth performance, and the basic bacterial protein seemed to be a slightly better substitute than the autolysed bacterial protein.

Structural dynamics of the human androgen receptor: implications for prostate cancer and neurodegenerative disease.

The AR (androgen receptor) is a ligand-activated transcription factor that mediates the action of the steroids testosterone and dihydrotestosterone. Alterations in the AR gene result in a number of clinical disorders, including: androgen-insensitivity, which leads to disruption of male development; prostate cancer; and a neuromuscular degenerative condition termed spinal bulbar muscular atrophy or Kennedy's disease. The AR gene is X-linked and the protein is coded for by eight exons, giving rise to a C-terminal LBD (ligand-binding domain; exons 4-8), linked by a hinge region (exon 4) to a Zn-finger DBD (DNA-binding domain; exons 2 and 3) and a large structurally distinct NTD (N-terminal domain; exon 1). Identification and characterization of mutations found in prostate cancer and Kennedy's disease patients have revealed the importance of structural dynamics in the mechanisms of action of receptors. Recent results from our laboratory studying genetic changes in the LBD and the structurally flexible NTD will be discussed.

Mortality while awaiting liver retransplantation: predictability of MELD scores.

INTRODUCTION: Model for End-stage Liver Disease (MELD) scores at the time of listing on the transplant waiting list have been shown to accurately predict 3-month mortality in adults. There is no data assessing the accuracy of the MELD scores in predicting mortality of patients awaiting liver retransplantation. We sought to determine the outcome of patients listed for retransplantation at a single center and the accuracy of MELD scores in predicting mortality on the transplant waiting list. METHODS: A retrospective review of adult patients at a single center listed for a second liver transplantation during the years 1993 to 2000. MELD scores and a concordance statistic were calculated at the time of initial listing and initial transplant as well as the time of relisting for a second transplant and at 2, 4, 6, 8, 12, and 24 weeks after relisting. RESULTS: Of the 63 patients in the study, 43 (68%) received a second transplant, and 20 (32%) died while awaiting retransplantation. Of the patients receiving a second transplant, 13 (30%) died within 1 year of receiving the transplant. The most common cause of death on the waiting list was sepsis (50%), hepatorenal syndrome (20%), and multiorgan failure (10%), whereas the majority of deaths posttransplantation were sepsis-related (69%). At the time of relisting the c-statistic for MELD scores predicting death after 1 week on the waiting list was 0.78 (P = .007). After 3 months on the waiting list, the c-stat was largely unchanged (0.76, P = .04). CONCLUSIONS: We have shown that MELD scores may predict mortality on the transplant waiting list for patients listed for a second transplant.

BARX2 induces cadherin 6 expression and is a functional suppressor of ovarian cancer progression.

The human homeobox BARX2 is located at 11q24-q25, within a minimal region associated with frequent loss of heterozygosity and adverse survival in epithelial ovarian cancer. BARX2 is a transcription factor that regulates transcription of specific cell adhesion molecules in the mouse. We show that BARX2 and cadherin 6 are expressed in normal human ovarian surface epithelium. BARX2 and cadherin 6 both have significantly lower expression in a clinical sample of endometrioid and clear cell ovarian cancers, as compared with serous or mixed mesodermal tumors. In a series of ovarian cancer cell lines, BARX2 expression showed a significant direct correlation with cadherin 6 expression. In OAW42, an ovarian cancer cell line that does not endogenously express BARX2, in vitro transfection of human BARX2 cDNA induced cadherin 6 expression. Transfection of BARX2 into OAW42 inhibited Matrigel invasion, haptotactic cellular migration to a collagen IV signal, and adhesion to collagen IV-coated plates. Our data demonstrate that BARX2 is expressed in the ovarian surface epithelium and has functional suppressor properties in ovarian cancer cells.

Species differences in the regio- and stereoselectivity of 1-nitronaphthalene metabolism.

1-Nitronaphthalene (1-NN) is a mutagenic nitroaromatic that has been detected in emissions from both heavy- and light-duty diesel engines, as well as in urban airborne particles. 1-NN is a cytochrome P450-bioactivated, nonciliated bronchiolar epithelial (Clara) cell cytotoxicant. Our recent studies demonstrated that 1-NN was metabolized by rat lung and liver microsomal enzymes to six 1-NN GSH conjugates via intermediate C(5),C(6)- and C(7),C(8)-epoxides. These studies examined the metabolism of 1-NN in mouse, and compared the differences in rates of 1-NN GSH conjugate formation between the two species. HPLC radioactivity profiles demonstrated that seven different conjugates were generated in mouse lung and liver microsomal incubations. Six of the seven conjugates corresponded with those observed in incubations with rat microsomes. Mass spectrometry of the new conjugate yielded a m/z 497 (M+H) and identical daughter ions as in the other six conjugates when analyzed by mass spectrometry in electrospray positive ion mode. The major conjugate generated in mouse and rat lung microsomal incubations was conjugate 4 (1-nitro-7-glutathionyl-8-hydroxy-7, 8-dihydronaphthalene). In comparison, the formation of conjugate 6 (1-nitro-5-hydroxy-6-glutathionyl-5,6-dihydronaphthalene) predominated in mouse liver, whereas in rat liver, conjugate 5, a diastereomer of conjugate 6, was generated at the highest rate. We concluded that the rates of formation of regio- and stereoisomeric epoxides from 1-NN differed substantially in target and nontarget tissues, but there was no clear pattern of correlation of tissue susceptibility to the rate or metabolite produced.

Glutathione conjugation of electrophilic metabolites of 1-nitronaphthalene in rat tracheobronchial airways and liver: identification by mass spectrometry and proton nuclear magnetic resonance spectroscopy.

1-Nitronaphthalene (1-NN) is a mutagenic nitroaromatic which has been detected in emissions from both heavy- and light-duty diesel engines, as well as in urban airborne particles. 1-NN is a cytochrome P450-bioactivated, nonciliated bronchiolar epithelial (Clara) cell cytotoxicant. These studies examined the metabolism of 1-NN to electrophilic metabolites which were trapped as glutathione conjugates in highly susceptible (lung) and less susceptible (liver) tissues of the rat. Significant depletion of reduced glutathione was observed at all levels of tracheobronchial airways of rats treated with 200 mg/kg 1-NN, ip. This observation of depleted glutathione was consistent with the HPLC radioactivity profiles demonstrating six glutathione conjugates isolated from liver and lung microsomal incubations with 1-NN, [(3)H]glutathione, and glutathione S-transferase. Mass spectrometry of all six metabolites in electrospray positive ion mode yielded an ion of m/z 497 (M + H), and daughter ions of m/z 479 (loss of water), m/z 306 (glutathione), and m/z 177 (loss of the nitro group and formation of hydroxy naphthalene thiolate ion), demonstrating the formation of hydroxy-dihydroglutathionyl derivatives presumably via intermediate epoxide(s). Proton nuclear magnetic resonance spectroscopy identified four different regioisomeric conjugates from lung and liver microsomal incubations: 1-nitro-7-glutathionyl-8-hydroxy-7, 8-dihydronaphthalene, 1-nitro-7-hydroxy-8-glutathionyl-7, 8-dihydronaphthalene, 1-nitro-5-hydroxy-6-glutathionyl-5, 6-dihydronaphthalene, and 1-nitro-5-glutathionyl-6-hydroxy-5, 6-dihydronaphthalene. HPLC radioactivity profiles demonstrated that major conjugates generated in the lung were derived from the C(7), C(8)-epoxide, whereas the most prominent metabolites in the liver were derived from the C(5),C(6)-epoxide.

Measurement of cytochrome P450 2E1 activity in rat tracheobronchial airways using high-performance liquid chromatography with electrochemical detection.

Cytochrome P450 2E1 catalyzes the metabolic activation of nitrosamines and haloalkenes to carcinogenic and cytotoxic derivatives; however, the regulation of this P450 isozyme is not well understood. Hydroxylation of p-nitrophenol to p-nitrocatechol has been used as a marker of CYP2E1 activity, but currently available methodologies are not sufficiently sensitive to allow measurements in small tissue samples or in tissues with low activity such as lung. We describe here a method for measuring p-nitrocatechol formation using HPLC with electrochemical detection which is rapid and specific. It has a level of sensitivity (pmol) sufficient to monitor CYP2E1 activities in incubations containing as little as 10 micrograms microsomal protein prepared from airway subcompartments of the lung, a tissue with low and varying CYP2E1 activities among different parts of the airways.

The cost and benefit of prophylaxis against deep vein thrombosis in elective hip replacement. DVT/PE Prophylaxis Consensus Forum.

UNLABELLED: A consensus forum was convened to evaluate the economic considerations associated with prophylaxis against thrombo-embolic disease in patients undergoing hip replacement therapy in South Africa. This forum consists of orthopaedic surgeons, vascular surgeons and a statistician. METHODS: The forum was instructed to evaluate the economic costs of the commonly used forms of prophylaxis of thrombo-embolism in patients undergoing hip replacement surgery in South Africa, looking at short-term events only. The methods used for the prophylaxis of thrombo-embolism in South Africa were determined by a postal survey. A decision tree was constructed to determine the events that will occur after a clinical decision to use no prophylaxis. The probabilities of these events were then determined. Protocols for and costs of prophylaxis and treatment were established. With the decision tree and these costs, the cost of the various modalities of prophylaxis was then determined. RESULTS: The probability, determined by the forum, of developing a deep-vein thrombosis (DVT) when no prophylaxis is used was 0.5, with a mortality rate of 2.1%. The cost of this decision was R875. No prophylaxis given, but a venogram performed on day 7, reduced the mortality rate to 0.7%; however, this cost R3 017. The cost of low-molecular-weight heparin was R1 223 (probability 0.26, mortality rate 1.1%), while unfractionated heparin with a graduated compression stocking (GCS) cost R1 351 (probability 0.24, mortality rate 1%). Aspirin with a GCS cost R777 (probability 0.35, mortality rate 1.5%).

Effects of extended sidestream smoke exposure on components of the C-fiber axon reflex.

We have previously shown that young guinea pigs repeatedly exposed to sidestream cigarette smoke (SS) develop decreased airway reactivity of the C-fiber system without changing reactivity to one of its neurotransmitters, substance P (SP). This study was designed to determine whether the decreased reactivity was due to decreased responsiveness to another neurotransmitter, neurokinin A (NKA), decreased lung SP content, decreased affinity or number of NK1 receptors, and/or decreased number of C-fibers. Duncan Hartley guinea pigs were exposed to filtered air (FA) or to SS for 6 h/day, 5 days/week for 5 weeks starting at 1 week of age. SS exposure did not change, (1) airway reactivity to NKA injected into the pulmonary artery of their isolated perfused lungs (n = 6-7 each group), (2) lung SP content as measured by enzyme immunoassay (n = 12 each group), (3) NK1 receptor number or affinity as measured by radioligand binding (n = 7 each group), or (4) SP-immunoreactive nerve profiles of the terminal bronchioles or small airways (n = 6 each group). Thus, SS exposure does not decrease C-fiber system by reducing NKA responsiveness, decreasing SP content, changing NK1 receptors, or decreasing the number of C-fibers.

cDNA for Mo3, a monocyte activation antigen, encodes the human receptor for urokinase plasminogen activator.

We have cloned the cDNA for Mo3, an activation Ag expressed by human monocytes and myelomonocytic cell lines after stimulation by PMA, LPS, muramyl dipeptide, certain cytokines, and cAMP agonists. We have previously shown that Mo3 expression in vivo is associated predominantly with macrophages in inflammatory sites. Mo3 is a highly glycosylated protein of about 50 kDa in monocytes and U-937 cells and is anchored to the plasma membrane by glycosyl-phosphatidylinositol linkage. We purified Mo3 protein by cleavage from the U-937 cell surface with phosphatidylinositol-specific phospholipase C, followed by affinity chromatography using a mAb. An internal peptide sequence was determined and used to design oligonucleotide probes for screening an expression cDNA library. Nucleotide sequencing indicated that the complete coding sequence encodes 335 amino acids, including a predicted signal peptide of 22 residues and a hydrophobic C-terminal portion that is probably cleaved during formation of the GPI linkage. The resulting mature protein of about 290 amino acids is consistent with the 29-kDa molecular mass of deglycosylated Mo3. A Northern blot of RNA from U-937 cells revealed a 1.5-kb band that was induced by PMA treatment. Mo3 cDNA was transfected into Cos cells and surface expression of Mo3 was detected by ELISA using various anti-Mo3 mAb. We performed a computer search of the National Biomedical Research Foundation database and found that Mo3 is identical to the human receptor for the urokinase plasminogen activator (uPA-R). Purified soluble Mo3, as well as anti-Mo3 antibodies, were able to block uPA binding to its receptor on U-937 cells, indicating that Mo3 is indeed uPA-R. The use of these anti-Mo3 antibodies may be helpful in assessing the role of uPA-R in processes such as inflammation and tumor invasion.

Molecular cloning of a GTPase activating protein specific for the Krev-1 protein p21rap1.

The rap1/Krev-1 gene encodes a ras-related protein that suppresses transformation by ras oncogenes. We have purified an 88 kd GTPase activating protein (GAP), specific for the rap1/Krev-1 gene product, from bovine brain. Based on partial amino acid sequences obtained from this protein, a 3.3 kb cDNA was isolated from a human brain library. Expression of the cDNA in insect Sf9 cells resulted in high level production of an 85-95 kd rap1GAP that specifically stimulated the GTPase activity of p21rap1. The complete deduced amino acid sequence is not homologous to any known protein sequences, including GAPs specific for p21ras. Northern and Western blotting analysis indicate that rap1GAP is not ubiquitously expressed and appears most abundant in fetal tissues and certain tumor cell lines, particularly the Wilms' kidney tumor, SK-NEP-1, and the melanoma, SK-MEL-3, cell lines.